Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 12/14/14
AREA FORECAST DISCUSSION
NWS PUEBLO CO
212 AM MST SAT DEC 13 2014
.UPDATE...
ISSUED AT 204 AM MST SAT DEC 13 2014
EXTENDED DENSE FOG ADVISORY INTO PUEBLO COUNTY UNTIL 16Z. ADDED
THE EASTERN SAWATCH RANGE IN THE CENTRAL MOUNTAINS TO THE WINTER
WEATHER ADVISORY FOR TONIGHT. ALSO REINITIALIZED FRONT END GRIDS
WITH LATEST OBSERVATIONAL DATA.
UPDATE ISSUED AT 747 PM MST FRI DEC 12 2014
ISSUED DENSE FOG ADVISORY FOR PARTS OF THE SOUTHEAST PLAINS GIVEN
CURRENT OBS AND SHORT RANGE GUIDANCE.
UPDATE ISSUED AT 514 PM MST FRI DEC 12 2014
BASED ON HRRR AND RAP GUIDANCE...AND CURRENT ONGOING
CONDITIONS...HAVE BROUGHT FOG AND CLOUDS FARTHER WEST UP THE ARK
RIVER LATER THIS EVENING. HRRR HAS FOG MAKING IT TO PUEBLO
WEST...BUT THIS SEEMS A BIT TOO FAR WEST. PRETTY MUCH HAVE THE LOW
CLOUDS/FOG REACHING E PUEBLO COUNTY LATER TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 245 PM MST FRI DEC 12 2014
...DRY AND MILD THROUGH MOST OF SATURDAY...
CURRENTLY...SKIES CONTAIN HIGH CLOUDS OVER MOST OF THE AREA...BUT
LOW CLOUDS ARE SEEN OVER EXTREME EASTERN PROWERS AND BACA
COUNTIES...WHICH IS ALONG THE EDGE OF A LARGE EXPANSE OF LOW CLOUDS
AND FOG OVER WESTERN KANSAS DRIFTING NORTHWARD. TEMPERATURES ACROSS
THE AREA WERE RANGING FROM THE LOWER 30S ACROSS THE CONTINENTAL
DIVIDE TO THE LOWER 70S IN THE LEE OF THE EASTERN MOUNTAINS. WINDS
ARE FAIRLY LIGHT ACROSS THE CWA...WITH A FEW LOCALLY BREEZY SPOTS
HIGH UP AND IN THE LEE OF THE EASTERN MOUNTAINS.
TONIGHT...FAIRLY TRANQUIL WEATHER WILL RULE. THE LOW CLOUDS ACROSS
THE FAR EAST WILL LIKELY EXPAND WESTWARD THROUGH THE EVENING AND
PERSIST UNTIL AFTER SUNRISE SATURDAY. AREAS OF DENSE FOG AND
FREEZING FOG WILL BE LIKELY ACROSS EASTERN KIOWA...PROWERS AND
BACA COUNTIES. THE KEY WORD IS AREAS...SO NO FOG HIGHLIGHT ISSUED
AT THIS TIME.
OVERNIGHT LOWS WILL GENERALLY BE IN THE 20S ACROSS THE PLAINS AND I-
25 CORRIDOR WITH SOME 30S UP AGAINST THE EASTERN MOUNTAINS WHICH
WILL HAVE SOME WEST BREEZES ALL NIGHT. LOWEST TEMPERATURES WILL BE
IN THE CENTRAL SAN LUIS VALLEY...WITH ALAMOSA IN THE SINGLE DIGITS
BY DAWN.
SATURDAY...FORECAST MODELS IN PRETTY GOOD AGREEMENT IN STRENGTH AND
TIMING THROUGH THE AFTERNOON. AHEAD OF THE STORM SYSTEM...MILD
WEATHER WILL PREVAIL ACROSS THE PLAINS AND I-25 CORRIDOR...BUT
PROBABLY A BIT COOLER THAN FRIDAY AS THE ATMOSPHERIC COLUMN COOLS
WITH SOUTHWEST WINDS ALOFT. STILL...HIGHS SHOULD BE IN THE UPPER 50S
TO LOWER 60S EAST...30S TO 50 HIGH VALLEYS AND 20S AND 30S ACROSS
THE HIGH COUNTRY. ALL MODELS ARE SHOWING THE CHANCE FOR
PRECIPITATION TO ARRIVE ALONG THE CONTINENTAL DIVIDE BY LATE
AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 245 PM MST FRI DEC 12 2014
SAT NIGHT THE FORECAST MODELS BRING A CLOSED LOW ACROSS NRN NM
AND SRN CO. THE GFS AND ECMWF ARE VERY SIMILAR IN TAKING THE UPR
LOW CENTER ACROSS EXTREME NRN NM SAT NIGHT AND EASTWARD INTO THE
TX AND OK PANHANDLES ON SUN. THE NAM IS A LITTLE FARTHER SOUTH
WITH THE LOW CENTER.
SAT EVENING...SNOW IS EXPECTED TO RAMP UP ALONG THE CONTDVD...WITH
THE MOST FAVORABLE MSTR FLOW BEING OVR THE ERN SAN JUAN MTNS. IN THE
LATE NIGHT HOURS...AS THE UPR TROF CONTINUES MOVING EASTWARD...PCPN
IS EXPECTED TO SPREAD OVR THE SAN LUIS VALLEY AND INTO THE SANGRE
DE CRISTO MOUNTAINS...ALTHOUGH ONLY LIGHT PCPN AMOUNTS ARE
EXPECTED IN THOSE AREAS...WHILE SNOW CONTINUES ALONG THE CONTDVD.
THE LATEST NAM12 SHOWS WIDESPREAD PCPN SPREADING INTO THE SERN
PLAINS SUN MORNING AS MID LEVEL SOUTHERLY FLOW BRINGS MSTR UP
FROM THE SOUTH. AT THE SAME TIME...THE GFS IS DRY OVR THE FAR SERN
PLAINS...WITH WIDESPREAD PCPN ALONG THE I-25 CORRIDOR. FOR SUN
MORNING THE NAM HAS NORTHEASTERLY MID LEVEL WINDS ALONG AND
ADJACENT TO THE ERN MTNS WHICH ENHANCES SNOWFALL POTENTIAL IN
PORTIONS OF FREMONT COUNTY...THE WET MTS AND SERN FOOTHILLS...AS
WELL AS NORTHERN TELLER COUNTY AND NORTHWESTERN EL PASO COUNTY.
SFC WINDS ARE BREEZY FROM THE NORTH...AND THE NAM IS SHOWING THE
LACK OF PCPN IN THE FAVORED DOWNSLOPE AREAS OF SRN EL PASO AND THE
NORTHERN HALF OF PUEBLO COUNTIES.
SUN AFTERNOON...AS THE UPR LOW MOVES INTO THE PANHANDLES...PCPN
CONTINUES ALONG THE CONTDVD...BUT THE POTENTIAL FOR SIGNIFICANT SNOW
SNOW ACCUMULATION WILL BE ON THE DECREASE. AT THIS TIME IT LOOKS
LIKE THE CENTRAL MTNS MAY NOT SEE ALL THAT MUCH
ACCUMULATION...WHILE THE ERN SAN JUAN AND LA GARITA MTNS WILL
PROBABLY SEE ADVISORY LEVEL SNOW ACCUMULATIONS. THUS WILL ISSUE
THE SNOW ADVISORY FOR THOSE LOCATIONS AND CANCEL THE WATCH. THIS
SYSTEM IS NOT ALL THAT COLD WITH THE NAM SHOWING H7 TEMPS AROUND
-2C SUN AFTERNOON...ALTHOUGH THE GFS IS A FEW DEGREES COLDER.
FORECAST HIGHS FOR THE SERN PLAINS ON SUN ARE IN THE MID TO UPPER
40S AND IF THAT HOLDS TRUE...PCPN WOULD MAINLY BE RAIN. TEMPS
ALONG THE I-25 CORRIDOR LOOKS A LITTLE COOLER. HARD TO SAY HOW
MUCH SNOW MAY FALL OVR THE SERN PLAINS ON SUN...BUT SEVERAL INCHES
ARE POSSIBLE ALONG THE ERN MTNS AND ADJACENT LOWER ELEVATIONS. MAY
END UP NEEDING ADVISORIES FOR THE WET MTNS AND PIKES PEAK AND
SANGRES...BUT WILL HOLD OFF FOR NOW AND LET LATER SHIFTS GET A
GOOD LOOK AT FUTURE MODELS RUNS.
SUN NIGHT THE FORECAST MODELS DIFFER IN THE TRACK OF THE UPR LOW
CENTER. THE GFS TAKES IT INTO SOUTH CENTRAL KS BY 06Z MON...WHILE
THE NAM MOVES IT INTO SW OK BY 06Z MON. THUS...THE GFS SHOWS WANING
PCPN CHANCES ACROSS ALL THE FORECAST AREA...WHILE THE NAM SHOWS
PCPN WRAPPING AROUND THE UPR LOW INTO SERN CO. THEN BY 12Z MON
MORNING...BOTH MODELS HAVE THE UPR LOW FAR ENOUGH EAST THAT PCPN
WILL HAVE MOSTLY ENDED ACROSS THE FORECAST AREA.
COOL TEMPS...BUT MAINLY DRY WEATHER CAN THEN BE EXPECTED FOR MON AND
TUE...BEFORE THE NEXT WEATHER SYSTEM MOVES INTO THE AREA. TUE NIGHT
AND WED A DISTURBANCE MOVES ACROSS THE STATE...BRINGING PCPN
CHANCES MAINLY TO THE CONTDVD. THEN BY THU A NEW UPR LOW IS
EXPECTED TO DIVE SOUTH INTO SRN CA AND THEN TRACK EASTWARD ACROSS SRN
AZ AND NM THU AND FRI. THAT TRACK IS A BIT TOO FAR SOUTH TO BRING
MUCH OF AN IMPACT TO OUR FORECAST AREA...BUT THERE IS STILL PLENTY
OF TIME FOR THE TRACK OF THAT SYSTEM TO CHANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1034 PM MST FRI DEC 12 2014
MAINLY VFR CONDITIONS EXPECTED COS...PUB AND ALS OVER THE NEXT 24
HOURS. IFR LOW CLOUDS AND FOG ACROSS THE LOWER ARKANSAS RIVER
VALLEY COULD ADVECT INTO PUEBLO THROUGH 12Z...THOUGH NOT CONFIDENT
ENOUGH TO PUT IN TAF ATTM. STRONG UPPER LEVEL STORM SYSTEM MOVING
ON SHORE ACROSS THE WEST COAST WILL SPREAD HIGH LEVEL CLOUDS
ACROSS THE AREA THROUGH THE DAY TOMORROW. THIS SYSTEM WILL
CONTINUE TO MOVE EAST ACROSS THE GREAT BASIN...SPREADING SNOW INTO
THE CONTDVD BY 00Z SUN...WITH A FEW POSSIBLE SHOWERS SPREADING
EAST ACROSS THE SAN LUIS VALLEY BY 06Z SUN. MVFR AND IFR
CONDITIONS IN RAIN AND SNOW CAN BE EXPECTED AT TAF SITES AFT THIS
TAF PERIOD.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM MST THIS MORNING FOR COZ086-089-
093-095>099.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM MST
SUNDAY FOR COZ058-060-066-068.
&&
$$
UPDATE...LW
SHORT TERM...TM
LONG TERM...28
AVIATION...MW
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1034 PM MST FRI DEC 12 2014
.UPDATE...
ISSUED AT 747 PM MST FRI DEC 12 2014
ISSUED DENSE FOG ADVISORY FOR PARTS OF THE SOUTHEAST PLAINS GIVEN
CURRENT OBS AND SHORT RANGE GUIDANCE.
UPDATE ISSUED AT 514 PM MST FRI DEC 12 2014
BASED ON HRRR AND RAP GUIDANCE...AND CURRENT ONGOING
CONDITIONS...HAVE BROUGHT FOG AND CLOUDS FARTHER WEST UP THE ARK
RVR LATER THIS EVENING. HRRR HAS FOG MAKING IT TO PUEBLO
WEST...BUT THIS SEEMS A BIT TOO FAR WEST. PRETTY MUCH HAVE THE LOW
CLOUDS/FOG REACHING E PUEBLO COUNTY LATER TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 245 PM MST FRI DEC 12 2014
...DRY AND MILD THROUGH MOST OF SATURDAY...
CURRENTLY...SKIES CONTAIN HIGH CLOUDS OVER MOST OF THE AREA...BUT
LOW CLOUDS ARE SEEN OVER EXTREME EASTERN PROWERS AND BACA
COUNTIES...WHICH IS ALONG THE EDGE OF A LARGE EXPANSE OF LOW CLOUDS
AND FOG OVER WESTERN KANSAS DRIFTING NORTHWARD. TEMPERATURES ACROSS
THE AREA WERE RANGING FROM THE LOWER 30S ACROSS THE CONTINENTAL
DIVIDE TO THE LOWER 70S IN THE LEE OF THE EASTERN MOUNTAINS. WINDS
ARE FAIRLY LIGHT ACROSS THE CWA...WITH A FEW LOCALLY BREEZY SPOTS
HIGH UP AND IN THE LEE OF THE EASTERN MOUNTAINS.
TONIGHT...FAIRLY TRANQUIL WEATHER WILL RULE. THE LOW CLOUDS ACROSS
THE FAR EAST WILL LIKELY EXPAND WESTWARD BY MIDEVENING AND PERSIST
UNTIL AFTER SUNRISE SATURDAY. AREAS OF DENSE FOG AND FREEZING FOG
WILL BE LIKELY ACROSS EASTERN KIOWA...PROWERS AND BACA COUNTIES. THE
KEY WORD IS AREAS...SO NO FOG HIGHLIGHT ISSUED AT THIS TIME.
OVERNIGHT LOWS WILL GENERALLY BE IN THE 20S ACROSS THE PLAINS AND I-
25 CORRIDOR WITH SOME 30S UP AGAINST THE EASTERN MOUNTAINS WHICH
WILL HAVE SOME WEST BREEZES ALL NIGHT. LOWEST TEMPERATURES WILL BE
IN THE CENTRAL SAN LUIS VALLEY...WITH ALAMOSA IN THE SINGLE DIGITS
BY DAWN.
SATURDAY...FORECAST MODELS IN PRETTY GOOD AGREEMENT IN STRENGTH AND
TIMING THROUGH THE AFTERNOON. AHEAD OF THE STORM SYSTEM...MILD
WEATHER WILL PREVAIL ACROSS THE PLAINS AND I-25 CORRIDOR...BUT
PROBABLY A BIT COOLER THAN FRIDAY AS THE ATMOSPHERIC COLUMN COOLS
WITH SOUTHWEST WINDS ALOFT. STILL...HIGHS SHOULD BE IN THE UPPER 50S
TO LOWER 60S EAST...30S TO 50 HIGH VALLEYS AND 20S AND 30S ACROSS
THE HIGH COUNTRY. ALL MODELS ARE SHOWING THE CHANCE FOR
PRECIPITATION TO ARRIVE ALONG THE CONTINENTAL DIVIDE BY LATE
AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 245 PM MST FRI DEC 12 2014
SAT NIGHT THE FORECAST MODELS BRING A CLOSED LOW ACRS NRN NM AND SRN
CO. THE GFS AND ECMWF ARE VERY SIMILAR IN TAKING THE UPR LOW CENTER
ACRS EXTREME NRN NM SAT NIGHT AND EASTWARD INTO THE TX AND OK
PANHANDLES ON SUN. THE NAM IS A LITTLE FARTHER SOUTH WITH THE LOW
CENTER.
SAT EVENING...SNOW IS EXPECTED TO RAMP UP ALONG THE CONTDVD...WITH
THE MOST FAVORABLE MSTR FLOW BEING OVR THE ERN SAN JUAN MTNS. IN THE
LATE NIGHT HOURS...AS THE UPR TROF CONTINUES MOVING EWRD...PCPN IS
EXPECTED TO SPREAD OVR THE SAN LUIS VALLEY AND INTO THE SANGRE DE
CRISTO MOUNTAINS...ALTHOUGH ONLY LIGHT PCPN AMOUNTS ARE EXPECTED IN
THOSE AREAS...WHILE SNOW CONTINUES ALONG THE CONTDVD.
THE LATEST NAM12 SHOWS WIDESPREAD PCPN SPREADING INTO THE SERN
PLAINS SUN MORNING AS MIDLEVEL SOUTHERLY FLOW BRINGS MSTR UP FROM
THE SOUTH. AT THE SAME TIME...THE GFS IS DRY OVR THE FAR SERN
PLAINS...WITH WIDESPREAD PCPN ALONG THE I-25 CORRIDOR. FOR SUN
MORNING THE NAM HAS NERLY MID LEVEL WINDS ALONG AND ADJACENT TO THE
ERN MTNS WHICH ENHANCES SNOWFALL POTENTIAL IN PORTIONS OF FREMONT
COUNTY...THE WET MTS AND SERN FOOTHILLS...AS WELL AS NORTHERN TELLER
COUNTY AND NWRN EL PASO COUNTY. SFC WINDS ARE BREEZY FROM THE
NORTH...AND THE NAM IS SHOWING THE LACK OF PCPN IN THE FAVORED
DOWNSLOPE AREAS OF SRN EL PASO AND THE NORTHERN HALF OF PUEBLO
COUNTIES.
SUN AFTERNOON...AS THE UPR LOW MOVES INTO THE PANHANDLES...PCPN
CONTINUES ALONG THE CONTDVD...BUT THE POTENTIAL FOR SIGNIFICANT SNOW
SNOW ACCUMULATION WL BE ON THE DECREASE. AT THIS TIME IT LOOKS LIKE
THE CENTRAL MTNS MAY NOT SEE ALL THAT MUCH ACCUMULATION...WHILE THE
ERN SAN JUAN AND LA GARITA MTNS WL PROBABLY SEE ADVISORY LEVEL SNOW
ACCUMULATIONS. THUS WL ISSUE THE SNOW ADVISORY FOR THOSE LOCATIONS
AND CANCEL THE WATCH. THIS SYSTEM IS NOT ALL THAT COLD WITH THE NAM
SHOWING H7 TEMPS AROUND -2C SUN AFTERNOON...ALTHOUGH THE GFS IS A
FEW DEGREES COLDER. FORECAST HIGHS FOR THE SERN PLAINS ON SUN ARE
IN THE MID TO UPPER 40S AND IF THAT HOLDS TRUE...PCPN WOULD MAINLY
BE RAIN. TEMPS ALONG THE I-25 CORRIDOR LOOKS A LITTLE COOLER. HARD
TO SAY HOW MUCH SNOW MAY FALL OVR THE SERN PLAINS ON SUN...BUT
SEVERAL INCHES ARE POSSIBLE ALONG THE ERN MTNS AND ADJACENT LOWER
ELEVATIONS. MAY END UP NEEDING ADVISORIES FOR THE WET MTNS AND
PIKES PEAK AND SANGRES...BUT WL HOLD OFF FOR NOW AND LET LATER
SHIFTS GET A GOOD LOOK AT FUTURE MODELS RUNS.
SUN NIGHT THE FORECAST MODELS DIFFER IN THE TRACK OF THE UPR LOW
CENTER. THE GFS TAKES IT INTO SOUTH CENTRAL KS BY 06Z MON...WHILE
THE NAM MOVES IT INTO SW OK BY 06Z MON. THUS...THE GFS SHOWS WANING
PCPN CHANCES ACRS ALL THE FORECAST AREA...WHILE THE NAM SHOWS PCPN
WRAPPING AROUND THE UPR LOW INTO SERN CO. THEN BY 12Z MON
MORNING...BOTH MODELS HAVE THE UPR LOW FAR ENOUGH EAST THAT PCPN WL
HAVE MOSTLY ENDED ACRS THE FORECAST AREA.
COOL TEMPS...BUT MAINLY DRY WEATHER CAN THEN BE EXPECTED FOR MON AND
TUE...BEFORE THE NEXT WEATHER SYSTEM MOVES INTO THE AREA. TUE NIGHT
AND WED A DISTURBANCE MOVES ACRS THE STATE...BRINGING PCPN CHANCES
MAINLY TO THE CONTDVD. THEN BY THU A NEW UPR LOW IS EXPECTED TO
DIVE SOUTH INTO SRN CA AND THEN TRACK EASTWARD ACS SRN AZ AND NM THU
AND FRI. THAT TRACK IS A BIT TOO FAR SOUTH TO BRING MUCH OF AN
IMPACT TO OUR FORECAST AREA...BUT THERE IS STILL PLENTY OF TIME FOR
THE TRACK OF THAT SYSTEM TO CHANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1034 PM MST FRI DEC 12 2014
MAINLY VFR CONDITIONS EXPECTED COS...PUB AND ALS OVER THE NEXT 24
HOURS. IFR LOW CLOUDS AND FOG ACROSS THE LOWER ARKANSAS RIVER
VALLEY COULD ADVECT INTO PUEBLO THROUGH 12Z...THOUGH NOT CONFIDENT
ENOUGH TO PUT IN TAF ATTM. STRONG UPPER LEVEL STORM SYSTEM MOVING
ON SHORE ACROSS THE WEST COAST WILL SPREAD HIGH LEVEL CLOUDS
ACROSS THE AREA THROUGH THE DAY TOMORROW. THIS SYSTEM WILL
CONTINUE TO MOVE EAST ACROSS THE GREAT BASIN...SPREADING SNOW INTO
THE CONTDVD BY 00Z SUN...WITH A FEW POSSIBLE SHOWERS SPREADING
EAST ACROSS THE SAN LUIS VALLEY BY 06Z SUN. MFVR AND IFR CONDITIONS
IN RAIN AND SNOW CAN BE EXPECTED AT TAF SITES AFT THIS TAF PERIOD.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM MST SATURDAY FOR COZ089-093-
095>099.
WINTER WEATHER ADVISORY FROM 6 PM SATURDAY TO 6 PM MST SUNDAY
FOR COZ066-068.
&&
$$
UPDATE...HODANISH
SHORT TERM...TM
LONG TERM...28
AVIATION...MW
AREA FORECAST DISCUSSION
NWS PUEBLO CO
752 PM MST FRI DEC 12 2014
.UPDATE...
ISSUED AT 747 PM MST FRI DEC 12 2014
ISSUED DENSE FOG ADVISORY FOR PARTS OF THE SOUTHEAST PLAINS GIVEN
CURRENT OBS AND SHORT RANGE GUIDANCE.
UPDATE ISSUED AT 514 PM MST FRI DEC 12 2014
BASED ON HRRR AND RAP GUIDANCE...AND CURRENT ONGOING
CONDITIONS...HAVE BROUGHT FOG AND CLOUDS FARTHER WEST UP THE ARK
RVR LATER THIS EVENING. HRRR HAS FOG MAKING IT TO PUEBLO
WEST...BUT THIS SEEMS A BIT TOO FAR WEST. PRETTY MUCH HAVE THE LOW
CLOUDS/FOG REACHING E PUEBLO COUNTY LATER TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 245 PM MST FRI DEC 12 2014
...DRY AND MILD THROUGH MOST OF SATURDAY...
CURRENTLY...SKIES CONTAIN HIGH CLOUDS OVER MOST OF THE AREA...BUT
LOW CLOUDS ARE SEEN OVER EXTREME EASTERN PROWERS AND BACA
COUNTIES...WHICH IS ALONG THE EDGE OF A LARGE EXPANSE OF LOW CLOUDS
AND FOG OVER WESTERN KANSAS DRIFTING NORTHWARD. TEMPERATURES ACROSS
THE AREA WERE RANGING FROM THE LOWER 30S ACROSS THE CONTINENTAL
DIVIDE TO THE LOWER 70S IN THE LEE OF THE EASTERN MOUNTAINS. WINDS
ARE FAIRLY LIGHT ACROSS THE CWA...WITH A FEW LOCALLY BREEZY SPOTS
HIGH UP AND IN THE LEE OF THE EASTERN MOUNTAINS.
TONIGHT...FAIRLY TRANQUIL WEATHER WILL RULE. THE LOW CLOUDS ACROSS
THE FAR EAST WILL LIKELY EXPAND WESTWARD BY MIDEVENING AND PERSIST
UNTIL AFTER SUNRISE SATURDAY. AREAS OF DENSE FOG AND FREEZING FOG
WILL BE LIKELY ACROSS EASTERN KIOWA...PROWERS AND BACA COUNTIES. THE
KEY WORD IS AREAS...SO NO FOG HIGHLIGHT ISSUED AT THIS TIME.
OVERNIGHT LOWS WILL GENERALLY BE IN THE 20S ACROSS THE PLAINS AND I-
25 CORRIDOR WITH SOME 30S UP AGAINST THE EASTERN MOUNTAINS WHICH
WILL HAVE SOME WEST BREEZES ALL NIGHT. LOWEST TEMPERATURES WILL BE
IN THE CENTRAL SAN LUIS VALLEY...WITH ALAMOSA IN THE SINGLE DIGITS
BY DAWN.
SATURDAY...FORECAST MODELS IN PRETTY GOOD AGREEMENT IN STRENGTH AND
TIMING THROUGH THE AFTERNOON. AHEAD OF THE STORM SYSTEM...MILD
WEATHER WILL PREVAIL ACROSS THE PLAINS AND I-25 CORRIDOR...BUT
PROBABLY A BIT COOLER THAN FRIDAY AS THE ATMOSPHERIC COLUMN COOLS
WITH SOUTHWEST WINDS ALOFT. STILL...HIGHS SHOULD BE IN THE UPPER 50S
TO LOWER 60S EAST...30S TO 50 HIGH VALLEYS AND 20S AND 30S ACROSS
THE HIGH COUNTRY. ALL MODELS ARE SHOWING THE CHANCE FOR
PRECIPITATION TO ARRIVE ALONG THE CONTINENTAL DIVIDE BY LATE
AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 245 PM MST FRI DEC 12 2014
SAT NIGHT THE FORECAST MODELS BRING A CLOSED LOW ACRS NRN NM AND SRN
CO. THE GFS AND ECMWF ARE VERY SIMILAR IN TAKING THE UPR LOW CENTER
ACRS EXTREME NRN NM SAT NIGHT AND EASTWARD INTO THE TX AND OK
PANHANDLES ON SUN. THE NAM IS A LITTLE FARTHER SOUTH WITH THE LOW
CENTER.
SAT EVENING...SNOW IS EXPECTED TO RAMP UP ALONG THE CONTDVD...WITH
THE MOST FAVORABLE MSTR FLOW BEING OVR THE ERN SAN JUAN MTNS. IN THE
LATE NIGHT HOURS...AS THE UPR TROF CONTINUES MOVING EWRD...PCPN IS
EXPECTED TO SPREAD OVR THE SAN LUIS VALLEY AND INTO THE SANGRE DE
CRISTO MOUNTAINS...ALTHOUGH ONLY LIGHT PCPN AMOUNTS ARE EXPECTED IN
THOSE AREAS...WHILE SNOW CONTINUES ALONG THE CONTDVD.
THE LATEST NAM12 SHOWS WIDESPREAD PCPN SPREADING INTO THE SERN
PLAINS SUN MORNING AS MIDLEVEL SOUTHERLY FLOW BRINGS MSTR UP FROM
THE SOUTH. AT THE SAME TIME...THE GFS IS DRY OVR THE FAR SERN
PLAINS...WITH WIDESPREAD PCPN ALONG THE I-25 CORRIDOR. FOR SUN
MORNING THE NAM HAS NERLY MID LEVEL WINDS ALONG AND ADJACENT TO THE
ERN MTNS WHICH ENHANCES SNOWFALL POTENTIAL IN PORTIONS OF FREMONT
COUNTY...THE WET MTS AND SERN FOOTHILLS...AS WELL AS NORTHERN TELLER
COUNTY AND NWRN EL PASO COUNTY. SFC WINDS ARE BREEZY FROM THE
NORTH...AND THE NAM IS SHOWING THE LACK OF PCPN IN THE FAVORED
DOWNSLOPE AREAS OF SRN EL PASO AND THE NORTHERN HALF OF PUEBLO
COUNTIES.
SUN AFTERNOON...AS THE UPR LOW MOVES INTO THE PANHANDLES...PCPN
CONTINUES ALONG THE CONTDVD...BUT THE POTENTIAL FOR SIGNIFICANT SNOW
SNOW ACCUMULATION WL BE ON THE DECREASE. AT THIS TIME IT LOOKS LIKE
THE CENTRAL MTNS MAY NOT SEE ALL THAT MUCH ACCUMULATION...WHILE THE
ERN SAN JUAN AND LA GARITA MTNS WL PROBABLY SEE ADVISORY LEVEL SNOW
ACCUMULATIONS. THUS WL ISSUE THE SNOW ADVISORY FOR THOSE LOCATIONS
AND CANCEL THE WATCH. THIS SYSTEM IS NOT ALL THAT COLD WITH THE NAM
SHOWING H7 TEMPS AROUND -2C SUN AFTERNOON...ALTHOUGH THE GFS IS A
FEW DEGREES COLDER. FORECAST HIGHS FOR THE SERN PLAINS ON SUN ARE
IN THE MID TO UPPER 40S AND IF THAT HOLDS TRUE...PCPN WOULD MAINLY
BE RAIN. TEMPS ALONG THE I-25 CORRIDOR LOOKS A LITTLE COOLER. HARD
TO SAY HOW MUCH SNOW MAY FALL OVR THE SERN PLAINS ON SUN...BUT
SEVERAL INCHES ARE POSSIBLE ALONG THE ERN MTNS AND ADJACENT LOWER
ELEVATIONS. MAY END UP NEEDING ADVISORIES FOR THE WET MTNS AND
PIKES PEAK AND SANGRES...BUT WL HOLD OFF FOR NOW AND LET LATER
SHIFTS GET A GOOD LOOK AT FUTURE MODELS RUNS.
SUN NIGHT THE FORECAST MODELS DIFFER IN THE TRACK OF THE UPR LOW
CENTER. THE GFS TAKES IT INTO SOUTH CENTRAL KS BY 06Z MON...WHILE
THE NAM MOVES IT INTO SW OK BY 06Z MON. THUS...THE GFS SHOWS WANING
PCPN CHANCES ACRS ALL THE FORECAST AREA...WHILE THE NAM SHOWS PCPN
WRAPPING AROUND THE UPR LOW INTO SERN CO. THEN BY 12Z MON
MORNING...BOTH MODELS HAVE THE UPR LOW FAR ENOUGH EAST THAT PCPN WL
HAVE MOSTLY ENDED ACRS THE FORECAST AREA.
COOL TEMPS...BUT MAINLY DRY WEATHER CAN THEN BE EXPECTED FOR MON AND
TUE...BEFORE THE NEXT WEATHER SYSTEM MOVES INTO THE AREA. TUE NIGHT
AND WED A DISTURBANCE MOVES ACRS THE STATE...BRINGING PCPN CHANCES
MAINLY TO THE CONTDVD. THEN BY THU A NEW UPR LOW IS EXPECTED TO
DIVE SOUTH INTO SRN CA AND THEN TRACK EASTWARD ACS SRN AZ AND NM THU
AND FRI. THAT TRACK IS A BIT TOO FAR SOUTH TO BRING MUCH OF AN
IMPACT TO OUR FORECAST AREA...BUT THERE IS STILL PLENTY OF TIME FOR
THE TRACK OF THAT SYSTEM TO CHANGE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 245 PM MST FRI DEC 12 2014
FOR THE THREE TERMINALS...VFR CONDITIONS WILL LAST FOR THE NEXT 24
HOURS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 9 AM MST SATURDAY FOR COZ089-093-
095>099.
WINTER WEATHER ADVISORY FROM 6 PM SATURDAY TO 6 PM MST SUNDAY
FOR COZ066-068.
&&
$$
UPDATE...HODANISH
SHORT TERM...TM
LONG TERM...28
AVIATION...TM
AREA FORECAST DISCUSSION
NWS PUEBLO CO
516 PM MST FRI DEC 12 2014
.UPDATE...
ISSUED AT 514 PM MST FRI DEC 12 2014
BASED ON HRRR AND RAP GUIDANCE...AND CURRENT ONGOING
CONDITIONS...HAVE BROUGHT FOG AND CLOUDS FARTHER WEST UP THE ARK
RVR LATER THIS EVENING. HRRR HAS FOG MAKING IT TO PUEBLO
WEST...BUT THIS SEEMS A BIT TOO FAR WEST. PRETTY MUCH HAVE THE LOW
CLOUDS/FOG REACHING E PUEBLO COUNTY LATER TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 245 PM MST FRI DEC 12 2014
...DRY AND MILD THROUGH MOST OF SATURDAY...
CURRENTLY...SKIES CONTAIN HIGH CLOUDS OVER MOST OF THE AREA...BUT
LOW CLOUDS ARE SEEN OVER EXTREME EASTERN PROWERS AND BACA
COUNTIES...WHICH IS ALONG THE EDGE OF A LARGE EXPANSE OF LOW CLOUDS
AND FOG OVER WESTERN KANSAS DRIFTING NORTHWARD. TEMPERATURES ACROSS
THE AREA WERE RANGING FROM THE LOWER 30S ACROSS THE CONTINENTAL
DIVIDE TO THE LOWER 70S IN THE LEE OF THE EASTERN MOUNTAINS. WINDS
ARE FAIRLY LIGHT ACROSS THE CWA...WITH A FEW LOCALLY BREEZY SPOTS
HIGH UP AND IN THE LEE OF THE EASTERN MOUNTAINS.
TONIGHT...FAIRLY TRANQUIL WEATHER WILL RULE. THE LOW CLOUDS ACROSS
THE FAR EAST WILL LIKELY EXPAND WESTWARD BY MIDEVENING AND PERSIST
UNTIL AFTER SUNRISE SATURDAY. AREAS OF DENSE FOG AND FREEZING FOG
WILL BE LIKELY ACROSS EASTERN KIOWA...PROWERS AND BACA COUNTIES. THE
KEY WORD IS AREAS...SO NO FOG HIGHLIGHT ISSUED AT THIS TIME.
OVERNIGHT LOWS WILL GENERALLY BE IN THE 20S ACROSS THE PLAINS AND I-
25 CORRIDOR WITH SOME 30S UP AGAINST THE EASTERN MOUNTAINS WHICH
WILL HAVE SOME WEST BREEZES ALL NIGHT. LOWEST TEMPERATURES WILL BE
IN THE CENTRAL SAN LUIS VALLEY...WITH ALAMOSA IN THE SINGLE DIGITS
BY DAWN.
SATURDAY...FORECAST MODELS IN PRETTY GOOD AGREEMENT IN STRENGTH AND
TIMING THROUGH THE AFTERNOON. AHEAD OF THE STORM SYSTEM...MILD
WEATHER WILL PREVAIL ACROSS THE PLAINS AND I-25 CORRIDOR...BUT
PROBABLY A BIT COOLER THAN FRIDAY AS THE ATMOSPHERIC COLUMN COOLS
WITH SOUTHWEST WINDS ALOFT. STILL...HIGHS SHOULD BE IN THE UPPER 50S
TO LOWER 60S EAST...30S TO 50 HIGH VALLEYS AND 20S AND 30S ACROSS
THE HIGH COUNTRY. ALL MODELS ARE SHOWING THE CHANCE FOR
PRECIPITATION TO ARRIVE ALONG THE CONTINENTAL DIVIDE BY LATE
AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 245 PM MST FRI DEC 12 2014
SAT NIGHT THE FORECAST MODELS BRING A CLOSED LOW ACRS NRN NM AND SRN
CO. THE GFS AND ECMWF ARE VERY SIMILAR IN TAKING THE UPR LOW CENTER
ACRS EXTREME NRN NM SAT NIGHT AND EASTWARD INTO THE TX AND OK
PANHANDLES ON SUN. THE NAM IS A LITTLE FARTHER SOUTH WITH THE LOW
CENTER.
SAT EVENING...SNOW IS EXPECTED TO RAMP UP ALONG THE CONTDVD...WITH
THE MOST FAVORABLE MSTR FLOW BEING OVR THE ERN SAN JUAN MTNS. IN THE
LATE NIGHT HOURS...AS THE UPR TROF CONTINUES MOVING EWRD...PCPN IS
EXPECTED TO SPREAD OVR THE SAN LUIS VALLEY AND INTO THE SANGRE DE
CRISTO MOUNTAINS...ALTHOUGH ONLY LIGHT PCPN AMOUNTS ARE EXPECTED IN
THOSE AREAS...WHILE SNOW CONTINUES ALONG THE CONTDVD.
THE LATEST NAM12 SHOWS WIDESPREAD PCPN SPREADING INTO THE SERN
PLAINS SUN MORNING AS MIDLEVEL SOUTHERLY FLOW BRINGS MSTR UP FROM
THE SOUTH. AT THE SAME TIME...THE GFS IS DRY OVR THE FAR SERN
PLAINS...WITH WIDESPREAD PCPN ALONG THE I-25 CORRIDOR. FOR SUN
MORNING THE NAM HAS NERLY MID LEVEL WINDS ALONG AND ADJACENT TO THE
ERN MTNS WHICH ENHANCES SNOWFALL POTENTIAL IN PORTIONS OF FREMONT
COUNTY...THE WET MTS AND SERN FOOTHILLS...AS WELL AS NORTHERN TELLER
COUNTY AND NWRN EL PASO COUNTY. SFC WINDS ARE BREEZY FROM THE
NORTH...AND THE NAM IS SHOWING THE LACK OF PCPN IN THE FAVORED
DOWNSLOPE AREAS OF SRN EL PASO AND THE NORTHERN HALF OF PUEBLO
COUNTIES.
SUN AFTERNOON...AS THE UPR LOW MOVES INTO THE PANHANDLES...PCPN
CONTINUES ALONG THE CONTDVD...BUT THE POTENTIAL FOR SIGNIFICANT SNOW
SNOW ACCUMULATION WL BE ON THE DECREASE. AT THIS TIME IT LOOKS LIKE
THE CENTRAL MTNS MAY NOT SEE ALL THAT MUCH ACCUMULATION...WHILE THE
ERN SAN JUAN AND LA GARITA MTNS WL PROBABLY SEE ADVISORY LEVEL SNOW
ACCUMULATIONS. THUS WL ISSUE THE SNOW ADVISORY FOR THOSE LOCATIONS
AND CANCEL THE WATCH. THIS SYSTEM IS NOT ALL THAT COLD WITH THE NAM
SHOWING H7 TEMPS AROUND -2C SUN AFTERNOON...ALTHOUGH THE GFS IS A
FEW DEGREES COLDER. FORECAST HIGHS FOR THE SERN PLAINS ON SUN ARE
IN THE MID TO UPPER 40S AND IF THAT HOLDS TRUE...PCPN WOULD MAINLY
BE RAIN. TEMPS ALONG THE I-25 CORRIDOR LOOKS A LITTLE COOLER. HARD
TO SAY HOW MUCH SNOW MAY FALL OVR THE SERN PLAINS ON SUN...BUT
SEVERAL INCHES ARE POSSIBLE ALONG THE ERN MTNS AND ADJACENT LOWER
ELEVATIONS. MAY END UP NEEDING ADVISORIES FOR THE WET MTNS AND
PIKES PEAK AND SANGRES...BUT WL HOLD OFF FOR NOW AND LET LATER
SHIFTS GET A GOOD LOOK AT FUTURE MODELS RUNS.
SUN NIGHT THE FORECAST MODELS DIFFER IN THE TRACK OF THE UPR LOW
CENTER. THE GFS TAKES IT INTO SOUTH CENTRAL KS BY 06Z MON...WHILE
THE NAM MOVES IT INTO SW OK BY 06Z MON. THUS...THE GFS SHOWS WANING
PCPN CHANCES ACRS ALL THE FORECAST AREA...WHILE THE NAM SHOWS PCPN
WRAPPING AROUND THE UPR LOW INTO SERN CO. THEN BY 12Z MON
MORNING...BOTH MODELS HAVE THE UPR LOW FAR ENOUGH EAST THAT PCPN WL
HAVE MOSTLY ENDED ACRS THE FORECAST AREA.
COOL TEMPS...BUT MAINLY DRY WEATHER CAN THEN BE EXPECTED FOR MON AND
TUE...BEFORE THE NEXT WEATHER SYSTEM MOVES INTO THE AREA. TUE NIGHT
AND WED A DISTURBANCE MOVES ACRS THE STATE...BRINGING PCPN CHANCES
MAINLY TO THE CONTDVD. THEN BY THU A NEW UPR LOW IS EXPECTED TO
DIVE SOUTH INTO SRN CA AND THEN TRACK EASTWARD ACS SRN AZ AND NM THU
AND FRI. THAT TRACK IS A BIT TOO FAR SOUTH TO BRING MUCH OF AN
IMPACT TO OUR FORECAST AREA...BUT THERE IS STILL PLENTY OF TIME FOR
THE TRACK OF THAT SYSTEM TO CHANGE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 245 PM MST FRI DEC 12 2014
FOR THE THREE TERMINALS...VFR CONDITIONS WILL LAST FOR THE NEXT 24
HOURS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 6 PM SATURDAY TO 6 PM MST SUNDAY
FOR COZ066-068.
&&
$$
UPDATE...HODANISH
SHORT TERM...TM
LONG TERM...28
AVIATION...TM
AREA FORECAST DISCUSSION...UPDATED
NWS TAMPA BAY RUSKIN FL
710 PM EST SAT DEC 13 2014
.UPDATE (REST OF TONIGHT AND SUNDAY)...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A LARGE SCALE OMEGA BLOCK
PATTERN ACROSS NORTH AMERICA WITH A DEEP TROUGH/CLOSED LOW OVER THE
INTERMOUNTAIN WEST...A HIGH AMPLITUDE RIDGE THROUGH THE CENTER OF
THE COUNTRY...AND ANOTHER CLOSED LOW/DEEP TROUGH EXITING THE EASTERN
SEABOARD. UNLIKE THE NAME "BLOCK" SUGGESTS...THIS TIME THE PATTERN
WILL REMAIN SOMEWHAT PROGRESSIVE WITH ALL THESE FEATURES PUSHING
EASTWARD THROUGH THE EARLY PORTION OF THE WEEK. THE FLORIDA
PENINSULA RESIDES NEAR THE BASE OF THE TROUGH MOVING OFF THE EAST
COAST...ALTHOUGH THE MAIN TROUGH AXIS HAS PAST OFF TO THE EAST. WV
IMAGERY SHOWS A VERY DRY MID/UPPER LEVEL ENVIRONMENT...AND THIS IS
CONFIRMED BY THE 14/00Z KTBW SOUNDING PROFILE. SIGNIFICANT DEWPOINT
DEPRESSION ARE SEEN THROUGH THE EXTENT OF THE COLUMN WITH A PW VALUE
AROUND 0.3". THIS VALUE IS BELOW THE 10TH PERCENTILE FOR THE MIDDLE
OF DECEMBER. NO BIG SURPRISE OUR SKIES ARE COMPLETELY CLEAR.
AT THE SURFACE...HIGH PRESSURE WILL HOLD OVER MUCH OF THE DEEP SOUTH
AND TN VALLEY. ALTHOUGH THE HIGH CENTER IS FAR TO THE NORTH...A
RIDGE AXIS EXTENDS SOUTHWARD INTO THE FLORIDA PENINSULA. THIS
RIDGE AXIS WILL PROMOTE BOTH A TENDENCY FOR THE BOUNDARY LAYER TO
DECOUPLE OVERNIGHT AND ALSO A GOOD COLD AIR DRAINAGE SETUP INTO THE
NATURE COAST ZONES. THE SETUP IS EVEN SLIGHTLY BETTER THAN WHAT WAS
SEEN ON FRIDAY NIGHT...WHEN A RAPID DECOUPLING OF THE BOUNDARY LAYER
WAS SEEN AFTER SUNSET ACROSS THE NATURE COAST AND A RAPID
TEMPERATURE DROP WITHIN THE FIRST FEW HOURS AFTER SUNSET. EXPECT
(AND SEEING) A SIMILAR SCENARIO THIS EVENING...WITH STRONG
RADIATIONAL COOLING GIVEN THE CLEAR SKIES...AND DRY BOUNDARY LAYER
DEWPOINTS. TEMPERATURES ARE ALREADY DROPPING RAPIDLY...AND SHOULD
REACH THE UPPER 30S BY THE END OF THE EVENING FOR NORMALLY COLDER
SPOTS ACROSS THE NATURE COAST. AS IS OFTEN THE CASE DURING
RADIATIONAL COOLING SCENARIOS...A SLOWER TEMPERATURE DECLINE IS THEN
LIKELY THROUGH THE REST OF THE NIGHT AFTER THE QUICK EVENING DROP.
FURTHER SOUTH...THE DECOUPLING SHOULD TAKE LONGER AND THE
TEMPERATURE DECLINE BE A BIT SLOWER...HOWEVER MANY INLAND SPOTS WILL
STILL SEE LOW TEMPERATURES DOWN INTO THE UPPER 30S AND LOWER 40S BY
SUNRISE. LOW TEMPERATURES ACROSS THE NATURE COAST WILL END UP IN THE
LOWER 30S...WITH A FEW NORMALLY COLDER SPOTS POSSIBLY REACHING THE
UPPER 20S AROUND DAWN. A FREEZE WARNING CONTINUES FOR LEVY...
CITRUS...AND HERNANDO COUNTIES FOR EXPECTATION OF SEVERAL HOURS AT
OR JUST BELOW FREEZING IN THE HOURS LEADING UP TO DAWN. SUMTER AND
INLAND PASCO COUNTIES ARE UNDER FROST ADVISORIES...AS WIDESPREAD
FREEZING TEMPERATURES ARE NOT EXPECTED...BUT THE DECOUPLED
CONDITIONS AND TEMPERATURES IN THE MIDDLE 30S WILL PROMOTE AREAS TO
WIDESPREAD FROST FORMATION. FURTHER SOUTH...DO ANTICIPATE PATCHY
FROST FOR THE NORMALLY COLDER AND MORE SHELTERED LOCATIONS UNDER
RADIATIONAL COOLING CONDITIONS...HOWEVER THE MORE ISOLATED NATURE OF
THE FROST SHOULD MAKE AN ADVISORY UNNECESSARY AT THIS TIME. THE
"WARMEST LOCATIONS OVERNIGHT WILL BE THE SOUTHERN HALF OF PINELLAS
COUNTY...AND THE SANIBEL REGION OF CHARLOTTE HARBOR WHERE A DRAINAGE
FLOW FROM THE NORTHEAST OFF THE BAY WATERS WILL HELP KEEP LOW
TEMPERATURES GENERALLY IN THE UPPER 40S TO NEAR 50.
SUNDAY...THE SURFACE HIGH WILL REMAIN IN PLACE THROUGH THE DAY...
HOWEVER...ALOFT THE RIDGE CURRENTLY TO OUR WEST WILL BE BUILDING
INTO THE REGION. GENERAL HEIGHT RISES AND THE RESULTING STACKED
RIDGING IN PLACE BY THE END OF THE DAY SHOULD CERTAINLY HELP IN
MODERATING OUR TEMPERATURES. AFTER A CHILLY START TO THE
MORNING...THE DIURNAL SWING WILL BE QUITE DRAMATIC. TEMPERATURES
WILL REBOUND QUICKLY AND MODERATE A COUPLE OF DEGREES FROM THE HIGHS
SEEN ON SATURDAY...WITH MID AFTERNOON TEMPERATURES GENERALLY UPPER
60S NORTH...TO AROUND 70 THROUGH THE I-4 CORRIDOR...AND LOWER 70S
DOWN BY FORT MYERS. TIME HEIGHT FORECASTS SHOW LITTLE IF ANY
MOISTURE RETURN UNDER THE BUILDING HIGH. SO WITH ESSENTIALLY NO
SYNOPTIC MECHANISM FOR LIFT AND A VERY DRY COLUMN IN PLACE...NEAR
100% OF THE POSSIBLE SUNSHINE IS AGAIN EXPECTED.
HAVE A GREAT SATURDAY EVENING EVERYBODY AND STAY WARM!
&&
.LONG TERM (SUNDAY NIGHT-FRIDAY NIGHT)...
LOW PRESSURE IS MOVING AWAY FROM THE COAST OF NEW ENGLAND SUNDAY
NIGHT INTO MONDAY...WITH HIGH PRESSURE RESTING OVER THE EASTERN
THIRD OF THE UNITED STATES. THIS WILL ALLOW DRIER CONDITIONS OVER
THE FORECAST AREA TO CONTINUE.
GUIDANCE HAS THE NEXT FRONTAL SYSTEM MOVING IN ON TUESDAY NIGHT INTO
WEDNESDAY. AS THE FRONT MOVES THROUGH...IT WILL NOT HAVE MUCH
MOISTURE TO PROVIDE MENTIONABLE RAIN CHANCES. MOST GUIDANCE HAS THE
FRONT EITHER MOVING SOUTH OF THE STATE OR WEAKENING OUT OF EXISTENCE
BY THURSDAY. DRY AIR REINFORCES ITS PRESENCE ON FRIDAY...WITH
ANOTHER SYSTEM MOVING INTO THE THE MISSISSIPPI RIVER VALLEY.
TEMPERATURES WILL BE CHILLY WITH THE CRISP...DRIER AIR...THOUGH THE
AIR MASS SHOULD MODERATE ALLOWING TEMPERATURES TO BECOME MILDER AS
THE PERIOD CONTINUES. GLOBAL GUIDANCE IS IN SURPRISINGLY GOOD
AGREEMENT WITH SYNOPTIC FEATURES AND TIMING THROUGH THE EXTENDED.
WILL NEED TO MONITOR TRENDS...BUT THE LACK OF MOISTURE WILL LIMIT
RAIN CHANCES TO POSSIBLY AT THE END OF THE FORECAST PERIOD...WHERE
CONFIDENCE IS THE LEAST.
&&
.AVIATION...
VFR CONDITIONS PREVAIL THROUGH THE TAF PERIOD WITH CLEAR SKIES AND
VARIABLE WINDS GENERALLY UNDER 6 KNOTS.
&&
.MARINE...
HIGH PRESSURE CENTERED OVER THE EASTERN UNITED STATES WILL REMAIN
IN PLACE FOR THE NEXT FEW DAYS. LIGHT NORTH WINDS WILL CONTINUE THIS
EVENING AND WEAKEN SLIGHTLY AND TURN NORTHEAST BY SUNRISE. WINDS
WILL RELAX ON SUNDAY...AND BECOME VERY LIGHT FOR MONDAY AND TUESDAY.
THE NEXT FRONTAL SYSTEM IS DUE TUESDAY NIGHT OR WEDNESDAY BUT THIS
WILL HAVE LITTLE OR NO EFFECT ON THE WATERS AND VERY LIGHT WINDS
WILL LAST THROUGH THE WEEK. DRY WEATHER THROUGH THE PERIOD. NO
HEADLINES ANTICIPATED.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 45 69 49 70 / 0 0 0 0
FMY 46 72 49 74 / 0 0 0 0
GIF 41 69 47 70 / 0 0 0 0
SRQ 43 68 47 69 / 0 0 0 0
BKV 30 69 37 70 / 0 0 0 0
SPG 51 67 55 69 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...FREEZE WARNING FROM 4 AM TO 9 AM EST SUNDAY FOR COASTAL
CITRUS-COASTAL HERNANDO-COASTAL LEVY-INLAND CITRUS-
INLAND HERNANDO-INLAND LEVY.
FROST ADVISORY FROM 4 AM TO 9 AM EST SUNDAY FOR INLAND
PASCO-SUMTER.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION...MROCZKA
LONG TERM...GARCIA
MARINE...DOUGHERTY
AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NWS KEY WEST FL
1000 AM EST FRI DEC 12 2014
.DISCUSSION...IN THE MID AND UPPER LEVELS...LATEST IR IMAGERY
OVERLAID WITH MODEL STREAMLINE ANALYSIS AND OBSERVATIONS AS OF 900
AM DEPICT A SLOWLY FILLING AND ELONGATING MIDDLE AND UPPER LOW
PRESSURE SYSTEM POSITIONED OVER WESTERN MAINE. THIS SYSTEM IS STILL
EMBEDDED WITHIN STAGNANT TROUGH/RIDGE/TROUGH LONGWAVE PATTERN FROM
WEST TO EAST ACROSS THE CONUS...BUT A NEARLY ZONAL/WEAKLY
ANTICYCLONIC UPPER LEVEL JET WITH AN AVERAGE 75 TO 100 KNOT
WESTERLIES AT 250 MB IS ROARING ACROSS OLD MEXICO...THE GULF OF
MEXICO...AS WELL AS SOUTH FLORIDA AND THE FLORIDA KEYS.
AT THE SURFACE AND IN THE LOWER TO MIDDLE LEVELS...LATEST VISIBLE
IMAGERY OVERLAID WITH AVAILABLE MARINE AND LAND SURFACE OBSERVATIONS
AS OF 900 AM DETAILS A NEAR 1030 MB SURFACE RIDGE ORIENTED FROM THE
SOUTHERN OHIO VALLEY DOWN TO THE SOUTHERN MISSISSIPPI VALLEY. BUT
LOCALLY...NEAR 1025 MB RIDGING IS STILL HOLDING TO THE IMMEDIATE
NORTH OF THE SOUTH FLORIDA PENINSULA. THIS IS RESULTING IN GENTLE TO
MODERATE NORTHEASTERLIES RIGHT AT THE SURFACE. BUT THE 12Z SOUNDING
ILLUSTRATED LIGHT AND VARIABLE WINDS RIGHT OFF OF THE
SURFACE...BECOMING NORTHWEST AND FRESHENING TO THE 854 MB BASE OF A
FAIRLY STRONG 6 DEGREE INVERSION UP TO 813 MB. WITH THE EXCEPTION
OF THIS SHALLOW CLOUD LAYER SUPPORTING STRATOCUMULUS...THE COLUMN
WAS MODERATELY DRY WITH COLUMNAR PWAT (PRECIPITABLE WATER) AOA TWO
THIRDS OF AN INCH OR .67 INCHES.
.CURRENTLY...AS OF 900 AM...SKIES ARE PARTLY CLOUDY OWING TO THE
AFOREMENTIONED STRATOCUMULUS CLOUDS. TEMPERATURES HAVE REACHED THE
MIDDLE 60S ACROSS THE ISLAND CHAIN WITH DEWPOINTS IN THE MIDDLE TO
UPPER 50S. C-MAN STATIONS ALONG THE FLORIDA REEF ARE NORTHEAST
BETWEEN 9 AND 14 KNOTS...EXCEPT 5 TO 10 KNOTS IN FLORIDA BAY AND 13
KNOTS AT SMITH SHOAL...HOWEVER C-MANS ARE NOW SHOWING INCREASING
NORTHEASTERLIES BETWEEN 16 AND 23 KNOTS ACROSS THE WESTERN FLORIDA
STRAITS FROM SAND KEY OUT TO THE DRY TORTUGAS.
.FORECAST...REST OF TODAY...IT NOW APPEARS THE 1025 MB RIDGING TO
OUR IMMEDIATE NORTH OVER THE SOUTH FLORIDA PENINSULA MAY BE
CONSOLIDATING WITH THIS STRONGER 1030 MB RIDGING OVER THE LOWER
MISSISSIPPI VALLEY...WHICH IS RESULTING IN A BETTER MSLP GRADIENT
BETWEEN SOUTHWEST FLORIDA AND THE LOWER KEYS AND WESTERN WATERS.
THIS IS ALSO INDICATED IN THE LATEST MSAS PRESSURE ANALYSIS.
THEREFORE GIVEN THE PRESSURE AND DENSITY DIFFERENCES BETWEEN THE
SOUTHWEST FLORIDA MAINLAND AND THE WESTERN KEYS AND SURROUNDING
WATERS...WE ARE SEEING STRONGER WINDS RESULTING FROM DENSITY
DIFFERENCES...I.E COLD AIR DRAINAGE FLOW OFF OF THE SOUTHWESTERN
FLORIDA PENINSULA...WHERE TEMPERATURES ARE ONLY IN THE LOWER AND
MIDDLE 50S...AND TEMPERATURE ACROSS THE WESTERN KEYS ARE IN THE
UPPER 60S. SO EXPECT THIS SURGE TO CONTINUE THROUGH LATE THIS
MORNING AND EARLY THIS AFTERNOON...THEN DECREASE AGAIN BY MID
AFTERNOON. AN UPDATE TO THE PUBLIC ZONES WILL SPLIT OFF THE LOWER
KEYS FOR HIGHER WINDS THIS MORNING AND EARLY AFTERNOON.
&&
.MARINE...AS MENTIONED ABOVE...WINDS ARE ALSO MORE NORTHEASTERLY AND
ARE HIGHER THAN ANTICIPATED THIS MORNING ACROSS ALL
WATERS...ESPECIALLY ACROSS THE WESTERN FLORIDA STRAITS. WILL
CONTINUE TO MONITOR THROUGH THE 10 CLOCK HOUR AND IF WINDS CONTINUE
AT THESE MAGNITUDES AN UPDATE MAY BE PERFORMED TO SPLIT OFF THE
WESTERN WATERS AND INTRODUCE A EXERCISE CAUTIONARY STATEMENT OR
SMALL CRAFT ADVISORY FOR THE AFTERNOON. THE LOCAL HRRR DOES SHOW A
SURGE LATE THIS MORNING/EARLY THIS AFTERNOON...BUT IT IS OF LESS
MAGNITUDE THAN WE ARE CURRENTLY EXPERIENCING.
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL AT THE ISLAND TERMINALS
TODAY...WITH PERIODS OF VFR CEILINGS AROUND 5000 FT...ESPECIALLY
EARLY. SURFACE WINDS WILL BE OUT OF THE NORTH NEAR 10 KNOTS WITH
OCCASIONAL GUSTS OF 15 TO 20 KNOTS AT EYW...AND SOMEWHAT LESS AT MTH.
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE/GRIDS........................................FUTTERMAN
AVIATION/NOWCASTS..........................................11
UPPER AIR/ACQUISITION......................................PARKE
VISIT US ON THE WEB AT WEATHER.GOV/KEY
FOLLOW US ON FACEBOOK AND TWITTER AT...
WWW.FACEBOOK.COM/NWSKEYWEST
WWW.TWITTER.COM/NWSKEYWEST
AREA FORECAST DISCUSSION
NWS POCATELLO ID
905 PM MST SAT DEC 13 2014
.UPDATE...RADAR SHOWING PERSISTENT AREA OF LIGHT SNOW ACROSS MUCH
OF THE SOUTHEAST HALF OF EAST IDAHO. BAND INITIALLY STARTED JUST
NORTH OF FAVORED CONVERGENT ZONE IN UPPER PLAIN THEN SLOWLY SPREAD
SOUTH ALONG I-15 TOWARD POCATELLO. NEW BAND HAS DEVELOPED FROM
ROUGHLY SUN VALLEY SOUTHEAST TOWARD AND ALONG THE I-84 CORRIDOR TO
THE UTAH LINE. SNOW DEVELOPING MAINLY NORTHEAST OF WEAK
CIRCULATION EVIDENT IN WV IMAGERY OVER SOUTHWEST IDAHO. 00Z NAM IN
FAVOR OF MAINTAINING THIS BAND ALONG WITH WIDER AREA OF PRECIP
OVER SOUTHEAST HIGHLANDS THROUGH REMAINDER OF TONIGHT AS FEATURE
CLOSES AND SAGS SOUTHEAST INTO UTAH. HRRR AND WRF LESS INCLINED TO
KEEP BAND GOING BUT DO MAINTAIN FAVORABLE MOISTURE PROFILES IN
REGION OF LOW LEVEL OROGRAPHIC INFLUENCE. THUS HAVE NUDGED
POP/QPF/SNOW UPWARD SLIGHTLY OVER INTERSTATE CORRIDOR FOR THE
REMAINDER OF TONIGHT. SNOW IS STARTING TO STICK PER WEB CAMS AT
LEAST IN GRASSY AREAS BUT STILL DO NOT EXPECT SIGNIFICANT
ACCUMULATIONS OVERNIGHT. DMH
&&
.PREV DISCUSSION... /ISSUED 155 PM MST SAT DEC 13 2014/
SHORT TERM...TONIGHT THROUGH TUESDAY. SATELLITE IMAGERY WAS SHOWING
A SPLITTING UPPER TROUGH ADVANCING THROUGH THE INTERMOUNTAIN WEST
WITH THE NRN BRANCH OF THE SPLIT SHIFTING EAST THROUGH IDAHO EARLY
THIS AFTERNOON. LOCAL RADAR RETURNS AND OBSERVATIONS CONTINUED TO
SHOW SCATTERED SHOWERS...PRIMARILY SNOW...ADVANCING THROUGH THE
AREA. NUMERICAL MODELS SHOW THE NRN BRANCH OF THE SPLIT UPPER TROUGH
DECOUPLING FROM THE STRONGER FLOW TO THE NORTH AND SPINNING OFF A
WEAK CLOSED UPPER LOW WHICH LINGERS OVER SE IDAHO THROUGH SUNDAY
AFTERNOON BEFORE EXITING EAST INTO WYOMING. THUS HAVE INCREASED THE
POTENTIAL FOR SNOWFALL ACROSS THE REGION TONIGHT FAVORING THE ERN
HIGHLANDS UNDER UPSLOPE FLOW. SUNDAY NIGHT/MONDAY...A MODEST HIGH
PRESSURE RIDGE BEGINS TO SLOWLY BUILD INTO THE REGION AHEAD OF
ANOTHER INCOMING SPLIT TROUGH WHICH IS EXPECTED TO SHEAR INTO SRN
IDAHO LATE TUESDAY. HARD TO GET TOO EXCITED ABOUT SNOW ACCUMULATIONS
UNDER A SPLIT TROUGH...HOWEVER THIS STORM IS ANOTHER SLOW MOVER SO
WE MAY SEE SOME MODEST ACCUMULATIONS IN THE MOUNTAINS OVER THE TWO
DAY PERIOD RUNNING THROUGH WEDNESDAY. HUSTON
LONG TERM...TUESDAY NIGHT THROUGH SATURDAY NIGHT. THE MODELS
CONTINUE WITH SPLIT FLOW FOR THE MIDDLE OF NEXT WEEK...WITH SOME
MOISTURE AND ENERGY MOVING ACROSS IDAHO. THERE IS STILL THE QUESTION
AS TO HOW MUCH WILL BE THERE FOR POTENTIAL RAIN AND SNOW. THE GFS IN
THE PAST 24 HOURS HAS GONE WITH A WEAKER SPLIT AND HAS MORE MOISTURE
OVER EASTERN IDAHO. THE ECMWF HAS SWUNG A LITTLE BIT THE OTHER WAY
WITH A LITTLE LESS PRECIPITATION OVER US BUT STILL NOT NECESSARILY A
STRONG SPLIT PATTERN. THE ENSEMBLES STILL LEAN TOWARD A POSSIBLE
WEAKER SPLIT. AS THE UNCERTAINTY FACTOR CONTINUES...WE ARE NOT
TRYING TO MAKE ANY MAJOR SWINGS ONE WAY OR THE OTHER AND JUST
BASICALLY TWEAK THE FORECAST WHERE WE CAN. THE FORECAST STILL CALLS
FOR SOME RAIN AND SNOW ESPECIALLY OVER THE MOUNTAINS. HIGH PRESSURE
IS EXPECTED TO OVERHEAD ON FRIDAY FOR DRIER CONDITIONS. THE NEXT
SYSTEM ARRIVES IN TIME FOR NEXT WEEKEND...AND MORE OF THE SAME
INDECISION ON HOW SPLIT FLOW PLAYS OUT WITH THIS STORM. KEYES
AVIATION...CONDITIONS HAVE IMPROVED AT KSUN AND KBYI THIS
AFTERNOON...ALTHOUGH SOME PASSING SHOWERS ARE STILL POSSIBLE.
MEANWHILE...AS THE STORM HAS DRIFTED EAST WE CONTINUE WITH MVFR/IFR
WEATHER AT KIDA AND KPIH. ANY MAJOR IMPROVEMENTS MAY NOT COME UNTIL
LATER THIS EVENING AT THOSE AIRPORTS. WE STRESS IF BECAUSE THE
LATEST FORECAST KEEPS LOW CEILINGS EVEN AFTER SNOW ENDS AT KIDA. AS
THE WINDS DIE DOWN TONIGHT...MOISTURE PROFILES SUGGEST LOW CEILINGS
REDEVELOP AT KBYI AND KPIH AS THERE IS PLENTY OF MOISTURE IN PLACE
AND UPSLOPE FLOW INTO THE NEARBY TERRAIN. THE TAFS REFLECT THAT
POTENTIAL AS WE GET CLOSER TO 10-12Z (3-5AM). IF CEILINGS DEVELOP AS
FORECAST...IMPROVING CONDITIONS WON`T LIKELY OCCUR UNTIL SUNDAY
AFTERNOON AT THE EARLIEST. KSUN SHOULD BE FINE AND OUT OF ANY LOW
CEILINGS/VISIBILITY AS NORTHWEST FLOW AND WINDS KEEP EVERYTHING OUT
OF THE AREA. KEYES
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1154 AM CST SAT DEC 13 2014
.SHORT TERM...
TODAY THROUGH SUNDAY NIGHT...
327 AM...FORECAST CONCERNS INCLUDE FOG...DRIZZLE...CLOUD COVER
AND TEMPS.
BACK EDGE OF THE CLOUDS MOVED INTO THE WESTERN CWA EARLIER THIS
MORNING BUT HAS STRUGGLED TO MOVE FURTHER EAST IN THE PAST FEW
HOURS. MEANWHILE...LOW LEVEL MOISTURE...AND ITS ASSOCIATED CLOUD
COVER/DENSE FOG...IS SURGING NORTHEAST ACROSS IA AND WILL SPREAD
INTO NORTHWEST IL OVER THE NEXT FEW HOURS. WITH DEWPOINTS IN THE
LOWER TO MID 40S PLOWING INTO AIR IN THE LOWER/MID 30S...DENSE FOG
HAS BECOME QUITE WIDESPREAD ACROSS NORTHERN/NORTHEAST IA. AT ITS
CURRENT SPEED...THIS WOULD BE INTO THE NORTHWEST CWA BETWEEN 13Z
AND 15Z AND WILL CARRY AREAS OF DENSE FOG BUT CONFIDENCE REGARDING
HOW FAR EAST THE POTENTIAL WILL EXIST AS WELL AS HOW LONG IT WILL
LAST IS LOW. TRENDS WILL NEED TO BE MONITORED FOR ANY POSSIBLE
ADVISORIES LATER THIS MORNING.
THE WESTERN EDGE OF THE CURRENT CLOUD COVER WILL LIKELY STILL MAKE
SOME EAST PUSH BUT EVENTUALLY CLOUDS/FOG SPREADING IN FROM THE
WEST WILL MEET UP WITH THIS DECK. WHILE THERE COULD BE SOME BREAKS
IN THE CLOUDS THIS MORNING OR MAYBE A FEW HOUR PERIOD OF SOME SUN...
HAVE TRENDED BACK CLOUDY BY MID/LATE MORNING ACROSS THE ENTIRE
AREA. CLOUD COVER THEN STAYS LOCKED IN THROUGH THE REST OF THE
WEEKEND WITH THE SATURATED LAYER SLOWLY DEEPENING TONIGHT INTO
SUNDAY WITH SOME PATCHY DRIZZLE POSSIBLE...ESPECIALLY OVERNIGHT
INTO SUNDAY MORNING.
TEMPERATURES TODAY SHOULD REACH THE MID 40S MOST AREAS DRIVEN ALL
BY ADVECTION. POSSIBLE THE EASTERN CWA MAY ONLY REACH THE LOWER
40S THIS AFTERNOON. TEMPS THEN LIKELY TO ONLY DROP A FEW DEGREES
THIS EVENING...REMAINING STEADY OR SLOWLY RISING OVERNIGHT. HIGHS
ON SUNDAY WILL RISE INTO THE LOWER 50S ACROSS MUCH OF THE CWA WITH
A FEW MID 50S POSSIBLE...ESPECIALLY ACROSS THE SOUTHWEST CWA.
WITH CONTINUED SOUTHERLY FLOW SUNDAY NIGHT...TEMPS WILL ONLY
SLOWLY DROP INTO THE MID/UPPER 40S BY MONDAY MORNING.
INCLUDED PATCHY DRIZZLE AND FOG SUNDAY NIGHT. CONFIDENCE IS
SOMEWHAT LOW BUT FORECAST SOUNDINGS SHOW SOME POTENTIAL. CMS
&&
.LONG TERM...
MONDAY THROUGH FRIDAY...
327 AM...LOW PRESSURE WILL MOVE FROM THE PLAINS ON SUNDAY TO THE
WESTERN GREAT LAKES REGION BY TUESDAY MORNING AND THEN TO NEAR
LAKE HURON TUESDAY NIGHT. MODELS ARE SOMEWHAT CONSISTENT IN
SHOWING A LEADING WAVE/BAND OF LIGHT RAIN MIDDAY/EARLY AFTERNOON
WITH THE BULK OF THE RAIN THEN SPREADING ACROSS THE AREA LATE IN
THE AFTERNOON AND CONTINUING MONDAY NIGHT. THE EARLIER THE RAIN
ARRIVES...THE LESS LIKELY TEMPS WILL HAVE A CHANCE TO WARM. BUT
BUMPED HIGH TEMPS UP A FEW DEGREES INTO THE LOWER 50S...WITH
HIGHER CONFIDENCE EASTERN AREAS. WINDS SHIFT WESTERLY OVERNIGHT
INTO TUESDAY MORNING AS THE LOW PASSES TO THE NORTH OF THE CWA.
COLDER AIR SEEMS A BIT SLOWER TO SPREAD INTO THE AREA BUT STILL
EXPECT MORNING HIGHS THEN SLOWLY FALLING TEMPS THROUGH THE 30S FOR
THE REST OF THE DAY. BULK OF THE QPF STILL APPEARS TO BE EXITING
BEFORE THE COLUMN IS COLD ENOUGH FOR SNOW...BUT A MIX/TRANSITION
TO SNOW IS STILL POSSIBLE BEFORE PRECIP ENDS TUESDAY.
HIGH PRESSURE MOVES ACROSS THE REGION TUESDAY NIGHT INTO WEDNESDAY
AND THEN LARGE DIFFERENCES REMAIN FOR THURSDAY AS THE GFS QUICKLY
SPREADS PRECIP BACK ACROSS THE AREA WITH THE GEM/ECMWF MAINTAINING
THE HIGH AND SUPPRESSING PRECIP TO THE SOUTHWEST OF THE AREA. WENT
WITH THIS DRIER SOLUTION THRU THURSDAY NIGHT THEN MAINTAINED LOW
CHANCE POPS FRIDAY. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* IFR/LIFR CIGS AND MVFR/IFR VSBY IN FOG EXPECTED TO LINGER INTO
SUNDAY WITH OCCASIONAL FLUCTUATIONS.
* PATCHY DRIZZLE POSSIBLE TONIGHT/SUNDAY.
* WEST WINDS NEAR 10 KT BECOMING SOUTH-SOUTHWEST LESS THAN 10 KT
TONIGHT AND SUNDAY.
RATZER
//DISCUSSION...UPDATED 18Z...
TERMINALS REMAIN UNDER INFLUENCE OF "DIRTY" HIGH PRESSURE RIDGE
AXIS WHICH STRETCHES FROM HIGH PRESSURE OVER TENNESSEE NORTHWEST TO
THE UPPER MISSISSIPPI RIVER VALLEY. SOUTHWEST LOW LEVEL WINDS WEST
OF THIS RIDGE AXIS CONTINUE TO ADVECT MILDER...MOIST AIR INTO THE
REGION...WHILE SIGNIFICANT WARMING ALOFT OVER THE PAST FEW DAYS
HAS LED TO THE DEVELOPMENT AND MAINTENANCE OF A STRONG INVERSION
BASED AROUND 3000 FT AGL. MOISTURE...IN VISIBLE FORM OF LOW CLOUDS
AND FOG...REMAIN TRAPPED BENEATH THIS INVERSION RESULTING IN
EXTENSIVE IFR/LIFR/VLIFR CONDITIONS ACROSS IA/SOUTHEAST
MN...SOUTHERN WI AND FAR NORTHERN IL. EXTENSIVE LIFR WHICH SPREAD
EAST ACROSS MUCH OF NORTHERN IL THIS AM CONTINUES TO SPREAD EAST
INTO CHICAGO REGION...THOUGH WITH SLIGHTLY HIGHER CIG/VIS
CONDITIONS AT FAVORABLE DIURNAL TIMING FOR AVOIDING SOLID LIFR.
MOST OF THIS HAS REMAINED NORTH OF THE INTERSTATE 80 CORRIDOR
(MLI-VYS-GYY) THROUGH MIDDAY...WITH MVFR/VFR CONDITIONS JUST TO
THE SOUTH. VISIBLE SATELLITE INDICATES SOME THINNING NEAR GBG-MLI
WHICH MAY SIGNAL SOME IMPROVEMENT FOR SOUTHERN TERMINALS VERY LATE
THIS AFTERNOON/EARLY EVENING TO MVFR...THOUGH CONTINUED MOIST
ADVECTION AND ARRIVAL OF HIGHER DEW POINT AIR TONIGHT IS EXPECTED
TO AGAIN ALLOW CIGS/VIS TO DETERIORATE. CIG HEIGHTS AS LOW AS
200-400 FT POSSIBLE AND WITH VSBYS GENERALLY 1-3SM...THOUGH ALSO
POSSIBLY LOWER WITH ANY PATCHY DRIZZLE. VERY SHALLOW NATURE OF
CLOUD LAYER AND RATHER WEAK FORCING WITH CURRENT WEATHER
SITUATION LEADS TO SOMEWHAT POOR HANDLING BY FORECAST MODELS...
AND MAKES FOR A RATHER LOW CONFIDENCE CIG/VIS FORECAST RIGHT INTO
SUNDAY WITH LITTLE CHANGE IN STAGNANT WEATHER PATTERN UNTIL
STRONGER LOW PRESSURE SYSTEM APPROACHES LATER SUNDAY NIGHT.
WINDS FROM THE WEST AROUND 10 KTS EVEN SHOWING A FEW HIGHER GUSTS
AT MIDDAY...THOUGH TREND SHOULD BE FORE WINDS TO DIMINISH UNDER 10
KT AND BECOME SOUTHWEST THIS EVENING...AND SOUTH ON SUNDAY.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM FOR CEILING/VSBY TRENDS...LOW IN DETAILS.
* MEDIUM-HIGH FOR WINDS.
* LOW IN TIMING PERIODS OF DRIZZLE.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z...
SUNDAY NIGHT...IFR LIKELY. PATCHY FOG AND DRIZZLE. SOUTH WINDS.
MONDAY...IFR LIKELY. CHANCE OF RAIN. SOUTH WINDS.
TUESDAY...MVFR. CHANCE OF RAIN AND SNOW. GUSTY WEST WINDS.
WEDNESDAY...MVFR POSSIBLE. NORTHWEST WINDS.
THURSDAY...VFR. EAST WINDS.
FRIDAY...MVFR/IFR POSSIBLE. CHANCE OF SNOW. EAST WINDS.
MTF
&&
.MARINE...
130 AM CST
CONTINUED WEST TO SOUTHWEST WINDS WILL PREVAIL OVER THE LAKE THIS
WEEKEND WITH GENERAL LOW PRESSURE WELL TO THE NORTH AND HIGH
PRESSURE ACROSS THE OHIO RIVER VALLEY. GRADUALLY INCREASING MOISTURE
IN THE LOW-LEVELS WITH DEW POINTS EVENTUALLY REACHING AND TOPPING
LAKE SURFACE TEMPERATURES SHOULD FAVOR EXPANSION OF FOG ACROSS THE
LAKE BY THE LATTER HALF OF THIS WEEKEND. ON MONDAY...LOW PRESSURE
WILL APPROACH FROM THE SOUTHERN PLAINS AND BY LATE MONDAY NIGHT INTO
EARLY TUESDAY PHASE WITH AN UPPER MIDWEST LOW. WHERE EXACTLY THIS
OCCURS HAS SPREAD IN THE MODEL GUIDANCE...THOUGH IT LOOKS TO BE
SOMEWHERE OVER THE LAKE. THE STRONGEST WINDS WITH THIS SYSTEM STILL
LOOK TO BE ON ITS BACKSIDE AND HAVE CONTINUED TO GO DETERMINISTIC
WITH 30 KT COLD AIR ADVECTION WINDS SPREADING OVER THE LAKE TUESDAY
INTO TUESDAY NIGHT. HIGH PRESSURE LOOKS TO EVENTUALLY MOVE OVER THE
WESTERN LAKES BEHIND THIS SYSTEM...GETTING INTO THE THURSDAY TIME
FRAME OR SO.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...DENSE FOG ADVISORY...ILZ003-ILZ004-ILZ005-ILZ008-ILZ011 UNTIL
NOON SATURDAY.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1151 AM CST Sat Dec 13 2014
.UPDATE...
ISSUED AT 1049 AM CST SAT DEC 13 2014
Made no changes to the going forecast this morning: however, will
need to keep a close eye on sky trends over the next couple of
hours in order to determine how much clearing will take place
across parts of central Illinois. 16z/10am visible satellite
imagery shows a large hole in the overcast across the SW KILX CWA
around Jacksonville and Winchester...with thinning spots noted
further northeast along the I-55 corridor. 12z KILX upper air
sounding still shows a strong subsidence inversion at around
850mb, but the moist layer trapped beneath it is much thinner than
it was 24 hours ago. As a result, think there is a better chance
at seeing a little sunshine across parts of the area today as the
cloud cover tries to erode. Latest HRRR indicates this trend as well,
but tends to keep the overall condition mostly cloudy through the
day.
&&
.SHORT TERM...(Today)
ISSUED AT 300 AM CST SAT DEC 13 2014
High pressure centered just southeast of Illinois with a 500 mb
ridge axis drifting slowly toward the Midwest will maintain a strong
inversion based at 900 mb today. This inversion will trap moisture
near the surface over central Illinois, while warm moist advection
at low levels begins to push additional moisture into the region.
The result will be continued low cloudiness and several degrees of
warming compared with Friday. By evening, there could even be some
areas of drizzle as weak low level isentropic lift takes place.
Although there have been some breaks in the cloudiness overnight,
these are likely to continue to erode as has been the trend on
satellite imagery the past few hours. Widespread thin fog has been
observed overnight, but this should erode by late morning with
daytime heating. Winds will continue to be light southwesterly.
&&
.LONG TERM...(Tonight through Friday)
ISSUED AT 300 AM CST SAT DEC 13 2014
Main concern for the remainder of the weekend is with the plague of
clouds that refuses to go away. With upper ridge only drifting
through the Mississippi Valley, model forecast soundings are in no
hurry to get rid of the low level inversion. Some weak lift will be
approaching from the west late Saturday night, and with the shallow
moist column (generally 3000 feet or less), this should be enough to
wring out some mist/drizzle and keep the haze or light fog in place.
Have focused the better chances of this in the grids for late
Saturday night and early Sunday. The extent of clouds puts a bit of
a question on high temperatures Sunday, but it still appears that
50s should be widespread.
A piece of energy from the deep trough currently over California and
Nevada will intensify into a closed upper low, as it moves through
the 4 corners region tonight. It will then begin to slide northeast
before reaching Illinois Monday night. Evening model suite in
reasonable agreement with bringing the surface low into eastern Iowa
by Monday evening. Have made some adjustments to the timing of the
associated rain shield, increasing PoP`s late Sunday night to around
60% in the extreme southwest CWA near Jacksonville and Rushville,
then continued 60-70% across the board throughout Monday. Steadiest
rain will linger north of I-74 into the evening, then diminish from
southwest to northeast overnight as the low pulls into the western
Great Lakes.
Model agreement begins to break down as the week progresses. At
issue is a northern stream trough/low that will be dropping out of
the Canadian prairie provinces on Monday, reaching North Dakota on
Tuesday. The ECMWF and GEM models shunt this eastward into the Great
Lakes, while the GFS gets it caught in a bit of a Rex block
configuration before retrograding it back northwest later in the
week. This causes some complication with a broad trough in the
southern stream, which will be emerging onto the southern Plains.
The GFS is more progressive and organizes a surface cyclone which
would be spreading precipitation into our area as early as Wednesday
night. The latest ECMWF catches the state in a narrow upper ridge
into early Friday, and shunts the entire storm system to our south
late week as a stronger piece of energy dives southeast through the
central Plains. The model solutions this far out have been less than
stable, so am not inclined to go with more than slight chance PoP`s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1151 AM CST SAT DEC 13 2014
MVFR conditions prevail at all central Illinois terminals late
this morning, except KSPI where ceilings have improved into the
VFR category. Visible satellite imagery continues to show a large
break in the overcast east of the Illinois River from just south
of KPIA to west of KSPI. This area of clearing is moving eastward
and may result in the clouds temporarily breaking up at KSPI over
the next couple of hours before clouds return after 20z. Elsewhere
around the area, will monitor satellite imagery for temporary
breaks this afternoon, but will maintain MVFR ceilings through the
entire 18z TAF period. Forecast soundings are once again showing
fog developing overnight, much like it did last night. Have included
reduced visbys down to around 2-3sm after 03z accordingly. Based
on a persistence forecast, ceilings should remain MVFR tonight
into early Sunday morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Onton
LONG TERM...Geelhart
AVIATION...Barnes
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
130 AM CST SAT DEC 13 2014
.SHORT TERM...
257 PM CST
THROUGH SATURDAY...
BIT OF A TRICKY FORECAST THROUGH THE PERIOD REGARDING FOG...DRIZZLE
AND TEMPERATURE TRENDS. AREA IS ON EASTERN SIDE OF ANOMALOUS UPPER
RIDGE...BUT WITH EXPANSIVE SFC RIDGE NOT MOVING MUCH THROUGH THE
PERIOD...MIXING WILL BE VERY SHALLOW. THUS STRONG LOW LEVEL
INVERSION WILL REMAIN IN PLACE...SO WE WONT BE ABLE TO TAP INTO THE
WARMEST AIR ALOFT ON SATURDAY AND WILL KEEP A THICK STRATUS DECK.
HOWEVER...GRADUAL LOW LEVEL WARM AND MOIST ADVECTION SHOULD RESULT
IN STEADY TO SLOWLY RISING TEMPERATURES OVERNIGHT FROM THEIR LATE
AFTERNOON LEVELS IN THE LOWER TO UPPER 30S. HAVE GONE WITH WARMEST
GUIDANCE AND NON-DIURNAL TREND FOR TONIGHTS TEMPERATURES AND
EXPECTING UPPER 30S TO AROUND 40 BY DAYBREAK SATURDAY.
FORECAST SOUNDINGS SHOW WEAK LIFT IN SFC TO ROUGHLY 925 MB
LAYER...WITH POTENTIAL FOR AT LEAST PATCHY DRIZZLE TO DEVELOP FROM
WEST TO EAST OVERNIGHT AND THEN AREA WIDE THROUGH SATURDAY. THINK
THAT LIGHT QPF BEING ADVERTISED BY MOST GUIDANCE IS A BIT
OVERDONE...SO HAVE KEPT POPS BELOW MENTIONABLE BUT CANNOT COMPLETELY
RULE OUT NEEDING ISOLATED POPS. DESPITE THICK STRATUS...VERY LOW
DEWPOINT DEPRESSIONS WILL LIKELY AID IN PATCHY TO AREAS OF FOG THIS
EVENING INTO SATURDAY MORNING...AND PATCHY FOG POSSIBLY LINGERING
INTO SATURDAY AFTERNOON. WITH MILD STARTING POINT ON SATURDAY...DID
NOT MAKE BIG CHANGES TO GOING HIGH TEMPERATURE FORECAST. CONTINUED
GRADUAL LOW LEVEL WARM ADVECTION AND DEWPOINTS RISING INTO THE UPPER
30S-LOWER 40S SUPPORTS GENERALLY MID 40S...WITH A FEW UPPER 40S
POSSIBLE IN SPOTS.
RC
&&
.LONG TERM...
257 PM CST
SUNDAY NIGHT THROUGH FRIDAY...
THE UPPER RIDGE AXIS MOVES OVERHEAD SATURDAY NIGHT...THEN BEGINS TO
SHIFT EASTWARD THROUGH THE DAY ON SUNDAY. THE DEEP UPPER LOW
CURRENTLY OFF THE CALIFORNIA COAST WILL BE MOVING INTO THE
CENTRAL AND SOUTHERN PLAINS SUNDAY AFTERNOON. THE STRONG LARGER
SCALE TEMPERATURE INVERSION IN PLACE ON SATURDAY WEAKENS ON
SUNDAY...THOUGH THERE LOOKS TO BE A WEAKER SECONDARY WARM AIR
ADVECTION SURGE ON SUNDAY AHEAD OF THE UPPER LOW WHICH LOOKS TO
KEEP A LOW LEVEL INVERSION IN PLACE. PLENTY OF LOW CLOUDS AND EVEN
SOME DRIZZLE OVERNIGHT WILL LINGER INTO THE MORNING HOURS YET
AGAIN. WE WILL HAVE A SLIGHTLY BETTER CHANCE GET SOME CLOUD BREAKS
AS A MODEST SURFACE PRESSURE GRADIENT SETS UP BETWEEN THE
DEPARTING HIGH IN THE TENNESSEE VALLEY AND THE LOW IN THE PLAINS.
BUT MORE GETTING MORE OPTIMISTIC IN MORE THAN BROKEN CLOUDS WOULD
BE AMBITIOUS. THAT BEING SAID...DEWPOINTS CONTINUE TO CREEP
UPWARDS INTO AT LEAST THE MID 40S. THEREFORE MANY AREAS STILL HAVE
A DECENT CHANCE TO MAKE A RUN AT 50 DEGREES...ESPECIALLY SOUTH AND
WESTERN AREAS THAT STAND A BETTER CHANCE OF GETTING SOME
ADDITIONAL CLEARING AND EVEN PUSH THE MID 50S. THEN AGAIN SOME
GUIDANCE LIKE THE SREF PLUMES ARE SUGGESTING THAT AREAS NORTH MAY
PEAK OUT IN THE UPPER 40S.
ON MONDAY THE UPPER LOW EJECTS NORTH AND EAST...BEFORE MOVING
OVERHEAD AND OFF TO THE EAST LATER MONDAY NIGHT. SOME MODEL
DISAGREEMENT AS TO HOW FAR NORTH THE LOW WILL MOVE..BUT MODELS
GENERALLY AGREE IN AREAS OF RAINFALL THROUGH THE DAY. HAVE CONTINUED
WITH THE HIGH CHANCE TO LIKELY POPS AS PRECIPITABLE WATER VALUES
INCREASE AHEAD OF THE LOW WITH DECENT MOISTURE ADVECTION...DESPITE
THERMAL PROFILES SUGGEST PRECIPITATION WILL FALL IN THE FORM OF
RAIN.
LATE MONDAY NIGHT INTO TUESDAY THE SURFACE MOVES OVER AND THEN EAST
OF LAKE MICHIGAN AS MODEST HIGH PRESSURE BUILDS SOUTH FROM CENTRAL
CANADA. COLD AIR WILL MOVE IN ON THE BACK SIDE OF THE LOW WITH A
PROGRESSION TO LIGHT RAIN AND POSSIBLY LIGHT SNOW MIXING IN THROUGH
THE DAY. IT ALSO LOOKS TO BE MODESTLY BREEZY ON TUESDAY AS LOW LEVEL
LAPSE RATES IN THE COLD ADVECTION REGIME INCREASE...AND MORE
WINTER-LIKE TEMPERATURES MAKE THEIR RETURN. IT ALSO LOOKS TO REMAIN
CLOUDY AS STRATUS REMAINS TRAPPED UNDER AN INVERSION.
TUESDAY NIGHT WE LOSE THE DEEPER MOISTURE...AND SOME EARLY CLEARING
WILL ALLOW TEMPS TO DIP INTO THE 20S AND WIND CHILLS BACK INTO THE
TEENS. FOR THOSE OF YOU CRAVING FOR MORE SUNSHINE...WEDNESDAY
LOOKS TO BE THE BEST CHANCE AT THIS POINT. A BIT MORE UNCERTAINTY
BEYOND THIS TIME FRAME AS THE MODELS STRUGGLE WITH THE EVOLUTION
OF A TROUGH DIGGING OUT OF CANADA AND A PACIFIC LOW PROGGED TO
MOVE EAST LATER IN THE WEEK. THIS WILL PLAY A ROLE IN HOW COLD IT
GETS MID WEEK AND WHETHER OR NOT THE SOUTHERN STREAM WILL IMPACT
OUR AREA LATE WEEK. THURSDAY IS THE QUESTION MARK DAY AS THE GFS
BRINGS SOME PACIFIC ENERGY THROUGH THE AREA BEFORE HIGH PRESSURE
TAKES CONTROL WHEREAS THE ECMWF/GEM KEEP THINGS DRY THROUGH FRIDAY
BEFORE THE PACIFIC LOW GETS CLOSER TO THE AREA. CONFIDENCE IS
SOMEWHAT LOW DURING THIS TIME FRAME AND HAVE SOME LOWER POPS IN
PLACE.
KMD
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* IFR CIGS LIFTING TO MVFR BEFORE TEMPORARY SCATTERING PRIOR TO OR
NEAR DAYBREAK.
* VISIBILITY GRADUALLY LOWERING THROUGH THE NIGHT WITH IFR
POSSIBLE NEAR DAYBREAK.
* MVFR AND POSSIBLY IFR CIGS RETURNING LATER SATURDAY MORNING OR
AFTERNOON.
* SMALL CHANCE FOR DRIZZLE AT TIMES.
//DISCUSSION...UPDATED 06Z...
A CONTINUED CHALLENGING AVIATION FORECAST IN SPECIFICS WITH A
STAGNANT PATTERN OF A WEAK HIGH PRESSURE RIDGE ACROSS IL AND
SOUTHERN WI. CURRENT AREA OF IFR AND MVFR CIGS ACROSS NORTHERN AND
CENTRAL IL IS CONTINUING TO MOVE EAST BUT ITS BACK EDGE HAS
SLOWED. IT IS DIFFICULT TO SAY IF FULL SCATTERING WILL HAPPEN AT
CHICAGOLAND TAF SITES BUT SHOULD AT RFD. SOME FURTHER VISIBILITY
REDUCTION IS LIKELY AT ALL SITES TONIGHT IRREGARDLESS OF
SCATTERING THOUGH NO SHARP DROPS IN VISIBILITY ARE EXPECTED WITH
SOME WIND AND GIVEN UPSTREAM OBSERVATION BEHAVIOR.
WHILE THERE ARE SOME MINOR UNDULATIONS...THE OVERALL REGIONAL
WEATHER PATTERN REMAINS ONE OF GRADUALLY INCREASING LOW-LEVEL
MOISTURE AND A SHARPENING INVERSION JUST OFF THE SURFACE. THE
NEXT BATCH OF LOW CLOUDS WITHIN THIS IS EXPANDING RAPIDLY AS OF
530Z INTO CENTRAL IA WITH EAST-NORTHEAST DEVELOPMENT EXPECTED
THROUGH THE NIGHT...POTENTIALLY NEARING RFD BY DAYBREAK. DO THINK
THERE IS LIKELIHOOD OF SOME OF THESE CLOUDS...OR DEVELOPMENT FROM
THIS AREA OF INCREASING MOISTURE...TO BRING A RETURN TO BROKEN AND
OVERCAST LOW MVFR OR IFR TO THE TAF SITES BY LATER SATURDAY
MORNING OR AFTERNOON.
CONFIDENCE OBVIOUSLY LOWERS FURTHER IN THE TAF BUT CEILING AND
VISIBILITY CONDITIONS ARE SLIGHTLY MORE FAVORED TO DETERIORATE
FURTHER AFTER DARK SATURDAY NIGHT AND HAVE LEANED THAT ROUTE IN
THE TAF. CANNOT RULE OUT SOME PATCHY DRIZZLE AS WELL.
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* WHILE LOW IN SPECIFICS OF CIG AND VISIBILITY THROUGH MUCH OF THE
TAF...HIGH THAT CONDITIONS SHOULD NOT DROP BELOW 1SM AND/OR 500
FT THROUGH EARLY SATURDAY EVENING.
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...MVFR CIGS PROBABLE...IFR POSSIBLE.
MONDAY...MVFR CIGS PROBABLE...IFR BECOMING LIKELY AT NIGHT. RAIN
DEVELOPING LATE.
TUESDAY...CHANCE OF -RA OR -SN...MAINLY EARLY. MVFR CIGS LIKELY.
WEDNESDAY AND THURSDAY...MVFR CIGS POSSIBLE.
MTF/IZZI
&&
.MARINE...
130 AM CST
CONTINUED WEST TO SOUTHWEST WINDS WILL PREVAIL OVER THE LAKE THIS
WEEKEND WITH GENERAL LOW PRESSURE WELL TO THE NORTH AND HIGH
PRESSURE ACROSS THE OHIO RIVER VALLEY. GRADUALLY INCREASING MOISTURE
IN THE LOW-LEVELS WITH DEW POINTS EVENTUALLY REACHING AND TOPPING
LAKE SURFACE TEMPERATURES SHOULD FAVOR EXPANSION OF FOG ACROSS THE
LAKE BY THE LATTER HALF OF THIS WEEKEND. ON MONDAY...LOW PRESSURE
WILL APPROACH FROM THE SOUTHERN PLAINS AND BY LATE MONDAY NIGHT INTO
EARLY TUESDAY PHASE WITH AN UPPER MIDWEST LOW. WHERE EXACTLY THIS
OCCURS HAS SPREAD IN THE MODEL GUIDANCE...THOUGH IT LOOKS TO BE
SOMEWHERE OVER THE LAKE. THE STRONGEST WINDS WITH THIS SYSTEM STILL
LOOK TO BE ON ITS BACKSIDE AND HAVE CONTINUED TO GO DETERMINISTIC
WITH 30 KT COLD AIR ADVECTION WINDS SPREADING OVER THE LAKE TUESDAY
INTO TUESDAY NIGHT. HIGH PRESSURE LOOKS TO EVENTUALLY MOVE OVER THE
WESTERN LAKES BEHIND THIS SYSTEM...GETTING INTO THE THURSDAY TIME
FRAME OR SO.
MTF
&&
.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:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1149 PM CST Fri Dec 12 2014
.UPDATE...
ISSUED AT 855 PM CST FRI DEC 12 2014
Main concerns this evening, as in recent nights, revolve around
cloud/fog conditions and impact on low temperatures if any clearing
develops. Low level moisture trapped beneath a stout subsidence
inversion has resulted in central and southeast Illinois being
cloudy more often than not the past several days. However, there
have also been several periods with partial or total clearing that
have been tough to forecast/pinpoint. The forecast for the
remainder of the night is no different with respect to this recent
forecast difficulty.
A fairly narrow area of clearing just upstream across parts of
Iowa and Missouri is making rapid progress toward the western
portion of the forecast area. The clear area has been and is
expected to shrink with time as weak WAA persists to the west of
the nearby ridge axis. The weak lift associated with this should
help to keep clouds in place below the subsidence inversion, and
develop clouds where there currently are none. However, can`t
ignore the clearing that is approaching from the west, and that
the latest HRRR suggests will persist for a while longer.
Plan to update the forecast for the latest trends. Most tweaks
will be minor, but will be more notable to the sky condition in the
western portion of the forecast area. Hopefully the developing WAA
will preclude a significant temperature drop in the clear area.
Also have to keep an eye on the clear area resulting in
thicker/possibly dense fog development.
&&
.SHORT TERM...(Tonight)
ISSUED AT 244 PM CST FRI DEC 12 2014
Regional upper air soundings continue to show a strong subsidence
inversion centered at 850mb. Low-level moisture trapped beneath
this inversion has led to overcast conditions across central
Illinois this afternoon. Latest satellite imagery shows plenty of
clearing from the St. Louis area eastward across southern Illinois:
however, it does not appear this clearing will work its way
northward into central Illinois. The far southern KILX CWA from
Flora eastward to Lawrenceville will likely see a period of mostly
sunny skies this afternoon before clouds return this evening.
Forecast soundings for tonight suggest the low clouds will remain in
place, with the main question being whether or not significant fog
will develop. Visibilities dropped to between 1 and 3 miles along
the I-74 corridor early this morning and with the airmass remaining
unchanged/stagnant, see no reason why the same will not happen again
late tonight into tomorrow morning. Current surface observations
from across the area still show at least some restriction to
visibility, so surface-based airmass remains quite moist. With no
appreciable southerly flow developing to help scour out the
moisture, think fog will be widespread across the entire CWA
tonight. Forecast soundings appear to be the most saturated
along/north of I-74, so this is the area most likely to see
potentially dense fog later tonight. Confidence is not high enough
to issue a Dense Fog Advisory, so will only mention areas of fog in
the forecast at this time. Overnight low temperatures will bottom
out in the middle 30s.
&&
.LONG TERM...(Saturday through Friday)
ISSUED AT 244 PM CST FRI DEC 12 2014
The morning upper air showed a strong upper low off the CA coast
this morning, with a 300mb jet of 115 kt on the east side of low,
moving onshore. Exiting upper low over New England was also seen,
with ridge axis over west central plains, starting to move a little
to the east. Moisture channel satellite imagery depicts the west
coast low beginning to move onshore, which will be the system to
gradually move through the southern Rockies and eventually affect
the Midwest by the first of next week. Boundary layer on the back
side of exiting surface high, shows southerly flow of increasing
moisture and warm air to continue to move into Midwest. Result will
be cloudiness and warming temperatures into the weekend. Have added
areas of L-F for most of period until the pcpn reaches the area late
Sunday night. There is deep low level moisture trapped below
inversion and weak lift, so minor periods of drizzle possible.
New EUR brings in pcpn Monday early, little faster than GFS and so
kept qpf similar to previous forecast. POPS in the likely Category
with the closed low forecast to move over state Monday and Monday
night. Pcpn amounts though will be light, as upper low filling by
time it reaches region.
The second system to approach area expected Wednesday night, as a
minor shortwave progged to move toward OH Valley. EUR model depicts
only a minor impact, as wave is weaker and the northern stream
impulse at the same time appears to kept most of pcpn south of area.
So for Wed night to Thurs night, only went with slight chc pops.
Third wave comes from the southern plains on Friday, with the GFS
faster than EUR on approach of the system to IL. Again kept only
slight chc pops because of the slower EUR model trend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 1141 PM CST FRI DEC 12 2014
Problematic aviation forecast for at least the next several hours
across the central Illinois terminals. A large hole in the
expansive low cloud deck across the Midwest continues to spread
east toward the terminals. This hole had previously been expected
to fill in, and the bulk of the forecast guidance suggest this
should still occur. However, confidence in this occurring is
diminishing so have included a TEMPO group to scatter out the
clouds for a time overnight. While the clear area upstream has not
yet seen thick fog problems, good radiational cooling conditions
could allow thicker fog to develop during the clear period. Tried
to cover this potential in the TEMPO group as well. The clouds
should eventually return/fill in areawide and linger through the
remainder of the 06Z TAF valid time. Light south to southwest
winds will prevail through the period.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Bak
SHORT TERM...Barnes
LONG TERM...Goetsch
AVIATION...Bak
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
911 PM CST FRI DEC 12 2014
.SHORT TERM...
257 PM CST
THROUGH SATURDAY...
BIT OF A TRICKY FORECAST THROUGH THE PERIOD REGARDING FOG...DRIZZLE
AND TEMPERATURE TRENDS. AREA IS ON EASTERN SIDE OF ANOMALOUS UPPER
RIDGE...BUT WITH EXPANSIVE SFC RIDGE NOT MOVING MUCH THROUGH THE
PERIOD...MIXING WILL BE VERY SHALLOW. THUS STRONG LOW LEVEL
INVERSION WILL REMAIN IN PLACE...SO WE WONT BE ABLE TO TAP INTO THE
WARMEST AIR ALOFT ON SATURDAY AND WILL KEEP A THICK STRATUS DECK.
HOWEVER...GRADUAL LOW LEVEL WARM AND MOIST ADVECTION SHOULD RESULT
IN STEADY TO SLOWLY RISING TEMPERATURES OVERNIGHT FROM THEIR LATE
AFTERNOON LEVELS IN THE LOWER TO UPPER 30S. HAVE GONE WITH WARMEST
GUIDANCE AND NON-DIURNAL TREND FOR TONIGHTS TEMPERATURES AND
EXPECTING UPPER 30S TO AROUND 40 BY DAYBREAK SATURDAY.
FORECAST SOUNDINGS SHOW WEAK LIFT IN SFC TO ROUGHLY 925 MB
LAYER...WITH POTENTIAL FOR AT LEAST PATCHY DRIZZLE TO DEVELOP FROM
WEST TO EAST OVERNIGHT AND THEN AREA WIDE THROUGH SATURDAY. THINK
THAT LIGHT QPF BEING ADVERTISED BY MOST GUIDANCE IS A BIT
OVERDONE...SO HAVE KEPT POPS BELOW MENTIONABLE BUT CANNOT COMPLETELY
RULE OUT NEEDING ISOLATED POPS. DESPITE THICK STRATUS...VERY LOW
DEWPOINT DEPRESSIONS WILL LIKELY AID IN PATCHY TO AREAS OF FOG THIS
EVENING INTO SATURDAY MORNING...AND PATCHY FOG POSSIBLY LINGERING
INTO SATURDAY AFTERNOON. WITH MILD STARTING POINT ON SATURDAY...DID
NOT MAKE BIG CHANGES TO GOING HIGH TEMPERATURE FORECAST. CONTINUED
GRADUAL LOW LEVEL WARM ADVECTION AND DEWPOINTS RISING INTO THE UPPER
30S-LOWER 40S SUPPORTS GENERALLY MID 40S...WITH A FEW UPPER 40S
POSSIBLE IN SPOTS.
RC
&&
.LONG TERM...
257 PM CST
SUNDAY NIGHT THROUGH FRIDAY...
THE UPPER RIDGE AXIS MOVES OVERHEAD SATURDAY NIGHT...THEN BEGINS TO
SHIFT EASTWARD THROUGH THE DAY ON SUNDAY. THE DEEP UPPER LOW
CURRENTLY OFF THE CALIFORNIA COAST WILL BE MOVING INTO THE
CENTRAL AND SOUTHERN PLAINS SUNDAY AFTERNOON. THE STRONG LARGER
SCALE TEMPERATURE INVERSION IN PLACE ON SATURDAY WEAKENS ON
SUNDAY...THOUGH THERE LOOKS TO BE A WEAKER SECONDARY WARM AIR
ADVECTION SURGE ON SUNDAY AHEAD OF THE UPPER LOW WHICH LOOKS TO
KEEP A LOW LEVEL INVERSION IN PLACE. PLENTY OF LOW CLOUDS AND EVEN
SOME DRIZZLE OVERNIGHT WILL LINGER INTO THE MORNING HOURS YET
AGAIN. WE WILL HAVE A SLIGHTLY BETTER CHANCE GET SOME CLOUD BREAKS
AS A MODEST SURFACE PRESSURE GRADIENT SETS UP BETWEEN THE
DEPARTING HIGH IN THE TENNESSEE VALLEY AND THE LOW IN THE PLAINS.
BUT MORE GETTING MORE OPTIMISTIC IN MORE THAN BROKEN CLOUDS WOULD
BE AMBITIOUS. THAT BEING SAID...DEWPOINTS CONTINUE TO CREEP
UPWARDS INTO AT LEAST THE MID 40S. THEREFORE MANY AREAS STILL HAVE
A DECENT CHANCE TO MAKE A RUN AT 50 DEGREES...ESPECIALLY SOUTH AND
WESTERN AREAS THAT STAND A BETTER CHANCE OF GETTING SOME
ADDITIONAL CLEARING AND EVEN PUSH THE MID 50S. THEN AGAIN SOME
GUIDANCE LIKE THE SREF PLUMES ARE SUGGESTING THAT AREAS NORTH MAY
PEAK OUT IN THE UPPER 40S.
ON MONDAY THE UPPER LOW EJECTS NORTH AND EAST...BEFORE MOVING
OVERHEAD AND OFF TO THE EAST LATER MONDAY NIGHT. SOME MODEL
DISAGREEMENT AS TO HOW FAR NORTH THE LOW WILL MOVE..BUT MODELS
GENERALLY AGREE IN AREAS OF RAINFALL THROUGH THE DAY. HAVE CONTINUED
WITH THE HIGH CHANCE TO LIKELY POPS AS PRECIPITABLE WATER VALUES
INCREASE AHEAD OF THE LOW WITH DECENT MOISTURE ADVECTION...DESPITE
THERMAL PROFILES SUGGEST PRECIPITATION WILL FALL IN THE FORM OF
RAIN.
LATE MONDAY NIGHT INTO TUESDAY THE SURFACE MOVES OVER AND THEN EAST
OF LAKE MICHIGAN AS MODEST HIGH PRESSURE BUILDS SOUTH FROM CENTRAL
CANADA. COLD AIR WILL MOVE IN ON THE BACK SIDE OF THE LOW WITH A
PROGRESSION TO LIGHT RAIN AND POSSIBLY LIGHT SNOW MIXING IN THROUGH
THE DAY. IT ALSO LOOKS TO BE MODESTLY BREEZY ON TUESDAY AS LOW LEVEL
LAPSE RATES IN THE COLD ADVECTION REGIME INCREASE...AND MORE
WINTER-LIKE TEMPERATURES MAKE THEIR RETURN. IT ALSO LOOKS TO REMAIN
CLOUDY AS STRATUS REMAINS TRAPPED UNDER AN INVERSION.
TUESDAY NIGHT WE LOSE THE DEEPER MOISTURE...AND SOME EARLY CLEARING
WILL ALLOW TEMPS TO DIP INTO THE 20S AND WIND CHILLS BACK INTO THE
TEENS. FOR THOSE OF YOU CRAVING FOR MORE SUNSHINE...WEDNESDAY
LOOKS TO BE THE BEST CHANCE AT THIS POINT. A BIT MORE UNCERTAINTY
BEYOND THIS TIME FRAME AS THE MODELS STRUGGLE WITH THE EVOLUTION
OF A TROUGH DIGGING OUT OF CANADA AND A PACIFIC LOW PROGGED TO
MOVE EAST LATER IN THE WEEK. THIS WILL PLAY A ROLE IN HOW COLD IT
GETS MID WEEK AND WHETHER OR NOT THE SOUTHERN STREAM WILL IMPACT
OUR AREA LATE WEEK. THURSDAY IS THE QUESTION MARK DAY AS THE GFS
BRINGS SOME PACIFIC ENERGY THROUGH THE AREA BEFORE HIGH PRESSURE
TAKES CONTROL WHEREAS THE ECMWF/GEM KEEP THINGS DRY THROUGH FRIDAY
BEFORE THE PACIFIC LOW GETS CLOSER TO THE AREA. CONFIDENCE IS
SOMEWHAT LOW DURING THIS TIME FRAME AND HAVE SOME LOWER POPS IN
PLACE.
KMD
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* MVFR OCNL IFR CIGS PROBABLY CLEAR OUT LATE TONIGHT
* MVFR FOG LIKELY TONIGHT WITH POSSIBLE PERIOD OF IFR FOG LATE
* MVFR CIGS COULD RETURN SAT AFTERNOON
IZZI
//DISCUSSION...UPDATED 03Z...
ON TO PLAN B WITH REGARDS TO THE STRATUS FORECAST. SATELLITE
IMAGERY THIS EVENING SHOWS WESTERN EDGE OF THE STRATUS DECK
MARCHING STEADILY EASTWARD AT AROUND 17KT AND SHOWING NO SIGNS UP
UPSTREAM REDEVELOPMENT AFTER SUNSET. ACARS SOUNDINGS FROM THIS
EVENING SHOW WESTERLY WINDS OF 15-20KT BENEATH THE INVERSION WHERE
THE STRATUS RESIDES LENDING INCREASING CONFIDENCE IN SKIES GOING
VFR LATE TONIGHT. MVFR VSBY IN LIGHT FOG LIKELY TO PERSIST AFTER
STRATUS CLEARS OUT AND WILL NEED TO WATCH FOR VSBY DROP TO IFR BUT
AT THIS POINT NOT CONFIDENT SUCH A DROP WILL OCCUR AND PERSIST
GIVEN THE FAIRLY MIXED BOUNDARY LAYER. SECOND BAND OF STRATUS OVER
THE PLAINS THAT IS ADVECTING NORTH ON THE SOUTHERLY FLOW WILL
PROBABLY FLOP EASTWARD INTO OUR AREA SOMETIME LATER SATURDAY
AFTERNOON OR SATURDAY EVENING...WITH LOWERING CIGS AND VSBY
EXPECTED SAT NIGHT.
IZZI
UPDATED 00Z...
EXTENSIVE STRATUS DECK CURRENTLY BLANKETS THE REGION WITH
PREDOMINANTLY MVFR CIGS WITH A FEW POCKETS OF IFR. GUIDANCE AND
CONCEPTUAL MODELS WOULD SUGGEST STRATUS TO BUILD DOWNWARD TO IFR
AND EVENTUALLY LIFR OVERNIGHT...THOUGH RECENT TRENDS HAVE SHOWN
SOME IMPROVEMENT IN CIGS UPSTREAM WHICH LENDS TO SOME UNCERTAINTY
REGARDING HOW CIGS WILL BEHAVE TONIGHT. HAVE OPTED TO MAINTAIN
PREVIOUS FORECAST SHOWING A STEADY DOWNWARD TREND FOR NOW. SHOULD
SEE GRADUAL IMPROVEMENT CIGS SATURDAY WITH MOS GUIDANCE ALL
SHOWING A TRANSITION TO VFR SATURDAY AFTERNOON...GIVEN THAT MOS
GUIDANCE TENDS TO PERFORM FAIRLY WELL IN THESE WINTER STRATUS
SCENARIOS DECIDED TO TREND MORE OPTIMISTIC ON SATURDAY AFTERNOON
WITH CIGS. CONFIDENCE IN CIGS DECREASES WITH TIME...PARTICULARLY
ON SATURDAY AFTERNOON REGARDING THE POTENTIAL CLEARING.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* MEDIUM CONFIDENCE IN CIGS TONIGHT THROUGH SATURDAY
* MEDIUM CONFIDENCE IN VSBY TONIGHT INTO SAT MORNING
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z SUNDAY-12Z FRIDAY...UPDATED 00Z...
SUNDAY...MVFR CIGS PROBABLE...IFR POSSIBLE.
MONDAY...MVFR CIGS PROBABLE...IFR BECOMING LIKELY AT NIGHT. RAIN
DEVELOPING LATE.
TUESDAY...CHANCE OF -RA OR -SN...MAINLY EARLY. MVFR CIGS LIKELY.
WEDNESDAY AND THURSDAY...MVFR CIGS POSSIBLE.
IZZI
&&
.MARINE...
257 PM CST
WINDS WILL REMAIN STEADY OUT OF THE WEST-SOUTHWEST THROUGH SATURDAY
AS HIGH PRESSURE REMAINS PARKED OVER THE OHIO AND MID/LOWER MS
VALLEY AND WEAK LOW PRESSURE MOVES TOWARD JAMES BAY. GENERALLY
LOOKING AT SPEEDS BETWEEN 10 AND 20 KT TONIGHT...BUT THEN THE WEAK
LOW PRESSURE PASSING OVER JAMES BAY SHOULD TIGHTEN GRADIENT SLIGHTLY
AND RESULT IN 15 TO 25 KT WINDS ON THE NORTHERN PORTION OF THE LAKE
ON SATURDAY MORNING AND AFTERNOON. MOIST AIR MASS OVER THE REGION
WILL LIKELY RESULT IN AT LEAST PATCHY FOG OVER THE LAKE TONIGHT AND
SATURDAY. WILL NEED TO MONITOR POTENTIAL FOR MORE WIDESPREAD LOW
VISIBILITY DUE TO THE FOG.
MORE OF THE SAME IS IN PLACE FOR SUNDAY. WINDS START TO BECOME MORE
SOUTHERLY AS LOW PRESSURE MOVES THROUGH THE PLAINS AND HIGH
PRESSURE SHIFTS EAST. ON MONDAY NIGHT LOW PRESSURE EJECTS NORTHEAST
OVER LAKE MICHIGAN WHILE MAINTAINING ITS INTENSITY BEFORE WEAKENING
TUESDAY NIGHT OVER NEW ENGLAND AND SOUTHERN QUEBEC. MEANWHILE MODEST
HIGH PRESSURE SPREADS SOUTHWARD INTO THE UPPER MIDWEST THROUGH THE
WEEK. THE PRESSURE GRADIENT ON TUESDAY IS STRONG ENOUGH TO SUPPORT
WNW WINDS TO 30 KT DURING TUESDAY AND TUESDAY NIGHT BEFORE THE
GRADIENT BEGINS TO SLACKEN FOR THE LATTER HALF OF THE WEEK AS THE
HIGH EXPANDS OVER THE AREA.
RC/KMD
&&
.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:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
905 PM CST Fri Dec 12 2014
.UPDATE...
ISSUED AT 855 PM CST FRI DEC 12 2014
Main concerns this evening, as in recent nights, revolve around
cloud/fog conditions and impact on low temperatures if any clearing
develops. Low level moisture trapped beneath a stout subsidence
inversion has resulted in central and southeast Illinois being
cloudy more often than not the past several days. However, there
have also been several periods with partial or total clearing that
have been tough to forecast/pinpoint. The forecast for the
remainder of the night is no different with respect to this recent
forecast difficulty.
A fairly narrow area of clearing just upstream across parts of
Iowa and Missouri is making rapid progress toward the western
portion of the forecast area. The clear area has been and is
expected to shrink with time as weak WAA persists to the west of
the nearby ridge axis. The weak lift associated with this should
help to keep clouds in place below the subsidence inversion, and
develop clouds where there currently are none. However, can`t
ignore the clearing that is approaching from the west, and that
the latest HRRR suggests will persist for a while longer.
Plan to update the forecast for the latest trends. Most tweaks
will be minor, but will be more notable to the sky condition in the
western portion of the forecast area. Hopefully the developing WAA
will preclude a significant temperature drop in the clear area.
Also have to keep an eye on the clear area resulting in
thicker/possibly dense fog development.
&&
.SHORT TERM...(Tonight)
ISSUED AT 244 PM CST FRI DEC 12 2014
Regional upper air soundings continue to show a strong subsidence
inversion centered at 850mb. Low-level moisture trapped beneath
this inversion has led to overcast conditions across central
Illinois this afternoon. Latest satellite imagery shows plenty of
clearing from the St. Louis area eastward across southern Illinois:
however, it does not appear this clearing will work its way
northward into central Illinois. The far southern KILX CWA from
Flora eastward to Lawrenceville will likely see a period of mostly
sunny skies this afternoon before clouds return this evening.
Forecast soundings for tonight suggest the low clouds will remain in
place, with the main question being whether or not significant fog
will develop. Visibilities dropped to between 1 and 3 miles along
the I-74 corridor early this morning and with the airmass remaining
unchanged/stagnant, see no reason why the same will not happen again
late tonight into tomorrow morning. Current surface observations
from across the area still show at least some restriction to
visibility, so surface-based airmass remains quite moist. With no
appreciable southerly flow developing to help scour out the
moisture, think fog will be widespread across the entire CWA
tonight. Forecast soundings appear to be the most saturated
along/north of I-74, so this is the area most likely to see
potentially dense fog later tonight. Confidence is not high enough
to issue a Dense Fog Advisory, so will only mention areas of fog in
the forecast at this time. Overnight low temperatures will bottom
out in the middle 30s.
&&
.LONG TERM...(Saturday through Friday)
ISSUED AT 244 PM CST FRI DEC 12 2014
The morning upper air showed a strong upper low off the CA coast
this morning, with a 300mb jet of 115 kt on the east side of low,
moving onshore. Exiting upper low over New England was also seen,
with ridge axis over west central plains, starting to move a little
to the east. Moisture channel satellite imagery depicts the west
coast low beginning to move onshore, which will be the system to
gradually move through the southern Rockies and eventually affect
the Midwest by the first of next week. Boundary layer on the back
side of exiting surface high, shows southerly flow of increasing
moisture and warm air to continue to move into Midwest. Result will
be cloudiness and warming temperatures into the weekend. Have added
areas of L-F for most of period until the pcpn reaches the area late
Sunday night. There is deep low level moisture trapped below
inversion and weak lift, so minor periods of drizzle possible.
New EUR brings in pcpn Monday early, little faster than GFS and so
kept qpf similar to previous forecast. POPS in the likely Category
with the closed low forecast to move over state Monday and Monday
night. Pcpn amounts though will be light, as upper low filling by
time it reaches region.
The second system to approach area expected Wednesday night, as a
minor shortwave progged to move toward OH Valley. EUR model depicts
only a minor impact, as wave is weaker and the northern stream
impulse at the same time appears to kept most of pcpn south of area.
So for Wed night to Thurs night, only went with slight chc pops.
Third wave comes from the southern plains on Friday, with the GFS
faster than EUR on approach of the system to IL. Again kept only
slight chc pops because of the slower EUR model trend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
ISSUED AT 552 PM CST FRI DEC 12 2014
Another in our recent series of 00Z TAF periods with extensive
MVFR and local IFR conditions as low level moisture remains trapped
beneath a strong subsidence inversion. Based on current conditions,
and some of the model guidance, it looks like fog may be more of a
problem later tonight and Saturday morning than it has been in
recent days. A weak surface ridge will remain just east of the
central Illinois terminals through the period, supporting light
south to southwest winds.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Bak
SHORT TERM...Barnes
LONG TERM...Goetsch
AVIATION...Bak
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1206 PM CST FRI DEC 12 2014
.UPDATE...
439 AM...EARLY MORNING UPDATE...MADE A LAST MINUTE CHANGE BEFORE
SENDING THE ZONES TO INCLUDE PATCHY LIGHT FREEZING DRIZZLE THROUGH
MID MORNING...MAINLY ACROSS THE NORTHERN/WESTERN CWA. SOME REPORTS
OF FREEZING DRIZZLE FROM DVN AS WELL AS A GLAZE IN WALWORTH COUNTY
IN SOUTHERN WI. NO REPORTS OF ANY ICING YET WITH A FEW CALLS TO
NORTHWEST IL AREAS. AS SLIGHTLY HIGHER DEWPOINTS ADVECT INTO THE
NORTHWEST CWA...POSSIBLE THE SATURATED LAYER WILL GROW DEEP ENOUGH
FOR SOME PATCHY FREEZING DRIZZLE. CONFIDENCE IS LOW BUT IF ANY
DRIZZLE DOES DEVELOP...SOME SLICK SPOTS ARE POSSIBLE. IN
ADDITION...DESPITE THE FOG THUS FAR NOT BEING DENSE...IT HAS
ALLOWED FOR A RATHER HEAVY FROST ON MANY SURFACES. CMS
&&
.SHORT TERM...
TODAY THROUGH SATURDAY NIGHT...
335 AM...FORECAST CONCERNS INCLUDE FOG...TEMPS...CLOUD COVER AND
THEN DRIZZLE POTENTIAL SATURDAY NIGHT.
LOW CLOUDS ARE STEADILY MOVING EAST ACROSS THE AREA EARLY THIS
MORNING. WINDS ARE ALSO SHIFTING A BIT MORE TO THE NORTHWEST AND
GUST BRIEFLY WITH THE LEADING EDGE OF THE CLOUDS. THESE WILL MOVE
INTO INDIANA BY MID MORNING WITH CLOUDY CONDITIONS THIS MORNING.
QUESTION WILL THEN BE WILL THERE BE ANY SCATTERING OR BREAKS IN
THE CLOUDS THIS AFTERNOON. FORECAST SOUNDINGS SHOW A STRONG
INVERSION AND EXPECT THE CLOUDS TO BE TRAPPED BELOW IT AND UNABLE
TO MIX OUT WITH LOW SUN ANGLE. THUS HAVE GONE CLOUDY INTO SATURDAY
MORNING. VISIBILITIES WITH FOG HAVE REMAINED GENERALLY BETWEEN 2SM
AND 5SM MOST AREAS...SO BACKED AWAY FROM THE DENSE FOG MENTION BUT
SOME THICKER FOG UNDER 1SM IS STILL POSSIBLE ACROSS THE NORTHWEST
CWA WHERE DEWPOINTS WILL SLOWLY INCREASE THROUGH THE MID/UPPER 20S
THIS MORNING.
WITH NO SIGNIFICANT WARM AIR ADVECTION AT THE SURFACE TODAY ALONG
WITH THE STRONG INVERSION IN PLACE...HIGH TEMPS TODAY WILL LIKELY
STRUGGLE TO REACH THE UPPER 30S...PROBABLY STAYING IN THE MID 30S
MANY AREAS AND HAVE LOWERED HIGHS A FEW DEGREES. LOWS BACK IN THE
LOWER 30S TONIGHT. EXPECT AT LEAST PATCHY FOG TO DEVELOP TONIGHT
AND WITH SOME INCREASING LOW LEVEL MOISTURE...COULD BE A FEW AREAS
OF THICKER FOG WITH THE POTENTIAL FOR SOME AREAS OF DENSE FOG...
BUT CONFIDENCE REGARDING WIDESPREAD DENSE FOG IS FAIRLY LOW.
AS LOW LEVEL WARM AIR AND MOISTURE SLOWLY BUT STEADILY SPREAD
NORTH ACROSS THE AREA SATURDAY...TEMPS SHOULD WARM INTO THE MID
40S AND LIKELY ONLY DROP INTO THE LOWER 40S...PERHAPS UPPER 30S
SATURDAY NIGHT. SOME FOG WILL LIKELY DEVELOP AGAIN SATURDAY NIGHT
ALONG WITH THE POTENTIAL FOR SOME DRIZZLE. CONFIDENCE ISN/T TOO
HIGH BUT THE SATURATED LAYER CONTINUES TO DEEPEN SATURDAY NIGHT
INTO SUNDAY MORNING. CMS
&&
.LONG TERM...
SUNDAY THROUGH THURSDAY...
335 AM...FORECAST CONCERNS INCLUDE HIGH TEMPS SUNDAY AND MONDAY
AND THEN PRECIP TIMING/TYPE AND TEMP TRENDS MONDAY NIGHT INTO
TUESDAY.
A STRONG UPPER RIDGE WILL SPREAD ACROSS THE REGION SUNDAY AND
SLOWLY MOVE EAST AND WEAKEN MONDAY AS LOW PRESSURE DEVELOPS OVER
THE PLAINS AND MOVES NORTHEAST ACROSS THE LAKES REGION TUESDAY.
HIGH TEMPS BOTH SUNDAY AND MONDAY WILL BE DRIVEN ALMOST COMPLETELY
BY ADVECTION WITH THE POTENTIAL FOR HIGHS WELL INTO THE MID/UPPER
50S SUNDAY AS SUGGESTED BY THE MET GUIDANCE. CONFIDENCE REGARDING
HOW WARM TEMPS WILL GET IS STILL LOW AND MAINTAINED LOWER 50S FOR
NOW. BUT WITH LITTLE DROP IN TEMPS SUNDAY NIGHT...WITH TEMPS
LIKELY STAYING IN THE MID OR EVEN UPPER 40S...MONDAY MAY END UP
BEING AS WARM OR WARMER THAN SUNDAY AND HAVE HIGHS IN THE LOWER
50S THEN AS WELL. IF TRENDS CONTINUE...TEMPS WILL NEED TO BE
BUMPED UP WITH LATER FORECASTS.
LIGHT RAIN WILL BE SPREADING ACROSS THE AREA MONDAY WITH TIMING
DIFFERENCES LARGE ENOUGH NOT TO GET TO FANCY WITH TIMING YET...
BUT COULD HOLD OFF UNTIL THE AFTERNOON WITH A PERIOD OF RAIN INTO
MONDAY EVENING. GFS/ECMWF SHOW COLDER AIR WRAPPING IN FROM THE
WEST/SOUTHWEST LATE MONDAY NIGHT INTO TUESDAY MORNING ON GUSTY
WESTERLY WINDS. BULK OF THE QPF IS EXITING AS THE COLD AIR ARRIVES
SO NOT OVERLY CONCERNED WITH SNOW. TRANSITIONED PRECIP TO A RAIN/
SNOW MIX ON TUESDAY BUT THE THREAT OF ANY PRECIP...REGARDLESS OF
TYPE...COULD END BY MIDDAY TUESDAY. ALSO TRENDED A LITTLE COOLER
WITH TEMPS ON TUESDAY...HOLDING STEADY MIDDAY THEN SLOWLY FALLING
BUT IF TIMING IS FASTER...HIGHS COULD BE IN THE MORNING.
HIGH PRESSURE SPREADS ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY
WITH SOME RATHER SIGNIFICANT TIMING/LOCATION DIFFERENCES WITH THE
NEXT SYSTEM THURSDAY AND FRIDAY AND MAINTAINED JUST SLIGHT CHANCE
POPS FOR THURSDAY FROM THIS DISTANCE. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* IFR CIGS AND IMPROVED VSBY THIS AFTERNOON BUT EXPECT
DETERIORATION BACK TO LIFR CIGS/IFR VIS OVERNIGHT AND EARLY
SATURDAY MORNING WITH DRIZZLE/FOG.
RATZER
//DISCUSSION...UPDATED 18Z...
WEAK RIDGE OF SURFACE HIGH PRESSURE REMAINS FROM THE UPPER
MISSISSIPPI VALLEY SOUTHEAST ACROSS ILLINOIS. LITTLE MOVEMENT OF
THIS FEATURE IS EXPECTED OVER THE NEXT 24 HOURS...THOUGH
SOUTHWESTERLY FLOW TO THE WEST OF THE RIDGE AXIS AND ALOFT ACROSS
THE AREA WILL CONTINUE ADVECT WARMER/MOIST AIR INTO THE REGION.
THIS WILL MAINTAIN A STRONG INVERSION...TRAPPING LOW CLOUDS BELOW.
DIURNAL WARMING HAS ALLOWED LIFR CIGS TO LIFT TO IFR AND THIS
TREND SHOULD CONTINUE THIS AFTERNOON. MOST GUIDANCE DEPICTS LOW
LEVELS SATURATING AGAIN OVERNIGHT TONIGHT...WITH THE POTENTIAL FOR
LIFR CIGS/IFR VSBYS TO AGAIN DEVELOP. LOW LEVEL WARM/MOIST
ADVECTION AND ASSOCIATED WEAK ASCENT WILL ALSO FAVOR REDEVELOPMENT
OF DRIZZLE...WITH ROUGHLY THE 10-16Z PERIOD FAVORED BY MODELS FOR
LOWEST CONDITIONS. WARMING AND MOISTENING SATURDAY...THOUGH SHOULD
AGAIN SEE SOME IMPROVEMENT BACK TO IFR BY LATE MORNING.
WINDS...GENERALLY WEST-NORTHWEST EAST OF THE SFC RIDGE ACROSS
CHICAGO TERMINALS THIS AFTERNOON WITH SPEEDS AROUND 10 KT. WINDS
TO DECREASE AND BACK TO WEST-SOUTHWEST LESS THAN 10 KTS TONIGHT
AND SATURDAY.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN CEILING/VIS TRENDS.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...IFR LIKELY WITH FOG AND POSSIBLE DRIZZLE.
SOUTHWEST WINDS.
SUNDAY...IFR LIKELY. A SLIGHT CHANCE OF RAIN. SOUTH WINDS.
MONDAY...MVFR LIKELY WITH IFR POSSIBLE. CHANCE OF RAIN. SOUTH
WINDS.
TUESDAY...MVFR POSSIBLE. CHANCE OF RAIN OR SNOW. GUSTY NORTHWEST
WINDS.
WEDNESDAY...MVFR POSSIBLE. WEST WINDS.
THURSDAY...MVFR POSSIBLE. SLIGHT CHANCE OF RAIN OR SNOW. SOUTHEAST
WINDS.
MTF
&&
.MARINE...
158 AM CST
A PERSISTENT HIGH PRESSURE RIDGE THAT HAS BEEN DRAPED ACROSS THE
MISSISSIPPI VALLEY WILL HAVE ANOTHER DAY OF MOVING LITTLE BEFORE
DAMPENING AND WEAKENING TO THE SOUTHEAST THIS WEEKEND. THIS
PATTERN WILL MEAN NORTHWEST TO WEST WINDS OVER THE LAKE TODAY
TURNING SOUTHWEST ON SATURDAY. LOW PRESSURE WILL INITIALLY DEVELOP
ACROSS THE NORTHERN PLAINS ON SUNDAY AND MOVE EASTWARD. A STRONGER
LOW ACROSS THE CENTRAL/SOUTHERN PLAINS WILL MOVE TO THE WESTERN
GREAT LAKES AND PHASE WITH THE ORIGINAL LOW. SOUTHERLY WINDS IN
ADVANCE OF THIS WILL INCREASE THOUGH A STABLE PATTERN OVER THE
LAKE WILL HINDER THE WINDS FROM BECOMING TOO STRONG. THE HIGHER
WIND SPEEDS LOOK TO BE BEHIND THE SYSTEM COLD FRONT PASSAGE LIKELY
TO HAPPEN MONDAY NIGHT OR EARLY TUESDAY. THE WEST TO NORTHWEST
WINDS STILL LOOK TO BE IN THE 30 KT ARENA AND THE TIME PERIOD WILL
HAVE TO BE MONITORED FOR POSSIBLE GALES.
IN ADDITION...GRADUALLY INCREASING MOISTURE INTO AND THROUGH THE
WEEKEND WILL LIKELY SUPPORT THE DEVELOPMENT OF FOG OVER THE LAKE AS
DEW POINTS NEAR AND TOP THE WATER TEMPERATURES. SOME OF THIS FOG
COULD END UP BEING DENSE.
MTF
&&
.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:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1152 AM CST Fri Dec 12 2014
.UPDATE...
ISSUED AT 1000 AM CST FRI DEC 12 2014
After a period of clear skies last night, clouds have spread back
across central Illinois this morning. The 12z KILX upper air
sounding showed a 2000-foot saturated layer below 850mb. This
layer is considerably thicker than just 24 hours ago, so potential
for clearing today is slim at best. 12z NAM forecast soundings
show moisture remaining trapped beneath the strong inversion
throughout the day, while HRRR indicates overcast conditions as
well. Based on current satellite imagery that shows breaks in the
overcast south of St. Louis and across far southern Illinois, will
have to monitor the SE KILX CWA for potential breaks this
afternoon. Otherwise it will be a cloudy day across the area. Due
to the clouds and only minimal WAA beneath the surface ridge axis,
have lowered afternoon highs into the middle to upper 30s. Warmest
readings in the lower 40s will be found across the SW CWA around
Jacksonville where WAA will be strongest.
&&
.SHORT TERM...(Today)
ISSUED AT 322 AM CST FRI DEC 12 2014
Satellite imagery and surface observations show a region of low
overcast skies spreading eastward across central IL early this
morning as warm and moist southwesterly flow moves into the area
ahead of the strong low moving through the Southwest. This will
allow high temperatures to increase several degrees today compared
with Thursday, but the extensive cloud cover may hold them down a
few degrees from previous forecast expectations. Expecting
temperatures around 40 degrees most locations. Surface winds will
remain light from the SW today as pressure gradients remain weak in
the vicinity of high pressure centered over the Ohio River Valley.
&&
.LONG TERM...(Tonight through Thursday)
ISSUED AT 322 AM CST FRI DEC 12 2014
Clouds remain a bit of a problem...but most models have them
expanding back over Central Illinois later this evening. Winds
becoming more southerly on the back side of this ridge over the
course of the day, resulting in the slow warm up of the region for
the weekend. Overnight lows only dropping into the 30s...and
Saturday warmer in the upper 40s/near 50. Soundings start to look
more cloudy throughout the weekend, underneath the high pressure in
advance of the approaching storm system. However, forecast
soundings slowly lose the strength of the inversion into Sunday
afternoon, and may need to consider some breaks in the clouds.
Whether from sunshine or aggressive sfc WAA, temps on Sunday
expected to climb into the 50s.
Precip chances return late in the weekend...Sunday night...and into
the first of the work week. Models beginning to resemble one
another with the progression of the upper trof and the surface
system overall, although the NAM is about 6 hrs behind the GFS and
ECMWF. In addition, SuperBlend holding on to pops way too long into
Tuesday. Would pull that entirely but lack of continuity with this
systems forecast and the NAM running slower on approach...will leave
the pops in for Tuesday but keep them low. Tuesday night was
removed altogether. Best chances for rain remain Monday and Monday
night, now easily in the likely category. Forecast confidence
completely disintegrates Wednesday as the pattern shift after
Mondays system lacks any kind of similarity btwn the longer range
models. GFS is showing some ridging at h5 with the low exiting to
the east... and the ECMWF is almost northwesterly flow, with another
impulse following into the trof of the prev system. Keeping pops
very low for Wed night-Thur night until some consensus is reached.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
ISSUED AT 1152 AM CST FRI DEC 12 2014
Latest surface observations indicate IFR ceilings along/northeast
of a KBMI to KCMI line, with MVFR conditions noted elsewhere around
central Illinois. Skies have cleared further southwest in the St.
Louis area and will have to keep an eye on satellite trends to see
if breaks in the overcast can spread northward toward KSPI/KDEC
this afternoon. For now will leave those sites at MVFR, while
gradually raising both KBMI and KCMI to MVFR after 20z. Low clouds
and haze will prevail across the area this evening as airmass
remains stagnant. Forecast soundings and numeric guidance both
suggest areas of fog developing as the night progresses, so have
lowered visbys to between 2 and 4sm accordingly. Will maintain
MVFR ceilings through the night at all sites except KBMI, where
IFR will return. After that, the low overcast/fog will persist
through 18z Sat.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Onton
LONG TERM...HJS
AVIATION...Barnes
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1016 AM CST FRI DEC 12 2014
.UPDATE...
439 AM...EARLY MORNING UPDATE...MADE A LAST MINUTE CHANGE BEFORE
SENDING THE ZONES TO INCLUDE PATCHY LIGHT FREEZING DRIZZLE THROUGH
MID MORNING...MAINLY ACROSS THE NORTHERN/WESTERN CWA. SOME REPORTS
OF FREEZING DRIZZLE FROM DVN AS WELL AS A GLAZE IN WALWORTH COUNTY
IN SOUTHERN WI. NO REPORTS OF ANY ICING YET WITH A FEW CALLS TO
NORTHWEST IL AREAS. AS SLIGHTLY HIGHER DEWPOINTS ADVECT INTO THE
NORTHWEST CWA...POSSIBLE THE SATURATED LAYER WILL GROW DEEP ENOUGH
FOR SOME PATCHY FREEZING DRIZZLE. CONFIDENCE IS LOW BUT IF ANY
DRIZZLE DOES DEVELOP...SOME SLICK SPOTS ARE POSSIBLE. IN
ADDITION...DESPITE THE FOG THUS FAR NOT BEING DENSE...IT HAS
ALLOWED FOR A RATHER HEAVY FROST ON MANY SURFACES. CMS
&&
.SHORT TERM...
TODAY THROUGH SATURDAY NIGHT...
335 AM...FORECAST CONCERNS INCLUDE FOG...TEMPS...CLOUD COVER AND
THEN DRIZZLE POTENTIAL SATURDAY NIGHT.
LOW CLOUDS ARE STEADILY MOVING EAST ACROSS THE AREA EARLY THIS
MORNING. WINDS ARE ALSO SHIFTING A BIT MORE TO THE NORTHWEST AND
GUST BRIEFLY WITH THE LEADING EDGE OF THE CLOUDS. THESE WILL MOVE
INTO INDIANA BY MID MORNING WITH CLOUDY CONDITIONS THIS MORNING.
QUESTION WILL THEN BE WILL THERE BE ANY SCATTERING OR BREAKS IN
THE CLOUDS THIS AFTERNOON. FORECAST SOUNDINGS SHOW A STRONG
INVERSION AND EXPECT THE CLOUDS TO BE TRAPPED BELOW IT AND UNABLE
TO MIX OUT WITH LOW SUN ANGLE. THUS HAVE GONE CLOUDY INTO SATURDAY
MORNING. VISIBILITIES WITH FOG HAVE REMAINED GENERALLY BETWEEN 2SM
AND 5SM MOST AREAS...SO BACKED AWAY FROM THE DENSE FOG MENTION BUT
SOME THICKER FOG UNDER 1SM IS STILL POSSIBLE ACROSS THE NORTHWEST
CWA WHERE DEWPOINTS WILL SLOWLY INCREASE THROUGH THE MID/UPPER 20S
THIS MORNING.
WITH NO SIGNIFICANT WARM AIR ADVECTION AT THE SURFACE TODAY ALONG
WITH THE STRONG INVERSION IN PLACE...HIGH TEMPS TODAY WILL LIKELY
STRUGGLE TO REACH THE UPPER 30S...PROBABLY STAYING IN THE MID 30S
MANY AREAS AND HAVE LOWERED HIGHS A FEW DEGREES. LOWS BACK IN THE
LOWER 30S TONIGHT. EXPECT AT LEAST PATCHY FOG TO DEVELOP TONIGHT
AND WITH SOME INCREASING LOW LEVEL MOISTURE...COULD BE A FEW AREAS
OF THICKER FOG WITH THE POTENTIAL FOR SOME AREAS OF DENSE FOG...
BUT CONFIDENCE REGARDING WIDESPREAD DENSE FOG IS FAIRLY LOW.
AS LOW LEVEL WARM AIR AND MOISTURE SLOWLY BUT STEADILY SPREAD
NORTH ACROSS THE AREA SATURDAY...TEMPS SHOULD WARM INTO THE MID
40S AND LIKELY ONLY DROP INTO THE LOWER 40S...PERHAPS UPPER 30S
SATURDAY NIGHT. SOME FOG WILL LIKELY DEVELOP AGAIN SATURDAY NIGHT
ALONG WITH THE POTENTIAL FOR SOME DRIZZLE. CONFIDENCE ISN/T TOO
HIGH BUT THE SATURATED LAYER CONTINUES TO DEEPEN SATURDAY NIGHT
INTO SUNDAY MORNING. CMS
&&
.LONG TERM...
SUNDAY THROUGH THURSDAY...
335 AM...FORECAST CONCERNS INCLUDE HIGH TEMPS SUNDAY AND MONDAY
AND THEN PRECIP TIMING/TYPE AND TEMP TRENDS MONDAY NIGHT INTO
TUESDAY.
A STRONG UPPER RIDGE WILL SPREAD ACROSS THE REGION SUNDAY AND
SLOWLY MOVE EAST AND WEAKEN MONDAY AS LOW PRESSURE DEVELOPS OVER
THE PLAINS AND MOVES NORTHEAST ACROSS THE LAKES REGION TUESDAY.
HIGH TEMPS BOTH SUNDAY AND MONDAY WILL BE DRIVEN ALMOST COMPLETELY
BY ADVECTION WITH THE POTENTIAL FOR HIGHS WELL INTO THE MID/UPPER
50S SUNDAY AS SUGGESTED BY THE MET GUIDANCE. CONFIDENCE REGARDING
HOW WARM TEMPS WILL GET IS STILL LOW AND MAINTAINED LOWER 50S FOR
NOW. BUT WITH LITTLE DROP IN TEMPS SUNDAY NIGHT...WITH TEMPS
LIKELY STAYING IN THE MID OR EVEN UPPER 40S...MONDAY MAY END UP
BEING AS WARM OR WARMER THAN SUNDAY AND HAVE HIGHS IN THE LOWER
50S THEN AS WELL. IF TRENDS CONTINUE...TEMPS WILL NEED TO BE
BUMPED UP WITH LATER FORECASTS.
LIGHT RAIN WILL BE SPREADING ACROSS THE AREA MONDAY WITH TIMING
DIFFERENCES LARGE ENOUGH NOT TO GET TO FANCY WITH TIMING YET...
BUT COULD HOLD OFF UNTIL THE AFTERNOON WITH A PERIOD OF RAIN INTO
MONDAY EVENING. GFS/ECMWF SHOW COLDER AIR WRAPPING IN FROM THE
WEST/SOUTHWEST LATE MONDAY NIGHT INTO TUESDAY MORNING ON GUSTY
WESTERLY WINDS. BULK OF THE QPF IS EXITING AS THE COLD AIR ARRIVES
SO NOT OVERLY CONCERNED WITH SNOW. TRANSITIONED PRECIP TO A RAIN/
SNOW MIX ON TUESDAY BUT THE THREAT OF ANY PRECIP...REGARDLESS OF
TYPE...COULD END BY MIDDAY TUESDAY. ALSO TRENDED A LITTLE COOLER
WITH TEMPS ON TUESDAY...HOLDING STEADY MIDDAY THEN SLOWLY FALLING
BUT IF TIMING IS FASTER...HIGHS COULD BE IN THE MORNING.
HIGH PRESSURE SPREADS ACROSS THE AREA TUESDAY NIGHT INTO WEDNESDAY
WITH SOME RATHER SIGNIFICANT TIMING/LOCATION DIFFERENCES WITH THE
NEXT SYSTEM THURSDAY AND FRIDAY AND MAINTAINED JUST SLIGHT CHANCE
POPS FOR THURSDAY FROM THIS DISTANCE. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* GRADUALLY IMPROVING FROM LIFR CONDITIONS TO IFR. SOME PATCHY
-FZDZ/-SN AND LOWER CONDITIONS POSSIBLE MAINLY WEST OF CHICAGO
TAFS.
* LIFR CONDITIONS LIKELY TO RETURN LATER TONIGHT.
RATZER
//DISCUSSION...UPDATED 14Z...
LIFR CEIILNGS REMAIN ENTRENCHED ACROSS AREA THIS MORNING...
WITH VISIBILITY GENERALY IFR IN FOG. AREAS OF LIGHT FREEZING
DRIZZLE/SNOW WERE COMPOUNDING VISIBILITY ISSUE HOWEVER...
PARTICULARLY AT KMDW WHERE VIS HAS DROPPED AS LOW AS 1/4-1/2SM AT
TIMES. LOOKING AT RADAR. IT APPEARS THAT SEVERAL POINT SOURCE
INDUSTRIAL PLUMES (SMOKE OR STEAM PLUMES) MAY BE HELPING TO
PRODUCE SOME OF THE LIGHT SNOW REPORTS...INCLUDING THE SNOW AT
KMDW AND ASSOCIATED LOW VISIBILITY. PIREP FROM KMDW INDICATES
CLOUD BASE AT 300 FT AND TOP AT 1600 FT...WHICH MATCHES AMDAR
SOUNDINGS FROM KMDW QUITE WELL.
OVERALL...EXPECT SOME SLOW DIURNAL IMPROVEMENT TO IFR CIG/VIS
CONDITIONS WITH LOSS OF DZ/SN TODAY. HOWEVER...LOW CONIDENCE IN
EVOLUTION OF CURRENT LOW VIS/DZ/SN.
RATZER
PREVIOUS DISCUSSION FROM 12Z...
A HIGH PRESSURE RIDGE CONTINUES JUST EAST OF THE AREA. AROUND
THIS...LIFR CIGS AND IFR VISIBILITY HAVE ENCOMPASSED THE AREA
EARLY THIS MORNING. CONDITIONS MAY DETERIORATE FURTHER THROUGH 13Z-
14Z BEFORE A PROBABLE SLIGHT IMPROVEMENT INTO MID-AFTERNOON.
PATCHY FREEZING DRIZZLE AND EVEN SOME FLURRIES HAVE BEEN REPORTED
IN THE REGION AND CANNOT RULE THESE OUT AT ANY OF THE
AIRPORTS...AS THE PRECIPITATION IS DIFFICULT TO DETECT ON RADAR.
THIS POTENTIAL IS MAINLY EARLY THIS MORNING.
WHILE SOME IMPROVEMENT TO MVFR CIGS IS AS CLOSE AS SOUTHEAST IA
AND WESTERN IL...THE THINKING REMAINS THAT THIS WILL REMAIN WEST
AND SOUTH OF THE AREA TODAY AND TONIGHT. CONDITIONS SHOULD
DETERIORATE AGAIN AFTER DARK TONIGHT THOUGH HOW QUICKLY IS
DIFFICULT TO SAY GIVEN THE INHERENT STRATUS DECK. THERE WILL AGAIN
BE A CHANCE FOR FREEZING DRIZZLE OR DRIZZLE LATER TONIGHT INTO
EARLY SATURDAY MORNING.
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM THAT CIGS WILL REMAIN MAINLY IFR INTO THIS AFTERNOON.
* MEDIUM IN LIFR CONDITIONS RETURNING TONIGHT. LOW IN TIMING.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...IFR LIKELY WITH FOG AND POSSIBLE DRIZZLE.
SOUTHWEST WINDS.
SUNDAY...IFR LIKELY. A SLIGHT CHANCE OF RAIN. SOUTH WINDS.
MONDAY...MVFR LIKELY WITH IFR POSSIBLE. CHANCE OF RAIN. SOUTH
WINDS.
TUESDAY...MVFR POSSIBLE. CHANCE OF RAIN OR SNOW. GUSTY NORTHWEST
WINDS.
WEDNESDAY...MVFR POSSIBLE. WEST WINDS.
THURSDAY...MVFR POSSIBLE. SLIGHT CHANCE OF RAIN OR SNOW. SOUTHEAST
WINDS.
MTF
&&
.MARINE...
158 AM CST
A PERSISTENT HIGH PRESSURE RIDGE THAT HAS BEEN DRAPED ACROSS THE
MISSISSIPPI VALLEY WILL HAVE ANOTHER DAY OF MOVING LITTLE BEFORE
DAMPENING AND WEAKENING TO THE SOUTHEAST THIS WEEKEND. THIS
PATTERN WILL MEAN NORTHWEST TO WEST WINDS OVER THE LAKE TODAY
TURNING SOUTHWEST ON SATURDAY. LOW PRESSURE WILL INITIALLY DEVELOP
ACROSS THE NORTHERN PLAINS ON SUNDAY AND MOVE EASTWARD. A STRONGER
LOW ACROSS THE CENTRAL/SOUTHERN PLAINS WILL MOVE TO THE WESTERN
GREAT LAKES AND PHASE WITH THE ORIGINAL LOW. SOUTHERLY WINDS IN
ADVANCE OF THIS WILL INCREASE THOUGH A STABLE PATTERN OVER THE
LAKE WILL HINDER THE WINDS FROM BECOMING TOO STRONG. THE HIGHER
WIND SPEEDS LOOK TO BE BEHIND THE SYSTEM COLD FRONT PASSAGE LIKELY
TO HAPPEN MONDAY NIGHT OR EARLY TUESDAY. THE WEST TO NORTHWEST
WINDS STILL LOOK TO BE IN THE 30 KT ARENA AND THE TIME PERIOD WILL
HAVE TO BE MONITORED FOR POSSIBLE GALES.
IN ADDITION...GRADUALLY INCREASING MOISTURE INTO AND THROUGH THE
WEEKEND WILL LIKELY SUPPORT THE DEVELOPMENT OF FOG OVER THE LAKE AS
DEW POINTS NEAR AND TOP THE WATER TEMPERATURES. SOME OF THIS FOG
COULD END UP BEING DENSE.
MTF
&&
.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:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1000 AM CST Fri Dec 12 2014
.UPDATE...
ISSUED AT 1000 AM CST FRI DEC 12 2014
After a period of clear skies last night, clouds have spread back
across central Illinois this morning. The 12z KILX upper air
sounding showed a 2000-foot saturated layer below 850mb. This
layer is considerably thicker than just 24 hours ago, so potential
for clearing today is slim at best. 12z NAM forecast soundings
show moisture remaining trapped beneath the strong inversion
throughout the day, while HRRR indicates overcast conditions as
well. Based on current satellite imagery that shows breaks in the
overcast south of St. Louis and across far southern Illinois, will
have to monitor the SE KILX CWA for potential breaks this
afternoon. Otherwise it will be a cloudy day across the area. Due
to the clouds and only minimal WAA beneath the surface ridge axis,
have lowered afternoon highs into the middle to upper 30s. Warmest
readings in the lower 40s will be found across the SW CWA around
Jacksonville where WAA will be strongest.
&&
.SHORT TERM...(Today)
ISSUED AT 322 AM CST FRI DEC 12 2014
Satellite imagery and surface observations show a region of low
overcast skies spreading eastward across central IL early this
morning as warm and moist southwesterly flow moves into the area
ahead of the strong low moving through the Southwest. This will
allow high temperatures to increase several degrees today compared
with Thursday, but the extensive cloud cover may hold them down a
few degrees from previous forecast expectations. Expecting
temperatures around 40 degrees most locations. Surface winds will
remain light from the SW today as pressure gradients remain weak in
the vicinity of high pressure centered over the Ohio River Valley.
&&
.LONG TERM...(Tonight through Thursday)
ISSUED AT 322 AM CST FRI DEC 12 2014
Clouds remain a bit of a problem...but most models have them
expanding back over Central Illinois later this evening. Winds
becoming more southerly on the back side of this ridge over the
course of the day, resulting in the slow warm up of the region for
the weekend. Overnight lows only dropping into the 30s...and
Saturday warmer in the upper 40s/near 50. Soundings start to look
more cloudy throughout the weekend, underneath the high pressure in
advance of the approaching storm system. However, forecast
soundings slowly lose the strength of the inversion into Sunday
afternoon, and may need to consider some breaks in the clouds.
Whether from sunshine or aggressive sfc WAA, temps on Sunday
expected to climb into the 50s.
Precip chances return late in the weekend...Sunday night...and into
the first of the work week. Models beginning to resemble one
another with the progression of the upper trof and the surface
system overall, although the NAM is about 6 hrs behind the GFS and
ECMWF. In addition, SuperBlend holding on to pops way too long into
Tuesday. Would pull that entirely but lack of continuity with this
systems forecast and the NAM running slower on approach...will leave
the pops in for Tuesday but keep them low. Tuesday night was
removed altogether. Best chances for rain remain Monday and Monday
night, now easily in the likely category. Forecast confidence
completely disintegrates Wednesday as the pattern shift after
Mondays system lacks any kind of similarity btwn the longer range
models. GFS is showing some ridging at h5 with the low exiting to
the east... and the ECMWF is almost northwesterly flow, with another
impulse following into the trof of the prev system. Keeping pops
very low for Wed night-Thur night until some consensus is reached.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 547 AM CST FRI DEC 12 2014
MVFR conditions will be predominant across central and southeast
Illinois for the next 24 hours. An area of MVFR with locally IFR
ceilings will spread eastward to the IL/IN border shortly after
12Z, and remain over the area for the next few days. In addition,
MVFR visibilities will be common until around 16Z. By late
afternoon, warming temperatures may result in some breaks in the
overcast ceilings, but these should end shortly after sunset.
Winds generally W-SW 6 Kts or less for the next 24 hours.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Onton
LONG TERM...HJS
AVIATION...Onton
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
545 PM EST SAT DEC 13 2014
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 336 PM EST SAT DEC 13 2014
MAINLY CLOUDY CONDITIONS WILL CONTINUE THROUGH THE WEEKEND. LOW
PRESSURE TRACKING INTO THE GREAT LAKES WILL BRING RAIN INTO CENTRAL
INDIANA MONDAY THROUGH TUESDAY. HIGH PRESSURE WILL THEN SPREAD INTO
THE OHIO VALLEY WITH DRY SEASONABLE WEATHER THROUGH MUCH OF THE
REMAINDER OF THE WORKWEEK. A STRONGER LOW PRESSURE TRACKING INTO THE
REGION FRIDAY AND SATURDAY WILL BRING THE POTENTIAL FOR WINTRY
PRECIPITATION ALONG WITH COLDER TEMPERATURES.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 336 PM EST SAT DEC 13 2014
STRATUS DECK REMAINS RELATIVELY SOLID OVER MUCH OF THE REGION AS OF
20Z...BUT MOTHER NATURE HAS HAD SOME TRICKS UP HER SLEEVE WITH
RESPECT TO THE CLOUDS TO OUR NORTH AND WEST. DESPITE LAPS SOUNDINGS
OVER NORTHWEST INDIANA INDICATING SATURATED CONDITIONS UP TO AROUND
900MB UNDER A SHARP INVERSION...HAVE SEEN A SUCKERHOLE DEVELOP AND
EXPAND SOUTH OVER THE LAST FEW HOURS WITH SOME SUNSHINE INTO FAR
NORTHERN COUNTIES AS OF 20Z. DESPITE THE CLOUDS ELSEWHERE...MANY
LOCATIONS WERE EXPERIENCING THEIR WARMEST TEMPS FOR THE MONTH WITH
20Z READINGS IN THE MID/UPPER 40S.
FIRST ISSUE FOCUSES ON HOW EXPANSIVE THE SUCKERHOLE OVER NORTHERN
INDIANA AND SOUTH CENTRAL ILLINOIS CAN BECOME PRIOR TO SUNSET. RAP
DOES SEEM TO BE CAPTURING THE SLIGHTLY LOWER RH VALUES IN THE
950-925MB LAYER IN THE LOCATIONS WHERE THE SUN HAS BROKEN OUT. AS
THE TEMPERATURE INVERSION STRENGTHENS INTO THE EVENING AS ADVERTISED
BY THE MODEL SOUNDINGS WOULD EXPECT THE STRATUS TO REESTABLISH AND
THICKEN...AND THIS IS SUPPORTED BY THE RAP RH PROGS. NOT SURE IF ANY
SUN CAN POKE OUT AS FAR SOUTH AS THE INDY METRO...BUT LOCATIONS
NORTH/WEST OF THE CITY MAY SEE BRIEF GLIMPSES OF THE SUN OVER THE
NEXT HOUR OR SO.
AFTER SUNSET...AM TRENDING BACK TO CLOUDY SKIES WITH POTENTIAL FOR
PATCHY FOG AND DRIZZLE TO DEVELOP PRIMARILY AFTER MIDNIGHT AS THE
MOISTURE LAYER UNDERNEATH THE INVERSION DEEPENS AND RISES. THERE IS
ALSO A HINT OF SUBTLE INSTABILITY UNDER THE INVERSION WHICH MAY
ASSIST IN THE DRIZZLE POTENTIAL AS WELL.
TEMPS...TRENDED MUCH CLOSER TO THE WARMER METMOS WITH CLOUDS/PATCHY
DRIZZLE OVERNIGHT AND WARM ADVECTION PERSISTENCE IN THE LOW LEVELS.
EXPECT LOWS MAINLY IN THE UPPER 30S TO LOWER 40S.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 336 PM EST SAT DEC 13 2014
FORECAST CHALLENGES FOCUS ON PRECIP CHANCES MONDAY AND TUESDAY AND
TEMPS THROUGHOUT THE SHORT TERM.
THE LOW LEVEL TEMPERATURE INVERSION REMAINS STRONG THROUGH SUNDAY
WITH THE SURFACE HIGH CENTERED TO THE SOUTHEAST AND THE UPPER RIDGE
AXIS OVER THE OHIO VALLEY. THE DEEPER SATURATED LAYER UNDER THE
INVERSION AND ARRIVAL OF WEAK ISENTROPIC LIFT THROUGH THE 290K LAYER
SHOULD BE ENOUGH TO MAINTAIN THE PATCHY FOG AND DRIZZLE THROUGH THE
MORNING. WHILE STRATUS WILL LINGER ALL DAY...FOG AND DRIZZLE IS
EXPECTED TO DIMINISH DURING THE AFTERNOON AS THE INVERSION WEAKENS
WITH TEMPS COOLING SLIGHTLY AND RH VALUES INCREASING ABOVE THE
BOUNDARY LAYER.
THE SURFACE HIGH AND UPPER RIDGE AXIS WILL DRIFT EAST SUNDAY NIGHT
WITH A PREDOMINANT S/SE FLOW DEVELOPING AS LOW PRESSURE PINWHEELS
OUT OF THE CENTRAL PLAINS. SLIGHTLY DRIER AIR INFILTRATING THE NEAR
SURFACE LAYER MAY ALLOW FOR SOME SCATTERING OF THE STRATUS MONDAY
MORNING...ESPECIALLY OVER SOUTHERN COUNTIES. ANY BREAKS WILL QUICKLY
DISAPPEAR BY MIDDAY AS A STRONGER SURGE OF ISENTROPIC LIFT AND DEEP
MOISTURE ADVECT INTO THE REGION AHEAD OF THE LOW.
LIGHT RAIN WILL INCREASE IN COVERAGE MONDAY AFTERNOON AND EVENING AS
THE LOW TRACKS INTO THE LOWER GREAT LAKES. THE ISENTROPIC LIFT AND
DIFFLUENCE ALOFT DURING THE AFTERNOON WILL BE THE INITIAL CATALYSTS
FOR RAIN WITH A 40KT 850MB JET LIKELY BRINGING MORE EXPANSIVE
RAINFALL IN MONDAY NIGHT. WILL CONTINUE WITH LIKELY POPS ACROSS THE
ENTIRE FORECAST AREA AS A RESULT. PRECIP AMOUNTS WILL BE LIGHT...
GENERALLY AT A QUARTER INCH OR LESS BY TUESDAY. STRATUS WILL LINGER
TUESDAY WITH SCATTERED LIGHT RAIN SHOWERS GRADUALLY ENDING FROM WEST
TO EAST AS FORCING ALOFT SHIFTS EAST.
TEMPS...STILL PREFER TO LEAN CLOSER TO THE RAW SURFACE TEMPS OFF THE
MODELS VERSUS WARMER MOS GUIDANCE FOR HIGHS SUNDAY AND MONDAY.
