Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/01/16
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1041 AM PST SAT JAN 30 2016
.SYNOPSIS...LIGHT RAINFALL IS EXPECTED TO TAPER OFF TODAY AS THE
TAIL END OF A SYSTEM MOVES TO THE EAST. THE NEXT SYSTEM WILL
SPREAD RAIN ACROSS THE SOUTHERN HALF OF THE FORECAST AREA ON
SUNDAY...WITH LOCALLY HEAVY RAIN POSSIBLE ALONG THE BIG SUR COAST
AND IN THE SANTA LUCIA MOUNTAINS. BEHIND THE SUNDAY
SYSTEM...BREEZY CONDITIONS ARE EXPECTED LATE SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT...MAINLY NEAR THE COAST. DRY WEATHER RETURNS
MONDAY AND CONTINUES FOR MUCH OF NEXT WEEK.
&&
.DISCUSSION...AS OF 09:01 AM PST SATURDAY...EQUIPMENT UPDATE -
THE KMUX RADAR REMAINS OUT OF SERVICE...AWAITING PARTS TO REPAIR
IT. EARLIEST IT COULD BE REPAIRED WOULD BE THIS AFTERNOON. FOR
RADAR COVERAGE PLEASE USE KDAX TO THE EAST OR KBHX TO THE NORTH.
SHORT TERM CONCERNS CONTINUE TO BE SOME LINGERING SHOWERS THIS
MORNING. LATEST SFC OBS CONTINUE TO INDICATE A FEW TIPS HERE AND
THERE...IN OTHER WORDS WIDELY SCATTERED. IMPACT WILL BE MINIMAL
AS RAINFALL AMOUNTS WILL BE A FEW HUNDREDTHS AT BEST. BY THIS
AFTERNOON...CHANCES FOR PRECIP WILL BE EVEN LESS. CURRENT FORECAST
HAS A WIDESPREAD 15 PCT AND SLIGHT CHANCE FOR SHOWERS. THIS STILL
SEEMS PLAUSIBLE GIVEN THE HRRR AND WRF MODELS SHOW WIDELY
SCATTERED SHOWERS THIS AFTERNOON. LOOKING UPSTREAM...THERE ARE
CURRENTLY SCATTERED SHOWERS WELL NORTH OF THE NORTH BAY SLOWLY
MOVING SOUTH. NO UPDATE IS PLANNED AT THIS TIME.
NEXT WEATHER CONCERN WILL BE THE UPPER LOW DROPPING SOUTH THROUGH
CALIFORNIA. SEVERAL DAYS/RUNS AGO THIS SYSTEM LOOKED VERY
ROBUST...BUT LATEST TRENDS HAVE BEEN LESS FOR THE MTR CWA. THE
BIGGEST IMPACTS WITH RAIN AND WINDS WILL APPEARS TO BE SOUTH OF
THE CWA. HOWEVER...RAIN AND WIND WILL STILL BE POSSIBLE...BUT
MAINLY SOUTH OF MONTEREY BAY. WILL FINE TUNE THIS WITH THE
AFTERNOON FORECAST PACKAGE.
&&
.PREV DISCUSSION...AS OF 3:25 AM PST SATURDAY...
THE NEXT SYSTEM IS FORECAST TO AFFECT THE SOUTHERN PORTION OF OUR
CWA ON SUNDAY AND SUNDAY NIGHT AS AN UPPER LEVEL TROUGH MOVES
ACROSS. LATEST MODEL GUIDANCE...THOUGH...IS INDICATING THAT THE
HEAVIEST RAINFALL WILL OCCUR SOUTH OF OUR AREA. GIVEN EARLIER
UNCERTAINTY...CANNOT COMPLETELY RULE OUT THE POSSIBILITY OF
LOCALLY HEAVY RAINS ALONG THE BIG SUR COAST ON SUNDAY.
RAINFALL WILL END IN MOST AREAS BY LATE SUNDAY AFTERNOON.
BREEZY CONDITIONS ARE EXPECTED TO DEVELOP BY LATE SUNDAY AS A
SURFACE LOW DEVELOPS NEAR LAS VEGAS AND SURFACE HIGH BUILDS
OFFSHORE. THE GRADIENT BETWEEN THE TWO WILL DRIVE BRISK NORTHWEST
WINDS ACROSS THE AREA LATE SUNDAY AND SUNDAY NIGHT. STRONGEST
WINDS ARE EXPECTED TO OCCUR ALONG THE COAST. AT THIS TIME A WIND
ADVISORY DOES NOT SEEM NECESSARY...HOWEVER...THIS COULD CHANGE.
COOLER TEMPERATURES ARE EXPECTED EARLY NEXT WEEK AS A COOLER
AIRMASS SETTLES IN. BY MONDAY NIGHT OVERNIGHT TEMPERATURES ARE
EXPECTED TO DIP DOWN INTO THE 30S IN INLAND VALLEYS. HIGHS WILL
ALSO BE COOL THROUGH MIDWEEK WITH HIGH TEMPS IN THE LOWER 50S. THE
LONGER RANGE MODELS AGREE THAT MOST OF NEXT WEEK WILL BE DRY WITH
PERHAPS JUST A COUPLE OF BRIEF LIGHT RAIN EVENTS.
&&
.AVIATION...AS OF 10:15 AM PST SATURDAY...SKIES ARE QUICKLY
SCATTERING OUT THIS MORNING OVER THE NORTHERN HALF OF THE FORECAST
AREA. SCATTERED HIGH CLOUDS WILL PERSIST ACROSS THE REGION THROUGH
MUCH OF THE FORECAST PERIOD. MODERATE CONFIDENCE.
VICINITY OF KSFO...VFR CONDITIONS ARE EXPECTED TODAY. WESTERLY
WINDS 10 TO 15 KT WILL PREVAIL TODAY.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR CONDITIONS ARE EXPECTED TODAY.
WESTERLY WINDS AROUND 10 KT WILL PREVAIL TODAY.
&&
.MARINE...AS OF 10:26 AM PST SATURDAY...NORTHERLY WINDS ARE
FILLING IN BEHIND A COLD FRONT THIS MORNING. MODERATE BREAKING
WAVES WILL REMAIN A POSSIBILITY ALONG THE COAST TODAY BUT SEAS ARE
ANTICIPATED TO DECREASE THIS AFTERNOON. THE SURFACE PRESSURE
GRADIENT IS EXPECTED TO STRENGTHEN ON SUNDAY BRINGING INCREASING
NORTHERLY WINDS AND DETERIORATING SEA CONDITIONS TO THE COASTAL
WATERS BEGINNING SUNDAY AFTERNOON.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: MM
AVIATION: CW
MARINE: GARCIA
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
901 AM PST SAT JAN 30 2016
.SYNOPSIS...LIGHT RAINFALL IS EXPECTED TO TAPER OFF TODAY AS THE
TAIL END OF A SYSTEM MOVES TO THE EAST. THE NEXT SYSTEM WILL
SPREAD RAIN ACROSS THE SOUTHERN HALF OF THE FORECAST AREA ON
SUNDAY...WITH LOCALLY HEAVY RAIN POSSIBLE ALONG THE BIG SUR COAST
AND IN THE SANTA LUCIA MOUNTAINS. BEHIND THE SUNDAY
SYSTEM...BREEZY CONDITIONS ARE EXPECTED LATE SUNDAY AFTERNOON
THROUGH SUNDAY NIGHT...MAINLY NEAR THE COAST. DRY WEATHER RETURNS
MONDAY AND CONTINUES FOR MUCH OF NEXT WEEK.
&&
.DISCUSSION...AS OF 09:01 AM PST SATURDAY...EQUIPMENT UPDATE -
THE KMUX RADAR REMAINS OUT OF SERVICE...AWAITING PARTS TO REPAIR
IT. EARLIEST IT COULD BE REPAIRED WOULD BE THIS AFTERNOON. FOR
RADAR COVERAGE PLEASE USE KDAX TO THE EAST OR KBHX TO THE NORTH.
SHORT TERM CONCERNS CONTINUE TO BE SOME LINGERING SHOWERS THIS
MORNING. LATEST SFC OBS CONTINUE TO INDICATE A FEW TIPS HERE AND
THERE...IN OTHER WORDS WIDELY SCATTERED. IMPACT WILL BE MINIMAL
AS RAINFALL AMOUNTS WILL BE A FEW HUNDREDTHS AT BEST. BY THIS
AFTERNOON...CHANCES FOR PRECIP WILL BE EVEN LESS. CURRENT FORECAST
HAS A WIDESPREAD 15 PCT AND SLIGHT CHANCE FOR SHOWERS. THIS STILL
SEEMS PLAUSIBLE GIVEN THE HRRR AND WRF MODELS SHOW WIDELY
SCATTERED SHOWERS THIS AFTERNOON. LOOKING UPSTREAM...THERE ARE
CURRENTLY SCATTERED SHOWERS WELL NORTH OF THE NORTH BAY SLOWLY
MOVING SOUTH. NO UPDATE IS PLANNED AT THIS TIME.
NEXT WEATHER CONCERN WILL BE THE UPPER LOW DROPPING SOUTH THROUGH
CALIFORNIA. SEVERAL DAYS/RUNS AGO THIS SYSTEM LOOKED VERY
ROBUST...BUT LATEST TRENDS HAVE BEEN LESS FOR THE MTR CWA. THE
BIGGEST IMPACTS WITH RAIN AND WINDS WILL APPEARS TO BE SOUTH OF
THE CWA. HOWEVER...RAIN AND WIND WILL STILL BE POSSIBLE...BUT
MAINLY SOUTH OF MONTEREY BAY. WILL FINE TUNE THIS WITH THE
AFTERNOON FORECAST PACKAGE.
&&
.PREV DISCUSSION...AS OF 3:25 AM PST SATURDAY...
THE NEXT SYSTEM IS FORECAST TO AFFECT THE SOUTHERN PORTION OF OUR
CWA ON SUNDAY AND SUNDAY NIGHT AS AN UPPER LEVEL TROUGH MOVES
ACROSS. LATEST MODEL GUIDANCE...THOUGH...IS INDICATING THAT THE
HEAVIEST RAINFALL WILL OCCUR SOUTH OF OUR AREA. GIVEN EARLIER
UNCERTAINTY...CANNOT COMPLETELY RULE OUT THE POSSIBILITY OF
LOCALLY HEAVY RAINS ALONG THE BIG SUR COAST ON SUNDAY.
RAINFALL WILL END IN MOST AREAS BY LATE SUNDAY AFTERNOON.
BREEZY CONDITIONS ARE EXPECTED TO DEVELOP BY LATE SUNDAY AS A
SURFACE LOW DEVELOPS NEAR LAS VEGAS AND SURFACE HIGH BUILDS
OFFSHORE. THE GRADIENT BETWEEN THE TWO WILL DRIVE BRISK NORTHWEST
WINDS ACROSS THE AREA LATE SUNDAY AND SUNDAY NIGHT. STRONGEST
WINDS ARE EXPECTED TO OCCUR ALONG THE COAST. AT THIS TIME A WIND
ADVISORY DOES NOT SEEM NECESSARY...HOWEVER...THIS COULD CHANGE.
COOLER TEMPERATURES ARE EXPECTED EARLY NEXT WEEK AS A COOLER
AIRMASS SETTLES IN. BY MONDAY NIGHT OVERNIGHT TEMPERATURES ARE
EXPECTED TO DIP DOWN INTO THE 30S IN INLAND VALLEYS. HIGHS WILL
ALSO BE COOL THROUGH MIDWEEK WITH HIGH TEMPS IN THE LOWER 50S. THE
LONGER RANGE MODELS AGREE THAT MOST OF NEXT WEEK WILL BE DRY WITH
PERHAPS JUST A COUPLE OF BRIEF LIGHT RAIN EVENTS.
&&
.AVIATION...AS OF 3:58 AM PST SATURDAY...THE CURRENT IR SATELLITE
IMAGE CONTINUES TO SHOW THE REMNANTS OF A DEPARTING COLD FRONT
PASSING OVER THE FORECAST AREA THIS MORNING. THE FRONT HAS PASSED
SOUTH OF SAN FRANCISCO AND IS STILL PROMOTING SHOWERS IN THE
MONTEREY BAY AREA. SHOWERS SHOULD COME TO AN END AROUND SUN RISE.
VICINITY OF KSFO...VFR CONDITIONS ARE EXPECTED TODAY WITH CIGS
OVC035-040. WESTERLY WINDS 10 TO 15 KT WILL PREVAIL TODAY.
CONFIDENCE IS MODERATE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...LIFR CONDITIONS WITH LIGHT RAIN WILL
PREVAIL THROUGH AROUND 1500Z AT WHICH POINT RAIN IS ANTICIPATED
TO END AND CIGS ARE ANTICIPATED TO IMPROVE TO IFR. VFR IS EXPECTED
BY LATE MORNING.
CONFIDENCE IS MODERATE.
&&
.MARINE...AS OF 2:58 AM PST SATURDAY...NORTHERLY WINDS ARE
FILLING IN BEHIND A COLD FRONT WHICH IS NOW PASSING OVER THE
SOUTHERN WATERS. MODERATE BREAKING WAVES WILL REMAIN A POSSIBILITY
ALONG THE COAST TODAY BUT SEAS ARE ANTICIPATED TO DECREASE THIS
AFTERNOON. THE SURFACE PRESSURE GRADIENT IS EXPECTED TO STRENGTHEN
ON SUNDAY BRINGING INCREASING NORTHERLY WINDS AND DETERIORATING
SEA CONDITIONS TO THE COASTAL WATERS BEGINNING SUNDAY AFTERNOON.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: MM
AVIATION: LARRY
MARINE: LARRY
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1048 PM PST FRI JAN 29 2016
...GUSTY NORTHWESTERLY WINDS SUNDAY EVENING AND SUNDAY NIGHT
ESPECIALLY NEAR THE COAST...
...WIDESPREAD RAIN EXPECTED FOR MONTEREY AND SAN BENITO COUNTIES
ON SUNDAY. LOCALLY HEAVY RAIN POSSIBLE BIG SUR COAST AND SANTA
LUCIAS...
.SYNOPSIS...PERIODS OF RAIN WILL CONTINUE OVERNIGHT AS A FRONTAL
BOUNDARY MOVES THROUGH THE AREA FROM NORTH TO SOUTH. GENERALLY
LIGHT AMOUNTS OF RAIN ARE EXPECTED. LITTLE ADDITIONAL RAINFALL IS
EXPECTED SATURDAY AND SATURDAY NIGHT. THE NEXT SYSTEM WILL SPREAD
RAIN ACROSS THE SOUTHERN HALF OF THE FORECAST AREA ON
SUNDAY...WITH LOCALLY HEAVY RAIN POSSIBLE ALONG THE BIG SUR COAST
AND IN THE SANTA LUCIA MOUNTAINS. BEHIND THE SUNDAY
SYSTEM...LOCALLY STRONG AND GUSTY NORTHWEST WINDS ARE EXPECTED
LATE SUNDAY AFTERNOON THROUGH SUNDAY NIGHT...MAINLY NEAR THE
COAST. DRY WEATHER RETURNS MONDAY AND CONTINUES FOR MUCH OF NEXT
WEEK.
&&
.DISCUSSION...AS OF 9:05 PM PST FRIDAY...A MOIST...NEARLY
ZONAL...FLOW CONTINUES ACROSS THE EASTERN PACIFIC AND INTO
NORTHERN CA THIS EVENING. FORCING ALONG THE FRONTAL BOUNDARY HAS
PRIMARILY BEEN DUE TO OROGRAPHIC EFFECTS AND SO RAINFALL OF ANY
SIGNIFICANCE HAS MOSTLY BEEN CONFINED TO THE NORTH BAY
MOUNTAINS...EAST BAY HILLS...AND SANTA CRUZ MOUNTAINS.
WATER VAPOR SATELLITE IMAGERY SHOWS A WEAK SHORTWAVE TROUGH
OFFSHORE...RIPPLING ALONG THE FRONTAL BOUNDARY OUT NEAR 40N/130W.
THIS SHORTWAVE WILL ACT TO PUSH THE FRONTAL BOUNDARY SOUTH
OVERNIGHT AND WE CAN EXPECT RAINFALL TO SPREAD OVER MOST AREAS BY
SUNRISE SATURDAY MORNING. BUT AGAIN...MOST FORCING IS EXPECTED TO
BE FROM OROGRAPHIC EFFECTS. THUS...RAINFALL AT LOWER ELEVATIONS
WILL BE LIGHT...WITH LOCALLY MODERATE AMOUNTS LIKELY ON WEST AND
SOUTHWEST-FACING HILLS THROUGHOUT THE AREA. THE LATEST HRRR MODEL
FORECASTS GENERALLY A TENTH OF AN INCH OR LESS OF RAINFALL AT
LOWER ELEVATIONS TONIGHT...WITH UP TO A HALF INCH IN THE HILLS.
THE MODELS AGREE THAT GENERALLY DRY CONDITIONS WILL PREVAIL
SATURDAY AND SATURDAY NIGHT AS WE WILL BE IN BETWEEN SYSTEMS.
HOWEVER...A RELATIVELY MOIST ONSHORE FLOW WILL PERSIST AND SO RAIN
CHANCES WILL CONTINUE. DURING THIS TIME FRAME RAIN WILL BE MOST
LIKELY IN UPSLOPE AREAS OF THE COASTAL MOUNTAINS.
THERE IS STILL QUITE A BIT OF UNCERTAINTY AS TO WHERE THE FOCUS OF
THE NEXT SYSTEM WILL BE. WHAT IS CLEAR IS THAT THAT MOST...IF NOT
ALL...OF THE RAINFALL WITH THE NEXT SYSTEM WILL OCCUR ACROSS THE
SOUTHERN PART OF OUR AREA ON SUNDAY AS A COLD TROUGH MOVING IN
FROM THE NORTHWEST PHASES WITH A SLUG OF MOISTURE MOVING IN FROM
THE WEST. HOWEVER...JUST HOW FAR SOUTH THE FOCUS WILL BE IS STILL
NOT RESOLVED. THE 00Z NAM SPREADS RAIN ACROSS THE SOUTHERN HALF OF
OUR FORECAST AREA ON SUNDAY...WITH LOCALLY HEAVY RAIN PROJECTED
ACROSS MONTEREY AND SAN BENITO COUNTIES THAT DAY...PARTICULARLY
ALONG THE BIG SUR COAST AND IN THE SANTA LUCIAS. HOWEVER...THE 00Z
GFS SHOWS RAINFALL ONLY ACROSS THE SOUTHERN HALF OF MONTEREY AND
SAN BENITO COUNTIES ON SUNDAY...AND ONLY LIGHT TO MODERATE RAIN AT
THAT. THE GFS CONFINES ALL OF THE SIGNIFICANT RAINFALL WITH
SUNDAY`S SYSTEM TO AREAS FORM SLO COUNTY SOUTHWARD. THE 00Z ECMWF
IS NOT YET IN...BUT THE 12Z VERSION OF THAT MODEL CLOSELY
RESEMBLED THE NAM SOLUTION.
RAINFALL WILL END IN MOST AREAS BY LATE SUNDAY AFTERNOON.
BLUSTERY CONDITIONS WILL DEVELOP BY LATE SUNDAY AS A DEEP SURFACE
LOW DEVELOPS NEAR LAS VEGAS AND SURFACE HIGH BUILDS OFFSHORE. THE
GRADIENT BETWEEN THE TWO WILL DRIVE BRISK NORTHWEST WINDS ACROSS
THE REGION FROM LATE SUNDAY THROUGH SUNDAY NIGHT. WINDS WILL
LIKELY PEAK SUNDAY EVENING. STRONGEST WINDS ARE EXPECTED NEAR THE
COAST WHERE LOCAL WIND GUSTS UP TO 50 MPH ARE POSSIBLE. A WIND
ADVISORY MAY BE NEEDED.
COOL CONDITIONS ARE FORECAST EARLY NEXT WEEK. WINDS WILL PROBABLY
PROVIDE ENOUGH MIXING ON SUNDAY NIGHT TO KEEP TEMPS FROM FALLING
TOO MUCH. BUT BY MONDAY NIGHT WE WILL LIKELY SEE TEMPS DROP DOWN
AROUND FREEZING IN THE INLAND VALLEYS.
THE LONGER RANGE MODELS AGREE THAT MOST OF NEXT WEEK WILL BE DRY
WITH PERHAPS JUST A COUPLE OF BRIEF LIGHT RAIN EVENTS.
KMUX RADAR UPDATE: THE KMUX RADAR REMAINS INOPERABLE. A PART
NEEDED TO REPAIR THE RADAR IS ON ORDER AND IS EXPECTED TO ARRIVE
ON SATURDAY. THE EARLIEST THAT THE KMUX RADAR WILL BE RETURNED TO
SERVICE IS SATURDAY AFTERNOON.
&&
.AVIATION...AS OF 10:30 PM PST FRIDAY...FRONTAL SYSTEM MOVING
THE AREA BRINGING LOW CLOUDS WITH AREAS OF REDUCED VISIBILITY AND
LIGHT RAIN. SOME DRIER AIR IN THE LOW AND MID LEVELS WILL ALLOW
FOR RISING CIGS AND EVENTUAL CLEARING SATURDAY MORNING BEHIND THE
FRONT.
VICINITY OF KSFO...MVFR CIGS/VSBYS BUT OCCASIONALLY IFR. LIGHT
RAIN THROUGH 10Z. CONDITIONS IMPROVING AFTER 10Z WITH CIGS RISING
TO AROUND 3000 FEET.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS THROUGH 18Z. OCCASIONAL CHANCE
FOR PRECIP THROUGH 10Z.
&&
.BEACHES...AS OF 10:50 PM PST FRIDAY...LARGE SWELLS STARTING TO
DECREASE THIS EVENING WITH BUOYS REPORTING HEIGHTS IN THE 11 TO
15 FOOT RANGE WITH PERIOD 16 TO 18 SECONDS. HOWEVER EXCESSIVE
WAVE RUN UP CAN STILL BE EXPECTED WITH THESE WAVES WITH LONG
LULLS BETWEEN WAVE SETS...INCREASING THE RISK OF BEING WASHED OFF
OF THE BEACH OR OFF OF ROCKS BY SNEAKER WAVES. LARGE SURF IS
EXPECTED WITH THESE WAVES AS WELL AS STRONG RIP CURRENTS. SWELLS
WILL CONTINUE TO DECREASE SATURDAY.
&&
.MARINE...AS OF 8:48 PM PST FRIDAY...A WEAK FRONTAL SYSTEM WILL
MOVE THROUGH THE AREA TONIGHT WITH LIGHT TO MODERATE NORTHWEST
WINDS DEVELOPING SATURDAY BEHIND THE SYSTEM. A LOW PRESSURE SYSTEM
WILL MOVE INTO CENTRAL CALIFORNIA SUNDAY BRINGING RAIN TO THE
CENTRAL AND SOUTHERN WATERS. NORTHWEST WINDS WILL INCREASE AFTER
THE LOW MOVES INLAND SUNDAY NIGHT AND MONDAY. A LONG PERIOD SWELL
WILL DECREASE SATURDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...HIGH SURF ADVISORY...ENTIRE COAST FROM SONOMA COUNTY
SOUTH TO MONTEREY COUNTY UNTIL 4 AM
SCA...ROUGH BAR ADVISORY FOR SF BAR UNTIL 4 AM
&&
$$
PUBLIC FORECAST: DYKEMA
AVIATION: W PI
MARINE: W PI
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
907 PM PST FRI JAN 29 2016
...GUSTY NORTHWESTERLY WINDS SUNDAY EVENING AND SUNDAY NIGHT
ESPECIALLY NEAR THE COAST...
...WIDESPREAD RAIN EXPECTED FOR MONTEREY AND SAN BENITO COUNTIES
ON SUNDAY. LOCALLY HEAVY RAIN POSSIBLE BIG SUR COAST AND SANTA
LUCIAS...
.SYNOPSIS...PERIODS OF RAIN WILL CONTINUE OVERNIGHT AS A FRONTAL
BOUNDARY MOVES THROUGH THE AREA FROM NORTH TO SOUTH. GENERALLY
LIGHT AMOUNTS OF RAIN ARE EXPECTED. LITTLE ADDITIONAL RAINFALL IS
EXPECTED SATURDAY AND SATURDAY NIGHT. THE NEXT SYSTEM WILL SPREAD
RAIN ACROSS THE SOUTHERN HALF OF THE FORECAST AREA ON
SUNDAY...WITH LOCALLY HEAVY RAIN POSSIBLE ALONG THE BIG SUR COAST
AND IN THE SANTA LUCIA MOUNTAINS. BEHIND THE SUNDAY
SYSTEM...LOCALLY STRONG AND GUSTY NORTHWEST WINDS ARE EXPECTED
LATE SUNDAY AFTERNOON THROUGH SUNDAY NIGHT...MAINLY NEAR THE
COAST. DRY WEATHER RETURNS MONDAY AND CONTINUES FOR MUCH OF NEXT
WEEK.
&&
.DISCUSSION...AS OF 9:05 PM PST FRIDAY...A MOIST...NEARLY
ZONAL...FLOW CONTINUES ACROSS THE EASTERN PACIFIC AND INTO
NORTHERN CA THIS EVENING. FORCING ALONG THE FRONTAL BOUNDARY HAS
PRIMARILY BEEN DUE TO OROGRAPHIC EFFECTS AND SO RAINFALL OF ANY
SIGNIFICANCE HAS MOSTLY BEEN CONFINED TO THE NORTH BAY
MOUNTAINS...EAST BAY HILLS...AND SANTA CRUZ MOUNTAINS.
WATER VAPOR SATELLITE IMAGERY SHOWS A WEAK SHORTWAVE TROUGH
OFFSHORE...RIPPLING ALONG THE FRONTAL BOUNDARY OUT NEAR 40N/130W.
THIS SHORTWAVE WILL ACT TO PUSH THE FRONTAL BOUNDARY SOUTH
OVERNIGHT AND WE CAN EXPECT RAINFALL TO SPREAD OVER MOST AREAS BY
SUNRISE SATURDAY MORNING. BUT AGAIN...MOST FORCING IS EXPECTED TO
BE FROM OROGRAPHIC EFFECTS. THUS...RAINFALL AT LOWER ELEVATIONS
WILL BE LIGHT...WITH LOCALLY MODERATE AMOUNTS LIKELY ON WEST AND
SOUTHWEST-FACING HILLS THROUGHOUT THE AREA. THE LATEST HRRR MODEL
FORECASTS GENERALLY A TENTH OF AN INCH OR LESS OF RAINFALL AT
LOWER ELEVATIONS TONIGHT...WITH UP TO A HALF INCH IN THE HILLS.
THE MODELS AGREE THAT GENERALLY DRY CONDITIONS WILL PREVAIL
SATURDAY AND SATURDAY NIGHT AS WE WILL BE IN BETWEEN SYSTEMS.
HOWEVER...A RELATIVELY MOIST ONSHORE FLOW WILL PERSIST AND SO RAIN
CHANCES WILL CONTINUE. DURING THIS TIME FRAME RAIN WILL BE MOST
LIKELY IN UPSLOPE AREAS OF THE COASTAL MOUNTAINS.
THERE IS STILL QUITE A BIT OF UNCERTAINTY AS TO WHERE THE FOCUS OF
THE NEXT SYSTEM WILL BE. WHAT IS CLEAR IS THAT THAT MOST...IF NOT
ALL...OF THE RAINFALL WITH THE NEXT SYSTEM WILL OCCUR ACROSS THE
SOUTHERN PART OF OUR AREA ON SUNDAY AS A COLD TROUGH MOVING IN
FROM THE NORTHWEST PHASES WITH A SLUG OF MOISTURE MOVING IN FROM
THE WEST. HOWEVER...JUST HOW FAR SOUTH THE FOCUS WILL BE IS STILL
NOT RESOLVED. THE 00Z NAM SPREADS RAIN ACROSS THE SOUTHERN HALF OF
OUR FORECAST AREA ON SUNDAY...WITH LOCALLY HEAVY RAIN PROJECTED
ACROSS MONTEREY AND SAN BENITO COUNTIES THAT DAY...PARTICULARLY
ALONG THE BIG SUR COAST AND IN THE SANTA LUCIAS. HOWEVER...THE 00Z
GFS SHOWS RAINFALL ONLY ACROSS THE SOUTHERN HALF OF MONTEREY AND
SAN BENITO COUNTIES ON SUNDAY...AND ONLY LIGHT TO MODERATE RAIN AT
THAT. THE GFS CONFINES ALL OF THE SIGNIFICANT RAINFALL WITH
SUNDAY`S SYSTEM TO AREAS FORM SLO COUNTY SOUTHWARD. THE 00Z ECMWF
IS NOT YET IN...BUT THE 12Z VERSION OF THAT MODEL CLOSELY
RESEMBLED THE NAM SOLUTION.
RAINFALL WILL END IN MOST AREAS BY LATE SUNDAY AFTERNOON.
BLUSTERY CONDITIONS WILL DEVELOP BY LATE SUNDAY AS A DEEP SURFACE
LOW DEVELOPS NEAR LAS VEGAS AND SURFACE HIGH BUILDS OFFSHORE. THE
GRADIENT BETWEEN THE TWO WILL DRIVE BRISK NORTHWEST WINDS ACROSS
THE REGION FROM LATE SUNDAY THROUGH SUNDAY NIGHT. WINDS WILL
LIKELY PEAK SUNDAY EVENING. STRONGEST WINDS ARE EXPECTED NEAR THE
COAST WHERE LOCAL WIND GUSTS UP TO 50 MPH ARE POSSIBLE. A WIND
ADVISORY MAY BE NEEDED.
COOL CONDITIONS ARE FORECAST EARLY NEXT WEEK. WINDS WILL PROBABLY
PROVIDE ENOUGH MIXING ON SUNDAY NIGHT TO KEEP TEMPS FROM FALLING
TOO MUCH. BUT BY MONDAY NIGHT WE WILL LIKELY SEE TEMPS DROP DOWN
AROUND FREEZING IN THE INLAND VALLEYS.
THE LONGER RANGE MODELS AGREE THAT MOST OF NEXT WEEK WILL BE DRY
WITH PERHAPS JUST A COUPLE OF BRIEF LIGHT RAIN EVENTS.
KMUX RADAR UPDATE: THE KMUX RADAR REMAINS INOPERABLE. A PART
NEEDED TO REPAIR THE RADAR IS ON ORDER AND IS EXPECTED TO ARRIVE
ON SATURDAY. THE EARLIEST THAT THE KMUX RADAR WILL BE RETURNED TO
SERVICE IS SATURDAY AFTERNOON.
&&
.AVIATION...AS OF 4:45 PM PST FRIDAY...FRONTAL SYSTEM MOVING
SLOWLY THROUGH. GENERALLY LOW CLOUDS WILL PREVAIL THROUGH
TONIGHT. SOME DRIER AIR IN THE LOW AND MID LEVELS WILL ALLOW FOR
RISING CIGS AND EVENTUAL CLEARING SATURDAY MORNING BEHIND THE
FRONT.
VICINITY OF KSFO...MVFR WITH CIGS AROUND 1500 FEET AND VSBYS 4-6
MILES WITH OCCASIONAL LIGHT RAIN.
SFO BRIDGE APPROACH...SIMILAR TO KSFO WITH CIGS SLIGHTLY HIGHER.
MONTEREY BAY AREA TERMINALS...MVFR CIGS. CHANCE FOR PRECIP WILL
BE BEST AFTER 06Z TONIGHT AS THE FRONT ARRIVES.
&&
.BEACHES...AS OF 4:50 PM PST FRIDAY...LARGE SWELLS CONTINUE OVER
THE COASTAL WATERS WITH BUOYS REPORTING HEIGHTS IN THE 13 TO 16
FOOT RANGE WITH PERIOD 16 TO 19 SECONDS. EXCESSIVE WAVE RUN UP IS
EXPECTED WITH THESE WAVES WITH LONG LULLS BETWEEN WAVE
SETS...INCREASING THE RISK OF BEING WASHED OFF OF THE BEACH OR OFF
OF ROCKS BY SNEAKER WAVES. LARGE SURF IS EXPECTED WITH THESE WAVES
AS WELL AS STRONG RIP CURRENTS. SWELLS WILL DECREASE TONIGHT AND
SATURDAY.
&&
.MARINE...AS OF 8:48 PM PST FRIDAY...A WEAK FRONTAL SYSTEM WILL
MOVE THROUGH THE AREA TONIGHT WITH LIGHT TO MODERATE NORTHWEST
WINDS DEVELOPING SATURDAY BEHIND THE SYSTEM. A LOW PRESSURE SYSTEM
WILL MOVE INTO CENTRAL CALIFORNIA SUNDAY BRINGING RAIN TO THE
CENTRAL AND SOUTHERN WATERS. NORTHWEST WINDS WILL INCREASE AFTER
THE LOW MOVES INLAND SUNDAY NIGHT AND MONDAY. A LONG PERIOD SWELL
WILL DECREASE SATURDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...HIGH SURF ADVISORY...ENTIRE COAST FROM SONOMA COUNTY
SOUTH TO MONTEREY COUNTY UNTIL 4 AM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 9 PM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 9 PM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 9 PM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM UNTIL 9 PM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 9 PM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 9 PM
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: DYKEMA
AVIATION: W PI
MARINE: W PI
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
822 PM MST SUN JAN 31 2016
.UPDATE...
ISSUED AT 759 PM MST SUN JAN 31 2016
LOW LEVEL FLOW HAS BECOME SELY ALONG THE FRONT RANGE WHICH HAS
SHIFTED STEADIER LIGHT SNOW IN AND NR THE NRN FOOTHILLS WHILE
FURTHER SOUTH ONLY VERY LIGHT SNOW/FLURRIES IS OCCURRING. APPEARS
THIS WILL BE THE NORM OVERNIGHT. QG FIELDS FM THE RAP SUGGEST SNOW
MAY GRADUALLY BECOME STEADIER BY SUNRISE THRU THE LATE MORNING.
MEANWHILE MAIN SYSTEM IS CURRENTLY INTENSIFYING OVER SRN
NEVADA/SRN CA AND WILL MOVE INTO THE FOUR CORNERS AREA BY 18Z MON
AN THEN EASTWARD INTO SERN CO BY MON EVENING. BELIEVE 700 MB LOW
WILL BE MORE CONSOLIDATED AND ALIGNED WITH THE UPPER LEVEL LOW SO
EXPECT INCREASING UPSLOPE FLOW BY EARLY AFTN WHICH WILL LEAD TO
HEAVIER SNOW INTO MON NIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 304 PM MST SUN JAN 31 2016
THE MOIST WESTERLY FLOW ALOFT IS BEGINNING TO BACK TO THE
SOUTHWEST AS AN UPPER TROUGH PUSHES ONSHORE OVER THE WEST COAST TO
DIG INTO THE DESERT SOUTHWEST TONIGHT. LIGHT SNOW HAS ALREADY
BEGUN TO PUSH NORTH INTO THE FORECAST AREA ALONG AN AREA OF
FRONTOGENESIS. THIS SNOW WILL INCREASE AS IT PUSHES NORTH THIS
EVENING...WHICH IS THE REASON FOR STAGGERING THE WINTER STORM
WARNING TIMES. THEN 700 MB FLOW BECOMES SOUTHERLY LATER THIS
EVENING INTO AFTER MIDNIGHT. THIS CAUSES A BIT OF CONCERN AS THIS
CAN DOWNSLOPE OVER THE PALMER DIVIDE AND CAUSE DRYING BETWEEN
THE PALMER RIDGE AND AREAS NORTH OF DENVER...HAVE DECREASED
SNOWFALL AMOUNTS OVERNIGHT IN THIS AREA SLIGHTLY...BUT BELIEVE
ENOUGH LOW LEVEL EASTERLY FLOW THAT MAY CYCLONE AROUND OVER THE
URBAN CORRIDOR SHOULD KEEP SNOW GOING. THE SOUTHERLY FLOW WILL
ALSO HELP INCREASE THE SNOWFALL ALONG THE NORTHERN STATE BORDER
ESPECIALLY BY THE CHEYENNE RIDGE AND THE NORTHERN URBAN CORRIDOR.
ON MONDAY...THE UPPER LOW IS FORECAST TO MOVE FROM NORTHERN
ARIZONA AND THEN BECOME ALMOST VERTICALLY STACKED OVER THE SURFACE
LOW OVER FAR SOUTHEASTERN COLORADO BY EVENING. UPWARD QG VERTICAL
VELOCITIES WILL BECOME MODERATE TO STRONG WHILE WINDS THROUGH A
DEEP LAYER BECOME UPSLOPE AND INCREASE IN SPEED. THIS WILL BRING
HEAVIER SNOWFALL BY LATE MORNING ACROSS THE PLAINS AND ALONG THE
EAST SLOPES OF THE FRONT RANGE AND FOOTHILLS. SNOWFALL RATES
SHOULD BE AROUND HALF AN INCH PER HOUR WITH SOME HIGHER RATES NEAR
THE HIGHER TERRAIN. THE MOUNTAINS WEST OF THE DIVIDE WILL NOT BE
FAVORED IN THE EASTERLY FLOW....SO AMOUNTS WILL BE FAR LESS. WINDS
WILL INCREASE OUT OF THE NORTHEAST DURING THE AFTERNOON OVER THE
PLAINS TO 15 TO 25 MPH WITH GUSTS OF 30 TO 35 MPH TO CREATE
HAZARDOUS TRAVEL CONDITIONS IN BLOWING AND DRIFTING SNOW.
VISIBILITIES WILL BE REDUCED TO LESS THAN A HALF MILE IN THESE
CONDITIONS. EXPECT 4 TO 6 INCHES TO FALL OVER THE PLAINS DURING
MONDAY MORNING AND AFTERNOON...AND 5 TO 10 INCHES IN THE HIGHER
TERRAIN.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 304 PM MST SUN JAN 31 2016
PROLONGED AND STRONG WINTER STORM WILL CONTINUE MONDAY NIGHT
BEFORE FINALLY TAPERING OFF TUESDAY. THE MODELS REMAIN QUITE
CONSISTENT WITH ONLY MINOR FLUCTUATIONS IN EACH MODEL RUN. IT
SHOULD STILL BE NOTED THE STORM IS JUST NOW MOVING ONSHORE SO
BETTER SAMPLING FOR THE EXACT TRACK SHOULD BE AVAILABLE IN THE 00Z
MODEL RUNS. THAT SAID...WE DO HAVE GOOD CONFIDENCE IN THE OVERALL
TRACK OF THE STORM BASED ON CURRENT SATELLITE IMAGERY. THE
EXPECTED TRACK TAKES THE MID LEVEL CIRCULATION CENTER IS EXPECTED
TO MOVE EAST/NORTHEAST FROM THE NORTHEAST CORNER OF NEW MEXICO
TOMORROW EVENING INTO SOUTHWEST KANSAS BY EARLY TUESDAY MORNING.
THERE IS STILL GOOD UPWARD Q-G LIFT AND THE BEST UPSLOPE COMPONENT
AS WELL AS INSTABILITY BELOW 600 MB THROUGH MONDAY EVENING. THOSE
FAVORABLE PARAMETERS START TO FADE OVERNIGHT MONDAY NIGHT. AS A
RESULT...THE HEAVIEST SNOW OF THIS EVENT SHOULD CONTINUE INTO
TOMORROW EVENING BEFORE STARTING A SLOW DECREASE LATE MONDAY NIGHT
INTO TUESDAY MORNING. ON THE EASTERN PLAINS...NORTHEAST WINDS 15
TO 25 MPH WITH GUSTS AROUND 35 MPH WILL LIKELY PRODUCE
CONSIDERABLE BLOWING AND DRIFTING SNOW. AT THIS TIME...WINDS ARE
JUST SHY OF BLIZZARD CRITERIA BUT WILL HAVE TO WATCH THIS
POTENTIAL MAINLY ALONG/EAST OF A LINE FROM AKRON TO LIMON AS
EXPECTED DEPTH OF SNOW AND DRIER NATURE OF SNOW ON THE BACK SIDE
OF STORM WILL ALSO ADD TO THE AMOUNT OF BLOWING/DRIFTING.
EXPECTED STORM TOTALS WILL BE QUITE HIGH OVER MOST OF THE FORECAST
AREA. REASONABLE AGREEMENT BETWEEN 7 AND 14 INCHES WILL FALL OVER
MOST OF THE PLAINS DURING THIS LONG DURATION EVENT...HEAVIEST
NEAR THE FOOTHILLS AND I-70 CORRIDOR EASTWARD ACROSS THE PLAINS.
IN THE FOOTHILLS AND FRONT RANGE MOUNTAINS...INITIAL EXPECTATIONS
ARE FOR 10-24 INCHES...WITH THE HEAVIER TOTALS ON EAST FACING
SLOPES OF THE FRONT RANGE. MEANWHILE...THE HIGH MOUNTAIN VALLEYS
OF GRAND AND JACKSON COUNTIES ARE LIKELY TO BE LARGELY DOWNSLOPED
MAINLY LATER IN THIS EVENT AS EASTERLY COMPONENT STRENGTHENS.
IT SHOULD BE NOTED SOME MODELS ARE HIGHER THAN THE FORECAST
TOTALS...BUT SOME BIAS IS NORMALLY NOTED ON THE HIGH SIDE...AND
NOT SURE HOW EFFICIENT DENDRITIC GROWTH WILL BE OUTSIDE OF THE
PERIODS OF HEAVIER SNOWFALL. WILL CERTAINLY MONITOR AND ADJUST THE
FORECAST AS EVENT UNFOLDS AND MORE CONFIDENCE IS HOPEFULLY
ACHIEVED AFTER THE SYSTEM MOVES ONSHORE.
ALL THAT SAID...DIFFICULT TRAVEL CONDITIONS ARE EXPECTED BOTH BY
ROAD AND AIR WITH DELAYS/CANCELLATIONS POSSIBLE THROUGH TUESDAY.
SOME RURAL OR SECONDARY ROADS MAY HAVE DIFFICULT TRAVEL BY MONDAY
NIGHT DUE TO SNOW DEPTH...AS WELL AS DRIFTING OUT ON THE EASTERN
PLAINS.
BY TUESDAY NIGHT...CONDITIONS IMPROVE WITH ONLY SOME LINGERING
LIGHT SNOW IN THE MOUNTAINS.
THE REST OF THE WEEK INTO NEXT WEEKEND WILL FEATURE NORTHWEST FLOW
ALLOWING EMBEDDED SHORT WAVES TO BRING A COUPLE PERIODS OF SNOW TO
THE MOUNTAINS AND BRIEF COOLDOWNS FOR THE PLAINS. ONE OF THESE
APPEARS LIKELY FOR LATE THURSDAY NIGHT INTO FRIDAY...WITH ANOTHER
TOWARD NEXT SUNDAY. OVERALL TEMPERATURES WILL RUN BELOW NORMAL
WITH FRESH SNOW COVER AND CHILLY NORTHWEST FLOW ALOFT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 759 PM MST SUN JAN 31 2016
ONLY EXPECT PERIODS OF VERY LIGHT SNOW OVERNIGHT WITH ADDITIONAL
ACCUMULATIONS UNDER AN INCH. INTENSITY COULD INCREASE SOME BY
SUNRISE HOWEVER HEAVIEST SNOWS WILL PROBABLY HOLD OFF UNTIL AROUND
NOON WHICH WILL CONTINUE INTO MON NIGHT AS STG STORM SYSTEM MOVES
INTO SERN CO. TOTAL SNOWFALL AT DIA WILL BE IN THE 8" TO 12"
RANGE WITH HIGHER AMOUNTS POSSIBLE AT APA AND BJC.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO NOON MST TUESDAY
FOR COZ042-044-048>051.
WINTER STORM WARNING UNTIL NOON MST TUESDAY FOR COZ033>037.
WINTER STORM WARNING UNTIL NOON MST TUESDAY FOR COZ038>041-043-
045>047.
&&
$$
UPDATE...RPK
SHORT TERM...KRIEDERMAN
LONG TERM...BARJENBRUCH
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS WICHITA KS
922 PM CST SUN JAN 31 2016
.SYNOPSIS...
ISSUED AT 237 PM CST SUN JAN 31 2016
CURRENTLY HAVE ONE SHORTWAVE APPROACHING THE WESTERN GREAT LAKES
WITH ANOTHER MORE VIGOROUS PIECE OF ENERGY DIGGING OVER
NORTHERN/CENTRAL CA. AT THE SURFACE...A COLD FRONT STRETCHES FROM
NORTHERN IL DOWN INTO NORTHEAST TX.
&&
.UPDATE...
ISSUED AT 917 PM CST SUN JAN 31 2016
THE SIGNIFICANT STORM SYSTEM THAT WILL AFFECT THE PLAINS FOR MON
THRU TUE HAS FINALLY MOVED ON SHORE OF SRN CA. SO ITS FINALLY BEING
SAMPLED BETTER BY UPPER AIR NETWORK AND MODELS. WITH THAT
SAID...LATEST MODEL RUNS AND CURRENT FORECAST ARE ON TRACK. THIS
HAS INCREASED CONFIDENCE IN THE GOING FORECAST...WITH JUST SOME
MINOR TIMING ISSUES. ONE OF THOSE TIMING ISSUES WILL BE THE
INITIAL ONSET OF WIDELY SCATTERED LIGHT PRECIP CHANCES IN THE
MORNING HOURS ON MON. LATEST RAP HI-RES GUIDANCE SUGGESTS PRECIP
MAY BE DELAYED UNTIL MID MORNING MON FOR AREAS WEST OF I-135 AS
LOW LEVELS WILL BE SLOW TO SATURATE. SO HAVE ADJUSTED POPS SOME TO
SLOW POPS UNTIL THE LATE MORNING HOURS. CERTAINLY THINK POPS ARE
LIKELY FOR CENTRAL KS FOR MON AFTERNOON. TIMING OF THE HEAVIEST
SNOW ACROSS NORTH CENTRAL KS STILL LOOKS ON TRACK FOR MON EVENING
THRU TUE MORNING.
KETCHAM
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 237 PM CST SUN JAN 31 2016
POTENT UPPER TROUGH WILL CONTINUE TO DIG OVER THE DESERT SW
TONIGHT AND WILL START TO MOVE OUT ACROSS THE SOUTHERN HIGH PLAINS
MON. GFS AND ECMWF REMAIN CONSISTENT AS THEY HAVE OVER THE LAST
FEW DAYS WHICH DOES LEAD TO SOME CONFIDENCE IN HEAVY SNOW LOCATION
AND TIMING. THE 12Z RUN OF THE NAM HAS STARTED TO TREND SLIGHTLY
NORTH COMPARED TO IT`S PREVIOUS RUNS BUT IS STILL A BIT FURTHER
SOUTH AND COLDER THAN THE GFS AND ECMWF SOLUTIONS.
CURRENTLY EXPECTING PRECIP TO OVERSPREAD WESTERN KS MON...GETTING
INTO OUR CENTRAL KS COUNTIES MON AFTERNOON. THERMAL PROFILES WOULD
SUGGEST THAT TEMPS WILL BE TOO WARM FOR ACCUMULATING SNOW MON
AFTERNOON AS STRONG LOW LEVEL WARM ADVECTION OFFSETS WET BULB
PROCESSES. MON NIGHT STILL LOOKS LIKE WHEN THE BULK OF SNOW WILL
IMPACT CENTRAL KS. CURRENTLY THINK THERE WILL BE AROUND A 12-15
HOUR PERIOD OF SNOW GENERALLY NW OF A KGBD-KSLN LINE WITH CROSS
SECTIONS SUGGESTING AROUND 4-5 HOURS WILL HAVE GOOD LIFT IN THE
DENDRITIC ZONE ALONG WITH SOME SLANTWISE INSTABILITY...RESULTING
IN AROUND 1 INCH PER HOUR RATES. HOWEVER...LOCATIONS JUST TO OUR
NW WILL SEE A MUCH MORE PROLONGED PERIOD OF GOOD SNOW GROWTH
PRODUCTION...RESULTING IN THE HIGHEST SNOW TOTALS WITH THIS
EVENT. THE BETTER FRONTOGENESIS IN A 600-700MB LAYER ALSO
CONTINUES TO REMAIN NORTH OF THE FORECAST AREA. NORTH WINDS
CONTINUE TO LOOK STRONG MON NIGHT INTO TUE...WITH GUSTS IN THE 35
TO 40 MPH RANGE NOT OUT OF THE QUESTION...WHICH SHOULD RESULT IN
SOME BLOWING AND DRIFTING OF SNOW.
SO FOR NOW...WILL GO WITH SNOW TOTALS FAIRLY CLOSE TO WHAT THE
PREVIOUS FORECAST HAD WITH AROUND 9 INCHES OVER FAR NW RUSSELL
COUNTY TAPERING QUICKLY TO LESS THAN 2 INCHES SE OF A LINE FROM
LYONS TO SALINA. FOR NOW WILL UPGRADE THE CURRENT WATCH TO A
WARNING WHICH IS WHERE WE STILL HAVE THE HIGHEST CONFIDENCE IN
AMOUNTS 6 INCHES OR GREATER. WHILE IT`S LIKELY THERE WILL BE AN
ADVISORY FOR A FEW COUNTIES SOUTH OF THE WARNING...WANT TO ALLOW
SOME LEEWAY FOR FUTURE SHIFTS TO ADD A COUNTY OR 2 TO THE WARNING
IF THIS STORM SYSTEM CHANGES ITS TRACK SLIGHTLY. BASICALLY WANT TO
AVOID FLIP FLOPPING HEADLINES.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 237 PM CST SUN JAN 31 2016
SNOW SHOULD COME TO AN END TUE EVENING AS THE TROUGH QUICKLY DEPARTS
TO THE NORTHEAST. VERY COLD AIRMASS IS THEN FORECAST TO SPILL
ACROSS THE PLAINS WITH HIGHS WED NOT EXPECTED TO GET MUCH ABOVE
FREEZING FOR MUCH OF THE AREA. WE THEN GET INTO NW FLOW ALOFT
ACROSS THE PLAINS WITH A SERIES OF FAST MOVING IMPULSES DIVING
ACROSS THE FORECAST AREA. SO WOULDN`T BE SHOCKED IF FLURRIES OR
LIGHT SNOW IS INSERTED WED OR THU NIGHT INTO FRI...BUT CONFIDENCE
IS HIGH THAT WE ARE NOT LOOKING AT A SIGNIFICANT SNOW EVENT.
LAWSON
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 557 PM CST SUN JAN 31 2016
COLD FRONT HAS PUSHED WELL SOUTH OF THE FORECAST AREA AT THIS
TIME WITH NORTH WINDS ACROSS THE REGION...WITH A WEAK RIDGE OF HIGH
PRESSURE MOVING ACROSS THE NRN PLAINS. THIS WILL LEAD TO WINDS
GRADUALLY SHIFTING TO THE NORTHEAST AND EAST TONIGHT AS THIS RIDGE
MOVES QUICKLY BY.
HE WIND SHIFT TO THE EAST WILL BE IN RESPONSE TO A SIGNIFICANT STORM
SYSTEM MOVING INTO THE SOUTHERN ROCKIES TONIGHT INTO EARLY MON. AS
THIS SYSTEM APPROACHES THE PLAINS...EXPECT CEILINGS TO GRADUALLY
DECREASE IN HEIGHT FOR THE MORNING HOURS ON MON....WITH SATURATION
IN THE MID LAYERS INCREASING ENOUGH FOR A LIGHT RAIN CHANCE BY
AROUND 16Z/MON FOR THE KRSL AND KGBD TAF SITES. EXPECT A LOWERING
OF THE CEILINGS TO MVFR FOR BOTH KRSL AND KGBD AS SATURATION
CONTINUES TO INCREASE BY AROUND 21Z/MON.
COULD POTENTIALLY SEE MVFR CIGS ACROSS OF SOUTH CENTRAL KS LATE MON
AFTERNOON AS WELL...BUT THINK THIS WILL OCCUR AFTER THE HOURS OF
THIS TAF ISSUANCE. BUT CERTAINLY EXPECT MVFR CIGS IN MOST LOCATIONS
BY MON EVENING...WITH THE WORST TAF CONDITIONS IN CENTRAL KS BY MON
EVENING.
KETCHAM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 33 51 32 36 / 10 30 80 40
HUTCHINSON 31 48 31 34 / 10 50 80 50
NEWTON 32 48 32 36 / 10 40 80 50
ELDORADO 33 51 34 40 / 10 30 80 30
WINFIELD-KWLD 32 54 37 41 / 10 20 70 20
RUSSELL 29 41 27 29 / 10 80 100 90
GREAT BEND 29 42 28 30 / 10 80 90 70
SALINA 31 44 30 32 / 10 60 90 70
MCPHERSON 31 47 31 34 / 10 50 80 60
COFFEYVILLE 34 57 43 51 / 10 10 70 20
CHANUTE 32 53 41 46 / 10 10 80 30
IOLA 32 52 40 45 / 10 10 80 40
PARSONS-KPPF 33 55 42 48 / 10 10 70 30
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM 6 PM MONDAY TO 6 PM CST TUESDAY FOR
KSZ032-033-047.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
1015 AM EST SAT JAN 30 2016
.SYNOPSIS...
HIGH PRESSURE MOVES ACROSS NEW ENGLAND TODAY AND OFFSHORE INTO THE
ATLANTIC TONIGHT. A WARM FRONT WILL LIFT NORTHEAST ACROSS THE
REGION TONIGHT. EXPECT WARMER TEMPERATURES BEGINNING ON SUNDAY AND
LASTING THROUGH MUCH OF THE COMING WEEK. LOW PRESSURE WILL MOVE
OUT OF THE GREAT LAKES AND THROUGH THE SAINT LAWRENCE VALLEY ON
MONDAY... DRAGGING A COLD FRONT ACROSS NEW ENGLAND. THIS WILL COOL
TEMPERATURES SOMEWHAT BUT IT WILL STILL BE ABOVE NORMAL. A LARGER
STORM SYSTEM IS EXPECTED TO DEVELOP OVER THE MIDWEST NEXT WEEK AND
MOVE NORTHEAST THROUGH THE CENTRAL GREAT LAKES AND DEEP INTO
CANADA ON WEDNESDAY. THIS WILL SEND ANOTHER FRONTAL SYSTEM THROUGH
NEW ENGLAND ON WEDNESDAY AND WEDNESDAY NIGHT. COOLER HIGH PRESSURE
WILL BUILD IN OUT OF THE NORTHWEST BEHIND THE FRONT FOR THURSDAY.
LOW PRESSURE WILL DEVELOP OFF THE MID ATLANTIC COAST AND MOVE
NORTHEAST OFF THE COAST OF NEW ENGLAND ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1010 AM UPDATE...HAVE UPDATED THE FORECAST FOR THE REST OF THE DAY
AND INTO THIS EVENING BASED ON LATEST TRENDS IN OBSERVATIONAL AND
MODEL DATA. HAVE INCREASED POPS FOR VERY LATE THIS AFTERNOON AND
EVENING FOR NORTHERNMOST NH AND THE WESTERN ME MOUNTAINS BASED ON
A BLEND OF LATEST MODEL GUIDANCE SUCH AS THE HRRR AND SREF. SHOULD
BE A BAND OF MEASURABLE SNOW/SNOW SHOWERS THAT MOVES THROUGH THAT
AREA A FEW HOURS EITHER SIDE OF 00Z. SOME MODEL DATA HINT AT
DEVELOPMENT OF SNOW SHOWERS /MAYBE SOME RAIN SHOWERS ON IMMEDIATE
COAST/ ON THE COASTAL PLAIN...ESPECIALLY THE MIDCOAST THIS
EVENING AS LOW LEVEL JET BEGINS TO STRENGTHEN. HAVE BLENDED IN
SOME LOWER POPS THERE TO ACCOUNT FOR THIS POSSIBILITY.
OTHERWISE...EXPECT INCREASING CLOUDS THE REST OF THE DAY.