CONSIDERING TEMP PERFORMANCE TODAY AND EXPECTATION OF WARMER AIR IN
THE 925-950MB LAYER...UPPER 40S EAST AND LOWER 50S WEST IS THE
THINKING FOR SUNDAY. EXPECT HIGHS GENERALLY A DEGREE OR TWO COOLER
MONDAY WITH THE RAIN ARRIVING. TUESDAY HIGHS ARE EXPECTED IN THE
MORNING WITH SLOWLY FALLING TEMPS IN THE AFTERNOON AS COLD ADVECTION
ESTABLISHES. TRENDED TOWARDS WARMER METMOS SUNDAY NIGHT THEN TOOK A
MODEL BLEND FOR MONDAY NIGHT.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 238 PM EST SAT DEC 13 2014
FOR MOST OF THE PERIOD MODELS ARE CLOSE ENOUGH TO ACCEPT THE
SUPERBLEND INITIALIZATION. HOWEVER THERE ARE SOME DIFFERENCES IN
HANDLING OF SYSTEM IMPACTING CENTRAL INDIANA NEXT WEEKEND. WITH THE
UNCERTAINTY IN TIMING AND LOCATION...STAYED CLOSE TO THE
INITIALIZATION HERE AS WELL.
GENERALLY DRY CONDITIONS CAN BE EXPECTED THROUGH THURSDAY NIGHT WITH
HIGH PRESSURE BUILDING IN FROM THE NORTH. FOR FRIDAY...EVEN THE
FASTER GFS SHOWS PRECIPITATION ARRIVING IN THE AFTERNOON...SO
DELAYED POPS UNTIL THEN.
FRIDAY NIGHT AND SATURDAY IS WHERE THE UNCERTAINTY REALLY RAMPS UP.
GFS BRINGS PRECIPITATION THROUGH FASTER WITH A WEAKER UPPER SYSTEM
WHILE ECMWF IS SLOWER AND STRONGER. DECIDED TO KEEP JUST CHANCE POPS
BUT GO HIGHEST IN THE SOUTH WHERE BOTH MODELS AGREE HIGHER
PRECIPITATION AMOUNTS WOULD BE.
BOTH MODELS ARE SHOWING SOME ACCUMULATING SNOW ACROSS PARTS OF THE
AREA FRIDAY NIGHT INTO SATURDAY. WILL CONTINUE TO MONITOR...BUT
STORM TRACK IS STILL QUITE UNCERTAIN.
&&
.AVIATION /DISCUSSION FOR THE 14/0000Z TAF ISSUANCE/...
ISSUED AT 545 PM EST SAT DEC 13 2014
MVFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH POSSIBLE LOWER
CONDITIONS LATE TONIGHT THROUGH MID MORNING SUNDAY.
MVFR CEILINGS WILL BE THE RULE AS A LOW LEVEL INVERSION CONTINUES
ACROSS OUR REGION. MODEL SOUNDINGS INDICATE CEILINGS WILL LOWER
OVERNIGHT AS LIGHT FOG SLOWLY INCREASES. CEILINGS WILL BE MOSTLY 2
TO 3 THOUSAND THIS EVENING GRADUALLY LOWERING TO 1 THOUSAND TO 15
HUNDRED FEET VERY LATE TONIGHT. THERE MAY BE SOME DRIZZLE AS WELL.
WOULD NOT BE SURPRISED TO SEE IFR CEILINGS VISIBILITY APPEAR FOR A
PERIOD SUNDAY MORNING.
OTHERWISE...SOME IMPROVEMENT EXPECTED BY MIDDAY SUNDAY BUT STILL
REMAINING MVFR CEILINGS. SOUTHWEST WINDS 5 TO 8 KNOTS TONIGHT WILL
BECOME SOUTH BY MIDDAY SUNDAY.
..BUT NOT CONFIDENT ENOUGH TO ADD AT THIS TIME.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...50
AVIATION...JH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
336 PM EST SAT DEC 13 2014
.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED
BELOW.
&&
.SYNOPSIS...
ISSUED AT 336 PM EST SAT DEC 13 2014
MAINLY CLOUDY CONDITIONS WILL CONTINUE THROUGH THE WEEKEND. LOW
PRESSURE TRACKING INTO THE GREAT LAKES WILL BRING RAIN INTO CENTRAL
INDIANA MONDAY THROUGH TUESDAY. HIGH PRESSURE WILL THEN SPREAD INTO
THE OHIO VALLEY WITH DRY SEASONABLE WEATHER THROUGH MUCH OF THE
REMAINDER OF THE WORKWEEK. A STRONGER LOW PRESSURE TRACKING INTO THE
REGION FRIDAY AND SATURDAY WILL BRING THE POTENTIAL FOR WINTRY
PRECIPITATION ALONG WITH COLDER TEMPERATURES.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 336 PM EST SAT DEC 13 2014
STRATUS DECK REMAINS RELATIVELY SOLID OVER MUCH OF THE REGION AS OF
20Z...BUT MOTHER NATURE HAS HAD SOME TRICKS UP HER SLEEVE WITH
RESPECT TO THE CLOUDS TO OUR NORTH AND WEST. DESPITE LAPS SOUNDINGS
OVER NORTHWEST INDIANA INDICATING SATURATED CONDITIONS UP TO AROUND
900MB UNDER A SHARP INVERSION...HAVE SEEN A SUCKERHOLE DEVELOP AND
EXPAND SOUTH OVER THE LAST FEW HOURS WITH SOME SUNSHINE INTO FAR
NORTHERN COUNTIES AS OF 20Z. DESPITE THE CLOUDS ELSEWHERE...MANY
LOCATIONS WERE EXPERIENCING THEIR WARMEST TEMPS FOR THE MONTH WITH
20Z READINGS IN THE MID/UPPER 40S.
FIRST ISSUE FOCUSES ON HOW EXPANSIVE THE SUCKERHOLE OVER NORTHERN
INDIANA AND SOUTH CENTRAL ILLINOIS CAN BECOME PRIOR TO SUNSET. RAP
DOES SEEM TO BE CAPTURING THE SLIGHTLY LOWER RH VALUES IN THE
950-925MB LAYER IN THE LOCATIONS WHERE THE SUN HAS BROKEN OUT. AS
THE TEMPERATURE INVERSION STRENGTHENS INTO THE EVENING AS ADVERTISED
BY THE MODEL SOUNDINGS WOULD EXPECT THE STRATUS TO REESTABLISH AND
THICKEN...AND THIS IS SUPPORTED BY THE RAP RH PROGS. NOT SURE IF ANY
SUN CAN POKE OUT AS FAR SOUTH AS THE INDY METRO...BUT LOCATIONS
NORTH/WEST OF THE CITY MAY SEE BRIEF GLIMPSES OF THE SUN OVER THE
NEXT HOUR OR SO.
AFTER SUNSET...AM TRENDING BACK TO CLOUDY SKIES WITH POTENTIAL FOR
PATCHY FOG AND DRIZZLE TO DEVELOP PRIMARILY AFTER MIDNIGHT AS THE
MOISTURE LAYER UNDERNEATH THE INVERSION DEEPENS AND RISES. THERE IS
ALSO A HINT OF SUBTLE INSTABILITY UNDER THE INVERSION WHICH MAY
ASSIST IN THE DRIZZLE POTENTIAL AS WELL.
TEMPS...TRENDED MUCH CLOSER TO THE WARMER METMOS WITH CLOUDS/PATCHY
DRIZZLE OVERNIGHT AND WARM ADVECTION PERSISTENCE IN THE LOW LEVELS.
EXPECT LOWS MAINLY IN THE UPPER 30S TO LOWER 40S.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 336 PM EST SAT DEC 13 2014
FORECAST CHALLENGES FOCUS ON PRECIP CHANCES MONDAY AND TUESDAY AND
TEMPS THROUGHOUT THE SHORT TERM.
THE LOW LEVEL TEMPERATURE INVERSION REMAINS STRONG THROUGH SUNDAY
WITH THE SURFACE HIGH CENTERED TO THE SOUTHEAST AND THE UPPER RIDGE
AXIS OVER THE OHIO VALLEY. THE DEEPER SATURATED LAYER UNDER THE
INVERSION AND ARRIVAL OF WEAK ISENTROPIC LIFT THROUGH THE 290K LAYER
SHOULD BE ENOUGH TO MAINTAIN THE PATCHY FOG AND DRIZZLE THROUGH THE
MORNING. WHILE STRATUS WILL LINGER ALL DAY...FOG AND DRIZZLE IS
EXPECTED TO DIMINISH DURING THE AFTERNOON AS THE INVERSION WEAKENS
WITH TEMPS COOLING SLIGHTLY AND RH VALUES INCREASING ABOVE THE
BOUNDARY LAYER.
THE SURFACE HIGH AND UPPER RIDGE AXIS WILL DRIFT EAST SUNDAY NIGHT
WITH A PREDOMINANT S/SE FLOW DEVELOPING AS LOW PRESSURE PINWHEELS
OUT OF THE CENTRAL PLAINS. SLIGHTLY DRIER AIR INFILTRATING THE NEAR
SURFACE LAYER MAY ALLOW FOR SOME SCATTERING OF THE STRATUS MONDAY
MORNING...ESPECIALLY OVER SOUTHERN COUNTIES. ANY BREAKS WILL QUICKLY
DISAPPEAR BY MIDDAY AS A STRONGER SURGE OF ISENTROPIC LIFT AND DEEP
MOISTURE ADVECT INTO THE REGION AHEAD OF THE LOW.
LIGHT RAIN WILL INCREASE IN COVERAGE MONDAY AFTERNOON AND EVENING AS
THE LOW TRACKS INTO THE LOWER GREAT LAKES. THE ISENTROPIC LIFT AND
DIFFLUENCE ALOFT DURING THE AFTERNOON WILL BE THE INITIAL CATALYSTS
FOR RAIN WITH A 40KT 850MB JET LIKELY BRINGING MORE EXPANSIVE
RAINFALL IN MONDAY NIGHT. WILL CONTINUE WITH LIKELY POPS ACROSS THE
ENTIRE FORECAST AREA AS A RESULT. PRECIP AMOUNTS WILL BE LIGHT...
GENERALLY AT A QUARTER INCH OR LESS BY TUESDAY. STRATUS WILL LINGER
TUESDAY WITH SCATTERED LIGHT RAIN SHOWERS GRADUALLY ENDING FROM WEST
TO EAST AS FORCING ALOFT SHIFTS EAST.
TEMPS...STILL PREFER TO LEAN CLOSER TO THE RAW SURFACE TEMPS OFF THE
MODELS VERSUS WARMER MOS GUIDANCE FOR HIGHS SUNDAY AND MONDAY.
CONSIDERING TEMP PERFORMANCE TODAY AND EXPECTATION OF WARMER AIR IN
THE 925-950MB LAYER...UPPER 40S EAST AND LOWER 50S WEST IS THE
THINKING FOR SUNDAY. EXPECT HIGHS GENERALLY A DEGREE OR TWO COOLER
MONDAY WITH THE RAIN ARRIVING. TUESDAY HIGHS ARE EXPECTED IN THE
MORNING WITH SLOWLY FALLING TEMPS IN THE AFTERNOON AS COLD ADVECTION
ESTABLISHES. TRENDED TOWARDS WARMER METMOS SUNDAY NIGHT THEN TOOK A
MODEL BLEND FOR MONDAY NIGHT.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 238 PM EST SAT DEC 13 2014
FOR MOST OF THE PERIOD MODELS ARE CLOSE ENOUGH TO ACCEPT THE
SUPERBLEND INITIALIZATION. HOWEVER THERE ARE SOME DIFFERENCES IN
HANDLING OF SYSTEM IMPACTING CENTRAL INDIANA NEXT WEEKEND. WITH THE
UNCERTAINTY IN TIMING AND LOCATION...STAYED CLOSE TO THE
INITIALIZATION HERE AS WELL.
GENERALLY DRY CONDITIONS CAN BE EXPECTED THROUGH THURSDAY NIGHT WITH
HIGH PRESSURE BUILDING IN FROM THE NORTH. FOR FRIDAY...EVEN THE
FASTER GFS SHOWS PRECIPITATION ARRIVING IN THE AFTERNOON...SO
DELAYED POPS UNTIL THEN.
FRIDAY NIGHT AND SATURDAY IS WHERE THE UNCERTAINTY REALLY RAMPS UP.
GFS BRINGS PRECIPITATION THROUGH FASTER WITH A WEAKER UPPER SYSTEM
WHILE ECMWF IS SLOWER AND STRONGER. DECIDED TO KEEP JUST CHANCE POPS
BUT GO HIGHEST IN THE SOUTH WHERE BOTH MODELS AGREE HIGHER
PRECIPITATION AMOUNTS WOULD BE.
BOTH MODELS ARE SHOWING SOME ACCUMULATING SNOW ACROSS PARTS OF THE
AREA FRIDAY NIGHT INTO SATURDAY. WILL CONTINUE TO MONITOR...BUT
STORM TRACK IS STILL QUITE UNCERTAIN.
&&
.AVIATION /DISCUSSION FOR THE 13/2100Z TAF UPDATE/...
ISSUED AT 320 PM EST SAT DEC 13 2014
UPDATE...
NO CHANGES.
PREVIOUS DISCUSSION...
MVFR CONDITIONS EXPECTED THROUGH THE PERIOD.
CEILINGS CONTINUE TO SLOWLY RISE...AND SOME HOLES IN THE OVERCAST
DEVELOPING IN ILLINOIS. HOWEVER...CEILINGS SHOULD REMAIN
PREDOMINANTLY HIGH END MVFR AS INVERSION REMAINS IN PLACE. THUS EVEN
THOUGH PERIODS OF VFR ARE POSSIBLE THIS AFTERNOON...KEPT IT SIMPLE
WITH A HIGH END MVFR FORECAST.
TONIGHT INVERSION LOWERS SO LOWERED CEILINGS AND DEVELOPED SOME MVFR
FOG AS WELL. WENT BELOW 2000FT BY SUNRISE SUNDAY AND ADDED SOME
DRIZZLE. WOULD NOT BE SURPRISED TO SEE IFR CEILINGS APPEAR FOR A
PERIOD SUNDAY MORNING...BUT NOT CONFIDENT ENOUGH TO ADD AT THIS
TIME.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...50
AVIATION...50/TDUD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
920 PM EST FRI DEC 12 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 338 PM EST FRI DEC 12 2014
DESPITE HIGH PRESSURE OVER THE REGION...TRAPPED LOW LEVEL MOISTURE
WILL KEEP CLOUDY SKIES WITH OCCASIONAL FOG AND DRIZZLE THROUGH THE
WEEKEND. RAIN WILL DEVELOP MONDAY THROUGH TUESDAY AS LOW PRESSURE
TRACKS INTO THE GREAT LAKES. MAINLY DRY WEATHER WILL RETURN FOR MUCH
OF THE REST OF THE WEEK ALONG WITH SEASONABLY COOL TEMPERATURES.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 338 PM EST FRI DEC 12 2014
STRATUS DECK AS OF 20Z HAS ENCOMPASSED MOST OF THE FORECAST
AREA...WITH JUST FAR EASTERN COUNTIES STILL ENJOYING SUNSHINE.
CLEARING IS ALSO ATTEMPTING TO SNEAK INTO THE LOWER WABASH VALLEY.
TEMPS HAVE BEEN KEPT DOWN AS A RESULT OF THE CLOUD DECK AND PATCHY
FOG IN SPOTS. TEMPS LARGELY REMAINED IN THE LOWER/MID 30S.
PRIMARY CHALLENGE FOR TONIGHT FOCUSES ON FOG POTENTIAL AS STRATUS
DECK SETTLES IN OVER CENTRAL INDIANA. CONTINUE TO LEAN ON THE RAP
WHICH HAS CAPTURED THE CLOUD DECK EXPANSION WELL SO FAR TODAY. LOWER
RH VALUES IN THE 925-950MB RANGE OVER SOUTHERN ILLINOIS THIS
AFTERNOON IN VICINITY OF THE CURRENT AREA OF CLEARING. SHOULD SEE
THIS CLEARING POKE INTO FAR SOUTHWEST COUNTIES OVER THE NEXT FEW
HOURS. LOW LEVEL FLOW PROGGED TO GRADUALLY VEER TO THE W/NW THIS
EVENING...AND THIS WILL FORCE THE CLEARING BACK TO THE SOUTHWEST
WITH THE STRATUS REESTABLISHING OVER THE LOWER WABASH VALLEY.
MODEL SOUNDINGS INDICATE THE SHALLOW INVERSION WILL STRENGTHEN
OVERNIGHT BELOW 2500FT...SUPPORTING THICK MVFR/IFR STRATUS AND FOG
DEVELOPMENT WITH A RELATIVELY STAGNANT AIRMASS OVERHEAD. LIGHT WINDS
SHOULD KEEP VISIBILITIES FROM GETTING WAY DOWN...BUT DO EXPECT AREAS
OF 2-3SM DEVELOPING OVERNIGHT WITH POCKETS OF LOWER VISIBILITIES.
TEMPS...HAVE TRENDED WITH THE RAP HOURLIES OVERNIGHT. LOWS ARE
EXPECTED DURING THE EVENING WITH STEADY OR SLOWLY RISING TEMPS
PRIMARILY IN THE 30S THEREAFTER. SUBFREEZING TEMPS MAY LINGER OVER
NORTHERN COUNTIES FOR MUCH OF THE NIGHT BEFORE WARMING TO OR ABOVE
32F. SHOULD ANY THICKER FOG DEVELOP...FREEZING FOG COULD BE A
POTENTIAL CONCERN. WILL NEED TO MONITOR TEMP/FOG TRENDS THROUGH THE
NIGHT.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 338 PM EST FRI DEC 12 2014
FORECAST CHALLENGES FOCUS ON FOG...DRIZZLE AND TEMPS AS CLOUDS
RETURN FOR AN EXTENDED STAY ACROSS THE HOOSIER STATE. RAIN ARRIVES
MONDAY WITH THE APPROACH OF LOW PRESSURE. THE SUN HAS AGAIN TAKEN AN
EXTENDED HOLIDAY.
HIGHLY AMPLIFIED FLOW ALOFT ACROSS THE LOWER 48 WITH A DEEP UPPER
LOW OVER NEW ENGLAND AND AN ANOMALOUSLY STRONG RIDGE OVER THE
CENTRAL PLAINS. THE UPPER LOW WILL SLOWLY DRIFT EAST INTO THE
ATLANTIC OVER THE WEEKEND WITH THE RIDGE GRADUALLY DEAMPLIFYING OVER
THE OHIO VALLEY. SURFACE HIGH PRESSURE WILL REMAIN A DOMINANT
INFLUENCE AS IT DRIFTS SLOWLY SOUTHEAST INTO THE LOWER APPALACHIANS
BY MONDAY MORNING. THE LOCATION OF THE RIDGE AXIS WILL REMAIN WEST
OF THE FORECAST AREA INTO SUNDAY AND EVEN THEN WILL NOT PASS THROUGH
THE REGION UNTIL SUNDAY NIGHT. WITH THE SURFACE HIGH ANCHORED TO THE
SOUTHEAST...THIS WILL LEAVE MUCH OF THE OHIO VALLEY WITHIN A
STAGNANT FLOW PATTERN WITH NOTHING SUBSTANTIAL TO KICK OUT THE LOWER
CLOUDS.
DRY AIR AND SUBSIDENCE WILL INCREASE SATURDAY AND SUNDAY...HELPING
TO MAINTAIN AND STRENGTHEN A LOW LEVEL INVERSION. WITH MOISTURE
TRAPPED BENEATH THE INVERSION AND POSITION OF THE SURFACE HIGH AND
UPPER RIDGE AXIS MENTIONED ABOVE...SEE REALLY NO CHANCE FOR STRATUS
TO BREAK OVER THE AREA EITHER DAY THIS WEEKEND. HAVE GONE WELL ABOVE
SUPERBLEND GUIDANCE WITH RESPECT TO CLOUD COVER AS A RESULT.
OVERNIGHT FOG IS LIKELY TO LINGER INTO SATURDAY MORNING WITH SOME
IMPROVEMENT AS SURFACE WINDS INCREASE SLIGHTLY. CONSIDERED
MENTIONING PATCHY DRIZZLE ON SATURDAY WITH SUBTLE ISENTROPIC LIFT
PRESENT THROUGH 900MB...BUT SHALLOW MOISTURE LAYER MAY BE ENOUGH TO
SUPPORT. WILL CONTINUE TO MONITOR BUT HAVE LEFT DRIZZLE OUT FOR
SATURDAY AT THIS TIME.
CONFIDENCE IN DRIZZLE AND FOG IS HIGHER BEGINNING SATURDAY NIGHT AND
CONTINUING SUNDAY AS WEAK ISENTROPIC LIFT INCREASES A BIT AND THE
SATURATED LAYER RISES TO NEAR 4000FT. ONCE THE RIDGE AXIS PASSES
SUNDAY EVENING AND THE HIGH SHIFTS EAST...A MORE PRONOUNCED
SOUTHWEST FLOW IN THE LOW LEVELS SHOULD ENABLE THE INVERSION TO
FINALLY WEAKEN SOMEWHAT AND BRING AN END TO THE DRIZZLE AND FOG.
SURFACE LOW WILL TRACK INTO THE MISSOURI VALLEY ON MONDAY IN TANDEM
WITH A SHARP UPPER LOW CUTTING INTO THE BACK SIDE OF THE RIDGE.
FORCING WILL INCREASE AS THE DAY PROGRESSES MONDAY WITH RAIN
BECOMING LIKELY BY MONDAY EVENING.
TEMPS...HAVE GENERALLY THROWN OUT MOS FOR TEMPS ALL WEEKEND AND
RELIED INSTEAD MORE ON THE COOLER RAW MODEL TEMPS. MOS APPEARS TOO
WARM ALL THREE DAYS AND PARTICULARLY ON SUNDAY AND MONDAY. THIS
RESULTED IN HIGH TEMPS GENERALLY 2-4 DEGREES BELOW THE COLDER MAVMOS
AND HAVE SOME CONCERNS MAY NOT HAVE GONE COOL ENOUGH FOR SATURDAY
AND SUNDAY. LOWS WILL RISE TO NEAR 40 DEGREES BY MONDAY MORNING.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 221 PM EST FRI DEC 12 2014
SOME DIFFERENCES IN MODELS IN HOW FAST RAIN RETURNS LATE IN THE
PERIOD. RELIED MORE ON THE ECMWF/HPC EXTENDED FORECAST
THERE...OTHERWISE MODELS CLOSE ENOUGH THAT THE SUPERBLEND
INITIALIZATION WAS ACCEPTED.
SURFACE AND UPPER LOWS TO OUR NORTH WILL BRING A GOOD CHANCE FOR
RAIN MONDAY NIGHT...WITH SOME LINGERING RAIN POSSIBLE ON TUESDAY.
HIGH PRESSURE WILL MOVE IN AND WILL PROVIDE DRY CONDITIONS ON
WEDNESDAY.
MODELS DIFFER ON THURSDAY WITH GFS BRINGING AN UPPER SYSTEM ALONG
WITH CHANCES FOR RAIN...WHILE ECMWF REMAINS DRY. PREFER THE
DRIER SOLUTION AS JUST DO NOT SEE ANYTHING STRONG ENOUGH TO GENERATE
PRECIPITATION...ESPECIALLY WITH HIGH PRESSURE TRYING TO BUILD IN AT
THE SURFACE.
ALSO REMOVED ANY SUPERBLEND POPS ON FRIDAY AS GFS IS ONLY MODEL
BRINGING RAIN INTO THE AREA AND IT IS USUALLY TOO FAST.
TEMPERATURES LOOK TO BE SEASONABLE.
&&
.AVIATION /DISCUSSION FOR THE 13/0300Z TAF UPDATE/...
ISSUED AT 917 PM EST FRI DEC 12 2014
UPDATE...
NO CHANGES...MVFR FOG AND CEILINGS ARE CONTINUING.
PREVIOUS DISCUSSION...
IFR/MVFR CONDITIONS WILL PREVAIL THROUGH THE NIGHT WITH PERSISTENT
LOW LEVEL CLOUD DECK AND FOG FORMATION AS MOISTURE REMAINS TRAPPED
IN THE LOWER LEVELS. IFR/MVFR FOG WILL LINGER THROUGH MID-MORNING
TOMORROW AND FINALLY DISSIPATE BY LATE MORNING. MVFR CONDITIONS
WILL BECOME THE PREVAILING FLIGHT CATEGORY AT THAT POINT THROUGH
THE REMAINDER OF THE TAF PERIOD. WINDS WILL BE WEST/SOUTHWESTERLY
AT 4 TO 8 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...50
AVIATION...TDUD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
630 PM EST FRI DEC 12 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 338 PM EST FRI DEC 12 2014
DESPITE HIGH PRESSURE OVER THE REGION...TRAPPED LOW LEVEL MOISTURE
WILL KEEP CLOUDY SKIES WITH OCCASIONAL FOG AND DRIZZLE THROUGH THE
WEEKEND. RAIN WILL DEVELOP MONDAY THROUGH TUESDAY AS LOW PRESSURE
TRACKS INTO THE GREAT LAKES. MAINLY DRY WEATHER WILL RETURN FOR MUCH
OF THE REST OF THE WEEK ALONG WITH SEASONABLY COOL TEMPERATURES.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 338 PM EST FRI DEC 12 2014
STRATUS DECK AS OF 20Z HAS ENCOMPASSED MOST OF THE FORECAST
AREA...WITH JUST FAR EASTERN COUNTIES STILL ENJOYING SUNSHINE.
CLEARING IS ALSO ATTEMPTING TO SNEAK INTO THE LOWER WABASH VALLEY.
TEMPS HAVE BEEN KEPT DOWN AS A RESULT OF THE CLOUD DECK AND PATCHY
FOG IN SPOTS. TEMPS LARGELY REMAINED IN THE LOWER/MID 30S.
PRIMARY CHALLENGE FOR TONIGHT FOCUSES ON FOG POTENTIAL AS STRATUS
DECK SETTLES IN OVER CENTRAL INDIANA. CONTINUE TO LEAN ON THE RAP
WHICH HAS CAPTURED THE CLOUD DECK EXPANSION WELL SO FAR TODAY. LOWER
RH VALUES IN THE 925-950MB RANGE OVER SOUTHERN ILLINOIS THIS
AFTERNOON IN VICINITY OF THE CURRENT AREA OF CLEARING. SHOULD SEE
THIS CLEARING POKE INTO FAR SOUTHWEST COUNTIES OVER THE NEXT FEW
HOURS. LOW LEVEL FLOW PROGGED TO GRADUALLY VEER TO THE W/NW THIS
EVENING...AND THIS WILL FORCE THE CLEARING BACK TO THE SOUTHWEST
WITH THE STRATUS REESTABLISHING OVER THE LOWER WABASH VALLEY.
MODEL SOUNDINGS INDICATE THE SHALLOW INVERSION WILL STRENGTHEN
OVERNIGHT BELOW 2500FT...SUPPORTING THICK MVFR/IFR STRATUS AND FOG
DEVELOPMENT WITH A RELATIVELY STAGNANT AIRMASS OVERHEAD. LIGHT WINDS
SHOULD KEEP VISIBILITIES FROM GETTING WAY DOWN...BUT DO EXPECT AREAS
OF 2-3SM DEVELOPING OVERNIGHT WITH POCKETS OF LOWER VISIBILITIES.
TEMPS...HAVE TRENDED WITH THE RAP HOURLIES OVERNIGHT. LOWS ARE
EXPECTED DURING THE EVENING WITH STEADY OR SLOWLY RISING TEMPS
PRIMARILY IN THE 30S THEREAFTER. SUBFREEZING TEMPS MAY LINGER OVER
NORTHERN COUNTIES FOR MUCH OF THE NIGHT BEFORE WARMING TO OR ABOVE
32F. SHOULD ANY THICKER FOG DEVELOP...FREEZING FOG COULD BE A
POTENTIAL CONCERN. WILL NEED TO MONITOR TEMP/FOG TRENDS THROUGH THE
NIGHT.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 338 PM EST FRI DEC 12 2014
FORECAST CHALLENGES FOCUS ON FOG...DRIZZLE AND TEMPS AS CLOUDS
RETURN FOR AN EXTENDED STAY ACROSS THE HOOSIER STATE. RAIN ARRIVES
MONDAY WITH THE APPROACH OF LOW PRESSURE. THE SUN HAS AGAIN TAKEN AN
EXTENDED HOLIDAY.
HIGHLY AMPLIFIED FLOW ALOFT ACROSS THE LOWER 48 WITH A DEEP UPPER
LOW OVER NEW ENGLAND AND AN ANOMALOUSLY STRONG RIDGE OVER THE
CENTRAL PLAINS. THE UPPER LOW WILL SLOWLY DRIFT EAST INTO THE
ATLANTIC OVER THE WEEKEND WITH THE RIDGE GRADUALLY DEAMPLIFYING OVER
THE OHIO VALLEY. SURFACE HIGH PRESSURE WILL REMAIN A DOMINANT
INFLUENCE AS IT DRIFTS SLOWLY SOUTHEAST INTO THE LOWER APPALACHIANS
BY MONDAY MORNING. THE LOCATION OF THE RIDGE AXIS WILL REMAIN WEST
OF THE FORECAST AREA INTO SUNDAY AND EVEN THEN WILL NOT PASS THROUGH
THE REGION UNTIL SUNDAY NIGHT. WITH THE SURFACE HIGH ANCHORED TO THE
SOUTHEAST...THIS WILL LEAVE MUCH OF THE OHIO VALLEY WITHIN A
STAGNANT FLOW PATTERN WITH NOTHING SUBSTANTIAL TO KICK OUT THE LOWER
CLOUDS.
DRY AIR AND SUBSIDENCE WILL INCREASE SATURDAY AND SUNDAY...HELPING
TO MAINTAIN AND STRENGTHEN A LOW LEVEL INVERSION. WITH MOISTURE
TRAPPED BENEATH THE INVERSION AND POSITION OF THE SURFACE HIGH AND
UPPER RIDGE AXIS MENTIONED ABOVE...SEE REALLY NO CHANCE FOR STRATUS
TO BREAK OVER THE AREA EITHER DAY THIS WEEKEND. HAVE GONE WELL ABOVE
SUPERBLEND GUIDANCE WITH RESPECT TO CLOUD COVER AS A RESULT.
OVERNIGHT FOG IS LIKELY TO LINGER INTO SATURDAY MORNING WITH SOME
IMPROVEMENT AS SURFACE WINDS INCREASE SLIGHTLY. CONSIDERED
MENTIONING PATCHY DRIZZLE ON SATURDAY WITH SUBTLE ISENTROPIC LIFT
PRESENT THROUGH 900MB...BUT SHALLOW MOISTURE LAYER MAY BE ENOUGH TO
SUPPORT. WILL CONTINUE TO MONITOR BUT HAVE LEFT DRIZZLE OUT FOR
SATURDAY AT THIS TIME.
CONFIDENCE IN DRIZZLE AND FOG IS HIGHER BEGINNING SATURDAY NIGHT AND
CONTINUING SUNDAY AS WEAK ISENTROPIC LIFT INCREASES A BIT AND THE
SATURATED LAYER RISES TO NEAR 4000FT. ONCE THE RIDGE AXIS PASSES
SUNDAY EVENING AND THE HIGH SHIFTS EAST...A MORE PRONOUNCED
SOUTHWEST FLOW IN THE LOW LEVELS SHOULD ENABLE THE INVERSION TO
FINALLY WEAKEN SOMEWHAT AND BRING AN END TO THE DRIZZLE AND FOG.
SURFACE LOW WILL TRACK INTO THE MISSOURI VALLEY ON MONDAY IN TANDEM
WITH A SHARP UPPER LOW CUTTING INTO THE BACK SIDE OF THE RIDGE.
FORCING WILL INCREASE AS THE DAY PROGRESSES MONDAY WITH RAIN
BECOMING LIKELY BY MONDAY EVENING.
TEMPS...HAVE GENERALLY THROWN OUT MOS FOR TEMPS ALL WEEKEND AND
RELIED INSTEAD MORE ON THE COOLER RAW MODEL TEMPS. MOS APPEARS TOO
WARM ALL THREE DAYS AND PARTICULARLY ON SUNDAY AND MONDAY. THIS
RESULTED IN HIGH TEMPS GENERALLY 2-4 DEGREES BELOW THE COLDER MAVMOS
AND HAVE SOME CONCERNS MAY NOT HAVE GONE COOL ENOUGH FOR SATURDAY
AND SUNDAY. LOWS WILL RISE TO NEAR 40 DEGREES BY MONDAY MORNING.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 221 PM EST FRI DEC 12 2014
SOME DIFFERENCES IN MODELS IN HOW FAST RAIN RETURNS LATE IN THE
PERIOD. RELIED MORE ON THE ECMWF/HPC EXTENDED FORECAST
THERE...OTHERWISE MODELS CLOSE ENOUGH THAT THE SUPERBLEND
INITIALIZATION WAS ACCEPTED.
SURFACE AND UPPER LOWS TO OUR NORTH WILL BRING A GOOD CHANCE FOR
RAIN MONDAY NIGHT...WITH SOME LINGERING RAIN POSSIBLE ON TUESDAY.
HIGH PRESSURE WILL MOVE IN AND WILL PROVIDE DRY CONDITIONS ON
WEDNESDAY.
MODELS DIFFER ON THURSDAY WITH GFS BRINGING AN UPPER SYSTEM ALONG
WITH CHANCES FOR RAIN...WHILE ECMWF REMAINS DRY. PREFER THE
DRIER SOLUTION AS JUST DO NOT SEE ANYTHING STRONG ENOUGH TO GENERATE
PRECIPITATION...ESPECIALLY WITH HIGH PRESSURE TRYING TO BUILD IN AT
THE SURFACE.
ALSO REMOVED ANY SUPERBLEND POPS ON FRIDAY AS GFS IS ONLY MODEL
BRINGING RAIN INTO THE AREA AND IT IS USUALLY TOO FAST.
TEMPERATURES LOOK TO BE SEASONABLE.
&&
.AVIATION /DISCUSSION FOR THE 13/0000Z TAF ISSUANCE/...
ISSUED AT 622 PM EST FRI DEC 12 2014
IFR/MVFR CONDITIONS WILL PREVAIL THROUGH THE NIGHT WITH PERSISTENT
LOW LEVEL CLOUD DECK AND FOG FORMATION AS MOISTURE REMAINS TRAPPED
IN THE LOWER LEVELS. IFR/MVFR FOG WILL LINGER THROUGH MID-MORNING
TOMORROW AND FINALLY DISSIPATE BY LATE MORNING. MVFR CONDITIONS
WILL BECOME THE PREVAILING FLIGHT CATEGORY AT THAT POINT THROUGH
THE REMAINDER OF THE TAF PERIOD. WINDS WILL BE WEST/SOUTHWESTERLY
AT 4 TO 8 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...50
AVIATION...TDUD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
338 PM EST FRI DEC 12 2014
.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED
BELOW.
&&
.SYNOPSIS...
ISSUED AT 338 PM EST FRI DEC 12 2014
DESPITE HIGH PRESSURE OVER THE REGION...TRAPPED LOW LEVEL MOISTURE
WILL KEEP CLOUDY SKIES WITH OCCASIONAL FOG AND DRIZZLE THROUGH THE
WEEKEND. RAIN WILL DEVELOP MONDAY THROUGH TUESDAY AS LOW PRESSURE
TRACKS INTO THE GREAT LAKES. MAINLY DRY WEATHER WILL RETURN FOR MUCH
OF THE REST OF THE WEEK ALONG WITH SEASONABLY COOL TEMPERATURES.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 338 PM EST FRI DEC 12 2014
STRATUS DECK AS OF 20Z HAS ENCOMPASSED MOST OF THE FORECAST
AREA...WITH JUST FAR EASTERN COUNTIES STILL ENJOYING SUNSHINE.
CLEARING IS ALSO ATTEMPTING TO SNEAK INTO THE LOWER WABASH VALLEY.
TEMPS HAVE BEEN KEPT DOWN AS A RESULT OF THE CLOUD DECK AND PATCHY
FOG IN SPOTS. TEMPS LARGELY REMAINED IN THE LOWER/MID 30S.
PRIMARY CHALLENGE FOR TONIGHT FOCUSES ON FOG POTENTIAL AS STRATUS
DECK SETTLES IN OVER CENTRAL INDIANA. CONTINUE TO LEAN ON THE RAP
WHICH HAS CAPTURED THE CLOUD DECK EXPANSION WELL SO FAR TODAY. LOWER
RH VALUES IN THE 925-950MB RANGE OVER SOUTHERN ILLINOIS THIS
AFTERNOON IN VICINITY OF THE CURRENT AREA OF CLEARING. SHOULD SEE
THIS CLEARING POKE INTO FAR SOUTHWEST COUNTIES OVER THE NEXT FEW
HOURS. LOW LEVEL FLOW PROGGED TO GRADUALLY VEER TO THE W/NW THIS
EVENING...AND THIS WILL FORCE THE CLEARING BACK TO THE SOUTHWEST
WITH THE STRATUS REESTABLISHING OVER THE LOWER WABASH VALLEY.
MODEL SOUNDINGS INDICATE THE SHALLOW INVERSION WILL STRENGTHEN
OVERNIGHT BELOW 2500FT...SUPPORTING THICK MVFR/IFR STRATUS AND FOG
DEVELOPMENT WITH A RELATIVELY STAGNANT AIRMASS OVERHEAD. LIGHT WINDS
SHOULD KEEP VISIBILITIES FROM GETTING WAY DOWN...BUT DO EXPECT AREAS
OF 2-3SM DEVELOPING OVERNIGHT WITH POCKETS OF LOWER VISIBILITIES.
TEMPS...HAVE TRENDED WITH THE RAP HOURLIES OVERNIGHT. LOWS ARE
EXPECTED DURING THE EVENING WITH STEADY OR SLOWLY RISING TEMPS
PRIMARILY IN THE 30S THEREAFTER. SUBFREEZING TEMPS MAY LINGER OVER
NORTHERN COUNTIES FOR MUCH OF THE NIGHT BEFORE WARMING TO OR ABOVE
32F. SHOULD ANY THICKER FOG DEVELOP...FREEZING FOG COULD BE A
POTENTIAL CONCERN. WILL NEED TO MONITOR TEMP/FOG TRENDS THROUGH THE
NIGHT.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 338 PM EST FRI DEC 12 2014
FORECAST CHALLENGES FOCUS ON FOG...DRIZZLE AND TEMPS AS CLOUDS
RETURN FOR AN EXTENDED STAY ACROSS THE HOOSIER STATE. RAIN ARRIVES
MONDAY WITH THE APPROACH OF LOW PRESSURE. THE SUN HAS AGAIN TAKEN AN
EXTENDED HOLIDAY.
HIGHLY AMPLIFIED FLOW ALOFT ACROSS THE LOWER 48 WITH A DEEP UPPER
LOW OVER NEW ENGLAND AND AN ANOMALOUSLY STRONG RIDGE OVER THE
CENTRAL PLAINS. THE UPPER LOW WILL SLOWLY DRIFT EAST INTO THE
ATLANTIC OVER THE WEEKEND WITH THE RIDGE GRADUALLY DEAMPLIFYING OVER
THE OHIO VALLEY. SURFACE HIGH PRESSURE WILL REMAIN A DOMINANT
INFLUENCE AS IT DRIFTS SLOWLY SOUTHEAST INTO THE LOWER APPALACHIANS
BY MONDAY MORNING. THE LOCATION OF THE RIDGE AXIS WILL REMAIN WEST
OF THE FORECAST AREA INTO SUNDAY AND EVEN THEN WILL NOT PASS THROUGH
THE REGION UNTIL SUNDAY NIGHT. WITH THE SURFACE HIGH ANCHORED TO THE
SOUTHEAST...THIS WILL LEAVE MUCH OF THE OHIO VALLEY WITHIN A
STAGNANT FLOW PATTERN WITH NOTHING SUBSTANTIAL TO KICK OUT THE LOWER
CLOUDS.
DRY AIR AND SUBSIDENCE WILL INCREASE SATURDAY AND SUNDAY...HELPING
TO MAINTAIN AND STRENGTHEN A LOW LEVEL INVERSION. WITH MOISTURE
TRAPPED BENEATH THE INVERSION AND POSITION OF THE SURFACE HIGH AND
UPPER RIDGE AXIS MENTIONED ABOVE...SEE REALLY NO CHANCE FOR STRATUS
TO BREAK OVER THE AREA EITHER DAY THIS WEEKEND. HAVE GONE WELL ABOVE
SUPERBLEND GUIDANCE WITH RESPECT TO CLOUD COVER AS A RESULT.
OVERNIGHT FOG IS LIKELY TO LINGER INTO SATURDAY MORNING WITH SOME
IMPROVEMENT AS SURFACE WINDS INCREASE SLIGHTLY. CONSIDERED
MENTIONING PATCHY DRIZZLE ON SATURDAY WITH SUBTLE ISENTROPIC LIFT
PRESENT THROUGH 900MB...BUT SHALLOW MOISTURE LAYER MAY BE ENOUGH TO
SUPPORT. WILL CONTINUE TO MONITOR BUT HAVE LEFT DRIZZLE OUT FOR
SATURDAY AT THIS TIME.
CONFIDENCE IN DRIZZLE AND FOG IS HIGHER BEGINNING SATURDAY NIGHT AND
CONTINUING SUNDAY AS WEAK ISENTROPIC LIFT INCREASES A BIT AND THE
SATURATED LAYER RISES TO NEAR 4000FT. ONCE THE RIDGE AXIS PASSES
SUNDAY EVENING AND THE HIGH SHIFTS EAST...A MORE PRONOUNCED
SOUTHWEST FLOW IN THE LOW LEVELS SHOULD ENABLE THE INVERSION TO
FINALLY WEAKEN SOMEWHAT AND BRING AN END TO THE DRIZZLE AND FOG.
SURFACE LOW WILL TRACK INTO THE MISSOURI VALLEY ON MONDAY IN TANDEM
WITH A SHARP UPPER LOW CUTTING INTO THE BACK SIDE OF THE RIDGE.
FORCING WILL INCREASE AS THE DAY PROGRESSES MONDAY WITH RAIN
BECOMING LIKELY BY MONDAY EVENING.
TEMPS...HAVE GENERALLY THROWN OUT MOS FOR TEMPS ALL WEEKEND AND
RELIED INSTEAD MORE ON THE COOLER RAW MODEL TEMPS. MOS APPEARS TOO
WARM ALL THREE DAYS AND PARTICULARLY ON SUNDAY AND MONDAY. THIS
RESULTED IN HIGH TEMPS GENERALLY 2-4 DEGREES BELOW THE COLDER MAVMOS
AND HAVE SOME CONCERNS MAY NOT HAVE GONE COOL ENOUGH FOR SATURDAY
AND SUNDAY. LOWS WILL RISE TO NEAR 40 DEGREES BY MONDAY MORNING.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 221 PM EST FRI DEC 12 2014
SOME DIFFERENCES IN MODELS IN HOW FAST RAIN RETURNS LATE IN THE
PERIOD. RELIED MORE ON THE ECMWF/HPC EXTENDED FORECAST
THERE...OTHERWISE MODELS CLOSE ENOUGH THAT THE SUPERBLEND
INITIALIZATION WAS ACCEPTED.
SURFACE AND UPPER LOWS TO OUR NORTH WILL BRING A GOOD CHANCE FOR
RAIN MONDAY NIGHT...WITH SOME LINGERING RAIN POSSIBLE ON TUESDAY.
HIGH PRESSURE WILL MOVE IN AND WILL PROVIDE DRY CONDITIONS ON
WEDNESDAY.
MODELS DIFFER ON THURSDAY WITH GFS BRINGING AN UPPER SYSTEM ALONG
WITH CHANCES FOR RAIN...WHILE ECMWF REMAINS DRY. PREFER THE
DRIER SOLUTION AS JUST DO NOT SEE ANYTHING STRONG ENOUGH TO GENERATE
PRECIPITATION...ESPECIALLY WITH HIGH PRESSURE TRYING TO BUILD IN AT
THE SURFACE.
ALSO REMOVED ANY SUPERBLEND POPS ON FRIDAY AS GFS IS ONLY MODEL
BRINGING RAIN INTO THE AREA AND IT IS USUALLY TOO FAST.
TEMPERATURES LOOK TO BE SEASONABLE.
&&
.AVIATION /DISCUSSION FOR THE 121800Z TAF ISSUANCE/...
ISSUED AT 333 PM EST FRI DEC 12 2014
MINOR TWEAKS MADE TO KIND TAF TO BETTER MATCH CURRENT CONDITIONS.
NO OTHER CHANGES ARE NEEDED AT THIS TIME.
PREVIOUS AVIATION DISCUSSION FOLLOWS...
MVFR /WITH SOME IFR AT TIMES/ THROUGH THE TAF PERIOD.
LOW CLOUDS HAVE OVERSPREAD THE TAF SITES AT THIS TIME. CONDITIONS
ARE GENERALLY IFR. SATELLITE SHOWS SOME BREAKS IN THE LOWER CLOUDS
UPSTREAM WHICH HAS ALLOWED CEILINGS TO RISE INTO MVFR CATEGORY
/ALBEIT WITH SOME STUBBORN POCKETS OF IFR/.
EXPECT CEILINGS TO RISE SOME THIS AFTERNOON WITH SOME MIXING SO WENT
WITH BECOMING MVFR EARLY IN THE TAF PERIOD. VISIBILITY SHOULD
IMPROVE TO MVFR OR VFR AS WELL WITH THE MIXING.
MOISTURE WILL LINGER INTO SATURDAY SO KEPT MVFR CEILINGS THROUGH THE
PERIOD...AND ADDED SOME MVFR VISIBILITIES AS WELL. IFR COULD
REDEVELOP THOUGH OVERNIGHT...BUT AM NOT READY TO ADD IT AT THIS
TIME.
WINDS WILL GENERALLY REMAIN LESS THAN 10KT THROUGH THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...50
AVIATION...50/JH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
333 PM EST FRI DEC 12 2014
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 300 AM EST FRI DEC 12 2014
HIGH PRESSURE WILL RESULT IN DRY WEATHER WITH ABOVE NORMAL
TEMPERATURES THIS WEEKEND. THEN...THERE WILL BE RAIN CHANCES EARLY
NEXT WEEK AS A PACIFIC SYSTEM MOVES SLOWLY NORTHEAST ACROSS THE
MIDDLE MISSISSIPPI VALLEY AND GREAT LAKES. A FEW SNOW FLAKES COULD
MIX IN TUESDAY NIGHT ON THE BACK END OF THE SYSTEM. TEMPERATURES
WILL THEN DROP TO NORMAL OR SLIGHTLY BELOW MIDWEEK IN THE WAKE OF
THIS SYSTEM. AFTER A BRIEF DRY PERIOD...THERE WILL BE ANOTHER CHANCE
OF RAIN ON THURSDAY ASSOCIATED WITH ANOTHER PACIFIC SYSTEM.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1032 AM EST FRI DEC 12 2014
THICK STRATUS DECK MAKING STEADY EASTWARD PROGRESS ACROSS THE
FORECAST AREA AS OF MID MORNING. TEMPS WERE MAINLY IN THE 20S AS
OF 1430Z.
FOR THOSE WHO HAVE ENJOYED THE SUNSHINE THURSDAY AND SO FAR THIS
MORNING...MIGHT WANT TO GET OUT AND SOAK IT UP OVER THE NEXT FEW
HOURS BEFORE ITS GONE. OVERALL MODEL GUIDANCE HAS BEEN POOR IN
HANDLING THE EXPANSION OF THE CLOUD DECK SO FAR THIS MORNING.
CURRENT RAP SEEMS TO BE DOING FAR AND AWAY THE BEST JOB ON THE
STRATUS AND HAVE UTILIZED IT FOR THE REST OF THE DAY. MODEL
SOUNDINGS INDICATE A SHALLOW YET STOUT INVERSION DEVELOPING AS THE
CLOUDS ARRIVE WITH RAP 950MB RH PROGS IN EXCESS OF 90% OVER THE
NEXT FEW HOURS. HAVE INCREASED CLOUD COVERAGE SUBSTANTIALLY AS A
RESULT WITH MAINLY CLOUDY SKIES MOST EVERYWHERE BY AFTERNOON.
ONLY OTHER SIGNIFICANT CHANGE WAS TO HIGH TEMPS TODAY. WITH THE
ARRIVAL OF THE LOW STRATUS...SEE LITTLE CHANCE FOR TEMPS TO WARM
AS MUCH AS PREVIOUSLY THOUGHT. TOOK A BLEND OF THE RAP RAW SURFACE
TEMPS AND THE LAMP DATA WHICH RESULTED IN DROPPING HIGHS NEARLY 5
DEGREES ACROSS THE BOARD. AND THAT MAY NOT BE ENOUGH. ONE OTHER
NOTE...HAVE SEEN POCKETS OF FREEZING DRIZZLE BEING REPORTED OVER
NORTHERN ILLINOIS THIS MORNING. BELIEVE THERE IS TOO MUCH DRY AIR
ALOFT OVER CENTRAL INDIANA TO SUPPORT ANY FREEZING DRIZZLE/DRIZZLE
LATER TODAY BUT WILL NEED TO MONITOR.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM.../FRIDAY THROUGH MONDAY/
ISSUED AT 300 AM EST THU DEC 11 2014
SHORT TERM FOCUS IS ON SKY COVER AND TEMPERATURES.
MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE EAST
ACROSS THE APPALACHIANS BY SUNDAY AS A SHARP UPPER RIDGE MOVES OVER
THE GREAT LAKES AND OHIO VALLEY. MODELS ALSO ALL SUGGEST THAT
NEGATIVELY TILTED PACIFIC UPPER TROUGH LIFTING NORTHEAST OVER THE
SOUTHERN PLAINS SUNDAY NIGHT WILL BE TOO FAR AWAY TO WARRANT POPS
LATE IN THE EXTENDED.
925 MILLIBAR THICKNESSES AND SOUNDINGS SUGGEST PLENTY OF CLOUD COVER
THROUGH THE SHORT TERM WHICH SHOULD KEEP TEMPERATURES DOWN DURING
THE DAY TO A POINT. MOS DOES NOT SEEM TO INCLUDE ENOUGH CLOUD COVER.
HOWEVER...1000-850 MILLIBAR THICKNESSES TO 1340 METERS ON SUNDAY
SUGGEST AFTERNOON TEMPERATURES COULD REACH THE 50S DESPITE THE CLOUD
OVER...ESPECIALLY WEST OF INTERSTATE 65. MEANWHILE...AFTERNOON HIGHS
IN THE MID AND UPPER 40S LOOK GOOD FOR SATURDAY. NORMAL HIGH
TEMPERATURES THIS TIME OF YEAR ARE FROM THE UPPER 30S TO THE MID
40S. THIS WOULD TRANSLATE TO TEMPERATURES NEAR 5 DEGREES ABOVE
NORMAL ON SATURDAY AND AROUND 10 DEGREES ABOVE NORMAL BY SUNDAY.
MOS LOOKS A BIT TOO WARM ON SUNDAY. WITH MORE CLOUDS THEN MOS
SUGGESTS...WILL GO AT OR ABOVE MOS FOR OVERNIGHT LOWS WITH LOWS IN
THE 30S SATURDAY NIGHT AND 40S SUNDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 221 PM EST FRI DEC 12 2014
SOME DIFFERENCES IN MODELS IN HOW FAST RAIN RETURNS LATE IN THE
PERIOD. RELIED MORE ON THE ECMWF/HPC EXTENDED FORECAST
THERE...OTHERWISE MODELS CLOSE ENOUGH THAT THE SUPERBLEND
INITIALIZATION WAS ACCEPTED.
SURFACE AND UPPER LOWS TO OUR NORTH WILL BRING A GOOD CHANCE FOR
RAIN MONDAY NIGHT...WITH SOME LINGERING RAIN POSSIBLE ON TUESDAY.
HIGH PRESSURE WILL MOVE IN AND WILL PROVIDE DRY CONDITIONS ON
WEDNESDAY.
MODELS DIFFER ON THURSDAY WITH GFS BRINGING AN UPPER SYSTEM ALONG
WITH CHANCES FOR RAIN...WHILE ECMWF REMAINS DRY. PREFER THE
DRIER SOLUTION AS JUST DO NOT SEE ANYTHING STRONG ENOUGH TO GENERATE
PRECIPITATION...ESPECIALLY WITH HIGH PRESSURE TRYING TO BUILD IN AT
THE SURFACE.
ALSO REMOVED ANY SUPERBLEND POPS ON FRIDAY AS GFS IS ONLY MODEL
BRINGING RAIN INTO THE AREA AND IT IS USUALLY TOO FAST.
TEMPERATURES LOOK TO BE SEASONABLE.
&&
.AVIATION /DISCUSSION FOR THE 121800Z TAF ISSUANCE/...
ISSUED AT 333 PM EST FRI DEC 12 2014
MINOR TWEAKS MADE TO KIND TAF TO BETTER MATCH CURRENT CONDITIONS.
NO OTHER CHANGES ARE NEEDED AT THIS TIME.
PREVIOUS AVIATION DISCUSSION FOLLOWS...
MVFR /WITH SOME IFR AT TIMES/ THROUGH THE TAF PERIOD.
LOW CLOUDS HAVE OVERSPREAD THE TAF SITES AT THIS TIME. CONDITIONS
ARE GENERALLY IFR. SATELLITE SHOWS SOME BREAKS IN THE LOWER CLOUDS
UPSTREAM WHICH HAS ALLOWED CEILINGS TO RISE INTO MVFR CATEGORY
/ALBEIT WITH SOME STUBBORN POCKETS OF IFR/.
EXPECT CEILINGS TO RISE SOME THIS AFTERNOON WITH SOME MIXING SO WENT
WITH BECOMING MVFR EARLY IN THE TAF PERIOD. VISIBILITY SHOULD
IMPROVE TO MVFR OR VFR AS WELL WITH THE MIXING.
MOISTURE WILL LINGER INTO SATURDAY SO KEPT MVFR CEILINGS THROUGH THE
PERIOD...AND ADDED SOME MVFR VISIBILITIES AS WELL. IFR COULD
REDEVELOP THOUGH OVERNIGHT...BUT AM NOT READY TO ADD IT AT THIS
TIME.
WINDS WILL GENERALLY REMAIN LESS THAN 10KT THROUGH THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM...50
AVIATION...50/JH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
221 PM EST FRI DEC 12 2014
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 300 AM EST FRI DEC 12 2014
HIGH PRESSURE WILL RESULT IN DRY WEATHER WITH ABOVE NORMAL
TEMPERATURES THIS WEEKEND. THEN...THERE WILL BE RAIN CHANCES EARLY
NEXT WEEK AS A PACIFIC SYSTEM MOVES SLOWLY NORTHEAST ACROSS THE
MIDDLE MISSISSIPPI VALLEY AND GREAT LAKES. A FEW SNOW FLAKES COULD
MIX IN TUESDAY NIGHT ON THE BACK END OF THE SYSTEM. TEMPERATURES
WILL THEN DROP TO NORMAL OR SLIGHTLY BELOW MIDWEEK IN THE WAKE OF
THIS SYSTEM. AFTER A BRIEF DRY PERIOD...THERE WILL BE ANOTHER CHANCE
OF RAIN ON THURSDAY ASSOCIATED WITH ANOTHER PACIFIC SYSTEM.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1032 AM EST FRI DEC 12 2014
THICK STRATUS DECK MAKING STEADY EASTWARD PROGRESS ACROSS THE
FORECAST AREA AS OF MID MORNING. TEMPS WERE MAINLY IN THE 20S AS
OF 1430Z.
FOR THOSE WHO HAVE ENJOYED THE SUNSHINE THURSDAY AND SO FAR THIS
MORNING...MIGHT WANT TO GET OUT AND SOAK IT UP OVER THE NEXT FEW
HOURS BEFORE ITS GONE. OVERALL MODEL GUIDANCE HAS BEEN POOR IN
HANDLING THE EXPANSION OF THE CLOUD DECK SO FAR THIS MORNING.
CURRENT RAP SEEMS TO BE DOING FAR AND AWAY THE BEST JOB ON THE
STRATUS AND HAVE UTILIZED IT FOR THE REST OF THE DAY. MODEL
SOUNDINGS INDICATE A SHALLOW YET STOUT INVERSION DEVELOPING AS THE
CLOUDS ARRIVE WITH RAP 950MB RH PROGS IN EXCESS OF 90% OVER THE
NEXT FEW HOURS. HAVE INCREASED CLOUD COVERAGE SUBSTANTIALLY AS A
RESULT WITH MAINLY CLOUDY SKIES MOST EVERYWHERE BY AFTERNOON.
ONLY OTHER SIGNIFICANT CHANGE WAS TO HIGH TEMPS TODAY. WITH THE
ARRIVAL OF THE LOW STRATUS...SEE LITTLE CHANCE FOR TEMPS TO WARM
AS MUCH AS PREVIOUSLY THOUGHT. TOOK A BLEND OF THE RAP RAW SURFACE
TEMPS AND THE LAMP DATA WHICH RESULTED IN DROPPING HIGHS NEARLY 5
DEGREES ACROSS THE BOARD. AND THAT MAY NOT BE ENOUGH. ONE OTHER
NOTE...HAVE SEEN POCKETS OF FREEZING DRIZZLE BEING REPORTED OVER
NORTHERN ILLINOIS THIS MORNING. BELIEVE THERE IS TOO MUCH DRY AIR
ALOFT OVER CENTRAL INDIANA TO SUPPORT ANY FREEZING DRIZZLE/DRIZZLE
LATER TODAY BUT WILL NEED TO MONITOR.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM.../FRIDAY THROUGH MONDAY/
ISSUED AT 300 AM EST THU DEC 11 2014
SHORT TERM FOCUS IS ON SKY COVER AND TEMPERATURES.
MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE EAST
ACROSS THE APPALACHIANS BY SUNDAY AS A SHARP UPPER RIDGE MOVES OVER
THE GREAT LAKES AND OHIO VALLEY. MODELS ALSO ALL SUGGEST THAT
NEGATIVELY TILTED PACIFIC UPPER TROUGH LIFTING NORTHEAST OVER THE
SOUTHERN PLAINS SUNDAY NIGHT WILL BE TOO FAR AWAY TO WARRANT POPS
LATE IN THE EXTENDED.
925 MILLIBAR THICKNESSES AND SOUNDINGS SUGGEST PLENTY OF CLOUD COVER
THROUGH THE SHORT TERM WHICH SHOULD KEEP TEMPERATURES DOWN DURING
THE DAY TO A POINT. MOS DOES NOT SEEM TO INCLUDE ENOUGH CLOUD COVER.
HOWEVER...1000-850 MILLIBAR THICKNESSES TO 1340 METERS ON SUNDAY
SUGGEST AFTERNOON TEMPERATURES COULD REACH THE 50S DESPITE THE CLOUD
OVER...ESPECIALLY WEST OF INTERSTATE 65. MEANWHILE...AFTERNOON HIGHS
IN THE MID AND UPPER 40S LOOK GOOD FOR SATURDAY. NORMAL HIGH
TEMPERATURES THIS TIME OF YEAR ARE FROM THE UPPER 30S TO THE MID
40S. THIS WOULD TRANSLATE TO TEMPERATURES NEAR 5 DEGREES ABOVE
NORMAL ON SATURDAY AND AROUND 10 DEGREES ABOVE NORMAL BY SUNDAY.
MOS LOOKS A BIT TOO WARM ON SUNDAY. WITH MORE CLOUDS THEN MOS
SUGGESTS...WILL GO AT OR ABOVE MOS FOR OVERNIGHT LOWS WITH LOWS IN
THE 30S SATURDAY NIGHT AND 40S SUNDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 221 PM EST FRI DEC 12 2014
SOME DIFFERENCES IN MODELS IN HOW FAST RAIN RETURNS LATE IN THE
PERIOD. RELIED MORE ON THE ECMWF/HPC EXTENDED FORECAST
THERE...OTHERWISE MODELS CLOSE ENOUGH THAT THE SUPERBLEND
INITIALIZATION WAS ACCEPTED.
SURFACE AND UPPER LOWS TO OUR NORTH WILL BRING A GOOD CHANCE FOR
RAIN MONDAY NIGHT...WITH SOME LINGERING RAIN POSSIBLE ON TUESDAY.
HIGH PRESSURE WILL MOVE IN AND WILL PROVIDE DRY CONDITIONS ON
WEDNESDAY.
MODELS DIFFER ON THURSDAY WITH GFS BRINGING AN UPPER SYSTEM ALONG
WITH CHANCES FOR RAIN...WHILE ECMWF REMAINS DRY. PREFER THE
DRIER SOLUTION AS JUST DO NOT SEE ANYTHING STRONG ENOUGH TO GENERATE
PRECIPITATION...ESPECIALLY WITH HIGH PRESSURE TRYING TO BUILD IN AT
THE SURFACE.
ALSO REMOVED ANY SUPERBLEND POPS ON FRIDAY AS GFS IS ONLY MODEL
BRINGING RAIN INTO THE AREA AND IT IS USUALLY TOO FAST.
TEMPERATURES LOOK TO BE SEASONABLE.
&&
.AVIATION /DISCUSSION FOR THE 121800Z TAF ISSUANCE/...
ISSUED AT 1125 AM EST FRI DEC 12 2014
MVFR /WITH SOME IFR AT TIMES/ THROUGH THE TAF PERIOD.
LOW CLOUDS HAVE OVERSPREAD THE TAF SITES AT THIS TIME. CONDITIONS
ARE GENERALLY IFR. SATELLITE SHOWS SOME BREAKS IN THE LOWER CLOUDS
UPSTREAM WHICH HAS ALLOWED CEILINGS TO RISE INTO MVFR CATEGORY
/ALBEIT WITH SOME STUBBORN POCKETS OF IFR/.
EXPECT CEILINGS TO RISE SOME THIS AFTERNOON WITH SOME MIXING SO WENT
WITH BECOMING MVFR EARLY IN THE TAF PERIOD. VISIBILITY SHOULD
IMPROVE TO MVFR OR VFR AS WELL WITH THE MIXING.
MOISTURE WILL LINGER INTO SATURDAY SO KEPT MVFR CEILINGS THROUGH THE
PERIOD...AND ADDED SOME MVFR VISIBILITIES AS WELL. IFR COULD
REDEVELOP THOUGH OVERNIGHT...BUT AM NOT READY TO ADD IT AT THIS
TIME.
WINDS WILL GENERALLY REMAIN LESS THAN 10KT THROUGH THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM...50
AVIATION...50
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1125 AM EST FRI DEC 12 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 300 AM EST FRI DEC 12 2014
HIGH PRESSURE WILL RESULT IN DRY WEATHER WITH ABOVE NORMAL
TEMPERATURES THIS WEEKEND. THEN...THERE WILL BE RAIN CHANCES EARLY
NEXT WEEK AS A PACIFIC SYSTEM MOVES SLOWLY NORTHEAST ACROSS THE
MIDDLE MISSISSIPPI VALLEY AND GREAT LAKES. A FEW SNOW FLAKES COULD
MIX IN TUESDAY NIGHT ON THE BACK END OF THE SYSTEM. TEMPERATURES
WILL THEN DROP TO NORMAL OR SLIGHTLY BELOW MIDWEEK IN THE WAKE OF
THIS SYSTEM. AFTER A BRIEF DRY PERIOD...THERE WILL BE ANOTHER CHANCE
OF RAIN ON THURSDAY ASSOCIATED WITH ANOTHER PACIFIC SYSTEM.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1032 AM EST FRI DEC 12 2014
THICK STRATUS DECK MAKING STEADY EASTWARD PROGRESS ACROSS THE
FORECAST AREA AS OF MID MORNING. TEMPS WERE MAINLY IN THE 20S AS
OF 1430Z.
FOR THOSE WHO HAVE ENJOYED THE SUNSHINE THURSDAY AND SO FAR THIS
MORNING...MIGHT WANT TO GET OUT AND SOAK IT UP OVER THE NEXT FEW
HOURS BEFORE ITS GONE. OVERALL MODEL GUIDANCE HAS BEEN POOR IN
HANDLING THE EXPANSION OF THE CLOUD DECK SO FAR THIS MORNING.
CURRENT RAP SEEMS TO BE DOING FAR AND AWAY THE BEST JOB ON THE
STRATUS AND HAVE UTILIZED IT FOR THE REST OF THE DAY. MODEL
SOUNDINGS INDICATE A SHALLOW YET STOUT INVERSION DEVELOPING AS THE
CLOUDS ARRIVE WITH RAP 950MB RH PROGS IN EXCESS OF 90% OVER THE
NEXT FEW HOURS. HAVE INCREASED CLOUD COVERAGE SUBSTANTIALLY AS A
RESULT WITH MAINLY CLOUDY SKIES MOST EVERYWHERE BY AFTERNOON.
ONLY OTHER SIGNIFICANT CHANGE WAS TO HIGH TEMPS TODAY. WITH THE
ARRIVAL OF THE LOW STRATUS...SEE LITTLE CHANCE FOR TEMPS TO WARM
AS MUCH AS PREVIOUSLY THOUGHT. TOOK A BLEND OF THE RAP RAW SURFACE
TEMPS AND THE LAMP DATA WHICH RESULTED IN DROPPING HIGHS NEARLY 5
DEGREES ACROSS THE BOARD. AND THAT MAY NOT BE ENOUGH. ONE OTHER
NOTE...HAVE SEEN POCKETS OF FREEZING DRIZZLE BEING REPORTED OVER
NORTHERN ILLINOIS THIS MORNING. BELIEVE THERE IS TOO MUCH DRY AIR
ALOFT OVER CENTRAL INDIANA TO SUPPORT ANY FREEZING DRIZZLE/DRIZZLE
LATER TODAY BUT WILL NEED TO MONITOR.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM.../FRIDAY THROUGH MONDAY/
ISSUED AT 300 AM EST THU DEC 11 2014
SHORT TERM FOCUS IS ON SKY COVER AND TEMPERATURES.
MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE EAST
ACROSS THE APPALACHIANS BY SUNDAY AS A SHARP UPPER RIDGE MOVES OVER
THE GREAT LAKES AND OHIO VALLEY. MODELS ALSO ALL SUGGEST THAT
NEGATIVELY TILTED PACIFIC UPPER TROUGH LIFTING NORTHEAST OVER THE
SOUTHERN PLAINS SUNDAY NIGHT WILL BE TOO FAR AWAY TO WARRANT POPS
LATE IN THE EXTENDED.
925 MILLIBAR THICKNESSES AND SOUNDINGS SUGGEST PLENTY OF CLOUD COVER
THROUGH THE SHORT TERM WHICH SHOULD KEEP TEMPERATURES DOWN DURING
THE DAY TO A POINT. MOS DOES NOT SEEM TO INCLUDE ENOUGH CLOUD COVER.
HOWEVER...1000-850 MILLIBAR THICKNESSES TO 1340 METERS ON SUNDAY
SUGGEST AFTERNOON TEMPERATURES COULD REACH THE 50S DESPITE THE CLOUD
OVER...ESPECIALLY WEST OF INTERSTATE 65. MEANWHILE...AFTERNOON HIGHS
IN THE MID AND UPPER 40S LOOK GOOD FOR SATURDAY. NORMAL HIGH
TEMPERATURES THIS TIME OF YEAR ARE FROM THE UPPER 30S TO THE MID
40S. THIS WOULD TRANSLATE TO TEMPERATURES NEAR 5 DEGREES ABOVE
NORMAL ON SATURDAY AND AROUND 10 DEGREES ABOVE NORMAL BY SUNDAY.
MOS LOOKS A BIT TOO WARM ON SUNDAY. WITH MORE CLOUDS THEN MOS
SUGGESTS...WILL GO AT OR ABOVE MOS FOR OVERNIGHT LOWS WITH LOWS IN
THE 30S SATURDAY NIGHT AND 40S SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH NEXT THURSDAY/...
ISSUED AT 300 AM EST FRI DEC 12 2014
ENSEMBLES ARE IN FAIRLY GOOD AGREEMENT EARLY IN THE EXTENDED WITH
THE EJECTION OF AN UPPER TROUGH THROUGH THE PLAINS AND ACROSS THE
LOCAL AREA EARLY NEXT WEEK. WILL CONTINUE WITH POPS FROM MONDAY
THROUGH TUESDAY NIGHT TO COVER THIS SYSTEM. ENSEMBLES SUGGEST LITTLE
THREAT FOR SNOW WITH THIS SYSTEM...EXCEPT FOR MAYBE SOME LIGHT SNOW
TUESDAY NIGHT AS COLDER AIR WRAPS IN BEHIND THE SYSTEM.
LOWER CONFIDENCE IN THE FORECAST LATER NEXT WEEK AS ENSEMBLES DIFFER
ON THE EVOLVING PATTERN. A SLIM MAJORITY OF THE ENSEMBLES INDICATE
ANOTHER DEEP TROUGH WILL DEVELOP OVER THE EAST COAST BY THE MIDDLE
OF NEXT WEEK...WITH RIDGING OVER THE MIDWEST...WHILE OTHERS SUGGEST
A MORE PROGRESSIVE LESS AMPLIFIED PATTERN. IF THE MORE PROGRESSIVE
SOLUTIONS END UP BEING CORRECT...MILDER CONDITIONS ALONG WITH A
PRECIPITATION THREAT MAY ARRIVE AS EARLY AS NEXT THURSDAY...WHILE
THE MORE AMPLIFIED SOLUTIONS SUGGEST A COLDER PATTER WITH THE
PRECIPITATION THREAT NOT ARRIVING UNTIL AFTER THIS PERIOD. FOR
NOW...WILL ADD SOME SMALL POPS FOR LIGHT RAIN FOR NEXT THURSDAY TO
COVER THE MORE PROGRESSIVE SOLUTIONS.
&&
.AVIATION /DISCUSSION FOR THE 121800Z TAF ISSUANCE/...
ISSUED AT 1125 AM EST FRI DEC 12 2014
MVFR /WITH SOME IFR AT TIMES/ THROUGH THE TAF PERIOD.
LOW CLOUDS HAVE OVERSPREAD THE TAF SITES AT THIS TIME. CONDITIONS
ARE GENERALLY IFR. SATELLITE SHOWS SOME BREAKS IN THE LOWER CLOUDS
UPSTREAM WHICH HAS ALLOWED CEILINGS TO RISE INTO MVFR CATEGORY
/ALBEIT WITH SOME STUBBORN POCKETS OF IFR/.
EXPECT CEILINGS TO RISE SOME THIS AFTERNOON WITH SOME MIXING SO WENT
WITH BECOMING MVFR EARLY IN THE TAF PERIOD. VISIBILITY SHOULD
IMPROVE TO MVFR OR VFR AS WELL WITH THE MIXING.
MOISTURE WILL LINGER INTO SATURDAY SO KEPT MVFR CEILINGS THROUGH THE
PERIOD...AND ADDED SOME MVFR VISIBILITIES AS WELL. IFR COULD
REDEVELOP THOUGH OVERNIGHT...BUT AM NOT READY TO ADD IT AT THIS
TIME.
WINDS WILL GENERALLY REMAIN LESS THAN 10KT THROUGH THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM...JAS
AVIATION...50
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1116 AM EST FRI DEC 12 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 300 AM EST FRI DEC 12 2014
HIGH PRESSURE WILL RESULT IN DRY WEATHER WITH ABOVE NORMAL
TEMPERATURES THIS WEEKEND. THEN...THERE WILL BE RAIN CHANCES EARLY
NEXT WEEK AS A PACIFIC SYSTEM MOVES SLOWLY NORTHEAST ACROSS THE
MIDDLE MISSISSIPPI VALLEY AND GREAT LAKES. A FEW SNOW FLAKES COULD
MIX IN TUESDAY NIGHT ON THE BACK END OF THE SYSTEM. TEMPERATURES
WILL THEN DROP TO NORMAL OR SLIGHTLY BELOW MIDWEEK IN THE WAKE OF
THIS SYSTEM. AFTER A BRIEF DRY PERIOD...THERE WILL BE ANOTHER CHANCE
OF RAIN ON THURSDAY ASSOCIATED WITH ANOTHER PACIFIC SYSTEM.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1032 AM EST FRI DEC 12 2014
THICK STRATUS DECK MAKING STEADY EASTWARD PROGRESS ACROSS THE
FORECAST AREA AS OF MID MORNING. TEMPS WERE MAINLY IN THE 20S AS
OF 1430Z.
FOR THOSE WHO HAVE ENJOYED THE SUNSHINE THURSDAY AND SO FAR THIS
MORNING...MIGHT WANT TO GET OUT AND SOAK IT UP OVER THE NEXT FEW
HOURS BEFORE ITS GONE. OVERALL MODEL GUIDANCE HAS BEEN POOR IN
HANDLING THE EXPANSION OF THE CLOUD DECK SO FAR THIS MORNING.
CURRENT RAP SEEMS TO BE DOING FAR AND AWAY THE BEST JOB ON THE
STRATUS AND HAVE UTILIZED IT FOR THE REST OF THE DAY. MODEL
SOUNDINGS INDICATE A SHALLOW YET STOUT INVERSION DEVELOPING AS THE
CLOUDS ARRIVE WITH RAP 950MB RH PROGS IN EXCESS OF 90% OVER THE
NEXT FEW HOURS. HAVE INCREASED CLOUD COVERAGE SUBSTANTIALLY AS A
RESULT WITH MAINLY CLOUDY SKIES MOST EVERYWHERE BY AFTERNOON.
ONLY OTHER SIGNIFICANT CHANGE WAS TO HIGH TEMPS TODAY. WITH THE
ARRIVAL OF THE LOW STRATUS...SEE LITTLE CHANCE FOR TEMPS TO WARM
AS MUCH AS PREVIOUSLY THOUGHT. TOOK A BLEND OF THE RAP RAW SURFACE
TEMPS AND THE LAMP DATA WHICH RESULTED IN DROPPING HIGHS NEARLY 5
DEGREES ACROSS THE BOARD. AND THAT MAY NOT BE ENOUGH. ONE OTHER
NOTE...HAVE SEEN POCKETS OF FREEZING DRIZZLE BEING REPORTED OVER
NORTHERN ILLINOIS THIS MORNING. BELIEVE THERE IS TOO MUCH DRY AIR
ALOFT OVER CENTRAL INDIANA TO SUPPORT ANY FREEZING DRIZZLE/DRIZZLE
LATER TODAY BUT WILL NEED TO MONITOR.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM.../FRIDAY THROUGH MONDAY/
ISSUED AT 300 AM EST THU DEC 11 2014
SHORT TERM FOCUS IS ON SKY COVER AND TEMPERATURES.
MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE EAST
ACROSS THE APPALACHIANS BY SUNDAY AS A SHARP UPPER RIDGE MOVES OVER
THE GREAT LAKES AND OHIO VALLEY. MODELS ALSO ALL SUGGEST THAT
NEGATIVELY TILTED PACIFIC UPPER TROUGH LIFTING NORTHEAST OVER THE
SOUTHERN PLAINS SUNDAY NIGHT WILL BE TOO FAR AWAY TO WARRANT POPS
LATE IN THE EXTENDED.
925 MILLIBAR THICKNESSES AND SOUNDINGS SUGGEST PLENTY OF CLOUD COVER
THROUGH THE SHORT TERM WHICH SHOULD KEEP TEMPERATURES DOWN DURING
THE DAY TO A POINT. MOS DOES NOT SEEM TO INCLUDE ENOUGH CLOUD COVER.
HOWEVER...1000-850 MILLIBAR THICKNESSES TO 1340 METERS ON SUNDAY
SUGGEST AFTERNOON TEMPERATURES COULD REACH THE 50S DESPITE THE CLOUD
OVER...ESPECIALLY WEST OF INTERSTATE 65. MEANWHILE...AFTERNOON HIGHS
IN THE MID AND UPPER 40S LOOK GOOD FOR SATURDAY. NORMAL HIGH
TEMPERATURES THIS TIME OF YEAR ARE FROM THE UPPER 30S TO THE MID
40S. THIS WOULD TRANSLATE TO TEMPERATURES NEAR 5 DEGREES ABOVE
NORMAL ON SATURDAY AND AROUND 10 DEGREES ABOVE NORMAL BY SUNDAY.
MOS LOOKS A BIT TOO WARM ON SUNDAY. WITH MORE CLOUDS THEN MOS
SUGGESTS...WILL GO AT OR ABOVE MOS FOR OVERNIGHT LOWS WITH LOWS IN
THE 30S SATURDAY NIGHT AND 40S SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH NEXT THURSDAY/...
ISSUED AT 300 AM EST FRI DEC 12 2014
ENSEMBLES ARE IN FAIRLY GOOD AGREEMENT EARLY IN THE EXTENDED WITH
THE EJECTION OF AN UPPER TROUGH THROUGH THE PLAINS AND ACROSS THE
LOCAL AREA EARLY NEXT WEEK. WILL CONTINUE WITH POPS FROM MONDAY
THROUGH TUESDAY NIGHT TO COVER THIS SYSTEM. ENSEMBLES SUGGEST LITTLE
THREAT FOR SNOW WITH THIS SYSTEM...EXCEPT FOR MAYBE SOME LIGHT SNOW
TUESDAY NIGHT AS COLDER AIR WRAPS IN BEHIND THE SYSTEM.
LOWER CONFIDENCE IN THE FORECAST LATER NEXT WEEK AS ENSEMBLES DIFFER
ON THE EVOLVING PATTERN. A SLIM MAJORITY OF THE ENSEMBLES INDICATE
ANOTHER DEEP TROUGH WILL DEVELOP OVER THE EAST COAST BY THE MIDDLE
OF NEXT WEEK...WITH RIDGING OVER THE MIDWEST...WHILE OTHERS SUGGEST
A MORE PROGRESSIVE LESS AMPLIFIED PATTERN. IF THE MORE PROGRESSIVE
SOLUTIONS END UP BEING CORRECT...MILDER CONDITIONS ALONG WITH A
PRECIPITATION THREAT MAY ARRIVE AS EARLY AS NEXT THURSDAY...WHILE
THE MORE AMPLIFIED SOLUTIONS SUGGEST A COLDER PATTER WITH THE
PRECIPITATION THREAT NOT ARRIVING UNTIL AFTER THIS PERIOD. FOR
NOW...WILL ADD SOME SMALL POPS FOR LIGHT RAIN FOR NEXT THURSDAY TO
COVER THE MORE PROGRESSIVE SOLUTIONS.
&&
.AVIATION /DISCUSSION FOR THE 121500Z TAF UPDATE/...
ISSUED AT 937 AM EST FRI DEC 12 2014
IFR CLOUD DECK CONTINUES TO MOVE STEADILY EAST INTO CENTRAL INDIANA
AT THE MOMENT. IF CURRENT TRENDS CONTINUE...THIS DECK SHOULD REACH
KIND AROUND 1530Z. UPDATED TAF TO REFLECT THIS. PLENTY OF
UNCERTAINTY ON HOW LONG IFR WILL LAST...SO LEFT IT IN FOR A FEW
HOURS BEFORE LIFTING TO MVFR.
PREVIOUS DISCUSSION FOLLOWS...
WIDESPREAD MVFR VISIBILITY RESTRICTIONS IN LIGHT FOG EXPECTED TO
LINGER INTO THE LATE MORNING HOURS...AS MIXING SHOULD REMAIN LIMITED
UNDER A STRONG LOW LEVEL INVERSION INDICATED ON LAST EVENING/S UPPER
AIR. POTENTIAL FOR SOME PATCHY IFR RESTRICTIONS FOR AN HOUR OR TWO
AFTER SUNRISE.
OTHERWISE...THE LEADING EDGE OF AN EXTENSIVE MVFR DECK AROUND 025
HAS BEEN SLOWLY PUSHING EAST ACROSS ILLINOIS. THESE CEILINGS SHOULD
SPREAD ACROSS THE TAF SITES FROM WEST TO EAST TOWARDS THE MIDDAY
HOURS AND ON INTO THE AFTERNOON AS THE LOW LEVEL FLOW REMAINS
WESTERLY.
LIGHT SURFACE WINDS EARLY THIS MORNING EXPECTED TO BECOME 270-290
DEGREES AT 6-9 KTS BY LATE MORNING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM...JAS
AVIATION...JAS/50
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1032 AM EST FRI DEC 12 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 300 AM EST FRI DEC 12 2014
HIGH PRESSURE WILL RESULT IN DRY WEATHER WITH ABOVE NORMAL
TEMPERATURES THIS WEEKEND. THEN...THERE WILL BE RAIN CHANCES EARLY
NEXT WEEK AS A PACIFIC SYSTEM MOVES SLOWLY NORTHEAST ACROSS THE
MIDDLE MISSISSIPPI VALLEY AND GREAT LAKES. A FEW SNOW FLAKES COULD
MIX IN TUESDAY NIGHT ON THE BACK END OF THE SYSTEM. TEMPERATURES
WILL THEN DROP TO NORMAL OR SLIGHTLY BELOW MIDWEEK IN THE WAKE OF
THIS SYSTEM. AFTER A BRIEF DRY PERIOD...THERE WILL BE ANOTHER CHANCE
OF RAIN ON THURSDAY ASSOCIATED WITH ANOTHER PACIFIC SYSTEM.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1032 AM EST FRI DEC 12 2014
THICK STRATUS DECK MAKING STEADY EASTWARD PROGRESS ACROSS THE
FORECAST AREA AS OF MID MORNING. TEMPS WERE MAINLY IN THE 20S AS
OF 1430Z.
FOR THOSE WHO HAVE ENJOYED THE SUNSHINE THURSDAY AND SO FAR THIS
MORNING...MIGHT WANT TO GET OUT AND SOAK IT UP OVER THE NEXT FEW
HOURS BEFORE ITS GONE. OVERALL MODEL GUIDANCE HAS BEEN POOR IN
HANDLING THE EXPANSION OF THE CLOUD DECK SO FAR THIS MORNING.
CURRENT RAP SEEMS TO BE DOING FAR AND AWAY THE BEST JOB ON THE
STRATUS AND HAVE UTILIZED IT FOR THE REST OF THE DAY. MODEL
SOUNDINGS INDICATE A SHALLOW YET STOUT INVERSION DEVELOPING AS THE
CLOUDS ARRIVE WITH RAP 950MB RH PROGS IN EXCESS OF 90% OVER THE
NEXT FEW HOURS. HAVE INCREASED CLOUD COVERAGE SUBSTANTIALLY AS A
RESULT WITH MAINLY CLOUDY SKIES MOST EVERYWHERE BY AFTERNOON.
ONLY OTHER SIGNIFICANT CHANGE WAS TO HIGH TEMPS TODAY. WITH THE
ARRIVAL OF THE LOW STRATUS...SEE LITTLE CHANCE FOR TEMPS TO WARM
AS MUCH AS PREVIOUSLY THOUGHT. TOOK A BLEND OF THE RAP RAW SURFACE
TEMPS AND THE LAMP DATA WHICH RESULTED IN DROPPING HIGHS NEARLY 5
DEGREES ACROSS THE BOARD. AND THAT MAY NOT BE ENOUGH. ONE OTHER
NOTE...HAVE SEEN POCKETS OF FREEZING DRIZZLE BEING REPORTED OVER
NORTHERN ILLINOIS AND AS CLOSE AS KANKAKEE THIS MORNING. BELIEVE
THERE IS TOO MUCH DRY AIR ALOFT OVER CENTRAL INDIANA TO SUPPORT
ANY FREEZING DRIZZLE/DRIZZLE LATER TODAY BUT WILL NEED TO MONITOR.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM.../FRIDAY THROUGH MONDAY/
ISSUED AT 300 AM EST THU DEC 11 2014
SHORT TERM FOCUS IS ON SKY COVER AND TEMPERATURES.
MODELS IN GOOD AGREEMENT THAT SURFACE HIGH PRESSURE WILL SETTLE EAST
ACROSS THE APPALACHIANS BY SUNDAY AS A SHARP UPPER RIDGE MOVES OVER
THE GREAT LAKES AND OHIO VALLEY. MODELS ALSO ALL SUGGEST THAT
NEGATIVELY TILTED PACIFIC UPPER TROUGH LIFTING NORTHEAST OVER THE
SOUTHERN PLAINS SUNDAY NIGHT WILL BE TOO FAR AWAY TO WARRANT POPS
LATE IN THE EXTENDED.
925 MILLIBAR THICKNESSES AND SOUNDINGS SUGGEST PLENTY OF CLOUD COVER
THROUGH THE SHORT TERM WHICH SHOULD KEEP TEMPERATURES DOWN DURING
THE DAY TO A POINT. MOS DOES NOT SEEM TO INCLUDE ENOUGH CLOUD COVER.
HOWEVER...1000-850 MILLIBAR THICKNESSES TO 1340 METERS ON SUNDAY
SUGGEST AFTERNOON TEMPERATURES COULD REACH THE 50S DESPITE THE CLOUD
OVER...ESPECIALLY WEST OF INTERSTATE 65. MEANWHILE...AFTERNOON HIGHS
IN THE MID AND UPPER 40S LOOK GOOD FOR SATURDAY. NORMAL HIGH
TEMPERATURES THIS TIME OF YEAR ARE FROM THE UPPER 30S TO THE MID
40S. THIS WOULD TRANSLATE TO TEMPERATURES NEAR 5 DEGREES ABOVE
NORMAL ON SATURDAY AND AROUND 10 DEGREES ABOVE NORMAL BY SUNDAY.
MOS LOOKS A BIT TOO WARM ON SUNDAY. WITH MORE CLOUDS THEN MOS
SUGGESTS...WILL GO AT OR ABOVE MOS FOR OVERNIGHT LOWS WITH LOWS IN
THE 30S SATURDAY NIGHT AND 40S SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH NEXT THURSDAY/...
ISSUED AT 300 AM EST FRI DEC 12 2014
ENSEMBLES ARE IN FAIRLY GOOD AGREEMENT EARLY IN THE EXTENDED WITH
THE EJECTION OF AN UPPER TROUGH THROUGH THE PLAINS AND ACROSS THE
LOCAL AREA EARLY NEXT WEEK. WILL CONTINUE WITH POPS FROM MONDAY
THROUGH TUESDAY NIGHT TO COVER THIS SYSTEM. ENSEMBLES SUGGEST LITTLE
THREAT FOR SNOW WITH THIS SYSTEM...EXCEPT FOR MAYBE SOME LIGHT SNOW
TUESDAY NIGHT AS COLDER AIR WRAPS IN BEHIND THE SYSTEM.
LOWER CONFIDENCE IN THE FORECAST LATER NEXT WEEK AS ENSEMBLES DIFFER
ON THE EVOLVING PATTERN. A SLIM MAJORITY OF THE ENSEMBLES INDICATE
ANOTHER DEEP TROUGH WILL DEVELOP OVER THE EAST COAST BY THE MIDDLE
OF NEXT WEEK...WITH RIDGING OVER THE MIDWEST...WHILE OTHERS SUGGEST
A MORE PROGRESSIVE LESS AMPLIFIED PATTERN. IF THE MORE PROGRESSIVE
SOLUTIONS END UP BEING CORRECT...MILDER CONDITIONS ALONG WITH A
PRECIPITATION THREAT MAY ARRIVE AS EARLY AS NEXT THURSDAY...WHILE
THE MORE AMPLIFIED SOLUTIONS SUGGEST A COLDER PATTER WITH THE
PRECIPITATION THREAT NOT ARRIVING UNTIL AFTER THIS PERIOD. FOR
NOW...WILL ADD SOME SMALL POPS FOR LIGHT RAIN FOR NEXT THURSDAY TO
COVER THE MORE PROGRESSIVE SOLUTIONS.
&&
.AVIATION /DISCUSSION FOR THE 121500Z TAF UPDATE/...
ISSUED AT 937 AM EST FRI DEC 12 2014
IFR CLOUD DECK CONTINUES TO MOVE STEADILY EAST INTO CENTRAL INDIANA
AT THE MOMENT. IF CURRENT TRENDS CONTINUE...THIS DECK SHOULD REACH
KIND AROUND 1530Z. UPDATED TAF TO REFLECT THIS. PLENTY OF
UNCERTAINTY ON HOW LONG IFR WILL LAST...SO LEFT IT IN FOR A FEW
HOURS BEFORE LIFTING TO MVFR.
PREVIOUS DISCUSSION FOLLOWS...
WIDESPREAD MVFR VISIBILITY RESTRICTIONS IN LIGHT FOG EXPECTED TO
LINGER INTO THE LATE MORNING HOURS...AS MIXING SHOULD REMAIN LIMITED
UNDER A STRONG LOW LEVEL INVERSION INDICATED ON LAST EVENING/S UPPER
AIR. POTENTIAL FOR SOME PATCHY IFR RESTRICTIONS FOR AN HOUR OR TWO
AFTER SUNRISE.
OTHERWISE...THE LEADING EDGE OF AN EXTENSIVE MVFR DECK AROUND 025
HAS BEEN SLOWLY PUSHING EAST ACROSS ILLINOIS. THESE CEILINGS SHOULD
SPREAD ACROSS THE TAF SITES FROM WEST TO EAST TOWARDS THE MIDDAY
HOURS AND ON INTO THE AFTERNOON AS THE LOW LEVEL FLOW REMAINS
WESTERLY.
LIGHT SURFACE WINDS EARLY THIS MORNING EXPECTED TO BECOME 270-290
DEGREES AT 6-9 KTS BY LATE MORNING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM...JAS
AVIATION...JAS/50
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1145 PM CST Sat Dec 13 2014
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Sunday)
Issued at 311 PM CST SAT DEC 13 2014
20Z water vapor imagery shows the upper level trough out west
continuing to progress east into the Rockies. Meanwhile the upper
ridge overhead is slowly weakening as height falls spread east. At
the surface, southerly low level flow persists between a ridge over
the southeast and troughing in the lee of the Rockies. Dewpoints in
the lower and middle 50s continue to move north into the central
plains.
Tonight there remains little large scale forcing, but the general
subsidence from the upper ridge should go away as it weakens.
Because of the lack of forcing, think chances for measurable precip
are relatively small given the moisture will be capped by the pesky
inversion and no real lift to force the moisture above the
inversion. However the continued advection of higher dewpoints north
along with some modest isentropic lift could lead to areas of
drizzle overnight. The RAP and NAM suggest isentropic lift will not
be any better organized than what is occurring this afternoon. So
thinking is the drizzle overnight will only amount to a trace. Temps
are expected to remain fairly steady with overcast skies and south
winds preventing any cooling. Min temps are forecast to be in the
lower to mid 50s
Sunday will see increasing large scale forcing in the form of
vorticity advection as the upper trough propagates east and a
negatively tilted shortwave lifts out from the southern Rockies. The
combination of the forcing with mid level cooling is expected to
create some modest convective instability (surface based CAPE around
500 J/KG). With this in mind, showers and thunderstorms should
develop over the southern high plains and spread into central KS by
the afternoon. Any strong to severe thunderstorms seem to be
dependent on the degree of surface heating and resultant
destabilization. At this point, heating is forecast to be modest due
to overcast skies. Although it is not out of the question there
could be a strong storm or two with some hail and wind. Highs Sunday
should be around 60 as southerly flow and warm air advection
persists.
.LONG TERM...(Sunday Night through Saturday)
Issued at 307 PM CST SAT DEC 13 2014
Initial band of precip with likely embedded convection should be
moving through Sunday evening. Kept PoPs above guidance but could
see a few places miss some precip in possible gaps in the band.
Minor instability still anticipated with this band, with somewhat
greater concern for severe weather arises in the evening to early
overnight hours with south low level winds persisting and wind
fields increasing as models are in good agreement with another area
of precip developing NE of the of the upper low. The NAM seems a bit
overdone with CAPE, mostly via cooling around 925mb on SW winds,
which seems unlikely. Still, with low tops the CAPE that is there is
a more impressive and minor wind and hail concerns remain. Monday
into Monday brings steady drying conditions but decreased PoPs
somewhat Monday night with NE KS well on the back side of this
system. Still have a hard time seeing much more than rain fall with
this event, with ice crystals aloft becoming hard to come by as the
lower levels cool. Falling temps on track for the daytime hours
Monday as NW winds increase.
Tuesday into at least Tuesday night still looking dry, but models
continue to struggle with upper troughing splitting NE into Canada
and SE into the southern tier states as well as how energy will
interact with an upper high pushing east across the southern
Canadian provinces. This puts much of the Northern and Central Plains
in weak flow and seasonable temperature fields, with any waves
passing near enough from the south to bring light precip
potential, with the later work week periods again looking the most
likely for this to occur. Low chance PoPs at best are in order
with somewhat cooler lower levels supporting less mixed precip
potential.
&&
.AVIATION...(For the 06Z TAFs through 06Z Sunday Night)
Issued at 1136 PM CST SAT DEC 13 2014
Previous thoughts were that IFR conditions were prevail through
mid day tomorrow. Although conditions have currently improved to
MVFR. Since the model guidance does not imply this happening have
added a tempo for this variance. Towards the end of the period a
strong system will bring rain and thunderstorms. Decided not to
focus on thunderstorm possibilities and timing at this point.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...65
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS TOPEKA KS
543 PM CST Sat Dec 13 2014
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Sunday)
Issued at 311 PM CST SAT DEC 13 2014
20Z water vapor imagery shows the upper level trough out west
continuing to progress east into the Rockies. Meanwhile the upper
ridge overhead is slowly weakening as height falls spread east. At
the surface, southerly low level flow persists between a ridge over
the southeast and troughing in the lee of the Rockies. Dewpoints in
the lower and middle 50s continue to move north into the central
plains.
Tonight there remains little large scale forcing, but the general
subsidence from the upper ridge should go away as it weakens.
Because of the lack of forcing, think chances for measurable precip
are relatively small given the moisture will be capped by the pesky
inversion and no real lift to force the moisture above the
inversion. However the continued advection of higher dewpoints north
along with some modest isentropic lift could lead to areas of
drizzle overnight. The RAP and NAM suggest isentropic lift will not
be any better organized than what is occurring this afternoon. So
thinking is the drizzle overnight will only amount to a trace. Temps
are expected to remain fairly steady with overcast skies and south
winds preventing any cooling. Min temps are forecast to be in the
lower to mid 50s
Sunday will see increasing large scale forcing in the form of
vorticity advection as the upper trough propagates east and a
negatively tilted shortwave lifts out from the southern Rockies. The
combination of the forcing with mid level cooling is expected to
create some modest convective instability (surface based CAPE around
500 J/KG). With this in mind, showers and thunderstorms should
develop over the southern high plains and spread into central KS by
the afternoon. Any strong to severe thunderstorms seem to be
dependent on the degree of surface heating and resultant
destabilization. At this point, heating is forecast to be modest due
to overcast skies. Although it is not out of the question there
could be a strong storm or two with some hail and wind. Highs Sunday
should be around 60 as southerly flow and warm air advection
persists.
.LONG TERM...(Sunday Night through Saturday)
Issued at 307 PM CST SAT DEC 13 2014
Initial band of precip with likely embedded convection should be
moving through Sunday evening. Kept PoPs above guidance but could
see a few places miss some precip in possible gaps in the band.
Minor instability still anticipated with this band, with somewhat
greater concern for severe weather arises in the evening to early
overnight hours with south low level winds persisting and wind
fields increasing as models are in good agreement with another area
of precip developing NE of the of the upper low. The NAM seems a bit
overdone with CAPE, mostly via cooling around 925mb on SW winds,
which seems unlikely. Still, with low tops the CAPE that is there is
a more impressive and minor wind and hail concerns remain. Monday
into Monday brings steady drying conditions but decreased PoPs
somewhat Monday night with NE KS well on the back side of this
system. Still have a hard time seeing much more than rain fall with
this event, with ice crystals aloft becoming hard to come by as the
lower levels cool. Falling temps on track for the daytime hours
Monday as NW winds increase.
Tuesday into at least Tuesday night still looking dry, but models
continue to struggle with upper troughing splitting NE into Canada
and SE into the southern tier states as well as how energy will
interact with an upper high pushing east across the southern
Canadian provinces. This puts much of the Northern and Central Plains
in weak flow and seasonable temperature fields, with any waves
passing near enough from the south to bring light precip
potential, with the later work week periods again looking the most
likely for this to occur. Low chance PoPs at best are in order
with somewhat cooler lower levels supporting less mixed precip
potential.
&&
.AVIATION...(For the 00Z TAFs through 00Z Sunday Evening)
Issued at 525 PM CST SAT DEC 13 2014
Challenges for the TAF period remain the CIG/VIS through the
first part and most of the last half of the period into Sunday
afternoon. Expect CIG/VIS conditions to continue to exhibit a
range within the IFR/LIFR categories. It is not out of the
question to dip into the VLIFR range overnight for periods of
time. Outside of that, late afternoon on Sunday could see the
potential for showers and mostly weak general thunderstorms to
move into the area associated with the upper level trough to the
West of the terminals. A very isolated thunderstorm with small
hail could be embedded, but any potential for that should be after
the TAF period ends.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...65
AVIATION...Drake
AREA FORECAST DISCUSSION
NWS TOPEKA KS
311 PM CST Sat Dec 13 2014
.SHORT TERM...(This Evening through Sunday)
Issued at 311 PM CST SAT DEC 13 2014
20Z water vapor imagery shows the upper level trough out west
continuing to progress east into the Rockies. Meanwhile the upper
ridge overhead is slowly weakening as height falls spread east. At
the surface, southerly low level flow persists between a ridge over
the southeast and troughing in the lee of the Rockies. Dewpoints in
the lower and middle 50s continue to move north into the central
plains.
Tonight there remains little large scale forcing, but the general
subsidence from the upper ridge should go away as it weakens.
Because of the lack of forcing, think chances for measurable precip
are relatively small given the moisture will be capped by the pesky
inversion and no real lift to force the moisture above the
inversion. However the continued advection of higher dewpoints north
along with some modest isentropic lift could lead to areas of
drizzle overnight. The RAP and NAM suggest isentropic lift will not
be any better organized than what is occurring this afternoon. So
thinking is the drizzle overnight will only amount to a trace. Temps
are expected to remain fairly steady with overcast skies and south
winds preventing any cooling. Min temps are forecast to be in the
lower to mid 50s
Sunday will see increasing large scale forcing in the form of
vorticity advection as the upper trough propagates east and a
negatively tilted shortwave lifts out from the southern Rockies. The
combination of the forcing with mid level cooling is expected to
create some modest convective instability (surface based CAPE around
500 J/KG). With this in mind, showers and thunderstorms should
develop over the southern high plains and spread into central KS by
the afternoon. Any strong to severe thunderstorms seem to be
dependent on the degree of surface heating and resultant
destabilization. At this point, heating is forecast to be modest due
to overcast skies. Although it is not out of the question there
could be a strong storm or two with some hail and wind. Highs Sunday
should be around 60 as southerly flow and warm air advection
persists.
.LONG TERM...(Sunday Night through Saturday)
Issued at 307 PM CST SAT DEC 13 2014
Initial band of precip with likely embedded convection should be
moving through Sunday evening. Kept PoPs above guidance but could
see a few places miss some precip in possible gaps in the band.
Minor instability still anticipated with this band, with somewhat
greater concern for severe weather arises in the evening to early
overnight hours with south low level winds persisting and wind
fields increasing as models are in good agreement with another area
of precip developing NE of the of the upper low. The NAM seems a bit
overdone with CAPE, mostly via cooling around 925mb on SW winds,
which seems unlikely. Still, with low tops the CAPE that is there is
a more impressive and minor wind and hail concerns remain. Monday
into Monday brings steady drying conditions but decreased PoPs
somewhat Monday night with NE KS well on the back side of this
system. Still have a hard time seeing much more than rain fall with
this event, with ice crystals aloft becoming hard to come by as the
lower levels cool. Falling temps on track for the daytime hours
Monday as NW winds increase.
Tuesday into at least Tuesday night still looking dry, but models
continue to struggle with upper troughing splitting NE into Canada
and SE into the southern tier states as well as how energy will
interact with an upper high pushing east across the southern
Canadian provinces. This puts much of the Northern and Central Plains
in weak flow and seasonable temperature fields, with any waves
passing near enough from the south to bring light precip
potential, with the later work week periods again looking the most
likely for this to occur. Low chance PoPs at best are in order
with somewhat cooler lower levels supporting less mixed precip
potential.
&&
.AVIATION...(For the 18Z TAFs through 18Z Sunday Afternoon)
Issued at 1117 AM CST SAT DEC 13 2014
Models continue to point towards at best IFR conditions through
the next 24 hours. Still anticipate a slight improvement at FOE
and MHK this afternoon. However by this evening, think LIFR CIGS
will return as low level moisture continues to advect into the
area with models showing weak isentropic upglide. Timing the
changes is most uncertain, and the forecast is a best
approximation based on the RAP and NAM forecast soundings.
&&
.CLIMATE...
Issued at 311 PM CST SAT DEC 13 2014
Some records for these warm mid-December temps are likely to fall,
particularly the highest minimum temps.
Record highest low temperatures for December 13...
Topeka......42, set in 2008.
Concordia...40, set in 1921.
Record highs for December 14...
Topeka......70, set in 1933.
Concordia...64, set in 2006.
Record highest low temperatures for December 14...
Topeka......46, set in 2011.
Concordia...41, set in 1891.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...65
AVIATION...Wolters
CLIMATE...65
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1134 AM CST SAT DEC 13 2014
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1131 AM CST SAT DEC 13 2014
AT 12Z SATURDAY A 500MB TROUGH WAS LOCATED OVER NEVADA WITH 80
METER 12 HOUR 500MB HEIGHT FALLS REPORTED OVER EASTERN ARIZONA AND
WESTERN COLORADO. A +70 KNOT UPPER LEVEL JET EXTENDING FORM THE
BASED OF THIS UPPER TROUGH, ACROSS THE FOUR CORNERS REGION INTO
SOUTHERN WYOMING. AN UPPER LEVEL RIDGE AXIS EXTEND FROM WEST TEXAS
INTO THE WESTERN GREAT LAKES REGION. OVER THE CENTRAL HIGH PLAINS
AN 850 MB TROUGH WAS LOCATED ALONG THE LEE OF THE ROCKIES EARLIER
THIS MORNING WITH 850MB TEMPERATURE RANGING FROM +4C AT NORTH
PLATTE TO +9C AT DODGE CITY TO +15C AT AMARILLO. 850MB DEW POINTS
OVER WESTERN KANSAS RANGE FROM 5C TO 8C. AT THE SURFACE A
STATIONARY FRONT EXTENDED FROM SOUTHEAST COLORADO INTO THE NORTH
CENTRAL TEXAS. NORTH OF THIS SURFACE BOUNDARY A SOUTHEASTERLY UP
SLOPE FLOW WAS PRESENT WITH DEW POINTS RANGING FROM THE MID 40S IN
WEST CENTRAL KANSAS TO AROUND 50 IN NORTHWEST OKLAHOMA. STATUS AND
FOG WAS REPORTED EARLIER THIS MORNING ACROSS ALL OF WESTERN KANSAS
AND THE DODGE CITY SOUNDINGS INDICATED THE THE DEPTH OF THE LOW
LEVEL MOISTURE WAS AROUND 2100 FEET AGL.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 251 AM CST SAT DEC 13 2014
OVERNIGHT WEATHER REMAINED VERY FOGGY WITH ONE-QUARTER MILE OR LESS
VISIBILITY BEING OBSERVED OVER A FAIRLY LARGE PORTION OF SOUTHWEST
KANSAS. SURFACE ANALYSIS OVERNIGHT SHOWED THE 50F ISODROSOTHERM JUST
SOUTH OF THE KANSAS BORDER WITH MUCH OF THE SOUTHWEST KANSAS REGION
SITTING AT A DEWPOINT OF 46 TO 48F. WE WILL CONTINUE THE DENSE FOG
ADVISORY THROUGH THE LATE MORNING HOURS. SOME FINE-TUNING OF THE
FOG ADVISORY WILL BE NEEDED AFTER SUNRISE AS THE DENSE FOG AREA
SHRINKS. IT APPEARS THE BEST AREA TO KEEP FOG IN PLACE THROUGH
MIDDAY WILL BE SOUTH OF THE ARKANSAS RIVER AND EAST OF HIGHWAY
83...WITH THE LATEST HOURLY HRRR MODEL SUGGESTING ONE-QUARTER MILE
VISIBILITY HOLDING STRONG IN THESE AREAS THROUGH NOON.
AS THE UPPER LEVEL TROUGH CONTINUES TO PUSH EAST TODAY, WE WILL SEE
LOW LEVEL FLOW START TO VEER SOMEWHAT ON THE HIGH PLAINS. THIS WILL
ALLOW DEEPER MIXING OVER THE HIGH PLAINS WITH BETTER MOMENTUM
TRANSFER OUT WEST...ALLOWING THE WESTERN EDGE OF THE LOW STRATUS TO
SHIFT EAST BY AFTERNOON. THE BEST FORECAST FOR THE EDGE OF THE LOW
STRATUS BY MID-AFTERNOON IS ROUGHLY A DIGHTON TO CIMARRON TO MEADE
LINE (GIVE OR TAKE 20 OR 30 MILES). THIS WILL OBVIOUSLY HAVE AN
IMPACT ON TEMPERATURES, BUT EVEN WITH THE STRATUS ERODING,
HIGH CIRROSTRATUS WILL BE INCREASING FROM THE WEST, SO THIS WOULD
CURB THE WARM UP A BIT. NEVERTHELESS, WARMEST TEMPERATURES WILL BE
OUT IN THE FAR SOUTHWEST TODAY WITH HIGHS IN THE MID 60S AT ELKHART
AND LIBERAL. AREAS THAT REMAIN IN THE STRATUS ALL DAY FARTHER EAST
AND NORTH...TEMPERATURES WILL NOT GET ABOVE THE MID 50S.
DENSE FOG WILL LIKELY REDEVELOP AS SURFACE FLOW BACKS A BIT AFTER
SUNSET. AGAIN, WIDESPREAD VISIBILITIES OF ONE-QUARTER MILE OR LESS
APPEAR LIKELY, ESPECIALLY AT THE EDGE OF THE DIURNAL STRATUS SHIELD.
DEEPER MOISTURE WILL BE ADVANCING NORTHWARD FROM THE TEXAS PANHANDLE
IN THE 09-12Z TIME FRAME, LEADING TO SHOWER AND ISOLATED
THUNDERSTORM DEVELOPMENT. THE 4KM NAM AND WRF-ARW SUGGEST THE FIRST
SHOWERS AND ISOLATED THUNDERSTORMS MOVING INTO THE ELKHART TO
LIBERAL AREAS SHORTLY BEFORE SUNRISE SUNDAY MORNING...AND BECOMING
MORE NUMEROUS IN NATURE LATER IN THE MORNING (DISCUSSED FURTHER IN
THE LONG TERM SECTION).
AS FAR AS TEMPERATURES GO TONIGHT, THE ABNORMALLY HIGH DEWPOINTS
AROUND 49 TO 51F WILL OBVIOUSLY KEEP TEMPERATURES UP, AND A LOOK AT
THE RECORD BOOK FOR DODGE CITY REVEALS THAT THE DECEMBER 13
CALENDAR DAY RECORD HIGH-MINIMUM TEMPERATURE OF 42 DEGREES WILL
FALL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 300 AM CST SAT DEC 13 2014
SUNDAY:
AN ACTIVE WEATHER DAY ON SUNDAY WITH A SYNOPTIC WAVE TRAVERSING THE
REGION AND A FAIRLY WRAPPED UP LOW LEVEL CYCLONE PASSING ACROSS THE
CENTRAL AND SOUTHERN PLAINS. FORECAST REFLECTIVITY FROM THE 4 KM NAM
AND WRF-ARW LOOKS QUITE CONVECTIVE ACROSS THE REGION. THERE WILL BE
INSTABILITY WITH THE 500-HPA MID LEVEL COLD POOL MOVING CLOSER TO THE
FORECAST AREA AND AS LOW LEVEL LAPSE RATES STEEPEN WITH THE DISTURBANCE.
STRONG STORMS CANNOT BE RULED OUT GIVEN THE SHALLOW SUPERCELL NATURE
ENVIRONMENT THAT IS EXPECTED. IN ADDITION, PRECIPITATION LOADING COULD
RESULT TO WINDS BEING DRAGGED DOWN. EVERYTHING IS ON THE LOW END OF
THE SEVERE SPECTRUM, BUT THIS SYSTEM IS IMPRESSIVE FOR DECEMBER STANDARDS.
WHAT IS MORE AMUSING IS THE NAM SHOWS ACTUAL MODERATE FORECAST STP VALUES
ACROSS THE SOUTHERN PLAINS. SOMETHING TO THINK ABOUT BUT PROBABLY IS
OVER FORECAST. THERE WILL BE SOME SNOW ON THE BACKSIDE OF THE CYCLONE
AS INTENSE COLD AIR ADVECTION ENSUES. OVERALL, THE SYNOPTIC WAVE IS
WARM WITH POSITIVE TEMPERATURE ANOMALIES. THINK THAT THE OVERALL SNOWFALL
POTENTIAL IS MORE ON THE MARGINAL SIDE AND AMOUNTS SHOULD BE BELOW ADVISORY
THRESHOLD. THE MORE PRESSING ISSUES IS THUNDERSTORM THREAT WITH THE
REGION SEEING A DECENT SHOT AT LIQUID PRECIPITATION AMOUNTS.
MONDAY:
A TIGHT PRESSURE GRADIENT BEHIND THE LOW/FRONT WILL RESULT IN BREEZY
WINDS ACROSS THE REGION MONDAY AND MUCH COOLER TEMPERATURES IN THE WAKE
OF THE FRONT. THE FORECAST IS DRY AS SUBSIDENCE CONTINUES IN THE WAKE
OF THE SYNOPTIC WAVE. HIGHS WILL BE IN THE 40S AND LOWS IN THE 20S HEADING
INTO TUESDAY MORNING.
AND THE REST:
THE NEXT CHANCE FOR PRECIPITATION COMES WEDNESDAY NIGHT INTO THURSDAY.
FORECAST UNCERTAINTY IS LARGE AT THIS POINT SO STUCK WITH THE SUPERBLEND
SOLUTION DURING THIS PERIOD AND FOR THE REST OF THE FORECAST PERIOD.
TEMPERATURES WILL BE FAIRLY CLOSE TO SEASONAL NORMS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1131 AM CST SAT DEC 13 2014
BUFR SOUNDINGS INDICATING MOISTURE WILL BE SLOW TO ERODE TODAY
ACROSS PORTIONS OF WESTERN KANSAS. BASED ON LATEST VISIBLE
SATELLITE LOOP AND 12Z NAM VFR CONDITIONS ARE EXPECTED BY 19Z AT
GCK. MVFR WILL BRIEFLY DEVELOP AT DDC BETWEEN 21Z AND 03Z.
CEILINGS AT HYS ARE EXPECTED TO STAY BELOW 1000 FT AGL THIS
AFTERNOON WITH EVEN SOME PATCHY DRIZZLE POSSIBLE. AFTER 00Z THE
IFR/LIFR FOG AND CEILINGS WILL RETURN TO ALL THREE TAF SITES.
SOUTHEASTERLY WINDS WILL VEER MORE TO THE SOUTH OVERNIGHT NIGHT
BUT STILL APPEAR TO FAVOR SOME DENSE FOG DEVELOPING OVER PORTIONS
OF WESTERN KANSAS BETWEEN 03Z AND 12Z SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 57 52 56 34 / 10 10 90 20
GCK 60 50 54 30 / 10 30 90 60
EHA 67 47 54 29 / 0 50 60 30
LBL 66 52 57 31 / 10 50 60 20
HYS 55 51 56 33 / 10 10 90 80
P28 59 56 58 38 / 10 10 90 40
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR KSZ044-045-064>066-
077>081-087>090.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...UMSCHEID
LONG TERM...SUGDEN
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1117 AM CST Sat Dec 13 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 343 AM CST SAT DEC 13 2014
Weather conditions through tonight will be warm and damp as low
level moisture continues to stream north into the region.
Early Saturday morning, a sharp trough axis extended across Idaho
and Nevada with energy digging into the southern side of the trough
over southern Nevada. This trough will begin to deepen today and
will become a strong closed low by Sunday morning as it crosses the
Rockies. In advance of the system, surface cyclogenesis will occur,
slowly at first, in the lee of the Rockies. This will increase the
southerly low level flow and moisture feed into the region. The
result will be continued periods of drizzle and fog, particularly
this morning and again tonight. The fog is once again not likely to
be particularly dense, but could see dense pockets of fog at times,
mainly tonight. Otherwise, despite widespread cloud cover,
temperatures will be well above normal. Highs in the upper 50s are
likely, with some potential for a few 60 degree readings if the sun
can break through low clouds in a few areas this afternoon.
Widespread sunshine is not likely but the moisture is shallow enough
that a few breaks are possible. Overnight temperatures will not move
much, likely holding in the 50s with continued warm advection and
clouds.
.LONG TERM...(Sunday through Friday)
Issued at 343 AM CST SAT DEC 13 2014
By Sunday, the mid-level trough that is currently situated over the
western U.S. will have progressed eastward over the Rockies with the
mid-level low centered over northern New Mexico. Models show this
low lifting northeastward toward the forecast area through the day
and passing overhead Sunday night into Monday as the associated
surface cold front tracks eastward over the forecast area. Model
soundings show a very shallow moisture layer Sunday morning so
expect some patchy drizzle and fog before the deeper saturation
advects into the area. Several models are showing some elevated
instability as well as some weak surface-based instability Sunday
afternoon into evening, so have kept the mention of isolated
thunder. The best chances for widespread precipitation look to be
during the late Sunday afternoon through Monday morning time frame in
which many locations should receive one-quarter to at least
three-quarters of an inch of rain. Despite the mostly cloudy skies,
the breezy southerly flow ahead of the advancing system will aid in
warm air advection on Sunday with highs reaching near the 60 degree
mark. Models continue to show the cold air lagging well behind this
system with low temperatures Sunday night expected to range from the
upper 40s east to mid/upper 30s west. Temperatures should be
steadily falling through the day on Monday as the cold air finally
advances into the area. While we start losing the deep saturation by
Monday afternoon and evening, there is a chance for some light
precipitation to linger across the area, which could be in the form
of a rain/snow mix as a result of these falling temperatures.
However, any wintry precipitation that develops should be very
short-lived as the system should finally exit the area Monday night.
Dry and cooler conditions are expected Tuesday into Wednesday as
surface high pressure builds in behind the exiting system. High
temperatures should only reach into the mid/upper 30s and possibly
low 40s with low temperatures plunging back into the 20s. During
this time models show another mid-level trough moving onshore to the
west and eventually advancing into the central U.S. by mid to late
week. There are still significant model discrepancies with the
timing and tracking of this system, with the GFS being much more
progressive in bringing the wave and associated precipitation into
the area Wednesday and Wednesday night while the ECMWF lifts
precipitation into the area Thursday through Friday. Have trended
more with the slower ECMWF solution, so have kept a dry forecast for
Wednesday and have increasing PoPs through the end of the week. This
next system should keep the cooler airmass in place over the region
with highs staying in the 30s and lows in the 20s. As a result,
there will be chances for a mix of rain and snow with this system so
we will need to closely monitor this system over the upcoming days
to better fine-tune this potential for wintry precipitation.
&&
.AVIATION...(For the 18Z TAFs through 18Z Sunday Afternoon)
Issued at 1117 AM CST SAT DEC 13 2014
Models continue to point towards at best IFR conditions through
the next 24 hours. Still anticipate a slight improvement at FOE
and MHK this afternoon. However by this evening, think LIFR CIGS
will return as low level moisture continues to advect into the
area with models showing weak isentropic upglide. Timing the
changes is most uncertain, and the forecast is a best
approximation based on the RAP and NAM forecast soundings.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Barjenbruch
LONG TERM...Hennecke
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
500 AM CST SAT DEC 13 2014
...UPDATE TO AVIATION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 251 AM CST SAT DEC 13 2014
OVERNIGHT WEATHER REMAINED VERY FOGGY WITH ONE-QUARTER MILE OR LESS
VISIBILITY BEING OBSERVED OVER A FAIRLY LARGE PORTION OF SOUTHWEST
KANSAS. SURFACE ANALYSIS OVERNIGHT SHOWED THE 50F ISODROSOTHERM JUST
SOUTH OF THE KANSAS BORDER WITH MUCH OF THE SOUTHWEST KANSAS REGION
SITTING AT A DEWPOINT OF 46 TO 48F. WE WILL CONTINUE THE DENSE FOG
ADVISORY THROUGH THE LATE MORNING HOURS. SOME FINE-TUNING OF THE
FOG ADVISORY WILL BE NEEDED AFTER SUNRISE AS THE DENSE FOG AREA
SHRINKS. IT APPEARS THE BEST AREA TO KEEP FOG IN PLACE THROUGH
MIDDAY WILL BE SOUTH OF THE ARKANSAS RIVER AND EAST OF HIGHWAY
83...WITH THE LATEST HOURLY HRRR MODEL SUGGESTING ONE-QUARTER MILE
VISIBILITY HOLDING STRONG IN THESE AREAS THROUGH NOON.
AS THE UPPER LEVEL TROUGH CONTINUES TO PUSH EAST TODAY, WE WILL SEE
LOW LEVEL FLOW START TO VEER SOMEWHAT ON THE HIGH PLAINS. THIS WILL
ALLOW DEEPER MIXING OVER THE HIGH PLAINS WITH BETTER MOMENTUM
TRANSFER OUT WEST...ALLOWING THE WESTERN EDGE OF THE LOW STRATUS TO
SHIFT EAST BY AFTERNOON. THE BEST FORECAST FOR THE EDGE OF THE LOW
STRATUS BY MID-AFTERNOON IS ROUGHLY A DIGHTON TO CIMARRON TO MEADE
LINE (GIVE OR TAKE 20 OR 30 MILES). THIS WILL OBVIOUSLY HAVE AN
IMPACT ON TEMPERATURES, BUT EVEN WITH THE STRATUS ERODING,
HIGH CIRROSTRATUS WILL BE INCREASING FROM THE WEST, SO THIS WOULD
CURB THE WARM UP A BIT. NEVERTHELESS, WARMEST TEMPERATURES WILL BE
OUT IN THE FAR SOUTHWEST TODAY WITH HIGHS IN THE MID 60S AT ELKHART
AND LIBERAL. AREAS THAT REMAIN IN THE STRATUS ALL DAY FARTHER EAST
AND NORTH...TEMPERATURES WILL NOT GET ABOVE THE MID 50S.
DENSE FOG WILL LIKELY REDEVELOP AS SURFACE FLOW BACKS A BIT AFTER
SUNSET. AGAIN, WIDESPREAD VISIBILITIES OF ONE-QUARTER MILE OR LESS
APPEAR LIKELY, ESPECIALLY AT THE EDGE OF THE DIURNAL STRATUS SHIELD.
DEEPER MOISTURE WILL BE ADVANCING NORTHWARD FROM THE TEXAS PANHANDLE
IN THE 09-12Z TIME FRAME, LEADING TO SHOWER AND ISOLATED
THUNDERSTORM DEVELOPMENT. THE 4KM NAM AND WRF-ARW SUGGEST THE FIRST
SHOWERS AND ISOLATED THUNDERSTORMS MOVING INTO THE ELKHART TO
LIBERAL AREAS SHORTLY BEFORE SUNRISE SUNDAY MORNING...AND BECOMING
MORE NUMEROUS IN NATURE LATER IN THE MORNING (DISCUSSED FURTHER IN
THE LONG TERM SECTION).
AS FAR AS TEMPERATURES GO TONIGHT, THE ABNORMALLY HIGH DEWPOINTS
AROUND 49 TO 51F WILL OBVIOUSLY KEEP TEMPERATURES UP, AND A LOOK AT
THE RECORD BOOK FOR DODGE CITY REVEALS THAT THE DECEMBER 13
CALENDAR DAY RECORD HIGH-MINIMUM TEMPERATURE OF 42 DEGREES WILL
FALL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 300 AM CST SAT DEC 13 2014
SUNDAY:
AN ACTIVE WEATHER DAY ON SUNDAY WITH A SYNOPTIC WAVE TRAVERSING THE
REGION AND A FAIRLY WRAPPED UP LOW LEVEL CYCLONE PASSING ACROSS THE
CENTRAL AND SOUTHERN PLAINS. FORECAST REFLECTIVITY FROM THE 4 KM NAM
AND WRF-ARW LOOKS QUITE CONVECTIVE ACROSS THE REGION. THERE WILL BE
INSTABILITY WITH THE 500-HPA MID LEVEL COLD POOL MOVING CLOSER TO THE
FORECAST AREA AND AS LOW LEVEL LAPSE RATES STEEPEN WITH THE DISTURBANCE.
STRONG STORMS CANNOT BE RULED OUT GIVEN THE SHALLOW SUPERCELL NATURE
ENVIRONMENT THAT IS EXPECTED. IN ADDITION, PRECIPITATION LOADING COULD
RESULT TO WINDS BEING DRAGGED DOWN. EVERYTHING IS ON THE LOW END OF
THE SEVERE SPECTRUM, BUT THIS SYSTEM IS IMPRESSIVE FOR DECEMBER STANDARDS.
WHAT IS MORE AMUSING IS THE NAM SHOWS ACTUAL MODERATE FORECAST STP VALUES
ACROSS THE SOUTHERN PLAINS. SOMETHING TO THINK ABOUT BUT PROBABLY IS
OVER FORECAST. THERE WILL BE SOME SNOW ON THE BACKSIDE OF THE CYCLONE
AS INTENSE COLD AIR ADVECTION ENSUES. OVERALL, THE SYNOPTIC WAVE IS
WARM WITH POSITIVE TEMPERATURE ANOMALIES. THINK THAT THE OVERALL SNOWFALL
POTENTIAL IS MORE ON THE MARGINAL SIDE AND AMOUNTS SHOULD BE BELOW ADVISORY
THRESHOLD. THE MORE PRESSING ISSUES IS THUNDERSTORM THREAT WITH THE
REGION SEEING A DECENT SHOT AT LIQUID PRECIPITATION AMOUNTS.
MONDAY:
A TIGHT PRESSURE GRADIENT BEHIND THE LOW/FRONT WILL RESULT IN BREEZY
WINDS ACROSS THE REGION MONDAY AND MUCH COOLER TEMPERATURES IN THE WAKE
OF THE FRONT. THE FORECAST IS DRY AS SUBSIDENCE CONTINUES IN THE WAKE
OF THE SYNOPTIC WAVE. HIGHS WILL BE IN THE 40S AND LOWS IN THE 20S HEADING
INTO TUESDAY MORNING.
AND THE REST:
THE NEXT CHANCE FOR PRECIPITATION COMES WEDNESDAY NIGHT INTO THURSDAY.
FORECAST UNCERTAINTY IS LARGE AT THIS POINT SO STUCK WITH THE SUPERBLEND
SOLUTION DURING THIS PERIOD AND FOR THE REST OF THE FORECAST PERIOD.
TEMPERATURES WILL BE FAIRLY CLOSE TO SEASONAL NORMS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 500 AM CST SAT DEC 13 2014
LIFR CONDITIONS AGAIN THIS MORNING WITH FOG AND REDUCED VIS. SOME
IMPROVEMENT IN VIS LATER THIS MORNING, BUT STILL LOW CIGS. FOG AND
REDUCTION OF FLIGHT CATEGORY ONCE AGAIN THIS EVENING WITH REDEVELOPMENT
OF FOG.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 56 52 56 34 / 10 10 90 20
GCK 58 50 54 30 / 10 30 90 60
EHA 66 47 54 29 / 0 50 60 30
LBL 66 52 57 31 / 10 50 60 20
HYS 55 51 56 33 / 10 10 90 80
P28 59 56 58 38 / 10 10 90 40
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
KSZ043>045-061>066-074>081-084>090.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...SUGDEN
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
258 AM CST SAT DEC 13 2014
...UPDATE TO LONG TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 251 AM CST SAT DEC 13 2014
OVERNIGHT WEATHER REMAINED VERY FOGGY WITH ONE-QUARTER MILE OR LESS
VISIBILITY BEING OBSERVED OVER A FAIRLY LARGE PORTION OF SOUTHWEST
KANSAS. SURFACE ANALYSIS OVERNIGHT SHOWED THE 50F ISODROSOTHERM JUST
SOUTH OF THE KANSAS BORDER WITH MUCH OF THE SOUTHWEST KANSAS REGION
SITTING AT A DEWPOINT OF 46 TO 48F. WE WILL CONTINUE THE DENSE FOG
ADVISORY THROUGH THE LATE MORNING HOURS. SOME FINE-TUNING OF THE
FOG ADVISORY WILL BE NEEDED AFTER SUNRISE AS THE DENSE FOG AREA
SHRINKS. IT APPEARS THE BEST AREA TO KEEP FOG IN PLACE THROUGH
MIDDAY WILL BE SOUTH OF THE ARKANSAS RIVER AND EAST OF HIGHWAY
83...WITH THE LATEST HOURLY HRRR MODEL SUGGESTING ONE-QUARTER MILE
VISIBILITY HOLDING STRONG IN THESE AREAS THROUGH NOON.
AS THE UPPER LEVEL TROUGH CONTINUES TO PUSH EAST TODAY, WE WILL SEE
LOW LEVEL FLOW START TO VEER SOMEWHAT ON THE HIGH PLAINS. THIS WILL
ALLOW DEEPER MIXING OVER THE HIGH PLAINS WITH BETTER MOMENTUM
TRANSFER OUT WEST...ALLOWING THE WESTERN EDGE OF THE LOW STRATUS TO
SHIFT EAST BY AFTERNOON. THE BEST FORECAST FOR THE EDGE OF THE LOW
STRATUS BY MID-AFTERNOON IS ROUGHLY A DIGHTON TO CIMARRON TO MEADE
LINE (GIVE OR TAKE 20 OR 30 MILES). THIS WILL OBVIOUSLY HAVE AN
IMPACT ON TEMPERATURES, BUT EVEN WITH THE STRATUS ERODING,
HIGH CIRROSTRATUS WILL BE INCREASING FROM THE WEST, SO THIS WOULD
CURB THE WARM UP A BIT. NEVERTHELESS, WARMEST TEMPERATURES WILL BE
OUT IN THE FAR SOUTHWEST TODAY WITH HIGHS IN THE MID 60S AT ELKHART
AND LIBERAL. AREAS THAT REMAIN IN THE STRATUS ALL DAY FARTHER EAST
AND NORTH...TEMPERATURES WILL NOT GET ABOVE THE MID 50S.
DENSE FOG WILL LIKELY REDEVELOP AS SURFACE FLOW BACKS A BIT AFTER
SUNSET. AGAIN, WIDESPREAD VISIBILITIES OF ONE-QUARTER MILE OR LESS
APPEAR LIKELY, ESPECIALLY AT THE EDGE OF THE DIURNAL STRATUS SHIELD.
DEEPER MOISTURE WILL BE ADVANCING NORTHWARD FROM THE TEXAS PANHANDLE
IN THE 09-12Z TIME FRAME, LEADING TO SHOWER AND ISOLATED
THUNDERSTORM DEVELOPMENT. THE 4KM NAM AND WRF-ARW SUGGEST THE FIRST
SHOWERS AND ISOLATED THUNDERSTORMS MOVING INTO THE ELKHART TO
LIBERAL AREAS SHORTLY BEFORE SUNRISE SUNDAY MORNING...AND BECOMING
MORE NUMEROUS IN NATURE LATER IN THE MORNING (DISCUSSED FURTHER IN
THE LONG TERM SECTION).
AS FAR AS TEMPERATURES GO TONIGHT, THE ABNORMALLY HIGH DEWPOINTS
AROUND 49 TO 51F WILL OBVIOUSLY KEEP TEMPERATURES UP, AND A LOOK AT
THE RECORD BOOK FOR DODGE CITY REVEALS THAT THE DECEMBER 13
CALENDAR DAY RECORD HIGH-MINIMUM TEMPERATURE OF 42 DEGREES WILL
FALL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 300 AM CST SAT DEC 13 2014
SUNDAY:
AN ACTIVE WEATHER DAY ON SUNDAY WITH A SYNOPTIC WAVE TRAVERSING THE
REGION AND A FAIRLY WRAPPED UP LOW LEVEL CYCLONE PASSING ACROSS THE
CENTRAL AND SOUTHERN PLAINS. FORECAST REFLECTIVITY FROM THE 4 KM NAM
AND WRF-ARW LOOKS QUITE CONVECTIVE ACROSS THE REGION. THERE WILL BE
INSTABILITY WITH THE 500-HPA MID LEVEL COLD POOL MOVING CLOSER TO THE
FORECAST AREA AND AS LOW LEVEL LAPSE RATES STEEPEN WITH THE DISTURBANCE.
STRONG STORMS CANNOT BE RULED OUT GIVEN THE SHALLOW SUPERCELL NATURE
ENVIRONMENT THAT IS EXPECTED. IN ADDITION, PRECIPITATION LOADING COULD
RESULT TO WINDS BEING DRAGGED DOWN. EVERYTHING IS ON THE LOW END OF
THE SEVERE SPECTRUM, BUT THIS SYSTEM IS IMPRESSIVE FOR DECEMBER STANDARDS.
WHAT IS MORE AMUSING IS THE NAM SHOWS ACTUAL MODERATE FORECAST STP VALUES
ACROSS THE SOUTHERN PLAINS. SOMETHING TO THINK ABOUT BUT PROBABLY IS
OVER FORECAST. THERE WILL BE SOME SNOW ON THE BACKSIDE OF THE CYCLONE
AS INTENSE COLD AIR ADVECTION ENSUES. OVERALL, THE SYNOPTIC WAVE IS
WARM WITH POSITIVE TEMPERATURE ANOMALIES. THINK THAT THE OVERALL SNOWFALL
POTENTIAL IS MORE ON THE MARGINAL SIDE AND AMOUNTS SHOULD BE BELOW ADVISORY
THRESHOLD. THE MORE PRESSING ISSUES IS THUNDERSTORM THREAT WITH THE
REGION SEEING A DECENT SHOT AT LIQUID PRECIPITATION AMOUNTS.
MONDAY:
A TIGHT PRESSURE GRADIENT BEHIND THE LOW/FRONT WILL RESULT IN BREEZY
WINDS ACROSS THE REGION MONDAY AND MUCH COOLER TEMPERATURES IN THE WAKE
OF THE FRONT. THE FORECAST IS DRY AS SUBSIDENCE CONTINUES IN THE WAKE
OF THE SYNOPTIC WAVE. HIGHS WILL BE IN THE 40S AND LOWS IN THE 20S HEADING
INTO TUESDAY MORNING.
AND THE REST:
THE NEXT CHANCE FOR PRECIPITATION COMES WEDNESDAY NIGHT INTO THURSDAY.
FORECAST UNCERTAINTY IS LARGE AT THIS POINT SO STUCK WITH THE SUPERBLEND
SOLUTION DURING THIS PERIOD AND FOR THE REST OF THE FORECAST PERIOD.
TEMPERATURES WILL BE FAIRLY CLOSE TO SEASONAL NORMS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1144 PM CST FRI DEC 12 2014
WIDESPREAD LIFR AND PERIODS OF VLIFR WILL CONTINUE THROUGH THE
NIGHT AND INTO THE DAY SATURDAY AS ABNORMALLY HIGH LOW LEVEL
MOISTURE CONTINUES ACROSS SOUTHERN AND WESTERN KANSAS. WIND SPEEDS
HAVE PICKED UP A BIT FROM THE SOUTH-SOUTHEAST AND WILL AVERAGE 12
TO 15 KNOTS THROUGH THE FORECAST PERIOD. THE FORECAST AT GCK IS
PROBLEMATIC IN THAT BY AFTERNOON SATURDAY, THE WESTERN EDGE OF THE
LIFR STRATUS WILL MIX EASTWARD. THE OFFICIAL FORECAST CALLS FOR A
FEW HOURS OF VFR AT GCK IN THE LATE AFTERNOON HOURS, BUT THIS IS
ACTUALLY FAIRLY LOW CONFIDENCE. EVEN IF IT DOES SCATTER OUT TO VFR
IN THE AFTERNOON, THE LIFR/VLIFR CONDITIONS WILL ROLL BACK IN AT
SUNSET OR SHORTLY THEREAFTER.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 56 52 56 34 / 10 10 90 20
GCK 58 50 54 30 / 10 30 90 60
EHA 66 47 54 29 / 0 50 60 30
LBL 66 52 57 31 / 10 50 60 20
HYS 55 51 56 33 / 10 10 90 80
P28 59 56 58 38 / 10 10 90 40
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
KSZ043>045-061>066-074>081-084>090.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...SUGDEN
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
252 AM CST SAT DEC 13 2014
...UPDATED SHORT TERM SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 251 AM CST SAT DEC 13 2014
OVERNIGHT WEATHER REMAINED VERY FOGGY WITH ONE-QUARTER MILE OR LESS
VISIBILITY BEING OBSERVED OVER A FAIRLY LARGE PORTION OF SOUTHWEST
KANSAS. SURFACE ANALYSIS OVERNIGHT SHOWED THE 50F ISODROSOTHERM JUST
SOUTH OF THE KANSAS BORDER WITH MUCH OF THE SOUTHWEST KANSAS REGION
SITTING AT A DEWPOINT OF 46 TO 48F. WE WILL CONTINUE THE DENSE FOG
ADVISORY THROUGH THE LATE MORNING HOURS. SOME FINE-TUNING OF THE
FOG ADVISORY WILL BE NEEDED AFTER SUNRISE AS THE DENSE FOG AREA
SHRINKS. IT APPEARS THE BEST AREA TO KEEP FOG IN PLACE THROUGH
MIDDAY WILL BE SOUTH OF THE ARKANSAS RIVER AND EAST OF HIGHWAY
83...WITH THE LATEST HOURLY HRRR MODEL SUGGESTING ONE-QUARTER MILE
VISIBILITY HOLDING STRONG IN THESE AREAS THROUGH NOON.
AS THE UPPER LEVEL TROUGH CONTINUES TO PUSH EAST TODAY, WE WILL SEE
LOW LEVEL FLOW START TO VEER SOMEWHAT ON THE HIGH PLAINS. THIS WILL
ALLOW DEEPER MIXING OVER THE HIGH PLAINS WITH BETTER MOMENTUM
TRANSFER OUT WEST...ALLOWING THE WESTERN EDGE OF THE LOW STRATUS TO
SHIFT EAST BY AFTERNOON. THE BEST FORECAST FOR THE EDGE OF THE LOW
STRATUS BY MID-AFTERNOON IS ROUGHLY A DIGHTON TO CIMARRON TO MEADE
LINE (GIVE OR TAKE 20 OR 30 MILES). THIS WILL OBVIOUSLY HAVE AN
IMPACT ON TEMPERATURES, BUT EVEN WITH THE STRATUS ERODING,
HIGH CIRROSTRATUS WILL BE INCREASING FROM THE WEST, SO THIS WOULD
CURB THE WARM UP A BIT. NEVERTHELESS, WARMEST TEMPERATURES WILL BE
OUT IN THE FAR SOUTHWEST TODAY WITH HIGHS IN THE MID 60S AT ELKHART
AND LIBERAL. AREAS THAT REMAIN IN THE STRATUS ALL DAY FARTHER EAST
AND NORTH...TEMPERATURES WILL NOT GET ABOVE THE MID 50S.
DENSE FOG WILL LIKELY REDEVELOP AS SURFACE FLOW BACKS A BIT AFTER
SUNSET. AGAIN, WIDESPREAD VISIBILITIES OF ONE-QUARTER MILE OR LESS
APPEAR LIKELY, ESPECIALLY AT THE EDGE OF THE DIURNAL STRATUS SHIELD.
DEEPER MOISTURE WILL BE ADVANCING NORTHWARD FROM THE TEXAS PANHANDLE
IN THE 09-12Z TIME FRAME, LEADING TO SHOWER AND ISOLATED
THUNDERSTORM DEVELOPMENT. THE 4KM NAM AND WRF-ARW SUGGEST THE FIRST
SHOWERS AND ISOLATED THUNDERSTORMS MOVING INTO THE ELKHART TO
LIBERAL AREAS SHORTLY BEFORE SUNRISE SUNDAY MORNING...AND BECOMING
MORE NUMEROUS IN NATURE LATER IN THE MORNING (DISCUSSED FURTHER IN
THE LONG TERM SECTION).
AS FAR AS TEMPERATURES GO TONIGHT, THE ABNORMALLY HIGH DEWPOINTS
AROUND 49 TO 51F WILL OBVIOUSLY KEEP TEMPERATURES UP, AND A LOOK AT
THE RECORD BOOK FOR DODGE CITY REVEALS THAT THE DECEMBER 13
CALENDAR DAY RECORD HIGH-MINIMUM TEMPERATURE OF 42 DEGREES WILL
FALL.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 301 PM CST FRI DEC 12 2014
THE MODELS, EXCEPT FOR THE NAM, ARE CONVERGING ON A SOLUTION WITH
SUNDAY`S UPPER LEVEL STORM SYSTEM, MOVING ALONG A PATH FROM
DALHART TO WICHITA TO KANSAS CITY. THIS TRACK WOULD RESULT IN A
BAND OF SHOWERS AND ISOLATED THUNDERSTORMS WITH THE WARM CONVEYOR
BELT AHEAD OF THE SYSTEM SUNDAY MORNING AND EARLY SUNDAY
AFTERNOON, THEN SOME RAIN CHANGING TO SNOW SUNDAY NIGHT INTO EARLY
MONDAY NEAR THE TROWEL AXIS FROM STANTON COUNTY INTO SCOTT, LANE
AND TREGO COUNTIES. THE BEST CHANCE OF SUBSTANTIAL RAINFALL WILL
BE ALONG AND EAST OF A LINE FROM DIGHTON TO DODGE CITY TO
ENGLEWOOD. GIVEN THE LOW CLOUDINESS AND HIGH DEWPOINTS,
TEMPERATURES ARE NOT EXPECTED TO CHANGE MORE THAN SEVERAL DEGREES
UNTIL THE COLD FRONT PASSES SUNDAY EVENING, MAINLY STAYING IN THE
50S SATURDAY NIGHT AND SUNDAY.
THE NEXT FORECAST PROBLEM IS A LARGE UPPER LEVEL TROUGH
APPROACHING THE PLAINS BY LATE WEDNESDAY THROUGH FRIDAY. THE
MODELS HAVE A WIDE VARIETY OF SOLUTIONS SO THAT THE DETAILS
ARE NOT KNOWN. BUT THERE IS A CHANCE OF RAIN OR SNOW THROUGH THIS
PERIOD GIVEN THAT WEAK SURFACE HIGH PRESSURE IS ADVERTISED TO
KEEP CHILLY, ALBEIT NOT ARCTIC, AIR IN PLACE ACROSS WESTERN KANSAS.
YET ANOTHER STORM SYSTEM MAY AFFECT WESTERN KANSAS BY THE DECEMBER
22ND-24TH TIME FRAME; AND THE DETAILS OF THIS SYSTEM OF COURSE ARE
EVEN LESS KNOWN. TEMPERATURES THROUGH THIS PERIOD WILL PROBABLY
STAY CLOSE TO SEASONAL AVERAGES OR PERHAPS A LITTLE COLDER THAN
AVERAGE SO THAT RAIN OR SNOW WOULD BE POSSIBLE WITH ANY APPROACHING
STORM SYSTEM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1144 PM CST FRI DEC 12 2014
WIDESPREAD LIFR AND PERIODS OF VLIFR WILL CONTINUE THROUGH THE
NIGHT AND INTO THE DAY SATURDAY AS ABNORMALLY HIGH LOW LEVEL
MOISTURE CONTINUES ACROSS SOUTHERN AND WESTERN KANSAS. WIND SPEEDS
HAVE PICKED UP A BIT FROM THE SOUTH-SOUTHEAST AND WILL AVERAGE 12
TO 15 KNOTS THROUGH THE FORECAST PERIOD. THE FORECAST AT GCK IS
PROBLEMATIC IN THAT BY AFTERNOON SATURDAY, THE WESTERN EDGE OF THE
LIFR STRATUS WILL MIX EASTWARD. THE OFFICIAL FORECAST CALLS FOR A
FEW HOURS OF VFR AT GCK IN THE LATE AFTERNOON HOURS, BUT THIS IS
ACTUALLY FAIRLY LOW CONFIDENCE. EVEN IF IT DOES SCATTER OUT TO VFR
IN THE AFTERNOON, THE LIFR/VLIFR CONDITIONS WILL ROLL BACK IN AT
SUNSET OR SHORTLY THEREAFTER.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 56 52 56 34 / 10 10 90 20
GCK 58 50 54 30 / 10 30 90 60
EHA 66 47 54 29 / 0 50 60 30
LBL 66 52 57 31 / 10 50 60 20
HYS 55 51 56 33 / 10 10 90 80
P28 59 56 58 38 / 10 10 90 40
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR
KSZ043>045-061>066-074>081-084>090.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...FINCH
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
337 PM CST FRI DEC 12 2014
...UPDATED FOR LONG TERM DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 1212 AM CST FRI DEC 12 2014
THIS MORNING:
SOME LOCATIONS LIKE KDDC HAVE BEEN GOING IN AND OUT OF FOG ADVISORY
CRITERIA, WHILE OTHER SITES OUT WEST STILL INDICATE DENSE FOG. IN ORDER
TO AVOID SPLITTING HAIRS, WILL CONTINUE THE ADVISORY AS IS AND EVEN
HAVE EXTENDED IN TIME AS THE FOG MAY LINGER LONGER THAN WHAT MODELS
ARE INDICATING. PUSHED THE EXPIRATION TIME OUT ANOTHER 2 HOURS. ABUNDANT
LOW LEVEL MOISTURE AND HRRR GUIDANCE STILL SUGGEST THAT A GOOD CHUNK
OF THE ADVISORY AREA WILL SEE DENSE FOG THROUGH LATE MORNING.
TODAY:
HAVE UNDERCUT GUIDANCE AGAIN WITH TEMPERATURES DUE TO FOG. HOWEVER,
THINK THAT LINGERING FOG WILL RESULT IN LOWER HIGHS LIKE WE SAW YESTERDAY.
UPSLOPE FOG SHOULD LINGER THEN LONGEST ACROSS THE WESTERN ZONES AND
HAVE GONE LOWER HERE. CALLING FOR 40S WEST TO 50S EAST. SOME
GUIDANCE IS ACTUALLY COOLER, WHILE OTHER GUIDANCE IS WARMER. SOME OF
THE MODELS MIGHT BE TOO AGGRESSIVE WITH FOG DECAY AND RESULTANT
WARMER SURFACE TEMPERATURES. BOTTOM LINE, ANOTHER TRICKY TEMPERATURE
DAY.
TONIGHT:
ANOTHER FOGGY NIGHT IS EXPECTED WITH SOME AREAS SEEING DENSE FOG AS
INDICATED PER FORECAST SOUNDINGS AND BUFKIT PLUMES. WILL KEEP FOG
IN THE GRIDS. THE NORTHERN AND EASTERN ZONES MAY SEE ENOUGH SATURATION
THICKNESS FOR PATCHY DRIZZLE, HOWEVER, LOOKS MORE OF FOG THAN DRIZZLE.
MINIMUMS WILL BE MILD AGAIN WITH THE FOG, HIGHER DEWPOINTS, AND CLOUD
COVER - 40S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 301 PM CST FRI DEC 12 2014
THE MODELS, EXCEPT FOR THE NAM, ARE CONVERGING ON A SOLUTION WITH
SUNDAY`S UPPER LEVEL STORM SYSTEM, MOVING ALONG A PATH FROM
DALHART TO WICHITA TO KANSAS CITY. THIS TRACK WOULD RESULT IN A
BAND OF SHOWERS AND ISOLATED THUNDERSTORMS WITH THE WARM CONVEYOR
BELT AHEAD OF THE SYSTEM SUNDAY MORNING AND EARLY SUNDAY
AFTERNOON, THEN SOME RAIN CHANGING TO SNOW SUNDAY NIGHT INTO EARLY
MONDAY NEAR THE TROWEL AXIS FROM STANTON COUNTY INTO SCOTT, LANE
AND TREGO COUNTIES. THE BEST CHANCE OF SUBSTANTIAL RAINFALL WILL
BE ALONG AND EAST OF A LINE FROM DIGHTON TO DODGE CITY TO
ENGLEWOOD. GIVEN THE LOW CLOUDINESS AND HIGH DEWPOINTS,
TEMPERATURES ARE NOT EXPECTED TO CHANGE MORE THAN SEVERAL DEGREES
UNTIL THE COLD FRONT PASSES SUNDAY EVENING, MAINLY STAYING IN THE
50S SATURDAY NIGHT AND SUNDAY.
THE NEXT FORECAST PROBLEM IS A LARGE UPPER LEVEL TROUGH
APPROACHING THE PLAINS BY LATE WEDNESDAY THROUGH FRIDAY. THE
MODELS HAVE A WIDE VARIETY OF SOLUTIONS SO THAT THE DETAILS
ARE NOT KNOWN. BUT THERE IS A CHANCE OF RAIN OR SNOW THROUGH THIS
PERIOD GIVEN THAT WEAK SURFACE HIGH PRESSURE IS ADVERTISED TO
KEEP CHILLY, ALBEIT NOT ARCTIC, AIR IN PLACE ACROSS WESTERN KANSAS.
YET ANOTHER STORM SYSTEM MAY AFFECT WESTERN KANSAS BY THE DECEMBER
22ND-24TH TIME FRAME; AND THE DETAILS OF THIS SYSTEM OF COURSE ARE
EVEN LESS KNOWN. TEMPERATURES THROUGH THIS PERIOD WILL PROBABLY
STAY CLOSE TO SEASONAL AVERAGES OR PERHAPS A LITTLE COLDER THAN
AVERAGE SO THAT RAIN OR SNOW WOULD BE POSSIBLE WITH ANY APPROACHING
STORM SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1140 AM CST FRI DEC 12 2014
WIDESPREAD STRATUS AND FOG WILL REMAIN THE BIG STORY FOR THE DDC,
GCK, AND HYS TERMINALS THROUGH THE NEXT 24 HOURS. SLOWLY DEEPENING
LEE TROUGH OVER FAR EASTERN COLORADO WILL KEEP A COLD FRONT
STALLED NEAR THE KANSAS...COLORADO BORDER. THIS WILL ALLOW A
COOL...MOIST SOUTHEAST UPSLOPE FLOW ON THE EAST SIDE OF THIS
FRONT TO REMAIN IN PLACE WITH REDEVELOPMENT OF LIFR TO VLIFR
CEILINGS AND VISIBILITIES EXPECTED THIS EVENING TO OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 48 58 54 58 / 10 10 20 80
GCK 46 58 48 54 / 10 10 30 40
EHA 40 65 44 54 / 0 0 30 40
LBL 47 66 52 57 / 10 10 50 50
HYS 47 55 52 57 / 10 10 10 90
P28 49 59 54 60 / 10 10 10 90
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY FROM 9 PM CST /8 PM MST/ THIS EVENING TO NOON
CST /11 AM MST/ SATURDAY FOR KSZ043>045-061>066-074>081-084>090.
&&
$$
SHORT TERM...SUGDEN
LONG TERM...FINCH
AVIATION...AJOHNSON
AREA FORECAST DISCUSSION
NWS TOPEKA KS
324 PM CST Fri Dec 12 2014
.SHORT TERM...(This Evening through Saturday)
Issued at 324 PM CST FRI DEC 12 2014
20Z water vapor imagery continues to show mid level ridging over the
great plains with a weak shortwave moving southeast over eastern OK.
Meanwhile the longwave trough out west is making steady progress
inland. At the surface, ridging over the lower MS river valley and
low pressure in the lee of the Rockies continues to favor the
continued advection of moist air north. Surface obs are now showing
the lower 50 dewpoints beginning to surge north through western OK
and the eastern TX panhandle.
For tonight and Saturday, the models show little if any large scale
forcing as the mid level ridge remains overhead. Because of this the
forecast focuses mainly on the low level moisture return and keeps
chances for measurable precip at 10 percent or less. Overcast skies
are likely to take hold once again this evening due to the low level
moisture advection. Already lower clouds have moved back north to
along I-70 after some mid level subsidence behind the upper level
shortwave caused the clouds to dissipate. Based on the models, there
is not much to suggest the trend for clouds spreading north will go
away. Am not sure how wide spread any drizzle overnight will be
since forecast soundings from the RAP/NAM/GFS show only very weak
vertical motion within the stratus deck. Isentropic surfaces are
also very shallow with any upglide and it does not seem to be well
organized for an extended period of time. Because of this will only
mention patchy fog and drizzle. With cloud cover and moisture
continuing to move north, lows tonight are expected to remain in the
mid 40s, and this possibly could be a little on the cool side. The
question for highs Saturday is whether there will be much insolation.
Models continue to move the weak shortwave away from the forecast
area, so am not sure there will be the subsidence we had today to
erode the clouds away. Nevertheless continued warm air advection
should help push temps into the mid 50s to around 60.
.LONG TERM...(Saturday Night through Friday)
Issued at 324 PM CST FRI DEC 12 2014
Chances for more significant precipitation still set to increase
Sunday into Sunday night as the upper wave steadily deepens and
finally passes through Sunday night. There remain some differences
on specifics of this system in speed and location, at least in part
due to interaction with northern branch jet energy coming south into
the Northern Plains behind it, with the main impact of this on the
amount of cold air that can be pulled in behind the stacked system
and how fast precip will exit. Deep cold air availability still
remains a challenge in even the stronger slower/stronger solutions,
still only supporting a mix mention in western locations Monday
morning. Depending on this depth, could see nearly any mode of
wintry precip develop, with any amounts being light, and given such
warm conditions in preceding days, impacts are expected to be
minimal. As for this warmth, deep south flow to slightly southwest
flow continues to push and low to mid level thermodynamics up ahead
of the system. Minor 850mb to near surface isentropic upglide under
the inversion suggests keeping a mention of fog and drizzle going
Saturday night into Sunday morning. Mixing heights from model
soundings look a little too given increasing pressure gradient, and
could see some breaks in the low cloud to bring highs into the lower
60s, with Saturday night dewpoints in the 50s keeping temps well
above normal high temps. Forcing aloft and a bit of instability
aloft keeps a thunder mention in for Sunday afternoon and at least
Sunday evening, though expect a slow downturn in intensity overnight
Sunday, with wettest period late Sunday afternoon into the predawn
of Monday.
Tuesday into at least early Wednesday are the best bets to be dry
for this forecast, with uncertainty in the forecast increasing with
time. Energy with the upper trough north of Hawaii today makes its
way into the western CONUS early next week, splitting in various
ways in the stronger southern branch and still considerable northern
branch jets into the mid week. The GFS has the Monday Northern
Plains low weaker and faster than the ECMWF, allowing for a
southwest shortwave to intensify and tap into better moisture. It
appears to be the outlier from recent runs and will keep Wednesday
dry. There is an overall more southern trend with the storm track
into the late week and with modified Canadian air keeping hold of
the Northern Plains, have decreasing confidence in getting
precipitation, especially anything heavy, into the end of the work
week. Temperature should remain rather close to seasonable
normals.
&&
.AVIATION...(For the 18Z TAFs through 18Z Saturday Afternoon)
Issued at 1114 AM CST FRI DEC 12 2014
The forecast will stay with persistence as the RAP and NAM
continue to show a relative minimum in 925MB RH through the
afternoon. Because of this think VFR CIGS will persist with VSBY
gradually improving. May even see the sucker hole to the north
move over the terminals this afternoon. Forecast soundings and
objective MOS guidance continues to point at MVFR conditions
redeveloping this evening. With IFR CIGS and VSBY upstream over
southern KS and northwest OK, this seems reasonable. Confidence in
timing the lower CIGS and VSBY is not that high since models show
a saturated boundary layer even now.
&&
.CLIMATE...
Issued at 324 PM CST FRI DEC 12 2014
Record high temperatures for December 13...
Topeka......70, set in 1921.
Concordia...75, set in 1921.
Record highest minimum temperatures for December 13...
Topeka......42, set in 2008.
Concordia...40, set in 1921.
Record high temperatures for December 14...
Topeka......70, set in 1933.
Concordia...64, set in 2006.
Record highest minimum temperatures for December 14...
Topeka......46, set in 2011.
Concordia...41, set in 1891.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Wolters
LONG TERM...65
AVIATION...Wolters
CLIMATE...65
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1151 AM CST FRI DEC 12 2014
...UPDATED AVIATION SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 1212 AM CST FRI DEC 12 2014
THIS MORNING:
SOME LOCATIONS LIKE KDDC HAVE BEEN GOING IN AND OUT OF FOG ADVISORY
CRITERIA, WHILE OTHER SITES OUT WEST STILL INDICATE DENSE FOG. IN ORDER
TO AVOID SPLITTING HAIRS, WILL CONTINUE THE ADVISORY AS IS AND EVEN
HAVE EXTENDED IN TIME AS THE FOG MAY LINGER LONGER THAN WHAT MODELS
ARE INDICATING. PUSHED THE EXPIRATION TIME OUT ANOTHER 2 HOURS. ABUNDANT
LOW LEVEL MOISTURE AND HRRR GUIDANCE STILL SUGGEST THAT A GOOD CHUNK
OF THE ADVISORY AREA WILL SEE DENSE FOG THROUGH LATE MORNING.
TODAY:
HAVE UNDERCUT GUIDANCE AGAIN WITH TEMPERATURES DUE TO FOG. HOWEVER,
THINK THAT LINGERING FOG WILL RESULT IN LOWER HIGHS LIKE WE SAW YESTERDAY.
UPSLOPE FOG SHOULD LINGER THEN LONGEST ACROSS THE WESTERN ZONES AND
HAVE GONE LOWER HERE. CALLING FOR 40S WEST TO 50S EAST. SOME
GUIDANCE IS ACTUALLY COOLER, WHILE OTHER GUIDANCE IS WARMER. SOME OF
THE MODELS MIGHT BE TOO AGGRESSIVE WITH FOG DECAY AND RESULTANT
WARMER SURFACE TEMPERATURES. BOTTOM LINE, ANOTHER TRICKY TEMPERATURE
DAY.
TONIGHT:
ANOTHER FOGGY NIGHT IS EXPECTED WITH SOME AREAS SEEING DENSE FOG AS
INDICATED PER FORECAST SOUNDINGS AND BUFKIT PLUMES. WILL KEEP FOG
IN THE GRIDS. THE NORTHERN AND EASTERN ZONES MAY SEE ENOUGH SATURATION
THICKNESS FOR PATCHY DRIZZLE, HOWEVER, LOOKS MORE OF FOG THAN DRIZZLE.
MINIMUMS WILL BE MILD AGAIN WITH THE FOG, HIGHER DEWPOINTS, AND CLOUD
COVER - 40S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 434 AM CST FRI DEC 12 2014
SATURDAY-SATURDAY NIGHT: AHEAD OF THE STORM.
AREAS OF FOG AND DRIZZLE WILL PERSIST THROUGH THE PERIOD ON
CONTINUED SOUTH-SOUTHEAST WINDS. LATE IN THE DAY, HOWEVER, SOME
SOUTHWESTERLY MOMENTUM WILL BEGIN TO IMPINGE ON FAR SOUTHWEST
KANSAS, ALLOWING THE STRATUS TO ERODE. AFTERNOON TEMPERATURES IN
AREAS LIKE ELKHART AND LIBERAL MAY EXCEED 60 DEGREES IF SOME SUN CAN
BE REALIZED AFTER NOON. OTHERWISE THE REST OF THE REGION WILL STAY
SOCKED IN WITH TEMPERATURES NEARLY STEADY IN THE MID 50S AS A
GENERAL RULE. THE MAJOR TROUGH OUT WEST WILL PUSH EAST INTO THE
ROCKIES BY SATURDAY NIGHT. THE ECMWF, GFS, AND CANADIAN GEM ALL
AGREE ON THE PLACEMENT OF THE MAJOR MID-LEVEL POTENTIAL VORTICITY
ANOMALY AT THE BASE OF THE TROUGH FROM CENTRAL ARIZONA EARLY IN THE
EVENING TO CENTRAL/SOUTHERN NEW MEXICO BY THE OVERNIGHT HOURS. THIS
WILL SPONSOR CONTINUED LOW LEVEL CYCLOGENESIS ALONG THE LEE TROUGH
ACROSS SOUTHEASTERN COLORADO, EFFECTIVELY INCREASING THE SOUTHERLY
WINDS. NOCTURNAL TEMPERATURES WILL NOT MOVE MUCH OFF THE DIURNAL
TEMPERATURES WITH EARLY SUNDAY MORNING LOWS ONLY IN THE LOWER TO MID
50S EAST OF HIGHWAY 83.
SUNDAY: THE MAIN PRECIPITATION EVENT.