PREVIOUSLY...
HIGH PRESSURE BUILDS IN BRIEFLY TODAY... BRINGING AN END TO THE
LIGHT SNOW. TEMPERATURES WILL BE A FEW DEGREES ABOVE NORMAL WITH
HIGHS IN THE 30S TO NEAR 40 DEGREES. CLOUD COVER STILL STUCK TO
THE NORTHWEST OF THE MOUNTAINS SHOULD DISSIPATE AS THE DAY GOES ON
AND WINDS SHIFT FROM NORTHWEST TO SOUTH OR SOUTHWEST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
7AM UPDATE...
CLOUD COVER STUCK TO THE WEST OF THE MOUNTAINS HAS SHOWN SIGNS OF
RETREATING OVER THE PAST FEW HOURS AS DRIER AIR WORKS ITS WAY IN
FROM THE SOUTHWEST AND HELPS MIX OUT THOSE STUBBORN CLOUDS. IT
WILL NOT LIKELY BE SUNNY FOR LONG AS MID AND HIGH LEVEL CLOUDS
ARE ALREADY SPILLING INTO NEW YORK STATE. MADE A FEW ADJUSTMENTS
TO HOURLY TEMPERATURES BUT OTHERWISE NO SIGNIFICANT CHANGES WERE
NEEDED TO THE CURRENT FORECAST.
ORIGINAL DISCUSSION...
HIGH PRESSURE MOVES EAST TONIGHT WITH A SHORTWAVE TROUGH LIFTING
THROUGH ONTARIO AND QUEBEC. THIS FEATURE MAY BE JUST CLOSE ENOUGH
TO PROVIDE A FEW LIGHT SNOW SHOWERS IN NORTHERN AREAS TONIGHT BUT
NOT EXPECTING MUCH ACCUMULATION IF IT DOES OCCUR. THE MAIN EFFECT
WILL BE A SHIFT TO SOUTHERLY WINDS WITH WARMER AIR MOVING IN FROM
THE SOUTH. BY SUNDAY TEMPERATURES WILL BE WELL INTO THE 40S ACROSS
THE ENTIRE AREA. INCREASING DEWPOINTS AS WELL SHOULD ALLOW FOR
SOME MELTING OF THE REMNANT SNOW PACK.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
NEXT WEEK CAN BEST BE CHARACTERIZED BY WARM AND WET CONDITIONS.
THERE IS A SMALL CHANCE FOR A COASTAL LOW BRINGING SNOW TO THE
REGION BY FRIDAY.
ANOTHER AREA OF LOW PRESSURE THIS WINTER WILL PASS TO OUR
WEST...LEAVING NORTHERN NEW ENGLAND ON THE WARM SIDE OF THE
EQUATION. THERE MAY BE A MIX AT THE ONSET OF THE PRECIPITATION OVER
FAR NORTHERN AREAS...OTHERWISE THIS WILL BE A RAIN EVENT WITH MILD
TEMPERATURES.
READINGS QUICKLY SOAR THROUGH THE 40S ON MONDAY DESPITE THE
PASSAGE OF A COLD FRONT WITH SOME AREAS OVER SOUTHERN NEW
HAMPSHIRE TOPPING OUT AT 50 DEGREES.
AFTER A BRIEF RIDGE OF HIGH PRESSURE ON TUESDAY...ANOTHER LOW
PRESSURE WILL UNDERGO CYCLOGENESIS AND CROSS OVER THE GREAT LAKES
ON WEDNESDAY. THIS WILL BRING A MIX OF PRECIPITATION INTO
NORTHERN AREAS...TO BE FOLLOWED BY RAIN IN ALL SECTIONS.
SIMILAR TO TUESDAY...HIGH PRESSURE WILL BRIEFLY MAKE AN
APPEARANCE ON THURSDAY. THIS WILL BE FOLLOWED BY LOW PRESSURE OFF
THE MID ATLANTIC COASTLINE MOVING NORTHEAST ON FRIDAY. THE GFS IS
MORE VIGOROUS WITH THIS SYSTEM AS COMPARED TO THE NEW EURO RUN.
CONFIDENCE LEVELS ARE LOW WITH THE FORECAST TRACK OF THE SURFACE
LOW AS THERE IS A LARGE SPREAD IN THE ENSEMBLE GUIDANCE.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...MAINLY VFR EXPECTED TODAY EXCEPT PERHAPS IN THE
MOUNTAINS WHERE SNOW SHOWERS MAY LOWER CONDITIONS 3 HOURS EITHER
SIDE OF 00Z THIS EVENING.
LONG TERM...CONDITIONS LOWER TO IFR WITH LOCALIZED LIFR ON SUNDAY
NIGHT WITH LOW PRESSURE PASSING BY TO OUR WEST. THIS WILL CONTINUE
INTO MONDAY AS A COLD FRONT CROSSES THE REGION. AREAS OF IFR AND
LIFR TO RETURN ONCE AGAIN WEDNESDAY AND WEDNESDAY NIGHT WITH YET
ANOTHER AREA OF LOW PRESSURE PASSING BY WELL TO OUR WEST.
&&
.MARINE...
SHORT TERM...HAVE EXTENDED THE SCA FOR THE OCEAN WATERS THROUGH
MIDDAY SUNDAY BASED ON SEAS THAT ARE STILL EXPECTED TO BE AT OR
GREATER THAN 5 FT. OTHERWISE...ADDED CASCO BAY TO THE SCA FOR
TONIGHT ONLY AS FREQUENT GUSTS AROUND 25 KT ARE EXPECTED. A FEW
LOW-END GALE FORCE GUSTS POSSIBLE ON THE OCEAN WATERS TONIGHT.
CONDITIONS SUBSIDE SUNDAY.
LONG TERM...THE GRADIENT INCREASES SUNDAY NIGHT FROM THE
SOUTHWEST...ALLOWING WINDS TO INCREASE FROM THE SOUTHWEST INTO THE
SCA RANGE. GALE FORCE WINDS ARE POSSIBLE WEDNESDAY AS LOW PRESSURE
PASSES OVER THE GREAT LAKES AND INTO CANADA.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EST SUNDAY
FOR ANZ151-153.
SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO NOON EST
SUNDAY FOR ANZ150-152-154.
&&
$$
NEAR TERM UPDATE...EKSTER
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
955 PM EST SUN JAN 31 2016
.UPDATE...
ISSUED AT 952 PM EST SUN JAN 31 2016
WIDESPREAD LGT RAIN HAS EXITED OUT OF EASTERN CWA AS UPPER JET
STREAK AND SHORTWAVE AND ASSOCIATED SFC LOW MOVE EAST. LEFT IN THE
WAKE OF THAT SYSTEM IS WEAK SFC TROUGH OVER LK SUPERIOR WITHIN BROAD
TROUGHING ALOFT. A COUPLE OF VERY WEAK SHORTWAVES MOVING THROUGH IN
THE FLOW ARE TRIGGERING LOOSELY ORGANIZED AREAS OF LGT PRECIP. ONE
IS OVER EASTERN LK SUPERIOR WITH SOME ECHOES SHOWING UP ON THE RADAR
LAST COUPLE HOURS. MOST LIKELY ISOLD SNOW SHOWERS IN THAT BAND.
OTHER AREA OF PRECIP IS OVER NORTHEAST MN. HAVE HAD A COUPLE OBS
WITH LGT SNOW 4SM-7SM WITHIN THOSE SCATTERED RADAR ECHOES. LATEST
HRRR MODEL HAS LATCHED ON TO THE PRECIP CHANCES FOR THE FAR
NORTHEAST CWA. SOUNDINGS WOULD SUGGEST MAINLY SNOW AS MOIST LAYER IS
UP TO 800- 750MB WITH TEMPS IN THAT LAYER -12C OR SO. INCREASED POPS
SLIGHTLY OVER EAST OVERNIGHT AS THIS WAVE/LGT PRECIP MOVES THROUGH.
KEPT THEME OF ISOLD SNOW SHOWERS OR FREEZING DRIZZLE OVER WEST AS
PRECIP OVER NORTHEAST MN MOVES IN WITH HRRR INDICATING TEMPS IN
MOIST LAYER -8C TO -10C.
BOTH OF THESE DISTURBANCES SEEM TO HELP PUSH THE SFC TROUGH OVER LK
SUPERIOR ALONG INTO NORTHERN CWA BY DAYBREAK MON. SLIGHTLY COOLER
BEHIND THIS TROUGH /TEMPS IN MOIST LAYER LOWER THAN -10C BUT NOT BY
MUCH/. DID KEEP ISOLD SNOW SHOWERS FOR LK SUPERIOR SNOW BELTS INTO
MON. ANOTHER SHORTWAVE WORKING THROUGH BY MID MORNING COULD HELP
THESE SNOW SHOWERS ALONG.
FINALLY...CONCERNING THE UPCOMING POTENTIAL WINTER STORM TAKING A
QUICK LOOK AT 00Z NAM THE TIMING IS STILL ON TRACK FOR THE MODERATE
TO HEAVY SNOW TUE AFTN. STRIPE OF HEAVIEST QPF 18Z WED THROUGH 06Z
WED OVER 0.75 INCHES STAYS CENTERED ON FAR SCNTRL...VCNTY OF MNM.
LESSER AMOUNTS UP TO 0.50 EXTEND TO IMT-ESC-ISQ. 21Z SREF MEAN QPF
DURING THE WATCH PERIOD 18Z TUE THROUGH 18Z WED IS SOLID 0.60 INCH
OVER WATCH AREA WITH POCKET OF 0.75 INCHES NCNTRL UPR MICHIGAN
UPSLOPE AREAS. THE TWO MAIN SHORTWAVE PLAYERS ARE JUST PHASING OVER
SOUTHERN CA THIS EVENING AS UPPER JET CARVES OUT TROUGH...SO RAOBS
SHOULD BEGIN TO SAMPLE THIS SYSTEM MORE THOROUGHLY FM HERE ON OUT. &&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 306 PM EST SUN JAN 31 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW ACROSS THE
CONUS. STRONG SRN STREAM SHORTWAVE MOVING ONSHORE OF CA WILL BE THE
FEATURE OF INTEREST FOR A GREAT LAKES WINTER STORM MID WEEK AS IT
TRACKS E...THEN NE. SHORTWAVE OF INTEREST IN SHORT TERM IS NOW
MOVING E ACROSS NORTHERN IOWA. SOME LIGHT PCPN HAS DEVELOPED ACROSS
ERN IA AND MAINLY THE SE HALF OF WI THIS AFTERNOON WITH THIS
FEATURE...AIDED BY UPR DIVERGENCE IN RIGHT ENTRANCE OF UPPER JET NOW
MOVING INTO SRN QUEBEC.
SHORTWAVE OVER IA WILL CONTINUE TO AMPLIFY AS IT MOVES INTO THE WRN
GREAT LAKES THIS EVENING. IN TURN...ASSOC SFC WILL TRACK FROM SRN
LAKE MI TO NEAR THE GEORGIAN BAY THIS EVENING. DEEP LAYER FORCING
SPREADING INTO THE AREA IN ASSOCIATION WITH APPROACHING AMPLIFYING
SHORTWAVE PER MID-LVL Q-VECT CONV AND 700-600 MB FGEN HAS HELPED
SUPPORT SOME LIGHT RAIN OVER SCNTRL AND SE CWA THIS AFTERNOON AS
NOTED ON AREA WEBCAMS.
BASED ON FCST SOUNDINGS AND 1000-850MB THICKNESS FIELD...ANY PCPN
OVER THE SE FCST AREA SHOULD TURN FROM RAIN OR RAIN/SNOW MIX TO
MOSTLY SNOW BY THIS EVENING AS LOW-LEVELS FINALLY BEGIN TO COOL. NOT
EXPECTING MUCH IF ANY SNOW ACCUMULATION (A FEW TENTHS) DUE TO MIX OF
PCPN AND ABOVE FREEZING SFC TEMPS THIS AFTERNOON...EVEN IF PCPN
CHANGES TO ALL SNOW.
TONIGHT...SHORTWAVE FROM NEAR IA MOVES THROUGH THE UPPER GREAT LAKES
WHILE A SFC TROF DROPS S ACROSS LAKE SUPERIOR AND INTO MOST OF NRN
UPPER MI BY 12Z MON. FCST SOUNDINGS SUGGEST MOISTURE DEPTH MAY NOT
BE SUFFICIENT TO REACH SUB -10C TEMPS CONSISTENTLY...ESPECIALLY IN
THE EVENING. SO THERE IS SOME POTENTIAL FOR -FZDZ AT THAT TIME IF
PCPN OCCURS. THE GENERAL LACK OF SYNOPTIC FORCING AND MARGINAL AT
BEST INSTABILITY OVER THE LAKE SUGGESTS NOTHING MORE THAN 20-30 PCT
POPS FOR -SN/-FZDZ ARE WARRANTED NEAR LAKE SUPERIOR TONIGHT. EXPECT
MIN TEMPS IN THE LOWER TO MID 20S.
MONDAY...WEAK WINDS AND SHEAR WITHIN CONVECTIVE BOUNDARY LAYER ALONG
WITH MARGINAL INSTABILITY WILL AGAIN LIMIT POPS TO GENERALLY NO MORE
THAN 30 PCT FOR WNW SNOWBELTS. MAX TEMPS WILL RANGE FROM THE MID TO
UPPER 20S NORTH TO LOWER 30S SOUTH CENTRAL UNDER MOSTLY CLOUDY
SKIES.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 514 PM EST SUN JAN 31 2016
A BROAD MID/UPPER LEVEL TROUGH OVER THE WEST INTO CNTRL CONUS WILL
GIVE WAY TO RIDGING OVER WRN NOAM RESULTING IN NW FLOW INTO THE NRN
LAKES AND INTRUSIONS OF ARCTIC AIR INTO OR JUST TO THE NE OF THE
REGION. THE MAIN WEATHER STORY WILL BE THE WINTER STORM MOVING OUT
OF THE PLAINS INTO THE GREAT LAKES TUE INTO WED.
MONDAY NIGHT...WEAK LOW LEVEL FLOW WILL PREVAIL WITH SFC RIDGING
FROM SASK/MANITOBA THROUGH THE NRN LAKES. WNW 925-850 MB FLOW WITH
850 MB TEMPS AROUND -11C WILL SUPPORT POTENTIAL FOR SOME LIGHT LES.
TUESDAY INTO WEDNESDAY...THE MODELS WERE IN RELATIVELY GOOD
AGREEMENT WITH THE EVOLUTION OF THE WINTER STORM EMERGING FROM THE
PLAINS WITH LITTLE CHANGE FROM PREVIOUS FCSTS. ALTHOUGH THE GFS
REMAINED A BIT FARTHER N WITH THE PATH...OVERALL DIFFERENCES
COMPARED TO THE ECMWF/GEM OR DEPARTURE FROM GFS ENSEMBLE MEAN WAS
RELATIVELY MINOR. HOWEVER...THE MODELS HAVE TRENDED SLIGHTLY FASTER
WITH THE SYSTEM.
AS THE MID LEVEL LOW LIFTS OUT OF THE PLAINS STRONG 700-300 MB
QVECTOR CONV AND 290K-300K ISENTROPIC LIFT WILL SUPPORT A PERIOD OF
HEAVY SNOW...ESPECIALLY FROM 21Z/02-06Z/03. QPF AMOUNTS IN THE 0.4
TO 0.7 INCH RANGE ARE CONSISTENT WITH THE DECENT MOISTURE TRANSPORT
AND 3 G/KG AVAILABLE. EVEN WITH THE STRONGEST LIFT ABOVE THE
DGZ...SLR VALUES IN THE 15/1-20/1 RANGE ARE EXPECTED LEADING TO 12-
18 HOUR SNOWFALL AMOUNTS OF 8 TO 10 INCHES OVER MUCH OF THE CNTRL
CWA...WITH THE HEAVIEST AMOUNTS OVER THE S AND E. SINCE THE WRN CWA
FROM IWD TO CMX WILL BE ON THE WRN SIDE OF THE LARGE SYNOPTIC PCPN
AREA...CONFIDENCE IN REACHING WARNING AMOUNTS WAS LOWER.
ACCORDINGLY...THE POTENTIAL FOR LAKE ENHANCEMENT OVER THE WEST IS
ALSO LOWER...ESPECIALLY DURING THE PORTION OF THE EVENT WITH NE LOW
LEVEL FLOW. SO...THE WINTER STORM WATCH WAS ISSUED FOR BARAGA/IRON
COUNTIES EASTWARD. LAKE AND UPSLOPE FLOW ENHANCEMENT WILL BE LIKELY
INTO N CNTRL UPPER MI AS 850 MB TEMPS FALL TO AROUND -10C BY 06Z/WED
WITH INCREASING NNE WINDS. SNOW TOTALS MAY EXCEED 12 INCHES IN THE
HIGHER TERRAIN WEST OF MARQUETTE. THE HEAVIER SNOW IS EXPECTED TO END
OVER THE SOUTH BY 12Z AND IN THE NORTH BY AFTERNOON AS THE SYNOPTIC
MOISTURE/LIFT DEPART BUT WITH THE WINDS...DRIVING WILL STILL BE
DIFFICULT.
ALTHOUGH THE FCST WINDS ARE NOT EXTREMELY STRONG AND SLIGHTLY LOWER
THAN PRREVIOUS FCSTS...CONSIDERABLE BLSN IS EXPECTED NEAR LAKE
SUPERIOR AND S CNTRL FROM ESC-MNM.
THU-SUN...A FEW CLIPPER SHORTWAVE TROUGHS ARE EXPECTED TO MOVE
THROUGH THE NRN LAKES THAT COULD BRING SOME LIGHT SNOW TO THE CWA.
THERE IS LOW CONFIDENCE IN TIMING/POSITION OF THESE FEATURES AND
IMPACT ON LES. COLD ENOUGH AIR WILL PREVAIL FOR PERIODS OF LES FOR
MAINLY NW FLOW FAVORED LOCATIONS. THE GFS WAS MORE AGGRESSIVE IN
BRINING COLD AIR INTO THE NRN LAKES BY NEXT WEEKEND COMPARED TO THE
ECMWF.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 657 PM EST SUN JAN 31 2016
IFR DECK HAS SNUCK INTO KCMX QUICKLY THIS EVENING. EXPECT THIS DECK
TO POSSIBLY LIFT TO 010-015 MVFR BUT IT SHOULD STAY OVERHEAD IN SOME
SHAPE OR FORM INTO MON WITH NW WINDS AND WEAK COLD AIR ADVECTION.
SMALL POTENTIAL FOR ANY SNOW/FZDZ...BUT SEEMS THAT BEST CHANCES WILL
BE LATE TONIGHT INTO MON WITH ARRIVAL OF SLIGHTLY COLDER TEMPS ALOFT.
AT IWD AND SAW...CONDITIONS ARE VFR WITH MID-HIGH CLOUDS LINGERING
AT SAW. EXPECT LOW CLOUD DECK...POSSIBLY DOWN TO IFR TO FORM AT IWD
AROUND MIDNIGHT. WILL KEEP IT 010 THROUGH REST OF NIGHT UNTIL TRENDS
ARE BETTER KNOWN. AT SAW...GRADUALLY SHOULD SEE MVFR DECK FORM BUT
IT MAY TAKE UNTIL WELL AFT MIDNIGHT. WILD CARD AT IWD AND SAW IS
POSSIBLE RADIATION FOG/STRATUS FORMING AHEAD OF SCHEDULE THIS
EVENING. IF THIS OCCURS...VSBY COULD TANK AS IT DID LAST NIGHT AT
IWD. EXPECT 010-020 MVFR TO PERSIST INTO MON THOUGH CIGS MAY BUMP UP
TO 020-030 AS THE DAY PROGRESSES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 306 PM EST SUN JAN 31 2016
ATTENTION DURING THIS FCST PERIOD WILL BE FOCUSED ON THE MIDWEEK
PORTION OF THE FCST AS LOW PRES TRACKS FROM THE SRN PLAINS NE ACROSS
THE GREAT LAKES. LOOKS LIKE THE LOW WILL GENERATE A PERIOD OF NE TO
N GALES LATE TUE NIGHT THRU EARLY WED AFTN OVER ALL BUT FAR WRN LAKE
SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY
AFTERNOON FOR MIZ004>007-010>014-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...VOSS
LONG TERM...JLB
AVIATION...JLA
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
702 PM EST SUN JAN 31 2016
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 306 PM EST SUN JAN 31 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW ACROSS THE
CONUS. STRONG SRN STREAM SHORTWAVE MOVING ONSHORE OF CA WILL BE THE
FEATURE OF INTEREST FOR A GREAT LAKES WINTER STORM MID WEEK AS IT
TRACKS E...THEN NE. SHORTWAVE OF INTEREST IN SHORT TERM IS NOW
MOVING E ACROSS NORTHERN IOWA. SOME LIGHT PCPN HAS DEVELOPED ACROSS
ERN IA AND MAINLY THE SE HALF OF WI THIS AFTERNOON WITH THIS
FEATURE...AIDED BY UPR DIVERGENCE IN RIGHT ENTRANCE OF UPPER JET NOW
MOVING INTO SRN QUEBEC.
SHORTWAVE OVER IA WILL CONTINUE TO AMPLIFY AS IT MOVES INTO THE WRN
GREAT LAKES THIS EVENING. IN TURN...ASSOC SFC WILL TRACK FROM SRN
LAKE MI TO NEAR THE GEORGIAN BAY THIS EVENING. DEEP LAYER FORCING
SPREADING INTO THE AREA IN ASSOCIATION WITH APPROACHING AMPLIFYING
SHORTWAVE PER MID-LVL Q-VECT CONV AND 700-600 MB FGEN HAS HELPED
SUPPORT SOME LIGHT RAIN OVER SCNTRL AND SE CWA THIS AFTERNOON AS
NOTED ON AREA WEBCAMS.
BASED ON FCST SOUNDINGS AND 1000-850MB THICKNESS FIELD...ANY PCPN
OVER THE SE FCST AREA SHOULD TURN FROM RAIN OR RAIN/SNOW MIX TO
MOSTLY SNOW BY THIS EVENING AS LOW-LEVELS FINALLY BEGIN TO COOL. NOT
EXPECTING MUCH IF ANY SNOW ACCUMULATION (A FEW TENTHS) DUE TO MIX OF
PCPN AND ABOVE FREEZING SFC TEMPS THIS AFTERNOON...EVEN IF PCPN
CHANGES TO ALL SNOW.
TONIGHT...SHORTWAVE FROM NEAR IA MOVES THROUGH THE UPPER GREAT LAKES
WHILE A SFC TROF DROPS S ACROSS LAKE SUPERIOR AND INTO MOST OF NRN
UPPER MI BY 12Z MON. FCST SOUNDINGS SUGGEST MOISTURE DEPTH MAY NOT
BE SUFFICIENT TO REACH SUB -10C TEMPS CONSISTENTLY...ESPECIALLY IN
THE EVENING. SO THERE IS SOME POTENTIAL FOR -FZDZ AT THAT TIME IF
PCPN OCCURS. THE GENERAL LACK OF SYNOPTIC FORCING AND MARGINAL AT
BEST INSTABILITY OVER THE LAKE SUGGESTS NOTHING MORE THAN 20-30 PCT
POPS FOR -SN/-FZDZ ARE WARRANTED NEAR LAKE SUPERIOR TONIGHT. EXPECT
MIN TEMPS IN THE LOWER TO MID 20S.
MONDAY...WEAK WINDS AND SHEAR WITHIN CONVECTIVE BOUNDARY LAYER ALONG
WITH MARGINAL INSTABILITY WILL AGAIN LIMIT POPS TO GENERALLY NO MORE
THAN 30 PCT FOR WNW SNOWBELTS. MAX TEMPS WILL RANGE FROM THE MID TO
UPPER 20S NORTH TO LOWER 30S SOUTH CENTRAL UNDER MOSTLY CLOUDY
SKIES.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 514 PM EST SUN JAN 31 2016
A BROAD MID/UPPER LEVEL TROUGH OVER THE WEST INTO CNTRL CONUS WILL
GIVE WAY TO RIDGING OVER WRN NOAM RESULTING IN NW FLOW INTO THE NRN
LAKES AND INTRUSIONS OF ARCTIC AIR INTO OR JUST TO THE NE OF THE
REGION. THE MAIN WEATHER STORY WILL BE THE WINTER STORM MOVING OUT
OF THE PLAINS INTO THE GREAT LAKES TUE INTO WED.
MONDAY NIGHT...WEAK LOW LEVEL FLOW WILL PREVAIL WITH SFC RIDGING
FROM SASK/MANITOBA THROUGH THE NRN LAKES. WNW 925-850 MB FLOW WITH
850 MB TEMPS AROUND -11C WILL SUPPORT POTENTIAL FOR SOME LIGHT LES.
TUESDAY INTO WEDNESDAY...THE MODELS WERE IN RELATIVELY GOOD
AGREEMENT WITH THE EVOLUTION OF THE WINTER STORM EMERGING FROM THE
PLAINS WITH LITTLE CHANGE FROM PREVIOUS FCSTS. ALTHOUGH THE GFS
REMAINED A BIT FARTHER N WITH THE PATH...OVERALL DIFFERENCES
COMPARED TO THE ECMWF/GEM OR DEPARTURE FROM GFS ENSEMBLE MEAN WAS
RELATIVELY MINOR. HOWEVER...THE MODELS HAVE TRENDED SLIGHTLY FASTER
WITH THE SYSTEM.
AS THE MID LEVEL LOW LIFTS OUT OF THE PLAINS STRONG 700-300 MB
QVECTOR CONV AND 290K-300K ISENTROPIC LIFT WILL SUPPORT A PERIOD OF
HEAVY SNOW...ESPECIALLY FROM 21Z/02-06Z/03. QPF AMOUNTS IN THE 0.4
TO 0.7 INCH RANGE ARE CONSISTENT WITH THE DECENT MOISTURE TRANSPORT
AND 3 G/KG AVAILABLE. EVEN WITH THE STRONGEST LIFT ABOVE THE
DGZ...SLR VALUES IN THE 15/1-20/1 RANGE ARE EXPECTED LEADING TO 12-
18 HOUR SNOWFALL AMOUNTS OF 8 TO 10 INCHES OVER MUCH OF THE CNTRL
CWA...WITH THE HEAVIEST AMOUNTS OVER THE S AND E. SINCE THE WRN CWA
FROM IWD TO CMX WILL BE ON THE WRN SIDE OF THE LARGE SYNOPTIC PCPN
AREA...CONFIDENCE IN REACHING WARNING AMOUNTS WAS LOWER.
ACCORDINGLY...THE POTENTIAL FOR LAKE ENHANCEMENT OVER THE WEST IS
ALSO LOWER...ESPECIALLY DURING THE PORTION OF THE EVENT WITH NE LOW
LEVEL FLOW. SO...THE WINTER STORM WATCH WAS ISSUED FOR BARAGA/IRON
COUNTIES EASTWARD. LAKE AND UPSLOPE FLOW ENHANCEMENT WILL BE LIKELY
INTO N CNTRL UPPER MI AS 850 MB TEMPS FALL TO AROUND -10C BY 06Z/WED
WITH INCREASING NNE WINDS. SNOW TOTALS MAY EXCEED 12 INCHES IN THE
HIGHER TERRAIN WEST OF MARQUETTE. THE HEAVIER SNOW IS EXPECTED TO END
OVER THE SOUTH BY 12Z AND IN THE NORTH BY AFTERNOON AS THE SYNOPTIC
MOISTURE/LIFT DEPART BUT WITH THE WINDS...DRIVING WILL STILL BE
DIFFICULT.
ALTHOUGH THE FCST WINDS ARE NOT EXTREMELY STRONG AND SLIGHTLY LOWER
THAN PRREVIOUS FCSTS...CONSIDERABLE BLSN IS EXPECTED NEAR LAKE
SUPERIOR AND S CNTRL FROM ESC-MNM.
THU-SUN...A FEW CLIPPER SHORTWAVE TROUGHS ARE EXPECTED TO MOVE
THROUGH THE NRN LAKES THAT COULD BRING SOME LIGHT SNOW TO THE CWA.
THERE IS LOW CONFIDENCE IN TIMING/POSITION OF THESE FEATURES AND
IMPACT ON LES. COLD ENOUGH AIR WILL PREVAIL FOR PERIODS OF LES FOR
MAINLY NW FLOW FAVORED LOCATIONS. THE GFS WAS MORE AGGRESSIVE IN
BRINING COLD AIR INTO THE NRN LAKES BY NEXT WEEKEND COMPARED TO THE
ECMWF.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 657 PM EST SUN JAN 31 2016
IFR DECK HAS SNUCK INTO KCMX QUICKLY THIS EVENING. EXPECT THIS DECK
TO POSSIBLY LIFT TO 010-015 MVFR BUT IT SHOULD STAY OVERHEAD IN SOME
SHAPE OR FORM INTO MON WITH NW WINDS AND WEAK COLD AIR ADVECTION.
SMALL POTENTIAL FOR ANY SNOW/FZDZ...BUT SEEMS THAT BEST CHANCES WILL
BE LATE TONIGHT INTO MON WITH ARRIVAL OF SLIGHTLY COLDER TEMPS ALOFT.
AT IWD AND SAW...CONDITIONS ARE VFR WITH MID-HIGH CLOUDS LINGERING
AT SAW. EXPECT LOW CLOUD DECK...POSSIBLY DOWN TO IFR TO FORM AT IWD
AROUND MIDNIGHT. WILL KEEP IT 010 THROUGH REST OF NIGHT UNTIL TRENDS
ARE BETTER KNOWN. AT SAW...GRADUALLY SHOULD SEE MVFR DECK FORM BUT
IT MAY TAKE UNTIL WELL AFT MIDNIGHT. WILD CARD AT IWD AND SAW IS
POSSIBLE RADIATION FOG/STRATUS FORMING AHEAD OF SCHEDULE THIS
EVENING. IF THIS OCCURS...VSBY COULD TANK AS IT DID LAST NIGHT AT
IWD. EXPECT 010-020 MVFR TO PERSIST INTO MON THOUGH CIGS MAY BUMP UP
TO 020-030 AS THE DAY PROGRESSES. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 306 PM EST SUN JAN 31 2016
ATTENTION DURING THIS FCST PERIOD WILL BE FOCUSED ON THE MIDWEEK
PORTION OF THE FCST AS LOW PRES TRACKS FROM THE SRN PLAINS NE ACROSS
THE GREAT LAKES. LOOKS LIKE THE LOW WILL GENERATE A PERIOD OF NE TO
N GALES LATE TUE NIGHT THRU EARLY WED AFTN OVER ALL BUT FAR WRN LAKE
SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY
AFTERNOON FOR MIZ004>007-010>014-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLB
AVIATION...JLA
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
646 PM EST SUN JAN 31 2016
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 329 PM EST SUN JAN 31 2016
LOW PRESSURE WILL MOVE EAST OF LOWER MICHIGAN THIS EVENING WITH
PRECIPITATION ENDING FROM WEST TO EAST. FAIR WEATHER WILL FOLLOW FOR
MONDAY INTO EARLY TUESDAY...THEN ANOTHER STORM WILL BRING RAIN AND
SNOW FOR TUESDAY AND TUESDAY NIGHT. COLDER WEATHER WITH OCCASIONAL
SNOW SHOWERS CAN BE EXPECTED FOR THE LATTER HALF OF THE WEEK.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 329 PM EST SUN JAN 31 2016
THE STORM TRACK ON TUESDAY AND TUESDAY NIGHT HAS TRENDED A LITTLE
FURTHER NORTH WITH THE LATEST MODEL GUIDANCE AND THIS WAS FOLLOWED
IN THE FORECAST UPDATE TO TREND TO SLIGHTLY LOWER SNOWFALL
AMOUNTS ACROSS THE NORTHERN FORECAST ZONES.
FOR TONIGHT...BACK EDGE OF PRECIP FROM THE CURRENT LOW TRACKING
ACROSS LOWER MICHIGAN SHOULD BE CLEARING THE EASTERN ZONES BY
MIDNIGHT. THERE SHOULD BE SOME SNOW MIXING IN UP NORTH BEFORE IT
ENDS BUT MARGINAL AIR AND SKIN TEMPS SHOULD PREVENT ANY ACCUMS.
QUIET WEATHER FOR MONDAY INTO EARLY TUESDAY BEFORE THE NEXT LOW
EJECTING FROM THE WESTERN LONGWAVE TROUGH ARRIVES. EAST WINDS
SHOULD HOLD ENOUGH COLD AIR IN FOR SOME MIXED PRECIP AT THE START
BUT SFC TEMPS LOOK MARGINAL FOR ANY ICING. DESPITE STRONG
EASTERLY FLOW THE COLD AIR ADVECTION IS RELATIVELY WEAK COMPARED
TO THE 28 DECEMBER STORM...WHICH WAS ABLE TO MAINTAIN SLEET AND
SOME FREEZING RAIN FOR SEVERAL HOURS.
WE WILL CONTINUE TO MONITOR ICING POTENTIAL BUT AT THIS POINT IT
APPEARS SKIN TEMPS WILL BE MARGINAL AND CAA NOT STRONG ENOUGH TO
ACCOUNT FOR MUCH. SNOW SHOULD BE CONFINED TO THE NORTHERN TIER AND
THE HIGHER ELEVATIONS COULD GET 2 TO 4 INCHES.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 329 PM EST SUN JAN 31 2016
FAIRLY UNEVENTFUL FOR MUCH OF THE LONG TERM...HOWEVER A CLIPPER
SYSTEM SHOULD GIVE US SNOW FRIDAY NIGHT AND SATURDAY.
MOISTURE BEHIND THE SYSTEM QUICKLY BECOMES SHALLOW...SO ITS
QUESTIONABLE HOW MUCH LAKE EFFECT WE SEE INITIALLY AS THE DGZ DOES
NOT APPEAR TO BE SATURATED. WILL LOWER POPS A BIT FOR WED WHERE WE
STILL MAY SEE SOME RAIN EARLY IN THE MORNING...GRADUALLY TRANSITING
TO LIGHT LAKE EFFECT SNOW INTO THE AFTERNOON. WEAK SURFACE RIDGING
SHOULD DEVELOP LATE WED NIGHT INTO THURSDAY...DIMINISHING ANY LAKE
EFFECT SNOWS.
LAKE EFFECT STILL LOOKS MORE MINIMAL THAN PREVIOUS RUNS RIGHT INTO
EARLY FRIDAY AS THE SURFACE RIDGE ONLY SLOWLY MOVES EAST. WILL KEEP
POPS IN...BUT WE MAY HAVE TO TRIMMED THEM BACK IF THESE MODEL TRENDS
CONTINUE. THE FLOW LOOKS TO BECOME MORE FAVORABLE FOR LAKE EFFECT
AS WE GET INTO LATE FRIDAY AS A CLIPPER SYSTEM APPROACHES. SW FLOW
LAKE ENHANCEMENT SHOULD KICK IN FRIDAY AFTERNOON OR EVENING.
THE MODELS ARE IN GOOD AGREEMENT SHOWING THE CLIPPER/S SURFACE LOW
STAYING WELL NORTH...OVER THE SUPERIOR REGION. IT DRAGS A FRONT
THROUGH SW MI SATURDAY MORNING WHEN THE SNOW ENHANCEMENT SHOULD
PEAK. ANOTHER SURGE OF COLDER AIR MOVES IN BEHIND THE CLIPPER BY
SATURDAY NIGHT/SUNDAY WHICH SHOULD HELP MAINTAIN LIGHT LAKE EFFECT
SNOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 646 PM EST SUN JAN 31 2016
THE SYSTEM THAT BOUGHT LIFR CIGS/VSBY AND LIGHT RAIN TO THE AREA
IS EXITING THE AREA AS I WRITE THIS. THE RAIN SHOULD BE OUT OF THE
AREA BY 03Z OR SO. I WOULD EXPECT CIGS TO BECOME MVFR BY 04Z TO
06Z ACROSS THE AREA. HOWEVER....FOR THE MKG AND GRR TAF SITES...
WINDS BECOME RATHER LIGHT TOWARD MORNING... AND GIVEN THIS IS NOT
THAT STRONG OF A COLD FRONT IN THE FIRST PLACE... THE RAP AND
HRRR ARE BOTH SHOWING DENSE FOG ACROSS MOST OF THE AREA NORTH OF
I-94 AND FROM AROUND GRAND RAPIDS TO THE LAKE SHORE. I DID PUT
THIS IN THE TAFS AS WINDS DO GO LIGHT AND THERE IS STILL MELTING
SNOW. BEYOND THAT ANY FOG SHOULD LIFT BY MID MORNING LEAVING MVFR
CIGS ACROSS THE AREA.
&&
.MARINE...
ISSUED AT 329 PM EST SUN JAN 31 2016
WINDS AND WAVES WILL BE RELATIVELY LIGHT THROUGH MONDAY BUT THERE
WILL BE SOME AREAS OF DENSE FOG AT TIMES TONIGHT.
&&
.HYDROLOGY...
ISSUED AT 1245 PM EST SUN JAN 31 2016
MINOR FLOODING IS POSSIBLE LATER THIS WEEK... ESPECIALLY IN
LOWLAND AREAS NEAR RIVERS. SOME RIVERS MAY EXCEED BANKFULL DUE TO
SNOW MELT AND A STORM TUESDAY INTO WEDNESDAY. STORM TOTAL
PRECIPITATION OF 0.50-1.00 INCHES IS POSSIBLE. PRECIPITATION IS
STILL EXPECTED TO BE A WINTRY MIX OR PLAIN RAIN. RIVER LEVEL RISES
ARE ESPECIALLY LIKELY FROM MIDWEEK THROUGH NEXT WEEKEND.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...JK
AVIATION...WDM
HYDROLOGY...EBW
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
416 PM EST SAT JAN 30 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 346 PM EST SAT JAN 30 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A MAINLY ZONAL MID/UPPER LEVEL
PATTERN ACROSS THE CONUS. A WEAK UPSTREAM SHORTAVE TROUGH WAS MOVING
INTO THE NRN PLAINS. AT THE SFC...A 984 MB LOW WAS MOVING THROUGH
NRN ONTARIO TOWAD JAMES BAY RESULTING IN SW TO W FLOW OR MILD
PACIFIC AIR INTO THE REGION. TEMPS HAVE CLIMBED TO NEAR OR ABOVE
RECORD VALUES WITH 44F AT THE NWS OFFICE BREAKING THE OLD RECORD OF
41. VIS LOOP SHOWED MOSTLY CLEAR SKIES OVER MOST OF UPPER MI WITH
MID/HIGH CLOUDS GRADUALLY SPREADING INTO THE SOUTH.
TONIGHT INTO SUN...MILD CONDITIONS WILL PREVAIL AS A WEAK TROUGH
INTO CNTRL MN MOVES INTO THE REGION. A BAND OF 800-600 MB FGEN
ASSOCIATED WITH A JET STREAK LIFTING NE FROM THE NRN LAKES WILL HELP
SUPPORT AN AREA OF PCPN FROM CNTRL INTO NE WI AND INTO FAR SRN AND
POSSIBLY SE UPPER MI. MODELS CONSENSUS SUGGESTS THAT QPF AMOUNTS TO
AROUND 0.10 INCH FROM 06Z-18Z MAY AFFECT LOCATIONS NEAR MNM.
HOWEVER...GIVEN THE MODELS SPREAD...CONFIDENCE IS MARGINAL AND MAINLY
CHNANCE POPS WERE MENTIONED EXCEPT AT MNM (60 POP) AROUND 12Z. LOW
LEVEL TEMP PROFILES SUPPORT MAINLY RAIN AS THE PCPN TYPE.
HOWEVER...WITH TEMPS FALLING TO NEAR 32F A BIT FARTHER INLAND...SOME
FZRA/SN MAY ALSO MIX WITH THE PCPN. SO...EVEN THOUGH LITTLE OR NO
ICE/SNOW ACCUMULATIONS ARE EXPECTED ANY SMALL AMOUNTS ON UNTREATED
SURFACES COULD STILL CREATE HAZARDOUS CONDITIONS. AS THE DEEPER
MOISTURE MOVES OUT IN THE MORNING...AND LOW LEVEL MOISTURE LINGERS
ALONG THE TROUGH/FRONT...SOME DZ/FZDZ WILL BE POSSIBLE OVER THE SE
HALF. TEMPS WILL REMAIN WELL ABOVE NORMAL WITH HIGHS FROM THE LOWER
30S OVER THE NW HALF TO THE MID AND UPPER 30S OVER THE S AND E.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 415 PM EST SAT JAN 30 2016
...WINTER STORM LATE TUESDAY INTO WEDNESDAY IS STILL ON...
SPLIT FLOW PATTERN ALOFT HAS RE-ORGANIZED THE LAST DAY WITH STRONG
JET ACROSS PACIFIC SPLITTING ALONG WEST COAST. STRONGEST JET ENERGY
IS IN SOUTHERN STREAM AS IT MERGES WITH SUBTROPICAL JET ALONG SE
CONUS COAST. NORTHERN BRANCH JET IS WEST-EAST ACROSS NORTHERN PLAINS
AND GREAT LAKES. EXPECTATION IS THAT INTO EARLY THIS WEEK...JET
CRASHING INTO WEST COAST WILL DIG INTO SOUTHERN CA/BAJA CA WHILE
CARVING A TROUGH OUT OVER SW CONUS. AS THIS IS OCCURRING...TWO MAIN
PIECES OF SHORTWAVE ENERGY...CURRENTLY OFFSHORE OF BRITISH COLUMBIA
WITH THE OTHER WELL TO WEST OF CA WILL PHASE TOGETHER WITHIN THIS
MEAN TROUGH. PHASING WOULD APPEAR TO BE DONE BY MON MORNING...SO
THEN IT JUST BECOMES A TRACK FORECAST OF THE SHORTWAVE TROUGH AND
ASSOCIATED SFC LOW. LATEST GUIDANCE STILL IN GOOD AGREEMENT ON SFC
LOW MOVING TO NORTHERN LOWER/EASTERN UPR MICHIGAN BY WED MORNING.
UPSHOT IS THAT STRONG STORM WITH SNOW/WIND REMAINS ON TRACK FOR UPR
MICHIGAN TUE NIGHT INTO WED.
BACK OVER UPR LAKES IT LOOKS PRETTY QUIET IN THE LEAD UP TIME TO THE
POTENTIAL STORM. NORTHERN STREAM FLOW REMAINS ACROSS GREAT LAKES
EARLY IN THE WEEK. STRONG SFC LOW MOVING BY OVER ONTARIO AND QUEBEC
THIS AFTN WILL LEAD A SFC TROUGH/COLD FRONT TO ITS WEST. BY LATE SUN
THIS FRONT SHOULD STILL BE NORTH OF UPR MICHIGAN/LK SUPERIOR THOUGH
LEAD TROUGH MAY BE THROUGH UPR MICHIGAN BY THAT TIME. LEAD WAVE IN
THE NORTHERN STREAM WORKS THROUGH ON SUN NIGHT WITH WEAK LARGE SCALE
LIFT. MAIN AFFECT OF THE WAVE WILL BE TO BRING H85 COLD FRONT OVER
UPR MICHIGAN ALONG WITH INCREASING H9-H8 MOISTURE AND PUSH SFC COLD
FRONT OVER LK SUPERIOR. ONSHORE FLOW AND TEMPS AT TOP OF INVERSION
MARGINALLY COLD FOR LAKE EFFECT /MAYBE LOWER THAN -10C/ SHOULD LEAD
TO LIGHT LAKE EFFECT PRECIPITATION SUN NIGHT INTO MON FOR NW-N FLOW
AREAS. WITH GOOD PART OF THIS TIME FEATURING TEMPS -8C OR WARMER
ALSO PUT MENTION OF FZDZ IN THE GRIDS. PROBABLY LOOKING AT FLURRIES
AND FZDZ SUN NIGHT THEN BETTER SHOT AT SNOW SHOWERS MON AS IT TURNS
SLIGHTLY COOLER AT H85. BEST CHANCE OF MUCH PRECIP THROUGHOUT WILL
BE OVER NW INTO NCNTRL CWA WITH UPSLOPE NW FLOW. OVERALL NOT LOOKING
AT MUCH SNOW WITH LIMITED CONVERGENCE AND MINIMAL COLD AIR. HINT
THAT ANOTHER WEAK WAVE WORKS THROUGH LATE MON INTO MON EVENING WITH
MORE OF WIDESPREAD LGT SNOW/FLURRIES. WARM AIR ADVECTION COULD LEAD
TO MORE FZDZ LATER AT NIGHT AS DEEPER MOISTURE/FORCING ARE REMOVED.
ATTN TUE MORNING WILL BE ON THE WINTER STORM ONGOING OVER THE HIGH
PLAINS. STEADY MODERATE TO HEAVY SNOW SHOULD BE SPREADING ACROSS
MUCH OF CO/KS/SW NEB AND HEADING TOWARD EASTERN NEB/WESTERN IA. SFC
LOW SHOULD BE VCNTY OF KS/OK BORDER. AS SHRA/TSRA START DEVELOPING
IN THE WARM SECTOR DOWN THE MISSISSIPPI RIVER VALLEY...SNOW WILL BE
EXPANDING AND INCREASING ON TUE AS IT CROSSES FM MID MO RIVER VALLEY
TOWARD WESTERN GREAT LAKES LATE IN THE DAY AS DEEP GULF MOISTURE IS
INGESTED INTO THE SYSTEM. STRONG DEEP LAYER Q-VECTOR CONVERGENCE AND
STRONG UPPER LEVEL DIFFLUENCE AND DIVERGENCE ALOFT IN EXIT REGION OF
150+ KTS JET STREAK OVER SOUTHERN PLAINS SHOULD AID IN WIDESPREAD
HEAVY SNOW DEVELOPING AS IT MOVES INTO THE WESTERN GREAT LAKES.
EXPECT MODERATE SNOW TO REACH SCNTRL UPR MICHIGAN DURING THE AFTN.
FARTHER NORTH...EAST WINDS AND TEMPS IN LOW-LEVEL MOIST LAYER -8C TO-
10C SHOULD ALLOW SNOW TO START TO EXPAND NW/NCNTRL BY LATE DAY
THOUGH INTENSITY SHOULD BE HELD DOWN AS DEEP MOISTURE IS LIMITED
ABOVE 850MB UNTIL RIGHT AT 00Z. WORTH SMALL CHANCE POPS WHILE
SPREAD LIKELY POPS OVER THE SCNTRL IN THE AFTN.
BULK OF STORM OCCURS TUE NIGHT THROUGH MIDDAY WED. AS THE SFC LOW
REACHES NORTHERN LK MICHIGAN/NORTHERN LOWER MICHIGAN BY 12Z WED...
EXPECT WIDESPREAD SNOW OVER ALL OF UPR MICHIGAN. BASED ON TRACK OF
H85-H7 LOWS...HEAVIEST STRIPE OF SNOW WILL BE OVER CNTRL CWA. MOST
AREAS WILL SEE HEAVY SNOW FOR A TIME THOUGH AND WARNING AMOUNTS OF
AT LEAST 6 INCHES/12 HOURS WOULD BE MET. LAKE ENHANCEMENT/UPSLOPE
NORTHEAST WINDS WITH H85 TEMPS DOWN BLO -10C WILL ADD TO SNOW
INTENSITY AND TOTALS FOR NCNTRL CWA. THOUGH BULK OF SYSTEM SNOW
REMAINS TO EAST OF WESTERN CWA...COLDER TEMPS/HIGHER SLR/S AND
FAVORABLE NRLY FLOW WILL RESULT IN SEVERAL INCHES OF SNOW AND
POSSIBLE WARNING AMOUNTS THERE AS WELL. LAST...BUT CERTAINLY NOT
LEAST IS THE NORTH WINDS OVER 20 MPH WITH HIGHER GUSTS THAT WILL
LEAD TO CONSIDERABLE BLOWING SNOW AND REDUCED VSBY. AT LEAST
LOCALIZED BLIZZARD CONDITIONS COULD OCCUR. LAKE ENHANCED SNOW OR AT
LEAST LAKE EFFECT CONTINUES INTO WED AFTN/WED EVENING. SOME SLIGHT
DIFFERENCES IN TRACK OF LOW...WITH ECMWF MORE OVER ALPENA AT 12Z WED
AND GEM OVER CNTRL LK MICHIGAN. THERE WILL STILL BE SOME ADJUSTMENTS
BUT OVERALL FLAVOR OF RECENT FORECASTS WITH THIS STORM ARE STILL ON
TRACK.
BEHIND THIS SYSTEM...MEAN TROUGHING AND COLD AIR WITH H85 TEMPS DOWN
IN THE -15C TO -20C RANGE WILL KEEP LAKE EFFECT GOING FOR NW FLOW
AREAS. RETAINED PREVIOUS SHIFTS HIGHER POPS OVER CONSENSUS. MAY TURN
EVEN COLDER FOR NEXT WEEKEND...SO THE LAKE EFFECT WILL CONTINUE.
AFTER THE MILD BREAK TODAY AND SUNDAY...LOOKS TO REMAIN WINTRY ON
INTO MID FEB.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1253 PM EST SAT JAN 30 2016
W TO SW FLOW OF RELATIVELY DRY PACIFIC AIR WILL MAINTAIN VFR
CONDITIONS THROUGH THIS EVENING. DIURNAL COOLING AND A WEAK TROUGH
MOVING INTO UPPER MICHIGAN IS EXPECTED TO BRING IN LOWER CLOUDS
OVERNIGHT WITH MVFR CIGS AT CMX AND SAW AND IFR AT IWD. SOME VSBY
REDUCTION WITH FOG IS ALSO POSSILBE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 550 AM EST SAT JAN 30 2016
STRONG LOW TRACKING OVER NORTHERN ONTARIO THIS MORNING WILL RESULT
IN SOUTHWEST WINDS 20-30 KTS TODAY. WINDS DIMINISH TONIGHT INTO SUN
AS RIDGING MOVES OVERHEAD. A LOW PRESSURE SYSTEMS TRACKING ACROSS
THE CENTRAL GREAT LAKES WILL LIKELY BRING NORTH TO NORTHEAST GALES
TUE NIGHT INTO WED.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
349 PM EST SAT JAN 30 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 346 PM EST SAT JAN 30 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A MAINLY ZONAL MID/UPPER LEVEL
PATTERN ACROSS THE CONUS. A WEAK UPSTREAM SHORTAVE TROUGH WAS MOVING
INTO THE NRN PLAINS. AT THE SFC...A 984 MB LOW WAS MOVING THROUGH
NRN ONTARIO TOWAD JAMES BAY RESULTING IN SW TO W FLOW OR MILD
PACIFIC AIR INTO THE REGION. TEMPS HAVE CLIMBED TO NEAR OR ABOVE
RECORD VALUES WITH 44F AT THE NWS OFFICE BREAKING THE OLD RECORD OF
41. VIS LOOP SHOWED MOSTLY CLEAR SKIES OVER MOST OF UPPER MI WITH
MID/HIGH CLOUDS GRADUALLY SPREADING INTO THE SOUTH.
TONIGHT INTO SUN...MILD CONDITIONS WILL PREVAIL AS A WEAK TROUGH
INTO CNTRL MN MOVES INTO THE REGION. A BAND OF 800-600 MB FGEN
ASSOCIATED WITH A JET STREAK LIFTING NE FROM THE NRN LAKES WILL HELP
SUPPORT AN AREA OF PCPN FROM CNTRL INTO NE WI AND INTO FAR SRN AND
POSSIBLY SE UPPER MI. MODELS CONSENSUS SUGGESTS THAT QPF AMOUNTS TO
AROUND 0.10 INCH FROM 06Z-18Z MAY AFFECT LOCATIONS NEAR MNM.
HOWEVER...GIVEN THE MODELS SPREAD...CONFIDENCE IS MARGINAL AND MAINLY
CHNANCE POPS WERE MENTIONED EXCEPT AT MNM (60 POP) AROUND 12Z. LOW
LEVEL TEMP PROFILES SUPPORT MAINLY RAIN AS THE PCPN TYPE.
HOWEVER...WITH TEMPS FALLING TO NEAR 32F A BIT FARTHER INLAND...SOME
FZRA/SN MAY ALSO MIX WITH THE PCPN. SO...EVEN THOUGH LITTLE OR NO
ICE/SNOW ACCUMULATIONS ARE EXPECTED ANY SMALL AMOUNTS ON UNTREATED
SURFACES COULD STILL CREATE HAZARDOUS CONDITIONS. AS THE DEEPER
MOISTURE MOVES OUT IN THE MORNING...AND LOW LEVEL MOISTURE LINGERS
ALONG THE TROUGH/FRONT...SOME DZ/FZDZ WILL BE POSSIBLE OVER THE SE
HALF. TEMPS WILL REMAIN WELL ABOVE NORMAL WITH HIGHS FROM THE LOWER
30S OVER THE NW HALF TO THE MID AND UPPER 30S OVER THE S AND E.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 550 AM EST SAT JAN 30 2016
AN ACTIVE 7 DAY PERIOD IS SHAPING UP. THE CURRENT CHANGE TO A MORE
ZONALLY ORIENTED FLOW ACROSS THE CONUS WILL TRANSITION NEXT WEEK TO
A MORE AMPLIFIED RIDGE IN THE VCNTY OF THE W COAST OF N AMERICA AND
A CORRESPONDING DOWNSTREAM TROF OVER CNTRL AND ERN N AMERICA. AS
THIS OCCURS...VIGOROUS SRN STREAM ENERGY WILL MOVE ACROSS THE SW
STATES EARLY NEXT WEEK BEFORE LIFTING NE INTO THE GREAT LAKES
MIDWEEK ON THE FRONT SIDE OF THE DEVELOPING CNTRL/ERN NAMERICA TROF.
OVER THE LAST 24HRS...THE OVERALL MODEL TREND FROM THE
GFS/CANADIAN/ECMWF/UKMET IS TO OPEN UP THE MID LEVEL ENERGY AS IT
MOVES INTO THE GREAT LAKES. AS A RESULT...THE ASSOCIATED SFC LOW
TRACK TRENDED FARTHER E IN RESPONSE TO THE WEAKENING ENERGY ALOFT.
00Z GFS/ECMWF HAVE REVERSED THAT TREND. MORE ON THIS LATER. PRIOR TO
THE MID WEEK SYSTEM...THERE WAS SOME GROWING CONCERN FOR A POTENTIAL
HEADLINE SNOW EVENT LATER SUN INTO EARLY MON PER NAM/GFS DUE TO
POSSIBLE INTERACTION OF A COUPLE OF SHORTWAVES LEADING TO A
DEEPENING SYSTEM MOVING THRU THE WRN GREAT LAKES. THE NAM WAS
ESPECIALLY STRONG...SHOWING WIDESPREAD SIGNIFICANT SNOW ACROSS MOST
OF THE FCST AREA FOR SEVERAL RUNS. WITH THE 00Z RUNS...THE GFS/NAM
HAVE BOTH TRENDED TOWARD THE FLATTER/WEAKER NON NCEP MODELS. THE
CHANGE IN THE NAM IS VERY DRAMATIC...FOR INSTANCE GOING FROM 1 INCH
OF QPF IN NCNTRL UPPER MI TO JUST A FEW HUNDREDTHS WITH THE 00Z
RUN...AN EPIC FAIL FOR THE NAM. AS FOR TEMPS...TEMPS WILL BE WELL
ABOVE NORMAL THRU SUN...ESPECIALLY TODAY...DUE TO MILD PACIFIC AIR
BEING DRIVEN EASTWARD IN THE BRIEF/TEMPORARY SHIFT TO MORE ZONALLY
ORIENTED FLOW. TEMPS WILL THEN SLOWLY TREND DOWN NEXT WEEK TO AT
LEAST A LITTLE BLO NORMAL IN THE WAKE OF THE MID WEEK STORM. LOOKING
FARTHER AHEAD...CANADIAN ENSEMBLES/NAEFS HAVE CONTINUED THE RECENT
TREND TOWARD A COLDER WEATHER PATTERN THRU THE 2ND WEEK OF FEB. WITH
A STRENGTHENING WRN RIDGE/ERN TROF PATTERN...WOULDN`T BE SURPRISED
TO SEE AN ARCTIC AIR MASS DIVE INTO THE UPPER LAKES THAT WILL BE AS
COLD OR COLDER THAN WE`VE SEEN SO FAR DURING THIS OVERALL MILD
WINTER SEASON. OF COURSE...WITH A BLO NORMAL TEMP REGIME SETTING
UP...LAKE EFFECT SNOW WILL BE VERY ACTIVE LATE IN THE UPCOMING WEEK
THRU THE 2ND WEEK OF FEB.