BY 12Z SUNDAY, THE 500MB LOW WILL CONTINUE TO DEEPEN WITH LATEST
MODEL CONSENSUS OF THE LOW CENTER SOMEWHERE ACROSS NORTHEASTERN NEW
MEXICO...AND A 700MB LOW ALONG THE EASTERN COLORADO-NEW MEXICO
BORDER. BY THIS TIME, WE SHOULD SEE A FAIRLY DECENT AREA OF SHOWERS
AND THUNDERSTORMS ALREADY UNDERWAY ACROSS THE TEXAS PANHANDLE. THIS
WILL BE THE BEGINNINGS OF A NORTHEASTWARD EXPANDING WARM CONVEYOR
BELT CONVECTIVE PRECIPITATION AXIS, WHICH WILL MOVE QUICKLY
NORTHEAST ACROSS SOUTHWEST KANSAS, ESPECIALLY DURING THE 12-18Z TIME
FRAME. IT IS INTERESTING THAT THE NAM12 IS ACTUALLY SLOWER THAN THE
ECMWF MODEL, WHICH IS OPPOSITE OF WHAT IS TYPICALLY SEEN FROM PAST
PERFORMANCE OF THE NAM REGARDING UPPER LOWS LIKE THIS. EITHER WAY,
BOTH THE NAM12 AND ECMWF SHOW SIGNIFICANT OCCLUSION OCCURRING DURING
THIS TIME FRAME WITH A DRY INTRUSION WORKING RAPIDLY NORTHWARD
AROUND THE EAST SIDE OF THE 700-500MB LOW CENTERS. IT IS LOOKING
MORE AND MORE LIKE A ONE-SHOT DEAL FOR DECENT ACCUMULATING RAINFALL -
- THE 12 TO 18Z TIME FRAME SUNDAY. THE NAM12 SHOWS 500-700 J/KG OF
MUCAPE WHICH REALLY COMES AS NO SURPRISE GIVEN A) THE 50-53F SURFACE
DEWPOINTS AND B) RAPIDLY COOLING MID LEVEL TEMPERATURES. THE WX
GRIDS WILL REFLECT THIS WITH SHOWERS AND ISOLATED THUNDERSTORMS WITH
THIS MAIN WARM CONVEYOR PRECIPITATION AREA. BY LATE IN THE
AFTERNOON, IT IS NOT UNREASONABLE TO THINK THAT SOME SUN MAY FILTER
IN BEHIND THE MAIN BAND OF MORNING/MIDDAY SHOWERS AND STORMS...AND
IF THAT WERE TO OCCUR, THE ATMOSPHERE WOULD RAPIDLY DESTABILIZE
ALLOWING ADDITIONAL SURFACE-BASED SHOWERS/ISOLATED THUNDERSTORMS TO
FORM WITHIN THE MID LEVEL DRY INTRUSION.
SUNDAY NIGHT-EARLY MONDAY: THE WRAP-AROUND AND CHANGE OVER TO WET
SNOW.
THE MID LEVEL CYCLONE WILL BE OCCLUDING AND FILLING FAST SUNDAY
NIGHT WITH THE 700MB LOW CENTERED SOMEWHERE ACROSS SOUTHWEST KANSAS.
WITH THE LOW CENTERED AT THIS LATITUDE, THE BEST AREA FOR WRAP-
AROUND COLD SECTOR DEFORMATION ZONE PRECIPITATION WILL BE ACROSS
NORTHWEST KANSAS AND ADJACENT EAST-CENTRAL/NORTHEAST COLORADO. THE
HIGHEST EVENING POPS WILL BE CONFINED TO FAR WEST-CENTRAL KANSAS
(SYRACUSE UP TO SCOTT CITY MAINLY). THE SOUTHERN PART OF THE WRAP-
AROUND PRECIPITATION SHIELD IN THE COLD SECTOR WILL MOST LIKELY BE
SNOW AS 850MB TEMPERATURES DROP TO -1 TO -3C, ESPECIALLY BY 06Z. BY
THIS TIME, HOWEVER, THE DEFORMATION ZONE IS EXPECTED TO WEAKEN AND
ANY WRAP-AROUND PRECIPITATION SHOULD BE RATHER LIGHT, AND CONFINED
MAINLY TO SYRACUSE-SCOTT CITY-WAKEENEY LINE. THE PROSPECT OF MODERATE
TO EVEN LIGHT ACCUMULATING SNOWFALL (TO CREATE ANY TRAVEL HAZARD)
FOR ANY PORTION OF THE DDC FORECAST AREA HAS DECREASED QUITE A BIT.
IN FACT, WE WON`T BE CARRYING ANY MORE THAN ABOUT A HALF INCH OF
SNOW ANYWHERE IN THE FORECAST AREA, AND THAT WILL ONLY BE UP IN
SCOTT-LANE-TREGO COUNTY.
EARLY WEEK: IN BETWEEN STORM SYSTEMS.
WE WILL SEE SOME SHORTWAVE RIDGING MONDAY NIGHT INTO TUESDAY IN THE
WAKE OF THE FIRST STORM. WE SHOULD ONLY RECEIVE A GLANCING SHOT OF
COOLER CANADIAN AIR, AND IT WILL NOT BE ARCTIC IN NATURE. MONDAY`S
HIGHS SHOULD BE IN THE LOWER TO MID 40S MOST EVERYWHERE WITH
NORTHWEST WINDS 15 TO 25 MPH OR SO (STRONGEST EARLY IN THE DAY).
EYES THEN TURN BACK OUT WEST AS ANOTHER DEEP TROUGH AND PACIFIC JET
DIVES TOWARD THE CALIFORNIA COAST. WE WILL REMAIN IN SHORTWAVE
RIDGING THROUGH WEDNESDAY AS THE NEXT STORM BEGINS TO TAKE SHAPE
ACROSS THE DESERT SOUTHWEST REGION WITH TEMPERATURES SEASONAL IN THE
LOWER 40S FOR HIGHS AND 20S FOR LOWS BOTH TUESDAY AND WEDNESDAY.
MID-LATE WEEK: THE NEXT STORM?
THERE IS A TREMENDOUS AMOUNT OF UNCERTAINTY REGARDING SENSIBLE
WEATHER CONCERNS DURING THE DEC 18-20 TIME FRAME. THE ECMWF
CONTINUES TO BE THE MOST AGGRESSIVE MODEL SUGGESTING A DECENT WINTER
PRECIPITATION EVENT ACROSS PORTIONS OF KANSAS LATE WEDNESDAY NIGHT
THROUGH THURSDAY EVENING. THE LEGACY GFS40 MODEL SHOWS A MUCH WEAKER
INITIAL WAVE AND THUS MUCH LESS DEVELOPMENT FOR PRECIPITATION DURING
THIS TIME FRAME. THE GFS40 FOCUSES MUCH OF ITS ENERGY ON THE SECOND
JET STREAK WHICH DIVES WAY DOWN INTO SOUTHWEST TEXAS. IN THE GRIDS,
WE WILL BE FOLLOWING THE SUPERBLEND GUIDANCE OF 20-30 POPS FOR
WEDNESDAY NIGHT, THURSDAY, THURSDAY NIGHT PERIODS FOR NOW WITH A
VAGUE "RAIN OR SNOW" AS THE WX TYPE RIGHT NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1140 AM CST FRI DEC 12 2014
WIDESPREAD STRATUS AND FOG WILL REMAIN THE BIG STORY FOR THE DDC,
GCK, AND HYS TERMINALS THROUGH THE NEXT 24 HOURS. SLOWLY DEEPENING
LEE TROUGH OVER FAR EASTERN COLORADO WILL KEEP A COLD FRONT
STALLED NEAR THE KANSAS...COLORADO BORDER. THIS WILL ALLOW A
COOL...MOIST SOUTHEAST UPSLOPE FLOW ON THE EAST SIDE OF THIS
FRONT TO REMAIN IN PLACE WITH REDEVELOPMENT OF LIFR TO VLIFR
CEILINGS AND VISIBILITIES EXPECTED THIS EVENING TO OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 53 48 56 54 / 10 10 10 60
GCK 51 45 58 48 / 10 10 10 40
EHA 54 40 65 44 / 0 0 0 30
LBL 51 45 65 52 / 10 10 10 70
HYS 51 46 54 52 / 10 10 10 30
P28 52 48 57 54 / 10 10 10 50
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR KSZ030-
043>045-061>066-074>081-084>090.
&&
$$
SHORT TERM...SUGDEN
LONG TERM...UMSCHEID
AVIATION...AJOHNSON
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1114 AM CST Fri Dec 12 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 335 AM CST FRI DEC 12 2014
In the mid-levels, a broad ridge was in place across the central
U.S. with a closed low centered over the New England area. To the
west, a mid-level trough has developed just off the Pacific
coastline, and it`s this feature that will support rain/snow chances
late weekend into early next week. At the surface the forecast area
remained wedged between high pressure to the east and low pressure
over the Rockies. Model soundings continue to show a strong
inversion in place over the region, which combined with gradual
moisture advection into the area has resulted in moisture remaining
trapped in the low-levels. These conditions have contributed to the
persistent overcast skies and frequent periods of drizzle/mist and
patchy fog. Patchy drizzle and fog were present early this morning,
but model soundings show drier conditions developing within the
low-levels through the morning hours so anticipate a break in the
drizzle by mid morning, if not earlier, and persisting through the
afternoon hours. As the surface high shifts further to the east,
winds are expected to veer toward the south today. Despite the
overcast skies in place, expect these southerly winds to provide
enough warm air advection to boost afternoon high temperatures up
into the upper 40s/low 50s. This southerly flow also will contribute
to continued moisture advection into the area with dewpoint
temperatures rising into the 40s. Model soundings show the dry air
in the low-levels diminishing through the evening and overnight
hours tonight, so expect some areas of drizzle and fog to develop
once again late tonight into Saturday morning. These overcast skies
also will continue to limit the amount of radiational cooling that
occurs in the evening with low temperatures tonight only expected to
drop into the mid/upper 40s.
.LONG TERM...(Saturday through Thursday)
Issued at 335 AM CST FRI DEC 12 2014
The long term period still looks unsettled and the forecast
remains more-or-less unchanged, but perhaps with more confidence
in the details of the storm system late Sunday into Monday.
Saturday through Sunday morning is still on track for continued
cloudy, occasionally foggy conditions with periods of drizzle. The
good news is that Saturday will be quite warm for this time of
year, especially given the cloud cover. The probability for
measurable precipitation through this period is quite low but the
probability of generally wet conditions is rather high.
By mid-day Sunday, the very potent storm system currently lashing
the west coast will be deepening as it moves into the Oklahoma
panhandle region. The upper low will also become a closed low
after crossing the Rockies, which can sometimes signal a slower
progression to the east. This particular system appears to have a
structure that will support continued eastward movement through
Monday, although we have slowed the onset of precipitation locally
with this forecast...with rain not likely to enter the forecast
area until Sunday afternoon. At this time, have moderate
confidence in the track of the storm system being through eastern
KS, and have moderate to high confidence that given this track,
temperature profiles will support rain in the forecast area
through the majority of the storm system. The one exception may be
over north central and far northeast KS as precipitation is
winding down on Monday when some light snow may mix in for a bit.
Much of the forecast area can expect 0.25 to 0.75 inches of liquid
precipitation with this storm system before it exits the area late
Monday. The airmass will be a bit cooler for Tuesday and
Wednesday, closer to normal.
The unsettled weather pattern continues for the foreseeable future
with a steady feed of storm systems moving out of the southwestern
CONUS and into the Plains through day 7 and likely beyond. One of
these storm systems will be scheduled for the end of next week
with substantial uncertainty in how it will evolve. Much of this
uncertainty ties to a separate upper level low that will move
along the US/Canada border during the mid week period. So at this
time, the take-away point with this forecast is to expect
precipitation late next week, and whether it falls as rain or
winter precip is still very much in question.
&&
.AVIATION...(For the 18Z TAFs through 18Z Saturday Afternoon)
Issued at 1114 AM CST FRI DEC 12 2014
The forecast will stay with persistence as the RAP and NAM
continue to show a relative minimum in 925MB RH through the
afternoon. Because of this think VFR CIGS will persist with VSBY
gradually improving. May even see the sucker hole to the north
move over the terminals this afternoon. Forecast soundings and
objective MOS guidance continues to point at MVFR conditions
redeveloping this evening. With IFR CIGS and VSBY upstream over
southern KS and northwest OK, this seems reasonable. Confidence in
timing the lower CIGS and VSBY is not that high since models show
a saturated boundary layer even now.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Hennecke
LONG TERM...Barjenbruch
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS TOPEKA KS
910 AM CST Fri Dec 12 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 335 AM CST FRI DEC 12 2014
In the mid-levels, a broad ridge was in place across the central
U.S. with a closed low centered over the New England area. To the
west, a mid-level trough has developed just off the Pacific
coastline, and it`s this feature that will support rain/snow chances
late weekend into early next week. At the surface the forecast area
remained wedged between high pressure to the east and low pressure
over the Rockies. Model soundings continue to show a strong
inversion in place over the region, which combined with gradual
moisture advection into the area has resulted in moisture remaining
trapped in the low-levels. These conditions have contributed to the
persistent overcast skies and frequent periods of drizzle/mist and
patchy fog. Patchy drizzle and fog were present early this morning,
but model soundings show drier conditions developing within the
low-levels through the morning hours so anticipate a break in the
drizzle by mid morning, if not earlier, and persisting through the
afternoon hours. As the surface high shifts further to the east,
winds are expected to veer toward the south today. Despite the
overcast skies in place, expect these southerly winds to provide
enough warm air advection to boost afternoon high temperatures up
into the upper 40s/low 50s. This southerly flow also will contribute
to continued moisture advection into the area with dewpoint
temperatures rising into the 40s. Model soundings show the dry air
in the low-levels diminishing through the evening and overnight
hours tonight, so expect some areas of drizzle and fog to develop
once again late tonight into Saturday morning. These overcast skies
also will continue to limit the amount of radiational cooling that
occurs in the evening with low temperatures tonight only expected to
drop into the mid/upper 40s.
.LONG TERM...(Saturday through Thursday)
Issued at 335 AM CST FRI DEC 12 2014
The long term period still looks unsettled and the forecast
remains more-or-less unchanged, but perhaps with more confidence
in the details of the storm system late Sunday into Monday.
Saturday through Sunday morning is still on track for continued
cloudy, occasionally foggy conditions with periods of drizzle. The
good news is that Saturday will be quite warm for this time of
year, especially given the cloud cover. The probability for
measurable precipitation through this period is quite low but the
probability of generally wet conditions is rather high.
By mid-day Sunday, the very potent storm system currently lashing
the west coast will be deepening as it moves into the Oklahoma
panhandle region. The upper low will also become a closed low
after crossing the Rockies, which can sometimes signal a slower
progression to the east. This particular system appears to have a
structure that will support continued eastward movement through
Monday, although we have slowed the onset of precipitation locally
with this forecast...with rain not likely to enter the forecast
area until Sunday afternoon. At this time, have moderate
confidence in the track of the storm system being through eastern
KS, and have moderate to high confidence that given this track,
temperature profiles will support rain in the forecast area
through the majority of the storm system. The one exception may be
over north central and far northeast KS as precipitation is
winding down on Monday when some light snow may mix in for a bit.
Much of the forecast area can expect 0.25 to 0.75 inches of liquid
precipitation with this storm system before it exits the area late
Monday. The airmass will be a bit cooler for Tuesday and
Wednesday, closer to normal.
The unsettled weather pattern continues for the foreseeable future
with a steady feed of storm systems moving out of the southwestern
CONUS and into the Plains through day 7 and likely beyond. One of
these storm systems will be scheduled for the end of next week
with substantial uncertainty in how it will evolve. Much of this
uncertainty ties to a separate upper level low that will move
along the US/Canada border during the mid week period. So at this
time, the take-away point with this forecast is to expect
precipitation late next week, and whether it falls as rain or
winter precip is still very much in question.
&&
.AVIATION...(For the 18Z TAFs through 18Z Saturday Afternoon)
Issued at 910 AM CST FRI DEC 12 2014
12Z RAOB from Topeka showed winds just off he surface where from
the southwest and west, which had warmed temps in the 950 to 850MB
layer quite a bit. Think this warming is what reduced the RH in
this layer and allowed CIGS to improve above 3KFT. The RAP and NAM
keep a relative minimum in RH over the terminals through the day.
Therefore have amended the TAFS to keep CIGS VFR. VSBY should
graually improve, but some BR is likely to persist through the
day. CIGS could lower after sunset with some diurnally driven
cooling allowing the low levels to saturate once again, so will
keep a mention of MVFR CIGS after 00Z. Confidence is marginal
since I originally expected CIGS to remain IFR so will keep
monitoring trends.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Hennecke
LONG TERM...Barjenbruch
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
615 AM CST FRI DEC 12 2014
...UPDATED AVIATION SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 1212 AM CST FRI DEC 12 2014
THIS MORNING:
SOME LOCATIONS LIKE KDDC HAVE BEEN GOING IN AND OUT OF FOG ADVISORY
CRITERIA, WHILE OTHER SITES OUT WEST STILL INDICATE DENSE FOG. IN ORDER
TO AVOID SPLITTING HAIRS, WILL CONTINUE THE ADVISORY AS IS AND EVEN
HAVE EXTENDED IN TIME AS THE FOG MAY LINGER LONGER THAN WHAT MODELS
ARE INDICATING. PUSHED THE EXPIRATION TIME OUT ANOTHER 2 HOURS. ABUNDANT
LOW LEVEL MOISTURE AND HRRR GUIDANCE STILL SUGGEST THAT A GOOD CHUNK
OF THE ADVISORY AREA WILL SEE DENSE FOG THROUGH LATE MORNING.
TODAY:
HAVE UNDERCUT GUIDANCE AGAIN WITH TEMPERATURES DUE TO FOG. HOWEVER,
THINK THAT LINGERING FOG WILL RESULT IN LOWER HIGHS LIKE WE SAW YESTERDAY.
UPSLOPE FOG SHOULD LINGER THEN LONGEST ACROSS THE WESTERN ZONES AND
HAVE GONE LOWER HERE. CALLING FOR 40S WEST TO 50S EAST. SOME
GUIDANCE IS ACTUALLY COOLER, WHILE OTHER GUIDANCE IS WARMER. SOME OF
THE MODELS MIGHT BE TOO AGGRESSIVE WITH FOG DECAY AND RESULTANT
WARMER SURFACE TEMPERATURES. BOTTOM LINE, ANOTHER TRICKY TEMPERATURE
DAY.
TONIGHT:
ANOTHER FOGGY NIGHT IS EXPECTED WITH SOME AREAS SEEING DENSE FOG AS
INDICATED PER FORECAST SOUNDINGS AND BUFKIT PLUMES. WILL KEEP FOG
IN THE GRIDS. THE NORTHERN AND EASTERN ZONES MAY SEE ENOUGH SATURATION
THICKNESS FOR PATCHY DRIZZLE, HOWEVER, LOOKS MORE OF FOG THAN DRIZZLE.
MINIMUMS WILL BE MILD AGAIN WITH THE FOG, HIGHER DEWPOINTS, AND CLOUD
COVER - 40S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 434 AM CST FRI DEC 12 2014
SATURDAY-SATURDAY NIGHT: AHEAD OF THE STORM.
AREAS OF FOG AND DRIZZLE WILL PERSIST THROUGH THE PERIOD ON
CONTINUED SOUTH-SOUTHEAST WINDS. LATE IN THE DAY, HOWEVER, SOME
SOUTHWESTERLY MOMENTUM WILL BEGIN TO IMPINGE ON FAR SOUTHWEST
KANSAS, ALLOWING THE STRATUS TO ERODE. AFTERNOON TEMPERATURES IN
AREAS LIKE ELKHART AND LIBERAL MAY EXCEED 60 DEGREES IF SOME SUN CAN
BE REALIZED AFTER NOON. OTHERWISE THE REST OF THE REGION WILL STAY
SOCKED IN WITH TEMPERATURES NEARLY STEADY IN THE MID 50S AS A
GENERAL RULE. THE MAJOR TROUGH OUT WEST WILL PUSH EAST INTO THE
ROCKIES BY SATURDAY NIGHT. THE ECMWF, GFS, AND CANADIAN GEM ALL
AGREE ON THE PLACEMENT OF THE MAJOR MID-LEVEL POTENTIAL VORTICITY
ANOMALY AT THE BASE OF THE TROUGH FROM CENTRAL ARIZONA EARLY IN THE
EVENING TO CENTRAL/SOUTHERN NEW MEXICO BY THE OVERNIGHT HOURS. THIS
WILL SPONSOR CONTINUED LOW LEVEL CYCLOGENESIS ALONG THE LEE TROUGH
ACROSS SOUTHEASTERN COLORADO, EFFECTIVELY INCREASING THE SOUTHERLY
WINDS. NOCTURNAL TEMPERATURES WILL NOT MOVE MUCH OFF THE DIURNAL
TEMPERATURES WITH EARLY SUNDAY MORNING LOWS ONLY IN THE LOWER TO MID
50S EAST OF HIGHWAY 83.
SUNDAY: THE MAIN PRECIPITATION EVENT.
BY 12Z SUNDAY, THE 500MB LOW WILL CONTINUE TO DEEPEN WITH LATEST
MODEL CONSENSUS OF THE LOW CENTER SOMEWHERE ACROSS NORTHEASTERN NEW
MEXICO...AND A 700MB LOW ALONG THE EASTERN COLORADO-NEW MEXICO
BORDER. BY THIS TIME, WE SHOULD SEE A FAIRLY DECENT AREA OF SHOWERS
AND THUNDERSTORMS ALREADY UNDERWAY ACROSS THE TEXAS PANHANDLE. THIS
WILL BE THE BEGINNINGS OF A NORTHEASTWARD EXPANDING WARM CONVEYOR
BELT CONVECTIVE PRECIPITATION AXIS, WHICH WILL MOVE QUICKLY
NORTHEAST ACROSS SOUTHWEST KANSAS, ESPECIALLY DURING THE 12-18Z TIME
FRAME. IT IS INTERESTING THAT THE NAM12 IS ACTUALLY SLOWER THAN THE
ECMWF MODEL, WHICH IS OPPOSITE OF WHAT IS TYPICALLY SEEN FROM PAST
PERFORMANCE OF THE NAM REGARDING UPPER LOWS LIKE THIS. EITHER WAY,
BOTH THE NAM12 AND ECMWF SHOW SIGNIFICANT OCCLUSION OCCURRING DURING
THIS TIME FRAME WITH A DRY INTRUSION WORKING RAPIDLY NORTHWARD
AROUND THE EAST SIDE OF THE 700-500MB LOW CENTERS. IT IS LOOKING
MORE AND MORE LIKE A ONE-SHOT DEAL FOR DECENT ACCUMULATING RAINFALL -
- THE 12 TO 18Z TIME FRAME SUNDAY. THE NAM12 SHOWS 500-700 J/KG OF
MUCAPE WHICH REALLY COMES AS NO SURPRISE GIVEN A) THE 50-53F SURFACE
DEWPOINTS AND B) RAPIDLY COOLING MID LEVEL TEMPERATURES. THE WX
GRIDS WILL REFLECT THIS WITH SHOWERS AND ISOLATED THUNDERSTORMS WITH
THIS MAIN WARM CONVEYOR PRECIPITATION AREA. BY LATE IN THE
AFTERNOON, IT IS NOT UNREASONABLE TO THINK THAT SOME SUN MAY FILTER
IN BEHIND THE MAIN BAND OF MORNING/MIDDAY SHOWERS AND STORMS...AND
IF THAT WERE TO OCCUR, THE ATMOSPHERE WOULD RAPIDLY DESTABILIZE
ALLOWING ADDITIONAL SURFACE-BASED SHOWERS/ISOLATED THUNDERSTORMS TO
FORM WITHIN THE MID LEVEL DRY INTRUSION.
SUNDAY NIGHT-EARLY MONDAY: THE WRAP-AROUND AND CHANGE OVER TO WET
SNOW.
THE MID LEVEL CYCLONE WILL BE OCCLUDING AND FILLING FAST SUNDAY
NIGHT WITH THE 700MB LOW CENTERED SOMEWHERE ACROSS SOUTHWEST KANSAS.
WITH THE LOW CENTERED AT THIS LATITUDE, THE BEST AREA FOR WRAP-
AROUND COLD SECTOR DEFORMATION ZONE PRECIPITATION WILL BE ACROSS
NORTHWEST KANSAS AND ADJACENT EAST-CENTRAL/NORTHEAST COLORADO. THE
HIGHEST EVENING POPS WILL BE CONFINED TO FAR WEST-CENTRAL KANSAS
(SYRACUSE UP TO SCOTT CITY MAINLY). THE SOUTHERN PART OF THE WRAP-
AROUND PRECIPITATION SHIELD IN THE COLD SECTOR WILL MOST LIKELY BE
SNOW AS 850MB TEMPERATURES DROP TO -1 TO -3C, ESPECIALLY BY 06Z. BY
THIS TIME, HOWEVER, THE DEFORMATION ZONE IS EXPECTED TO WEAKEN AND
ANY WRAP-AROUND PRECIPITATION SHOULD BE RATHER LIGHT, AND CONFINED
MAINLY TO SYRACUSE-SCOTT CITY-WAKEENEY LINE. THE PROSPECT OF MODERATE
TO EVEN LIGHT ACCUMULATING SNOWFALL (TO CREATE ANY TRAVEL HAZARD)
FOR ANY PORTION OF THE DDC FORECAST AREA HAS DECREASED QUITE A BIT.
IN FACT, WE WON`T BE CARRYING ANY MORE THAN ABOUT A HALF INCH OF
SNOW ANYWHERE IN THE FORECAST AREA, AND THAT WILL ONLY BE UP IN
SCOTT-LANE-TREGO COUNTY.
EARLY WEEK: IN BETWEEN STORM SYSTEMS.
WE WILL SEE SOME SHORTWAVE RIDGING MONDAY NIGHT INTO TUESDAY IN THE
WAKE OF THE FIRST STORM. WE SHOULD ONLY RECEIVE A GLANCING SHOT OF
COOLER CANADIAN AIR, AND IT WILL NOT BE ARCTIC IN NATURE. MONDAY`S
HIGHS SHOULD BE IN THE LOWER TO MID 40S MOST EVERYWHERE WITH
NORTHWEST WINDS 15 TO 25 MPH OR SO (STRONGEST EARLY IN THE DAY).
EYES THEN TURN BACK OUT WEST AS ANOTHER DEEP TROUGH AND PACIFIC JET
DIVES TOWARD THE CALIFORNIA COAST. WE WILL REMAIN IN SHORTWAVE
RIDGING THROUGH WEDNESDAY AS THE NEXT STORM BEGINS TO TAKE SHAPE
ACROSS THE DESERT SOUTHWEST REGION WITH TEMPERATURES SEASONAL IN THE
LOWER 40S FOR HIGHS AND 20S FOR LOWS BOTH TUESDAY AND WEDNESDAY.
MID-LATE WEEK: THE NEXT STORM?
THERE IS A TREMENDOUS AMOUNT OF UNCERTAINTY REGARDING SENSIBLE
WEATHER CONCERNS DURING THE DEC 18-20 TIME FRAME. THE ECMWF
CONTINUES TO BE THE MOST AGGRESSIVE MODEL SUGGESTING A DECENT WINTER
PRECIPITATION EVENT ACROSS PORTIONS OF KANSAS LATE WEDNESDAY NIGHT
THROUGH THURSDAY EVENING. THE LEGACY GFS40 MODEL SHOWS A MUCH WEAKER
INITIAL WAVE AND THUS MUCH LESS DEVELOPMENT FOR PRECIPITATION DURING
THIS TIME FRAME. THE GFS40 FOCUSES MUCH OF ITS ENERGY ON THE SECOND
JET STREAK WHICH DIVES WAY DOWN INTO SOUTHWEST TEXAS. IN THE GRIDS,
WE WILL BE FOLLOWING THE SUPERBLEND GUIDANCE OF 20-30 POPS FOR
WEDNESDAY NIGHT, THURSDAY, THURSDAY NIGHT PERIODS FOR NOW WITH A
VAGUE "RAIN OR SNOW" AS THE WX TYPE RIGHT NOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 612 AM CST FRI DEC 12 2014
VERY POOR AVIATION WEATHER WILL CONTINUE WITH WIDESPREAD LIFR/IFR
EXPECTED FOR THE REMAINDER OF TODAY AND TONIGHT AS THE OVERALL
METEOROLOGICAL CONDITIONS REMAIN UNCHANGED UNTIL THE NEXT STORM
SYSTEM COMES SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 52 48 56 51 / 10 10 10 30
GCK 51 45 58 49 / 10 10 10 50
EHA 55 40 65 44 / 0 0 0 30
LBL 53 45 65 50 / 10 10 10 60
HYS 52 46 54 52 / 10 10 10 10
P28 53 48 57 54 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR KSZ030-
043>045-061>064-074>080-084>089.
&&
$$
SHORT TERM...SUGDEN
LONG TERM...UMSCHEID
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
435 AM CST FRI DEC 12 2014
...UPDATED LONG TERM SECTION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 1212 AM CST FRI DEC 12 2014
THIS MORNING:
SOME LOCATIONS LIKE KDDC HAVE BEEN GOING IN AND OUT OF FOG ADVISORY
CRITERIA, WHILE OTHER SITES OUT WEST STILL INDICATE DENSE FOG. IN ORDER
TO AVOID SPLITTING HAIRS, WILL CONTINUE THE ADVISORY AS IS AND EVEN
HAVE EXTENDED IN TIME AS THE FOG MAY LINGER LONGER THAN WHAT MODELS
ARE INDICATING. PUSHED THE EXPIRATION TIME OUT ANOTHER 2 HOURS. ABUNDANT
LOW LEVEL MOISTURE AND HRRR GUIDANCE STILL SUGGEST THAT A GOOD CHUNK
OF THE ADVISORY AREA WILL SEE DENSE FOG THROUGH LATE MORNING.
TODAY:
HAVE UNDERCUT GUIDANCE AGAIN WITH TEMPERATURES DUE TO FOG. HOWEVER,
THINK THAT LINGERING FOG WILL RESULT IN LOWER HIGHS LIKE WE SAW YESTERDAY.
UPSLOPE FOG SHOULD LINGER THEN LONGEST ACROSS THE WESTERN ZONES AND
HAVE GONE LOWER HERE. CALLING FOR 40S WEST TO 50S EAST. SOME
GUIDANCE IS ACTUALLY COOLER, WHILE OTHER GUIDANCE IS WARMER. SOME OF
THE MODELS MIGHT BE TOO AGGRESSIVE WITH FOG DECAY AND RESULTANT
WARMER SURFACE TEMPERATURES. BOTTOM LINE, ANOTHER TRICKY TEMPERATURE
DAY.
TONIGHT:
ANOTHER FOGGY NIGHT IS EXPECTED WITH SOME AREAS SEEING DENSE FOG AS
INDICATED PER FORECAST SOUNDINGS AND BUFKIT PLUMES. WILL KEEP FOG
IN THE GRIDS. THE NORTHERN AND EASTERN ZONES MAY SEE ENOUGH SATURATION
THICKNESS FOR PATCHY DRIZZLE, HOWEVER, LOOKS MORE OF FOG THAN DRIZZLE.
MINIMUMS WILL BE MILD AGAIN WITH THE FOG, HIGHER DEWPOINTS, AND CLOUD
COVER - 40S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 434 AM CST FRI DEC 12 2014
SATURDAY-SATURDAY NIGHT: AHEAD OF THE STORM.
AREAS OF FOG AND DRIZZLE WILL PERSIST THROUGH THE PERIOD ON
CONTINUED SOUTH-SOUTHEAST WINDS. LATE IN THE DAY, HOWEVER, SOME
SOUTHWESTERLY MOMENTUM WILL BEGIN TO IMPINGE ON FAR SOUTHWEST
KANSAS, ALLOWING THE STRATUS TO ERODE. AFTERNOON TEMPERATURES IN
AREAS LIKE ELKHART AND LIBERAL MAY EXCEED 60 DEGREES IF SOME SUN CAN
BE REALIZED AFTER NOON. OTHERWISE THE REST OF THE REGION WILL STAY
SOCKED IN WITH TEMPERATURES NEARLY STEADY IN THE MID 50S AS A
GENERAL RULE. THE MAJOR TROUGH OUT WEST WILL PUSH EAST INTO THE
ROCKIES BY SATURDAY NIGHT. THE ECMWF, GFS, AND CANADIAN GEM ALL
AGREE ON THE PLACEMENT OF THE MAJOR MID-LEVEL POTENTIAL VORTICITY
ANOMALY AT THE BASE OF THE TROUGH FROM CENTRAL ARIZONA EARLY IN THE
EVENING TO CENTRAL/SOUTHERN NEW MEXICO BY THE OVERNIGHT HOURS. THIS
WILL SPONSOR CONTINUED LOW LEVEL CYCLOGENESIS ALONG THE LEE TROUGH
ACROSS SOUTHEASTERN COLORADO, EFFECTIVELY INCREASING THE SOUTHERLY
WINDS. NOCTURNAL TEMPERATURES WILL NOT MOVE MUCH OFF THE DIURNAL
TEMPERATURES WITH EARLY SUNDAY MORNING LOWS ONLY IN THE LOWER TO MID
50S EAST OF HIGHWAY 83.
SUNDAY: THE MAIN PRECIPITATION EVENT.
BY 12Z SUNDAY, THE 500MB LOW WILL CONTINUE TO DEEPEN WITH LATEST
MODEL CONSENSUS OF THE LOW CENTER SOMEWHERE ACROSS NORTHEASTERN NEW
MEXICO...AND A 700MB LOW ALONG THE EASTERN COLORADO-NEW MEXICO
BORDER. BY THIS TIME, WE SHOULD SEE A FAIRLY DECENT AREA OF SHOWERS
AND THUNDERSTORMS ALREADY UNDERWAY ACROSS THE TEXAS PANHANDLE. THIS
WILL BE THE BEGINNINGS OF A NORTHEASTWARD EXPANDING WARM CONVEYOR
BELT CONVECTIVE PRECIPITATION AXIS, WHICH WILL MOVE QUICKLY
NORTHEAST ACROSS SOUTHWEST KANSAS, ESPECIALLY DURING THE 12-18Z TIME
FRAME. IT IS INTERESTING THAT THE NAM12 IS ACTUALLY SLOWER THAN THE
ECMWF MODEL, WHICH IS OPPOSITE OF WHAT IS TYPICALLY SEEN FROM PAST
PERFORMANCE OF THE NAM REGARDING UPPER LOWS LIKE THIS. EITHER WAY,
BOTH THE NAM12 AND ECMWF SHOW SIGNIFICANT OCCLUSION OCCURRING DURING
THIS TIME FRAME WITH A DRY INTRUSION WORKING RAPIDLY NORTHWARD
AROUND THE EAST SIDE OF THE 700-500MB LOW CENTERS. IT IS LOOKING
MORE AND MORE LIKE A ONE-SHOT DEAL FOR DECENT ACCUMULATING RAINFALL -
- THE 12 TO 18Z TIME FRAME SUNDAY. THE NAM12 SHOWS 500-700 J/KG OF
MUCAPE WHICH REALLY COMES AS NO SURPRISE GIVEN A) THE 50-53F SURFACE
DEWPOINTS AND B) RAPIDLY COOLING MID LEVEL TEMPERATURES. THE WX
GRIDS WILL REFLECT THIS WITH SHOWERS AND ISOLATED THUNDERSTORMS WITH
THIS MAIN WARM CONVEYOR PRECIPITATION AREA. BY LATE IN THE
AFTERNOON, IT IS NOT UNREASONABLE TO THINK THAT SOME SUN MAY FILTER
IN BEHIND THE MAIN BAND OF MORNING/MIDDAY SHOWERS AND STORMS...AND
IF THAT WERE TO OCCUR, THE ATMOSPHERE WOULD RAPIDLY DESTABILIZE
ALLOWING ADDITIONAL SURFACE-BASED SHOWERS/ISOLATED THUNDERSTORMS TO
FORM WITHIN THE MID LEVEL DRY INTRUSION.
SUNDAY NIGHT-EARLY MONDAY: THE WRAP-AROUND AND CHANGE OVER TO WET
SNOW.
THE MID LEVEL CYCLONE WILL BE OCCLUDING AND FILLING FAST SUNDAY
NIGHT WITH THE 700MB LOW CENTERED SOMEWHERE ACROSS SOUTHWEST KANSAS.
WITH THE LOW CENTERED AT THIS LATITUDE, THE BEST AREA FOR WRAP-
AROUND COLD SECTOR DEFORMATION ZONE PRECIPITATION WILL BE ACROSS
NORTHWEST KANSAS AND ADJACENT EAST-CENTRAL/NORTHEAST COLORADO. THE
HIGHEST EVENING POPS WILL BE CONFINED TO FAR WEST-CENTRAL KANSAS
(SYRACUSE UP TO SCOTT CITY MAINLY). THE SOUTHERN PART OF THE WRAP-
AROUND PRECIPITATION SHIELD IN THE COLD SECTOR WILL MOST LIKELY BE
SNOW AS 850MB TEMPERATURES DROP TO -1 TO -3C, ESPECIALLY BY 06Z. BY
THIS TIME, HOWEVER, THE DEFORMATION ZONE IS EXPECTED TO WEAKEN AND
ANY WRAP-AROUND PRECIPITATION SHOULD BE RATHER LIGHT, AND CONFINED
MAINLY TO SYRACUSE-SCOTT CITY-WAKEENEY LINE. THE PROSPECT OF MODERATE
TO EVEN LIGHT ACCUMULATING SNOWFALL (TO CREATE ANY TRAVEL HAZARD)
FOR ANY PORTION OF THE DDC FORECAST AREA HAS DECREASED QUITE A BIT.
IN FACT, WE WON`T BE CARRYING ANY MORE THAN ABOUT A HALF INCH OF
SNOW ANYWHERE IN THE FORECAST AREA, AND THAT WILL ONLY BE UP IN
SCOTT-LANE-TREGO COUNTY.
EARLY WEEK: IN BETWEEN STORM SYSTEMS.
WE WILL SEE SOME SHORTWAVE RIDGING MONDAY NIGHT INTO TUESDAY IN THE
WAKE OF THE FIRST STORM. WE SHOULD ONLY RECEIVE A GLANCING SHOT OF
COOLER CANADIAN AIR, AND IT WILL NOT BE ARCTIC IN NATURE. MONDAY`S
HIGHS SHOULD BE IN THE LOWER TO MID 40S MOST EVERYWHERE WITH
NORTHWEST WINDS 15 TO 25 MPH OR SO (STRONGEST EARLY IN THE DAY).
EYES THEN TURN BACK OUT WEST AS ANOTHER DEEP TROUGH AND PACIFIC JET
DIVES TOWARD THE CALIFORNIA COAST. WE WILL REMAIN IN SHORTWAVE
RIDGING THROUGH WEDNESDAY AS THE NEXT STORM BEGINS TO TAKE SHAPE
ACROSS THE DESERT SOUTHWEST REGION WITH TEMPERATURES SEASONAL IN THE
LOWER 40S FOR HIGHS AND 20S FOR LOWS BOTH TUESDAY AND WEDNESDAY.
MID-LATE WEEK: THE NEXT STORM?
THERE IS A TREMENDOUS AMOUNT OF UNCERTAINTY REGARDING SENSIBLE
WEATHER CONCERNS DURING THE DEC 18-20 TIME FRAME. THE ECMWF
CONTINUES TO BE THE MOST AGGRESSIVE MODEL SUGGESTING A DECENT WINTER
PRECIPITATION EVENT ACROSS PORTIONS OF KANSAS LATE WEDNESDAY NIGHT
THROUGH THURSDAY EVENING. THE LEGACY GFS40 MODEL SHOWS A MUCH WEAKER
INITIAL WAVE AND THUS MUCH LESS DEVELOPMENT FOR PRECIPITATION DURING
THIS TIME FRAME. THE GFS40 FOCUSES MUCH OF ITS ENERGY ON THE SECOND
JET STREAK WHICH DIVES WAY DOWN INTO SOUTHWEST TEXAS. IN THE GRIDS,
WE WILL BE FOLLOWING THE SUPERBLEND GUIDANCE OF 20-30 POPS FOR
WEDNESDAY NIGHT, THURSDAY, THURSDAY NIGHT PERIODS FOR NOW WITH A
VAGUE "RAIN OR SNOW" AS THE WX TYPE RIGHT NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1111 PM CST THU DEC 11 2014
POOR FLIGHT CONDITIONS THROUGH MUCH OF THE TAF PD, PARTICULARLY FOR
KGCK/KDDC. LIFR CONDITIONS MIGHT IMPROVE TO IFR THIS AFTERNOON, ALTHOUGH
THIS COULD BE TOO AGGRESSIVE AND THE GENERAL FLIGHT CATEGORY MIGHT JUST
CONTINUE LIFR THROUGH MUCH OF THE DAY WITHOUT IMPROVEMENT. ABUNDANT
MOISTURE WILL FAVOR FOG AND REDUCED VIS. DETERIORATING CONDITIONS LIKELY
AGAIN TONIGHT WITH LIFR PREVAILING AS FOG AND RESULTANT LOW VIS REDEVELOPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 52 48 56 51 / 10 10 10 30
GCK 51 45 58 49 / 10 10 10 50
EHA 55 40 65 44 / 0 0 0 30
LBL 53 45 65 50 / 10 10 10 60
HYS 52 46 54 52 / 10 10 10 10
P28 53 48 57 54 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST /11 AM MST/ TODAY FOR KSZ030-
043>045-061>064-074>080-084>089.
&&
$$
SHORT TERM...SUGDEN
LONG TERM...UMSCHEID
AVIATION...SUGDEN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
125 AM EST SAT DEC 13 2014
.UPDATE...
ISSUED AT 125 AM EST SAT DEC 13 2014
CLOUDS CONTINUE TO PROGRESS TO THE SOUTHEAST. SOME OF THE COOLER
VALLEYS HAVE ALREADY MADE IT INTO THE LOWER 20S IN PLACES WHERE
CLEARING HAS PERSISTED LONGER. TEMPERATURE REBOUNDS ASSOCIATED WITH
THE CLOUD BLANKET HAVE BEEN IMPRESSIVE UPSTREAM. HAVE ATTEMPTED TO
REFINE THE HOURLY TEMPERATURES AND DEW POINTS TO REFLECT THE LATEST
TRENDS IN OBSERVATIONS.
UPDATE ISSUED AT 1000 PM EST FRI DEC 12 2014
CLOUDS HAVE MADE IT INTO PORTIONS OF THE BLUEGRASS TONIGHT AND WILL
CONTINUE TO SLOWLY PROGRESS SE ACROSS THE CWA. MOST OF THE CWA IS
EXPECTED TO FILL IN WITH CLOUDS BY 11Z. TEMPERATURE FORECAST WILL BE
TRICKY AS SOME UPSTREAM OBS DID SEE A RISE IN TEMPS AS CLOUDS MOVED
OVER. DID OPT TO LEAN TOWARD THE HRRR AND RUC WHICH HAD BEST HANDLE
ON THE TEMP CHANGES. SO ADJUSTED MAINLY THE SKY AND TEMP GRIDS WITH
LATEST OBS/SAT/TRENDS.
UPDATE ISSUED AT 652 PM EST FRI DEC 12 2014
HIGH PRESSURE AND UPPER LEVEL RIDGE CONTINUE TO BUILD INTO EASTERN
KENTUCKY THIS EVENING. THE TRICKY PART OF THE FORECAST TONIGHT WILL
BE CLOUD COVER WE ARE TRACKING ON SATELLITE THIS EVENING ACROSS
WESTERN PORTIONS OF NORTH CENTRAL KY. THE TIMING WILL BE TRICKY AND
ONLY MESOSCALE GUIDANCE MODELS ARE REALLY ABLE TO HANDLE THIS
SITUATION AT THIS POINT. THESE CLOUDS ARE EXPECTED TO SLOWLY PROGRESS
SE INTO PORTIONS OF EASTERN KY OVERNIGHT INTO THE EARLY MORNING HOURS
ON SATURDAY. DID UPDATE SKY WITH LATEST SAT AND OBSERVATIONS. THIS
COULD ALSO HAVE A EFFECT ON TEMPS ACROSS THE REGION OVERNIGHT...HOWEVER
RIDGE/VALLEY DIFFERENCES ARE ALREADY SEEN ACROSS THE REGION WITH JKL
REPORTING 39 WHILE QKS IS 30 THIS HOUR. THIS IS EXPECTED TO CONTINUE
UNTIL CLOUD COVER SLOWLY WORKS INTO THE REGION. DID ADJUST TEMPS TO
CURRENT OBS.
&&
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 302 PM EST FRI DEC 12 2014
SURFACE HIGH PRESSURE OVER THE REGION IN COMBINATION WITH RIDGING
ALOFT BUILDING IN FROM THE WEST WILL BRING DRY WEATHER THROUGH THE
PERIOD. HOWEVER...FOR THOSE LOOKING FOR SUNSHINE AND MILD
WEATHER TYPICALLY SEEN WITH THIS PATTERN...IT WILL BE A WASTE OF A
STRONG UPPER LEVEL RIDGE. LOW LEVEL MOISTURE AND CLOUDS WERE
BLANKETING MOST OF THE MIDWEST TODAY NORTHWEST OF A LINE FROM KANSAS
CITY TO TOLEDO. WINDS JUST OFF THE SURFACE WILL BE LINED UP TO ADVECT
THIS WEATHER INTO THE JKL FORECAST AREA FOR THE WEEKEND. THE
NAM...WITH ITS HIGHER RESOLUTION...SEEMS TO BE HANDLING THIS SHALLOW
MOIST LAYER BETTER THAN THE GFS...AND THE NEW FORECAST WAS WEIGHTED
HEAVILY TOWARD THE CLOUDIER NAM. THAT BEING SAID...WE CAN EXPECT CLEAR
SKIES TO START THE NIGHT ONCE AGAIN. WITH CONDITIONS RESEMBLING THOSE
FROM YESTERDAY...RIDGE/VALLEY TEMPERATURE DIFFERENCES CAN BE EXPECTED
TO SET UP QUICKLY THIS EVENING. AS CLOUDS MOVE IN DURING THE NIGHT...
VALLEY TEMPERATURES SHOULD LEVEL OFF OR EVEN BEGIN TO RISE A
BIT OVERNIGHT...MEANING LESS TEMPERATURE VARIATION IS LIKELY BY THE
TIME SUNRISE ARRIVES. CLOUDS WILL RETARD OUR WARM-UP ON SATURDAY...
AND THE TEMPERATURE FORECAST LEANS TOWARD THE COOLER NAM METMOS MORE
SO THAN THE WARMER GFS MAVMOS. SOME EROSION OF CLOUDS MAY OCCUR ON
SATURDAY...MAINLY ON THE LEADING EDGE IN THE SOUTH. THIS COULD
PERMIT A BIT MORE WARMING IN THE SOUTHEAST CORNER OF THE STATE AROUND
MIDDLESBORO. TEMPERATURES ON SATURDAY NIGHT SHOULD BE MORE UNIFORM
DUE TO GREATER CLOUD COVER EXPECTED FOR THE BALANCE OF THE NIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 302 PM EST FRI DEC 12 2014
THE PERIOD WILL START WITH A MASSIVE RIDGE CENTERED OVER THE REGION
ON SUNDAY. UNFORTUNATELY...LOW LEVEL MOISTURE IS LIKELY TO REMAIN
TRAPPED BENEATH THE INVERSION...LEADING TO ANOTHER DAY OF CLOUDS. AS
THE RIDGE SLIDES TO THE EAST SUNDAY NIGHT INTO MONDAY...WE SHOULD
FINALLY SEE WINDS BECOME MORE SOUTHEASTERLY OR SOUTH...WITH CLOUDS
ON THE DECREASE WITH THE HOSTILE ENVIRONMENT DEVELOPING. MUCH MILDER
AIR WILL SURGE NORTHWARD MONDAY AND WITH SOME SUNSHINE...
TEMPERATURES SHOULD REACH WELL INTO THE 50S...SETTING UP A VERY
PLEASANT DAY. HOWEVER...OUR WINDOW FOR SUNSHINE WILL BE LIMITED...AS
CLOUDS WILL BE ON THE INCREASE THROUGH THE AFTERNOON AHEAD OF OUR
NEXT STORM SYSTEM. A SHORTWAVE TROUGH WILL PUSH FROM THE CENTRAL
PLAINS INTO THE GREAT LAKES LATE MONDAY INTO TUESDAY WITH A WEAKENING
WARM FRONT PUSHING ITS WAY ACROSS EASTERN KENTUCKY. WHILE MOISTURE
MAY BE LIMITED...ENOUGH LIFT IN THE MID LEVELS SHOULD SUPPORT AT
LEAST SOME LIGHT RAIN SHOWERS...WITH SOME LIGHT PRECIPITATION TOTALS
POSSIBLE. IT DOES NOT LOOK LIKE A WASH OUT BY ANY MEANS AS MOISTURE
IN THE LOW LEVELS IS VERY LIMITED EARLY ON. THE WARM FRONT WILL BE
FOLLOWED QUICKLY BY A COLD FRONT ON TUESDAY. BETTER MOISTURE WILL BE
PRESENT WITH THIS FRONT...SUPPORTING A GOOD CHANCE OF SHOWERS. UNLIKE
YESTERDAY...IT LOOKS LIKE MODELS ARE MORE PROGRESSIVE WITH SHOWERS
COMING TO AND END BY THE AFTERNOON AND EVENING. THIS WILL BE FOLLOWED
BY SHORTWAVE RIDGING WHICH WILL PROVIDE A TRANQUIL PERIOD OF WEATHER
FOR MIDWEEK. HOWEVER...MODELS ARE ALL OVER THE PLACE BY WEEKS
END...WITH VERY LOW CONFIDENCE. PLAN TO KEEP THE FORECAST DRY FOR NOW
WITH SUCH LOW CONFIDENCE. TEMPERATURES WILL REMAIN SEASONABLE THROUGH
NEXT WEEK...WITH NO REAL PUSHES OF COLDER AIR COMING ANYTIME SOON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 125 AM EST SAT DEC 13 2014
MVFR/IFR STRATOCU WILL GRADUALLY BUILD IN FROM THE NORTHWEST ACROSS
THE AREA THROUGH DAWN. ONCE THESE CLOUDS BUILD IN...THEY WILL LIKELY
PERSIST THROUGH THE REST OF THE PERIOD. THE DECK WILL LIKELY RAISE
SOMEWHAT DURING THE AFTERNOON HOURS...BEFORE LOWERING ONCE AGAIN INTO
SATURDAY EVENING. WINDS WILL REMAIN AT AROUND 5 KTS OR LESS THROUGH
THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...HAL
LONG TERM...KAS
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1229 AM EST Sat Dec 13 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1035 PM EST Fri Dec 12 2014
Quick update to the overnight period includes adjusting sky grids as
the stratus deck is marching slowly southeast across the forecast
area. It`s an all or nothing kind of cloud deck, and it`s not going
anywhere, so bumped sky cover up to 100 percent. These clouds are
going to greatly influence minimum temperatures as areas stuck in
clouds are holding in the mid 30s to near 40, while the Cumberland
region already has bottomed out in the upper 20s. The RAP seems to
be capturing the clouds and its impact on temperatures quite well,
so leaned toward that for lows.
.SHORT TERM (Now through Sunday)...
Issued at 340 PM EST Fri Dec 12 2014
Been watching cloud bank on satellite erode as it tries to push
east but this should only affect the far western areas initially.
Abundant low level moisture is seen on time height cross sections
for a majority of the period. So this is a tricky cloud forecast.
High pressure keeping stagnant airmass over the area and have an
air quality advisory out for the metro area.
High pressure will remain over the area through Sunday. In the
upper levels a ridge sits over the plains with troughs at both coasts.
by Sunday the ridge breaks down over the Ohio Valley as the system
currently off the east coast essentially remains there the the
trough over the west moves into the southern plains. The system to
our west is a slow moving one so we will not really see any
significant affects until Monday. Rain showers will spread across
the CWA during the day. Amounts will be light, but the clouds and
spotty precipitation will last into the extended period.
Clouds causing an issue with temperatures tonight as we might
bottom out early and increase later as the clouds increase again.
.LONG TERM (Sunday night through Friday)...
Issued at 340 PM EST Fri Dec 12 2014
The initial trough moving over the area early in the week is
expected to weaken, however another system is dropping out of
Canada during the middle of the week. The system from Canada is
not expected to get here, but it will slow the exit of the first system.
High pressure will be over the Ohio Valley by Wednesday and
gradually push east as another trough moves out of the
southwestern states. This next system should have more moisture
and possibly some thunder by next weekend. Kept it out of the
current package as there are questions about the speed of the
deeper moisture moving into our area.
Collaborated with surrounding offices to hold the rain chances off
until Friday. However, the main push of moisture looks to arrive
on Saturday.
&&
.AVIATION (06Z TAF Update)...
Issued at 1220 AM EST Sat Dec 13 2014
Plan on the stratus deck to persist at SDF/LEX/BWG through the
period as moisture remains trapped underneath a low-level inversion.
Ceilings will gradually lower through 12-15z this morning, bottoming
out between 800-1500 ft, lowest at LEX. For today, some indications
that cloud cover may become more broken or briefly scattered by late
morning into the afternoon hours, mainly at BWG. However, models
struggle with moisture this time of year, so kept forecast
pessimistic with broken/overcast clouds persisting. After 00z
tonight, higher confidence that more moisture arrives, and there
could be enough saturation for light drizzle and/or fog to develop,
especially at SDF/LEX. Also, probabilities for IFR ceilings are
greater but confidence was not high enough to include at this time.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........ZT
Short Term.....WFO PAH
Long Term......WFO PAH
Aviation.......ZT
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1041 PM EST Fri Dec 12 2014
...Forecast Update...
Issued at 1035 PM EST Fri Dec 12 2014
Quick update to the overnight period includes adjusting sky grids as
the stratus deck is marching slowly southeast across the forecast
area. It`s an all or nothing kind of cloud deck, and it`s not going
anywhere, so bumped sky cover up to 100 percent. These clouds are
going to greatly influence minimum temperatures as areas stuck in
clouds are holding in the mid 30s to near 40, while the Cumberland
region already has bottomed out in the upper 20s. The RAP seems to
be capturing the clouds and its impact on temperatures quite well,
so leaned toward that for lows.
.SHORT TERM (Now through Sunday)...
Issued at 340 PM EST Fri Dec 12 2014
Been watching cloud bank on satellite erode as it tries to push
east but this should only affect the far western areas initially.
Abundant low level moisture is seen on time height cross sections
for a majority of the period. So this is a tricky cloud forecast.
High pressure keeping stagnant airmass over the area and have an
air quality advisory out for the metro area.
High pressure will remain over the area through Sunday. In the
upper levels a ridge sits over the plains with troughs at both coasts.
by Sunday the ridge breaks down over the Ohio Valley as the system
currently off the east coast essentially remains there the the
trough over the west moves into the southern plains. The system to
our west is a slow moving one so we will not really see any
significant affects until Monday. Rain showers will spread across
the CWA during the day. Amounts will be light, but the clouds and
spotty precipitation will last into the extended period.
Clouds causing an issue with temperatures tonight as we might
bottom out early and increase later as the clouds increase again.
.LONG TERM (Sunday night through Friday)...
Issued at 340 PM EST Fri Dec 12 2014
The initial trough moving over the area early in the week is
expected to weaken, however another system is dropping out of
Canada during the middle of the week. The system from Canada is
not expected to get here, but it will slow the exit of the first system.
High pressure will be over the Ohio Valley by Wednesday and
gradually push east as another trough moves out of the
southwestern states. This next system should have more moisture
and possibly some thunder by next weekend. Kept it out of the
current package as there are questions about the speed of the
deeper moisture moving into our area.
Collaborated with surrounding offices to hold the rain chances off
until Friday. However, the main push of moisture looks to arrive
on Saturday.
&&
.AVIATION (00Z TAF Update)...
Issued at 610 PM EST Fri Dec 12 2014
Low clouds have pushed SE into SDF within the last hour or so, with
high-end MVFR ceilings. Cloud shield looks like it will stay north
of BWG this evening, but expect it to expand slowly into LEX just
before midnight. Low-level moisture will be increasingly trapped
below an inversion that will develop overnight, and ceilings will
most likely lower into fuel-alternate for a few hours early Saturday
morning. Also look for MVFR visibilities, and based on this morning
we can`t completely rule out IFR. However, expect the stratus to be
enough to keep visibilties from dropping too low.
This forecast is on board with the NAM depiction of a "goalpost"
sounding for much of the day on Saturday, with low clouds hanging in
all day under a steep inversion. At least expect ceilings to lift
above fuel-alternate late in the morning.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........ZT
Short Term.....WFO PAH
Long Term......WFO PAH
Aviation.......RAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1001 PM EST FRI DEC 12 2014
.UPDATE...
ISSUED AT 1000 PM EST FRI DEC 12 2014
CLOUDS HAVE MADE IT INTO PORTIONS OF THE BLUEGRASS TONIGHT AND WILL
CONTINUE TO SLOWLY PROGRESS SE ACROSS THE CWA. MOST OF THE CWA IS
EXPECTED TO FILL IN WITH CLOUDS BY 11Z. TEMPERATURE FORECAST WILL BE
TRICKY AS SOME UPSTREAM OBS DID SEE A RISE IN TEMPS AS CLOUDS MOVED
OVER. DID OPT TO LEAN TOWARD THE HRRR AND RUC WHICH HAD BEST HANDLE
ON THE TEMP CHANGES. SO ADJUSTED MAINLY THE SKY AND TEMP GRIDS WITH
LATEST OBS/SAT/TRENDS.
UPDATE ISSUED AT 652 PM EST FRI DEC 12 2014
HIGH PRESSURE AND UPPER LEVEL RIDGE CONTINUE TO BUILD INTO EASTERN
KENTUCKY THIS EVENING. THE TRICKY PART OF THE FORECAST TONIGHT WILL
BE CLOUD COVER WE ARE TRACKING ON SATELLITE THIS EVENING ACROSS
WESTERN PORTIONS OF NORTH CENTRAL KY. THE TIMING WILL BE TRICKY AND
ONLY MESOSCALE GUIDANCE MODELS ARE REALLY ABLE TO HANDLE THIS
SITUATION AT THIS POINT. THESE CLOUDS ARE EXPECTED TO SLOWLY PROGRESS
SE INTO PORTIONS OF EASTERN KY OVERNIGHT INTO THE EARLY MORNING HOURS
ON SATURDAY. DID UPDATE SKY WITH LATEST SAT AND OBSERVATIONS. THIS
COULD ALSO HAVE A EFFECT ON TEMPS ACROSS THE REGION OVERNIGHT...HOWEVER
RIDGE/VALLEY DIFFERENCES ARE ALREADY SEEN ACROSS THE REGION WITH JKL
REPORTING 39 WHILE QKS IS 30 THIS HOUR. THIS IS EXPECTED TO CONTINUE
UNTIL CLOUD COVER SLOWLY WORKS INTO THE REGION. DID ADJUST TEMPS TO
CURRENT OBS.
&&
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 302 PM EST FRI DEC 12 2014
SURFACE HIGH PRESSURE OVER THE REGION IN COMBINATION WITH RIDGING
ALOFT BUILDING IN FROM THE WEST WILL BRING DRY WEATHER THROUGH THE
PERIOD. HOWEVER...FOR THOSE LOOKING FOR SUNSHINE AND MILD
WEATHER TYPICALLY SEEN WITH THIS PATTERN...IT WILL BE A WASTE OF A
STRONG UPPER LEVEL RIDGE. LOW LEVEL MOISTURE AND CLOUDS WERE
BLANKETING MOST OF THE MIDWEST TODAY NORTHWEST OF A LINE FROM KANSAS
CITY TO TOLEDO. WINDS JUST OFF THE SURFACE WILL BE LINED UP TO ADVECT
THIS WEATHER INTO THE JKL FORECAST AREA FOR THE WEEKEND. THE
NAM...WITH ITS HIGHER RESOLUTION...SEEMS TO BE HANDLING THIS SHALLOW
MOIST LAYER BETTER THAN THE GFS...AND THE NEW FORECAST WAS WEIGHTED
HEAVILY TOWARD THE CLOUDIER NAM. THAT BEING SAID...WE CAN EXPECT CLEAR
SKIES TO START THE NIGHT ONCE AGAIN. WITH CONDITIONS RESEMBLING THOSE
FROM YESTERDAY...RIDGE/VALLEY TEMPERATURE DIFFERENCES CAN BE EXPECTED
TO SET UP QUICKLY THIS EVENING. AS CLOUDS MOVE IN DURING THE NIGHT...
VALLEY TEMPERATURES SHOULD LEVEL OFF OR EVEN BEGIN TO RISE A
BIT OVERNIGHT...MEANING LESS TEMPERATURE VARIATION IS LIKELY BY THE
TIME SUNRISE ARRIVES. CLOUDS WILL RETARD OUR WARM-UP ON SATURDAY...
AND THE TEMPERATURE FORECAST LEANS TOWARD THE COOLER NAM METMOS MORE
SO THAN THE WARMER GFS MAVMOS. SOME EROSION OF CLOUDS MAY OCCUR ON
SATURDAY...MAINLY ON THE LEADING EDGE IN THE SOUTH. THIS COULD
PERMIT A BIT MORE WARMING IN THE SOUTHEAST CORNER OF THE STATE AROUND
MIDDLESBORO. TEMPERATURES ON SATURDAY NIGHT SHOULD BE MORE UNIFORM
DUE TO GREATER CLOUD COVER EXPECTED FOR THE BALANCE OF THE NIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 302 PM EST FRI DEC 12 2014
THE PERIOD WILL START WITH A MASSIVE RIDGE CENTERED OVER THE REGION
ON SUNDAY. UNFORTUNATELY...LOW LEVEL MOISTURE IS LIKELY TO REMAIN
TRAPPED BENEATH THE INVERSION...LEADING TO ANOTHER DAY OF CLOUDS. AS
THE RIDGE SLIDES TO THE EAST SUNDAY NIGHT INTO MONDAY...WE SHOULD
FINALLY SEE WINDS BECOME MORE SOUTHEASTERLY OR SOUTH...WITH CLOUDS
ON THE DECREASE WITH THE HOSTILE ENVIRONMENT DEVELOPING. MUCH MILDER
AIR WILL SURGE NORTHWARD MONDAY AND WITH SOME SUNSHINE...
TEMPERATURES SHOULD REACH WELL INTO THE 50S...SETTING UP A VERY
PLEASANT DAY. HOWEVER...OUR WINDOW FOR SUNSHINE WILL BE LIMITED...AS
CLOUDS WILL BE ON THE INCREASE THROUGH THE AFTERNOON AHEAD OF OUR
NEXT STORM SYSTEM. A SHORTWAVE TROUGH WILL PUSH FROM THE CENTRAL
PLAINS INTO THE GREAT LAKES LATE MONDAY INTO TUESDAY WITH A WEAKENING
WARM FRONT PUSHING ITS WAY ACROSS EASTERN KENTUCKY. WHILE MOISTURE
MAY BE LIMITED...ENOUGH LIFT IN THE MID LEVELS SHOULD SUPPORT AT
LEAST SOME LIGHT RAIN SHOWERS...WITH SOME LIGHT PRECIPITATION TOTALS
POSSIBLE. IT DOES NOT LOOK LIKE A WASH OUT BY ANY MEANS AS MOISTURE
IN THE LOW LEVELS IS VERY LIMITED EARLY ON. THE WARM FRONT WILL BE
FOLLOWED QUICKLY BY A COLD FRONT ON TUESDAY. BETTER MOISTURE WILL BE
PRESENT WITH THIS FRONT...SUPPORTING A GOOD CHANCE OF SHOWERS. UNLIKE
YESTERDAY...IT LOOKS LIKE MODELS ARE MORE PROGRESSIVE WITH SHOWERS
COMING TO AND END BY THE AFTERNOON AND EVENING. THIS WILL BE FOLLOWED
BY SHORTWAVE RIDGING WHICH WILL PROVIDE A TRANQUIL PERIOD OF WEATHER
FOR MIDWEEK. HOWEVER...MODELS ARE ALL OVER THE PLACE BY WEEKS
END...WITH VERY LOW CONFIDENCE. PLAN TO KEEP THE FORECAST DRY FOR NOW
WITH SUCH LOW CONFIDENCE. TEMPERATURES WILL REMAIN SEASONABLE THROUGH
NEXT WEEK...WITH NO REAL PUSHES OF COLDER AIR COMING ANYTIME SOON.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 700 PM EST FRI DEC 12 2014
VFR CONDITIONS ARE EXPECTED MUCH OF THE EVENING. WE ARE TRACKING A AREA
OF CLOUD COVER...WITH MVFR/IFR CEILINGS SLOWLY PROGRESSING SE ACROSS
WESTERN PORTIONS OF NORTH CENTRAL KY THIS EVENING. THIS WILL SLOWLY
PROGRESS ACROSS TAF SITE OVERNIGHT TONIGHT. RIGHT NOW TIMING
CONTINUES TO BE TRICKY BUT DOES LOOK LIKE LEADING EDGE WILL MAKE IT
TO NEAR SYM/SME BY 05Z AND SLOWLY MOVE SE INTO SJS BY 07Z. THE
FORECAST IS TRICKY PAST THIS POINT...HOWEVER IT DOES LOOK LIKE WE
WILL KEEP THE MVFR/IFR CEILING THROUGH MUCH OF THE DAY. UNDER HIGH
PRESSURE WE ARE EXPECTING WINDS TO STAY LIGHT THROUGH THE TAF PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...HAL
LONG TERM...KAS
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
159 PM EST FRI DEC 12 2014
.UPDATE...
ISSUED AT 159 PM EST FRI DEC 12 2014
MADE ONLY MINOR CHANGES TO THE FORECAST FOR THIS AFTERNOON BASED ON
LATEST OBS.
UPDATE ISSUED AT 944 AM EST FRI DEC 12 2014
A PATCH OF LOW CLOUDS OVER NORTHERN KY IS HEADING TOWARD OUR NORTHERN
COUNTIES. THINK THAT WITH WARMING TODAY THE CLOUDS WILL ERODE. IT IS
A MATTER OF HOW QUICKLY THIS HAPPENS. HAVE UPDATED TO BRING PARTLY
CLOUDY SKIES INTO OUR FAR NW FOR A TIME AROUND MID DAY.
TEMPS ARE SLOWER TO WARM THIS MORNING THAN WAS FORECAST. HAVE CHANGED
THE TEMPORAL TEMPERATURE CURVE TO REFLECT THIS. HAVE NOT CHANGED THE
AFTERNOON HIGHS AT THIS POINT...WAITING TO SEE WHAT HAPPENS WITH
STRONGER WARMING ONCE THE SUN GETS HIGHER.
UPDATE ISSUED AT 700 AM EST FRI DEC 12 2014
TOUCHED UP THE T/TD GRIDS TO REFLECT CURRENT CONDITIONS AND TRENDS.
THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 335 AM EST FRI DEC 12 2014
07Z SFC ANALYSIS SHOWS CHILLY HIGH PRESSURE IN PLACE OVER THE OHIO
VALLEY. THIS HAS RESULTED IN CLEAR SKIES AND LIGHT WINDS SETTING THE
STAGE FOR A GOOD NIGHT OF RADIATIONAL COOLING. ACCORDINGLY...READINGS
EARLY THIS MORNING RANGE FROM AROUND 20 IN THE MOST SHELTERED VALLEYS
TO THE MID AND UPPER 20S ON THE RIDGES.
THE MODELS REMAIN IN GOOD AGREEMENT ALOFT DEPICTING THE SLOW RETREAT
OF THE DEEP AND BLOCKY NORTHEASTERN LOW. WHILE NORTH TO NORTHWEST
FLOW WILL HOLD IN PLACE OVER EASTERN KENTUCKY THROUGH SATURDAY...
THE PATTERN WILL BE STARVED OF MID LEVEL ENERGY AND HEIGHTS WILL
SLOWLY RISE THROUGH SATURDAY. GIVEN THE MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION NAM12 AND HRRR FOR WX DETAILS.
SENSIBLE WEATHER WILL FEATURE HIGH PRESSURE REMAINING OVER KENTUCKY
THROUGH THE SHORT TERM. FOR TODAY THIS WILL MEAN PLENTY OF SUNSHINE
AND SLIGHTLY WARMER CONDITIONS THAN YESTERDAY. IT WILL ALSO MEAN A
MOSTLY CLEAR START TO THE NIGHT AND DECENT RADIATIONAL COOLING THIS
EVENING. HOWEVER...THE NAM DOES SUGGEST THAT A THICK LAYER OF LOW
STRATUS DEVELOPS AFTER MIDNIGHT AND SETTLES OVER EASTERN KENTUCKY...
PERHAPS HOLDING ON THROUGH THE DAY SATURDAY. SO...DESPITE THE HIGH
PRESSURE THIS MOISTURE WILL LIKELY RUIN WHAT SHOULD BE A SUNNY DAY
AND ALSO KEEP SATURDAY AFTERNOON TEMPERATURES FROM WARMING MUCH MORE
THAN THEY WILL THIS AFTERNOON. HAVE TAKEN THIS INTO ACCOUNT AND MADE
SOME SUCH PESSIMISTIC ADJUSTMENTS TO THE CURRENT FORECAST. IN FACT...
CANNOT COMPLETELY RULE OUT POCKETS OF DRIZZLE FALLING OUT OF THESE
LOW CLOUDS LATE TONIGHT AND INTO THE DAY SATURDAY.
AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND
GRIDS WITH SOME TERRAIN BASED ADJUSTMENTS MADE TONIGHT...MAINLY
EARLY. AS FOR POPS AND WX...KEPT THEM LOW AND NON-EXISTENT FRIDAY
GIVEN THE HIGH PRESSURE REGIME NOW IN PLACE...AND IN LINE WITH SINGLE
DIGIT MOS GUIDANCE FOR SATURDAY AS THE LOW LEVEL MOISTURE SURGES INTO
THE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 315 AM EST FRI DEC 12 2014
THE EXTENDED FORECAST WILL EXHIBIT A PATTERN OF CHANGE AS THE
NOREASTER FINALLY STARTS ITS SHIFT EASTWARD...AND ALLOWS FOR A
CHANGING AND LESS SETTLING UPPER LEVEL PATTERN TO TAKE SHAPE ACROSS
THE OHIO RIVER VALLEY.
WHILE THE NOREASTER IS BREWING JUST OFF THE NEW ENGLAND
COAST...ANOTHER LARGE TROUGH WILL BEGIN IMPOSING ON THE WESTERN
CONUS...WITH TWO DISTINCT SHORT WAVES STRENGTHENING INTO CLOSED LOWS
DEVELOPING BETWEEN 0 AND 12Z SUNDAY. AS THEY SHIFT EASTWARD...THIS
WILL PUSH THE AXIS OF THE RIDGE OF HIGH PRESSURE ACROSS THE OHIO
RIVER VALLEY SUNDAY AND KEEP CALM CONDITIONS IN PLACE. THE ONLY
CAVEAT IS THE POTENTIAL FOR SOME POPS/MOISTURE TO ROUND THE NORTHERN
EXTENT OF THE TROUGH /NAMELY POINTS TO OUR NORTH/. THIS WILL LIKELY
KEEP LOW CLOUDS ACROSS MUCH OF THE REGION THROUGH THE DAY
SUNDAY...KEPT IN PLACE BY A STRONG LOW LEVEL INVERSION. THIS
MOISTURE WILL FINALLY DEPART BY MONDAY...AS HIGH PRESSURE SHIFTS
JUST TO OUR EAST...AND WE START TO FEEL THE INFLUENCE OF THE
INCOMING UPPER LEVEL TROUGH AND FIRST CLOSED LOW.
BY 12Z MONDAY...THIS LOW WILL BE MOVING INTO THE MISSISSIPPI RIVER
VALLEY AND WILL BEGIN MERGING WITH THE SECONDARY CLOSED LOW TO IT/S
NE. AS HEIGHTS FALL ACROSS THE AREA...STRONG SOUTHERLY FLOW WILL
ENSUE ON THE FRONT SIDE OF THE SHORTWAVE/CLOSED LOW. THIS WILL BE
ENOUGH TO BOOST TEMPS UP INTO THE LOW 50S ACROSS A GOOD PORTION OF
THE CWA...AS WELL AS PULL IN MOISTURE OFF OF THE GULF COAST. WHILE
FORECAST SOUNDINGS HAVE US CLEARING OUT IN THE LOW LEVELS MONDAY
WITHOUT THE INFLUENCE OF THE HIGH PRESSURE INDUCED INVERSION...IN
THE UPPER LEVELS CLOUDS WILL BEGIN THICKENING AGAIN. THIS LAST MODEL
RUN...THE GFS AND ECMWF HAVE FINALLY COME INTO A BETTER AGREEMENT
FOR THE START AND END TIMES OF THIS PRECIP BAND. BOTH SHOW THE
PRECIP MOVING INTO THE CWA BETWEEN 0Z AND 6Z TUESDAY.
ORIGINALLY...THE GFS CUT PRECIP POTENTIAL OFF BY 0Z
WEDNESDAY...WHILE THE ECMWF HELD ONTO UPSLOPE PRECIP SOME 12 HOURS
LONGER. WITH THIS LATEST MODEL RUN...IT SEEMS AS THOUGH THE ECMWF IS
NOW STEERING INTO BETTER AGREEMENT WITH THE GFS...WHICH IS A BIT
SURPRISING CONSIDERING THAT THE UPSLOPE FLOW IS STILL IN PLACE. AS
SUCH...KEPT WITH THE MODEL BLEND /INCLUDING THE PREVIOUS RUN OF THE
ECMWF/...IN WHICH SOME SLIGHT CHANCES OF RAIN MAY LINGER OVER THE SE
HIGH TERRAIN TIL AROUND 12Z WEDNESDAY.
ONCE THIS SYSTEM MOVES THROUGH THE REGION...IT APPEARS AS THOUGH
ANOTHER...MORE MILD...RIDGE OF HIGH PRESSURE TAKES HOLD ACROSS KY.
HOWEVER...THERE IS A LARGE AMOUNT OF DISAGREEMENT IN THE MODELS BY
THIS POINT...SO WOULDN/T BE SURPRISED IF THURSDAY AND FRIDAY/S
FORECAST WAS ALTERED AS WE MOVE THROUGH THE NEXT FEW DAYS. AS IT IS
NOW...A SHORTWAVE WILL LIKELY IMPACT THE REGION BY FRIDAY...BRINGING
THE NEXT CHANCE OF PRECIP TO THE REGION. REGARDLESS...THE LACK OF
LARGE VARIATIONS ALOFT...AS WELL AS CONTINUED LOW LEVEL MOISTURE AND
CLOUD COVER...WILL LEAD TO FAIRLY UNIFORM TEMPS FROM WEDNESDAY
THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 159 PM EST FRI DEC 12 2014
VFR CONDITIONS WILL LAST INTO THE NIGHT. A LAYER OF STRATUS WILL MOVE
IN FROM THE NW DURING THE NIGHT AND BRING LOW MVFR AND POCKETS OF
IFR CEILINGS. TENTATIVE TIMING HAS IT ARRIVING IN THE VICINITY OF
MOUNT STERLING AND MOREHEAD AROUND 05Z...AND REACHING THE VA BORDER
AROUND 10Z. HOWEVER...THERE IS A FAIR DEGREE OF UNCERTAINTY
REGARDING TIMING. LOW CEILINGS WILL PERSIST INTO THE DAY
SATURDAY...BUT MAY SHOW SOME RETREAT IN THE SOUTHEAST CORNER OF THE
STATE AROUND MIDDLESBORO. WINDS WILL BE LIGHT THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
944 AM EST FRI DEC 12 2014
.UPDATE...
ISSUED AT 944 AM EST FRI DEC 12 2014
A PATCH OF LOW CLOUDS OVER NORTHERN KY IS HEADING TOWARD OUR NORTHERN
COUNTIES. THINK THAT WITH WARMING TODAY THE CLOUDS WILL ERODE. IT IS
A MATTER OF HOW QUICKLY THIS HAPPENS. HAVE UPDATED TO BRING PARTLY
CLOUDY SKIES INTO OUR FAR NW FOR A TIME AROUND MID DAY.
TEMPS ARE SLOWER TO WARM THIS MORNING THAN WAS FORECAST. HAVE CHANGED
THE TEMPORAL TEMPERATURE CURVE TO REFLECT THIS. HAVE NOT CHANGED THE
AFTERNOON HIGHS AT THIS POINT...WAITING TO SEE WHAT HAPPENS WITH
STRONGER WARMING ONCE THE SUN GETS HIGHER.
UPDATE ISSUED AT 700 AM EST FRI DEC 12 2014
TOUCHED UP THE T/TD GRIDS TO REFLECT CURRENT CONDITIONS AND TRENDS.
THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 335 AM EST FRI DEC 12 2014
07Z SFC ANALYSIS SHOWS CHILLY HIGH PRESSURE IN PLACE OVER THE OHIO
VALLEY. THIS HAS RESULTED IN CLEAR SKIES AND LIGHT WINDS SETTING THE
STAGE FOR A GOOD NIGHT OF RADIATIONAL COOLING. ACCORDINGLY...READINGS
EARLY THIS MORNING RANGE FROM AROUND 20 IN THE MOST SHELTERED VALLEYS
TO THE MID AND UPPER 20S ON THE RIDGES.
THE MODELS REMAIN IN GOOD AGREEMENT ALOFT DEPICTING THE SLOW RETREAT
OF THE DEEP AND BLOCKY NORTHEASTERN LOW. WHILE NORTH TO NORTHWEST
FLOW WILL HOLD IN PLACE OVER EASTERN KENTUCKY THROUGH SATURDAY...
THE PATTERN WILL BE STARVED OF MID LEVEL ENERGY AND HEIGHTS WILL
SLOWLY RISE THROUGH SATURDAY. GIVEN THE MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION NAM12 AND HRRR FOR WX DETAILS.
SENSIBLE WEATHER WILL FEATURE HIGH PRESSURE REMAINING OVER KENTUCKY
THROUGH THE SHORT TERM. FOR TODAY THIS WILL MEAN PLENTY OF SUNSHINE
AND SLIGHTLY WARMER CONDITIONS THAN YESTERDAY. IT WILL ALSO MEAN A
MOSTLY CLEAR START TO THE NIGHT AND DECENT RADIATIONAL COOLING THIS
EVENING. HOWEVER...THE NAM DOES SUGGEST THAT A THICK LAYER OF LOW
STRATUS DEVELOPS AFTER MIDNIGHT AND SETTLES OVER EASTERN KENTUCKY...
PERHAPS HOLDING ON THROUGH THE DAY SATURDAY. SO...DESPITE THE HIGH
PRESSURE THIS MOISTURE WILL LIKELY RUIN WHAT SHOULD BE A SUNNY DAY
AND ALSO KEEP SATURDAY AFTERNOON TEMPERATURES FROM WARMING MUCH MORE
THAN THEY WILL THIS AFTERNOON. HAVE TAKEN THIS INTO ACCOUNT AND MADE
SOME SUCH PESSIMISTIC ADJUSTMENTS TO THE CURRENT FORECAST. IN FACT...
CANNOT COMPLETELY RULE OUT POCKETS OF DRIZZLE FALLING OUT OF THESE
LOW CLOUDS LATE TONIGHT AND INTO THE DAY SATURDAY.
AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND
GRIDS WITH SOME TERRAIN BASED ADJUSTMENTS MADE TONIGHT...MAINLY
EARLY. AS FOR POPS AND WX...KEPT THEM LOW AND NON-EXISTENT FRIDAY
GIVEN THE HIGH PRESSURE REGIME NOW IN PLACE...AND IN LINE WITH SINGLE
DIGIT MOS GUIDANCE FOR SATURDAY AS THE LOW LEVEL MOISTURE SURGES INTO
THE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 315 AM EST FRI DEC 12 2014
THE EXTENDED FORECAST WILL EXHIBIT A PATTERN OF CHANGE AS THE
NOREASTER FINALLY STARTS ITS SHIFT EASTWARD...AND ALLOWS FOR A
CHANGING AND LESS SETTLING UPPER LEVEL PATTERN TO TAKE SHAPE ACROSS
THE OHIO RIVER VALLEY.
WHILE THE NOREASTER IS BREWING JUST OFF THE NEW ENGLAND
COAST...ANOTHER LARGE TROUGH WILL BEGIN IMPOSING ON THE WESTERN
CONUS...WITH TWO DISTINCT SHORT WAVES STRENGTHENING INTO CLOSED LOWS
DEVELOPING BETWEEN 0 AND 12Z SUNDAY. AS THEY SHIFT EASTWARD...THIS
WILL PUSH THE AXIS OF THE RIDGE OF HIGH PRESSURE ACROSS THE OHIO
RIVER VALLEY SUNDAY AND KEEP CALM CONDITIONS IN PLACE. THE ONLY
CAVEAT IS THE POTENTIAL FOR SOME POPS/MOISTURE TO ROUND THE NORTHERN
EXTENT OF THE TROUGH /NAMELY POINTS TO OUR NORTH/. THIS WILL LIKELY
KEEP LOW CLOUDS ACROSS MUCH OF THE REGION THROUGH THE DAY
SUNDAY...KEPT IN PLACE BY A STRONG LOW LEVEL INVERSION. THIS
MOISTURE WILL FINALLY DEPART BY MONDAY...AS HIGH PRESSURE SHIFTS
JUST TO OUR EAST...AND WE START TO FEEL THE INFLUENCE OF THE
INCOMING UPPER LEVEL TROUGH AND FIRST CLOSED LOW.
BY 12Z MONDAY...THIS LOW WILL BE MOVING INTO THE MISSISSIPPI RIVER
VALLEY AND WILL BEGIN MERGING WITH THE SECONDARY CLOSED LOW TO IT/S
NE. AS HEIGHTS FALL ACROSS THE AREA...STRONG SOUTHERLY FLOW WILL
ENSUE ON THE FRONT SIDE OF THE SHORTWAVE/CLOSED LOW. THIS WILL BE
ENOUGH TO BOOST TEMPS UP INTO THE LOW 50S ACROSS A GOOD PORTION OF
THE CWA...AS WELL AS PULL IN MOISTURE OFF OF THE GULF COAST. WHILE
FORECAST SOUNDINGS HAVE US CLEARING OUT IN THE LOW LEVELS MONDAY
WITHOUT THE INFLUENCE OF THE HIGH PRESSURE INDUCED INVERSION...IN
THE UPPER LEVELS CLOUDS WILL BEGIN THICKENING AGAIN. THIS LAST MODEL
RUN...THE GFS AND ECMWF HAVE FINALLY COME INTO A BETTER AGREEMENT
FOR THE START AND END TIMES OF THIS PRECIP BAND. BOTH SHOW THE
PRECIP MOVING INTO THE CWA BETWEEN 0Z AND 6Z TUESDAY.
ORIGINALLY...THE GFS CUT PRECIP POTENTIAL OFF BY 0Z
WEDNESDAY...WHILE THE ECMWF HELD ONTO UPSLOPE PRECIP SOME 12 HOURS
LONGER. WITH THIS LATEST MODEL RUN...IT SEEMS AS THOUGH THE ECMWF IS
NOW STEERING INTO BETTER AGREEMENT WITH THE GFS...WHICH IS A BIT
SURPRISING CONSIDERING THAT THE UPSLOPE FLOW IS STILL IN PLACE. AS
SUCH...KEPT WITH THE MODEL BLEND /INCLUDING THE PREVIOUS RUN OF THE
ECMWF/...IN WHICH SOME SLIGHT CHANCES OF RAIN MAY LINGER OVER THE SE
HIGH TERRAIN TIL AROUND 12Z WEDNESDAY.
ONCE THIS SYSTEM MOVES THROUGH THE REGION...IT APPEARS AS THOUGH
ANOTHER...MORE MILD...RIDGE OF HIGH PRESSURE TAKES HOLD ACROSS KY.
HOWEVER...THERE IS A LARGE AMOUNT OF DISAGREEMENT IN THE MODELS BY
THIS POINT...SO WOULDN/T BE SURPRISED IF THURSDAY AND FRIDAY/S
FORECAST WAS ALTERED AS WE MOVE THROUGH THE NEXT FEW DAYS. AS IT IS
NOW...A SHORTWAVE WILL LIKELY IMPACT THE REGION BY FRIDAY...BRINGING
THE NEXT CHANCE OF PRECIP TO THE REGION. REGARDLESS...THE LACK OF
LARGE VARIATIONS ALOFT...AS WELL AS CONTINUED LOW LEVEL MOISTURE AND
CLOUD COVER...WILL LEAD TO FAIRLY UNIFORM TEMPS FROM WEDNESDAY
THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 715 AM EST FRI DEC 12 2014
VFR CONDITIONS WILL BE THE RULE THROUGH THIS EVENING BEFORE A DECK OF
MVFR STRATUS IS EXPECTED TO DEVELOP AND AFFECT THE TAF SITES FROM
NORTHWEST TO SOUTHEAST LATE TONIGHT. WINDS DURING THE PERIOD WILL BE
LIGHT...GENERALLY FROM THE WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
715 AM EST FRI DEC 12 2014
.UPDATE...
ISSUED AT 700 AM EST FRI DEC 12 2014
TOUCHED UP THE T/TD GRIDS TO REFLECT CURRENT CONDITIONS AND TRENDS.
THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 335 AM EST FRI DEC 12 2014
07Z SFC ANALYSIS SHOWS CHILLY HIGH PRESSURE IN PLACE OVER THE OHIO
VALLEY. THIS HAS RESULTED IN CLEAR SKIES AND LIGHT WINDS SETTING THE
STAGE FOR A GOOD NIGHT OF RADIATIONAL COOLING. ACCORDINGLY...READINGS
EARLY THIS MORNING RANGE FROM AROUND 20 IN THE MOST SHELTERED VALLEYS
TO THE MID AND UPPER 20S ON THE RIDGES.
THE MODELS REMAIN IN GOOD AGREEMENT ALOFT DEPICTING THE SLOW RETREAT
OF THE DEEP AND BLOCKY NORTHEASTERN LOW. WHILE NORTH TO NORTHWEST
FLOW WILL HOLD IN PLACE OVER EASTERN KENTUCKY THROUGH SATURDAY...
THE PATTERN WILL BE STARVED OF MID LEVEL ENERGY AND HEIGHTS WILL
SLOWLY RISE THROUGH SATURDAY. GIVEN THE MODEL AGREEMENT HAVE FAVORED
THE HIGHER RESOLUTION NAM12 AND HRRR FOR WX DETAILS.
SENSIBLE WEATHER WILL FEATURE HIGH PRESSURE REMAINING OVER KENTUCKY
THROUGH THE SHORT TERM. FOR TODAY THIS WILL MEAN PLENTY OF SUNSHINE
AND SLIGHTLY WARMER CONDITIONS THAN YESTERDAY. IT WILL ALSO MEAN A
MOSTLY CLEAR START TO THE NIGHT AND DECENT RADIATIONAL COOLING THIS
EVENING. HOWEVER...THE NAM DOES SUGGEST THAT A THICK LAYER OF LOW
STRATUS DEVELOPS AFTER MIDNIGHT AND SETTLES OVER EASTERN KENTUCKY...
PERHAPS HOLDING ON THROUGH THE DAY SATURDAY. SO...DESPITE THE HIGH
PRESSURE THIS MOISTURE WILL LIKELY RUIN WHAT SHOULD BE A SUNNY DAY
AND ALSO KEEP SATURDAY AFTERNOON TEMPERATURES FROM WARMING MUCH MORE
THAN THEY WILL THIS AFTERNOON. HAVE TAKEN THIS INTO ACCOUNT AND MADE
SOME SUCH PESSIMISTIC ADJUSTMENTS TO THE CURRENT FORECAST. IN FACT...
CANNOT COMPLETELY RULE OUT POCKETS OF DRIZZLE FALLING OUT OF THESE
LOW CLOUDS LATE TONIGHT AND INTO THE DAY SATURDAY.
AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR THE T/TD/WIND
GRIDS WITH SOME TERRAIN BASED ADJUSTMENTS MADE TONIGHT...MAINLY
EARLY. AS FOR POPS AND WX...KEPT THEM LOW AND NON-EXISTENT FRIDAY
GIVEN THE HIGH PRESSURE REGIME NOW IN PLACE...AND IN LINE WITH SINGLE
DIGIT MOS GUIDANCE FOR SATURDAY AS THE LOW LEVEL MOISTURE SURGES INTO
THE AREA.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 315 AM EST FRI DEC 12 2014
THE EXTENDED FORECAST WILL EXHIBIT A PATTERN OF CHANGE AS THE
NOREASTER FINALLY STARTS ITS SHIFT EASTWARD...AND ALLOWS FOR A
CHANGING AND LESS SETTLING UPPER LEVEL PATTERN TO TAKE SHAPE ACROSS
THE OHIO RIVER VALLEY.
WHILE THE NOREASTER IS BREWING JUST OFF THE NEW ENGLAND
COAST...ANOTHER LARGE TROUGH WILL BEGIN IMPOSING ON THE WESTERN
CONUS...WITH TWO DISTINCT SHORT WAVES STRENGTHENING INTO CLOSED LOWS
DEVELOPING BETWEEN 0 AND 12Z SUNDAY. AS THEY SHIFT EASTWARD...THIS
WILL PUSH THE AXIS OF THE RIDGE OF HIGH PRESSURE ACROSS THE OHIO
RIVER VALLEY SUNDAY AND KEEP CALM CONDITIONS IN PLACE. THE ONLY
CAVEAT IS THE POTENTIAL FOR SOME POPS/MOISTURE TO ROUND THE NORTHERN
EXTENT OF THE TROUGH /NAMELY POINTS TO OUR NORTH/. THIS WILL LIKELY
KEEP LOW CLOUDS ACROSS MUCH OF THE REGION THROUGH THE DAY
SUNDAY...KEPT IN PLACE BY A STRONG LOW LEVEL INVERSION. THIS
MOISTURE WILL FINALLY DEPART BY MONDAY...AS HIGH PRESSURE SHIFTS
JUST TO OUR EAST...AND WE START TO FEEL THE INFLUENCE OF THE
INCOMING UPPER LEVEL TROUGH AND FIRST CLOSED LOW.
BY 12Z MONDAY...THIS LOW WILL BE MOVING INTO THE MISSISSIPPI RIVER
VALLEY AND WILL BEGIN MERGING WITH THE SECONDARY CLOSED LOW TO IT/S
NE. AS HEIGHTS FALL ACROSS THE AREA...STRONG SOUTHERLY FLOW WILL
ENSUE ON THE FRONT SIDE OF THE SHORTWAVE/CLOSED LOW. THIS WILL BE
ENOUGH TO BOOST TEMPS UP INTO THE LOW 50S ACROSS A GOOD PORTION OF
THE CWA...AS WELL AS PULL IN MOISTURE OFF OF THE GULF COAST. WHILE
FORECAST SOUNDINGS HAVE US CLEARING OUT IN THE LOW LEVELS MONDAY
WITHOUT THE INFLUENCE OF THE HIGH PRESSURE INDUCED INVERSION...IN
THE UPPER LEVELS CLOUDS WILL BEGIN THICKENING AGAIN. THIS LAST MODEL
RUN...THE GFS AND ECWMF HAVE FINALLY COME INTO A BETTER AGREEMENT
FOR THE START AND END TIMES OF THIS PRECIP BAND. BOTH SHOW THE
PRECIP MOVING INTO THE CWA BETWEEN 0Z AND 6Z TUESDAY.
ORIGINALLY...THE GFS CUT PRECIP POTENTIAL OFF BY 0Z
WEDNESDAY...WHILE THE ECMWF HELD ONTO UPSLOPE PRECIP SOME 12 HOURS
LONGER. WITH THIS LATEST MODEL RUN...IT SEEMS AS THOUGH THE ECMWF IS
NOW STEERING INTO BETTER AGREEMENT WITH THE GFS...WHICH IS A BIT
SURPRISING CONSIDERING THAT THE UPSLOPE FLOW IS STILL IN PLACE. AS
SUCH...KEPT WITH THE MODEL BLEND /INCLUDING THE PREVIOUS RUN OF THE
ECMWF/...IN WHICH SOME SLIGHT CHANCES OF RAIN MAY LINGER OVER THE SE
HIGH TERRAIN TIL AROUND 12Z WEDNESDAY.
ONCE THIS SYSTEM MOVES THROUGH THE REGION...IT APPEARS AS THOUGH
ANOTHER...MORE MILD...RIDGE OF HIGH PRESSURE TAKES HOLD ACROSS KY.
HOWEVER...THERE IS A LARGE AMOUNT OF DISAGREEMENT IN THE MODELS BY
THIS POINT...SO WOULDN/T BE SURPRISED IF THURSDAY AND FRIDAY/S
FORECAST WAS ALTERED AS WE MOVE THROUGH THE NEXT FEW DAYS. AS IT IS
NOW...A SHORTWAVE WILL LIKELY IMPACT THE REGION BY FRIDAY...BRINGING
THE NEXT CHANCE OF PRECIP TO THE REGION. REGARDLESS...THE LACK OF
LARGE VARIATIONS ALOFT...AS WELL AS CONTINUED LOW LEVEL MOISTURE AND
CLOUD COVER...WILL LEAD TO FAIRLY UNIFORM TEMPS FROM WEDNESDAY
THROUGH FRIDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 715 AM EST FRI DEC 12 2014
VFR CONDITIONS WILL BE THE RULE THROUGH THIS EVENING BEFORE A DECK OF
MVFR STRATUS IS EXPECTED TO DEVELOP AND AFFECT THE TAF SITES FROM
NORTHWEST TO SOUTHEAST LATE TONIGHT. WINDS DURING THE PERIOD WILL BE
LIGHT...GENERALLY FROM THE WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...JMW
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1245 AM EST SAT DEC 13 2014
.SYNOPSIS...
CLOUDS AND PATCHY DRIZZLE WILL PLAGUE MUCH OF THE REGION THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
CURRENT IR SATELLITE IMAGERY CONTINUING TO SHOW A SHARP CONTRAST
BETWEEN AREAS UNDER LOW STRATUS AND THOSE UNDER CLEAR SKIES. HEADING
INTO THE OVERNIGHT...LOW STRATUS IS EXPECTED TO ENCROACH THE CLEAR
AREAS FROM THE NORTH AND WEST. NOT MUCH HAS CHANGED IN THE TIMING
OF THE CLOUDS ENTERING OUR WRN PERIPHERY...AROUND 04-05Z. THIS
BANK OF STRATUS IS BASED BELOW 1KFT AND WILL GRADUALLY ENGULF THE
BALANCE OF THE CWA THROUGH THE PRE-DAWN HOURS.
UPDATED TEMPS TO BETTER REFLECT CURRENT TRENDS WITH SOME COLDER
LOCATIONS SOUTH UNDER CLEAR SKIES. LATEST HRRR REPRESENTS THE CURRENT
SITUATION WELL...AND NICELY DEPICTS A FEW DEGREE REBOUND WITH THE
ARRIVAL OF THE WRN CLOUD BANK. BLENDED THIS GUIDANCE WITH THE
PREVIOUS FORECAST THROUGH ABOUT 15Z SAT.
HIGHER DEWPOINTS CURRENT AND FORECAST WILL INCREASE THE NEAR SFC
RH COMPARED TO THE LAST FEW NIGHTS...GIVING BIRTH TO THE POTENTIAL
OF FREEZING DRIZZLE OVERNIGHT. ALREADY BEGINNING TO SEE SOME
UPSTREAM OBS REPORTING FZFG/FZDZ INTO NERN INDIANA AND SRN
MICHIGAN. NOW BEGINNING TO SEE 0-2F DEGREE DEWPOINT SPREADS ALONG
THE NORTHERN 1/3 OF THE CWA...AND ALTHOUGH NO ASOS OBS HAVE
REPORTED IT...VIS RESTRICTIONS HAVE HINTED AT THE PRESENCE OF
PATCHY FREEZING DRIZZLE. AS A RESULT...HAVE ISSUED AN SPS FOR THIS AREA THROUGH
05Z AND EXPANDED THE MENTION OF PATCHY FREEZING DRIZZLE OVER THE
REMAINDER OF THE CWA. OVERALL CONFIDENCE IN COVERAGE IS STILL
RELATIVELY LOW. WILL CONTINUE TO HOLD OFF ON ANY ADVISORY ATTM.
TAX
&&
.SHORT TERM /TONIGHT THROUGH MONDAY/...
THE HIGH AMPLITUDE RIDGE AXIS...ANALYZED OVR THE HIGH PLNS AREA
TDA...IS FORECAST TO BLD EWD THROUGH THE WEEKEND IN RESPONSE TO
ADVNG TROF OFF THE PACIFIC. A DROUGHT OF MEASURABLE PCPN WL THUS
ENSUE...BUT MSTR IS FORECAST TO RMN TRAPPED UNDR THE SBSDNC
INVERSION...POSSIBLY INTO LATE SUNDAY...WHEN WIND AT THE TOP OF
THE SHALLOW BNDRY LYR IS DECISIVELY FORECAST TO BACK TO THE SW AND
END COLD REINFORCEMENT AT THE TOP OF THAT LYR. WL THUS CONT A PESSIMISTIC
CLD FORECAST WITH A SUB AVG TEMP FORECAST AS WELL AS THE POTENTIAL
FOR MORE WIDESPREAD FREEZING DRIZZLE ON SATURDAY NGT.
BY MONDAY...MDL WORLD INDICATES THE AFOREMENTIONED W COAST TROF
AXIS DVLPG TWD THE WRN LAKES AND LOWER OHIO REGIONS. WARM ADVCTN
IN ADVN OF THAT FEATURE SHOULD FINALLY MODERATE TEMPS...WITH PCPN
CHCS HOLDING OFF UNTIL THE APCH OF THAT SYSTEMS ATTENDANT CDFNT ON TUESDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE MID LVL LOW PRES CNTR OF THE ORIGINAL UPR TROF IS CURRENTLY
FORECAST ACRS THE GREAT LAKES ON TUESDAY...SUFFICIENTLY W TO
ENSURE ANY ASSOCIATED PCPN WL FALL AS RAIN OVR THE UPR OH REGION.
A LATE WEEK SHRTWV MAY STILL SPAWN SOME PCPN CHCS...SO NO MAJOR
ALTERATIONS WERE THUS NEEDED FOR THE LONG TERM PD.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
STRATUS DECK CONTINUES TO ADVANCE SOUTH AND EAST. EXPECT IT TO
OVERSPREAD THE ENTIRE REGION OVER THE NEXT FEW HOURS WITH IFR/LIFR
CIG AND VIS IN BR. FREEZING DRIZZLE STILL A GOOD POSSIBILITY AT
TIMES AND KEPT IN AS A TEMPO FOR MANY TERMINALS. SHOULD BE ABLE TO
MIX THE BOUNDARY LAYER ENOUGH TO ALLOW CONDITIONS TO IMPROVE TO
MVFR BY LATE MORNING AND THROUGH THE AFTERNOON. CIGS WILL BEGIN TO
DROP AGAIN DURING SATURDAY EVENING. CANNOT RULE OUT IFR RETURNING
BY 06Z SUNDAY. CL
OUTLOOK.../SUNDAY THROUGH WEDNESDAY/...
EXPECT LOW CLOUDS TO LINGER THROUGH SUNDAY AND INTO MONDAY...WITH
VFR CONDITIONS PERHAPS RETURNING BY MONDAY NIGHT IN DEVELOPING SW
FLOW. A COLD FRONT MAY BRING RENEWED RESTRICTIONS ON TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
939 PM EST FRI DEC 12 2014
.SYNOPSIS...
CLOUDS AND PATCHY DRIZZLE WILL PLAGUE MUCH OF THE REGION THIS
WEEKEND.
&&
.NEAR TERM /THROUGH SATURDAY/...
CURRENT IR SATELLITE IMAGERY CONTINUING TO SHOW A SHARP CONTRAST
BETWEEN AREAS UNDER LOW STRATUS AND THOSE UNDER CLEAR SKIES. HEADING
INTO THE OVERNIGHT...LOW STRATUS IS EXPECTED TO ENCROACH THE CLEAR
AREAS FROM THE NORTH AND WEST. NOT MUCH HAS CHANGED IN THE TIMING
OF THE CLOUDS ENTERING OUR WRN PERIPHERY...AROUND 04-05Z. THIS
BANK OF STRATUS IS BASED BELOW 1KFT AND WILL GRADUALLY ENGULF THE
BALANCE OF THE CWA THROUGH THE PRE-DAWN HOURS.
UPDATED TEMPS TO BETTER REFLECT CURRENT TRENDS WITH SOME COLDER
LOCATIONS SOUTH UNDER CLEAR SKIES. LATEST HRRR REPRESENTS THE CURRENT
SITUATION WELL...AND NICELY DEPICTS A FEW DEGREE REBOUND WITH THE
ARRIVAL OF THE WRN CLOUD BANK. BLENDED THIS GUIDANCE WITH THE
PREVIOUS FORECAST THROUGH ABOUT 15Z SAT.
HIGHER DEWPOINTS CURRENT AND FORECAST WILL INCREASE THE NEAR SFC
RH COMPARED TO THE LAST FEW NIGHTS...GIVING BIRTH TO THE POTENTIAL
OF FREEZING DRIZZLE OVERNIGHT. ALREADY BEGINNING TO SEE SOME
UPSTREAM OBS REPORTING FZFG/FZDZ INTO NERN INDIANA AND SRN
MICHIGAN. NOW BEGINNING TO SEE 0-2F DEGREE DEWPOINT SPREADS ALONG
THE NORTHERN 1/3 OF THE CWA...AND ALTHOUGH NO ASOS OBS HAVE
REPORTED IT...VIS RESTRICTIONS HAVE HINTED AT THE PRESENCE OF
PATCHY FREEZING DRIZZLE. AS A RESULT...HAVE ISSUED AN SPS FOR THIS AREA THROUGH
05Z AND EXPANDED THE MENTION OF PATCHY FREEZING DRIZZLE OVER THE
REMAINDER OF THE CWA. OVERALL CONFIDENCE IN COVERAGE IS STILL
RELATIVELY LOW. WILL CONTINUE TO HOLD OFF ON ANY ADVISORY ATTM.
TAX
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
THE HIGH AMPLITUDE RIDGE AXIS...ANALYZED OVR THE HIGH PLNS AREA
TDA...IS FORECAST TO BLD EWD THROUGH THE WEEKEND IN RESPONSE TO
ADVNG TROF OFF THE PACIFIC. A DROUGHT OF MEASURABLE PCPN WL THUS
ENSUE...BUT MSTR IS FORECAST TO RMN TRAPPED UNDR THE SBSDNC
INVERSION...POSSIBLY INTO LATE SUNDAY...WHEN WIND AT THE TOP OF
THE SHALLOW BNDRY LYR IS DECISIVELY FORECAST TO BACK TO THE SW AND
END COLD REINFORCEMENT AT THE TOP OF THAT LYR. WL THUS CONT A PESSIMISTIC
CLD FORECAST WITH A SUB AVG TEMP FORECAST AS WELL AS THE POTENTIAL
FOR MORE WIDESPREAD FREEZING DRIZZLE ON SATURDAY NGT.
BY MONDAY...MDL WORLD INDICATES THE AFOREMENTIONED W COAST TROF
AXIS DVLPG TWD THE WRN LAKES AND LOWER OHIO REGIONS. WARM ADVCTN
IN ADVN OF THAT FEATURE SHOULD FINALLY MODERATE TEMPS...WITH PCPN
CHCS HOLDING OFF UNTIL THE APCH OF THAT SYSTEMS ATTENDANT CDFNT ON TUESDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE MID LVL LOW PRES CNTR OF THE ORIGINAL UPR TROF IS CURRENTLY
FORECAST ACRS THE GREAT LAKES ON TUESDAY...SUFFICIENTLY W TO
ENSURE ANY ASSOCIATED PCPN WL FALL AS RAIN OVR THE UPR OH REGION.
A LATE WEEK SHRTWV MAY STILL SPAWN SOME PCPN CHCS...SO NO MAJOR
ALTERATIONS WERE THUS NEEDED FOR THE LONG TERM PD.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
WHERE STRATUS HAS ERODED THIS EVENING...A SHORT-LIVED PERIOD OF
VFR CONDITIONS WILL LIKELY BE ABRUPTLY ENDED AS A WALL OF LIFR
STRATUS ADVANCES EASTWARD ACROSS OHIO THIS EVENING. THIS SHOULD
COVER ALL SITES OVERNIGHT...WITH MODEL SOUNDINGS SUGGESTING A
CHANCE OF FREEZING DRIZZLE OR SNOW GRAINS POSSIBLE AT VIRTUALLY
ALL SITES. SOME BOUNDARY LAYER MIXING MAY BE ENOUGH TO LIFT THE
STRATUS A TAD BY SATURDAY AFTERNOON AND END THE THREAT OF
DRIZZLE...HOWEVER ONLY SLIGHT IMPROVEMENT OVER IFR SEEMS LIKELY
WITH A CONTINUATION OF STRATUS. FRIES
OUTLOOK.../SATURDAY THROUGH TUESDAY/...
THE STRATUS...STRATOCU RESTRICTION POTENTIAL IS EXPECTED TO LINGER
INTO SUNDAY WITH GENL IMPROVEMENT INDICATED BY MONDAY AS OVRALL
BNDRY LYR FLOW BACKS TO THE SW IN ADVN OF A MIDWRN SHRTWV.
HOWEVER...RESTRICTION POTENTIAL IS AGAIN ANTICIPATED ON TUESDAY
WITH THAT SYSTEMS CDFNT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
247 PM EST FRI DEC 12 2014
.SYNOPSIS...
CLOUDS AND PATCHY DRIZZLE WILL PLAGUE MUCH OF THE REGION THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE LATE AFTN UPDATE FEATURED ADJUSTMENTS TO CLD COVER AND TEMPS
AS CLD DECK HAS RETREATED NWD ON THE STRENGTH OF BACKED FLOW IN
ADVN OF A WEAK SHRTWV. USED HRRR MSTR PROGS TO REFILL THE CLDS LTR
THIS EVE WITH PASSAGE OF THE DISTURBANCE.
PREVIOUS...
BLDG HIGH PRES ALOFT WL ENSURE A LACK OF MEASURABLE PCPN FOR THE
UPR OH REGION...BUT MSTR TRAPPED UNDR A LOW INVERSION LVL WL CONT
TO SUPPLY STRATUS AND PATCHY DRIZZLE THROUGH TNGT. A MENTION OF
FREEZING DRIZZLE WAS INCLUDED FOR THE HIGHER ELEVATIONS TNGT...BUT
DO ANTICIPATE TRAVEL ISSUES AT MOMENT...HENCE WL ABSTAIN FM AN
ADVISORY HEADLINE AS AN EVE SPECIAL WEATHER STATEMENT SHOULD
SUFFICE SHOULD PATCHY DVLPMNT OCCUR.
GIVEN THE WIDESPREAD CLD COVER PROJECTED IN THE NR TERM PD...HAVE
TWEAKED THE HIGH TO LOW SPREAD CLOSER WITH PERSISTENCE AND
INCOMING GUIDANCE TRENDS.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
THE HIGH AMPLITUDE RIDGE AXIS...ANALYZED OVR THE HIGH PLNS AREA
TDA...IS FORECAST TO BLD EWD THROUGH THE WEEKEND IN RESPONSE TO
ADVNG TROF OFF THE PACIFIC. A DROUGHT OF MEASURABLE PCPN WL THUS
ENSUE...BUT MSTR IS FORECAST TO RMN TRAPPED UNDR THE SBSDNC
INVERSION...POSSIBLY INTO LATE SUNDAY...WHEN WIND AT THE TOP OF
THE SHALLOW BNDRY LYR IS DECISIVELY FORECAST TO BACK TO THE SW AND
END COLD REINFORCEMENT AT THE TOP OF THAT LYR. WL THUS CONT A PESSIMISTIC
CLD FORECAST WITH A SUB AVG TEMP FORECAST AS WELL AS THE POTENTIAL
FOR MORE WIDESPREAD FREEZING DRIZZLE ON SATURDAY NGT.
BY MONDAY...MDL WORLD INDICATES THE AFOREMENTIONED W COAST TROF
AXIS DVLPG TWD THE WRN LAKES AND LOWER OHIO REGIONS. WARM ADVCTN
IN ADVN OF THAT FEATURE SHOULD FINALLY MODERATE TEMPS...WITH PCPN
CHCS HOLDING OFF UNTIL THE APCH OF THAT SYSTEMS ATTENDANT CDFNT ON TUESDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE MID LVL LOW PRES CNTR OF THE ORIGINAL UPR TROF IS CURRENTLY
FORECAST ACRS THE GREAT LAKES ON TUESDAY...SUFFICIENTLY W TO
ENSURE ANY ASSOCIATED PCPN WL FALL AS RAIN OVR THE UPR OH REGION.
A LATE WEEK SHRTWV MAY STILL SPAWN SOME PCPN CHCS...SO NO MAJOR
ALTERATIONS WERE THUS NEEDED FOR THE LONG TERM PD.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
MVFR STRATOCU/AREAS OF IFR STRATUS WL CONT TO PLAGUE UPR OH
TERMINALS THROUGH SATURDAY AS LLVL MSTR RMNS TRAPPED UNDR A SBSDNC
INVERSION. CONFIDENCE IS SUFFICIENT TDA TO INCLUDE IFR DEGRADATION
TNGT AND EARLY SATURDAY.
OUTLOOK.../SATURDAY THROUGH TUESDAY/...
THE STRATUS...STRATOCU RESTRICTION POTENTIAL IS EXPECTED TO LINGER
INTO SUNDAY WITH GENL IMPROVEMENT INDICATED BY MONDAY AS OVRALL
BNDRY LYR FLOW BACKS TO THE SW IN ADVN OF A MIDWRN SHRTWV.
HOWEVER...RESTRICTION POTENTIAL IS AGAIN ANTICIPATED ON TUESDAY
WITH THAT SYSTEMS CDFNT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
15
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
501 AM EST SUN DEC 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EST SUN DEC 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SPLIT FLOW PATTERN ACROSS
NORTH AMERICA WITH AN UNSESONABLY STRONG RIDGE FROM THE MS
VALLEY INTHE WRN GREAT LAKES DOWNSTREAM FROM A TROUIGH ACROSS THE
ROCKIES. AT THE SFC..SRLY WINDS WERE INCREASING FROM THE CENTRAL
PLAINS TOWARD THE UPPER MS VALLEY AHEAD OF A TROUGH FROM CENTRAL
SOUTH DAKOTA INTO WRN NEBRASKA. THE SRLY FLOW AND LOW LEVEL MOISTURE
ADVECTION HAS PUSHED DEWPOINTS TO NEAR 40F FROM CENTRAL MN AND NW WI
TO WRN UPPER MI AND INTO THE MID 30S THROUGH CNTRL UPPER MI. A
PERSISTENT LOW STRATUS DECK HAS HELPED KEEP FOG FROM BECOMING AS
DENSE OVER UPPER MI COMPARED TO LOCATIONS OVER WI.
THERE REMAINS ONLY WEAK IF ANY FORCING FOR UPWARD MOTION OVER UPPER
MI TODAY AS THE AREA REMAINS NEAR THE MID/UPPER LEVEL RIDGE AXIS.
NEVERTHELESS...THE POTENTIAL FOR DRIZZLE SPREADING ACROSS THE AREA
REMAINS AS SOME WEAK UPWARD MOTION IS EXPECTED ABOVE THE THICKENING
LOW LEVEL MOISTURE AHEAD OF THE TROUGH SLIDING INTO THE UPPER MS
VALLEY. DRIZZLE CHANCES WILL INCREASE TOWARD EVENING AS AN AREA OF
290K ISENTROPIC ASCENT IS FORECAST TO MOVE THROUGH UPPER MI...PER
NAM/GFS. IN ADDITION...MELTING SNOW WILL ADD ADDITIONAL MOISTURE TO
SUPPORT DEVELOPMENT OF AREAS OF DENSE FOG. HOWEVER...DIURNAL WARMING
SHOULD BE JUST ENOUGH TO REDUCE THE RISK FOR MORE WIDESPREAD DENSE
FOG. TONIGHT...DENSE FOG WILL BE A BETTER POSSIBILITY WITH DIURNAL
COOING AS DEWPOINTS INTO THE UPPER 30S PREVAIL ACROSS THE AREA. THE
THE POTENTIAL FOR ACCUMULATING PCPN WILL INCREASE LATE TONIGHT OVER
THE WEST WITH DEEPER MOISTURE ARRIVING AHEAD OF THE SFC TROUGH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 257 AM EST SUN DEC 14 2014
AFTER A WARM START TO THE LONG TERM PERIOD...A RETURN TO MORE
NORMAL MID DECEMBER TEMPERATURES IS IN STORE FOR TUESDAY AND
CONTINUING THROUGH MUCH OF THE REST OF THE WORK WEEK. ON MONDAY
MORNING...THE ANOMALOUS UPPER RIDGE WILL BE LOCATED OVER THE LOWER
GREAT LAKES REGION AND QUICKLY SHIFTING EAST INTO THE NEW ENGLAND
STATES. MEANWHILE...TWO SHORTWAVES WILL BE NEARING THE AREA AND
WILL BE THE FOCUS FOR THE FIRST HALF OF THE WORK WEEK. FIRST...THE
SOUTHERN STREAM SHORTWAVE WILL BE LOCATED IN EASTERN KANSAS AT 12Z
MONDAY AND WILL BE DRIVING THE 1001MB SURFACE LOW LOCATED IN NEARLY
THE SAME LOCATION. FROM THAT SURFACE LOW...A 1006MB TROUGH WILL
EXTEND NORTHEAST THROUGH EASTERN MINNESOTA AND INTO WESTERN LAKE
SUPERIOR. AT THAT SAME TIME...A SECONDARY SHORTWAVE WILL BE DIVING
SOUTHEAST THROUGH MANITOBA. AS THE SHORTWAVE AND SURFACE LOW LIFT
NORTHEAST TOWARDS CHICAGO BY MONDAY EVENING...THE ELONGATED TROUGH
WILL SLOWLY SHIFT EAST OUT OF WESTERN LAKE SUPERIOR AND INTO THE
WESTERN U.P. AHEAD OF THE TROUGH...THE WARM/MOIST LOW LEVEL AIR
WILL CONTINUE TO PRODUCE LOW CLOUDS...DRIZZLE...AND FOG (ALTHOUGH
THERE COULD BE PERIODS OF LIGHT RAIN SHOWERS UNDER THE WEAK WARM AIR
ADVECTION AND DEEPER MOISTURE NEAR THE TROUGH AXIS). SURFACE
TEMPERATURES ON MONDAY WILL LIKELY BE FAIRLY STEADY IN THE UPPER
30S AND LOWER 40S.
HEADING INTO MONDAY NIGHT...THE SURFACE LOW AND SOUTHERN STREAM
SHORTWAVE WILL BE SLIDING INTO LOWER MICHIGAN...WHILE THE NORTHERN
STREAM SHORTWAVE BECOMES CLOSE ENOUGH TO START INTERACTING WITH
SOUTHERN SHORTWAVE. THIS WILL HELP SHIFT THE SURFACE AND LOW LEVEL
TROUGH EAST ACROSS UPPER MICHIGAN THROUGH THE NIGHT...AND BRING
COLDER LOW LEVEL AIR INTO THE AREA. OVERALL...MODELS ARE FAIRLY
CONSISTENT IN THE IDEA OF THAT COLD AIR SWITCHING THE RAIN TO SNOW
FROM NORTHWEST TO SOUTHEAST MONDAY NIGHT INTO TUESDAY MORNING.
FIRST...HAPPENING IN THE KIWD/KCMX AREA BETWEEN 02-06Z TUESDAY AND
THEN KSAW/KIMT AROUND 09Z AND AREAS OVER THE SOUTHEAST BY 18Z
TUESDAY. WITH THOSE SHORTWAVE STARTING TO INTERACT MONDAY
NIGHT...AIDING THE TIGHTENING LOW-MID LEVEL FGEN...WOULD EXPECT A
PERIOD OF MODERATE PRECIPITATION OVER WESTERN LAKE SUPERIOR AND
WESTERN UPPER MICHIGAN ON MONDAY NIGHT. SNOWFALL AMOUNTS FOR THAT
PERIOD WILL LIKELY DEPEND ON THE TIMING OF THE CHANGE OVER...BUT
WITH THE GOING TIMING WOULD EXPECT TO SEE 1-3IN FROM HERMAN TO
WATERSMEET AND WEST BY DAYBREAK TUESDAY. FARTHER EAST...THAT
DELAYED ARRIVAL OF THE COLDER AIR WILL KEEP MORE OF THE
PRECIPITATION AS RAIN BEFORE SWITCHING TO SNOW. WHEN FACTORING IN
ADDITIONAL SNOW FOR TUESDAY...MAY NEED AN ADVISORY FOR THOSE AREAS
OVER THE WEST AND WILL CONTINUE TO INCLUDE MODERATE SNOWFALL MENTION
IN THE HWO.
HEADING INTO TUESDAY...THE SURFACE LOW AND SHORTWAVE WILL SHIFT EAST
THROUGH THE LOWER GREAT LAKES AND REDUCE THE DIRECT INTERACTION OF
IT WITH THE SECONDARY SHORTWAVE NOW SLIDING SOUTH THROUGH WESTERN
LAKE SUPERIOR AND THE MINNESOTA ARROWHEAD. WHILE THIS WILL LIKELY
WEAKEN THE SYNOPTICLY FORCED PRECIPITATION...THE COLDER AIR SURGING
OVER LAKE SUPERIOR ON TUESDAY (850MB TEMPS FALLING TO AROUND -14C
OVER THE WESTERN LAKE) SHOULD LEAD TO A TRANSITION TO LAKE
ENHANCED/EFFECT SNOW OVER THE WEST INITIALLY AND THEN SHIFTING EAST
ACROSS THE REST OF THE AREA BY EVENING. CONFIDENCE DOES BEGIN TO
WAVER SOME ON TUESDAY AND CONTINUE INTO WEDNESDAY AS THE TWO
SHORTWAVE INTERACT WITH EACH OTHER OVER THE GREAT LAKES REGION.
THIS LEADS TO DIFFERENCES IN THE EXACT MODEL SOLUTIONS...BUT THE
GENERAL IDEA IS FOR THE SURFACE LOW TO CONTINUE EAST...LEAVING A
TROUGH STRETCHED WEST-NORTHWEST ACROSS LAKE SUPERIOR ON TUESDAY
AFTERNOON/EVENING UNTIL THE TRAILING SHORTWAVE CAN SLIDE IT SOUTH
WEDNESDAY. THE 00Z GFS DOES DIFFER FROM THIS IDEA AND LINGERS THE
TROUGH OVER THE UPPER GREAT LAKES UNTIL THURSDAY MORNING...WHILE THE
00Z ECMWF CAME IN A LITTLE SLOWER BUT NOT AS DELAYED AS THE GFS.
WILL FOLLOW THE GENERAL CONSENSUS AT THIS POINT AND HAVE IT MOVING
SOUTH ON TUESDAY NIGHT INTO WEDNESDAY. THEREFORE...SHOULD SEE A
PERIOD OF NORTHERLY FLOW LAKE EFFECT SPREADING ACROSS THE AREA ON
TUESDAY INTO TUESDAY NIGHT FROM WEST TO EAST AND CONTINUING INTO
WEDNESDAY. UNTIL THE COLDER AIR CAN MOVE INTO THE AREA LATER
TUESDAY AFTERNOON AND NIGHT...EXPECT THE LAKE ENHANCED PRECIPITATION
INTENSITY TO BE LIMITED TO THE WEST HALF AND WHERE IT SNOWS THE
RATIOS WILL BE ON THE LOW END (AROUND 12-1). AS THAT COLDER AIR
MOVES IN...THE CLOUD LAYER WILL NOSE INTO THE DGZ AND INCREASE THE
RATIOS...BUT THE AREA WILL ALSO START TO SEE THE AFFECT OF THE HIGH
BUILDING SOUTH INTO SOUTHERN CANADA AND THE NORTHERN PLAINS. THAT
WILL STRENGTHEN THE INVERSION AROUND 5KFT AND HELP LIMIT THE
STRENGTH OF THE LAKE EFFECT PRECIPITATION. WHILE MUCH OF THE
FORECAST DEPENDS ON THE TIMING OF THAT SURFACE TROUGH DROPPING
ACROSS THE AREA...STILL WOULD EXPECT MANY LOCATIONS IN THE NORTHERLY
WIND SNOW BELTS TO SEE A COUPLE TO SEVERAL INCHES OF LAKE
ENHANCED/EFFECT SNOW TUESDAY AFTERNOON INTO WEDNESDAY. WILL
ALSO HIGHLIGHT THIS POTENTIAL IN THE HWO AS SOME AREAS MAY SEE
ADVISORY SNOWFALL.
BEHIND THE SURFACE TROUGH...EXPECT THE LAKE EFFECT TO DIMINISH
WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING AS THE AREA OF HIGH
PRESSURE BEGINS TO SLIDE SOUTHEAST INTO THE UPPER GREAT LAKES
REGION. WARMING TEMPERATURES ALOFT WILL ARRIVE WITH UPPER RIDGE AND
LEAD TO A QUIET END TO THE WORK WEEK AND LIKELY INTO NEXT WEEKEND.
MODELS ARE FAIRLY CONSISTENT ON THE HIGH REMAINING OVER THE UPPER
GREAT LAKES REGION THROUGH THIS PERIOD. AS FOR TEMPERATURES...EXPECT
HIGHS IN THE MID-UPPER 20S FOR THE END OF THE WORK WEEK THAT MAY TRY
TO NOSE INTO THE LOWER 30S FOR NEXT WEEKEND (WHICH WOULD BE AROUND 5
DEGREES ABOVE NORMAL FOR THAT TIME OF DECEMBER).
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 842 PM EST SAT DEC 13 2014
IN THE PRESENCE OF DIURNAL COOLING...SLOWLY DIMINISHING SW WINDS AND
THE ARRIVAL OF MOISTER LLVL AIR OVER MELTING SN PACK...EXPECT
CONDITIONS AT CMX AND SAW TO DETERIORATE TO LIFR AND THEN VLIFR
OVERNGT. DOWNSLOPE WIND COMPONENT AT IWD WL LIKELY WL LIKELY LIMIT
THE WORST CONDITIONS TO LIFR THERE. THERE WL BE ONLY A SLOW RECOVERY
TO IFR CONDITIONS ON SUN AFTN WITH CONTINUED INFLUX OF MORE LLVL
MSTR AND LO SUN ANGLE HINDERING A MORE SGNFT IMPROVEMENT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 341 PM EST SAT DEC 13 2014
WARMER AIR WILL KEEP THE MENTION OF FREEZING SPRAY OUT OF THE FCST
FOR THE TIME BEING. THE CONCERN IN THE NEAR TERM WILL BE OFF AND ON
FOG TONIGHT THROUGH TUESDAY OVER MAINLY S PORTIONS OF LAKE
SUPERIOR.
A RIDGE ACROSS THE UPPER GREAT LAKES WILL SLOWLY SHIFT TO
THE LOWER GREAT LAKES SUNDAY INTO MONDAY. LOOK FOR AN ELONGATED AREA
OF LOW PRESSURE ACROSS THE PLAINS STATES SUNDAY MORNING TO PUSH
ACROSS LAKE SUPERIOR LATE SUNDAY NIGHT INTO MONDAY...AS THE S END OF
THE TROUGH DEEPENS ACROSS IOWA ON MONDAY. THE LOW WILL PUSH ACROSS
LOWER MICHIGAN ON TUESDAY...AND EXIT ACROSS THE LOWER GREAT LAKES
TUESDAY NIGHT. MONDAY NIGHT INTO TUESDAY NIGHT COULD BRING N WIND
GUSTING TO NEAR 30KTS OVER N AND E LAKE SUPERIOR.
HIGH PRESSURE STRETCHING FROM S CENTRAL CANADA THROUGH THE CENTRAL
PLAINS TUESDAY NIGHT WILL CROSS THE UPPER GREAT LAKES WEDNESDAY
NIGHT THROUGH THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KC
MARINE...KF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
121 PM EST SAT DEC 13 2014
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 328 AM EST SAT DEC 13 2014
LOW CLOUDS FOG AND DRIZZLE ARE EXPECTED TODAY AND SUNDAY BEFORE A
LOW PRESSURE SYSTEM APPROACHES AND GIVES US A CHANCE OF RAIN SUNDAY
NIGHT AND MONDAY. THE MILD WEATHER PATTERN WILL CONTINUE IN THE MID
TO UPPER 40S THROUGH MONDAY BEFORE COLDER WEATHER RETURNS TUESDAY.
&&
.UPDATE...
ISSUED AT 1048 AM EST SAT DEC 13 2014
I UPDATED OUR FORECAST TODAY TO HAVE AREAS OF FOG ALL DAY AND KEEP
THE SKY 100 PCT OVERCAST THROUGH TONIGHT. GIVEN THE STRENGTH OF
THE INVERSION (23 DEGREE/RAP13 15Z)...THE WARM ADVECTION GOING ON AND
HOW EXTENSIVE THE FOG AND LOW CLOUDS CURRENTLY ARE...IT IS HARD TO
IMAGINE THE FOG WILL BURN OFF TODAY. IN FACT THE HRRR IS BRINGING
SOME LIGHT RAIN TO WESTERN SECTIONS AFTER 4 PM...LIKELY THAT WOULD
BE DRIZZLE. THE RAP13 SOUNDING OVER GRR AT 15Z SHOWED THE AIR
TEMP. 28 DEGREE AT THE BASE OF THE INVERSION (1960 FT AGL) AND 51
DEGREES AT THE TOP OF THE INVERSION (3200 FT AGL). THAT IS ONE
IMPRESSIVE INVERSION FOR SURE. THE RAP13 SHOWS THAT THE LAYER BELOW
THE INVERSION STAYS SATURATED THROUGH THE DAY INTO THIS EVENING.
THUS SUPPORTING THE IDEA OF FOG AND LOW CLOUDS THROUGH THE DAY.
TEMPERATURE SHOULD RISE INTO THE 40S ACROSS THE CWA BY EVENING. IT
IS ALREADY IN THE LOW 40S AT HOLLAND AND MUSKEGON.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 328 AM EST SAT DEC 13 2014
FORECAST CONCERNS DEAL WITH THE STAGNANT WEATHER PATTERN AND
RESULTING LOW CLOUDS FOG AND DRIZZLE.
HIGH PRESSURE ALOFT AND AT THE SFC HAS CREATED A STAGNANT WEATHER
PATTERN THAT`S GOING TO LAST A COUPLE MORE DAYS. INCREASING LOW
LEVEL DEWPOINTS REPRESENTING HIGHER MOISTURE CONTENT ARE BEING
TRAPPED BENEATH AN INVERSION AND THAT IS RESULTING IN AREAS OF FOG
ACROSS THE CWA. IT DOESN`T LOOK LIKE THAT`S GOING TO CHANGE TODAY.
BUFKIT RH PROFILES REVEAL SOME LIFT WITHIN THE SHALLOW CLOUD DECK
WHICH MAY MANIFEST ITSELF AS LIGHT DRIZZLE AT TIMES THROUGH SUNDAY.
THE MOISTURE CONTENT AND LOW LEVEL LIFT INCREASE BY SUNDAY NIGHT AND
MONDAY AS THE SFC HIGH DRIFTS EAST AND LOW PRESSURE OVER THE PLAINS
MOVES EAST. CONDENSATION PRESSURE DEFICITS FALL TO AROUND 30 MB
MONDAY AFTERNOON WHICH WOULD CORRESPOND TO THE GREATEST CHANCE OF
LIGHT RAIN.
HIGH TEMPS WILL REMAIN ABOVE NORMAL THROUGH THE PERIOD HITTING THE
MID TO UPPER 40S THROUGH MONDAY. TEMPS SOUTH OF I-94 MAY SEE 50
MONDAY AFTERNOON. MEANWHILE LOW TEMPS LIKELY WON`T FALL BELOW
FREEZING THROUGH THE PERIOD.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 328 AM EST SAT DEC 13 2014
BEST CHANCES FOR RAIN WITH THE LOW PRESSURE SYSTEM MOVING THROUGH
THE AREA EARLY NEXT WEEK WILL COME ON MONDAY NIGHT. HAVE LIKELY
(70 PCT CHANCE) WORDING IN THE FORECAST AT THIS POINT IN MOST
PLACES. THE SYSTEM HAS A GOOD SOUTHERLY FEED OF MOISTURE THAT IS
LINKED TO THE GULF. THINKING WE ARE LOOKING AT RAINFALL TOTALS ON
THE ORDER OF 0.20 TO 0.40 ACROSS THE AREA.
THE MODELS HAVE CONTINUED WITH DIFFERING SOLUTIONS TONIGHT IN REGARD
TO THE PHASING OF UPPER SHORTWAVES FOR THE EARLY WEEK SYSTEM. THE
DIFFERENCES SHOW UP BEYOND THE MONDAY NIGHT TIME FRAME.
THE ECMWF PHASES THE NORTHERN AND SOUTHERN STREAM SHORTWAVES AND
HENCE PULLS IN COLDER AIR QUICKER...WHICH LINGERS INTO MID WEEK. THE
GFS CUTS THE NORTHERN SHORTWAVE OFF AND RETROGRADES IT ACROSS THE
NORTHERN PLAINS. CONFIDENCE IN HOW THIS PLAYS OUT IS STILL LOW...BUT
AM BECOMING MORE CONVINCED THE ECMWF HAS THE MORE PLAUSIBLE
SOLUTION.
THE ECMWF SOLUTION WILL KICK LAKE EFFECT SNOW IN TUESDAY NIGHT AFTER
A RAIN CHANGING TO SNOW MIX ON TUESDAY. EXPECTING LAKE EFFECT SNOW
SHOWERS FROM TUESDAY NIGHT INTO WEDNESDAY NIGHT. WOULD LIKE TO SEE
THE GFS COME ON BOARD WITH THE SAME EVOLUTION OF THE PATTERN MID
NEXT WEEK...WHICH WOULD BOOST CONFIDENCE. WILL BE WATCHING FUTURE
RUNS CLOSELY.
THINKING THURSDAY AND FRIDAY WILL BE DRY AND PARTLY CLOUDY BASED ON
THE ECMWF SOLUTION WITH HIGH PRESSURE SITUATED ACROSS THE AREA.
HIGHS ON TUESDAY WILL REACH THE LOWER 40S IN MANY AREAS. COLDER AIR
WILL PUSH IN QUICKLY TUESDAY NIGHT AND LINGER MUCH OF NEXT WEEK
TAKING HIGHS BACK TO NORMAL OR EVEN SLIGHTLY BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY)
ISSUED AT 1215 PM EST SAT DEC 13 2014
WIDESPREAD IFR TO LIFR CONDITIONS WILL CONTINUE THROUGH 18Z SUNDAY
DUE TO LOW CIGS AND LOW VISBYS DUE TO FOG. CIGS/VISBYS WILL LIKELY
TREND DOWN DURING THE EARLY MORNING HOURS SUNDAY WHEN SOME AREAS OF
DENSE FOG MAY ALSO AFFECT SOME OF THE TERMINALS. WINDS WILL STAY OUT
OF THE WSW MAINLY AOB 10 KTS THRU 18Z SUN.
&&
.MARINE...
ISSUED AT 328 AM EST SAT DEC 13 2014
HIGH PRESSURE OVERHEAD WILL RESULT IN FAIRLY LIGHT WINDS AND WAVES
AOB 4 FEET.
&&
.HYDROLOGY...
ISSUED AT 120 PM EST SAT DEC 13 2014
NO IMPACTS ARE EXPECTED ON AREA STREAMS AND RIVERS.
PRECIPITATION WILL RETURN LATE SUNDAY IN THE FORM OF RAIN. THE
BULK OF THIS SHOULD FALL BETWEEN SUNDAY NIGHT AND TUESDAY MORNING.
ENOUGH COLD AIR THEN MOVES IN THAT MAY CHANGE THE RAIN TO SNOW AS
WE GET INTO THE MIDDLE PART OF THE WEEK. TOTAL LIQUID ACCUMULATION
SHOULD BE IN THE RANGE OF 0.20-0.50...THIS WILL BE MORE OF A
BENEFIT TO THE AREA DUE TO RECENT DRY WEATHER.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...LAURENS
HYDROLOGY...JAM
MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1215 PM EST SAT DEC 13 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 328 AM EST SAT DEC 13 2014
LOW CLOUDS FOG AND DRIZZLE ARE EXPECTED TODAY AND SUNDAY BEFORE A
LOW PRESSURE SYSTEM APPROACHES AND GIVES US A CHANCE OF RAIN SUNDAY
NIGHT AND MONDAY. THE MILD WEATHER PATTERN WILL CONTINUE IN THE MID
TO UPPER 40S THROUGH MONDAY BEFORE COLDER WEATHER RETURNS TUESDAY.
&&
.UPDATE...
ISSUED AT 1048 AM EST SAT DEC 13 2014
I UPDATED OUR FORECAST TODAY TO HAVE AREAS OF FOG ALL DAY AND KEEP
THE SKY 100 PCT OVERCAST THROUGH TONIGHT. GIVEN THE STRENGTH OF
THE INVERSION (23 DEGREE/RAP13 15Z)...THE WARM ADVECTION GOING ON AND
HOW EXTENSIVE THE FOG AND LOW CLOUDS CURRENTLY ARE...IT IS HARD TO
IMAGINE THE FOG WILL BURN OFF TODAY. IN FACT THE HRRR IS BRINGING
SOME LIGHT RAIN TO WESTERN SECTIONS AFTER 4 PM...LIKELY THAT WOULD
BE DRIZZLE. THE RAP13 SOUNDING OVER GRR AT 15Z SHOWED THE AIR
TEMP. 28 DEGREE AT THE BASE OF THE INVERSION (1960 FT AGL) AND 51
DEGREES AT THE TOP OF THE INVERSION (3200 FT AGL). THAT IS ONE
IMPRESSIVE INVERSION FOR SURE. THE RAP13 SHOWS THAT THE LAYER BELOW
THE INVERSION STAYS SATURATED THROUGH THE DAY INTO THIS EVENING.
THUS SUPPORTING THE IDEA OF FOG AND LOW CLOUDS THROUGH THE DAY.
TEMPERATURE SHOULD RISE INTO THE 40S ACROSS THE CWA BY EVENING. IT
IS ALREADY IN THE LOW 40S AT HOLLAND AND MUSKEGON.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 328 AM EST SAT DEC 13 2014
FORECAST CONCERNS DEAL WITH THE STAGNANT WEATHER PATTERN AND
RESULTING LOW CLOUDS FOG AND DRIZZLE.
HIGH PRESSURE ALOFT AND AT THE SFC HAS CREATED A STAGNANT WEATHER
PATTERN THAT`S GOING TO LAST A COUPLE MORE DAYS. INCREASING LOW
LEVEL DEWPOINTS REPRESENTING HIGHER MOISTURE CONTENT ARE BEING
TRAPPED BENEATH AN INVERSION AND THAT IS RESULTING IN AREAS OF FOG
ACROSS THE CWA. IT DOESN`T LOOK LIKE THAT`S GOING TO CHANGE TODAY.
BUFKIT RH PROFILES REVEAL SOME LIFT WITHIN THE SHALLOW CLOUD DECK
WHICH MAY MANIFEST ITSELF AS LIGHT DRIZZLE AT TIMES THROUGH SUNDAY.
THE MOISTURE CONTENT AND LOW LEVEL LIFT INCREASE BY SUNDAY NIGHT AND
MONDAY AS THE SFC HIGH DRIFTS EAST AND LOW PRESSURE OVER THE PLAINS
MOVES EAST. CONDENSATION PRESSURE DEFICITS FALL TO AROUND 30 MB
MONDAY AFTERNOON WHICH WOULD CORRESPOND TO THE GREATEST CHANCE OF
LIGHT RAIN.
HIGH TEMPS WILL REMAIN ABOVE NORMAL THROUGH THE PERIOD HITTING THE
MID TO UPPER 40S THROUGH MONDAY. TEMPS SOUTH OF I-94 MAY SEE 50
MONDAY AFTERNOON. MEANWHILE LOW TEMPS LIKELY WON`T FALL BELOW
FREEZING THROUGH THE PERIOD.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 328 AM EST SAT DEC 13 2014
BEST CHANCES FOR RAIN WITH THE LOW PRESSURE SYSTEM MOVING THROUGH
THE AREA EARLY NEXT WEEK WILL COME ON MONDAY NIGHT. HAVE LIKELY
(70 PCT CHANCE) WORDING IN THE FORECAST AT THIS POINT IN MOST
PLACES. THE SYSTEM HAS A GOOD SOUTHERLY FEED OF MOISTURE THAT IS
LINKED TO THE GULF. THINKING WE ARE LOOKING AT RAINFALL TOTALS ON
THE ORDER OF 0.20 TO 0.40 ACROSS THE AREA.
THE MODELS HAVE CONTINUED WITH DIFFERING SOLUTIONS TONIGHT IN REGARD
TO THE PHASING OF UPPER SHORTWAVES FOR THE EARLY WEEK SYSTEM. THE
DIFFERENCES SHOW UP BEYOND THE MONDAY NIGHT TIME FRAME.
THE ECMWF PHASES THE NORTHERN AND SOUTHERN STREAM SHORTWAVES AND
HENCE PULLS IN COLDER AIR QUICKER...WHICH LINGERS INTO MID WEEK. THE
GFS CUTS THE NORTHERN SHORTWAVE OFF AND RETROGRADES IT ACROSS THE
NORTHERN PLAINS. CONFIDENCE IN HOW THIS PLAYS OUT IS STILL LOW...BUT
AM BECOMING MORE CONVINCED THE ECMWF HAS THE MORE PLAUSIBLE
SOLUTION.
THE ECMWF SOLUTION WILL KICK LAKE EFFECT SNOW IN TUESDAY NIGHT AFTER
A RAIN CHANGING TO SNOW MIX ON TUESDAY. EXPECTING LAKE EFFECT SNOW
SHOWERS FROM TUESDAY NIGHT INTO WEDNESDAY NIGHT. WOULD LIKE TO SEE
THE GFS COME ON BOARD WITH THE SAME EVOLUTION OF THE PATTERN MID
NEXT WEEK...WHICH WOULD BOOST CONFIDENCE. WILL BE WATCHING FUTURE
RUNS CLOSELY.
THINKING THURSDAY AND FRIDAY WILL BE DRY AND PARTLY CLOUDY BASED ON
THE ECMWF SOLUTION WITH HIGH PRESSURE SITUATED ACROSS THE AREA.
HIGHS ON TUESDAY WILL REACH THE LOWER 40S IN MANY AREAS. COLDER AIR
WILL PUSH IN QUICKLY TUESDAY NIGHT AND LINGER MUCH OF NEXT WEEK
TAKING HIGHS BACK TO NORMAL OR EVEN SLIGHTLY BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY)
ISSUED AT 1215 PM EST SAT DEC 13 2014
WIDESPREAD IFR TO LIFR CONDITIONS WILL CONTINUE THROUGH 18Z SUNDAY
DUE TO LOW CIGS AND LOW VISBYS DUE TO FOG. CIGS/VISBYS WILL LIKELY
TREND DOWN DURING THE EARLY MORNING HOURS SUNDAY WHEN SOME AREAS OF
DENSE FOG MAY ALSO AFFECT SOME OF THE TERMINALS. WINDS WILL STAY OUT
OF THE WSW MAINLY AOB 10 KTS THRU 18Z SUN.
&&
.MARINE...
ISSUED AT 328 AM EST SAT DEC 13 2014
HIGH PRESSURE OVERHEAD WILL RESULT IN FAIRLY LIGHT WINDS AND WAVES
AOB 4 FEET.
&&
.HYDROLOGY...
ISSUED AT 328 AM EST SAT DEC 13 2014
NO HYDRO ISSUES DUE TO RELATIVELY DRY WEATHER.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...LAURENS
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1049 AM EST SAT DEC 13 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 328 AM EST SAT DEC 13 2014
LOW CLOUDS FOG AND DRIZZLE ARE EXPECTED TODAY AND SUNDAY BEFORE A
LOW PRESSURE SYSTEM APPROACHES AND GIVES US A CHANCE OF RAIN SUNDAY
NIGHT AND MONDAY. THE MILD WEATHER PATTERN WILL CONTINUE IN THE MID
TO UPPER 40S THROUGH MONDAY BEFORE COLDER WEATHER RETURNS TUESDAY.
&&
.UPDATE...
ISSUED AT 1048 AM EST SAT DEC 13 2014
I UPDATED OUR FORECAST TODAY TO HAVE AREAS OF FOG ALL DAY AND KEEP
THE SKY 100 PCT OVERCAST THROUGH TONIGHT. GIVEN THE STRENGTH OF
THE INVERSION (23 DEGREE/RAP13 15Z)...THE WARM ADVECTION GOING ON AND
HOW EXTENSIVE THE FOG AND LOW CLOUDS CURRENTLY ARE...IT IS HARD TO
IMAGINE THE FOG WILL BURN OFF TODAY. IN FACT THE HRRR IS BRINGING
SOME LIGHT RAIN TO WESTERN SECTIONS AFTER 4 PM...LIKELY THAT WOULD
BE DRIZZLE. THE RAP13 SOUNDING OVER GRR AT 15Z SHOWED THE AIR
TEMP. 28 DEGREE AT THE BASE OF THE INVERSION (1960 FT AGL) AND 51
DEGREES AT THE TOP OF THE INVERSION (3200 FT AGL). THAT IS ONE
IMPRESSIVE INVERSION FOR SURE. THE RAP13 SHOWS THAT THE LAYER BELOW
THE INVERSION STAYS SATURATED THROUGH THE DAY INTO THIS EVENING.
THUS SUPPORTING THE IDEA OF FOG AND LOW CLOUDS THROUGH THE DAY.
TEMPERATURE SHOULD RISE INTO THE 40S ACROSS THE CWA BY EVENING. IT
IS ALREADY IN THE LOW 40S AT HOLLAND AND MUSKEGON.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 328 AM EST SAT DEC 13 2014
FORECAST CONCERNS DEAL WITH THE STAGNANT WEATHER PATTERN AND
RESULTING LOW CLOUDS FOG AND DRIZZLE.
HIGH PRESSURE ALOFT AND AT THE SFC HAS CREATED A STAGNANT WEATHER
PATTERN THAT`S GOING TO LAST A COUPLE MORE DAYS. INCREASING LOW
LEVEL DEWPOINTS REPRESENTING HIGHER MOISTURE CONTENT ARE BEING
TRAPPED BENEATH AN INVERSION AND THAT IS RESULTING IN AREAS OF FOG
ACROSS THE CWA. IT DOESN`T LOOK LIKE THAT`S GOING TO CHANGE TODAY.
BUFKIT RH PROFILES REVEAL SOME LIFT WITHIN THE SHALLOW CLOUD DECK
WHICH MAY MANIFEST ITSELF AS LIGHT DRIZZLE AT TIMES THROUGH SUNDAY.
THE MOISTURE CONTENT AND LOW LEVEL LIFT INCREASE BY SUNDAY NIGHT AND
MONDAY AS THE SFC HIGH DRIFTS EAST AND LOW PRESSURE OVER THE PLAINS
MOVES EAST. CONDENSATION PRESSURE DEFICITS FALL TO AROUND 30 MB
MONDAY AFTERNOON WHICH WOULD CORRESPOND TO THE GREATEST CHANCE OF
LIGHT RAIN.
HIGH TEMPS WILL REMAIN ABOVE NORMAL THROUGH THE PERIOD HITTING THE
MID TO UPPER 40S THROUGH MONDAY. TEMPS SOUTH OF I-94 MAY SEE 50
MONDAY AFTERNOON. MEANWHILE LOW TEMPS LIKELY WON`T FALL BELOW
FREEZING THROUGH THE PERIOD.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 328 AM EST SAT DEC 13 2014
BEST CHANCES FOR RAIN WITH THE LOW PRESSURE SYSTEM MOVING THROUGH
THE AREA EARLY NEXT WEEK WILL COME ON MONDAY NIGHT. HAVE LIKELY
(70 PCT CHANCE) WORDING IN THE FORECAST AT THIS POINT IN MOST
PLACES. THE SYSTEM HAS A GOOD SOUTHERLY FEED OF MOISTURE THAT IS
LINKED TO THE GULF. THINKING WE ARE LOOKING AT RAINFALL TOTALS ON
THE ORDER OF 0.20 TO 0.40 ACROSS THE AREA.
THE MODELS HAVE CONTINUED WITH DIFFERING SOLUTIONS TONIGHT IN REGARD
TO THE PHASING OF UPPER SHORTWAVES FOR THE EARLY WEEK SYSTEM. THE
DIFFERENCES SHOW UP BEYOND THE MONDAY NIGHT TIME FRAME.
THE ECMWF PHASES THE NORTHERN AND SOUTHERN STREAM SHORTWAVES AND
HENCE PULLS IN COLDER AIR QUICKER...WHICH LINGERS INTO MID WEEK. THE
GFS CUTS THE NORTHERN SHORTWAVE OFF AND RETROGRADES IT ACROSS THE
NORTHERN PLAINS. CONFIDENCE IN HOW THIS PLAYS OUT IS STILL LOW...BUT
AM BECOMING MORE CONVINCED THE ECMWF HAS THE MORE PLAUSIBLE
SOLUTION.
THE ECMWF SOLUTION WILL KICK LAKE EFFECT SNOW IN TUESDAY NIGHT AFTER
A RAIN CHANGING TO SNOW MIX ON TUESDAY. EXPECTING LAKE EFFECT SNOW
SHOWERS FROM TUESDAY NIGHT INTO WEDNESDAY NIGHT. WOULD LIKE TO SEE
THE GFS COME ON BOARD WITH THE SAME EVOLUTION OF THE PATTERN MID
NEXT WEEK...WHICH WOULD BOOST CONFIDENCE. WILL BE WATCHING FUTURE
RUNS CLOSELY.
THINKING THURSDAY AND FRIDAY WILL BE DRY AND PARTLY CLOUDY BASED ON
THE ECMWF SOLUTION WITH HIGH PRESSURE SITUATED ACROSS THE AREA.
HIGHS ON TUESDAY WILL REACH THE LOWER 40S IN MANY AREAS. COLDER AIR
WILL PUSH IN QUICKLY TUESDAY NIGHT AND LINGER MUCH OF NEXT WEEK
TAKING HIGHS BACK TO NORMAL OR EVEN SLIGHTLY BELOW NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 646 AM EST SAT DEC 13 2014
NO IMPROVEMENT IS EXPECTED FROM THE LOW CEILINGS AND FOG THE NEXT
24 HOURS. WIDESPREAD IFR AND EVEN SOME LIFR IS IN PLACE ACROSS THE
AREA AT 12Z. THERE MAY BE A SLIGHT RISE IN CEILINGS TODAY...BUT
OVERALL EXPECTING THEM TO REMAIN BELOW 1000FT. FOG WILL LIKELY
REMAIN IN THE 3-5 STATUTE MILE RANGE TODAY.
TONIGHT CEILINGS AND VISIBILITIES WILL LIKELY TREND DOWN ONCE
AGAIN WITH LIFR/IFR REMAINING IN PLACE.
WINDS WILL BE FROM THE WEST-SOUTHWEST THE NEXT 24 HOURS AT 7-12
KNOTS.
&&
.MARINE...
ISSUED AT 328 AM EST SAT DEC 13 2014
HIGH PRESSURE OVERHEAD WILL RESULT IN FAIRLY LIGHT WINDS AND WAVES
AOB 4 FEET.
&&
.HYDROLOGY...
ISSUED AT 328 AM EST SAT DEC 13 2014
NO HYDRO ISSUES DUE TO RELATIVELY DRY WEATHER.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1242 PM EST FRI DEC 12 2014
.AVIATION...
//DISCUSSION...
LOW STRATUS WILL CONTINUE TO COVER MOST OF SE MICHIGAN DURING THE
TAF PERIOD AS VERY LOW INVERSION HEIGHT SUPPORTS BORDERLINE MVFR/IFR
CEILINGS. ALTHOUGH HIGH PRESSURE IS EXPECTED TO BUILD IN
TONIGHT...THIS WILL ONLY STRENGTHEN THE INVERSION AND LOWER CIGS
FURTHER AS THE MOISTURE IS TRAPPED IN THE LOW LEVELS. THEREFORE WILL
MAINTAIN THE STRATUS THROUGH THE TAF PERIOD.
//DTW THRESHOLD THREATS...
* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET THROUGH THE TAF PERIOD.
&&
.PREV DISCUSSION...ISSUED 352 AM EST FRI DEC 12 2014
SHORT TERM...TODAY AND TONIGHT
SE MICHIGAN WILL REMAIN JUST DOWNSTREAM OF HIGH AMPLITUDE UPPER
RIDGING OVER THE NEXT 24 HOURS...THIS POSITIONING SUSTAINING A
NORTHWEST FLOW JUST OFF THE SURFACE. THE ASSOCIATED MID LEVEL
SUBSIDENCE AND SUBSTANTIAL DRY LAYER MARKING CONDITIONS WITHIN THE
BURGEONING INVERSION LAYER ABOVE 925 MB WILL TRANSLATE INTO A STABLE
PROFILE TODAY. HOWEVER CLOUD TRENDS WILL BECOME AN INCREASING ISSUE
AS A PERIOD OF WEAK 925 MB COLD AIR ADVECTION/THERMAL TROUGHING
WORKING SOUTHEAST DOWN THE BACKSIDE OF THE RIDGE PERIPHERY
EFFECTIVELY SATURATES THE THIN 925-950 MB SUB-INVERSION LAYER.
RECENT NAM AND RAP RH FIELDS AT THIS LEVEL CORRESPOND WELL WITH THE
SOUTHWARD EXPANDING SOLID STRATUS DECK NOW MOVING INTO THE REGION.
THIS MOISTURE IS FORECAST TO HOLD FIRM OVER SOUTHEAST MICHIGAN WELL
INTO THE DAY. THE OVERALL SETUP POINTS TOWARD SEEING A DEFINITIVE
SOUTHWEST EDGE TO THE STRATUS DECK...PROVIDING SOME UNCERTAINTY YET
IN POTENTIAL CLOUD COVERAGE FOR LOCALES TOWARD THE SOUTH. THESE
TRENDS SUPPORT TAKING A MORE CONSERVATIVE APPROACH ON HIGHS
TODAY...READINGS MAINLY MID 30S.
SLIGHTLY WARMER AND DRIER FLOW WILL ATTEMPT TO DIMINISH THE CLOUD
COVERAGE THIS EVENING/TONIGHT...BUT CONFIDENCE IS CERTAINLY LOW ON
THE CLOUD TRENDS GOING FORWARD UNDER THIS PATTERN. THE POTENTIAL
WILL EXIST FOR THE EXISTING MOIST LAYER TO HOLD FIRM BENEATH THE
INVERSION...LEAVING A LARGE MAJORITY OF THE AREA SOCKED UNDER A
PERSISTENT OVERCAST CONDITION. PLAN TO LEAN IN THIS DIRECTION AT
THIS TIME. LOWS TONIGHT UPPER 20S.
LONG TERM...
HIGH PRESSURE THAT IS FIRMLY IN PLACE FROM THE UPPER MIDWEST ALL THE
WAY TO THE CENTRAL GULF COAST TODAY WILL BE NUDGED EASTWARD SATURDAY
BY THE POWERFUL PACIFIC COAST STORM AS IT MOVES INLAND. THIS WILL
GUARD SE MICHIGAN FROM ANY POTENTIAL FOR SIGNIFICANT PRECIPITATION
AND GUIDE A WARMING TREND THROUGH THE WEEKEND...BUT THE OVERALL
OPTIMISM IN THE FORECAST WILL BE TEMPERED BY AN INCREASING AMOUNT OF
CLOUDS EACH DAY. SUNDAY CONTINUES TO LOOK LIKE A GLOOMY DAY FULL OF
CLOUDS AND DRIZZLE SOFTENED BY MAX TEMPS PUSHING THE MID 40S OR
ABOUT 10 DEGREES ABOVE NORMAL FOR THE SECOND WEEKEND OF DECEMBER.
EARLY MORNING SATELLITE IMAGERY TODAY SHOWS WIDESPREAD STRATUS ALONG
AND WEST OF THE SURFACE RIDGE AXIS THROUGHOUT THE CENTRAL U.S. AND
CANADA. THESE CLOUDS WERE STRONGLY RESISTANT TO THE INFLUENCE OF
DIURNAL WARMING DURING THURSDAY...A STRONG SIGN THE LOW LEVEL
MOISTURE IS LOCKED UNDER THE SUBSIDENCE INVERSION ASSOCIATED WITH
THE HIGH AMPLITUDE UPPER LEVEL RIDGE. EXPECT THE ENTIRE PATTERN TO
DRIFT EASTWARD THROUGH TODAY AND SATURDAY AND BRING OUR AREA UNDER
INCREASING INFLUENCE OF THIS LOW LEVEL MOISTURE. THE CLOUDS WILL
HAVE INCONSISTENT COVERAGE OFF THE LAKES WHILE THERE IS STILL A
NORTHWEST COMPONENT TO THE LOW LEVEL FLOW BUT THEN SURGE LATE
SATURDAY AND SATURDAY NIGHT AS THE SURFACE HIGH SETTLES INTO THE
OHIO VALLEY ALLOW A BACKING WIND FIELD OVER LOWER MICHIGAN. A FEW
100THS QPF INDICATED ACROSS THE 00Z MODEL SOLUTIONS...BUT UNDER DRY
850-500 MB LAYER RH...IS A GOOD INDICATOR OF DRIZZLE LATE SATURDAY
NIGHT THROUGH SUNDAY. THIS IS BACKED UP BY SREF ENSEMBLE SOUNDINGS
THAT SHOW DEEPENING BOUNDARY LAYER MOISTURE DURING THIS TIME WITH A
STEEP INVERSION AND MODEST SPEED SHEAR. EXPECT ALL BUT THE MOST
SHELTERED LOCATIONS IN THE THUMB WILL BE ABOVE THE FREEZING MARK BY
SUNRISE SUNDAY MAKING FREEZING POTENTIAL A MINIMAL CONCERN BEFORE
READINGS REACH THE 40S SUNDAY AFTERNOON...AND THEN ONLY DROP BACK TO
AROUND 40 SUNDAY NIGHT.
THE POWERFUL PACIFIC COAST STORM MOVING INLAND TODAY WILL REACH THE
SOUTHERN PLAINS BY MONDAY. MODEL AGREEMENT IS IMPROVING BUT STILL
SHOWS DIFFERENCES IN TIMING ON THE EASTWARD PACE OF THE SYSTEM.
PREFER SLOWER SOLUTIONS FOR THE GREAT LAKES GIVEN THE CONTINUED HIGH
AMPLITUDE LONG WAVE PATTERN HIGHLIGHTED BY THE FORMIDABLE RIDGE AXIS
AND NOR` EASTER COMBO OFF THE ATLANTIC COAST. SLOWER TIMING WILL
HELP ENSURE A SHORT WAVE TRACK TO OUR WEST AND A WARM OUTCOME FOR
PRECIPITATION TYPE. OUR GOING FORECAST HAS THIS HANDLED WELL WITH
ALL RAIN CENTERED ON TUESDAY IN SE MICHIGAN. THIS IS FOLLOWED BY A
RETURN TO A BLOCKING PATTERN FOR THE SECOND HALF OF THE WEEK BUT
CHAOTIC MODEL DEPICTIONS SUGGEST THE LOCATION OF EVEN THE LARGER
SCALE UPPER AIR FEATURES ARE IN QUESTION.
MARINE...
SMALL CRAFT ADVISORIES WILL REMAIN IN EFFECT FOR OUTER SAGINAW BAY
AROUND TO HARBOR BEACH FOR LINGERING ROUGH WATER DURING THE EARLY
MORNING. A SLOWLY DECREASING DOWNWARD TREND IN WIND AND WAVES WILL
CONTINUE OVER ALL MARINE AREAS AS HIGH PRESSURE BUILDS INTO THE
CENTRAL GREAT LAKES TODAY. MILDER AIR STREAMING INTO THE REGION OVER
THE WEEKEND WILL LEAD TO STABLE PROFILES...AND CORRESPONDING LIGHT
WINDS AND LOW WAVES THROUGH EARLY NEXT WEEK.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....KURIMSKI
SHORT TERM...MR
LONG TERM....BT
MARINE.......BT
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
654 AM EST FRI DEC 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM EST FRI DEC 12 2014
YET ANOTHER FORECAST SHIFT SPENT TRYING TO FIGURE OUT CLOUD AND FOG
COVERAGE ASSOCIATED WITH MOISTURE TRAPPED BENEATH THE INVERSION IN
THE LOWEST 50MB OF THE ATMOSPHERE. AIR ABOVE THE INVERSION IS MUCH
WARMER /850MB TEMPS UP TO 12C IN THE SHORT TERM/ AND VERY DRY
/925-700MB LAYER RH LESS THAN 25 PERCENT/. AS WE HAVE SEEN OVER THE
LAST COUPLE OF DAYS...THE LOW LEVEL CLOUDS/FOG ARE VERY PERSISTENT
AND LARGELY CONFINED TO AREAS DOWNWIND OF LAKE SUPERIOR /AT LEAST
OVER THE MQT CWA/. HOWEVER...INLAND LOW CLOUDS HAVE BEEN
CONSISTENTLY OBSERVED TO THE W ALONG AND BEHIND THE SFC RIDGE
AXIS...WHICH WILL CROSS THE CWA TODAY. THINK THIS WILL PROMOTE
GREATER CLOUD COVERAGE TODAY THAN YESTERDAY...WITH THE BEST CHANCES
FOR LESS CLOUD COVERAGE IN DOWNSLOPING AREAS NEAR LAKE SUPERIOR NEAR
ONTONAGON AND ADDITIONALLY FROM BARAGA TO BIG BAY AND ON THE
MARQUETTE AND AU TRAIN AS ANTICYCLONIC WIND FLOW WILL HAVE
TRAJECTORIES FROM WRN LAKE SUPERIOR TO THE KEWEENAW
PENINSULA/CENTRAL LAKE SUPERIOR AND THEN TO THE ERN U.P. AND ERN
LAKE SUPERIOR. FOR THE FOG...KEPT IT CONFINED MAINLY TO THE KEWEENAW
AND ERN U.P. BY THIS AFTERNOON...THEN ADDED INLAND AREAS TONIGHT AS
NOCTURNAL FOG DEVELOPMENT APPEARS LIKELY.