BEGINNING SUN/SUN NIGHT...AS MENTIONED ABOVE...THERE HAS BEEN A
DRAMATIC SHIFT OF THE GFS/NAM TOWARD THE FLATTER/WEAKER NON NCEP
MODEL GUIDANCE WHICH ONLY TRENDED SLIGHTLY STRONGER OVER THE LAST
24HRS WITH RESPECT TO THE SHORTWAVE ENERGY MOVING THRU THE WRN GREAT
LAKES. AS A RESULT...MODEL AGREEMENT IS NOW QUITE GOOD. IT APPEARS
THAT PCPN DEVELOPMENT ASSOCIATED WITH A SHORTWAVE MOVING THRU THE
WRN GREAT LAKES WILL LARGELY PASS S AND E OF THE FCST AREA AS
FORCING FROM RIGHT ENTRANCE OF UPPER JET AND LOW-MID LEVEL FGEN PASS
S AND E OF HERE. WILL MAINTAIN SOME CHC POPS OVER THE FAR SCNTRL/ERN
FCST AREA FOR SUN/SUN EVENING...BUT THAT MAY BE GENEROUS. PER FCST
SOUNDINGS...PTYPE IN THAT AREA MAY BE A MIX OF -SN/-FZRA/-RA SUN.
ELSEWHERE...THERE MAY NOT BE ANY PCPN TO SPEAK OF SUN/SUN NIGHT.
HOWEVER...INCLUDED SCHC POPS NEAR LAKE SUPERIOR AS UPSLOPE FLOW MAY
HELP GENERATE SOME FLURRIES/-SHSN AS 850MB TEMPS SLOWLY FALL TO THE
MARGINAL THRESHOLD FOR LES. NOT OUT OF THE QUESTION THAT THERE COULD
BE SOME ISSUES WITH -FZDZ IF THE NAM IS CORRECT WITH SHALLOW
SATURATED SFC BASED LAYER THAT HAS TEMPS AOA -10C.
WITH 850MB TEMPS FALLING SLIGHTLY MORE MON/MON NIGHT...MIGHT SEE AN
INCREASE IN LIGHT LES/FLURRIES OFF LAKE SUPERIOR AS WINDS VEER
SLOWLY FROM NW TO A MORE NORTHERLY DIRECTION.
ATTENTION THEN TURNS TO THE LONG ADVERTISED POTENTIAL WINTER STORM
FOR MIDWEEK. AS MENTIONED ABOVE...AFTER AN OVERALL MEDIUM RANGE
MODEL TREND FOR A SFC LOW TRACK SHIFTED SLIGHTLY SE...TODAYS 00Z
GFS/ECMWF HAVE SHIFTED NOTABLY LEFT/W WITH THE TRACK...BACK TO WHAT
WAS CONSIDERED THE CONSENSUS TRACK ON THU...RUNNING FROM THE SRN
PLAINS NE ACROSS NRN LWR MI. ACTUALLY...THE 00Z ECMWF/GFS TRACK IS A
EVEN A BIT FARTHER LEFT/W OF THE THU CONSENSUS TRACK AS THEY TAKE
THE LOW ACROSS NRN LAKE MI INTO FAR ERN UPPER MI. THE CANADIAN IS
STILL FARTHER SE AND HAS MOST OF THE SYNOPTIC PCPN PASSING SE OF THE
FCST AREA. THERE ARE A NUMBER OF CANADIAN ENSEMBLES SUPPORTING A
TRACK ACROSS NRN LWR MI...EVEN A COUPLE THAT TAKE THE LOW EVEN
FARTHER W THRU CNTRL UPPER MI IN ADDITION TO SEVERAL FARTHER SE
TRACKS. THE GFS ENSEMBLES HAVE A SIMILAR SPREAD THOUGH OVERALL
SLIGHTLY NW OF THE CANADIAN ENSEMBLES. AT THIS POINT...WILL CONTINUE
TO FAVOR A TRACK NE ACROSS NRN LWR MI BASED ON SEVERAL DAYS OF MODEL
RUNS...WHICH SUGGESTS A GOOD POTENTIAL FOR SNOW ACCUMULATIONS TO
REACH/EXCEED WARNING CRITERIA OVER MUCH OF THE FCST AREA. NE TO N
FLOW UPSLOPE/LAKE ENHANCEMENT DURING THE SYNOPTIC FORCING STILL
POINTS TOWARD THE HIGH TERRAIN OF NCNTRL UPPER MI BEING FAVORED FOR
THE GREATEST SNOW TOTALS. RAPID MOVEMENT OF THE SYSTEM AND THE LACK
OF A WELL ORGANIZED MID LEVEL CENTER WILL KEEP SNOW AMOUNTS FROM
GETTING ESPECIALLY HIGH. CONSIDERING THE LACK OF SYNOPTIC STORM
SYSTEMS THAT HAVE AFFECTED UPPER MI DURING THIS COLD SEASON...THIS
SHOULD BE A GOOD SNOW EVENT IF THE SYSTEM INTENSITY AND TRACK WORKS
OUT AS EXPECTED NOW.
FOLLOWING THE MID WEEK STORM...LES WILL BE THE RULE OFF LAKE
SUPERIOR THRU LATE WEEK IN GENERAL W TO NW LOW-LEVEL FLOW UNDER
850MB TEMPS BTWN -14 AND -20C. LOOKS LIKE THERE MAY BE ONE OR MORE
SHORTWAVES PASSING TO PROVIDE BRIEF PERIODS OF ENHANCEMENT TO THE
LES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1253 PM EST SAT JAN 30 2016
W TO SW FLOW OF RELATIVELY DRY PACIFIC AIR WILL MAINTAIN VFR
CONDITIONS THROUGH THIS EVENING. DIURNAL COOLING AND A WEAK TROUGH
MOVING INTO UPPER MICHIGAN IS EXPECTED TO BRING IN LOWER CLOUDS
OVERNIGHT WITH MVFR CIGS AT CMX AND SAW AND IFR AT IWD. SOME VSBY
REDUCTION WITH FOG IS ALSO POSSILBE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 550 AM EST SAT JAN 30 2016
STRONG LOW TRACKING OVER NORTHERN ONTARIO THIS MORNING WILL RESULT
IN SOUTHWEST WINDS 20-30 KTS TODAY. WINDS DIMINISH TONIGHT INTO SUN
AS RIDGING MOVES OVERHEAD. A LOW PRESSURE SYSTEMS TRACKING ACROSS
THE CENTRAL GREAT LAKES WILL LIKELY BRING NORTH TO NORTHEAST GALES
TUE NIGHT INTO WED.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...ROLFSON
AVIATION...JLB
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1254 AM EST SAT JAN 30 2016
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 412 PM EST FRI JAN 29 2016
...WINTRY MIX OF PRECIPITATION TONIGHT...
STRONG SPLIT FLOW PATTERN ALOFT ACROSS THE CONUS TODAY. DECENT JET
IS PRESENT OVER UPPER LAKES IN NW FLOW ALOFT. RIDGING HAS MOVED FM
CNTRL CONUS TO WESTERN GREAT LAKES BUT STRONG SHORTWAVE TROUGH WITH
ASSOCIATED SFC LOW IS OVER CENTRAL MANITOBA. WARM AIR ADVECTION
ALOFT TO THE SOUTH OF THAT SYSTEM WITH H85 TEMPS AT 12Z +10C AT ABR
AND -6C AT INL. SMALLER SHORTWAVE ON SOUTH EDGE OF TROUGH UPSTREAM
OVER DAKOTAS MOVES FM NORTHWEST MN THIS EVENING THEN ACROSS UPR
MICHIGAN AND LK SUPERIOR LATE TONIGHT AND OVER QUEBEC BY MIDDAY
SATURDAY. ASSOCIATED SFC LOW FOLLOWS SUIT...TRACKING ACROSS ONTARIO
AND PUSHING A WARM FRONT OVER UPPER LAKES. PRECIP FORMING OVER MN IS
TIED TO THE SHORTWAVE AND STRONG WARM AIR ADVECTION. EXPECT PRECIP
TO INCREASE AS IT MOVES OVER WESTERN UPR MICHIGAN LATE EVENING AND
OVER REST OF CWA THROUGH THE OVERNIGHT HOURS.
PTYPE WILL BE CONCERN AS RAP/HRRR/NAM SHOW PORTION OF WARM NOSE
ALOFT MAKES IT INTO SW UPR MICHIGAN. MAY BE WARM ENOUGH ALOFT 850-
800MB AOA +3C TO BRIEFLY TURN PRECIP TO FZRA OVER FAR WEST.
ELSEWHERE OVER WEST HALF...SLEET WILL BE POSSIBLE AS WARM LAYER
TEMPS RISE TO +1-2C. HEAVIEST QPF IS PLANNED FOR KEWEENAW. BLEND OF
SHORT TERM HIGH RES GUIDANCE POINTS TO 0.3+ INCHES OVER KEWEENAW
WITH LESSER AMOUNTS OVER REST OF CWA...TAPERING TO LESS THAN 0.10
INCH OVER FAR SOUTH. WITH QPF HIGHEST OVER KEWEENAW AS THAT AREA IS
ALONG TRACK OF SHORTWAVE WENT WITH WINTER WEATHER ADVY FOR SNOW
AMOUNTS MAINLY 2-4 INCHES. IF HRRR OUTPUT IS CORRECT...ISOLD AMOUNTS
AROUND 5 INCHES WOULD NOT BE OUT OF QUESTION MOHAWK TO COPPER
HARBOR. OVER REST OF UPR MICHIGAN...SNOW AMOUNTS WILL BE IN THE 1-3
INCH RANGE. SPS WAS ISSUED TO COVERED SLIPPERY ROADS LATER THIS
EVENING AND OVERNIGHT.
ON SATURDAY...WARM FRONT BLOWS THROUGH IN THE MORNING. MID-LEVEL
MOISTURE IS SCOURED OUT AS THE SHORTWAVE EXITS. ANY PRECIP EARLY
ON WILL BE IN THE FORM OF FZDZ. UPSLOPE WEST WINDS MAY KEEP LOW
CLOUDS AND SOME DZ OVER KEWEENAW INTO THE MIDDAY HOURS...BUT
ELSEWHERE LOW CLOUDS SHOULD GRADUALLY DECREASE. TEMPS ALOFT...JUST
ALOFT AT 925-900MB ARE PRETTY WARM ON THE POSITIVE SIDE OF 0C. MIXING
TO 925MB SUPPORTS MAX TEMPS INTO LOW 40S FOR DOWNSLOPE AREAS. IF WE
CAN MIX TO 900MB...AROUND 3KFT...TEMPS MAY JUMP EVEN HIGHER. WILL ALL
DEPEND ON EXTENT OF SUNSHINE/MIXING. COULD BE BREEZY ON KEWEENAW WITH
WSW WINDS UP TO 20 MPH AND SOME HIGHER GUSTS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 417 PM EST FRI JAN 29 2016
BEGINNING SAT NIGHT...A SHORTWAVE MOVING IN FROM THE NORTHERN PLAINS
WILL PUSH A SFC TROUGH INTO THE AREA. FORCING ASSOC WITH THE
SHORTWAVE COULD SUPPORT SOME LIGHT SNOW ACROSS THE CWA LATE EVENING
INTO OVERNIGHT...AND POSSIBLY A MIX OF SNOW...RAIN OR FREEZING RAIN
OVER SOUTH CENTRAL COUNTIES.
SUN/SUN NIGHT...THE GFS AND NAM ARE SHOWING MORE INTERACTION BETWEEN
A COUPLE OF SHORTWAVES TRACKING ACROSS THE CONUS...RESULTING IN A
DEEPER WAVE TAKING ON A NEGATIVE TILT AS IT SHIFTS ACROSS THE WRN
GREAT LAKES REGION. TO VARYING DEGREES...THE GFS HAS GENERALLY
INDICATED SUCH A SCENARIO FOR SEVERAL RUNS...AND NOW THE NAM HAS
JOINED SUIT THE LAST FEW RUNS. THE GFS IS A BIT QUICKER THAN THE NAM
BRINGING MODERATE TO HEAVY SNOW INTO THE AREA ALREADY ON SUN WHILE
THE NAM INDICATES A POTENTIAL FOR MODERATE TO HEAVY SNOW MAINLY SUN
NIGHT. BOTH MODELS WOULD SUPPORT A HEADLINE EVENT FOR MODERATE TO
HEAVY SNOWFALL AFFECTING MUCH OF THE CWA DURING THE PERIOD.
THE 12Z CANADIAN HAS NOW ALSO TRENDED DEEPER AND FARTHER NORTH WITH
SHORTWAVE AND ASSOC SFC LOW PER NAM AND GFS BUT THE 12Z ECMWF
REMAINS WEAKER AND FARTHER SOUTH ONLY ADDING TO FCST UNCERTAINTY. WL
LIKELY NEED TO BUMP POPS UP A BIT TO REFLECT MODEL CONSENSUS TRENDS
OF STRONGER SYSTEM TRACKING FARTHER NORTH...BUT THIS SYSTEM WILL
DEFINITELY BE ONE TO WATCH OVER THE NEXT FEW MODEL RUNS. IF MODELS
BEGIN TO CONVERGE ON DEEPER AND FARTHER NORTH SOLUTION...WILL LIKELY
NEED WSW HEADLINES FOR A GOOD PORTION OF THE FCST AREA.
MON/MON NIGHT...AFTER ANY LINGERING PCPN ENDS FOLLOWING THE PASSAGE
OF THE SHORTWAVE TO THE E...NW FLOW LOWERING 850MB TEMPS DOWN TO -12
TO -16C FOR AT LEAST A TIME WILL GENERATE SOME LIGHT LES UNDER A LOW
INVERSION.
TUE-WED...GFS/ECMWF/CANADIAN MODELS STILL SHOWING MEANINGFUL
DIFFERENCES REGARDING TRACK OF A POTENTIAL SIGNIFICANT WINTER STORM
TO AFFECT THE GREAT LAKES REGION LATER TUE/WED NEXT WEEK. A NUMBER
OF GFS ENSEMBLES AND CANADIAN ENSEMBLES INCLUDING THE 12Z
OPERATIONAL GFS ARE SUPPORTIVE OF A STRONGER AND FARTHER NORTH SFC
LOW TRACK THROUGH CENTRAL TO NORTHERN LOWER MI WHICH WOULD RESULT IN
MODERATE TO POSSIBLY HEAVY SNOW FOR PROBABLY AT LEAST THE CENTRAL
AND ERN COUNTIES OF UPPER MI. ON THE OTHER HAND...THE 00/12Z
OPERATIONAL ECMWF/CANADIAN/UKMET ARE TRENDING FARTHER SOUTH AND
WEAKER WITH STORM SYSTEM...TRACKING IT THROUGH FAR SRN LOWER MI AND
ACROSS FAR SOUTHERN LAKE HURON WHICH WOULD KEEP MUCH OF THE SYSTEM
SNOW FARTHER SOUTH OF UPPER MI. THE MODEL UNCERTAINTY DEFINITELY
ARGUES FOR TAKING A CONSERVATIVE APPROACH WHEN DETERMINING THE
POSSIBLE IMPACT OF THIS WINTER STORM FOR UPPER MI. IF THE OPERATIONAL
GFS AND THE MAJORITY OF THE GFS ENSEMBLE RUNS PAN OUT MUCH OF THE
CENTRAL AND EASTERN CWA WILL LIKELY SEE AT LEAST ADVISORY TO POSSIBLE
WARNING LEVEL SNOW AMOUNTS. FAIRLY FAST MOVEMENT OF STORM SYSTEM WILL
WORK TO KEEP SYSTEM FROM PRODUCING WIDESPREAD VERY HEAVY SNOW TOTALS.
IN ADDITION...UPSLOPING/POSSIBLE LAKE ENHANCEMENT (850MB TEMPS FALL
FROM -10 TO -15C DURING THE ENHANCEMENT PHASE OFF THE LAKE) COULD ADD
TO SNOW TOTALS OVER NCNTRL UPPER MI. THIS WILL LIKELY BE CASE EVEN IF
THE WEAKER AND FARTHER SOUTH MODEL SOLUTION OF NON NCEP MODELS PAN
OUT.
THU-FRI...MODELS TREND TOWARD GENERALLY A DRIER AND COOLER PERIOD
FOR LATE NEXT WEEK WITH SOME LINGERING LAKE EFFECT IN WESTERLY WIND
SNOW BELTS OF LAKE SUPERIOR. MODELS HINT AT A WEAK SHORTWAVE MOVING
THROUGH THE AREA WHICH MAY PRODUCE A PERIOD OF LIGHT SNOW/FLURRIES
BUT AT THIS TIME IT DOES NOT LOOK LIKE ANYTHING MORE THAN A DUSTING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1236 AM EST SAT JAN 30 2016
AS A SFC LOW MOVES TO NW ONTARIO OVERNIGHT PERIODS OF SNOW WILL
CONTINUE OVER WEST AND CENTRAL UPPER MICHIGAN. IFR CONDITIONS AT CMX
AND IWD ARE EXPECTED DUE TO VSBY. LATE TONIGHT INTO EARLY SAT AS THE
STEADY SNOW TAPERS SOME FZDZ IS POSSIBLE. THIS IS ALSO WHEN CIGS
WILL HAVE BEST CHANCE TO FALL BLO 010. ONCE THE WARM FRONT
MOVES THROUGH...EXPECT SKIES TO CLEAR OUT AND GUSTY SW-W WINDS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 412 PM EST FRI JAN 29 2016
STRONG LOW TRACKING OVER NORTHERN ONTARIO LATE TONIGHT INTO SATURDAY
MORNING WILL RESULT IN SOUTH WINDS 20-30 KTS...WITH GALES TO 35 KTS
OVER EAST HALF. GALE WARNING WAS ISSUED. WINDS DIMINISH SAT NIGHT
INTO SUN AS RIDGING MOVES OVERHEAD. A COUPLE OF LOW PRESSURE SYSTEMS
TRACKING ACROSS THE CENTRAL GREAT LAKES MAY BRING NORTH TO NORTHEAST
GALES SUN NIGHT INTO MON AND AGAIN TUE NIGHT INTO WED. AT THIS TIME
BEST CHANCE FOR WIDESPREAD GALES WOULD BE TUE NIGHT INTO WED.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR MIZ001-
003.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 AM EST THIS MORNING FOR LSZ266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...VOSS
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS DULUTH MN
320 AM CST SAT JAN 30 2016
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 320 AM CST SAT JAN 30 2016
TODAY...THE NORTHLAND CAN EXPECT A ZONAL FLOW PATTERN...WHICH WILL
BRING RELATIVELY WARM AIR MODIFIED BY THE ROCKY MOUNTAINS. A LOW
OVER EASTERN CENTRAL MANITOBA WILL MOVE EAST ACROSS NORTHERN
ONTARIO. LOW LEVEL CLOUDS ASSOCIATED WITH THE LOW COULD AFFECT THE
FAR NORTHERN FORECAST AREA...OTHERWISE MOST OF THE NORTHLAND
SHOULD ONLY BE AFFECTED BY CIRRUS AS A 110 KNOT UPPER LEVEL JET
MOVES INTO THE SOUTHERN FORECAST FROM THE WEST. THE UPPER LEVEL
CLOUD COVER SHOULD BE RELATIVELY THIN UNTIL THE LATE
AFTERNOON...SO SOME SUNSHINE WILL MAKE IT THROUGH TO HELP WARM UP
THE NORTHLAND. TEMPERATURES WILL ALREADY BE STARTING RELATIVELY IN
THE MIDDLE TO UPPER 20S EARLY THIS MORNING...SO IT SHOULD NOT BE
DIFFICULT TO REACH THE MIDDLE TO UPPER 30S. HOPING THERE IS ENOUGH
SUNSHINE TO HELP MELT MY ICY DRIVEWAY!
TONIGHT...A TROUGH WILL MOVE THROUGH THE UPPER MIDWEST. MOST OF
THE MODELS ARE INDICATING THERE COULD BE LIGHT PCPN NEAR AND IN
THE WAKE OF THE LOW LEVEL TROUGH...BUT MOST MODELS KEEP THIS PCPN
SOUTH AND EAST OF THE FORECAST AREA. THE EXCEPTION IS THE
CANADIAN...BUT SINCE IT IS SUCH AN OUTLIER FROM THE OTHER
MODELS...LEANED ON THE MAJORITY OF THE MODELS. THEREFORE...LOWERED
PCPN CHANCES FROM THE PREVIOUS FORECAST...AND LIMITED THE CHANCES
OF PCPN TO THE FAR SE FORECAST AREA. IF THE PCPN OCCURS...THERE
COULD BE A WINTRY MIXTURE OF FREEZING RAIN AND SNOW. THE UPPER
LEVEL TROUGH WILL BE OVER THE NORTHLAND...WHICH WILL HELP KEEP THE
NORTHLAND PRIMARILY CLOUDY. THE CLOUD COVER SHOULD HELP
BOLSTER TEMPERATURES...SO WEIGHTED THE FORECAST TO THE SLIGHTLY
WARMER ECMWF AND NAM12. LOWS SHOULD BE IN THE LOW TO MIDDLE 20S.
SUNDAY...THE UPPER LEVEL TROUGH WILL CONTINUE MOVING THROUGH THE
NORTHLAND...AND WNW FLOW WILL BRING COOLER AIR INTO THE REGION.
THERE COULD BE LINGERING LIGHT PCPN ACROSS THE FAR SE FORECAST
AREA. THE PCPN COULD BE A WINTRY MIXTURE OF FREEZING RAIN OR SNOW
IN THE MORNING...THEN TRANSITION TO RAIN AND SNOW IN THE AFTERNOON
WITH THE WARMING TEMPERATURES. HIGHS SHOULD RANGE FROM THE UPPER
20S AND LOW 30S ACROSS NE MINNESOTA...TO THE LOWER 30S ACROSS NW
WISCONSIN.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 320 AM CST SAT JAN 30 2016
A SHORT WAVE TROF CROSSES THE FORECAST AREA SUNDAY EVENING.
BEHIND THE TROF...A FAST NW FLOW ALOFT COVERS THE AREA. MODELS
BRING A PIECE OF ENERGY THROUGH NORTHERN MN OVERNIGHT.
MEANWHILE...A SFC TROF WAS NEARBY. DEEPEST MOISTURE IS LOCATED
OVER NORTHERN MN AND HAVE SMALL POPS AS A RESULT. MODEL
DIFFERENCES WITH THE SFC TROF AND OVERALL COVERAGE OF QPF LED TO
SMALL POPS AROUND THE PERIPHERY OF LAKE SUPERIOR AND INTO NW WI
LATE. WITH LIGHT QPF AMOUNTS...SNOW AMOUNTS WILL ALSO BE LIGHT.
ADDITIONAL PIECES OF ENERGY WILL ZIP THROUGH THE REGION ON MONDAY.
HOWEVER...BEST OPPORTUNITY FOR LIGHT SNOW WILL BE RESTRICTED TO
THE SOUTH SHORE OF LAKE SUPERIOR INTO NORTH CENTRAL WI WHERE THE
SFC TROF LINGERS BEFORE DISSOLVING IN THE AFTERNOON. A BRIEF BREAK
ARRIVES MONDAY NIGHT WITH SFC RIDGING OVER THE REGION. MODELS HAVE
COME IN A BIT FARTHER NORTH THAN THE PREVIOUS RUNS FOR TUESDAY AND
TUESDAY NIGHT. USED A BLEND OF THE GFS/ECMWF/PREVIOUS FORECAST FOR
POPS TUESDAY AND TUESDAY NIGHT. THE SNOW WILL BE RESTRICTED TO NW
WI TUESDAY MORNING AS BOTH MODELS PLACE MINOR QPF IN THIS AREA.
THE SNOW SHOULD BEGIN TO RAMP UP TUESDAY AFTERNOON THROUGH TUESDAY
NIGHT. DIFFERENCES BECOME QUITE LARGE IN THE SPEED OF THE SYSTEM
TUESDAY NIGHT...PLACEMENT OF QPF/AMOUNTS. THE GFS IS FASTER AT
MOVING OFF THE HIGHER QPF AMOUNTS WHILE THE ECMWF HANGS A GENEROUS
AMOUNT BACK OVER NW WI AND THROUGH THE TWIN PORTS AND UP THE NORTH
SHORE. THIS PLAYS A HUGE ROLE IN THE SNOW AMOUNTS TUESDAY NIGHT.
WILL HOLD OFF ON ANY HEADLINES UNTIL THE SYSTEM GETS CLOSER AND
THE MODEL DIFFERENCES IMPROVE. THE GFS MAINTAINS ITS QUICKNESS ON
WEDNESDAY WITH THE DEPARTURE OF THIS SYSTEM WHILE THE ECMWF IS
SLOWER. THE ECMWF ALSO DEVELOPS A SFC LOW IN ND WEDNESDAY
AFTERNOON WHILE THE GFS DOES NOT. WILL MAINTAIN THE PREVIOUS
FORECAST OF LOW POPS OVER NW WI AS A RESULT. MODEL DIFFERENCES
BECOME QUITE LARGE AGAIN WEDNESDAY NIGHT. THE ECMWF BRINGS THE ND
SFC LOW INTO MN ALONG WITH A DEEPENING SHORTWAVE TROF. THE GFS HAS
A BROADER LONGWAVE TROF MOVING OVER THE AREA WITH SFC RIDGING.
LEANED ON A BLEND OF THE PREVIOUS FORECAST AND THE GFS AND HAVE NO
POPS. THE AFOREMENTIONED DIFFERENCES PERSIST ON THURSDAY WITH THE
ECMWF SLOWLY DEPARTING ITS SYSTEM...WHILE THE GFS HAS PIECES OF
ENERGY MOVING THROUGH THE LONG WAVE TROF OVER THE AREA. A BLEND
RESULTS IN LOW POPS. THE DISCREPANCIES CONTINUE THURSDAY NIGHT AND
FRIDAY AND HAVE BLENDED POPS AS A RESULT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1116 PM CST FRI JAN 29 2016
A TROUGH OF LOW PRESSURE AND SHORTWAVE WERE CONTINUING TO MOVE
THROUGH THE NORTHLAND LATE THIS EVENING WITH THE BACK EDGE OF THE
HEAVIER PRECIPITATION STRETCHING FROM THE ARROWHEAD TO NEAR KHYR.
THIS WILL CONTINUE TO MOVE EAST CLEARING THE NORTHLAND BETWEEN
07-08Z...LEAVING BEHIND FLURRIES OR PATCHY FREEZING DRIZZLE.
CLEARING WAS ALREADY MADE IT TO KINL/KBRD AND WILL PROGRESS EAST
OVERNIGHT. THE RAP DOES BRING SOME LOW VFR/MVFR CEILINGS BACK
ALONG THE INTERNATIONAL BORDER LATER TONIGHT...LASTING THROUGH THE
REST OF THE PERIOD.
WINDS WILL BE WEST TO SOUTHWEST TONIGHT...GUSTY AT TIMES...THEN
TURN NORTHWEST OVER NORTHERN MINNESOTA SATURDAY EVENING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 37 23 31 19 / 0 0 10 20
INL 35 23 28 12 / 0 10 10 20
BRD 38 22 32 20 / 0 0 10 10
HYR 38 25 34 21 / 0 10 10 20
ASX 39 25 34 21 / 0 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
SHORT TERM...GROCHOCINSKI
LONG TERM...GSF
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
1116 PM CST FRI JAN 29 2016
.UPDATE...