KEPT HIGH TEMPS NEAR FREEZING TODAY GIVEN THE STRENGTH OF THE
INVERSION AND EXPECTED CLOUD COVER. HAVE LOWS TONIGHT IN THE MID TO
UPPER 20S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 522 AM EST FRI DEC 12 2014
AN UNSEASONABLY STRONG RIDGE THROUGH THE CENTRAL CONUS THIS WEEKEND
IS EXPECTED TO GRADUALLY SHIFT TO THE EAST EARLY NEXT WEEK AS
SHORTWAVES IN SPLIT FLOW PATTERN BEGIN TO INTERACT LEAVING A TROUGH
THROUGH THE NRN LAKES. VERY MILD CONDITIONS ARE EXPECTED WITH A
GRADUAL COOL DOWN BY TUE WITH TEMPS CLOSER TO AVERAGE THROUGH THE
REST OF THE WEEK.
SATURDAY...WARM ADVECTION JUST ABOVE THE SURFACE PUSHING 850 MB TEMPS
INTO THE 12C TO 14C RANGE WILL RESULT IN A VERY STRONG INVERSION
THAT SHOULD INHIBIT MIXING TOWARD THE SFC. EXPECT THAT THERE WILL BE
ENOUGH LOW LEVEL MOISTURE BENEATH THE INVERSION TO SUSTAIN MOSTLY
CLOUDY SKIES AS HAS BEEN THE CASE OVER MOST OF THE REGION TO THE
WEST. HOWEVER...THERE MAY BE SOME BREAKS BY AFTERNOON ESPECIALLY CENTRAL
WHERE DOWNSLOPE WRLY FLOW PREVAILS. OTHERWISE...TEMPS SHOULD CLIMB
TO AROUND 40.
SAT NIGHT INTO SUN...EXPECT SOME DRIZZLE TO DEVELOP AS WEAK UPWARD
MOTION PREVAILS ABOVE THE LOW LEVEL MOISTURE THICKENING ACROSS UPPER
MI AHEAD OF THE TROUGH SLIDING INTO THE UPPER MS VALLEY. IN
ADDITION...MELTING SNOW WILL ADD ADDITIONAL MOISTURE TO SUPPORT
DEVELOPMENT OF AREAS OF DENSE FOG.
MON INTO MON NIGHT...THE GFS/ECMWF/UKMET HAVE TRENDED TOWARD A MORE
PHASED SOLUTION WITH THE NRN AND SRN STREAM SHORTWAVES THAT PRODUCES
A STRONGER SFC LOW THAT MOVES FARTHER NORTH INTO THE WRN LAKES. THIS
WOULD DELAY THE INTRUSION OF COLDER AIR WITH MAINLY RAIN LINGERING
THROUGH MON NIGHT. THE GEM AND A LARGE NUMBER OF GFS ENSEMBLE
MEMBERS STILL FAVOR A LESS PHASED SYSTEM WITH A MORE SRLY TRACK OF
THE LOW. CONFIDENCE IN THE EVOLUTION OF THE SYSTEM IS STILL LOW
GIVEN THE SIGNIFICANT CHANGE FROM PREVIOUS MODEL SOLUTIONS. THE FCST
STILL REFLECTS THE POTENTIAL FOR AN EARLIER CHANGEOVER TO SNOW...PER
PREVIOUS MDLS SOLUTIONS.
TUE-THU...COLDER AIR WILL FINALLY MOVE IN BEHIND THE LOW WITH
POSSIBILITY OF SOME LIGHT SNOW ASSOCIATED WITH FORCING ASSOCIATED
WITH THE MID LEVEL LOW AND SOME LAKE ENHANCEMENT OFF OF LAKE
SUPERIOR. A MORE NRLY LOW TRACK WOULD BRING THE BEST SNOW CHANCES
FOR LOCATIONS FAVORED BY WNW FLOW. MODEL DIFFERENCES ARE EVEN LARGER
BY THU AS THE ECMWF BRINGS MID LEVEL AND SFC RIDGING BACK TOWARD THE
WRN LAKES WHILE THE GFS LEAVES THE MID LEVEL LOW NEAR THE DAKOTAS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 653 AM EST FRI DEC 12 2014
AT IWD...EXPECT IMPROVEMENT IN CONDITIONS THIS AFTERNOON AS WINDS
TURN OUT OF THE SSW...WHICH WILL BE MORE OF A DOWNSLOPING WIND. FOG
MAY DEVELOP NEAR OR AT THE AIRPORT TONIGHT...BUT AM UNCERTAIN OF THE
EXTENT.
AT CMX...DO NOT EXPECT MUCH CHANGE IN CONDITIONS TODAY EXCEPT THAT
VIS SHOULD IMPROVE SOME. WINDS LOOK TO TURN ENOUGH OUT OF THE SSW
TONIGHT TO KEEP THE INCREASED MOISTURE OVER LAKE SUPERIOR OUT OF THE
AIRPORT. CLOUDS/FOG SHOULD MOVE BACK IN AROUND THE END OF THE TAF
TIME...BUT DID NOT REFLECT THAT IN THIS TAF. AM QUITE UNCERTAIN ON
TIMING/EXTENT OF IMPROVEMENT TONIGHT GIVEN UNCERTAINTY IN EXACT WIND
DIRECTION.
AT SAW...LOW LEVEL CLOUDS HAVE MADE IT INTO THE SITE THIS
MORNING...BUT AS ABOVE SURFACE WINDS TURN MORE OUT OF THE W THIS
AFTERNOON...DOWNSLOPING SHOULD RESULT IN IMPROVING CONDITIONS.
FOG/LOW CIGS MAY DEVELOP TONIGHT...BUT AM UNCERTAIN ON THE EXTENT.
MAINLY USED A BLEND OF THE NAM AND HRRR (WHEN AVAILABLE) FOR CIGS
AND THE NAM...LAMP AND NCEP HIGH-RES WRF FOR VIS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 344 AM EST FRI DEC 12 2014
W TO NW WINDS UP TO 20 KTS EARLY THIS MORNING THE N OF A HIGH CENTER
IN THE MID MISSISSIPPI RIVER VALLEY WILL BACK TO THE SW OVER THE
WEEKEND AS THIS HIGH SHIFTS TO THE E THROUGH THE OHIO RIVER VALLEY.
THE WINDS WILL REMAIN RELATIVELY LIGHT WITH UNUSUALLY HIGH STABILITY
OVER THE WATERS. FOLLOWING THE PASSAGE OF A COLD FRONT ON MON...N
WINDS WILL INCREASE UP TO 25-30 KTS EARLY NEXT WEEK UNDER TIGHTENING
PRESSURE GRADIENT AHEAD OF HIGH PRESSURE MOVING INTO SCENTRAL CANADA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...TITUS
LONG TERM...JLB
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
640 AM EST FRI DEC 12 2014
.AVIATION...
//DISCUSSION...
LOW STRATUS WILL COVER MOST OF SE MICHIGAN DURING THE MORNING AS
VERY LOW INVERSION HEIGHT SUPPORTS BORDERLINE MVFR/IFR CEILING. WEAK
MIXING DURING THE DAY WILL THEN HELP LIFT BASES INTO LOWER MVFR ALL
AREAS BY AFTERNOON. LOWER CONFIDENCE ON THE PROSPECTS OF SEEING
CLEARING TONIGHT GIVEN THE HIGH DEGREE OF MOISTURE AROUND 925 MB.
AT THIS TIME WILL LEAN MORE PESSIMISTIC IN SUSTAINING MVFR STRATUS
THROUGH TONIGHT.
//DTW THRESHOLD THREATS...
* HIGH CONFIDENCE IN CEILING BELOW 5000 FEET TODAY...LOW CONFIDENCE
TONIGHT.
&&
.PREV DISCUSSION...ISSUED 352 AM EST FRI DEC 12 2014
SHORT TERM...TODAY AND TONIGHT
SE MICHIGAN WILL REMAIN JUST DOWNSTREAM OF HIGH AMPLITUDE UPPER
RIDGING OVER THE NEXT 24 HOURS...THIS POSITIONING SUSTAINING A
NORTHWEST FLOW JUST OFF THE SURFACE. THE ASSOCIATED MID LEVEL
SUBSIDENCE AND SUBSTANTIAL DRY LAYER MARKING CONDITIONS WITHIN THE
BURGEONING INVERSION LAYER ABOVE 925 MB WILL TRANSLATE INTO A STABLE
PROFILE TODAY. HOWEVER CLOUD TRENDS WILL BECOME AN INCREASING ISSUE
AS A PERIOD OF WEAK 925 MB COLD AIR ADVECTION/THERMAL TROUGHING
WORKING SOUTHEAST DOWN THE BACKSIDE OF THE RIDGE PERIPHERY
EFFECTIVELY SATURATES THE THIN 925-950 MB SUB-INVERSION LAYER.
RECENT NAM AND RAP RH FIELDS AT THIS LEVEL CORRESPOND WELL WITH THE
SOUTHWARD EXPANDING SOLID STRATUS DECK NOW MOVING INTO THE REGION.
THIS MOISTURE IS FORECAST TO HOLD FIRM OVER SOUTHEAST MICHIGAN WELL
INTO THE DAY. THE OVERALL SETUP POINTS TOWARD SEEING A DEFINITIVE
SOUTHWEST EDGE TO THE STRATUS DECK...PROVIDING SOME UNCERTAINTY YET
IN POTENTIAL CLOUD COVERAGE FOR LOCALES TOWARD THE SOUTH. THESE
TRENDS SUPPORT TAKING A MORE CONSERVATIVE APPROACH ON HIGHS
TODAY...READINGS MAINLY MID 30S.
SLIGHTLY WARMER AND DRIER FLOW WILL ATTEMPT TO DIMINISH THE CLOUD
COVERAGE THIS EVENING/TONIGHT...BUT CONFIDENCE IS CERTAINLY LOW ON
THE CLOUD TRENDS GOING FORWARD UNDER THIS PATTERN. THE POTENTIAL
WILL EXIST FOR THE EXISTING MOIST LAYER TO HOLD FIRM BENEATH THE
INVERSION...LEAVING A LARGE MAJORITY OF THE AREA SOCKED UNDER A
PERSISTENT OVERCAST CONDITION. PLAN TO LEAN IN THIS DIRECTION AT
THIS TIME. LOWS TONIGHT UPPER 20S.
LONG TERM...
HIGH PRESSURE THAT IS FIRMLY IN PLACE FROM THE UPPER MIDWEST ALL THE
WAY TO THE CENTRAL GULF COAST TODAY WILL BE NUDGED EASTWARD SATURDAY
BY THE POWERFUL PACIFIC COAST STORM AS IT MOVES INLAND. THIS WILL
GUARD SE MICHIGAN FROM ANY POTENTIAL FOR SIGNIFICANT PRECIPITATION
AND GUIDE A WARMING TREND THROUGH THE WEEKEND...BUT THE OVERALL
OPTIMISM IN THE FORECAST WILL BE TEMPERED BY AN INCREASING AMOUNT OF
CLOUDS EACH DAY. SUNDAY CONTINUES TO LOOK LIKE A GLOOMY DAY FULL OF
CLOUDS AND DRIZZLE SOFTENED BY MAX TEMPS PUSHING THE MID 40S OR
ABOUT 10 DEGREES ABOVE NORMAL FOR THE SECOND WEEKEND OF DECEMBER.
EARLY MORNING SATELLITE IMAGERY TODAY SHOWS WIDESPREAD STRATUS ALONG
AND WEST OF THE SURFACE RIDGE AXIS THROUGHOUT THE CENTRAL U.S. AND
CANADA. THESE CLOUDS WERE STRONGLY RESISTANT TO THE INFLUENCE OF
DIURNAL WARMING DURING THURSDAY...A STRONG SIGN THE LOW LEVEL
MOISTURE IS LOCKED UNDER THE SUBSIDENCE INVERSION ASSOCIATED WITH
THE HIGH AMPLITUDE UPPER LEVEL RIDGE. EXPECT THE ENTIRE PATTERN TO
DRIFT EASTWARD THROUGH TODAY AND SATURDAY AND BRING OUR AREA UNDER
INCREASING INFLUENCE OF THIS LOW LEVEL MOISTURE. THE CLOUDS WILL
HAVE INCONSISTENT COVERAGE OFF THE LAKES WHILE THERE IS STILL A
NORTHWEST COMPONENT TO THE LOW LEVEL FLOW BUT THEN SURGE LATE
SATURDAY AND SATURDAY NIGHT AS THE SURFACE HIGH SETTLES INTO THE
OHIO VALLEY ALLOW A BACKING WIND FIELD OVER LOWER MICHIGAN. A FEW
100THS QPF INDICATED ACROSS THE 00Z MODEL SOLUTIONS...BUT UNDER DRY
850-500 MB LAYER RH...IS A GOOD INDICATOR OF DRIZZLE LATE SATURDAY
NIGHT THROUGH SUNDAY. THIS IS BACKED UP BY SREF ENSEMBLE SOUNDINGS
THAT SHOW DEEPENING BOUNDARY LAYER MOISTURE DURING THIS TIME WITH A
STEEP INVERSION AND MODEST SPEED SHEAR. EXPECT ALL BUT THE MOST
SHELTERED LOCATIONS IN THE THUMB WILL BE ABOVE THE FREEZING MARK BY
SUNRISE SUNDAY MAKING FREEZING POTENTIAL A MINIMAL CONCERN BEFORE
READINGS REACH THE 40S SUNDAY AFTERNOON...AND THEN ONLY DROP BACK TO
AROUND 40 SUNDAY NIGHT.
THE POWERFUL PACIFIC COAST STORM MOVING INLAND TODAY WILL REACH THE
SOUTHERN PLAINS BY MONDAY. MODEL AGREEMENT IS IMPROVING BUT STILL
SHOWS DIFFERENCES IN TIMING ON THE EASTWARD PACE OF THE SYSTEM.
PREFER SLOWER SOLUTIONS FOR THE GREAT LAKES GIVEN THE CONTINUED HIGH
AMPLITUDE LONG WAVE PATTERN HIGHLIGHTED BY THE FORMIDABLE RIDGE AXIS
AND NOR` EASTER COMBO OFF THE ATLANTIC COAST. SLOWER TIMING WILL
HELP ENSURE A SHORT WAVE TRACK TO OUR WEST AND A WARM OUTCOME FOR
PRECIPITATION TYPE. OUR GOING FORECAST HAS THIS HANDLED WELL WITH
ALL RAIN CENTERED ON TUESDAY IN SE MICHIGAN. THIS IS FOLLOWED BY A
RETURN TO A BLOCKING PATTERN FOR THE SECOND HALF OF THE WEEK BUT
CHAOTIC MODEL DEPICTIONS SUGGEST THE LOCATION OF EVEN THE LARGER
SCALE UPPER AIR FEATURES ARE IN QUESTION.
MARINE...
SMALL CRAFT ADVISORIES WILL REMAIN IN EFFECT FOR OUTER SAGINAW BAY
AROUND TO HARBOR BEACH FOR LINGERING ROUGH WATER DURING THE EARLY
MORNING. A SLOWLY DECREASING DOWNWARD TREND IN WIND AND WAVES WILL
CONTINUE OVER ALL MARINE AREAS AS HIGH PRESSURE BUILDS INTO THE
CENTRAL GREAT LAKES TODAY. MILDER AIR STREAMING INTO THE REGION OVER
THE WEEKEND WILL LEAD TO STABLE PROFILES...AND CORRESPONDING LIGHT
WINDS AND LOW WAVES THROUGH EARLY NEXT WEEK.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....MR
SHORT TERM...MR
LONG TERM....BT
MARINE.......BT
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1138 PM CST FRI DEC 12 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 307 PM CST FRI DEC 12 2014
FOR THE NEXT 36 HOURS...CLOUDS...FOG POTENTIAL AND TEMPERATURES ARE
THE PRIMARY FORECAST CONCERNS. FOR THE OVERNIGHT...THE HRRR AND NAM
VISIBILITY PROGS CONTINUE TO INDICATE A THREAT OF FOG...POSSIBLY
DENSE...THROUGH AT LEAST 15Z CST SATURDAY. THE MODELS ARE SHOWING A
CONTINUED TAP OF BL MOISTURE INTO THE FORECAST AREA WITH LIGHT
SOUTHERLY WIND. AT THIS POINT THE MODELS ARE PROGGING FAR SOUTHWEST
NEBRASKA THROUGH KEITH COUNTY AND NORTHEAST INTO THE WEST CENTRAL
SANDHILLS FOR THE GREATEST POTENTIAL OF DENSE /ADVISORY CRITERIA/
FOG. SIMILAR TO THIS MORNING...WE/RE EXPECTING A THIN LINE OF
ADVISORY CRITERIA FOG TO FORM JUST ALONG THE WESTERN EXTENT OF THE
GREATEST MOISTURE PUSH /FROM SOUTHWEST NEBRASKA INTO THE CENTRAL
SANDHILLS/. SINCE THE EXPECTED ADVISORY CRITERIA FOG TONIGHT WILL
BE FAIRLY LOCALIZED...WILL HOLD OFF ON AN ADVISORY FOR NOW AND WAIT
TO SEE HOW THE TRENDS PLAY OUT. REGARDLESS...THE QUALITY OF
MOISTURE ADVECTION INTO THE AREA SHOULD PROVIDE FOR AREAS OR
WIDESPREAD 1SM FOG /OR LESS/ FOR A GOOD CHUNK OF THE FORECAST
AREA...GENERALLY ALONG AND EAST OF HIGHWAY 61. CEILINGS AND
VISIBILITY IS SHOWN TO IMPROVE BEYOND 15Z SATURDAY FOR MOST
LOCATIONS...HOWEVER BUFR SOUNDINGS EAST OF A KLBF TO KANW LINE KEEP
MOST LOCATIONS UNDER THE INFLUENCE OF STRATUS FOR MUCH OF THE DAY
SATURDAY.
THE GENERAL CONSENSUS SUGGESTS TD/S IN THE LOWER TO MID 40S FOR
LOCATIONS GENERALLY ALONG AND EAST OF A KMCK TO KLBF TO KANW LINE.
INTERESTINGLY...OVER THE PAST TEN YEARS...KLBF HAS NOT RECORDED A
40F OR HIGHER TD/S DURING THE MONTH OF DECEMBER. THESE ANOMALOUSLY
WARM TD/S WILL COMBINE WITH THE PRESENCE OF CLOUDS TO KEEP
TEMPERATURES WARM OVERNIGHT...LOWS WILL RANGE FROM THE LOWER TO MID
30S ACROSS OUR FAR SOUTHWEST...TO THE LOWER TO MID 40S OVER OUR
EAST. THESE PROJECTED VALUES ARE UP TO 10F WARMER THAN WHAT
NUMERICAL GUIDANCE SUGGESTS. HIGHS SATURDAYS WILL BE LIMITED BY THE
PRESENCE OF CLOUDS...BUT WARM YET INTO THE 50S FOR MOST
LOCATIONS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 307 PM CST FRI DEC 12 2014
AS THE UPPER TROUGH COMES ACROSS THE ROCKIES SATURDAY NIGHT...
CYCLOGENESIS RESULTS IN A FAIRLY STRONG STORM SYSTEM DEVELOPING IN
NORTHEAST NEW MEXICO OR SOUTHEAST COLORADO.
AS THE CYCLONE MAKES ITS WAY INTO THE OKLAHOMA PANHANDLE REGION
SUNDAY EVENING...THE MOIST TRAJECTORY TURNS WESTWARD INTO SOUTHWEST
NEBRASKA. MOISTURE TRANSPORT VECTORS IN THE 295-300K LAYER SHOW
THAT. FOR ACTUAL MOISTURE...MIXING RATIOS OF 3-6G/KG CAN BE
EXPECTED. THE LIFT OF THE NEARLY SATURATED AIR REACHES INTO THE
DENDRITIC LAYER BUT THERE IS A WARM LAYER ACCORDING TO THE MEAN
0-2KM TEMPERATURE. SURFACE TEMPERATURES ARE EXPECTED TO BE AT OR A
LITTLE BELOW 0C...SO THE PRECIPITATION TYPE WILL BE SLEET AND/OR
FREEZING RAIN AT LEAST INITIALLY. BETWEEN 00Z AND 06Z...THE MEAN
0-2KM TEMPERATURE DECREASES TO BELOW 0C SO THE CHANGEOVER SHOULD
OCCUR IN THAT TIME WINDOW. THE CYCLONE WILL THEN MAKE ITS WAY INTO
EASTERN NEBRASKA AND EVENTUALLY BECOME AN OPEN TROUGH AS IT MOVES
INTO THE MISSISSIPPI VALLEY. DURING THAT PERIOD...THE NORTHERN
STREAM SYSTEM WILL PROBABLY BECOME THE DOMINANT FEATURE. THIS SHOULD
BRING THE SNOW TO AN END BETWEEN 15Z AND 18Z FOR MOST OF CENTRAL AND
SOUTHWEST NEBRASKA. USING A SNOW/LIQUID RATIO OF 9/1 INITIALLY IT
APPEARS THAT TOTAL ACCUMULATIONS COULD BE AS MUCH AS 6 INCHES IN
NORTH CENTRAL TO NORTHEAST NEBRASKA...THOUGH WE HAVE ONLY MODERATE
CONFIDENCE IN THAT AMOUNT. WITH THE POTENTIAL FOR FREEZING
RAIN...THE IMPACT WILL BE SIGNIFICANT EVEN WHERE THE SNOW TOTALS ARE
3 INCHES OR LESS. WITH THE STRONG POTENTIAL FOR CONVECTION IN
KANSAS...OKLAHOMA AND ARKANSAS...THE STORM MAY TAKE A MORE SOUTHERLY
TRACK. THUS...THE UNCERTAINTY IS STILL QUITE HIGH. IN FACT THE SWATH
OF UNCERTAINTY WITH THE STORM TRACK IS THE WIDTH OF STATE OR A
LITTLE BROADER.
AFTER THE SOUTHERN STREAM SYSTEM PASSES...ANOTHER TROUGH MAY SWING
ACROSS THE REGION AND IT COULD BRING SOME SIGNIFICANT SNOW TO NORTH
CENTRAL AND NORTHEAST NEBRASKA AS IT SWINGS THROUGH SOUTH DAKOTA AND
NORTHERN NEBRASKA. AT THIS TIME...ONLY THE NAM SHOWS THAT
FEATURE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1139 PM CST FRI DEC 12 2014
AT KVTN...MVFR CONDITIONS WILL BECOME IFR BY 09Z AND SHOULD REMAIN
IFR UNTIL BECOMING SCATTERED BY AROUND 19Z. IF STRTUS DOES BECOME
SCATTERED...IFR CEILINGS WILL BE NEARBY...PERSISTING AT KANW
THROUGH THE PERIOD. AT KLBF...CURRENT IFR CEILINGS NEAR OVC009
SHOULD GRADUALLY LOWER TOWARD 12Z TO OVC005. IN ADDITION...FOG AND
DRIZZLE FAVORABLE TO OCCUR...ALTHOUGH VSBY SHOULD RANGE AT OR
ABOVE 4SM. AFTER 16Z...EXPECT P6SM OVC008 THROUGH THE AFTERNOON.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JACOBS
LONG TERM...SPRINGER
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
602 PM CST FRI DEC 12 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 307 PM CST FRI DEC 12 2014
FOR THE NEXT 36 HOURS...CLOUDS...FOG POTENTIAL AND TEMPERATURES ARE
THE PRIMARY FORECAST CONCERNS. FOR THE OVERNIGHT...THE HRRR AND NAM
VISIBILITY PROGS CONTINUE TO INDICATE A THREAT OF FOG...POSSIBLY
DENSE...THROUGH AT LEAST 15Z CST SATURDAY. THE MODELS ARE SHOWING A
CONTINUED TAP OF BL MOISTURE INTO THE FORECAST AREA WITH LIGHT
SOUTHERLY WIND. AT THIS POINT THE MODELS ARE PROGGING FAR SOUTHWEST
NEBRASKA THROUGH KEITH COUNTY AND NORTHEAST INTO THE WEST CENTRAL
SANDHILLS FOR THE GREATEST POTENTIAL OF DENSE /ADVISORY CRITERIA/
FOG. SIMILAR TO THIS MORNING...WE/RE EXPECTING A THIN LINE OF
ADVISORY CRITERIA FOG TO FORM JUST ALONG THE WESTERN EXTENT OF THE
GREATEST MOISTURE PUSH /FROM SOUTHWEST NEBRASKA INTO THE CENTRAL
SANDHILLS/. SINCE THE EXPECTED ADVISORY CRITERIA FOG TONIGHT WILL
BE FAIRLY LOCALIZED...WILL HOLD OFF ON AN ADVISORY FOR NOW AND WAIT
TO SEE HOW THE TRENDS PLAY OUT. REGARDLESS...THE QUALITY OF
MOISTURE ADVECTION INTO THE AREA SHOULD PROVIDE FOR AREAS OR
WIDESPREAD 1SM FOG /OR LESS/ FOR A GOOD CHUNK OF THE FORECAST
AREA...GENERALLY ALONG AND EAST OF HIGHWAY 61. CEILINGS AND
VISIBILITY IS SHOWN TO IMPROVE BEYOND 15Z SATURDAY FOR MOST
LOCATIONS...HOWEVER BUFR SOUNDINGS EAST OF A KLBF TO KANW LINE KEEP
MOST LOCATIONS UNDER THE INFLUENCE OF STRATUS FOR MUCH OF THE DAY
SATURDAY.
THE GENERAL CONSENSUS SUGGESTS TD/S IN THE LOWER TO MID 40S FOR
LOCATIONS GENERALLY ALONG AND EAST OF A KMCK TO KLBF TO KANW LINE.
INTERESTINGLY...OVER THE PAST TEN YEARS...KLBF HAS NOT RECORDED A
40F OR HIGHER TD/S DURING THE MONTH OF DECEMBER. THESE ANOMALOUSLY
WARM TD/S WILL COMBINE WITH THE PRESENCE OF CLOUDS TO KEEP
TEMPERATURES WARM OVERNIGHT...LOWS WILL RANGE FROM THE LOWER TO MID
30S ACROSS OUR FAR SOUTHWEST...TO THE LOWER TO MID 40S OVER OUR
EAST. THESE PROJECTED VALUES ARE UP TO 10F WARMER THAN WHAT
NUMERICAL GUIDANCE SUGGESTS. HIGHS SATURDAYS WILL BE LIMITED BY THE
PRESENCE OF CLOUDS...BUT WARM YET INTO THE 50S FOR MOST
LOCATIONS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 307 PM CST FRI DEC 12 2014
AS THE UPPER TROUGH COMES ACROSS THE ROCKIES SATURDAY NIGHT...
CYCLOGENESIS RESULTS IN A FAIRLY STRONG STORM SYSTEM DEVELOPING IN
NORTHEAST NEW MEXICO OR SOUTHEAST COLORADO.
AS THE CYCLONE MAKES ITS WAY INTO THE OKLAHOMA PANHANDLE REGION
SUNDAY EVENING...THE MOIST TRAJECTORY TURNS WESTWARD INTO SOUTHWEST
NEBRASKA. MOISTURE TRANSPORT VECTORS IN THE 295-300K LAYER SHOW
THAT. FOR ACTUAL MOISTURE...MIXING RATIOS OF 3-6G/KG CAN BE
EXPECTED. THE LIFT OF THE NEARLY SATURATED AIR REACHES INTO THE
DENDRITIC LAYER BUT THERE IS A WARM LAYER ACCORDING TO THE MEAN
0-2KM TEMPERATURE. SURFACE TEMPERATURES ARE EXPECTED TO BE AT OR A
LITTLE BELOW 0C...SO THE PRECIPITATION TYPE WILL BE SLEET AND/OR
FREEZING RAIN AT LEAST INITIALLY. BETWEEN 00Z AND 06Z...THE MEAN
0-2KM TEMPERATURE DECREASES TO BELOW 0C SO THE CHANGEOVER SHOULD
OCCUR IN THAT TIME WINDOW. THE CYCLONE WILL THEN MAKE ITS WAY INTO
EASTERN NEBRASKA AND EVENTUALLY BECOME AN OPEN TROUGH AS IT MOVES
INTO THE MISSISSIPPI VALLEY. DURING THAT PERIOD...THE NORTHERN
STREAM SYSTEM WILL PROBABLY BECOME THE DOMINANT FEATURE. THIS SHOULD
BRING THE SNOW TO AN END BETWEEN 15Z AND 18Z FOR MOST OF CENTRAL AND
SOUTHWEST NEBRASKA. USING A SNOW/LIQUID RATIO OF 9/1 INITIALLY IT
APPEARS THAT TOTAL ACCUMULATIONS COULD BE AS MUCH AS 6 INCHES IN
NORTH CENTRAL TO NORTHEAST NEBRASKA...THOUGH WE HAVE ONLY MODERATE
CONFIDENCE IN THAT AMOUNT. WITH THE POTENTIAL FOR FREEZING
RAIN...THE IMPACT WILL BE SIGNIFICANT EVEN WHERE THE SNOW TOTALS ARE
3 INCHES OR LESS. WITH THE STRONG POTENTIAL FOR CONVECTION IN
KANSAS...OKLAHOMA AND ARKANSAS...THE STORM MAY TAKE A MORE SOUTHERLY
TRACK. THUS...THE UNCERTAINTY IS STILL QUITE HIGH. IN FACT THE SWATH
OF UNCERTAINTY WITH THE STORM TRACK IS THE WIDTH OF STATE OR A
LITTLE BROADER.
AFTER THE SOUTHERN STREAM SYSTEM PASSES...ANOTHER TROUGH MAY SWING
ACROSS THE REGION AND IT COULD BRING SOME SIGNIFICANT SNOW TO NORTH
CENTRAL AND NORTHEAST NEBRASKA AS IT SWINGS THROUGH SOUTH DAKOTA AND
NORTHERN NEBRASKA. AT THIS TIME...ONLY THE NAM SHOWS THAT
FEATURE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 602 PM CST FRI DEC 12 2014
MVFR CONDITIONS WILL BECOME IFR THIS EVENING AND REMAIN SO FOR THE
REMAINDER OF THE PERIOD FOR KLBF...KIML...AND ALSO KBBW. AT
KVTN...CURRENT VFR SHOULD BECOME MVFR BY AROUND 03Z...THEN IFR
AFTER 05Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JACOBS
LONG TERM...SPRINGER
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
308 PM CST FRI DEC 12 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 307 PM CST FRI DEC 12 2014
FOR THE NEXT 36 HOURS...CLOUDS...FOG POTENTIAL AND TEMPERATURES ARE
THE PRIMARY FORECAST CONCERNS. FOR THE OVERNIGHT...THE HRRR AND NAM
VISIBILITY PROGS CONTINUE TO INDICATE A THREAT OF FOG...POSSIBLY
DENSE...THROUGH AT LEAST 15Z CST SATURDAY. THE MODELS ARE SHOWING A
CONTINUED TAP OF BL MOISTURE INTO THE FORECAST AREA WITH LIGHT
SOUTHERLY WIND. AT THIS POINT THE MODELS ARE PROGGING FAR SOUTHWEST
NEBRASKA THROUGH KEITH COUNTY AND NORTHEAST INTO THE WEST CENTRAL
SANDHILLS FOR THE GREATEST POTENTIAL OF DENSE /ADVISORY CRITERIA/
FOG. SIMILAR TO THIS MORNING...WE/RE EXPECTING A THIN LINE OF
ADVISORY CRITERIA FOG TO FORM JUST ALONG THE WESTERN EXTENT OF THE
GREATEST MOISTURE PUSH /FROM SOUTHWEST NEBRASKA INTO THE CENTRAL
SANDHILLS/. SINCE THE EXPECTED ADVISORY CRITERIA FOG TONIGHT WILL
BE FAIRLY LOCALIZED...WILL HOLD OFF ON AN ADVISORY FOR NOW AND WAIT
TO SEE HOW THE TRENDS PLAY OUT. REGARDLESS...THE QUALITY OF
MOISTURE ADVECTION INTO THE AREA SHOULD PROVIDE FOR AREAS OR
WIDESPREAD 1SM FOG /OR LESS/ FOR A GOOD CHUNK OF THE FORECAST
AREA...GENERALLY ALONG AND EAST OF HIGHWAY 61. CEILINGS AND
VISIBILITY IS SHOWN TO IMPROVE BEYOND 15Z SATURDAY FOR MOST
LOCATIONS...HOWEVER BUFR SOUNDINGS EAST OF A KLBF TO KANW LINE KEEP
MOST LOCATIONS UNDER THE INFLUENCE OF STRATUS FOR MUCH OF THE DAY
SATURDAY.
THE GENERAL CONSENSUS SUGGESTS TD/S IN THE LOWER TO MID 40S FOR
LOCATIONS GENERALLY ALONG AND EAST OF A KMCK TO KLBF TO KANW LINE.
INTERESTINGLY...OVER THE PAST TEN YEARS...KLBF HAS NOT RECORDED A
40F OR HIGHER TD/S DURING THE MONTH OF DECEMBER. THESE ANOMALOUSLY
WARM TD/S WILL COMBINE WITH THE PRESENCE OF CLOUDS TO KEEP
TEMPERATURES WARM OVERNIGHT...LOWS WILL RANGE FROM THE LOWER TO MID
30S ACROSS OUR FAR SOUTHWEST...TO THE LOWER TO MID 40S OVER OUR
EAST. THESE PROJECTED VALUES ARE UP TO 10F WARMER THAN WHAT
NUMERICAL GUIDANCE SUGGESTS. HIGHS SATURDAYS WILL BE LIMITED BY THE
PRESENCE OF CLOUDS...BUT WARM YET INTO THE 50S FOR MOST
LOCATIONS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 307 PM CST FRI DEC 12 2014
AS THE UPPER TROUGH COMES ACROSS THE ROCKIES SATURDAY NIGHT...
CYCLOGENESIS RESULTS IN A FAIRLY STRONG STORM SYSTEM DEVELOPING IN
NORTHEAST NEW MEXICO OR SOUTHEAST COLORADO.
AS THE CYCLONE MAKES ITS WAY INTO THE OKLAHOMA PANHANDLE REGION
SUNDAY EVENING...THE MOIST TRAJECTORY TURNS WESTWARD INTO SOUTHWEST
NEBRASKA. MOISTURE TRANSPORT VECTORS IN THE 295-300K LAYER SHOW
THAT. FOR ACTUAL MOISTURE...MIXING RATIOS OF 3-6G/KG CAN BE
EXPECTED. THE LIFT OF THE NEARLY SATURATED AIR REACHES INTO THE
DENDRITIC LAYER BUT THERE IS A WARM LAYER ACCORDING TO THE MEAN
0-2KM TEMPERATURE. SURFACE TEMPERATURES ARE EXPECTED TO BE AT OR A
LITTLE BELOW 0C...SO THE PRECIPITATION TYPE WILL BE SLEET AND/OR
FREEZING RAIN AT LEAST INITIALLY. BETWEEN 00Z AND 06Z...THE MEAN
0-2KM TEMPERATURE DECREASES TO BELOW 0C SO THE CHANGEOVER SHOULD
OCCUR IN THAT TIME WINDOW. THE CYCLONE WILL THEN MAKE ITS WAY INTO
EASTERN NEBRASKA AND EVENTUALLY BECOME AN OPEN TROUGH AS IT MOVES
INTO THE MISSISSIPPI VALLEY. DURING THAT PERIOD...THE NORTHERN
STREAM SYSTEM WILL PROBABLY BECOME THE DOMINANT FEATURE. THIS SHOULD
BRING THE SNOW TO AN END BETWEEN 15Z AND 18Z FOR MOST OF CENTRAL AND
SOUTHWEST NEBRASKA. USING A SNOW/LIQUID RATIO OF 9/1 INITIALLY IT
APPEARS THAT TOTAL ACCUMULATIONS COULD BE AS MUCH AS 6 INCHES IN
NORTH CENTRAL TO NORTHEAST NEBRASKA...THOUGH WE HAVE ONLY MODERATE
CONFIDENCE IN THAT AMOUNT. WITH THE POTENTIAL FOR FREEZING
RAIN...THE IMPACT WILL BE SIGNIFICANT EVEN WHERE THE SNOW TOTALS ARE
3 INCHES OR LESS. WITH THE STRONG POTENTIAL FOR CONVECTION IN
KANSAS...OKLAHOMA AND ARKANSAS...THE STORM MAY TAKE A MORE SOUTHERLY
TRACK. THUS...THE UNCERTAINTY IS STILL QUITE HIGH. IN FACT THE SWATH
OF UNCERTAINTY WITH THE STORM TRACK IS THE WIDTH OF STATE OR A
LITTLE BROADER.
AFTER THE SOUTHERN STREAM SYSTEM PASSES...ANOTHER TROUGH MAY SWING
ACROSS THE REGION AND IT COULD BRING SOME SIGNIFICANT SNOW TO NORTH
CENTRAL AND NORTHEAST NEBRASKA AS IT SWINGS THROUGH SOUTH DAKOTA AND
NORTHERN NEBRASKA. AT THIS TIME...ONLY THE NAM SHOWS THAT
FEATURE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1122 AM CST FRI DEC 12 2014
IFR CONDITIONS ACROSS PARTS OF SOUTHWEST NEBRASKA...INCLUDING
KLBF...WILL SLOWLY LIFT EARLY THIS AFTERNOON AS STRATUS BREAKS UP.
THERE WILL BE A PERIOD OF VFR FOR WESTERN AND NORTH CENTRAL NEBRASKA
THIS AFTERNOON AND EARLY EVENING BEFORE FOG AND STRATUS RETURN.
CONFIDENCE IS HIGH ON THE RECURRENCE OF IFR...ESPECIALLY FOR
SOUTHWEST AND CENTRAL NEBRASKA. LIFR CIGS ARE LIKELY FOR
KLBF...KIML...AND KBBW...BUT ALSO INCLUDED KVTN IN LIFR AS THAT
TERMINAL WILL PROBABLY BE ON THE EDGE OF THE THICKEST FOG AND LOWEST
CEILINGS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JACOBS
LONG TERM...SPRINGER
AVIATION...DS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1132 AM CST FRI DEC 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 355 AM CST FRI DEC 12 2014
LARGE SCALE PATTERN IS AMPLIFYING. A POSITIVELY TILTED RIDGE
STRETCHES FROM THE SOUTHERN ROCKIES INTO THE NORTHERN PLAINS AS A
STRONG TROUGH MOVES ON SHORE ALONG THE WEST COAST OF THE UNITED
STATES. AT THE SURFACE...WE REMAIN ON THE BACK SIDE OF HIGH PRESSURE
CENTERED OVER THE OHIO VALLEY AS WE ARE SOCKED IN WITH STRATUS AND
SOME FOG. THE EDGE OF THE STRATUS IS WELL WEST OF THE CWA. BECAUSE
THE EDGE OF THE STRATUS IS SO FAR WEST...I HAVE CANCELLED MOST OF
OUR FOG ADVISORY...RELEGATED TO OUR 3 FARTHEST WEST COUNTIES...AND
THIS MAY IN ITSELF BE A VERY CHEAP FOG ADVISORY...WHERE IT IS
STARTING TO LOOK MORE DOUBTFUL THAT EVEN THESE LOCATIONS WILL HAVE
DENSE FOG. WE ARE ACTUALLY GETTING LOWER VISIBILITY IN OUR
SOUTH...AS MOISTURE ADVECTION FROM THE SOUTH OCCURS. THE CLOSEST
DENSE FOG IS IN IMPERIAL AND GOODLAND...STILL A FAIR DISTANCE AWAY.
THE RUC SEEMS TO HAVE A DECENT HANDLE ON CURRENT TEMPERATURES AND
DEWPOINTS AND HAVE GONE WITH THIS MODEL FOR THE MOST PART INTO THE
AFTERNOON. I WENT CLOSER TO THE ADJECEBC SOLUTION FOR LOWS
TONIGHT...CONSIDERING ITS STRONGER SHOWING RECENTLY...ALTHOUGH I DID
BUMP UP TEMPERATURES A BIT MORE THAN WHAT THIS SOLUTION ORIGINALLY
HAD IN THE SOUTHEASTERN CWA. WE SHOULD REMAIN SOCKED WITHIN STRATUS
FOR THE ENTIRE SHORT TERM. MORE DRIZZLE AND FOG IS IN THE FORECAST
TONIGHT. MOST MODEL SOLUTIONS REVEAL LIGHT QPF TONIGHT...EVEN THE
ECMWF. THE PROBLEM WILL BE WITH THE DEPTH OF BOUNDARY LAYER
MOISTURE. THIS IS A LIMITING FACTOR...BUT WITH SO MUCH AGREEMENT
AMONG MODELS WITH LIGHT QPF...I AM INCLINED TO KEEP IN THE
DRIZZLE...BUT INTRODUCED IT A BIT LATER...IN THE MID-EVENING. FOG
COULD BE MORE OF AN ISSUE ALONG THE WESTERN FRINGE OF THE
STRATUS...BUT ONCE AGAIN...IT LOOKS LIKE THAT WILL BE WEST OF
THE CWA FOR THE MOST PART.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 355 AM CST FRI DEC 12 2014
PATTERN: THE FLOW WILL BE VERY COMPLEX AND AT TIMES HIGHLY AMPLIFIED
THE NEXT SEVERAL DAYS...BUT THE MULTI-DAY ENSEMBLE MEANS ARE IN
DECENT AGREEMENT ON LONGWAVE RIDGING OVER THE CNTRL/ERN USA WITH
ABOVE NORMAL HEIGHTS OVER CANADA...AND A LONGWAVE TROF OVER THE E
PAC. THIS TROF WILL DELIVER THE BEST OPPORTUNITY WE HAVE SEEN FOR
MUCH-NEEDED MEANINGFUL PRECIP SINCE OCT 22ND. SOME OF IT COULD BE OF
THE WINTRY VARIETY.
HIGHLY RECOMMEND THE 1ST PARAGRAPH OF THE MODEL DIAGNOSTIC DISC
/PMDHMD/ FROM WPC. IT HAS AN EXCELLENT OVERVIEW OF MODEL TRENDS FOR
THE SYSTEM SUN-MON.
ALOFT: HIGH PRES WILL SLOWLY PROGRESS INTO THE ERN USA SAT-SUN AS
THE TROF CURRENTLY MOVING ONSHORE INTO CA HEADS E THRU THE DESERT SW
AND EJECTS NE ACROSS KS SUN-MON. A RIDGE WILL BUILD BACK INTO THE
REGION TUE-THU WITH ANOTHER TROF MOVING INTO THE DESERT SW.
SURFACE: HIGH PRES WILL BE OVER THE ERN USA SAT WITH GRADUAL
EASTWARD PROGRESSION SUN-MON. MEANWHILE...THE COLD FRONT MAKING ITS
WAY THRU THE INTERMOUNTAIN W WILL MOVE THRU HERE SUN WITH THE LEE-
SIDE LOW OVER CO MERGING WITH THE FRONT...MOVING ACROSS KS SUN NIGHT
AND INTO IA MON. CANADIAN HIGH PRES BUILDS IN TUE AND SINKS INTO THE
NRN PLAINS WED-THU.
THE DAILY DETAILS...
USED CONSENSUS OF MODEL 2M TEMPS FOR HIGHS/LOWS FOR SAT-SUN OR VERY
CLOSE TO IT. WE CONT TO FCST RECORD WARM LOW TEMPS BOTH SAT AND SUN.
FOR SUN`S RECORDS TO BE BROKEN...TEMPS MUST STAY ABOVE THE RECORDS
THRU 1159 PM AND WE WILL BE COLD ADVECTING SUN EVE.
RECORD WARM LOWS
SAT 12/13 SUN 12/14
GRI 37 - 1896 39 - 1896
HSI 36 - 1921 36 - 1928
WE HAVE HIGH CONFIDENCE SAT`S RECORDS WILL BE BROKEN AND MEDIUM
CONFIDENCE FOR SUN`S.
SAT: NO SUBSTANTIVE CHANGE FROM THU OR FRI. CLOUDY WITH AM FOG/MIST.
AM NOT CONVINCED ON DRZL POTENTIAL. MOISTURE DEPTH CASTS DOUBT SO
DRZL WAS DOWNGRADED TO JUST A "CHANCE".
SUN: LATE DAY COLD FRONTAL PASSAGE. ANOTHER CLOUDY START WITH AM
FOG/MIST. AN FGEN-DRIVEN COMMAHEAD BAND OF RAIN WILL DEVELOP OVER KS
AND LIFT NORTHWARD PRIMARILY IN THE AFTERNOON-EVENING HRS. BOTH THE
EC/GFS INDICATE SHOWALTER AND LIFTED INDICES TURNING SLIGHTLY
NEGATIVE. SO THUNDER IS NOW IN THE FCST FOR N-CNTRL KS TO COVER
THIS POSSIBILITY.
SUN NIGHT: IT`S A RACE TO SEE HOW FAST THE COLD AIR CAN WRAP INTO
THE COMMAHEAD AND CHANGE THE RAIN TO SNOW BEFORE PRECIP ENDS. LOTS
OF UNCERTAINTY REMAINS IN THIS TIME FRAME. SUGGEST EVERYONE
INTERESTED IN THIS POTENTIAL CONT TO MONITOR LATER FCSTS AND PREPARE
FOR PLOWABLE SNOW POSSIBILITY. HIGHEST PROBABLY IS CURRENTLY N AND W
OF THE TRI-CITIES.
FOR NOW MAINTAINED CONTINUITY WITH PREVIOUS FCST WITH RAIN MIXING
WITH AND CHANGING TO SNOW EXCEPT THE SE FRINGE OF THE FCST AREA...
ROUGHLY S OF A LINE FROM OSBORNE KS-YORK NE.
MON: BLUSTERY AND COLDER. POSSIBLY A LITTLE LEFTOVER LIGHT SNOW AS
THE LOW DEPARTS WRN IA INTO THE UPPER MIDWEST.
TUE: DRY BUT LOTS OF UNCERTAINTY ON TEMPS/CLOUD COVER. EC/GFS CROSS
SECTIONS SUGGEST A PERIOD OF SUBSTANTIAL MID-HIGH CLOUDINESS UNDER
A STRONG 110KT JET.
WED: DRY AND PROBABLY A LOT OF CLOUDS.
WED NIGHT-THU: WE CURRENTLY HAVE A LOW CHANCE OF RAIN/SNOW BUT IT
LOOKS DOUBTFUL BASED ON THE 00Z EC ENSEMBLE MEAN WHICH SUGGESTS THIS
NEXT DESERT SW SYSTEM REMAINS SUPPRESSED S OF THE FCST AREA.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1123 AM CST FRI DEC 12 2014
EXPECTING ANOTHER ROUND OF LESS THAN IDEAL CONDITIONS AT BOTH
TERMINALS FOR THIS TAF PERIOD...THANKS TO NOT MUCH CHANGE WITH THE
OVERALL PATTERN. CONFIDENCE IN HOW MUCH THINGS WILL IMPROVE THIS
AFTERNOON...ESP WITH CEILINGS...IS NOT HIGH...AND KEPT THE
MID/LATE AFTERNOON HOURS MFVR. WILL SEE HOW THINGS TREND IN NEXT
COUPLE HOURS...AS THERE ARE BATCHES OF BOTH HIGHER AND LOWER THAN
FORECAST CEILINGS IN THE AREA. EXPECTING THINGS TO DETERIORATE
AGAIN THIS EVENING/OVERNIGHT...AS MODELS SHOW THE LOWER LEVEL
STRATUS/FOG/DRIZZLE DEVELOPING ONCE AGAIN. KEPT THINGS SIMILAR TO
INHERITED TAF AND WHAT BOTH SITES SAW THIS MORNING. SIMILAR TO
TODAY...CONDITIONS SHOULD START TO IMPROVE IN THE LATER PORTIONS
OF THE TAF. AS FAR AS WINDS GO...WITH NO OVERALL CHANGE IN THE
SURFACE PATTERN...THE SOUTHERLY WINDS WILL REMAIN IN PLACE THROUGH
THE PERIOD.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...ADP
SHORT TERM...HEINLEIN
LONG TERM...HALBLAUB
AVIATION...ADP
AREA FORECAST DISCUSSION
NWS HASTINGS NE
953 AM CST FRI DEC 12 2014
.UPDATE...
ISSUED AT 950 AM CST FRI DEC 12 2014
WHILE AREAS OF FOG LINGER ACROSS THE AREA THIS
MORNING...VISIBILITIES HAVE GRADUALLY IMPROVED...SO THE DENSE FOG
ADVISORY WILL BE ALLOWED TO EXPIRE. OTHERWISE...AT THIS POINT NO
NOTABLE CHANGES WERE MADE TO THE FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 355 AM CST FRI DEC 12 2014
LARGE SCALE PATTERN IS AMPLIFYING. A POSITIVELY TILTED RIDGE
STRETCHES FROM THE SOUTHERN ROCKIES INTO THE NORTHERN PLAINS AS A
STRONG TROUGH MOVES ON SHORE ALONG THE WEST COAST OF THE UNITED
STATES. AT THE SURFACE...WE REMAIN ON THE BACK SIDE OF HIGH PRESSURE
CENTERED OVER THE OHIO VALLEY AS WE ARE SOCKED IN WITH STRATUS AND
SOME FOG. THE EDGE OF THE STRATUS IS WELL WEST OF THE CWA. BECAUSE
THE EDGE OF THE STRATUS IS SO FAR WEST...I HAVE CANCELLED MOST OF
OUR FOG ADVISORY...RELEGATED TO OUR 3 FARTHEST WEST COUNTIES...AND
THIS MAY IN ITSELF BE A VERY CHEAP FOG ADVISORY...WHERE IT IS
STARTING TO LOOK MORE DOUBTFUL THAT EVEN THESE LOCATIONS WILL HAVE
DENSE FOG. WE ARE ACTUALLY GETTING LOWER VISIBILITY IN OUR
SOUTH...AS MOISTURE ADVECTION FROM THE SOUTH OCCURS. THE CLOSEST
DENSE FOG IS IN IMPERIAL AND GOODLAND...STILL A FAIR DISTANCE AWAY.
THE RUC SEEMS TO HAVE A DECENT HANDLE ON CURRENT TEMPERATURES AND
DEWPOINTS AND HAVE GONE WITH THIS MODEL FOR THE MOST PART INTO THE
AFTERNOON. I WENT CLOSER TO THE ADJECEBC SOLUTION FOR LOWS
TONIGHT...CONSIDERING ITS STRONGER SHOWING RECENTLY...ALTHOUGH I DID
BUMP UP TEMPERATURES A BIT MORE THAN WHAT THIS SOLUTION ORIGINALLY
HAD IN THE SOUTHEASTERN CWA. WE SHOULD REMAIN SOCKED WITHIN STRATUS
FOR THE ENTIRE SHORT TERM. MORE DRIZZLE AND FOG IS IN THE FORECAST
TONIGHT. MOST MODEL SOLUTIONS REVEAL LIGHT QPF TONIGHT...EVEN THE
ECMWF. THE PROBLEM WILL BE WITH THE DEPTH OF BOUNDARY LAYER
MOISTURE. THIS IS A LIMITING FACTOR...BUT WITH SO MUCH AGREEMENT
AMONG MODELS WITH LIGHT QPF...I AM INCLINED TO KEEP IN THE
DRIZZLE...BUT INTRODUCED IT A BIT LATER...IN THE MID-EVENING. FOG
COULD BE MORE OF AN ISSUE ALONG THE WESTERN FRINGE OF THE
STRATUS...BUT ONCE AGAIN...IT LOOKS LIKE THAT WILL BE WEST OF
THE CWA FOR THE MOST PART.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 355 AM CST FRI DEC 12 2014
PATTERN: THE FLOW WILL BE VERY COMPLEX AND AT TIMES HIGHLY AMPLIFIED
THE NEXT SEVERAL DAYS...BUT THE MULTI-DAY ENSEMBLE MEANS ARE IN
DECENT AGREEMENT ON LONGWAVE RIDGING OVER THE CNTRL/ERN USA WITH
ABOVE NORMAL HEIGHTS OVER CANADA...AND A LONGWAVE TROF OVER THE E
PAC. THIS TROF WILL DELIVER THE BEST OPPORTUNITY WE HAVE SEEN FOR
MUCH-NEEDED MEANINGFUL PRECIP SINCE OCT 22ND. SOME OF IT COULD BE OF
THE WINTRY VARIETY.
HIGHLY RECOMMEND THE 1ST PARAGRAPH OF THE MODEL DIAGNOSTIC DISC
/PMDHMD/ FROM WPC. IT HAS AN EXCELLENT OVERVIEW OF MODEL TRENDS FOR
THE SYSTEM SUN-MON.
ALOFT: HIGH PRES WILL SLOWLY PROGRESS INTO THE ERN USA SAT-SUN AS
THE TROF CURRENTLY MOVING ONSHORE INTO CA HEADS E THRU THE DESERT SW
AND EJECTS NE ACROSS KS SUN-MON. A RIDGE WILL BUILD BACK INTO THE
REGION TUE-THU WITH ANOTHER TROF MOVING INTO THE DESERT SW.
SURFACE: HIGH PRES WILL BE OVER THE ERN USA SAT WITH GRADUAL
EASTWARD PROGRESSION SUN-MON. MEANWHILE...THE COLD FRONT MAKING ITS
WAY THRU THE INTERMOUNTAIN W WILL MOVE THRU HERE SUN WITH THE LEE-
SIDE LOW OVER CO MERGING WITH THE FRONT...MOVING ACROSS KS SUN NIGHT
AND INTO IA MON. CANADIAN HIGH PRES BUILDS IN TUE AND SINKS INTO THE
NRN PLAINS WED-THU.
THE DAILY DETAILS...
USED CONSENSUS OF MODEL 2M TEMPS FOR HIGHS/LOWS FOR SAT-SUN OR VERY
CLOSE TO IT. WE CONT TO FCST RECORD WARM LOW TEMPS BOTH SAT AND SUN.
FOR SUN`S RECORDS TO BE BROKEN...TEMPS MUST STAY ABOVE THE RECORDS
THRU 1159 PM AND WE WILL BE COLD ADVECTING SUN EVE.
RECORD WARM LOWS
SAT 12/13 SUN 12/14
GRI 37 - 1896 39 - 1896
HSI 36 - 1921 36 - 1928
WE HAVE HIGH CONFIDENCE SAT`S RECORDS WILL BE BROKEN AND MEDIUM
CONFIDENCE FOR SUN`S.
SAT: NO SUBSTANTIVE CHANGE FROM THU OR FRI. CLOUDY WITH AM FOG/MIST.
AM NOT CONVINCED ON DRZL POTENTIAL. MOISTURE DEPTH CASTS DOUBT SO
DRZL WAS DOWNGRADED TO JUST A "CHANCE".
SUN: LATE DAY COLD FRONTAL PASSAGE. ANOTHER CLOUDY START WITH AM
FOG/MIST. AN FGEN-DRIVEN COMMAHEAD BAND OF RAIN WILL DEVELOP OVER KS
AND LIFT NORTHWARD PRIMARILY IN THE AFTERNOON-EVENING HRS. BOTH THE
EC/GFS INDICATE SHOWALTER AND LIFTED INDICES TURNING SLIGHTLY
NEGATIVE. SO THUNDER IS NOW IN THE FCST FOR N-CNTRL KS TO COVER
THIS POSSIBILITY.
SUN NIGHT: IT`S A RACE TO SEE HOW FAST THE COLD AIR CAN WRAP INTO
THE COMMAHEAD AND CHANGE THE RAIN TO SNOW BEFORE PRECIP ENDS. LOTS
OF UNCERTAINTY REMAINS IN THIS TIME FRAME. SUGGEST EVERYONE
INTERESTED IN THIS POTENTIAL CONT TO MONITOR LATER FCSTS AND PREPARE
FOR PLOWABLE SNOW POSSIBILITY. HIGHEST PROBABLY IS CURRENTLY N AND W
OF THE TRI-CITIES.
FOR NOW MAINTAINED CONTINUITY WITH PREVIOUS FCST WITH RAIN MIXING
WITH AND CHANGING TO SNOW EXCEPT THE SE FRINGE OF THE FCST AREA...
ROUGHLY S OF A LINE FROM OSBORNE KS-YORK NE.
MON: BLUSTERY AND COLDER. POSSIBLY A LITTLE LEFTOVER LIGHT SNOW AS
THE LOW DEPARTS WRN IA INTO THE UPPER MIDWEST.
TUE: DRY BUT LOTS OF UNCERTAINTY ON TEMPS/CLOUD COVER. EC/GFS CROSS
SECTIONS SUGGEST A PERIOD OF SUBSTANTIAL MID-HIGH CLOUDINESS UNDER
A STRONG 110KT JET.
WED: DRY AND PROBABLY A LOT OF CLOUDS.
WED NIGHT-THU: WE CURRENTLY HAVE A LOW CHANCE OF RAIN/SNOW BUT IT
LOOKS DOUBTFUL BASED ON THE 00Z EC ENSEMBLE MEAN WHICH SUGGESTS THIS
NEXT DESERT SW SYSTEM REMAINS SUPPRESSED S OF THE FCST AREA.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 544 AM CST FRI DEC 12 2014
CEILING WILL BE TOUGH TO CALL THIS MORNING AS THEY TEETER ON THE
LOW END OF IFR. VISIBILITY IS ALSO ON THE EDGE OF CATEGORIES. AT
GRI...TEETERING BETWEEN VFR AND MVFR THIS MORNING...WHILE EAR WILL
BE ON THE CUSP MVFR/IFR. THERE COULD ALSO BE SOME VERY LIGHT
DRIZZLE THIS MORNING AS WELL. MORE VISIBILITY RESTRICTION IS
EXPECTED TONIGHT ALONG WITH SOME DRIZZLE. WE COULD GET SOME FOG
DURING THE OVERNIGHT...TOWARD THE END OF THE FORECAST.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...ADP
SHORT TERM...HEINLEIN
LONG TERM...HALBLAUB
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
552 AM CST FRI DEC 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 355 AM CST FRI DEC 12 2014
LARGE SCALE PATTERN IS AMPLIFYING. A POSITIVELY TILTED RIDGE
STRETCHES FROM THE SOUTHERN ROCKIES INTO THE NORTHERN PLAINS AS A
STRONG TROUGH MOVES ON SHORE ALONG THE WEST COAST OF THE UNITED
STATES. AT THE SURFACE...WE REMAIN ON THE BACK SIDE OF HIGH PRESSURE
CENTERED OVER THE OHIO VALLEY AS WE ARE SOCKED IN WITH STRATUS AND
SOME FOG. THE EDGE OF THE STRATUS IS WELL WEST OF THE CWA. BECAUSE
THE EDGE OF THE STRATUS IS SO FAR WEST...I HAVE CANCELLED MOST OF
OUR FOG ADVISORY...RELEGATED TO OUR 3 FARTHEST WEST COUNTIES...AND
THIS MAY IN ITSELF BE A VERY CHEAP FOG ADVISORY...WHERE IT IS
STARTING TO LOOK MORE DOUBTFUL THAT EVEN THESE LOCATIONS WILL HAVE
DENSE FOG. WE ARE ACTUALLY GETTING LOWER VISIBILITY IN OUR
SOUTH...AS MOISTURE ADVECTION FROM THE SOUTH OCCURS. THE CLOSEST
DENSE FOG IS IN IMPERIAL AND GOODLAND...STILL A FAIR DISTANCE AWAY.
THE RUC SEEMS TO HAVE A DECENT HANDLE ON CURRENT TEMPERATURES AND
DEWPOINTS AND HAVE GONE WITH THIS MODEL FOR THE MOST PART INTO THE
AFTERNOON. I WENT CLOSER TO THE ADJECEBC SOLUTION FOR LOWS
TONIGHT...CONSIDERING ITS STRONGER SHOWING RECENTLY...ALTHOUGH I DID
BUMP UP TEMPERATURES A BIT MORE THAN WHAT THIS SOLUTION ORIGINALLY
HAD IN THE SOUTHEASTERN CWA. WE SHOULD REMAIN SOCKED WITHIN STRATUS
FOR THE ENTIRE SHORT TERM. MORE DRIZZLE AND FOG IS IN THE FORECAST
TONIGHT. MOST MODEL SOLUTIONS REVEAL LIGHT QPF TONIGHT...EVEN THE
ECMWF. THE PROBLEM WILL BE WITH THE DEPTH OF BOUNDARY LAYER
MOISTURE. THIS IS A LIMITING FACTOR...BUT WITH SO MUCH AGREEMENT
AMONG MODELS WITH LIGHT QPF...I AM INCLINED TO KEEP IN THE
DRIZZLE...BUT INTRODUCED IT A BIT LATER...IN THE MID-EVENING. FOG
COULD BE MORE OF AN ISSUE ALONG THE WESTERN FRINGE OF THE
STRATUS...BUT ONCE AGAIN...IT LOOKS LIKE THAT WILL BE WEST OF
THE CWA FOR THE MOST PART.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 355 AM CST FRI DEC 12 2014
PATTERN: THE FLOW WILL BE VERY COMPLEX AND AT TIMES HIGHLY AMPLIFIED
THE NEXT SEVERAL DAYS...BUT THE MULTI-DAY ENSEMBLE MEANS ARE IN
DECENT AGREEMENT ON LONGWAVE RIDGING OVER THE CNTRL/ERN USA WITH
ABOVE NORMAL HEIGHTS OVER CANADA...AND A LONGWAVE TROF OVER THE E
PAC. THIS TROF WILL DELIVER THE BEST OPPORTUNITY WE HAVE SEEN FOR
MUCH-NEEDED MEANINGFUL PRECIP SINCE OCT 22ND. SOME OF IT COULD BE OF
THE WINTRY VARIETY.
HIGHLY RECOMMEND THE 1ST PARAGRAPH OF THE MODEL DIAGNOSTIC DISC
/PMDHMD/ FROM WPC. IT HAS AN EXCELLENT OVERVIEW OF MODEL TRENDS FOR
THE SYSTEM SUN-MON.
ALOFT: HIGH PRES WILL SLOWLY PROGRESS INTO THE ERN USA SAT-SUN AS
THE TROF CURRENTLY MOVING ONSHORE INTO CA HEADS E THRU THE DESERT SW
AND EJECTS NE ACROSS KS SUN-MON. A RIDGE WILL BUILD BACK INTO THE
REGION TUE-THU WITH ANOTHER TROF MOVING INTO THE DESERT SW.
SURFACE: HIGH PRES WILL BE OVER THE ERN USA SAT WITH GRADUAL
EASTWARD PROGRESSION SUN-MON. MEANWHILE...THE COLD FRONT MAKING ITS
WAY THRU THE INTERMOUNTAIN W WILL MOVE THRU HERE SUN WITH THE LEE-
SIDE LOW OVER CO MERGING WITH THE FRONT...MOVING ACROSS KS SUN NIGHT
AND INTO IA MON. CANADIAN HIGH PRES BUILDS IN TUE AND SINKS INTO THE
NRN PLAINS WED-THU.
THE DAILY DETAILS...
USED CONSENSUS OF MODEL 2M TEMPS FOR HIGHS/LOWS FOR SAT-SUN OR VERY
CLOSE TO IT. WE CONT TO FCST RECORD WARM LOW TEMPS BOTH SAT AND SUN.
FOR SUN`S RECORDS TO BE BROKEN...TEMPS MUST STAY ABOVE THE RECORDS
THRU 1159 PM AND WE WILL BE COLD ADVECTING SUN EVE.
RECORD WARM LOWS
SAT 12/13 SUN 12/14
GRI 37 - 1896 39 - 1896
HSI 36 - 1921 36 - 1928
WE HAVE HIGH CONFIDENCE SAT`S RECORDS WILL BE BROKEN AND MEDIUM
CONFIDENCE FOR SUN`S.
SAT: NO SUBSTANTIVE CHANGE FROM THU OR FRI. CLOUDY WITH AM FOG/MIST.
AM NOT CONVINCED ON DRZL POTENTIAL. MOISTURE DEPTH CASTS DOUBT SO
DRZL WAS DOWNGRADED TO JUST A "CHANCE".
SUN: LATE DAY COLD FRONTAL PASSAGE. ANOTHER CLOUDY START WITH AM
FOG/MIST. AN FGEN-DRIVEN COMMAHEAD BAND OF RAIN WILL DEVELOP OVER KS
AND LIFT NORTHWARD PRIMARILY IN THE AFTERNOON-EVENING HRS. BOTH THE
EC/GFS INDICATE SHOWALTER AND LIFTED INDICES TURNING SLIGHTLY
NEGATIVE. SO THUNDER IS NOW IN THE FCST FOR N-CNTRL KS TO COVER
THIS POSSIBILITY.
SUN NIGHT: IT`S A RACE TO SEE HOW FAST THE COLD AIR CAN WRAP INTO
THE COMMAHEAD AND CHANGE THE RAIN TO SNOW BEFORE PRECIP ENDS. LOTS
OF UNCERTAINTY REMAINS IN THIS TIME FRAME. SUGGEST EVERYONE
INTERESTED IN THIS POTENTIAL CONT TO MONITOR LATER FCSTS AND PREPARE
FOR PLOWABLE SNOW POSSIBILITY. HIGHEST PROBABLY IS CURRENTLY N AND W
OF THE TRI-CITIES.
FOR NOW MAINTAINED CONTINUITY WITH PREVIOUS FCST WITH RAIN MIXING
WITH AND CHANGING TO SNOW EXCEPT THE SE FRINGE OF THE FCST AREA...
ROUGHLY S OF A LINE FROM OSBORNE KS-YORK NE.
MON: BLUSTERY AND COLDER. POSSIBLY A LITTLE LEFTOVER LIGHT SNOW AS
THE LOW DEPARTS WRN IA INTO THE UPPER MIDWEST.
TUE: DRY BUT LOTS OF UNCERTAINTY ON TEMPS/CLOUD COVER. EC/GFS CROSS
SECTIONS SUGGEST A PERIOD OF SUBSTANTIAL MID-HIGH CLOUDINESS UNDER
A STRONG 110KT JET.
WED: DRY AND PROBABLY A LOT OF CLOUDS.
WED NIGHT-THU: WE CURRENTLY HAVE A LOW CHANCE OF RAIN/SNOW BUT IT
LOOKS DOUBTFUL BASED ON THE 00Z EC ENSEMBLE MEAN WHICH SUGGESTS THIS
NEXT DESERT SW SYSTEM REMAINS SUPPRESSED S OF THE FCST AREA.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 544 AM CST FRI DEC 12 2014
CEILING WILL BE TOUGH TO CALL THIS MORNING AS THEY TEETER ON THE
LOW END OF IFR. VISIBILITY IS ALSO ON THE EDGE OF CATEGORIES. AT
GRI...TEETERING BETWEEN VFR AND MVFR THIS MORNING...WHILE EAR WILL
BE ON THE CUSP MVFR/IFR. THERE COULD ALSO BE SOME VERY LIGHT
DRIZZLE THIS MORNING AS WELL. MORE VISIBILITY RESTRICTION IS
EXPECTED TONIGHT ALONG WITH SOME DRIZZLE. WE COULD GET SOME FOG
DURING THE OVERNIGHT...TOWARD THE END OF THE FORECAST.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR NEZ060-072-
082.
KS...NONE.
&&
$$
SHORT TERM...HEINLEIN
LONG TERM...HALBLAUB
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1105 PM MST SAT DEC 13 2014
.AVIATION...
06Z TAF CYCLE
A DEEPENING UPPER LEVEL TROUGH WILL CONTINUE TO FORM A CLOSED LOW
OVER CENTRAL NM TONIGHT...BEFORE GRADUALLY EJECTING NEWD ACROSS
THE TX/OK PANHANDLES ON SUNDAY. THE SYSTEM WILL CONTINUE TO PUSH A
WAVE OF PCPN WITH A PACIFIC COLD FRONT AND MVFR/IFR CONDITIONS IN
RAIN/SNOW AND MT OBSCURATIONS NEWD FROM THE CENTRAL MT CHAIN
ACROSS THE E PLAINS TONIGHT. WRAP AROUND SNOW SHOWERS AND MT
OBSCURATIONS SHOULD ALSO IMPACT WESTERN AND CENTRAL AREAS AT TIMES FOR
THE REMAINDER OF TONIGHT. IN ADDITION POCKETS OF MVFR/IFR
CONDITIONS SHOULD PERSIST INTO EARLY SUNDAY MORNING IN MANY
LOCATIONS W OF THE CENTRAL MT CHAIN DUE TO FOG AND LOW
CLOUDS...ESPECIALLY IN LOCATIONS THAT ACCUMULATED PCPN EARLIER IN
THE EVENING AND/OR OVERNIGHT. ON SUNDAY...WRAP AROUND SNOW AND RAIN SHOWERS
WILL FAVOR LOCATIONS N OF I-40 AND ALONG/E OF THE CONTDVD. SOME
OF THIS WRAP AROUND PCPN COULD BRIEFLY IMPACT KABQ...KSAF...KLVS
AND KTCC. ANOTHER SIGNIFICANT WEATHER CONCERN ON SUNDAY WILL BE
STRONG TO SEVERE NW WINDS IN THE WAKE OF THE EXITING UPPER LOW.
THE STRONGEST WINDS SHOULD BE FOUND E OF THE SANDIA AND MANZANO
MOUNTAINS TO THE TX BORDER WHERE OCCASIONAL GUSTS TO 50 KT ARE
EXPECTED. BLOWING SNOW COULD CREATE MVFR/IFR CONDITIONS IN THE
N MTS SUNDAY...EVEN DURING PERIODS OF NO PCPN.
44
&&
.PREV DISCUSSION...912 PM MST SAT DEC 13 2014...
.UPDATE...
LATEST MET MOS CAME IN WITH EVEN STRONGER WINDS FOR SUNDAY AS A
POWERFUL 60 KNOTS 700-50MB JET SLAMS EAST WITHIN THE BASE OF THE
DEEPENING UPPER LOW. MAIN AREA OF SNOW WILL BE OVER FOR AREAS ON
THE SOUTH SIDE FROM SANDIAS EAST TO CLINES CORNERS SO WILL END
WINTER HIGHLIGHT AT 12Z...THEN BEGIN HIGH WIND WARNING AFTER 14Z.
MAIN CONCERN WILL CERTAINLY BE THE WIND SUNDAY...WITH SOME BLSN
A POSSIBILITY. UPDATES AND NEW PRODUCT HIGHLIGHTS OUT SHORTLY.
GUYER
&&
.PREV DISCUSSION...547 PM MST SAT DEC 13 2014...
.UPDATE...
FOCUSED GREATEST POPS AND RAIN/SNOW CHANGEOVER WITH CURRENT TIMING
OF COLD FRONTAL BOUNDARY THROUGH TONIGHT. 12Z/18Z MODEL SUITE AND
LATEST SPC HRRR AND LOCAL 5KM WRF INDICATE A DYNAMIC EVENING ON
TAP FOR THE REGION. MAIN CHANGES WERE TO CONVERT SHOWER WORDING TO
STRATIFORM WORDING AND INCREASE INTENSITY FOR MTN AREAS. CURRENT
WINTER HIGHLIGHTS LOOK GOOD...ALTHOUGH CONCERNED TAOS AREA MAY GET
CLOSE TO WARNING IMPACTS. OTHERWISE...THE SANGRES LOOK TO BE IN
THE CROSS HAIRS THRU NOON SUNDAY WITH 8 TO 12 INCHES AND LOCALLY
UP TO 16...PARTICULARLY ON WEST AND NW FACING ASPECTS. OVERNIGHT
SHIFT WILL LIKELY ADD SOME WIND HIGHLIGHTS FOR TOMORROW AS STRONG
NW FLOW RACES OVER THE REGION BEHIND THE DEPARTING UPPER LOW.
GUYER
&&
.PREV DISCUSSION...233 PM MST SAT DEC 13 2014...
.SYNOPSIS...
A ROUND OF WEEKEND WINTER WEATHER FOR NEW MEXICO WILL CLEAR IN
TIME FOR THE WORK WEEK NEXT WEEK...WITH THE NEXT ROUND OF WINTER
WEATHER DUE IN BY MIDWEEK. A SERIES OF NORTH PACIFIC DISTURBANCES
WILL EXTEND THIS WINTER VISIT...WITH SKIES CLEARING ON FRIDAY.
ANOTHER SIZABLE WINTER STORM IS HEADED FOR NEW MEXICO LATE NEXT
WEEKEND.
&&
.DISCUSSION...
CURRENTLY...HIGH AMPLITUDE SHARP TROUGH EXTENDING FROM WESTERN
CANADA ACROSS ARIZONA TO NORTHERN MEXICO WITH ACCOMPANYING SURFACE
COLD FRONT ALONG THE WESTERN BORDER OF NEW MEXICO WILL BE THE
WEATHER PLAYER FOR THE REMAINDER OF THE WEEKEND...AS NEW MEXICO
BRACES FOR A ROUND OF RAIN AND SNOW.
MODELS...IN REASONABLE AGREEMENT ON BASIC STORY THROUGH THE
UPCOMING WORK WEEK AND INTO THE PRE HOLIDAY WEEKEND. TROUGH FROM
WESTERN CANADA TO NORTHERN MEXICO WILL SPREAD INTO WESTERN NEW
MEXICO THIS EVENING...DEEPEN AROUND A CLOSED LOW OVER NORTHERN NEW
MEXICO OVERNIGHT TONIGHT...AND SHEAR RAPIDLY INTO THE CENTRAL
PLAINS STATES THROUGH SUNDAY AFTERNOON. NORTHWEST FLOW ON
DOWNSTREAM LIMB OF HIGH AMPLITUDE RIDGE WILL PROVIDE A COUPLE OF
DAYS BREATHER IN ADVANCE OF LARGE SCALE PACIFIC TROUGH SYSTEM
DRIFTING INTO WESTERN NEW MEXICO BY WEDNESDAY. A QUICK WEDNESDAY
SHORTWAVE WILL BE FOLLOWED BY A MORE SUBSTANTIAL SYSTEM MOVING
INTO WESTERN NEW MEXICO ON THURSDAY...BUT MODELS ARE INTERESTING A
NEW WRINKLE ON PROJECTED SYSTEM PATH. BOTH HAVE SLOWED EASTWARD
PROGRESS OF THIS STRONGER SYSTEM...AND INSTEAD ARE NOW DIGGING IT
WELL SOUTH INTO CENTRAL CHIHUAHUA AS RIDGE BUILDS WITH AUTHORITY
FROM THE SOUTHERN CALIFORNIA COAST TO THE CANADIAN ROCKIES. THIS
RIDGE WILL MOVE ACROSS NEW MEXICO FOR AT LEAST THE FIRST HALF OF
NEXT WEEKEND...AS THE NEXT STORM SYSTEM OUT OF THE NORTHERN
PACIFIC RAMS INTO SOUTHERN CALIFORNIA AND MAKES VERY SLOW PROGRESS
INTO NORTHERN MEXICO NEAR THE NEW MEXICO BOOT HEEL BY MONDAY
MORNING...LEAVING THE BULK OF NEW MEXICO UNDER THE LESS ACTIVE
NORTHERN LIMBS OF THE TROUGH HEADING INTO THE HOLIDAY WEEK. THIS
IS A CHANGE...AND FUTURE RUNS WILL BE WATCHED CLOSELY TO VERIFY
THAT THE MECHANICS OF THIS PATTERN CAN BE MAINTAINED WITH SOME
DEGREE OF RUN TO RUN CONTINUITY.
OVERNIGHT...COOLER AIR MOVING IN FROM THE WEST...WITH TEMPERATURES
5 TO 10 DEGREES BELOW THOSE OBSERVED SATURDAY MORNING. WESTERN
SHOWERS WILL CHANGE OVER TO SNOW AND EXPAND COVERAGE RAPIDLY TO
THE EAST BY SUNDAY MORNING. HEAVIEST SNOW WILL FOCUS ON THE SAN
JUAN...TUSAS...AND JEMEZ MOUNTAINS EARLY IN THE OVERNIGHT...WITH
SNOW COVERAGE PICKING UP OVER THE SANGRE DE CRISTO RANGE BY SUNDAY
MORNING...WITH THESE SPOTS CONTINUING UNDER A WINTER WEATHER
WARNING. AWAY FROM THE HIGH COUNTRY...MUCH OF THE WEST AND CENTRAL
WILL PICK UP SOME OVERNIGHT SNOWFALL...WITH REDUCED SNOWFALL OVER
THE RIO GRANDE VALLEY. DEEPENING SURFACE LOW OVER NORTHEAST NEW
MEXICO AND EASTERN COLORADO WILL PROVIDE SUPPORTING FORCING FOR
INCREASING WIND SPEEDS OVERNIGHT...WITH BREEZY TO WINDY CONDITIONS
OVER THE EAST SLOPES AND ADJACENT PLAINS OF THE CENTRAL MOUNTAIN
CHAIN...AND OVER THE CONTINENTAL DIVIDE BY SUNRISE ON SUNDAY.
SOUTHERN PORTIONS OF THE SANGRE DE CRISTO RANGE AND ADJACENT
PLAINS ALONG INTERSTATE 40 COULD SEE SOME BLOWING SNOW WITH POOR
VISIBILITIES.
FOR SUNDAY...MUCH COOLER BUT TEMPERATURES WITHIN A FEW DEGREES OF
MID DECEMBER NORMALS. STORM COVERAGE WILL CONTINUE OVER THE
STATE...WITH SOMEWHAT REDUCED INTENSITY SOUTH OF INTERSTATE
40...AND STORM FOCUS SHIFTING TO THE SANGRE DE CRISTO
RANGE...RATON RIDGE...AND ON INTO SOUTHEAST COLORADO. GUSTY WINDS
WILL SHIFT NORTHWEST AS THE STORM SYSTEM DEPARTS...WITH STRONG
WINDS CONTINUING OVER THE CONTINENTAL DIVIDE...AND OUT OVER THE
CENTRAL MOUNTAIN CHAIN EAST SLOPES AND ADJACENT SLOPES THROUGH
SUNDAY AFTERNOON. WITH THE LAST OF THE SNOW OVER NORTHERN AND
WESTERN NEW MEXICO...NORTHEAST NEW MEXICO WILL BE IN FOR THE MIXED
BAG OF MOUNTAIN SNOW...AND THUNDERSTORMS OVER THE PLAINS GENERALLY
FROM INTERSTATE 40 NORTH AND INTERSTATE 25 EAST. SNOWFALL RATES
WILL DROP OFF THROUGH THE DAY...WITH GREATEST SNOWFALL
ACCUMULATION OVER THE SANGRE DE CRISTO RANGE AND OUT OVER RATON
RIDGE. HAVE ADDED RATON RIDGE AND JOHNSON MESA AREA TO SUITE OF
SNOW ADVISORIES FOR THE DAY ON SUNDAY TO COVER SNOW ISSUES ON
INTERSTATE 25 CROSSING THE COLORADO LINE.
FOR MONDAY...LAST OF THE SNOW WILL BE OUT OF NORTHEAST NEW MEXICO
BY MONDAY DAYBREAK...LEAVING CLEARING SKIES AND NORTHWEST FLOW
OVER THE STATE. WARMING IN THE WEST AND STEADY TEMPERATURES IN THE
EAST WILL KEEP THE STATE NEAR MID DECEMBER NORMALS FOR THE DAY.
WEAKENING SURFACE PRESSURE GRADIENT WILL ALSO DROP WIND
SPEEDS THROUGH THE DAY.
FOR TUESDAY...RIDGE SHEARING ACROSS NEW MEXICO TO LEAVE STATE IN
BROAD SOUTHWEST FLOW INTO TUESDAY AFTERNOON. NEXT INBOUND TROUGH
TAKING SHAPE ON THE WEST COAST WILL MOVE TO THE WESTERN NEW MEXICO
BORDER TUESDAY NIGHT...AND KICK OFF THE NEXT ROUND OF UNSETTLED
WEATHER THROUGH THE NEXT SEVERAL DAYS. SOME TUESDAY AFTERNOON
SOUTHWEST BREEZES OVER THE NORTHEAST CORNER OF THE STATE...BUT
WIND SPEEDS GENERALLY MODEST ELSEWHERE DURING THE DAY...AND SPEEDS
GENERALLY SUBDUED GOING INTO TUESDAY NIGHT.
OUTLOOK...WEDNESDAY THROUGH FRIDAY...FIRST SHORTWAVE BURST OUT OF
ARIZONA WILL PUSH ACROSS NEW MEXICO ON WEDNESDAY WITH MORE
SUBSTANTIAL SYSTEM ARRIVING OVER THE STATE ON THURSDAY. SYSTEM
WILL CLEAR OFF TO THE EAST ON FRIDAY WITH SHOWER COVERAGE TAPERING
OFF. WITH MORE SOUTHERLY EXCURSION...SNOW COVERAGE THURSDAY MAY
SHOW SOME PREFERENCE FOR AREAS SOUTH OF INTERSTATE 40...WITH
REDUCED AMOUNTS OVER THE HIGH COUNTRY TO THE NORTH...AND THIS
TREND WILL BE WATCHED CAREFULLY IN THE DAYS TO COME.
OTHERWISE...VERY MODEST COOLING TREND WILL PUSH MOST SPOTS 3 TO 8
DEGREES BELOW MID DECEMBER NORMALS BY FRIDAY. WITH A LACK OF
STRONG SURFACE PRESSURE GRADIENTS...WIND SPEEDS WILL BE RUNNING ON
THE MODEST SIDE ALL THREE DAYS.
SHY
&&
.FIRE WEATHER...
A VERY ACTIVE WEATHER PATTERN WILL COMMENCE TODAY AND CONTINUE
THROUGH THE NEXT SEVEN DAYS. A VIGOROUS STORM SYSTEM AND STRONG
FRONTAL BAND OF PRECIPITATION WILL STRENGTHEN OVER WRN NM LATE THIS
AFTERNOON AND CONTINUE THROUGH SUNDAY MORNING. WETTING PRECIPITATION
IS EXPECTED OVER MUCH OF THE WESTERN HALF OF NEW MEXICO WITH
SIGNIFICANT SNOWFALL OVER THE NORTHERN MOUNTAINS AND PERHAPS THE
SANDIAS AND MANZANOS. PRECIPITATION WILL INCREASE IN COVERAGE AND
INTENSITY LATE THIS AFTERNOON INTO THIS EVENING OVER WESTERN
AREAS...SPREADING INTO CENTRAL NEW MEXICO AROUND MID-EVENING. SNOW
LEVELS WILL DROP RAPIDLY BEHIND THE ASSOCIATED SURFACE COLD FRONT.
DEEPENING SURFACE LOW OVER FAR NE NM WILL COMBINE WITH STRONG NW
WINDS NEAR MOUNTAIN TOP LEVEL TO CREATE WINDY CONDITIONS SUNDAY.
MAIN AREAS AFFECTED BY THE STRONGEST WINDS (LOCALLY AS HIGH AS 55
MPH) WILL BE THE SANDIA AND MANZANO MOUNTAINS EAST TO THE CENTRAL
HIGHLANDS FROM SUNDAY MORNING THROUGH SUNDAY EVENING. AREAS OF SNOW
AND BLOWING SNOW WILL DEVELOP SUNDAY MORNING IN THESE SAME AREAS.
TEMPERATURES SUNDAY WILL BE MUCH COLDER...WITH HIGHS BELOW AVERAGE
FOR THE FIRST TIME THIS MONTH.
A TRANQUIL WEATHER PATTERN UNDER A HIGH PRESSURE RIDGE/SW FLOW ALOFT
WILL MOVE IN FOR MONDAY AND TUESDAY. VENTILATION RATES WILL DROP TO
POOR ALL AREAS MONDAY AS THE LOW LEVEL COLD AIR WILL BE SLOW TO
MODIFY AND WARMER AIR ALOFT MOVES OVERHEAD. VENT RATES IMPROVE
TUESDAY AS SOUTHWEST WINDS INCREASE SOMEWHAT.
THE NEXT PACIFIC TROUGH APPROACHES FROM THE WEST TUESDAY NIGHT. GFS
AND ECMWF IN GOOD AGREEMENT THROUGH WEDNESDAY...BRINGING SCATTERED
SNOW SHOWERS TO MUCH OF WESTERN AND NWRN NM DURING THE DAY WEDNESDAY
INTO WEDNESDAY NIGHT. VENTILATION RATES CONTINUE TO IMPROVE
WEDNESDAY AS COLDER AIR ALOFT ASSOCIATED WITH THE TROUGH MOVES OVER.
MODELS BEGIN TO DIVERGE LATE IN THE WEEK WITH REGARD TO HOW FAR
SOUTH A TRAILING SYSTEM WILL TRACK FOR THE LATTER HALF OF THE WORK
WEEK.
33
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ502>506-521>523.
HIGH WIND WARNING FROM 7 AM TO 8 PM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ521>523-533>537.
WINTER WEATHER ADVISORY UNTIL 5 PM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ516>518.
WINTER STORM WARNING UNTIL 5 PM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ510>515.
WINTER WEATHER ADVISORY FROM 5 AM TO 5 PM MST SUNDAY FOR THE
FOLLOWING ZONES...NMZ527.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
912 PM MST SAT DEC 13 2014
.UPDATE...
LATEST MET MOS CAME IN WITH EVEN STRONGER WINDS FOR SUNDAY AS A
POWERFUL 60 KNOTS 700-50MB JET SLAMS EAST WITHIN THE BASE OF THE
DEEPENING UPPER LOW. MAIN AREA OF SNOW WILL BE OVER FOR AREAS ON
THE SOUTH SIDE FROM SANDIAS EAST TO CLINES CORNERS SO WILL END
WINTER HIGHLIGHT AT 12Z...THEN BEGIN HIGH WIND WARNING AFTER 14Z.
MAIN CONCERN WILL CERTAINLY BE THE WIND SUNDAY...WITH SOME BLSN
A POSSIBILITY. UPDATES AND NEW PRODUCT HIGHLIGHTS OUT SHORTLY.
GUYER
&&
.PREV DISCUSSION...547 PM MST SAT DEC 13 2014...
.UPDATE...
FOCUSED GREATEST POPS AND RAIN/SNOW CHANGEOVER WITH CURRENT TIMING
OF COLD FRONTAL BOUNDARY THROUGH TONIGHT. 12Z/18Z MODEL SUITE AND
LATEST SPC HRRR AND LOCAL 5KM WRF INDICATE A DYNAMIC EVENING ON
TAP FOR THE REGION. MAIN CHANGES WERE TO CONVERT SHOWER WORDING TO
STRATIFORM WORDING AND INCREASE INTENSITY FOR MTN AREAS. CURRENT
WINTER HIGHLIGHTS LOOK GOOD...ALTHOUGH CONCERNED TAOS AREA MAY GET
CLOSE TO WARNING IMPACTS. OTHERWISE...THE SANGRES LOOK TO BE IN
THE CROSS HAIRS THRU NOON SUNDAY WITH 8 TO 12 INCHES AND LOCALLY
UP TO 16...PARTICULARLY ON WEST AND NW FACING ASPECTS. OVERNIGHT
SHIFT WILL LIKELY ADD SOME WIND HIGHLIGHTS FOR TOMORROW AS STRONG
NW FLOW RACES OVER THE REGION BEHIND THE DEPARTING UPPER LOW.
GUYER
&&
.PREV DISCUSSION...508 PM MST SAT DEC 13 2014...
.AVIATION...
00Z TAF CYCLE
A DEEPENING UPPER LEVEL TROUGH WILL FORM A CLOSED LOW OVER CENTRAL
NM TONIGHT...BEFORE GRADUALLY EJECTING NEWD ACROSS THE TX/OK
PANHANDLES ON SUNDAY. THE SYSTEM WILL CONTINUE TO PUSH A WAVE OF
PCPN WITH A PACIFIC COLD FRONT AND MVFR/IFR CONDITIONS IN
RAIN/SNOW AND MT OBSCURATIONS EASTWARD ACROSS THE FORECAST AREA
TONIGHT. MESOSCALE MODELS DEPICT THE PCPN TAPERING OFF AT KGUP AND
KFMN AFT 04 OR 05Z...THEN AT KAEG/KABQ AROUND 09Z. HOWEVER...FLIGHT
CATEGORY RESTRICTIONS SHOULD PERSIST INTO EARLY SUNDAY MORNING DUE
TO FOG AND LOW CLOUDS. ON SUNDAY...WRAP AROUND MOISTURE WILL FAVOR
LOCATIONS N OF I-40 AND ALONG/E OF THE CONTDVD FOR PERSISTENT
LINGERING RAIN/SNOW. SOME OF THIS WRAP AROUND PCPN COULD IMPACT
KSAF...KLVS AND KTCC SUNDAY AFTN.
44
&&
.PREV DISCUSSION...233 PM MST SAT DEC 13 2014...
.SYNOPSIS...
A ROUND OF WEEKEND WINTER WEATHER FOR NEW MEXICO WILL CLEAR IN
TIME FOR THE WORK WEEK NEXT WEEK...WITH THE NEXT ROUND OF WINTER
WEATHER DUE IN BY MIDWEEK. A SERIES OF NORTH PACIFIC DISTURBANCES
WILL EXTEND THIS WINTER VISIT...WITH SKIES CLEARING ON FRIDAY.
ANOTHER SIZABLE WINTER STORM IS HEADED FOR NEW MEXICO LATE NEXT
WEEKEND.
&&
.DISCUSSION...
CURRENTLY...HIGH AMPLITUDE SHARP TROUGH EXTENDING FROM WESTERN
CANADA ACROSS ARIZONA TO NORTHERN MEXICO WITH ACCOMPANYING SURFACE
COLD FRONT ALONG THE WESTERN BORDER OF NEW MEXICO WILL BE THE
WEATHER PLAYER FOR THE REMAINDER OF THE WEEKEND...AS NEW MEXICO
BRACES FOR A ROUND OF RAIN AND SNOW.
MODELS...IN REASONABLE AGREEMENT ON BASIC STORY THROUGH THE
UPCOMING WORK WEEK AND INTO THE PRE HOLIDAY WEEKEND. TROUGH FROM
WESTERN CANADA TO NORTHERN MEXICO WILL SPREAD INTO WESTERN NEW
MEXICO THIS EVENING...DEEPEN AROUND A CLOSED LOW OVER NORTHERN NEW
MEXICO OVERNIGHT TONIGHT...AND SHEAR RAPIDLY INTO THE CENTRAL
PLAINS STATES THROUGH SUNDAY AFTERNOON. NORTHWEST FLOW ON
DOWNSTREAM LIMB OF HIGH AMPLITUDE RIDGE WILL PROVIDE A COUPLE OF
DAYS BREATHER IN ADVANCE OF LARGE SCALE PACIFIC TROUGH SYSTEM
DRIFTING INTO WESTERN NEW MEXICO BY WEDNESDAY. A QUICK WEDNESDAY
SHORTWAVE WILL BE FOLLOWED BY A MORE SUBSTANTIAL SYSTEM MOVING
INTO WESTERN NEW MEXICO ON THURSDAY...BUT MODELS ARE INTERESTING A
NEW WRINKLE ON PROJECTED SYSTEM PATH. BOTH HAVE SLOWED EASTWARD
PROGRESS OF THIS STRONGER SYSTEM...AND INSTEAD ARE NOW DIGGING IT
WELL SOUTH INTO CENTRAL CHIHUAHUA AS RIDGE BUILDS WITH AUTHORITY
FROM THE SOUTHERN CALIFORNIA COAST TO THE CANADIAN ROCKIES. THIS
RIDGE WILL MOVE ACROSS NEW MEXICO FOR AT LEAST THE FIRST HALF OF
NEXT WEEKEND...AS THE NEXT STORM SYSTEM OUT OF THE NORTHERN
PACIFIC RAMS INTO SOUTHERN CALIFORNIA AND MAKES VERY SLOW PROGRESS
INTO NORTHERN MEXICO NEAR THE NEW MEXICO BOOT HEEL BY MONDAY
MORNING...LEAVING THE BULK OF NEW MEXICO UNDER THE LESS ACTIVE
NORTHERN LIMBS OF THE TROUGH HEADING INTO THE HOLIDAY WEEK. THIS
IS A CHANGE...AND FUTURE RUNS WILL BE WATCHED CLOSELY TO VERIFY
THAT THE MECHANICS OF THIS PATTERN CAN BE MAINTAINED WITH SOME
DEGREE OF RUN TO RUN CONTINUITY.
OVERNIGHT...COOLER AIR MOVING IN FROM THE WEST...WITH TEMPERATURES
5 TO 10 DEGREES BELOW THOSE OBSERVED SATURDAY MORNING. WESTERN
SHOWERS WILL CHANGE OVER TO SNOW AND EXPAND COVERAGE RAPIDLY TO
THE EAST BY SUNDAY MORNING. HEAVIEST SNOW WILL FOCUS ON THE SAN
JUAN...TUSAS...AND JEMEZ MOUNTAINS EARLY IN THE OVERNIGHT...WITH
SNOW COVERAGE PICKING UP OVER THE SANGRE DE CRISTO RANGE BY SUNDAY
MORNING...WITH THESE SPOTS CONTINUING UNDER A WINTER WEATHER
WARNING. AWAY FROM THE HIGH COUNTRY...MUCH OF THE WEST AND CENTRAL
WILL PICK UP SOME OVERNIGHT SNOWFALL...WITH REDUCED SNOWFALL OVER
THE RIO GRANDE VALLEY. DEEPENING SURFACE LOW OVER NORTHEAST NEW
MEXICO AND EASTERN COLORADO WILL PROVIDE SUPPORTING FORCING FOR
INCREASING WIND SPEEDS OVERNIGHT...WITH BREEZY TO WINDY CONDITIONS
OVER THE EAST SLOPES AND ADJACENT PLAINS OF THE CENTRAL MOUNTAIN
CHAIN...AND OVER THE CONTINENTAL DIVIDE BY SUNRISE ON SUNDAY.
SOUTHERN PORTIONS OF THE SANGRE DE CRISTO RANGE AND ADJACENT
PLAINS ALONG INTERSTATE 40 COULD SEE SOME BLOWING SNOW WITH POOR
VISIBILITIES.
FOR SUNDAY...MUCH COOLER BUT TEMPERATURES WITHIN A FEW DEGREES OF
MID DECEMBER NORMALS. STORM COVERAGE WILL CONTINUE OVER THE
STATE...WITH SOMEWHAT REDUCED INTENSITY SOUTH OF INTERSTATE
40...AND STORM FOCUS SHIFTING TO THE SANGRE DE CRISTO
RANGE...RATON RIDGE...AND ON INTO SOUTHEAST COLORADO. GUSTY WINDS
WILL SHIFT NORTHWEST AS THE STORM SYSTEM DEPARTS...WITH STRONG
WINDS CONTINUING OVER THE CONTINENTAL DIVIDE...AND OUT OVER THE
CENTRAL MOUNTAIN CHAIN EAST SLOPES AND ADJACENT SLOPES THROUGH
SUNDAY AFTERNOON. WITH THE LAST OF THE SNOW OVER NORTHERN AND
WESTERN NEW MEXICO...NORTHEAST NEW MEXICO WILL BE IN FOR THE MIXED
BAG OF MOUNTAIN SNOW...AND THUNDERSTORMS OVER THE PLAINS GENERALLY
FROM INTERSTATE 40 NORTH AND INTERSTATE 25 EAST. SNOWFALL RATES
WILL DROP OFF THROUGH THE DAY...WITH GREATEST SNOWFALL
ACCUMULATION OVER THE SANGRE DE CRISTO RANGE AND OUT OVER RATON
RIDGE. HAVE ADDED RATON RIDGE AND JOHNSON MESA AREA TO SUITE OF
SNOW ADVISORIES FOR THE DAY ON SUNDAY TO COVER SNOW ISSUES ON
INTERSTATE 25 CROSSING THE COLORADO LINE.
FOR MONDAY...LAST OF THE SNOW WILL BE OUT OF NORTHEAST NEW MEXICO
BY MONDAY DAYBREAK...LEAVING CLEARING SKIES AND NORTHWEST FLOW
OVER THE STATE. WARMING IN THE WEST AND STEADY TEMPERATURES IN THE
EAST WILL KEEP THE STATE NEAR MID DECEMBER NORMALS FOR THE DAY.
WEAKENING SURFACE PRESSURE GRADIENT WILL ALSO DROP WIND
SPEEDS THROUGH THE DAY.
FOR TUESDAY...RIDGE SHEARING ACROSS NEW MEXICO TO LEAVE STATE IN
BROAD SOUTHWEST FLOW INTO TUESDAY AFTERNOON. NEXT INBOUND TROUGH
TAKING SHAPE ON THE WEST COAST WILL MOVE TO THE WESTERN NEW MEXICO
BORDER TUESDAY NIGHT...AND KICK OFF THE NEXT ROUND OF UNSETTLED
WEATHER THROUGH THE NEXT SEVERAL DAYS. SOME TUESDAY AFTERNOON
SOUTHWEST BREEZES OVER THE NORTHEAST CORNER OF THE STATE...BUT
WIND SPEEDS GENERALLY MODEST ELSEWHERE DURING THE DAY...AND SPEEDS
GENERALLY SUBDUED GOING INTO TUESDAY NIGHT.
OUTLOOK...WEDNESDAY THROUGH FRIDAY...FIRST SHORTWAVE BURST OUT OF
ARIZONA WILL PUSH ACROSS NEW MEXICO ON WEDNESDAY WITH MORE
SUBSTANTIAL SYSTEM ARRIVING OVER THE STATE ON THURSDAY. SYSTEM
WILL CLEAR OFF TO THE EAST ON FRIDAY WITH SHOWER COVERAGE TAPERING
OFF. WITH MORE SOUTHERLY EXCURSION...SNOW COVERAGE THURSDAY MAY
SHOW SOME PREFERENCE FOR AREAS SOUTH OF INTERSTATE 40...WITH
REDUCED AMOUNTS OVER THE HIGH COUNTRY TO THE NORTH...AND THIS
TREND WILL BE WATCHED CAREFULLY IN THE DAYS TO COME.
OTHERWISE...VERY MODEST COOLING TREND WILL PUSH MOST SPOTS 3 TO 8
DEGREES BELOW MID DECEMBER NORMALS BY FRIDAY. WITH A LACK OF
STRONG SURFACE PRESSURE GRADIENTS...WIND SPEEDS WILL BE RUNNING ON
THE MODEST SIDE ALL THREE DAYS.
SHY
&&
.FIRE WEATHER...
A VERY ACTIVE WEATHER PATTERN WILL COMMENCE TODAY AND CONTINUE
THROUGH THE NEXT SEVEN DAYS. A VIGOROUS STORM SYSTEM AND STRONG
FRONTAL BAND OF PRECIPITATION WILL STRENGTHEN OVER WRN NM LATE THIS
AFTERNOON AND CONTINUE THROUGH SUNDAY MORNING. WETTING PRECIPITATION
IS EXPECTED OVER MUCH OF THE WESTERN HALF OF NEW MEXICO WITH
SIGNIFICANT SNOWFALL OVER THE NORTHERN MOUNTAINS AND PERHAPS THE
SANDIAS AND MANZANOS. PRECIPITATION WILL INCREASE IN COVERAGE AND
INTENSITY LATE THIS AFTERNOON INTO THIS EVENING OVER WESTERN
AREAS...SPREADING INTO CENTRAL NEW MEXICO AROUND MID-EVENING. SNOW
LEVELS WILL DROP RAPIDLY BEHIND THE ASSOCIATED SURFACE COLD FRONT.
DEEPENING SURFACE LOW OVER FAR NE NM WILL COMBINE WITH STRONG NW
WINDS NEAR MOUNTAIN TOP LEVEL TO CREATE WINDY CONDITIONS SUNDAY.
MAIN AREAS AFFECTED BY THE STRONGEST WINDS (LOCALLY AS HIGH AS 55
MPH) WILL BE THE SANDIA AND MANZANO MOUNTAINS EAST TO THE CENTRAL
HIGHLANDS FROM SUNDAY MORNING THROUGH SUNDAY EVENING. AREAS OF SNOW
AND BLOWING SNOW WILL DEVELOP SUNDAY MORNING IN THESE SAME AREAS.
TEMPERATURES SUNDAY WILL BE MUCH COLDER...WITH HIGHS BELOW AVERAGE
FOR THE FIRST TIME THIS MONTH.
A TRANQUIL WEATHER PATTERN UNDER A HIGH PRESSURE RIDGE/SW FLOW ALOFT
WILL MOVE IN FOR MONDAY AND TUESDAY. VENTILATION RATES WILL DROP TO
POOR ALL AREAS MONDAY AS THE LOW LEVEL COLD AIR WILL BE SLOW TO
MODIFY AND WARMER AIR ALOFT MOVES OVERHEAD. VENT RATES IMPROVE
TUESDAY AS SOUTHWEST WINDS INCREASE SOMEWHAT.
THE NEXT PACIFIC TROUGH APPROACHES FROM THE WEST TUESDAY NIGHT. GFS
AND ECMWF IN GOOD AGREEMENT THROUGH WEDNESDAY...BRINGING SCATTERED
SNOW SHOWERS TO MUCH OF WESTERN AND NWRN NM DURING THE DAY WEDNESDAY
INTO WEDNESDAY NIGHT. VENTILATION RATES CONTINUE TO IMPROVE
WEDNESDAY AS COLDER AIR ALOFT ASSOCIATED WITH THE TROUGH MOVES OVER.
MODELS BEGIN TO DIVERGE LATE IN THE WEEK WITH REGARD TO HOW FAR
SOUTH A TRAILING SYSTEM WILL TRACK FOR THE LATTER HALF OF THE WORK
WEEK.
33
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ502>506-521>523.
HIGH WIND WARNING FROM 7 AM TO 8 PM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ521>523-533>537.
WINTER WEATHER ADVISORY UNTIL 5 PM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ516>518.
WINTER STORM WARNING UNTIL 5 PM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ510>515.
WINTER WEATHER ADVISORY FROM 5 AM TO 5 PM MST SUNDAY FOR THE
FOLLOWING ZONES...NMZ527.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
547 PM MST SAT DEC 13 2014
.UPDATE...
FOCUSED GREATEST POPS AND RAIN/SNOW CHANGEOVER WITH CURRENT TIMING
OF COLD FRONTAL BOUNDARY THROUGH TONIGHT. 12Z/18Z MODEL SUITE AND
LATEST SPC HRRR AND LOCAL 5KM WRF INDICATE A DYNAMIC EVENING ON
TAP FOR THE REGION. MAIN CHANGES WERE TO CONVERT SHOWER WORDING TO
STRATIFORM WORDING AND INCREASE INTENSITY FOR MTN AREAS. CURRENT
WINTER HIGHLIGHTS LOOK GOOD...ALTHOUGH CONCERNED TAOS AREA MAY GET
CLOSE TO WARNING IMPACTS. OTHERWISE...THE SANGRES LOOK TO BE IN
THE CROSS HAIRS THRU NOON SUNDAY WITH 8 TO 12 INCHES AND LOCALLY
UP TO 16...PARTICULARY ON WEST AND NW FACING ASPECTS. OVERNIGHT
SHIFT WILL LIKELY ADD SOME WIND HIGHLIGHTS FOR TOMORROW AS STRONG
NW FLOW RACES OVER THE REGION BEHIND THE DEPARTING UPPER LOW.
GUYER
&&
.PREV DISCUSSION...508 PM MST SAT DEC 13 2014...
.AVIATION...
00Z TAF CYCLE
A DEEPENING UPPER LEVEL TROUGH WILL FORM A CLOSED LOW OVER CENTRAL
NM TONIGHT...BEFORE GRADUALLY EJECTING NEWD ACROSS THE TX/OK
PANHANDLES ON SUNDAY. THE SYSTEM WILL CONTINUE TO PUSH A WAVE OF
PCPN WITH A PACIFIC COLD FRONT AND MVFR/IFR CONDITIONS IN
RAIN/SNOW AND MT OBSCURATIONS EASTWARD ACROSS THE FORECAST AREA
TONIGHT. MESOSCALE MODELS DEPICT THE PCPN TAPERING OFF AT KGUP AND
KFMN AFT 04 OR 05Z...THEN AT KAEG/KABQ AROUND 09Z. HOWEVER...FLIGHT
CATEGORY RESTRICTIONS SHOULD PERSIST INTO EARLY SUNDAY MORNING DUE
TO FOG AND LOW CLOUDS. ON SUNDAY...WRAP AROUND MOISTURE WILL FAVOR
LOCATIONS N OF I-40 AND ALONG/E OF THE CONTDVD FOR PERSISTENT
LINGERING RAIN/SNOW. SOME OF THIS WRAP AROUND PCPN COULD IMPACT
KSAF...KLVS AND KTCC SUNDAY AFTN.
44
&&
.PREV DISCUSSION...233 PM MST SAT DEC 13 2014...
.SYNOPSIS...
A ROUND OF WEEKEND WINTER WEATHER FOR NEW MEXICO WILL CLEAR IN
TIME FOR THE WORK WEEK NEXT WEEK...WITH THE NEXT ROUND OF WINTER
WEATHER DUE IN BY MIDWEEK. A SERIES OF NORTH PACIFIC DISTURBANCES
WILL EXTEND THIS WINTER VISIT...WITH SKIES CLEARING ON FRIDAY.
ANOTHER SIZABLE WINTER STORM IS HEADED FOR NEW MEXICO LATE NEXT
WEEKEND.
&&
.DISCUSSION...
CURRENTLY...HIGH AMPLITUDE SHARP TROUGH EXTENDING FROM WESTERN
CANADA ACROSS ARIZONA TO NORTHERN MEXICO WITH ACCOMPANYING SURFACE
COLD FRONT ALONG THE WESTERN BORDER OF NEW MEXICO WILL BE THE
WEATHER PLAYER FOR THE REMAINDER OF THE WEEKEND...AS NEW MEXICO
BRACES FOR A ROUND OF RAIN AND SNOW.
MODELS...IN REASONABLE AGREEMENT ON BASIC STORY THROUGH THE
UPCOMING WORK WEEK AND INTO THE PRE HOLIDAY WEEKEND. TROUGH FROM
WESTERN CANADA TO NORTHERN MEXICO WILL SPREAD INTO WESTERN NEW
MEXICO THIS EVENING...DEEPEN AROUND A CLOSED LOW OVER NORTHERN NEW
MEXICO OVERNIGHT TONIGHT...AND SHEAR RAPIDLY INTO THE CENTRAL
PLAINS STATES THROUGH SUNDAY AFTERNOON. NORTHWEST FLOW ON
DOWNSTREAM LIMB OF HIGH AMPLITUDE RIDGE WILL PROVIDE A COUPLE OF
DAYS BREATHER IN ADVANCE OF LARGE SCALE PACIFIC TROUGH SYSTEM
DRIFTING INTO WESTERN NEW MEXICO BY WEDNESDAY. A QUICK WEDNESDAY
SHORTWAVE WILL BE FOLLOWED BY A MORE SUBSTANTIAL SYSTEM MOVING
INTO WESTERN NEW MEXICO ON THURSDAY...BUT MODELS ARE INTERESTING A
NEW WRINKLE ON PROJECTED SYSTEM PATH. BOTH HAVE SLOWED EASTWARD
PROGRESS OF THIS STRONGER SYSTEM...AND INSTEAD ARE NOW DIGGING IT
WELL SOUTH INTO CENTRAL CHIHUAHUA AS RIDGE BUILDS WITH AUTHORITY
FROM THE SOUTHERN CALIFORNIA COAST TO THE CANADIAN ROCKIES. THIS
RIDGE WILL MOVE ACROSS NEW MEXICO FOR AT LEAST THE FIRST HALF OF
NEXT WEEKEND...AS THE NEXT STORM SYSTEM OUT OF THE NORTHERN
PACIFIC RAMS INTO SOUTHERN CALIFORNIA AND MAKES VERY SLOW PROGRESS
INTO NORTHERN MEXICO NEAR THE NEW MEXICO BOOT HEEL BY MONDAY
MORNING...LEAVING THE BULK OF NEW MEXICO UNDER THE LESS ACTIVE
NORTHERN LIMBS OF THE TROUGH HEADING INTO THE HOLIDAY WEEK. THIS
IS A CHANGE...AND FUTURE RUNS WILL BE WATCHED CLOSELY TO VERIFY
THAT THE MECHANICS OF THIS PATTERN CAN BE MAINTAINED WITH SOME
DEGREE OF RUN TO RUN CONTINUITY.
OVERNIGHT...COOLER AIR MOVING IN FROM THE WEST...WITH TEMPERATURES
5 TO 10 DEGREES BELOW THOSE OBSERVED SATURDAY MORNING. WESTERN
SHOWERS WILL CHANGE OVER TO SNOW AND EXPAND COVERAGE RAPIDLY TO
THE EAST BY SUNDAY MORNING. HEAVIEST SNOW WILL FOCUS ON THE SAN
JUAN...TUSAS...AND JEMEZ MOUNTAINS EARLY IN THE OVERNIGHT...WITH
SNOW COVERAGE PICKING UP OVER THE SANGRE DE CRISTO RANGE BY SUNDAY
MORNING...WITH THESE SPOTS CONTINUING UNDER A WINTER WEATHER
WARNING. AWAY FROM THE HIGH COUNTRY...MUCH OF THE WEST AND CENTRAL
WILL PICK UP SOME OVERNIGHT SNOWFALL...WITH REDUCED SNOWFALL OVER
THE RIO GRANDE VALLEY. DEEPENING SURFACE LOW OVER NORTHEAST NEW
MEXICO AND EASTERN COLORADO WILL PROVIDE SUPPORTING FORCING FOR
INCREASING WIND SPEEDS OVERNIGHT...WITH BREEZY TO WINDY CONDITIONS
OVER THE EAST SLOPES AND ADJACENT PLAINS OF THE CENTRAL MOUNTAIN
CHAIN...AND OVER THE CONTINENTAL DIVIDE BY SUNRISE ON SUNDAY.
SOUTHERN PORTIONS OF THE SANGRE DE CRISTO RANGE AND ADJACENT
PLAINS ALONG INTERSTATE 40 COULD SEE SOME BLOWING SNOW WITH POOR
VISIBILITIES.
FOR SUNDAY...MUCH COOLER BUT TEMPERATURES WITHIN A FEW DEGREES OF
MID DECEMBER NORMALS. STORM COVERAGE WILL CONTINUE OVER THE
STATE...WITH SOMEWHAT REDUCED INTENSITY SOUTH OF INTERSTATE
40...AND STORM FOCUS SHIFTING TO THE SANGRE DE CRISTO
RANGE...RATON RIDGE...AND ON INTO SOUTHEAST COLORADO. GUSTY WINDS
WILL SHIFT NORTHWEST AS THE STORM SYSTEM DEPARTS...WITH STRONG
WINDS CONTINUING OVER THE CONTINENTAL DIVIDE...AND OUT OVER THE
CENTRAL MOUNTAIN CHAIN EAST SLOPES AND ADJACENT SLOPES THROUGH
SUNDAY AFTERNOON. WITH THE LAST OF THE SNOW OVER NORTHERN AND
WESTERN NEW MEXICO...NORTHEAST NEW MEXICO WILL BE IN FOR THE MIXED
BAG OF MOUNTAIN SNOW...AND THUNDERSTORMS OVER THE PLAINS GENERALLY
FROM INTERSTATE 40 NORTH AND INTERSTATE 25 EAST. SNOWFALL RATES
WILL DROP OFF THROUGH THE DAY...WITH GREATEST SNOWFALL
ACCUMULATION OVER THE SANGRE DE CRISTO RANGE AND OUT OVER RATON
RIDGE. HAVE ADDED RATON RIDGE AND JOHNSON MESA AREA TO SUITE OF
SNOW ADVISORIES FOR THE DAY ON SUNDAY TO COVER SNOW ISSUES ON
INTERSTATE 25 CROSSING THE COLORADO LINE.
FOR MONDAY...LAST OF THE SNOW WILL BE OUT OF NORTHEAST NEW MEXICO
BY MONDAY DAYBREAK...LEAVING CLEARING SKIES AND NORTHWEST FLOW
OVER THE STATE. WARMING IN THE WEST AND STEADY TEMPERATURES IN THE
EAST WILL KEEP THE STATE NEAR MID DECEMBER NORMALS FOR THE DAY.
WEAKENING SURFACE PRESSURE GRADIENT WILL ALSO DROP WIND
SPEEDS THROUGH THE DAY.
FOR TUESDAY...RIDGE SHEARING ACROSS NEW MEXICO TO LEAVE STATE IN
BROAD SOUTHWEST FLOW INTO TUESDAY AFTERNOON. NEXT INBOUND TROUGH
TAKING SHAPE ON THE WEST COAST WILL MOVE TO THE WESTERN NEW MEXICO
BORDER TUESDAY NIGHT...AND KICK OFF THE NEXT ROUND OF UNSETTLED
WEATHER THROUGH THE NEXT SEVERAL DAYS. SOME TUESDAY AFTERNOON
SOUTHWEST BREEZES OVER THE NORTHEAST CORNER OF THE STATE...BUT
WIND SPEEDS GENERALLY MODEST ELSEWHERE DURING THE DAY...AND SPEEDS
GENERALLY SUBDUED GOING INTO TUESDAY NIGHT.
OUTLOOK...WEDNESDAY THROUGH FRIDAY...FIRST SHORTWAVE BURST OUT OF
ARIZONA WILL PUSH ACROSS NEW MEXICO ON WEDNESDAY WITH MORE
SUBSTANTIAL SYSTEM ARRIVING OVER THE STATE ON THURSDAY. SYSTEM
WILL CLEAR OFF TO THE EAST ON FRIDAY WITH SHOWER COVERAGE TAPERING
OFF. WITH MORE SOUTHERLY EXCURSION...SNOW COVERAGE THURSDAY MAY
SHOW SOME PREFERENCE FOR AREAS SOUTH OF INTERSTATE 40...WITH
REDUCED AMOUNTS OVER THE HIGH COUNTRY TO THE NORTH...AND THIS
TREND WILL BE WATCHED CAREFULLY IN THE DAYS TO COME.
OTHERWISE...VERY MODEST COOLING TREND WILL PUSH MOST SPOTS 3 TO 8
DEGREES BELOW MID DECEMBER NORMALS BY FRIDAY. WITH A LACK OF
STRONG SURFACE PRESSURE GRADIENTS...WIND SPEEDS WILL BE RUNNING ON
THE MODEST SIDE ALL THREE DAYS.
SHY
&&
.FIRE WEATHER...
A VERY ACTIVE WEATHER PATTERN WILL COMMENCE TODAY AND CONTINUE
THROUGH THE NEXT SEVEN DAYS. A VIGOROUS STORM SYSTEM AND STRONG
FRONTAL BAND OF PRECIPITATION WILL STRENGTHEN OVER WRN NM LATE THIS
AFTERNOON AND CONTINUE THROUGH SUNDAY MORNING. WETTING PRECIPITATION
IS EXPECTED OVER MUCH OF THE WESTERN HALF OF NEW MEXICO WITH
SIGNIFICANT SNOWFALL OVER THE NORTHERN MOUNTAINS AND PERHAPS THE
SANDIAS AND MANZANOS. PRECIPITATION WILL INCREASE IN COVERAGE AND
INTENSITY LATE THIS AFTERNOON INTO THIS EVENING OVER WESTERN
AREAS...SPREADING INTO CENTRAL NEW MEXICO AROUND MID-EVENING. SNOW
LEVELS WILL DROP RAPIDLY BEHIND THE ASSOCIATED SURFACE COLD FRONT.
DEEPENING SURFACE LOW OVER FAR NE NM WILL COMBINE WITH STRONG NW
WINDS NEAR MOUNTAIN TOP LEVEL TO CREATE WINDY CONDITIONS SUNDAY.
MAIN AREAS AFFECTED BY THE STRONGEST WINDS (LOCALLY AS HIGH AS 55
MPH) WILL BE THE SANDIA AND MANZANO MOUNTAINS EAST TO THE CENTRAL
HIGHLANDS FROM SUNDAY MORNING THROUGH SUNDAY EVENING. AREAS OF SNOW
AND BLOWING SNOW WILL DEVELOP SUNDAY MORNING IN THESE SAME AREAS.
TEMPERATURES SUNDAY WILL BE MUCH COLDER...WITH HIGHS BELOW AVERAGE
FOR THE FIRST TIME THIS MONTH.
A TRANQUIL WEATHER PATTERN UNDER A HIGH PRESSURE RIDGE/SW FLOW ALOFT
WILL MOVE IN FOR MONDAY AND TUESDAY. VENTILATION RATES WILL DROP TO
POOR ALL AREAS MONDAY AS THE LOW LEVEL COLD AIR WILL BE SLOW TO
MODIFY AND WARMER AIR ALOFT MOVES OVERHEAD. VENT RATES IMPROVE
TUESDAY AS SOUTHWEST WINDS INCREASE SOMEWHAT.
THE NEXT PACIFIC TROUGH APPROACHES FROM THE WEST TUESDAY NIGHT. GFS
AND ECMWF IN GOOD AGREEMENT THROUGH WEDNESDAY...BRINGING SCATTERED
SNOW SHOWERS TO MUCH OF WESTERN AND NWRN NM DURING THE DAY WEDNESDAY
INTO WEDNESDAY NIGHT. VENTILATION RATES CONTINUE TO IMPROVE
WEDNESDAY AS COLDER AIR ALOFT ASSOCIATED WITH THE TROUGH MOVES OVER.
MODELS BEGIN TO DIVERGE LATE IN THE WEEK WITH REGARD TO HOW FAR
SOUTH A TRAILING SYSTEM WILL TRACK FOR THE LATTER HALF OF THE WORK
WEEK.
33
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ502>506.
WINTER WEATHER ADVISORY UNTIL 5 PM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ516>518-521>523.
WINTER STORM WARNING UNTIL 5 PM MST SUNDAY FOR THE FOLLOWING
ZONES...NMZ510>515.
WINTER WEATHER ADVISORY FROM 5 AM TO 5 PM MST SUNDAY FOR THE
FOLLOWING ZONES...NMZ527.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1102 PM MST FRI DEC 12 2014
.AVIATION...
06Z TAF CYCLE
RECENT METARS INDICATE LOW LEVEL MOISTURE IN THE PECOS RIVER
VALLEY IS INDEED RICH ENOUGH FOR LIFR CONDITIONS IN DENSE FOG TO
DEVELOP...DESPITE HIGH CLOUDS CROSSING THE AREA. THUS...LIKE THE
LAST 4 NIGHTS...KROW APPEARS DESTINED FOR ANOTHER FOG EVENT LATE
TONIGHT UNTIL MID MORNING SATURDAY. LIFR CONDITIONS IN FOG COULD
SPREAD AS FAR N AS DE BACA COUNTY AND EASTWARD ACROSS CURRY AND
ROOSEVELT COUNTIES. OTHERWISE...MODELS DEPICT SHOWERS MOVING
EASTWARD ACROSS THE AREA WEST OF THE CONTINENTAL DIVIDE IN THE
MORNING...THEN INTO THE CENTRAL VALLEY DURING THE AFTN. A PACIFIC
COLD FRONT SHOULD THEN INTENSIFY PCPN AND CAUSE AN ABRUPT WIND
SHIFT AS IT CROSSES WESTERN AREAS DURING THE AFTN...THEN CENTRAL
AREAS IN THE EVENING. THE SNOW LEVEL SHOULD FALL RAPIDLY TO AROUND
6K FT WITH THE PASSAGE OF THE FRONT. IFR AND MVFR CONDITIONS AND
MT OBSCURATIONS ARE EXPECTED WITH THE RAIN AND SNOW...ESPECIALLY
AS THE FRONT APPROACHES/CROSSES.
44
&&
.PREV DISCUSSION...922 PM MST FRI DEC 12 2014...
.UPDATE...
CONTINUED WITH MODIFICATIONS TO POP/WX...SNOW AMOUNTS INTO THE
SATURDAY NIGHT/SUNDAY PERIOD. OVERALL JUST RAISED POPS SOME MORE
WITH LATEST 00Z NAM AND BULK OF NUMERICAL GUIDANCE SHOWING A WELL-
DEFINED AREA OF MODERATE QPF MOVING OVER SATURDAY NIGHT. THE SANGRE
DE CRISTOS WILL LIKELY GET SLAMMED WITH UNSTABLE AND MOIST COLD
ADVECTION ON THE BACK SIDE OF THE DEPARTING WAVE. RAISED SNOWFALL
AMOUNTS THERE WITH THE POTENTIAL FOR OVER A FOOT ON W/NW SLOPES.
CONVERTED CONVECTIVE PRECIP OVER TO STRATIFORM RAIN/SNOW WORDING
SATURDAY NIGHT. THERE WILL BE INSTABILITY FOR TSTORMS BUT TOSSED
IT FROM GRIDS...EXCEPT THE FAR EAST...SINCE THAT WILL LIKELY NOT
BE THE MAIN IMPACT WX AND MADE FORECAST ELEMENTS FAR TOO COMPLEX.
TOYED WITH THE IDEA OF ADDING AREA AROUND TAOS TO THE WINTER STORM
WATCH BUT WAS NOT CONFIDENT ENOUGH AT THIS POINT. OVERNIGHT SHIFT
WILL HAVE A CLOSER LOOK ON THE REMAINDER OF MODEL TRENDS.
GUYER
&&
.PREV DISCUSSION...537 PM MST FRI DEC 12 2014...
.UPDATE...
MADE CHANGES TO POPS ACROSS WESTERN NM...SKY COVER ALL AREAS...AND
PATCHY FOG FOR EAST CENTRAL/SE PLAINS TONIGHT AND EARLY SATURDAY.
BASED ON LATEST WPC PROBABILISTIC POP GUIDANCE...LATEST MODELS...
INCLUDING HRRR AND WRF...REMOVED MOST CHANCES UNTIL WELL AFTER 06Z
FOR WESTERN NM. HRRR AVIATION IMPACT FIELDS SHOW YET ANOTHER AREA
OF LOW CLOUDS/FOG AS PATCHY HIGH CLOUDS CLEAR THE EAST OVERNIGHT.
WILL BE MAKING MORE CHANGES THROUGH THE EVENING FOR THE WEEKEND
AFTER NEW 00Z MODEL GUIDANCE ARRIVES.
GUYER
&&
.PREV DISCUSSION...317 PM MST FRI DEC 12 2014...
.SYNOPSIS...
A PACIFIC STORM CROSSING THE CALIFORNIA COAST WILL KNOCK ON THE
WESTERN DOOR OF NEW MEXICO SATURDAY MORNING...AND DELIVER A
WEEKEND PUNCH OF WATER AND WINTRY WEATHER ACROSS THE STATE. WITH
HEAVIEST SNOW OVER THE NORTHERN HIGH COUNTRY...AND SNOW COVERAGE
WIDESPREAD ACROSS THE REMAINDER OF NORTHERN...CENTRAL AND WESTERN
NEW MEXICO...CLEARING SKIES WILL WAIT UNTIL SUNDAY NIGHT BEFORE
SETTING UP SUNSHINE AND WARMING TEMPERATURES TO START THE WORK
WEEK. ANOTHER STORM IS DUE IN BY MIDWEEK TO KEEP STORMY WEATHER IN
THE FORECAST HEADING TOWARD NEXT WEEKEND.
&&
.DISCUSSION...
CURRENTLY...LARGE PACIFIC STORM SYSTEM EXTENDING FROM SOUTHEAST
ALASKA TO SOUTHERN CALIFORNIA AND THE BAJA PENINSULA HEADING EAST
TOWARD NEW MEXICO...AS SURFACE HIGH PRESSURE REMAINS PARKED IN
ADVANCE OVER THE FOUR CORNERS. STATIONARY FRONT FROM CENTRAL
MONTANA TO EASTERN COLORADO... AND ON ACROSS THE TEXAS
PANHANDLE...REMAINS CLEAR OF THE EASTERN NEW MEXICO BORDER. FOG
BURNED OFF BY LATE MORNING OVER THE EASTERN PLAINS...AS BANDS OF
CLOUD START TO WORK INTO WESTERN AND CENTRAL NEW MEXICO IN ADVANCE
OF THE WEST COAST SYSTEM.
MODELS...IN PRETTY DECENT AGREEMENT THROUGH THE UPCOMING WORK WEEK
AND INTO THE FOLLOWING PRE HOLIDAY WEEKEND. LARGE AMPLITUDE
WESTERN TROUGH AXIS WILL ENTER WESTERN NEW MEXICO BY TOMORROW
AFTERNOON...CLOSE OFF INTO A LOW OVER THE NORTHERN MOUNTAINS
SATURDAY NIGHT...AND THEN BOMB RAPIDLY OVER WESTERN OKLAHOMA
DURING THE DAY ON SUNDAY. WITH STRONG SYSTEM OUTCOME MOVING INTO
THE MIDWEST ON MONDAY...NORTHWEST FLOW WILL WORK IN OVER NEW
MEXICO AHEAD OF RIDGE FROM SOUTHERN ARIZONA TO CENTRAL BRITISH
COLUMBIA...AND THIS RIDGE WILL MOVE OVER NEW MEXICO ON
TUESDAY. NEXT UPSTREAM TROUGH DIGGING RAPIDLY FROM CLOSED LOW OVER
THE ALASKAN BERING SEA TO SOUTHERN CALIFORNIA AND NORTHERN MEXICO
WILL SHIFT EAST AND ENCROACH ON WESTERN NEW MEXICO BY
MIDWEEK...WITH THE STORM CORE OOZING EASTWARD ACROSS THE SOUTHERN
HALF OF THE STATE THURSDAY AND THURSDAY NIGHT. AS SYSTEM CORE
SLIDES OFF INTO NORTH CENTRAL TEXAS FRIDAY...NORTHWEST FLOW WILL
HELP BRING AN END TO THE WINTER WEATHER FRIDAY EVENING. TRAILING
RIDGE WILL AMPLIFY FROM NORTHERN MEXICO ACROSS NEW MEXICO TO THE
CANADIAN ARCTIC ON SATURDAY...AS NEXT INBOUND SYSTEM TAKES SHAPE
OVER THE CALIFORNIA SIERRA NEVADA COUNTRY SATURDAY NIGHT AND MOVES
INTO THE HEART OF ARIZONA ON SUNDAY.
OVERNIGHT...CLOUD COVER MOVING INTO WESTERN NEW MEXICO IN ADVANCE
OF NEXT INBOUND SYSTEM WILL KEEP OVERNIGHT TEMPERATURES A LITTLE
WARMER...WITH MOST SPOTS IN THE WEST RIGHT AROUND FREEZING...AND A
LITTLE WARMER WORKING SOUTH OF INTERSTATE 40. 20S WILL HOLD ON TO
THE NORTH...AS THE WEST WILL RUN MILD WITH LOWS IN THE 30S AND
40S. FIRST OF THE SHOWERS WILL CROSS OUT OF ARIZONA AND REACH THE
CONTINENTAL DIVIDE BY SUNRISE...BUT WARM TEMPERATURES WILL LIMIT
SNOW COVERAGE TO THE HIGH COUNTRY OF THE CHUSKAS...THE SOUTHWEST
MOUNTAINS...AND ALONG THE CONTINENTAL DIVIDE SUMMITS. FOG COVERAGE
IN THE EAST AND SOUTH SHOULD BE REDUCED IN COVERAGE
OVERNIGHT...WITH EASTERN CHAVES AND SOUTHERN ROOSEVELT COUNTY MOST
LIKELY FOR SOME REDUCED VISIBILITIES. WITH REDUCED COVERAGE...HAVE
HELD OFF ON A FIRST STRIKE DENSE FOG ADVISORY...AND WILL SEE HOW
THINGS GO THIS EVENING.
FOR SATURDAY...KNOCK A FEW DEGREES OFF THE DAYTIME HIGHS AND MOVE
THE TROUGH AXIS INTO WESTERN NEW MEXICO...AND RAIN AND HIGH
COUNTRY SNOW COVERAGE WILL EXPAND ACROSS THE NORTH...BLANKET THE
WEST...AND REACH ACROSS THE RIO GRANDE TO THE CENTRAL MOUNTAINS BY
SATURDAY AFTERNOON. DESPITE THE HARBINGER OF WINTRY
WEATHER...DAYTIME HIGH TEMPERATURES WILL RUN IN DOUBLE DIGITS
ABOVE NORMAL IN THE EAST...WHILE REMAINING 3 TO 8 DEGREES ABOVE
NORMAL IN THE WEST. PATTERN WILL KEEP SNOW IN THE HIGH COUNTRY FOR
MUCH OF THE DAY...WITH ACCUMULATIONS RUNNING A COUPLE OF INCHES
NORTH AND WEST...AND A DUSTING TO AN INCH OR SO SHOWING UP ON THE
MID SLOPES BY SATURDAY AFTERNOON. CURRENT WINTER STORM WATCH
CONTINUES TO LOOK GOOD...AND WILL EXPLORE ACCUMULATIONS BETWEEN
THE JEMEZ...SAN JUAN...AND TUSAS MOUNTAINS AND THE SANGRE DE
CRISTO MOUNTAINS TO SEE IF ADDITIONAL WINTER STATEMENTS ARE NEEDED
FOR THE SPOTS BETWEEN. WARMER TEMPERATURES IN PLAY MAY LIMIT
ACCUMULATIONS OVER THE SANDIA AND MANZANO MOUNTAINS FOR NOW...BUT
THESE SPOTS COULD BECOME BIGGER PLAYERS SATURDAY NIGHT. AS CLOSED
LOW MOVES ACROSS THE FOUR CORNERS IN NEGATIVE TILT...AND SOLID
DYNAMICS SHOW UP IN THE IMMEDIATE BASE OF THE TROUGH...SNOW
COVERAGE HEART WILL SHIFT ACROSS CENTRAL NEW MEXICO HEADING INTO
SUNDAY MORNING...AND COLDER AIR WILL HELP SNOW COVERAGE DEVELOP
ACROSS SOUTHERN PORTIONS OF THE FORECAST AREA...WITH MOST SPOTS
EAST OF THE CENTRAL MOUNTAINS REMAINING IN THE RAIN OVERNIGHT.
WINDS WILL BE BREEZY IN SPOTS SATURDAY DAYTIME OVER THE EAST...AND
OVER THE SOUTH...BUT ANY BLOWING SNOW ISSUES SHOULD BE LOCALIZED
THROUGH MUCH OF SATURDAY NIGHT INTO SUNDAY MORNING.
FOR SUNDAY...BOMBING CLOSED LOW SHIFTING TO NORTHEAST NEW MEXICO
AND POISED TO CROSS INTO WESTERN KANSAS...AS SURFACE LOW DEEPENS
RAPIDLY OVER THE EASTERN PORTIONS OF THE OKLAHOMA PANHANDLE. MUCH
COLDER TEMPERATURES WILL BRING MOST SPOTS 3 TO 8 DEGREES BELOW MID
DECEMBER NORMALS...WITH TEMPERATURES CLOSER TO NORMAL OVER THE
EXTREME EAST. STORM FOCUS WILL SHIFT OUT OF THE WEST AND CENTRAL
AND INTO THE NORTH AND NORTHEAST SUNDAY DAYTIME WITH CONTINUED
SIGNIFICANT ACCUMULATION OVER THE SANGRE DE CRISTO RANGE...WITH
COVERAGE EXPANDING EASTWARD ALONG RATON RIDGE AND ACROSS JOHNSON
MESA ALONG THE COLORADO LINE NEAR INTERSTATE 25. SNOWFALL WILL
START TAPERING OFF ELSEWHERE. AS WINDS SHIFT TO THE NORTHWEST IN
THE WAKE OF THE DEPARTING SYSTEM...CONDITIONS WILL BECOME BREEZY
ACROSS THE CONTINENTAL DIVIDE...AND ACROSS THE CENTRAL MOUNTAINS
AND ADJACENT EASTERN PLAINS THROUGH SUNDAY AFTERNOON. LAST OF THE
SNOW WILL TAPER OFF SUNDAY NIGHT OVER THE SANGRE DE CRISTOS AND
RATON RIDGE AS WIND SPEEDS DROP OFF AFTER MIDNIGHT.
FOR MONDAY...DEPARTING STORM WILL ALLOW RIDGE FROM CHIHUAHUA
ACROSS ARIZONA TO THE GREAT SALT LAKE TO START BUILDING TOWARD NEW
MEXICO. WARMING WILL PUSH TEMPERATURES BACK UP TO WITHIN A FEW
DEGREES EITHER SIDE OF NORMAL...AS SURFACE WINDS CALM DOWN IN A
VERY WEAK SURFACE PRESSURE GRADIENT UNDER THE RIDGE. FIRST SIGNS
OF TRAILING COLD FRONT WILL TAG THE EASTERN TIER OF THE STATE LATE
MONDAY AFTERNOON...LIMITING RECOVERY FROM COOLER WEEKEND
TEMPERATURES.
OUTLOOK...TUESDAY THROUGH THURSDAY...RIDGE SHEARING EASTWARD
ACROSS THE STATE EARLY ON TUESDAY WILL MAKE ROOM FOR NEXT PACIFIC
SYSTEM WHICH WILL WORK INTO WESTERN NEW MEXICO TUESDAY NIGHT.
TUESDAY NIGHT WESTERN AND NORTHWESTERN SNOW WILL OVERSPREAD MUCH
OF THE WEST AND CENTRAL AS MOSTLY RAIN WITH HIGH COUNTRY SNOW ON
WEDNESDAY...AND CONTINUING IN A NIGHTTIME SNOW...DAYTIME RAIN
PATTERN THROUGH THURSDAY NIGHT AS THE NEXT SYSTEM IN LINE WORKS
INTO WESTERN NEW MEXICO ON THURSDAY FOR ITS TRIP EAST. GRADUAL
COOLING TREND WILL BRING MIDWEEK TEMPERATURES DOWN TO A FEW
DEGREES BELOW MID DECEMBER NORMALS...BUT THIS PACIFIC SYSTEM WILL
NOT CARRY THE COLD AIR MUCH AS ITS PREDECESSOR IN THE PREVIOUS
STORM. SYSTEM WILL ALSO HAVE MUCH LESS SURFACE INTENSITY...AS
SURFACE LOW DEEPENING OVER THE OKLAHOMA PANHANDLE WEDNESDAY WILL
EJECT EASTWARD WEDNESDAY NIGHT...RELAXING FORCING FOR
SURFACE WINDS ACROSS THE MIDPOINT OF THE WORK WEEK.
SHY
&&
.FIRE WEATHER...
UNSETTLED WEATHER WITH RAIN/SNOW EXPECTED FOR THIS
WEEKEND...PRIMARILY SATURDAY NIGHT INTO SUNDAY. ANOTHER WETTING
SYSTEM POSSIBLE MIDWEEK.
AS THE RIDGE AXIS SHIFTS EAST...HIGH CLOUDS WILL INCREASE ALONG WITH
SOUTHWEST FLOW OVERNIGHT INTO SATURDAY ACROSS THE EAST CENTRAL
PLAINS. OVERNIGHT RH RECOVERIES WILL BE EXCELLENT ACROSS WESTERN AND
CENTRAL AREAS...GOOD TO FAIR EAST OF THE CENTRAL MOUNTAIN CHAIN.
TEMPERATURES WILL START COOLING SATURDAY AS THE PACIFIC LOW
APPROACHES THE STATE FROM THE WEST. THE WEST WILL SEE WETTING
PRECIPITATION IN THE FORM OF LOW ELEVATION RAIN...HIGH ELEVATION/MOUNTAIN
SNOW. WINDS WILL BE BREEZY TO GUSTY OUT OF THE SOUTH TO
SOUTHWEST...WITH GUSTIER WINDS ACROSS THE EAST CENTRAL PLAINS.
VENTILATION RATES WILL IMPROVE ACROSS WESTERN AND CENTRAL AREA.
DESPITE THE GUSTIER WINDS...HUMIDITY READINGS WILL REMAIN ABOVE
CRITICAL LEVELS.
SATURDAY NIGHT INTO SUNDAY MORNING...NORTHERN AND CENTRAL AREAS WILL
SEE RAIN/SNOW SHOWERS AS THE COLD FRONT PUSHES EAST. SNOW
ACCUMULATIONS WILL BE GREATER ALONG THE HIGHER ELEVATIONS. SNOW
LEVELS WILL BE MUCH LOWER WITH THIS SYSTEM THE PAST FEW.
TEMPERATURES WILL FALL BELOW NORMAL WITH COOLER AIR COMING IN ON
SUNDAY. EXPECT CONTINUED GOOD TO EXCELLENT VENTILATION RATES MOST
AREAS ON SUNDAY. WINDS WILL CONTINUE TO BE STRONG ACROSS THE EAST
CENTRAL PLAINS. DURING SUNDAY NIGHT...THE STORM WILL EXIT TO THE
NORTHEAST WITH WRAP WETTING PRECIPITATION AND COOLER AIR ACROSS NORTH
CENTRAL AND NORTHEAST AREAS.
TEMPERATURES IN THE WEST WILL REBOUND TO NEAR NORMAL WITH POOR
VENTILATION AREA WIDE AS AN UPPER LEVEL RIDGE BUILDS OVER THE
REGION. AFTER MONDAY...WE BEGIN TO SEE ROLLER COASTER VENTILATION
RATES AS MODELS BEGIN TO PICK UP ANOTHER APPROACHING PACIFIC STORM
SYSTEM BY MIDWEEK AND ANOTHER FOR THE FOLLOWING WEEKEND. ECMWF IS
MORE BULLISH ON WETTER CONDITIONS THAN THE GFS DURING THE MIDWEEK
PERIOD. CONFIDENCE IS PRETTY HIGH FOR ANOTHER WETTING EVENT MIDWEEK
AND MODERATE FOR THE FOLLOWING WEEKEND.
CML
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY AFTERNOON
FOR THE FOLLOWING ZONES...NMZ510>515-521.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
922 PM MST FRI DEC 12 2014
.UPDATE...
CONTINUED WITH MODIFICATIONS TO POP/WX...SNOW AMOUNTS INTO THE
SATURDAY NIGHT/SUNDAY PERIOD. OVERALL JUST RAISED POPS SOME MORE
WITH LATEST 00Z NAM AND BULK OF NUMERICAL GUIDANCE SHOWING A WELL-
DEFINED AREA OF MODERATE QPF MOVING OVER SATURDAY NIGHT. THE SANGRE
DE CRISTOS WILL LIKELY GET SLAMMED WITH UNSTABLE AND MOIST COLD
ADVECTION ON THE BACK SIDE OF THE DEPARTING WAVE. RAISED SNOWFALL
AMOUNTS THERE WITH THE POTENTIAL FOR OVER A FOOT ON W/NW SLOPES.
CONVERTED CONVECTIVE PRECIP OVER TO STRATIFORM RAIN/SNOW WORDING
SATURDAY NIGHT. THERE WILL BE INSTABILITY FOR TSTORMS BUT TOSSED
IT FROM GRIDS...EXCEPT THE FAR EAST...SINCE THAT WILL LIKELY NOT
BE THE MAIN IMPACT WX AND MADE FORECAST ELEMENTS FAR TOO COMPLEX.
TOYED WITH THE IDEA OF ADDING AREA AROUND TAOS TO THE WINTER STORM
WATCH BUT WAS NOT CONFIDENT ENOUGH AT THIS POINT. OVERNIGHT SHIFT
WILL HAVE A CLOSER LOOK ON THE REMAINDER OF MODEL TRENDS.
GUYER
&&
.PREV DISCUSSION...537 PM MST FRI DEC 12 2014...
.UPDATE...
MADE CHANGES TO POPS ACROSS WESTERN NM...SKY COVER ALL AREAS...AND
PATCHY FOG FOR EAST CENTRAL/SE PLAINS TONIGHT AND EARLY SATURDAY.
BASED ON LATEST WPC PROBABILISTIC POP GUIDANCE...LATEST MODELS...
INCLUDING HRRR AND WRF...REMOVED MOST CHANCES UNTIL WELL AFTER 06Z
FOR WESTERN NM. HRRR AVIATION IMPACT FIELDS SHOW YET ANOTHER AREA
OF LOW CLOUDS/FOG AS PATCHY HIGH CLOUDS CLEAR THE EAST OVERNIGHT.
WILL BE MAKING MORE CHANGES THROUGH THE EVENING FOR THE WEEKEND
AFTER NEW 00Z MODEL GUIDANCE ARRIVES.
GUYER
&&
.PREV DISCUSSION...500 PM MST FRI DEC 12 2014...
.AVIATION...
00Z TAF CYCLE
LIKE THE LAST 4 NIGHTS...THE POTENTIAL EXISTS FOR IFR CONDITIONS
IN LOW CLOUDS AND FOG TO REDEVELOP ALONG AND E OF THE PECOS RIVER
AND FROM THE CAPROCK SOUTHWARD TONIGHT. SHEETS OF HIGH CLOUDS
CROSSING WILL LIMIT RADIATIONAL COOLING...WHICH SHOULD PREVENT THE
EXTENSIVE LIFR OUTBREAK SEEN IN THIS AREA LAST NIGHT. HOWEVER...
THE CONDENSATION SHOULD CREEP BACK UP THE PECOS RIVER VALLEY AND
MAY IMPACT KROW AS EARLY AS 05Z. OTHERWISE...MODELS DEPICT A
PACIFIC COLD FRONT USHERING RAIN AND SNOW AS IT ARRIVES IN
LOCATIONS W OF THE CONTINENTAL DIVIDE SATURDAY AFTN.
44
&&
.PREV DISCUSSION...317 PM MST FRI DEC 12 2014...
.SYNOPSIS...
A PACIFIC STORM CROSSING THE CALIFORNIA COAST WILL KNOCK ON THE
WESTERN DOOR OF NEW MEXICO SATURDAY MORNING...AND DELIVER A
WEEKEND PUNCH OF WATER AND WINTRY WEATHER ACROSS THE STATE. WITH
HEAVIEST SNOW OVER THE NORTHERN HIGH COUNTRY...AND SNOW COVERAGE
WIDESPREAD ACROSS THE REMAINDER OF NORTHERN...CENTRAL AND WESTERN
NEW MEXICO...CLEARING SKIES WILL WAIT UNTIL SUNDAY NIGHT BEFORE
SETTING UP SUNSHINE AND WARMING TEMPERATURES TO START THE WORK
WEEK. ANOTHER STORM IS DUE IN BY MIDWEEK TO KEEP STORMY WEATHER IN
THE FORECAST HEADING TOWARD NEXT WEEKEND.
&&
.DISCUSSION...
CURRENTLY...LARGE PACIFIC STORM SYSTEM EXTENDING FROM SOUTHEAST
ALASKA TO SOUTHERN CALIFORNIA AND THE BAJA PENINSULA HEADING EAST
TOWARD NEW MEXICO...AS SURFACE HIGH PRESSURE REMAINS PARKED IN
ADVANCE OVER THE FOUR CORNERS. STATIONARY FRONT FROM CENTRAL
MONTANA TO EASTERN COLORADO... AND ON ACROSS THE TEXAS
PANHANDLE...REMAINS CLEAR OF THE EASTERN NEW MEXICO BORDER. FOG
BURNED OFF BY LATE MORNING OVER THE EASTERN PLAINS...AS BANDS OF
CLOUD START TO WORK INTO WESTERN AND CENTRAL NEW MEXICO IN ADVANCE
OF THE WEST COAST SYSTEM.
MODELS...IN PRETTY DECENT AGREEMENT THROUGH THE UPCOMING WORK WEEK
AND INTO THE FOLLOWING PRE HOLIDAY WEEKEND. LARGE AMPLITUDE
WESTERN TROUGH AXIS WILL ENTER WESTERN NEW MEXICO BY TOMORROW
AFTERNOON...CLOSE OFF INTO A LOW OVER THE NORTHERN MOUNTAINS
SATURDAY NIGHT...AND THEN BOMB RAPIDLY OVER WESTERN OKLAHOMA
DURING THE DAY ON SUNDAY. WITH STRONG SYSTEM OUTCOME MOVING INTO
THE MIDWEST ON MONDAY...NORTHWEST FLOW WILL WORK IN OVER NEW
MEXICO AHEAD OF RIDGE FROM SOUTHERN ARIZONA TO CENTRAL BRITISH
COLUMBIA...AND THIS RIDGE WILL MOVE OVER NEW MEXICO ON
TUESDAY. NEXT UPSTREAM TROUGH DIGGING RAPIDLY FROM CLOSED LOW OVER
THE ALASKAN BERING SEA TO SOUTHERN CALIFORNIA AND NORTHERN MEXICO
WILL SHIFT EAST AND ENCROACH ON WESTERN NEW MEXICO BY
MIDWEEK...WITH THE STORM CORE OOZING EASTWARD ACROSS THE SOUTHERN
HALF OF THE STATE THURSDAY AND THURSDAY NIGHT. AS SYSTEM CORE
SLIDES OFF INTO NORTH CENTRAL TEXAS FRIDAY...NORTHWEST FLOW WILL
HELP BRING AN END TO THE WINTER WEATHER FRIDAY EVENING. TRAILING
RIDGE WILL AMPLIFY FROM NORTHERN MEXICO ACROSS NEW MEXICO TO THE
CANADIAN ARCTIC ON SATURDAY...AS NEXT INBOUND SYSTEM TAKES SHAPE
OVER THE CALIFORNIA SIERRA NEVADA COUNTRY SATURDAY NIGHT AND MOVES
INTO THE HEART OF ARIZONA ON SUNDAY.
OVERNIGHT...CLOUD COVER MOVING INTO WESTERN NEW MEXICO IN ADVANCE
OF NEXT INBOUND SYSTEM WILL KEEP OVERNIGHT TEMPERATURES A LITTLE
WARMER...WITH MOST SPOTS IN THE WEST RIGHT AROUND FREEZING...AND A
LITTLE WARMER WORKING SOUTH OF INTERSTATE 40. 20S WILL HOLD ON TO
THE NORTH...AS THE WEST WILL RUN MILD WITH LOWS IN THE 30S AND
40S. FIRST OF THE SHOWERS WILL CROSS OUT OF ARIZONA AND REACH THE
CONTINENTAL DIVIDE BY SUNRISE...BUT WARM TEMPERATURES WILL LIMIT
SNOW COVERAGE TO THE HIGH COUNTRY OF THE CHUSKAS...THE SOUTHWEST
MOUNTAINS...AND ALONG THE CONTINENTAL DIVIDE SUMMITS. FOG COVERAGE
IN THE EAST AND SOUTH SHOULD BE REDUCED IN COVERAGE
OVERNIGHT...WITH EASTERN CHAVES AND SOUTHERN ROOSEVELT COUNTY MOST
LIKELY FOR SOME REDUCED VISIBILITIES. WITH REDUCED COVERAGE...HAVE
HELD OFF ON A FIRST STRIKE DENSE FOG ADVISORY...AND WILL SEE HOW
THINGS GO THIS EVENING.
FOR SATURDAY...KNOCK A FEW DEGREES OFF THE DAYTIME HIGHS AND MOVE
THE TROUGH AXIS INTO WESTERN NEW MEXICO...AND RAIN AND HIGH
COUNTRY SNOW COVERAGE WILL EXPAND ACROSS THE NORTH...BLANKET THE
WEST...AND REACH ACROSS THE RIO GRANDE TO THE CENTRAL MOUNTAINS BY
SATURDAY AFTERNOON. DESPITE THE HARBINGER OF WINTRY
WEATHER...DAYTIME HIGH TEMPERATURES WILL RUN IN DOUBLE DIGITS
ABOVE NORMAL IN THE EAST...WHILE REMAINING 3 TO 8 DEGREES ABOVE
NORMAL IN THE WEST. PATTERN WILL KEEP SNOW IN THE HIGH COUNTRY FOR
MUCH OF THE DAY...WITH ACCUMULATIONS RUNNING A COUPLE OF INCHES
NORTH AND WEST...AND A DUSTING TO AN INCH OR SO SHOWING UP ON THE
MID SLOPES BY SATURDAY AFTERNOON. CURRENT WINTER STORM WATCH
CONTINUES TO LOOK GOOD...AND WILL EXPLORE ACCUMULATIONS BETWEEN
THE JEMEZ...SAN JUAN...AND TUSAS MOUNTAINS AND THE SANGRE DE
CRISTO MOUNTAINS TO SEE IF ADDITIONAL WINTER STATEMENTS ARE NEEDED
FOR THE SPOTS BETWEEN. WARMER TEMPERATURES IN PLAY MAY LIMIT
ACCUMULATIONS OVER THE SANDIA AND MANZANO MOUNTAINS FOR NOW...BUT
THESE SPOTS COULD BECOME BIGGER PLAYERS SATURDAY NIGHT. AS CLOSED
LOW MOVES ACROSS THE FOUR CORNERS IN NEGATIVE TILT...AND SOLID
DYNAMICS SHOW UP IN THE IMMEDIATE BASE OF THE TROUGH...SNOW
COVERAGE HEART WILL SHIFT ACROSS CENTRAL NEW MEXICO HEADING INTO
SUNDAY MORNING...AND COLDER AIR WILL HELP SNOW COVERAGE DEVELOP
ACROSS SOUTHERN PORTIONS OF THE FORECAST AREA...WITH MOST SPOTS
EAST OF THE CENTRAL MOUNTAINS REMAINING IN THE RAIN OVERNIGHT.
WINDS WILL BE BREEZY IN SPOTS SATURDAY DAYTIME OVER THE EAST...AND
OVER THE SOUTH...BUT ANY BLOWING SNOW ISSUES SHOULD BE LOCALIZED
THROUGH MUCH OF SATURDAY NIGHT INTO SUNDAY MORNING.
FOR SUNDAY...BOMBING CLOSED LOW SHIFTING TO NORTHEAST NEW MEXICO
AND POISED TO CROSS INTO WESTERN KANSAS...AS SURFACE LOW DEEPENS
RAPIDLY OVER THE EASTERN PORTIONS OF THE OKLAHOMA PANHANDLE. MUCH
COLDER TEMPERATURES WILL BRING MOST SPOTS 3 TO 8 DEGREES BELOW MID
DECEMBER NORMALS...WITH TEMPERATURES CLOSER TO NORMAL OVER THE
EXTREME EAST. STORM FOCUS WILL SHIFT OUT OF THE WEST AND CENTRAL
AND INTO THE NORTH AND NORTHEAST SUNDAY DAYTIME WITH CONTINUED
SIGNIFICANT ACCUMULATION OVER THE SANGRE DE CRISTO RANGE...WITH
COVERAGE EXPANDING EASTWARD ALONG RATON RIDGE AND ACROSS JOHNSON
MESA ALONG THE COLORADO LINE NEAR INTERSTATE 25. SNOWFALL WILL
START TAPERING OFF ELSEWHERE. AS WINDS SHIFT TO THE NORTHWEST IN
THE WAKE OF THE DEPARTING SYSTEM...CONDITIONS WILL BECOME BREEZY
ACROSS THE CONTINENTAL DIVIDE...AND ACROSS THE CENTRAL MOUNTAINS
AND ADJACENT EASTERN PLAINS THROUGH SUNDAY AFTERNOON. LAST OF THE
SNOW WILL TAPER OFF SUNDAY NIGHT OVER THE SANGRE DE CRISTOS AND
RATON RIDGE AS WIND SPEEDS DROP OFF AFTER MIDNIGHT.
FOR MONDAY...DEPARTING STORM WILL ALLOW RIDGE FROM CHIHUAHUA
ACROSS ARIZONA TO THE GREAT SALT LAKE TO START BUILDING TOWARD NEW
MEXICO. WARMING WILL PUSH TEMPERATURES BACK UP TO WITHIN A FEW
DEGREES EITHER SIDE OF NORMAL...AS SURFACE WINDS CALM DOWN IN A
VERY WEAK SURFACE PRESSURE GRADIENT UNDER THE RIDGE. FIRST SIGNS
OF TRAILING COLD FRONT WILL TAG THE EASTERN TIER OF THE STATE LATE
MONDAY AFTERNOON...LIMITING RECOVERY FROM COOLER WEEKEND
TEMPERATURES.
OUTLOOK...TUESDAY THROUGH THURSDAY...RIDGE SHEARING EASTWARD
ACROSS THE STATE EARLY ON TUESDAY WILL MAKE ROOM FOR NEXT PACIFIC
SYSTEM WHICH WILL WORK INTO WESTERN NEW MEXICO TUESDAY NIGHT.
TUESDAY NIGHT WESTERN AND NORTHWESTERN SNOW WILL OVERSPREAD MUCH
OF THE WEST AND CENTRAL AS MOSTLY RAIN WITH HIGH COUNTRY SNOW ON
WEDNESDAY...AND CONTINUING IN A NIGHTTIME SNOW...DAYTIME RAIN
PATTERN THROUGH THURSDAY NIGHT AS THE NEXT SYSTEM IN LINE WORKS
INTO WESTERN NEW MEXICO ON THURSDAY FOR ITS TRIP EAST. GRADUAL
COOLING TREND WILL BRING MIDWEEK TEMPERATURES DOWN TO A FEW
DEGREES BELOW MID DECEMBER NORMALS...BUT THIS PACIFIC SYSTEM WILL
NOT CARRY THE COLD AIR MUCH AS ITS PREDECESSOR IN THE PREVIOUS
STORM. SYSTEM WILL ALSO HAVE MUCH LESS SURFACE INTENSITY...AS
SURFACE LOW DEEPENING OVER THE OKLAHOMA PANHANDLE WEDNESDAY WILL
EJECT EASTWARD WEDNESDAY NIGHT...RELAXING FORCING FOR
SURFACE WINDS ACROSS THE MIDPOINT OF THE WORK WEEK.
SHY
&&
.FIRE WEATHER...
UNSETTLED WEATHER WITH RAIN/SNOW EXPECTED FOR THIS
WEEKEND...PRIMARILY SATURDAY NIGHT INTO SUNDAY. ANOTHER WETTING
SYSTEM POSSIBLE MIDWEEK.
AS THE RIDGE AXIS SHIFTS EAST...HIGH CLOUDS WILL INCREASE ALONG WITH
SOUTHWEST FLOW OVERNIGHT INTO SATURDAY ACROSS THE EAST CENTRAL
PLAINS. OVERNIGHT RH RECOVERIES WILL BE EXCELLENT ACROSS WESTERN AND
CENTRAL AREAS...GOOD TO FAIR EAST OF THE CENTRAL MOUNTAIN CHAIN.
TEMPERATURES WILL START COOLING SATURDAY AS THE PACIFIC LOW
APPROACHES THE STATE FROM THE WEST. THE WEST WILL SEE WETTING
PRECIPITATION IN THE FORM OF LOW ELEVATION RAIN...HIGH ELEVATION/MOUNTAIN
SNOW. WINDS WILL BE BREEZY TO GUSTY OUT OF THE SOUTH TO
SOUTHWEST...WITH GUSTIER WINDS ACROSS THE EAST CENTRAL PLAINS.
VENTILATION RATES WILL IMPROVE ACROSS WESTERN AND CENTRAL AREA.
DESPITE THE GUSTIER WINDS...HUMIDITY READINGS WILL REMAIN ABOVE
CRITICAL LEVELS.
SATURDAY NIGHT INTO SUNDAY MORNING...NORTHERN AND CENTRAL AREAS WILL
SEE RAIN/SNOW SHOWERS AS THE COLD FRONT PUSHES EAST. SNOW
ACCUMULATIONS WILL BE GREATER ALONG THE HIGHER ELEVATIONS. SNOW
LEVELS WILL BE MUCH LOWER WITH THIS SYSTEM THE PAST FEW.
TEMPERATURES WILL FALL BELOW NORMAL WITH COOLER AIR COMING IN ON
SUNDAY. EXPECT CONTINUED GOOD TO EXCELLENT VENTILATION RATES MOST
AREAS ON SUNDAY. WINDS WILL CONTINUE TO BE STRONG ACROSS THE EAST
CENTRAL PLAINS. DURING SUNDAY NIGHT...THE STORM WILL EXIT TO THE
NORTHEAST WITH WRAP WETTING PRECIPITATION AND COOLER AIR ACROSS NORTH
CENTRAL AND NORTHEAST AREAS.
TEMPERATURES IN THE WEST WILL REBOUND TO NEAR NORMAL WITH POOR
VENTILATION AREA WIDE AS AN UPPER LEVEL RIDGE BUILDS OVER THE
REGION. AFTER MONDAY...WE BEGIN TO SEE ROLLER COASTER VENTILATION
RATES AS MODELS BEGIN TO PICK UP ANOTHER APPROACHING PACIFIC STORM
SYSTEM BY MIDWEEK AND ANOTHER FOR THE FOLLOWING WEEKEND. ECMWF IS
MORE BULLISH ON WETTER CONDITIONS THAN THE GFS DURING THE MIDWEEK
PERIOD. CONFIDENCE IS PRETTY HIGH FOR ANOTHER WETTING EVENT MIDWEEK
AND MODERATE FOR THE FOLLOWING WEEKEND.
CML
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY AFTERNOON
FOR THE FOLLOWING ZONES...NMZ510>515-521.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
537 PM MST FRI DEC 12 2014
.UPDATE...
MADE CHANGES TO POPS ACROSS WESTERN NM...SKY COVER ALL AREAS...AND
PATCHY FOG FOR EAST CENTRAL/SE PLAINS TONIGHT AND EARLY SATURDAY.
BASED ON LATEST WPC PROBABILISTIC POP GUIDANCE...LATEST MODELS...
INCLUDING HRRR AND WRF...REMOVED MOST CHANCES UNTIL WELL AFTER 06Z
FOR WESTERN NM. HRRR AVIATION IMPACT FIELDS SHOW YET ANOTHER AREA
OF LOW CLOUDS/FOG AS PATCHY HIGH CLOUDS CLEAR THE EAST OVERNIGHT.
WILL BE MAKING MORE CHANGES THROUGH THE EVENING FOR THE WEEKEND
AFTER NEW 00Z MODEL GUIDANCE ARRIVES.
GUYER
&&
.PREV DISCUSSION...500 PM MST FRI DEC 12 2014...