ISSUED AT 1116 PM CST FRI JAN 29 2016
THE PRECIPITATION WAS DIMINISHING FROM WEST TO EAST LATE THIS
EVENING...SIMILAR TO WHAT THE NAM/RAP HAVE BEEN SHOWING. THE
ADVISORY FOR THE ARROWHEAD AND A PORTION OF NORTHWEST WISCONSIN
REMAINS IN EFFECT THROUGH MIDNIGHT AND WE WILL LIKELY LET THAT
EXPIRE THEN. LIGHT TO MODERATE SNOW WILL CONTINUE THROUGH 7Z...BUT
THEN SHOULD TRANSITION TO FLURRIES OR PATCHY FREEZING DRIZZLE.
FURTHER WEST...WE EXPECT SOME FLURRIES/PATCHY FREEZING DRIZZLE FOR
ANOTHER HOUR OR SO IN FAR EASTERN MINNESOTA...THEN CLEARING LATE.
UPDATE ISSUED AT 600 PM CST FRI JAN 29 2016
STRONG WAA WAS OCCURRING WITH THE LLJ EARLY THIS EVENING ALONG
WITH A SHORTWAVE DIVING INTO MINNESOTA PER LATEST WATER VAPOR
IMAGERY. THESE FEATURES WERE PRODUCING GOOD LIFT FOR A WINTRY MIX
OF SLEET...FREEZING RAIN AND SNOW ACROSS MUCH OF THE NORTHLAND
THIS EVENING. WE ISSUED A WINTER WEATHER ADVISORY FOR MUCH OF THE
AREA THIS EVENING. MN DOT REPORTING MANY ROADS ACROSS NORTHEAST
MINNESOTA WERE ICE COVERED OR PARTIALLY ICE COVERED AND WE EXPECT
THAT TO OCCUR ACROSS PORTIONS OF NORTHWEST WISCONSIN AS WELL.
THE NAM AND SEVERAL OF THE HIGH RES MODELS WERE DEPICTING THE
PRECIP COVERAGE FAIRLY WELL...AND THEY HAVE THE BULK OF THE PRECIP
MOVING OFF AROUND MIDNIGHT...LINGERING A BIT LONGER OVER THE TIP
OF THE ARROWHEAD AND OVER OUR FAR EASTERN WISCONSIN ZONES.
HOWEVER...THEY MODELS DO SEEM TO BE UNDERDOING THE AMOUNT OF WARM
AIR ALOFT AND WE ADJUSTED THE GRIDS FOR MORE FREEZING RAIN THROUGH
THE EARLY EVENING HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 310 PM CST FRI JAN 29 2016
A 40-50 KNOT LOW LEVEL JET WILL CONTINUE TO USHER INCREASING
MOISTURE AND WARMING MID LEVEL TEMPERATURES INTO THE WESTERN LAKE
SUPERIOR REGION THIS EVENING. LATEST RUC ANALYSIS SHOWS AN AREA OF
INCREASING RADAR RETURNS IS CO-LOCATED WITH A CORRIDOR OF MAX
850PHA TEMPS AND PWATS EXCEEDING A HALF INCH OVER NORTHWEST
MINNESOTA. THE AREA OF FORCING AHEAD OF THE UPPER LEVEL
TROUGH/VORT MAX AND PRECIPITATION WILL SPREAD EAST OVER THE
NORTHLAND THROUGH THE NIGHT.
SHORT TERM FOCUS ON PRECIPITATION TYPE AND LIGHT ICE
ACCUMULATIONS OVERNIGHT. ANTICIPATING SURFACE TEMPERATURES TO RISE
A FEW DEGREES THROUGH THE EVENING...DUE TO THE STRONG WARM AIR
ADVECTION. HOWEVER...THERE IS UNCERTAINTY IF TEMPERATURES WILL
WARM ENOUGH TO SUPPORT ALL RAIN FOR MOST AREAS...OR WILL REMAIN MIX
WITH SLEET/FREEZING RAIN FOR THE EVENING. LATEST NAMBUF SOUNDINGS
SHOW PROFILES SUGGEST A FEW HOUR PERIOD OF A WINTRY MIX LATE
TODAY...BEFORE DEEPLY SATURATING AND SUPPORTING ALL SNOW AFTER
1000PM-MIDNIGHT BEHIND THE FRONTAL PASSAGE. AT THIS TIME THE MAIN
THREAT FOR LIGHT ICE ACCUMULATIONS IS FROM THE TWIN PORTS...SOUTH
ALONG THE INTERSTATE 35 CORRIDOR...AND EAST ACROSS NORTHERN
WISCONSIN. PRIMARILY SNOW...WITH LIGHT ACCUMULATIONS OF AN INCH
OR TWO CAN BE EXPECTED IN THE MINNESOTA ARROWHEAD ZONES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 310 PM CST FRI JAN 29 2016
.LONG TERM...
THE LONG TERM PERIOD IS SHAPING UP TO BE QUITE ACTIVE ACROSS THE
NORTHLAND...WITH A COUPLE MAJOR WEATHER SYSTEMS AFFECTING THE REGION
THROUGHOUT THE PERIOD. ON SATURDAY NIGHT...THE FIRST SYSTEM WILL
MOVE INTO THE CENTRAL PLAINS. THE NAM AND GFS ARE IN THE BEST
AGREEMENT...BRINGING THE SURFACE LOW TO JUST SOUTH OF GREEN BAY BY
00Z MONDAY ON BOTH MODELS. THE ECMWF IS DEFINITELY THE OUTLIER WITH
THIS SYSTEM. HAVE INCREASED POPS ACROSS THE SE 1/2 TO 2/3 OF THE
CWA...ALTHOUGH THE BEST CHANCE OF SEEING A WINTRY MIX FOLLOWED BY
SNOW SATURDAY NIGHT AND SUNDAY. COULD SEE SOME SNOW ACCUMULATION
DURING THAT PERIOD...WITH LESS THAN AN INCH IN NE MN...AND 1 TO 3
INCHES IN NW WI. THE FOCUS WILL SHIFT TO THE SOUTH SHORE OF LAKE
SUPERIOR MONDAY AND MONDAY NIGHT...AS HIGH PRESSURE BUILDS IN AND
WINDS BECOME MORE NORTHERLY. THE BIG STORY FOR THE EXTENDED TIME
PERIOD WILL BE THE POTENTIAL FOR LOCALLY HEAVY SNOW AND INTENSE
WINDS ON TUESDAY AND TUESDAY NIGHT. THE MODELS ARE IN BETTER
CONSENSUS REGARDING THIS SYSTEM...WITH THE GREATEST POTENTIAL FOR
SNOW ACCUMULATION ACROSS OUR NW WI AREA. THE ECMWF BRINGS THE LEAST
SNOW TO NW WI...WHILE THE GFS BRINGS THE MOST. WILL CONTINUE TO HIT
NW WI HARDEST...ALTHOUGH IT DOES APPEAR THAT THE HEAVIEST SNOW WILL
BE EVEN A BIT SOUTH OF OUR CWA. STILL A BIT TOO EARLY TO TELL FOR
SURE...BUT A MAJOR WINTER STORM HAS THE POTENTIAL TO COME CLOSE TO
OUR CWA...IF NOT INTO A PORTION OF OUR CWA. SEVERAL INCHES OF SNOW
WILL BE POSSIBLE ACROSS MUCH OF WISCONSIN. GENERALLY SMALL CHANCES
OF SNOW WILL BE POSSIBLE DURING THE LATTER PART OF THE UPCOMING WORK
WEEK. HIGH TEMPERATURES WILL RANGE FROM THE 30S FOR MOST AREAS ON
SUNDAY...TO THE TEENS AND 20S FOR THE REST OF THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1116 PM CST FRI JAN 29 2016
A TROUGH OF LOW PRESSURE AND SHORTWAVE WERE CONTINUING TO MOVE
THROUGH THE NORTHLAND LATE THIS EVENING WITH THE BACK EDGE OF THE
HEAVIER PRECIPITATION STRETCHING FROM THE ARROWHEAD TO NEAR KHYR.
THIS WILL CONTINUE TO MOVE EAST CLEARING THE NORTHLAND BETWEEN
07-08Z...LEAVING BEHIND FLURRIES OR PATCHY FREEZING DRIZZLE.
CLEARING WAS ALREADY MADE IT TO KINL/KBRD AND WILL PROGRESS EAST
OVERNIGHT. THE RAP DOES BRING SOME LOW VFR/MVFR CEILINGS BACK
ALONG THE INTERNATIONAL BORDER LATER TONIGHT...LASTING THROUGH THE
REST OF THE PERIOD.
WINDS WILL BE WEST TO SOUTHWEST TONIGHT...GUSTY AT TIMES...THEN
TURN NORTHWEST OVER NORTHERN MINNESOTA SATURDAY EVENING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 27 38 25 32 / 100 10 20 20
INL 30 35 22 26 / 70 10 0 10
BRD 28 38 25 31 / 70 10 10 20
HYR 24 40 28 34 / 100 10 40 50
ASX 24 43 28 34 / 100 10 30 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
WIZ002>004-008-009.
MN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR MNZ012-
020-021.
LS...NONE.
&&
$$
UPDATE...MELDE
SHORT TERM...GRANING
LONG TERM...DAP
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
900 PM MST SUN JAN 31 2016
.DISCUSSION...
UNSTABLE NORTHWEST FLOW ALOFT, COLD AIR ALOFT, AND
WEAK SHORT WAVE ENERGY PASSING OVER THE AREA, CONTINUES TO GENERATE
AREAS OF VERY LIGHT SNOW. AREAL COVERAGE OF THE SNOW HAS DECREASED
SO, BASED ON HRRR ANALYSIS, HAVE LOWERED POPS FOR A PORTION OF NORTH
CENTRAL MONTANA OVERNIGHT. ISOLATED TO SCATTERED SNOW SHOWERS SHOULD
PERSIST OVERNIGHT NORTH AND EAST OF GREAT FALLS WITH SNOW
ACCUMULATIONS GENERALLY LESS THAN ONE-HALF INCH OVER THE PLAINS.
REMAINDER OF CURRENT FORECAST DETAILS LOOK GOOD INCLUDING
TEMPERATURES.
&&
.AVIATION...
UPDATED 2355Z.
UNSTABLE NORTHWEST FLOW ALOFT AND AN UPPER LEVEL DISTURBANCE PASSING
OVER THE AREA HAS RESULTED IN ISOLATED TO SCATTERED SNOW SHOWERS.
THESE SHOWERS SHOULD DECREASE IN AREAL COVERAGE AFTER 03Z BUT A FEW
ISOLATED SHOWERS WILL LINGER THROUGH THE OVERNIGHT HOURS. SNOW
SHOWERS WILL AGAIN BECOME MORE NUMEROUS AFTER 18Z. VFR CONDITIONS
PREVAIL WITH MVFR/IFR CONDITIONS POSSIBLE IN THE VICINITY OF SNOW
SHOWERS. MOUNTAINS OBSCURED AT TIMES.
&&
.PREV DISCUSSION...ISSUED 232 PM MST SUN JAN 31 2016
TONIGHT THROUGH TUESDAY...A LIGHT NORTHWESTERLY FLOW ALOFT HAS
DEVELOPED OVER THE REGION TODAY. THE FLOW ALOFT...COMBINED WITH
COLD AIR ALOFT AND A WEAK UPPER LEVEL DISTURBANCE MOVING THROUGH
THE REGION...AS ALLOWED FOR SCATTERED SNOW SHOWERS/SNOW GRAINS TO
DEVELOP OVER THE REGION. MOST OF THE SNOW SHOWERS ARE LIGHT IN
INTENSITY...BUT A FEW HEAVIER SNOW SHOWERS WITH VISIBILITIES BELOW
ONE MILE ARE POSSIBLE AT TIMES. THE SNOW SHOWERS WILL CONTINUE
INTO THE OVERNIGHT HOURS AND THROUGH THE DAY ON MONDAY. NEW SNOW
ACCUMULATIONS TONIGHT WILL GENERALLY BE LESS THAN 1/2 INCH AT
LOWER ELEVATIONS AND AROUND 1 INCH IN THE MOUNTAINS. THE SAME
AMOUNT OF SNOW ACCUMULATIONS ARE POSSIBLE ON
MONDAY...HOWEVER...SOME MELTING WILL OCCUR DURING THE LATE
MORNING/AFTERNOON HOURS ON MONDAY REDUCING THE SNOWFALL
ACCUMULATION A BIT. THE MAIN IMPACT FROM THE SNOWFALL WILL BE
QUICKLY REDUCED VISIBILITIES...AND THAT BRIDGES CAN ICE OVER
QUICKER THAN ROADWAY SURFACES. ADDITIONALLY...SOME WET ROADWAYS
WILL GRADUALLY FREEZE OVER THIS EVENING AFTER SUNSET. FOR
TUESDAY...THE NORTHERLY FLOW ALOFT CONTINUES...WITH A FEW
SCATTERED SNOW SHOWERS AS WELL. HOWEVER...AT THIS TIME...MOST OF
THE SNOW SHOWERS ON TUESDAY WILL MAINLY AFFECT MOUNTAIN AREAS.
OVERALL...TEMPERATURES WILL CONTINUE TO BE A FEW DEGREES BELOW
NORMAL THROUGH THE ENTIRE PERIOD BUT NOT QUITE AS COLD AS
PREVIOUSLY THOUGHT. BRUSDA
TUESDAY NIGHT THROUGH SUNDAY...THIS PERIOD BEGINS WITH WEAK
SHORTWAVE TROF STEADILY EXITING INTO SOUTH CENTRAL MT AND NORTHERN
WY. A FEW RESIDUAL SNOW SHOWERS WILL MOVE ACROSS PARTS OF SOUTHWEST
MT AND THE ROCKY MTN FRONT AS THE TROF PASSES THROUGH, BUT ONLY
MINIMAL SNOWFALL AMOUNTS ARE EXPECTED. LATEST ECMWF AND GFS MODEL
SOLUTIONS ARE BACK IN GOOD AGREEMENT ON ARRIVAL OF HIGH PRESSURE
RIDGING FROM WED AFTN THROUGH MIDDAY THURS AND NEXT PACIFIC
SHORTWAVE MOVING THROUGH OUR REGION THURS AFTN AND FRI. THE RIDGE
WILL PROVIDE A SHORT BREAK FROM THE COOL NORTHWEST FLOW ALOFT
EARLIER IN THE WEEK AS WINDS SHIFT MORE WESTERLY. HOWEVER, MODELS
CONTINUE EARLIER TREND OF LIMITING ANY DECENT WARM UP FROM THIS
SHIFT, AS NOTED IN 1000-500 MB THICKNESS VALUES THAT INCREASE BY
AROUND 100-120 METERS (SIGNALING WARM AIR ADVECTION) BY THURS
MORNING BUT ONLY TOP OUT AT ABOUT 5360 METERS (THE VALUE OFTEN
MARKING TEMPS NEAR FREEZING AND RAIN VS SNOW PRODUCTION). MUCH OF
THE REGION WILL ONLY MAKE IT INTO THE UPPER 20S TO MID 30S ON
THURS/FRI, BUT A STRONGER RIDGE WITH SLIGHTLY BETTER ADVECTION
(THICKNESS VALUES UP TO 5430 METERS) WILL FOLLOW FRIDAY`S WEATHER
SYSTEM, PUSHING TEMPS INTO THE MID 30S TO LOW 40S FOR THE WEEKEND.
THE BEST CHANCE FOR PRECIPITATION EAST OF THE CONTINENTAL DIVIDE
WILL BE THURS NIGHT THROUGH FRI MORNING, WITH MUCH OF OUR AREA
SEEING INTERMITTENT PERIODS OF LIGHT SNOW. WITH ONLY MARGINAL
SHORTWAVE DYNAMICS AND LIQUID PRECIP VALUES OF A TENTH OF AN INCH OR
LESS, SNOWFALL ACCUMULATIONS AT LOWER ELEVATIONS SHOULD LIKELY BE
AROUND A TRACE TO A HALF-INCH BEFORE THE SNOW TAPERS OFF FRI
AFTN/EVE.
WARANAUSKAS
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 19 30 16 31 / 30 30 10 20
CTB 15 29 14 30 / 30 20 10 10
HLN 14 25 11 26 / 20 30 20 20
BZN 4 22 3 21 / 20 30 20 20
WEY 0 20 -2 18 / 20 10 10 10
DLN 4 19 2 18 / 20 20 20 20
HVR 19 30 16 32 / 30 30 10 10
LWT 17 29 13 29 / 30 40 20 20
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
WEATHER.GOV/GREATFALLS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
935 PM CST SUN JAN 31 2016
.UPDATE...
ISSUED AT 930 PM CST SUN JAN 31 2016
FOR LATE EVENING UPDATE HAVE ADDED SOME LOW POPS OVER PORTIONS OF
THE WEST AND CENTRAL AS A WEAK WAVE MOVING THROUGH THE REGION IS
PRODUCING SOME LIGHT ECHOS ON AREA RADARS. STILL HAVE NOT HAD ANY
OBSERVATIONS REPORTING SNOW YET...AND WITH THE ECHOS ON THE WEAK
SIDE WILL KEEP POPS ON THE LOW END.
UPDATE ISSUED AT 612 PM CST SUN JAN 31 2016
FOR EARLY EVENING UPDATE HAVE INCREASED CLOUD COVER A BIT OVER
CENTRAL NORTH DAKOTA IN LINE WITH CURRENT SATELLITE. CONSIDERED
FOG FOR LATER TONIGHT OVER THE NORTH CENTRAL AS LATEST HRRR IS
SUGGESTING SOME DEVELOPING FROM THE NORTH...BUT AT THIS TIME SEE
MINIMAL VISIBILITY RESTRICTIONS NORTH OF THE BORDER. WILL KEEP AN
EYE ON THIS AND MAY END UP ADDING IN LATER UPDATES.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 232 PM CST SUN JAN 31 2016
MAIN FORECAST ISSUE IN THE SHORT TERM WILL BE TEMPERATURES AND
CLOUDS. PRETTY QUIET WEATHER WISE WITH A CONTINUED GRADUAL COOLING
TREND.
CURRENTLY...PARTLY SUNNY SKIES ACROSS WESTERN AND CENTRAL NORTH
DAKOTA. NORTHWEST WINDS GENERALLY 10 TO 15 MPH...BUT GUSTING TO
AROUND 25 MPH OVER THE SOUTHWEST. TEMPERATURES WERE MAINLY IN THE
30S AND LOWER 40S.
LATE THIS AFTERNOON...MAYBE A DEGREE OR TWO RISE POSSIBLE YET THIS
AFTERNOON OVER THE SOUTHERN JAMES RIVER VALLEY. ELSEWHERE
TEMPERATURES HAVE REACHED THEIR HIGHS AND WILL BEGIN TO DROP.
TONIGHT AND MONDAY...MESOSCALE MODELS CONTINUE TO ADVERTISE LOW
CEILINGS EXTENDING FROM NORTHWEST INTO SOUTH CENTRAL NORTH DAKOTA
AND THIS IS YET TO MATERIALIZE. THERE IS A BAND OF MID LEVEL
CLOUDS AND EVEN SOME AREAS OF FOG OVER NORTHEAST NORTH
DAKOTA...AND HAS BEEN TRYING TO CREEP INTO THE TURTLE MOUNTAINS
AND NORTHERN JAMES RIVER VALLEY FROM THE EAST. OTHERWISE THERE IS
MORE SUN THAN CLOUDS ACROSS THE CWA THIS AFTERNOON AND THINK
MESOSCALE AND DETERMINISTIC GLOBAL MODELS ARE OVERDOING THE LOW
CLOUDS. WITH THIS SAID...WE ARE AT THE BEGINNING OF A LONG PERIOD
OF COLD ADVECTION AND EXPECT LOWER STRATUS TO MAKE A VISIT. BUT IF
YOU LOOK UPSTREAM YOU DONT SEE MUCH IN THE WAY OF STRATUS UNTIL
YOU GET NORTH OF REGINA SASKATCHEWAN...AND YOU DONT SEE REAL COLD
TEMPERATURES UNTIL WELL INTO CENTRAL SASKATCHEWAN. THEREFORE OUR
FORECAST FOR TONIGHT AND SUNDAY IS ON THE WARMER SIDE OF GUIDANCE
AND WE DONT INTRODUCE THE STRATUS UNTIL LATE TONIGHT INTO MONDAY
MORNING. WE DID INTRODUCE A MENTION OF PATCHY FOG OVER THE
SOUTHERN JAMES RIVER VALLEY LATE TONIGHT INTO MONDAY MORNING AS
THE AREA OF FOG/STRATUS OVER NORTHEAST NORTH DAKOTA TODAY SAGS
SOUTH. MESOSCALE MODELS AND MOS GUIDANCE ARE BOTH INDICATING FOG
IN/NEAR THE SOUTHERN JRV.
COULD SEE A PASSING SNOW SHOWER OR TWO BUT EVEN THE MESOSCALE
MODELS ARE PRETTY MEAGER WITH ANY REFLECTIVITIES TONIGHT INTO
MONDAY MORNING. SO WILL KEEP THE FORECAST DRY FOR NOW.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 232 PM CST SUN JAN 31 2016
THE OVERALL TREND FOR COLDER TEMPERATURES/A RETURN TO NORMAL OR
SLIGHTLY ABOVE NORMAL HIGHS REMAINS ON TRACK. ALSO...SEVERAL ALBERTA
CLIPPER TYPE SYSTEMS WILL SWEEP THROUGH...WITH PERHAPS THE STRONGEST
ONE COMING AT THE END OF THE LONG TERM PERIOD...SUNDAY.
MONDAY NIGHT THROUGH TUESDAY...A LULL IN ANY SIGNIFICANT WEATHER
ACROSS NORTH DAKOTA AS A POTENT WINTER STORM PASSES WELL SOUTH OF
NORTH DAKOTA...IMPACTING THE CENTRAL PLAINS AND INTO THE GREAT LAKES
AND OHIO VALLEY TUESDAY INTO WEDNESDAY. HIGHS WILL COOL TO AVERAGE
FOR THIS TIME OF YEAR UNDER MOSTLY TO PARTLY CLOUDY CONDITIONS.
TUESDAY NIGHT THROUGH SUNDAY...IT WILL BE DURING THIS TIMEFRAME WE
EXPERIENCE FOUR ALBERTA TYPE CLIPPER SYSTEMS/COLD FRONTS SWEEPING
THROUGH. TIMING OF THESE CLIPPER SYSTEMS IS SLATED FOR TUESDAY
NIGHT/WEDNESDAY...THURSDAY NIGHT...FRIDAY NIGHT...AND THE STRONGEST
ONE AS MENTIONED ABOVE SUNDAY/SUNDAY NIGHT.
FOR THE CLIPPER SYSTEM TUESDAY NIGHT/WEDNESDAY...SPOTTY SNOWSHOWERS
WITH UP TO A COUPLE TENTHS OF SNOWFALL ACCUMULATION POSSIBLE FAR
NORTH INTO THE TURTLE MOUNTAINS. HOWEVER WITH NOT MUCH SNOWFALL NOR
WIND ASSOCIATED WITH THIS CLIPPER...EXPECT MINIMAL IMPACTS.
WEDNESDAY NIGHT THROUGH FRIDAY NIGHT...IMPACTS MINIMAL. FOR THURSDAY
NIGHTS CLIPPER...A DUSTING UP TO A COUPLE TENTHS IN THE SOUTHWEST
AND PORTIONS OF SOUTH CENTRAL PER GFS...HOWEVER THE ECMWF PAINTS A
FEW SNOW SHOWERS IN THE TURTLE MOUNTAINS BUT KEEPS THE SOUTHWEST AND
SOUTH CENTRAL DRY. AGAIN A LACK OF ANY SIGNIFICANT WIND OR SNOW
RESULTS IN LITTLE TO NO TRAVEL IMPACT. WINDS BECOME SLIGHTLY BREEZY
FRIDAY AND FRIDAY NIGHT WITH THE NEXT CLIPPER AS BOUNDARY LAYER
WINDS INCREASE TO 20KT-25KT...BUT SNOWFALL POTENTIAL REMAINS LIMITED
TO THE TURTLE MOUNTAINS WITH UP TO A COUPLE TENTHS AT BEST.
SATURDAY THROUGH SUNDAY...BOTH THE GFS AND ECMWF SHOW A MUCH
STRONGER CLIPPER PUSHING THROUGH WITH BOUNDARY LAYER WINDS OF 40KT.
BUFKIT SOUNDINGS SHOW 40-45KT IN THE MIXED LAYER AND AROUND 50KT AT
THE TOP OF THE MIXED LAYER SUNDAY FOR WILLISTON/MINOT/DICKINSON AND
BISMARCK. LIGHT SNOW IS FORECAST TO COINCIDE WITH THE STRONG
WINDS...SO THIS WILL NEED TO BE WATCHED IN THE COMING DAYS. BECAUSE
OF THE CLIPPERS FAST SPEED THROUGH NORTH DAKOTA...SNOWFALL TOTALS
ARE NOT OVERLY IMPRESSIVE/PERHAPS AN INCH OR TWO...BUT WHATEVER DOES
FALL AT THE TIME OF THE STRONG WINDS MAY RESULT IN VISIBILITY
ISSUES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 612 PM CST SUN JAN 31 2016
LCL MVFR CIGS CONTINUE OVER THE AREA. LATER TONIGHT MVFR CIGS ARE
EXPECTED TO BECOME MORE WIDESPREAD...AND WILL REMAIN INTO MONDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...TWH
LONG TERM...KS
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
928 PM CST SUN JAN 31 2016
.UPDATE...
ISSUED AT 927 PM CST SUN JAN 31 2016
ADJUSTED SKY COVER THROUGH THE REMAINDER OF THE EVENING OTHERWISE
CURRENT FORECAST ON TRACK.
UPDATE ISSUED AT 638 PM CST SUN JAN 31 2016
NO SIGNIFICANT CHANGES TO CURRENT FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 253 PM CST SUN JAN 31 2016
THE MAIN ISSUE FOR THE PERIOD WILL BE ANY PATCHY FOG AND LIGHT
SNOW CHANCES OVERNIGHT.
WV LOOP SHOWS A FAIRLY DECENT SHORTWAVE TROUGH MOVING THROUGH
SOUTHERN MANITOBA. SOME SNOW HAS DEVELOPED NEAR THE
SHORTWAVE...BUT VISIBILITY READINGS AT WINNIPEG AND BRANDON HAVE
NOT GONE LOWER THAN 3SM...MORE OFTEN 6 MILES OR ABOVE. MODELS
CONTINUE TO BRING SOME LIGHT QPF INTO OUR NORTHERN COUNTIES THIS
EVENING...EVENTUALLY TRANSITIONING TO THE LAKE OF THE WOODS AREA
TOWARDS MORNING. WILL KEEP SOME 20ISH POPS GOING...BUT DO NOT
THINK WE WILL GET MORE THAN A DUSTING OF SNOWFALL.
THE SHORTWAVE HAS STARTED TO SHOVE SOME STRATUS DOWN INTO OUR
NORTH CENTRAL CWA. SOME LOWERED VISIBILITIES CONTINUE ALONG THE
LEADING EDGE OF THE STRATUS. THIS IS IN ADDITION TO PATCHY FOG
THAT HAS BEEN PERSISTENT IN HANGING ON OVER THE EASTERN COUNTIES.
THE SHORT RANGE MODELS ARE ALL MORE AGGRESSIVE ON BRINGING GOOD
925 TO 850MB MOISTURE DOWN INTO THE CWA TONIGHT. HRRR AND TO SOME
EXTENT THE RAP HAVE FOG FORMING ALONG AND AHEAD OF THE STRATUS.