.AVIATION...
00Z TAF CYCLE
LIKE THE LAST 4 NIGHTS...THE POTENTIAL EXISTS FOR IFR CONDITIONS
IN LOW CLOUDS AND FOG TO REDEVELOP ALONG AND E OF THE PECOS RIVER
AND FROM THE CAPROCK SOUTHWARD TONIGHT. SHEETS OF HIGH CLOUDS
CROSSING WILL LIMIT RADIATIONAL COOLING...WHICH SHOULD PREVENT THE
EXTENSIVE LIFR OUTBREAK SEEN IN THIS AREA LAST NIGHT. HOWEVER...
THE CONDENSATION SHOULD CREEP BACK UP THE PECOS RIVER VALLEY AND
MAY IMPACT KROW AS EARLY AS 05Z. OTHERWISE...MODELS DEPICT A
PACIFIC COLD FRONT USHERING RAIN AND SNOW AS IT ARRIVES IN
LOCATIONS W OF THE CONTINENTAL DIVIDE SATURDAY AFTN.
44
&&
.PREV DISCUSSION...317 PM MST FRI DEC 12 2014...
.SYNOPSIS...
A PACIFIC STORM CROSSING THE CALIFORNIA COAST WILL KNOCK ON THE
WESTERN DOOR OF NEW MEXICO SATURDAY MORNING...AND DELIVER A
WEEKEND PUNCH OF WATER AND WINTRY WEATHER ACROSS THE STATE. WITH
HEAVIEST SNOW OVER THE NORTHERN HIGH COUNTRY...AND SNOW COVERAGE
WIDESPREAD ACROSS THE REMAINDER OF NORTHERN...CENTRAL AND WESTERN
NEW MEXICO...CLEARING SKIES WILL WAIT UNTIL SUNDAY NIGHT BEFORE
SETTING UP SUNSHINE AND WARMING TEMPERATURES TO START THE WORK
WEEK. ANOTHER STORM IS DUE IN BY MIDWEEK TO KEEP STORMY WEATHER IN
THE FORECAST HEADING TOWARD NEXT WEEKEND.
&&
.DISCUSSION...
CURRENTLY...LARGE PACIFIC STORM SYSTEM EXTENDING FROM SOUTHEAST
ALASKA TO SOUTHERN CALIFORNIA AND THE BAJA PENINSULA HEADING EAST
TOWARD NEW MEXICO...AS SURFACE HIGH PRESSURE REMAINS PARKED IN
ADVANCE OVER THE FOUR CORNERS. STATIONARY FRONT FROM CENTRAL
MONTANA TO EASTERN COLORADO... AND ON ACROSS THE TEXAS
PANHANDLE...REMAINS CLEAR OF THE EASTERN NEW MEXICO BORDER. FOG
BURNED OFF BY LATE MORNING OVER THE EASTERN PLAINS...AS BANDS OF
CLOUD START TO WORK INTO WESTERN AND CENTRAL NEW MEXICO IN ADVANCE
OF THE WEST COAST SYSTEM.
MODELS...IN PRETTY DECENT AGREEMENT THROUGH THE UPCOMING WORK WEEK
AND INTO THE FOLLOWING PRE HOLIDAY WEEKEND. LARGE AMPLITUDE
WESTERN TROUGH AXIS WILL ENTER WESTERN NEW MEXICO BY TOMORROW
AFTERNOON...CLOSE OFF INTO A LOW OVER THE NORTHERN MOUNTAINS
SATURDAY NIGHT...AND THEN BOMB RAPIDLY OVER WESTERN OKLAHOMA
DURING THE DAY ON SUNDAY. WITH STRONG SYSTEM OUTCOME MOVING INTO
THE MIDWEST ON MONDAY...NORTHWEST FLOW WILL WORK IN OVER NEW
MEXICO AHEAD OF RIDGE FROM SOUTHERN ARIZONA TO CENTRAL BRITISH
COLUMBIA...AND THIS RIDGE WILL MOVE OVER NEW MEXICO ON
TUESDAY. NEXT UPSTREAM TROUGH DIGGING RAPIDLY FROM CLOSED LOW OVER
THE ALASKAN BERING SEA TO SOUTHERN CALIFORNIA AND NORTHERN MEXICO
WILL SHIFT EAST AND ENCROACH ON WESTERN NEW MEXICO BY
MIDWEEK...WITH THE STORM CORE OOZING EASTWARD ACROSS THE SOUTHERN
HALF OF THE STATE THURSDAY AND THURSDAY NIGHT. AS SYSTEM CORE
SLIDES OFF INTO NORTH CENTRAL TEXAS FRIDAY...NORTHWEST FLOW WILL
HELP BRING AN END TO THE WINTER WEATHER FRIDAY EVENING. TRAILING
RIDGE WILL AMPLIFY FROM NORTHERN MEXICO ACROSS NEW MEXICO TO THE
CANADIAN ARCTIC ON SATURDAY...AS NEXT INBOUND SYSTEM TAKES SHAPE
OVER THE CALIFORNIA SIERRA NEVADA COUNTRY SATURDAY NIGHT AND MOVES
INTO THE HEART OF ARIZONA ON SUNDAY.
OVERNIGHT...CLOUD COVER MOVING INTO WESTERN NEW MEXICO IN ADVANCE
OF NEXT INBOUND SYSTEM WILL KEEP OVERNIGHT TEMPERATURES A LITTLE
WARMER...WITH MOST SPOTS IN THE WEST RIGHT AROUND FREEZING...AND A
LITTLE WARMER WORKING SOUTH OF INTERSTATE 40. 20S WILL HOLD ON TO
THE NORTH...AS THE WEST WILL RUN MILD WITH LOWS IN THE 30S AND
40S. FIRST OF THE SHOWERS WILL CROSS OUT OF ARIZONA AND REACH THE
CONTINENTAL DIVIDE BY SUNRISE...BUT WARM TEMPERATURES WILL LIMIT
SNOW COVERAGE TO THE HIGH COUNTRY OF THE CHUSKAS...THE SOUTHWEST
MOUNTAINS...AND ALONG THE CONTINENTAL DIVIDE SUMMITS. FOG COVERAGE
IN THE EAST AND SOUTH SHOULD BE REDUCED IN COVERAGE
OVERNIGHT...WITH EASTERN CHAVES AND SOUTHERN ROOSEVELT COUNTY MOST
LIKELY FOR SOME REDUCED VISIBILITIES. WITH REDUCED COVERAGE...HAVE
HELD OFF ON A FIRST STRIKE DENSE FOG ADVISORY...AND WILL SEE HOW
THINGS GO THIS EVENING.
FOR SATURDAY...KNOCK A FEW DEGREES OFF THE DAYTIME HIGHS AND MOVE
THE TROUGH AXIS INTO WESTERN NEW MEXICO...AND RAIN AND HIGH
COUNTRY SNOW COVERAGE WILL EXPAND ACROSS THE NORTH...BLANKET THE
WEST...AND REACH ACROSS THE RIO GRANDE TO THE CENTRAL MOUNTAINS BY
SATURDAY AFTERNOON. DESPITE THE HARBINGER OF WINTRY
WEATHER...DAYTIME HIGH TEMPERATURES WILL RUN IN DOUBLE DIGITS
ABOVE NORMAL IN THE EAST...WHILE REMAINING 3 TO 8 DEGREES ABOVE
NORMAL IN THE WEST. PATTERN WILL KEEP SNOW IN THE HIGH COUNTRY FOR
MUCH OF THE DAY...WITH ACCUMULATIONS RUNNING A COUPLE OF INCHES
NORTH AND WEST...AND A DUSTING TO AN INCH OR SO SHOWING UP ON THE
MID SLOPES BY SATURDAY AFTERNOON. CURRENT WINTER STORM WATCH
CONTINUES TO LOOK GOOD...AND WILL EXPLORE ACCUMULATIONS BETWEEN
THE JEMEZ...SAN JUAN...AND TUSAS MOUNTAINS AND THE SANGRE DE
CRISTO MOUNTAINS TO SEE IF ADDITIONAL WINTER STATEMENTS ARE NEEDED
FOR THE SPOTS BETWEEN. WARMER TEMPERATURES IN PLAY MAY LIMIT
ACCUMULATIONS OVER THE SANDIA AND MANZANO MOUNTAINS FOR NOW...BUT
THESE SPOTS COULD BECOME BIGGER PLAYERS SATURDAY NIGHT. AS CLOSED
LOW MOVES ACROSS THE FOUR CORNERS IN NEGATIVE TILT...AND SOLID
DYNAMICS SHOW UP IN THE IMMEDIATE BASE OF THE TROUGH...SNOW
COVERAGE HEART WILL SHIFT ACROSS CENTRAL NEW MEXICO HEADING INTO
SUNDAY MORNING...AND COLDER AIR WILL HELP SNOW COVERAGE DEVELOP
ACROSS SOUTHERN PORTIONS OF THE FORECAST AREA...WITH MOST SPOTS
EAST OF THE CENTRAL MOUNTAINS REMAINING IN THE RAIN OVERNIGHT.
WINDS WILL BE BREEZY IN SPOTS SATURDAY DAYTIME OVER THE EAST...AND
OVER THE SOUTH...BUT ANY BLOWING SNOW ISSUES SHOULD BE LOCALIZED
THROUGH MUCH OF SATURDAY NIGHT INTO SUNDAY MORNING.
FOR SUNDAY...BOMBING CLOSED LOW SHIFTING TO NORTHEAST NEW MEXICO
AND POISED TO CROSS INTO WESTERN KANSAS...AS SURFACE LOW DEEPENS
RAPIDLY OVER THE EASTERN PORTIONS OF THE OKLAHOMA PANHANDLE. MUCH
COLDER TEMPERATURES WILL BRING MOST SPOTS 3 TO 8 DEGREES BELOW MID
DECEMBER NORMALS...WITH TEMPERATURES CLOSER TO NORMAL OVER THE
EXTREME EAST. STORM FOCUS WILL SHIFT OUT OF THE WEST AND CENTRAL
AND INTO THE NORTH AND NORTHEAST SUNDAY DAYTIME WITH CONTINUED
SIGNIFICANT ACCUMULATION OVER THE SANGRE DE CRISTO RANGE...WITH
COVERAGE EXPANDING EASTWARD ALONG RATON RIDGE AND ACROSS JOHNSON
MESA ALONG THE COLORADO LINE NEAR INTERSTATE 25. SNOWFALL WILL
START TAPERING OFF ELSEWHERE. AS WINDS SHIFT TO THE NORTHWEST IN
THE WAKE OF THE DEPARTING SYSTEM...CONDITIONS WILL BECOME BREEZY
ACROSS THE CONTINENTAL DIVIDE...AND ACROSS THE CENTRAL MOUNTAINS
AND ADJACENT EASTERN PLAINS THROUGH SUNDAY AFTERNOON. LAST OF THE
SNOW WILL TAPER OFF SUNDAY NIGHT OVER THE SANGRE DE CRISTOS AND
RATON RIDGE AS WIND SPEEDS DROP OFF AFTER MIDNIGHT.
FOR MONDAY...DEPARTING STORM WILL ALLOW RIDGE FROM CHIHUAHUA
ACROSS ARIZONA TO THE GREAT SALT LAKE TO START BUILDING TOWARD NEW
MEXICO. WARMING WILL PUSH TEMPERATURES BACK UP TO WITHIN A FEW
DEGREES EITHER SIDE OF NORMAL...AS SURFACE WINDS CALM DOWN IN A
VERY WEAK SURFACE PRESSURE GRADIENT UNDER THE RIDGE. FIRST SIGNS
OF TRAILING COLD FRONT WILL TAG THE EASTERN TIER OF THE STATE LATE
MONDAY AFTERNOON...LIMITING RECOVERY FROM COOLER WEEKEND
TEMPERATURES.
OUTLOOK...TUESDAY THROUGH THURSDAY...RIDGE SHEARING EASTWARD
ACROSS THE STATE EARLY ON TUESDAY WILL MAKE ROOM FOR NEXT PACIFIC
SYSTEM WHICH WILL WORK INTO WESTERN NEW MEXICO TUESDAY NIGHT.
TUESDAY NIGHT WESTERN AND NORTHWESTERN SNOW WILL OVERSPREAD MUCH
OF THE WEST AND CENTRAL AS MOSTLY RAIN WITH HIGH COUNTRY SNOW ON
WEDNESDAY...AND CONTINUING IN A NIGHTTIME SNOW...DAYTIME RAIN
PATTERN THROUGH THURSDAY NIGHT AS THE NEXT SYSTEM IN LINE WORKS
INTO WESTERN NEW MEXICO ON THURSDAY FOR ITS TRIP EAST. GRADUAL
COOLING TREND WILL BRING MIDWEEK TEMPERATURES DOWN TO A FEW
DEGREES BELOW MID DECEMBER NORMALS...BUT THIS PACIFIC SYSTEM WILL
NOT CARRY THE COLD AIR MUCH AS ITS PREDECESSOR IN THE PREVIOUS
STORM. SYSTEM WILL ALSO HAVE MUCH LESS SURFACE INTENSITY...AS
SURFACE LOW DEEPENING OVER THE OKLAHOMA PANHANDLE WEDNESDAY WILL
EJECT EASTWARD WEDNESDAY NIGHT...RELAXING FORCING FOR
SURFACE WINDS ACROSS THE MIDPOINT OF THE WORK WEEK.
SHY
&&
.FIRE WEATHER...
UNSETTLED WEATHER WITH RAIN/SNOW EXPECTED FOR THIS
WEEKEND...PRIMARILY SATURDAY NIGHT INTO SUNDAY. ANOTHER WETTING
SYSTEM POSSIBLE MIDWEEK.
AS THE RIDGE AXIS SHIFTS EAST...HIGH CLOUDS WILL INCREASE ALONG WITH
SOUTHWEST FLOW OVERNIGHT INTO SATURDAY ACROSS THE EAST CENTRAL
PLAINS. OVERNIGHT RH RECOVERIES WILL BE EXCELLENT ACROSS WESTERN AND
CENTRAL AREAS...GOOD TO FAIR EAST OF THE CENTRAL MOUNTAIN CHAIN.
TEMPERATURES WILL START COOLING SATURDAY AS THE PACIFIC LOW
APPROACHES THE STATE FROM THE WEST. THE WEST WILL SEE WETTING
PRECIPITATION IN THE FORM OF LOW ELEVATION RAIN...HIGH ELEVATION/MOUNTAIN
SNOW. WINDS WILL BE BREEZY TO GUSTY OUT OF THE SOUTH TO
SOUTHWEST...WITH GUSTIER WINDS ACROSS THE EAST CENTRAL PLAINS.
VENTILATION RATES WILL IMPROVE ACROSS WESTERN AND CENTRAL AREA.
DESPITE THE GUSTIER WINDS...HUMIDITY READINGS WILL REMAIN ABOVE
CRITICAL LEVELS.
SATURDAY NIGHT INTO SUNDAY MORNING...NORTHERN AND CENTRAL AREAS WILL
SEE RAIN/SNOW SHOWERS AS THE COLD FRONT PUSHES EAST. SNOW
ACCUMULATIONS WILL BE GREATER ALONG THE HIGHER ELEVATIONS. SNOW
LEVELS WILL BE MUCH LOWER WITH THIS SYSTEM THE PAST FEW.
TEMPERATURES WILL FALL BELOW NORMAL WITH COOLER AIR COMING IN ON
SUNDAY. EXPECT CONTINUED GOOD TO EXCELLENT VENTILATION RATES MOST
AREAS ON SUNDAY. WINDS WILL CONTINUE TO BE STRONG ACROSS THE EAST
CENTRAL PLAINS. DURING SUNDAY NIGHT...THE STORM WILL EXIT TO THE
NORTHEAST WITH WRAP WETTING PRECIPITATION AND COOLER AIR ACROSS NORTH
CENTRAL AND NORTHEAST AREAS.
TEMPERATURES IN THE WEST WILL REBOUND TO NEAR NORMAL WITH POOR
VENTILATION AREA WIDE AS AN UPPER LEVEL RIDGE BUILDS OVER THE
REGION. AFTER MONDAY...WE BEGIN TO SEE ROLLER COASTER VENTILATION
RATES AS MODELS BEGIN TO PICK UP ANOTHER APPROACHING PACIFIC STORM
SYSTEM BY MIDWEEK AND ANOTHER FOR THE FOLLOWING WEEKEND. ECMWF IS
MORE BULLISH ON WETTER CONDITIONS THAN THE GFS DURING THE MIDWEEK
PERIOD. CONFIDENCE IS PRETTY HIGH FOR ANOTHER WETTING EVENT MIDWEEK
AND MODERATE FOR THE FOLLOWING WEEKEND.
CML
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY AFTERNOON
FOR THE FOLLOWING ZONES...NMZ510>515-521.
&&
$$
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
114 PM EST FRI DEC 12 2014
.SYNOPSIS...
NEARLY STATIONARY LOW PRESSURE WILL REMAIN ATOP THE REGION
THROUGH SATURDAY BEFORE SLOWLY PULLING EAST AND LOSING INFLUENCE
ON DAILY WEATHER CONDITIONS BY SATURDAY NIGHT INTO SUNDAY.
SCATTERED TO NUMEROUS SNOW SHOWERS WILL REMAIN PREVALENT ACROSS
THE NORTH TODAY INTO TONIGHT BEFORE SENSIBLE WEATHER TRENDS DRIER
THROUGH THE DAY ON SATURDAY. TEMPERATURES WILL REMAIN VERY SIMILAR
TO READINGS OVER THE PAST FEW DAYS...HOLDING SLIGHTLY ABOVE EARLY
WINTER NORMS.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AS OF 1219 PM EST FRIDAY...NO SIGNIFICANT CHANGES FOR 1230 UPDATE.
PREVIOUS DISCUSSIONS FOLLOW. HAVE INCREASED POPS FOR THIS MORNING
IN THE CHAMPLAIN VALLEY AND SAINT LAWRENCE VALLEY FOR CURRENT
RADAR TRENDS. STILL THINK CHANCE FOR SNOW SHOWERS WILL INCREASE
THIS AFTERNOON WITH SHORTWAVE MOVING THROUGH THE AREA. A DUSTING
TO TWO INCHES LOOKS GOOD.
PRIOR DISCUSSION FROM 330 AM EST FRIDAY... BROKEN RECORD FORECAST
CONTINUES TODAY INTO TONIGHT WITH STATIONARY OCCLUSION REMAINING
ATOP OR JUST EAST OF THE FORECAST AREA. MOIST CYCLONIC FLOW
COMBINED WITH WEAK SHORTWAVE ENERGY BUNDLES DROPPING SOUTHWARD
WILL COMBINE TO KEEP SCATTERED TO NUMEROUS SNOW SHOWERS OR PERIODS
OF LIGHT SNOW ONGOING ACROSS MUCH OF OUR CENTRAL AND NORTHERN
COUNTIES...ESPECIALLY FROM THE ADIRONDACKS EASTWARD. SOME MINOR
ADDITIONAL ACCUMULATIONS LIKELY...SIMILAR TO YESTERDAY AND
ESPECIALLY ACROSS THE HIGHER TERRAIN WHERE SFC TEMPERATURES WILL
BE A FEW DEGREES COOLER. LESS OVERALL COVERAGE ACROSS THE SOUTHERN
VALLEYS. ALSO INTRODUCED THE CHANCE FOR SOME INTERMITTENT -FZDZ
ACROSS OUR FAR WESTERN COUNTIES WHERE RAP SOUNDING PROFILES
SUGGEST AN UNSATURATED SNOW GROWTH ZONE THROUGH LATE MORNING/EARLY
AFTERNOON. SIMILAR TO THE UPPER PATTERN...TEMPERATURES ALSO GOING
NOWHERE AND NEARLY IDENTICAL TO READINGS OVER THE PAST FEW DAYS
HOLDING IN THE UPPER 20S TO MID 30S DURING THE DAY AND SETTLING
BACK INTO THE 20S OVERNIGHT.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH SUNDAY/...
AS OF 330 AM EST FRIDAY...BY SATURDAY MODEL SUITE SHOWING GOOD
CONSENSUS THAT OUR PESKY UPPER LOW WILL SLOWLY BEGIN TO PULL
EASTWARD SUCH THAT DEEPER MOISTURE AND OVERALL INFLUENCE WILL WANE
OVER TIME. STILL COULD SEE SOME LINGERING NRN MTN FLURRY/SHSN
ACTIVITY HERE AND THERE...BUT AREAL COVERAGE WILL BY AND LARGE BE
LESS THAN TODAY WITH BROADER VALLEYS MAINLY DRY. LIGHT WINDS AND
LACK OF THERMAL ADVECTIVE PROCESSES MEAN NO AIRMASS CHANGE SO HIGH
TEMPERATURES...YOU GUESSED IT...NEARLY IDENTICAL TO TODAY IN THE
UPPER 20S TO MID 30S.
BY SATURDAY NIGHT UPPER LEVEL RIDGING TO OUR WEST FINALLY BEGINS
TO MAKE INROADS EAST AS UPPER LOW CONTINUES TO PULL SLOWLY AWAY
OFFSHORE. A SOMEWHAT TRICKY CLOUD FORECAST WITH VARYING SOLUTIONS
OFFERED ON DEGREE OF COOLING. POTENTIAL BUST WITH MINIMUM
TEMPERATURES GIVEN POSSIBLE CLEARING AND FRESH SNOW COVER...SO
WILL LEAN CONSERVATIVELY TOWARD A BLEND OF AVBL GUIDANCE SHOWING
VARIABLE CLOUDS THINNING ONLY SLOWLY AND LOW TEMPS ABOUT 5 DEGREES
COLDER THAN TONIGHT...UPPER TEENS TO MID 20S OR SO.
ON SUNDAY DEEP LEVEL RIDGING MAKES FURTHER PROGRESS INTO THE
REGION WITH CONTINUED DRYING THROUGH THE PBL AND INCREASING
AMOUNTS OF SUN AS UPPER FLOW TRENDS ANTICYCLONIC/SUBSIDENT. 850 MB
RESPOND AND RANGE FROM 0C TO +5C EAST TO WEST ACROSS THE AREA BY
AFTERNOON. HOWEVER A LIGHT NORTHERLY FLOW ALONG WITH A SHALLOW
MIXED LAYER TO ONLY 1500 FEET OR SO WILL KEEP TEMPERATURES COOLER
THAN WHAT THOSE READINGS WOULD NORMALLY INDICATE WITH MOST SPOTS
TOPPING OUT ONLY IN THE 30S. STILL QUITE A NICE DAY THOUGH WITH
THE SUNSHINE BEING WELCOME AFTER NEARLY A WEEK OF HIDING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 330 AM EST FRIDAY...A BUILDING UPPER LEVEL RIDGE WILL BRING
DRY WEATHER TO THE AREA EARLY NEXT WEEK. THAT HIGH PRESSURE WILL
BE SHORT LIVED AS WEAKLY NEGATIVELY TILTED TROUGH WILL PUSH INTO
THE AREA. THERE IS INCREASING CONSENSUS THAT SNOWS SHOWERS WILL
RETURN ON WEDNESDAY AS THE WEAK COLD FRONT CROSSES THE REGION.
DURING THE DAY ON WEDNESDAY THE MODELS DIVULGE WITH THE GFS
BRINGING A WEAKER UPPER LEVEL LOW AND THE ECMWF BRINGING A MORE
ROBUST SYSTEM THROUGH. THE ECMWF KEEPS SHOWERS IN THE REGION
THROUGH THURSDAY WHEREAS THE GFS IS QUICKER TO DRY OUT. A WEAK
RIDGE WILL BRING DRIER WEATHER BACK INTO THE AREA WITH SEASONAL
TEMPS THROUGHOUT THE EXTENDED. MODEL GUIDANCE CONTINUES TO SHOW
LITTLE TO NO ARCTIC AIR MOVING IN WITH FRONT SO AT THIS POINT WE
DONT EXPECT ANY SURGES OF COLD AIR INTO THE REGION THROUGH THE
LATE WEEK NEXT WEEK.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...LOW PRESSURE RESPONSIBLE FOR LOW CEILINGS
AND REDUCED VISIBILITIES IN LIGHT SNOW WILL DRIFT SLOWLY EASTWARD
ACROSS NEW ENGLAND THROUGH THE PERIOD. CONDITIONS WILL VARY FROM
MVFR TO IFR ACROSS THE FORECAST AREA THIS AFTERNOON THROUGH
TONIGHT WITH PERIODS OF LIGHT SNOW CONTINUING. RISK OF IFR WILL BE
HIGHEST THROUGH ABOUT MIDNIGHT TONIGHT. CHANCES FOR SNOW SHOWERS
WILL BE DECREASING DURING SATURDAY WITH CONDITIONS TRENDING MVFR
TO VFR AT MSS/PBG/RUT DURING THE MORNING...BUT NOT UNTIL LATER IN
THE DAY AT REST OF SITES. WINDS WILL BE WEST TO NORTHWEST AT 5 TO
10 KNOTS THROUGH THE PERIOD.
OUTLOOK 18Z SATURDAY THROUGH WEDNESDAY...
18Z SAT - 06Z SUN...LINGERING MVFR TRENDING TO VFR AS HIGH
PRESSURE BUILDS INTO THE REGION.
06Z SUN - 00Z WED...VFR CONDITIONS WITH DRIER WEATHER EXPECTED.
00Z WED - 00Z THU...MVFR WITH PERIODS OF IFR EXPECTED DUE TO
SNOW/RAIN SHOWERS ASSOCIATED WITH APPROACHING LOW PRESSURE SYSTEM.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG/NEILES
SHORT TERM...JMG
LONG TERM...DEAL
AVIATION...RJS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1220 PM EST FRI DEC 12 2014
.SYNOPSIS...
NEARLY STATIONARY LOW PRESSURE WILL REMAIN ATOP THE REGION
THROUGH SATURDAY BEFORE SLOWLY PULLING EAST AND LOSING INFLUENCE
ON DAILY WEATHER CONDITIONS BY SATURDAY NIGHT INTO SUNDAY.
SCATTERED TO NUMEROUS SNOW SHOWERS WILL REMAIN PREVALENT ACROSS
THE NORTH TODAY INTO TONIGHT BEFORE SENSIBLE WEATHER TRENDS DRIER
THROUGH THE DAY ON SATURDAY. TEMPERATURES WILL REMAIN VERY SIMILAR
TO READINGS OVER THE PAST FEW DAYS...HOLDING SLIGHTLY ABOVE EARLY
WINTER NORMS.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AS OF 1219 PM EST FRIDAY...NO SIGNIFICANT CHANGES FOR 1230 UPDATE.
PREVIOUS DISCUSSIONS FOLLOW. HAVE INCREASED POPS FOR THIS MORNING
IN THE CHAMPLAIN VALLEY AND SAINT LAWRENCE VALLEY FOR CURRENT
RADAR TRENDS. STILL THINK CHANCE FOR SNOW SHOWERS WILL INCREASE
THIS AFTERNOON WITH SHORTWAVE MOVING THROUGH THE AREA. A DUSTING
TO TWO INCHES LOOKS GOOD.
PRIOR DISCUSSION FROM 330 AM EST FRIDAY... BROKEN RECORD FORECAST
CONTINUES TODAY INTO TONIGHT WITH STATIONARY OCCLUSION REMAINING
ATOP OR JUST EAST OF THE FORECAST AREA. MOIST CYCLONIC FLOW
COMBINED WITH WEAK SHORTWAVE ENERGY BUNDLES DROPPING SOUTHWARD
WILL COMBINE TO KEEP SCATTERED TO NUMEROUS SNOW SHOWERS OR PERIODS
OF LIGHT SNOW ONGOING ACROSS MUCH OF OUR CENTRAL AND NORTHERN
COUNTIES...ESPECIALLY FROM THE ADIRONDACKS EASTWARD. SOME MINOR
ADDITIONAL ACCUMULATIONS LIKELY...SIMILAR TO YESTERDAY AND
ESPECIALLY ACROSS THE HIGHER TERRAIN WHERE SFC TEMPERATURES WILL
BE A FEW DEGREES COOLER. LESS OVERALL COVERAGE ACROSS THE SOUTHERN
VALLEYS. ALSO INTRODUCED THE CHANCE FOR SOME INTERMITTENT -FZDZ
ACROSS OUR FAR WESTERN COUNTIES WHERE RAP SOUNDING PROFILES
SUGGEST AN UNSATURATED SNOW GROWTH ZONE THROUGH LATE MORNING/EARLY
AFTERNOON. SIMILAR TO THE UPPER PATTERN...TEMPERATURES ALSO GOING
NOWHERE AND NEARLY IDENTICAL TO READINGS OVER THE PAST FEW DAYS
HOLDING IN THE UPPER 20S TO MID 30S DURING THE DAY AND SETTLING
BACK INTO THE 20S OVERNIGHT.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH SUNDAY/...
AS OF 330 AM EST FRIDAY...BY SATURDAY MODEL SUITE SHOWING GOOD
CONSENSUS THAT OUR PESKY UPPER LOW WILL SLOWLY BEGIN TO PULL
EASTWARD SUCH THAT DEEPER MOISTURE AND OVERALL INFLUENCE WILL WANE
OVER TIME. STILL COULD SEE SOME LINGERING NRN MTN FLURRY/SHSN
ACTIVITY HERE AND THERE...BUT AREAL COVERAGE WILL BY AND LARGE BE
LESS THAN TODAY WITH BROADER VALLEYS MAINLY DRY. LIGHT WINDS AND
LACK OF THERMAL ADVECTIVE PROCESSES MEAN NO AIRMASS CHANGE SO HIGH
TEMPERATURES...YOU GUESSED IT...NEARLY IDENTICAL TO TODAY IN THE
UPPER 20S TO MID 30S.
BY SATURDAY NIGHT UPPER LEVEL RIDGING TO OUR WEST FINALLY BEGINS
TO MAKE INROADS EAST AS UPPER LOW CONTINUES TO PULL SLOWLY AWAY
OFFSHORE. A SOMEWHAT TRICKY CLOUD FORECAST WITH VARYING SOLUTIONS
OFFERED ON DEGREE OF COOLING. POTENTIAL BUST WITH MINIMUM
TEMPERATURES GIVEN POSSIBLE CLEARING AND FRESH SNOW COVER...SO
WILL LEAN CONSERVATIVELY TOWARD A BLEND OF AVBL GUIDANCE SHOWING
VARIABLE CLOUDS THINNING ONLY SLOWLY AND LOW TEMPS ABOUT 5 DEGREES
COLDER THAN TONIGHT...UPPER TEENS TO MID 20S OR SO.
ON SUNDAY DEEP LEVEL RIDGING MAKES FURTHER PROGRESS INTO THE
REGION WITH CONTINUED DRYING THROUGH THE PBL AND INCREASING
AMOUNTS OF SUN AS UPPER FLOW TRENDS ANTICYCLONIC/SUBSIDENT. 850 MB
RESPOND AND RANGE FROM 0C TO +5C EAST TO WEST ACROSS THE AREA BY
AFTERNOON. HOWEVER A LIGHT NORTHERLY FLOW ALONG WITH A SHALLOW
MIXED LAYER TO ONLY 1500 FEET OR SO WILL KEEP TEMPERATURES COOLER
THAN WHAT THOSE READINGS WOULD NORMALLY INDICATE WITH MOST SPOTS
TOPPING OUT ONLY IN THE 30S. STILL QUITE A NICE DAY THOUGH WITH
THE SUNSHINE BEING WELCOME AFTER NEARLY A WEEK OF HIDING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 330 AM EST FRIDAY...A BUILDING UPPER LEVEL RIDGE WILL BRING
DRY WEATHER TO THE AREA EARLY NEXT WEEK. THAT HIGH PRESSURE WILL
BE SHORT LIVED AS WEAKLY NEGATIVELY TILTED TROUGH WILL PUSH INTO
THE AREA. THERE IS INCREASING CONSENSUS THAT SNOWS SHOWERS WILL
RETURN ON WEDNESDAY AS THE WEAK COLD FRONT CROSSES THE REGION.
DURING THE DAY ON WEDNESDAY THE MODELS DIVULGE WITH THE GFS
BRINGING A WEAKER UPPER LEVEL LOW AND THE ECMWF BRINGING A MORE
ROBUST SYSTEM THROUGH. THE ECMWF KEEPS SHOWERS IN THE REGION
THROUGH THURSDAY WHEREAS THE GFS IS QUICKER TO DRY OUT. A WEAK
RIDGE WILL BRING DRIER WEATHER BACK INTO THE AREA WITH SEASONAL
TEMPS THROUGHOUT THE EXTENDED. MODEL GUIDANCE CONTINUES TO SHOW
LITTLE TO NO ARCTIC AIR MOVING IN WITH FRONT SO AT THIS POINT WE
DONT EXPECT ANY SURGES OF COLD AIR INTO THE REGION THROUGH THE
LATE WEEK NEXT WEEK.
&&
.AVIATION /17Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 12Z SATURDAY...CONDITIONS WILL VARY FROM SITE TO SITE
THROUGH THE PERIOD. EXPECT MVFR CONDITIONS PREVAILING WITH BOUTS
OF IFR SNOW SHOWERS IN THE CHAMPLAIN VALLEY AND AT KMPV. MVFR
CONDITIONS LIFTING TO VFR IN THE AFTERNOON TOMORROW AT KRUT. IFR
CEILINGS WILL PERSIST THROUGH THE EARLY MORNING AT KMSS AND MVFR
CONDITIONS WITH PERIODS OF IFR CEILING WILL OCCUR AT KSLK. AS THE
SURFACE LOW CONTINUES TO JUST SLOWLY MEANDER AROUND THERE WILL BE
SOME SCATTED LIGHT SNOW SHOWER MAINLY IN THE CHAMPLAIN VALLEY
OVERNIGHT. AFTER 18Z THERE WILL BE AN ENHANCED SURGE OF SNOW
SHOWERS DURING THE AFTERNOON AT THE NORTHERN VT SITES. FOR KMSS A
PERIOD OF LIGHT SHOWERS BROUGHT IN A PERIOD OF IFR VISIBILITIES
AND CONDITIONS ARE STARTING TO IMPROVE. EXPECT MVFR CEILINGS WITH
PERIODS OF IFR VIS ARE FZDZ AND SNOW FAIL THROUGH THE MORNING.
WINDS WILL CONTINUE TO REMAIN LIGHT NORTHERLY THROUGHOUT THE
PERIOD.
OUTLOOK 12Z SATURDAY THROUGH WEDNESDAY...
12Z FRIDAY - 12Z SATURDAY...LOW PRESSURE BEGINS TO PULL NORTHEAST
OF THE REGION WITH PRECIPITATION BECOMING MORE SCATTERED...BUT
MVFR/IFR CONDITIONS LIKELY TO REMAIN IN LIGHT SNOW ESPECIALLY
ACROSS THE HIGHER TERRAIN.
12Z SATURDAY - 06Z SUNDAY...LINGERING MVFR TRENDING TO VFR AS
HIGH PRESSURE BUILDS ACROSS THE REGION.
06Z SUNDAY - 00Z WEDNESDAY...VFR CONDITIONS WITH DRIER WEATHER
EXPECTED.
00Z WEDNESDAY...MVFR WITH PERIOD OF IFR EXPECTED DUE TO SNOW
SHOWERS ASSOCIATED WITH AN ADVANCING LOW PRESSURE SYSTEM.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG/NEILES
SHORT TERM...JMG
LONG TERM...DEAL
AVIATION...DEAL
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
941 AM EST FRI DEC 12 2014
.SYNOPSIS...
NEARLY STATIONARY LOW PRESSURE WILL REMAIN ATOP THE REGION
THROUGH SATURDAY BEFORE SLOWLY PULLING EAST AND LOSING INFLUENCE
ON DAILY WEATHER CONDITIONS BY SATURDAY NIGHT INTO SUNDAY.
SCATTERED TO NUMEROUS SNOW SHOWERS WILL REMAIN PREVALENT ACROSS
THE NORTH TODAY INTO TONIGHT BEFORE SENSIBLE WEATHER TRENDS DRIER
THROUGH THE DAY ON SATURDAY. TEMPERATURES WILL REMAIN VERY SIMILAR
TO READINGS OVER THE PAST FEW DAYS...HOLDING SLIGHTLY ABOVE EARLY
WINTER NORMS.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
AS OF 937 AM EST FRIDAY...HAVE INCREASED POPS FOR THIS MORNING IN
THE CHAMPLAIN VALLEY AND SAINT LAWRENCE VALLEY FOR CURRENT RADAR
TRENDS. STILL THINK CHANCE FOR SNOW SHOWERS WILL INCREASE THIS
AFTERNOON WITH SHORTWAVE MOVING THROUGH THE AREA. A DUSTING TO TWO
INCHES LOOKS GOOD.
PRIOR DISCUSSION FROM 330 AM EST FRIDAY... BROKEN RECORD FORECAST
CONTINUES TODAY INTO TONIGHT WITH STATIONARY OCCLUSION REMAINING
ATOP OR JUST EAST OF THE FORECAST AREA. MOIST CYCLONIC FLOW
COMBINED WITH WEAK SHORTWAVE ENERGY BUNDLES DROPPING SOUTHWARD
WILL COMBINE TO KEEP SCATTERED TO NUMEROUS SNOW SHOWERS OR PERIODS
OF LIGHT SNOW ONGOING ACROSS MUCH OF OUR CENTRAL AND NORTHERN
COUNTIES...ESPECIALLY FROM THE ADIRONDACKS EASTWARD. SOME MINOR
ADDITIONAL ACCUMULATIONS LIKELY...SIMILAR TO YESTERDAY AND
ESPECIALLY ACROSS THE HIGHER TERRAIN WHERE SFC TEMPERATURES WILL
BE A FEW DEGREES COOLER. LESS OVERALL COVERAGE ACROSS THE SOUTHERN
VALLEYS. ALSO INTRODUCED THE CHANCE FOR SOME INTERMITTENT -FZDZ
ACROSS OUR FAR WESTERN COUNTIES WHERE RAP SOUNDING PROFILES
SUGGEST AN UNSATURATED SNOW GROWTH ZONE THROUGH LATE MORNING/EARLY
AFTERNOON. SIMILAR TO THE UPPER PATTERN...TEMPERATURES ALSO GOING
NOWHERE AND NEARLY IDENTICAL TO READINGS OVER THE PAST FEW DAYS
HOLDING IN THE UPPER 20S TO MID 30S DURING THE DAY AND SETTLING
BACK INTO THE 20S OVERNIGHT.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH SUNDAY/...
AS OF 330 AM EST FRIDAY...BY SATURDAY MODEL SUITE SHOWING GOOD
CONSENSUS THAT OUR PESKY UPPER LOW WILL SLOWLY BEGIN TO PULL
EASTWARD SUCH THAT DEEPER MOISTURE AND OVERALL INFLUENCE WILL WANE
OVER TIME. STILL COULD SEE SOME LINGERING NRN MTN FLURRY/SHSN
ACTIVITY HERE AND THERE...BUT AREAL COVERAGE WILL BY AND LARGE BE
LESS THAN TODAY WITH BROADER VALLEYS MAINLY DRY. LIGHT WINDS AND
LACK OF THERMAL ADVECTIVE PROCESSES MEAN NO AIRMASS CHANGE SO HIGH
TEMPERATURES...YOU GUESSED IT...NEARLY IDENTICAL TO TODAY IN THE
UPPER 20S TO MID 30S.
BY SATURDAY NIGHT UPPER LEVEL RIDGING TO OUR WEST FINALLY BEGINS
TO MAKE INROADS EAST AS UPPER LOW CONTINUES TO PULL SLOWLY AWAY
OFFSHORE. A SOMEWHAT TRICKY CLOUD FORECAST WITH VARYING SOLUTIONS
OFFERED ON DEGREE OF COOLING. POTENTIAL BUST WITH MINIMUM
TEMPERATURES GIVEN POSSIBLE CLEARING AND FRESH SNOW COVER...SO
WILL LEAN CONSERVATIVELY TOWARD A BLEND OF AVBL GUIDANCE SHOWING
VARIABLE CLOUDS THINNING ONLY SLOWLY AND LOW TEMPS ABOUT 5 DEGREES
COLDER THAN TONIGHT...UPPER TEENS TO MID 20S OR SO.
ON SUNDAY DEEP LEVEL RIDGING MAKES FURTHER PROGRESS INTO THE
REGION WITH CONTINUED DRYING THROUGH THE PBL AND INCREASING
AMOUNTS OF SUN AS UPPER FLOW TRENDS ANTICYCLONIC/SUBSIDENT. 850 MB
RESPOND AND RANGE FROM 0C TO +5C EAST TO WEST ACROSS THE AREA BY
AFTERNOON. HOWEVER A LIGHT NORTHERLY FLOW ALONG WITH A SHALLOW
MIXED LAYER TO ONLY 1500 FEET OR SO WILL KEEP TEMPERATURES COOLER
THAN WHAT THOSE READINGS WOULD NORMALLY INDICATE WITH MOST SPOTS
TOPPING OUT ONLY IN THE 30S. STILL QUITE A NICE DAY THOUGH WITH
THE SUNSHINE BEING WELCOME AFTER NEARLY A WEEK OF HIDING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 330 AM EST FRIDAY...A BUILDING UPPER LEVEL RIDGE WILL BRING
DRY WEATHER TO THE AREA EARLY NEXT WEEK. THAT HIGH PRESSURE WILL
BE SHORT LIVED AS WEAKLY NEGATIVELY TILTED TROUGH WILL PUSH INTO
THE AREA. THERE IS INCREASING CONSENSUS THAT SNOWS SHOWERS WILL
RETURN ON WEDNESDAY AS THE WEAK COLD FRONT CROSSES THE REGION.
DURING THE DAY ON WEDNESDAY THE MODELS DIVULGE WITH THE GFS
BRINGING A WEAKER UPPER LEVEL LOW AND THE ECMWF BRINGING A MORE
ROBUST SYSTEM THROUGH. THE ECMWF KEEPS SHOWERS IN THE REGION
THROUGH THURSDAY WHEREAS THE GFS IS QUICKER TO DRY OUT. A WEAK
RIDGE WILL BRING DRIER WEATHER BACK INTO THE AREA WITH SEASONAL
TEMPS THROUGHOUT THE EXTENDED. MODEL GUIDANCE CONTINUES TO SHOW
LITTLE TO NO ARCTIC AIR MOVING IN WITH FRONT SO AT THIS POINT WE
DONT EXPECT ANY SURGES OF COLD AIR INTO THE REGION THROUGH THE
LATE WEEK NEXT WEEK.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
THROUGH 12Z SATURDAY...CONDITIONS WILL VARY FROM SITE TO SITE
THROUGH THE PERIOD. EXPECT MVFR CONDITIONS PREVAILING WITH BOUTS
OF IFR SNOW SHOWERS IN THE CHAMPLAIN VALLEY AND AT KMPV. MVFR
CONDITIONS LIFTING TO VFR IN THE AFTERNOON TOMORROW AT KRUT. IFR
CEILINGS WILL PERSIST THROUGH THE EARLY MORNING AT KMSS AND MVFR
CONDITIONS WITH PERIODS OF IFR CEILING WILL OCCUR AT KSLK. AS THE
SURFACE LOW CONTINUES TO JUST SLOWLY MEANDER AROUND THERE WILL BE
SOME SCATTED LIGHT SNOW SHOWER MAINLY IN THE CHAMPLAIN VALLEY
OVERNIGHT. AFTER 18Z THERE WILL BE AN ENHANCED SURGE OF SNOW
SHOWERS DURING THE AFTERNOON AT THE NORTHERN VT SITES. FOR KMSS A
PERIOD OF LIGHT SHOWERS BROUGHT IN A PERIOD OF IFR VISIBILITIES
AND CONDITIONS ARE STARTING TO IMPROVE. EXPECT MVFR CEILINGS WITH
PERIODS OF IFR VIS ARE FZDZ AND SNOW FAIL THROUGH THE MORNING.
WINDS WILL CONTINUE TO REMAIN LIGHT NORTHERLY THROUGHOUT THE
PERIOD.
OUTLOOK 12Z SATURDAY THROUGH WEDNESDAY...
12Z FRIDAY - 12Z SATURDAY...LOW PRESSURE BEGINS TO PULL NORTHEAST
OF THE REGION WITH PRECIPITATION BECOMING MORE SCATTERED...BUT
MVFR/IFR CONDITIONS LIKELY TO REMAIN IN LIGHT SNOW ESPECIALLY
ACROSS THE HIGHER TERRAIN.
12Z SATURDAY - 06Z SUNDAY...LINGERING MVFR TRENDING TO VFR AS
HIGH PRESSURE BUILDS ACROSS THE REGION.
06Z SUNDAY - 00Z WEDNESDAY...VFR CONDITIONS WITH DRIER WEATHER
EXPECTED.
00Z WEDNESDAY...MVFR WITH PERIOD OF IFR EXPECTED DUE TO SNOW
SHOWERS ASSOCIATED WITH AN ADVANCING LOW PRESSURE SYSTEM.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG/NEILES
SHORT TERM...JMG
LONG TERM...DEAL
AVIATION...DEAL
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
713 AM EST FRI DEC 12 2014
.SYNOPSIS...
NEARLY STATIONARY LOW PRESSURE WILL REMAIN ATOP THE REGION THROUGH
SATURDAY BEFORE SLOWLY PULLING EAST AND LOSING INFLUENCE ON DAILY
WEATHER CONDITIONS BY SATURDAY NIGHT INTO SUNDAY. SCATTERED TO
NUMEROUS SNOW SHOWERS WILL REMAIN PREVALENT ACROSS THE NORTH TODAY
INTO TONIGHT BEFORE SENSIBLE WEATHER TRENDS DRIER THROUGH THE DAY ON
SATURDAY. TEMPERATURES WILL REMAIN VERY SIMILAR TO READINGS OVER THE
PAST FEW DAYS...HOLDING SLIGHTLY ABOVE EARLY WINTER NORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 632 AM EST FRIDAY...GOING FORECAST REMAINS IN GOOD SHAPE.
ADJUSTED HOURLY T/TD DATASETS TO MATCH CURRENT OBSERVATIONAL
TRENDS, OTHERWISE LITTLE CHANGES WERE NEEDED AS OF 600 AM.
WATCHING SCATTERED AREAS OF LIGHT SNOW/SHSN/FLURRIES CONTINUING TO
SINK SOUTHWARD INTO CENTRAL AND NRN PORTIONS OF THE FORECAST AREA
AND STILL EXPECT THIS ACTIVITY TO CONTINUE ON AND OFF FOR A GOOD
PORTION OF THE DAY IN THESE AREAS WITH A GENERAL DUSTING TO 2
INCHES EXPECTED. HIGHEST AMOUNTS IN THE NRN MTNS OF VT. PRIOR
DISCUSSION FOLLOWS. HAVE A GREAT DAY.
PRIOR DISCUSSION FROM 330 AM EST FRIDAY...
BROKEN RECORD FORECAST CONTINUES TODAY INTO TONIGHT WITH
STATIONARY OCCLUSION REMAINING ATOP OR JUST EAST OF THE FORECAST
AREA. MOIST CYCLONIC FLOW COMBINED WITH WEAK SHORTWAVE ENERGY
BUNDLES DROPPING SOUTHWARD WILL COMBINE TO KEEP SCATTERED TO
NUMEROUS SNOW SHOWERS OR PERIODS OF LIGHT SNOW ONGOING ACROSS MUCH
OF OUR CENTRAL AND NORTHERN COUNTIES...ESPECIALLY FROM THE
ADIRONDACKS EASTWARD. SOME MINOR ADDITIONAL ACCUMULATIONS
LIKELY...SIMILAR TO YESTERDAY AND ESPECIALLY ACROSS THE HIGHER
TERRAIN WHERE SFC TEMPERATURES WILL BE A FEW DEGREES COOLER. LESS
OVERALL COVERAGE ACROSS THE SOUTHERN VALLEYS. ALSO INTRODUCED THE
CHANCE FOR SOME INTERMITTENT -FZDZ ACROSS OUR FAR WESTERN COUNTIES
WHERE RAP SOUNDING PROFILES SUGGEST AN UNSATURATED SNOW GROWTH
ZONE THROUGH LATE MORNING/EARLY AFTERNOON. SIMILAR TO THE UPPER
PATTERN...TEMPERATURES ALSO GOING NOWHERE AND NEARLY IDENTICAL TO
READINGS OVER THE PAST FEW DAYS HOLDING IN THE UPPER 20S TO MID
30S DURING THE DAY AND SETTLING BACK INTO THE 20S OVERNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 330 AM EST FRIDAY...BY SATURDAY MODEL SUITE SHOWING GOOD
CONSENSUS THAT OUR PESKY UPPER LOW WILL SLOWLY BEGIN TO PULL
EASTWARD SUCH THAT DEEPER MOISTURE AND OVERALL INFLUENCE WILL WANE
OVER TIME. STILL COULD SEE SOME LINGERING NRN MTN FLURRY/SHSN
ACTIVITY HERE AND THERE...BUT AREAL COVERAGE WILL BY AND LARGE BE
LESS THAN TODAY WITH BROADER VALLEYS MAINLY DRY. LIGHT WINDS AND
LACK OF THERMAL ADVECTIVE PROCESSES MEAN NO AIRMASS CHANGE SO HIGH
TEMPERATURES...YOU GUESSED IT...NEARLY IDENTICAL TO TODAY IN THE
UPPER 20S TO MID 30S.
BY SATURDAY NIGHT UPPER LEVEL RIDGING TO OUR WEST FINALLY BEGINS TO
MAKE INROADS EAST AS UPPER LOW CONTINUES TO PULL SLOWLY AWAY
OFFSHORE. A SOMEWHAT TRICKY CLOUD FORECAST WITH VARYING SOLUTIONS
OFFERED ON DEGREE OF COOLING. POTENTIAL BUST WITH MINIMUM
TEMPERATURES GIVEN POSSIBLE CLEARING AND FRESH SNOW COVER...SO WILL
LEAN CONSERVATIVELY TOWARD A BLEND OF AVBL GUIDANCE SHOWING VARIABLE
CLOUDS THINNING ONLY SLOWLY AND LOW TEMPS ABOUT 5 DEGREES COLDER
THAN TONIGHT...UPPER TEENS TO MID 20S OR SO.
ON SUNDAY DEEP LEVEL RIDGING MAKES FURTHER PROGRESS INTO THE REGION
WITH CONTINUED DRYING THROUGH THE PBL AND INCREASING AMOUNTS OF SUN
AS UPPER FLOW TRENDS ANTICYCLONIC/SUBSIDENT. 850 MB RESPOND AND
RANGE FROM 0C TO +5C EAST TO WEST ACROSS THE AREA BY AFTERNOON.
HOWEVER A LIGHT NORTHERLY FLOW ALONG WITH A SHALLOW MIXED LAYER
TO ONLY 1500 FEET OR SO WILL KEEP TEMPERATURES COOLER THAN WHAT
THOSE READINGS WOULD NORMALLY INDICATE WITH MOST SPOTS TOPPING OUT
ONLY IN THE 30S. STILL QUITE A NICE DAY THOUGH WITH THE SUNSHINE
BEING WELCOME AFTER NEARLY A WEEK OF HIDING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 330 AM EST FRIDAY...A BUILDING UPPER LEVEL RIDGE WILL BRING
DRY WEATHER TO THE AREA EARLY NEXT WEEK. THAT HIGH PRESSURE WILL
BE SHORT LIVED AS WEAKLY NEGATIVELY TILTED TROUGH WILL PUSH INTO
THE AREA. THERE IS INCREASING CONSENSUS THAT SNOWS SHOWERS WILL
RETURN ON WEDNESDAY AS THE WEAK COLD FRONT CROSSES THE REGION.
DURING THE DAY ON WEDNESDAY THE MODELS DIVULGE WITH THE GFS
BRINGING A WEAKER UPPER LEVEL LOW AND THE ECMWF BRINGING A MORE
ROBUST SYSTEM THROUGH. THE ECMWF KEEPS SHOWERS IN THE REGION
THROUGH THURSDAY WHEREAS THE GFS IS QUICKER TO DRY OUT. A WEAK
RIDGE WILL BRING DRIER WEATHER BACK INTO THE AREA WITH SEASONAL
TEMPS THROUGHOUT THE EXTENDED. MODEL GUIDANCE CONTINUES TO SHOW
LITTLE TO NO ARCTIC AIR MOVING IN WITH FRONT SO AT THIS POINT WE
DONT EXPECT ANY SURGES OF COLD AIR INTO THE REGION THROUGH THE
LATE WEEK NEXT WEEK.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
THROUGH 12Z SATURDAY...CONDITIONS WILL VARY FROM SITE TO SITE
THROUGH THE PERIOD. EXPECT MVFR CONDITIONS PREVAILING WITH BOUTS
OF IFR SNOW SHOWERS IN THE CHAMPLAIN VALLEY AND AT KMPV. MVFR
CONDITIONS LIFTING TO VFR IN THE AFTERNOON TOMORROW AT KRUT. IFR
CEILINGS WILL PERSIST THROUGH THE EARLY MORNING AT KMSS AND MVFR
CONDITIONS WITH PERIODS OF IFR CEILING WILL OCCUR AT KSLK. AS THE
SURFACE LOW CONTINUES TO JUST SLOWLY MEANDER AROUND THERE WILL BE
SOME SCATTED LIGHT SNOW SHOWER MAINLY IN THE CHAMPLAIN VALLEY
OVERNIGHT. AFTER 18Z THERE WILL BE AN ENHANCED SURGE OF SNOW
SHOWERS DURING THE AFTERNOON AT THE NORTHERN VT SITES. FOR KMSS A
PERIOD OF LIGHT SHOWERS BROUGHT IN A PERIOD OF IFR VISIBILITIES
AND CONDITIONS ARE STARTING TO IMPROVE. EXPECT MVFR CEILINGS WITH
PERIODS OF IFR VIS ARE FZDZ AND SNOW FAIL THROUGH THE MORNING. WINDS
WILL CONTINUE TO REMAIN LIGHT NORTHERLY THROUGHOUT THE PERIOD.
OUTLOOK 12Z SATURDAY THROUGH WEDNESDAY...
12Z FRIDAY - 12Z SATURDAY...LOW PRESSURE BEGINS TO PULL NORTHEAST
OF THE REGION WITH PRECIPITATION BECOMING MORE SCATTERED...BUT
MVFR/IFR CONDITIONS LIKELY TO REMAIN IN LIGHT SNOW ESPECIALLY
ACROSS THE HIGHER TERRAIN.
12Z SATURDAY - 06Z SUNDAY...LINGERING MVFR TRENDING TO VFR AS
HIGH PRESSURE BUILDS ACROSS THE REGION.
06Z SUNDAY - 00Z WEDNESDAY...VFR CONDITIONS WITH DRIER WEATHER
EXPECTED.
00Z WEDNESDAY...MVFR WITH PERIOD OF IFR EXPECTED DUE TO SNOW
SHOWERS ASSOCIATED WITH AN ADVANCING LOW PRESSURE SYSTEM.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG
SHORT TERM...JMG
LONG TERM...DEAL
AVIATION...DEAL
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
632 AM EST FRI DEC 12 2014
.SYNOPSIS...
NEARLY STATIONARY LOW PRESSURE WILL REMAIN ATOP THE REGION THROUGH
SATURDAY BEFORE SLOWLY PULLING EAST AND LOSING INFLUENCE ON DAILY
WEATHER CONDITIONS BY SATURDAY NIGHT INTO SUNDAY. SCATTERED TO
NUMEROUS SNOW SHOWERS WILL REMAIN PREVALENT ACROSS THE NORTH TODAY
INTO TONIGHT BEFORE SENSIBLE WEATHER TRENDS DRIER THROUGH THE DAY ON
SATURDAY. TEMPERATURES WILL REMAIN VERY SIMILAR TO READINGS OVER THE
PAST FEW DAYS...HOLDING SLIGHTLY ABOVE EARLY WINTER NORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 632 AM EST FRIDAY...GOING FORECAST REMAINS IN GOOD SHAPE.
ADJUSTED HOURLY T/TD DATASETS TO MATCH CURRENT OBSERVATIONAL
TRENDS, OTHERWISE LITTLE CHANGES WERE NEEDED AS OF 600 AM.
WATCHING SCATTERED AREAS OF LIGHT SNOW/SHSN/FLURRIES CONTINUING TO
SINK SOUTHWARD INTO CENTRAL AND NRN PORTIONS OF THE FORECAST AREA
AND STILL EXPECT THIS ACTIVITY TO CONTINUE ON AND OFF FOR A GOOD
PORTION OF THE DAY IN THESE AREAS WITH A GENERAL DUSTING TO 2
INCHES EXPECTED. HIGHEST AMOUNTS IN THE NRN MTNS OF VT. PRIOR
DISCUSSION FOLLOWS. HAVE A GREAT DAY.
PRIOR DISCUSSION FROM 330 AM EST FRIDAY...
BROKEN RECORD FORECAST CONTINUES TODAY INTOTONIGHT WITH
STATIONARY OCCLUSION REMAINING ATOP OR JUST EAST OF THE FORECAST
AREA. MOIST CYCLONIC FLOW COMBINED WITH WEAK SHORTWAVE ENERGY
BUNDLES DROPPING SOUTHWARD WILL COMBINE TO KEEP SCATTERED TO
NUMEROUS SNOW SHOWERS OR PERIODS OF LIGHT SNOW ONGOING ACROSS MUCH
OF OUR CENTRAL AND NORTHERN COUNTIES...ESPECIALLY FROM THE
ADIRONDACKS EASTWARD. SOME MINOR ADDITIONAL ACCUMULATIONS
LIKELY...SIMILAR TO YESTERDAY AND ESPECIALLY ACROSS THE HIGHER
TERRAIN WHERE SFC TEMPERATURES WILL BE A FEW DEGREES COOLER. LESS
OVERALL COVERAGE ACROSS THE SOUTHERN VALLEYS. ALSO INTRODUCED THE
CHANCE FOR SOME INTERMITTENT -FZDZ ACROSS OUR FAR WESTERN COUNTIES
WHERE RAP SOUNDING PROFILES SUGGEST AN UNSATURATED SNOW GROWTH
ZONE THROUGH LATE MORNING/EARLY AFTERNOON. SIMILAR TO THE UPPER
PATTERN...TEMPERATURES ALSO GOING NOWHERE AND NEARLY IDENTICAL TO
READINGS OVER THE PAST FEW DAYS HOLDING IN THE UPPER 20S TO MID
30S DURING THE DAY AND SETTLING BACK INTO THE 20S OVERNIGHT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
AS OF 330 AM EST FRIDAY...BY SATURDAY MODEL SUITE SHOWING GOOD
CONSENSUS THAT OUR PESKY UPPER LOW WILL SLOWLY BEGIN TO PULL
EASTWARD SUCH THAT DEEPER MOISTURE AND OVERALL INFLUENCE WILL WANE
OVER TIME. STILL COULD SEE SOME LINGERING NRN MTN FLURRY/SHSN
ACTIVITY HERE AND THERE...BUT AREAL COVERAGE WILL BY AND LARGE BE
LESS THAN TODAY WITH BROADER VALLEYS MAINLY DRY. LIGHT WINDS AND
LACK OF THERMAL ADVECTIVE PROCESSES MEAN NO AIRMASS CHANGE SO HIGH
TEMPERATURES...YOU GUESSED IT...NEARLY IDENTICAL TO TODAY IN THE
UPPER 20S TO MID 30S.
BY SATURDAY NIGHT UPPER LEVEL RIDGING TO OUR WEST FINALLY BEGINS TO
MAKE INROADS EAST AS UPPER LOW CONTINUES TO PULL SLOWLY AWAY
OFFSHORE. A SOMEWHAT TRICKY CLOUD FORECAST WITH VARYING SOLUTIONS
OFFERED ON DEGREE OF COOLING. POTENTIAL BUST WITH MINIMUM
TEMPERATURES GIVEN POSSIBLE CLEARING AND FRESH SNOW COVER...SO WILL
LEAN CONSERVATIVELY TOWARD A BLEND OF AVBL GUIDANCE SHOWING VARIABLE
CLOUDS THINNING ONLY SLOWLY AND LOW TEMPS ABOUT 5 DEGREES COLDER
THAN TONIGHT...UPPER TEENS TO MID 20S OR SO.
ON SUNDAY DEEP LEVEL RIDGING MAKES FURTHER PROGRESS INTO THE REGION
WITH CONTINUED DRYING THROUGH THE PBL AND INCREASING AMOUNTS OF SUN
AS UPPER FLOW TRENDS ANTICYCLONIC/SUBSIDENT. 850 MB RESPOND AND
RANGE FROM 0C TO +5C EAST TO WEST ACROSS THE AREA BY AFTERNOON.
HOWEVER A LIGHT NORTHERLY FLOW ALONG WITH A SHALLOW MIXED LAYER
TO ONLY 1500 FEET OR SO WILL KEEP TEMPERATURES COOLER THAN WHAT
THOSE READINGS WOULD NORMALLY INDICATE WITH MOST SPOTS TOPPING OUT
ONLY IN THE 30S. STILL QUITE A NICE DAY THOUGH WITH THE SUNSHINE
BEING WELCOME AFTER NEARLY A WEEK OF HIDING.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 330 AM EST FRIDAY...A BUILDING UPPER LEVEL RIDGE WILL BRING
DRY WEATHER TO THE AREA EARLY NEXT WEEK. THAT HIGH PRESSURE WILL
BE SHORT LIVED AS WEAKLY NEGATIVELY TILTED TROUGH WILL PUSH INTO
THE AREA. THERE IS INCREASING CONSENSUS THAT SNOWS SHOWERS WILL
RETURN ON WEDNESDAY AS THE WEAK COLD FRONT CROSSES THE REGION.
DURING THE DAY ON WEDNESDAY THE MODELS DIVULGE WITH THE GFS
BRINGING A WEAKER UPPER LEVEL LOW AND THE ECMWF BRINGING A MORE
ROBUST SYSTEM THROUGH. THE ECMWF KEEPS SHOWERS IN THE REGION
THROUGH THURSDAY WHEREAS THE GFS IS QUICKER TO DRY OUT. A WEAK
RIDGE WILL BRING DRIER WEATHER BACK INTO THE AREA WITH SEASONAL
TEMPS THROUGHOUT THE EXTENDED. MODEL GUIDANCE CONTINUES TO SHOW
LITTLE TO NO ARCTIC AIR MOVING IN WITH FRONT SO AT THIS POINT WE
DONT EXPECT ANY SURGES OF COLD AIR INTO THE REGION THROUGH THE
LATE WEEK NEXT WEEK.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
THROUGH 06Z SATURDAY...CONDITIONS WILL VARY FROM SITE TO SITE
THROUGH THE PERIOD. EXPECT MVFR CONDITIONS PREVAILING WITH BOUTS
OF IFR SNOW SHOWERS IN THE CHAMPLAIN VALLEY AND AT KMPV. MVFR
CONDITIONS LIFTING TO VFR IN THE AFTERNOON TOMORROW AT KRUT. IFR
CEILINGS WILL PERSIST THROUGH THE EARLY MORNING AT KMSS AND MVFR
CONDITIONS WITH PERIODS OF IFR CEILING WILL OCCUR AT KSLK. AS THE
SURFACE LOW CONTINUES TO JUST SLOWLY MEANDER AROUND THERE WILL BE
SOME SCATTED LIGHT SNOW SHOWER MAINLY IN THE CHAMPLAIN VALLEY
OVERNIGHT. AFTER 18Z THERE WILL BE AN ENHANCED SURGE OF SNOW
SHOWERS DURING THE AFTERNOON AT THE NORTHERN VT SITES. FOR KMSS
THE SNOW GROWTH ZONE CONTINUES TO BE UNSATURATED SO I CARRIED FZDZ
THROUGH 09Z AS THERE WILL BE SOME LIGHT MISTY FREEZING PRECIP.
WINDS WILL CONTINUE TO REMAIN LIGHT NORTHERLY THROUGHOUT THE
PERIOD.
OUTLOOK 06Z SATURDAY THROUGH TUESDAY...
06Z FRIDAY - 12Z SATURDAY...LOW PRESSURE BEGINS TO PULL NORTHEAST
OF THE REGION WITH PRECIPITATION BECOMING MORE SCATTERED...BUT
MVFR/IFR CONDITIONS LIKELY TO REMAIN IN LIGHT SNOW ESPECIALLY
ACROSS THE HIGHER TERRAIN.
12Z SATURDAY - 06Z SUNDAY...LINGERING MVFR TRENDING TO VFR AS
HIGH PRESSURE BUILDS ACROSS THE REGION.
06Z SUNDAY - 12Z TUESDAY...VFR CONDITIONS WITH DRIER WEATHER
EXPECTED.
12Z TUESDAY ONWARD...CHANCE FOR MVFR AND IFR IN SNOW ASSOCIATED
WITH LOW PRESSURE SYSTEM CROSSING THE NORTH COUNTRY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG
SHORT TERM...JMG
LONG TERM...DEAL
AVIATION...DEAL/LOCONTO
AREA FORECAST DISCUSSION
NWS BUFFALO NY
622 AM EST FRI DEC 12 2014
.SYNOPSIS...
A STALLED LOW PRESSURE SYSTEM WILL CONTINUE TO SPIN AND WEAKEN
ACROSS NEW ENGLAND TODAY AND WILL STILL PRODUCE A LITTLE VERY LIGHT
SNOW OR EVEN SOME FREEZING DRIZZLE. THIS WILL FINALLY END BY
SATURDAY AS HIGH PRESSURE BUILDS INTO THE OHIO VALLEY AND LOWER
LAKES REGION WITH DRY WEATHER LASTING THROUGH THE WEEKEND.
TEMPERATURES WILL BEGIN TO MODERATE TO ABOVE AVERAGE ESPECIALLY
SUNDAY INTO THE FIRST HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR IMAGERY EARLY THIS MORNING CONTINUES TO SHOW SOME VERY WEAK
RETURNS ACROSS WESTERN NY INDICATIVE OF FLURRIES FALLING IN THE FORM
OF VERY FINE GRAINS SOMETIMES CALLED SNIZZLE. A MORE PERSISTENT AREA
OF RETURNS IS STILL FOUND ACROSS CHAUTAUQUA AND WESTERN CATTARAUGUS
COUNTY IN WHAT REMAINS OF THE OLD DEFORMATION AXIS FROM YESTERDAY.
THE CHAUTAUQUA COUNTY DISPATCH AND SPOTTER REPORTS INDICATE THAT
SOME OF THIS IS FALLING AS FREEZING DRIZZLE. BUFKIT POINT SOUNDINGS
BEAR THIS OUT WITH MOISTURE BECOMING TOO SHALLOW AND WARM TO ALLOW
FOR ICE NUCLEI IN THE CLOUD LAYER. LATEST MESOSCALE MODEL GUIDANCE
SUCH AS THE NAM AND HRRR SUGGEST THIS AREA OF PERSISTENT LIGHT
PRECIP WILL CONTINUE INTO THE MORNING ACROSS THE CHAUTAUQUA
RIDGE...AND WITH THIS IN MIND WE HAVE EXTENDED THE ADVISORY THROUGH
MID MORNING TO COVER THE LINGERING FREEZING DRIZZLE AND POTENTIAL
FOR SLICK SPOTS DURING THE MORNING DRIVE ON UNTREATED SURFACES.
OTHERWISE FOR THE REST OF THE AREA EXPECT A MAINLY DRY MORNING WITH
JUST A FEW VERY LIGHT FLURRIES. A FEW PATCHES OF FREEZING DRIZZLE
ARE POSSIBLE ELSEWHERE AS WELL...BUT THIS SHOULD REMAIN TOO LIGHT
AND ISOLATED TO HAVE ANY MEANINGFUL IMPACT.
THE VERTICALLY STACKED AREA OF LOW PRESSURE OVER NEW ENGLAND WILL
CONTINUE TO DRIFT SLOWLY EAST TODAY AND TONIGHT WITH ANY LINGERING
ASCENT AND DEEPER MOISTURE SLOWLY BEING STRIPPED AWAY FROM WEST TO
EAST. THE REMAINING WEAK DEFORMATION AXIS ACROSS THE WESTERN
SOUTHERN TIER WILL BREAK DOWN THROUGH THE COURSE OF THE DAY AS
SUBSIDENCE AND DRYING CONTINUE. THIS SHOULD ALLOW THE VERY LIGHT
SNOW AND FREEZING DRIZZLE TO SLOWLY END.
EAST OF LAKE ONTARIO ONE LAST SUBTLE MID LEVEL TROUGH WILL DROP
SOUTH AROUND THE MID LEVEL LOW TODAY...AND THIS COMBINED WITH MOIST
NORTHWEST UPSLOPE FLOW MAY PRODUCE A FEW LIGHT SNOW SHOWERS FROM
MIDDAY THOUGH THE AFTERNOON. INVERSION HEIGHTS ARE TOO LOW TO
SUPPORT ANY LAKE EFFECT SOUTHEAST OF EITHER LAKE EXCEPT FOR A FEW
FLURRIES OF NO CONSEQUENCE.
MOST OF THE PRECIP WILL END TONIGHT...ALTHOUGH A FEW FLURRIES OR
LIGHT SNOW SHOWERS MAY PERSIST ACROSS CENTRAL NY AND THE NORTH
COUNTRY. MOISTURE WILL BECOME QUITE SHALLOW AGAIN...SO THERE MAY BE
SOME LIMITED CHANCE FOR FREEZING DRIZZLE TO MIX IN AS WELL.
EXTENSIVE LOW LEVEL MOISTURE IS TRAPPED BENEATH A STEEPENING LOW
LEVEL INVERSION. UPSTREAM OBS SHOW PLENTY OF LOW CLOUDS STILL
UPSTREAM...AND THIS COMBINED WITH THE PATTERN RECOGNITION OF WEAK
NORTHWEST FLOW IN DECEMBER DOES NOT BODE WELL FOR ANY CLEARING
THROUGH TONIGHT WITH LOW CLOUDS DOMINATING IN MOST AREAS.
EXPECT HIGHS TODAY TO REACH THE LOWER 30S ON THE LAKE PLAINS WITH
UPPER 20S ON THE HILLS. THE CLOUDS TONIGHT WILL PREVENT MUCH
RADIATIONAL COOLING...WITH MID 20S IN MOST AREAS AND UPPER TEENS TO
LOWER 20S ACROSS THE NORTH COUNTRY.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
THE LOW PRESSURE SYSTEM THAT HAS AFFECTED THE NORTHEAST THROUGHOUT
MUCH OF THE WEEK WILL FINALLY BE EXITING THE REGION AS WE MOVE INTO
FRIDAY NIGHT. THAT SAID...WE MAY STILL HAVE TO CONTEND WITH SOME
VERY LIGHT PRECIPITATION THANKS TO PERSISTENT WEST-NORTHWEST
ONSHORE/UPSLOPE FLOW AND LINGERING LOW-LEVEL MOISTURE TRAPPED
BENEATH A STRENGTHENING SUBSIDENCE INVERSION ALOFT...ITSELF THE
PRODUCT OF INCREASING RIDGING ALOFT. GIVEN THE EXTENSIVE DRYING
ALOFT...THERE IS CONSIDERABLE UNCERTAINTY AS TO WHETHER THERE WILL
BE MUCH IN THE WAY OF PRECIPITATION FROM THE LOW STRATUS EXPECTED TO
LINGER...HOWEVER SHOULD ANY OCCUR THE GREATEST CHANCES WILL BE FOUND
SOUTHEAST OF LAKE ONTARIO...WHERE THE MOISTURE-BEARING FETCH WILL BE
GREATEST. WITH REGARDS TO PRECIPITATION TYPE...THE SHALLOW NATURE OF
THE MOISTURE AND SUBSIDENCE ALOFT WILL RENDER THE DENDRITIC SNOW
GROWTH LAYER VERY DRY...SUGGESTING P-TYPE WILL BE MAINLY FREEZING
DRIZZLE AS TEMPERATURES WILL RUNNING IN THE 20S.
POPS WILL CONTINUE TO DIMINISH FROM WEST TO EAST ON SATURDAY AS
RIDGING AND SUBSIDENCE CONTINUES TO STRENGTHEN OVER THE REGION.
NONETHELESS...WE WILL LIKELY CONTINUE TO SEE FAIRLY EXTENSIVE CLOUD
COVER ACROSS THE REGION AS GENERAL FLOW WILL REMAIN WESTERLY AND
MOISTURE WILL REMAIN TRAPPED UNDER THE PERSISTENT SUBSIDENCE
INVERSION. TEMPERATURES WILL REMAIN ON THE COOL SIDE OF AVERAGE WITH
HIGHS IN THE 30S...WITH COOLER READINGS IN THE NORTH
COUNTRY...CLOSER TO THE EXITING UPPER LEVEL LOW.
THE UPPER LEVEL RIDGE MOVES OVERHEAD FOR THE SECOND HALF OF THE
WEEKEND...BRINGING SOMEWHAT WARMER TEMPERATURES ALOFT...HOWEVER WITH
FLOW IN THE LOWEST LEVELS OF THE ATMOSPHERE REMAINING STUBBORNLY OUT
OF THE WEST-NORTHWEST...CLOUD COVER AND COOLER TEMPERATURES WILL
LIKELY PREVAIL IN SPITE OF WARMING ALOFT...PARTICULARLY SHOULD
EXPECTED LOW CLOUDS...STILL TRAPPED UNDER THE INVERSION...REMAIN IN
PLACE AS CURRENTLY EXPECTED. LOOK FOR HIGHS TO TOP OUT IN THE MID TO
UPPER 30S SUNDAY WITH LOW TO MID 30S SUNDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
IT SHOULD BE A DRY START TO THE WEEK MONDAY INTO MONDAY NIGHT AS
HIGH PRESSURE REMAINS FIRMLY IN CONTROL OF THE REGION. THE
PERSISTENT SPLIT-FLOW PATTERN OF LATE WILL CONTINUE INTO NEXT WEEK
AND AS WE MOVE INTO TUESDAY...PRECIP CHANCES WILL BEGIN TO RAMP UP
ONCE AGAIN ACROSS THE REGION AS A FAST-MOVING SOUTHERN STREAM LOW
TRACKS ACROSS THE OHIO VALLEY AND THE LOWER GREAT LAKES. THE
FORECAST AREA WILL BE CLOSE TO THE RAIN-SNOW LINE AND WILL KEEP A
MENTION OF BOTH TYPES GIVEN UNCERTAINTIES INHERENT THIS FAR OUT IN
THE FORECAST. TEMPERATURES WILL LIKELY RUN NEAR AVERAGE MONDAY AND
TUESDAY AS WE SHOULD FINALLY REALIZE ENOUGH SOUTHERLY FLOW AHEAD OF
THIS SYSTEM TO CHASE AWAY THE LOW-LEVEL COLD AIR AND LOW CLOUDS.
LOOKING LATER IN THE WEEK...THERE IS A CONSIDERABLE UNCERTAINTY
REGARDING A NORTHERN STREAM UPPER LOW POISED TO DROP DOWN OUT OF
THE CANADIAN ROCKIES TUESDAY INTO WEDNESDAY. THIS SYSTEM WILL
LIKELY USHER IN A RETURN TO COOLER TEMPERATURES BY THE LATTER HALF
OF THE WEEK...THOUGH GIVEN THE LACK OF MOISTURE...PRECIPITATION IS
NOT EXPECTED TO BE SIGNIFICANT.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
A FEW FLURRIES AND LIGHT SNOW SHOWERS WILL CONTINUE TODAY ACROSS
PORTIONS OF THE REGION. THIS MAY BRIEFLY DROP VSBY DOWN TO MVFR IN A
FEW SPOTS. SOME FREEZING DRIZZLE WILL ALSO MIX IN AT TIMES...MAINLY
THIS MORNING ACROSS WESTERN NY. WIDESPREAD MVFR CIGS WILL CONTINUE
TODAY WITH IFR ACROSS HIGHER TERRAIN.
TONIGHT SCATTERED SNOW SHOWERS ACROSS CENTRAL NY AND THE NORTH
COUNTRY MAY DROP VSBY TO MVFR BRIEFLY THIS EVENING BEFORE TAPERING
OFF OVERNIGHT. OTHERWISE EXPECT MORE WIDESPREAD MVFR CIGS AT LOWER
ELEVATIONS AND IFR ACROSS HIGHER TERRAIN WITH A PERSISTENT LOW
STRATUS DECK.
OUTLOOK...
SATURDAY...AREAS OF MVFR CIGS.
SUNDAY AND MONDAY...VFR.
TUESDAY...AREAS OF MVFR IN RAIN AND SNOW SHOWERS.
&&
.MARINE...
MODERATE NORTHWEST FLOW WILL CONTINUE TO PRODUCE MARGINAL SMALL
CRAFT ADVISORY CONDITIONS ON BOTH LAKES ERIE AND ONTARIO TODAY AND
THIS EVENING. WINDS WILL THEN DIMINISH OVER THE WEEKEND AS HIGH
PRESSURE BUILDS INTO THE OHIO VALLEY WITH A RIDGE EXTENDING INTO THE
LOWER LAKES. RELATIVELY LIGHT WINDS WILL CONTINUE INTO EARLY NEXT
WEEK BEFORE AN AREA OF LOW PRESSURE CROSSES THE REGION BY TUESDAY
AND WEDNESDAY BRINGING WITH IT INCREASING WINDS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR
NYZ019-020.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST SATURDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 1 AM EST SATURDAY FOR
LOZ042.
SMALL CRAFT ADVISORY UNTIL 4 AM EST SATURDAY FOR LOZ043-
044.
&&
$$
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...CHURCH
LONG TERM...CHURCH
AVIATION...HITCHCOCK
MARINE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1246 PM EST SAT DEC 13 2014
.SYNOPSIS...SURFACE HIGH PRESSURE WILL REMAIN OVER THE REGION
THROUGH MONDAY. A COLD FRONT MOVES THROUGH THE REGION TUESDAY AND
TUESDAY NIGHT. HIGH PRESSURE THEN GRADUALLY BUILDS IN FROM THE WEST
ONCE AGAIN THROUGH THE END OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1245 PM SATURDAY...
THE LATEST SURFACE ANALYSIS SHOWED HIGH PRESSURE EXTENDING OVER
CENTRAL NORTH CAROLINA FROM THE WEST...WITH A SLACK GRADIENT. UPPER-
AIR ANALYSES SHOWED A QUITE DRY 850MB LEVEL...EVEN TO 700MB...AND
THE 12Z KGSO SOUNDING ONLY SHOWED A MODEST VOLUME OF MOISTURE JUST
BELOW 500MB. IN THE NORTHERLY FLOW ALOFT...SATELLITE IMAGERY
INDICATED PATCHY CIRRUS AND MID-LEVEL CLOUD MOSTLY DISSIPATING AS IT
TRIED TO MOVE SOUTH ACROSS VIRGINIA. DURING THE DAY...AS A WEAK MID-
LEVEL SHORTWAVE MOVES THROUGH CENTRAL NORTH CAROLINA...PATCHY MID-
AND HIGH-LEVEL CLOUDS SHOULD DEVELOP AS A JET ALOFT MOVES SOUTH JUST
OFFSHORE. THE CANADIAN CLOUD COVER MODEL HAS BEEN HANDLING SOME OF
THESE FEATURES WELL AND IT KEEPS THE LEAST AMOUNT OF THE PATCHINESS
TOWARD THE TRIAD. STILL...DURING THE DAY SUNNY TO MOSTLY SUNNY
CONDITIONS SHOULD BE THE AVERAGE. 925MB WINDS ARE FORECAST AROUND
15KT THIS AFTERNOON...AND RAP SOUNDINGS SHOW JUST A PERIOD THIS
AFTERNOON AROUND 20Z WHERE MIXING COULD BE ENOUGH TO PROVIDE FOR A
BRIEF GUST IN THE TEENS KTS. WITH GOOD SUNSHINE AND DRY BOUNDARY
LAYER AIR...AS DEWPOINTS WERE IN A WIDE RANGE FROM JUST ABOVE 10F TO
THE UPPER 20S...TEMPERATURES HAVE WARMED QUICKLY AND FOR AN EARLY
AFTERNOON UPDATE EDGED UP HIGHS PARTICULARLY IN THE WESTERN
PIEDMONT...WHILE KEPTS HIGHS AS THEY WERE OR EDGED MAYBE A DEGREE
LOWER TOWARD THE NORTHERN COASTAL PLAIN. TONIGHT...UNDER CLEAR SKIES
AND LIGHT TO CALM WINDS...GOOD RADIATIONAL COOLING WILL SUPPORT MIN
TEMPS A FEW DEGREES ON EITHER SIDE OF FREEZING.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 158 AM SUNDAY...
BOTH THE UPPER LEVEL AND SURFACE RIDGE AXIS OVER THE TN VALLEY WILL
CONTINUE TO BUILD EASTWARD...BECOMING CENTERED OVER THE AREA SUNDAY
NIGHT/EARLY MONDAY. RESULTANT DEEP LAYER SUBSIDENCE WILL SECURE DRY
CONDITIONS AND SUNNY/CLEAR SKIES...WHILE MAINTAINING LOW MIXING
HEIGHTS. HIGHS FOR THE THIRD STRAIGHT DAY RANGING FROM THE MID/UPPER
50S NORTH TO LOWER 60S SOUTH. LOWS SUNDAY NIGHT...NOT QUITE AS COOL
AS SATURDAY NIGHT AS DEWPOINTS CONTINUE TO MODERATE. LOWS IN THE
LOWER 30S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 210 AM SATURDAY...
MONDAY AND TUESDAY: THE RIDGE OVER THE CAROLINAS ON MONDAY WILL
RESULT IN DRY WEATHER AND HIGHS IN THE MID TO UPPER 50S WITH
GENERALLY CLEAR SKIES. THE HIGH WILL PUSH EAST OFF THE COAST MONDAY
NIGHT INTO TUESDAY AS AN UPPER LEVEL SHORTWAVE TROUGH AND ASSOCIATED
SURFACE COLD FRONT APPROACH MONDAY NIGHT INTO TUESDAY. EXPECT
INCREASING CLOUDS MONDAY NIGHT AHEAD OF THE FRONT...WITH LOWS
GENERALLY IN THE MID 30S. THE MODELS STILL DIFFER QUITE A BIT WITH
REGARD TO RAIN AHEAD OF THE FRONT...WITH THE ECMWF BEING WET AND A
LITTLE FASTER...WHILE THE GFS REMAINS DRY. WILL KEEP THE SLIGHT
CHANCE OF RAIN IN THE FORECAST TUESDAY...WITH THE BEST CHANCES
CURRENTLY ACROSS THE NORTH NEAR THE NC/VA BORDER. DESPITE THE CLOUDY
SKIES AND SLIGHT CHANCE FOR RAIN...HIGHS TUESDAY EXPECTED TO BE IN
THE UPPER 50S TO LOW 60S GIVEN THE SW FLOW ADVECTING IN SOME WARM
AIR. LOWS TUESDAY NIGHT WILL DEPEND ON THE TIMING OF THE FRONT...
BUT FOR NOW EXPECT LOWS GENERALLY IN THE MID 30S NW TO AROUND 40 SE.
WEDNESDAY THROUGH FRIDAY: AT THE SURFACE...HIGH PRESSURE WILL BUILD
INTO THE REGION BEHIND THE FRONT...WITH GENERALLY WEST-NORTHWEST
FLOW ON WEDNESDAY BECOMING GENERALLY NORTHERLY BY THE END OF THE
WEEK. HOWEVER...THE MODELS STILL VARY QUITE A BIT WITH THE UPPER
LEVEL FLOW...AS THE ECMWF HAS GENERALLY WEST-NORTHWEST FLOW OVER NC
WITH THE LOW OVER NEW ENGLAND...WHILE THE GFS HAS MORE OF A RIDGE
AND SOUTHWESTERLY FLOW OVER THE AREA WITH A LOW OVER THE MIDWEST.
THIS DIFFERENCE IN THE MODELS MAKES THE TEMPERATURE FORECAST A BIT
CHALLENGING AS THERE IS A 5-10 DEGREE DIFFERENCE BETWEEN THE TWO
MODELS. FOR NOW WILL LEAN MORE TOWARD HPC...WHICH FAVORS TEMPS A BIT
CLOSER TO THE GFS. EXPECT HIGHS GENERALLY IN THE 50S THROUGH THE END
OF THE WEEK...WITH LOWS IN THE 30S...BUT 32 OR ABOVE FOR THE MOST
PART...THE COLDEST NIGHT BEING WEDNESDAY NIGHT...GRADUALLY
MODERATING THROUGH THE END OF THE WEEK. WILL KEEP THE FORECAST DRY
THROUGH FRIDAY...BUT INTRODUCE A SLIGHT CHANCE FOR SOME RAIN FRIDAY
NIGHT...ALTHOUGH CONFIDENCE THIS FAR OUT IS LOW...ESPECIALLY GIVEN
THE MODEL DIFFERENCES.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 1245 PM SATURDAY...
VFR CONDITIONS CONTINUE THROUGH THE 18Z VALID TAF PERIOD. GENERALLY
NORTHWEST WINDS OF 5 TO 10KT WILL DIMINISH THIS EVENING AND BECOME
LIGHT...INCREASING AGAIN TO AROUND 5KT SUNDAY MORNING WHILE VEERING
SLIGHTLY. ANY CLOUDS WILL BE OF MID-TO-HIGH LEVEL PASSING THROUGH
CENTRAL NORTH CAROLINA FROM NORTH-TO-SOUTH.
BEYOND THE 18Z VALID TAF PERIOD...THERE IS SOME POTENTIAL FOR
PERIODS OF SUB-VFR CONDITIONS LATE MONDAY NIGHT THROUGH TUESDAY
AHEAD OF A COLD FRONT THAT WILL MOVE THROUGH CENTRAL NORTH CAROLINA
LATE TUESDAY. SOUTHWEST WINDS ALOFT WILL INCREASE DURING THAT TIME
AS WELL...WITH SOME SOUTHWEST WINDS AROUND 40KT POSSIBLE BY 3000FT
TO 4000FT. VFR CONDITIONS ARE ANTICIPATED LATE SUNDAY THROUGH
MOST OF MONDAY NIGHT...AND AGAIN WEDNESDAY THROUGH THURSDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...CBL/DJF
SHORT TERM...CBL
LONG TERM...KC
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
945 AM EST SAT DEC 13 2014
.SYNOPSIS...HIGH PRESSURE WILL BUILD SLOWLY INTO OUR AREA FROM THE
WEST THROUGH THE WEEKEND...AND PASS OVERHEAD ON MONDAY...BEFORE
MOVING OFFSHORE MONDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM SATURDAY...
THE LATEST SURFACE ANALYSIS SHOWED HIGH PRESSURE EXTENDING OVER
CENTRAL NORTH CAROLINA FROM THE WEST...WITH A SLACK GRADIENT. UPPER-
AIR ANALYSES SHOWED A QUITE DRY 850MB LEVEL...EVEN TO 700MB...AND
THE 12Z KGSO SOUNDING ONLY SHOWED A MODEST VOLUME OF MOISTURE JUST
BELOW 500MB. IN THE NORTHERLY FLOW ALOFT...SATELLITE IMAGERY
INDICATED PATCHY CIRRUS AND MID-LEVEL CLOUD MOSTLY DISSIPATING AS IT
TRIED TO MOVE SOUTH ACROSS VIRGINIA. DURING THE DAY...AS A WEAK MID-
LEVEL SHORTWAVE MOVES THROUGH CENTRAL NORTH CAROLINA...PATCHY MID-
AND HIGH-LEVEL CLOUDS SHOULD DEVELOP AS A JET ALOFT MOVES SOUTH JUST
OFFSHORE. THE CANADIAN CLOUD COVER MODEL HAS BEEN HANDLING SOME OF
THESE FEATURES WELL AND IT KEEPS THE LEAST AMOUNT OF THE PATCHINESS
TOWARD THE TRIAD. STILL...DURING THE DAY SUNNY TO MOSTLY SUNNY
CONDITIONS SHOULD BE THE AVERAGE. 925MB WINDS ARE FORECAST AROUND
15KT THIS AFTERNOON...AND RAP SOUNDINGS SHOW JUST A PERIOD THIS
AFTERNOON AROUND 20Z WHERE MIXING COULD BE ENOUGH TO PROVIDE FOR A
BRIEF GUST IN THE TEENS KTS. MAINTAINED THE TEMPERATURE FORECAST AS
IS FOR NOW ON THE HIGH SIDE OF GUIDANCE...CONSISTENT WITH 1000-850MB
THICKNESSES AND WITH A FEW OBSERVATIONS JUMPING QUICKLY INTO THE MID
40S WITH JUST A LITTLE WIND AND MIXING ALREADY AT 9 AM. TONIGHT...
UNDER CLEAR SKIES AND LIGHT TO CALM WINDS...GOOD RADIATIONAL COOLING
WILL SUPPORT MIN TEMPS A FEW DEGREES ON EITHER SIDE OF FREEZING.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 158 AM SUNDAY...
BOTH THE UPPER LEVEL AND SURFACE RIDGE AXIS OVER THE TN VALLEY WILL
CONTINUE TO BUILD EASTWARD...BECOMING CENTERED OVER THE AREA SUNDAY
NIGHT/EARLY MONDAY. RESULTANT DEEP LAYER SUBSIDENCE WILL SECURE DRY
CONDITIONS AND SUNNY/CLEAR SKIES...WHILE MAINTAINING LOW MIXING
HEIGHTS. HIGHS FOR THE THIRD STRAIGHT DAY RANGING FROM THE MID/UPPER
50S NORTH TO LOWER 60S SOUTH. LOWS SUNDAY NIGHT...NOT QUITE AS COOL
AS SATURDAY NIGHT AS DEWPOINTS CONTINUE TO MODERATE. LOWS IN THE
LOWER 30S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 210 AM SATURDAY...
MONDAY AND TUESDAY: THE RIDGE OVER THE CAROLINAS ON MONDAY WILL
RESULT IN DRY WEATHER AND HIGHS IN THE MID TO UPPER 50S WITH
GENERALLY CLEAR SKIES. THE HIGH WILL PUSH EAST OFF THE COAST MONDAY
NIGHT INTO TUESDAY AS AN UPPER LEVEL SHORTWAVE TROUGH AND ASSOCIATED
SURFACE COLD FRONT APPROACH MONDAY NIGHT INTO TUESDAY. EXPECT
INCREASING CLOUDS MONDAY NIGHT AHEAD OF THE FRONT...WITH LOWS
GENERALLY IN THE MID 30S. THE MODELS STILL DIFFER QUITE A BIT WITH
REGARD TO RAIN AHEAD OF THE FRONT...WITH THE ECMWF BEING WET AND A
LITTLE FASTER...WHILE THE GFS REMAINS DRY. WILL KEEP THE SLIGHT
CHANCE OF RAIN IN THE FORECAST TUESDAY...WITH THE BEST CHANCES
CURRENTLY ACROSS THE NORTH NEAR THE NC/VA BORDER. DESPITE THE CLOUDY
SKIES AND SLIGHT CHANCE FOR RAIN...HIGHS TUESDAY EXPECTED TO BE IN
THE UPPER 50S TO LOW 60S GIVEN THE SW FLOW ADVECTING IN SOME WARM
AIR. LOWS TUESDAY NIGHT WILL DEPEND ON THE TIMING OF THE FRONT...
BUT FOR NOW EXPECT LOWS GENERALLY IN THE MID 30S NW TO AROUND 40 SE.
WEDNESDAY THROUGH FRIDAY: AT THE SURFACE...HIGH PRESSURE WILL BUILD
INTO THE REGION BEHIND THE FRONT...WITH GENERALLY WEST-NORTHWEST
FLOW ON WEDNESDAY BECOMING GENERALLY NORTHERLY BY THE END OF THE
WEEK. HOWEVER...THE MODELS STILL VARY QUITE A BIT WITH THE UPPER
LEVEL FLOW...AS THE ECMWF HAS GENERALLY WEST-NORTHWEST FLOW OVER NC
WITH THE LOW OVER NEW ENGLAND...WHILE THE GFS HAS MORE OF A RIDGE
AND SOUTHWESTERLY FLOW OVER THE AREA WITH A LOW OVER THE MIDWEST.
THIS DIFFERENCE IN THE MODELS MAKES THE TEMPERATURE FORECAST A BIT
CHALLENGING AS THERE IS A 5-10 DEGREE DIFFERENCE BETWEEN THE TWO
MODELS. FOR NOW WILL LEAN MORE TOWARD HPC...WHICH FAVORS TEMPS A BIT
CLOSER TO THE GFS. EXPECT HIGHS GENERALLY IN THE 50S THROUGH THE END
OF THE WEEK...WITH LOWS IN THE 30S...BUT 32 OR ABOVE FOR THE MOST
PART...THE COLDEST NIGHT BEING WEDNESDAY NIGHT...GRADUALLY
MODERATING THROUGH THE END OF THE WEEK. WILL KEEP THE FORECAST DRY
THROUGH FRIDAY...BUT INTRODUCE A SLIGHT CHANCE FOR SOME RAIN FRIDAY
NIGHT...ALTHOUGH CONFIDENCE THIS FAR OUT IS LOW...ESPECIALLY GIVEN
THE MODEL DIFFERENCES.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 630 AM SATURDAY...
24 HOUR TAF PERIOD: THERE IS HIGH CONFIDENCE THAT VFR CONDITIONS
WILL CONTINUE FOR THE 24 HOUR TAF PERIOD...AS SURFACE HIGH PRESSURE
SLOWLY BUILDS INTO THE AREA...UNDERNEATH DRY NWLY FLOW ALOFT.
WINDS WILL REMAIN LIGHT AND FROM THE NW AT 5 TO 7KTS.
OUTLOOK: VFR CONDITIONS SHOULD PERSIST THROUGH MONDAY NIGHT. A COLD
FRONT IS EXPECTED TO MOVE THROUGH THE AREA TUESDAY AFTERNOON.
MOISTURE IS LIMITED WITH THE FRONT SO AVIATION IMPACTS ARE EXPECTED
TO BE MARGINAL WITH PERHAPS A BRIEF PERIOD OF SUB-VFR CIGS AND
POSSIBLY A QUICK PASSING SHOWER. VFR CONDITIONS ARE EXPECTED TO
RETURN FOR TUESDAY NIGHT INTO WEDNESDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...CBL/DJF
SHORT TERM...CBL
LONG TERM...KC
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
107 PM EST FRI DEC 12 2014
.SYNOPSIS...HIGH PRESSURE WILL GRADUALLY BUILD INTO OUR AREA FROM
THE WEST THROUGH THE WEEKEND...AND PASS OVERHEAD ON MONDAY...BEFORE
MOVING OFFSHORE MONDAY NIGHT.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 850 AM FRIDAY...
THE LATEST WATER VAPOR IMAGERY SHOWED A MID-LEVEL WAVE MOVING
THROUGH CENTRAL NORTH CAROLINA THAT HELPED PRODUCE SOME OROGRAPHIC
CIRRUS TOWARD THE TRIAD AND MID-LEVEL CLOUDINESS TOWARD THE NORTHERN
COASTAL PLAIN. THE RAP PLAN VIEW LAYER MOISTURE PRODUCTS SEEMED TO
BE DEPICTING THE TREND OF THESE CLOUDS FAIRLY WELL. AS THE MID-LEVEL
WAVE PASSES THROUGH AS IT IS CURRENTLY...AND AS FORECAST BY THE
RAP...THE HIGH-LEVEL CLOUDS TOWARD THE TRIAD SHOULD GRADUALLY WANE.
AN INCREASE IN MID-LEVEL CLOUDINESS TOWARD THE NORTHEAST PIEDMONT
AND THE NORTHERN COASTAL PLAIN WILL ALSO WANE AS THE CLOUDS MOVE
SOUTHEAST ALONG THE THE WAVE. AREA UPPER-AIR SOUNDINGS THAT SHOW
WINDS OFF OF THE SURFACE TO AROUND 25KT...AND FORECAST 925MB WINDS
TO 20KT ALONG WITH 850MB TO 30KT SHOULD ALLOW FOR SOME GUSTINESS OF
THE WINDS WITH MIXING...WITH RAP SOUNDINGS GENERALLY SUPPORTIVE OF
GUSTS IN THE TEENS KNOTS WITH MIXING. MORNING AND FORECAST
THICKNESSES WOULD SUGGEST HIGHS NEARER THE HIGHER MAV MOS
GUIDANCE...AND WILL WATCH TRENDS DURING THE MORNING AND POSSIBLY
RAISE MAXES A DEGREE OR TWO FOR THE PLANNED LATE-MORNING UPDATE. -DJF
BY TONIGHT WE SHOULD SEE ANOTHER ROUND OF HIGH THIN CLOUDS...THIS
TIME RESULTING FROM ADVECTION OF MOISTURE CURRENTLY OVER ONTARIO.
BUT AGAIN... ALL INDICATIONS ARE THAT THESE HIGH CLOUDS WILL BE THIN
AND LARGELY CONFINED TO THE NORTHERN HALF OF NC WITH DIFFLUENT FLOW
AND SUBSIDENCE PERSISTING ALOFT. WITH WINDS GOING CALM (OR NEARLY
SO) WITH GOOD DECOUPLING AND SCANT CLOUDINESS... WILL GO A BIT BELOW
STATISTICAL GUIDANCE FOR LOWS... 27-31.
FOR SAT/SAT NIGHT: MORE OF THE SAME. THE SURFACE HIGH OVER WRN KY/TN
WILL CONTINUE TO PUSH SLOWLY EAST... BANKING UP AGAINST THE WEST
SLOPES OF THE SRN APPALACHIANS THROUGH SAT NIGHT... AND WITH THE
SURFACE LOW OVER THE NORTHEAST HAVING DRIFTED FURTHER EAST AND
OFFSHORE... THE MSLP GRADIENT WILL STEADILY SLACKEN. AGAIN EXPECT
NOTHING MORE THAN PASSING HIGH THIN CLOUDS ON SAT. THE MIXED LAYER
GETS EVEN SHALLOWER WITH ONGOING SINKING OF THE VERY WARM LAYER JUST
OFF THE SURFACE... AND THE THERMAL PROFILE SUPPORTS SLIGHTLY ABOVE
NORMAL HIGHS OF 53-59. HAVE STAYED JUST UNDER GUIDANCE FOR LOWS ONCE
AGAIN WITH EXPECTATIONS OF GOOD RADIATIONAL COOLING. LOWS SAT NIGHT
28-33. -GIH
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 230 AM FRIDAY...
A DEEP HIGH AMPLITUDE RIDGE WILL BUILD OVER THE EASTERN CONUS
INCLUDING CENTRAL NC ON SUNDAY AND THEN MOVE EAST OF THE AREA ON
MONDAY. NORMALLY THIS PATTERN WOULD SIGNAL A WARMING TREND BUT CLEAR
SKIES ON SUNDAY WILL BE REPLACED WITH SOME UPPER LEVEL CLOUDINESS ON
MONDAY AND MAX TEMPS WILL ACTUALLY FALL A FEW DEGREES ON MONDAY
ALTHOUGH NOT MUCH. EXPECT MAX TEMPS BOTH DAYS IN THE MID TO UPPER
50S TO NEAR 60 DEGREES WITH MONDAY SLIGHTLY COOLER THAN SUNDAY. LOWS
WILL MODERATE FROM NEAR FREEZING ON MONDAY MORNING TO THE MIDDLE 30S
BY TUESDAY MORNING.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 230 AM FRIDAY...
SLOWER TIMING IN THE MODELS WITH REGARD TO THE LOW AND ASSOCIATED
COLD FRONT MOVING FROM THE WEST THE MIDDLE OF NEXT WEEK. THE SYSTEM
ALREADY HAD BAD DYNAMICS WITH IT AND NOW DIURNAL TIMING DOES NOT
LOOK VERY FAVORABLE AS IT IS NOW PROGGED TO COME THROUGH LATE
TUESDAY NIGHT INTO WEDNESDAY. THE RESULT IS THAT BOTH MODELS ARE NOW
VERY SPARSE WITH THE PRECIPIATION WITH THE RANGE FROM NONE TO A FEW
HUNDREDTHS OF AN INCH. TEMPERATURE MODERATION IS NOT GREAT AS COLD
AIR ADVECTION IS NEARLY NON-EXISTENT AS THE 500 MB PATTERN IS VERY
ZONAL. WITH THE LATER TIMING EXPECT TEMPS ON TUESDAY TO RISE INTO
THE UPPER 50S TO LOW 60S WITH LOWS IN THE UPPER 30S.
THE FRONT IS EXPECTED TO MOVE THROUGH BY WEDNESDAY MORNING AND MOVE
OUT OF THE AREA. THIS WILL ALLOW SKY CONDITIONS TO IMPROVE AND TEMPS
TO RISE INTO THE MID 50S WITH GOOD INSOLATION WEDNESDAY AFTERNOON
AND DROP INTO THE MIDDLE 30S WEDNESDAY NIGHT. ANOTHER SURFACE HIGH
WILL BUILD IN ON THURSDAY WITH A SMALL AMPLITUDE UPPER LEVEL RIDGE
APPROACHING FROM THE WEST. THIS ACTUALLY WILL INITIATE SOME DEEPER
LAYER COLD AIR ADVECTION AND TEMPS ON THURSDAY WILL BE A FEW DEGREES
COOLER...MAINLY LOWER 50S.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 105 PM FRIDAY...
VFR CONDITIONS CONTINUE FOR THE 18Z VALID TAF PERIOD. A MID-LEVEL
SHORTWAVE SHOULD MOVE THROUGH CENTRAL NORTH CAROLINA LATE TONIGHT
AND EARLY SATURDAY WHICH COULD INCREASE UPPER-LEVEL CLOUDS TO BROKEN
FOR A PERIOD...WITH THE HIGHER LIKELIHOOD OF THAT TOWARD THE TRIAD.
STILL...SOLIDLY VFR CONDITIONS EXPECTED UNDER A WIND THAT WILL VEER
NORTHWEST BY EVENING AND AVERAGE UNDER 5KT OVERNIGHT. WITH MIXING
SATURDAY MORNING...SURFACE WINDS SHOULD INCREASE TO BETWEEN 5 AND
10KT.
BEYOND THE 18Z VALID TAF PERIOD...VFR CONDITIONS SHOULD PERSIST
THROUGH MONDAY NIGHT. ON TUESDAY...THE GFS MODEL SUGGESTS THE
POTENTIAL FOR AREAS OF SUB-VFR CONDITIONS IN CLOUDS...LIKELY MVFR...
WITH ONLY A SLIGHT CHANCE OF SHOWERS AT PRESENT. SURFACE WINDS
REMAIN MOSTLY NORTHWEST AND SHOULD BECOME SOUTH TO SOUTHWEST ON
MONDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...DJF/HARTFIELD
SHORT TERM...ELLIS
LONG TERM...ELLIS
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
850 AM EST FRI DEC 12 2014
.SYNOPSIS...HIGH PRESSURE WILL GRADUALLY BUILD INTO OUR AREA FROM
THE WEST THROUGH THE WEEKEND... PASSING OVERHEAD ON MONDAY... BEFORE
MOVING OFFSHORE MONDAY NIGHT.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
AS OF 850 AM FRIDAY...
THE LATEST WATER VAPOR IMAGERY SHOWED A MID-LEVEL WAVE MOVING
THROUGH CENTRAL NORTH CAROLINA THAT HELPED PRODUCE SOME OROGRAPHIC
CIRRUS TOWARD THE TRIAD AND MID-LEVEL CLOUDINESS TOWARD THE NORTHERN
COASTAL PLAIN. THE RAP PLAN VIEW LAYER MOISTURE PRODUCTS SEEMED TO
BE DEPICTING THE TREND OF THESE CLOUDS FAIRLY WELL. AS THE MID-LEVEL
WAVE PASSES THROUGH AS IT IS CURRENTLY...AND AS FORECAST BY THE
RAP...THE HIGH-LEVEL CLOUDS TOWARD THE TRIAD SHOULD GRADUALLY WANE.
AN INCREASE IN MID-LEVEL CLOUDINESS TOWARD THE NORTHEAST PIEDMONT
AND THE NORTHERN COASTAL PLAIN WILL ALSO WANE AS THE CLOUDS MOVE
SOUTHEAST ALONG THE THE WAVE. AREA UPPER-AIR SOUNDINGS THAT SHOW
WINDS OFF OF THE SURFACE TO AROUND 25KT...AND FORECAST 925MB WINDS
TO 20KT ALONG WITH 850MB TO 30KT SHOULD ALLOW FOR SOME GUSTINESS OF
THE WINDS WITH MIXING...WITH RAP SOUNDINGS GENERALLY SUPPORTIVE OF
GUSTS IN THE TEENS KNOTS WITH MIXING. MORNING AND FORECAST
THICKNESSES WOULD SUGGEST HIGHS NEARER THE HIGHER MAV MOS
GUIDANCE...AND WILL WATCH TRENDS DURING THE MORNING AND POSSIBLY
RAISE MAXES A DEGREE OR TWO FOR THE PLANNED LATE-MORNING UPDATE. -DJF
BY TONIGHT WE SHOULD SEE ANOTHER ROUND OF HIGH THIN CLOUDS...THIS
TIME RESULTING FROM ADVECTION OF MOISTURE CURRENTLY OVER ONTARIO.
BUT AGAIN... ALL INDICATIONS ARE THAT THESE HIGH CLOUDS WILL BE THIN
AND LARGELY CONFINED TO THE NORTHERN HALF OF NC WITH DIFFLUENT FLOW
AND SUBSIDENCE PERSISTING ALOFT. WITH WINDS GOING CALM (OR NEARLY
SO) WITH GOOD DECOUPLING AND SCANT CLOUDINESS... WILL GO A BIT BELOW
STATISTICAL GUIDANCE FOR LOWS... 27-31.
FOR SAT/SAT NIGHT: MORE OF THE SAME. THE SURFACE HIGH OVER WRN KY/TN
WILL CONTINUE TO PUSH SLOWLY EAST... BANKING UP AGAINST THE WEST
SLOPES OF THE SRN APPALACHIANS THROUGH SAT NIGHT... AND WITH THE
SURFACE LOW OVER THE NORTHEAST HAVING DRIFTED FURTHER EAST AND
OFFSHORE... THE MSLP GRADIENT WILL STEADILY SLACKEN. AGAIN EXPECT
NOTHING MORE THAN PASSING HIGH THIN CLOUDS ON SAT. THE MIXED LAYER
GETS EVEN SHALLOWER WITH ONGOING SINKING OF THE VERY WARM LAYER JUST
OFF THE SURFACE... AND THE THERMAL PROFILE SUPPORTS SLIGHTLY ABOVE
NORMAL HIGHS OF 53-59. HAVE STAYED JUST UNDER GUIDANCE FOR LOWS ONCE
AGAIN WITH EXPECTATIONS OF GOOD RADIATIONAL COOLING. LOWS SAT NIGHT
28-33. -GIH
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 230 AM FRIDAY...
A DEEP HIGH AMPLITUDE RIDGE WILL BUILD OVER THE EASTERN CONUS
INCLUDING CENTRAL NC ON SUNDAY AND THEN MOVE EAST OF THE AREA ON
MONDAY. NORMALLY THIS PATTERN WOULD SIGNAL A WARMING TREND BUT CLEAR
SKIES ON SUNDAY WILL BE REPLACED WITH SOME UPPER LEVEL CLOUDINESS ON
MONDAY AND MAX TEMPS WILL ACTUALLY FALL A FEW DEGREES ON MONDAY
ALTHOUGH NOT MUCH. EXPECT MAX TEMPS BOTH DAYS IN THE MID TO UPPER
50S TO NEAR 60 DEGREES WITH MONDAY SLIGHTLY COOLER THAN SUNDAY. LOWS
WILL MODERATE FROM NEAR FREEZING ON MONDAY MORNING TO THE MIDDLE 30S
BY TUESDAY MORNING.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 230 AM FRIDAY...
SLOWER TIMING IN THE MODELS WITH REGARD TO THE LOW AND ASSOCIATED
COLD FRONT MOVING FROM THE WEST THE MIDDLE OF NEXT WEEK. THE SYSTEM
ALREADY HAD BAD DYNAMICS WITH IT AND NOW DIURNAL TIMING DOES NOT
LOOK VERY FAVORABLE AS IT IS NOW PROGGED TO COME THROUGH LATE
TUESDAY NIGHT INTO WEDNESDAY. THE RESULT IS THAT BOTH MODELS ARE NOW
VERY SPARSE WITH THE PRECIPIATION WITH THE RANGE FROM NONE TO A FEW
HUNDREDTHS OF AN INCH. TEMPERATURE MODERATION IS NOT GREAT AS COLD
AIR ADVECTION IS NEARLY NON-EXISTENT AS THE 500 MB PATTERN IS VERY
ZONAL. WITH THE LATER TIMING EXPECT TEMPS ON TUESDAY TO RISE INTO
THE UPPER 50S TO LOW 60S WITH LOWS IN THE UPPER 30S.
THE FRONT IS EXPECTED TO MOVE THROUGH BY WEDNESDAY MORNING AND MOVE
OUT OF THE AREA. THIS WILL ALLOW SKY CONDITIONS TO IMPROVE AND TEMPS
TO RISE INTO THE MID 50S WITH GOOD INSOLATION WEDNESDAY AFTERNOON
AND DROP INTO THE MIDDLE 30S WEDNESDAY NIGHT. ANOTHER SURFACE HIGH
WILL BUILD IN ON THURSDAY WITH A SMALL AMPLITUDE UPPER LEVEL RIDGE
APPROACHING FROM THE WEST. THIS ACTUALLY WILL INITIATE SOME DEEPER
LAYER COLD AIR ADVECTION AND TEMPS ON THURSDAY WILL BE A FEW DEGREES
COOLER...MAINLY LOWER 50S.
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
AS OF 850 AM FRIDAY...
HIGH CONFIDENCE IN VFR CONDITIONS TODAY THROUGH TONIGHT. A STAGNANT
PATTERN PERSISTS OVER THE EASTERN HALF OF THE COUNTRY... WITH LOW
PRESSURE HOLDING OVER NRN NEW ENGLAND AND THE CANADIAN MARITIMES...
AND SURFACE HIGH PRESSURE CENTERED OVER THE CENTRAL MISS VALLEY AND
WRN OH VALLEY. LOW LEVEL FLOW FROM THE WEST AND NW WILL KEEP DRY AND
STABLE AIR OVER CENTRAL NC THROUGH THE UPCOMING WEEKEND. ANY SKY
COVER WILL BE RESTRICTED TO A FEW MID-CLOUDS AND MOSTLY HIGH THIN
CLOUDS...ALONG WITH UNRESTRICTED VSBYS.
LOOKING BEYOND 12Z SAT: VFR CONDITIONS WILL DOMINATE THROUGH AT
LEAST MONDAY... AS SURFACE HIGH PRESSURE BUILDS INTO AND OVER THE
REGION FROM THE WEST. AS THE HIGH SHIFTS OFFSHORE LATE MONDAY
THROUGH MONDAY NIGHT... A RETURN FLOW AND RISING MOISTURE WILL BRING
INCREASED CLOUD COVER TUE... ALTHOUGH CIGS SHOULD BE VFR.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...DJF/HARTFIELD
SHORT TERM...ELLIS
LONG TERM...ELLIS
AVIATION...DJF/HARTFIELD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1221 PM CST SAT DEC 13 2014
.UPDATE...
ISSUED AT 1215 PM CST SAT DEC 13 2014
MAIN CONCERN FOR EARLY AFTERNOON UPDATE WAS TO ADDRESS FOG OVER
THE JAMES RIVER VALLEY. THIS HAS BEEN RATHER RELUCTANT TO
DISSIPATE...SO HAVE EXTENDED FOG COVERAGE INTO THE AFTERNOON
HOURS. ELSEWHERE...TEMPERATURES CONTINUE TO WARM OVER THE
SOUTHWEST WHERE DICKINSON REPORTED A TEMPERATURE OF 58 THIS
HOUR...WHICH SETS ANOTHER RECORD HIGH.
UPDATE ISSUED AT 855 AM CST SAT DEC 13 2014
MAIN CHANGE FOR MORNING UPDATE WAS TO INCREASE CLOUD COVER OVER
WESTERN INTO PARTS OF CENTRAL NORTH DAKOTA AS HIGH CLOUDS CONTINUE
TO STREAM IN. OVER THE JAMES RIVER VALLEY...VISIBILITY REMAINS
AROUND OR UNDER A QUARTER-MILE WHERE DENSE FOG ADVISORY IS IN
EFFECT. EXPECT THIS TO IMPROVE LATER THIS MORNING THOUGH LOW CLOUDS
SHOULD LINGER THROUGH THE DAY.
UPDATE ISSUED AT 639 AM CST SAT DEC 13 2014
ADDED DENSE FOG ADVISORY FOR THE MORNING ACROSS THE JAMES RIVER
VALLEY WHERE VSBYS AT ONE QUARTER AND BELOW ARE FOUND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 217 AM CST SAT DEC 13 2014
MAIN HIGHLIGHTS IN THE SHORT TERM WILL BE PERSISTENT FOG AND STRATUS
REDEVELOPMENT THIS MORNING IN THE SOUTHERN JAMES RIVER VALLEY...FOLLOWED
BY THE TIMING FOR ANY EROSION IN THIS AREA LATER TODAY/TONIGHT.
FARTHER WEST...CLOUDS WILL INCREASE AS A COLD FRONT SHIFTS INTO
THIS AREA DURING THE AFTERNOON. NEAR RECORD HIGHS TODAY AT
WILLISTON AND DICKINSON WITH UPPER 40S NORTHWEST TO MID 50S
SOUTHWEST. ELSEWHERE EXPECT HIGHS IN THE 40S.
COLD AIR ADVECTION DEVELOPS TONIGHT INDICATING A CHANGE TOWARD
COLDER TEMPERATURES BEYOND THE SHORT TERM PERIOD.
LATEST FOG/STRATUS IMAGERY LOOP ALONG WITH SURFACE OBSERVATIONS
SHOWS FOG OVER THE SOUTHERN JAMES RIVER VALLEY WITH THE BEGINNINGS
OF ANOTHER AREA OF STRATUS DEVELOPING OVER DICKEY AND LAMOURE
COUNTIES. THE RAP13 AND HRRR 925MB RH CAPTURE THIS AREA WELL AND
DEPICT A GRADUAL EXPANSION INTO MCINTOSH COUNTY THROUGH MID
MORNING. THEREAFTER THE STRATUS IS FORECAST TO EXPAND INTO EASTERN
EMMONS AND INCH CLOSER TO JAMESTOWN BY LATE MORNING.
ELSEWHERE...INCREASING CLOUDS ESPECIALLY WEST...AS THE H7-H5 RIDGE
AXIS CONTINUES TO PUSH FARTHER EAST TODAY ACROSS MINNESOTA. A
SURFACE LOW AND COLD FRONT CURRENTLY OVER NORTH CENTRAL MONTANA
WILL SLIDE SOUTHEAST INTO WESTERN AND NORTH CENTRAL SOUTH DAKOTA
SATURDAY NIGHT. WINDS WILL SHIFT TO THE NORTHWEST WITH COLD AIR
ADVECTION INITIATING ACROSS THE WEST SATURDAY EVENING...AND
EXPANDING INTO CENTRAL NORTH DAKOTA SATURDAY NIGHT. TIME HEIGHT
CROSS SECTIONS PER NAM12 INDICATE ANOTHER AREA OF OF STRATUS AND
FOG WILL ACCOMPANY THE COLDER/MOIST AIR MASS LATE IN THE SHORT
TERM PERIOD.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 217 AM CST SAT DEC 13 2014
EXTENDED FORECAST HAS SOME MODEL UNCERTAINTIES ASSOCIATED WITH
THE REX BLOCK MODELS HAVE BEEN HINTING AT FOR THE PAST SEVERAL
DAYS LATER IN THE PERIOD. BUT FIRST...THE COLD FRONT IS FORECAST
TO MOVE THROUGH THE REGION SUNDAY. AS HAS BEEN THE CASE FOR THE
PAST FEW DAYS LIMITED MOISTURE WILL KEEP POPS ON THE LOW
SIDE WITH SLIGHT CHANCE TO CHANCE. BUFKIT SOUNDINGS SHOW A
PREFERENCE FOR SOME FREEZING RAIN AND BRIEF SLEET AS THE COLDER
AIR MOVES IN BENEATH WARMER AIR ALOFT. MODEL SOUNDINGS SHOW A LOW
LEVEL MOIST LAYER OF SUPER COOLED WATER WITH SOME DRY AIR ALOFT
WHICH SHOULD PRODUCE LIGHT FREEZING RAIN. OVERALL THE QPF IS
LIGHT BUT THERE COULD BE SOME SLIPPERY ROADS. AFTER SUNDAY THE
CURRENT VERSION OF THE GFS HAS THE MOST PRONOUNCED REX BLOCK OVER
THE NORTHERN PLAINS WEDNESDAY THROUGH FRIDAY WHILE THE ECMWF HAS
A MORE PROGRESSIVE FLOW. THE GFS WITH THE SOUTHERN BRANCH OF THE REX
BLOCK OVER THE REGION MID WEEK IS BY FAR THE COLDEST WITH H850
TEMPERATUTRES 12 TO 14 DEGREES COLDER THAN THAN ECMWF. SINCE
MODELS ARE QUITE DIFFERENT FOLLOWED THE SUPERBLEND WHICH SHOULD
AVERAGE OUT THESE DIFFERENCES AND PRODUCE SOMEWHAT NORMAL
TEMPERTATURES FOR THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1215 PM CST SAT DEC 13 2014
IFR TO LIFR VIS AND CIGS IN FOG CONTINUE OVER THE JAMES RIVER
VALLEY INCLUDING THE KJMS TERMINAL EARLY THIS AFTERNOON. EXPECT
VIS AND CIGS WILL IMPROVE SOME THIS AFTERNOON...THOUGH WILL STILL
REMAIN IFR. CONDITIONS WILL AGAIN DETERIORATE TONIGHT INTO SUNDAY
MORNING TO LIFR. ELSEWHERE VFR CONDITIONS WILL CONTINUE THROUGH
THIS AFTERNOON THOUGH WILL DETERIORATE TONIGHT AS A COOLER
AIRMASS WORKS INTO THE AREA...WITH CIGS REDUCING TO IFR LEVELS.
THERE MAY ALSO BE SOME LIGHT FREEZING DRIZZLE ON SUNDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...KS
LONG TERM...WAA
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
908 AM CST SAT DEC 13 2014
.UPDATE...
ISSUED AT 855 AM CST SAT DEC 13 2014
MAIN CHANGE FOR MORNING UPDATE WAS TO INCREASE CLOUD COVER OVER
WESTERN INTO PARTS OF CENTRAL NORTH DAKOTA AS HIGH CLOUDS CONTINUE
TO STREAM IN. OVER THE JAMES RIVER VALLEY...VISIBILITY REMAINS
AROUND OR UNDER A QUARTER-MILE WHERE DENSE FOG ADVISORY IS IN
EFFECT. EXPECT THIS TO IMPROVE LATER THIS MORNING THOUGH LOW CLOUDS
SHOULD LINGER THROUGH THE DAY.
UPDATE ISSUED AT 639 AM CST SAT DEC 13 2014
ADDED DENSE FOG ADVISORY FOR THE MORNING ACROSS THE JAMES RIVER
VALLEY WHERE VSBYS AT ONE QUARTER AND BELOW ARE FOUND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 217 AM CST SAT DEC 13 2014
MAIN HIGHLIGHTS IN THE SHORT TERM WILL BE PERSISTENT FOG AND STRATUS
REDEVELOPMENT THIS MORNING IN THE SOUTHERN JAMES RIVER VALLEY...FOLLOWED
BY THE TIMING FOR ANY EROSION IN THIS AREA LATER TODAY/TONIGHT.
FARTHER WEST...CLOUDS WILL INCREASE AS A COLD FRONT SHIFTS INTO
THIS AREA DURING THE AFTERNOON. NEAR RECORD HIGHS TODAY AT
WILLISTON AND DICKINSON WITH UPPER 40S NORTHWEST TO MID 50S
SOUTHWEST. ELSEWHERE EXPECT HIGHS IN THE 40S.
COLD AIR ADVECTION DEVELOPS TONIGHT INDICATING A CHANGE TOWARD
COLDER TEMPERATURES BEYOND THE SHORT TERM PERIOD.
LATEST FOG/STRATUS IMAGERY LOOP ALONG WITH SURFACE OBSERVATIONS
SHOWS FOG OVER THE SOUTHERN JAMES RIVER VALLEY WITH THE BEGINNINGS
OF ANOTHER AREA OF STRATUS DEVELOPING OVER DICKEY AND LAMOURE
COUNTIES. THE RAP13 AND HRRR 925MB RH CAPTURE THIS AREA WELL AND
DEPICT A GRADUAL EXPANSION INTO MCINTOSH COUNTY THROUGH MID
MORNING. THEREAFTER THE STRATUS IS FORECAST TO EXPAND INTO EASTERN
EMMONS AND INCH CLOSER TO JAMESTOWN BY LATE MORNING.
ELSEWHERE...INCREASING CLOUDS ESPECIALLY WEST...AS THE H7-H5 RIDGE
AXIS CONTINUES TO PUSH FARTHER EAST TODAY ACROSS MINNESOTA. A
SURFACE LOW AND COLD FRONT CURRENTLY OVER NORTH CENTRAL MONTANA
WILL SLIDE SOUTHEAST INTO WESTERN AND NORTH CENTRAL SOUTH DAKOTA
SATURDAY NIGHT. WINDS WILL SHIFT TO THE NORTHWEST WITH COLD AIR
ADVECTION INITIATING ACROSS THE WEST SATURDAY EVENING...AND
EXPANDING INTO CENTRAL NORTH DAKOTA SATURDAY NIGHT. TIME HEIGHT
CROSS SECTIONS PER NAM12 INDICATE ANOTHER AREA OF OF STRATUS AND
FOG WILL ACCOMPANY THE COLDER/MOIST AIR MASS LATE IN THE SHORT
TERM PERIOD.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 217 AM CST SAT DEC 13 2014
EXTENDED FORECAST HAS SOME MODEL UNCERTAINTIES ASSOCIATED WITH
THE REX BLOCK MODELS HAVE BEEN HINTING AT FOR THE PAST SEVERAL
DAYS LATER IN THE PERIOD. BUT FIRST...THE COLD FRONT IS FORECAST
TO MOVE THROUGH THE REGION SUNDAY. AS HAS BEEN THE CASE FOR THE
PAST FEW DAYS LIMITED MOISTURE WILL KEEP POPS ON THE LOW
SIDE WITH SLIGHT CHANCE TO CHANCE. BUFKIT SOUNDINGS SHOW A
PREFERENCE FOR SOME FREEZING RAIN AND BRIEF SLEET AS THE COLDER
AIR MOVES IN BENEATH WARMER AIR ALOFT. MODEL SOUNDINGS SHOW A LOW
LEVEL MOIST LAYER OF SUPER COOLED WATER WITH SOME DRY AIR ALOFT
WHICH SHOULD PRODUCE LIGHT FREEZING RAIN. OVERALL THE QPF IS
LIGHT BUT THERE COULD BE SOME SLIPPERY ROADS. AFTER SUNDAY THE
CURRENT VERSION OF THE GFS HAS THE MOST PRONOUNCED REX BLOCK OVER
THE NORTHERN PLAINS WEDNESDAY THROUGH FRIDAY WHILE THE ECMWF HAS
A MORE PROGRESSIVE FLOW. THE GFS WITH THE SOUTHERN BRANCH OF THE REX
BLOCK OVER THE REGION MID WEEK IS BY FAR THE COLDEST WITH H850
TEMPERATUTRES 12 TO 14 DEGREES COLDER THAN THAN ECMWF. SINCE
MODELS ARE QUITE DIFFERENT FOLLOWED THE SUPERBLEND WHICH SHOULD
AVERAGE OUT THESE DIFFERENCES AND PRODUCE SOMEWHAT NORMAL
TEMPERTATURES FOR THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 639 AM CST SAT DEC 13 2014
STRATUS AND FOG HAVE RETURNED TO KJMS WITH LIFR TO VLIFR CIGS/VSBYS.
THIS WILL CONTINUE THROUGH 16Z BEFORE LIFTING TO IFR. EXPECT IFR
CIGS THROUGH 01Z BEFORE LIFTING TO MVFR CONDITIONS. VFR CIGS/VSBYS
CAN BE EXPECTED AT THE REMAINING AERODROMES THROUGH 06Z SUNDAY. A
COLD FRONT WILL PUSH ACROSS WESTERN AND CENTRAL NORTH DAKOTA LATE
SATURDAY NIGHT RESULTING IN IFR CIGS AT KISN/KMOT/KDIK AFTER 06Z
SUNDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR NDZ037-048-
051.
&&
$$
UPDATE...JJS
SHORT TERM...KS
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
641 AM CST SAT DEC 13 2014
.UPDATE...
ISSUED AT 639 AM CST SAT DEC 13 2014
ADDED DENSE FOG ADVISORY FOR THE MORNING ACROSS THE JAMES RIVER
VALLEY WHERE VSBYS AT ONE QUARTER AND BELOW ARE FOUND.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 217 AM CST SAT DEC 13 2014
MAIN HIGHLIGHTS IN THE SHORT TERM WILL BE PERSISTENT FOG AND STRATUS
REDEVELOPMENT THIS MORNING IN THE SOUTHERN JAMES RIVER VALLEY...FOLLOWED
BY THE TIMING FOR ANY EROSION IN THIS AREA LATER TODAY/TONIGHT.
FARTHER WEST...CLOUDS WILL INCREASE AS A COLD FRONT SHIFTS INTO
THIS AREA DURING THE AFTERNOON. NEAR RECORD HIGHS TODAY AT
WILLISTON AND DICKINSON WITH UPPER 40S NORTHWEST TO MID 50S
SOUTHWEST. ELSEWHERE EXPECT HIGHS IN THE 40S.
COLD AIR ADVECTION DEVELOPS TONIGHT INDICATING A CHANGE TOWARD
COLDER TEMPERATURES BEYOND THE SHORT TERM PERIOD.
LATEST FOG/STRATUS IMAGERY LOOP ALONG WITH SURFACE OBSERVATIONS
SHOWS FOG OVER THE SOUTHERN JAMES RIVER VALLEY WITH THE BEGINNINGS
OF ANOTHER AREA OF STRATUS DEVELOPING OVER DICKEY AND LAMOURE
COUNTIES. THE RAP13 AND HRRR 925MB RH CAPTURE THIS AREA WELL AND
DEPICT A GRADUAL EXPANSION INTO MCINTOSH COUNTY THROUGH MID
MORNING. THEREAFTER THE STRATUS IS FORECAST TO EXPAND INTO EASTERN
EMMONS AND INCH CLOSER TO JAMESTOWN BY LATE MORNING.
ELSEWHERE...INCREASING CLOUDS ESPECIALLY WEST...AS THE H7-H5 RIDGE
AXIS CONTINUES TO PUSH FARTHER EAST TODAY ACROSS MINNESOTA. A
SURFACE LOW AND COLD FRONT CURRENTLY OVER NORTH CENTRAL MONTANA
WILL SLIDE SOUTHEAST INTO WESTERN AND NORTH CENTRAL SOUTH DAKOTA
SATURDAY NIGHT. WINDS WILL SHIFT TO THE NORTHWEST WITH COLD AIR
ADVECTION INITIATING ACROSS THE WEST SATURDAY EVENING...AND
EXPANDING INTO CENTRAL NORTH DAKOTA SATURDAY NIGHT. TIME HEIGHT
CROSS SECTIONS PER NAM12 INDICATE ANOTHER AREA OF OF STRATUS AND
FOG WILL ACCOMPANY THE COLDER/MOIST AIR MASS LATE IN THE SHORT
TERM PERIOD.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 217 AM CST SAT DEC 13 2014
EXTENDED FORECAST HAS SOME MODEL UNCERTAINTIES ASSOCIATED WITH
THE REX BLOCK MODELS HAVE BEEN HINTING AT FOR THE PAST SEVERAL
DAYS LATER IN THE PERIOD. BUT FIRST...THE COLD FRONT IS FORECAST
TO MOVE THROUGH THE REGION SUNDAY. AS HAS BEEN THE CASE FOR THE
PAST FEW DAYS LIMITED MOISTURE WILL KEEP POPS ON THE LOW
SIDE WITH SLIGHT CHANCE TO CHANCE. BUFKIT SOUNDINGS SHOW A
PREFERENCE FOR SOME FREEZING RAIN AND BRIEF SLEET AS THE COLDER
AIR MOVES IN BENEATH WARMER AIR ALOFT. MODEL SOUNDINGS SHOW A LOW
LEVEL MOIST LAYER OF SUPER COOLED WATER WITH SOME DRY AIR ALOFT
WHICH SHOULD PRODUCE LIGHT FREEZING RAIN. OVERALL THE QPF IS
LIGHT BUT THERE COULD BE SOME SLIPPERY ROADS. AFTER SUNDAY THE
CURRENT VERSION OF THE GFS HAS THE MOST PRONOUNCED REX BLOCK OVER
THE NORTHERN PLAINS WEDNESDAY THROUGH FRIDAY WHILE THE ECMWF HAS
A MORE PROGRESSIVE FLOW. THE GFS WITH THE SOUTHERN BRANCH OF THE REX
BLOCK OVER THE REGION MID WEEK IS BY FAR THE COLDEST WITH H850
TEMPERATUTRES 12 TO 14 DEGREES COLDER THAN THAN ECMWF. SINCE
MODELS ARE QUITE DIFFERENT FOLLOWED THE SUPERBLEND WHICH SHOULD
AVERAGE OUT THESE DIFFERENCES AND PRODUCE SOMEWHAT NORMAL
TEMPERTATURES FOR THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 639 AM CST SAT DEC 13 2014
STRATUS AND FOG HAVE RETURNED TO KJMS WITH LIFR TO VLIFR CIGS/VSBYS.
THIS WILL CONTINUE THROUGH 16Z BEFORE LIFTING TO IFR. EXPECT IFR
CIGS THROUGH 01Z BEFORE LIFTING TO MVFR CONDITIONS. VFR CIGS/VSBYS
CAN BE EXPECTED AT THE REMAINING AERODROMES THROUGH 06Z SUNDAY. A
COLD FRONT WILL PUSH ACROSS WESTERN AND CENTRAL NORTH DAKOTA LATE
SATURDAY NIGHT RESULTING IN IFR CIGS AT KISN/KMOT/KDIK AFTER 06Z
SUNDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 11 AM CST THIS MORNING FOR NDZ037-048-
051.
&&
$$
UPDATE...WAA
SHORT TERM...KS
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
308 AM CST SAT DEC 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 217 AM CST SAT DEC 13 2014
MAIN HIGHLIGHTS IN THE SHORT TERM WILL BE PERSISTENT FOG AND STRATUS
REDEVELOPMENT THIS MORNING IN THE SOUTHERN JAMES RIVER VALLEY...FOLLOWED
BY THE TIMING FOR ANY EROSION IN THIS AREA LATER TODAY/TONIGHT.
FARTHER WEST...CLOUDS WILL INCREASE AS A COLD FRONT SHIFTS INTO
THIS AREA DURING THE AFTERNOON. NEAR RECORD HIGHS TODAY AT
WILLISTON AND DICKINSON WITH UPPER 40S NORTHWEST TO MID 50S
SOUTHWEST. ELSEWHERE EXPECT HIGHS IN THE 40S.
COLD AIR ADVECTION DEVELOPS TONIGHT INDICATING A CHANGE TOWARD
COLDER TEMPERATURES BEYOND THE SHORT TERM PERIOD.
LATEST FOG/STRATUS IMAGERY LOOP ALONG WITH SURFACE OBSERVATIONS
SHOWS FOG OVER THE SOUTHERN JAMES RIVER VALLEY WITH THE BEGINNINGS
OF ANOTHER AREA OF STRATUS DEVELOPING OVER DICKEY AND LAMOURE
COUNTIES. THE RAP13 AND HRRR 925MB RH CAPTURE THIS AREA WELL AND
DEPICT A GRADUAL EXPANSION INTO MCINTOSH COUNTY THROUGH MID
MORNING. THEREAFTER THE STRATUS IS FORECAST TO EXPAND INTO EASTERN
EMMONS AND INCH CLOSER TO JAMESTOWN BY LATE MORNING.
ELSEWHERE...INCREASING CLOUDS ESPECIALLY WEST...AS THE H7-H5 RIDGE
AXIS CONTINUES TO PUSH FARTHER EAST TODAY ACROSS MINNESOTA. A
SURFACE LOW AND COLD FRONT CURRENTLY OVER NORTH CENTRAL MONTANA
WILL SLIDE SOUTHEAST INTO WESTERN AND NORTH CENTRAL SOUTH DAKOTA
SATURDAY NIGHT. WINDS WILL SHIFT TO THE NORTHWEST WITH COLD AIR
ADVECTION INITIATING ACROSS THE WEST SATURDAY EVENING...AND
EXPANDING INTO CENTRAL NORTH DAKOTA SATURDAY NIGHT. TIME HEIGHT
CROSS SECTIONS PER NAM12 INDICATE ANOTHER AREA OF OF STRATUS AND
FOG WILL ACCOMPANY THE COLDER/MOIST AIR MASS LATE IN THE SHORT
TERM PERIOD.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 217 AM CST SAT DEC 13 2014
EXTENDED FORECAST HAS SOME MODEL UNCERTAINTIES ASSOCIATED WITH
THE REX BLOCK MODELS HAVE BEEN HINTING AT FOR THE PAST SEVERAL
DAYS LATER IN THE PERIOD. BUT FIRST...THE COLD FRONT IS FORECAST
TO MOVE THROUGH THE REGION SUNDAY. AS HAS BEEN THE CASE FOR THE
PAST FEW DAYS LIMITED MOISTURE WILL KEEP POPS ON THE LOW
SIDE WITH SLIGHT CHANCE TO CHANCE. BUFKIT SOUNDINGS SHOW A
PREFERENCE FOR SOME FREEZING RAIN AND BRIEF SLEET AS THE COLDER
AIR MOVES IN BENEATH WARMER AIR ALOFT. MODEL SOUNDINGS SHOW A LOW
LEVEL MOIST LAYER OF SUPER COOLED WATER WITH SOME DRY AIR ALOFT
WHICH SHOULD PRODUCE LIGHT FREEZING RAIN. OVERALL THE QPF IS
LIGHT BUT THERE COULD BE SOME SLIPPERY ROADS. AFTER SUNDAY THE
CURRENT VERSION OF THE GFS HAS THE MOST PRONOUNCED REX BLOCK OVER
THE NORTHERN PLAINS WEDNESDAY THROUGH FRIDAY WHILE THE ECMWF HAS
A MORE PROGRESSIVE FLOW. THE GFS WITH THE SOUTHERN BRANCH OF THE REX
BLOCK OVER THE REGION MID WEEK IS BY FAR THE COLDEST WITH H850
TEMPERATUTRES 12 TO 14 DEGREES COLDER THAN THAN ECMWF. SINCE
MODELS ARE QUITE DIFFERENT FOLLOWED THE SUPERBLEND WHICH SHOULD
AVERAGE OUT THESE DIFFERENCES AND PRODUCE SOMEWHAT NORMAL
TEMPERTATURES FOR THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 217 AM CST SAT DEC 13 2014
MAIN TERMINAL WITH IMPACTS TO AVIATION CONTINUES TO BE KJMS. THE
STRATUS HAS TEMPORARILY MOVED OUT OF KJMS WITH MVFR/IFR VSBYS IN
FOG. ANOTHER AREA OF STRATUS WITH IFR CIGS WILL MOVE TOWARD KJMS BY
18Z SATURDAY AND IS EXPECTED TO LINGER THROUGH 00Z SUNDAY. THE
REMAINING TERMINALS OF KISN/KDIK/KMOT/KBIS WILL CONTINUE TO
EXPERIENCE VFR CIGS/VSBYS THROUGH THE TAF PERIOD. KBIS MAY BRIEFLY
SEE MVFR VSBYS IN PATCHY FOG PRIOR TO 12Z SATURDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KS
LONG TERM...WAA
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1228 PM CST FRI DEC 12 2014
.UPDATE...
ISSUED AT 1214 PM CST FRI DEC 12 2014
FOG HAS DISSIPATED OVER THE JAMES RIVER VALLEY...THOUGH LOW CLOUDS
REMAIN. THE CLOUDS MAY BREAK UP A BIT AROUND MID-AFTERNOON...BUT
LATEST GUIDANCE SUGGESTS THAT THEY WILL RE-DEVELOP AROUND SUNSET.
ELSEWHERE...QUIET WEATHER CONTINUES. SOUTHWEST NORTH DAKOTA STILL
ON TAP TO REACH RECORD TEMPERATURES...AS LAST HOUR DICKINSON
REACHED 52 DEGREES WHERE THE RECORD IS 54.
UPDATE ISSUED AT 835 AM CST FRI DEC 12 2014
AREAS OF FOG CONTINUE OVER THE JAMES RIVER VALLEY...WITH SOME
PATCHY FOG EXTENDING NORTHWARD TOWARDS THE TURTLE MOUNTAINS.
MORNING UPDATE WILL ADDRESS THIS AND KEEP THE MENTION OF FOG GOING
UNTIL MID-DAY. OTHERWISE...ONLY OTHER CHANGE WAS TO ADJUST CLOUD
COVER A BIT TO COMPENSATE FOR THIN HIGH CLOUDS OVER THE WEST.
UPDATE ISSUED AT 638 AM CST FRI DEC 12 2014
AREAS OF FOG PERSIST ACROSS THE JAMES RIVER VALLEY. VISIBILITIES
VARY FROM ONE HALF TO A MILE AT TIMES AND THE PERSISTENT FOG IS
PRODUCING SOME FROST ON ROADS. OTHERWISE HIGH SEMI THIN CLOUDS
COVERING THE WEST AND CENTRAL. STILL LOOKING FOR WARM POSSIBLY
RECORD BREAKING TEMPERATURES SOUTHWEST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 305 AM CST FRI DEC 12 2014
MAIN WEATHER HIGHLIGHTS IN THE SHORT TERM INCLUDE...SLICK ROADS AND
SIDEWALKS DURING THE MORNING COMMUTE DUE TO FROST FORMATION...WIDESPREAD
FOG ACROSS THE JAMES RIVER VALLEY ALTHOUGH NOT DENSE...THE TIMING
OF THE FOG/STRATUS ERODING TODAY AND ITS EFFECT ON HIGH TEMPERATURES.
ACROSS THE SOUTHWEST...NEAR RECORD HIGHS EXPECTED...VERY SIMILAR TO
THURSDAY. OVERALL THE WEATHER PATTERN REMAINS TRANQUIL IN TERMS OF
NO SIGNIFICANT WEATHER SYSTEMS OR PRECIPITATION THROUGH THE SHORT
TERM PERIOD.
A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO COVER THE FOG ALONG
WITH THE FROST AND RESULTANT SLIPPERY ROADS AND SIDEWALKS ACROSS
SOUTH CENTRAL NORTH DAKOTA DURING THE MORNING COMMUTE.
THE LATEST FOG/STRATUS LOOP IS BEING OVERSHADOWED BY SCT/BKN HIGH
CLOUDS. SURFACE OBSERVATIONS CONTINUE TO SHOW OVERCAST CONDITIONS/STRATUS
CLOUDS ALONG WITH VISIBILITIES RANGING BETWEEN ONE AND FOUR MILES
ACROSS THE JAMES RIVER VALLEY. THE LATEST HRRR CIG AND VSBY
FORECAST SHOW THIS AREA MAINLY REMAINING IN THE SOUTHERN JAMES
RIVER VALLEY THROUGH MID TO LATE MORNING...THEN SHRINKING/ERODING
THROUGH THE AFTERNOON. HIGH TEMPERATURES WILL BE DEPENDENT ON WHEN
THIS OCCURS...AND CURRENT TIMING OF PARTIAL CLEARING DURING THE
AFTERNOON WOULD YIELD HIGHS IN THE MID AND UPPER 30S ACROSS THE
JAMES RIVER VALLEY. MEANWHILE 925MB TEMPS NEARLY THE SAME TODAY AS
THURSDAY ACROSS THE WEST/SOUTHWEST WITH VERY SHALLOW MIXING AT
BEST. 24HR TEMPERATURE TRENDS AT DICKINSON AND HETTINGER THIS
MORNING ARE NEARLY THE SAME OR A BIT COOLER THAN AT THE SAME TIME
YESTERDAY. WILL TREND TEMPERATURES CLOSE TO WHAT THEY WERE
THURSDAY. DICKINSON REMAINS ON TRACK TO JUST BREAK ITS RECORD OF
54F SET BACK IN 1924...AS TODAYS HIGH IS EXPECTED TO REACH 55F.
ELSEWHERE IT WILL BE WARMER BUT NOT RECORD BREAKING. LOW CLOUDS
AND AREAS FOG MAY MAKE A RETURN IN THE FAR SOUTHERN JAMES RIVER
VALLEY AGAIN FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 305 AM CST FRI DEC 12 2014
MODELS BRING AN H500 TROUGH OVER THE WESTERN US SATURDAY INTO THE
CENTRAL SECTIONS OF THE COUNTY BY TUESDAY AND THEN EVENTUALLY
FORM A REX BLOCK BY WEDNESDAY/THURSDAY. DURING THIS PROCESS A COLD
FRONT WILL INITIALLY MOVE THROUGH THE NORTHERN PLAINS SATURDAY
NIGHT BRINGING SPOTTY LIGHT SNOW TO THE REGION SUNDAY. COOLER AIR
WILL FLOW THROUGH THE REGION SUNDAY AND MONDAY SETTING UP A
BAROCLINIC ZONE. ONE VERSION...THE CANADIAN GEM...SETS UP THE
BAROCLINIC ZONE ACROSS WESTERN SOUTH DAKOTA INTO SOUTHERN NORTH
DAKOTA. PRECIPITATION THEN FORMS ACROSS THIS AREA AS A CUTOFF
UPPER LOW SWINGS NORTHEAST INTO THE GREAT LAKES. THE GEM IS ALSO
SLOWER THAN THE GFS/ECMWF AND APPEARS TO BE THE PREFERRED
TREND. WILL SPREAD A CHANCE FOR SNOW ACROSS SOUTHERN NORTH DAKOTA
ON MONDAY. TUESDAY THROUGH THURSDAY BRINGS COOLER TEMPERATURES AS
THE FAIRLY SIGNIFICANT REX BLOCK RESULTS IN THE UPPER LOW OVER THE
REGION WITH THE HIGH TO THE NORTH. THIS WILL EVENTUALLY KEEP MORE
CLOUDS BUT LITTLE PRECIPITATION THROUGH THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1214 PM CST FRI DEC 12 2014
AREAS OF IFR CIGS WILL CONTINUE OVER THE JAMES RIVER VALLEY
INCLUDING THE KJMS TERMINAL THROUGH THIS AFTERNOON INTO TONIGHT
AND SATURDAY MORNING. ELSEWHERE...VFR CONDITIONS WILL PREVAIL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...KS
LONG TERM...WAA
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
842 AM CST FRI DEC 12 2014
.UPDATE...
ISSUED AT 835 AM CST FRI DEC 12 2014
AREAS OF FOG CONTINUE OVER THE JAMES RIVER VALLEY...WITH SOME
PATCHY FOG EXTENDING NORTHWARD TOWARDS THE TURTLE MOUNTAINS.
MORNING UPDATE WILL ADDRESS THIS AND KEEP THE MENTION OF FOG GOING
UNTIL MID-DAY. OTHERWISE...ONLY OTHER CHANGE WAS TO ADJUST CLOUD
COVER A BIT TO COMPENSATE FOR THIN HIGH CLOUDS OVER THE WEST.
UPDATE ISSUED AT 638 AM CST FRI DEC 12 2014
AREAS OF FOG PERSIST ACROSS THE JAMES RIVER VALLEY. VISIBILITIES
VARY FROM ONE HALF TO A MILE AT TIMES AND THE PERSISTENT FOG IS
PRODUCING SOME FROST ON ROADS. OTHERWISE HIGH SEMI THIN CLOUDS
COVERING THE WEST AND CENTRAL. STILL LOOKING FOR WARM POSSIBLY
RECORD BREAKING TEMPERATURES SOUTHWEST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 305 AM CST FRI DEC 12 2014
MAIN WEATHER HIGHLIGHTS IN THE SHORT TERM INCLUDE...SLICK ROADS AND
SIDEWALKS DURING THE MORNING COMMUTE DUE TO FROST FORMATION...WIDESPREAD
FOG ACROSS THE JAMES RIVER VALLEY ALTHOUGH NOT DENSE...THE TIMING
OF THE FOG/STRATUS ERODING TODAY AND ITS EFFECT ON HIGH TEMPERATURES.
ACROSS THE SOUTHWEST...NEAR RECORD HIGHS EXPECTED...VERY SIMILAR TO
THURSDAY. OVERALL THE WEATHER PATTERN REMAINS TRANQUIL IN TERMS OF
NO SIGNIFICANT WEATHER SYSTEMS OR PRECIPITATION THROUGH THE SHORT
TERM PERIOD.
A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO COVER THE FOG ALONG
WITH THE FROST AND RESULTANT SLIPPERY ROADS AND SIDEWALKS ACROSS
SOUTH CENTRAL NORTH DAKOTA DURING THE MORNING COMMUTE.
THE LATEST FOG/STRATUS LOOP IS BEING OVERSHADOWED BY SCT/BKN HIGH
CLOUDS. SURFACE OBSERVATIONS CONTINUE TO SHOW OVERCAST CONDITIONS/STRATUS
CLOUDS ALONG WITH VISIBILITIES RANGING BETWEEN ONE AND FOUR MILES
ACROSS THE JAMES RIVER VALLEY. THE LATEST HRRR CIG AND VSBY
FORECAST SHOW THIS AREA MAINLY REMAINING IN THE SOUTHERN JAMES
RIVER VALLEY THROUGH MID TO LATE MORNING...THEN SHRINKING/ERODING
THROUGH THE AFTERNOON. HIGH TEMPERATURES WILL BE DEPENDENT ON WHEN
THIS OCCURS...AND CURRENT TIMING OF PARTIAL CLEARING DURING THE
AFTERNOON WOULD YIELD HIGHS IN THE MID AND UPPER 30S ACROSS THE
JAMES RIVER VALLEY. MEANWHILE 925MB TEMPS NEARLY THE SAME TODAY AS
THURSDAY ACROSS THE WEST/SOUTHWEST WITH VERY SHALLOW MIXING AT
BEST. 24HR TEMPERATURE TRENDS AT DICKINSON AND HETTINGER THIS
MORNING ARE NEARLY THE SAME OR A BIT COOLER THAN AT THE SAME TIME
YESTERDAY. WILL TREND TEMPERATURES CLOSE TO WHAT THEY WERE
THURSDAY. DICKINSON REMAINS ON TRACK TO JUST BREAK ITS RECORD OF
54F SET BACK IN 1924...AS TODAYS HIGH IS EXPECTED TO REACH 55F.
ELSEWHERE IT WILL BE WARMER BUT NOT RECORD BREAKING. LOW CLOUDS
AND AREAS FOG MAY MAKE A RETURN IN THE FAR SOUTHERN JAMES RIVER
VALLEY AGAIN FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 305 AM CST FRI DEC 12 2014
MODELS BRING AN H500 TROUGH OVER THE WESTERN US SATURDAY INTO THE
CENTRAL SECTIONS OF THE COUNTY BY TUESDAY AND THEN EVENTUALLY
FORM A REX BLOCK BY WEDNESDAY/THURSDAY. DURING THIS PROCESS A COLD
FRONT WILL INITIALLY MOVE THROUGH THE NORTHERN PLAINS SATURDAY
NIGHT BRINGING SPOTTY LIGHT SNOW TO THE REGION SUNDAY. COOLER AIR
WILL FLOW THROUGH THE REGION SUNDAY AND MONDAY SETTING UP A
BAROCLINIC ZONE. ONE VERSION...THE CANADIAN GEM...SETS UP THE
BAROCLINIC ZONE ACROSS WESTERN SOUTH DAKOTA INTO SOUTHERN NORTH
DAKOTA. PRECIPITATION THEN FORMS ACROSS THIS AREA AS A CUTOFF
UPPER LOW SWINGS NORTHEAST INTO THE GREAT LAKES. THE GEM IS ALSO
SLOWER THAN THE GFS/ECMWF AND APPEARS TO BE THE PREFERRED
TREND. WILL SPREAD A CHANCE FOR SNOW ACROSS SOUTHERN NORTH DAKOTA
ON MONDAY. TUESDAY THROUGH THURSDAY BRINGS COOLER TEMPERATURES AS
THE FAIRLY SIGNIFICANT REX BLOCK RESULTS IN THE UPPER LOW OVER THE
REGION WITH THE HIGH TO THE NORTH. THIS WILL EVENTUALLY KEEP MORE
CLOUDS BUT LITTLE PRECIPITATION THROUGH THE REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 638 AM CST FRI DEC 12 2014
LIFR/VLIFR CIGS/VSBYS AT KJMS WILL CONTINUE THROUGH 18Z. CIGS/VSBYS
WILL MOST LIKELY RETURN TO MVFR/LOW VFR DURING THE AFTERNOON BUT MAY
ONCE AGAIN DETERIORATE BACK TO MVFR/IFR AFTER 00Z SATURDAY.
ELSEWHERE...PATCHY FOG AT KBIS MAY RESULT IN A BRIEF PERIOD OF MVFR
VSBYS BUT CIGS ARE FORECAST TO REMAIN VFR. VFR CIGS/VSBYS WITH
SCT/BKN HIGH CLOUDS ARE EXPECTED AT KISN/KDIK/KMOT THROUGH THE TAF
PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...KS
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
642 AM CST FRI DEC 12 2014
.UPDATE...
ISSUED AT 638 AM CST FRI DEC 12 2014
AREAS OF FOG PERSIST ACROSS THE JAMES RIVER VALLEY. VISIBILITIES
VARY FROM ONE HALF TO A MILE AT TIMES AND THE PERSISTENT FOG IS
PRODUCING SOME FROST ON ROADS. OTHERWISE HIGH SEMI THIN CLOUDS
COVERING THE WEST AND CENTRAL. STILL LOOKING FOR WARM POSSIBLY
RECORD BREAKING TEMPERATURES SOUTHWEST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 305 AM CST FRI DEC 12 2014
MAIN WEATHER HIGHLIGHTS IN THE SHORT TERM INCLUDE...SLICK ROADS AND
SIDEWALKS DURING THE MORNING COMMUTE DUE TO FROST FORMATION...WIDESPREAD
FOG ACROSS THE JAMES RIVER VALLEY ALTHOUGH NOT DENSE...THE TIMING
OF THE FOG/STRATUS ERODING TODAY AND ITS EFFECT ON HIGH TEMPERATURES.
ACROSS THE SOUTHWEST...NEAR RECORD HIGHS EXPECTED...VERY SIMILAR TO
THURSDAY. OVERALL THE WEATHER PATTERN REMAINS TRANQUIL IN TERMS OF
NO SIGNIFICANT WEATHER SYSTEMS OR PRECIPITATION THROUGH THE SHORT
TERM PERIOD.
A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO COVER THE FOG ALONG
WITH THE FROST AND RESULTANT SLIPPERY ROADS AND SIDEWALKS ACROSS
SOUTH CENTRAL NORTH DAKOTA DURING THE MORNING COMMUTE.
THE LATEST FOG/STRATUS LOOP IS BEING OVERSHADOWED BY SCT/BKN HIGH
CLOUDS. SURFACE OBSERVATIONS CONTINUE TO SHOW OVERCAST CONDITIONS/STRATUS
CLOUDS ALONG WITH VISIBILITIES RANGING BETWEEN ONE AND FOUR MILES
ACROSS THE JAMES RIVER VALLEY. THE LATEST HRRR CIG AND VSBY
FORECAST SHOW THIS AREA MAINLY REMAINING IN THE SOUTHERN JAMES
RIVER VALLEY THROUGH MID TO LATE MORNING...THEN SHRINKING/ERODING
THROUGH THE AFTERNOON. HIGH TEMPERATURES WILL BE DEPENDENT ON WHEN
THIS OCCURS...AND CURRENT TIMING OF PARTIAL CLEARING DURING THE
AFTERNOON WOULD YIELD HIGHS IN THE MID AND UPPER 30S ACROSS THE
JAMES RIVER VALLEY. MEANWHILE 925MB TEMPS NEARLY THE SAME TODAY AS
THURSDAY ACROSS THE WEST/SOUTHWEST WITH VERY SHALLOW MIXING AT
BEST. 24HR TEMPERATURE TRENDS AT DICKINSON AND HETTINGER THIS
MORNING ARE NEARLY THE SAME OR A BIT COOLER THAN AT THE SAME TIME
YESTERDAY. WILL TREND TEMPERATURES CLOSE TO WHAT THEY WERE
THURSDAY. DICKINSON REMAINS ON TRACK TO JUST BREAK ITS RECORD OF
54F SET BACK IN 1924...AS TODAYS HIGH IS EXPECTED TO REACH 55F.
ELSEWHERE IT WILL BE WARMER BUT NOT RECORD BREAKING. LOW CLOUDS
AND AREAS FOG MAY MAKE A RETURN IN THE FAR SOUTHERN JAMES RIVER
VALLEY AGAIN FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 305 AM CST FRI DEC 12 2014
MODELS BRING AN H500 TROUGH OVER THE WESTERN US SATURDAY INTO THE
CENTRAL SECTIONS OF THE COUNTY BY TUESDAY AND THEN EVENTUALLY
FORM A REX BLOCK BY WEDNESDAY/THURSDAY. DURING THIS PROCESS A COLD
FRONT WILL INITIALLY MOVE THROUGH THE NORTHERN PLAINS SATURDAY
NIGHT BRINGING SPOTTY LIGHT SNOW TO THE REGION SUNDAY. COOLER AIR
WILL FLOW THROUGH THE REGION SUNDAY AND MONDAY SETTING UP A
BAROCLINIC ZONE. ONE VERSION...THE CANADIAN GEM...SETS UP THE
BAROCLINIC ZONE ACROSS WESTERN SOUTH DAKOTA INTO SOUTHERN NORTH
DAKOTA. PRECIPITATION THEN FORMS ACROSS THIS AREA AS A CUTOFF
UPPER LOW SWINGS NORTHEAST INTO THE GREAT LAKES. THE GEM IS ALSO
SLOWER THAN THE GFS/ECMWF AND APPEARS TO BE THE PREFERRED
TREND. WILL SPREAD A CHANCE FOR SNOW ACROSS SOUTHERN NORTH DAKOTA
ON MONDAY. TUESDAY THROUGH THURSDAY BRINGS COOLER TEMPERATURES AS
THE FAIRLY SIGNIFICANT REX BLOCK RESULTS IN THE UPPER LOW OVER THE
REGION WITH THE HIGH TO THE NORTH. THIS WILL EVENTUALLY KEEP MORE
CLOUDS BUT LITTLE PRECIPITATION THROUGH THE REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 638 AM CST FRI DEC 12 2014
LIFR/VLIFR CIGS/VSBYS AT KJMS WILL CONTINUE THROUGH 18Z. CIGS/VSBYS
WILL MOST LIKELY RETURN TO MVFR/LOW VFR DURING THE AFTERNOON BUT MAY
ONCE AGAIN DETERIORATE BACK TO MVFR/IFR AFTER 00Z SATURDAY.
ELSEWHERE...PATCHY FOG AT KBIS MAY RESULT IN A BRIEF PERIOD OF MVFR
VSBYS BUT CIGS ARE FORECAST TO REMAIN VFR. VFR CIGS/VSBYS WITH
SCT/BKN HIGH CLOUDS ARE EXPECTED AT KISN/KDIK/KMOT THROUGH THE TAF
PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...KS
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION...CORRECTED
NWS BISMARCK ND
429 AM CST FRI DEC 12 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 305 AM CST FRI DEC 12 2014
MAIN WEATHER HIGHLIGHTS IN THE SHORT TERM INCLUDE...SLICK ROADS AND
SIDEWALKS DURING THE MORNING COMMUTE DUE TO FROST FORMATION...WIDESPREAD
FOG ACROSS THE JAMES RIVER VALLEY ALTHOUGH NOT DENSE...THE TIMING
OF THE FOG/STRATUS ERODING TODAY AND ITS EFFECT ON HIGH TEMPERATURES.
ACROSS THE SOUTHWEST...NEAR RECORD HIGHS EXPECTED...VERY SIMILAR TO
THURSDAY. OVERALL THE WEATHER PATTERN REMAINS TRANQUIL IN TERMS OF
NO SIGNIFICANT WEATHER SYSTEMS OR PRECIPITATION THROUGH THE SHORT
TERM PERIOD.
A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO COVER THE FOG ALONG
WITH THE FROST AND RESULTANT SLIPPERY ROADS AND SIDEWALKS ACROSS
SOUTH CENTRAL NORTH DAKOTA DURING THE MORNING COMMUTE.
THE LATEST FOG/STRATUS LOOP IS BEING OVERSHADOWED BY SCT/BKN HIGH
CLOUDS. SURFACE OBSERVATIONS CONTINUE TO SHOW OVERCAST CONDITIONS/STRATUS
CLOUDS ALONG WITH VISIBILITIES RANGING BETWEEN ONE AND FOUR MILES
ACROSS THE JAMES RIVER VALLEY. THE LATEST HRRR CIG AND VSBY
FORECAST SHOW THIS AREA MAINLY REMAINING IN THE SOUTHERN JAMES
RIVER VALLEY THROUGH MID TO LATE MORNING...THEN SHRINKING/ERODING
THROUGH THE AFTERNOON. HIGH TEMPERATURES WILL BE DEPENDENT ON WHEN
THIS OCCURS...AND CURRENT TIMING OF PARTIAL CLEARING DURING THE
AFTERNOON WOULD YIELD HIGHS IN THE MID AND UPPER 30S ACROSS THE
JAMES RIVER VALLEY. MEANWHILE 925MB TEMPS NEARLY THE SAME TODAY AS
THURSDAY ACROSS THE WEST/SOUTHWEST WITH VERY SHALLOW MIXING AT
BEST. 24HR TEMPERATURE TRENDS AT DICKINSON AND HETTINGER THIS
MORNING ARE NEARLY THE SAME OR A BIT COOLER THAN AT THE SAME TIME
YESTERDAY. WILL TREND TEMPERATURES CLOSE TO WHAT THEY WERE
THURSDAY. DICKINSON REMAINS ON TRACK TO JUST BREAK ITS RECORD OF
54F SET BACK IN 1924...AS TODAYS HIGH IS EXPECTED TO REACH 55F.
ELSEWHERE IT WILL BE WARMER BUT NOT RECORD BREAKING. LOW CLOUDS
AND AREAS FOG MAY MAKE A RETURN IN THE FAR SOUTHERN JAMES RIVER
VALLEY AGAIN FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 305 AM CST FRI DEC 12 2014
MODELS BRING AN H500 TROUGH OVER THE WESTERN US SATURDAY INTO THE
CENTRAL SECTIONS OF THE COUNTY BY TUESDAY AND THEN EVENTUALLY
FORM A REX BLOCK BY WEDNESDAY/THURSDAY. DURING THIS PROCESS A COLD
FRONT WILL INITIALLY MOVE THROUGH THE NORTHERN PLAINS SATURDAY
NIGHT BRINGING SPOTTY LIGHT SNOW TO THE REGION SUNDAY. COOLER AIR
WILL FLOW THROUGH THE REGION SUNDAY AND MONDAY SETTING UP A
BAROCLINIC ZONE. ONE VERSION...THE CANADIAN GEM...SETS UP THE
BAROCLINIC ZONE ACROSS WESTERN SOUTH DAKOTA INTO SOUTHERN NORTH
DAKOTA. PRECIPITATION THEN FORMS ACROSS THIS AREA AS A CUTOFF
UPPER LOW SWINGS NORTHEAST INTO THE GREAT LAKES. THE GEM IS ALSO
SLOWER THAN THE GFS/ECMWF AND APPEARS TO BE THE PREFERRED
TREND. WILL SPREAD A CHANCE FOR SNOW ACROSS SOUTHERN NORTH DAKOTA
ON MONDAY. TUESDAY THROUGH THURSDAY BRINGS COOLER TEMPERATURES AS
THE FAIRLY SIGNIFICANT REX BLOCK RESULTS IN THE UPPER LOW OVER THE
REGION WITH THE HIGH TO THE NORTH. THIS WILL EVENTUALLY KEEP MORE
CLOUDS BUT LITTLE PRECIPITATION THROUGH THE REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 305 AM CST FRI DEC 12 2014
IFR CIGS AT KJMS ALONG WITH MVFR/IFR VSBYS IN FOG WILL CONTINUE
THROUGH 18Z. CIGS WILL MOST LIKELY RETURN TO MVFR/LOW VFR BY MID
AFTERNOON BUT MAY ONCE AGAIN DETERIORATE BACK TO MVFR/IFR AFTER
00Z SATURDAY. ELSEWHERE...PATCHY FOG AT KBIS MAY RESULT IN A BRIEF
PERIOD OF MVFR VSBYS BUT CIGS ARE FORECAST TO REMAIN VFR. VFR
CIGS/VSBYS WITH SCT/BKN HIGH CLOUDS ARE EXPECTED AT KISN/KDIK/KMOT
THROUGH THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KS
LONG TERM...WAA
AVIATION...KS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1252 AM EST SAT DEC 13 2014
.SYNOPSIS...
LOW CLOUDS TONIGHT THROUGH SUNDAY...POSSIBLY WITH DRIZZLE OR
FREEZING DRIZZLE AT NIGHT. LOW PRESSURE SYSTEM BRINGS RAIN AND
WINTRY MIX WEDNESDAY AND THURSDAY.
&&
.NEAR TERM /THROUGH TODAY/...
1030 PM UPDATE...
AFTER COORDINATING WITH PBZ...ELECTED TO HOIST THE SPS FOR PATCHY
FZDZ AND FZFG LATE TONIGHT FROM KANAWHA VALLEY INTO THE N WV
LOWLANDS AND W SLOPES OF N MOUNTAINS. THINKING FZFG AND/OR MIST
WOULD BE MORE PREDOMINATE THOUGH...EXCEPT E OF I79 CORRIDOR TO W
SLOPES WHERE MORE OROGRAPHIC LIFT COULD RESULT IN DZ. EKN TOUGH
CALL...AS MOISTURE MAY BE TOO SHALLOW TO MAKE IT OVER THE RIDGE
LINE. NOT MUCH LIFT IN VERY SHALLOW MOIST LYR OVER TOWARD HTS AND
BKW FOR FG.
700 PM UPDATE...
BIG CHANGES ON THE WAY. UNUSUAL PATTERN FOR THIS REGION WILL BEGIN
OVERNIGHT AND LAST THRU THE WEEKEND.
VERY LOW STRATUS MARCHING STEADILY E ACROSS THE OH VALLEY THIS
EVENING WITH SOME FG AND FZ FG NOTED ON A FEW OBS. THIS IS IN RESPONSE
TO SHALLOW MOISTURE ADVECTION ON LOW LEVEL CAA BENEATH A RATHER
STRONG SUBSIDENCE INVERSION. LOOKING AROUND H9 FOR MAX VERTICAL
EXTENT OF THIS MOISTURE. GENERALLY GOOD AGREEMENT ON THE TIMING OF
THE STRATUS INTO THE AREA OVERNIGHT. GFS AND THUS LAMP GUIDANCE
USELESS IN THIS SETUP. HAVE TO STAY WITH NEAR TERM HI RES MODELS.
DID JUST THAT...INCORPORATING MOSTLY HRRR FOR EVENING UPDATE.
THIS RESULTS IN GOING OVC IN SKY GRIDS USING HRRR TIMING OF
STRATUS LATER TONIGHT. GIVEN THE AMOUNT OF MOISTURE NEAR THE
SURFACE AND UPSTREAM OBS OF LOW VSBY IN FG...FELT OBLIGATED TO
ROLL WITH LOW VSBY TOWARD MORNING AS HRRR INDICATES. THIS COMBINED
WITH SUB FREEZING TEMPS MOST AREAS...YIELDS A CONCERN FOR FZ FG.
THERE IS ENOUGH LIFT UP AGAINST THE MOUNTAINS FOR A FZ DZ WORRY
CRW TO CKB PREDAWN. WILL CONTINUE TO MONITOR TO SEE IF AN SPS IS
WARRANTED FOR THIS. VERY TRICKY TO SAY THE LEAST GIVEN THIS
UNUSUAL SETUP.
ALLOWED VSBY TO IMPROVE BY MID MORNING WITH A GRADUAL LIFTING OF
BASES...BUT STILL CARRYING OVC LOW STRATUS ALL DAY. THINK ANY DZ
OR FZ DZ SHOULD SUBSIDE BY MID MORNING ACROSS THE N. GIVEN THE
VERY SHALLOW NATURE TO THE MOISTURE...TRIED TO KEEP ELEVATIONS ABV
3500 FT OUT OF THE STRATUS DECK. WILL BE INTERESTING TO SEE IF
THIS VERIFIES. ELECTED TO KNOCK TEMPS DOWN FOR TOMORROW...MORE IN
LINE WITH MET GUIDANCE AND LOCAL IN HOUSE MOS.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY/...
A HIGH PRESSURE SYSTEM WILL SLOWLY MOVE OVER THE REGION THROUGH THE
PERIOD. A QUICK LOOK AT THE 850 MB WARMING TEMPERATURES AND LACK OF
MOISTURE IS VERY DECEIVING. A LOW LEVEL NORTHWEST WIND FLOW KEEPS A
STRONG LOW LEVEL INVERSION WITH MUCH COOLER AIR IN THE BOUNDARY
LAYER. MOISTURE IS SUFFICIENT FOR A LOW CLOUD DECK. BIG QUESTION IS
WHETHER THE MOISTURE WILL BE DEEP ENOUGH TO PRODUCE ANY DRIZZLE. MET
MOS POPS SATURDAY NIGHT INTO SUNDAY ARE RATHER SOBERING IN THE
NORTHERN MOUNTAIN AREA...SO WILL MAINTAIN A CHANCE FOR
DRIZZLE/FREEZING DRIZZLE.
CLOUDS BEGIN TO BREAK UP ON MONDAY...ALLOWING FOR TEMPERATURES TO
MODERATE.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER TROF SLIDES PAST AREA ON TUESDAY BRINGING A THREAT FOR LIGHT
PRECIPITATION THEN QUICKLY MOVES OFF TO THE NORTHEAST.
WED THRU FRI MORNING LOOK GENERALLY DRY. MODELS ALL IN GOOD
AGREEMENT THROUGH THIS POINT.
ON FRIDAY AFTERNOON...MODELS BEGIN TO DIVERGE GREATLY WITH GFS
KEEPING A BAROCLINIC ZONE OVER AREA WITH PERIODS OF PRECIPITATION
IN A WARM SECTOR SET-UP WHILE EURO COMPLETELY OMITS THIS
FEATURE. DID NOT GO COMPLETELY GFS...BUT DID NOT DISCOUNT IT
EITHER. BLENDED ABOUT 30 PERCENT TOWARDS GFS PRECIP FIELDS. THE
GOOD NEWS IS BOTH MODELS EVENTUALLY FORM AN ORGANIZED LOW BRINGING
PLENTY OF PRECIPITATION AND WIND TO THE AREA ON SATURDAY. THE
BACKSIDE OF THIS LOOKS COOL ENOUGH TO BE SNOW...BUT LIKE USUAL
MOST OF THE MOISTURE SHOULD HAVE FALLEN AS RAIN. THIS SYSTEM MOVES OUT
OF THE AREA ON SUNDAY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
06Z SATURDAY THRU 06Z SUNDAY...
IFR STRATUS MARCHING E THRU THE OH VALLEY AMID SOME LOW VSBY IN FG
AND FZFG. THESE CONDITIONS WILL OVERSPREAD THE AREA FROM NW TO SE
06Z TO 12Z WITH PLACES LIKE EKN AND BKW HOLDING OUT UNTIL PERHAPS
12Z. HAVE CIGS LOWERING THRU LIFR/VLIFR DURING THE PREDAWN FOR
CRW/PKB/CKB...WITH SOME PATCHY FZDZ AND/OR FZ FG AND MIST. GREATEST
CHANCE FOR FZDZ 11Z TO 15Z APPEARS TO BE PKB CKB CRW AND EKN.
ELSEWHERE DURING THE PREDAWN...HELD CIGS IN IFR/LIFR RANGE AND ALLOWED
SOME VSBY RESTRICTIONS FOR KHTS AND BKW. AFTER 15Z...VSBY AND CIGS
SLOWLY IMPROVE TO MVFR BY 19Z.
AFTER 00Z SUNDAY CIGS AND VSBY AGAIN LOWERING TO IFR/LIFR BY 06Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SUNDAY...
FORECAST CONFIDENCE: LOW.
ALTERNATE SCENARIOS: WHILE IFR/LIFR CIGS/VSBY WILL BE WIDESPREAD 09Z
TO 13Z THIS MORNING...PROSPECTS FOR AND EXTENT OF FZDZ MAY VARY
CONSIDERABLY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 12/13/14
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY H H H M L L L L L L L M
HTS CONSISTENCY H L L M L L M M L L L M
BKW CONSISTENCY H H H H H H H H H M M M
EKN CONSISTENCY H H H H H H H M M L L L
PKB CONSISTENCY H L L M L L H H L L M H
CKB CONSISTENCY H H H H H L L L L L H H
AFTER 06Z SUNDAY...
IFR POSSIBLE IN LOW CLOUDS IN THE MOUNTAINS SATURDAY AND SUNDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JMV/26
NEAR TERM...ARJ/30
SHORT TERM...RPY
LONG TERM...JW
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1043 PM EST FRI DEC 12 2014
.SYNOPSIS...
LOW CLOUDS TONIGHT THROUGH SUNDAY...POSSIBLY WITH DRIZZLE OR
FREEZING DRIZZLE AT NIGHT. LOW PRESSURE SYSTEM BRINGS RAIN AND
WINTRY MIX WEDNESDAY AND THURSDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
1030 PM UPDATE...
AFTER COORDINATING WITH PBZ...ELECTED TO HOIST THE SPS FOR PATCHY
FZDZ AND FZFG LATE TONIGHT FROM KANAWHA VALLEY INTO THE N WV
LOWLANDS AND W SLOPES OF N MOUNTAINS. THINKING FZFG AND/OR MIST
WOULD BE MORE PREDOMINATE THOUGH...EXCEPT E OF I79 CORRIDOR TO W
SLOPES WHERE MORE OROGRAPHIC LIFT COULD RESULT IN DZ. EKN TOUGH
CALL...AS MOISTURE MAY BE TOO SHALLOW TO MAKE IT OVER THE RIDGE
LINE. NOT MUCH LIFT IN VERY SHALLOW MOIST LYR OVER TOWARD HTS AND
BKW FOR FG.
700 PM UPDATE...
BIG CHANGES ON THE WAY. UNUSUAL PATTERN FOR THIS REGION WILL BEGIN
OVERNIGHT AND LAST THRU THE WEEKEND.
VERY LOW STRATUS MARCHING STEADILY E ACROSS THE OH VALLEY THIS
EVENING WITH SOME FG AND FZ FG NOTED ON A FEW OBS. THIS IS IN RESPONSE
TO SHALLOW MOISTURE ADVECTION ON LOW LEVEL CAA BENEATH A RATHER
STRONG SUBSIDENCE INVERSION. LOOKING AROUND H9 FOR MAX VERTICAL
EXTENT OF THIS MOISTURE. GENERALLY GOOD AGREEMENT ON THE TIMING OF
THE STRATUS INTO THE AREA OVERNIGHT. GFS AND THUS LAMP GUIDANCE
USELESS IN THIS SETUP. HAVE TO STAY WITH NEAR TERM HI RES MODELS.
DID JUST THAT...INCORPORATING MOSTLY HRRR FOR EVENING UPDATE.
THIS RESULTS IN GOING OVC IN SKY GRIDS USING HRRR TIMING OF
STRATUS LATER TONIGHT. GIVEN THE AMOUNT OF MOISTURE NEAR THE
SURFACE AND UPSTREAM OBS OF LOW VSBY IN FG...FELT OBLIGATED TO
ROLL WITH LOW VSBY TOWARD MORNING AS HRRR INDICATES. THIS COMBINED
WITH SUB FREEZING TEMPS MOST AREAS...YIELDS A CONCERN FOR FZ FG.
THERE IS ENOUGH LIFT UP AGAINST THE MOUNTAINS FOR A FZ DZ WORRY
CRW TO CKB PREDAWN. WILL CONTINUE TO MONITOR TO SEE IF AN SPS IS
WARRANTED FOR THIS. VERY TRICKY TO SAY THE LEAST GIVEN THIS
UNUSUAL SETUP.
ALLOWED VSBY TO IMPROVE BY MID MORNING WITH A GRADUAL LIFTING OF
BASES...BUT STILL CARRYING OVC LOW STRATUS ALL DAY. THINK ANY DZ
OR FZ DZ SHOULD SUBSIDE BY MID MORNING ACROSS THE N. GIVEN THE
VERY SHALLOW NATURE TO THE MOISTURE...TRIED TO KEEP ELEVATIONS ABV
3500 FT OUT OF THE STRATUS DECK. WILL BE INTERESTING TO SEE IF
THIS VERIFIES. ELECTED TO KNOCK TEMPS DOWN FOR TOMORROW...MORE IN
LINE WITH MET GUIDANCE AND LOCAL IN HOUSE MOS.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
A HIGH PRESSURE SYSTEM WILL SLOWLY MOVE OVER THE REGION THROUGH THE
PERIOD. A QUICK LOOK AT THE 850 MB WARMING TEMPERATURES AND LACK OF
MOISTURE IS VERY DECEIVING. A LOW LEVEL NORTHWEST WIND FLOW KEEPS A
STRONG LOW LEVEL INVERSION WITH MUCH COOLER AIR IN THE BOUNDARY
LAYER. MOISTURE IS SUFFICIENT FOR A LOW CLOUD DECK. BIG QUESTION IS
WHETHER THE MOISTURE WILL BE DEEP ENOUGH TO PRODUCE ANY DRIZZLE. MET
MOS POPS SATURDAY NIGHT INTO SUNDAY ARE RATHER SOBERING IN THE
NORTHERN MOUNTAIN AREA...SO WILL MAINTAIN A CHANCE FOR
DRIZZLE/FREEZING DRIZZLE.
CLOUDS BEGIN TO BREAK UP ON MONDAY...ALLOWING FOR TEMPERATURES TO
MODERATE.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER TROF SLIDES PAST AREA ON TUESDAY BRINGING A THREAT FOR LIGHT
PRECIPITATION THEN QUICKLY MOVES OFF TO THE NORTHEAST.
WED THRU FRI MORNING LOOK GENERALLY DRY. MODELS ALL IN GOOD
AGREEMENT THROUGH THIS POINT.
ON FRIDAY AFTERNOON...MODELS BEGIN TO DIVERGE GREATLY WITH GFS
KEEPING A BAROCLINIC ZONE OVER AREA WITH PERIODS OF PRECIPITATION
IN A WARM SECTOR SET-UP WHILE EURO COMPLETELY OMITS THIS
FEATURE. DID NOT GO COMPLETELY GFS...BUT DID NOT DISCOUNT IT
EITHER. BLENDED ABOUT 30 PERCENT TOWARDS GFS PRECIP FIELDS. THE
GOOD NEWS IS BOTH MODELS EVENTUALLY FORM AN ORGANIZED LOW BRINGING
PLENTY OF PRECIPITATION AND WIND TO THE AREA ON SATURDAY. THE
BACKSIDE OF THIS LOOKS COOL ENOUGH TO BE SNOW...BUT LIKE USUAL
MOST OF THE MOISTURE SHOULD HAVE FALLEN AS RAIN. THIS SYSTEM MOVES OUT
OF THE AREA ON SUNDAY.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
COMPLICATED AND UNUSUAL SYNOPTIC SETUP IN TAF PERIOD. IFR AND MVFR
STRATUS MARCHING E THRU THE OH VALLEY THIS EVENING AMID SOME LOW
VSBY IN FG AND FZ FG. THESE CONDITIONS WILL OVERSPREAD THE AREA
FROM NW TO SE OVERNIGHT WITH PLACES LIKE EKN AND BKW HOLDING OUT
UNTIL PERHAPS 12Z. HAVE CIGS LOWERING THRU IFR AND VLIFR DURING
THE PREDAWN FOR CRW/PKB/CKB WITH SOME PATCHY FZ DZ AND/OR FZ FG
AND MIST. GREATEST CHANCE OF THIS APPEARS TO BE FOR KCKB.
ELSEWHERE...HELD CIGS IN IFR BUT ALLOWED SOME VSBY RESTRICTIONS
/MVFR/ FOR KHTS. VSBY SHOULD IMPROVE BY MID MORNING WITH ANY MIST
OR FZ FG LIFTING...HOPEFULLY. ALLOWED CIGS TO LIFT 1000 TO 1500
FEET BY LATE MORNING AND HOLD THERE REMAINDER OF TAF PERIOD.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SUNDAY...
FORECAST CONFIDENCE: LOW TONIGHT.
ALTERNATE SCENARIOS: FORECAST IFR OR WORSE CEILINGS REFORMING AFTER
AND OBSTRUCTION TO VISION DUE TO FG OR FZ FG MAY VARY CONSIDERABLY
LATE TONIGHT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 12/13/14
UTC 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
EST 1HRLY 21 22 23 00 01 02 03 04 05 06 07 08
CRW CONSISTENCY H H H H H H H M L L L L
HTS CONSISTENCY H H H H H L L L L L L L
BKW CONSISTENCY H H H H H H H H H L L L
EKN CONSISTENCY H H H H H H H H H L L M
PKB CONSISTENCY H H H H H L L M L L L L
CKB CONSISTENCY H H H H H H H H H M L L
AFTER 06Z SUNDAY...
IFR POSSIBLE IN LOW CLOUDS IN THE MOUNTAINS SATURDAY AND SUNDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JMV/26
NEAR TERM...ARJ/30
SHORT TERM...RPY
LONG TERM...JW
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
722 PM EST FRI DEC 12 2014
.SYNOPSIS...
LOW CLOUDS TONIGHT THROUGH SUNDAY...POSSIBLY WITH DRIZZLE OR
FREEZING DRIZZLE AT NIGHT. LOW PRESSURE SYSTEM BRINGS RAIN AND
WINTRY MIX WEDNESDAY AND THURSDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
700 PM UPDATE...
BIG CHANGES ON THE WAY. UNUSUAL PATTERN FOR THIS REGION WILL BEGIN
OVERNIGHT AND LAST THRU THE WEEKEND.
VERY LOW STRATUS MARCHING STEADILY E ACROSS THE OH VALLEY THIS
EVENING WITH SOME FG AND FZ FG NOTED ON A FEW OBS. THIS IS IN RESPONSE
TO SHALLOW MOISTURE ADVECTION ON LOW LEVEL CAA BENEATH A RATHER
STRONG SUBSIDENCE INVERSION. LOOKING AROUND H9 FOR MAX VERTICAL
EXTENT OF THIS MOISTURE. GENERALLY GOOD AGREEMENT ON THE TIMING OF
THE STRATUS INTO THE AREA OVERNIGHT. GFS AND THUS LAMP GUIDANCE
USELESS IN THIS SETUP. HAVE TO STAY WITH NEAR TERM HI RES MODELS.
DID JUST THAT...INCORPORATING MOSTLY HRRR FOR EVENING UPDATE.
THIS RESULTS IN GOING OVC IN SKY GRIDS USING HRRR TIMING OF
STRATUS LATER TONIGHT. GIVEN THE AMOUNT OF MOISTURE NEAR THE
SURFACE AND UPSTREAM OBS OF LOW VSBY IN FG...FELT OBLIGATED TO
ROLL WITH LOW VSBY TOWARD MORNING AS HRRR INDICATES. THIS COMBINED
WITH SUB FREEZING TEMPS MOST AREAS...YIELDS A CONCERN FOR FZ FG.
THERE IS ENOUGH LIFT UP AGAINST THE MOUNTAINS FOR A FZ DZ WORRY
CRW TO CKB PREDAWN. WILL CONTINUE TO MONITOR TO SEE IF AN SPS IS
WARRANTED FOR THIS. VERY TRICKY TO SAY THE LEAST GIVEN THIS
UNUSUAL SETUP.
ALLOWED VSBY TO IMPROVE BY MID MORNING WITH A GRADUAL LIFTING OF
BASES...BUT STILL CARRYING OVC LOW STRATUS ALL DAY. THINK ANY DZ
OR FZ DZ SHOULD SUBSIDE BY MID MORNING ACROSS THE N. GIVEN THE
VERY SHALLOW NATURE TO THE MOISTURE...TRIED TO KEEP ELEVATIONS ABV
3500 FT OUT OF THE STRATUS DECK. WILL BE INTERESTING TO SEE IF
THIS VERIFIES. ELECTED TO KNOCK TEMPS DOWN FOR TOMORROW...MORE IN
LINE WITH MET GUIDANCE AND LOCAL IN HOUSE MOS.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
A HIGH PRESSURE SYSTEM WILL SLOWLY MOVE OVER THE REGION THROUGH THE
PERIOD. A QUICK LOOK AT THE 850 MB WARMING TEMPERATURES AND LACK OF
MOISTURE IS VERY DECEIVING. A LOW LEVEL NORTHWEST WIND FLOW KEEPS A
STRONG LOW LEVEL INVERSION WITH MUCH COOLER AIR IN THE BOUNDARY
LAYER. MOISTURE IS SUFFICIENT FOR A LOW CLOUD DECK. BIG QUESTION IS
WHETHER THE MOISTURE WILL BE DEEP ENOUGH TO PRODUCE ANY DRIZZLE. MET
MOS POPS SATURDAY NIGHT INTO SUNDAY ARE RATHER SOBERING IN THE
NORTHERN MOUNTAIN AREA...SO WILL MAINTAIN A CHANCE FOR
DRIZZLE/FREEZING DRIZZLE.
CLOUDS BEGIN TO BREAK UP ON MONDAY...ALLOWING FOR TEMPERATURES TO
MODERATE.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER TROF SLIDES PAST AREA ON TUESDAY BRINGING A THREAT FOR LIGHT
PRECIPITATION THEN QUICKLY MOVES OFF TO THE NORTHEAST.
WED THRU FRI MORNING LOOK GENERALLY DRY. MODELS ALL IN GOOD
AGREEMENT THROUGH THIS POINT.
ON FRIDAY AFTERNOON...MODELS BEGIN TO DIVERGE GREATLY WITH GFS
KEEPING A BAROCLINIC ZONE OVER AREA WITH PERIODS OF PRECIPITATION
IN A WARM SECTOR SET-UP WHILE EURO COMPLETELY OMITS THIS
FEATURE. DID NOT GO COMPLETELY GFS...BUT DID NOT DISCOUNT IT
EITHER. BLENDED ABOUT 30 PERCENT TOWARDS GFS PRECIP FIELDS. THE
GOOD NEWS IS BOTH MODELS EVENTUALLY FORM AN ORGANIZED LOW BRINGING
PLENTY OF PRECIPITATION AND WIND TO THE AREA ON SATURDAY. THE
BACKSIDE OF THIS LOOKS COOL ENOUGH TO BE SNOW...BUT LIKE USUAL
MOST OF THE MOISTURE SHOULD HAVE FALLEN AS RAIN. THIS SYSTEM MOVES OUT
OF THE AREA ON SUNDAY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
COMPLICATED AND UNUSUAL SYNOPTIC SETUP IN TAF PERIOD. IFR AND MVFR
STRATUS MARCHING E THRU THE OH VALLEY THIS EVENING AMID SOME LOW
VSBY IN FG AND FZ FG. THESE CONDITIONS WILL OVERSPREAD THE AREA
FROM NW TO SE OVERNIGHT WITH PLACES LIKE EKN AND BKW HOLDING OUT
UNTIL PERHAPS 12Z. HAVE CIGS LOWERING THRU IFR AND VLIFR DURING
THE PREDAWN FOR CRW/PKB/CKB WITH SOME PATCHY FZ DZ AND/OR FZ FG
AND MIST. GREATEST CHANCE OF THIS APPEARS TO BE FOR KCKB.
ELSEWHERE...HELD CIGS IN IFR BUT ALLOWED SOME VSBY RESTRICTIONS
/MVFR/ FOR KHTS. VSBY SHOULD IMPROVE BY MID MORNING WITH ANY MIST
OR FZ FG LIFTING...HOPEFULLY. ALLOWED CIGS TO LIFT 1000 TO 1500
FEET BY LATE MORNING AND HOLD THERE REMAINDER OF TAF PERIOD.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SUNDAY...
FORECAST CONFIDENCE: LOW TONIGHT.
ALTERNATE SCENARIOS: FORECAST IFR OR WORSE CEILINGS REFORMING AFTER
AND OBSTRUCTION TO VISION DUE TO FG OR FZ FG MAY VARY CONSIDERABLY
LATE TONIGHT.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EST 1HRLY 19 20 21 22 23 00 01 02 03 04 05 06
CRW CONSISTENCY H H H H H H H H H M L L
HTS CONSISTENCY H H H H H H H L L L L L
BKW CONSISTENCY H H H H H H H H H H H L
EKN CONSISTENCY H H H H H H H H H H H M
PKB CONSISTENCY H H H H H H H L L M L L
CKB CONSISTENCY H H H H H H H H H M M M
AFTER 00Z SUNDAY...
IFR POSSIBLE IN LOW CLOUDS IN THE MOUNTAINS SATURDAY AND SUNDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JMV/26
NEAR TERM...ARJ/30
SHORT TERM...RPY
LONG TERM...JW
AVIATION...30
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
645 AM EST FRI DEC 12 2014
.SYNOPSIS...
HIGH PRESSURE WILL SHIFT SLOWLY EAST ACROSS THE REGION THROUGH THE
WEEKEND...LEADING TO A GRADUAL WARM UP THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AN AREA OF STRATUS ACROSS SOUTHEAST INDIANA HAS BEEN SLOWLY
EXPANDING THIS MORNING WITH SOME SPOTTY PATCHES ALSO DEVELOPING
ACROSS PARTS OF CENTRAL OHIO OVER THE LAST COUPLE OF HOURS. THERE
ARE SOME INDICATIONS ON BOTH THE 00Z NAM AND LATEST RAP THAT THIS
MAY CONTINUE TO FILL IN AT LEAST SOMEWHAT THROUGH DAYBREAK AS IT
CONTINUES TO DRIFT SLOWLY SOUTHEAST. AS A RESULT...WILL HEDGE A BIT
AND ALLOW FOR SOME PARTLY CLOUDY SKIES FOR A PERIOD THIS MORNING
IN ASSOCIATION WITH THESE CLOUDS. OTHERWISE...HIGH PRESSURE
CURRENTLY CENTERED OVER THE MID MISSISSIPPI VALLEY WILL SHIFT
SLOWLY EAST TODAY. THE LATEST RAP IS INDICATING THAT SOME OF THE
STRATUS CURRENTLY DROPPING DOWN ACROSS LOWER MICHIGAN COULD WORK ITS
WAY DOWN INTO NORTHERN PORTIONS OF OUR FA LATER TODAY.
HOWEVER...THINK THE SOUTHWARD PROGRESSION OF THIS WILL SLOW ONCE
THE SUN COMES UP SO WILL MAINTAIN MOSTLY SUNNY TO PARTLY CLOUDY
SKIES THROUGH THIS AFTERNOON. WITH SOME SUN AND AIRMASS
MODIFICATION...EXPECT HIGHS TODAY A BIT WARMER THAN THURSDAY. WILL
TREND TEMPS CLOSER TO THE WARMER MAV GUIDANCE WITH HIGHS RANGING
FROM THE UPPER 30S FAR NORTH TO THE MID 40S FAR SOUTH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
SURFACE HIGH PRESSURE WILL CONTINUE TO SHIFT VERY SLOWLY EASTWARD
THROUGH THE WEEKEND WHILE IT SLOWLY FLATTENS OUT. THE MODELS ARE
FAIRLY AGGRESSIVE ADVECTING SOME HIGHER LOW LEVEL MOISTURE IN FROM
THE WEST AND NORTHWEST SATURDAY INTO SUNDAY. THIS MOISTURE IS
FAIRLY SHALLOW THOUGH...GENERALLY AOB 900 MB. AS IS TYPICAL..THE
NAM IS MORE PESSIMISTIC THAN THE GFS WITH THIS LOW LEVEL MOISTURE
SO SOME UNCERTAINTY EXISTS AS TO HOW FAST THE CLOUDS WILL WORK
THEIR WAY INTO OUR AREA. RIGHT NOW...THE CLOUDS ADVANCING EASTWARD
INTO WESTERN ILLINOIS ARE STILL TO THE WEST OF THE RIDGE AXIS AND
GIVEN ITS SLOW EASTWARD PROGRESSION...WOULD THINK THESE CLOUDS MAY
TAKE A WHILE TO REACH OUR FA. THAT BEING SAID...THERE ARE ALSO
SOME INDICATIONS THAT STRATUS WILL SAG DOWN FROM THE
NORTH/NORTHWEST LATER TONIGHT INTO SATURDAY AS THE HIGH BEGINS TO
FLATTEN OUT. THIS RESULTS IN A RATHER LOW CONFIDENCE CLOUD
FORECAST FOR TONIGHT INTO SATURDAY AND WILL HANDLE IT WITH A SLOW
INCREASE IN CLOUDS. CLOUD COVER WILL OBVIOUSLY HAVE AN AFFECT ON
TEMPERATURES AND WE ARE LIKELY TOO COLD TONIGHT/WARM ON SATURDAY
IF A SOLID DECK MOVES IN FASTER THAN ANTICIPATED. WILL SLOWLY BUMP
UP TO CLOUDY SKIES SATURDAY NIGHT INTO SUNDAY AS EVEN THE GFS IS
PRETTY BULLISH ON THE LOW CLOUDS BY THEN. BOTH THE NAM AND GFS
CONTINUE TO HINT AT THE POSSIBILITY OF SOME DRIZZLE SATURDAY NIGHT
INTO SUNDAY WITH SOME VERY LIGHT AND SPOTTY QPF. WILL HOLD OFF ON
MENTIONING ANYTHING IN THE FORECAST THOUGH AS THE DEPTH OF THE
SATURATED LAYER BELOW 2000 FEET REMAINS FAIRLY SHALLOW AND WE SEEM
TO BE LACKING MUCH IN THE WAY OF LOW LEVEL FORCING/VERTICAL
MOTION.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS THE NEW WEEK BEGINS...ATTENTION WILL FOCUS ON THE TROUGH
INITIALLY OVER THE WESTERN SECTIONS OF THE COUNTRY. AS A JET
STREAK AROUND THE BASE OF THE TROUGH MOVES ASHORE...EVENTUALLY A
SURFACE LOW IS FORECAST TO DEVELOP...ASSOCIATED WITH A MID-LEVEL
LOW MOVING OUT OF THE FOUR CORNERS. HOWEVER...THE TIMING AND
STRENGTH OF THIS SYSTEM REMAINS A SOURCE OF INCONSISTENCY IN THE
MODELS...WHICH IS NOT ESPECIALLY SURPRISING GIVEN THE VARIABLES
GOING INTO ITS DEVELOPMENT. THE GOOD NEWS FOR THE FORECAST IS THAT
12Z RUNS HAVE COME INTO BETTER TIMING AND PLACEMENT
AGREEMENT...WITH THE PRIMARY CONCERNS REGARDING THE STRENGTH OF
THE LOW...AND HOW QUICKLY IT DEGENERATES INTO AN OPEN WAVE. A
CONTINUED NORTHWARD TREND IN THE MODELS HAS ENDED UP WITH THE
GREATEST PRECIPITATION CHANCES APPEARING TO IMPACT THE GREAT
LAKES...WITH THE OHIO VALLEY ON THE SOUTHERN FRINGE OF THE
GREATEST MOISTURE AND FORCING. POPS HAVE BEEN KEPT IN SIMILAR
CATEGORIES (20-40 PERCENT) BUT FOCUSED A LITTLE GREATER ON THE
NORTHERN SECTIONS OF THE CWA.
DEPENDING ON THE EXACT TIMING OF THE SYSTEM...ADVECTION IN THE
VICINITY OF THE SURFACE LOW COULD KEEP TEMPERATURES FROM DROPPING
APPRECIABLY ON MONDAY NIGHT. HOWEVER...ONCE THE LOW PASSES...COLD
ADVECTION ON THE BACK SIDE WILL PROVIDE FOR A RETURN TO COOLER
CONDITIONS FOR THE MIDDLE OF THE WEEK. THIS COLD
ADVECTION...POSSIBLY GIVEN THE SLIGHT SHIFT TO THE NORTH...DOES NOT
APPEAR PARTICULARLY STRONG ON THE 12Z GFS/ECMWF RUNS. THUS...AFTER A
FEW DAYS OF ABOVE-NORMAL TEMPERATURES...THE EXPECTED CONDITIONS FOR
WEDNESDAY AND THURSDAY ONLY APPEAR TO BE SLIGHTLY BELOW NORMAL.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
LO LVL MOISTURE BAND EXTENDS FROM SE IN EWD INTO SOUTH CENTRAL OH.
IFR CLOUDS HAVE BEEN ASSOCIATED WITH THE WESTERN PORTION OF THIS
BAND AS IT MOVES TO THE ESE. THESE CLOUDS SHOULD MOVE THROUGH THE
KCVG/KLUK BY LATE MORNING AND KILN BY EARLY AFTERNOON. ANOTHER
BAND OF LO LVL MOISTURE ACRS NORTHERN OHIO IS SLOWLY PUSHING S AND
SHOULD REACH THE KCMH/KLUK AREA AROUND MID MORNING PRODUCING CIGS
IN THE LOWER END OF MVFR. THESE CLOUDS SHOULD DISSIPATE DURING THE
EARLY AFTERNOON. HIGH PRESSURE AREA LOCATED TO OUR SW THIS MORNING
SHOULD DRAFT SLOWLY EAST. THIS WILL KEEP THE WINDS LIGHT AND FROM
THE WEST. NUMERICAL GUIDANCE DISAGREE ON THE AMOUNT AND THE DEPTH
OF THE LOW LEVEL MOISTURE THAT WILL MOVE ACRS THE AREA TONIGHT.
HAVE HELD OFF INTRODUCING MVFR/IFR CIGS UNTIL CONFIDENCE IS A
LITTLE HIGHER.
OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...JGL
NEAR TERM...JGL
SHORT TERM...JGL
LONG TERM...HATZOS
AVIATION...HAYDU
AREA FORECAST DISCUSSION
NWS PORTLAND OR
831 PM PST FRI DEC 12 2014
.SYNOPSIS...A FULL LATITUDE LARGE SCALE UPPER TROUGH OVER THE AREA
WILL CONTINUE ITS SLOW EASTWARD PROGRESSION TONIGHT. THE BULK OF THE
ENERGY ASSOCIATED WITH THIS UPPER TROUGH WILL REMAIN WELL SOUTH OF
THE FORECAST AREA. AN UPPER RIDGE WILL MOVE OVER THE REGION SATURDAY
AFTERNOON AND HOLD IN PLACE INTO SUNDAY. THE EAST WIND IS EXPECTED TO
INCREASE SUNDAY AND MONDAY...ESPECIALLY THROUGH THE COLUMBIA RIVER
GORGE. THE NEXT SYSTEM APPROACHES FROM THE WEST LATE SUNDAY AND
SUNDAY NIGHT...BUT THIS SYSTEM WILL BE RATHER WEAK. ADDITIONAL
SYSTEMS IN THE MID WEEK PERIOD WILL HOLD TOGETHER BETTER FOR SOME
MORE RAIN.
&&
.SHORT TERM...TONIGHT THROUGH MONDAY...WATER VAPOR IMAGERY THIS
EVENING SHOWS A LARGE-SCALE UPPER LEVEL TROUGH MOVING ACROSS THE PAC
NW AND CALIFORNIA. IT APPEARS THE TROUGH AXIS WAS CENTERED ALONG THE
COASTLINE AS OF 04Z. A TRANSITORY UPPER RIDGE CONTINUES TO BUILD
AROUND 135W...WHICH WILL MOVE OVER THE FORECAST AREA BY SAT
AFTERNOON. KRTX DUAL-POL DOPPLER RADAR AT 0345Z SHOWED THE REMAINING
SHOWER ACTIVITY CONFINDED TO THE NORTH OREGON CASCADES AND
FOOTHILLS...WITH SOME ISOLATED STUFF INTO THE NORTH AND CENTRAL
OREGON COAST RANGE. THE 02Z HRRR RUN SHOWS THIS SHOWER ACTIVITY
HOLDING TOGETHER TIL 05Z. LOCALIZED FOG HAS ALREADY DEVELOPED IN THE
INTERIOR VALLEYS AND ALONG THE COAST. KMMV HAS BEEN DOWN TO AS LOW AS
ONE-QUARTER MILE VIS THIS EVENING.
LITTLE CHANGES MADE TO THE SHORT-TERM. THE 00Z NAM INDICATES ANOTHER
STRETCHED-OUT VORTICITY LOBE JUST BEHIND THE UPPER TROUGH AXIS. THIS
LOBE IS FORECAST TO REACH THE COAST AROUND 09Z SAT AND REACH THE
CASCADES BY 15Z. NAM ALSO INDICATES ISOLATED SHOWER ACTIVITY LATE
TONIGHT THROUGH SAT MORNING...PRIMARILY IN SW WA AND OVER THE NORTH
OREGON COAST RANGE. EXPECT ANY AFTERNOON SHOWER ACTIVITY TO FAVOR THE
CASCADES...CLOSEST TO THE DEPARTING UPPER TROUGH AND ASSOCIATED
VORTICITY LOBE. NAM THEN SHOWS STRONG NEGATIVE VORTICITY ADVECTION
REACHING THE COAST LATE SAT AFTERNOON AND ENVELOPING THE ENTIRE AREA
BY SAT EVENING FOR CLEARING. EXPECT GREATER FOG COVERAGE SAT NIGHT
THROUGH SUN MORNING DUE TO THE CLEARING SKIES. EAST LOW-LEVEL
GRADIENTS START TO STRENGTHEN THROUGH THE COLUMBIA RIVER GORGE LATE
SAT NIGHT AND SUNDAY. THE 00Z NAM INDICATES A -7 TO -8 MB KTTD-KDLS
GRADIENT BY 18Z SUN. THIS IS ENOUGH TO PRODUCE 50-60 MPH WIND GUSTS
IN THE MORE WINDIER SPOTS. THE EAST WIND SHOULD CLEAR THE FOG IN THE
PORTLAND AND VANCOUVER AREA SUNDAY AFTERNOON...BUT AREAS FARTHER
SOUTH IN THE WILLAMETTE VALLEY WILL BE SLOWER TO CLEAR. THE NEXT
SPLITTING AND STRETCHING SYSTEM COMES IN SUNDAY NIGHT AND MONDAY WITH
SOME AREAS OF LIGHT RAIN. WEISHAAR
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...MONDAY NIGHT
THROUGH FRIDAY...A NEGATIVELY TILTED...BUT STRETCHING AND WEAKENING
FRONTAL STORM SYSTEM WILL LIKELY IMPACT THE AREA MONDAY NIGHT AND
TUESDAY. PRECIPITATION CHANCES APPEAR HIGHEST TOWARDS THE COAST AND
ACROSS THE SOUTHERN ZONES WHERE UPPER LEVEL SUPPORT WILL BE GREATEST.
QPF STILL LOOKS RELATIVELY LIGHT. GIVEN OFFSHORE FLOW WILL CONTINUE
IN THIS PATTERN...GUSTY EAST WINDS WILL CONTINUE NEAR THE WEST END OF
THE COLUMBIA RIVER GORGE DURING THIS PERIOD. WILL NEED TO MONITOR
TEMPERATURES EAST OF THE CASCADES FOR ANY WINTER PRECIPITATION IN THE
CENTRAL COLUMBIA RIVER GORGE...BUT RIGHT NOW TEMPERATURES LOOK TO
REMAIN ON THE WARM SIDE OF FREEZING EAST OF THE CASCADES.
A CLOSED LOW WILL SPIN SOUTHEASTWARD INTO THE DESERT SOUTHWEST LATE
TUESDAY INTO WEDNESDAY SO POPS WERE REDUCED ACROSS NORTHERN ZONES
DURING THIS PERIOD. SHORTWAVE RIDGING MAY THEN SHIFT OVER THE AREA
BEFORE THE NEXT FRONTAL STORM SYSTEM IMPACTS LATE IN THE WEEK...BUT
CONFIDENCE IN DETAILS AND TIMING IS LOW AT THIS POINT. AS A
RESULT...POPS WERE NUDGED TOWARDS MODEL CONSENSUS...WHILE STILL
REMAINING NEAR CLIMO. /NEUMAN
&&
.AVIATION...REMAINING MID CLOUDS CONTINUE TO DECREASE WITH
BUILDING SURFACE HIGH PRES BUILDING INTO THE REGION AS UPPER LEVEL
TROUGH CONTINUES TO SLIDE EASTWARD. THIS HAS RESULTED IN SOME FOG
DEVELOPMENT ALREADY ALONG THE CENTRAL OREGON COAST...AS WELL AS
SOME PATCHY FOG DEVELOPMENT IN THE INTERIOR VALLEYS. WITH SMALL
TEMPERATURE-DEWPOINT SPREADS AND CONTINUED CLEARING...EXPECT TO
SEE MORE IFR FOG/LOW STRATUS DEVELOP OVERNIGHTS. SOME OF THE MORE
TYPICAL FOG PRONE LOCATIONS...INCLUDING KONP...KHIO...AND
KEUG...MAY SEE THIS FOG PERSIST INTO SAT AFTERNOON. ALSO EXPECT
SOME PATCHY FOG TO DEVELOP ACROSS THE REMAINING COASTAL AREAS AND
PORTIONS OF THE WILLAMETTE VALLEY...BUT THESE AREAS SHOULD SEE
IMPROVEMENT TO VFR SOONER DURING MID TO LATE MORNING.
KPDX AND APPROACHES...DECREASING MID CLOUDS THIS EVENING FOR VFR
CONDITIONS...BUT EXPECT PATCHY MVFR TO IFR FOG/LOW STRATUS TO
DEVELOP TONIGHT AFT 09Z. THIS SHOULD LIFT TO VFR BY 18Z SAT.
CULLEN
&&
.MARINE...CONDITIONS REMAIN RATHER BENIGN OVER THE WATERS THIS
EVENING WITH W-SW WINDS AT 5 TO 10 KT AS WEAK SURFACE HIGH PRES
BUILDS. SEAS REMAIN A FOOT OR TWO BELOW GUIDANCE...HAVE ELECTED TO
MAINTAIN THE SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS THROUGH 6 AM
SATURDAY AS BUOY 46029 CONTINUES TO REPORT 11 FT AND THE BUOYS
WITHIN OUR COASTAL WATERS CONTINUE TO HOVER JUST SHY OF 10 FT.
HOWEVER...EXPECT SEAS TO EASE INTO THE 8-9 FT RANGE ON SATURDAY.
WINDS AND SEAS REMAIN SHOULD REMAIN BELOW ADVISORY THRESHOLDS
SAT...BUT ANOTHER APPROACHING FRONT WILL BRING INCREASING
SOUTHERLY WINDS AGAIN ON SUN. THE CURRENT FORECAST MODELS WEAKEN
THE FRONT SIGNIFICANTLY AS IT NEARS SHORE...SO FOR NOW IT LOOKS
LIKE ONLY A SMALL CRAFT ADVISORY WIND EVENT. THERE ARE CHANCES FOR
RELATIVELY MINOR SYSTEMS NEXT WEEK...WHICH MAY BRING ADDITIONAL
SMALL CRAFT WINDS FROM TIME TO TIME. THE NEXT WELL ORGANIZED FRONT
DOES NOT SHOW UP IN THE MODELS UNTIL THE END OF NEXT WEEK.
HOWEVER...SEAS WILL LIKELY BUILD BACK ABOVE 10 FT LATER
SUNDAY...AND REMAINING IN THE LOW TO MID TEENS FOR MUCH OF THE
EARLY PART OF NEXT WEEK. CULLEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM PST SATURDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60
NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 11 AM
PST SATURDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1055 PM CST FRI DEC 12 2014
.UPDATE...REST OF TONIGHT
DOWNSLOPE WIND EVENT ONGOING WITH THE LATEST OB AT PEEVER SHOWING
SUSTAINED AT 40 MPH GUSTING TO 50 MPH. RAP 925MB WINDS STAY FAIRLY
HIGH OUT OF THE SOUTHWEST THROUGH 12Z...BASICALLY IN THE 35 TO 45
KNOT RANGE THEN DROPPING OFF TO AROUND 30 KNOTS AT 12Z. HAVE
INCREASED WINDS QUITE A BIT THROUGH THE REMAINDER OF THE NIGHT
ALONG THE COTEAU AND ON THE DOWNSLOPE SIDE. TEMPS HAVE ALSO
RESPONDED WITH SISSETON AND PEEVER SPIKING INTO THE LOW 40S. THE
OTHER STORY THROUGH THE NIGHT WILL BE TO WHAT DEGREE WE SEE AN
INCREASE IN FOG AND STRATUS. SOUNDINGS AND 950 MB RH PLOTS ALL
SHOW VERY HIGH RH THROUGH THE NIGHT INCREASING FROM THE SOUTH.
ALTHOUGH...NOT MUCH TO SHOW FOR IT CURRENTLY WITH JUST A SMALL
STRATUS PATCH BY WATERTOWN AND ANOTHER CROSSING THE NEBRASKA
BORDER INTO SD. HAVE UPDATED SKY GRIDS TO ACCOUNT FOR MOSTLY CLEAR
EARLY ON AND INCREASING CLOUDS BY SUNRISE. ALTHOUGH...THERE IS
QUITE A BIT OF UNCERTAINTY IN REGARDS TO JUST HOW MUCH AREAL
COVERAGE OF CLOUDS THERE WILL BE. WILL LIKELY BE MAKING MANY
UPDATES TO SKY COVER THROUGH SUNRISE.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
MOST OF THE AREA HAS SEEN CLOUD COVER ERODE AWAY THIS AFTERNOON.
THE REGION WILL REMAIN BETWEEN HIGH PRESSURE TO THE EAST AND LOW
PRESSURE TO THE WEST TONIGHT...WHICH WILL LIKELY RESULT IN THE LOW
CLOUDS AND AREAS OF FOG RETURNING...MAINLY TO THE EASTERN HALF OF
THE CWA. MAY NOT BE AS MUCH TIME FOR CLEARING ON SATURDAY AS MODEL
TIME SECTIONS SHOW LOW LEVEL MOISTURE DEEPENING AHEAD OF AN
APPROACHING FRONTAL BOUNDARY...MAINLY SATURDAY AFTERNOON AND
EVENING. THIS DEEPER MOISTURE WILL LIKELY KEEP ABUNDANT CLOUD
COVER OVER THE REGION THEN THROUGH THE END OF THE PERIOD. MAY SEE
SOME LIGHT RAIN SHOWERS ACROSS THE FAR EASTERN CWA SATURDAY NIGHT
AS THE FRONT MOVES THROUGH THAT AREA AND A LITTLE ENHANCED LIFT
DEVELOPS. BIGGER CONCERNS THEN COME LATER SUNDAY AND SUNDAY NIGHT
AS A LOW PRESSURE SYSTEM TRACKS SOMEWHERE ACROSS THE CENTRAL PART
OF THE COUNTRY. RIGHT NOW...THE NAM AND ECMWF KEEP ALL
PRECIPITATION SOUTH OF THE CWA...THE GFS BRINGS IT JUST TO THE
SOUTHERN CWA...AND THE GEM PLASTERS THE ENTIRE CWA WITH SNOW
SUNDAY NIGHT. DUE TO THESE SIGNIFICANT DIFFERENCES...HAVE OPTED TO
JUST STICK WITH A SCHC/CHC POP UNTIL A MORE CERTAIN SOLUTION COMES
TOGETHER.
ABOVE NORMAL TEMPERATURES WILL CONTINUE THROUGH THE SHORT TERM
PERIOD WITH THE WARM SOUTHERLY FLOW REMAINING IN PLACE UNTIL LATE
IN THE PERIOD. HIGHS ON SATURDAY WILL BE IN THE 40S AND 50S...WITH
30S AND 40S EXPECTED ON SUNDAY. MILD OVERNIGHT LOWS IN THE 30S
TONIGHT AND SATURDAY NIGHT WILL BE REPLACED BY LOWS IN THE 20S
SUNDAY NIGHT.
.LONG TERM...MONDAY THROUGH FRIDAY
A LOW PRESSURE SYSTEM WILL BE INFLUENCING THE REGION AT THE START
OF THE LONG TERM PERIOD. WITH THE EXCEPTION OF THE NAM...MOST
MODELS SHOW A GENERAL AGREEMENT WITH LARGE SCALE
FEATURES...HOWEVER VERY LITTLE CONSENSUS ON THE SMALL SCALE
DETAILS. THE GENERAL UPPER LEVEL THEME FEATURES A LONG WAVE TROUGH
CLOSING OFF OVER THE SOUTHERN PLAINS SUNDAY. THE 100+ KT JET
ROUNDS THE BASE OF THE TROUGH LIFTING THE WHOLE SYSTEM OFF TO THE
NORTHEAST. LIKEWISE THE SURFACE LOW HOOKS FROM THE OKLAHOMA
PANHANDLE TROUGH SOUTHERN IA/NORTHERN MO...THEN OFF TOWARD THE
GREAT LAKES REGION. MODELS DO DIFFER IN THEIR MOISTURE AND
FRONTOGENESIS FIELDS AND THEREFORE THE PLACEMENT OF THE HEAVIEST
QPF/SNOWFALL. IN FACT THE NEWEST RUN OF THE ECMWF BRINGS VERY
LITTLE PRECIPITATION INTO THIS CWA. DUE TO THE HIGH
UNCERTAINTY...STUCK PRETTY CLOSE TO THE SUPERBLEND GUIDANCE. BY
LATE MONDAY AND TUESDAY HOWEVER...A DRIER AND COOLER AIRMASS WILL
BE DROPPING OUT OF CANADA...AND THE REMAINDER OF THE LONG TERM IS
DRY OVERALL. FORECAST TEMPERATURES ARE NEAR TO SLIGHTLY BELOW
NORMAL THROUGH THE LONG TERM.
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
WITH THE PERSISTENT LOW LEVEL MOISTURE EXPECT THAT STRATUS/FOG
WILL RETURN INTO THE KATY/KABR REGION TONIGHT. PIR AND MBG SHOULD
STAY OUT OF THE FOG AND STRATUS CLOUDS THROUGH THE TAF PERIOD
AND REMAIN VFR.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...TMT
SHORT TERM...PARKIN
LONG TERM...SERR
AVIATION...WISE
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1130 AM CST FRI DEC 12 2014
.UPDATE...
LOW CLOUDS AND FOG CONTINUE TO HANG IN ACROSS MOST OF THE EASTERN
HALF OF THE CWA...WITH THE EXCEPTION OF AN AREA THAT HAS CLEARED
OUT PARTS OF ROBERTS AND GRANT COUNTIES. THE SOUTHWESTERN PART OF
THE STRATUS AREA LOOKS TO NOW BE ERODING...SO WILL STICK WITH A
GRADUAL EROSION OF THE CLOUDS THROUGH THE AFTERNOON FROM WEST TO
EAST. NO CHANGES MADE TO WINDS OR TEMPERATURES AT THIS TIME.
SEE UPDATED AVIATION DISCUSSION BELOW.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH SUNDAY
SAME OLD STORY WITH THE FORECAST TODAY AS LOW LEVEL MOISTURE
REMAINS TRAPPED OVER THE EASTERN CWA. AS EXPECTED...STRATUS CLOUDS
HAVE EXPANDED BACK TO THE WEST INTO THE JAMES VALLEY.
ALTHOUGH...WESTWARD PROGRESSION IS NOT AS AGGRESSIVE AS YESTERDAY
AT THIS TIME WHEN CLOUDS REACHED BACK AS FAR WEST AS THE MISSOURI
RIVER. THIS MAY MEAN A QUICKER CLEARING THROUGH THE DAY
TODAY...BUT STILL HAVE A FEW HOURS TO GO BEFORE WESTWARD EXPANSION
STOPS. HAVE BEEN CLOSELY FOLLOWING 950 MB RH FIELDS AND ESPECIALLY
THE HRRR LOW LEVEL CLOUD PRODUCT...WHICH HAS BEEN PERFORMING
TREMENDOUSLY DURING THIS STRATUS EVENT. THE HRRR NAILED YESTERDAYS
EROSION PATTERN WHICH FIRST CLEARED OUT FSD CWA THEN SHIFTED IT
NORTH TO PARTS OF NORTHEAST SD. IT IS ONCE AGAIN SHOWING SOMETHING
SIMILAR TO THIS...FIRST CLEARING OUT FSD AREA THEN WORKING INTO
NORTHEAST SD...BUT MAYBE EVEN AN HOUR OR TWO QUICKER TODAY...WHICH
IS BELIEVABLE IF CLOUDS THIS MORNING DO NOT MAKE IT AS FAR WEST AS
YESTERDAY. ALSO SEEING WIDESPREAD LIGHT FOG ONCE AGAIN...BUT VSBY
NOT REALLY TANKING OVER A WIDESPREAD AREA...JUST THE TYPICAL FOGGY
AREAS AROUND SUMMIT AND THE COTEAU REGION. WEB CAMS NOT REVEALING
ANY SUBSTANTIAL DRIZZLE...AND THAT IS NOT REALLY EXPECTED GIVEN
THE SHALLOW SATURATED LAYER. ALTHOUGH...FOG IS DEPOSITING ON
ROADWAYS WHICH WILL CREATE SOME SLICK SPOTS THIS MORNING.
MODELS/SOUNDINGS STILL INDICATE LOW LEVEL MOISTURE WILL BE TRAPPED
ACROSS THE EASTERN CWA ALL THE WAY INTO SUNDAY BEFORE THE FRONTAL
BOUNDARY FINALLY MOVES THROUGH. THIS WILL KEEP COOLER TEMPS OVER
THE EASTERN COUNTIES...ALTHOUGH THEY WILL STILL BE WELL ABOVE
NORMAL. CENTRAL SD WILL SEE VERY MILD TEMPS IN THE 50S AND 60S.
THE SATURATED LAYER BECOMES DEEP ENOUGH BY SATURDAY WHERE DRIZZLE
BECOMES A BIT MORE LIKELY...SO HAVE ADDED THAT INTO THE FORECAST
FOR EASTERN AREAS. MAY ALSO SEE SOME LIGHT RAIN AHEAD OF THE
FRONTAL BOUNDARY SATURDAY NIGHT INTO SUNDAY. TEMPS LOOK LIKE THEY
WILL BE WARM ENOUGH AND REMAIN ABOVE FREEZING TO KEEP EVERYTHING
IN THE LIQUID FORM.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
THE MODELS HAVE CHANGED DIRECTION IN THE FORECAST FOR EARLY IN THE
LONG TERM WITH THE TRACK OF A SIGNIFICANT SURFACE LOW PRESSURE
AREA. THE MODELS NOW TAKE THIS SURFACE LOW PRESSURE AREA FARTHER
NORTH TRACKING IT FROM SOUTHERN KS ON SUNDAY NIGHT NORTHEAST AND
INTO THE GREAT LAKES REGION THROUGH MONDAY NIGHT. THIS TRACK PUTS
MOST OF OUR CWA WITH HIGHER CHANCES OF SNOWFALL AS THE GEM...GFS
AND EC ALL SHOW MORE COVERAGE OF QPF. THUS...INCREASED POPS THROUGH
THIS TIME PERIOD AS THE CHANCES OF SNOWFALL ACCUMULATIONS HAVE
INCREASED. WILL HAVE HIGHER CONFIDENCE IF LATER MODEL RUNS SHOW
CONSISTENCY. THIS SYSTEM COULD ALSO HAVE QUITE A BIT OF WIND WITH
IT. OTHERWISE...COOL CANADIAN HIGH PRESSURE WILL BUILD IN FOR
TUESDAY AND REMAIN THROUGH THURSDAY. HIGHS THROUGH THE PERIOD WILL
BE CLOSER TO NORMAL IN THE 20S AND LOWER 30S. THESE MAY BE EVEN
COLDER FOR TUESDAY THROUGH THURSDAY IF WE RECEIVE NEW SOME
SNOWFALL. THERE ARE SOME INDICATIONS WE MIGHT RECEIVE SOME MORE
OVERRUNNING SNOWFALL LATE IN THE PERIOD.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
LIFR FOG/STRATUS REMAINS OVER EASTERN SOUTH DAKOTA THIS
AFTERNOON...AFFECTING THE KATY/KABR TAF SITES. SATELLITE IMAGES DO
SHOW SOME EROSION TO THE WESTERN EDGE OF THE STRATUS HOWEVER...SO
STILL EXPECTING TO SEE CLEARING AT KABR THIS AFTERNOON. WITH THE
PERSISTENT LOW LEVEL MOISTURE...DO EXPECT THAT STRATUS/FOG WILL
CONTINUE/MOVE BACK INTO THE KATY/KABR REGION TONIGHT. PIR AND MBG
SHOULD STAY OUT OF THE FOG AND STRATUS CLOUDS THROUGH THE TAF
PERIOD AND REMAIN VFR.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...PARKIN
SHORT TERM...TMT
LONG TERM...MOHR
AVIATION...SERR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
554 AM CST FRI DEC 12 2014
.UPDATE...
UPDATED 12Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...TODAY THROUGH SUNDAY
SAME OLD STORY WITH THE FORECAST TODAY AS LOW LEVEL MOISTURE
REMAINS TRAPPED OVER THE EASTERN CWA. AS EXPECTED...STRATUS CLOUDS
HAVE EXPANDED BACK TO THE WEST INTO THE JAMES VALLEY.
ALTHOUGH...WESTWARD PROGRESSION IS NOT AS AGGRESSIVE AS YESTERDAY
AT THIS TIME WHEN CLOUDS REACHED BACK AS FAR WEST AS THE MISSOURI
RIVER. THIS MAY MEAN A QUICKER CLEARING THROUGH THE DAY
TODAY...BUT STILL HAVE A FEW HOURS TO GO BEFORE WESTWARD EXPANSION
STOPS. HAVE BEEN CLOSELY FOLLOWING 950 MB RH FIELDS AND ESPECIALLY
THE HRRR LOW LEVEL CLOUD PRODUCT...WHICH HAS BEEN PERFORMING
TREMENDOUSLY DURING THIS STRATUS EVENT. THE HRRR NAILED YESTERDAYS
EROSION PATTERN WHICH FIRST CLEARED OUT FSD CWA THEN SHIFTED IT
NORTH TO PARTS OF NORTHEAST SD. IT IS ONCE AGAIN SHOWING SOMETHING
SIMILAR TO THIS...FIRST CLEARING OUT FSD AREA THEN WORKING INTO
NORTHEAST SD...BUT MAYBE EVEN AN HOUR OR TWO QUICKER TODAY...WHICH
IS BELIEVABLE IF CLOUDS THIS MORNING DO NOT MAKE IT AS FAR WEST AS
YESTERDAY. ALSO SEEING WIDESPREAD LIGHT FOG ONCE AGAIN...BUT VSBY
NOT REALLY TANKING OVER A WIDESPREAD AREA...JUST THE TYPICAL FOGGY
AREAS AROUND SUMMIT AND THE COTEAU REGION. WEB CAMS NOT REVEALING
ANY SUBSTANTIAL DRIZZLE...AND THATS NOT REALLY EXPECTED GIVEN THE
SHALLOW SATURATED LAYER. ALTHOUGH...FOG IS DEPOSITING ON ROADWAYS
WHICH WILL CREATE SOME SLICK SPOTS THIS MORNING.
MODELS/SOUNDINGS STILL INDICATE LOW LEVEL MOISTURE WILL BE TRAPPED
ACROSS THE EASTERN CWA ALL THE WAY INTO SUNDAY BEFORE THE FRONTAL
BOUNDARY FINALLY MOVES THROUGH. THIS WILL KEEP COOLER TEMPS OVER
THE EASTERN COUNTIES...ALTHOUGH THEY WILL STILL BE WELL ABOVE
NORMAL. CENTRAL SD WILL SEE VERY MILD TEMPS IN THE 50S AND 60S.
THE SATURATED LAYER BECOMES DEEP ENOUGH BY SATURDAY WHERE DRIZZLE
BECOMES A BIT MORE LIKELY...SO HAVE ADDED THAT INTO THE FORECAST
FOR EASTERN AREAS. MAY ALSO SEE SOME LIGHT RAIN AHEAD OF THE
FRONTAL BOUNDARY SATURDAY NIGHT INTO SUNDAY. TEMPS LOOK LIKE THEY
WILL BE WARM ENOUGH AND REMAIN ABOVE FREEZING TO KEEP EVERYTHING
IN THE LIQUID FORM.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
THE MODELS HAVE CHANGED DIRECTION IN THE FORECAST FOR EARLY IN THE
LONG TERM WITH THE TRACK OF A SIGNIFICANT SURFACE LOW PRESSURE
AREA. THE MODELS NOW TAKE THIS SURFACE LOW PRESSURE AREA FARTHER
NORTH TRACKING IT FROM SOUTHERN KS ON SUNDAY NIGHT NORTHEAST AND
INTO THE GREAT LAKES REGION THROUGH MONDAY NIGHT. THIS TRACK PUTS
MOST OF OUR CWA WITH HIGHER CHANCES OF SNOWFALL AS THE GEM...GFS
AND EC ALL SHOW MORE COVERAGE OF QPF. THUS...INCREASED POPS THROUGH
THIS TIME PERIOD AS THE CHANCES OF SNOWFALL ACCUMULATIONS HAVE
INCREASED. WILL HAVE HIGHER CONFIDENCE IF LATER MODEL RUNS SHOW
CONSISTENCY. THIS SYSTEM COULD ALSO HAVE QUITE A BIT OF WIND WITH
IT. OTHERWISE...COOL CANADIAN HIGH PRESSURE WILL BUILD IN FOR
TUESDAY AND REMAIN THROUGH THURSDAY. HIGHS THROUGH THE PERIOD WILL
BE CLOSER TO NORMAL IN THE 20S AND LOWER 30S. THESE MAY BE EVEN
COLDER FOR TUESDAY THROUGH THURSDAY IF WE RECEIVE NEW SOME
SNOWFALL. THERE ARE SOME INDICATIONS WE MIGHT RECEIVE SOME MORE
OVERRUNNING SNOWFALL LATE IN THE PERIOD.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
LIFR/IFR STRATUS/FOG IS EXPECTED TO REMAIN ACROSS THE EASTERN PART
OF THE REGION TODAY AND TONIGHT AS LLM CONTINUES TO STREAM UP FROM
THE SOUTH. IT WILL BE DIFFICULT TO BURN THIS OFF BUT DO EXPECT
ABR TO CLEAR OUT THIS AFTERNOON ONLY TO FOG/CLOUD BACK UP AGAIN
TONIGHT. PIR AND MBG SHOULD STAY OUT OF THE FOG AND STRATUS CLOUDS
THROUGH THE TAF PERIOD AND REMAIN VFR.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...MOHR
SHORT TERM...TMT
LONG TERM...MOHR
AVIATION...MOHR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
328 AM EST SUN DEC 14 2014
.SHORT TERM (TODAY AND TONIGHT)...MAIN CONCERNS ARE EXTENT OF LOW-
CLOUDS AND PATCHY FREEZING DENSE FOG FOR THIS MORNING. HRRR MODEL
SEEMS TO PERFORM THE BEST DURING THE PAST 24 HOURS AND WILL FOLLOW
CLOSELY FOR FORECASTING LOW-CLOUDS. CLOUD COVER WILL MAINLY BE
CONFINED ACROSS THE NORTHERN AND WESTERN COUNTIES THROUGH THE
FORECAST...EXCEPT FOR FOG DEVELOPMENT.
CLOSE DEWPOINT DEPRESSIONS...CLEAR SKY CALM WINDS HAVE ALLOWED
PATCHY DENSE FOG TO DEVELOP THIS MORNING. FOG AND TEMPERATURES
BELOW FREEZING WILL PRODUCE A GOOD DEAL OF FROST DEVELOPMENT.
FOG WILL DISSIPATE BY MID-MORNING...BUT LOW CLOUDS REMAIN...
MAINLY OVER SOUTHWEST VIRGINIA AND THE PLATEAU COUNTIES.
FOR TONIGHT...ANOTHER ROUND OF FOG DEVELOPMENT ANTICIPATED.
.LONG TERM /MONDAY THROUGH SATURDAY/... WINDS WILL VEER TO THE
SOUTHWEST AHEAD OF AN APPROACHING COLD FRONT. THESE WINDS...ALONG
WITH MOSTLY TO PARTLY SUNNY CONDITIONS WILL ALLOW FOR AN EVEN WARMER
DAY ONCE ANY LINGERING OVERNIGHT FOG/CLOUD COVER DISSIPATES...WITH
HIGHS IN THE 55 TO 60 DEGREE RANGE IN MOST LOCATIONS. AS THE FRONT
SLOWLY MOVES INTO THE AREA...CLOUDS WILL INCREASE AND SCATTERED
SHOWERS WILL OVERSPREAD THE REGION OVER THE COURSE OF THE NIGHT AND
INTO THE MORNING HOURS ON TUESDAY....BEFORE TAPERING OFF BY MIDDAY.
HOWEVER...SOME WRAP AROUND MOISTURE AND A PERSISTENT INVERSION MAY
KEEP LOW CLOUDS IN /PARTICULARLY ACROSS THE NORTHERN HALF OF THE
AREA/ THROUGH THE DAY ON TUESDAY AND EVEN INTO WEDNESDAY. AFTER A
BRIEF BOUT OF RIDGING ON THURSDAY...ANOTHER BROAD UPPER-TROUGH WILL
SWING FROM THE LOWER-MISSISSIPPI VALLEY INTO THE AREA LATE FRIDAY
INTO SATURDAY...BRINGING SOME DECENT CHANCES FOR PRECIPITATION AND
SOME COOLER TEMPERATURES HEADING INTO THIS WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 53 31 62 47 / 0 0 20 60
KNOXVILLE MCGHEE TYSON AIRPORT, TN 49 29 60 44 / 0 0 10 60
OAK RIDGE, TN 46 29 59 45 / 0 0 20 60
TRI CITIES AIRPORT, TN 48 24 59 40 / 0 0 10 50
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
304 PM EST SAT DEC 13 2014
.SHORT TERM...(TONIGHT THROUGH MONDAY)...FORECAST FOR TONIGHT AND
SUNDAY WILL BE HEAVILY INFLUENCED BY HOW FAR SE THE LOW CLOUD
LAYER MOVES AFTER SUNSET. THE NAM AND RAP MODELS DEPICTION OF 925
MB RH CLOSELY RESEMBLED SATELLITE PICS THIS AFTERNOON...AND WAS
CLOSELY FOLLOWED FOR GUIDANCE TONIGHT. ONLY MINOR TWEAKS IN GENERAL
AS PREVIOUS GRIDS TOOK THE BROKEN TO OVERCAST CLOUD LAYER TO ALL
BUT EXTREME SRN VALLEY COUNTIES OF SE TN AND SW NC. NO PATCHY FOG
NEAR LAKES AND STREAMS...BUT I DID ADD A VERY LOW POP FOR PATCHY
LIGHT RAIN...DRIZZLE OR FREEZING DRIZZLE TO SW VA AND PARTS OF NE
TN. THIS MESHES WELL WITH OUR NWS NEIGHBORS...AND WILL BE ADDED TO
THE AFTERNOON HWO PRODUCT.
THOSE CLOUDS SHOULD ERODE DURING THE LATE MORNING AND AFTERNOON
SUNDAY...BUT COULD LINGER AT LEAST PARTLY CLOUDY FOR SW VA AND NE
TN WELL INTO EARLY SUNDAY NIGHT. THESE CLOUDS EXIT MONDAY JUST
BEFORE CLOUDS ADVANCE FROM THE WEST WITH THE APPROACH OF THE
CENTRAL PLAINS LOW PRESSURE SYSTEM. GFS/ECMWF/SREF ALL INDICATE NOT
MUCH CHANCE OF ANY PRECIPITATION UNTIL VERY LATE MONDAY AFTERNOON
FOR OUR WRN MOST COUNTIES. THUS...I FAVORED THE MILDER GFS MAXES
MONDAY AS NAM MOS MAXES CONTINUE TO BE ON THE COOL SIDE WITH LITTLE
SUPPORT.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)...MID LATITUDE CYCLONE
MOVES ACROSS THE SOUTHERN APPALACHIAN REGION MONDAY NIGHT THROUGH
TUESDAY NIGHT GENERATING SHOWERS. AS THE SYSTEM IS DEPARTING TUESDAY
NIGHT ENOUGH COLD AIR WILL HAVE BUILT INTO THE FORECAST AREA FOR A
COUPLE SNOW FLURRIES IN THE HIGHER TERRAIN ACROSS SOUTHWEST VIRGINIA
AND NORTHEAST TENNESSEE. THE RETURNING ZONAL CONFIGURATION ALLOWS
FOR A DRY WEDNESDAY HOWEVER WEAK SHORT WAVE ENERGY SLIDING ACROSS
THE MID SOUTH MAY LEAD TO THE POSSIBILITY OF A SHOWER ON THURSDAY.
BETTER RAIN CHANCES WILL BE BACK IN THE PICTURE FRIDAY INTO SATURDAY
WITH GOOD CHANCE TO LIKELY POPS. THERE ARE MODEL DIFFERENCES WITH
THIS SYSTEM WITH THE ECMWF COLDER AND DEEPER WITH A LITTLE BETTER
CHANCE OF SOME FROZEN PRECIPITATION WHILE THE GFS IS MORE
PROGRESSIVE AND WARMER DURING THIS END OF WEEK PERIOD. WILL AWAIT
FUTURE MODEL DEPICTION OF THIS PERIOD FOR FORECAST FINE TUNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 33 56 31 61 / 10 0 0 20
KNOXVILLE MCGHEE TYSON AIRPORT, TN 30 52 30 59 / 10 0 0 10
OAK RIDGE, TN 32 50 30 58 / 10 0 0 20
TRI CITIES AIRPORT, TN 27 47 25 58 / 10 0 0 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1105 PM CST SAT DEC 13 2014
.AVIATION...
AVIATION CONCERNS WITH THIS TAF PACKAGE WILL BE MVFR TO IFR CIGS
TONIGHT/SUNDAY MORNING AND THUNDERSTORM CHANCES SUNDAY.
VAD WIND PROFILES FROM BOTH FWS AND GRK INDICATE A 35 KNOT LOW
LEVEL JET HAS SET UP ALREADY. LOW CLOUDS WERE DEVELOPING ACROSS
SOUTH TEXAS AND THE HILL COUNTRY LATE THIS EVENING AND THESE
CLOUDS SHOULD REACH ALL TAF SITES BETWEEN 06Z AND 07Z. CEILINGS
SHOULD FALL A BIT OVERNIGHT WITH SOME 800 TO 1000 FT CEILINGS
LIKELY BETWEEN 10Z AND 16Z. EXPECT LIFTING CEILINGS AFTER 16Z BUT
VFR CONDITIONS WILL MOST LIKELY NOT RETURN UNTIL LATE SUNDAY AFTERNOON.
LARGE SCALE LIFT WILL BE ON THE INCREASE OVERNIGHT AS A 4 CORNERS
UPPER LOW DEEPENS AND MOVES EAST/NORTHEAST. SCATTERED LIGHT
SHOWERS SUNDAY MORNING WILL INCREASE IN COVERAGE AND INTENSITY
THROUGH THE DAY SUNDAY. MID LEVEL INSTABILITY WILL SUPPORT
THUNDERSTORMS...MAINLY SUNDAY AFTERNOON. THE BEST WINDOW OF TIME
FOR STORMS AT THE METROPLEX TAF SITES WILL BE BETWEEN 20Z AND 00Z.
THUNDER IS LESS LIKELY IN WACO MAINLY DUE TO THE NORTHERN TRACK OF
THE UPPER LOW. ALL PRECIPITATION SHOULD MOVE EAST OF THE TAF SITES
EARLY SUNDAY EVENING AS A PUNCH OF DRY AIR COMES IN ON THE BACK
SIDE OF THE DEPARTING UPPER LOW.
SOUTHERLY WINDS WILL PREVAIL THROUGH SUNDAY AFTERNOON AT SPEEDS
BETWEEN 12 AND 19 KNOTS ALONG WITH A FEW HIGHER GUSTS...ESPECIALLY
SUNDAY AFTERNOON. THE WIND DIRECTION WILL BECOME MORE SOUTHWEST SUNDAY
EVENING AS THE SURFACE LOW MOVES INTO CENTRAL KANSAS AND A COLD
FRONT SWEEPS ACROSS THE STATE. WIND SPEEDS SHOULD DECREASE
SLIGHTLY SUNDAY NIGHT WHEN WIND DIRECTION BECOMES MORE SOUTHWESTERLY.
HOWEVER...SOME CROSS WIND ISSUES ARE LIKELY MONDAY WHEN WIND
SPEEDS INCREASE.
79
&&
.UPDATE...
SURFACE OBS AT MID EVENING CONTINUE TO SHOW A WEAK BOUNDARY NORTH
OF ARDMORE OKLAHOMA TO PARIS OR JUST TO THE NORTH OF SHREVEPORT.
CONSIDERABLE LOW CLOUDINESS AND FOG WERE OCCURRING ALONG AND NORTH
OF THE BOUNDARY. EXPECT AREAS NORTH OF PARIS WILL CONTINUE TO HAVE
SOME MIST OR FOG THE REST OF THE EVENING.
AN INCREASING LOW LEVEL JET IS DEVELOPING ACROSS THE REGION PER
BOTH KGRK AND KFWS 88D VAD WIND PROFILES. THIS WILL RESULT IN
INCREASING CLOUD COVER AS THE NIGHT PROGRESSES AND AREAS FOG
BEFORE DAYBREAK. BECAUSE OF INCREASED WIND SPEEDS IN THE OVERNIGHT
HOURS...WE DO NOT FEEL THE FOG WILL BECOME DENSE WITH MOST
LOCATIONS REMAINING ABOVE 3 MILES.
AS FOR TOMORROWS SYSTEM...MODELS ARE IN FAIRLY GOOD AGREE THAT THE
PRECIPITATION WILL BE ALONG AND AHEAD OF THE COLD FRONT AND THAT
AMOUNTS UP TO 1 INCH ARE MORE LIKELY ALONG AND NORTH OF I-20 AND
OVER THE EASTERN COUNTIES. THE CONVECTION SHOULD BE SCATTERED DURING THE
MORNING HOURS BUT WILL BECOME MORE LINEAR ALONG THE FRONT DURING
THE AFTERNOON AS IT PUSHES THROUGH THE METROPLEX AND INTO THE
EASTERN COUNTIES. WE ARE RELYING ON THE GFS/NAM/TT WRF SOLUTIONS
FOR FRONTAL TIMING AND CONVECTION COVERAGE AS THE HRRR IS NOT
AVAILABLE THIS EVENING. AS STATED OVER THE PAST FEW DAYS...STRONG
TO MARGINAL SEVERE THUNDERSTORMS ARE POSSIBLE DURING THE AFTERNOON
AND EVENING HOURS DUE TO INCREASING INSTABILITY AND SOME CAPE
DURING THE AFTERNOON.
ONLY MINOR SHORT-TERM CHANGES MADE TO THE PREVIOUS FORECAST
PACKAGE. 75
&&
.PREV DISCUSSION... /ISSUED 358 PM CST SAT DEC 13 2014/
THE 3 PM SURFACE ANALYSIS INDICATED THAT A WARM FRONT HAD ALMOST
EXITED NORTH TEXAS...EXTENDING FROM NORTH OF GAINESVILLE AND
DENISON TO NEAR PARIS. WINDS WERE GENERALLY SOUTH AND SOUTHEAST TO
THE SOUTH OF THE BOUNDARY AND TEMPERATURES WERE IN THE UPPER 60S
TO MID 70S WHILE TO THE NORTH OF THE BOUNDARY WINDS WERE EASTERLY
AND TEMPERATURES WERE MOSTLY IN THE 50S.
EXPECT SKIES TO BECOME MOSTLY CLOUDY AREA WIDE TONIGHT. THE WARM
FRONT WILL CONTINUE TO LIFT NORTH OVERNIGHT AS A SURFACE LOW
DEEPENS OVER SOUTHEASTERN COLORADO. AREAS OF FOG WILL LIKELY
DEVELOP OVERNIGHT. SOME OF THE MODEL GUIDANCE ARE INDICATING THE
POTENTIAL FOR SOME DENSE FOG...BUT GIVEN THE FORECAST WIND
SPEEDS...WILL NOT MENTION THAT AT THIS TIME.
AS AN UPPER LEVEL LOW THAT IS CURRENTLY OVER NORTHWESTERN ARIZONA
MOVES EAST AND THEN NORTHEAST...SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS WEST TEXAS
OVERNIGHT. SOME OF THIS ACTIVITY WILL MOVE INTO THE WESTERN PART
OF THE NORTH TEXAS ZONES AROUND DAYBREAK AND MOVE EAST DURING THE
DAY SUNDAY. GIVEN THE STEEP LAPSE RATES...AND DECENT SHEAR...SOME
STRONG THUNDERSTORMS ARE POSSIBLE. THERE LIKELY BE LIMITED
INSTABILITY BUT STILL CANNOT RULE OUT SOME ISOLATED SEVERE STORMS
THAT WOULD PRODUCE LARGE HAIL AND DAMAGING WINDS.
THE RAIN WILL END FROM WEST TO EAST LATE SUNDAY AFTERNOON THROUGH
MONDAY MORNING...THOUGH SOME VERY LOW CHANCES OF MAY LINGER IN THE
EXTREME SOUTHEAST INTO MONDAY AFTERNOON.
LOW RAIN CHANCES WILL RETURN OVERNIGHT TUESDAY NIGHT AND WEDNESDAY
AS AN UPPER LEVEL DISTURBANCE MOVES IN FROM THE SOUTHWEST. AS A
LARGE UPPER LEVEL TROUGH MOVES EAST FROM THE SOUTHWESTERN U.S. WE
WILL CONTINUE TO SEE CHANCES OF SHOWERS...WITH SOME THUNDERSTORMS
LIKELY THURSDAY/THURSDAY NIGHT. RAIN CHANCES SHOULD BE ON THE
DECREASE FRIDAY AFTERNOON INTO FRIDAY NIGHT AS THE TROUGH MOVES TO
OUR EAST. THE ECMWF...GFS...AND CMC DISAGREE SOME ON THE TIMING
AND STRENGTH OF UPPER LEVEL TROUGH...BUT WE SHOULD SEE A DECENT
CHANCE OF RAIN WITH THIS SYSTEM. 58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 58 71 50 64 40 / 5 70 40 5 5
WACO, TX 57 71 49 67 39 / 5 50 40 5 5
PARIS, TX 54 67 51 62 36 / 5 60 80 10 5
DENTON, TX 57 70 46 62 35 / 5 80 20 5 5
MCKINNEY, TX 57 68 48 63 36 / 5 80 40 5 5
DALLAS, TX 58 69 50 64 41 / 5 70 40 5 5
TERRELL, TX 57 70 53 64 39 / 5 60 60 10 5
CORSICANA, TX 58 71 54 67 40 / 5 50 60 10 5
TEMPLE, TX 58 71 52 68 39 / 5 40 50 5 5
MINERAL WELLS, TX 56 72 42 63 34 / 5 50 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
79/75
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
936 PM CST SAT DEC 13 2014
.UPDATE...
SURFACE OBS AT MID EVENING CONTINUE TO SHOW A WEAK BOUNDARY NORTH
OF ARDMORE OKLAHOMA TO PARIS OR JUST TO THE NORTH OF SHREVEPORT.
CONSIDERABLE LOW CLOUDINESS AND FOG WERE OCCURRING ALONG AND NORTH
OF THE BOUNDARY. EXPECT AREAS NORTH OF PARIS WILL CONTINUE TO HAVE
SOME MIST OR FOG THE REST OF THE EVENING.
AN INCREASING LOW LEVEL JET IS DEVELOPING ACROSS THE REGION PER
BOTH KGRK AND KFWS 88D VAD WIND PROFILES. THIS WILL RESULT IN
INCREASING CLOUD COVER AS THE NIGHT PROGRESSES AND AREAS FOG
BEFORE DAYBREAK. BECAUSE OF INCREASED WIND SPEEDS IN THE OVERNIGHT
HOURS...WE DO NOT FEEL THE FOG WILL BECOME DENSE WITH MOST
LOCATIONS REMAINING ABOVE 3 MILES.
AS FOR TOMORROWS SYSTEM...MODELS ARE IN FAIRLY GOOD AGREE THAT THE
PRECIPITATION WILL BE ALONG AND AHEAD OF THE COLD FRONT AND THAT
AMOUNTS UP TO 1 INCH ARE MORE LIKELY ALONG AND NORTH OF I-20 AND
OVER THE EASTERN COUNTIES. THE CONVECTION SHOULD BE SCATTERED DURING THE
MORNING HOURS BUT WILL BECOME MORE LINEAR ALONG THE FRONT DURING
THE AFTERNOON AS IT PUSHES THROUGH THE METROPLEX AND INTO THE
EASTERN COUNTIES. WE ARE RELYING ON THE GFS/NAM/TT WRF SOLUTIONS
FOR FRONTAL TIMING AND CONVECTION COVERAGE AS THE HRRR IS NOT
AVAILABLE THIS EVENING. AS STATED OVER THE PAST FEW DAYS...STRONG
TO MARGINAL SEVERE THUNDERSTORMS ARE POSSIBLE DURING THE AFTERNOON
AND EVENING HOURS DUE TO INCREASING INSTABILITY AND SOME CAPE
DURING THE AFTERNOON.
ONLY MINOR SHORT-TERM CHANGES MADE TO THE PREVIOUS FORECAST
PACKAGE. 75
&&
.AVIATION...
/ISSUED 602 PM CST SAT DEC 13 2014/
VFR CONDITIONS ARE EXPECTED THROUGH THE EVENING AT ALL NORTH TEXAS
TAF SITES WITH A SOUTH WIND IN THE 10 TO 15 KNOT RANGE. A 40 KNOT
LOW LEVEL JET WILL DEVELOP LATE THIS EVENING IN RESPONSE TO
DEEPENING SURFACE LOW PRESSURE ACROSS THE CENTRAL HIGH PLAINS. AN
INFLUX OF LOW LEVEL MOISTURE WILL RESULT IN THE RETURN OF MVFR TO
IFR CEILINGS SHORTLY AFTER MIDNIGHT AT ALL TAF SITES. THE LOW
CEILINGS WILL LINGER THROUGH THE MORNING HOURS SUNDAY AND SLOWLY
LIFT DURING THE AFTERNOON.
LARGE SCALE LIFT ASSOCIATED WITH A STRONG UPPER LEVEL LOW PRESSURE
SYSTEM WILL BE ON THE INCREASE THROUGH THE MORNING HOURS SUNDAY.
THE INCREASING LIFT WILL ACT TO DESTABILIZE THE ATMOSPHERE AND
RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS...ESPECIALLY SUNDAY
AFTERNOON. IT APPEARS THAT STORMS WILL NOT BECOME ORGANIZED UNTIL
THEY MOVE EAST OF THE INTERSTATE 35 CORRIDOR. THEREFORE...WE WILL
ONLY CARRY PREVAILING THUNDER AT THE METRO TERMINALS BETWEEN 20Z AND
23Z. SOME SHOWERS MAY LINGER IN THE REGION THROUGH SUNDAY EVENING
BUT THESE SHOWERS SHOULD HAVE LITTLE IMPACT TO AVIATION TRAFFIC.
79
&&
.PREV DISCUSSION... /ISSUED 358 PM CST SAT DEC 13 2014/
THE 3 PM SURFACE ANALYSIS INDICATED THAT A WARM FRONT HAD ALMOST
EXITED NORTH TEXAS...EXTENDING FROM NORTH OF GAINESVILLE AND
DENISON TO NEAR PARIS. WINDS WERE GENERALLY SOUTH AND SOUTHEAST TO
THE SOUTH OF THE BOUNDARY AND TEMPERATURES WERE IN THE UPPER 60S
TO MID 70S WHILE TO THE NORTH OF THE BOUNDARY WINDS WERE EASTERLY
AND TEMPERATURES WERE MOSTLY IN THE 50S.
EXPECT SKIES TO BECOME MOSTLY CLOUDY AREA WIDE TONIGHT. THE WARM
FRONT WILL CONTINUE TO LIFT NORTH OVERNIGHT AS A SURFACE LOW
DEEPENS OVER SOUTHEASTERN COLORADO. AREAS OF FOG WILL LIKELY
DEVELOP OVERNIGHT. SOME OF THE MODEL GUIDANCE ARE INDICATING THE
POTENTIAL FOR SOME DENSE FOG...BUT GIVEN THE FORECAST WIND
SPEEDS...WILL NOT MENTION THAT AT THIS TIME.
AS AN UPPER LEVEL LOW THAT IS CURRENTLY OVER NORTHWESTERN ARIZONA
MOVES EAST AND THEN NORTHEAST...SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS WEST TEXAS
OVERNIGHT. SOME OF THIS ACTIVITY WILL MOVE INTO THE WESTERN PART
OF THE NORTH TEXAS ZONES AROUND DAYBREAK AND MOVE EAST DURING THE
DAY SUNDAY. GIVEN THE STEEP LAPSE RATES...AND DECENT SHEAR...SOME
STRONG THUNDERSTORMS ARE POSSIBLE. THERE LIKELY BE LIMITED
INSTABILITY BUT STILL CANNOT RULE OUT SOME ISOLATED SEVERE STORMS
THAT WOULD PRODUCE LARGE HAIL AND DAMAGING WINDS.
THE RAIN WILL END FROM WEST TO EAST LATE SUNDAY AFTERNOON THROUGH
MONDAY MORNING...THOUGH SOME VERY LOW CHANCES OF MAY LINGER IN THE
EXTREME SOUTHEAST INTO MONDAY AFTERNOON.
LOW RAIN CHANCES WILL RETURN OVERNIGHT TUESDAY NIGHT AND WEDNESDAY
AS AN UPPER LEVEL DISTURBANCE MOVES IN FROM THE SOUTHWEST. AS A
LARGE UPPER LEVEL TROUGH MOVES EAST FROM THE SOUTHWESTERN U.S. WE
WILL CONTINUE TO SEE CHANCES OF SHOWERS...WITH SOME THUNDERSTORMS
LIKELY THURSDAY/THURSDAY NIGHT. RAIN CHANCES SHOULD BE ON THE
DECREASE FRIDAY AFTERNOON INTO FRIDAY NIGHT AS THE TROUGH MOVES TO
OUR EAST. THE ECMWF...GFS...AND CMC DISAGREE SOME ON THE TIMING
AND STRENGTH OF UPPER LEVEL TROUGH...BUT WE SHOULD SEE A DECENT
CHANCE OF RAIN WITH THIS SYSTEM. 58
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 58 71 50 64 40 / 5 70 40 5 5
WACO, TX 57 71 49 67 39 / 5 50 40 5 5
PARIS, TX 54 67 51 62 36 / 5 60 80 10 5
DENTON, TX 57 70 46 62 35 / 5 80 20 5 5
MCKINNEY, TX 57 68 48 63 36 / 5 80 40 5 5
DALLAS, TX 58 69 50 64 41 / 5 70 40 5 5
TERRELL, TX 57 70 53 64 39 / 5 60 60 10 5
CORSICANA, TX 58 71 54 67 40 / 5 50 60 10 5
TEMPLE, TX 58 71 52 68 39 / 5 40 50 5 5
MINERAL WELLS, TX 56 72 42 63 34 / 5 50 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/75
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1139 AM CST SAT DEC 13 2014
.DISCUSSION...
SEE 18Z AVIATION DISCUSSION.
&&
.AVIATION...
MVFR CIGS BEGINNING TO DEVELOP ACROSS SE TX. NAM 12 AND GFS
INITIALIZED POORLY SO LEANED TOWARD A RAP AND LAV GUIDANCE BLEND.
CIGS SHOULD BRIEFLY MIX OUT TOWARD EVENING BEFORE FILLING BACK IN
BETWEEN 03-06Z. COULD BE SOME BRIEF IFR CIGS BEFORE SUNRISE. WINDS
EXPECTED TO BE A BIT STRONGER ON SUNDAY AND ADDED A GUST GROUP TO
IAH TAF AFTER 18Z. 43
&&
.PREV DISCUSSION... /ISSUED 1018 AM CST SAT DEC 13 2014/
UPDATE...
THE CLUSTER OF SHOWERS OVER THE FAR OFFSHORE WATERS BETWEEN HIGH
ISLAND AND FREEPORT IS LIKELY CAUSED BY A WEAKNESS ALONG THE
UNDERSIDE OF A SHEARING OUT ARKLATEX BROAD UPPER LOW. SLIGHT TO
LOW END POPS OVER THE MARITIME REGION TODAY TO ACCOUNT FOR THIS
SLOW MOVING RAIN OR SHOWER ACTIVITY. AN APPROACHING WESTERN CONUS
LONG WAVE TROUGH HAS PLACED A DOWNSTREAM AMPLIFIED RIDGE OVER THE
EASTERN TWO THIRDS OF THE NATION...U.S. MIDWEST SURFACE HIGH AND
LOWERING ROCKY MOUNTAIN PRESSURES WILL MAINTAIN A PERSISTENT
SOUTHEASTERLY FETCH THROUGH THE WEEKEND. TODAY...PARTIALLY CLOUDY
SKIES WITH A LIGHT SPIT OR SHOWER CLOSER TO THE COAST...AFTERNOON
TEMPERATURES WARM INTO THE LOWER TO MIDDLE 70S. BETTER WARM AIR
ADVECTION PATTERN TOMORROW AS THE AFOREMENTIONED WESTERN OPEN WAVE
TROUGH BECOMES A CUT-OFF LOW AND ENTERS THE LEES OF THE ROCKIES.
CWA MAY GET CLIPPED BY THIS NORTHEASTERN-EXITING FEATURE...NORTHERN
THIRD FA POPS TO INCREASE TO MODERATE CHANCE TOMORROW AFTERNOON
AND EVENING FOR PRIMARILY SHOWERS. 31
PREV DISCUSSION... /ISSUED 430 AM CST SAT DEC 13 2014/
DISCUSSION...
LATEST SFC ANALYSIS SHOWS HIGH PRESSURE STRETCHING FROM MISS
RIVER VALLEY TOWARD E TX. RIDGE AXIS HAS ALLOWED FOR WINDS TO
DECOUPLE AND WITH MOSTLY CLEAR SKIES FOG HAS DEVELOPED ACROSS MUCH
OF THE AREA. METRO HOUSTON MAY BE THE LONE EXCEPTION BUT EVEN SOME
OF THE SUBURBS ARE REPORTING RESTRICTED VISIBILITY. AFTER FOG
DISSIPATES SKIES SHOULD BE PARTLY CLOUDY WITH LOW LEVEL WINDS
INCREASING FROM THE SOUTH AS LOW PRESSURE ORGANIZES IN THE LEE OF
THE ROCKIES.
UPPER LEVEL ANALYSIS THIS MORNING HAS A RATHER AMPLIFIED PATTERN
WITH A DEEP LOW OVER NEW ENGLAND...RIDGING OVER THE PLAINS AND A
DEEP TROUGH OVER THE GREAT BASIN/DESERT SW. A SHORTWAVE TROUGH
CONTINUES TO ROTATE OVER THE ARKLATEX BEFORE MOVING EAST TODAY.
FORECAST MODELS ARE IN PRETTY GOOD AGREEMENT WITH MOVING THE DEEP
TROUGH OUT WEST TOWARDS THE C PLAINS ON SUNDAY. WARM ADVECTION
WILL CONTINUE THROUGH THE WEEKEND AND LIKELY SUPPORT SHOWER
ACTIVITY ACROSS THE AREA. OVERALL 20/30 POPS SHOULD COVER RAIN
CHANCES AND THERE MAY BE SOME MORE PATCHY FOG WITH THE INCREASE OF
MOISTURE FROM THE GULF.
UPPER LEVEL LOW MOVES TOWARDS THE MIDWEST ON MONDAY WHICH SHOULD
SWING A COLD FRONT THROUGH THE AREA. WHILE HIGHER RAIN CHANCES
REMAIN IN THE FORECAST IT DOES NOT LOOK LIKE RAINFALL TOTALS WILL
BE ALL THAT IMPRESSIVE. PRECIP WATER VALUES MAY REACH 1.3 INCHES
AND CAPE WILL BE LUCKY TO REACH 500 J/KG. THERE IS JUST ENOUGH
INSTABILITY TO MENTION TSRA BUT LIKELY HAVE JUST SOME STRONGER
SHOWERS. FRONT SHOULD PUSH INTO THE GULF LATE MON WITH HIGH
PRESSURE BUILDING INTO THE PLAINS ON TUE.
TUE INTO WED THE NEXT UPPER LEVEL SYSTEM DIGS TOWARDS THE BAJA
PENINSULA AND S ROCKIES. WARM ADVECTION AND ISENTROPIC LIFT OVER
THE FRONT STALLED IN THE GULF SHOULD CONTRIBUTE TO INCREASED CLOUD
COVER. GFS/ECMWF DIFFER ON HOW FAR THE FRONT PUSHES INTO THE GULF
WITH THE ECMWF PUSHING THE FRONT WELL INTO THE GULF. FORECAST WILL
GO WITH 20/30 POPS ON WED FOR SHOWER ACTIVITY GIVEN ISENTROPIC
ASCENT AND WARM ADVECTION PATTERN. GFS BRINGS THE STALLED FRONT
NORTH AS A WARM FRONT ON WED. THE ECMWF IS LESS AGGRESSIVE WITH
BRINGING THE WARM FRONT NORTH. AS A RESULT THERE ARE SOME 10-12
DEGREE TEMPERATURE DIFFERENCES BETWEEN THE MODELS. FORECAST WILL
KEEP A BLEND OF THE MODEL TEMPS WITH SOME HEDGING TOWARDS THE GFS.
GIVEN THE UPPER LEVEL PATTERN AND THE FRONT PULLING PARALLEL TO
THE FLOW...THINK THE FRONT STALLING IN THE GULF CLOSER TO THE GFS
SOLUTION IS MORE LIKELY AT THIS POINT. THE NEXT UPPER LEVEL TROUGH
UPSTREAM APPROACHING TX ALSO SUPPORTS THIS IDEA.
THURSDAY THROUGH THE END OF THE WEEK WILL HAVE INCREASED RAIN
CHANCES AS THIS NEXT UPPER LEVEL TROUGH MOVES ACROSS TX. THE 00Z
ECMWF IS NOW MUCH FASTER THAN ITS PREVIOUS 12Z RUN AND CLOSER TO
THE LATEST 00/06Z GFS COUNTERPARTS. THE FORECAST WILL GO WITH
MAINLY 40 POPS THUR/FRI NEXT WEEK AS THE TROUGH MOVES ACROSS. IT
LOOKS LIKE THERE MAY BE ENOUGH MOISTURE/INSTABILITY TO BETTER
SUPPORT TSRA BUT ANY STORMS SHOULD REMAIN BELOW SEVERE LEVELS.
PRECIP WATER VALUES REACH 1.5 INCHES OR CLOSE TO 2 STANDARD
DEVIATIONS ABOVE NORMAL. WE WILL HAVE TO WATCH THIS TIME FRAME FOR
HEAVY RAINFALL THREAT BUT SEEING THE INCONSISTENCY IN THE MODELS
SUSPECT THIS PART OF THE FORECAST WILL CHANGE QUITE A BIT IN THE
COMING DAYS. A COLD FRONT WITH THE SYSTEM SHOULD PUSH THROUGH FRI
NIGHT WITH A COLDER AIRMASS MOVING INTO THE AREA AGAIN. 39
MARINE...
ONSHORE FLOW WILL PERSIST THROUGH THE WEEKEND AS AN UPPER LEVEL
DISTURBANCE APPROACHES THE SOUTHERN PLAINS. THIS SYSTEM WILL BRING
A FRONT OFF THE COAST LATE MONDAY EVENING BUT WINDS WILL QUICKLY
TURN AROUND WITH ONSHORE FLOW RESUMING BY WEDNESDAY MORNING.
ANOTHER FRONTAL PASSAGE IS EXPECTED LATE IN THE WEEK AS THE NEXT
UPPER DISTURBANCE APPROACHES THE STATE. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 72 59 73 61 71 / 10 10 40 50 20
HOUSTON (IAH) 73 57 73 63 75 / 10 10 30 50 50
GALVESTON (GLS) 70 61 70 63 71 / 20 10 20 20 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...31
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1121 AM CST FRI DEC 12 2014
.AVIATION...
FOG CONDITIONS HAVE FINALLY SCOURED OUT AT ALL THREE TAF SITES
LATE THIS MORNING...THUS LEADING TO VFR VIS. HOWEVER CLOUD DECKS ARE A
DIFFERENT STORY AS MVFR...IFR AND LIFR DECKS PERSISTED AT
KCDS...KPVW AND KLBB RESPECTIVELY...WITH KCDS GOING UP AND DOWN IN
CATEGORY. WILL EXPECT A BRIEF PERIOD OF DECKS IMPROVING TO FEW-SCT
MVFR AT KLBB AND KPVW LATER THIS AFTN...HOWEVER BKN-OVC MVFR TO
IFR DECKS WILL LIKELY HOLD STRONG AT KCDS. TONIGHT...VIS WILL
DETERIORATE ONCE AGAIN AT ALL THREE TAF SITES...FALLING TO IFR TO
POSSIBLY VLIFR. CLOUD DECKS WILL ALSO DROP CATEGORY
OVERNIGHT...FALLING TO IFR TO LIFR. OTHERWISE...LIGHT SOUTH TO
SOUTHWEST WINDS WILL ENDURE. CAN NOT RULE OUT -DZ LATE
TONIGHT/EARLY SATURDAY MORNING...THOUGH CONFIDENCE IS NOT HIGH
ENOUGH TO INSERT A MENTION AT THIS TIME.
&&
PREV DISCUSSION... /ISSUED 339 AM CST FRI DEC 12 2014/
SHORT TERM...
LOW CLOUDS AND AREAS OF FOG WERE AGAIN VISITING THE SOUTH PLAINS
REGION EARLY THIS MORNING AS SHALLOW MOISTURE CONTINUES TO LINGER IN
THE REGION. DENSE FOG WAS NOTED AT KGNC...KHOB AND KCVN...THOUGH AS
OF 09Z ONLY LIGHT FOG /VISIBILITIES AROUND 4 SM/ WAS PRESENT AT KLBB
AND KPVW. RECENT RUNS OF THE HRRR AND RAP DO CONTINUE TO SUGGEST THE
DENSE FOG WILL EXPAND OVER MUCH OF THE CAPROCK THROUGH THE EARLY
MORNING HOURS...AND THIS SEEMS VALID GIVEN THE MOISTURE ADVECTION
WITHIN LIGHT SOUTHWESTERLY SURFACE FLOW. SATELLITE SUGGESTS THAT
CLOUD COVER AND FOG COVERAGE IS NOT AS EXTENSIVE IN THE ROLLING
PLAINS...THOUGH KCDS HAS BEEN OCCASIONALLY REPORTING DENSE FOG.
GIVEN THIS...WE WILL MAINTAIN THE DENSE FOG ADVISORY AS IS FOR NOW
/ON THE CAPROCK THROUGH 10 AM/...BUT WILL REASSESS AROUND 6 AM AND
ADJUST IF NEEDED. THE FOG SHOULD GRADUALLY LIFT/THIN BY MID/LATE
MORNING...WITH SUN RETURNING TO A GOOD CHUNK OF THE CWA BY
MID-AFTERNOON. OBVIOUSLY...THE EXTENT AND DURATION OF THE FOG AND
CLOUD COVER WILL DICTATE EXACTLY HOW WARM EACH LOCATION GETS...BUT
MOST SPOTS SHOULD TOP OUT IN THE MIDDLE TO UPPER 60S.
A RELATIVELY NARROW BUT HIGH-AMPLITUDE UPPER RIDGE ALOFT WILL SLOWLY
TRAVERSE THE REGION THROUGH TONIGHT AS A SHORTWAVE TROUGH DROPS FROM
EASTERN NEBRASKA EARLY THIS MORNING THROUGH OKLAHOMA TODAY AND THEN
INTO THE SOUTHERN MISSISSIPPI RIVER VALLEY BY EARLY SATURDAY. THIS
SHORTWAVE WILL HAVE LITTLE IMPACT ON WEST TEXAS WEATHER THOUGH
CONTINUED MOIST SOUTHERLY SURFACE FLOW COUPLED WITH THE LONG NIGHTS
WILL PROVIDE ANOTHER OPPORTUNITY FOR THE DEVELOPMENT OF LOW CLOUDS
AND AREAS OF DENSE FOG TONIGHT. THE MOIST CONDITIONS WILL KEEP
TEMPERATURES MILD FOR MID-DECEMBER...WITH LOWS MOSTLY IN THE 40S TO
LOW 50S...THOUGH THE NORTHWEST ZONES COULD DIP IN THE 30S.
LONG TERM...
A PROGRESSIVE SPLIT-FLOW PATTERN WILL BRING ACTIVE WEATHER TO WEST
TEXAS FOR MUCH OF THE NEXT WEEK OR SO...
A VIGOROUS SHORTWAVE TROUGH CURRENTLY DOUSING MUCH OF CALIFORNIA
WILL BE APPROACHING WEST TEXAS BY LATE SATURDAY. THE LATEST
GUIDANCE IS IN PRETTY GOOD AGREEMENT THAT THE CORE OF THE SYSTEM
WILL MOVE FROM NRN NM EAST-NORTHEAST ACROSS THE OKLA AND NRN TX
PANHANDLE DURING THE DAY SUNDAY. LIFT FROM THIS WAVE WILL BEGIN TO
SPREAD OVER THE REGION BY SATURDAY NIGHT. MUCH OF THE GUIDANCE
BEGINS TO DEVELOP PRECIPITATION ACROSS THE WESTERN SOUTH PLAINS
AFTER MIDNIGHT...WHICH MAY EVOLVE INTO A RAGGED SQUALL-LINE AS
AN INBOUND PACIFIC-TYPE FRONT FOCUSES THE FORCING. WE HAVE
INCREASED AND EXPANDED POPS ACROSS MUCH OF THE CWA AS CONFIDENCE
INCREASES IN THE DEVELOPMENT OF PRECIPITATION. STRONG WIND SHEAR
AND MARGINAL INSTABILITY MAY LEAD TO A FEW STRONGER UPDRAFTS AND
SOME HAIL POTENTIAL WITH THE ACTIVITY. THIS WILL BE A QUICK SHOT
OF PRECIP THOUGH...AS THE DRY SLOT SWIFTLY WORKS IN ACROSS WEST
TEXAS SUNDAY MORNING. PRECIP CHANCES SHOULD BE EAST OF THE FA BY
AFTERNOON AND IT APPEARS THAT ANY WRAP-AROUND MOISTURE WILL
REMAIN TO OUR NORTH. IT WILL ALSO BE BREEZY BEHIND THE PACIFIC-
FRONT DURING THE DAY SUNDAY. A COLD FRONT WILL DROP THROUGH THE
REGION ON MONDAY AND KNOCK TEMPS BACK DOWN INTO THE 50S FOR HIGHS
FOR MONDAY AND TUESDAY. MEANWHILE...ANOTHER UPPER WAVE WILL BE
MOVING FROM THE WEST COAST THROUGH THE INTER-MOUNTAIN WEST AND
DESERT SOUTHWEST AND MAY BEGIN TO AFFECT OUR WEATHER AS EARLY AS
LATE WEDNESDAY. QUITE A BIT OF UNCERTAINTY STILL SURROUNDS THE
TRACK AND STRENGTH OF THIS SYSTEM....BUT IN GENERAL IT LOOKS LIKE
A FAVORABLE SETUP FOR RAIN COULD MATERIALIZE CENTERED ON
THURSDAY...AND WE/VE ADDED CHANCE POPS DURING THIS PERIOD FOR
MOST OF THE FA. LOOKING FARTHER OUT...ANOTHER STORM SYSTEM MAY
THREATEN THE AREA NEXT WEEKEND OR EARLY THE FOLLOWING WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 68 38 67 41 56 / 0 0 0 50 20
TULIA 66 44 69 47 58 / 0 0 0 60 30
PLAINVIEW 65 45 68 48 59 / 0 0 0 50 30
LEVELLAND 67 43 69 47 59 / 0 0 0 50 20
LUBBOCK 66 47 68 50 61 / 0 0 0 50 20
DENVER CITY 67 44 68 45 59 / 0 0 0 40 20
BROWNFIELD 67 45 69 48 61 / 0 0 0 40 20
CHILDRESS 66 49 67 53 66 / 0 10 10 40 70
SPUR 66 49 68 52 65 / 0 0 10 30 40
ASPERMONT 67 51 69 54 68 / 10 0 10 30 50
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
29
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
624 AM CST FRI DEC 12 2014
.UPDATE...
WE HAVE EXPANDED THE DENSE FOG ADVISORY TO INCLUDE THE SOUTHEAST
TEXAS PANHANDLE AND FAR NORTHERN ROLLING PLAINS...IN ADDITION TO
MUCH OF THE SOUTH PLAINS. THE ADVISORY REMAINS IN EFFECT UNTIL 10
AM.
KCDS HAS REMAINED MIRED IN DENSE FOG FOR MUCH OF THE LAST SEVERAL
HOURS AND THE MEMPHIS SHERIFF/S OFFICE CONFIRMED DENSE FOG
THERE. HENCE WE HAVE GONE AHEAD AND EXPANDED THE DENSE FOG
ADVISORY TO INCLUDE THE NORTHEAST ZONES. CALLS FURTHER TO THE
SOUTH INCLUDING TO THE DICKENS AND ASPERMONT SHERIFF OFFICES
REVEALED ONLY LIGHT FOG THERE...SO WE HAVE OMITTED THEM FROM THE
ADVISORY. THE DENSITY OF THE FOG UP ON THE CAPROCK HAS VARIED
QUITE A BIT...BUT AT LEAST SOME SITES ON THE PERIPHERY OF THE CWA
CONTINUE TO REPORT OCCASIONAL DENSE FOG. GIVEN THIS AND THE NEARLY
SATURATED CONDITIONS AND CONTINUED LOW-LEVEL MOISTURE
ADVECTION...WOULD EXPECTED AT LEAST AREAS OF DENSE FOG ACROSS THE
CAPROCK AND WILL CONTINUE THE DENSE FOG ADVISORY THROUGH 16Z.
THERE ARE INDICATIONS BY THE HRRR AND RAP THAT A POCKET OF DENSE
FOG COULD EVEN PERSIST UNTIL 17-18Z ACROSS THE WESTERN ZONES...AND
A PORTION OF THE ADVISORY MAY EVEN NEED TO BE EXTENDED SLIGHTLY IN
TIME LATER THIS MORNING. THE UPDATED PRODUCTS HAVE BEEN SENT.
&&
.PREV DISCUSSION... /ISSUED 547 AM CST FRI DEC 12 2014/
AVIATION...
ABUNDANT LOW-LEVEL MOISTURE WAS PROVIDING ANOTHER ROUND OF LOW
CLOUDS AND FOG WITH IFR/LIFR CONDITIONS IN PLACE EARLY THIS
MORNING. THE TERMINALS SHOULD SEE GRADUAL IMPROVEMENTS LATE THIS
MORNING INTO EARLY THIS AFTERNOON...AND KPVW AND KLBB SHOULD
RETURN TO VFR BY EARLY TO MID-AFTERNOON...THOUGH MVFR CIGS COULD
PERSIST AT KCDS THROUGH THE AFTERNOON. ANOTHER BOUT OF LOW CLOUDS
AND FOG WILL FOLLOW TONIGHT WITH POOR FLYING WEATHER RETURNING TO
THE TERMINALS.
PREV DISCUSSION... /ISSUED 339 AM CST FRI DEC 12 2014/
SHORT TERM...
LOW CLOUDS AND AREAS OF FOG WERE AGAIN VISITING THE SOUTH PLAINS
REGION EARLY THIS MORNING AS SHALLOW MOISTURE CONTINUES TO LINGER IN
THE REGION. DENSE FOG WAS NOTED AT KGNC...KHOB AND KCVN...THOUGH AS
OF 09Z ONLY LIGHT FOG /VISIBILITIES AROUND 4 SM/ WAS PRESENT AT KLBB
AND KPVW. RECENT RUNS OF THE HRRR AND RAP DO CONTINUE TO SUGGEST THE
DENSE FOG WILL EXPAND OVER MUCH OF THE CAPROCK THROUGH THE EARLY
MORNING HOURS...AND THIS SEEMS VALID GIVEN THE MOISTURE ADVECTION
WITHIN LIGHT SOUTHWESTERLY SURFACE FLOW. SATELLITE SUGGESTS THAT
CLOUD COVER AND FOG COVERAGE IS NOT AS EXTENSIVE IN THE ROLLING
PLAINS...THOUGH KCDS HAS BEEN OCCASIONALLY REPORTING DENSE FOG.
GIVEN THIS...WE WILL MAINTAIN THE DENSE FOG ADVISORY AS IS FOR NOW
/ON THE CAPROCK THROUGH 10 AM/...BUT WILL REASSESS AROUND 6 AM AND
ADJUST IF NEEDED. THE FOG SHOULD GRADUALLY LIFT/THIN BY MID/LATE
MORNING...WITH SUN RETURNING TO A GOOD CHUNK OF THE CWA BY
MID-AFTERNOON. OBVIOUSLY...THE EXTENT AND DURATION OF THE FOG AND
CLOUD COVER WILL DICTATE EXACTLY HOW WARM EACH LOCATION GETS...BUT
MOST SPOTS SHOULD TOP OUT IN THE MIDDLE TO UPPER 60S.
A RELATIVELY NARROW BUT HIGH-AMPLITUDE UPPER RIDGE ALOFT WILL SLOWLY
TRAVERSE THE REGION THROUGH TONIGHT AS A SHORTWAVE TROUGH DROPS FROM
EASTERN NEBRASKA EARLY THIS MORNING THROUGH OKLAHOMA TODAY AND THEN
INTO THE SOUTHERN MISSISSIPPI RIVER VALLEY BY EARLY SATURDAY. THIS
SHORTWAVE WILL HAVE LITTLE IMPACT ON WEST TEXAS WEATHER THOUGH
CONTINUED MOIST SOUTHERLY SURFACE FLOW COUPLED WITH THE LONG NIGHTS
WILL PROVIDE ANOTHER OPPORTUNITY FOR THE DEVELOPMENT OF LOW CLOUDS
AND AREAS OF DENSE FOG TONIGHT. THE MOIST CONDITIONS WILL KEEP
TEMPERATURES MILD FOR MID-DECEMBER...WITH LOWS MOSTLY IN THE 40S TO
LOW 50S...THOUGH THE NORTHWEST ZONES COULD DIP IN THE 30S.
LONG TERM...
.A PROGRESSIVE SPLIT-FLOW PATTERN WILL BRING ACTIVE WEATHER TO WEST
TEXAS FOR MUCH OF THE NEXT WEEK OR SO...
A VIGOROUS SHORTWAVE TROUGH CURRENTLY DOUSING MUCH OF CALIFORNIA
WILL BE APPROACHING WEST TEXAS BY LATE SATURDAY. THE LATEST
GUIDANCE IS IN PRETTY GOOD AGREEMENT THAT THE CORE OF THE SYSTEM
WILL MOVE FROM NRN NM EAST-NORTHEAST ACROSS THE OKLA AND NRN TX
PANHANDLE DURING THE DAY SUNDAY. LIFT FROM THIS WAVE WILL BEGIN TO
SPREAD OVER THE REGION BY SATURDAY NIGHT. MUCH OF THE GUIDANCE
BEGINS TO DEVELOP PRECIPITATION ACROSS THE WESTERN SOUTH PLAINS
AFTER MIDNIGHT...WHICH MAY EVOLVE INTO A RAGGED SQUALL-LINE AS
AN INBOUND PACIFIC-TYPE FRONT FOCUSES THE FORCING. WE HAVE
INCREASED AND EXPANDED POPS ACROSS MUCH OF THE CWA AS CONFIDENCE
INCREASES IN THE DEVELOPMENT OF PRECIPITATION. STRONG WIND SHEAR
AND MARGINAL INSTABILITY MAY LEAD TO A FEW STRONGER UPDRAFTS AND
SOME HAIL POTENTIAL WITH THE ACTIVITY. THIS WILL BE A QUICK SHOT
OF PRECIP THOUGH...AS THE DRY SLOT SWIFTLY WORKS IN ACROSS WEST
TEXAS SUNDAY MORNING. PRECIP CHANCES SHOULD BE EAST OF THE FA BY
AFTERNOON AND IT APPEARS THAT ANY WRAP-AROUND MOISTURE WILL
REMAIN TO OUR NORTH. IT WILL ALSO BE BREEZY BEHIND THE PACIFIC-
FRONT DURING THE DAY SUNDAY. A COLD FRONT WILL DROP THROUGH THE
REGION ON MONDAY AND KNOCK TEMPS BACK DOWN INTO THE 50S FOR HIGHS
FOR MONDAY AND TUESDAY. MEANWHILE...ANOTHER UPPER WAVE WILL BE
MOVING FROM THE WEST COAST THROUGH THE INTER-MOUNTAIN WEST AND
DESERT SOUTHWEST AND MAY BEGIN TO AFFECT OUR WEATHER AS EARLY AS
LATE WEDNESDAY. QUITE A BIT OF UNCERTAINTY STILL SURROUNDS THE
TRACK AND STRENGTH OF THIS SYSTEM....BUT IN GENERAL IT LOOKS LIKE
A FAVORABLE SETUP FOR RAIN COULD MATERIALIZE CENTERED ON
THURSDAY...AND WE/VE ADDED CHANCE POPS DURING THIS PERIOD FOR
MOST OF THE FA. LOOKING FARTHER OUT...ANOTHER STORM SYSTEM MAY
THREATEN THE AREA NEXT WEEKEND OR EARLY THE FOLLOWING WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 68 38 67 41 56 / 0 0 0 50 20
TULIA 66 44 69 47 58 / 0 0 0 60 30
PLAINVIEW 65 45 68 48 59 / 0 0 0 50 30
LEVELLAND 67 43 69 47 59 / 0 0 0 50 20
LUBBOCK 66 47 68 50 61 / 0 0 0 50 20
DENVER CITY 67 44 68 45 59 / 0 0 0 40 20
BROWNFIELD 67 45 69 48 61 / 0 0 0 40 20
CHILDRESS 66 49 67 53 66 / 0 10 10 40 70
SPUR 66 49 68 52 65 / 0 0 10 30 40
ASPERMONT 67 51 69 54 68 / 10 0 10 30 50
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: TXZ021>036-039>041.
&&
$$
23/33
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
547 AM CST FRI DEC 12 2014
.AVIATION...
ABUNDANT LOW-LEVEL MOISTURE WAS PROVIDING ANOTHER ROUND OF LOW
CLOUDS AND FOG WITH IFR/LIFR CONDITIONS IN PLACE EARLY THIS
MORNING. THE TERMINALS SHOULD SEE GRADUAL IMPROVEMENTS LATE THIS
MORNING INTO EARLY THIS AFTERNOON...AND KPVW AND KLBB SHOULD
RETURN TO VFR BY EARLY TO MID-AFTERNOON...THOUGH MVFR CIGS COULD
PERSIST AT KCDS THROUGH THE AFTERNOON. ANOTHER BOUT OF LOW CLOUDS
AND FOG WILL FOLLOW TONIGHT WITH POOR FLYING WEATHER RETURNING TO
THE TERMINALS.
&&
.PREV DISCUSSION... /ISSUED 339 AM CST FRI DEC 12 2014/
SHORT TERM...
LOW CLOUDS AND AREAS OF FOG WERE AGAIN VISITING THE SOUTH PLAINS
REGION EARLY THIS MORNING AS SHALLOW MOISTURE CONTINUES TO LINGER IN
THE REGION. DENSE FOG WAS NOTED AT KGNC...KHOB AND KCVN...THOUGH AS
OF 09Z ONLY LIGHT FOG /VISIBILITIES AROUND 4 SM/ WAS PRESENT AT KLBB
AND KPVW. RECENT RUNS OF THE HRRR AND RAP DO CONTINUE TO SUGGEST THE
DENSE FOG WILL EXPAND OVER MUCH OF THE CAPROCK THROUGH THE EARLY
MORNING HOURS...AND THIS SEEMS VALID GIVEN THE MOISTURE ADVECTION
WITHIN LIGHT SOUTHWESTERLY SURFACE FLOW. SATELLITE SUGGESTS THAT
CLOUD COVER AND FOG COVERAGE IS NOT AS EXTENSIVE IN THE ROLLING
PLAINS...THOUGH KCDS HAS BEEN OCCASIONALLY REPORTING DENSE FOG.
GIVEN THIS...WE WILL MAINTAIN THE DENSE FOG ADVISORY AS IS FOR NOW
/ON THE CAPROCK THROUGH 10 AM/...BUT WILL REASSESS AROUND 6 AM AND
ADJUST IF NEEDED. THE FOG SHOULD GRADUALLY LIFT/THIN BY MID/LATE
MORNING...WITH SUN RETURNING TO A GOOD CHUNK OF THE CWA BY
MID-AFTERNOON. OBVIOUSLY...THE EXTENT AND DURATION OF THE FOG AND
CLOUD COVER WILL DICTATE EXACTLY HOW WARM EACH LOCATION GETS...BUT
MOST SPOTS SHOULD TOP OUT IN THE MIDDLE TO UPPER 60S.
A RELATIVELY NARROW BUT HIGH-AMPLITUDE UPPER RIDGE ALOFT WILL SLOWLY
TRAVERSE THE REGION THROUGH TONIGHT AS A SHORTWAVE TROUGH DROPS FROM
EASTERN NEBRASKA EARLY THIS MORNING THROUGH OKLAHOMA TODAY AND THEN
INTO THE SOUTHERN MISSISSIPPI RIVER VALLEY BY EARLY SATURDAY. THIS
SHORTWAVE WILL HAVE LITTLE IMPACT ON WEST TEXAS WEATHER THOUGH
CONTINUED MOIST SOUTHERLY SURFACE FLOW COUPLED WITH THE LONG NIGHTS
WILL PROVIDE ANOTHER OPPORTUNITY FOR THE DEVELOPMENT OF LOW CLOUDS
AND AREAS OF DENSE FOG TONIGHT. THE MOIST CONDITIONS WILL KEEP
TEMPERATURES MILD FOR MID-DECEMBER...WITH LOWS MOSTLY IN THE 40S TO
LOW 50S...THOUGH THE NORTHWEST ZONES COULD DIP IN THE 30S.
LONG TERM...
..A PROGRESSIVE SPLIT-FLOW PATTERN WILL BRING ACTIVE WEATHER TO WEST
TEXAS FOR MUCH OF THE NEXT WEEK OR SO...
A VIGOROUS SHORTWAVE TROUGH CURRENTLY DOUSING MUCH OF CALIFORNIA
WILL BE APPROACHING WEST TEXAS BY LATE SATURDAY. THE LATEST
GUIDANCE IS IN PRETTY GOOD AGREEMENT THAT THE CORE OF THE SYSTEM
WILL MOVE FROM NRN NM EAST-NORTHEAST ACROSS THE OKLA AND NRN TX
PANHANDLE DURING THE DAY SUNDAY. LIFT FROM THIS WAVE WILL BEGIN TO
SPREAD OVER THE REGION BY SATURDAY NIGHT. MUCH OF THE GUIDANCE
BEGINS TO DEVELOP PRECIPITATION ACROSS THE WESTERN SOUTH PLAINS
AFTER MIDNIGHT...WHICH MAY EVOLVE INTO A RAGGED SQUALL-LINE AS
AN INBOUND PACIFIC-TYPE FRONT FOCUSES THE FORCING. WE HAVE
INCREASED AND EXPANDED POPS ACROSS MUCH OF THE CWA AS CONFIDENCE
INCREASES IN THE DEVELOPMENT OF PRECIPITATION. STRONG WIND SHEAR
AND MARGINAL INSTABILITY MAY LEAD TO A FEW STRONGER UPDRAFTS AND
SOME HAIL POTENTIAL WITH THE ACTIVITY. THIS WILL BE A QUICK SHOT
OF PRECIP THOUGH...AS THE DRY SLOT SWIFTLY WORKS IN ACROSS WEST
TEXAS SUNDAY MORNING. PRECIP CHANCES SHOULD BE EAST OF THE FA BY
AFTERNOON AND IT APPEARS THAT ANY WRAP-AROUND MOISTURE WILL
REMAIN TO OUR NORTH. IT WILL ALSO BE BREEZY BEHIND THE PACIFIC-
FRONT DURING THE DAY SUNDAY. A COLD FRONT WILL DROP THROUGH THE
REGION ON MONDAY AND KNOCK TEMPS BACK DOWN INTO THE 50S FOR HIGHS
FOR MONDAY AND TUESDAY. MEANWHILE...ANOTHER UPPER WAVE WILL BE
MOVING FROM THE WEST COAST THROUGH THE INTER-MOUNTAIN WEST AND
DESERT SOUTHWEST AND MAY BEGIN TO AFFECT OUR WEATHER AS EARLY AS
LATE WEDNESDAY. QUITE A BIT OF UNCERTAINTY STILL SURROUNDS THE
TRACK AND STRENGTH OF THIS SYSTEM....BUT IN GENERAL IT LOOKS LIKE
A FAVORABLE SETUP FOR RAIN COULD MATERIALIZE CENTERED ON
THURSDAY...AND WE/VE ADDED CHANCE POPS DURING THIS PERIOD FOR
MOST OF THE FA. LOOKING FARTHER OUT...ANOTHER STORM SYSTEM MAY
THREATEN THE AREA NEXT WEEKEND OR EARLY THE FOLLOWING WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 68 38 67 41 56 / 0 0 0 50 20
TULIA 66 44 69 47 58 / 0 0 0 60 30
PLAINVIEW 65 45 68 48 59 / 0 0 0 50 30
LEVELLAND 67 43 69 47 59 / 0 0 0 50 20
LUBBOCK 66 47 68 50 61 / 0 0 0 50 20
DENVER CITY 67 44 68 45 59 / 0 0 0 40 20
BROWNFIELD 67 45 69 48 61 / 0 0 0 40 20
CHILDRESS 66 49 67 53 66 / 0 10 10 40 70
SPUR 66 49 68 52 65 / 0 0 10 30 40
ASPERMONT 67 51 69 54 68 / 10 0 10 30 50
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: TXZ021>024-027>030-033>036-039>041.
&&
$$
23/33/23
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
256 AM CST SUN DEC 14 2014
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 255 AM CST SUN DEC 14 2014
THE MAIN FORECAST CONCERN CONTINUES TO BE THE PRECIPITATION
CHANCES THROUGH THE PERIOD.
LOCAL OBSERVATIONS CONTINUE TO SHOW DENSE FOG WITH VISIBILITIES OF
A QUARTER MILE OR LESS COVERING A GOOD SHARE OF THE AREA. THE
14.05Z RAP BUFKIT SOUNDINGS SUGGEST THE WINDS JUST ABOVE THE
SURFACE MAY DIMINISH A LITTLE BIT THROUGH THE REST OF THE NIGHT
INTO SUNDAY MORNING WITH A SLOWLY DEEPENING SATURATED LAYER. THIS
MAY ALLOW THE DENSE FOG TO BECOME A LITTLE MORE WIDESPREAD AND FOR
THE AREAS THAT HAVE DECENT VISIBILITY TO GO DOWN SOME. PLAN TO
LEAVE THE DENSE FOG ADVISORY IN PLACE WITH NO CHANGES.
STILL DEALING WITH THE ISSUE OF HOW MUCH IF ANY DRIZZLE IS
OCCURRING WITH THE FOG. BASED ON PERSONAL OBSERVATIONS...MUCH LESS
DRIZZLE WAS OCCURRING IN THE LOCAL AREA SATURDAY EVENING THAN
PREVIOUS NIGHTS. THE RAP CONTINUES TO SUGGEST THAT WHAT OMEGA
THERE WILL BE IN THE SATURATED LAYER WILL BE VERY NEAR THE TOP OF
THIS LAYER. THE 14.00Z GFS ALSO CONTINUES TO SHOW JUST SOME VERY
WEAK ISENTROPIC UP GLIDE OF 1 UBAR/S OR LESS ON THE 290K SURFACE.
WILL MAINTAIN THE MENTION OF DRIZZLE FOR THE ENTIRE DAY...BUT WILL
LOWER THE PRECIPITATION CHANCES OF MEASURABLE DOWN TO THE 2O TO 30
PERCENT RANGE. THIS WILL ALSO GIVE AREAS INSTEAD OF WIDESPREAD
DRIZZLE WHICH MOST LIKELY WILL BETTER FIT THE SCENARIO AS WELL.
THE MAIN PRECIPITATION EVENT STILL LOOKS TO MONDAY AND MONDAY
NIGHT. THE UPPER LEVEL LOW LIFTING OUT OF THE DESERT SOUTHWEST IS
EXPECTED TO MOVE INTO THE LOWER MISSOURI RIVER VALLEY TONIGHT AS
ANOTHER UPPER LEVEL LOW DROPS SOUTH FROM CENTRAL CANADA. EVEN
THOUGH THE MAIN UPPER LEVEL RIDGE WILL BE OVER THE EASTERN
CONUS...THE GFS SUGGESTS A SECONDARY RIDGE AXIS WILL EXTEND OFF
THE MAIN RIDGE AXIS ACROSS THE UPPER MIDWEST BETWEEN THE TWO UPPER
LEVEL LOWS. THIS WOULD KEEP THE MAJORITY OF THE FORCING AWAY FROM
THE AREA WITH THE GFS SUGGESTING JUST SOME WEAK QG CONVERGENCE
OCCURRING ACROSS THE WESTERN SECTIONS OF THE AREA WITH JUST THE
VERY WEAK ISENTROPIC UP GLIDE CONTINUING ON THE 290K SURFACE. WILL
TRIM THE RAIN CHANCES BACK TO THE 20 TO 40 PERCENT RANGE FOR THE
EVENING AND THEN ALLOW AN INCREASE TO 60 PERCENT ACROSS THE WEST
FOR LATE TONIGHT.
THE UPPER LEVEL LOW FROM THE SOUTHWEST IS THEN EXPECTED TO MOVE
ACROSS THE AREA MONDAY INTO MONDAY NIGHT BRINGING MODERATE TO
STRONG PV ADVECTION IN THE 500-300 MB ACROSS THE AREA. THE QG
CONVERGENCE WILL BECOME DEEP THROUGH THE 1000-300 MB LAYER AND
SHOULD BE MODERATE IN STRENGTH. THE ISENTROPIC UP GLIDE AHEAD OF
THE LOW WILL ALSO INCREASE WITH THE GFS SHOWING UP TO 10 UBAR/S ON
THE 290K SURFACE BY MONDAY AFTERNOON. WITH THE INCREASED
FORCING...EXPECT THE PRECIPITATION TO BECOME PRETTY WIDESPREAD AND
WILL HAVE 70 TO 80 PERCENT CHANCES FOR THE ENTIRE AREA.
TEMPERATURES WILL CONTINUE TO BE WARM ENOUGH TO KEEP THIS AS ALL
RAIN. THE FORCING WILL NOT START TO DECREASE UNTIL LATE MONDAY
NIGHT...SO WILL CONTINUE WITH THE HIGH PRECIPITATION CHANCES UNTIL
DROPPING THEM DOWN TO ABOUT 60 PERCENT IN THE SOUTHWEST BY LATE
MONDAY NIGHT. BY THIS TIME...THE SURFACE WILL HAVE PASSED BY THE
REGION ALLOWING COLDER AIR TO SPREAD ACROSS THE REGION. THIS WILL
ALLOW FOR A TRANSITION OVER TO SNOW MONDAY NIGHT INTO TUESDAY
MORNING. NOT EXPECTING ANY MIXED PRECIPITATION ISSUES WITH ICE
REMAINING IN THE CLOUDS UNTIL THE PRECIPITATION COMES TO AN END.
SNOWFALL AMOUNTS NOT EXPECTED TO A WHOLE LOT WITH MAYBE UP TO A
HALF INCH OF ACCUMULATION FOR PORTIONS OF SOUTHEAST MINNESOTA
INTO NORTH CENTRAL WISCONSIN.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 255 AM CST SUN DEC 14 2014
FINALLY STARTING TO SEE A CONSENSUS BETWEEN THE MODELS WITH HOW
THE CANADIAN UPPER LEVEL LOW IS HANDLED. THE GFS LOOKS TO HAVE
COME AROUND TO SHOWING THE SAME EVOLUTION THAT THE ECMWF HAS BEEN
SHOWING FOR SEVERAL RUNS. THE UPPER LEVEL LOW IS EXPECTED TO COME
DOWN OVER THE NORTHERN GREAT LAKES TUESDAY NIGHT AND CONTINUE TO
BE PROGRESSIVE AND MOVE OFF THE NORTHEAST COAST THURSDAY NIGHT.
THIS WILL ALLOW HIGH PRESSURE TO BUILD IN AT THE SURFACE BEHIND
THE EARLY WEEK SYSTEM AND THEN REMAIN OVER THE UPPER MIDWEST FOR
THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1120 PM CST SAT DEC 13 2014
VISIBILITY HAS IMPROVED SLIGHTLY LATE THIS EVENING INTO THE 1/2 TO
1 1/2SM RANGE. EXPECT THIS TO CONTINUE THROUGH THE NIGHT AT KLSE WITH
FURTHER DECREASES TO 1/4SM MAINLY AT KRST SOMETIME AFTER 14.09Z.
LOWER VISIBILITY POSSIBLE AT KLSE...BUT CONFIDENCE NOT HIGH
ENOUGH TO INCLUDE IN 14.06Z TAF ISSUANCE. CEILINGS FROM 200 TO 300
FT AGL WILL CONTINUE THROUGH THE NIGHT AND INTO SUNDAY MORNING
WITH VERY LITTLE IMPROVEMENT AFTER 14.17Z. VISIBILITY FORECAST TO
DROP AGAIN AFTER 15.00Z TO 1SM OR LESS IN FOG/MIST.
&&
.CLIMATE...
ISSUED AT 255 AM CST SUN DEC 14 2014
UNSEASONABLY MILD AIR REMAINS OVER THE AREA TODAY. THE RECORD HIGH
AT ROCHESTER IS 52 AND 56 FOR LA CROSSE. WHILE IT DOES NOT LOOK
LIKE LA CROSSE WILL COME CLOSE TO SETTING A RECORD...IT WILL BE
VERY CLOSE FOR ROCHESTER WITH A CURRENT FORECAST OF 51. THE
CLOUDY SKIES AND FOG MAY END UP BEING THE LIMITING FACTOR IF
TEMPERATURES DO NOT WARM AS MUCH AS EXPECTED.
ON THE OTHER HAND...IT LOOKS LIKE WE STAND A VERY GOOD CHANCE AT
BREAKING THE RECORD WARM LOWS FOR TODAY. THE CURRENT RECORD WARM
LOW AT ROCHESTER IS 37 SET IN 1928 WHILE LA CROSSE IS 41 SET IN
1891. THE CURRENT EXPECTATION IS THAT TEMPERATURES WILL REMAIN IN
THE 40S THROUGH MIDNIGHT TONIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR WIZ017-029-032>034-
041>044-053>055-061.
MN...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR MNZ079-086>088-
094>096.
IA...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR IAZ008>011-018-019-
029-030.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...ROGERS
CLIMATE...04
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1137 AM CST SAT DEC 13 2014
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
AND NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 1131 AM CST SAT DEC 13 2014
VSYBS HAVE EDGE UP A BIT...MAINLY OVER THE SRN PART OF THE FCST
AREA. THAT IS LIKELY MAINLY DUE TO WLY WINDS AT 6-10 KTS
GENERATING A LITTLE MIXING OF THE LOW-LEVELS. BUT THE OVERALL WX
SITN REMAINS UNCHANGED. INCREASINGLY MOIST AIR WL FLOW NWD OVER
THE SNOW COVER...CONTINUING TO GENERATE LOW CLDS AND FOG. EXPECT
VSBYS AND CIGS TO START EDGING DOWN AGAIN ARND DUSK...PROBABLY
HITTING THE DECK THIS EVENING. ALTHOUGH WE PROBABLY COULD GET BY
WITHOUT THE DENSE FOG ADVISORY RIGHT NOW...STILL PRETTY CONFIDENT
IT WL BE NEEDED LATER TDA. SO PLAN TO BRIDGE THROUGH THE SLIGHT
IMPROVEMENT IN CONDITIONS BY EXPLAINING THE SITN IN THE TEXT OF
THE NPW AND AN SPS.
UPDATE
ISSUED AT 841 AM CST SAT DEC 13 2014
FAIRLY DENSE FOG HAS EXPANDED INTO ERN WI...WITH THE NE CORNER OF
THE STATE THE ONLY AREA WITH VSBYS ABV 1 MILE. SO WL EXPAND THE
ADVISORY INTO E-C WI.
HARD TO SEE MUCH IMPROVEMENT IN THE FG SITN DURING THE DAY AS HIGH
DWPTS /ABV 32F/ STARTING TO HEAD NEWD OVER THE SNOWPACK. BOTH THE
RAP AND HRRR VSBY PROGS KEEP FOG THROUGH THE END OF THEIR MODEL
RUNS. WL EXPAND THE ADVISORY INTO THE NE CORNER OF THE FCST AREA
STARTING AT 18Z TDA...AND EXTEND THE ADVISORY ACRS THE ENTIRE
AREA THROUGH TO 18Z TOMORROW. EVEN THAT MAY NOT BE SUFFICIENT...BUT
MAY HAVE CHEWED AWAY AT ENOUGH OF THE SNOWCOVER OVER AT LEAST THE
SWRN PART OF THE FCST AREA TO ALLOW FOR SOME IMPROVEMENT TOMORROW
AFTN.
UPDATED PRODUCT SUITE OUT ASAP.
UPDATE
ISSUED AT 552 AM CST SAT DEC 13 2014
WEB CAMS AND OBSERVATIONS SUPPORT ADDING A FEW MORE COUNTIES TO
THE DENSE FOG ADVISORY. THIS INCLUDES WINNEBAGO AND OUTAGAMIE
COUNTY.
&&
.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 254 AM CST SAT DEC 13 2014
CLOUD/FOG TRENDS ALONG WITH LIGHT PCPN WILL BE THE PRIMARY ISSUE
THROUGH SUNDAY.
EARLY THIS MORNING MUCH OF THE FORECAST AREA WAS UNDER BLANKET OF
STRATUS AND FOG. SATELLITE IMAGERY DID SHOW A SMALL POCKET OF
CLEAR SKIES OVER FAR NORTHEAST WISCONSIN NEAR IMT...WITH A MORE
SIGNIFICANT CLEAR REGION WORKING OVER SOUTHWEST WISCONSIN. THIS
CLEARING REGION MAY BRUSH WAUSHARA COUNTY EARLY THIS MORNING BUT
RAPIDLY DEVELOPING STRATUS OVER IOWA WAS QUICKLY FILLING IN THIS
HOLE. GUIDANCE SUGGESTS SKIES TO GO PARTLY CLOUDY THIS AFTERNOON
OVER CENTRAL AND EAST CENTRAL WISCONSIN. IT IS A SMALL POSSIBILITY
DUE TO THE INCREASING WINDS/GRADIENT ACROSS THE AREA. WILL CONTINUE TO
TREND TO MORE CLOUDS FOR NOW.
THIS INCREASING SOUTHWEST FLOW WAS ALSO ALLOWING INCREASING
DEWPOINTS TO WORK OVER THE SNOW COVER EARLY THIS MORNING WITH
WIDESPREAD DENSE FOG OVER WESTERN WISCONSIN STARTING TO SPILL INTO
CENTRAL AND NORTH CENTRAL WISCONSIN. WILL ISSUE A DENSE FOG
ADVISORY FOR THESE LOCATIONS THROUGH MOST OF THE MORNING HOURS AND
MONITOR FOR ANY NEEDED EXPANSION TO THE EAST.
MODELS IN GOOD AGREEMENT WITH LIGHT MEASUREABLE PCPN EVENTUALLY
SPREADING OVER THE AREA THROUGH SUNDAY. CONTINUED INCREASING
DEWPOINTS WILL FURTHER SATURATE THE BOUNDARY LAYER AND MAY
PROMPT ANOTHER DENSE FOG ADVISORY HEADLINE LATE TONIGHT INTO
SUNDAY.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 254 AM CST SAT DEC 13 2014
MEAN FLOW STILL EXPECTED TO SPLIT OVER THE ERN PACIFIC WITH A NRN
STREAM RUNNING ACROSS SRN CANADA (WITH AN OCNL DIP INTO THE NRN
TIER OF STATES) AND A SRN BRANCH RUNNING ACROSS THE SRN HALF OF
THE CONUS. AN ACTIVE START TO THE WORK WEEK AS AN INITIAL SRN
STREAM SYSTEM LIFTS NE INTO THE GREAT LAKES AND BRINGS RAIN...
THEN SNOW TO WI. WEATHER TO TURN QUIET THRU MID-WEEK WITH HI PRES
IN CONTROL...BEFORE ATTENTION TURNS TO THE NEXT SRN STREAM SYSTEM
WHICH MODELS DISAGREE WITH THE EVENTUAL TRACK FOR LATE NEXT WEEK.
TEMPS TO BE MUCH ABOVE NORMAL THRU MON WITH READINGS FALLING TO
ONLY SLIGHTLY ABOVE NORMAL FOR THE BULK OF NEXT WEEK.
SRN STREAM SYSTEM TO BE MOVING ACROSS THE CNTRL/SRN PLAINS SUNDAY
NGT AND CONTINUING TO PUMP WARM/MOIST AIR INTO WI ON S-SW WINDS.
THE DEPTH OF THE SATURATION WL CONT TO INCREASE THRU THE NGT...
THUS AREAS OF DRIZZLE MAY TURN TO RAIN CHCS AFTER MIDNGT.
OTHERWISE...A CLOUDY/MILD NGT IN STORE AND WL HAVE TO WATCH THE
FOG THICKNESS AS LOCALLY DENSE CONDITIONS/POSSIBLE HEADLINES CAN`T
BE RULED OUT. MIN TEMPS TO RANGE FROM THE UPR 30S TO LWR 40S.
THE SYSTEM IS PROGGED TO LIFT NE INTO THE MIDWEST ON MON AND WITH
MID-LEVEL FORCING/LIFT ON THE INCREASE INTO WI...WE SHOULD SEE
PCPN CHCS ALSO ON THE INCREASE. HIGHER QPF AMOUNTS SHOULD STILL BE
TO OUR SW CLOSER TO THE SYSTEM...THUS THE HIGHEST POPS HAVE BEEN
PLACED OVER CNTRL WI (LIKELY). MON TO BE THE LAST OF THE MILD DAYS
WITH MAX TEMPS TO RANGE FROM THE LWR 40S NORTH...MID TO UPR 40S
E-CNTRL WI.
MODELS HAVE FINALLY COME INTO FAIRLY GOOD AGREEMENT BY TAKING THIS
SYSTEM INTO THE WRN GREAT LAKES MON NGT (THE SFC LOW TO REACH
ROUGHLY SE WI/SRN LAKE MI BY 12Z TUE). THE DEFORMATION ZONE TO
EXTEND FROM SRN MN TO N-CNTRL WI...SO HIGHER QPF MAY NEED TO BE
SHIFTED A BIT TO THE NW FROM THE PREVIOUS FCST. THE MAIN FCST
ISSUE WL BE TIMING OF THE PCPN CHANGEOVER ACROSS NRN AND CNTRL WI
AS COLDER AIR GETS DRAWN INTO THE STATE. SNOW SHOULD BEGIN TO MIX
WITH RAIN DURING THE LATE EVENING N-CNTRL AND THEN OVER FAR NE/
PARTS OF CNTRL WI AFTER MIDNGT. ERN WI SHOULD REMAIN ALL LIQUID
THRU THE NGT. THERE COULD BE MINOR ACCUMULATIONS OVER N-CNTRL WI
BY DAYBREAK (GENERALLY AN INCH OR LESS) AS THE MIX DOES CHANGE TO
ALL SNOW. MIN TEMPS TO RANGE FROM THE MID 20S N-CNTRL...TO THE MID
30S NEAR LAKE MI. RAIN OR MIXED PCPN OVER ERN WI WL EVENTUALLY
SWITCH TO SNOW ON TUE AS COLDER AIR OVERSPREAD THE REGION BEHIND
THE SFC LOW WHICH THE MODELS TAKE INTO NRN SECTIONS OF LWR MI OR
LAKE HURON. ADDITIONAL MINOR ACCUMULATIONS ARE POSSIBLE...ESPECIALLY
TUE MORNING BEFORE DEEPER MOISTURE BEGINS TO PULL AWAY FROM WI
DURING THE AFTERNOON HOURS. HARD TO PUT A TOTAL ACCUMULATION NUMBER
JUST YET DUE TO THE UNKNOWN TIMING OF THE PCPN CHANGEOVER MON NGT
AND THE EXTENT OF MOISTURE OVER THE AREA ON TUE. AN EARLY ESTIMATE
WOULD BE AROUND ONE-HALF INCH OVER E-CNTRL WI TO AS MUCH AS THREE
INCHES N-CNTRL WI WHERE A LITTLE LAKE ENHANCEMENT IS POSSIBLE ON
TUE DUE TO N-NW WINDS OFF OF LAKE SUPERIOR. TEMPS ARE EXPECTED TO
BE STEADY OR SLOWLY FALL THRU THE DAY AS THE CAA TAKES OVER.
THERE CONTS TO BE SOME MODEL DISPUTE WITH RESPECT TO THE TRAILING
NRN STREAM SHORTWAVE TROF TUE NGT AS THE GFS CONTS TO CLOSE THIS
FEATURE OFF INTO AN UPR LOW OVER ND. OTHER MODELS FAVOR A MORE
PROGRESSIVE EWD MOVEMENT AND BRING THE SHORTWAVE TROF INTO THE
GREAT LAKES. HAVE FOLLOWED THE MAJORITY SOLUTION HERE WITH A SMALL
CHC OF SNOW SHWRS OR FLURRIES ACROSS THE FCST AREA. MAIN CONCERN
WL BE N-CNTRL WI WHERE PREVAILING NW WINDS AND 8H TEMPS AROUND
-12C OVER WRN LAKE SUPERIOR MAY PROVIDE LAKE EFFECT. THIS SYSTEM
DEPARTS THE REGION WED...LEAVING ONLY A MINIMAL CHC OF LAKE EFFECT
SNOW SHWRS PRIMARILY OVER VILAS CNTY. THE REST OF THE FCST AREA
SHOULD SEE PARTLY CLOUDY SKIES AS HI PRES BUILDS OVER THE UPR MS
VALLEY. MAX TEMPS BY WED TO ONLY BE A FEW DEGS ABOVE NORMAL.
A QUIET AND SOMEWHAT SEASONAL STRETCH OF WEATHER EXPECTED FOR THE
LATTER PART OF THE WORK WEEK AS THE SPRAWLING AREA OF HI PRES
SETTLES OVER THE GREAT LAKES. IT WOULD BE NICE IF THE GFS PLAYED
ALONG WITH THE OTHER MODELS/ENSEMBLES AS THE GFS RACES THE NEXT
SRN STREAM SYSTEM ACROSS THE SRN PLAINS (THU) AND OHIO/TN VALLEYS
(FRI). OBVIOUSLY...THIS SOLUTION WOULD BRING MORE CLOUDS...EVEN
PCPN CHCS TO NE WI AT WEEK`S END. HAVE DISMISSED THE GFS AS AN
OUTLIER AND KEEP THU/FRI DRY WITH TEMPS A FEW DEGS ABOVE NORMAL.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1131 AM CST SAT DEC 13 2014
VSYBS HAVE EDGE UP A BIT...MAINLY OVER THE SRN PART OF THE FCST
AREA. EXPECT VSBYS AND CIGS TO START EDGING DOWN AGAIN ARND
DUSK...PROBABLY HITTING THE DECK THIS EVENING. 18Z TAFS
CONSTRUCTED ACCORDINGLY.
&&
.HYDROLOGY...
ISSUED AT 254 AM CST SAT DEC 13 2014
THE FLOOD WARNING FOR ICE JAMS ON THE WOLF RIVER IN
KESHENA WILL CONTINUE. CALLS LATE FRIDAY SUGGESTS LITTLE CHANGE IN
THE HEIGHT OF THE ICE AND WATER. WARMER TEMPERATURES THIS WEEKEND
AND RAIN MONDAY MAY PRODUCE RUN OFF AND FLUCTUATING LEVELS THROUGH
TUESDAY. ITS POSSIBLE THE WARNING MAY BE EXTENDED THROUGH TUESDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST SUNDAY FOR WIZ005-010-018>022-
030-031-035>040-045-048>050-073-074.
DENSE FOG ADVISORY UNTIL NOON CST SUNDAY FOR WIZ011>013.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....TDH
LONG TERM......KALLAS
AVIATION.......SKOWRONSKI
HYDROLOGY......TDH
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
848 AM CST SAT DEC 13 2014
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 841 AM CST SAT DEC 13 2014
FAIRLY DENSE FOG HAS EXPANDED INTO ERN WI...WITH THE NE CORNER OF
THE STATE THE ONLY AREA WITH VSBYS ABV 1 MILE. SO WL EXPAND THE
ADVISORY INTO E-C WI.
HARD TO SEE MUCH IMPROVEMENT IN THE FG SITN DURING THE DAY AS HIGH
DWPTS /ABV 32F/ STARTING TO HEAD NEWD OVER THE SNOWPACK. BOTH THE
RAP AND HRRR VSBY PROGS KEEP FOG THROUGH THE END OF THEIR MODEL
RUNS. WL EXPAND THE ADVISORY INTO THE NE CORNER OF THE FCST AREA
STARTING AT 18Z TDA...AND EXTEND THE ADVISORY ACRS THE ENTIRE
AREA THROUGH TO 18Z TOMORROW. EVEN THAT MAY NOT BE SUFFICIENT...BUT
MAY HAVE CHEWED AWAY AT ENOUGH OF THE SNOWCOVER OVER AT LEAST THE
SWRN PART OF THE FCST AREA TO ALLOW FOR SOME IMPROVEMENT TOMORROW
AFTN.
UPDATED PRODUCT SUITE OUT ASAP.
UPDATE
ISSUED AT 552 AM CST SAT DEC 13 2014
WEB CAMS AND OBSERVATIONS SUPPORT ADDING A FEW MORE COUNTIES TO
THE DENSE FOG ADVISORY. THIS INCLUDES WINNEBAGO AND OUTAGAMIE
COUNTY.
&&
.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 254 AM CST SAT DEC 13 2014
CLOUD/FOG TRENDS ALONG WITH LIGHT PCPN WILL BE THE PRIMARY ISSUE
THROUGH SUNDAY.
EARLY THIS MORNING MUCH OF THE FORECAST AREA WAS UNDER BLANKET OF
STRATUS AND FOG. SATELLITE IMAGERY DID SHOW A SMALL POCKET OF
CLEAR SKIES OVER FAR NORTHEAST WISCONSIN NEAR IMT...WITH A MORE
SIGNIFICANT CLEAR REGION WORKING OVER SOUTHWEST WISCONSIN. THIS
CLEARING REGION MAY BRUSH WAUSHARA COUNTY EARLY THIS MORNING BUT
RAPIDLY DEVELOPING STRATUS OVER IOWA WAS QUICKLY FILLING IN THIS
HOLE. GUIDANCE SUGGESTS SKIES TO GO PARTLY CLOUDY THIS AFTERNOON
OVER CENTRAL AND EAST CENTRAL WISCONSIN. IT IS A SMALL POSSIBILITY
DUE TO THE INCREASING WINDS/GRADIENT ACROSS THE AREA. WILL CONTINUE TO
TREND TO MORE CLOUDS FOR NOW.
THIS INCREASING SOUTHWEST FLOW WAS ALSO ALLOWING INCREASING
DEWPOINTS TO WORK OVER THE SNOW COVER EARLY THIS MORNING WITH
WIDESPREAD DENSE FOG OVER WESTERN WISCONSIN STARTING TO SPILL INTO
CENTRAL AND NORTH CENTRAL WISCONSIN. WILL ISSUE A DENSE FOG
ADVISORY FOR THESE LOCATIONS THROUGH MOST OF THE MORNING HOURS AND
MONITOR FOR ANY NEEDED EXPANSION TO THE EAST.
MODELS IN GOOD AGREEMENT WITH LIGHT MEASUREABLE PCPN EVENTUALLY
SPREADING OVER THE AREA THROUGH SUNDAY. CONTINUED INCREASING
DEWPOINTS WILL FURTHER SATURATE THE BOUNDARY LAYER AND MAY
PROMPT ANOTHER DENSE FOG ADVISORY HEADLINE LATE TONIGHT INTO
SUNDAY.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 254 AM CST SAT DEC 13 2014
MEAN FLOW STILL EXPECTED TO SPLIT OVER THE ERN PACIFIC WITH A NRN
STREAM RUNNING ACROSS SRN CANADA (WITH AN OCNL DIP INTO THE NRN
TIER OF STATES) AND A SRN BRANCH RUNNING ACROSS THE SRN HALF OF
THE CONUS. AN ACTIVE START TO THE WORK WEEK AS AN INITIAL SRN
STREAM SYSTEM LIFTS NE INTO THE GREAT LAKES AND BRINGS RAIN...
THEN SNOW TO WI. WEATHER TO TURN QUIET THRU MID-WEEK WITH HI PRES
IN CONTROL...BEFORE ATTENTION TURNS TO THE NEXT SRN STREAM SYSTEM
WHICH MODELS DISAGREE WITH THE EVENTUAL TRACK FOR LATE NEXT WEEK.
TEMPS TO BE MUCH ABOVE NORMAL THRU MON WITH READINGS FALLING TO
ONLY SLIGHTLY ABOVE NORMAL FOR THE BULK OF NEXT WEEK.
SRN STREAM SYSTEM TO BE MOVING ACROSS THE CNTRL/SRN PLAINS SUNDAY
NGT AND CONTINUING TO PUMP WARM/MOIST AIR INTO WI ON S-SW WINDS.
THE DEPTH OF THE SATURATION WL CONT TO INCREASE THRU THE NGT...
THUS AREAS OF DRIZZLE MAY TURN TO RAIN CHCS AFTER MIDNGT.
OTHERWISE...A CLOUDY/MILD NGT IN STORE AND WL HAVE TO WATCH THE
FOG THICKNESS AS LOCALLY DENSE CONDITIONS/POSSIBLE HEADLINES CAN`T
BE RULED OUT. MIN TEMPS TO RANGE FROM THE UPR 30S TO LWR 40S.
THE SYSTEM IS PROGGED TO LIFT NE INTO THE MIDWEST ON MON AND WITH
MID-LEVEL FORCING/LIFT ON THE INCREASE INTO WI...WE SHOULD SEE
PCPN CHCS ALSO ON THE INCREASE. HIGHER QPF AMOUNTS SHOULD STILL BE
TO OUR SW CLOSER TO THE SYSTEM...THUS THE HIGHEST POPS HAVE BEEN
PLACED OVER CNTRL WI (LIKELY). MON TO BE THE LAST OF THE MILD DAYS
WITH MAX TEMPS TO RANGE FROM THE LWR 40S NORTH...MID TO UPR 40S
E-CNTRL WI.
MODELS HAVE FINALLY COME INTO FAIRLY GOOD AGREEMENT BY TAKING THIS
SYSTEM INTO THE WRN GREAT LAKES MON NGT (THE SFC LOW TO REACH
ROUGHLY SE WI/SRN LAKE MI BY 12Z TUE). THE DEFORMATION ZONE TO
EXTEND FROM SRN MN TO N-CNTRL WI...SO HIGHER QPF MAY NEED TO BE
SHIFTED A BIT TO THE NW FROM THE PREVIOUS FCST. THE MAIN FCST
ISSUE WL BE TIMING OF THE PCPN CHANGEOVER ACROSS NRN AND CNTRL WI
AS COLDER AIR GETS DRAWN INTO THE STATE. SNOW SHOULD BEGIN TO MIX
WITH RAIN DURING THE LATE EVENING N-CNTRL AND THEN OVER FAR NE/
PARTS OF CNTRL WI AFTER MIDNGT. ERN WI SHOULD REMAIN ALL LIQUID
THRU THE NGT. THERE COULD BE MINOR ACCUMULATIONS OVER N-CNTRL WI
BY DAYBREAK (GENERALLY AN INCH OR LESS) AS THE MIX DOES CHANGE TO
ALL SNOW. MIN TEMPS TO RANGE FROM THE MID 20S N-CNTRL...TO THE MID
30S NEAR LAKE MI. RAIN OR MIXED PCPN OVER ERN WI WL EVENTUALLY
SWITCH TO SNOW ON TUE AS COLDER AIR OVERSPREAD THE REGION BEHIND
THE SFC LOW WHICH THE MODELS TAKE INTO NRN SECTIONS OF LWR MI OR
LAKE HURON. ADDITIONAL MINOR ACCUMULATIONS ARE POSSIBLE...ESPECIALLY
TUE MORNING BEFORE DEEPER MOISTURE BEGINS TO PULL AWAY FROM WI
DURING THE AFTERNOON HOURS. HARD TO PUT A TOTAL ACCUMULATION NUMBER
JUST YET DUE TO THE UNKNOWN TIMING OF THE PCPN CHANGEOVER MON NGT
AND THE EXTENT OF MOISTURE OVER THE AREA ON TUE. AN EARLY ESTIMATE
WOULD BE AROUND ONE-HALF INCH OVER E-CNTRL WI TO AS MUCH AS THREE
INCHES N-CNTRL WI WHERE A LITTLE LAKE ENHANCEMENT IS POSSIBLE ON
TUE DUE TO N-NW WINDS OFF OF LAKE SUPERIOR. TEMPS ARE EXPECTED TO
BE STEADY OR SLOWLY FALL THRU THE DAY AS THE CAA TAKES OVER.