THINK THAT SOME PATCHY FOG WILL BE POSSIBLE AGAIN THIS EVENING
ACROSS THE NORTHWESTERN TO CENTRAL CWA...WITH THE BEST FOG CHANCES
EVENTUALLY MOVING TO OVER THE SOUTHERN CWA AS THE STRATUS PUSHES
IN FROM THE NORTH. AT THIS POINT THINK THAT THE MAIN FOG WILL BE
ALONG THE FRONT EDGE OF THE CLOUD DECK...BUT WILL HAVE TO KEEP AN
EYE ON THINGS AS THE EVENING PROGRESSES. WITH CLOUDS AND SOME
LIGHT NORTHWEST WINDS TEMPERATURES WILL STAY IN THE UPPER TEENS TO
LOW 20S OVERNIGHT.
MONDAY AND INTO MONDAY NIGHT...THE MAIN ACTIVITY WILL BE WELL TO
OUR SOUTH WITH THE NORTHERN PLAINS UNDER WEAK SFC HIGH PRESSURE
AND COLD AIR ADVECTION. TEMPS WILL CONTINUE TO SEE A SLOW COOLING
TREND...WITH HIGHS IN THE 20S AND LOWS IN THE SINGLE DIGITS AND
TEENS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 253 PM CST SUN JAN 31 2016
TUESDAY AND WEDNESDAY...THE COOLING TREND CONTINUES AS A BROAD
UPPER TROUGH SETS UP FROM ONTARIO DOWN INTO THE SOUTHERN PLAINS.
SFC HIGH PRESSURE AND WEAK COLD AIR ADVECTION WILL CONTINUE TO
DROP TEMPS THROUGH TUESDAY AND TUESDAY NIGHT...ALTHOUGH SOME OF
THE MODELS ARE INDICATING SOME WARM AIR ADVECTION FOR
WEDNESDAY...SO SLOWED THE COOLING TREND. SOME LIGHT PRECIP IS
KICKED UP BY THE WARM AIR ADVECTION...SO INCLUDED SOME VERY LOW
POPS MAINLY IN THE NORTH FOR MID WEEK...AGAIN NOT EXPECTING MUCH
IF ANY ACCUMULATION.
WEDNESDAY NIGHT-SUNDAY...12Z GUIDANCE IS IN GOOD AGREEMENT
INDICATING A FAIRLY PROGRESSIVE LONGWAVE PATTERN THROUGH NEXT
WEEKEND...WITH PREDOMINANTLY NORTHWESTERLY FLOW ALOFT OVER THE
NORTHERN PLAINS. THIS PATTERN DOES NOT FAVOR SIGNIFICANT PRECIP
EVENTS. GLOBAL MODELS DO INDICATE A FEW PROGRESSIVE UPPER SHORTWAVE
TROUGHS LATE IN THE WEEK...WHICH COULD BRING A BIT OF LIGHT
SNOW...SO DO HAVE LOW POPS MENTIONED WED NIGHT AND FRI/FRI NIGHT.
12Z GFS/ECMWF INDICATE A STRONGER PACIFIC SHORTWAVE TROUGH ENTERING
THE PLAINS LATE NEXT WEEKEND...SO ALSO HAVE LOW POPS DURING THAT
TIME.
RUN-TO-RUN MODEL CONSISTENCY HAS BEEN POOR WITH DAY TO DAY TEMP
TRENDS LATELY IN THE EXTENDED. THE COLDEST AIR MASS IS GENERALLY
EXPECTED TO BE ACROSS CENTRAL AND EASTERN CANADA...AND TO WHAT
DEGREE WE TAP THAT COLDER AIR AT TIMES WILL DEPEND ON THE
AMPLIFICATION OF THE UPPER FLOW AIDED BY EMBEDDED SHORTWAVE TROUGHS.
LATEST DETERMINISTIC GFS/ECMWF VARY ON THE FLOW ORIENTATION AND TEMP
FIELDS SIGNIFICANTLY FOR LATE WEEK...AND WILL THEREFOR CONTINUE
TO MAINTAIN MODEL CONSENUS TEMPS FOR NOW...REASONABLY CLOSE TO
SEASONAL NORMS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 638 PM CST SUN JAN 31 2016
ANOTHER CHALLENGING PERIOD AHEAD. BAND OF MVFR/IFR CIGS SPREADING
ESE ACROSS THE NORTHERN FA WITH VFR CONDITIONS ELSEWHERE. MAIN
QUESTION IS IF FOG WILL FORM OVER CLEAR AREAS ACROSS THE SOUTH AND
DEGREE OF LOWER CIGS DEVELOPMENT. HAVE REMAINED OPTIMISTIC WITH
VSBY AND CIGS TONIGHT UNTIL CLEAR SIGNS OF LOWER CIG/VIS
DEVELOPMENT AS GUIDANCE NOT MUCH HELP.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...JR
LONG TERM...JR/MAKOWSKI
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
641 PM CST SUN JAN 31 2016
.UPDATE...
ISSUED AT 638 PM CST SUN JAN 31 2016
NO SIGNIFICANT CHANGES TO CURRENT FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 253 PM CST SUN JAN 31 2016
THE MAIN ISSUE FOR THE PERIOD WILL BE ANY PATCHY FOG AND LIGHT
SNOW CHANCES OVERNIGHT.
WV LOOP SHOWS A FAIRLY DECENT SHORTWAVE TROUGH MOVING THROUGH
SOUTHERN MANITOBA. SOME SNOW HAS DEVELOPED NEAR THE
SHORTWAVE...BUT VISIBILITY READINGS AT WINNIPEG AND BRANDON HAVE
NOT GONE LOWER THAN 3SM...MORE OFTEN 6 MILES OR ABOVE. MODELS
CONTINUE TO BRING SOME LIGHT QPF INTO OUR NORTHERN COUNTIES THIS
EVENING...EVENTUALLY TRANSITIONING TO THE LAKE OF THE WOODS AREA
TOWARDS MORNING. WILL KEEP SOME 20ISH POPS GOING...BUT DO NOT
THINK WE WILL GET MORE THAN A DUSTING OF SNOWFALL.
THE SHORTWAVE HAS STARTED TO SHOVE SOME STRATUS DOWN INTO OUR
NORTH CENTRAL CWA. SOME LOWERED VISIBILITIES CONTINUE ALONG THE
LEADING EDGE OF THE STRATUS. THIS IS IN ADDITION TO PATCHY FOG
THAT HAS BEEN PERSISTENT IN HANGING ON OVER THE EASTERN COUNTIES.
THE SHORT RANGE MODELS ARE ALL MORE AGGRESSIVE ON BRINGING GOOD
925 TO 850MB MOISTURE DOWN INTO THE CWA TONIGHT. HRRR AND TO SOME
EXTENT THE RAP HAVE FOG FORMING ALONG AND AHEAD OF THE STRATUS.
THINK THAT SOME PATCHY FOG WILL BE POSSIBLE AGAIN THIS EVENING
ACROSS THE NORTHWESTERN TO CENTRAL CWA...WITH THE BEST FOG CHANCES
EVENTUALLY MOVING TO OVER THE SOUTHERN CWA AS THE STRATUS PUSHES
IN FROM THE NORTH. AT THIS POINT THINK THAT THE MAIN FOG WILL BE
ALONG THE FRONT EDGE OF THE CLOUD DECK...BUT WILL HAVE TO KEEP AN
EYE ON THINGS AS THE EVENING PROGRESSES. WITH CLOUDS AND SOME
LIGHT NORTHWEST WINDS TEMPERATURES WILL STAY IN THE UPPER TEENS TO
LOW 20S OVERNIGHT.
MONDAY AND INTO MONDAY NIGHT...THE MAIN ACTIVITY WILL BE WELL TO
OUR SOUTH WITH THE NORTHERN PLAINS UNDER WEAK SFC HIGH PRESSURE
AND COLD AIR ADVECTION. TEMPS WILL CONTINUE TO SEE A SLOW COOLING
TREND...WITH HIGHS IN THE 20S AND LOWS IN THE SINGLE DIGITS AND
TEENS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 253 PM CST SUN JAN 31 2016
TUESDAY AND WEDNESDAY...THE COOLING TREND CONTINUES AS A BROAD
UPPER TROUGH SETS UP FROM ONTARIO DOWN INTO THE SOUTHERN PLAINS.
SFC HIGH PRESSURE AND WEAK COLD AIR ADVECTION WILL CONTINUE TO
DROP TEMPS THROUGH TUESDAY AND TUESDAY NIGHT...ALTHOUGH SOME OF
THE MODELS ARE INDICATING SOME WARM AIR ADVECTION FOR
WEDNESDAY...SO SLOWED THE COOLING TREND. SOME LIGHT PRECIP IS
KICKED UP BY THE WARM AIR ADVECTION...SO INCLUDED SOME VERY LOW
POPS MAINLY IN THE NORTH FOR MID WEEK...AGAIN NOT EXPECTING MUCH
IF ANY ACCUMULATION.
WEDNESDAY NIGHT-SUNDAY...12Z GUIDANCE IS IN GOOD AGREEMENT
INDICATING A FAIRLY PROGRESSIVE LONGWAVE PATTERN THROUGH NEXT
WEEKEND...WITH PREDOMINANTLY NORTHWESTERLY FLOW ALOFT OVER THE
NORTHERN PLAINS. THIS PATTERN DOES NOT FAVOR SIGNIFICANT PRECIP
EVENTS. GLOBAL MODELS DO INDICATE A FEW PROGRESSIVE UPPER SHORTWAVE
TROUGHS LATE IN THE WEEK...WHICH COULD BRING A BIT OF LIGHT
SNOW...SO DO HAVE LOW POPS MENTIONED WED NIGHT AND FRI/FRI NIGHT.
12Z GFS/ECMWF INDICATE A STRONGER PACIFIC SHORTWAVE TROUGH ENTERING
THE PLAINS LATE NEXT WEEKEND...SO ALSO HAVE LOW POPS DURING THAT
TIME.
RUN-TO-RUN MODEL CONSISTENCY HAS BEEN POOR WITH DAY TO DAY TEMP
TRENDS LATELY IN THE EXTENDED. THE COLDEST AIR MASS IS GENERALLY
EXPECTED TO BE ACROSS CENTRAL AND EASTERN CANADA...AND TO WHAT
DEGREE WE TAP THAT COLDER AIR AT TIMES WILL DEPEND ON THE
AMPLIFICATION OF THE UPPER FLOW AIDED BY EMBEDDED SHORTWAVE TROUGHS.
LATEST DETERMINISTIC GFS/ECMWF VARY ON THE FLOW ORIENTATION AND TEMP
FIELDS SIGNIFICANTLY FOR LATE WEEK...AND WILL THEREFOR CONTINUE
TO MAINTAIN MODEL CONSENUS TEMPS FOR NOW...REASONABLY CLOSE TO
SEASONAL NORMS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 638 PM CST SUN JAN 31 2016
ANOTHER CHALLENGING PERIOD AHEAD. BAND OF MVFR/IFR CIGS SPREADING
ESE ACROSS THE NORTHERN FA WITH VFR CONDITIONS ELSEWHERE. MAIN
QUESTION IS IF FOG WILL FORM OVER CLEAR AREAS ACROSS THE SOUTH AND
DEGREE OF LOWER CIGS DEVELOPMENT. HAVE REMAINED OPTIMISTIC WITH
VSBY AND CIGS TONIGHT UNTIL CLEAR SIGNS OF LOWER CIG/VIS
DEVELOPMENT AS GUIDANCE NOT MUCH HELP.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...JR
LONG TERM...JR/MAKOWSKI
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
631 PM CST SUN JAN 31 2016
.UPDATE...
ISSUED AT 612 PM CST SUN JAN 31 2016
FOR EARLY EVENING UPDATE HAVE INCREASED CLOUD COVER A BIT OVER
CENTRAL NORTH DAKOTA IN LINE WITH CURRENT SATELLITE. CONSIDERED
FOG FOR LATER TONIGHT OVER THE NORTH CENTRAL AS LATEST HRRR IS
SUGGESTING SOME DEVELOPING FROM THE NORTH...BUT AT THIS TIME SEE
MINIMAL VISIBILITY RESTRICTIONS NORTH OF THE BORDER. WILL KEEP AN
EYE ON THIS AND MAY END UP ADDING IN LATER UPDATES.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 232 PM CST SUN JAN 31 2016
MAIN FORECAST ISSUE IN THE SHORT TERM WILL BE TEMPERATURES AND
CLOUDS. PRETTY QUIET WEATHER WISE WITH A CONTINUED GRADUAL COOLING
TREND.
CURRENTLY...PARTLY SUNNY SKIES ACROSS WESTERN AND CENTRAL NORTH
DAKOTA. NORTHWEST WINDS GENERALLY 10 TO 15 MPH...BUT GUSTING TO
AROUND 25 MPH OVER THE SOUTHWEST. TEMPERATURES WERE MAINLY IN THE
30S AND LOWER 40S.
LATE THIS AFTERNOON...MAYBE A DEGREE OR TWO RISE POSSIBLE YET THIS
AFTERNOON OVER THE SOUTHERN JAMES RIVER VALLEY. ELSEWHERE
TEMPERATURES HAVE REACHED THEIR HIGHS AND WILL BEGIN TO DROP.
TONIGHT AND MONDAY...MESOSCALE MODELS CONTINUE TO ADVERTISE LOW
CEILINGS EXTENDING FROM NORTHWEST INTO SOUTH CENTRAL NORTH DAKOTA
AND THIS IS YET TO MATERIALIZE. THERE IS A BAND OF MID LEVEL
CLOUDS AND EVEN SOME AREAS OF FOG OVER NORTHEAST NORTH
DAKOTA...AND HAS BEEN TRYING TO CREEP INTO THE TURTLE MOUNTAINS
AND NORTHERN JAMES RIVER VALLEY FROM THE EAST. OTHERWISE THERE IS
MORE SUN THAN CLOUDS ACROSS THE CWA THIS AFTERNOON AND THINK
MESOSCALE AND DETERMINISTIC GLOBAL MODELS ARE OVERDOING THE LOW
CLOUDS. WITH THIS SAID...WE ARE AT THE BEGINNING OF A LONG PERIOD
OF COLD ADVECTION AND EXPECT LOWER STRATUS TO MAKE A VISIT. BUT IF
YOU LOOK UPSTREAM YOU DONT SEE MUCH IN THE WAY OF STRATUS UNTIL
YOU GET NORTH OF REGINA SASKATCHEWAN...AND YOU DONT SEE REAL COLD
TEMPERATURES UNTIL WELL INTO CENTRAL SASKATCHEWAN. THEREFORE OUR
FORECAST FOR TONIGHT AND SUNDAY IS ON THE WARMER SIDE OF GUIDANCE
AND WE DONT INTRODUCE THE STRATUS UNTIL LATE TONIGHT INTO MONDAY
MORNING. WE DID INTRODUCE A MENTION OF PATCHY FOG OVER THE
SOUTHERN JAMES RIVER VALLEY LATE TONIGHT INTO MONDAY MORNING AS
THE AREA OF FOG/STRATUS OVER NORTHEAST NORTH DAKOTA TODAY SAGS
SOUTH. MESOSCALE MODELS AND MOS GUIDANCE ARE BOTH INDICATING FOG
IN/NEAR THE SOUTHERN JRV.
COULD SEE A PASSING SNOW SHOWER OR TWO BUT EVEN THE MESOSCALE
MODELS ARE PRETTY MEAGER WITH ANY REFLECTIVITIES TONIGHT INTO
MONDAY MORNING. SO WILL KEEP THE FORECAST DRY FOR NOW.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 232 PM CST SUN JAN 31 2016
THE OVERALL TREND FOR COLDER TEMPERATURES/A RETURN TO NORMAL OR
SLIGHTLY ABOVE NORMAL HIGHS REMAINS ON TRACK. ALSO...SEVERAL ALBERTA
CLIPPER TYPE SYSTEMS WILL SWEEP THROUGH...WITH PERHAPS THE STRONGEST
ONE COMING AT THE END OF THE LONG TERM PERIOD...SUNDAY.
MONDAY NIGHT THROUGH TUESDAY...A LULL IN ANY SIGNIFICANT WEATHER
ACROSS NORTH DAKOTA AS A POTENT WINTER STORM PASSES WELL SOUTH OF
NORTH DAKOTA...IMPACTING THE CENTRAL PLAINS AND INTO THE GREAT LAKES
AND OHIO VALLEY TUESDAY INTO WEDNESDAY. HIGHS WILL COOL TO AVERAGE
FOR THIS TIME OF YEAR UNDER MOSTLY TO PARTLY CLOUDY CONDITIONS.
TUESDAY NIGHT THROUGH SUNDAY...IT WILL BE DURING THIS TIMEFRAME WE
EXPERIENCE FOUR ALBERTA TYPE CLIPPER SYSTEMS/COLD FRONTS SWEEPING
THROUGH. TIMING OF THESE CLIPPER SYSTEMS IS SLATED FOR TUESDAY
NIGHT/WEDNESDAY...THURSDAY NIGHT...FRIDAY NIGHT...AND THE STRONGEST
ONE AS MENTIONED ABOVE SUNDAY/SUNDAY NIGHT.
FOR THE CLIPPER SYSTEM TUESDAY NIGHT/WEDNESDAY...SPOTTY SNOWSHOWERS
WITH UP TO A COUPLE TENTHS OF SNOWFALL ACCUMULATION POSSIBLE FAR
NORTH INTO THE TURTLE MOUNTAINS. HOWEVER WITH NOT MUCH SNOWFALL NOR
WIND ASSOCIATED WITH THIS CLIPPER...EXPECT MINIMAL IMPACTS.
WEDNESDAY NIGHT THROUGH FRIDAY NIGHT...IMPACTS MINIMAL. FOR THURSDAY
NIGHTS CLIPPER...A DUSTING UP TO A COUPLE TENTHS IN THE SOUTHWEST
AND PORTIONS OF SOUTH CENTRAL PER GFS...HOWEVER THE ECMWF PAINTS A
FEW SNOW SHOWERS IN THE TURTLE MOUNTAINS BUT KEEPS THE SOUTHWEST AND
SOUTH CENTRAL DRY. AGAIN A LACK OF ANY SIGNIFICANT WIND OR SNOW
RESULTS IN LITTLE TO NO TRAVEL IMPACT. WINDS BECOME SLIGHTLY BREEZY
FRIDAY AND FRIDAY NIGHT WITH THE NEXT CLIPPER AS BOUNDARY LAYER
WINDS INCREASE TO 20KT-25KT...BUT SNOWFALL POTENTIAL REMAINS LIMITED
TO THE TURTLE MOUNTAINS WITH UP TO A COUPLE TENTHS AT BEST.
SATURDAY THROUGH SUNDAY...BOTH THE GFS AND ECMWF SHOW A MUCH
STRONGER CLIPPER PUSHING THROUGH WITH BOUNDARY LAYER WINDS OF 40KT.
BUFKIT SOUNDINGS SHOW 40-45KT IN THE MIXED LAYER AND AROUND 50KT AT
THE TOP OF THE MIXED LAYER SUNDAY FOR WILLISTON/MINOT/DICKINSON AND
BISMARCK. LIGHT SNOW IS FORECAST TO COINCIDE WITH THE STRONG
WINDS...SO THIS WILL NEED TO BE WATCHED IN THE COMING DAYS. BECAUSE
OF THE CLIPPERS FAST SPEED THROUGH NORTH DAKOTA...SNOWFALL TOTALS
ARE NOT OVERLY IMPRESSIVE/PERHAPS AN INCH OR TWO...BUT WHATEVER DOES
FALL AT THE TIME OF THE STRONG WINDS MAY RESULT IN VISIBILITY
ISSUES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 612 PM CST SUN JAN 31 2016
LCL MVFR CIGS CONTINUE OVER THE AREA. LATER TONIGHT MVFR CIGS ARE
EXPECTED TO BECOME MORE WIDESPREAD...AND WILL REMAIN INTO MONDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...TWH
LONG TERM...KS
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1246 PM CST SAT JAN 30 2016
.UPDATE...
ISSUED AT 1239 PM CST SAT JAN 30 2016
SHORTWAVE TRACKING ALONG THE ND/SD BORDER HAD PRODUCED UP TO ABOUT
A QUARTER INCH OF SNOW OVER A SMALL PORTION OF SOUTHWEST NORTH
DAKOTA. EXPECT MAINLY TRACE AMOUNTS ASSOCIATED WITH THE WAVE AS IT
TRACKS THROUGH THE FAR SOUTH CENTRAL IN CONFLUENT FLOW ALOFT. WILL
STILL KEEP SLIGHT CHANCE POPS AT LEAST THROUGH MID AFTERNOON TO
COVER THIS. MADE SOME ADJUSTMENTS TO TEMPERATURES WITH COOLER
CONDITIONS OVER THE SOUTHWEST AND SOUTH CENTRAL WHERE THE SNOW
FELL. WARMER ACROSS THE NORTH WITH A LOT MORE SUNSHINE.
UPDATE ISSUED AT 856 AM CST SAT JAN 30 2016
FOR THE MORNING UPDATE WILL ADJUST POPS SOME OVER SOUTHWEST NORTH
DAKOTA. LATEST MESOSCALE MODELS LOOK TO BE VERIFYING A LITTLE TOO
FAR SOUTH WHEN COMPARED TO THE LATEST BOWMAN RADAR LOOP. HAVE
ADJUSTED POPS A LITTLE FARTHER NORTH AND UPPED POPS TO HIGHER
CHANCE. STILL PROBABLY PRETTY HARD FOR ANY ONE AREA TO GET
MEASURABLE PRECIP BUT THERE IS ENOUGH GROUND TRUTH WITH SNOW AT
BAKER...A MIX THEN SNOW AT DICKINSON...PLUS RETURNS ON RADAR...TO
JUSTIFY BUMPING UP POPS. MESOSCALE MODELS KEEP CHANCE OF PRECIP
AND EVEN SOME WEAK CAPE OVER THE SOUTHWEST THROUGH THE AFTERNOON
SO WILL LEAVE SMALL POPS AS PREVIOUSLY FORECAST THROUGH THE
AFTERNOON. OTHERWISE NO SIGNIFICANT UPDATES TO THE GOING FORECAST.
UPDATE ISSUED AT 635 AM CST SAT JAN 30 2016
NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE...THOUGH WE DID
PUSH LOW-END POPS A BIT FURTHER EAST INTO FAR SOUTH CENTRAL ND
TODAY BASED ON RECENT HRRR SIMULATIONS AND THE 06 UTC NAM. A MIX
OF RAIN AND SNOW REMAINS PRUDENT IN THE FORECAST IN PLACES WHERE
WE DO HAVE POPS GIVEN THERMAL PROFILES NEAR THE FREEZING MARK.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 347 AM CST SAT JAN 30 2016
THE MAIN FOCUS FOR THE SHORT TERM FORECAST IS PRECIPITATION
CHANCES ACROSS THE SOUTHWEST.
EARLY THIS MORNING A WEAK UPPER LEVEL SHORT WAVE TROUGH WAS
PUSHING ACROSS EASTERN MONTANA. THIS WILL PROVIDE THE ASCENT
NEEDED TO SPARK SOME LIGHT PRECIPITATION TODAY ACROSS THE
SOUTHWEST. BOWMAN RADAR CONTINUES TO INDICATE VERY LIGHT
PRECIPITATION IS POSSIBLE ACROSS THE SOUTHWEST. HOWEVER...NO
SURFACE OBSERVATIONS OR WEBCAMS HAVE RECORDED ANYTHING OF NOTE SO
FAR THIS MORNING. A MIX OF RAIN...FREEZING RAIN...SLEET AND SNOW
IS POSSIBLE WITH TEMPERATURES ALOFT WITHIN ONE OR TWO DEGREES OF
FREEZING AND SURFACE TEMPERATURES ALSO HOVERING AROUND FREEZING.
HOWEVER...SHORT TERM MODELS AND RADAR TRENDS INDICATE ONLY VERY
LIGHT AND SCATTERED PRECIPITATION MAY FALL...THEREFORE...NO MAJOR
IMPACTS ARE ANTICIPATED.
WITH WESTERLY WINDS AND NEARLY NEUTRAL TEMPERATURE ADVECTION
THROUGH MOST OF THE DAY...TEMPERATURES WILL LIKELY CLIMB BACK
INTO THE 40S ACROSS MOST OF THE SOUTH WEST AND SOUTH CENTRAL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 347 AM CST SAT JAN 30 2016
SEASONABLY COLD WEATHER WILL PREVAIL DURING THE LONG TERM...WITH
ONLY A FEW LOW-GRADE OPPORTUNITIES OF LIGHT SNOW.
THE 00 UTC GLOBAL MODEL SUITE REMAINED IN GOOD AGREEMENT WITH ITS
DEPICTION OF NORTHWEST FLOW ALOFT DEVELOPING ACROSS THE REGION AS
A MEAN 500-MB TROUGH BECOMES ESTABLISHED OVER THE CENTRAL UNITED
STATES THIS WEEK. THIS WILL PROVIDE A RELATIVELY STEADY SUPPLY OF
COLD AIR ADVECTION TO THE NORTHERN PLAINS...ESPECIALLY AS LARGER-
SCALE FLOW AMPLIFIES IN RESPONSE TO WARM AIR ADVECTION AND HEIGHT
RISES ALOFT DOWNSTREAM OF THE POWERFUL STORM EXPECTED TO MOVE FROM
THE CENTRAL PLAINS TO THE GREAT LAKES BY MIDWEEK. A COOLING TREND
WILL RESULT WITH HIGHS FALLING FROM 25 TO 35 F SUNDAY TO 10 TO 25
F TUESDAY THROUGH FRIDAY /COLDEST IN NORTH CENTRAL ND/.
WELL-ESTABLISHED CYCLONIC FLOW IN THE EXPECTED WEATHER REGIME MAY
YIELD A LITTLE LIGHT SNOW ON SOME DAYS...ESPECIALLY WHEN EMBEDDED
VORTICITY MAXIMA TRAVERSE THE REGION. THE PREDICTABILITY OF THOSE
FEATURES IS GENERALLY LOW IN THIS PATTERN...BUT THE 00 UTC ECMWF
AND GFS BOTH SUGGESTED WEAK WAVES MAY CROSS THE AREA BOTH MONDAY
AND WEDNESDAY. OUR MODEL-BLEND-DRIVEN FORECAST THUS HAS LOW POPS
IN THOSE TIME PERIODS...MAINLY OVER WESTERN ND WHERE THE THERMAL
GRADIENT IN THE MIDDLE ATMOSPHERE WILL BE GREATEST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1239 PM CST SAT JAN 30 2016
EXPECT MAINLY VFR CONDITIONS THROUGH THE FORECAST PERIOD. WEST TO
NORTHWEST FLOW WILL CONTINUE. A PERIOD OF MVFR CEILINGS THROUGH
20Z AT KDIK AS LIGHT SNOW EXITS THIS AREA. OTHERWISE EXPECT LOW
VFR CONDITIONS HERE AND KBIS WITH ONLY THIN HIGH CLOUDS AT KISN
KMOT. LOWER CEILINGS WILL MOVE INTO THE SOUTHWEST AGAIN ON SUNDAY
WITH POSSIBLE MVFR CEILINGS AT KDIK AFT 15 UTC SUNDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...AJ
LONG TERM...CJS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
910 AM CST SAT JAN 30 2016
.UPDATE...
ISSUED AT 856 AM CST SAT JAN 30 2016
FOR THE MORNING UPDATE WILL ADJUST POPS SOME OVER SOUTHWEST NORTH
DAKOTA. LATEST MESOSCALE MODELS LOOK TO BE VERIFYING A LITTLE TOO
FAR SOUTH WHEN COMPARED TO THE LATEST BOWMAN RADAR LOOP. HAVE
ADJUSTED POPS A LITTLE FARTHER NORTH AND UPPED POPS TO HIGHER
CHANCE. STILL PROBABLY PRETTY HARD FOR ANY ONE AREA TO GET
MEASURABLE PRECIP BUT THERE IS ENOUGH GROUND TRUTH WITH SNOW AT
BAKER...A MIX THEN SNOW AT DICKINSON...PLUS RETURNS ON RADAR...TO
JUSTIFY BUMPING UP POPS. MESOSCALE MODELS KEEP CHANCE OF PRECIP
AND EVEN SOME WEAK CAPE OVER THE SOUTHWEST THROUGH THE AFTERNOON
SO WILL LEAVE SMALL POPS AS PREVIOUSLY FORECAST THROUGH THE
AFTERNOON. OTHERWISE NO SIGNIFICANT UPDATES TO THE GOING FORECAST.