THERE CONTS TO BE SOME MODEL DISPUTE WITH RESPECT TO THE TRAILING
NRN STREAM SHORTWAVE TROF TUE NGT AS THE GFS CONTS TO CLOSE THIS
FEATURE OFF INTO AN UPR LOW OVER ND. OTHER MODELS FAVOR A MORE
PROGRESSIVE EWD MOVEMENT AND BRING THE SHORTWAVE TROF INTO THE
GREAT LAKES. HAVE FOLLOWED THE MAJORITY SOLUTION HERE WITH A SMALL
CHC OF SNOW SHWRS OR FLURRIES ACROSS THE FCST AREA. MAIN CONCERN
WL BE N-CNTRL WI WHERE PREVAILING NW WINDS AND 8H TEMPS AROUND
-12C OVER WRN LAKE SUPERIOR MAY PROVIDE LAKE EFFECT. THIS SYSTEM
DEPARTS THE REGION WED...LEAVING ONLY A MINIMAL CHC OF LAKE EFFECT
SNOW SHWRS PRIMARILY OVER VILAS CNTY. THE REST OF THE FCST AREA
SHOULD SEE PARTLY CLOUDY SKIES AS HI PRES BUILDS OVER THE UPR MS
VALLEY. MAX TEMPS BY WED TO ONLY BE A FEW DEGS ABOVE NORMAL.
A QUIET AND SOMEWHAT SEASONAL STRETCH OF WEATHER EXPECTED FOR THE
LATTER PART OF THE WORK WEEK AS THE SPRAWLING AREA OF HI PRES
SETTLES OVER THE GREAT LAKES. IT WOULD BE NICE IF THE GFS PLAYED
ALONG WITH THE OTHER MODELS/ENSEMBLES AS THE GFS RACES THE NEXT
SRN STREAM SYSTEM ACROSS THE SRN PLAINS (THU) AND OHIO/TN VALLEYS
(FRI). OBVIOUSLY...THIS SOLUTION WOULD BRING MORE CLOUDS...EVEN
PCPN CHCS TO NE WI AT WEEK`S END. HAVE DISMISSED THE GFS AS AN
OUTLIER AND KEEP THU/FRI DRY WITH TEMPS A FEW DEGS ABOVE NORMAL.
&&
.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 529 AM CST SAT DEC 13 2014
INCREASING MOISTURE TRAPPED UNDER A STRONG INVERSION
WILL PRODUCE WIDESPREAD LIFR/IFR CONDITIONS THIS WEEKEND. CIGS
ARE EXPECTED TO REMAIN LOW THE ENTIRE WEEKEND. DURING THE MORNING
HOURS...VSBYS DUE TO DENSE FOG WILL RANGE FROM WIDESPREAD LIFR
OVER CENTRAL AND NORTH CENTRAL WISCONSIN WISCONSIN TO VFR
CONDITIONS FAR NORTHEAST AND EASTERN WISCONSIN. ANTICIPATE LITTLE
IMPROVEMENT OVER CENTRAL AND NORTH CENTRAL WISCONSIN TODAY BEFORE
DETERIORATING AGAIN TONIGHT INTO SUNDAY. CONDITIONS OVER THE REST
OF THE AREA ALSO EXPECTED TO DETERIORATE TONIGHT INTO SUNDAY.
&&
.HYDROLOGY...
ISSUED AT 254 AM CST SAT DEC 13 2014
THE FLOOD WARNING FOR ICE JAMS ON THE WOLF RIVER IN
KESHENA WILL CONTINUE. CALLS LATE FRIDAY SUGGESTS LITTLE CHANGE IN
THE HEIGHT OF THE ICE AND WATER. WARMER TEMPERATURES THIS WEEKEND
AND RAIN MONDAY MAY PRODUCE RUN OFF AND FLUCTUATING LEVELS THROUGH
TUESDAY. ITS POSSIBLE THE WARNING MAY BE EXTENDED THROUGH TUESDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON CST SUNDAY FOR WIZ005-010-018>022-
030-031-035>040-045-048>050-073-074.
DENSE FOG ADVISORY FROM NOON TODAY TO NOON CST SUNDAY FOR
WIZ011>013.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....TDH
LONG TERM......KALLAS
AVIATION.......TDH
HYDROLOGY......TDH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1157 AM CST FRI DEC 12 2014
.UPDATE...
ISSUED AT 1157 AM CST FRI DEC 12 2014
AIR AND ROAD TEMPERATURES HAVE WARMED NEAR AND ABOVE THE FREEZING
MARK. THEREFORE...THE FREEZING FOG ADVISORY HAS BEEN ALLOWED TO
EXPIRE. AREAS OF FOG WILL PERSIST INTO THE AFTERNOON HOURS ACROSS
MUCH OF THE REGION AND THE POSSIBILITY OF VISIBILITIES REDUCED TO
A HALF MILE OR LESS AT TIMES.
UPDATE ISSUED AT 541 AM CST FRI DEC 12 2014
CALLS TO CLARK...OLMSTED AND GRANT COUNTIES HAVE REVEALED THE MIST
IS CAUSING A BIT MORE OF A PROBLEM THAN PREVIOUSLY ANTICIPATED.
REPORTS OF SLIDE OFFS IN BOTH CLARK AND OLMSTED. DOT ROAD
CONDITION MAPS DEPICT PARTIALLY COVERED IN ICE ROADS ACROSS MUCH
OF OUR FORECAST AREA...AND MOSTLY CONFINED TO OUR FORECAST AREA.
THEREFORE...HAVE ISSUED A FREEZING FOG ADVISORY FOR THE ENTIRE
FORECAST AREA. END TIME OF 16Z IS BASED ON THE ANTICIPATION OF
SOME VISIBILITY IMPROVEMENT...RISING AIR TEMPERATURES AND SOLAR
INSOLATION THROUGH THE CLOUDS WARMING ROAD TEMPERATURES.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 304 AM CST FRI DEC 12 2014
THE MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES
STARTING SATURDAY AND CONTINUING INTO SUNDAY.
THE AREA OF HIGH PRESSURE AT THE SURFACE HAS BEEN SLOWLY DRIFTING
SOUTHEAST AND IS NOW CENTERED OVER THE OHIO RIVER VALLEY WITH THE
RIDGE AXIS EXTENDING NORTH INTO WESTERN WISCONSIN. THIS HAS
ALLOWED FOR A GRADUAL INCREASE IN SOUTH TO SOUTHWEST WINDS ON THE
BACKSIDE OF THE RIDGE AXIS. THE 12.06Z RAP BUFKIT SOUNDING FOR
KRST SHOWS WINDS OF ABOUT 10 KNOTS JUST A FEW HUNDRED FEET ABOVE
THE GROUND WITH A TREND OF THESE INCREASING THROUGH THE REMAINDER
OF THE NIGHT. THIS SHOULD HELP TO BREAK THE FOG UP...WHICH HAS
BEEN THE TREND IN THE VISIBILITY OVER SOUTHEAST MINNESOTA WHERE
IT HAS IMPROVED TO A MILE AND HALF OR MORE AT ALL THE REPORTING
STATIONS IN THE DENSE FOG ADVISORY. IF THIS TREND CONTINUES...PLAN
TO CANCEL THE ADVISORY.
AFTER THAT...THE CONCERN THEN BECOMES WHEN WILL PRECIPITATION
START TO DEVELOP ACROSS THE REGION. THE CURRENT FORECAST CALLS FOR
A LOT OF DRIZZLE FOR MUCH OF THE WEEKEND...BUT HAVING A HARD TIME
SEEING THE FORCING FOR THIS DRIZZLE. THE RIDGE AXIS LOOKS TO BE
VERY SLOW MOVING AWAY FROM THE AREA...WHICH ONLY ALLOWS FOR WEAK
SOUTHWEST FLOW TO DEVELOP WITH ONLY AROUND 1C/12 HR OR LESS OF
WARM AIR ADVECTION TO BE IN THE 1000-700 MB LAYER. THIS REALLY IS
NOT ENOUGH TO PRODUCE MUCH OMEGA AND IN FACT...BOTH THE 12.00Z NAM
AND GFS BUFKIT SOUNDINGS ACTUALLY SHOW SUBSIDENCE OCCURRING UNTIL
SUNDAY NIGHT. THE GFS DOES TRY TO SHOW SOME WEAK ISENTROPIC UP
GLIDE ON THE 290K SURFACE SATURDAY AFTERNOON INTO THE EVENING
WHICH COULD BE ENOUGH TO GENERATE SOME DRIZZLE. BASED ON
THIS...WILL REMOVE THE DRIZZLE FOR LATE TONIGHT AND SATURDAY
MORNING AND LET IT GO AFTER THAT.
THE OTHER CONCERN WITH SUNDAY IS WITH TEMPERATURES. THE 11.12Z
NAEFS IS SHOWING AN AREA OF 850 TEMPERATURES BETWEEN 1 AND 2
STANDARD DEVIATIONS ABOVE NORMAL OVER THE AREA. SOUNDINGS FOR THIS
PERIOD SHOW THE INVERSION HOLDING PRETTY TIGHT...SO MOST OF THIS
WARM AIR WILL REMAIN TRAPPED ALOFT. THE 12.00Z ECMWF AND GEM MIXED
DOWN THE MOST WARM AIR AND PRODUCE LOWER 50S WEST OF THE
MISSISSIPPI RIVER WHILE THE GFS HOLDS IT IN THE LOWER TO MIDDLE
40S. WILL TRY TO HIT THE MIDDLE OF THE ROAD HERE WITH MIDDLE TO
UPPER 40S ACROSS MUCH OF THE FORECAST AREA.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 304 AM CST FRI DEC 12 2014
THE FORCING FOR WIDESPREAD PRECIPITATION PRODUCTION STARTS TO
INCREASE SUNDAY NIGHT. THE UPPER LEVEL LOW AND SHORT WAVE TROUGH
LIFTING OUT OF THE DESERT SOUTHWEST WILL BE APPROACHING THE
REGION. THIS SHOULD THEN LIFT ACROSS THE AREA MONDAY FOLLOWED
CLOSELY BY ANOTHER SHORT WAVE TROUGH COMING OUT OF THE CENTRAL
ROCKIES AND CUTTING UNDER THE NORTHERN STREAM UPPER LEVEL LOW
DROPPING SOUTH ACROSS CENTRAL CANADA. BOTH THE ECMWF AND GFS SHOW
A PERIOD OF MODERATE TO STRONG PV ADVECTION IN THE 500-300 MB
LAYER OCCURRING FROM LATE SUNDAY NIGHT THROUGH MONDAY WITH
MODERATE QG CONVERGENCE IN THE 1000-500 MB LAYER DURING THE SAME
TIME PERIOD. THE MAIN SURFACE LOW IS EXPECTED TO COME IN FROM THE
SOUTHWEST WITH THE DESERT SOUTHWEST ENERGY AND TRACK ACROSS THE
AREA MONDAY AND MONDAY NIGHT. THE BEST FRONTOGENESIS WILL BE ON
THE BACK SIDE OF THE LOW ACROSS EASTERN MINNESOTA WITH THE GFS
SHOWING THIS TO PRIMARILY BE CONFINED TO THE LOW LEVELS BUT COULD
BE RATHER STRONG. WITH THE EXPECTED INCREASE IN FORCING...STARTED
INCREASING THE PRECIPITATION CHANCES LATE SUNDAY NIGHT INTO THE 50
TO 60 PERCENT RANGE ALONG AND WEST OF THE MISSISSIPPI RIVER AND
WILL THEN HAVE 50 TO 70 PERCENT CHANCES ACROSS THE ENTIRE AREA FOR
MONDAY AND IF PRESENT MODEL TRENDS CONTINUE...EXPECT THAT THESE
WILL HAVE TO GO HIGHER WITH LATER FORECASTS. WITH THE WARM
TEMPERATURES...THE PRECIPITATION SHOULD PRIMARILY BE RAIN THROUGH
MONDAY BEFORE COLD AIR STARTS TO COME IN ONCE THE SURFACE LOW
PASSES FOR A CHANGE OVER TO LIGHT SNOW FOR MONDAY NIGHT AND
TUESDAY.
ANOTHER SYSTEM COULD POSSIBLY START TO IMPACT THE REGION FOR
THURSDAY...BUT CONFIDENCE IN THE MODELS IS PRETTY LOW BY THEN. THE
ECMWF...GFS AND 12.00Z GEM ALL SHOW DIFFERENT SOLUTIONS WITH THE
NORTHERN STREAM UPPER LEVEL LOW THAT COMES DOWN FROM CANADA WHICH
RAISES CONSIDERABLE DOUBT ON ANY ONE SOLUTION FOR LATER IN THE
WEEK. SO FOR NOW...HAVE STAYED WITH MODEL CONSENSUS WITH JUST A
VERY LOW PRECIPITATION CHANCE FOR WEDNESDAY NIGHT AND THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1157 AM CST FRI DEC 12 2014
MAIN CONCERNS THROUGH TAF PERIOD ARE LIFR/IFR AND MVFR CONDITIONS
TO PERSIST AT RST AND LSE TAF SITES. LATEST METARS ACROSS MUCH OF THE
AREA ARE REPORTING CEILING HEIGHTS IN THE LIFR/IFR RANGE AND AT
BOTH TAF SITES. SOME METARS IN NORTHEAST IOWA/SOUTHWEST WISCONSIN ARE
REPORTING MVFR CONDITIONS AND THESE CONDITIONS COULD LIFT
NORTHWARD INTO THE LSE TAF SITE. HAVE INTRODUCED A TEMPO GROUP OF
MVFR CONDITIONS AT THE LSE TAF SITE. LATE THIS AFTERNOON INTO
TONIGHT...WITH CONTINUE INCREASING NEAR SURFACE BOUNDARY LAYER
MOISTURE UNDER STRONG INVERSION. EXPECT CEILING HEIGHTS AND
POSSIBLY VISIBILITIES TO LOWER INTO THE LIFR/IFR CATEGORIES AT
BOTH RST LSE TAF SITES TONIGHT INTO SATURDAY MORNING.
&&
.CLIMATE...
ISSUED AT 541 AM CST FRI DEC 12 2014
LOOKING AHEAD TO SUNDAY...ITS WORTH NOTING THAT OUR RECORD HIGHS
ARE 52 AT ROCHESTER AND 56 AT LA CROSSE. THESE RECORDS...AS WELL
AS MANY AROUND OTHER SMALLER CITIES / SITES AROUND THE FORECAST
AREA...WERE SET IN 1998. RIGHT NOW THE FORECAST HIGHS STAY BELOW
RECORDS...BUT THERE IS SOME FORECAST GUIDANCE SUCH AS THE ECMWF
THAT SHOWS POTENTIAL TO GET CLOSE TO OR BREAK THE RECORDS.
SOMETHING TO WATCH OVER THE NEXT FEW DAYS.
WE COULD STAND A MUCH BETTER CHANCE AT BREAKING THE RECORD WARM
LOWS FOR SUNDAY. ROCHESTER IS 37 SET IN 1928 WHILE LA CROSSE IS 35
SET IN 2011. MOST LOCATIONS HAVE RECORD WARM LOWS IN THE 30S WHILE
THE FORECAST HAS LOWS IN THE UPPER 30S TO LOW 40S.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...DTJ
SHORT TERM...04
LONG TERM...04
AVIATION...DTJ
CLIMATE...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
541 AM CST FRI DEC 12 2014
.UPDATE...
ISSUED AT 541 AM CST FRI DEC 12 2014
CALLS TO CLARK...OLMSTED AND GRANT COUNTIES HAVE REVEALED THE MIST
IS CAUSING A BIT MORE OF A PROBLEM THAN PREVIOUSLY ANTICIPATED.
REPORTS OF SLIDEOFFS IN BOTH CLARK AND OLMSTED. DOT ROAD
CONDITION MAPS DEPICT PARTIALLY COVERED IN ICE ROADS ACROSS MUCH
OF OUR FORECAST AREA...AND MOSTLY CONFINED TO OUR FORECAST AREA.
THEREFORE...HAVE ISSUED A FREEZING FOG ADVISORY FOR THE ENTIRE
FORECAST AREA. END TIME OF 16Z IS BASED ON THE ANTICIPATION OF
SOME VISIBILITY IMPROVEMENT...RISING AIR TEMPERATURES AND SOLAR
INSOLATION THROUGH THE CLOUDS WARMING ROAD TEMPERATURES.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 304 AM CST FRI DEC 12 2014
THE MAIN FORECAST CONCERN IS WITH THE PRECIPITATION CHANCES
STARTING SATURDAY AND CONTINUING INTO SUNDAY.
THE AREA OF HIGH PRESSURE AT THE SURFACE HAS BEEN SLOWLY DRIFTING
SOUTHEAST AND IS NOW CENTERED OVER THE OHIO RIVER VALLEY WITH THE
RIDGE AXIS EXTENDING NORTH INTO WESTERN WISCONSIN. THIS HAS
ALLOWED FOR A GRADUAL INCREASE IN SOUTH TO SOUTHWEST WINDS ON THE
BACKSIDE OF THE RIDGE AXIS. THE 12.06Z RAP BUFKIT SOUNDING FOR
KRST SHOWS WINDS OF ABOUT 10 KNOTS JUST A FEW HUNDRED FEET ABOVE
THE GROUND WITH A TREND OF THESE INCREASING THROUGH THE REMAINDER
OF THE NIGHT. THIS SHOULD HELP TO BREAK THE FOG UP...WHICH HAS
BEEN THE TREND IN THE VISIBILITY OVER SOUTHEAST MINNESOTA WHERE
IT HAS IMPROVED TO A MILE AND HALF OR MORE AT ALL THE REPORTING
STATIONS IN THE DENSE FOG ADVISORY. IF THIS TREND CONTINUES...PLAN
TO CANCEL THE ADVISORY.
AFTER THAT...THE CONCERN THEN BECOMES WHEN WILL PRECIPITATION
START TO DEVELOP ACROSS THE REGION. THE CURRENT FORECAST CALLS FOR
A LOT OF DRIZZLE FOR MUCH OF THE WEEKEND...BUT HAVING A HARD TIME
SEEING THE FORCING FOR THIS DRIZZLE. THE RIDGE AXIS LOOKS TO BE
VERY SLOW MOVING AWAY FROM THE AREA...WHICH ONLY ALLOWS FOR WEAK
SOUTHWEST FLOW TO DEVELOP WITH ONLY AROUND 1C/12 HR OR LESS OF
WARM AIR ADVECTION TO BE IN THE 1000-700 MB LAYER. THIS REALLY IS
NOT ENOUGH TO PRODUCE MUCH OMEGA AND IN FACT...BOTH THE 12.00Z NAM
AND GFS BUFKIT SOUNDINGS ACTUALLY SHOW SUBSIDENCE OCCURRING UNTIL
SUNDAY NIGHT. THE GFS DOES TRY TO SHOW SOME WEAK ISENTROPIC UP
GLIDE ON THE 290K SURFACE SATURDAY AFTERNOON INTO THE EVENING
WHICH COULD BE ENOUGH TO GENERATE SOME DRIZZLE. BASED ON
THIS...WILL REMOVE THE DRIZZLE FOR LATE TONIGHT AND SATURDAY
MORNING AND LET IT GO AFTER THAT.
THE OTHER CONCERN WITH SUNDAY IS WITH TEMPERATURES. THE 11.12Z
NAEFS IS SHOWING AN AREA OF 850 TEMPERATURES BETWEEN 1 AND 2
STANDARD DEVIATIONS ABOVE NORMAL OVER THE AREA. SOUNDINGS FOR THIS
PERIOD SHOW THE INVERSION HOLDING PRETTY TIGHT...SO MOST OF THIS
WARM AIR WILL REMAIN TRAPPED ALOFT. THE 12.00Z ECMWF AND GEM MIXED
DOWN THE MOST WARM AIR AND PRODUCE LOWER 50S WEST OF THE
MISSISSIPPI RIVER WHILE THE GFS HOLDS IT IN THE LOWER TO MIDDLE
40S. WILL TRY TO HIT THE MIDDLE OF THE ROAD HERE WITH MIDDLE TO
UPPER 40S ACROSS MUCH OF THE FORECAST AREA.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 304 AM CST FRI DEC 12 2014
THE FORCING FOR WIDESPREADY PRECIPITATION PRODUCTION STARTS TO
INCREASE SUNDAY NIGHT. THE UPPER LEVEL LOW AND SHORT WAVE TROUGH
LIFTING OUT OF THE DESERT SOUTHWEST WILL BE APPROACHING THE
REGION. THIS SHOULD THEN LIFT ACROSS THE AREA MONDAY FOLLOWED
CLOSELY BY ANOTHER SHORT WAVE TROUGH COMING OUT OF THE CENTRAL
ROCKIES AND CUTTING UNDER THE NORTHERN STREAM UPPER LEVEL LOW
DROPPING SOUTH ACROSS CENTRAL CANADA. BOTH THE ECMWF AND GFS SHOW
A PERIOD OF MODERATE TO STRONG PV ADVECTION IN THE 500-300 MB
LAYER OCCURRING FROM LATE SUNDAY NIGHT THROUGH MONDAY WITH
MODERATE QG CONVERGENCE IN THE 1000-500 MB LAYER DURING THE SAME
TIME PERIOD. THE MAIN SURFACE LOW IS EXPECTED TO COME IN FROM THE
SOUTHWEST WITH THE DESERT SOUTHWEST ENERGY AND TRACK ACROSS THE
AREA MONDAY AND MONDAY NIGHT. THE BEST FRONTOGENESIS WILL BE ON
THE BACK SIDE OF THE LOW ACROSS EASTERN MINNESOTA WITH THE GFS
SHOWING THIS TO PRIMARILY BE CONFINED TO THE LOW LEVELS BUT COULD
BE RATHER STRONG. WITH THE EXPECTED INCREASE IN FORCING...STARTED
INCREASING THE PRECIPITATION CHANCES LATE SUNDAY NIGHT INTO THE 50
TO 60 PERCENT RANGE ALONG AND WEST OF THE MISSISSIPPI RIVER AND
WILL THEN HAVE 50 TO 70 PERCENT CHANCES ACROSS THE ENTIRE AREA FOR
MONDAY AND IF PRESENT MODEL TRENDS CONTINUE...EXPECT THAT THESE
WILL HAVE TO GO HIGHER WITH LATER FORECASTS. WITH THE WARM
TEMPERATURES...THE PRECIPITATION SHOULD PRIMARILY BE RAIN THROUGH
MONDAY BEFORE COLD AIR STARTS TO COME IN ONCE THE SURFACE LOW
PASSES FOR A CHANGE OVER TO LIGHT SNOW FOR MONDAY NIGHT AND
TUESDAY.
ANOTHER SYSTEM COULD POSSIBLY START TO IMPACT THE REGION FOR
THURSDAY...BUT CONFIDENCE IN THE MODELS IS PRETTY LOW BY THEN. THE
ECMWF...GFS AND 12.00Z GEM ALL SHOW DIFFERENT SOLUTIONS WITH THE
NORTHERN STREAM UPPER LEVEL LOW THAT COMES DOWN FROM CANADA WHICH
RAISES CONSIDERABLE DOUBT ON ANY ONE SOLUTION FOR LATER IN THE
WEEK. SO FOR NOW...HAVE STAYED WITH MODEL CONSENSUS WITH JUST A
VERY LOW PRECIPITATION CHANCE FOR WEDNESDAY NIGHT AND THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 541 AM CST FRI DEC 12 2014
LOW STRATUS PERSISTS OVER THE TAF SITES WITH MVFR CONDITIONS AT
LSE AND LIFR CONDITIONS AT RST. ADDITIONALLY...VISIBILITIES HAVE
BEEN STUCK AT MVFR AT LSE AND IFR AT RST. EXPECT THESE VISBILITIES
TO IMPROVE LATE THIS MORNING DUE TO DAYTIME HEATING...CLIMBING TO
VFR AT LSE AND MVFR AT RST. CEILINGS...ON THE OTHER HAND...MAY NOT
GO ANYWHERE AS A SOUTH TO SOUTHWEST FLOW CONTINUES TO PUMP
MOISTURE INTO THE COLDER AIRMASS IN PLACE. AS WE HEAD INTO
TONIGHT...VISIBILITIES LOOK TO FALL BACK DOWN WITH THE LOSS OF
DAYTIME HEATING...TO IFR AT RST AND MVFR AT RST. THESE COULD FALL
EVEN FURTHER AT RST...BUT CONFIDENCE IS NOT HIGH ENOUGH TO GO
LOWER THAN IFR YET.
&&
.CLIMATE...
ISSUED AT 541 AM CST FRI DEC 12 2014
LOOKING AHEAD TO SUNDAY...ITS WORTH NOTING THAT OUR RECORD HIGHS
ARE 52 AT ROCHESTER AND 56 AT LA CROSSE. THESE RECORDS...AS WELL
AS MANY AROUND OTHER SMALLER CITIES / SITES AROUND THE FORECAST
AREA...WERE SET IN 1998. RIGHT NOW THE FORECAST HIGHS STAY BELOW
RECORDS...BUT THERE IS SOME FORECAST GUIDANCE SUCH AS THE ECMWF
THAT SHOWS POTENTIAL TO GET CLOSE TO OR BREAK THE RECORDS.
SOMETHING TO WATCH OVER THE NEXT FEW DAYS.
WE COULD STAND A MUCH BETTER CHANCE AT BREAKING THE RECORD WARM
LOWS FOR SUNDAY. ROCHESTER IS 37 SET IN 1928 WHILE LA CROSSE IS 35
SET IN 2011. MOST LOCATIONS HAVE RECORD WARM LOWS IN THE 30S WHILE
THE FORECAST HAS LOWS IN THE UPPER 30S TO LOW 40S.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FREEZING FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR WIZ017-
029-032>034-041>044-053>055-061.
MN...FREEZING FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR MNZ079-
086>088-094>096.
IA...FREEZING FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR
IAZ008>011-018-019-029-030.
&&
$$
UPDATE...AJ
SHORT TERM...04
LONG TERM...04
AVIATION...AJ
CLIMATE...AJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
657 AM EST SUN DEC 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EST SUN DEC 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SPLIT FLOW PATTERN ACROSS
NORTH AMERICA WITH AN UNSEASONABLY STRONG RIDGE FROM THE MS
VALLEY INTO THE WRN GREAT LAKES DOWNSTREAM FROM A TROUGH ACROSS THE
ROCKIES. AT THE SFC..SRLY WINDS WERE INCREASING FROM THE CENTRAL
PLAINS TOWARD THE UPPER MS VALLEY AHEAD OF A TROUGH FROM CENTRAL
SOUTH DAKOTA INTO WRN NEBRASKA. THE SRLY FLOW AND LOW LEVEL MOISTURE
ADVECTION HAS PUSHED DEWPOINTS TO NEAR 40F FROM CENTRAL MN AND NW WI
TO WRN UPPER MI AND INTO THE MID 30S THROUGH CNTRL UPPER MI. A
PERSISTENT LOW STRATUS DECK HAS HELPED KEEP FOG FROM BECOMING AS
DENSE OVER UPPER MI COMPARED TO LOCATIONS OVER WI.
THERE REMAINS ONLY WEAK IF ANY FORCING FOR UPWARD MOTION OVER UPPER
MI TODAY AS THE AREA REMAINS NEAR THE MID/UPPER LEVEL RIDGE AXIS.
NEVERTHELESS...THE POTENTIAL FOR DRIZZLE SPREADING ACROSS THE AREA
REMAINS AS SOME WEAK UPWARD MOTION IS EXPECTED ABOVE THE THICKENING
LOW LEVEL MOISTURE AHEAD OF THE TROUGH SLIDING INTO THE UPPER MS
VALLEY. DRIZZLE CHANCES WILL INCREASE TOWARD EVENING AS AN AREA OF
290K ISENTROPIC ASCENT IS FORECAST TO MOVE THROUGH UPPER MI...PER
NAM/GFS. IN ADDITION...MELTING SNOW WILL ADD ADDITIONAL MOISTURE TO
SUPPORT DEVELOPMENT OF AREAS OF DENSE FOG. HOWEVER...DIURNAL WARMING
SHOULD BE JUST ENOUGH TO REDUCE THE RISK FOR MORE WIDESPREAD DENSE
FOG. TONIGHT...DENSE FOG WILL BE A BETTER POSSIBILITY WITH DIURNAL
COOING AS DEWPOINTS INTO THE UPPER 30S PREVAIL ACROSS THE AREA. THE
THE POTENTIAL FOR ACCUMULATING PCPN WILL INCREASE LATE TONIGHT OVER
THE WEST WITH DEEPER MOISTURE ARRIVING AHEAD OF THE SFC TROUGH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 257 AM EST SUN DEC 14 2014
AFTER A WARM START TO THE LONG TERM PERIOD...A RETURN TO MORE
NORMAL MID DECEMBER TEMPERATURES IS IN STORE FOR TUESDAY AND
CONTINUING THROUGH MUCH OF THE REST OF THE WORK WEEK. ON MONDAY
MORNING...THE ANOMALOUS UPPER RIDGE WILL BE LOCATED OVER THE LOWER
GREAT LAKES REGION AND QUICKLY SHIFTING EAST INTO THE NEW ENGLAND
STATES. MEANWHILE...TWO SHORTWAVES WILL BE NEARING THE AREA AND
WILL BE THE FOCUS FOR THE FIRST HALF OF THE WORK WEEK. FIRST...THE
SOUTHERN STREAM SHORTWAVE WILL BE LOCATED IN EASTERN KANSAS AT 12Z
MONDAY AND WILL BE DRIVING THE 1001MB SURFACE LOW LOCATED IN NEARLY
THE SAME LOCATION. FROM THAT SURFACE LOW...A 1006MB TROUGH WILL
EXTEND NORTHEAST THROUGH EASTERN MINNESOTA AND INTO WESTERN LAKE
SUPERIOR. AT THAT SAME TIME...A SECONDARY SHORTWAVE WILL BE DIVING
SOUTHEAST THROUGH MANITOBA. AS THE SHORTWAVE AND SURFACE LOW LIFT
NORTHEAST TOWARDS CHICAGO BY MONDAY EVENING...THE ELONGATED TROUGH
WILL SLOWLY SHIFT EAST OUT OF WESTERN LAKE SUPERIOR AND INTO THE
WESTERN U.P. AHEAD OF THE TROUGH...THE WARM/MOIST LOW LEVEL AIR
WILL CONTINUE TO PRODUCE LOW CLOUDS...DRIZZLE...AND FOG (ALTHOUGH
THERE COULD BE PERIODS OF LIGHT RAIN SHOWERS UNDER THE WEAK WARM AIR
ADVECTION AND DEEPER MOISTURE NEAR THE TROUGH AXIS). SURFACE
TEMPERATURES ON MONDAY WILL LIKELY BE FAIRLY STEADY IN THE UPPER
30S AND LOWER 40S.
HEADING INTO MONDAY NIGHT...THE SURFACE LOW AND SOUTHERN STREAM
SHORTWAVE WILL BE SLIDING INTO LOWER MICHIGAN...WHILE THE NORTHERN
STREAM SHORTWAVE BECOMES CLOSE ENOUGH TO START INTERACTING WITH
SOUTHERN SHORTWAVE. THIS WILL HELP SHIFT THE SURFACE AND LOW LEVEL
TROUGH EAST ACROSS UPPER MICHIGAN THROUGH THE NIGHT...AND BRING
COLDER LOW LEVEL AIR INTO THE AREA. OVERALL...MODELS ARE FAIRLY
CONSISTENT IN THE IDEA OF THAT COLD AIR SWITCHING THE RAIN TO SNOW
FROM NORTHWEST TO SOUTHEAST MONDAY NIGHT INTO TUESDAY MORNING.
FIRST...HAPPENING IN THE KIWD/KCMX AREA BETWEEN 02-06Z TUESDAY AND
THEN KSAW/KIMT AROUND 09Z AND AREAS OVER THE SOUTHEAST BY 18Z
TUESDAY. WITH THOSE SHORTWAVE STARTING TO INTERACT MONDAY
NIGHT...AIDING THE TIGHTENING LOW-MID LEVEL FGEN...WOULD EXPECT A
PERIOD OF MODERATE PRECIPITATION OVER WESTERN LAKE SUPERIOR AND
WESTERN UPPER MICHIGAN ON MONDAY NIGHT. SNOWFALL AMOUNTS FOR THAT
PERIOD WILL LIKELY DEPEND ON THE TIMING OF THE CHANGE OVER...BUT
WITH THE GOING TIMING WOULD EXPECT TO SEE 1-3IN FROM HERMAN TO
WATERSMEET AND WEST BY DAYBREAK TUESDAY. FARTHER EAST...THAT
DELAYED ARRIVAL OF THE COLDER AIR WILL KEEP MORE OF THE
PRECIPITATION AS RAIN BEFORE SWITCHING TO SNOW. WHEN FACTORING IN
ADDITIONAL SNOW FOR TUESDAY...MAY NEED AN ADVISORY FOR THOSE AREAS
OVER THE WEST AND WILL CONTINUE TO INCLUDE MODERATE SNOWFALL MENTION
IN THE HWO.
HEADING INTO TUESDAY...THE SURFACE LOW AND SHORTWAVE WILL SHIFT EAST
THROUGH THE LOWER GREAT LAKES AND REDUCE THE DIRECT INTERACTION OF
IT WITH THE SECONDARY SHORTWAVE NOW SLIDING SOUTH THROUGH WESTERN
LAKE SUPERIOR AND THE MINNESOTA ARROWHEAD. WHILE THIS WILL LIKELY
WEAKEN THE SYNOPTICLY FORCED PRECIPITATION...THE COLDER AIR SURGING
OVER LAKE SUPERIOR ON TUESDAY (850MB TEMPS FALLING TO AROUND -14C
OVER THE WESTERN LAKE) SHOULD LEAD TO A TRANSITION TO LAKE
ENHANCED/EFFECT SNOW OVER THE WEST INITIALLY AND THEN SHIFTING EAST
ACROSS THE REST OF THE AREA BY EVENING. CONFIDENCE DOES BEGIN TO
WAVER SOME ON TUESDAY AND CONTINUE INTO WEDNESDAY AS THE TWO
SHORTWAVE INTERACT WITH EACH OTHER OVER THE GREAT LAKES REGION.
THIS LEADS TO DIFFERENCES IN THE EXACT MODEL SOLUTIONS...BUT THE
GENERAL IDEA IS FOR THE SURFACE LOW TO CONTINUE EAST...LEAVING A
TROUGH STRETCHED WEST-NORTHWEST ACROSS LAKE SUPERIOR ON TUESDAY
AFTERNOON/EVENING UNTIL THE TRAILING SHORTWAVE CAN SLIDE IT SOUTH
WEDNESDAY. THE 00Z GFS DOES DIFFER FROM THIS IDEA AND LINGERS THE
TROUGH OVER THE UPPER GREAT LAKES UNTIL THURSDAY MORNING...WHILE THE
00Z ECMWF CAME IN A LITTLE SLOWER BUT NOT AS DELAYED AS THE GFS.
WILL FOLLOW THE GENERAL CONSENSUS AT THIS POINT AND HAVE IT MOVING
SOUTH ON TUESDAY NIGHT INTO WEDNESDAY. THEREFORE...SHOULD SEE A
PERIOD OF NORTHERLY FLOW LAKE EFFECT SPREADING ACROSS THE AREA ON
TUESDAY INTO TUESDAY NIGHT FROM WEST TO EAST AND CONTINUING INTO
WEDNESDAY. UNTIL THE COLDER AIR CAN MOVE INTO THE AREA LATER
TUESDAY AFTERNOON AND NIGHT...EXPECT THE LAKE ENHANCED PRECIPITATION
INTENSITY TO BE LIMITED TO THE WEST HALF AND WHERE IT SNOWS THE
RATIOS WILL BE ON THE LOW END (AROUND 12-1). AS THAT COLDER AIR
MOVES IN...THE CLOUD LAYER WILL NOSE INTO THE DGZ AND INCREASE THE
RATIOS...BUT THE AREA WILL ALSO START TO SEE THE AFFECT OF THE HIGH
BUILDING SOUTH INTO SOUTHERN CANADA AND THE NORTHERN PLAINS. THAT
WILL STRENGTHEN THE INVERSION AROUND 5KFT AND HELP LIMIT THE
STRENGTH OF THE LAKE EFFECT PRECIPITATION. WHILE MUCH OF THE
FORECAST DEPENDS ON THE TIMING OF THAT SURFACE TROUGH DROPPING
ACROSS THE AREA...STILL WOULD EXPECT MANY LOCATIONS IN THE NORTHERLY
WIND SNOW BELTS TO SEE A COUPLE TO SEVERAL INCHES OF LAKE
ENHANCED/EFFECT SNOW TUESDAY AFTERNOON INTO WEDNESDAY. WILL
ALSO HIGHLIGHT THIS POTENTIAL IN THE HWO AS SOME AREAS MAY SEE
ADVISORY SNOWFALL.
BEHIND THE SURFACE TROUGH...EXPECT THE LAKE EFFECT TO DIMINISH
WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING AS THE AREA OF HIGH
PRESSURE BEGINS TO SLIDE SOUTHEAST INTO THE UPPER GREAT LAKES
REGION. WARMING TEMPERATURES ALOFT WILL ARRIVE WITH UPPER RIDGE AND
LEAD TO A QUIET END TO THE WORK WEEK AND LIKELY INTO NEXT WEEKEND.
MODELS ARE FAIRLY CONSISTENT ON THE HIGH REMAINING OVER THE UPPER
GREAT LAKES REGION THROUGH THIS PERIOD. AS FOR TEMPERATURES...EXPECT
HIGHS IN THE MID-UPPER 20S FOR THE END OF THE WORK WEEK THAT MAY TRY
TO NOSE INTO THE LOWER 30S FOR NEXT WEEKEND (WHICH WOULD BE AROUND 5
DEGREES ABOVE NORMAL FOR THAT TIME OF DECEMBER).
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 656 AM EST SUN DEC 14 2014
WITH THE ARRIVAL OF MOISTER LOW LEVEL AIR OVER MELTING SNOW...EXPECT
CONDITIONS AT SAW/CMX TO REMAIN IN THE LIFR RANGE MUCH OF THE TIME.
THE BEST CHANCE FOR SOME VLIFR CONDITIONS WILL BE AT CMX AND SAW WITH
A MORE FAVORABLE WIND DIRECTION. DOWNSLOPE WIND COMPONENT AT IWD THAT
HAS BROUGHT CIGS UP TO MVFR SHOULD GIVE WAY TO IFR CIGS BY THIS
AFTERNOON WITH THE INFLUX OF ADDITIONAL MOISTURE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 511 AM EST SUN DEC 14 2014
A RIDGE ACROSS THE UPPER GREAT LAKES WILL SLOWLY SHIFT TO THE LOWER
GREAT LAKES SUNDAY INTO MONDAY. LOOK FOR AN ELONGATED AREA OF LOW
PRESSURE ACROSS THE PLAINS STATES SUNDAY MORNING TO PUSH ACROSS LAKE
SUPERIOR LATE SUNDAY NIGHT INTO MONDAY...AS THE S END OF THE TROUGH
DEEPENS ACROSS IOWA ON MONDAY. THE LOW WILL PUSH ACROSS LOWER
MICHIGAN ON TUESDAY...AND EXIT ACROSS THE LOWER GREAT LAKES TUESDAY
NIGHT. A TIGHTENING GRADIENT BEHIND THE LOW PRES SYSTEM LATE MONDAY
NIGHT INTO TUESDAY IS EXPECTED TO BRING NORTH WINDS GUSTING TO 30
KNOTS WITH A FEW GALE FORCE GUSTS TO 35 KNOTS.
WINDS WILL DIMINISH FROM WED INTO WED NIGHT AS THE LOW MOVES AWAY
AND HIGH PRESSURE HIGH PRESSURE BUILDS TOWARD THE WRN LAKES FROM THE
PLAINS. WINDS WILL THEN REMAIN AT OR BELOW 20 KNOTS THU AS THE HIGH
SETTLES OVER THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
513 AM EST SUN DEC 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EST SUN DEC 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SPLIT FLOW PATTERN ACROSS
NORTH AMERICA WITH AN UNSEASONABLY STRONG RIDGE FROM THE MS
VALLEY INTO THE WRN GREAT LAKES DOWNSTREAM FROM A TROUGH ACROSS THE
ROCKIES. AT THE SFC..SRLY WINDS WERE INCREASING FROM THE CENTRAL
PLAINS TOWARD THE UPPER MS VALLEY AHEAD OF A TROUGH FROM CENTRAL
SOUTH DAKOTA INTO WRN NEBRASKA. THE SRLY FLOW AND LOW LEVEL MOISTURE
ADVECTION HAS PUSHED DEWPOINTS TO NEAR 40F FROM CENTRAL MN AND NW WI
TO WRN UPPER MI AND INTO THE MID 30S THROUGH CNTRL UPPER MI. A
PERSISTENT LOW STRATUS DECK HAS HELPED KEEP FOG FROM BECOMING AS
DENSE OVER UPPER MI COMPARED TO LOCATIONS OVER WI.
THERE REMAINS ONLY WEAK IF ANY FORCING FOR UPWARD MOTION OVER UPPER
MI TODAY AS THE AREA REMAINS NEAR THE MID/UPPER LEVEL RIDGE AXIS.
NEVERTHELESS...THE POTENTIAL FOR DRIZZLE SPREADING ACROSS THE AREA
REMAINS AS SOME WEAK UPWARD MOTION IS EXPECTED ABOVE THE THICKENING
LOW LEVEL MOISTURE AHEAD OF THE TROUGH SLIDING INTO THE UPPER MS
VALLEY. DRIZZLE CHANCES WILL INCREASE TOWARD EVENING AS AN AREA OF
290K ISENTROPIC ASCENT IS FORECAST TO MOVE THROUGH UPPER MI...PER
NAM/GFS. IN ADDITION...MELTING SNOW WILL ADD ADDITIONAL MOISTURE TO
SUPPORT DEVELOPMENT OF AREAS OF DENSE FOG. HOWEVER...DIURNAL WARMING
SHOULD BE JUST ENOUGH TO REDUCE THE RISK FOR MORE WIDESPREAD DENSE
FOG. TONIGHT...DENSE FOG WILL BE A BETTER POSSIBILITY WITH DIURNAL
COOING AS DEWPOINTS INTO THE UPPER 30S PREVAIL ACROSS THE AREA. THE
THE POTENTIAL FOR ACCUMULATING PCPN WILL INCREASE LATE TONIGHT OVER
THE WEST WITH DEEPER MOISTURE ARRIVING AHEAD OF THE SFC TROUGH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 257 AM EST SUN DEC 14 2014
AFTER A WARM START TO THE LONG TERM PERIOD...A RETURN TO MORE
NORMAL MID DECEMBER TEMPERATURES IS IN STORE FOR TUESDAY AND
CONTINUING THROUGH MUCH OF THE REST OF THE WORK WEEK. ON MONDAY
MORNING...THE ANOMALOUS UPPER RIDGE WILL BE LOCATED OVER THE LOWER
GREAT LAKES REGION AND QUICKLY SHIFTING EAST INTO THE NEW ENGLAND
STATES. MEANWHILE...TWO SHORTWAVES WILL BE NEARING THE AREA AND
WILL BE THE FOCUS FOR THE FIRST HALF OF THE WORK WEEK. FIRST...THE
SOUTHERN STREAM SHORTWAVE WILL BE LOCATED IN EASTERN KANSAS AT 12Z
MONDAY AND WILL BE DRIVING THE 1001MB SURFACE LOW LOCATED IN NEARLY
THE SAME LOCATION. FROM THAT SURFACE LOW...A 1006MB TROUGH WILL
EXTEND NORTHEAST THROUGH EASTERN MINNESOTA AND INTO WESTERN LAKE
SUPERIOR. AT THAT SAME TIME...A SECONDARY SHORTWAVE WILL BE DIVING
SOUTHEAST THROUGH MANITOBA. AS THE SHORTWAVE AND SURFACE LOW LIFT
NORTHEAST TOWARDS CHICAGO BY MONDAY EVENING...THE ELONGATED TROUGH
WILL SLOWLY SHIFT EAST OUT OF WESTERN LAKE SUPERIOR AND INTO THE
WESTERN U.P. AHEAD OF THE TROUGH...THE WARM/MOIST LOW LEVEL AIR
WILL CONTINUE TO PRODUCE LOW CLOUDS...DRIZZLE...AND FOG (ALTHOUGH
THERE COULD BE PERIODS OF LIGHT RAIN SHOWERS UNDER THE WEAK WARM AIR
ADVECTION AND DEEPER MOISTURE NEAR THE TROUGH AXIS). SURFACE
TEMPERATURES ON MONDAY WILL LIKELY BE FAIRLY STEADY IN THE UPPER
30S AND LOWER 40S.
HEADING INTO MONDAY NIGHT...THE SURFACE LOW AND SOUTHERN STREAM
SHORTWAVE WILL BE SLIDING INTO LOWER MICHIGAN...WHILE THE NORTHERN
STREAM SHORTWAVE BECOMES CLOSE ENOUGH TO START INTERACTING WITH
SOUTHERN SHORTWAVE. THIS WILL HELP SHIFT THE SURFACE AND LOW LEVEL
TROUGH EAST ACROSS UPPER MICHIGAN THROUGH THE NIGHT...AND BRING
COLDER LOW LEVEL AIR INTO THE AREA. OVERALL...MODELS ARE FAIRLY
CONSISTENT IN THE IDEA OF THAT COLD AIR SWITCHING THE RAIN TO SNOW
FROM NORTHWEST TO SOUTHEAST MONDAY NIGHT INTO TUESDAY MORNING.
FIRST...HAPPENING IN THE KIWD/KCMX AREA BETWEEN 02-06Z TUESDAY AND
THEN KSAW/KIMT AROUND 09Z AND AREAS OVER THE SOUTHEAST BY 18Z
TUESDAY. WITH THOSE SHORTWAVE STARTING TO INTERACT MONDAY
NIGHT...AIDING THE TIGHTENING LOW-MID LEVEL FGEN...WOULD EXPECT A
PERIOD OF MODERATE PRECIPITATION OVER WESTERN LAKE SUPERIOR AND
WESTERN UPPER MICHIGAN ON MONDAY NIGHT. SNOWFALL AMOUNTS FOR THAT
PERIOD WILL LIKELY DEPEND ON THE TIMING OF THE CHANGE OVER...BUT
WITH THE GOING TIMING WOULD EXPECT TO SEE 1-3IN FROM HERMAN TO
WATERSMEET AND WEST BY DAYBREAK TUESDAY. FARTHER EAST...THAT
DELAYED ARRIVAL OF THE COLDER AIR WILL KEEP MORE OF THE
PRECIPITATION AS RAIN BEFORE SWITCHING TO SNOW. WHEN FACTORING IN
ADDITIONAL SNOW FOR TUESDAY...MAY NEED AN ADVISORY FOR THOSE AREAS
OVER THE WEST AND WILL CONTINUE TO INCLUDE MODERATE SNOWFALL MENTION
IN THE HWO.
HEADING INTO TUESDAY...THE SURFACE LOW AND SHORTWAVE WILL SHIFT EAST
THROUGH THE LOWER GREAT LAKES AND REDUCE THE DIRECT INTERACTION OF
IT WITH THE SECONDARY SHORTWAVE NOW SLIDING SOUTH THROUGH WESTERN
LAKE SUPERIOR AND THE MINNESOTA ARROWHEAD. WHILE THIS WILL LIKELY
WEAKEN THE SYNOPTICLY FORCED PRECIPITATION...THE COLDER AIR SURGING
OVER LAKE SUPERIOR ON TUESDAY (850MB TEMPS FALLING TO AROUND -14C
OVER THE WESTERN LAKE) SHOULD LEAD TO A TRANSITION TO LAKE
ENHANCED/EFFECT SNOW OVER THE WEST INITIALLY AND THEN SHIFTING EAST
ACROSS THE REST OF THE AREA BY EVENING. CONFIDENCE DOES BEGIN TO
WAVER SOME ON TUESDAY AND CONTINUE INTO WEDNESDAY AS THE TWO
SHORTWAVE INTERACT WITH EACH OTHER OVER THE GREAT LAKES REGION.
THIS LEADS TO DIFFERENCES IN THE EXACT MODEL SOLUTIONS...BUT THE
GENERAL IDEA IS FOR THE SURFACE LOW TO CONTINUE EAST...LEAVING A
TROUGH STRETCHED WEST-NORTHWEST ACROSS LAKE SUPERIOR ON TUESDAY
AFTERNOON/EVENING UNTIL THE TRAILING SHORTWAVE CAN SLIDE IT SOUTH
WEDNESDAY. THE 00Z GFS DOES DIFFER FROM THIS IDEA AND LINGERS THE
TROUGH OVER THE UPPER GREAT LAKES UNTIL THURSDAY MORNING...WHILE THE
00Z ECMWF CAME IN A LITTLE SLOWER BUT NOT AS DELAYED AS THE GFS.
WILL FOLLOW THE GENERAL CONSENSUS AT THIS POINT AND HAVE IT MOVING
SOUTH ON TUESDAY NIGHT INTO WEDNESDAY. THEREFORE...SHOULD SEE A
PERIOD OF NORTHERLY FLOW LAKE EFFECT SPREADING ACROSS THE AREA ON
TUESDAY INTO TUESDAY NIGHT FROM WEST TO EAST AND CONTINUING INTO
WEDNESDAY. UNTIL THE COLDER AIR CAN MOVE INTO THE AREA LATER
TUESDAY AFTERNOON AND NIGHT...EXPECT THE LAKE ENHANCED PRECIPITATION
INTENSITY TO BE LIMITED TO THE WEST HALF AND WHERE IT SNOWS THE
RATIOS WILL BE ON THE LOW END (AROUND 12-1). AS THAT COLDER AIR
MOVES IN...THE CLOUD LAYER WILL NOSE INTO THE DGZ AND INCREASE THE
RATIOS...BUT THE AREA WILL ALSO START TO SEE THE AFFECT OF THE HIGH
BUILDING SOUTH INTO SOUTHERN CANADA AND THE NORTHERN PLAINS. THAT
WILL STRENGTHEN THE INVERSION AROUND 5KFT AND HELP LIMIT THE
STRENGTH OF THE LAKE EFFECT PRECIPITATION. WHILE MUCH OF THE
FORECAST DEPENDS ON THE TIMING OF THAT SURFACE TROUGH DROPPING
ACROSS THE AREA...STILL WOULD EXPECT MANY LOCATIONS IN THE NORTHERLY
WIND SNOW BELTS TO SEE A COUPLE TO SEVERAL INCHES OF LAKE
ENHANCED/EFFECT SNOW TUESDAY AFTERNOON INTO WEDNESDAY. WILL
ALSO HIGHLIGHT THIS POTENTIAL IN THE HWO AS SOME AREAS MAY SEE
ADVISORY SNOWFALL.
BEHIND THE SURFACE TROUGH...EXPECT THE LAKE EFFECT TO DIMINISH
WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING AS THE AREA OF HIGH
PRESSURE BEGINS TO SLIDE SOUTHEAST INTO THE UPPER GREAT LAKES
REGION. WARMING TEMPERATURES ALOFT WILL ARRIVE WITH UPPER RIDGE AND
LEAD TO A QUIET END TO THE WORK WEEK AND LIKELY INTO NEXT WEEKEND.
MODELS ARE FAIRLY CONSISTENT ON THE HIGH REMAINING OVER THE UPPER
GREAT LAKES REGION THROUGH THIS PERIOD. AS FOR TEMPERATURES...EXPECT
HIGHS IN THE MID-UPPER 20S FOR THE END OF THE WORK WEEK THAT MAY TRY
TO NOSE INTO THE LOWER 30S FOR NEXT WEEKEND (WHICH WOULD BE AROUND 5
DEGREES ABOVE NORMAL FOR THAT TIME OF DECEMBER).
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY MORNING) ISSUED AT
513 AM EST SUN DEC 14 2014
IN THE PRESENCE OF DIURNAL COOLING...SLOWLY DIMINISHING SSW WINDS
AND THE ARRIVAL OF MOISTER LLVL AIR OVER MELTING SN PACK...EXPECT
CONDITIONS AT ALL 3 SITES TO FALL INTO THE LIFR RANGE MUCH OF THE
TIME THRU THIS MRNG. THE BEST CHANCE FOR SOME VLIFR CONDITIONS WL BE
AT CMX AND SAW LATER THIS MRNG WITH A MORE FAVORABLE WIND DIRECTION.
DOWNSLOPE WIND COMPONENT AT IWD WL LIMIT THE POTENTIAL FOR THIS
CONDITION AT THAT SITE. THERE WL BE ONLY A SLOW RECOVERY TO IFR
CONDITIONS WITH CONTINUED INFLUX OF MORE LLVL MSTR AND LO SUN ANGLE
HINDERING A MORE SGNFT IMPROVEMENT. NOT OUT OF THE QUESTION A
STRENGTHENING DOWNSLOPE SW FLOW IN ADVANCE OF AN APRCHG LO PRES
COULD BRING SOME MVFR WX TO IWD LATE IN THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 511 AM EST SUN DEC 14 2014
A RIDGE ACROSS THE UPPER GREAT LAKES WILL SLOWLY SHIFT TO THE LOWER
GREAT LAKES SUNDAY INTO MONDAY. LOOK FOR AN ELONGATED AREA OF LOW
PRESSURE ACROSS THE PLAINS STATES SUNDAY MORNING TO PUSH ACROSS LAKE
SUPERIOR LATE SUNDAY NIGHT INTO MONDAY...AS THE S END OF THE TROUGH
DEEPENS ACROSS IOWA ON MONDAY. THE LOW WILL PUSH ACROSS LOWER
MICHIGAN ON TUESDAY...AND EXIT ACROSS THE LOWER GREAT LAKES TUESDAY
NIGHT. A TIGHTENING GRADIENT BEHIND THE LOW PRES SYSTEM LATE MONDAY
NIGHT INTO TUESDAY IS EXPECTED TO BRING NORTH WINDS GUSTING TO 30
KNOTS WITH A FEW GALE FORCE GUSTS TO 35 KNOTS.
WINDS WILL DIMINISH FROM WED INTO WED NIGHT AS THE LOW MOVES AWAY
AND HIGH PRESSURE HIGH PRESSURE BUILDS TOWARD THE WRN LAKES FROM THE
PLAINS. WINDS WILL THEN REMAIN AT OR BELOW 20 KNOTS THU AS THE HIGH
SETTLES OVER THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
512 AM EST SUN DEC 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EST SUN DEC 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SPLIT FLOW PATTERN ACROSS
NORTH AMERICA WITH AN UNSEASONABLY STRONG RIDGE FROM THE MS
VALLEY INTO THE WRN GREAT LAKES DOWNSTREAM FROM A TROUGH ACROSS THE
ROCKIES. AT THE SFC..SRLY WINDS WERE INCREASING FROM THE CENTRAL
PLAINS TOWARD THE UPPER MS VALLEY AHEAD OF A TROUGH FROM CENTRAL
SOUTH DAKOTA INTO WRN NEBRASKA. THE SRLY FLOW AND LOW LEVEL MOISTURE
ADVECTION HAS PUSHED DEWPOINTS TO NEAR 40F FROM CENTRAL MN AND NW WI
TO WRN UPPER MI AND INTO THE MID 30S THROUGH CNTRL UPPER MI. A
PERSISTENT LOW STRATUS DECK HAS HELPED KEEP FOG FROM BECOMING AS
DENSE OVER UPPER MI COMPARED TO LOCATIONS OVER WI.
THERE REMAINS ONLY WEAK IF ANY FORCING FOR UPWARD MOTION OVER UPPER
MI TODAY AS THE AREA REMAINS NEAR THE MID/UPPER LEVEL RIDGE AXIS.
NEVERTHELESS...THE POTENTIAL FOR DRIZZLE SPREADING ACROSS THE AREA
REMAINS AS SOME WEAK UPWARD MOTION IS EXPECTED ABOVE THE THICKENING
LOW LEVEL MOISTURE AHEAD OF THE TROUGH SLIDING INTO THE UPPER MS
VALLEY. DRIZZLE CHANCES WILL INCREASE TOWARD EVENING AS AN AREA OF
290K ISENTROPIC ASCENT IS FORECAST TO MOVE THROUGH UPPER MI...PER
NAM/GFS. IN ADDITION...MELTING SNOW WILL ADD ADDITIONAL MOISTURE TO
SUPPORT DEVELOPMENT OF AREAS OF DENSE FOG. HOWEVER...DIURNAL WARMING
SHOULD BE JUST ENOUGH TO REDUCE THE RISK FOR MORE WIDESPREAD DENSE
FOG. TONIGHT...DENSE FOG WILL BE A BETTER POSSIBILITY WITH DIURNAL
COOING AS DEWPOINTS INTO THE UPPER 30S PREVAIL ACROSS THE AREA. THE
THE POTENTIAL FOR ACCUMULATING PCPN WILL INCREASE LATE TONIGHT OVER
THE WEST WITH DEEPER MOISTURE ARRIVING AHEAD OF THE SFC TROUGH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 257 AM EST SUN DEC 14 2014
AFTER A WARM START TO THE LONG TERM PERIOD...A RETURN TO MORE
NORMAL MID DECEMBER TEMPERATURES IS IN STORE FOR TUESDAY AND
CONTINUING THROUGH MUCH OF THE REST OF THE WORK WEEK. ON MONDAY
MORNING...THE ANOMALOUS UPPER RIDGE WILL BE LOCATED OVER THE LOWER
GREAT LAKES REGION AND QUICKLY SHIFTING EAST INTO THE NEW ENGLAND
STATES. MEANWHILE...TWO SHORTWAVES WILL BE NEARING THE AREA AND
WILL BE THE FOCUS FOR THE FIRST HALF OF THE WORK WEEK. FIRST...THE
SOUTHERN STREAM SHORTWAVE WILL BE LOCATED IN EASTERN KANSAS AT 12Z
MONDAY AND WILL BE DRIVING THE 1001MB SURFACE LOW LOCATED IN NEARLY
THE SAME LOCATION. FROM THAT SURFACE LOW...A 1006MB TROUGH WILL
EXTEND NORTHEAST THROUGH EASTERN MINNESOTA AND INTO WESTERN LAKE
SUPERIOR. AT THAT SAME TIME...A SECONDARY SHORTWAVE WILL BE DIVING
SOUTHEAST THROUGH MANITOBA. AS THE SHORTWAVE AND SURFACE LOW LIFT
NORTHEAST TOWARDS CHICAGO BY MONDAY EVENING...THE ELONGATED TROUGH
WILL SLOWLY SHIFT EAST OUT OF WESTERN LAKE SUPERIOR AND INTO THE
WESTERN U.P. AHEAD OF THE TROUGH...THE WARM/MOIST LOW LEVEL AIR
WILL CONTINUE TO PRODUCE LOW CLOUDS...DRIZZLE...AND FOG (ALTHOUGH
THERE COULD BE PERIODS OF LIGHT RAIN SHOWERS UNDER THE WEAK WARM AIR
ADVECTION AND DEEPER MOISTURE NEAR THE TROUGH AXIS). SURFACE
TEMPERATURES ON MONDAY WILL LIKELY BE FAIRLY STEADY IN THE UPPER
30S AND LOWER 40S.
HEADING INTO MONDAY NIGHT...THE SURFACE LOW AND SOUTHERN STREAM
SHORTWAVE WILL BE SLIDING INTO LOWER MICHIGAN...WHILE THE NORTHERN
STREAM SHORTWAVE BECOMES CLOSE ENOUGH TO START INTERACTING WITH
SOUTHERN SHORTWAVE. THIS WILL HELP SHIFT THE SURFACE AND LOW LEVEL
TROUGH EAST ACROSS UPPER MICHIGAN THROUGH THE NIGHT...AND BRING
COLDER LOW LEVEL AIR INTO THE AREA. OVERALL...MODELS ARE FAIRLY
CONSISTENT IN THE IDEA OF THAT COLD AIR SWITCHING THE RAIN TO SNOW
FROM NORTHWEST TO SOUTHEAST MONDAY NIGHT INTO TUESDAY MORNING.
FIRST...HAPPENING IN THE KIWD/KCMX AREA BETWEEN 02-06Z TUESDAY AND
THEN KSAW/KIMT AROUND 09Z AND AREAS OVER THE SOUTHEAST BY 18Z
TUESDAY. WITH THOSE SHORTWAVE STARTING TO INTERACT MONDAY
NIGHT...AIDING THE TIGHTENING LOW-MID LEVEL FGEN...WOULD EXPECT A
PERIOD OF MODERATE PRECIPITATION OVER WESTERN LAKE SUPERIOR AND
WESTERN UPPER MICHIGAN ON MONDAY NIGHT. SNOWFALL AMOUNTS FOR THAT
PERIOD WILL LIKELY DEPEND ON THE TIMING OF THE CHANGE OVER...BUT
WITH THE GOING TIMING WOULD EXPECT TO SEE 1-3IN FROM HERMAN TO
WATERSMEET AND WEST BY DAYBREAK TUESDAY. FARTHER EAST...THAT
DELAYED ARRIVAL OF THE COLDER AIR WILL KEEP MORE OF THE
PRECIPITATION AS RAIN BEFORE SWITCHING TO SNOW. WHEN FACTORING IN
ADDITIONAL SNOW FOR TUESDAY...MAY NEED AN ADVISORY FOR THOSE AREAS
OVER THE WEST AND WILL CONTINUE TO INCLUDE MODERATE SNOWFALL MENTION
IN THE HWO.
HEADING INTO TUESDAY...THE SURFACE LOW AND SHORTWAVE WILL SHIFT EAST
THROUGH THE LOWER GREAT LAKES AND REDUCE THE DIRECT INTERACTION OF
IT WITH THE SECONDARY SHORTWAVE NOW SLIDING SOUTH THROUGH WESTERN
LAKE SUPERIOR AND THE MINNESOTA ARROWHEAD. WHILE THIS WILL LIKELY
WEAKEN THE SYNOPTICLY FORCED PRECIPITATION...THE COLDER AIR SURGING
OVER LAKE SUPERIOR ON TUESDAY (850MB TEMPS FALLING TO AROUND -14C
OVER THE WESTERN LAKE) SHOULD LEAD TO A TRANSITION TO LAKE
ENHANCED/EFFECT SNOW OVER THE WEST INITIALLY AND THEN SHIFTING EAST
ACROSS THE REST OF THE AREA BY EVENING. CONFIDENCE DOES BEGIN TO
WAVER SOME ON TUESDAY AND CONTINUE INTO WEDNESDAY AS THE TWO
SHORTWAVE INTERACT WITH EACH OTHER OVER THE GREAT LAKES REGION.
THIS LEADS TO DIFFERENCES IN THE EXACT MODEL SOLUTIONS...BUT THE
GENERAL IDEA IS FOR THE SURFACE LOW TO CONTINUE EAST...LEAVING A
TROUGH STRETCHED WEST-NORTHWEST ACROSS LAKE SUPERIOR ON TUESDAY
AFTERNOON/EVENING UNTIL THE TRAILING SHORTWAVE CAN SLIDE IT SOUTH
WEDNESDAY. THE 00Z GFS DOES DIFFER FROM THIS IDEA AND LINGERS THE
TROUGH OVER THE UPPER GREAT LAKES UNTIL THURSDAY MORNING...WHILE THE
00Z ECMWF CAME IN A LITTLE SLOWER BUT NOT AS DELAYED AS THE GFS.
WILL FOLLOW THE GENERAL CONSENSUS AT THIS POINT AND HAVE IT MOVING
SOUTH ON TUESDAY NIGHT INTO WEDNESDAY. THEREFORE...SHOULD SEE A
PERIOD OF NORTHERLY FLOW LAKE EFFECT SPREADING ACROSS THE AREA ON
TUESDAY INTO TUESDAY NIGHT FROM WEST TO EAST AND CONTINUING INTO
WEDNESDAY. UNTIL THE COLDER AIR CAN MOVE INTO THE AREA LATER
TUESDAY AFTERNOON AND NIGHT...EXPECT THE LAKE ENHANCED PRECIPITATION
INTENSITY TO BE LIMITED TO THE WEST HALF AND WHERE IT SNOWS THE
RATIOS WILL BE ON THE LOW END (AROUND 12-1). AS THAT COLDER AIR
MOVES IN...THE CLOUD LAYER WILL NOSE INTO THE DGZ AND INCREASE THE
RATIOS...BUT THE AREA WILL ALSO START TO SEE THE AFFECT OF THE HIGH
BUILDING SOUTH INTO SOUTHERN CANADA AND THE NORTHERN PLAINS. THAT
WILL STRENGTHEN THE INVERSION AROUND 5KFT AND HELP LIMIT THE
STRENGTH OF THE LAKE EFFECT PRECIPITATION. WHILE MUCH OF THE
FORECAST DEPENDS ON THE TIMING OF THAT SURFACE TROUGH DROPPING
ACROSS THE AREA...STILL WOULD EXPECT MANY LOCATIONS IN THE NORTHERLY
WIND SNOW BELTS TO SEE A COUPLE TO SEVERAL INCHES OF LAKE
ENHANCED/EFFECT SNOW TUESDAY AFTERNOON INTO WEDNESDAY. WILL
ALSO HIGHLIGHT THIS POTENTIAL IN THE HWO AS SOME AREAS MAY SEE
ADVISORY SNOWFALL.
BEHIND THE SURFACE TROUGH...EXPECT THE LAKE EFFECT TO DIMINISH
WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING AS THE AREA OF HIGH
PRESSURE BEGINS TO SLIDE SOUTHEAST INTO THE UPPER GREAT LAKES
REGION. WARMING TEMPERATURES ALOFT WILL ARRIVE WITH UPPER RIDGE AND
LEAD TO A QUIET END TO THE WORK WEEK AND LIKELY INTO NEXT WEEKEND.
MODELS ARE FAIRLY CONSISTENT ON THE HIGH REMAINING OVER THE UPPER
GREAT LAKES REGION THROUGH THIS PERIOD. AS FOR TEMPERATURES...EXPECT
HIGHS IN THE MID-UPPER 20S FOR THE END OF THE WORK WEEK THAT MAY TRY
TO NOSE INTO THE LOWER 30S FOR NEXT WEEKEND (WHICH WOULD BE AROUND 5
DEGREES ABOVE NORMAL FOR THAT TIME OF DECEMBER).
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 842 PM EST SAT DEC 13 2014
IN THE PRESENCE OF DIURNAL COOLING...SLOWLY DIMINISHING SW WINDS AND
THE ARRIVAL OF MOISTER LLVL AIR OVER MELTING SN PACK...EXPECT
CONDITIONS AT CMX AND SAW TO DETERIORATE TO LIFR AND THEN VLIFR
OVERNGT. DOWNSLOPE WIND COMPONENT AT IWD WL LIKELY WL LIKELY LIMIT
THE WORST CONDITIONS TO LIFR THERE. THERE WL BE ONLY A SLOW RECOVERY
TO IFR CONDITIONS ON SUN AFTN WITH CONTINUED INFLUX OF MORE LLVL
MSTR AND LO SUN ANGLE HINDERING A MORE SGNFT IMPROVEMENT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 511 AM EST SUN DEC 14 2014
A RIDGE ACROSS THE UPPER GREAT LAKES WILL SLOWLY SHIFT TO THE LOWER
GREAT LAKES SUNDAY INTO MONDAY. LOOK FOR AN ELONGATED AREA OF LOW
PRESSURE ACROSS THE PLAINS STATES SUNDAY MORNING TO PUSH ACROSS LAKE
SUPERIOR LATE SUNDAY NIGHT INTO MONDAY...AS THE S END OF THE TROUGH
DEEPENS ACROSS IOWA ON MONDAY. THE LOW WILL PUSH ACROSS LOWER
MICHIGAN ON TUESDAY...AND EXIT ACROSS THE LOWER GREAT LAKES TUESDAY
NIGHT. A TIGHTENING GRADIENT BEHIND THE LOW PRES SYSTEM LATE MONDAY
NIGHT INTO TUESDAY IS EXPECTED TO BRING NORTH WINDS GUSTING TO 30
KNOTS WITH A FEW GALE FORCE GUSTS TO 35 KNOTS.
WINDS WILL DIMINISH FROM WED INTO WED NIGHT AS THE LOW MOVES AWAY
AND HIGH PRESSURE HIGH PRESSURE BUILDS TOWARD THE WRN LAKES FROM THE
PLAINS. WINDS WILL THEN REMAIN AT OR BELOW 20 KNOTS THU AS THE HIGH
SETTLES OVER THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1013 AM EST SUN DEC 14 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD ACROSS THE AREA TO START THE WEEK RESULTING
IN SLOWLY RISING TEMPERATURES TODAY THROUGH TUESDAY. HIGH
TEMPERATURES WILL BE IN THE MID 30S TODAY AND THE MID 40S BY
TUESDAY. DESPITE THE HIGH PRESSURE...MOSTLY CLOUDY SKIES WILL REMAIN
IN PLACE THANKS TO SOME TRAPPED LOW-LEVEL MOISTURE. A LOW PRESSURE
SYSTEM WILL BRING RAIN ACROSS THE AREA ON TUESDAY...WITH A
TRANSITION TO SNOW BY WEDNESDAY INTO THURSDAY AS COLDER AIR ARRIVES
FOR THE SECOND HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE 12Z BUF SOUNDING SHOWS A VERY STRONG INVERSION IN PLACE...AND
IT WOULD BE A PRETTY NICE DAY WITH TEMPERATURES IN THE UPPER 40S
IF YOU CAN MANAGE TO GET UP TO 7000FT (ABOUT 775MB). HOWEVER...BENEATH
THIS IS LOTS OF MOISTURE...ESPECIALLY BENEATH 900 MB. THIS WILL
RESULT IN ANOTHER CLOUDY DAY ACROSS THE REGION...WITH NEAR STEADY
TEMPERATURES IN THE MID TO UPPER 30S. A 20 KT WNW FLOW AT 925MB IS
FORECAST TO DIMINISH THIS AFTERNOON AND FURTHER THIS EVENING WHICH
SHOULD CAUSE DRIZZLE TO EVENTUALLY TAPER OFF.
MESONET SHOWS A FEW SPOTS ACROSS HIGHER TERRAIN IN JEFFERSON/LEWIS
COUNTIES THAT IS BELOW FREEZING...WITH SOME PATCHY FREEZING
DRIZZLE POSSIBLE IN THESE AREAS FOR THE REMAINDER OF THE MORNING
HOURS. THERE IS ALSO SOME PRETTY DENSE FOG IN PLACE WITH A SURFACE
WIND SHIFT TO THE NORTHWEST LEADING TO MOISTURE CONVERGENCE IN THE
BOUNDARY LAYER.
GIVEN THAT THE INVERSION IS FORECAST TO REMAIN IN PLACE...SEE
LITTLE OPPORTUNITY FOR ANY CLEARING TODAY...WITH ANOTHER CLOUDY
DAY EXPECTED REGION-WIDE.
BY TONIGHT...EXPECT STRATUS DECK TO LARGELY REMAIN IN PLACE. MODELS
HINT AT THE POSSIBILITY FOR SOME BREAKS IN THE CLOUDS ACROSS THE
NORTH COUNTRY...WHICH IF THEY OCCUR WOULD RESULT IN MUCH COOLER
OVERNIGHT LOW TEMPERATURES INLAND FROM LAKE ONTARIO.
HOWEVER...CONFIDENCE IN THESE CLOUDS BREAKING UP REMAINS VERY LOW.
THUS HAVE KEPT OVERNIGHT LOWS UP AROUND FREEZING FOR MOST
LOCATIONS...WITH SOME 20S POSSIBLE IN THE NORTH COUNTRY. NOT
EXPECTING TO SEE MUCH DRIZZLE AGAIN TONIGHT FOR TWO REASONS...1/
LIGHTER WINDS TURNING SOUTHERLY BY MORNING WILL ELIMINATE THE
UPSLOPE ASPECT AND COULD PROMOTE A LITTLE DOWNSLOPE DRYING AND 2/
FORECAST SOUNDINGS INDICATE A SLIGHTLY WARMER LOW-LEVEL LAYER
GETTING TEMPERATURES ABOVE THE IDEAL RANGE FOR DRIZZLE FORMATION. WE
COULD SEE SOME PATCHY FOG DEVELOP ACROSS THE HIGHER TERRAIN OF THE
WESTERN SOUTHERN TIER...BUT CONFIDENCE IN A DENSE FOG REPEAT
PERFORMANCE IS LOW DUE TO THE LACK OF AN UPSLOPE COMPONENT TO THE
WIND.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
ON MONDAY A STRONG MID LEVEL RIDGE WILL CREST OVER THE LOWER LAKES
REGION. NORMALLY THIS WOULD BRING UNSEASONABLE WARMTH TO OUR REGION
GIVEN 850MB TEMPS OF NEAR +8C IN THE MORNING...HOWEVER WE WILL STILL
HAVE A VERY PERSISTENT AND STRONG LOW LEVEL INVERSION IN PLACE. THIS
WILL PREVENT WARMER TEMPERATURES FROM BEING REALIZED...AND WILL ALSO
HELP TO KEEP EXTENSIVE LOW LEVEL MOISTURE TRAPPED. THIS WILL LIKELY
KEEP THE SEMI-PERMANENT STRATUS DECK IN PLACE FOR MUCH OF THE
REGION. EXPECT HIGHS IN THE UPPER 30S ACROSS WESTERN NY WITH SOME
LOWER 40S POSSIBLE ALONG THE LAKE ERIE SHORE. THE NORTH COUNTRY WILL
REMAIN IN THE LOW TO MID 30S.
MONDAY NIGHT SOUTHERLY RETURN FLOW WILL INCREASE AS HIGH PRESSURE
DRIFTS TO THE EASTERN SEABOARD IN RESPONSE TO A STRONG TROUGH
SWINGING THROUGH THE MIDWEST. THIS WILL FINALLY BEGIN TO DISLODGE
THE STRATUS DECK...BUT JUST IN TIME FOR INCREASING MID LEVEL CLOUDS
AHEAD OF THE NEXT SYSTEM. A LEAD MID LEVEL SHORTWAVE AND 700MB JET
WILL BRING INCREASING ASCENT LATE ACROSS WESTERN NY...WITH SHOWERS
ARRIVING BEFORE DAYBREAK. TEMPERATURES WILL BEGIN TO RISE LATER
MONDAY NIGHT IN RESPONSE TO BETTER MIXING...SO EXPECT EVERYTHING TO
BE LIQUID WHEN IT ARRIVES.
TUESDAY AND TUESDAY NIGHT A STRONG MID LEVEL TROUGH WILL SWING
THROUGH THE GREAT LAKES AND BRING A PERIOD OF ORGANIZED LARGE SCALE
ASCENT AND DEEPER MOISTURE. A SURFACE LOW WILL TRACK ACROSS LOWER
MICHIGAN TUESDAY BEFORE REACHING SOUTHERN ONTARIO BY WEDNESDAY
MORNING. THE MID LEVEL TROUGH AND ASSOCIATED UPPER LEVEL DIVERGENCE
WILL BRING A FEW PERIODS OF RAIN SHOWERS MOVING FROM SOUTHWEST TO
NORTHEAST ACROSS THE AREA TUESDAY AND TUESDAY NIGHT. THE SURFACE
COLD FRONT WILL NOT ARRIVE UNTIL WEDNESDAY MORNING...AND FORECAST
PROFILES SUPPORT ALL RAIN AS PTYPE THROUGH THAT TIME. OVERALL QPF
APPEARS TO BE ON THE LIGHT SIDE...WITH A QUARTER TO THIRD OF INCH IN
MOST PLACES. THE WARMER TEMPERATURES...HIGHER DEWPOINTS...WIND AND
RAIN WILL MELT MOST IF NOT ALL OF THE SNOW THAT REMAINS ON THE
GROUND...BUT THERE IS NOT ENOUGH WATER IN THE SNOW PACK FOR ANY
FLOOD CONCERNS.
ON WEDNESDAY STEADY COLD ADVECTION BEHIND THE COLD FRONT WILL BRING
A SLOW DROP IN TEMPERATURES THOUGH THE DAY. MOST OF THE STEADIER
SHOWERS WILL FOCUS ON THE NORTH COUNTRY WHERE DEEPER MOISTURE AND
ASCENT REMAIN. RAIN SHOWERS WILL GRADUALLY MIX WITH WET SNOW...AND
MAY CHANGE TO MAINLY SNOW ACROSS HIGHER TERRAIN IN THE AFTERNOON.
FARTHER WEST EXPECT JUST A FEW SCATTERED RAIN AND SNOW SHOWERS FROM
THE FINGER LAKES WESTWARD. IT WILL BECOME BREEZY TO ALMOST WINDY IN
THE COLD ADVECTION REGIME BEHIND THE COLD FRONT...WITH GUSTS OF
30-35 KNOTS POSSIBLE ESPECIALLY EAST AND NORTHEAST OF THE LAKES.
WEDNESDAY NIGHT 850MB TEMPS CONTINUE TO DROP TO AROUND -8C TO -10C.
THIS WILL CHANGE ANY REMAINING PRECIP OVER TO ALL SNOW. IT WILL
BECOME COLD ENOUGH FOR SOME LIMITED LAKE RESPONSE EAST OF THE
LAKES...BUT THE SHALLOW NATURE OF THE COLD AIRMASS WILL KEEP LAKE
INSTABILITY RELATIVELY WEAK.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
ON THURSDAY THE LOW LEVEL FLOW WILL BECOME MORE NORTHWEST...WITH
TEMPS ALOFT JUST COLD ENOUGH TO CONTINUE TO SUPPORT SOME WEAK LAKE
EFFECT AND UPSLOPE SNOW SHOWERS. GIVEN THE WEAK INSTABILITY AND
SHORT FETCH ANY ACCUMULATIONS SHOULD BE VERY MINOR. THIS WILL SLOWLY
COME TO AN END THURSDAY NIGHT AS THE AIRMASS MODERATES AND BECOMES
TOO MILD TO SUPPORT A LAKE RESPONSE.
FRIDAY SHOULD BE MAINLY DRY AS A WEAK RIDGE OF HIGH PRESSURE EXTENDS
FROM NORTHWEST ONTARIO INTO THE LOWER LAKES. TEMPERATURES WILL
REMAIN IN THE COOL SIDE THURSDAY AND FRIDAY...JUST A LITTLE BELOW
AVERAGE FOR MID DECEMBER.
MODEL GUIDANCE BEGINS TO DIVERGE BY SATURDAY WITH THE GFS FASTER AND
FARTHER NORTHWEST WITH A SOUTHERN STREAM TROUGH MOVING THROUGH THE
OHIO VALLEY. THE ECMWF REMAINS SLOWER AND FARTHER SOUTH WITH THIS
FEATURE...AND THIS IS MORE IN LINE WITH THE PREVIOUS 12Z/13 GEFS
ENSEMBLE MEAN. FOR NOW WILL STICK WITH A DRY FORECAST ON SATURDAY IN
FAVOR OF A SLOWER SOLUTION. THIS SYSTEM WILL BEAR WATCHING HOWEVER
FOR NEXT WEEKEND AS THE PATTERN REMAINS SOMEWHAT FAVORABLE FOR THIS
SOUTHERN STREAM SYSTEM TO SUPPORT ANOTHER NORTHEAST COASTAL STORM.
THE CURRENT RUN OF THE ECMWF KEEPS ANY IMPACTS JUST SOUTH AND EAST
OF OUR REGION...BUT THIS IS STILL A WEEK AWAY AND EXPECT PLENTY OF
MODEL VARIATION OVER THE NEXT FEW DAYS.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
AT 15Z...CONDITIONS VARIED ACROSS THE REGION...BUT MOST TAF SITES
WERE IFR OR LOWER. ROC WAS A NOTABLE EXCEPTION...BUT GIVEN
SATELLITE TRENDS EXPECT THAT THIS BRIEF POCKET OF VFR CONDITIONS IS
VERY SMALL AND IT SOON WILL COME IN LINE WITH OTHER LOCATIONS.
FOR THIS MORNING...EXPECT BUF/IAG/ROC/JHW TO GENERALLY REMAIN
STEADY STATE...PERHAPS BOUNCING SLIGHTLY...BUT GENERALLY AVERAGING
NEAR THEIR 15Z OBS POINT. EXPECT A LOWERING TREND AT ART...WHERE
WINDS SHIFTING TO THE NW WILL ENHANCE BOUNDARY LAYER MOISTURE
CONVERGENCE AND LOWER CIGS/VSBY.
LATE THIS AFTERNOON/EVENING...EXPECT CIGS TO LOWER WITH THE WIND
SHIFT TO THE NORTHWEST. TRENDS OF THE HRRR AVIATION GUIDANCE
APPEAR TO CAPTURE THIS TREND WELL.
THE FORECAST IS MORE DIFFICULT TONIGHT...WITH WINDS DIMINISHING
AND EVENTUALLY GOING NEARLY CALM UP TO 850MB. THE LACK OF FLOW
WILL PROBABLY RESULT IN NO DRIZZLE...BUT ITS UNCERTAIN IF THIS
WILL ALLOW GROUND FOG TO DEVELOP...OR IF CONDITIONS WILL
ESSENTIALLY REMAIN STEADY STATE WITH PERSISTENT IFR CIGS. EITHER
WAY...EXPECT IFR OR LOWER CONDITIONS FOR MOST OF THE AREA...WITH
LOWER VSBY POSSIBLE. NAM/GFS/LAMP MOS GUIDANCE CONTINUES TO BE TOO
OPTIMISTIC WITH CONDITIONS...WITH THE LOWEST CIGS LIKELY TO BE AT
JHW DUE TO THE HIGHER TERRAIN. LOWEST FORECAST CONFIDENCE IS AT
BUF/ROC/IAG...WHERE THE HRRR HINTS AT THE POSSIBLE DEVELOPMENT OF
LIFR CIGS AND GROUND FOG.
OUTLOOK...
MONDAY...MVFR/IFR IMPROVING TO VFR.
TUESDAY...AREAS OF MVFR IN RAIN SHOWERS.
WEDNESDAY AND THURSDAY...VFR/MVFR WITH A CHANCE OF SNOW SHOWERS.
&&
.MARINE...
WINDS AND WAVES WILL DROP JUST BELOW SMALL CRAFT CONDITIONS LATER
THIS MORNING AS THE PRESSURE GRADIENT RELAXES ACROSS THE LOWER
LAKES. HIGH PRESSURE WILL MOVE ACROSS THE LOWER LAKES TO START THE
WEEK...WITH QUIET CONDITIONS EXPECTED. THE NEXT CHANCE FOR HIGHER
WINDS AND WAVES ACROSS THE LAKES WILL BE WEDNESDAY AS A LOW PRESSURE
SYSTEM MOVES ACROSS THE GREAT LAKES.
&&
.CLIMATE...
A RELATIVELY MILD PATTERN WILL CONTINUE THROUGH THE NEXT 10 DAYS OR
SO WITH ONLY RELATIVELY BRIEF INTRUSIONS OF COLDER AIR MOST NOTABLY
LATER THIS WEEK. ONE MORE SOUTHERN STREAM SYSTEM WILL BEAR WATCHING
FOR A POSSIBLE NORTHEAST STORM NEXT WEEKEND.
THERE ARE GROWING SIGNS THAT THIS RELATIVELY MILD PATTERN WILL COME
TO AN END TOWARDS THE END OF THE MONTH. GEFS AND NAEFS ENSEMBLES
OVER THE PAST SEVERAL DAYS CONTINUE TO SUPPORT A TREND OF LOWERING
NAO INDEX AND THE DEVELOPMENT OF A STRONGER POSITIVE PNA TYPE
PATTERN WITH A BUILDING WEST COAST RIDGE FORCING DOWNSTREAM TROUGH
AMPLIFICATION ACROSS THE CENTRAL AND EASTERN CONUS. IT APPEARS THIS
PATTERN WILL HAVE SOME STAYING POWER...SO EXPECT A TREND TOWARDS
MORE PERSISTENT MID WINTER COLD BY THE END OF THE MONTH. IT APPEARS
THIS PATTERN CHANGE WILL BEGIN IN EARNEST SOMETIME AROUND CHRISTMAS
DAY...PLUS OR MINUS A FEW DAYS. THERE ARE SOME SIGNS IN GEFS
ENSEMBLE MEMBERS THAT THE START OF THE PATTERN CHANGE MAY BE USHERED
IN WITH A SIGNIFICANT SYSTEM SOMEWHERE IN THE EASTERN CONUS. STAY
TUNED.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...CHURCH
NEAR TERM...APFFEL/CHURCH
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...APFFEL/CHURCH
MARINE...CHURCH
CLIMATE...HITCHCOCK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
923 AM EST SUN DEC 14 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD SLOWLY EAST TODAY AND BE EAST OF THE AREA
BY THIS AFTERNOON. LOW PRESSURE WILL APPROACH FROM THE WEST AND BE
OVER LAKE ERIE BY TUESDAY EVENING. THE LOW WILL FORCE A COLD FRONT
EAST ACROSS THE AREA TUESDAY AFTERNOON AND EVENING. HIGH PRESSURE
WILL REMAIN NEARLY STATIONARY OVER MINNESOTA AND EXPAND EAST OVER
THE REGION BY FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL BE IN CONTROL OF THE LOCAL AREA THROUGH THE DAY
TODAY. HOWEVER...STRONG INVERSION WILL REMAIN PRESENT AS WARM AIR
ADVECTION TAKES PLACE MORE SO ALOFT THAN AT THE SURFACE. THIS WILL
KEEP THE LOW LEVEL MOISTURE TRAPPED UNDER THE INVERSION. LATEST
SOUNDINGS AND MODEL SOUNDINGS INDICATE DEEP LOW LEVEL MOISTURE
PRODUCING STRATUS DECK WILL REMAIN PERSISTENT THROUGH THE DAY TODAY.
DRIZZLE HAS REDEVELOPED AROUND THE CLE METRO AREA SO WILL ADD
MENTION BACK INTO THE FORECAST. HRRR SEEMS TO CONTINUE WITH PATCHY
DRIZZLE THRUT THE DAY FROM THE WEAK WARM ADVECTIVE LIFT SO WILL
FOLLOW SUIT IN THE FORECAST.
BUMPED UP TEMPERATURES ACROSS THE AREA...ESPECIALLY IN THE WEST
WHERE A BRIEF PEEK AT THE SUN COULD OCCUR THIS AFTERNOON AND HELP
BOOST TEMPERATURES. OTHERWISE...GENERALLY 40S FOR HIGHS TODAY AND
NEAR 50 IN THE WEST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL RIDGE AND SURFACE HIGH PRESSURE WILL KEEP THE THREAT FOR
STRATUS DECK IN PLACE OVERNIGHT. WILL ALSO MENTION THE POTENTIAL FOR
PATCHY DRIZZLE AND PATCHY FOG DURING THE EVENING IN THE WEST AND
OVERNIGHT ELSEWHERE. SOME DRIER AIR WILL BEGIN TO PUSH INTO THE
WESTERN PORTIONS OVERNIGHT AND THIS SHOULD HELP TO LIFT SOME OF THE
STRATUS IN THAT AREA. NO GO FOR THE EASTERN TWO THIRDS OF THE AREA
THOUGH. TEMPERATURES STILL REMAIN ABOVE FREEZING AND THERE IS NO
RISK OF FREEZING PRECIPITATION.
MATTER OF FACT...IT LOOKS LIKE EVEN THOUGH WE START TO SEE SOME
DRIER AIR ON MONDAY...ELEVATED LOW LEVEL MOISTURE HOLDS STRONG TO
PREVENT ANY SUN SO WILL KEEP THE CLOUDY SKIES. NEXT SYSTEM BEGINS TO
APPROACH THE FORECAST AREA BY MONDAY EVENING AS LOW PRESSURE MOVES
NORTHEAST TO LAKE ERIE. THIS WILL FORCE A COLD FRONT ACROSS THE AREA
TUESDAY INTO TUESDAY EVENING. SHOWERS WITH THE COLD FRONT ARE
EXPECTED AS MOISTURE IN ASSOCIATION WITH THE STORM SYSTEM TRACKS
NORTHEAST INTO THE AREA.
ONCE COLD FRONT SLIDES EAST...IT WILL TAKE SOME TIME FOR THE COLDER
AIR TO ARRIVE. THIS SHOULD HOLD OFF UNTIL WEDNESDAY MORNING. LAKE
TEMPERATURE AND 850 MB TEMPERATURE DIFFERENCE IS MINIMAL BUT STILL
EXPECTING SOME LAKE EFFECT SNOW SHOWERS TO DEVELOP WITH SOME LIGHT
SNOW ACCUMULATIONS IN THE NORTHEAST WEDNESDAY INTO WEDNESDAY NIGHT.
MILD TEMPERATURES IN THE 40S FOR HIGHS EACH DAY WILL SETTLE BACK
INTO THE 30S ON WEDNESDAY. OVERNIGHT LOWS RETURN BACK TO THE 20S BY
WEDNESDAY NIGHT IN THE COLD AIR ADVECTION FLOW IN THE WAKE OF THE
LOW AND ADVANCE OF THE SURFACE HIGH PRESSURE.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
LOW PRESSURE WILL BE NEAR THE NEW ENGLAND COAST ON THURSDAY WITH
TEMPERATURES COLD ENOUGH TO PRODUCE SOME LAKE EFFECT SNOW SHOWERS
INTO THURSDAY NIGHT. HIGH PRESSURE SHOULD RIDGE INTO THE AREA FROM
CENTRAL ONTARIO KEEPING THE AREA DRY ON FRIDAY. MODELS THEN BEGIN
TO DIFFER ON THE HANDLING OF THE SOUTHERN JET STREAM LOW THAT
DEVELOPS OVER TEXAS ON FRIDAY. THE ECMWF TYPICALLY HANDLES STORM
SYSTEMS FROM THIS AREA OF THE COUNTRY BETTER THAN THE GFS. SO HAVE
LEANED TOWARD THE SLOWER ARRIVAL OF THE PRECIPITATION ON SATURDAY.
STILL WOULD NOT BE SURPRISED TO SEE THIS STORM SYSTEM EJECT
NORTHEASTWARD SLOWER THAN CURRENT THINKING.
TEMPERATURES FOR LONG TERM WE GENERALLY BE IN THE 20S FOR LOWS AND
30S FOR HIGHS.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
LOW END MVFR CEILINGS HAVE DEVELOPED OVER THE THE WESTERN 2/3RDS
OF NORTHERN OHIO EARLY THIS MORNING. EXPECT THESE MVFR CONDITIONS
TO GRADUALLY SPREAD ACROSS THE REMAINDER OF NE OHIO INTO NW PA
THROUGH LATE MORNING. ALL LOCATIONS SHOULD THEN REMAIN MVFR
THROUGH THE AFTERNOON WITH SEVERAL LOCATIONS IMPROVING ABOVE 2000
FEET. HOWEVER THE BEST CHANCES OF THIS OCCURRING WILL BE NEAR AND
WEST OF A LINE FROM KCLE TO KCAK.
WESTERLY WINDS WILL GRADUALLY BECOME SOUTHWEST AND DECREASE
THROUGH THE AFTERNOON. OVERNIGHT WINDS WILL BE LIGHT AND VARIABLE
BECOMING LIGHT SOUTHERLY. THE LIGHT WINDS SHOULD ALLOW FOR AREAS
OF FOG AND LOWERING CEILINGS. BELIEVE ALL LOCATIONS SHOULD DIP
BACK TO IFR AFTER THE 03Z TO 05Z TIME FRAME.
.OUTLOOK...NON VFR LIKELY MONDAY. AREAS OF NON VFR TUESDAY IN
RAIN SHOWERS AND ACROSS FAR NE OH/NW PA ON WEDNESDAY IN LAKE
EFFECT SNOW SHOWERS.
&&
.MARINE...
SMALL CRAFT ADVISORY WILL CONTINUE THROUGH MID MORNING. WINDS AND
WAVES SHOULD AS HIGH PRESSURE WEAKENS AND BEGINS TO SLIDE EAST. LOW
PRESSURE WILL THEN BEGIN TO MOVE INTO THE CENTRAL GREAT LAKES ON
MONDAY WITH SOUTHERLY WINDS ANTICIPATED. THE SOUTHERLY WINDS WILL
INCREASE MONDAY NIGHT BUT WILL SHIFT TO THE WEST AND NORTHWEST IN
THE WAKE OF A COLD FRONT THAT SHOULD CROSS THE LAKE TUESDAY EVENING.
WINDS WILL INCREASE WITH THE COLD ADVECTION IN THE WAKE OF THE
FRONT. AT THIS POINT IT APPEARS WINDS WILL REMAIN IN THE 15 TO 25
KNOT RANGE SO A SMALL CRAFT ADVISORY WILL BE NEED TUESDAY NIGHT INTO
AT LEAST WEDNESDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 9 AM EST THIS MORNING FOR
LEZ146>149.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY/ADAMS
SHORT TERM...LOMBARDY
LONG TERM...MULLEN
AVIATION...MULLEN
MARINE...MULLEN
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
558 AM CST SUN DEC 14 2014
.AVIATION...
FOR THE 12Z TAFS...TIMING THE ONSET OF SHOWERS AND THUNDERSTORMS
NEAR AREA TAF SITES IS THE PRIMARY FORECAST CONCERN TODAY.
CLOSELY FOLLOWED THE LATEST HRRR MODEL GUIDANCE FOR TIMING THE
ONSET OF PRECIPITATION AT AREA TAF SITES TODAY. EXPECT SCATTERED
RAIN SHOWERS TO BEGIN TO DEVELOP ALONG THE INTERSTATE 35 CORRIDOR
BY LATE THIS MORNING. THINK THAT THE BEST CHANCE FOR THUNDERSTORMS
WILL EXIST AS UPPER LEVEL FORCING INCREASES ACROSS THE AREA THIS
AFTERNOON. WENT AHEAD WITH A MENTION OF VCTS IN THE TAFS FROM
20-23Z AS THIS IS WHEN THE HRRR...AND OTHER HIGH RESOLUTION
MODELS...INDICATE THE MOST INTENSE CONVECTION MOVES ACROSS THE DFW
AREA TODAY.
RAIN SHOWERS WILL REMAIN POSSIBLE UNTIL A DRYLINE TYPE BOUNDARY
MOVES EAST ACROSS THE AREA THIS EVENING. THE 06Z NAM HINTED THAT A
SECOND LINE OF THUNDERSTORMS MAY ACCOMPANY THIS BOUNDARY AS IT
MOVES ACROSS AREA TAF SITES AROUND 03Z...BUT JUST KEPT THINGS AS
RAIN SHOWERS AT THIS TIME. ANY THUNDERSTORMS TODAY WILL HAVE THE
POTENTIAL TO BRING SOME STRONG WINDS DOWN TO THE SURFACE.
MODELS INDICATE THAT A LOW-LEVEL JET OF 45-50 KTS WILL REMAIN IN
PLACE OVER NORTH AND CENTRAL TEXAS ALL DAY TODAY. ANY ORGANIZED
DOWNDRAFT COULD TRANSPORT THIS HIGH MOMENTUM AIR DOWN TO THE
SURFACE...RESULTING IN STRONG TO DAMAGING WINDS REACHING THE
GROUND. DID NOT PLACE STRONG WINDS IN THE TAFS RIGHT NOW AS THIS
WILL NEED TO BE HANDLED ON A SHORT TERM FORECAST BASIS.
BEHIND THE DRYLINE TYPE BOUNDARY/FRONT...SKIES WILL CLEAR OUT AS
DRIER AIR BUILDS ACROSS THE REGION. MODELS INDICATE THAT WINDS
WILL VEER FROM THE SOUTHWEST TO THE WEST AFTER SUNRISE MONDAY
MORNING AS A TRUE COLD FRONT MOVES SOUTH ACROSS THE SOUTHERN
PLAINS. WINDS APPEAR TO BE WEAK ENOUGH TO PREVENT ANY SIGNIFICANT
CROSSWIND ISSUES...HOWEVER WE WILL HAVE TO WATCH THIS PERIOD OF
WESTERLY WINDS VERY CLOSELY TOMORROW MORNING IN CASE WINDS ARE
STRONGER THAN ADVERTISED.
CAVANAUGH
&&
.PREV DISCUSSION... /ISSUED 327 AM CST SUN DEC 14 2014/
RAIN CHANCES INCREASE ACROSS MUCH OF THE REGION TODAY AND TONIGHT
AS THE UPPER LEVEL TROUGH CONTINUES TO MOVE TOWARD THE SOUTH
PLAINS. 00Z UPPER AIR ANALYSIS HAD THE BASE OF THE TROUGH LOCATED
ROUGHLY BETWEEN SALT LAKE CITY AND PHOENIX...AND THE 08Z SATELLITE
DATA SUGGESTS THE BASE QUICKLY MOVING INTO NEW MEXICO. SYNOPTIC
SCALE AND MESOSCALE MODELS HAVE BEEN SUGGESTING THE TRANSITION TO
A CLOSED LOW OVER NEW MEXICO BY 12Z...AND THE SATELLITE DATA
CONFIRMS THAT THIS IS INDEED TAKING PLACE AS CIRCULATION CAN BE
SEEN IN THE SATELLITE DATA TO THE WEST OF KABQ. THIS FEATURE IS
EXPECTED TO MOVE NORTHEAST SOUTHERN KANSAS BY THIS EVENING.
AS THE UPPER LOW MOVES NORTHEAST...THERE WILL BE SUFFICIENT SYNOPTIC
SCALE LIFT ACROSS MUCH OF NORTH AND CENTRAL TEXAS. WITH ABUNDANT
MOISTURE IN PLACE...AND INCREASING WITH A STRONG SOUTHERLY LOW
LEVEL JET...THERE WILL BE A DECENT SHOT AT SHOWERS AND
THUNDERSTORMS TODAY. HAVE LEANED STRONGLY ON HIGH RESOLUTION
MESOSCALE MODELS...ESPECIALLY THE HRRR...FOR THE FORECAST
TODAY...INCREASING POPS FROM WEST TO EAST THROUGHOUT THE DAY. IF
ALL GOES ACCORDING TO PLAN...SHOWERS AND THUNDERSTORMS SHOULD
INCREASE IN COVERAGE BETWEEN 9 AM AND NOON TO THE WEST OF
I35/I35W. BETWEEN NOON AND 3 PM...EXPECT THE SHOWERS AND
THUNDERSTORMS TO IMPACT THE I35 CORRIDOR...INCLUDING BOTH I35W AND
I35E. THE STORMS WILL MOVE EAST FROM THERE AND PUSH EAST OF THE
AREA AFTER MIDNIGHT.
SEVERE WEATHER CHANCES TODAY ARE LOW...BUT NOT COMPLETELY OUT OF
THE QUESTION. FORECAST CAPE VALUES...AGAIN LEANING HEAVILY ON THE
HRRR...SUGGEST SOMEWHERE BETWEEN 500 AND 1000 J/KG WHICH IS NOT
TOO SHABBY FOR MID DECEMBER. LAPSE RATES SHOULD INCREASE AS THE
UPPER STORM MOVES CLOSER TO US...AND WOULD ALSO ANTICIPATE ANY CIN
TO DECREASE AS THE ENTIRE COLUMN COOLS IN RESPONSE TO SYNOPTIC
SCALE LIFT. WOULD EXPECT THAT ANY SEVERE STORM IS ISOLATED IN
COVERAGE AND WOULD BE THE EXCEPTION RATHER THAN THE RULE.
EXPECTING A PROGRESSIVE PATTERN TO CONTINUE FOR MUCH OF THE WEEK
AS TODAYS SYSTEM WILL GIVE WAY TO QUIETER WEATHER FOR MONDAY AND
TUESDAY. RAIN CHANCES INCREASE AGAIN WEDNESDAY AS THE NEXT WAVE
APPROACHES. POTENTIAL FOR RAIN CONTINUES THROUGH FRIDAY BEFORE A
RETURN TO RELATIVE QUIET FOR NEXT WEEKEND.
FOX
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 71 51 67 40 53 / 70 40 5 5 5
WACO, TX 70 51 67 40 57 / 60 50 5 5 10
PARIS, TX 66 53 63 37 51 / 70 80 10 5 5
DENTON, TX 70 47 64 36 53 / 70 30 5 5 5
MCKINNEY, TX 69 50 63 37 53 / 80 50 5 5 5
DALLAS, TX 71 51 67 41 54 / 70 40 5 5 5
TERRELL, TX 69 54 65 39 54 / 70 60 5 5 10
CORSICANA, TX 71 56 66 40 56 / 70 60 10 5 10
TEMPLE, TX 72 53 68 40 57 / 50 50 5 5 10
MINERAL WELLS, TX 71 43 64 35 55 / 40 10 5 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
910 AM CST SUN DEC 14 2014
.UPDATE...
ISSUED AT 910 AM CST SUN DEC 14 2014
NOT MUCH IMPROVEMENT IN VISIBILITIES EXPECTED THROUGH MONDAY
MORNING AS MILD/MOIST AIRMASS IS LIFTED ACROSS THE REGION.
THEREFORE THE DENSE FOG ADVISORY HAS BEEN EXTENDED THROUGH NOON
MONDAY.
UPDATE ISSUED AT 528 AM CST SUN DEC 14 2014
BECOMING VERY CONCERNED THAT THE DENSE FOG ADVISORY MAY NEED TO BE
EXTENDED FOR THE ENTIRE FORECAST AREA...POSSIBLY INTO MONDAY.
WITH UPPER 40S AND LOW TO MID 50S DEWPOINTS LURKING SOUTH OF THE
AREA NEAR I-80 BEING SHOVED NORTHWARD INTO OUR RELATIVELY SPEAKING
COLDER AIRMASS...ITS POSSIBLE THIS DENSE FOG GOES NOWHERE. ON TOP
OF THAT...LIGHTER WINDS ARE PROGGED TONIGHT...FAVORING LOW
VISIBILITIES. 14.10Z LAV GUIDANCE AT MOST SITES THAT ARE CURRENTLY
EXPERIENCING 1/4 MILE OR LESS VISIBILITIES...SUCH AS RST...CCY AND
MDZ...SHOWS THOSE VISIBILITIES PERSISTING THROUGH 11Z MONDAY...THE
END OF ITS RUN. WE MAY END UP HAVING TO WAIT FOR THE RAIN ON
MONDAY TO HELP IMPROVE VISIBILITIES SOMEWHAT...THOUGH DENSE FOG
COULD EASILY REFORM AFTER THE RAIN TAILS OFF. SOMETIME AFTER
MIDNIGHT MONDAY NIGHT APPEARS WHEN WE CAN FINALLY GET RID OF THE
FOG CONCERN...ACCOMPANYING THE COLD ADVECTION REGIME DEVELOPING
THEN.
HAVE NOT DONE ANY EXTENSIONS TO THE CURRENT ADVISORY...BUT THEY
COULD HAPPEN AT ANYTIME THROUGHOUT THE MORNING. THE HIGHEST
CONFIDENCE FOR THE DENSE FOG TO PERSIST IS ACROSS TAYLOR AND
CLARK COUNTIES...WHICH COINCIDES WITH THE COLDEST FORECAST
READINGS.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 255 AM CST SUN DEC 14 2014
THE MAIN FORECAST CONCERN CONTINUES TO BE THE PRECIPITATION
CHANCES THROUGH THE PERIOD.
LOCAL OBSERVATIONS CONTINUE TO SHOW DENSE FOG WITH VISIBILITIES OF
A QUARTER MILE OR LESS COVERING A GOOD SHARE OF THE AREA. THE
14.05Z RAP BUFKIT SOUNDINGS SUGGEST THE WINDS JUST ABOVE THE
SURFACE MAY DIMINISH A LITTLE BIT THROUGH THE REST OF THE NIGHT
INTO SUNDAY MORNING WITH A SLOWLY DEEPENING SATURATED LAYER. THIS
MAY ALLOW THE DENSE FOG TO BECOME A LITTLE MORE WIDESPREAD AND FOR
THE AREAS THAT HAVE DECENT VISIBILITY TO GO DOWN SOME. PLAN TO
LEAVE THE DENSE FOG ADVISORY IN PLACE WITH NO CHANGES.
STILL DEALING WITH THE ISSUE OF HOW MUCH IF ANY DRIZZLE IS
OCCURRING WITH THE FOG. BASED ON PERSONAL OBSERVATIONS...MUCH LESS
DRIZZLE WAS OCCURRING IN THE LOCAL AREA SATURDAY EVENING THAN
PREVIOUS NIGHTS. THE RAP CONTINUES TO SUGGEST THAT WHAT OMEGA
THERE WILL BE IN THE SATURATED LAYER WILL BE VERY NEAR THE TOP OF
THIS LAYER. THE 14.00Z GFS ALSO CONTINUES TO SHOW JUST SOME VERY
WEAK ISENTROPIC UP GLIDE OF 1 UBAR/S OR LESS ON THE 290K SURFACE.
WILL MAINTAIN THE MENTION OF DRIZZLE FOR THE ENTIRE DAY...BUT WILL
LOWER THE PRECIPITATION CHANCES OF MEASURABLE DOWN TO THE 2O TO 30
PERCENT RANGE. THIS WILL ALSO GIVE AREAS INSTEAD OF WIDESPREAD
DRIZZLE WHICH MOST LIKELY WILL BETTER FIT THE SCENARIO AS WELL.
THE MAIN PRECIPITATION EVENT STILL LOOKS TO MONDAY AND MONDAY
NIGHT. THE UPPER LEVEL LOW LIFTING OUT OF THE DESERT SOUTHWEST IS
EXPECTED TO MOVE INTO THE LOWER MISSOURI RIVER VALLEY TONIGHT AS
ANOTHER UPPER LEVEL LOW DROPS SOUTH FROM CENTRAL CANADA. EVEN
THOUGH THE MAIN UPPER LEVEL RIDGE WILL BE OVER THE EASTERN
CONUS...THE GFS SUGGESTS A SECONDARY RIDGE AXIS WILL EXTEND OFF
THE MAIN RIDGE AXIS ACROSS THE UPPER MIDWEST BETWEEN THE TWO UPPER
LEVEL LOWS. THIS WOULD KEEP THE MAJORITY OF THE FORCING AWAY FROM
THE AREA WITH THE GFS SUGGESTING JUST SOME WEAK QG CONVERGENCE
OCCURRING ACROSS THE WESTERN SECTIONS OF THE AREA WITH JUST THE
VERY WEAK ISENTROPIC UP GLIDE CONTINUING ON THE 290K SURFACE. WILL
TRIM THE RAIN CHANCES BACK TO THE 20 TO 40 PERCENT RANGE FOR THE
EVENING AND THEN ALLOW AN INCREASE TO 60 PERCENT ACROSS THE WEST
FOR LATE TONIGHT.
THE UPPER LEVEL LOW FROM THE SOUTHWEST IS THEN EXPECTED TO MOVE
ACROSS THE AREA MONDAY INTO MONDAY NIGHT BRINGING MODERATE TO
STRONG PV ADVECTION IN THE 500-300 MB ACROSS THE AREA. THE QG
CONVERGENCE WILL BECOME DEEP THROUGH THE 1000-300 MB LAYER AND
SHOULD BE MODERATE IN STRENGTH. THE ISENTROPIC UP GLIDE AHEAD OF
THE LOW WILL ALSO INCREASE WITH THE GFS SHOWING UP TO 10 UBAR/S ON
THE 290K SURFACE BY MONDAY AFTERNOON. WITH THE INCREASED
FORCING...EXPECT THE PRECIPITATION TO BECOME PRETTY WIDESPREAD AND
WILL HAVE 70 TO 80 PERCENT CHANCES FOR THE ENTIRE AREA.
TEMPERATURES WILL CONTINUE TO BE WARM ENOUGH TO KEEP THIS AS ALL
RAIN. THE FORCING WILL NOT START TO DECREASE UNTIL LATE MONDAY
NIGHT...SO WILL CONTINUE WITH THE HIGH PRECIPITATION CHANCES UNTIL
DROPPING THEM DOWN TO ABOUT 60 PERCENT IN THE SOUTHWEST BY LATE
MONDAY NIGHT. BY THIS TIME...THE SURFACE WILL HAVE PASSED BY THE
REGION ALLOWING COLDER AIR TO SPREAD ACROSS THE REGION. THIS WILL
ALLOW FOR A TRANSITION OVER TO SNOW MONDAY NIGHT INTO TUESDAY
MORNING. NOT EXPECTING ANY MIXED PRECIPITATION ISSUES WITH ICE
REMAINING IN THE CLOUDS UNTIL THE PRECIPITATION COMES TO AN END.
SNOWFALL AMOUNTS NOT EXPECTED TO A WHOLE LOT WITH MAYBE UP TO A
HALF INCH OF ACCUMULATION FOR PORTIONS OF SOUTHEAST MINNESOTA
INTO NORTH CENTRAL WISCONSIN.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 255 AM CST SUN DEC 14 2014
FINALLY STARTING TO SEE A CONSENSUS BETWEEN THE MODELS WITH HOW
THE CANADIAN UPPER LEVEL LOW IS HANDLED. THE GFS LOOKS TO HAVE
COME AROUND TO SHOWING THE SAME EVOLUTION THAT THE ECMWF HAS BEEN
SHOWING FOR SEVERAL RUNS. THE UPPER LEVEL LOW IS EXPECTED TO COME
DOWN OVER THE NORTHERN GREAT LAKES TUESDAY NIGHT AND CONTINUE TO
BE PROGRESSIVE AND MOVE OFF THE NORTHEAST COAST THURSDAY NIGHT.
THIS WILL ALLOW HIGH PRESSURE TO BUILD IN AT THE SURFACE BEHIND
THE EARLY WEEK SYSTEM AND THEN REMAIN OVER THE UPPER MIDWEST FOR
THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 528 AM CST SUN DEC 14 2014
THE PERSISTENT FLOW OF GULF OF MEXICO MOISTURE INTO COOLER AIR
OVER THE TAF SITES CONTINUES TO PRODUCE FOG AND STRATUS. CEILINGS
ARE STUCK AT LIFR WHILE VISIBILITIES ARE HOLDING AT VLIFR AT RST
AND IFR AT LSE. ANTICIPATING LITTLE CHANGE IN THESE CONDITIONS
DURING THE MORNING. DAYTIME HEATING MAY...UNDERSCORE MAY...IMPROVE
CONDITIONS A LITTLE FOR THE AFTERNOON. BROUGHT RST UP TO LIFR IN
VISIBILITY...AND AT LSE MVFR IN VISIBILITY AND IFR IN CEILING...
BASED ON WHAT HAPPENED YESTERDAY. HOWEVER...RST COULD EASILY STAY
STUCK AT VLIFR IN VISIBILITY THE WHOLE AFTERNOON. CONDITIONS WILL
GO DOWNHILL AGAIN TONIGHT WITH SLIGHTLY LIGHTER WINDS PROGGED AND
THE FLOW OF MOISTURE CONTINUING.
LOOKING AHEAD...A BRIEF REPRIEVE FROM THE POOR VISIBILITIES IS
POSSIBLE DURING THE LATE MORNING AND AFTERNOON ON MONDAY AS RAIN
MOVES THROUGH THE TAF SITES. STILL...ONCE THE RAIN TAILS OFF...IT
LOOKS TO BE BACK IN THE THICK FOG. SOMETIME BETWEEN 05-10Z TUESDAY
APPEARS TO BE WHEN THE FOG WILL FINALLY BEGIN TO EXIT THE TAF
SITES.
&&
.CLIMATE...
ISSUED AT 255 AM CST SUN DEC 14 2014
UNSEASONABLY MILD AIR REMAINS OVER THE AREA TODAY. THE RECORD HIGH
AT ROCHESTER IS 52 AND 56 FOR LA CROSSE. WHILE IT DOES NOT LOOK
LIKE LA CROSSE WILL COME CLOSE TO SETTING A RECORD...IT WILL BE
VERY CLOSE FOR ROCHESTER WITH A CURRENT FORECAST OF 51. THE
CLOUDY SKIES AND FOG MAY END UP BEING THE LIMITING FACTOR IF
TEMPERATURES DO NOT WARM AS MUCH AS EXPECTED.
ON THE OTHER HAND...RECORD WARM LOWS ARE ALL BUT CERTAIN FOR
TODAY. THE CURRENT RECORD WARM LOW AT ROCHESTER IS 37 SET IN 1928
WHILE LA CROSSE IS 41 SET IN 1891. THE CURRENT EXPECTATION IS THAT
TEMPERATURES WILL REMAIN IN THE 40S THROUGH MIDNIGHT TONIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL NOON CST MONDAY FOR WIZ017-029-032>034-
041>044-053>055-061.
MN...DENSE FOG ADVISORY UNTIL NOON CST MONDAY FOR MNZ079-086>088-
094>096.
IA...DENSE FOG ADVISORY UNTIL NOON CST MONDAY FOR IAZ008>011-018-019-
029-030.
&&
$$
UPDATE...DAS
SHORT TERM...04
LONG TERM...04
AVIATION...AJ
CLIMATE...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
528 AM CST SUN DEC 14 2014
.UPDATE...
ISSUED AT 528 AM CST SUN DEC 14 2014
BECOMING VERY CONCERNED THAT THE DENSE FOG ADVISORY MAY NEED TO BE
EXTENDED FOR THE ENTIRE FORECAST AREA...POSSIBLY INTO MONDAY.
WITH UPPER 40S AND LOW TO MID 50S DEWPOINTS LURKING SOUTH OF THE
AREA NEAR I-80 BEING SHOVED NORTHWARD INTO OUR RELATIVELY SPEAKING
COLDER AIRMASS...ITS POSSIBLE THIS DENSE FOG GOES NOWHERE. ON TOP
OF THAT...LIGHTER WINDS ARE PROGGED TONIGHT...FAVORING LOW
VISIBILITIES. 14.10Z LAV GUIDANCE AT MOST SITES THAT ARE CURRENTLY
EXPERIENCING 1/4 MILE OR LESS VISIBILITIES...SUCH AS RST...CCY AND
MDZ...SHOWS THOSE VISIBILITIES PERSISTING THROUGH 11Z MONDAY...THE
END OF ITS RUN. WE MAY END UP HAVING TO WAIT FOR THE RAIN ON
MONDAY TO HELP IMPROVE VISIBILITIES SOMEWHAT...THOUGH DENSE FOG
COULD EASILY REFORM AFTER THE RAIN TAILS OFF. SOMETIME AFTER
MIDNIGHT MONDAY NIGHT APPEARS WHEN WE CAN FINALLY GET RID OF THE
FOG CONCERN...ACCOMPANYING THE COLD ADVECTION REGIME DEVELOPING
THEN.
HAVE NOT DONE ANY EXTENSIONS TO THE CURRENT ADVISORY...BUT THEY
COULD HAPPEN AT ANYTIME THROUGHOUT THE MORNING. THE HIGHEST
CONFIDENCE FOR THE DENSE FOG TO PERSIST IS ACROSS TAYLOR AND
CLARK COUNTIES...WHICH COINCIDES WITH THE COLDEST FORECAST
READINGS.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 255 AM CST SUN DEC 14 2014
THE MAIN FORECAST CONCERN CONTINUES TO BE THE PRECIPITATION
CHANCES THROUGH THE PERIOD.
LOCAL OBSERVATIONS CONTINUE TO SHOW DENSE FOG WITH VISIBILITIES OF
A QUARTER MILE OR LESS COVERING A GOOD SHARE OF THE AREA. THE
14.05Z RAP BUFKIT SOUNDINGS SUGGEST THE WINDS JUST ABOVE THE
SURFACE MAY DIMINISH A LITTLE BIT THROUGH THE REST OF THE NIGHT
INTO SUNDAY MORNING WITH A SLOWLY DEEPENING SATURATED LAYER. THIS
MAY ALLOW THE DENSE FOG TO BECOME A LITTLE MORE WIDESPREAD AND FOR
THE AREAS THAT HAVE DECENT VISIBILITY TO GO DOWN SOME. PLAN TO
LEAVE THE DENSE FOG ADVISORY IN PLACE WITH NO CHANGES.
STILL DEALING WITH THE ISSUE OF HOW MUCH IF ANY DRIZZLE IS
OCCURRING WITH THE FOG. BASED ON PERSONAL OBSERVATIONS...MUCH LESS
DRIZZLE WAS OCCURRING IN THE LOCAL AREA SATURDAY EVENING THAN
PREVIOUS NIGHTS. THE RAP CONTINUES TO SUGGEST THAT WHAT OMEGA
THERE WILL BE IN THE SATURATED LAYER WILL BE VERY NEAR THE TOP OF
THIS LAYER. THE 14.00Z GFS ALSO CONTINUES TO SHOW JUST SOME VERY
WEAK ISENTROPIC UP GLIDE OF 1 UBAR/S OR LESS ON THE 290K SURFACE.
WILL MAINTAIN THE MENTION OF DRIZZLE FOR THE ENTIRE DAY...BUT WILL
LOWER THE PRECIPITATION CHANCES OF MEASURABLE DOWN TO THE 2O TO 30
PERCENT RANGE. THIS WILL ALSO GIVE AREAS INSTEAD OF WIDESPREAD
DRIZZLE WHICH MOST LIKELY WILL BETTER FIT THE SCENARIO AS WELL.
THE MAIN PRECIPITATION EVENT STILL LOOKS TO MONDAY AND MONDAY
NIGHT. THE UPPER LEVEL LOW LIFTING OUT OF THE DESERT SOUTHWEST IS
EXPECTED TO MOVE INTO THE LOWER MISSOURI RIVER VALLEY TONIGHT AS
ANOTHER UPPER LEVEL LOW DROPS SOUTH FROM CENTRAL CANADA. EVEN
THOUGH THE MAIN UPPER LEVEL RIDGE WILL BE OVER THE EASTERN
CONUS...THE GFS SUGGESTS A SECONDARY RIDGE AXIS WILL EXTEND OFF
THE MAIN RIDGE AXIS ACROSS THE UPPER MIDWEST BETWEEN THE TWO UPPER
LEVEL LOWS. THIS WOULD KEEP THE MAJORITY OF THE FORCING AWAY FROM
THE AREA WITH THE GFS SUGGESTING JUST SOME WEAK QG CONVERGENCE
OCCURRING ACROSS THE WESTERN SECTIONS OF THE AREA WITH JUST THE
VERY WEAK ISENTROPIC UP GLIDE CONTINUING ON THE 290K SURFACE. WILL
TRIM THE RAIN CHANCES BACK TO THE 20 TO 40 PERCENT RANGE FOR THE
EVENING AND THEN ALLOW AN INCREASE TO 60 PERCENT ACROSS THE WEST
FOR LATE TONIGHT.
THE UPPER LEVEL LOW FROM THE SOUTHWEST IS THEN EXPECTED TO MOVE
ACROSS THE AREA MONDAY INTO MONDAY NIGHT BRINGING MODERATE TO
STRONG PV ADVECTION IN THE 500-300 MB ACROSS THE AREA. THE QG
CONVERGENCE WILL BECOME DEEP THROUGH THE 1000-300 MB LAYER AND
SHOULD BE MODERATE IN STRENGTH. THE ISENTROPIC UP GLIDE AHEAD OF
THE LOW WILL ALSO INCREASE WITH THE GFS SHOWING UP TO 10 UBAR/S ON
THE 290K SURFACE BY MONDAY AFTERNOON. WITH THE INCREASED
FORCING...EXPECT THE PRECIPITATION TO BECOME PRETTY WIDESPREAD AND
WILL HAVE 70 TO 80 PERCENT CHANCES FOR THE ENTIRE AREA.
TEMPERATURES WILL CONTINUE TO BE WARM ENOUGH TO KEEP THIS AS ALL
RAIN. THE FORCING WILL NOT START TO DECREASE UNTIL LATE MONDAY
NIGHT...SO WILL CONTINUE WITH THE HIGH PRECIPITATION CHANCES UNTIL
DROPPING THEM DOWN TO ABOUT 60 PERCENT IN THE SOUTHWEST BY LATE
MONDAY NIGHT. BY THIS TIME...THE SURFACE WILL HAVE PASSED BY THE
REGION ALLOWING COLDER AIR TO SPREAD ACROSS THE REGION. THIS WILL
ALLOW FOR A TRANSITION OVER TO SNOW MONDAY NIGHT INTO TUESDAY
MORNING. NOT EXPECTING ANY MIXED PRECIPITATION ISSUES WITH ICE
REMAINING IN THE CLOUDS UNTIL THE PRECIPITATION COMES TO AN END.
SNOWFALL AMOUNTS NOT EXPECTED TO A WHOLE LOT WITH MAYBE UP TO A
HALF INCH OF ACCUMULATION FOR PORTIONS OF SOUTHEAST MINNESOTA
INTO NORTH CENTRAL WISCONSIN.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 255 AM CST SUN DEC 14 2014
FINALLY STARTING TO SEE A CONSENSUS BETWEEN THE MODELS WITH HOW
THE CANADIAN UPPER LEVEL LOW IS HANDLED. THE GFS LOOKS TO HAVE
COME AROUND TO SHOWING THE SAME EVOLUTION THAT THE ECMWF HAS BEEN
SHOWING FOR SEVERAL RUNS. THE UPPER LEVEL LOW IS EXPECTED TO COME
DOWN OVER THE NORTHERN GREAT LAKES TUESDAY NIGHT AND CONTINUE TO
BE PROGRESSIVE AND MOVE OFF THE NORTHEAST COAST THURSDAY NIGHT.
THIS WILL ALLOW HIGH PRESSURE TO BUILD IN AT THE SURFACE BEHIND
THE EARLY WEEK SYSTEM AND THEN REMAIN OVER THE UPPER MIDWEST FOR
THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 528 AM CST SUN DEC 14 2014
THE PERSISTENT FLOW OF GULF OF MEXICO MOISTURE INTO COOLER AIR
OVER THE TAF SITES CONTINUES TO PRODUCE FOG AND STRATUS. CEILINGS
ARE STUCK AT LIFR WHILE VISIBILITIES ARE HOLDING AT VLIFR AT RST
AND IFR AT LSE. ANTICIPATING LITTLE CHANGE IN THESE CONDITIONS
DURING THE MORNING. DAYTIME HEATING MAY...UNDERSCORE MAY...IMPROVE
CONDITIONS A LITTLE FOR THE AFTERNOON. BROUGHT RST UP TO LIFR IN
VISIBILITY...AND AT LSE MVFR IN VISIBILITY AND IFR IN CEILING...
BASED ON WHAT HAPPENED YESTERDAY. HOWEVER...RST COULD EASILY STAY
STUCK AT VLIFR IN VISIBILITY THE WHOLE AFTERNOON. CONDITIONS WILL
GO DOWNHILL AGAIN TONIGHT WITH SLIGHTLY LIGHTER WINDS PROGGED AND
THE FLOW OF MOISTURE CONTINUING.
LOOKING AHEAD...A BRIEF REPRIEVE FROM THE POOR VISIBILITIES IS
POSSIBLE DURING THE LATE MORNING AND AFTERNOON ON MONDAY AS RAIN
MOVES THROUGH THE TAF SITES. STILL...ONCE THE RAIN TAILS OFF...IT
LOOKS TO BE BACK IN THE THICK FOG. SOMETIME BETWEEN 05-10Z TUESDAY
APPEARS TO BE WHEN THE FOG WILL FINALLY BEGIN TO EXIT THE TAF
SITES.
&&
.CLIMATE...
ISSUED AT 255 AM CST SUN DEC 14 2014
UNSEASONABLY MILD AIR REMAINS OVER THE AREA TODAY. THE RECORD HIGH
AT ROCHESTER IS 52 AND 56 FOR LA CROSSE. WHILE IT DOES NOT LOOK
LIKE LA CROSSE WILL COME CLOSE TO SETTING A RECORD...IT WILL BE
VERY CLOSE FOR ROCHESTER WITH A CURRENT FORECAST OF 51. THE
CLOUDY SKIES AND FOG MAY END UP BEING THE LIMITING FACTOR IF
TEMPERATURES DO NOT WARM AS MUCH AS EXPECTED.
ON THE OTHER HAND...RECORD WARM LOWS ARE ALL BUT CERTAIN FOR
TODAY. THE CURRENT RECORD WARM LOW AT ROCHESTER IS 37 SET IN 1928
WHILE LA CROSSE IS 41 SET IN 1891. THE CURRENT EXPECTATION IS THAT
TEMPERATURES WILL REMAIN IN THE 40S THROUGH MIDNIGHT TONIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR WIZ017-029-032>034-
041>044-053>055-061.
MN...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR MNZ079-086>088-
094>096.
IA...DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR IAZ008>011-018-019-
029-030.
&&
$$
UPDATE...AJ
SHORT TERM...04
LONG TERM...04
AVIATION...AJ
CLIMATE...04
AREA FORECAST DISCUSSION
NWS PUEBLO CO
306 PM MST SUN DEC 14 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 306 PM MST SUN DEC 14 2014
THE UPR LOW IS MOVING INTO THE FAR SWRN CORNER OF KS THIS
AFTERNOON...WITH SOME THUNDERSTORMS CONTINUING OVER PORTIONS OF THE
SERN CO PLAINS. SATELLITE IMAGES SHOW THAT DRY AIR HAS WRAPPED INTO
THE ERN CO BORDER AREA...WITH THE TSTMS BEING ON THE WRN
EDGE...MAINLY OVR BENT COUNTY. TEMPS OVR THE SERN PLAINS ARE MOSTLY
IN THE 40S...WITH LOWER 50S NR THE KS BORDER. ALONG THE I-25
CORRIDOR TEMPS ARE IN THE 30S WITH PERIODS OF RAIN...SOMETIMES MIXED
WITH SNOW...EXCEPT OVR NRN PORTIONS OF EL PASO COUNTY WHERE TEMPS
ARE A LITTLE COLDER AND THE PCPN IS IN THE FORM OF SNOW. THOUGH WEB
CAMS SHOW ONLY LIGHT ACCUMULATIONS ON GRASSY AREAS OVR NRN EL PASO
COUNTY.
THE CURRENT POSITION OF THE UPR LOW IS WRAPPING THE BEST MSTR INTO
NERN CO. THE LOW IS FORECAST TO TRACK ENE TONIGHT...WITH MSTR
CONTINUING TO WRAP AROUND INTO ERN CO INTO THE LATE NIGHT HOURS.
THE NAM AND RUC ALSO CONTINUE TO SHOW HEAVY SNOW ACCUMULATIONS THIS
EVENING OVR PORTIONS OF THE FAR SERN CO PLAINS...WHICH IS WORRISOME
BUT AM SURE THIS IS OVERDONE. AS THE TEMPS COOL THIS EVENING OVR THE
FAR SERN PLAINS PCPN SHOULD CHANGE OVR TO SNOW...BUT IT WL TAKE
AWHILE FOR THE TEMPS TO COOL NR THE ERN BORDER. HAVE DECIDED TO PUT
A COUPLE INCHES OF SNOW IN THE FORECAST FOR SOME PORTIONS OF THE
SERN PLAINS THIS EVENING...BUT THERE IS A LOT OF UNCERTAINTY.
ELSEWHERE...WEB CAMS ARE NOT SHOWING MUCH IN MOST AREAS IN THE WAY
OF SNOWFALL AND ACCUMULATIONS. LIGHT SNOW IS STILL EXPECTED OVR THE
SANGRES THIS EVENING...BUT IT LOOKS LIKE SIGNIFICANT ACCUMS WL NOT
LONGER OCCUR AND WL THEREFORE CANCEL THE ADVISORY FOR THAT AREA WITH
THE AFTERNOON FORECAST ISSUANCE. WL ALSO CANCEL THE ADVISORY FOR
THE LEADVILLE AREA...BUT WL KEEP THE ADVISORY FOR THE SAWATCH AND
MOSQUITO RANGES GOING TO 01Z.
FOR LATE TONIGHT...AS THE UPR LOWS CONTINUES MOVING AWAY FROM THE
AREA...PCPN OVR THE SERN PLAINS WL BE ON THE DECREASE AND SHOULD
MOSTLY BE OVR BY MON MORNING. THE NW FLOW ALOFT WL KEEP SOME ISOLD
TO SCT SNOW SHOWERS GOING THRU THE NIGHT AND INTO MON MORNING OVR
THE CENTRAL CO MTNS...BUT ONLY LIGHT ADDITIONAL ACCUMULATIONS ARE
EXPECTED. WITH DECREASING CLOUDS TONIGHT IN THE SAN LUIS
VALLEY...SOME LOW CLOUDS AND FOG MAY DEVELOP.
MONDAY WL GENERALLY BE A DRY DAY WITH HIGHS BEING CLOSE TO AVERAGE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 306 PM MST SUN DEC 14 2014
.TUESDAY AND WEDNESDAY...DISTURBANCE MOVES ONSHORE TUESDAY AND
INTO COLORADO ON WEDNESDAY. SYSTEM WEAKENS AS IT APPROACHES
COLORADO AND IT IS MOVING RELATIVELY FAST. GRIDS HAVE INCREASING
POPS OVER THE MOUNTAINS ON WEDNESDAY...ESPECIALLY THE CONTINENTAL
DIVIDE REGION. AT THIS TIME...IT APPEARS AMOUNTS WILL LIKELY
REMAIN BELOW ADVISORY CRITERIA. WEAK UPSLOPE ONE THE PLAINS WILL
TEND TO KEEP TEMPERATURES NEAR SEASONAL VALUES DESPITE SOME
WARMING ALOFT.
.THURSDAY AND FRIDAY...SECOND...STRONGER TROUGH IS FORECAST TO
MOVE ONSHORE WEDNESDAY NEAR NORTHERN CALIFORNIA AND MOVE
SOUTHEAST. MOST OF THE MODELS AND ENSEMBLE MEMBERS HAVE THE TROUGH
MOVING ACROSS SOUTHERN NEW MEXICO ON THURSDAY. THIS TRACK KEEP
MUCH OF THE HEAVIER PRECIPITATION SOUTH OF THE STATE. GFS AND EC
SUGGEST A MUCH WEAKER DISTURBANCE MAY MOVE ACROSS NORTHERN
COLORADO. GFS AND EC PRINT SOME LIGHT QPF ON THE PLAINS
THURSDAY...ASSOCIATED WITH SOME WEAK UPSLOPE FLOW. DECIDED TO ADD
SOME ISOLATED POPS ON THE PLAINS...WHICH MATCHES SURROUNDING
OFFICES BETTER. IF THE CURRENT PATH OF THE STRONGER DISTURBANCE
REMAINS WELL SOUTH OF COLORADO...ANTICIPATE ANY PRECIPITATION ON
THE PLAINS AND EASTERN MOUNTAINS WILL BE LIGHT.
.SATURDAY AND SUNDAY...NEXT DISTURBANCE MOVES ONSHORE LATE FRIDAY
AND SLOWLY MOVES SOUTHEAST. THE 12Z GFS HAS AN INTERESTING
SOLUTION WITH THE CUTOFF PASSING OVER THE FOUR CORNERS REGION.
THIS PATH COULD BRING SNOW TO MUCH OF THE CWA. EC AND A FAIR
NUMBER OF ENSEMBLES MEMBERS HAVE THE CUTOFF MOVING FURTHER SOUTH
AND WEST...REMAINING WELL SOUTH OF COLORADO. THIS SOLUTION WOULD
LIMIT SNOWFALL AMOUNTS IN THE CWA. --PGW--
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 306 PM MST SUN DEC 14 2014
KALS SHOULD HAVE VFR CONDITIONS TONIGHT AND MONDAY...HOWEVER THERE
IS THE POTENTIAL FOR SOME LOW STRATUS AND FOG TO DEVELOP LATE
TONIGHT INTO EARLY MONDAY...BUT NOT CONFIDENT ENOUGH TO PUT IN THE
TERMINAL FORECAST.
KCOS WL STILL HAVE SOME SNOW SHOWERS IN THE VCNTY THIS EVENING AND
COULD HAVE PERIODS OF MVFR CONDITIONS IN SHOWERS...OTHERWISE VFR
CONDITIONS ARE EXPECTED TONIGHT AND MONDAY.
KPUB WL HAVE VFR CONDITIONS TONIGHT AND MONDAY...ALTHOUGH THERE WILL
STILL BE SOME SHOWERS IN THE VCNTY THIS EVENING AND THERE IS THE
POTENTIAL FOR SOME BRIEF MVFR CONDITIONS IN SHOWERS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 PM MST THIS EVENING FOR COZ058-
060.
&&
$$
SHORT TERM...28
LONG TERM...PGW
AVIATION...28
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
304 PM CST SUN DEC 14 2014
.SHORT TERM...
302 PM CST
TONIGHT THROUGH MONDAY...
CLOUDY AND OVERALL DREARY WEATHER CONTINUES ACROSS THE REGION
TODAY...HOWEVER WARMER TEMPERATURES ARE IN PLACE AND WILL CONTINUE
THROUGH TOMORROW AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM.
LOW PRESSURE IS TAKING SHAPE OVER THE OK/TX PANHANDLE REGION TODAY
AS A CLOSED UPPER LOW AND AMPLIFIED LONGWAVE TROUGH EMERGE OVER THE
PLAINS STATES. MUCH OF THE SAME IS IN STORE AHEAD OF THIS SYSTEM REST
OF TODAY AND TONIGHT WITH OVERCAST CONDITIONS...SOME FOG...AND
OCCASIONAL DRIZZLE. TEMPERATURES WONT FALL OFF TONIGHT WITH WARM
ADVECTION AND DEWPOINTS IN THE MID 40S. RAIN CHANCES WILL RAMP UP
MID TO LATE MORNING MONDAY ACROSS THE WEST/SOUTHWEST COUNTIES...THEN
BY EARLY/MID AFTERNOON FOR THE CHICAGO AREA AS LEAD UPPER SHORTWAVE
EJECTS AHEAD OF THE UPPER LOW COINCIDING WITHIN A CORRIDOR OF
MODERATE WARM AIR ADVECTION THAT WILL LIFT NORTHEAST ACROSS THE
FORECAST AREA. FORECAST SOUNDINGS DO HINT AS SOME VERY MODEST
INSTABILITY AT TIMES WITH THIS LEAD WAVE WITH LAPSE RATES ABOVE
AROUND H6 OR SO NEAR MOIST ADIABATIC. PROBABILITY OF TAPPING INTO
THIS SEEMS REALLY LOW SO WONT INTRODUCE ANYTHING INTO GRIDS AT THIS
TIME...BUT WOULDNT BE SURPRISED IF THERE WERE ANY ISOLATED
EMBEDDED HEAVIER SHOWERS OR THUNDERSTORMS.
DEUBELBEISS
&&
.LONG TERM...
302 PM CST
MONDAY NIGHT THROUGH SUNDAY...
VERTICALLY STACKED OCCLUDED LOW LIFTS SLOWLY NORTHEAST ACROSS THE
AREA MONDAY NIGHT THROUGH TUESDAY. INITIAL BAND OF RAIN WHICH
SPREADS ACROSS THE AREA DURING THE DAY MONDAY WILL BE LIFTING
NORTHEAST AND WEAKENING DURING THE EVENING...AS STRONGEST LOW LEVEL
MOISTURE TRANSPORT BECOMES FOCUSED ACROSS THE OHIO VALLEY NEAR THE
TRIPLE POINT OF THE SURFACE OCCLUSION. GUIDANCE IN GENERAL AGREEMENT
THAT A SECONDARY COLD FRONT INITIALLY OVER THE UPPER MISSISSIPPI
VALLEY WILL BECOME A SECONDARY FOCUS FOR PRECIPITATION...BENEATH
UPPER LOW CENTER AND ALONG WARM SIDE OF LOW LEVEL FRONTOGENESIS
MAXIMA WITH SECONDARY FRONT. THUS HAVE GENERALLY FOLLOWED HIGHER
MODEL POPS FOR MONDAY NIGHT. STACKED CIRCULATION PASSES ACROSS
NORTHEAST ILLINOIS AND SOUTHERN LAKE MICHIGAN EARLY TUESDAY MORNING
AND TAKING THE STEADIEST PRECIPITATION ALONG WITH IT. LOW LEVEL COLD
AIR THEN SPREADS IN SMARTLY IN ITS WAKE...WITH ANY LINGERING LIGHT
RAIN MIXING WITH OR CHANGING TO SOME LIGHT SNOW FROM THE WEST FROM
MID-MORNING THROUGH THE AFTERNOON. LITTLE IN THE WAY OF QPF BY THIS
TIME AND FORECAST SOUNDING PROFILES APPEAR SOMEWHAT MARGINAL FOR ANY
SIGNIFICANT SNOW...EITHER DUE TO MOIST LOW LEVEL THERMAL PROFILES
NEAR FREEZING OR EROSION OF MID-LEVEL MOISTURE PREVENTING EFFECTIVE
ICE NUCLEATION ESPECIALLY DURING THE AFTERNOON. IN EITHER CASE...
LIGHT SNOW/RAIN MIX WITH NO ACCUMULATION APPEARS SUITABLE AT THIS
TIME. PERHAPS OF MORE IMPACT WILL BE A FALLING TEMPERATURE TREND...
AS THE WARMEST LOW LEVEL AIR AHEAD OF THE SURFACE LOW WILL HAVE
PRE-DAWN TEMPS IN THE LOW-MID 40S...THEN FALLING INTO THE 30S DURING
THE MORNING AND MID-DAY HOURS AS THE LOW AND SECONDARY COLD FRONT
MOVE EAST. TO ADD TO THE CHILL...WINDS WILL QUICKLY BECOME BLUSTERY
FROM THE WEST-NORTHWEST NEAR 30 MPH...SENDING WIND CHILL READINGS
INTO THE LOW-MID 20S BY LATE AFTERNOON. THE COLDER AND MUCH DRIER
AIR DOES LOOK TO QUICKLY BRING AN END TO ANY LINGERING LIGHT SNOW BY
EVENING...EXCEPT FOR A FEW LIGHT LAKE EFFECT SNOW SHOWERS WHICH
COULD CLIP NORTHEAST PORTER COUNTY TUESDAY NIGHT. SHALLOW
EQUILIBRIUM HEIGHTS...BELOW 5000 FT...SHOULD PRECLUDE ANY
SIGNIFICANT ACCUMULATION THERE.
THE SECOND HALF OF THE WEEK FROM WEDNESDAY THROUGH FRIDAY LOOK TO BE
SEASONABLY COOL AND SOMEWHAT BLUSTERY...AS A SECOND CLOSED MID-LEVEL
LOW DEVELOPS WITHIN ELONGATED WEST-EAST TROUGH FROM MINNESOTA AND
WISCONSIN EAST ACROSS THE LAKES. MEDIUM-RANGE OF GFS/ECMWF RUNS BOTH
INDICATE A LITTLE SHORT WAVE PIVOTING SOUTHEAST ACROSS THE AREA
WEDNESDAY AFTERNOON OR EVENING...THOUGH SOUNDINGS AND TIME/HEIGHT
PLOTS SHOW VERY DRY MID-LEVEL AIR AND NO QPF IS PRODUCED. OTHERWISE
HIGH PRESSURE SLOWLY BUILDS INTO THE AREA BY FRIDAY WITH DAYTIME
HIGHS NEAR FREEZING AND OVERNIGHT MINS IN THE TEENS AND LOWER 20S
ARE EXPECTED...AT OR JUST A BIT BELOW AVERAGE.
BY THE WEEKEND...ATTENTION TURNS TO AN UPPER LEVEL TROUGH PROJECTED
TO BE MOVING ACROSS THE DESERT SOUTHWEST AND SOUTHERN PLAINS...WITH
DEEP SURFACE LOW DEVELOPMENT DEPICTED ACROSS EAST TEXAS OR THE GULF
COAST FRIDAY. UPPER TROUGH THEN LIFTS NORTHEAST FRIDAY NIGHT AND
SATURDAY AND TAKES ON A SOMEWHAT NEGATIVE-TILT...WITH THE SURFACE
LOW DEEPENING AND ALSO MOVING EAST-NORTHEAST. CONSIDERABLE SPREAD IS
NOTED IN THE GUIDANCE LOW TRACKS BY THIS TIME...WITH THE ECMWF
FAVORING A MORE SOUTHERN ROUTE ACROSS THE SOUTHEAST AND TO THE
MID-ATLANTIC COAST BY SATURDAY NIGHT. THE 12Z PARALLEL 13 KM GFS
ALSO TAKES THE LOW SIMILARLY TO THE CAROLINA COAST...WHILE THE
CURRENT OPERATIONAL GFS AND A FEW GEFS ENSEMBLE TAKE THE LOW
NORTHEAST ACROSS LAKE ERIE AND LAKE ONTARIO BY SUNDAY MORNING. THIS
WOULD OBVIOUSLY HAVE IMPLICATIONS ON THE NORTHERN EXTENT OF THE
SYSTEM PRECIP SHIELD...WITH THE SOUTHERN TRACK LIKELY NOT BRINGING
PRECIP INTO THE AREA AT ALL...WHILE THE CURRENT OUTLYING NORTHERN
TRACKS COULD BRING MEASURABLE SNOW TO OUR SOUTHERN CWA. FOR DAY 7 AT
THIS GREAT DISTANCE WILL MAINTAIN SLIGHT CHANCE POPS FOR SNOW ACROSS
MAINLY THE SOUTHERN 2/3 OF CWA...BUT EVOLUTION OF NEXT WEEKENDS
SYSTEM WILL UNDOUBTEDLY DIFFER AND WILL HAVE TO BE CONTINUALLY
EVALUATED.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* IFR CIGS AT ORD AND MVFR AT MDW. MVFR VSBY. EXPECT STEADY STATE
THIS AFTERNOON...POSSIBLY SOME DECAY THROUGH THE EARLY
AFTERNOON.
* CIGS/VSBYS POTENTIALLY DROPPING AGAIN TONIGHT.
* SOUTHEAST WINDS TOPPING 10 KT LATER MONDAY MORNING.
KMD
//DISCUSSION...UPDATED 20Z...
UPSTREAM OBS SHOWING VERY LITTLE IMPROVEMTN IN THE COMING
HOURS...THEREFORE EXPECT CIGS AND VSBYS IN THE NEXT FEW HOURS TO
REMAIN THE SAME OR POSSIBLY GET WORSE. THERE COULD BE SOME SLIGHT
IMPROVEMENT LATE AFTERNOON BEFORE THINGS PROGRESS DOWNWARD AGAIN
OVERNIGHT...BUT CONFIDENCE BEYOND THE NEAR TERM ON SPECIFICS IS LOW.
PREVIOUS DISCUSSION...FROM 18Z...
MINIMAL TO VERY SLOW IMPROVEMENT HAS BEEN OCCURRING IN RECENT
HOURS...BUT CONTINUED MOIST ADVECTION INTO THE AREA HAS MAINTAINED
THE STATUS QUO WITH LIFR CEILINGS AND IFR/LIFR VSBYS ...WITH IFR
CIGS CLOSER TO CHICAGO...THEN IN THE IMMEDIATE CHICAGO
AREA...INCLUDING KMDW...DEWPOINT DEPRESSIONS REMAINED HIGHER
THROUGH THE MORNING KEEPING A POCKET OF MIXED MVFR/VFR CIGS CLOSE
TO THE LAKE...THOUGH THERE IS LIKELY SOME HAZE AND BR MIXED IN
BASED ON DOWNTOWN WEBCAMS.
DO STILL SHOW SOME GRADUAL IMPROVEMENT LATER THIS AFTERNOON AS WE
MIX A TOUCH MORE TODAY...BUT LITTLE MORE THAN IFR HAS OCCURRED
UPSTREAM UNTIL YOU GET TO THE CLEARING LINE DRAPING THE IL/MO
BORDER AND ADVANCING NORTHEAST. THEREFORE HAVE TRENDED TOWARD
KEEPING IFR IN MANY SPOTS THIS AFTERNOON WITH THE BEST CHANCE FOR
MVFR CLOSER TO CHICAGO. RUC/HRRR WHICH DO NOT HAVE A SUPERB HANDLE
ON THE CLEARING LINE DO STILL KEEP IT OUT OF THE TERMINALS
TODAY....MAYBE BRINING IT AGAIN INTO THE WESTERN TERMINALS LATE
TONIGHT AS WAS SEEN THIS MORNING AND POSSIBLY CLOSER INTO CHICAGO.
TIMING OF THIS CHALLENGING AND IF IT OCCURS WHAT IMPACTS THAT WILL
HAVE...SO FOR NOW HAVE KEPT THE SAME TRENDS.
OF CONCERN FOR TOMORROW...CIGS MAY LIFT SOME AS MIXING INCREASES
IN THE MORNING...BUT THEN HOLD AT MVFR OR WORSE FOR THE AFTERNOON AS RAIN
MOVES THROUGH. AT THIS TIME WINDS WILL BE OUT OF THE SE AND 10 KT
OR HIGHER.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH IN IFR CIGS FOR ORD...HIGH FOR MVFR AND MEDIUM ON TRENDING
TOWARD IFR THIS AFTERNOON.
* LOW IN CIG/VISBYS TONIGHT.
* MEDIUM-HIGH IN SE WINDS AT OR ABOVE 10 KT TOMORROW LATE MORNING-
AFTERNOON.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...IFR AND RAIN. SOUTH-SOUTHEAST WINDS.
TUESDAY...MVFR WITH IFR POSSIBLE. CHANCE OF RAIN IN THE MORNING
AND CHANCE OF RAIN/SNOW IN THE AFTERNOON. NORTHWEST
WINDS.
WEDNESDAY-THURSDAY...VFR LIKELY. NORTHWEST WINDS.
FRIDAY...MVFR POSSIBLE. NORTHEAST WINDS.
FRIDAY NIGHT-SATURDAY...MVFR POSSIBLE. SLGT CHANCE OF SNOW. NORTHEAST
WINDS.
MTF
&&
.MARINE...
207 PM CST
FEW CONCERNS IN THE IMMEDIATE NEAR TERM...AS WINDS ACROSS LAKE
MICHIGAN ARE GENERALLY SOUTH LESS THAN 20 KT THIS AFTERNOON. THIS
WILL CHANGE OVER THE NEXT 24-36 HOURS...AS AN AREA OF LOW PRESSURE
OVER THE OKLAHOMA PANHANDLE LIFTS SLOWLY NORTHEAST INTO MISSOURI ON
MONDAY...AND ACROSS THE FAR SOUTH END OF LAKE MICHIGAN LATE MONDAY
NIGHT INTO EARLY TUESDAY MORNING. AS THE LOW APPROACHES MONDAY...
SOUTH WINDS WILL INCREASE INTO THE 20-25 KT RANGE PARTICULARLY ON
THE SOUTHERN HALF OR SO OF THE LAKE...BEFORE TURNING NORTH-NORTHWEST
AND INCREASING TO 30 KT ON TUESDAY AS THE LOW PULLS AWAY TO THE EAST
AND COLDER AIR SPREADS INTO THE REGION. WHILE THE LOW MOVES AWAY AND
WINDS BEGIN TO DECREASE SLIGHTLY...A SURFACE TROUGH WILL LINGER
ACROSS THE WESTERN LAKES AND UPPER MIDWEST WHICH WILL MAINTAIN A
FAIRLY TIGHT NORTHWESTERLY GRADIENT AND WILL HELP KEEP WINDS GUSTY
ABOVE 20 KTS THROUGH WEDNESDAY. NORTHWEST WINDS WILL THEN DIMINISH
MORE NOTICEABLY DURING THE LATER PART OF THE WEEK...WITH HIGH
PRESSURE EVENTUALLY BUILDING INTO THE AREA FRIDAY. LONGER RANGE
MODEL FORECASTS INDICATE ANOTHER DEEP LOW PRESSURE SYSTEM MAY PASS
SOUTH OF THE LAKES NEXT WEEKEND.
RATZER
&&
.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:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
242 PM CST Sun Dec 14 2014
.SHORT TERM...(Tonight)
ISSUED AT 225 PM CST SUN DEC 14 2014
20z/2pm visible satellite imagery continues to show low clouds
blanketing much of central Illinois, with the exception being the
far southwest KILX CWA around Winchester. Large area of clearing
that developed over central/eastern Missouri earlier in the day has
worked its way northeastward and now extends along/southwest of a
Winchester to Mount Vernon line. Clearing has behaved much like the
HRRR has predicted, generally reaching the far SW CWA then coming to
a halt. Will continue to carefully monitor satellite trends to see
if clearing can make it any further northeast, but with the sun
going down soon, this does not seem likely. As a result, will
feature mostly clear skies across the far SW into the early evening
followed by a return to overcast conditions across the board.
Visibilities will be a big concern tonight, as current obs show some
sites already dropping into the 1-2 mile range. HRRR has
consistently shown visbys dropping below 1 mile by 00z, with patchy
dense fog possible after dark. Confidence is not great enough for
another Dense Fog Advisory at this time, but the potential certainly
exists as low-level moisture continues to increase and surface
dewpoints approach the 50 degree mark. Due to the clouds/fog,
overnight low temperatures will be several degrees above numeric
guidance in the middle to upper 40s. Vigorous upper-level low noted
on latest water vapor imagery over the Texas panhandle will begin to
lift northeastward tonight, with model consensus spreading showers
into the SW CWA after 3am, then to the I-55 corridor by 6am. Further
northeast, dry conditions will prevail across the E/NE CWA until
after dawn Monday morning.
&&
.LONG TERM...(Monday through Sunday)
ISSUED AT 225 PM CST SUN DEC 14 2014
Models in good agreement with the upper low pushing northeast into
Iowa by Monday afternoon with strong 850 mb theta-e advection/convergence
pointed right into west central Illinois in the 09z-12z time frame.
Highest POPs will be over west central Illinois during that time period
with a progressive shift east with the categorical POPs as the morning
wears on. May have some thunder in the precip band associated with
the warm conveyor belt in the morning, but mid level lapse rates really
don`t ramp up until the afternoon hours as the closed system at 500
mb approaches. Then it appears the better threat for thunder will be
over west central Illinois tomorrow afternoon which will be closest
to the closed 500 mb low. High resolution reflectivity simulations
suggest a band of showers sweeping across the area in the morning,
with a break late morning into the early afternoon hours, before
more showers push across the area as the upper low and deeper forcing
approaches. Will keep likely POPs going across the northern third
of the forecast area tomorrow evening, close to the track of the upper
wave, with POPs starting to decrease late Monday night into Tuesday
from southwest to northeast. The system should continue to push away
from our area on Tuesday with lingering POPs only in the far north
and east during the morning with colder air filtering into our area
as the surface low pushes into lower Michigan by late Tuesday afternoon.
The upper wave will merge with a northern stream shortwave with the
system slowly pulling off to our east thru the end of the week. High
pressure at the surface will shift slowly southeast across the northern
Plains while another piece of energy translates east across the
southern Plains late Wednesday into Thursday with its precipitation
shield possibly affecting southern Illinois during the day Thursday
into Thursday night. Still seeing varying solutions with the initial
wave coming out of the southwest and into the lower Mississippi
Valley late Wed thru late Thursday with the higher POPs continuing
over our far southern counties. Having a hard time seeing precip shift
too far north into a more confluent flow over the southern Great Lakes
with surface high pressure holding firm over the upper Midwest.
A second and stronger wave is then forecast to eject east and then
northeast across Texas on Friday with a large area of rain to its north.
The latest ECMWF, GEM global and UK models were more suppressed with
the low level baroclinic zone/frontal boundary, and as a result, are
more suppressed with the track of the surface low than the current
operational GFS. However, the high resolution GFS (not yet ready for
prime time model) suggests a more suppressed track as well with the
system late in the week. So will go with the consensus for the late
week system and keep any likely or higher POPs to our south late
Friday thru Saturday. The threat for precip will shift well off to
our east on Sunday as the storm system skirts around our area and
then heads up the East Coast later Saturday into Sunday while high
pressure settles into our area for Sunday.
After the unseasonably mild temperatures on Monday, colder temperatures
will filter back into the region starting on Tuesday and remain with
us through the rest of the period. We should see temperatures gradually
return closer to seasonal levels for the middle of December Tuesday
night and hold over the region thru the period.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1139 AM CST SUN DEC 14 2014
IFR conditions will prevail through the entire 18z TAF period. Low
clouds/fog currently blanket central Illinois, although visbys are
slowly improving. Will continue to monitor a large break in the
overcast across eastern Missouri that is lifting northeastward and
may reach the SW KILX CWA early this afternoon. Latest run of the
HRRR, as well as the 12z NAM keep the clearing well southwest of
the TAF sites, so have gone with a persistence forecast of
continued IFR ceilings. Visbys will improve to between 3 and 5sm
for a period this afternoon: however, all signs are pointing to
re-development of the fog tonight. Have dropped visbys back down
to around 1sm after 00z accordingly. Next storm system is still
slated to arrive later tonight into Monday morning. Based on
NAM/GFS, have introduced rain and an improvement in visbys by 11z
at KSPI, then further east to KCMI after 14z.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Smith
AVIATION...Barnes
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1206 PM CST SUN DEC 14 2014
.SHORT TERM...
TODAY THROUGH MONDAY NIGHT...
333 AM...FORECAST CONCERNS INCLUDE FOG THIS MORNING AND TONIGHT...
HIGH TEMPS TODAY AND MONDAY AND THEN RAIN MONDAY ALONG WITH THE
CHANCE OF THUNDER.
A BREAK IN THE CLOUDS THAT MOVED INTO WESTERN AND NORTHWEST IL A
FEW HOURS AGO IS QUICKLY SHRINKING AS IS ANOTHER BREAK ACROSS MO.
THUS...NOT MUCH CONFIDENCE TO STRAY FROM CLOUDY MENTION OVER THE
NEXT 48 HOURS WITH ANY BREAKS LIKELY BEING TOO SHORT-LIVED TO TRY
TO INCLUDE IN THE FORECAST. THIS BREAK DID ALLOW SOME RADIATIONAL
COOLING WITH TEMPS DIPPING INTO THE MID/UPPER 30S ACROSS THE FAR
WESTERN CWA WHICH AIDED SOME LOCALLY DENSE FOG. WITH CLOUDS
FILLING BACK IN AND TEMPS IN THESE AREAS SLOWLY WARMING...NOT
EXPECTING ANY WIDESPREAD DENSE FOG THIS MORNING BUT AREAS ALONG
THE WI BORDER BACK INTO FAR NORTHWEST IL WILL LIKELY SEE REDUCED
VISIBILITIES THROUGH MIDDAY.
HAD BEEN CARRYING DRIZZLE IN THE FORECAST THROUGH THIS MORNING
BUT LITTLE IN THE WAY OF OBSERVATIONS OF DRIZZLE AND CONFIDENCE
REGARDING ANY WIDESPREAD DRIZZLE DEVELOPING IS LOW ENOUGH TO
REMOVE IT.
WHERE CLOUDS HAVE REMAINED OVC...TEMPS HAVE REMAINED GENERALLY IN
THE MID 40S...THOUGH MAY DIP INTO THE LOWER 40S BY MORNING. EVEN
WITH THESE LOWS...HIGHS TODAY SHOULD BE ABLE TO REACH THE LOWER TO
MID 50S MOST AREAS AND DIDN/T MAKE ANY CHANGES TO THE GOING HIGHS
FOR TODAY.
CONFIDENCE FOR BOTH FOG AND DRIZZLE TONIGHT IS SOMEWHAT LOW.
GUIDANCE CONTINUES TO SUGGEST FOG MAY BECOME DENSE IN SOME AREAS
AND SOME AREAS/PATCHY FOG STILL EXTENDS WILL SOUTH INTO CENTRAL
IL/NORTHERN MO. IF FOG WERE TO BECOME DENSE...THEN THAT WOULD
LIKELY LEAD TO THE POTENTIAL FOR DRIZZLE. FOR NOW HAVE TRENDED A
BIT MORE OPTIMISTIC WITH JUST PATCHY FOG MENTION. LOWS TONIGHT MAY
ALSO BE FOG DEPENDENT...POSSIBLY DROPPING LOWER THAN ADVERTISED
MID 40S IF DENSE FOG DEVELOPS.
BULK OF ANY RAIN SHOULD HOLD OFF UNTIL AFTER DAYBREAK MONDAY
MORNING WITH A LINE/BAND OF SHOWERS MOVING NORTHEAST ACROSS THE
AREA WITH GOOD AGREEMENT FROM THE MODELS. ENOUGH INSTABILITY WITH
THIS THAT A RUMBLE OR TWO OF THUNDER IS POSSIBLE BUT AS IT MAY BE
IN A DECAYING STAGE AS IT ARRIVES...NOT CONFIDENT ENOUGH TO
INCLUDE ANY THUNDER MENTION. COULD BE SEVERAL DRY HOURS AHEAD AND
BEHIND THIS BAND UNTIL MORE WIDESPREAD LIGHT RAIN ARRIVES MONDAY
EVENING AS THE SURFACE LOW SLOWLY MOVES ACROSS THE AREA. HIGHS ON
MONDAY IN THE LOWER 50S LOOK REASONABLE AND AGAIN MADE NO CHANGES
HERE. TEMPS THEN SLOWLY FALL THROUGH THE 40S MONDAY NIGHT. CMS
&&
.LONG TERM...
TUESDAY THROUGH SATURDAY...
333 AM...AS THE SURFACE LOW MOVES ACROSS SOUTHERN LOWER MICHIGAN
TUESDAY MORNING...WINDS WILL SHIFT TO THE NORTHWEST AND BECOME
RATHER GUSTY...PERHAPS TO 30 MPH. COLDER AIR WILL SPREAD ACROSS
THE AREA. THIS WILL ALLOW LIGHT RAIN TO MIX WITH AND CHANGE TO
LIGHT SNOW FROM WEST TO EAST DURING THE MORNING INTO THE EARLY
AFTERNOON. FAIRLY LOW CONFIDENCE REGARDING TIMING BUT THE BULK OF
THE QPF SHOULD BE EXITING AS THE TRANSITION OCCURS...SO NOT
EXPECTING ANY ACCUMULATION OF SNOW.
HIGH PRESSURE WILL BUILD ACROSS THE NORTHERN PLAINS TUESDAY AND
WEDNESDAY AND THEN SPREAD INTO THE WESTERN LAKES THURSDAY. THIS
SHOULD PUSH THE THREAT OF ANY PRECIP WITH THE NEXT SYSTEM SOUTH
OF THE CWA THROUGH THURSDAY NIGHT AND LIKELY FRIDAY. BUT AS THIS
LOW LIFTS NORTHEAST ACROSS THE OHIO VALLEY...THE GFS SPREADS THE
PRECIP SHIELD AS FAR NORTH AS NORTHERN IL. IF THIS WERE TO
OCCUR...IT SHOULD BE COLD ENOUGH FOR MAINLY SNOW. BUT ECMWF...
WHICH HAS BEEN MORE CONSISTENT WITH KEEPING THIS TIME PERIOD DRY
ALSO KEEPS THIS PRECIP TO THE SOUTH. MAINTAINED LOW CHANCE POPS
FOR FRIDAY NIGHT BUT THIS WILL LIKELY SEE CHANGES WITH LATER
FORECASTS. OTHERWISE...TEMPS RETURN TO MORE TYPICAL VALUES FOR
MID DECEMBER WITH HIGHS IN THE UPPER 20S/LOWER 30S WEDNESDAY AND
THURSDAY. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* IFR CIGS AT ORD AND MVFR AT MDW. MVFR VSBY. EXPECT STEADY STATE
THIS AFTERNOON...POSSIBLY SOME IMPROVEMENT THROUGH THE EARLY
AFTERNOON.
* CIGS/VSBYS POTENTIALLY DROPPING AGAIN TONIGHT.
* SOUTHEAST WINDS TOPPING 10 KT LATER MONDAY MORNING.
KMD
//DISCUSSION...UPDATED 18Z...
MINIMAL TO VERY SLOW IMPROVEMENT HAS BEEN OCCURRING IN RECENT
HOURS...BUT CONTINUED MOIST ADVECTION INTO THE AREA HAS MAINTAINED
THE STATUS QUO WITH LIFR CEILINGS AND IFR/LIFR VSBYS ...WITH IFR
CIGS CLOSER TO CHICAGO...THEN IN THE IMMEDIATE CHICAGO
AREA...INCLUDING KMDW...DEWPOINT DEPRESSIONS REMAINED HIGHER
THROUGH THE MORNING KEEPING A POCKET OF MIXED MVFR/VFR CIGS CLOSE
TO THE LAKE...THOUGH THERE IS LIKELY SOME HAZE AND BR MIXED IN
BASED ON DOWNTOWN WEBCAMS.
DO STILL SHOW SOME GRADUAL IMPROVEMENT LATER THIS AFTERNOON AS WE
MIX A TOUCH MORE TODAY...BUT LITTLE MORE THAN IFR HAS OCCURRED
UPSTREAM UNTIL YOU GET TO THE CLEARING LINE DRAPING THE IL/MO
BORDER AND ADVANCING NORTHEAST. THEREFORE HAVE TRENDED TOWARD
KEEPING IFR IN MANY SPOTS THIS AFTERNOON WITH THE BEST CHANCE FOR
MVFR CLOSER TO CHICAGO. RUC/HRRR WHICH DO NOT HAVE A SUPERB HANDLE
ON THE CLEARING LINE DO STILL KEEP IT OUT OF THE TERMINALS
TODAY....MAYBE BRINING IT AGAIN INTO THE WESTERN TERMINALS LATE
TONIGHT AS WAS SEEN THIS MORNING AND POSSIBLY CLOSER INTO CHICAGO.
TIMING OF THIS CHALLENGING AND IF IT OCCURS WHAT IMPACTS THAT WILL
HAVE...SO FOR NOW HAVE KEPT THE SAME TRENDS.
OF CONCERN FOR TOMORROW...CIGS MAY LIFT SOME AS MIXING INCREASES
IN THE MORNING...BUT THEN HOLD AT MVFR OR WORSE FOR THE AFTERNOON AS RAIN
MOVES THROUGH. AT THIS TIME WINDS WILL BE OUT OF THE SE AND 10 KT
OR HIGHER.
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH IN IFR CIGS FOR ORD...HIGH FOR MVFR FOR MDW THOUGH LOW ON
IF IFR RETURNS THIS AFTERNOON. MEDIUM- HIGH IN HOLDING STEADY
STATE FOR THE AFTERNOON THEN DROPPING SOME TONIGHT.
* LOW IN CIG/VISBYS TONIGHT AND IF ANY CLEARING WILL OCCUR.
* MEDIUM-HIGH IN SE WINDS AT OR ABOVE 10 KT TOMORROW LATE MORNING-
AFTERNOON.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...IFR AND RAIN. SOUTH-SOUTHEAST WINDS.
TUESDAY...MVFR WITH IFR POSSIBLE. CHANCE OF RAIN IN THE MORNING
AND CHANCE OF RAIN/SNOW IN THE AFTERNOON. NORTHWEST
WINDS.
WEDNESDAY-THURSDAY...VFR LIKELY. NORTHWEST WINDS.
FRIDAY...MVFR POSSIBLE. NORTHEAST WINDS.
FRIDAY NIGHT-SATURDAY...MVFR POSSIBLE. SLGT CHANCE OF SNOW. NORTHEAST
WINDS.
MTF
&&
.MARINE...
159 AM CST
FAIRLY STAGNANT CONDITIONS OVER THE LAKE WILL CONTINUE TODAY AND
TONIGHT BEFORE APPROACHING LOW PRESSURE WILL BRING A CHANGE. IN
ADVANCE OF THIS LOW...MOISTURE WILL EASE NORTHWARD OVER THE LAKE
TODAY. THIS IS EXPECTED TO MAKE FOG BOTH MORE WIDESPREAD AND THICK
AND IT IS POSSIBLE A MARINE FOG ADVISORY WILL BE NEEDED. WINDS WILL
ALSO TURN MORE SOUTHERLY BY TONIGHT AND INCREASE IN SPEED MONDAY IN
ADVANCE OF THE LOW. STABLE CONDITIONS IMMEDIATELY ALOFT WILL KEEP
GUSTINESS TEMPERED WITH THESE SOUTHERLY WINDS. HOWEVER ONCE THE LOW
PASSES OVER THE SOUTHERN PART OF THE LAKE...THE COLD AIR ADVECTION
SHOULD DRIVE FAIRLY STOUT WINDS...WITH NORTHWEST WINDS OF 30 KT
CONTINUING TO BE LIKELY BY LATE TUESDAY MORNING THROUGH TUESDAY
NIGHT. NOT PARTICULARLY COLD AIR AT ALL FOR MID-DECEMBER WILL MOVE
IN ON THOSE WINDS...SO NOT EXPECTING ANY FREEZING SPRAY.
MTF
&&
.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:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1139 AM CST Sun Dec 14 2014
.UPDATE...
ISSUED AT 1045 AM CST SUN DEC 14 2014
16z/10am observations show visibilities gradually improving across
much of central and southeast Illinois, with dense fog now confined
to locations along/south of I-70 and from Peoria eastward to
Bloomington. Trends suggest visbys will improve enough across the
board to allow the Dense Fog Advisory to expire at 11am. Areas of
fog will likely persist into the afternoon as low-level moisture
continues to increase and surface dewpoints rise through the 40s.
Latest visible satellite imagery shows a large area of clearing
upstream across central/eastern Missouri that is slowly working
its way eastward toward the Mississippi River. Timing tools show
clearing reaching the far SW KILX CWA around Winchester by midday.
Big question will be how much further north and east the clearing
can reach, as the HRRR insists it will grind to a halt near
Jacksonville. Updated sky grids to feature partial clearing across
the far SW CWA by early afternoon, but have kept overcast
conditions in place across the remainder of the area. Made a few
minor adjustments to afternoon highs as well, with readings
ranging from the lower 50s near the Indiana border to the upper
50s west of Jacksonville where a little sunshine is likely.
&&
.SHORT TERM...(Today)
ISSUED AT 300 AM CST SUN DEC 14 2014
The deep low pressure trough currently over the Southwest will
approach Illinois today promoting enhanced southerly return flow as
the persistent high pressure ridge over the Midwest shifts eastward.
Observations and satellite imagery upstream of Illinois in this
pattern indicate pervasive cloud cover with just a few breaks
possible, but for the most part another cloudy day is in store.
Model soundings are consistent with this idea, keeping low levels
very saturated. An increase in southerly winds to around 10 mph is
on track as well. Temperatures will rise several degrees, with highs
reaching well into the 50s across central IL. Any lift remains weak
today, so precip chances are negligible, with only a little drizzle
possible in patchy of fog through noon.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 300 AM CST SUN DEC 14 2014
Deep upper trough across the Rockies starting to show signs of a
circulation in the south end across New Mexico. Evening model suite
continues to swing this upper low up into the central Plains by
Monday morning, and eastward into northern Illinois by evening. Have
made some adjustments to the timing of the rain overnight, with the
higher resolution model guidance bringing it into the western third
of the CWA after 3 am. General model consensus showing high PoP`s
Monday morning but only in about a 3-4 hour time frame at any
given location, with a relatively narrow band of showers advancing
east to near the Indiana border by midday. Would not rule out a
rumble or two of thunder with this band. Bit of a dry slot tries
to work its way in behind this line, but will have increasing
PoP`s again across the northwest during the afternoon with the
proximity of the surface low, which should be in southeast Iowa by
late afternoon. Have kept some 60% PoP`s going north of I-74 into
Monday night as the low moves northeast.
Core of the cooler air will begin moving in on Tuesday, and surface
temperatures look to move little during the day. This marks the
start of a period of temperatures near or slightly below normal,
which will persist into the weekend.
Still some challenges in the longer range in regards to the
potential late week storm system. Some broad scale agreement is
found amongst the GFS and ECMWF models through Friday, with
development of a storm system across the southern Plains as an upper
trough advances east out the Desert Southwest. A fair amount of dry
northeast flow will be persisting around a high over the northwest
Great Lakes. Forecast soundings showing only a brief period of ice
crystals aloft before being lost by the time the lower levels
finally saturate. The GFS is now largely keeping the precipitation
to our south until Friday, with the track of the surface low over
the Tennessee Valley supportive of some accumulating deformation
zone snow. The ECMWF tries to bring a bit in of precipitation on
Thursday and keeps the late week system still across the lower
Mississippi Valley, with mainly areas south of I-70 threatened on
Saturday. The forecast grids start with a blend of the two and limit
the PoP`s on Friday to the southwest CWA, becoming more widespread
Friday night and then leaning toward the ECMWF solution for
Saturday. Confidence is not very high yet, as ensembles are showing
a fair amount of spread at that range.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1139 AM CST SUN DEC 14 2014
IFR conditions will prevail through the entire 18z TAF period. Low
clouds/fog currently blanket central Illinois, although visbys are
slowly improving. Will continue to monitor a large break in the
overcast across eastern Missouri that is lifting northeastward and
may reach the SW KILX CWA early this afternoon. Latest run of the
HRRR, as well as the 12z NAM keep the clearing well southwest of
the TAF sites, so have gone with a persistence forecast of
continued IFR ceilings. Visbys will improve to between 3 and 5sm
for a period this afternoon: however, all signs are pointing to
re-development of the fog tonight. Have dropped visbys back down
to around 1sm after 00z accordingly. Next storm system is still
slated to arrive later tonight into Monday morning. Based on
NAM/GFS, have introduced rain and an improvement in visbys by 11z
at KSPI, then further east to KCMI after 14z.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Onton
LONG TERM...Geelhart
AVIATION...Barnes
AREA FORECAST DISCUSSION
NWS GOODLAND KS
246 PM MST SUN DEC 14 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 131 PM MST SUN DEC 14 2014
LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW A STRONG UPPER
LOW CENTERED OVER THE OK PANHANDLE. A DRY SLOT THAT DEVELOPED OVER
THE SOUTHERN PLAINS IS BEGINNING TO TRANSLATE NORTH AND WRAP INTO
THE UPPER LOW CENTER WITH A MOIST PLUME THAT HAS BEEN FEEDING
MODERATE TO HEAVY RAIN OVER OUR CWA. AT THE SURFACE A SLOW MOVING
COLD FRONT CURRENTLY EXTENDS FROM NORTH CENTRAL NEBRASKA TO NEAR
GOODLAND AND INTO SOUTHEAST COLORADO. BEHIND THIS FRONT
PRECIPITATION IS TRANSITIONING OVER TO SNOW.
A CONCERN WITH THIS UPDATE CYCLE WILL BE THE IMPACT OF THE DRY
SLOT ON PRECIPITATION AS THIS APPEARED TO BE MUCH MORE EXTENDING
AND ON TRACK TO OVERSPREAD THE EASTERN 2/3 OF THE FORECAST AREA.
GUIDANCE IS STILL SHOWING A DEFORMATION BAND FORMING ALONG AN
ELEVATED FRONTAL ZONE JUST NORTHWEST OF THE H7 LOW...HOWEVER THIS
MAY BE CUTOFF FROM THE BEST MOISTURE ADVECTION. RAP APPEARS TO
HAVE A SLIGHTLY BETTER HANDLE ON THIS AND SHOWS A THE SNOW BAND THIS
EVENING OVER EASTERN COLORADO BARELY PROGRESSING INTO NW KANSAS
AND OUR SW NEBRASKA COUNTIES. SNOW WILL QUICKLY TRANSITION
NORTHWARD AFTER MIDNIGHT...WITH LIGHT SNOW POSSIBLY LINGERING OVER
SW NEBRASKA INTO MONDAY AFTERNOON. RESULT OF THESE CHANGES IS
MUCH LESS SNOW ACROSS THE EASTERN 2/3 OF THE CWA THAN PREVIOUSLY
ANTICIPATED. IT DOES STILL APPEAR THAT THE HEAVIER SNOW PREVIOUSLY
ADVERTISED IN YUMA COLORADO COULD STILL MATERIALIZE...BUT OVERALL
I TRENDED OUR SNOW FORECAST BACK.
I DO NOT PLAN ON CHANGING OR REMOVING ANY HIGHLIGHTS...AS I AM
STILL CONCERNED ABOUT POSSIBLE BLOWING SNOW WITH THIS BAND AS IT
MOVES EAST AND WINDS GUST TO 45 MPH TONIGHT AND MONDAY. IF WE SEE
HEAVIER RATES (ESPECIALLY IN DUNDY...YUMA...AND POSSIBLY KIT
CARSON COUNTIES) WE COULD STILL SEE NEAR BLIZZARD OR EVEN
BLIZZARD CONDITIONS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 246 PM MST SUN DEC 14 2014
THE MAIN STORIES IN THIS EXTENDED FORECAST PERIOD ARE CHANCES FOR
LIGHT SNOW WEDNESDAY EVENING THROUGH FRIDAY AND BELOW TO NEAR NORMAL
TEMPERATURES. NO MAJOR DEVIATIONS FROM PREVIOUS FORECAST WERE MADE
AS ATTENTION WAS FOCUSED ON TODAYS SYSTEM IMPACTING THE REGION.
FOR TOMORROW NIGHT THROUGH WEDNESDAY...PRECIPITATION-FREE WEATHER IS
FORECAST AS SURFACE HIGH PRESSURE SETTLES OVER THE HIGH PLAINS.
PERIODS OF UPPER LEVEL CLOUD COVER ARE ANTICIPATED AS A WEAK UPPER
LEVEL DISTURBANCE PASSES THROUGH. TEMPERATURES WILL BE A FEW DEGREES
BELOW NORMAL DURING THIS PERIOD. SOUTH WINDS RETURN TUESDAY BEHIND
THE HIGH PRESSURE CENTER...ALLOWING SOME SLIGHTLY WARMER AIR TO MOVE
IN FOR WEDNESDAY.
AN UPPER LEVEL DISTURBANCE DIGS INTO THE SOUTHWESTERN UNITED STATES
WEDNESDAY AND EJECTS OVER THE SOUTHERN PLAINS THURSDAY INTO FRIDAY.
A LEAD SHORTWAVE MOVES THROUGH WEDNESDAY NIGHT. THIS SHORTWAVE...IN
CONJUNCTION WITH WEAK ISENTROPIC LIFT...SHOULD PROVIDE ENOUGH LIFT
FOR LIGHT PRECIPITATION TO DEVELOP. DID NOT DEVIATE FROM SUPERBLEND
POPS AS FORECAST GUIDANCE IS NOT IN STRONG AGREEMENT WITH RESPECT TO
THIS LEAD SHORTWAVE. LIGHT SNOW AMOUNTS ARE FORECAST BUT WIDESPREAD
SIGNIFICANT IMPACTS ARE ADVERTISED.
LIGHT SNOW CHANCES CONTINUE THROUGH FRIDAY AS THE MAIN DISTURBANCE
PASSES TO THE SOUTH. THERE REMAIN LARGE DIFFERENCES BETWEEN MODELS
AND THEIR PREVIOUS RUNS ON THE EVOLUTION OF THIS SYSTEM. MAINTAINED
SUPERBLEND POPS BUT CONFIDENCE IS QUITE LOW WITH REGARDS TO THIS
TIME FRAME. IF THIS SYSTEM GOES FURTHER SOUTH AS THE EUROPEAN AND
CANADIAN MODELS DISPLAY...THE REGION MAY MISS THE PRECIPITATION ALL
TOGETHER. THE GFS MODEL IS THE ONLY SOLUTION THAT CURRENTLY BRINGS
THIS DISTURBANCE FURTHER NORTH...ALLOWING PRECIPITATION DEVELOPMENT
OVER MAINLY NORTHWEST KANSAS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1032 AM MST SUN DEC 14 2014
COMPLICATED TAFS AS STRONG UPPER LOW WILL CONTINUE TO IMPACT
FLIGHT CONDITIONS OVER BOTH KGLD AND KMCK. MODERATE TO HEAVY RAIN
AND ISOLATED THUNDERSTORMS WILL IMPACT BOTH TERMINALS THIS
AFTERNOON WITH A TRANSITION TO SNOW AND BLOWING SNOW THIS EVENING.
IFR/MVFR FLIGHT CONDITIONS WILL TRANSITION TO LIFR/VLIFR THIS
EVENING AND OVERNIGHT...WITH SNOW AND BLOWING SNOW IMPACTING KGLD
FIRST (AROUND 00Z) AND KMCK LATER (AFTER 06Z). WINDS GUSTING
30-35KT ARE EXPECTED TONIGHT THROUGH MIDDAY MONDAY. WHILE
CONDITIONS WILL IMPROVE 10-13Z TIME FRAME...I AM MOST CONFIDENT
IN PREVAILING VFR AT KGLD AFTER 12Z. SNOW AND BLOWING SNOW MAY
LINGER AT KMCK THROUGH MIDDAY MONDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL 8 AM MST /9 AM CST/ MONDAY FOR
KSZ001-002-013.
CO...WINTER WEATHER ADVISORY UNTIL 8 AM MST MONDAY FOR COZ091.
WINTER STORM WARNING UNTIL 8 AM MST MONDAY FOR COZ090.
NE...WINTER WEATHER ADVISORY UNTIL 9 AM CST MONDAY FOR NEZ080-081.
WINTER STORM WARNING UNTIL 8 AM MST MONDAY FOR NEZ079.
&&
$$
SHORT TERM...DR
LONG TERM...RRH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
132 PM MST SUN DEC 14 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 131 PM MST SUN DEC 14 2014
LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW A STRONG UPPER
LOW CENTERED OVER THE OK PANHANDLE. A DRY SLOT THAT DEVELOPED OVER
THE SOUTHERN PLAINS IS BEGINNING TO TRANSLATE NORTH AND WRAP INTO
THE UPPER LOW CENTER WITH A MOIST PLUME THAT HAS BEEN FEEDING
MODERATE TO HEAVY RAIN OVER OUR CWA. AT THE SURFACE A SLOW MOVING
COLD FRONT CURRENTLY EXTENDS FROM NORTH CENTRAL NEBRASKA TO NEAR
GOODLAND AND INTO SOUTHEAST COLORADO. BEHIND THIS FRONT
PRECIPITATION IS TRANSITIONING OVER TO SNOW.
A CONCERN WITH THIS UPDATE CYCLE WILL BE THE IMPACT OF THE DRY
SLOT ON PRECIPITATION AS THIS APPEARED TO BE MUCH MORE EXTENDING
AND ON TRACK TO OVERSPREAD THE EASTERN 2/3 OF THE FORECAST AREA.
GUIDANCE IS STILL SHOWING A DEFORMATION BAND FORMING ALONG AN
ELEVATED FRONTAL ZONE JUST NORTHWEST OF THE H7 LOW...HOWEVER THIS
MAY BE CUTOFF FROM THE BEST MOISTURE ADVECTION. RAP APPEARS TO
HAVE A SLIGHTLY BETTER HANDLE ON THIS AND SHOWS A THE SNOW BAND THIS
EVENING OVER EASTERN COLORADO BARELY PROGRESSING INTO NW KANSAS
AND OUR SW NEBRASKA COUNTIES. SNOW WILL QUICKLY TRANSITION
NORTHWARD AFTER MIDNIGHT...WITH LIGHT SNOW POSSIBLY LINGERING OVER
SW NEBRASKA INTO MONDAY AFTERNOON. RESULT OF THESE CHANGES IS
MUCH LESS SNOW ACROSS THE EASTERN 2/3 OF THE CWA THAN PREVIOUSLY
ANTICIPATED. IT DOES STILL APPEAR THAT THE HEAVIER SNOW PREVIOUSLY
ADVERTISED IN YUMA COLORADO COULD STILL MATERIALIZE...BUT OVERALL
I TRENDED OUR SNOW FORECAST BACK.
I DO NOT PLAN ON CHANGING OR REMOVING ANY HIGHLIGHTS...AS I AM
STILL CONCERNED ABOUT POSSIBLE BLOWING SNOW WITH THIS BAND AS IT
MOVES EAST AND WINDS GUST TO 45 MPH TONIGHT AND MONDAY. IF WE SEE
HEAVIER RATES (ESPECIALLY IN DUNDY...YUMA...AND POSSIBLY KIT
CARSON COUNTIES) WE COULD STILL SEE NEAR BLIZZARD OR EVEN
BLIZZARD CONDITIONS.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 500 AM MST SUN DEC 14 2014
THE WEDNESDAY THROUGH FRIDAY PERIOD WILL BE NEAR NORMAL
TEMPERATURES AS THE JET STREAM REMAINS SOUTH OF THE AREA. MODELS
HAVE ALMOST DISSOLVED THE PRESENCE OF THE SHORT WAVE TROUGH ON
WEDNESDAY THAT WAS AHEAD OF THE STRONGER TROUGH DEEPENING OVER THE
WEST COAST...SO WILL NOT HAVE ANY SNOWFALL CHANCES FOR WEDNESDAY.
SNOWFALL CHANCES RETURN TO THE FORECAST WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT AS THE UPPER LEVEL LONG WAVE TROUGH OVER THE WEST
COAST MOVES EAST OVER THE DESERT SOUTHWEST TOWARD THE AREA. WITH
THE MAJORITY OF THE UPPER LEVEL DYNAMICS SOUTH OF THE
AREA...SNOWFALL AMOUNTS WILL BE UNDER 3 INCHES AT THIS TIME...WITH
THE HIGHER SNOWFALL AMOUNTS TRENDING FROM WEST TO EAST. HAVE
NOTICED OVER THE LAST COUPLE OF NIGHTS THE MODELS HAVE BEGUN NUDGING
THE LONG WAVE TROUGH NORTHWARD AS IT LIFTS NORTHEAST OVER THE
PLAINS...BRINGING THE UPPER LEVEL DYNAMICS CLOSER TO THE AREA AND
INCREASING THE POTENTIAL FOR MORE SNOWFALL. BY FRIDAY THE SNOWFALL
WILL COME TO AN END AS THE LONG WAVE TROUGH MOVES EAST OF THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1032 AM MST SUN DEC 14 2014
COMPLICATED TAFS AS STRONG UPPER LOW WILL CONTINUE TO IMPACT
FLIGHT CONDITIONS OVER BOTH KGLD AND KMCK. MODERATE TO HEAVY RAIN
AND ISOLATED THUNDERSTORMS WILL IMPACT BOTH TERMINALS THIS
AFTERNOON WITH A TRANSITION TO SNOW AND BLOWING SNOW THIS EVENING.
IFR/MVFR FLIGHT CONDITIONS WILL TRANSITION TO LIFR/VLIFR THIS
EVENING AND OVERNIGHT...WITH SNOW AND BLOWING SNOW IMPACTING KGLD
FIRST (AROUND 00Z) AND KMCK LATER (AFTER 06Z). WINDS GUSTING
30-35KT ARE EXPECTED TONIGHT THROUGH MIDDAY MONDAY. WHILE
CONDITIONS WILL IMPROVE 10-13Z TIME FRAME...I AM MOST CONFIDENT
IN PREVAILING VFR AT KGLD AFTER 12Z. SNOW AND BLOWING SNOW MAY
LINGER AT KMCK THROUGH MIDDAY MONDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL 8 AM MST /9 AM CST/ MONDAY FOR
KSZ001-002-013.
CO...WINTER WEATHER ADVISORY UNTIL 8 AM MST MONDAY FOR COZ091.
WINTER STORM WARNING UNTIL 8 AM MST MONDAY FOR COZ090.
NE...WINTER WEATHER ADVISORY UNTIL 9 AM CST MONDAY FOR NEZ080-081.
WINTER STORM WARNING UNTIL 8 AM MST MONDAY FOR NEZ079.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1033 AM MST SUN DEC 14 2014
.UPDATE...
ISSUED AT 946 AM MST SUN DEC 14 2014
MADE ADJUSTMENTS TO POP/WX/QPF/SNOW TO ACCOUNT FOR CURRENT
COVERAGE AND TIMING OF PRECIP. NEAR FREEZING TO SUB FREEZING
TEMPS WERE REPORTED ACROSS NW PARTS OF THE CWA AS MODERATE RAIN
WAS MOVING NORTH. MELTING LAYER APPEARS TO BE AROUND 3500FT BASED
ON DUAL POL FIELDS...AND RAP GENERALLY KEEPS WARM LAYER ALOFT IN
PLACE INTO THIS AFTERNOON. I WAS CONCERNED THAT AS LONG AS
SURFACE TEMPS WERE BELOW FREEZING WE COULD SEE FREEZING RAIN
ACCUMULATION...BUT SURFACES HAVE BEEN SLOWER TO RESPOND AND AIR
TEMPS ARE NOW MODERATING. I INCLUDED FREEZING RAIN MENTION THIS
MORNING AND ISSUED SPS EARLIER...HOWEVER AT THIS POINT THOUGHT IS
ANY ICING WOULD BE LOCALIZED THIS MORNING...WITH A STRAIGHT RAIN
TO SNOW TRANSITION.
IMPACT OF DRY SLOT MOVING NORTH (APPARENT ON WV IMAGERY) IS A
CONCERN. RAP SEEMS TO HAVE A DECENT HANDLE ON THIS...AND SHOWS
LESS PESSIMISTIC QPF VALUES IN OUR KS COUNTIES AND A SLOWER TIMING
ON SNOW DEVELOPMENT. I MADE SOME ADJUSTMENTS TO TIMING AND
AMOUNTS...BUT HELD OFF MAJOR OVERHAUL AS AREAS IN ADVISORY STILL
APPEAR TO SEE FAVORABLE RATES THIS EVENING OVERNIGHT. NOT
PLANNING ON CHANGING HAZARDS THIS MORNING...BUT WILL NEED TO
MONITOR.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 500 AM MST SUN DEC 14 2014
TODAY-TONIGHT...POTENT CLOSED LOW JUST STARTING TO DEVELOP OVER
NEW MEXICO AT THE BASE OF UPPER TROUGH THIS MORNING. THUNDERSTORMS
HAVE BROKEN OUT AHEAD OF THIS FEATURE AND ARE PUSHING INTO
SOUTHEAST COLORADO RIGHT NOW. BY 18Z THE LOW IS FORECAST TO REACH
SOUTHEAST COLORADO/SOUTHWEST KANSAS BORDER THEN OVER GARDEN CITY
BY DARK. AROUND MIDNIGHT THE LOW IS EXPECTED TO BE NEAR PRATT/HAYS
AREA THEN INTO THE TOPEKA AREA BY SUNRISE MONDAY MORNING.
A PLETHORA OF WEATHER POSSIBILITIES EXIST TODAY. RAIN WILL BE THE
INITIAL PRECIP TYPE WITH THUNDERSTORMS POSSIBLE AHEAD OF THE COLD
FRONT/WIND SHIFT. DURING THE LATE AFTERNOON HOURS COLDER AIR MOVES
IN WITH THE FRONT BRINGING A SMALL WINDOW OF SLEET AND MOST LIKELY
SNOW FROM WEST TO EAST. THUNDERSTORMS REMAIN POSSIBLE IN THE
NORTON AND HILL CITY AREAS TIL NEARLY MIDNIGHT.
WITH THE SNOW WILL COME NORTH TO NORTHWEST WINDS GUSTING TO 45
MPH. THIS WILL CREATE REDUCED VISIBILITIES IN SNOW AND BLOWING
SNOW. TOYED WITH A BLIZZARD WARNING FOR YUMA AND DUNDY COUNTIES
WHERE SNOWFALL WILL BE THE HEAVIEST AND GIVEN THE WINDS PRODUCE
VISIBILITIES AROUND 1/2 MILE. HAVE SETTLED ON A WINTER STORM
WARNING FOR YUMA AND DUNDY WHERE UP TO 7 INCHES OF SNOW EXPECTED
ALONG WITH VIS 1/2 MILE OR POSSIBLY LESS. THE ADVISORY AREA ISSUED
YESTERDAY WILL SEE NO CHANGES THIS SHIFT. SNOW WILL GRADUALLY
DECREASE IN COVERAGE AND INTENSITY EARLY MONDAY MORNING AND
CONTINUE TO DECREASE THROUGH THE DAY.
HIGHS TODAY IN THE 30S FOR FAR EASTERN COLORADO WITH 40S AND 50S
GENERALLY EAST OF THE STATE LINE. LOWS TONIGHT MID 20S TO LOW 30S.
MONDAY-MONDAY NIGHT...STORM SYSTEM CONTINUES NORTHEAST INTO IOWA BY
THE END OF THE DAY WITH SOME UPPER RIDGING MOVING TOWARD THE FRONT
RANGE AHEAD OF LARGE SCALE UPPER TROUGH MOVING ASHORE ACROSS THE
PACIFIC NORTHWEST BY 12Z TUESDAY. WILL HAVE QUITE A BIT OF
WRAPAROUND CLOUDINESS DURING THE MORNING WITH A DECREASE ACROSS THE
SOUTHWEST 1/2 OF THE AREA BY MID TO LATE AFTERNOON. FOR THE
OVERNIGHT HOURS CLOUDS CONTINUE TO MOVE OUT OF THE AREA THROUGH
MIDNIGHT BUT CIRRUS INCREASES ACROSS THE SOUTHWEST 1/2 OF THE AREA
TOWARD 12Z TUESDAY. HIGHS IN THE 30S TO NEAR 40 WITH LOWS IN THE
LOW TEENS TO AROUND 20.
TUESDAY-TUESDAY NIGHT...UPPER RIDGE AXIS MOVES ACROSS THE AREA LATE
IN THE DAY AND REMAINS OVER THE AREA THROUGH THE NIGHT. BATCH OF MID
AND HIGH CLOUDS STREAM ACROSS THE AREA DURING THE DAY DECREASING
FROM SOUTHWEST TO NORTHEAST BY SUNSET. FOR THE OVERNIGHT HOURS SOME
HIGH CLOUDS MOVE IN FROM THE WEST/SOUTHWEST. HIGHS IN THE UPPER
20S FOR YUMA COUNTY TO AROUND 40 IN TRIBUNE/LEOTI. LOWS IN THE MID
TEENS TO AROUND 20.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 500 AM MST SUN DEC 14 2014
THE WEDNESDAY THROUGH FRIDAY PERIOD WILL BE NEAR NORMAL
TEMPERATURES AS THE JET STREAM REMAINS SOUTH OF THE AREA. MODELS
HAVE ALMOST DISSOLVED THE PRESENCE OF THE SHORT WAVE TROUGH ON
WEDNESDAY THAT WAS AHEAD OF THE STRONGER TROUGH DEEPENING OVER THE
WEST COAST...SO WILL NOT HAVE ANY SNOWFALL CHANCES FOR WEDNESDAY.
SNOWFALL CHANCES RETURN TO THE FORECAST WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT AS THE UPPER LEVEL LONG WAVE TROUGH OVER THE WEST
COAST MOVES EAST OVER THE DESERT SOUTHWEST TOWARD THE AREA. WITH
THE MAJORITY OF THE UPPER LEVEL DYNAMICS SOUTH OF THE
AREA...SNOWFALL AMOUNTS WILL BE UNDER 3 INCHES AT THIS TIME...WITH
THE HIGHER SNOWFALL AMOUNTS TRENDING FROM WEST TO EAST. HAVE
NOTICED OVER THE LAST COUPLE OF NIGHTS THE MODELS HAVE BEGUN NUDGING
THE LONG WAVE TROUGH NORTHWARD AS IT LIFTS NORTHEAST OVER THE
PLAINS...BRINGING THE UPPER LEVEL DYNAMICS CLOSER TO THE AREA AND
INCREASING THE POTENTIAL FOR MORE SNOWFALL. BY FRIDAY THE SNOWFALL
WILL COME TO AN END AS THE LONG WAVE TROUGH MOVES EAST OF THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1032 AM MST SUN DEC 14 2014
COMPLICATED TAFS AS STRONG UPPER LOW WILL CONTINUE TO IMPACT
FLIGHT CONDITIONS OVER BOTH KGLD AND KMCK. MODERATE TO HEAVY RAIN
AND ISOLATED THUNDERSTORMS WILL IMPACT BOTH TERMINALS THIS
AFTERNOON WITH A TRANSITION TO SNOW AND BLOWING SNOW THIS EVENING.
IFR/MVFR FLIGHT CONDITIONS WILL TRANSITION TO LIFR/VLIFR THIS
EVENING AND OVERNIGHT...WITH SNOW AND BLOWING SNOW IMPACTING KGLD
FIRST (AROUND 00Z) AND KMCK LATER (AFTER 06Z). WINDS GUSTING
30-35KT ARE EXPECTED TONIGHT THROUGH MIDDAY MONDAY. WHILE
CONDITIONS WILL IMPROVE 10-13Z TIME FRAME...I AM MOST CONFIDENT
IN PREVAILING VFR AT KGLD AFTER 12Z. SNOW AND BLOWING SNOW MAY
LINGER AT KMCK THROUGH MIDDAY MONDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY FROM 2 PM MST /3 PM CST/ THIS AFTERNOON
TO 8 AM MST /9 AM CST/ MONDAY FOR KSZ001-002-013.
CO...WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO 8 AM MST
MONDAY FOR COZ091.
WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 8 AM MST MONDAY
FOR COZ090.
NE...WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 9 AM CST
MONDAY FOR NEZ080-081.
WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 8 AM MST MONDAY
FOR NEZ079.
&&
$$
UPDATE...DR
SHORT TERM...99
LONG TERM...99
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
946 AM MST SUN DEC 14 2014
.UPDATE...
ISSUED AT 946 AM MST SUN DEC 14 2014
MADE ADJUSTMENTS TO POP/WX/QPF/SNOW TO ACCOUNT FOR CURRENT
COVERAGE AND TIMING OF PRECIP. NEAR FREEZING TO SUB FREEZING
TEMPS WERE REPORTED ACROSS NW PARTS OF THE CWA AS MODERATE RAIN
WAS MOVING NORTH. MELTING LAYER APPEARS TO BE AROUND 3500FT BASED
ON DUAL POL FIELDS...AND RAP GENERALLY KEEPS WARM LAYER ALOFT IN
PLACE INTO THIS AFTERNOON. I WAS CONCERNED THAT AS LONG AS
SURFACE TEMPS WERE BELOW FREEZING WE COULD SEE FREEZING RAIN
ACCUMULATION...BUT SURFACES HAVE BEEN SLOWER TO RESPOND AND AIR
TEMPS ARE NOW MODERATING. I INCLUDED FREEZING RAIN MENTION THIS
MORNING AND ISSUED SPS EARLIER...HOWEVER AT THIS POINT THOUGHT IS
ANY ICING WOULD BE LOCALIZED THIS MORNING...WITH A STRAIGHT RAIN
TO SNOW TRANSITION.
IMPACT OF DRY SLOT MOVING NORTH (APPARENT ON WV IMAGERY) IS A
CONCERN. RAP SEEMS TO HAVE A DECENT HANDLE ON THIS...AND SHOWS
LESS PESSIMISTIC QPF VALUES IN OUR KS COUNTIES AND A SLOWER TIMING
ON SNOW DEVELOPMENT. I MADE SOME ADJUSTMENTS TO TIMING AND
AMOUNTS...BUT HELD OFF MAJOR OVERHAUL AS AREAS IN ADVISORY STILL
APPEAR TO SEE FAVORABLE RATES THIS EVENING OVERNIGHT. NOT
PLANNING ON CHANGING HAZARDS THIS MORNING...BUT WILL NEED TO
MONITOR.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 500 AM MST SUN DEC 14 2014
TODAY-TONIGHT...POTENT CLOSED LOW JUST STARTING TO DEVELOP OVER
NEW MEXICO AT THE BASE OF UPPER TROUGH THIS MORNING. THUNDERSTORMS
HAVE BROKEN OUT AHEAD OF THIS FEATURE AND ARE PUSHING INTO
SOUTHEAST COLORADO RIGHT NOW. BY 18Z THE LOW IS FORECAST TO REACH
SOUTHEAST COLORADO/SOUTHWEST KANSAS BORDER THEN OVER GARDEN CITY
BY DARK. AROUND MIDNIGHT THE LOW IS EXPECTED TO BE NEAR PRATT/HAYS
AREA THEN INTO THE TOPEKA AREA BY SUNRISE MONDAY MORNING.
A PLETHORA OF WEATHER POSSIBILITIES EXIST TODAY. RAIN WILL BE THE
INITIAL PRECIP TYPE WITH THUNDERSTORMS POSSIBLE AHEAD OF THE COLD
FRONT/WIND SHIFT. DURING THE LATE AFTERNOON HOURS COLDER AIR MOVES
IN WITH THE FRONT BRINGING A SMALL WINDOW OF SLEET AND MOST LIKELY
SNOW FROM WEST TO EAST. THUNDERSTORMS REMAIN POSSIBLE IN THE
NORTON AND HILL CITY AREAS TIL NEARLY MIDNIGHT.
WITH THE SNOW WILL COME NORTH TO NORTHWEST WINDS GUSTING TO 45
MPH. THIS WILL CREATE REDUCED VISIBILITIES IN SNOW AND BLOWING
SNOW. TOYED WITH A BLIZZARD WARNING FOR YUMA AND DUNDY COUNTIES
WHERE SNOWFALL WILL BE THE HEAVIEST AND GIVEN THE WINDS PRODUCE
VISIBILITIES AROUND 1/2 MILE. HAVE SETTLED ON A WINTER STORM
WARNING FOR YUMA AND DUNDY WHERE UP TO 7 INCHES OF SNOW EXPECTED
ALONG WITH VIS 1/2 MILE OR POSSIBLY LESS. THE ADVISORY AREA ISSUED
YESTERDAY WILL SEE NO CHANGES THIS SHIFT. SNOW WILL GRADUALLY
DECREASE IN COVERAGE AND INTENSITY EARLY MONDAY MORNING AND
CONTINUE TO DECREASE THROUGH THE DAY.
HIGHS TODAY IN THE 30S FOR FAR EASTERN COLORADO WITH 40S AND 50S
GENERALLY EAST OF THE STATE LINE. LOWS TONIGHT MID 20S TO LOW 30S.
MONDAY-MONDAY NIGHT...STORM SYSTEM CONTINUES NORTHEAST INTO IOWA BY
THE END OF THE DAY WITH SOME UPPER RIDGING MOVING TOWARD THE FRONT
RANGE AHEAD OF LARGE SCALE UPPER TROUGH MOVING ASHORE ACROSS THE
PACIFIC NORTHWEST BY 12Z TUESDAY. WILL HAVE QUITE A BIT OF
WRAPAROUND CLOUDINESS DURING THE MORNING WITH A DECREASE ACROSS THE
SOUTHWEST 1/2 OF THE AREA BY MID TO LATE AFTERNOON. FOR THE
OVERNIGHT HOURS CLOUDS CONTINUE TO MOVE OUT OF THE AREA THROUGH
MIDNIGHT BUT CIRRUS INCREASES ACROSS THE SOUTHWEST 1/2 OF THE AREA
TOWARD 12Z TUESDAY. HIGHS IN THE 30S TO NEAR 40 WITH LOWS IN THE
LOW TEENS TO AROUND 20.
TUESDAY-TUESDAY NIGHT...UPPER RIDGE AXIS MOVES ACROSS THE AREA LATE
IN THE DAY AND REMAINS OVER THE AREA THROUGH THE NIGHT. BATCH OF MID
AND HIGH CLOUDS STREAM ACROSS THE AREA DURING THE DAY DECREASING
FROM SOUTHWEST TO NORTHEAST BY SUNSET. FOR THE OVERNIGHT HOURS SOME
HIGH CLOUDS MOVE IN FROM THE WEST/SOUTHWEST. HIGHS IN THE UPPER
20S FOR YUMA COUNTY TO AROUND 40 IN TRIBUNE/LEOTI. LOWS IN THE MID
TEENS TO AROUND 20.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 500 AM MST SUN DEC 14 2014
THE WEDNESDAY THROUGH FRIDAY PERIOD WILL BE NEAR NORMAL
TEMPERATURES AS THE JET STREAM REMAINS SOUTH OF THE AREA. MODELS
HAVE ALMOST DISSOLVED THE PRESENCE OF THE SHORT WAVE TROUGH ON
WEDNESDAY THAT WAS AHEAD OF THE STRONGER TROUGH DEEPENING OVER THE
WEST COAST...SO WILL NOT HAVE ANY SNOWFALL CHANCES FOR WEDNESDAY.
SNOWFALL CHANCES RETURN TO THE FORECAST WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT AS THE UPPER LEVEL LONG WAVE TROUGH OVER THE WEST
COAST MOVES EAST OVER THE DESERT SOUTHWEST TOWARD THE AREA. WITH
THE MAJORITY OF THE UPPER LEVEL DYNAMICS SOUTH OF THE
AREA...SNOWFALL AMOUNTS WILL BE UNDER 3 INCHES AT THIS TIME...WITH
THE HIGHER SNOWFALL AMOUNTS TRENDING FROM WEST TO EAST. HAVE
NOTICED OVER THE LAST COUPLE OF NIGHTS THE MODELS HAVE BEGUN NUDGING
THE LONG WAVE TROUGH NORTHWARD AS IT LIFTS NORTHEAST OVER THE
PLAINS...BRINGING THE UPPER LEVEL DYNAMICS CLOSER TO THE AREA AND
INCREASING THE POTENTIAL FOR MORE SNOWFALL. BY FRIDAY THE SNOWFALL
WILL COME TO AN END AS THE LONG WAVE TROUGH MOVES EAST OF THE AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 500 AM MST SUN DEC 14 2014
KGLD...MVFR/IFR CONDITIONS THROUGH THE PERIOD. LIGHT FOG FROM TAF
ISSUANCE THROUGH 17Z. RAIN AND POSSIBLY SOME THUNDER FROM 18Z-20Z
WITH LIGHT SHOWERS 20Z-22Z. AFTER 22Z WINDS START TO GUST OVER
30KTS AS COLD FRONT MOVES IN. MAY SEE A SMALL WINDOW FROM 22Z-00Z
FOR RAIN...SLEET AND SNOW BEFORE CHANGING OVER TO SNOW WITH
BLOWING SNOW FROM 00Z THROUGH THE REST OF THE TAF PERIOD.
KMCK...MVFR/IFR CONDITIONS THROUGH THE PERIOD. LIGHT FOG FROM TAF
ISSUANCE THROUGH 15Z. LIGHT/MODERATE RAIN WITH THUNDER FROM 16Z
THROUGH 03Z. FROM 04Z TO 06Z A MIX OF RAIN AND SNOW AS NORTH WINDS
GUST TO 30KTS ANNOUNCING THE COLD FRONTS ARRIVAL. AFTER 06Z NORTH
WINDS GUSTING 30KTS WITH LIGHT SNOW AND BLOWING SNOW.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY FROM 2 PM MST /3 PM CST/ THIS AFTERNOON
TO 8 AM MST /9 AM CST/ MONDAY FOR KSZ001-002-013.
CO...WINTER WEATHER ADVISORY FROM 2 PM THIS AFTERNOON TO 8 AM MST
MONDAY FOR COZ091.
WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 8 AM MST MONDAY
FOR COZ090.
NE...WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 9 AM CST
MONDAY FOR NEZ080-081.
WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 8 AM MST MONDAY
FOR NEZ079.
&&
$$
UPDATE...DR
SHORT TERM...99
LONG TERM...99
AVIATION...99
AREA FORECAST DISCUSSION
NWS GAYLORD MI
600 PM EST SUN DEC 14 2014
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 412 PM EST SUN DEC 14 2014
...FOG AND STRATUS WITH STEADY TEMPS TONIGHT...
IMPACTS: DENSE FOG.
PER LATEST RAP ANALYSIS...DEEP LAYER N-S RIDGE AXIS NOW BISECTING
LAKE MICHIGAN...570 DM LINE UP ACROSS NRN LOWER MICHIGAN...WITH DEEP
CLOSED LOWS OVER THE WESTERN CONUS AND JUST OFFSHORE INTO THE
ATLANTIC. BUT OF COURSE...EXTENSIVE STRATUS AND FOG REMAINS DRAPED
ACROSS ALL THE GREAT LAKES AND MUCH OF THE MIDWEST...ALTHOUGH
THERE HAVE BEEN SOME RANDOM THINNING TO THE CLOUDS IN SPOTS AND
EVEN A FEW PEEKS OF SUN.
AS A SIDE NOTE...A RECORD 500 MB HEIGHT FOR THIS DATE OF 571 DM
WAS OBSERVED ON THIS MORNINGS 12Z APX SOUNDING...AND CLOSE TO THE
RECORD 500 MB HEIGHT FOR THE ENTIRE MONTH OF DECEMBER (5730 M).
BUT...A 850 MB TEMP OF 11.35C OBSERVED ON LAST EVENINGS APX
SOUNDING IS THE WARMEST 850 MB TEMP OBSERVED IN DECEMBER FOR NRN
MICHIGAN (PER SPC SOUNDING CLIMO STATS FROM ALL APX AND SSM UPPER
AIR SOUNDINGS GOING BACK TO 1948).
TONIGHT...STATUS QUO. STRATUS/FOG WILL ONCE AGAIN BE THE NAME OF
THE GAME. IN FACT...GUIDANCE REVEALS A BIGGER SURGE OF LOW LEVEL
MOISTURE BETWEEN 900 MB AND 800 MB (THICKER CLOUD COVER IS
EVIDENT ON SATELLITE IMAGERY ABOUT TO STREAM INTO THE REGION AND
IT IS ALSO EVIDENT ON GRB/S VAD WIND PROFILE). THIS RESULTS IN A
DEEPENING SFC BASED SATURATED LAYER AS WE GO THROUGH THE NIGHT AND
SUPPORTS THE IDEA OF WIDESPREAD DRIZZLE DEVELOPMENT. SO LITTLE OR
NO CHANGES MADE TO THE GOING FORECAST.
&&
.SHORT TERM...(MONDAY THROUGH WEDNESDAY)
ISSUED AT 412 PM EST SUN DEC 14 2014
...RAIN LOOKING LIKELY LATE MONDAY INTO TUESDAY...TURNING COOLER
MID-WEEK SOME SNOW EXPECTED...
HIGH IMPACT WEATHER POTENTIAL: LOCALLY DENSE FOG THROUGH MONDAY
MORNING. POTENTIAL FOR MOSTLY LIGHT SNOW ACCUMULATIONS TUESDAY NIGHT
INTO WEDNESDAY.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: CURRENT VERY ANOMALOUSLY
AMPLIFIED PATTERN EXPECTED TO GO THROUGH SOME CHANGES HEADING
THROUGH THE UPCOMING WEEK. DRIVER BEHIND SUCH IS A RATHER AGGRESSIVE
SPLIT FLOW PATTERN TO OUR WEST...THE LIKES OF WHICH WILL DRIVE A
PAIR OF RATHER SUBSTANTIAL SHORTWAVES THROUGH OUR AREA TO START THE
WORK WEEK. LEAD SOUTHERN STREAM ENERGY WILL BRING A ROUND OF WET
WEATHER MONDAY NIGHT INTO TUESDAY...WITH A DEEPENING NORTHERN STREAM
WAVE EXPECTED TO BRING A RETURN TO MORE TYPICAL DECEMBER WEATHER (AT
LEAST BRIEFLY) INTO MID WEEK.
PRIMARY FORECAST CHALLENGES/CONCERNS: ADDRESSING RAIN CONCERNS
THROUGH EARLY TUESDAY. TEMPERATURE TRENDS AND TRANSITION TO SNOW
THEREAFTER...ALONG WITH AT LEAST SOME POTENTIAL FOR A LITTLE
ACCUMULATION.
DETAILS: SIMPLY MORE OF THE SAME MUCH OF MONDAY WITH A SLOWLY
DEEPENING MOIST LAYER THROUGH THE DAY. DESPITE THIS...STILL APPEARS
A RATHER SUBSTANTIAL DISCONNECT WILL EXIST BETWEEN UPPER LEVEL AND
LOW LEVEL MOISTURE...SUPPORTING MORE OF A DRIZZLE/LOW CLOUD SCENARIO
THAN BONA FIDE MEASURABLE RAIN. THAT ALL CHANGES HEADING INTO MONDAY
NIGHT WITH APPROACH OF RATHER VIGOROUS SOUTHERN STREAM...WITH FORCED
ASCENT COMPLETING THE SATURATION PROCESS AS PWAT VALUES SURGE TO
NEAR THREE QUARTERS OF AN INCH. LIGHT RAIN WILL BECOME RATHER
WIDESPREAD OVERNIGHT...LASTING INTO THE START OF TUESDAY. WHILE
SOUTHERN STREAM INFLUENCES BEGIN TO DEPART LATER TUESDAY...NORTHERN
STREAM DYNAMICS BEGIN TO RAMP UP VIA STRONG SHORTWAVE DIVING INTO
THE NORTHWEST LAKES. DEEPENING COLD AIR ADVECTION EXPECTED TO FORCE
A CHANGEOVER TO SNOW FROM WEST TO EAST LATER TUESDAY...WITH ALL
AREAS COLD ENOUGH TO SUPPORT SNOW BY LATER TUESDAY EVENING. STARTING
TO LOOK LIKE MID LEVEL DRY SLOTTING WILL PUSH INTO MUCH OF NORTHERN
LOWER OVERNIGHT TUESDAY...WITH DEEPER MOISTURE TIED TO INCREASING
DEFORMATION FORCING LAYING OUT FOR AREAS IN THE STRAITS AND UPPER
MICHIGAN. LAKE SUPERIOR WILL ONLY HELP THE CAUSE AS INSTABILITY
RAMPS UP VIA STEADILY COOLING LOW LEVELS. NOT LOOKING LIKE A
PARTICULAR BIG SNOW EVENT...BUT COULD EASILY SEE A COUPLE INCHES FOR
PARTS OF EASTERN UPPER BY WEDNESDAY MORNING. LESS AMOUNTS FOR
NORTHERN LOWER...WITH SOME LIGHT ACCUMULATIONS TARGETING THE
TRADITIONAL SNOW BELTS. WNW-NW FLOW LAKE SNOWS EXPECTED TO CONTINUE
WEDNESDAY AS H8 TEMPERATURES DROP INTO THE NEGATIVE TEENS AND
NORTHERN STREAM WAVE SHEARS ACROSS THE AREA. SYNOPTIC/LAKE AUGMENTED
SURFACE TROUGHING SHOULD HELP WITH LOW LEVEL CONVERGENCE...
ESPECIALLY ACROSS EASTERN UPPER. LAKE INDUCED CLOUDS WILL BE WELL
PLACED WITHIN THE DGZ...ALTHOUGH LIMITED INVERSION LEVELS SHOULD
KEEP AMOUNTS FROM GETTING TOO OUT OF HAND. ALL TOLD...COULD SEE
ANOTHER COUPLE INCHES IN FAVORED AREAS. WILL KICK AROUND THE IDEA OF
AT LEAST INTRODUCING THIS SNOW POTENTIAL IN OUR LATEST HAZARDOUS
WEATHER PRODUCTS.
&&
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 412 PM EST SUN DEC 14 2014
BUILDING HIGH PRESSURE WILL CLEAR OUT ANY LINGERING SNOW SHOWERS BY
THURSDAY EVENING. LOW PRESSURE WILL BE PASSING SOUTH OF THE REGION
ON SATURDAY NIGHT...WITH SOME UNCERTAINTY IN THE TRACK. A MORE
NORTHERN SOLUTION COULD BRING SOME MINOR SNOWFALL WITH MOISTURE A
BIT LACKING. A SOUTHERN SOLUTION WILL LEAVE US DRY FOR ANOTHER DAY.
WILL KEEP THINGS DRY FOR NOW...KEEPING AN EYE ON THE DEVELOPMENT OF
THIS LOW PRESSURE. TEMPERATURES WILL BE NEAR NORMAL FOR THE PERIOD
WITH HIGHS IN THE UPPER 20S AND LOW 30S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 600 PM EST SUN DEC 14 2014
LOW STRATUS...FOG AND AREAS OF DRIZZLE RESULTING IN IFR
CONDITIONS WILL CONTINUE TO IMPACT ALL NRN LWR MICHIGAN TAF SITES
THRU MONDAY NIGHT AS AMPLE LOW LEVEL MOISTURE REMAINS TRAPPED
BELOW THE STRONG SUBSIDENCE INVERSION. CALM WINDS TONIGHT INTO
EARLY MONDAY WILL BECOME SOUTH BELOW 10 KTS ON MONDAY.
&&
.MARINE...
ISSUED AT 412 PM EST SUN DEC 14 2014
LIGHT WINDS THROUGH TONIGHT. A BIT STRONGER SOUTHERLY WIND WILL
DEVELOP ACROSS THE REGION MONDAY WITH SOME GUSTS GETTING UP CLOSE
TO SMALL CRAFT ADVISORY CRITERIA. BUT NO HEADLINES ARE ANTICIPATED
AT THIS POINT. WINDS TURN BACK INTO THE N/NW ON TUESDAY WITH
GUSTIER WINDS. MARINE HEADLINES MAY BE NEEDED AT THAT POINT...BUT
GALE FORCE GUSTS ARE NOT ANTICIPATED.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SHORT TERM...MSB
SHORT TERM...MSB
LONG TERM...ALM
AVIATION...MLR
MARINE...ADAM
AREA FORECAST DISCUSSION
NWS GAYLORD MI
412 PM EST SUN DEC 14 2014
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 412 PM EST SUN DEC 14 2014
...FOG AND STRATUS WITH STEADY TEMPS TONIGHT...
IMPACTS: DENSE FOG.
PER LATEST RAP ANALYSIS...DEEP LAYER N-S RIDGE AXIS NOW BISECTING
LAKE MICHIGAN...570 DM LINE UP ACROSS NRN LOWER MICHIGAN...WITH DEEP
CLOSED LOWS OVER THE WESTERN CONUS AND JUST OFFSHORE INTO THE
ATLANTIC. BUT OF COURSE...EXTENSIVE STRATUS AND FOG REMAINS DRAPED
ACROSS ALL THE GREAT LAKES AND MUCH OF THE MIDWEST...ALTHOUGH
THERE HAVE BEEN SOME RANDOM THINNING TO THE CLOUDS IN SPOTS AND
EVEN A FEW PEEKS OF SUN.
AS A SIDE NOTE...A RECORD 500 MB HEIGHT FOR THIS DATE OF 571 DM
WAS OBSERVED ON THIS MORNINGS 12Z APX SOUNDING...AND CLOSE TO THE
RECORD 500 MB HEIGHT FOR THE ENTIRE MONTH OF DECEMBER (5730 M).
BUT...A 850 MB TEMP OF 11.35C OBSERVED ON LAST EVENINGS APX
SOUNDING IS THE WARMEST 850 MB TEMP OBSERVED IN DECEMBER FOR NRN
MICHIGAN (PER SPC SOUNDING CLIMO STATS FROM ALL APX AND SSM UPPER
AIR SOUNDINGS GOING BACK TO 1948).
TONIGHT...STATUS QUO. STRATUS/FOG WILL ONCE AGAIN BE THE NAME OF
THE GAME. IN FACT...GUIDANCE REVEALS A BIGGER SURGE OF LOW LEVEL
MOISTURE BETWEEN 900 MB AND 800 MB (THICKER CLOUD COVER IS
EVIDENT ON SATELLITE IMAGERY ABOUT TO STREAM INTO THE REGION AND
IT IS ALSO EVIDENT ON GRB/S VAD WIND PROFILE). THIS RESULTS IN A
DEEPENING SFC BASED SATURATED LAYER AS WE GO THROUGH THE NIGHT AND
SUPPORTS THE IDEA OF WIDESPREAD DRIZZLE DEVELOPMENT. SO LITTLE OR
NO CHANGES MADE TO THE GOING FORECAST.
&&
.SHORT TERM...(MONDAY THROUGH WEDNESDAY)
ISSUED AT 412 PM EST SUN DEC 14 2014
...RAIN LOOKING LIKELY LATE MONDAY INTO TUESDAY...TURNING COOLER
MID-WEEK SOME SNOW EXPECTED...
HIGH IMPACT WEATHER POTENTIAL: LOCALLY DENSE FOG THROUGH MONDAY
MORNING. POTENTIAL FOR MOSTLY LIGHT SNOW ACCUMULATIONS TUESDAY NIGHT
INTO WEDNESDAY.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: CURRENT VERY ANOMALOUSLY
AMPLIFIED PATTERN EXPECTED TO GO THROUGH SOME CHANGES HEADING
THROUGH THE UPCOMING WEEK. DRIVER BEHIND SUCH IS A RATHER AGGRESSIVE
SPLIT FLOW PATTERN TO OUR WEST...THE LIKES OF WHICH WILL DRIVE A
PAIR OF RATHER SUBSTANTIAL SHORTWAVES THROUGH OUR AREA TO START THE
WORK WEEK. LEAD SOUTHERN STREAM ENERGY WILL BRING A ROUND OF WET
WEATHER MONDAY NIGHT INTO TUESDAY...WITH A DEEPENING NORTHERN STREAM
WAVE EXPECTED TO BRING A RETURN TO MORE TYPICAL DECEMBER WEATHER (AT
LEAST BRIEFLY) INTO MID WEEK.
PRIMARY FORECAST CHALLENGES/CONCERNS: ADDRESSING RAIN CONCERNS
THROUGH EARLY TUESDAY. TEMPERATURE TRENDS AND TRANSITION TO SNOW
THEREAFTER...ALONG WITH AT LEAST SOME POTENTIAL FOR A LITTLE
ACCUMULATION.
DETAILS: SIMPLY MORE OF THE SAME MUCH OF MONDAY WITH A SLOWLY
DEEPENING MOIST LAYER THROUGH THE DAY. DESPITE THIS...STILL APPEARS
A RATHER SUBSTANTIAL DISCONNECT WILL EXIST BETWEEN UPPER LEVEL AND
LOW LEVEL MOISTURE...SUPPORTING MORE OF A DRIZZLE/LOW CLOUD SCENARIO
THAN BONA FIDE MEASURABLE RAIN. THAT ALL CHANGES HEADING INTO MONDAY
NIGHT WITH APPROACH OF RATHER VIGOROUS SOUTHERN STREAM...WITH FORCED
ASCENT COMPLETING THE SATURATION PROCESS AS PWAT VALUES SURGE TO
NEAR THREE QUARTERS OF AN INCH. LIGHT RAIN WILL BECOME RATHER
WIDESPREAD OVERNIGHT...LASTING INTO THE START OF TUESDAY. WHILE
SOUTHERN STREAM INFLUENCES BEGIN TO DEPART LATER TUESDAY...NORTHERN
STREAM DYNAMICS BEGIN TO RAMP UP VIA STRONG SHORTWAVE DIVING INTO
THE NORTHWEST LAKES. DEEPENING COLD AIR ADVECTION EXPECTED TO FORCE
A CHANGEOVER TO SNOW FROM WEST TO EAST LATER TUESDAY...WITH ALL
AREAS COLD ENOUGH TO SUPPORT SNOW BY LATER TUESDAY EVENING. STARTING
TO LOOK LIKE MID LEVEL DRY SLOTTING WILL PUSH INTO MUCH OF NORTHERN
LOWER OVERNIGHT TUESDAY...WITH DEEPER MOISTURE TIED TO INCREASING
DEFORMATION FORCING LAYING OUT FOR AREAS IN THE STRAITS AND UPPER
MICHIGAN. LAKE SUPERIOR WILL ONLY HELP THE CAUSE AS INSTABILITY
RAMPS UP VIA STEADILY COOLING LOW LEVELS. NOT LOOKING LIKE A
PARTICULAR BIG SNOW EVENT...BUT COULD EASILY SEE A COUPLE INCHES FOR
PARTS OF EASTERN UPPER BY WEDNESDAY MORNING. LESS AMOUNTS FOR
NORTHERN LOWER...WITH SOME LIGHT ACCUMULATIONS TARGETING THE
TRADITIONAL SNOW BELTS. WNW-NW FLOW LAKE SNOWS EXPECTED TO CONTINUE
WEDNESDAY AS H8 TEMPERATURES DROP INTO THE NEGATIVE TEENS AND
NORTHERN STREAM WAVE SHEARS ACROSS THE AREA. SYNOPTIC/LAKE AUGMENTED
SURFACE TROUGHING SHOULD HELP WITH LOW LEVEL CONVERGENCE...
ESPECIALLY ACROSS EASTERN UPPER. LAKE INDUCED CLOUDS WILL BE WELL
PLACED WITHIN THE DGZ...ALTHOUGH LIMITED INVERSION LEVELS SHOULD
KEEP AMOUNTS FROM GETTING TOO OUT OF HAND. ALL TOLD...COULD SEE
ANOTHER COUPLE INCHES IN FAVORED AREAS. WILL KICK AROUND THE IDEA OF
AT LEAST INTRODUCING THIS SNOW POTENTIAL IN OUR LATEST HAZARDOUS
WEATHER PRODUCTS.
&&
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 412 PM EST SUN DEC 14 2014
BUILDING HIGH PRESSURE WILL CLEAR OUT ANY LINGERING SNOW SHOWERS BY
THURSDAY EVENING. LOW PRESSURE WILL BE PASSING SOUTH OF THE REGION
ON SATURDAY NIGHT...WITH SOME UNCERTAINTY IN THE TRACK. A MORE
NORTHERN SOLUTION COULD BRING SOME MINOR SNOWFALL WITH MOISTURE A
BIT LACKING. A SOUTHERN SOLUTION WILL LEAVE US DRY FOR ANOTHER DAY.
WILL KEEP THINGS DRY FOR NOW...KEEPING AN EYE ON THE DEVELOPMENT OF
THIS LOW PRESSURE. TEMPERATURES WILL BE NEAR NORMAL FOR THE PERIOD
WITH HIGHS IN THE UPPER 20S AND LOW 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1250 PM EST SUN DEC 14 2014
IFR-LIFR CONDITIONS CONTINUE TO DOMINATE NRN LOWER MICHIGAN AND
MUCH OF THE GREAT LAKES REGION TODAY...AND WILL CONTINUE TO DO SO
TONIGHT THROUGH MONDAY MIDDAY. PER SATELLITE DATA...THERE ARE A
FEW HOLES/BREAKS IN THE CLOUDS OUT THERE THAT MAY BRING SOME
TEMPORARY IMPROVEMENT TO CIGS/BRIEF MVFR CONDITIONS. BUT TIMING
THOSE RANDOM IMPROVEMENTS IS A TALL ORDER. OVERALL...ANTICIPATE
IFR CONDITIONS THROUGH MIDDAY MONDAY.
WINDS...LIGHT (5 KNOTS OR LESS) AND SOMEWHAT VARIABLE THROUGH
MONDAY...ALTHOUGH A PREVAILING LIGHT SOUTHERLY FLOW WILL BE IN
PLACE TODAY THROUGH MONDAY.
&&
.MARINE...
ISSUED AT 412 PM EST SUN DEC 14 2014
LIGHT WINDS THROUGH TONIGHT. A BIT STRONGER SOUTHERLY WIND WILL
DEVELOP ACROSS THE REGION MONDAY WITH SOME GUSTS GETTING UP CLOSE
TO SMALL CRAFT ADVISORY CRITERIA. BUT NO HEADLINES ARE ANTICIPATED
AT THIS POINT. WINDS TURN BACK INTO THE N/NW ON TUESDAY WITH
GUSTIER WINDS. MARINE HEADLINES MAY BE NEEDED AT THAT POINT...BUT
GALE FORCE GUSTS ARE NOT ANTICIPATED.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
NEAR TERM...ADAM
SHORT TERM...MSB
LONG TERM...ALM
AVIATION...ADAM
MARINE...ADAM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
323 PM EST SUN DEC 14 2014
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 323 PM EST SUN DEC 14 2014
FOG WITH AREAS OF DRIZZLE WILL CONTINUE INTO MONDAY WITH
UNSEASONABLY MILD TEMPERATURES... MOSTLY IN THE 40S.
MEANWHILE A DEVELOPING STORM SYSTEM OVER THE SOUTHERN PLAINS WILL
HEAD NORTHEAST TOWARD THE WESTERN GREAT LAKES BY MONDAY NIGHT.
THAT WILL SPREAD RAIN INTO THE AREA MONDAY NIGHT WHICH WILL
CONTINUE INTO TUESDAY AFTERNOON BEFORE THE COLD AIR COMES IN. ONCE
THE COLD AIR SURGES IN LATER IN THE DAY TUESDAY THE RAIN WILL
CHANGE TO SNOW SHOWERS AND TEMPERATURES WILL FALL INTO THE 20S.
THE SNOW SHOWERS WILL CONTINUE INTO WEDNESDAY NIGHT WITH SOME
ACCUMULATIONS NEAR AND WEST OF US-131.
A LARGE CANADIAN HIGH PRESSURE SYSTEM SHOULD INFLUENCE SOUTHWEST
MICHIGAN WEATHER THURSDAY THROUGH NEXT WEEKEND. THAT HIGH SHOULD
BLOCK THE NEXT STORM SYSTEM FROM THE WESTERN GULF FROM REACHING
MICHIGAN ON SATURDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 323 PM
EST SUN DEC 14 2014
WE HAVE SEVERAL ISSUES WITH THIS FORECAST PACKAGE. THE FIRST IS
THE FOG AND DRIZZLE TONIGHT INTO MONDAY. THEN WE HAVE THE RAIN
FROM THE SYSTEM THAT COMES THROUGH MONDAY NIGHT INTO TUESDAY.
FINALLY LAKE ENHANCED SNOW FOLLOWS FOR TUESDAY NIGHT THROUGH
WEDNESDAY.
LIKE THE PAST 2 DAYS THE FOG IS THICKEST DURING THE DAY AND THINS
OUT AFTER SUNSET. THE AREA OF DENSE FOG IS NOT NEARLY AS EXTENSIVE
TODAY AS IT WAS YESTERDAY AFTERNOON AT THIS TIME SO I DO NOT SEE ANY
ISSUE WITH HAVING TO PUT OUT A DENSE FOG ADVISORY. UNLIKE THE PAST
FEW DAYS THROUGH THE UPPER RIDGE IS NOW EAST OF SOUTHWEST MICHIGAN
WHICH MEANS THE WINDS TURN TO THE SOUTH THROUGH A DEEP LAYER. THAT
SHOULD BRING UP THE WARMER AIR JUST TO OUR SOUTH. MEANWHILE ALL OF
THE SHORT TERM... HIGH RESOLUTION... MODELS SUGGEST THE FOG AND LOW
CLOUDS WILL PERSIST INTO MONDAY. THE HRRR AND RAP13 SHOW INCREASED
LIFT IN THE LAYER BELOW THE INVERSION...SUGGESTING THE COVERAGE OF
DRIZZLE SHOULD INCREASE WITHIN THE NEXT FEW HOURS. SO I CONTINUED
THE FOG AND DRIZZLE FORECAST INTO MONDAY.
NEXT UP IS THE SYSTEM NOW DEVELOPING OVER SOUTHWEST KANSAS AND NORTHERN
TEXAS LATE THIS AFTERNOON. THIS SYSTEM IS UNDER A NEGATIVE TILT UPPER
WAVE THAT IS ALREADY CLOSED OFF AT UPPER LEVELS AND LOOKS RATHER
IMPRESSIVE ON THE WATER VAPOR LOOPS. IF IT WERE JUST THAT SYSTEM
IT WOULD DEEPEN AND TRACK WELL WEST OF MICHIGAN HOWEVER AT THE
SAME TIME WE HAVE A DIGGING NORTHERN STREAM WAVE. SO INSTEAD OF
GOING WEST OF MICHIGAN...THE NORTHERN STREAM WAVE FORCES IT TO
ROTATE AROUND A REORGANIZED UPPER LOW OVER THE GREAT LAKES TUESDAY
INTO WEDNESDAY. THE RESULT OF THAT IS THE BEST MOISTURE INFLOW
GETS CUT OFF BEFORE THE SYSTEM REACHES THIS AREA. EVEN SO WE STILL
GET SOME DEEP MOISTURE AS THE PRECIPITABLE WATER RISES FROM AROUND
A 1/2 INCH NOW TO NEARLY 3/4 OF AN INCH MONDAY EVENING. THERE IS
GOOD BUT BRIEF DEEP LIFT TUESDAY NIGHT AS THE SYSTEM MOVES INTO
THE AREA. SO I WILL RAIN MONDAY NIGHT BUT IT WILL MOSTLY BE LIGHT
RAIN...UNDER A 1/2 INCH.
FINALLY THE COLD AIR COMES IN TUESDAY AFTERNOON WHILE THE MOISTURE
IS STILL FAIRLY DEEP...SO RAIN SHOWS WILL PERSIST THROUGH THE
DAY. IT BECOMES COLD ENOUGH FOR SNOW BY MID EVENING TUESDAY SO THE
RAIN SHOWERS WILL CHANGE TO SNOW SHOWERS. THE COLDEST AIR COMES
OVERHEAD WEDNESDAY EVENING. SO WITH 850 TEMPS BELOW -10C... AND
THE LAKE NEAR 4C.... I WOULD EXPECT LAKE ENHANCED SNOWFALL INTO
WEDNESDAY. WHILE THE INVERSION HEIGHT IS LIMITED... MOSTLY UNDER
6000 FT... THERE IS LIFT AND A WEST WIND... SO THERE WILL BE SNOW
SHOWERS. TUESDAY NIGHT INTO WEDNESDAY. AT THIS POINT I AM THINKING
1 TO 3 INCHES WILL FALL FROM THIS EVENT.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 323 PM EST SUN DEC 14 2014
LAKE EFFECT SNOW SHOWERS WILL LINGER WEDNESDAY NIGHT WITH H8 TEMPS
DOWN TO AROUND -13 TO -15 C WEDNESDAY EVENING ALONG WITH DECENT
LINGERING LOW TO MID LEVEL MOISTURE. A FEW LIGHT SNOW SHOWERS AND
FLURRIES MAY LINGER INTO THURSDAY BEFORE HIGH PRESSURE BUILDS IN TO
PRODUCE FAIR WEATHER WITH SEASONABLE TEMPERATURES LATE IN THE WEEK
INTO NEXT WEEKEND.
THE TRACK OF THE GULF COAST SYSTEM LATE IN THE WEEK WILL HAVE TO BE
MONITORED AS 12Z GFS GUIDANCE SUGGESTS THAT PCPN WITH THAT SYSTEM
COULD CLIP OUR AREA ON SATURDAY. HOWEVER ALL OTHER MEDIUM RANGE
GUIDANCE HAS BEEN PERSISTENT IN SHOWING THIS SYSTEM SHOULD STAY SE
OF OUR AREA.
TEMPS THROUGH THE LONG RANGE FORECAST PERIOD WILL AVERAGE QUITE
CLOSE TO NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY)
ISSUED AT 1130 AM EST SUN DEC 14 2014
PRIMARILY IFR TO LIFR CONDITIONS ARE ANTICIPATED THIS AFTERNOON DUE
TO LOW CLOUDS AND PATCHY FOG AND DRIZZLE. IFR/LIFR CONDITIONS WILL
CONTINUE OVERNIGHT DUE TO LOW CIGS AND LOW VISBYS IN FOG AND PATCHY
DRIZZLE. CONDITIONS ARE LIKELY TO STAY MAINLY IFR THROUGH 18Z MONDAY
DUE TO LOW CIGS AND LOW VISBYS IN FOG. WINDS WILL GRADUALLY SHIFT
FROM THE SOUTHWEST THIS AFTERNOON TO THE SOUTH TONIGHT AND MONDAY
AND REMAIN AOB 10 KTS.
&&
.MARINE...
ISSUED AT 323 PM EST SUN DEC 14 2014
WINDS AND WAVES WILL STAY BELOW SMALL CRAFT ADVISORY CRITERIA
UNTIL THE COLD FRONT COMES THROUGH TUESDAY. WE WILL THEN NEED TO
ISSUE ANOTHER SMALL CRAFT ADVISORY.
&&
.HYDROLOGY...
ISSUED AT 1233 PM EST SUN DEC 14 2014
PRECIPITATION IN THE FORM OF DRIZZLE AND LIGHT RAIN WILL SPAN THE
THE PERIOD BETWEEN NOW AND TUESDAY. ANOTHER DRY PATTERN WILL SET UP
LATER IN THE WEEK. NO IMPACTS ARE EXPECTED ON AREA STREAMS AND
RIVERS THROUGH THE WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...LAURENS
AVIATION...LAURENS
HYDROLOGY...JAM
MARINE...WDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
306 PM EST SUN DEC 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EST SUN DEC 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SPLIT FLOW PATTERN ACROSS
NORTH AMERICA WITH AN UNSEASONABLY STRONG RIDGE FROM THE MS
VALLEY INTO THE WRN GREAT LAKES DOWNSTREAM FROM A TROUGH ACROSS THE
ROCKIES. AT THE SFC..SRLY WINDS WERE INCREASING FROM THE CENTRAL
PLAINS TOWARD THE UPPER MS VALLEY AHEAD OF A TROUGH FROM CENTRAL
SOUTH DAKOTA INTO WRN NEBRASKA. THE SRLY FLOW AND LOW LEVEL MOISTURE
ADVECTION HAS PUSHED DEWPOINTS TO NEAR 40F FROM CENTRAL MN AND NW WI
TO WRN UPPER MI AND INTO THE MID 30S THROUGH CNTRL UPPER MI. A
PERSISTENT LOW STRATUS DECK HAS HELPED KEEP FOG FROM BECOMING AS
DENSE OVER UPPER MI COMPARED TO LOCATIONS OVER WI.
THERE REMAINS ONLY WEAK IF ANY FORCING FOR UPWARD MOTION OVER UPPER
MI TODAY AS THE AREA REMAINS NEAR THE MID/UPPER LEVEL RIDGE AXIS.
NEVERTHELESS...THE POTENTIAL FOR DRIZZLE SPREADING ACROSS THE AREA
REMAINS AS SOME WEAK UPWARD MOTION IS EXPECTED ABOVE THE THICKENING
LOW LEVEL MOISTURE AHEAD OF THE TROUGH SLIDING INTO THE UPPER MS
VALLEY. DRIZZLE CHANCES WILL INCREASE TOWARD EVENING AS AN AREA OF
290K ISENTROPIC ASCENT IS FORECAST TO MOVE THROUGH UPPER MI...PER
NAM/GFS. IN ADDITION...MELTING SNOW WILL ADD ADDITIONAL MOISTURE TO
SUPPORT DEVELOPMENT OF AREAS OF DENSE FOG. HOWEVER...DIURNAL WARMING
SHOULD BE JUST ENOUGH TO REDUCE THE RISK FOR MORE WIDESPREAD DENSE
FOG. TONIGHT...DENSE FOG WILL BE A BETTER POSSIBILITY WITH DIURNAL
COOING AS DEWPOINTS INTO THE UPPER 30S PREVAIL ACROSS THE AREA. THE
THE POTENTIAL FOR ACCUMULATING PCPN WILL INCREASE LATE TONIGHT OVER
THE WEST WITH DEEPER MOISTURE ARRIVING AHEAD OF THE SFC TROUGH.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 305 PM EST SUN DEC 14 2014
STARTING THE LONG TERM AT 00Z TUE RESULTS IN A SHORTWAVE THAT IS
NEARLY VERTICALLY STACKED OVER A 1001MB SFC LOW IN SERN IA. A SFC
TROUGH EXTENDS NE FROM THE SFC LOW ACROSS LAKE SUPERIOR AND TOWARD
JAMES BAY...WHICH IS AHEAD OF ANOTHER SHORTWAVE OVER NWRN ONTARIO.
RAIN WILL BE ONGOING ACROSS MUCH OF THE AREA AT 00Z TUE AS 850MB AND
SFC TEMPS WILL BE ABOVE FREEZING. COLDER AIR WILL MOVE INTO THE AREA
FROM W TO E MON NIGHT INTO TUE...TRANSITIONING PRECIP TO ALL SNOW
FROM IRONWOOD TO COPPER HARBOR 03Z-09Z TUE...MARQUETTE TO IRON
MOUNTAIN 09Z-12Z...AND OVER THE ERN CWA AROUND 18Z. TRICKY FORECAST
FOR SNOWFALL AMOUNTS AS MODELS DEPICT GREATEST PRECIP OVER/NEAR WRN
LAKE SUPERIOR MON NIGHT ASSOCIATED WITH FGEN AS THE TWO SHORTWAVES
BEGIN TO INTERACT...SO FORECASTING THE EXACT LOCATION OF THE BEST
PRECIP ALONG WITH TIMING OF CHANGE OVER THE SNOW IS DIFFICULT.
THANKFULLY...MODELS ARE IN DECENT AGREEMENT WITH THE SYSTEMS. THE
SRN STREAM SHORTWAVE/SFC LOW SHIFTS E TO SRN LAKE HURON DURING THE
DAY TUE AS THE NRN SHORTWAVE MOVES INTO NRN MN. SYNOPTIC FORCING
WILL TRANSITION TO BEING PRIMARILY FROM THE NRN SHORTWAVE THROUGH
THE DAY TUE AND WITH 850MB TEMPS DROPPING TO AROUND -15C OVER WRN
LAKE SUPERIOR BY 00Z WED...LAKE ENHANCED/EFFECT SNOW WILL DEVELOP
FROM W TO E. 850MB TEMPS CONTINUE TO BE COLD THROUGH WED AS THE
SHORTWAVE MOVES JUST S OF THE CWA /ALTHOUGH THE 12Z/14 NAM SHIFT THE
SHORTWAVE ACROSS THE CWA AND THE 12Z/14 GFS IS SLOWER WITH MOVING
THE SHORTWAVE OUT OF THE REGION...THE 00Z/14 ECMWF IS ABOUT 12 HOURS
FASTER/...BUT THE AREA WILL BECOME INCREASINGLY UNDER THE INFLUENCE
OF A 1030MB OR GREATER SFC HIGH MOVING IN FROM THE NW. WITH A SFC
TROUGH HANGING BACK ACROSS LAKE SUPERIOR FROM THE EARLIER SFC
LOW...N-NW WINDS SNOWBELTS WILL BE FAVORED FOR THE LES. THINK THAT
LES WILL END BY THU MORNING IF ECMWF VERIFIES OR BE THU EVENING IF
THE GFS PANS OUT.
FOR SNOWFALL AMOUNTS...HAVE ACCUMULATIONS MON NIGHT THROUGH TUE OF
3-5 INCHES FROM IRONWOOD TO COPPER HARBOR AND OVER NERN BARAGA
COUNTY. ELSEWHERE THROUGH TUE...HAVE 0.5-1.0 INCHES NEAR LAKE
MICHIGAN AND 1-3 INCHES OVER THE NCENTRAL
/IRON...DICKINSON...MARQUETTE COUNTIES PRIMARILY/. THEN FOR
LES TUE NIGHT AND WED...HAVE AMOUNTS RANGING FROM 3-6 INCHES NEAR
LAKE SUPERIOR TO JUST A TRACE SCENTRAL. WILL CONTINUE TO DISCUSS
AMOUNTS IN THE HWO.
WITH HIGH PRESSURE IN CONTROL THROUGH AT LEAST FRI...WARMER /HIGHS
IN THE UPPER 20S TO AROUND 30/ AND DRY CONDITIONS ARE EXPECTED. FOR
THE WEEKEND...SAT SHOULD CONTINUE TO BE DRY WITH SIMILAR TEMPS TO
SAT...BUT MODELS REALLY DIVERGE ON SOLUTIONS FOR THE WEEKEND. THE
LATEST GFS CONTINUES TO SHOW A STRONG SHORTWAVE TROUGH MOVING
THROUGH THE REGION SAT NIGHT AND SUN WHILE THE ECMWF CONTINUES TO
KEEP UPPER LEVEL ENERGY SPLIT BETWEEN A STRONGER SYSTEM MOVING
ACROSS THE SRN CONUS AND A SHORTWAVE MOVING ACROSS NRN CANADA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 153 PM EST SUN DEC 14 2014
IFR TO VLIFR CEILINGS AND VIS REMAIN UNDER A STRONG INVERSION ACROSS
MUCH OF N MN/WI/AND UPPER MI. THERE ARE SOME EXCEPTIONS AS DOWNSLOPE
WINDS AT IWD HAS HELPED THEM STAY MAINLY MVFR THROUGH MUCH OF THE
DAY. IF ANY MIXING DOES OCCUR IT WILL BE PRIOR TO 22Z. AFTER THAT
ALL SITES WILL LIKELY COME IN AS VLIFR TO LIFR AS INCREASED MOISTURE
PUSHES IN FROM MN/WI...WITH IWD BEING THE SLOWEST TO RESPOND. A
BETTER CHANCE OF LIGHT RAIN/DRIZZLE WILL SLIDE INTO IWD AND CMX BY
LATE MORNING...BEFORE PUSHING E TO SAW LATE IN THE DAY AS LOW
PRESSURE MOVES ACROSS W LAKE SUPERIOR DURING THE AFTERNOON HOURS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 304 PM EST SUN DEC 14 2014
PATCHY FOG HAS BEEN REPORTED BY SEVERAL BOATS OPERATING ACROSS LAKE
SUPERIOR TODAY. THIS WILL CONTINUE TO BE THE CASE THROUGH THE DAY
MONDAY. A LOW ACROSS MINNESOTA WILL PUSH OVER W LAKE SUPERIOR MONDAY
AFTERNOON...AND THEN E LAKE SUPERIOR MONDAY EVENING /WITH FOG
DIMINISHING/. THIS WILL BE WHILE THE S END OF THE TROUGH SHIFTS FROM
KANSAS TO IOWA MONDAY...AND LOWER MICHIGAN AND THE LOWER GREAT LAKES
TUESDAY INTO TUESDAY NIGHT. EXPECT N-NW WINDS OF 20-30KTS LATE
MONDAY EVENING INTO EARLY TUESDAY EVENING. A FEW GALES TO 35KTS WILL
BE POSSIBLE.
A WEAKENING TROUGH WILL LINGER ACROSS LAKE SUPERIOR THROUGH
WEDNESDAY. LARGE HIGH PRESSURE STRETCHING FROM MANITOBA THROUGH THE
N PLAINS WILL REMAIN NEARLY STATIONARY MONDAY NIGHT THROUGH
WEDNESDAY...BEFORE SLOWLY DRIFTING ACROSS MINNESOTA AND ONTARIO
WEDNESDAY NIGHT AND THURSDAY...AND THE ENTIRE UPPER GREAT LAKES
REGION THURSDAY NIGHT INTO FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR LMZ221-248-
250.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
304 PM EST SUN DEC 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EST SUN DEC 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SPLIT FLOW PATTERN ACROSS
NORTH AMERICA WITH AN UNSEASONABLY STRONG RIDGE FROM THE MS
VALLEY INTO THE WRN GREAT LAKES DOWNSTREAM FROM A TROUGH ACROSS THE
ROCKIES. AT THE SFC..SRLY WINDS WERE INCREASING FROM THE CENTRAL
PLAINS TOWARD THE UPPER MS VALLEY AHEAD OF A TROUGH FROM CENTRAL
SOUTH DAKOTA INTO WRN NEBRASKA. THE SRLY FLOW AND LOW LEVEL MOISTURE
ADVECTION HAS PUSHED DEWPOINTS TO NEAR 40F FROM CENTRAL MN AND NW WI
TO WRN UPPER MI AND INTO THE MID 30S THROUGH CNTRL UPPER MI. A
PERSISTENT LOW STRATUS DECK HAS HELPED KEEP FOG FROM BECOMING AS
DENSE OVER UPPER MI COMPARED TO LOCATIONS OVER WI.
THERE REMAINS ONLY WEAK IF ANY FORCING FOR UPWARD MOTION OVER UPPER
MI TODAY AS THE AREA REMAINS NEAR THE MID/UPPER LEVEL RIDGE AXIS.
NEVERTHELESS...THE POTENTIAL FOR DRIZZLE SPREADING ACROSS THE AREA
REMAINS AS SOME WEAK UPWARD MOTION IS EXPECTED ABOVE THE THICKENING
LOW LEVEL MOISTURE AHEAD OF THE TROUGH SLIDING INTO THE UPPER MS
VALLEY. DRIZZLE CHANCES WILL INCREASE TOWARD EVENING AS AN AREA OF
290K ISENTROPIC ASCENT IS FORECAST TO MOVE THROUGH UPPER MI...PER
NAM/GFS. IN ADDITION...MELTING SNOW WILL ADD ADDITIONAL MOISTURE TO
SUPPORT DEVELOPMENT OF AREAS OF DENSE FOG. HOWEVER...DIURNAL WARMING
SHOULD BE JUST ENOUGH TO REDUCE THE RISK FOR MORE WIDESPREAD DENSE
FOG. TONIGHT...DENSE FOG WILL BE A BETTER POSSIBILITY WITH DIURNAL
COOING AS DEWPOINTS INTO THE UPPER 30S PREVAIL ACROSS THE AREA. THE
THE POTENTIAL FOR ACCUMULATING PCPN WILL INCREASE LATE TONIGHT OVER
THE WEST WITH DEEPER MOISTURE ARRIVING AHEAD OF THE SFC TROUGH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 257 AM EST SUN DEC 14 2014
AFTER A WARM START TO THE LONG TERM PERIOD...A RETURN TO MORE
NORMAL MID DECEMBER TEMPERATURES IS IN STORE FOR TUESDAY AND
CONTINUING THROUGH MUCH OF THE REST OF THE WORK WEEK. ON MONDAY
MORNING...THE ANOMALOUS UPPER RIDGE WILL BE LOCATED OVER THE LOWER
GREAT LAKES REGION AND QUICKLY SHIFTING EAST INTO THE NEW ENGLAND
STATES. MEANWHILE...TWO SHORTWAVES WILL BE NEARING THE AREA AND
WILL BE THE FOCUS FOR THE FIRST HALF OF THE WORK WEEK. FIRST...THE
SOUTHERN STREAM SHORTWAVE WILL BE LOCATED IN EASTERN KANSAS AT 12Z
MONDAY AND WILL BE DRIVING THE 1001MB SURFACE LOW LOCATED IN NEARLY
THE SAME LOCATION. FROM THAT SURFACE LOW...A 1006MB TROUGH WILL
EXTEND NORTHEAST THROUGH EASTERN MINNESOTA AND INTO WESTERN LAKE
SUPERIOR. AT THAT SAME TIME...A SECONDARY SHORTWAVE WILL BE DIVING
SOUTHEAST THROUGH MANITOBA. AS THE SHORTWAVE AND SURFACE LOW LIFT
NORTHEAST TOWARDS CHICAGO BY MONDAY EVENING...THE ELONGATED TROUGH
WILL SLOWLY SHIFT EAST OUT OF WESTERN LAKE SUPERIOR AND INTO THE
WESTERN U.P. AHEAD OF THE TROUGH...THE WARM/MOIST LOW LEVEL AIR
WILL CONTINUE TO PRODUCE LOW CLOUDS...DRIZZLE...AND FOG (ALTHOUGH
THERE COULD BE PERIODS OF LIGHT RAIN SHOWERS UNDER THE WEAK WARM AIR
ADVECTION AND DEEPER MOISTURE NEAR THE TROUGH AXIS). SURFACE
TEMPERATURES ON MONDAY WILL LIKELY BE FAIRLY STEADY IN THE UPPER
30S AND LOWER 40S.
HEADING INTO MONDAY NIGHT...THE SURFACE LOW AND SOUTHERN STREAM
SHORTWAVE WILL BE SLIDING INTO LOWER MICHIGAN...WHILE THE NORTHERN
STREAM SHORTWAVE BECOMES CLOSE ENOUGH TO START INTERACTING WITH
SOUTHERN SHORTWAVE. THIS WILL HELP SHIFT THE SURFACE AND LOW LEVEL
TROUGH EAST ACROSS UPPER MICHIGAN THROUGH THE NIGHT...AND BRING
COLDER LOW LEVEL AIR INTO THE AREA. OVERALL...MODELS ARE FAIRLY
CONSISTENT IN THE IDEA OF THAT COLD AIR SWITCHING THE RAIN TO SNOW
FROM NORTHWEST TO SOUTHEAST MONDAY NIGHT INTO TUESDAY MORNING.
FIRST...HAPPENING IN THE KIWD/KCMX AREA BETWEEN 02-06Z TUESDAY AND
THEN KSAW/KIMT AROUND 09Z AND AREAS OVER THE SOUTHEAST BY 18Z
TUESDAY. WITH THOSE SHORTWAVE STARTING TO INTERACT MONDAY
NIGHT...AIDING THE TIGHTENING LOW-MID LEVEL FGEN...WOULD EXPECT A
PERIOD OF MODERATE PRECIPITATION OVER WESTERN LAKE SUPERIOR AND
WESTERN UPPER MICHIGAN ON MONDAY NIGHT. SNOWFALL AMOUNTS FOR THAT
PERIOD WILL LIKELY DEPEND ON THE TIMING OF THE CHANGE OVER...BUT
WITH THE GOING TIMING WOULD EXPECT TO SEE 1-3IN FROM HERMAN TO
WATERSMEET AND WEST BY DAYBREAK TUESDAY. FARTHER EAST...THAT
DELAYED ARRIVAL OF THE COLDER AIR WILL KEEP MORE OF THE
PRECIPITATION AS RAIN BEFORE SWITCHING TO SNOW. WHEN FACTORING IN
ADDITIONAL SNOW FOR TUESDAY...MAY NEED AN ADVISORY FOR THOSE AREAS
OVER THE WEST AND WILL CONTINUE TO INCLUDE MODERATE SNOWFALL MENTION
IN THE HWO.
HEADING INTO TUESDAY...THE SURFACE LOW AND SHORTWAVE WILL SHIFT EAST
THROUGH THE LOWER GREAT LAKES AND REDUCE THE DIRECT INTERACTION OF
IT WITH THE SECONDARY SHORTWAVE NOW SLIDING SOUTH THROUGH WESTERN
LAKE SUPERIOR AND THE MINNESOTA ARROWHEAD. WHILE THIS WILL LIKELY
WEAKEN THE SYNOPTICLY FORCED PRECIPITATION...THE COLDER AIR SURGING
OVER LAKE SUPERIOR ON TUESDAY (850MB TEMPS FALLING TO AROUND -14C
OVER THE WESTERN LAKE) SHOULD LEAD TO A TRANSITION TO LAKE
ENHANCED/EFFECT SNOW OVER THE WEST INITIALLY AND THEN SHIFTING EAST
ACROSS THE REST OF THE AREA BY EVENING. CONFIDENCE DOES BEGIN TO
WAVER SOME ON TUESDAY AND CONTINUE INTO WEDNESDAY AS THE TWO
SHORTWAVE INTERACT WITH EACH OTHER OVER THE GREAT LAKES REGION.
THIS LEADS TO DIFFERENCES IN THE EXACT MODEL SOLUTIONS...BUT THE
GENERAL IDEA IS FOR THE SURFACE LOW TO CONTINUE EAST...LEAVING A
TROUGH STRETCHED WEST-NORTHWEST ACROSS LAKE SUPERIOR ON TUESDAY
AFTERNOON/EVENING UNTIL THE TRAILING SHORTWAVE CAN SLIDE IT SOUTH
WEDNESDAY. THE 00Z GFS DOES DIFFER FROM THIS IDEA AND LINGERS THE
TROUGH OVER THE UPPER GREAT LAKES UNTIL THURSDAY MORNING...WHILE THE
00Z ECMWF CAME IN A LITTLE SLOWER BUT NOT AS DELAYED AS THE GFS.
WILL FOLLOW THE GENERAL CONSENSUS AT THIS POINT AND HAVE IT MOVING
SOUTH ON TUESDAY NIGHT INTO WEDNESDAY. THEREFORE...SHOULD SEE A
PERIOD OF NORTHERLY FLOW LAKE EFFECT SPREADING ACROSS THE AREA ON
TUESDAY INTO TUESDAY NIGHT FROM WEST TO EAST AND CONTINUING INTO
WEDNESDAY. UNTIL THE COLDER AIR CAN MOVE INTO THE AREA LATER
TUESDAY AFTERNOON AND NIGHT...EXPECT THE LAKE ENHANCED PRECIPITATION
INTENSITY TO BE LIMITED TO THE WEST HALF AND WHERE IT SNOWS THE
RATIOS WILL BE ON THE LOW END (AROUND 12-1). AS THAT COLDER AIR
MOVES IN...THE CLOUD LAYER WILL NOSE INTO THE DGZ AND INCREASE THE
RATIOS...BUT THE AREA WILL ALSO START TO SEE THE AFFECT OF THE HIGH
BUILDING SOUTH INTO SOUTHERN CANADA AND THE NORTHERN PLAINS. THAT
WILL STRENGTHEN THE INVERSION AROUND 5KFT AND HELP LIMIT THE
STRENGTH OF THE LAKE EFFECT PRECIPITATION. WHILE MUCH OF THE
FORECAST DEPENDS ON THE TIMING OF THAT SURFACE TROUGH DROPPING
ACROSS THE AREA...STILL WOULD EXPECT MANY LOCATIONS IN THE NORTHERLY
WIND SNOW BELTS TO SEE A COUPLE TO SEVERAL INCHES OF LAKE
ENHANCED/EFFECT SNOW TUESDAY AFTERNOON INTO WEDNESDAY. WILL
ALSO HIGHLIGHT THIS POTENTIAL IN THE HWO AS SOME AREAS MAY SEE
ADVISORY SNOWFALL.
BEHIND THE SURFACE TROUGH...EXPECT THE LAKE EFFECT TO DIMINISH
WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING AS THE AREA OF HIGH
PRESSURE BEGINS TO SLIDE SOUTHEAST INTO THE UPPER GREAT LAKES
REGION. WARMING TEMPERATURES ALOFT WILL ARRIVE WITH UPPER RIDGE AND
LEAD TO A QUIET END TO THE WORK WEEK AND LIKELY INTO NEXT WEEKEND.
MODELS ARE FAIRLY CONSISTENT ON THE HIGH REMAINING OVER THE UPPER
GREAT LAKES REGION THROUGH THIS PERIOD. AS FOR TEMPERATURES...EXPECT
HIGHS IN THE MID-UPPER 20S FOR THE END OF THE WORK WEEK THAT MAY TRY
TO NOSE INTO THE LOWER 30S FOR NEXT WEEKEND (WHICH WOULD BE AROUND 5
DEGREES ABOVE NORMAL FOR THAT TIME OF DECEMBER).
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 153 PM EST SUN DEC 14 2014
IFR TO VLIFR CEILINGS AND VIS REMAIN UNDER A STRONG INVERSION ACROSS
MUCH OF N MN/WI/AND UPPER MI. THERE ARE SOME EXCEPTIONS AS DOWNSLOPE
WINDS AT IWD HAS HELPED THEM STAY MAINLY MVFR THROUGH MUCH OF THE
DAY. IF ANY MIXING DOES OCCUR IT WILL BE PRIOR TO 22Z. AFTER THAT
ALL SITES WILL LIKELY COME IN AS VLIFR TO LIFR AS INCREASED MOISTURE
PUSHES IN FROM MN/WI...WITH IWD BEING THE SLOWEST TO RESPOND. A
BETTER CHANCE OF LIGHT RAIN/DRIZZLE WILL SLIDE INTO IWD AND CMX BY
LATE MORNING...BEFORE PUSHING E TO SAW LATE IN THE DAY AS LOW
PRESSURE MOVES ACROSS W LAKE SUPERIOR DURING THE AFTERNOON HOURS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 304 PM EST SUN DEC 14 2014
PATCHY FOG HAS BEEN REPORTED BY SEVERAL BOATS OPERATING ACROSS LAKE
SUPERIOR TODAY. THIS WILL CONTINUE TO BE THE CASE THROUGH THE DAY
MONDAY. A LOW ACROSS MINNESOTA WILL PUSH OVER W LAKE SUPERIOR MONDAY
AFTERNOON...AND THEN E LAKE SUPERIOR MONDAY EVENING /WITH FOG
DIMINISHING/. THIS WILL BE WHILE THE S END OF THE TROUGH SHIFTS FROM
KANSAS TO IOWA MONDAY...AND LOWER MICHIGAN AND THE LOWER GREAT LAKES
TUESDAY INTO TUESDAY NIGHT. EXPECT N-NW WINDS OF 20-30KTS LATE
MONDAY EVENING INTO EARLY TUESDAY EVENING. A FEW GALES TO 35KTS WILL
BE POSSIBLE.
A WEAKENING TROUGH WILL LINGER ACROSS LAKE SUPERIOR THROUGH
WEDNESDAY. LARGE HIGH PRESSURE STRETCHING FROM MANITOBA THROUGH THE
N PLAINS WILL REMAIN NEARLY STATIONARY MONDAY NIGHT THROUGH
WEDNESDAY...BEFORE SLOWLY DRIFTING ACROSS MINNESOTA AND ONTARIO
WEDNESDAY NIGHT AND THURSDAY...AND THE ENTIRE UPPER GREAT LAKES
REGION THURSDAY NIGHT INTO FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR LMZ221-248-
250.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KF
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
154 PM EST SUN DEC 14 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EST SUN DEC 14 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A SPLIT FLOW PATTERN ACROSS
NORTH AMERICA WITH AN UNSEASONABLY STRONG RIDGE FROM THE MS
VALLEY INTO THE WRN GREAT LAKES DOWNSTREAM FROM A TROUGH ACROSS THE
ROCKIES. AT THE SFC..SRLY WINDS WERE INCREASING FROM THE CENTRAL
PLAINS TOWARD THE UPPER MS VALLEY AHEAD OF A TROUGH FROM CENTRAL
SOUTH DAKOTA INTO WRN NEBRASKA. THE SRLY FLOW AND LOW LEVEL MOISTURE
ADVECTION HAS PUSHED DEWPOINTS TO NEAR 40F FROM CENTRAL MN AND NW WI
TO WRN UPPER MI AND INTO THE MID 30S THROUGH CNTRL UPPER MI. A
PERSISTENT LOW STRATUS DECK HAS HELPED KEEP FOG FROM BECOMING AS
DENSE OVER UPPER MI COMPARED TO LOCATIONS OVER WI.
THERE REMAINS ONLY WEAK IF ANY FORCING FOR UPWARD MOTION OVER UPPER
MI TODAY AS THE AREA REMAINS NEAR THE MID/UPPER LEVEL RIDGE AXIS.
NEVERTHELESS...THE POTENTIAL FOR DRIZZLE SPREADING ACROSS THE AREA
REMAINS AS SOME WEAK UPWARD MOTION IS EXPECTED ABOVE THE THICKENING
LOW LEVEL MOISTURE AHEAD OF THE TROUGH SLIDING INTO THE UPPER MS
VALLEY. DRIZZLE CHANCES WILL INCREASE TOWARD EVENING AS AN AREA OF
290K ISENTROPIC ASCENT IS FORECAST TO MOVE THROUGH UPPER MI...PER
NAM/GFS. IN ADDITION...MELTING SNOW WILL ADD ADDITIONAL MOISTURE TO
SUPPORT DEVELOPMENT OF AREAS OF DENSE FOG. HOWEVER...DIURNAL WARMING
SHOULD BE JUST ENOUGH TO REDUCE THE RISK FOR MORE WIDESPREAD DENSE
FOG. TONIGHT...DENSE FOG WILL BE A BETTER POSSIBILITY WITH DIURNAL
COOING AS DEWPOINTS INTO THE UPPER 30S PREVAIL ACROSS THE AREA. THE
THE POTENTIAL FOR ACCUMULATING PCPN WILL INCREASE LATE TONIGHT OVER
THE WEST WITH DEEPER MOISTURE ARRIVING AHEAD OF THE SFC TROUGH.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 257 AM EST SUN DEC 14 2014
AFTER A WARM START TO THE LONG TERM PERIOD...A RETURN TO MORE
NORMAL MID DECEMBER TEMPERATURES IS IN STORE FOR TUESDAY AND
CONTINUING THROUGH MUCH OF THE REST OF THE WORK WEEK. ON MONDAY
MORNING...THE ANOMALOUS UPPER RIDGE WILL BE LOCATED OVER THE LOWER
GREAT LAKES REGION AND QUICKLY SHIFTING EAST INTO THE NEW ENGLAND
STATES. MEANWHILE...TWO SHORTWAVES WILL BE NEARING THE AREA AND
WILL BE THE FOCUS FOR THE FIRST HALF OF THE WORK WEEK. FIRST...THE
SOUTHERN STREAM SHORTWAVE WILL BE LOCATED IN EASTERN KANSAS AT 12Z
MONDAY AND WILL BE DRIVING THE 1001MB SURFACE LOW LOCATED IN NEARLY
THE SAME LOCATION. FROM THAT SURFACE LOW...A 1006MB TROUGH WILL
EXTEND NORTHEAST THROUGH EASTERN MINNESOTA AND INTO WESTERN LAKE
SUPERIOR. AT THAT SAME TIME...A SECONDARY SHORTWAVE WILL BE DIVING
SOUTHEAST THROUGH MANITOBA. AS THE SHORTWAVE AND SURFACE LOW LIFT
NORTHEAST TOWARDS CHICAGO BY MONDAY EVENING...THE ELONGATED TROUGH
WILL SLOWLY SHIFT EAST OUT OF WESTERN LAKE SUPERIOR AND INTO THE
WESTERN U.P. AHEAD OF THE TROUGH...THE WARM/MOIST LOW LEVEL AIR
WILL CONTINUE TO PRODUCE LOW CLOUDS...DRIZZLE...AND FOG (ALTHOUGH
THERE COULD BE PERIODS OF LIGHT RAIN SHOWERS UNDER THE WEAK WARM AIR
ADVECTION AND DEEPER MOISTURE NEAR THE TROUGH AXIS). SURFACE
TEMPERATURES ON MONDAY WILL LIKELY BE FAIRLY STEADY IN THE UPPER
30S AND LOWER 40S.
HEADING INTO MONDAY NIGHT...THE SURFACE LOW AND SOUTHERN STREAM
SHORTWAVE WILL BE SLIDING INTO LOWER MICHIGAN...WHILE THE NORTHERN
STREAM SHORTWAVE BECOMES CLOSE ENOUGH TO START INTERACTING WITH
SOUTHERN SHORTWAVE. THIS WILL HELP SHIFT THE SURFACE AND LOW LEVEL
TROUGH EAST ACROSS UPPER MICHIGAN THROUGH THE NIGHT...AND BRING
COLDER LOW LEVEL AIR INTO THE AREA. OVERALL...MODELS ARE FAIRLY
CONSISTENT IN THE IDEA OF THAT COLD AIR SWITCHING THE RAIN TO SNOW
FROM NORTHWEST TO SOUTHEAST MONDAY NIGHT INTO TUESDAY MORNING.
FIRST...HAPPENING IN THE KIWD/KCMX AREA BETWEEN 02-06Z TUESDAY AND
THEN KSAW/KIMT AROUND 09Z AND AREAS OVER THE SOUTHEAST BY 18Z
TUESDAY. WITH THOSE SHORTWAVE STARTING TO INTERACT MONDAY
NIGHT...AIDING THE TIGHTENING LOW-MID LEVEL FGEN...WOULD EXPECT A
PERIOD OF MODERATE PRECIPITATION OVER WESTERN LAKE SUPERIOR AND
WESTERN UPPER MICHIGAN ON MONDAY NIGHT. SNOWFALL AMOUNTS FOR THAT
PERIOD WILL LIKELY DEPEND ON THE TIMING OF THE CHANGE OVER...BUT
WITH THE GOING TIMING WOULD EXPECT TO SEE 1-3IN FROM HERMAN TO
WATERSMEET AND WEST BY DAYBREAK TUESDAY. FARTHER EAST...THAT
DELAYED ARRIVAL OF THE COLDER AIR WILL KEEP MORE OF THE
PRECIPITATION AS RAIN BEFORE SWITCHING TO SNOW. WHEN FACTORING IN
ADDITIONAL SNOW FOR TUESDAY...MAY NEED AN ADVISORY FOR THOSE AREAS
OVER THE WEST AND WILL CONTINUE TO INCLUDE MODERATE SNOWFALL MENTION
IN THE HWO.
HEADING INTO TUESDAY...THE SURFACE LOW AND SHORTWAVE WILL SHIFT EAST
THROUGH THE LOWER GREAT LAKES AND REDUCE THE DIRECT INTERACTION OF
IT WITH THE SECONDARY SHORTWAVE NOW SLIDING SOUTH THROUGH WESTERN
LAKE SUPERIOR AND THE MINNESOTA ARROWHEAD. WHILE THIS WILL LIKELY
WEAKEN THE SYNOPTICLY FORCED PRECIPITATION...THE COLDER AIR SURGING
OVER LAKE SUPERIOR ON TUESDAY (850MB TEMPS FALLING TO AROUND -14C
OVER THE WESTERN LAKE) SHOULD LEAD TO A TRANSITION TO LAKE
ENHANCED/EFFECT SNOW OVER THE WEST INITIALLY AND THEN SHIFTING EAST
ACROSS THE REST OF THE AREA BY EVENING. CONFIDENCE DOES BEGIN TO
WAVER SOME ON TUESDAY AND CONTINUE INTO WEDNESDAY AS THE TWO
SHORTWAVE INTERACT WITH EACH OTHER OVER THE GREAT LAKES REGION.
THIS LEADS TO DIFFERENCES IN THE EXACT MODEL SOLUTIONS...BUT THE
GENERAL IDEA IS FOR THE SURFACE LOW TO CONTINUE EAST...LEAVING A
TROUGH STRETCHED WEST-NORTHWEST ACROSS LAKE SUPERIOR ON TUESDAY
AFTERNOON/EVENING UNTIL THE TRAILING SHORTWAVE CAN SLIDE IT SOUTH
WEDNESDAY. THE 00Z GFS DOES DIFFER FROM THIS IDEA AND LINGERS THE
TROUGH OVER THE UPPER GREAT LAKES UNTIL THURSDAY MORNING...WHILE THE
00Z ECMWF CAME IN A LITTLE SLOWER BUT NOT AS DELAYED AS THE GFS.
WILL FOLLOW THE GENERAL CONSENSUS AT THIS POINT AND HAVE IT MOVING
SOUTH ON TUESDAY NIGHT INTO WEDNESDAY. THEREFORE...SHOULD SEE A
PERIOD OF NORTHERLY FLOW LAKE EFFECT SPREADING ACROSS THE AREA ON
TUESDAY INTO TUESDAY NIGHT FROM WEST TO EAST AND CONTINUING INTO
WEDNESDAY. UNTIL THE COLDER AIR CAN MOVE INTO THE AREA LATER
TUESDAY AFTERNOON AND NIGHT...EXPECT THE LAKE ENHANCED PRECIPITATION
INTENSITY TO BE LIMITED TO THE WEST HALF AND WHERE IT SNOWS THE
RATIOS WILL BE ON THE LOW END (AROUND 12-1). AS THAT COLDER AIR
MOVES IN...THE CLOUD LAYER WILL NOSE INTO THE DGZ AND INCREASE THE
RATIOS...BUT THE AREA WILL ALSO START TO SEE THE AFFECT OF THE HIGH
BUILDING SOUTH INTO SOUTHERN CANADA AND THE NORTHERN PLAINS. THAT
WILL STRENGTHEN THE INVERSION AROUND 5KFT AND HELP LIMIT THE
STRENGTH OF THE LAKE EFFECT PRECIPITATION. WHILE MUCH OF THE
FORECAST DEPENDS ON THE TIMING OF THAT SURFACE TROUGH DROPPING
ACROSS THE AREA...STILL WOULD EXPECT MANY LOCATIONS IN THE NORTHERLY
WIND SNOW BELTS TO SEE A COUPLE TO SEVERAL INCHES OF LAKE
ENHANCED/EFFECT SNOW TUESDAY AFTERNOON INTO WEDNESDAY. WILL
ALSO HIGHLIGHT THIS POTENTIAL IN THE HWO AS SOME AREAS MAY SEE
ADVISORY SNOWFALL.
BEHIND THE SURFACE TROUGH...EXPECT THE LAKE EFFECT TO DIMINISH
WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING AS THE AREA OF HIGH
PRESSURE BEGINS TO SLIDE SOUTHEAST INTO THE UPPER GREAT LAKES
REGION. WARMING TEMPERATURES ALOFT WILL ARRIVE WITH UPPER RIDGE AND
LEAD TO A QUIET END TO THE WORK WEEK AND LIKELY INTO NEXT WEEKEND.
MODELS ARE FAIRLY CONSISTENT ON THE HIGH REMAINING OVER THE UPPER
GREAT LAKES REGION THROUGH THIS PERIOD. AS FOR TEMPERATURES...EXPECT
HIGHS IN THE MID-UPPER 20S FOR THE END OF THE WORK WEEK THAT MAY TRY
TO NOSE INTO THE LOWER 30S FOR NEXT WEEKEND (WHICH WOULD BE AROUND 5
DEGREES ABOVE NORMAL FOR THAT TIME OF DECEMBER).
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 153 PM EST SUN DEC 14 2014
IFR TO VLIFR CEILINGS AND VIS REMAIN UNDER A STRONG INVERSION ACROSS
MUCH OF N MN/WI/AND UPPER MI. THERE ARE SOME EXCEPTIONS AS DOWNSLOPE
WINDS AT IWD HAS HELPED THEM STAY MAINLY MVFR THROUGH MUCH OF THE
DAY. IF ANY MIXING DOES OCCUR IT WILL BE PRIOR TO 22Z. AFTER THAT
ALL SITES WILL LIKELY COME IN AS VLIFR TO LIFR AS INCREASED MOISTURE
PUSHES IN FROM MN/WI...WITH IWD BEING THE SLOWEST TO RESPOND. A
BETTER CHANCE OF LIGHT RAIN/DRIZZLE WILL SLIDE INTO IWD AND CMX BY
LATE MORNING...BEFORE PUSHING E TO SAW LATE IN THE DAY AS LOW
PRESSURE MOVES ACROSS W LAKE SUPERIOR DURING THE AFTERNOON HOURS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 511 AM EST SUN DEC 14 2014
A RIDGE ACROSS THE UPPER GREAT LAKES WILL SLOWLY SHIFT TO THE LOWER
GREAT LAKES SUNDAY INTO MONDAY. LOOK FOR AN ELONGATED AREA OF LOW
PRESSURE ACROSS THE PLAINS STATES SUNDAY MORNING TO PUSH ACROSS LAKE
SUPERIOR LATE SUNDAY NIGHT INTO MONDAY...AS THE S END OF THE TROUGH
DEEPENS ACROSS IOWA ON MONDAY. THE LOW WILL PUSH ACROSS LOWER
MICHIGAN ON TUESDAY...AND EXIT ACROSS THE LOWER GREAT LAKES TUESDAY
NIGHT. A TIGHTENING GRADIENT BEHIND THE LOW PRES SYSTEM LATE MONDAY
NIGHT INTO TUESDAY IS EXPECTED TO BRING NORTH WINDS GUSTING TO 30
KNOTS WITH A FEW GALE FORCE GUSTS TO 35 KNOTS.
WINDS WILL DIMINISH FROM WED INTO WED NIGHT AS THE LOW MOVES AWAY
AND HIGH PRESSURE HIGH PRESSURE BUILDS TOWARD THE WRN LAKES FROM THE
PLAINS. WINDS WILL THEN REMAIN AT OR BELOW 20 KNOTS THU AS THE HIGH
SETTLES OVER THE REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR LMZ221-248-
250.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...KF
MARINE...JLB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1159 AM EST SUN DEC 14 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD SLOWLY EAST TODAY AND BE EAST OF THE AREA
BY THIS AFTERNOON. LOW PRESSURE WILL APPROACH FROM THE WEST AND BE
OVER LAKE ERIE BY TUESDAY EVENING. THE LOW WILL FORCE A COLD FRONT
EAST ACROSS THE AREA TUESDAY AFTERNOON AND EVENING. HIGH PRESSURE
WILL REMAIN NEARLY STATIONARY OVER MINNESOTA AND EXPAND EAST OVER
THE REGION BY FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL BE IN CONTROL OF THE LOCAL AREA THROUGH THE DAY
TODAY. HOWEVER...STRONG INVERSION WILL REMAIN PRESENT AS WARM AIR
ADVECTION TAKES PLACE MORE SO ALOFT THAN AT THE SURFACE. THIS WILL
KEEP THE LOW LEVEL MOISTURE TRAPPED UNDER THE INVERSION. LATEST
SOUNDINGS AND MODEL SOUNDINGS INDICATE DEEP LOW LEVEL MOISTURE
PRODUCING STRATUS DECK WILL REMAIN PERSISTENT THROUGH THE DAY TODAY.
DRIZZLE HAS REDEVELOPED AROUND THE CLE METRO AREA SO WILL ADD
MENTION BACK INTO THE FORECAST. HRRR SEEMS TO CONTINUE WITH PATCHY
DRIZZLE THRUT THE DAY FROM THE WEAK WARM ADVECTION LIFT SO WILL
FOLLOW SUIT IN THE FORECAST.
BUMPED UP TEMPERATURES ACROSS THE AREA...ESPECIALLY IN THE WEST
WHERE A BRIEF PEEK AT THE SUN COULD OCCUR THIS AFTERNOON AND HELP
BOOST TEMPERATURES. OTHERWISE...GENERALLY 40S FOR HIGHS TODAY AND
NEAR 50 IN THE WEST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
UPPER LEVEL RIDGE AND SURFACE HIGH PRESSURE WILL KEEP THE THREAT FOR
STRATUS DECK IN PLACE OVERNIGHT. WILL ALSO MENTION THE POTENTIAL FOR
PATCHY DRIZZLE AND PATCHY FOG DURING THE EVENING IN THE WEST AND
OVERNIGHT ELSEWHERE. SOME DRIER AIR WILL BEGIN TO PUSH INTO THE
WESTERN PORTIONS OVERNIGHT AND THIS SHOULD HELP TO LIFT SOME OF THE
STRATUS IN THAT AREA. NO GO FOR THE EASTERN TWO THIRDS OF THE AREA
THOUGH. TEMPERATURES STILL REMAIN ABOVE FREEZING AND THERE IS NO
RISK OF FREEZING PRECIPITATION.
MATTER OF FACT...IT LOOKS LIKE EVEN THOUGH WE START TO SEE SOME
DRIER AIR ON MONDAY...ELEVATED LOW LEVEL MOISTURE HOLDS STRONG TO
PREVENT ANY SUN SO WILL KEEP THE CLOUDY SKIES. NEXT SYSTEM BEGINS TO
APPROACH THE FORECAST AREA BY MONDAY EVENING AS LOW PRESSURE MOVES
NORTHEAST TO LAKE ERIE. THIS WILL FORCE A COLD FRONT ACROSS THE AREA
TUESDAY INTO TUESDAY EVENING. SHOWERS WITH THE COLD FRONT ARE
EXPECTED AS MOISTURE IN ASSOCIATION WITH THE STORM SYSTEM TRACKS
NORTHEAST INTO THE AREA.
ONCE COLD FRONT SLIDES EAST...IT WILL TAKE SOME TIME FOR THE COLDER
AIR TO ARRIVE. THIS SHOULD HOLD OFF UNTIL WEDNESDAY MORNING. LAKE
TEMPERATURE AND 850 MB TEMPERATURE DIFFERENCE IS MINIMAL BUT STILL
EXPECTING SOME LAKE EFFECT SNOW SHOWERS TO DEVELOP WITH SOME LIGHT
SNOW ACCUMULATIONS IN THE NORTHEAST WEDNESDAY INTO WEDNESDAY NIGHT.
MILD TEMPERATURES IN THE 40S FOR HIGHS EACH DAY WILL SETTLE BACK
INTO THE 30S ON WEDNESDAY. OVERNIGHT LOWS RETURN BACK TO THE 20S BY
WEDNESDAY NIGHT IN THE COLD AIR ADVECTION FLOW IN THE WAKE OF THE
LOW AND ADVANCE OF THE SURFACE HIGH PRESSURE.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
LOW PRESSURE WILL BE NEAR THE NEW ENGLAND COAST ON THURSDAY WITH
TEMPERATURES COLD ENOUGH TO PRODUCE SOME LAKE EFFECT SNOW SHOWERS
INTO THURSDAY NIGHT. HIGH PRESSURE SHOULD RIDGE INTO THE AREA FROM
CENTRAL ONTARIO KEEPING THE AREA DRY ON FRIDAY. MODELS THEN BEGIN
TO DIFFER ON THE HANDLING OF THE SOUTHERN JET STREAM LOW THAT
DEVELOPS OVER TEXAS ON FRIDAY. THE ECMWF TYPICALLY HANDLES STORM
SYSTEMS FROM THIS AREA OF THE COUNTRY BETTER THAN THE GFS. SO HAVE
LEANED TOWARD THE SLOWER ARRIVAL OF THE PRECIPITATION ON SATURDAY.
STILL WOULD NOT BE SURPRISED TO SEE THIS STORM SYSTEM EJECT
NORTHEASTWARD SLOWER THAN CURRENT THINKING.
TEMPERATURES FOR LONG TERM WE GENERALLY BE IN THE 20S FOR LOWS AND
30S FOR HIGHS.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A HOLE IN THE STRATUS DECK ACROSS NRN INDIANA MAY AFFECT KTOL AND
KFDY AT SOME POINT THROUGH THE AFTERNOON BUT OTHERWISE EXPECT
MVFR/IFR STRATUS FOG AND HAZE TO FILL BACK IN THIS EVENING AND
OVERNIGHT. ELSEWHERE EXPECT WIDESPREAD LOW MVFR AND IFR TO PERSIST
THROUGH THE PERIOD.
.OUTLOOK...NON VFR LIKELY MONDAY. AREAS OF NON VFR TUESDAY IN
RAIN SHOWERS AND ACROSS FAR NE OH/NW PA ON WEDNESDAY IN LAKE
EFFECT SNOW SHOWERS.
&&
.MARINE...
SMALL CRAFT ADVISORY WILL CONTINUE THROUGH MID MORNING. WINDS AND
WAVES SHOULD AS HIGH PRESSURE WEAKENS AND BEGINS TO SLIDE EAST. LOW
PRESSURE WILL THEN BEGIN TO MOVE INTO THE CENTRAL GREAT LAKES ON
MONDAY WITH SOUTHERLY WINDS ANTICIPATED. THE SOUTHERLY WINDS WILL
INCREASE MONDAY NIGHT BUT WILL SHIFT TO THE WEST AND NORTHWEST IN
THE WAKE OF A COLD FRONT THAT SHOULD CROSS THE LAKE TUESDAY EVENING.
WINDS WILL INCREASE WITH THE COLD ADVECTION IN THE WAKE OF THE
FRONT. AT THIS POINT IT APPEARS WINDS WILL REMAIN IN THE 15 TO 25
KNOT RANGE SO A SMALL CRAFT ADVISORY WILL BE NEED TUESDAY NIGHT INTO
AT LEAST WEDNESDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LOMBARDY
NEAR TERM...LOMBARDY
SHORT TERM...LOMBARDY
LONG TERM...MULLEN
AVIATION...TK
MARINE...MULLEN
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
337 PM CST SUN DEC 14 2014
.DISCUSSION...
WATER VAPOR...INFRARED AND VISIBLE SATELLITE IMAGERY THIS
AFTERNOON SHOW A CLASSIC UPPER LEVEL LOW OVER THE WESTERN
OKLAHOMA PANHANDLE THIS AFTERNOON. THIS SYSTEM WILL MOVE EAST
NORTHEAST ACROSS KANSAS TONIGHT. A LINE OF SHOWERS AND
THUNDERSTORMS EXTENDED ALONG A BOWIE TO BROWNWOOD LINE AT 3 PM
WHILE SCATTERED SHOWERS CONTINUED EAST OF THE MAIN LINE OF
STORMS. THE INDIVIDUAL STORMS WILL MOVE NORTHEAST AT 35 TO 40 MPH
WHILE THE LINE TREKS EAST THROUGH TONIGHT. A FEW STORMS BETWEEN
MINERAL WELLS AND BROWNWOOD HAVE INTENSIFIED SOME DURING THE LAST
HOUR. SOME STRONG TO SEVERE STORMS WILL BE POSSIBLE THROUGH THIS
EVENING...WITH DAMAGING WINDS AND MAYBE SOME MARGINAL HAIL
POSSIBLE.
THE RAIN CHANCES WILL END FROM WEST TO EAST THIS EVENING THROUGH
THE OVERNIGHT HOURS WITH JUST LOW CHANCES LINGERING IN THE
PALESTINE TO HEARNE AREAS AFTER DAYBREAK MONDAY. LOWS TONIGHT WILL
RANGE FROM THE LOWER 40S ACROSS THE WEST TO AROUND 60 DEGREES IN
THE SOUTHEAST. WITH SURFACE WINDS SHIFTING TO THE WEST TOMORROW
MORNING AND NORTHWEST TOMORROW AFTERNOON BEHIND A PACIFIC COLD FRONT
AND ABUNDANT SUNSHINE...HIGH TEMPERATURES WILL RANGE FROM AROUND
60 IN THE NORTHWEST TO AROUND 70 SOUTHEAST. THE COOLER AIR BEHIND
A COLD FRONT WILL BE MORE NOTICED MONDAY NIGHT AS WE SEE LOWS IN
THE LOWER 30S NORTHWEST TO THE LOWER 40S SOUTHEAST. HIGHS TUESDAY
WILL BE MOSTLY IN THE 50S.
AS ANOTHER UPPER LEVEL TROUGH MOVES INTO THE WEST COAST LATE
TUESDAY...WE WILL COME INTO SOUTHWESTERLY FLOW ALOFT. CLOUDS WILL
ROLL BACK INTO THE REGION FROM SOUTHWEST TO NORTHEAST TUESDAY
NIGHT WITH LOWS RANGING FROM THE MID 30S NORTHEAST TO THE LOWER
40S SOUTH. A SERIES OF UPPER LEVEL DISTURBANCES WILL MOVE ACROSS
THE REGION AHEAD OF THE UPPER LEVEL SYSTEM GIVING US CHANCES OF
SHOWERS WEDNESDAY THROUGH FRIDAY. THE MODELS ARE STILL IN
CONSIDERABLE DISAGREEMENT AMONG THE GFS...ECMWF...AND CANADIAN ON
HOW THEY HANDLE THE UPPER LEVEL TROUGH. THE GFS INDICATES THAT A
CUT OFF LOW WILL MOVE FROM SOUTHERN CALIFORNIA THURSDAY...ACROSS
THE PERMIAN BASIN BY FRIDAY MORNING...AND THEN MOVE NORTHEAST
INTO NORTHEASTERN OKLAHOMA BY FRIDAY NIGHT. THE ECMWF AND
CANADIAN INDICATE THAT A WEAKER UPPER LEVEL TROUGH WILL MOVE
ACROSS THE REGION THURSDAY NIGHT INTO FRIDAY. AT THIS TIME...HAVE
GONE WITH A BLEND OF THE MODEL SOLUTIONS.
DRY WEATHER WILL PREVAIL SATURDAY AND AS THE TROUGH MOVES FARTHER
TO THE EAST AND WE WAIT FOR THE NEXT SYSTEM TO APPROACH EARLY
NEXT WEEK.
58
&&
.AVIATION...
/ISSUED 1122 AM CST SUN DEC 14 2014/
...CONVECTION REMAINS POSSIBLE AT ALL TAF LOCATIONS THIS
AFTERNOON...
AN UPPER LEVEL LOW PRESSURE CENTER CONTINUES TO TREK ACROSS THE
TEXAS PANHANDLE...AND WILL CONTINUE ITS EASTWARD MOTION INTO THE
PLAINS THIS AFTERNOON. ASCENT ARRIVING IN ADVANCE OF THE SYSTEM
HAS LED TO THE DEVELOPMENT OF SHOWERS AND A FEW ISOLATED
THUNDERSTORMS WEST OF THE I-35 CORRIDOR THIS MORNING. THUNDERSTORM
DEVELOPMENT WILL BECOME MORE WIDESPREAD THIS AFTERNOON AS LIFT
CONTINUES TO INCREASE...AND MODEST SURFACE HEATING HELPS
DESTABILIZE THE ATMOSPHERE. AT THIS TIME...WE STILL EXPECT STORMS
TO BE SCATTERED IN NATURE IN THE METROPLEX...BUT EVENTUALLY
SOLIDIFY INTO A SQUALL LINE AS THE SYSTEM SHIFTS EAST OF TAF SITES
THIS EVENING. FOR THIS REASON WE HAVE SIMPLY MAINTAINED VCTS IN
THE TAFS...BUT WILL NEED TO AMEND WITH A TEMPO FOR AN HOUR OR SO
IF ACTIVITY BEGINS TO SHOW ORGANIZATION BEFORE MOVING EAST OF THE
METRO AREA. FOR THIS FORECAST WE HAVE LEANED TOWARDS THE RAP ON
TIMING OF THE ONSET /20Z IN THE METRO AREA AND 22Z AT KACT/ AND
CESSATION /01Z IN THE METROPLEX AND 03Z AT KACT/ OF CONVECTION.
MVFR CONDITIONS WILL LIKELY HANG AROUND AT ALL LOCATIONS MUCH OF
THE DAY. SURFACE WINDS WILL VEER THIS EVENING AS THE STORMS SYSTEM
WORKS ITS WAY EAST OF THE REGION...BRINGING IN DRIER AIR AND
IMPROVING CIGS. WINDS WILL BECOME WESTERLY OVERNIGHT AS A PACIFIC
FRONT PUSHES THROUGH THE AREA...WITH SPEEDS 10-15 KT. THERE COULD
BE SOME MINOR CROSS WIND ISSUES AT DFW TOMORROW DUE TO THE WEST
WINDS...WHICH MAY OCCASIONALLY GUST TO AROUND 20 KT MONDAY
AFTERNOON. A SECOND PUSH OF COLD AIR WILL CREATE NORTHWEST WINDS
MONDAY EVENING...OR JUST BEYOND THE EXTENDED DFW FORECAST.
30
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 50 65 39 54 38 / 40 0 0 5 5
WACO, TX 52 68 38 57 40 / 40 5 0 5 10
PARIS, TX 53 63 36 51 34 / 80 5 5 0 10
DENTON, TX 47 63 35 52 36 / 40 0 0 5 5
MCKINNEY, TX 50 63 35 52 35 / 60 5 0 5 5
DALLAS, TX 51 65 40 54 39 / 50 0 0 5 5
TERRELL, TX 53 65 38 53 37 / 70 5 0 5 5
CORSICANA, TX 56 67 39 57 40 / 60 5 0 5 5
TEMPLE, TX 54 68 38 59 42 / 30 5 0 5 10
MINERAL WELLS, TX 45 63 34 54 38 / 20 0 0 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
30/58
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1217 PM CST SUN DEC 14 2014
.UPDATE...
THERE ARE NO CHANGES TO BEING MADE TO THE MORNING FORECAST. THE
UPPER LEVEL LOW NEAR THE INTERSECTIONS OF NORTHEAST NEW MEXICO...AND
THE TEXAS AND OKLAHOMA PANHANDLES...WILL CONTINUE TO MOVE NORTHEAST
WITH SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED ACROSS NORTH AND
CENTRAL TEXAS THIS AFTERNOON AND TONIGHT. THERE REMAINS THE
POTENTIAL FOR A FEW STRONG TO SEVERE STORMS MID AFTERNOON INTO
THIS EVENING MAINLY ALONG AND EAST OF A BOWIE TO HILLSBORO LINE.
58
&&
.AVIATION...
/ISSUED 1122 AM CST SUN DEC 14 2014/
...CONVECTION REMAINS POSSIBLE AT ALL TAF LOCATIONS THIS
AFTERNOON...
AN UPPER LEVEL LOW PRESSURE CENTER CONTINUES TO TREK ACROSS THE
TEXAS PANHANDLE...AND WILL CONTINUE ITS EASTWARD MOTION INTO THE
PLAINS THIS AFTERNOON. ASCENT ARRIVING IN ADVANCE OF THE SYSTEM
HAS LED TO THE DEVELOPMENT OF SHOWERS AND A FEW ISOLATED
THUNDERSTORMS WEST OF THE I-35 CORRIDOR THIS MORNING. THUNDERSTORM
DEVELOPMENT WILL BECOME MORE WIDESPREAD THIS AFTERNOON AS LIFT
CONTINUES TO INCREASE...AND MODEST SURFACE HEATING HELPS
DESTABILIZE THE ATMOSPHERE. AT THIS TIME...WE STILL EXPECT STORMS
TO BE SCATTERED IN NATURE IN THE METROPLEX...BUT EVENTUALLY
SOLIDIFY INTO A SQUALL LINE AS THE SYSTEM SHIFTS EAST OF TAF SITES
THIS EVENING. FOR THIS REASON WE HAVE SIMPLY MAINTAINED VCTS IN
THE TAFS...BUT WILL NEED TO AMEND WITH A TEMPO FOR AN HOUR OR SO
IF ACTIVITY BEGINS TO SHOW ORGANIZATION BEFORE MOVING EAST OF THE
METRO AREA. FOR THIS FORECAST WE HAVE LEANED TOWARDS THE RAP ON
TIMING OF THE ONSET /20Z IN THE METRO AREA AND 22Z AT KACT/ AND
CESSATION /01Z IN THE METROPLEX AND 03Z AT KACT/ OF CONVECTION.
MVFR CONDITIONS WILL LIKELY HANG AROUND AT ALL LOCATIONS MUCH OF
THE DAY. SURFACE WINDS WILL VEER THIS EVENING AS THE STORMS SYSTEM
WORKS ITS WAY EAST OF THE REGION...BRINGING IN DRIER AIR AND
IMPROVING CIGS. WINDS WILL BECOME WESTERLY OVERNIGHT AS A PACIFIC
FRONT PUSHES THROUGH THE AREA...WITH SPEEDS 10-15 KT. THERE COULD
BE SOME MINOR CROSS WIND ISSUES AT DFW TOMORROW DUE TO THE WEST
WINDS...WHICH MAY OCCASIONALLY GUST TO AROUND 20 KT MONDAY
AFTERNOON. A SECOND PUSH OF COLD AIR WILL CREATE NORTHWEST WINDS
MONDAY EVENING...OR JUST BEYOND THE EXTENDED DFW FORECAST.
30
&&
.PREV DISCUSSION... /ISSUED 327 AM CST SUN DEC 14 2014/
RAIN CHANCES INCREASE ACROSS MUCH OF THE REGION TODAY AND TONIGHT
AS THE UPPER LEVEL TROUGH CONTINUES TO MOVE TOWARD THE SOUTH
PLAINS. 00Z UPPER AIR ANALYSIS HAD THE BASE OF THE TROUGH LOCATED
ROUGHLY BETWEEN SALT LAKE CITY AND PHOENIX...AND THE 08Z SATELLITE
DATA SUGGESTS THE BASE QUICKLY MOVING INTO NEW MEXICO. SYNOPTIC
SCALE AND MESOSCALE MODELS HAVE BEEN SUGGESTING THE TRANSITION TO
A CLOSED LOW OVER NEW MEXICO BY 12Z...AND THE SATELLITE DATA
CONFIRMS THAT THIS IS INDEED TAKING PLACE AS CIRCULATION CAN BE
SEEN IN THE SATELLITE DATA TO THE WEST OF KABQ. THIS FEATURE IS
EXPECTED TO MOVE NORTHEAST SOUTHERN KANSAS BY THIS EVENING.
AS THE UPPER LOW MOVES NORTHEAST...THERE WILL BE SUFFICIENT SYNOPTIC
SCALE LIFT ACROSS MUCH OF NORTH AND CENTRAL TEXAS. WITH ABUNDANT
MOISTURE IN PLACE...AND INCREASING WITH A STRONG SOUTHERLY LOW
LEVEL JET...THERE WILL BE A DECENT SHOT AT SHOWERS AND
THUNDERSTORMS TODAY. HAVE LEANED STRONGLY ON HIGH RESOLUTION
MESOSCALE MODELS...ESPECIALLY THE HRRR...FOR THE FORECAST
TODAY...INCREASING POPS FROM WEST TO EAST THROUGHOUT THE DAY. IF
ALL GOES ACCORDING TO PLAN...SHOWERS AND THUNDERSTORMS SHOULD
INCREASE IN COVERAGE BETWEEN 9 AM AND NOON TO THE WEST OF
I35/I35W. BETWEEN NOON AND 3 PM...EXPECT THE SHOWERS AND
THUNDERSTORMS TO IMPACT THE I35 CORRIDOR...INCLUDING BOTH I35W AND
I35E. THE STORMS WILL MOVE EAST FROM THERE AND PUSH EAST OF THE
AREA AFTER MIDNIGHT.
SEVERE WEATHER CHANCES TODAY ARE LOW...BUT NOT COMPLETELY OUT OF
THE QUESTION. FORECAST CAPE VALUES...AGAIN LEANING HEAVILY ON THE
HRRR...SUGGEST SOMEWHERE BETWEEN 500 AND 1000 J/KG WHICH IS NOT
TOO SHABBY FOR MID DECEMBER. LAPSE RATES SHOULD INCREASE AS THE
UPPER STORM MOVES CLOSER TO US...AND WOULD ALSO ANTICIPATE ANY CIN
TO DECREASE AS THE ENTIRE COLUMN COOLS IN RESPONSE TO SYNOPTIC
SCALE LIFT. WOULD EXPECT THAT ANY SEVERE STORM IS ISOLATED IN
COVERAGE AND WOULD BE THE EXCEPTION RATHER THAN THE RULE.
EXPECTING A PROGRESSIVE PATTERN TO CONTINUE FOR MUCH OF THE WEEK
AS TODAYS SYSTEM WILL GIVE WAY TO QUIETER WEATHER FOR MONDAY AND
TUESDAY. RAIN CHANCES INCREASE AGAIN WEDNESDAY AS THE NEXT WAVE
APPROACHES. POTENTIAL FOR RAIN CONTINUES THROUGH FRIDAY BEFORE A
RETURN TO RELATIVE QUIET FOR NEXT WEEKEND.
FOX
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 71 51 67 40 53 / 70 40 5 5 5
WACO, TX 70 51 67 40 57 / 60 50 5 5 10
PARIS, TX 66 53 63 37 51 / 70 80 10 5 5
DENTON, TX 70 47 64 36 53 / 70 30 5 5 5
MCKINNEY, TX 69 50 63 37 53 / 80 50 5 5 5
DALLAS, TX 71 51 67 41 54 / 70 40 5 5 5
TERRELL, TX 69 54 65 39 54 / 70 60 5 5 10
CORSICANA, TX 71 56 66 40 56 / 70 60 10 5 10
TEMPLE, TX 72 53 68 40 57 / 50 50 5 5 10
MINERAL WELLS, TX 71 43 64 35 55 / 40 10 5 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
30/58
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1122 AM CST SUN DEC 14 2014
.AVIATION...
...CONVECTION REMAINS POSSIBLE AT ALL TAF LOCATIONS THIS
AFTERNOON...
AN UPPER LEVEL LOW PRESSURE CENTER CONTINUES TO TREK ACROSS THE
TEXAS PANHANDLE...AND WILL CONTINUE ITS EASTWARD MOTION INTO THE
PLAINS THIS AFTERNOON. ASCENT ARRIVING IN ADVANCE OF THE SYSTEM
HAS LED TO THE DEVELOPMENT OF SHOWERS AND A FEW ISOLATED
THUNDERSTORMS WEST OF THE I-35 CORRIDOR THIS MORNING. THUNDERSTORM
DEVELOPMENT WILL BECOME MORE WIDESPREAD THIS AFTERNOON AS LIFT
CONTINUES TO INCREASE...AND MODEST SURFACE HEATING HELPS
DESTABILIZE THE ATMOSPHERE. AT THIS TIME...WE STILL EXPECT STORMS
TO BE SCATTERED IN NATURE IN THE METROPLEX...BUT EVENTUALLY
SOLIDIFY INTO A SQUALL LINE AS THE SYSTEM SHIFTS EAST OF TAF SITES
THIS EVENING. FOR THIS REASON WE HAVE SIMPLY MAINTAINED VCTS IN
THE TAFS...BUT WILL NEED TO AMEND WITH A TEMPO FOR AN HOUR OR SO
IF ACTIVITY BEGINS TO SHOW ORGANIZATION BEFORE MOVING EAST OF THE
METRO AREA. FOR THIS FORECAST WE HAVE LEANED TOWARDS THE RAP ON
TIMING OF THE ONSET /20Z IN THE METRO AREA AND 22Z AT KACT/ AND
CESSATION /01Z IN THE METROPLEX AND 03Z AT KACT/ OF CONVECTION.
MVFR CONDITIONS WILL LIKELY HANG AROUND AT ALL LOCATIONS MUCH OF
THE DAY. SURFACE WINDS WILL VEER THIS EVENING AS THE STORMS SYSTEM
WORKS ITS WAY EAST OF THE REGION...BRINGING IN DRIER AIR AND
IMPROVING CIGS. WINDS WILL BECOME WESTERLY OVERNIGHT AS A PACIFIC
FRONT PUSHES THROUGH THE AREA...WITH SPEEDS 10-15 KT. THERE COULD
BE SOME MINOR CROSS WIND ISSUES AT DFW TOMORROW DUE TO THE WEST
WINDS...WHICH MAY OCCASIONALLY GUST TO AROUND 20 KT MONDAY
AFTERNOON. A SECOND PUSH OF COLD AIR WILL CREATE NORTHWEST WINDS
MONDAY EVENING...OR JUST BEYOND THE EXTENDED DFW FORECAST.
30
&&
.PREV DISCUSSION... /ISSUED 327 AM CST SUN DEC 14 2014/
RAIN CHANCES INCREASE ACROSS MUCH OF THE REGION TODAY AND TONIGHT
AS THE UPPER LEVEL TROUGH CONTINUES TO MOVE TOWARD THE SOUTH
PLAINS. 00Z UPPER AIR ANALYSIS HAD THE BASE OF THE TROUGH LOCATED
ROUGHLY BETWEEN SALT LAKE CITY AND PHOENIX...AND THE 08Z SATELLITE
DATA SUGGESTS THE BASE QUICKLY MOVING INTO NEW MEXICO. SYNOPTIC
SCALE AND MESOSCALE MODELS HAVE BEEN SUGGESTING THE TRANSITION TO
A CLOSED LOW OVER NEW MEXICO BY 12Z...AND THE SATELLITE DATA
CONFIRMS THAT THIS IS INDEED TAKING PLACE AS CIRCULATION CAN BE
SEEN IN THE SATELLITE DATA TO THE WEST OF KABQ. THIS FEATURE IS
EXPECTED TO MOVE NORTHEAST SOUTHERN KANSAS BY THIS EVENING.
AS THE UPPER LOW MOVES NORTHEAST...THERE WILL BE SUFFICIENT SYNOPTIC
SCALE LIFT ACROSS MUCH OF NORTH AND CENTRAL TEXAS. WITH ABUNDANT
MOISTURE IN PLACE...AND INCREASING WITH A STRONG SOUTHERLY LOW
LEVEL JET...THERE WILL BE A DECENT SHOT AT SHOWERS AND
THUNDERSTORMS TODAY. HAVE LEANED STRONGLY ON HIGH RESOLUTION
MESOSCALE MODELS...ESPECIALLY THE HRRR...FOR THE FORECAST
TODAY...INCREASING POPS FROM WEST TO EAST THROUGHOUT THE DAY. IF
ALL GOES ACCORDING TO PLAN...SHOWERS AND THUNDERSTORMS SHOULD
INCREASE IN COVERAGE BETWEEN 9 AM AND NOON TO THE WEST OF
I35/I35W. BETWEEN NOON AND 3 PM...EXPECT THE SHOWERS AND
THUNDERSTORMS TO IMPACT THE I35 CORRIDOR...INCLUDING BOTH I35W AND
I35E. THE STORMS WILL MOVE EAST FROM THERE AND PUSH EAST OF THE
AREA AFTER MIDNIGHT.
SEVERE WEATHER CHANCES TODAY ARE LOW...BUT NOT COMPLETELY OUT OF
THE QUESTION. FORECAST CAPE VALUES...AGAIN LEANING HEAVILY ON THE
HRRR...SUGGEST SOMEWHERE BETWEEN 500 AND 1000 J/KG WHICH IS NOT
TOO SHABBY FOR MID DECEMBER. LAPSE RATES SHOULD INCREASE AS THE
UPPER STORM MOVES CLOSER TO US...AND WOULD ALSO ANTICIPATE ANY CIN
TO DECREASE AS THE ENTIRE COLUMN COOLS IN RESPONSE TO SYNOPTIC
SCALE LIFT. WOULD EXPECT THAT ANY SEVERE STORM IS ISOLATED IN
COVERAGE AND WOULD BE THE EXCEPTION RATHER THAN THE RULE.
EXPECTING A PROGRESSIVE PATTERN TO CONTINUE FOR MUCH OF THE WEEK
AS TODAYS SYSTEM WILL GIVE WAY TO QUIETER WEATHER FOR MONDAY AND
TUESDAY. RAIN CHANCES INCREASE AGAIN WEDNESDAY AS THE NEXT WAVE
APPROACHES. POTENTIAL FOR RAIN CONTINUES THROUGH FRIDAY BEFORE A
RETURN TO RELATIVE QUIET FOR NEXT WEEKEND.
FOX
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 71 51 67 40 53 / 70 40 5 5 5
WACO, TX 70 51 67 40 57 / 60 50 5 5 10
PARIS, TX 66 53 63 37 51 / 70 80 10 5 5
DENTON, TX 70 47 64 36 53 / 70 30 5 5 5
MCKINNEY, TX 69 50 63 37 53 / 80 50 5 5 5
DALLAS, TX 71 51 67 41 54 / 70 40 5 5 5
TERRELL, TX 69 54 65 39 54 / 70 60 5 5 10
CORSICANA, TX 71 56 66 40 56 / 70 60 10 5 10
TEMPLE, TX 72 53 68 40 57 / 50 50 5 5 10
MINERAL WELLS, TX 71 43 64 35 55 / 40 10 5 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
30/58
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1119 AM CST SUN DEC 14 2014
.DISCUSSION...
SEE 18Z AVIATION DISCUSSION.
&&
.AVIATION...
MODELS NOT IN THE BEST AGREEMENT ONCE AGAIN WITH REGARD TO RAIN
CHANCES AND MVFR/IFR CIGS. LATEST RAP AND 4 KM WRF KEEPS MOST OF
THE RAINFALL TO THE NW OF THE AREA WITH ONLY WIDELY SCATTERED
SHOWERS OVER AREA TAF SITES. FCST SOUNDINGS SHOW ONLY A SMALL
SATURATED PROFILE WITH CONSIDERABLE DRY AIR ALOFT. PARED BACK RAIN
CHANCES FOR THIS AFTN AS COVERAGE SHOULD REMAIN SPOTTY. WILL
BRIEFLY CARRY LIFR CIGS OVERNIGHT BUT NOT MUCH CONFIDENCE IN THIS
ACTUALLY OCCURRING. WINDS WILL BE GUSTY THIS AFTN AND TRENDED
HIGHER WITH BOTH SUSTAINED WINDS AND GUSTS. 43
&&
.PREV DISCUSSION... /ISSUED 1013 AM CST SUN DEC 14 2014/
UPDATE...
NO SIGNIFICANT CHANGES TO THE SHORT TERM GRIDS. AFTERNOON LOW END
RAIN CHANCES FOR PRIMARILY SHOWERS UP ACROSS THE NORTHERN THIRD
OF THE CWA WILL HEIGHTEN TO HIGH CHANCE/LIKELY FOR SHOWERS WITH
ISOLATED STORMS THROUGH EARLY MONDAY MORNING. THE IMPETUS WILL BE
THE DEVELOPING ROCKY MOUNTAIN LEESIDE LOW OVER SE CO AND OK/TX
PANHANDLES THAT WILL EJECT NORTHEAST THROUGH EARLY MONDAY...ITS
ASSOCIATED COLD FRONT TO PASS OVER THE REGION LATE MONDAY. UPPER
LEVEL SUPPORT IS NOT THERE...WITH CONTINUED DRY MID-UPPER LAYERS
WITHIN A MARGINALLY UNSTABLE PROFILE...TO PRODUCE NO MORE THAN
JUST SCATTERED SHOWERS FOR THE MAJORITY OF THE FORECAST AREA OVER
THE NEXT 24 TO 36 HOURS. DOWNSTREAM OF THIS FRONT...THE WARMEST
DAYS OF THE WEEK WITH MAXIMUM TEMPERATURES REGISTERING A NEAR 10
DEGREES ABOVE NORMAL PER MID DECEMBER STANDARDS. THE POST FRONTAL
AIR MASS WILL BE RELATIVELY COOLER...BUT MILD CONDITIONS WILL
STILL PERSIST THROUGH THIS LAST FULL WEEK OF AUTUMN AS CLOUDINESS
AND PERIODIC RAINFALL REGULATE DIURNAL TEMPERATURE FLUCTUATION. 31
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 74 62 73 44 61 / 30 50 20 10 10
HOUSTON (IAH) 74 64 77 49 64 / 20 40 40 10 10
GALVESTON (GLS) 71 63 72 55 63 / 20 30 40 20 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH LATE TONIGHT FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1135 AM CST SUN DEC 14 2014
.UPDATE...
ISSUED AT 910 AM CST SUN DEC 14 2014
NOT MUCH IMPROVEMENT IN VISIBILITIES EXPECTED THROUGH MONDAY
MORNING AS MILD/MOIST AIRMASS IS LIFTED ACROSS THE REGION.
THEREFORE THE DENSE FOG ADVISORY HAS BEEN EXTENDED THROUGH NOON
MONDAY.
UPDATE ISSUED AT 528 AM CST SUN DEC 14 2014
BECOMING VERY CONCERNED THAT THE DENSE FOG ADVISORY MAY NEED TO BE
EXTENDED FOR THE ENTIRE FORECAST AREA...POSSIBLY INTO MONDAY.
WITH UPPER 40S AND LOW TO MID 50S DEWPOINTS LURKING SOUTH OF THE
AREA NEAR I-80 BEING SHOVED NORTHWARD INTO OUR RELATIVELY SPEAKING
COLDER AIRMASS...ITS POSSIBLE THIS DENSE FOG GOES NOWHERE. ON TOP
OF THAT...LIGHTER WINDS ARE PROGGED TONIGHT...FAVORING LOW
VISIBILITIES. 14.10Z LAV GUIDANCE AT MOST SITES THAT ARE CURRENTLY
EXPERIENCING 1/4 MILE OR LESS VISIBILITIES...SUCH AS RST...CCY AND
MDZ...SHOWS THOSE VISIBILITIES PERSISTING THROUGH 11Z MONDAY...THE
END OF ITS RUN. WE MAY END UP HAVING TO WAIT FOR THE RAIN ON
MONDAY TO HELP IMPROVE VISIBILITIES SOMEWHAT...THOUGH DENSE FOG
COULD EASILY REFORM AFTER THE RAIN TAILS OFF. SOMETIME AFTER
MIDNIGHT MONDAY NIGHT APPEARS WHEN WE CAN FINALLY GET RID OF THE
FOG CONCERN...ACCOMPANYING THE COLD ADVECTION REGIME DEVELOPING
THEN.
HAVE NOT DONE ANY EXTENSIONS TO THE CURRENT ADVISORY...BUT THEY
COULD HAPPEN AT ANYTIME THROUGHOUT THE MORNING. THE HIGHEST
CONFIDENCE FOR THE DENSE FOG TO PERSIST IS ACROSS TAYLOR AND
CLARK COUNTIES...WHICH COINCIDES WITH THE COLDEST FORECAST
READINGS.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 255 AM CST SUN DEC 14 2014
THE MAIN FORECAST CONCERN CONTINUES TO BE THE PRECIPITATION
CHANCES THROUGH THE PERIOD.
LOCAL OBSERVATIONS CONTINUE TO SHOW DENSE FOG WITH VISIBILITIES OF
A QUARTER MILE OR LESS COVERING A GOOD SHARE OF THE AREA. THE
14.05Z RAP BUFKIT SOUNDINGS SUGGEST THE WINDS JUST ABOVE THE
SURFACE MAY DIMINISH A LITTLE BIT THROUGH THE REST OF THE NIGHT
INTO SUNDAY MORNING WITH A SLOWLY DEEPENING SATURATED LAYER. THIS
MAY ALLOW THE DENSE FOG TO BECOME A LITTLE MORE WIDESPREAD AND FOR
THE AREAS THAT HAVE DECENT VISIBILITY TO GO DOWN SOME. PLAN TO
LEAVE THE DENSE FOG ADVISORY IN PLACE WITH NO CHANGES.
STILL DEALING WITH THE ISSUE OF HOW MUCH IF ANY DRIZZLE IS
OCCURRING WITH THE FOG. BASED ON PERSONAL OBSERVATIONS...MUCH LESS
DRIZZLE WAS OCCURRING IN THE LOCAL AREA SATURDAY EVENING THAN
PREVIOUS NIGHTS. THE RAP CONTINUES TO SUGGEST THAT WHAT OMEGA
THERE WILL BE IN THE SATURATED LAYER WILL BE VERY NEAR THE TOP OF
THIS LAYER. THE 14.00Z GFS ALSO CONTINUES TO SHOW JUST SOME VERY
WEAK ISENTROPIC UP GLIDE OF 1 UBAR/S OR LESS ON THE 290K SURFACE.
WILL MAINTAIN THE MENTION OF DRIZZLE FOR THE ENTIRE DAY...BUT WILL
LOWER THE PRECIPITATION CHANCES OF MEASURABLE DOWN TO THE 2O TO 30
PERCENT RANGE. THIS WILL ALSO GIVE AREAS INSTEAD OF WIDESPREAD
DRIZZLE WHICH MOST LIKELY WILL BETTER FIT THE SCENARIO AS WELL.
THE MAIN PRECIPITATION EVENT STILL LOOKS TO MONDAY AND MONDAY
NIGHT. THE UPPER LEVEL LOW LIFTING OUT OF THE DESERT SOUTHWEST IS
EXPECTED TO MOVE INTO THE LOWER MISSOURI RIVER VALLEY TONIGHT AS
ANOTHER UPPER LEVEL LOW DROPS SOUTH FROM CENTRAL CANADA. EVEN
THOUGH THE MAIN UPPER LEVEL RIDGE WILL BE OVER THE EASTERN
CONUS...THE GFS SUGGESTS A SECONDARY RIDGE AXIS WILL EXTEND OFF
THE MAIN RIDGE AXIS ACROSS THE UPPER MIDWEST BETWEEN THE TWO UPPER
LEVEL LOWS. THIS WOULD KEEP THE MAJORITY OF THE FORCING AWAY FROM
THE AREA WITH THE GFS SUGGESTING JUST SOME WEAK QG CONVERGENCE
OCCURRING ACROSS THE WESTERN SECTIONS OF THE AREA WITH JUST THE
VERY WEAK ISENTROPIC UP GLIDE CONTINUING ON THE 290K SURFACE. WILL
TRIM THE RAIN CHANCES BACK TO THE 20 TO 40 PERCENT RANGE FOR THE
EVENING AND THEN ALLOW AN INCREASE TO 60 PERCENT ACROSS THE WEST
FOR LATE TONIGHT.
THE UPPER LEVEL LOW FROM THE SOUTHWEST IS THEN EXPECTED TO MOVE
ACROSS THE AREA MONDAY INTO MONDAY NIGHT BRINGING MODERATE TO
STRONG PV ADVECTION IN THE 500-300 MB ACROSS THE AREA. THE QG
CONVERGENCE WILL BECOME DEEP THROUGH THE 1000-300 MB LAYER AND
SHOULD BE MODERATE IN STRENGTH. THE ISENTROPIC UP GLIDE AHEAD OF
THE LOW WILL ALSO INCREASE WITH THE GFS SHOWING UP TO 10 UBAR/S ON
THE 290K SURFACE BY MONDAY AFTERNOON. WITH THE INCREASED
FORCING...EXPECT THE PRECIPITATION TO BECOME PRETTY WIDESPREAD AND
WILL HAVE 70 TO 80 PERCENT CHANCES FOR THE ENTIRE AREA.
TEMPERATURES WILL CONTINUE TO BE WARM ENOUGH TO KEEP THIS AS ALL
RAIN. THE FORCING WILL NOT START TO DECREASE UNTIL LATE MONDAY
NIGHT...SO WILL CONTINUE WITH THE HIGH PRECIPITATION CHANCES UNTIL
DROPPING THEM DOWN TO ABOUT 60 PERCENT IN THE SOUTHWEST BY LATE
MONDAY NIGHT. BY THIS TIME...THE SURFACE WILL HAVE PASSED BY THE
REGION ALLOWING COLDER AIR TO SPREAD ACROSS THE REGION. THIS WILL
ALLOW FOR A TRANSITION OVER TO SNOW MONDAY NIGHT INTO TUESDAY
MORNING. NOT EXPECTING ANY MIXED PRECIPITATION ISSUES WITH ICE
REMAINING IN THE CLOUDS UNTIL THE PRECIPITATION COMES TO AN END.
SNOWFALL AMOUNTS NOT EXPECTED TO A WHOLE LOT WITH MAYBE UP TO A
HALF INCH OF ACCUMULATION FOR PORTIONS OF SOUTHEAST MINNESOTA
INTO NORTH CENTRAL WISCONSIN.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 255 AM CST SUN DEC 14 2014
FINALLY STARTING TO SEE A CONSENSUS BETWEEN THE MODELS WITH HOW
THE CANADIAN UPPER LEVEL LOW IS HANDLED. THE GFS LOOKS TO HAVE
COME AROUND TO SHOWING THE SAME EVOLUTION THAT THE ECMWF HAS BEEN
SHOWING FOR SEVERAL RUNS. THE UPPER LEVEL LOW IS EXPECTED TO COME
DOWN OVER THE NORTHERN GREAT LAKES TUESDAY NIGHT AND CONTINUE TO
BE PROGRESSIVE AND MOVE OFF THE NORTHEAST COAST THURSDAY NIGHT.
THIS WILL ALLOW HIGH PRESSURE TO BUILD IN AT THE SURFACE BEHIND
THE EARLY WEEK SYSTEM AND THEN REMAIN OVER THE UPPER MIDWEST FOR
THE REMAINDER OF THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1135 AM CST SUN DEC 14 2014
PERSISTENT UNSEASONABLY MILD/MOIST SOUTHERLY AIRFLOW FROM THE
GULF OF MEXICO WILL KEEP IFR/LIFR CONDITIONS IN PLACE ACROSS THE
UPPER MISSISSIPPI RIVER VALLEY INCLUDING KRST/KLSE RIGHT THROUGH
MONDAY. SOME REPRIEVE OF THESE POOR VIS/CIG CONDITIONS MAY TAKE
PLACE MONDAY AFTERNOON AS RAIN MOVES IN AHEAD OF LOW PRESSURE
MOVING OUT OF THE PLAINS.
&&
.CLIMATE...
ISSUED AT 255 AM CST SUN DEC 14 2014
UNSEASONABLY MILD AIR REMAINS OVER THE AREA TODAY. THE RECORD HIGH
AT ROCHESTER IS 52 AND 56 FOR LA CROSSE. WHILE IT DOES NOT LOOK
LIKE LA CROSSE WILL COME CLOSE TO SETTING A RECORD...IT WILL BE
VERY CLOSE FOR ROCHESTER WITH A CURRENT FORECAST OF 51. THE
CLOUDY SKIES AND FOG MAY END UP BEING THE LIMITING FACTOR IF
TEMPERATURES DO NOT WARM AS MUCH AS EXPECTED.
ON THE OTHER HAND...RECORD WARM LOWS ARE ALL BUT CERTAIN FOR
TODAY. THE CURRENT RECORD WARM LOW AT ROCHESTER IS 37 SET IN 1928
WHILE LA CROSSE IS 41 SET IN 1891. THE CURRENT EXPECTATION IS THAT
TEMPERATURES WILL REMAIN IN THE 40S THROUGH MIDNIGHT TONIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...DENSE FOG ADVISORY UNTIL NOON CST MONDAY FOR WIZ017-029-032>034-
041>044-053>055-061.
MN...DENSE FOG ADVISORY UNTIL NOON CST MONDAY FOR MNZ079-086>088-
094>096.
IA...DENSE FOG ADVISORY UNTIL NOON CST MONDAY FOR IAZ008>011-018-019-
029-030.
&&
$$
UPDATE...DAS
SHORT TERM...04
LONG TERM...04
AVIATION...DAS
CLIMATE...04