UPDATE ISSUED AT 635 AM CST SAT JAN 30 2016
NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE...THOUGH WE DID
PUSH LOW-END POPS A BIT FURTHER EAST INTO FAR SOUTH CENTRAL ND
TODAY BASED ON RECENT HRRR SIMULATIONS AND THE 06 UTC NAM. A MIX
OF RAIN AND SNOW REMAINS PRUDENT IN THE FORECAST IN PLACES WHERE
WE DO HAVE POPS GIVEN THERMAL PROFILES NEAR THE FREEZING MARK.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 347 AM CST SAT JAN 30 2016
THE MAIN FOCUS FOR THE SHORT TERM FORECAST IS PRECIPITATION
CHANCES ACROSS THE SOUTHWEST.
EARLY THIS MORNING A WEAK UPPER LEVEL SHORT WAVE TROUGH WAS
PUSHING ACROSS EASTERN MONTANA. THIS WILL PROVIDE THE ASCENT
NEEDED TO SPARK SOME LIGHT PRECIPITATION TODAY ACROSS THE
SOUTHWEST. BOWMAN RADAR CONTINUES TO INDICATE VERY LIGHT
PRECIPITATION IS POSSIBLE ACROSS THE SOUTHWEST. HOWEVER...NO
SURFACE OBSERVATIONS OR WEBCAMS HAVE RECORDED ANYTHING OF NOTE SO
FAR THIS MORNING. A MIX OF RAIN...FREEZING RAIN...SLEET AND SNOW
IS POSSIBLE WITH TEMPERATURES ALOFT WITHIN ONE OR TWO DEGREES OF
FREEZING AND SURFACE TEMPERATURES ALSO HOVERING AROUND FREEZING.
HOWEVER...SHORT TERM MODELS AND RADAR TRENDS INDICATE ONLY VERY
LIGHT AND SCATTERED PRECIPITATION MAY FALL...THEREFORE...NO MAJOR
IMPACTS ARE ANTICIPATED.
WITH WESTERLY WINDS AND NEARLY NEUTRAL TEMPERATURE ADVECTION
THROUGH MOST OF THE DAY...TEMPERATURES WILL LIKELY CLIMB BACK
INTO THE 40S ACROSS MOST OF THE SOUTH WEST AND SOUTH CENTRAL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 347 AM CST SAT JAN 30 2016
SEASONABLY COLD WEATHER WILL PREVAIL DURING THE LONG TERM...WITH
ONLY A FEW LOW-GRADE OPPORTUNITIES OF LIGHT SNOW.
THE 00 UTC GLOBAL MODEL SUITE REMAINED IN GOOD AGREEMENT WITH ITS
DEPICTION OF NORTHWEST FLOW ALOFT DEVELOPING ACROSS THE REGION AS
A MEAN 500-MB TROUGH BECOMES ESTABLISHED OVER THE CENTRAL UNITED
STATES THIS WEEK. THIS WILL PROVIDE A RELATIVELY STEADY SUPPLY OF
COLD AIR ADVECTION TO THE NORTHERN PLAINS...ESPECIALLY AS LARGER-
SCALE FLOW AMPLIFIES IN RESPONSE TO WARM AIR ADVECTION AND HEIGHT
RISES ALOFT DOWNSTREAM OF THE POWERFUL STORM EXPECTED TO MOVE FROM
THE CENTRAL PLAINS TO THE GREAT LAKES BY MIDWEEK. A COOLING TREND
WILL RESULT WITH HIGHS FALLING FROM 25 TO 35 F SUNDAY TO 10 TO 25
F TUESDAY THROUGH FRIDAY /COLDEST IN NORTH CENTRAL ND/.
WELL-ESTABLISHED CYCLONIC FLOW IN THE EXPECTED WEATHER REGIME MAY
YIELD A LITTLE LIGHT SNOW ON SOME DAYS...ESPECIALLY WHEN EMBEDDED
VORTICITY MAXIMA TRAVERSE THE REGION. THE PREDICTABILITY OF THOSE
FEATURES IS GENERALLY LOW IN THIS PATTERN...BUT THE 00 UTC ECMWF
AND GFS BOTH SUGGESTED WEAK WAVES MAY CROSS THE AREA BOTH MONDAY
AND WEDNESDAY. OUR MODEL-BLEND-DRIVEN FORECAST THUS HAS LOW POPS
IN THOSE TIME PERIODS...MAINLY OVER WESTERN ND WHERE THE THERMAL
GRADIENT IN THE MIDDLE ATMOSPHERE WILL BE GREATEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 856 AM CST SAT JAN 30 2016
VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES. MVFR CONDITIONS ARE
POSSIBLE AT KDIK THIS MORNING...HOWEVER CONFIDENCE WAS NOT HIGH
ENOUGH TO MENTION IN THE TAF. A LIGHT MIX OF RAIN OR SNOW IS
POSSIBLE AT KDIK THIS MORNING BUT ONCE AGAIN CONFIDENCE IS NOT
VERY HIGH.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...AJ
LONG TERM...CJS
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
635 AM CST SAT JAN 30 2016
.UPDATE...
ISSUED AT 635 AM CST SAT JAN 30 2016
NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE...THOUGH WE DID
PUSH LOW-END POPS A BIT FURTHER EAST INTO FAR SOUTH CENTRAL ND
TODAY BASED ON RECENT HRRR SIMULATIONS AND THE 06 UTC NAM. A MIX
OF RAIN AND SNOW REMAINS PRUDENT IN THE FORECAST IN PLACES WHERE
WE DO HAVE POPS GIVEN THERMAL PROFILES NEAR THE FREEZING MARK.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 347 AM CST SAT JAN 30 2016
THE MAIN FOCUS FOR THE SHORT TERM FORECAST IS PRECIPITATION
CHANCES ACROSS THE SOUTHWEST.
EARLY THIS MORNING A WEAK UPPER LEVEL SHORT WAVE TROUGH WAS
PUSHING ACROSS EASTERN MONTANA. THIS WILL PROVIDE THE ASCENT
NEEDED TO SPARK SOME LIGHT PRECIPITATION TODAY ACROSS THE
SOUTHWEST. BOWMAN RADAR CONTINUES TO INDICATE VERY LIGHT
PRECIPITATION IS POSSIBLE ACROSS THE SOUTHWEST. HOWEVER...NO
SURFACE OBSERVATIONS OR WEBCAMS HAVE RECORDED ANYTHING OF NOTE SO
FAR THIS MORNING. A MIX OF RAIN...FREEZING RAIN...SLEET AND SNOW
IS POSSIBLE WITH TEMPERATURES ALOFT WITHIN ONE OR TWO DEGREES OF
FREEZING AND SURFACE TEMPERATURES ALSO HOVERING AROUND FREEZING.
HOWEVER...SHORT TERM MODELS AND RADAR TRENDS INDICATE ONLY VERY
LIGHT AND SCATTERED PRECIPITATION MAY FALL...THEREFORE...NO MAJOR
IMPACTS ARE ANTICIPATED.
WITH WESTERLY WINDS AND NEARLY NEUTRAL TEMPERATURE ADVECTION
THROUGH MOST OF THE DAY...TEMPERATURES WILL LIKELY CLIMB BACK
INTO THE 40S ACROSS MOST OF THE SOUTH WEST AND SOUTH CENTRAL.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 347 AM CST SAT JAN 30 2016
SEASONABLY COLD WEATHER WILL PREVAIL DURING THE LONG TERM...WITH
ONLY A FEW LOW-GRADE OPPORTUNITIES OF LIGHT SNOW.
THE 00 UTC GLOBAL MODEL SUITE REMAINED IN GOOD AGREEMENT WITH ITS
DEPICTION OF NORTHWEST FLOW ALOFT DEVELOPING ACROSS THE REGION AS
A MEAN 500-MB TROUGH BECOMES ESTABLISHED OVER THE CENTRAL UNITED
STATES THIS WEEK. THIS WILL PROVIDE A RELATIVELY STEADY SUPPLY OF
COLD AIR ADVECTION TO THE NORTHERN PLAINS...ESPECIALLY AS LARGER-
SCALE FLOW AMPLIFIES IN RESPONSE TO WARM AIR ADVECTION AND HEIGHT
RISES ALOFT DOWNSTREAM OF THE POWERFUL STORM EXPECTED TO MOVE FROM
THE CENTRAL PLAINS TO THE GREAT LAKES BY MIDWEEK. A COOLING TREND
WILL RESULT WITH HIGHS FALLING FROM 25 TO 35 F SUNDAY TO 10 TO 25
F TUESDAY THROUGH FRIDAY /COLDEST IN NORTH CENTRAL ND/.
WELL-ESTABLISHED CYCLONIC FLOW IN THE EXPECTED WEATHER REGIME MAY
YIELD A LITTLE LIGHT SNOW ON SOME DAYS...ESPECIALLY WHEN EMBEDDED
VORTICITY MAXIMA TRAVERSE THE REGION. THE PREDICTABILITY OF THOSE
FEATURES IS GENERALLY LOW IN THIS PATTERN...BUT THE 00 UTC ECMWF
AND GFS BOTH SUGGESTED WEAK WAVES MAY CROSS THE AREA BOTH MONDAY
AND WEDNESDAY. OUR MODEL-BLEND-DRIVEN FORECAST THUS HAS LOW POPS
IN THOSE TIME PERIODS...MAINLY OVER WESTERN ND WHERE THE THERMAL
GRADIENT IN THE MIDDLE ATMOSPHERE WILL BE GREATEST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 635 AM CST SAT JAN 30 2016
VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES. MVFR CONDITIONS ARE
POSSIBLE AT KDIK THIS MORNING...HOWEVER CONFIDENCE WAS NOT HIGH
ENOUGH TO MENTION IN THE TAF. A LIGHT MIX OF RAIN OR SNOW IS
POSSIBLE AT KDIK/KISN THIS MORNING BUT ONCE AGAIN CONFIDENCE IS
NOT VERY HIGH.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...AJ
LONG TERM...CJS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS Tulsa OK
1111 PM CST FRI JAN 29 2016
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
VFR conditions will prevail through the forecast period for all sites.
&&
.PREV DISCUSSION... /ISSUED 930 PM CST FRI JAN 29 2016/
DISCUSSION...
A weak surface boundary will move into the area tonight shifting
the winds to the northwest across parts of eastern Oklahoma. This
boundary will wash out by midday Saturday with south winds
returning to all areas. Temperatures today greatly exceeded
expectations and model low level thermal progs and the latest
experimental HRRR data suggests Saturday will only be a few
degrees cooler than today in northeast Oklahoma, and as warm as
today across southeast Oklahoma and northwest Arkansas. Thus, have
raised high temperatures Saturday by at least 5 degrees
everywhere, and there is a chance this may not be quite warm
enough. Have also made minor adjustments to the overnight low
tonight at KBVO. The rest of the forecast looks good at this
time.
Update on the way.
TSA Watches/Warnings/Advisories...
OK...NONE.
AR...NONE.
$$
SHORT TERM...07
LONG TERM....05
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 39 70 51 59 / 0 0 0 0
FSM 42 74 51 66 / 0 0 0 0
MLC 42 72 52 63 / 0 0 0 0
BVO 33 65 46 58 / 0 0 0 0
FYV 41 69 49 60 / 0 0 0 10
BYV 41 68 48 63 / 0 0 0 10
MKO 40 68 50 62 / 0 0 0 0
MIO 39 67 49 59 / 0 0 0 10
F10 40 69 51 61 / 0 0 0 0
HHW 43 71 52 67 / 0 0 10 10
&&
.TSA Watches/Warnings/Advisories...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...07
AREA FORECAST DISCUSSION
NWS MEDFORD OR
817 PM PST FRI JAN 29 2016
.UPDATED AVIATION DISCUSSION.
.DISCUSSION...A COLD FRONT HAS SWEPT THROUGH THE FORECAST AREA...AND
THE RELATIVELY WARM PATTERN WITH HIGH SNOW LEVELS HAS ENDED. SNOW
LEVELS ARE NOW ABOUT 3500 FEET AND WILL CONTINUE TO FALL
OVERNIGHT. FAVORABLE JET DYNAMICS IS ENHANCING PRECIPITATION OVER
NORTHEAST CALIFORNIA...AND WE HAVE ISSUED A WINTER WEATHER
ADVISORY AT WSWMFR FOR SEVERAL INCHES OF SNOW EXPECTED THIS
EVENING IN LOCATIONS SUCH AS ALTURAS. THE HRRR SHOWED THIS ENHANCED
AREA OF PCPN THE BEST...AND IT SHOWS SNOW DIMINISHING THERE BY
MIDNIGHT. ELSEWHERE...SNOW IS EXPECTED TO IMPACT THE FOOTHILLS OF
THE CASCADES TONIGHT IN JACKSON AND DOUGLAS COUNTIES AND THE WSW
CONTINUES FOR THOSE AREAS INTO SATURDAY MORNING.
WESTERLY FLOW ALOFT WILL HELP BRING 3-6 MORE INCHES OF SNOW TO THE
CASCADES TONIGHT INTO TOMORROW. TRAVELERS INTO THE MOUNTAINS CAN
EXPECT SOME SNOW COVERED ROADS AND LOWER VISIBILITIES THROUGH
SATURDAY.
SATURDAY WILL FEATURE THE AFOREMENTIONED RAIN AND SNOW
SHOWERS...WITH SNOW LEVELS DIPPING TO ABOUT 2000 FEET. NAM12 OUTPUT
SUGGESTS ENOUGH INSTABILITY FOR THUNDERSTORMS FOR MUCH OF THE WEST
SIDE...GENERALLY ALONG AND WEST OF I-5.
SEE THE PREVIOUS DISCUSSION BELOW FOR MORE DETAILS ON THE SHOWERY
AND COLD CONDITIONS EXPECTED THIS WEEKEND.
&&
.AVIATION...FOR THE 30/06Z TAF CYCLE...MVFR/IFR AND NEAR TOTAL
TERRAIN OBSCURATION IN SHOWERS IS EXPECTED THROUGH THE NIGHT. THE
WORST CONDITIONS WILL LIKELY BE IN THE CASCADES AND IN MODOC COUNTY
WHERE SNOW SHOWERS WILL BRING IFR VISIBILITIES. ANOTHER WEAK
DISTURBANCE WILL BRING A MORE FOCUSED PERIOD OF SHOWERS TO THE COAST
AROUND MIDNIGHT WITH CIGS POTENTIALLY LOWERING TO MVFR AT TIMES.
SCATTERED TO WIDESPREAD SHOWERS ARE EXPECTED ON SATURDAY...MAINLY
FROM THE CASCADES WEST. ADDITIONALLY...THUNDERSTORMS ARE POSSIBLE
OVERNIGHT INTO TOMORROW OVER THE COASTAL WATERS TO AREAS JUST
INLAND. FB/SK
&&
.MARINE...UPDATED 800 PM PST FRI 29 JAN 2016...STEEP SEAS AND WEST
SWELL WILL GRADUALLY SUBSIDE OVER THE WEEKEND BUT WILL REMAIN
HAZARDOUS TO SMALL CRAFT UNTIL EARLY NEXT WEEK. HIGH PRESSURE WILL
BUILD INTO THE WATERS LATE THIS WEEKEND. WEAK LOW PRESSURE WILL
ARRIVE TUESDAY MORNING BUT WINDS SHOULD REMAIN BELOW SMALL CRAFT
ADVISORY CRITERIA. SK
&&
.PREV DISCUSSION... /ISSUED 235 PM PST FRI JAN 29 2016/
SHORT TERM...AS AN UPPER LEVEL TROUGH CENTERED TO THE NORTH MOVES
INLAND AND VERY COLD AIR ALOFT MOVES INTO THE AREA, SHOWERS WILL
SPREAD INLAND FROM THE NORTHWEST AND SNOW LEVELS WILL LOWER.
AHEAD OF THE SHOWERS, RAIN AND SNOW WILL CONTINUE OVER PORTIONS OF
SOUTHERN OREGON AND ACROSS NORTHERN CALIFORNIA LATE THIS AFTERNOON
AND THIS EVENING. SHOWERS ARE EXPECTED TO INCREASE OVER THE AREA
TODAY AND SATURDAY MORNING.
SNOW LEVELS ARE CURRENTLY AROUND 3500 TO 4000 FEET WEST OF THE
CASCADES IN SOUTHERN OREGON AND 4000 TO 6000 FEET EAST OF THE
CASCADES AND IN NORTHERN CALIFORNIA. SNOW LEVELS WILL LOWER TO
2500 FEET THIS EVENING FROM THE SOUTHERN OREGON CASCADES WESTWARD
AND BETWEEN 2500 TO 4500 FEET EAST OF THE CASCADES AND IN NORTHERN
CALIFORNIA. THEN SNOW LEVELS DROP FURTHER, LOWERING DOWN TO 2000
FEET LATE TONIGHT AND SATURDAY MORNING. LOW SNOW LEVELS COMBINED
WITH INCREASING SHOWER ACTIVITY TONIGHT AND SATURDAY MORNING WILL
BRING LIGHT TO MODERATE SNOW ACCUMULATIONS TO THE AREA, WITH
MODERATE SNOW OVER THE SOUTHERN OREGON CASCADES AND THE WESTERN
SLOPES OF THE SOUTHERN OREGON CASCADES WHERE AROUND 1 TO 4 INCHES
IS EXPECTED ABOVE 2000 FEET AND 4 TO 6 INCHES ABOVE 3000 FEET
WITH LOCALLY HIGHER AMOUNTS UP TO 10 INCHES ABOVE 5500 FEET,
ESPECIALLY IN THE CRATER LAKE AREA. LOCALLY SNOW OR A RAIN/SNOW
MIX MAY FALL DOWN TO 1500 FEET ELEVATION SATURDAY MORNING BUT
EXPECT LITTLE IF ANY ACCUMULATIONS.
SHOWERS ARE FORECAST TO CONTINUE THROUGH THE DAY SATURDAY WITH
ADDITIONAL LIGHT SNOW ACCUMULATIONS AND SNOW LEVELS AROUND 2500
TO 3000 FEET.
SATURDAY NIGHT INTO SUNDAY, COLDER CONDITIONS WILL DEVELOP AS THE
UPPER LEVEL TROUGH BECOMES CENTERED OVER THE AREA. MODELS ARE IN
GOOD AGREEMENT THAT SHOWERS WILL BE MAINLY LIMITED TO THE COASTAL
AREAS AND OVER THE COASTAL WATERS SATURDAY NIGHT AND SUNDAY. THEN
AS DAYTIME INSTABILITY INCREASES WITH THE COLD TROUGH OVERHEAD,
EXPECT SHOWERS TO INCREASE DURING THE DAY SUNDAY, MAINLY OVER THE
HIGHER TERRAIN FROM THE CASCADES WEST. SNOW LEVELS ARE FORECAST
AROUND 500 TO 1500 FEET SUNDAY MORNING RISING TO 2000 TO 2500
FEET IN THE AFTERNOON. THE FLOW ALOFT WILL BE MORE NORTHERLY AND
NOT AS MOIST. SO, SNOW ACCUMULATIONS ARE FORECAST TO REMAIN LIGHT.
MODELS SHOW DIFFERENCES IN THE AMOUNT OF SHOWER ACTIVITY AND
COVERAGE FOR SUNDAY INTO SUNDAY NIGHT THOUGH AND WILL NEED TO
MONITOR THE FORECAST DURING THIS PERIOD.
LONG TERM...MONDAY THROUGH FRIDAY...HIGH PRESSURE AND UPPER LEVEL
RIDGING WILL BEGIN TO RETURN MONDAY, AND THIS SHOULD BRING A
DRYING TREND TO THE FORECAST AREA. THE UPPER LEVEL FLOW WILL BE
FROM THE NORTHWEST THROUGH ABOUT WEDNESDAY NIGHT OR THURSDAY, AND
THIS WILL PROVIDE AN OPPORTUNITY FOR A SHORTWAVE TO TRAVERSE OVER
THE REGION TUESDAY AND TUESDAY NIGHT. THERE IS SOME DIFFERENCE
BETWEEN THE ECMWF AND GFS SOLUTION REGARDING THIS WAVE, WITH THE
GFS PRODUCING A STRONGER WAVE THAT MOVES DIRECTLY OVER SOUTHERN
OREGON, WHILE THE ECMWF SHOWS A WEAKER WAVE SLIDING BY JUST TO OUR
NORTH. WITH ENSEMBLES SHOWING A WIDE RANGE OF VARIABILITY DURING
THIS TIME, CONFIDENCE IS LOW IN EITHER SPECIFIC SOLUTION. HAVE
THEREFORE TRENDED TOWARDS A GENERAL BLEND, AND KEPT A SLIGHT
CHANCE OR CHANCE OF PRECIPITATION FROM TUESDAY INTO EARLY
WEDNESDAY MORNING. SNOW LEVELS DURING THIS SYSTEM WILL REMAIN
BELOW 3000 FEET, AND MAY EVEN APPROACH THE VALLEY FLOORS AT TIMES,
BUT AS PRECIPITATION SHOULD BE LIGHT, NO MAJOR IMPACTS ARE
EXPECTED.
AFTER ANOTHER BRIEF PERIOD OF HIGH PRESSURE AND DRIER CONDITIONS
WEDNESDAY NIGHT INTO THURSDAY MORNING, ANOTHER WAVE IS EXPECTED
THURSDAY AFTERNOON. MODELS ARE IN SURPRISINGLY GOOD AGREEMENT FOR
THIS WAVE, BUT AS THERE IS LITTLE TO INDICATE THAT THIS WOULD BE A
STRONG SYSTEM, HAVE KEPT PRECIPITATION CHANCES ON THE LOW SIDE. SNOW
LEVELS SHOULD JUMP UP TO ABOUT 5000 FEET, SO AGAIN, LITTLE IMPACT IS
EXPECTED. HIGH PRESSURE AND RIDGING WILL THEN RETURN AND REMAIN IN
CONTROL THROUGH THE END OF THE TERM. -BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 AM PST SATURDAY FOR ORZ025.
WINTER WEATHER ADVISORY UNTIL 10 AM PST SATURDAY FOR ORZ026.
CA...WINTER WEATHER ADVISORY UNTIL 11 PM PST THIS EVENING FOR
CAZ083-085.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PST SUNDAY
FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST SUNDAY
FOR PZZ370-376.
$$
NSK/BPN/FJB
AREA FORECAST DISCUSSION
NWS MEDFORD OR
1035 PM PST FRI JAN 29 2016
.UPDATED AVIATION DISCUSSION.
.DISCUSSION...A COLD FRONT HAS SWEPT THROUGH THE FORECAST AREA...AND
THE RELATIVELY WARM PATTERN WITH HIGH SNOW LEVELS HAS ENDED. SNOW
LEVELS ARE NOW ABOUT 3500 FEET AND WILL CONTINUE TO FALL
OVERNIGHT. FAVORABLE JET DYNAMICS IS ENHANCING PRECIPITATION OVER
NORTHEAST CALIFORNIA...AND WE HAVE ISSUED A WINTER WEATHER
ADVISORY AT WSWMFR FOR SEVERAL INCHES OF SNOW EXPECTED THIS
EVENING IN LOCATIONS SUCH AS ALTURAS. THE HRRR SHOWED THIS ENHANCED
AREA OF PCPN THE BEST...AND IT SHOWS SNOW DIMINISHING THERE BY
MIDNIGHT. ELSEWHERE...SNOW IS EXPECTED TO IMPACT THE FOOTHILLS OF
THE CASCADES TONIGHT IN JACKSON AND DOUGLAS COUNTIES AND THE WSW
CONTINUES FOR THOSE AREAS INTO SATURDAY MORNING.
WESTERLY FLOW ALOFT WILL HELP BRING 3-6 MORE INCHES OF SNOW TO THE
CASCADES TONIGHT INTO TOMORROW. TRAVELERS INTO THE MOUNTAINS CAN
EXPECT SOME SNOW COVERED ROADS AND LOWER VISIBILITIES THROUGH
SATURDAY.
SATURDAY WILL FEATURE THE AFOREMENTIONED RAIN AND SNOW
SHOWERS...WITH SNOW LEVELS DIPPING TO ABOUT 2000 FEET. NAM12 OUTPUT
SUGGESTS ENOUGH INSTABILITY FOR THUNDERSTORMS FOR MUCH OF THE WEST
SIDE...GENERALLY ALONG AND WEST OF I-5.
SEE THE PREVIOUS DISCUSSION BELOW FOR MORE DETAILS ON THE SHOWERY
AND COLD CONDITIONS EXPECTED THIS WEEKEND.
&&
.AVIATION...FOR THE 30/06Z TAF CYCLE...MVFR/IFR AND NEAR TOTAL
TERRAIN OBSCURATION IN SHOWERS IS EXPECTED THROUGH THE NIGHT. THE
WORST CONDITIONS WILL LIKELY BE IN THE CASCADES AND IN MODOC COUNTY
WHERE SNOW SHOWERS WILL BRING IFR VISIBILITIES. ANOTHER WEAK
DISTURBANCE WILL BRING A MORE FOCUSED PERIOD OF SHOWERS TO THE COAST
AROUND MIDNIGHT WITH CIGS POTENTIALLY LOWERING TO MVFR AT TIMES.
SCATTERED TO WIDESPREAD SHOWERS ARE EXPECTED ON SATURDAY...MAINLY
FROM THE CASCADES WEST. ADDITIONALLY...THUNDERSTORMS ARE POSSIBLE
OVERNIGHT INTO TOMORROW OVER THE COASTAL WATERS TO AREAS JUST
INLAND. FB/SK
&&
.MARINE...UPDATED 800 PM PST FRI 29 JAN 2016...STEEP SEAS AND WEST
SWELL WILL GRADUALLY SUBSIDE OVER THE WEEKEND BUT WILL REMAIN
HAZARDOUS TO SMALL CRAFT UNTIL EARLY NEXT WEEK. HIGH PRESSURE WILL
BUILD INTO THE WATERS LATE THIS WEEKEND. WEAK LOW PRESSURE WILL
ARRIVE TUESDAY MORNING BUT WINDS SHOULD REMAIN BELOW SMALL CRAFT
ADVISORY CRITERIA. SK
&&
.PREV DISCUSSION... /ISSUED 235 PM PST FRI JAN 29 2016/
SHORT TERM...AS AN UPPER LEVEL TROUGH CENTERED TO THE NORTH MOVES
INLAND AND VERY COLD AIR ALOFT MOVES INTO THE AREA, SHOWERS WILL
SPREAD INLAND FROM THE NORTHWEST AND SNOW LEVELS WILL LOWER.
AHEAD OF THE SHOWERS, RAIN AND SNOW WILL CONTINUE OVER PORTIONS OF
SOUTHERN OREGON AND ACROSS NORTHERN CALIFORNIA LATE THIS AFTERNOON
AND THIS EVENING. SHOWERS ARE EXPECTED TO INCREASE OVER THE AREA
TODAY AND SATURDAY MORNING.
SNOW LEVELS ARE CURRENTLY AROUND 3500 TO 4000 FEET WEST OF THE
CASCADES IN SOUTHERN OREGON AND 4000 TO 6000 FEET EAST OF THE
CASCADES AND IN NORTHERN CALIFORNIA. SNOW LEVELS WILL LOWER TO
2500 FEET THIS EVENING FROM THE SOUTHERN OREGON CASCADES WESTWARD
AND BETWEEN 2500 TO 4500 FEET EAST OF THE CASCADES AND IN NORTHERN
CALIFORNIA. THEN SNOW LEVELS DROP FURTHER, LOWERING DOWN TO 2000
FEET LATE TONIGHT AND SATURDAY MORNING. LOW SNOW LEVELS COMBINED
WITH INCREASING SHOWER ACTIVITY TONIGHT AND SATURDAY MORNING WILL
BRING LIGHT TO MODERATE SNOW ACCUMULATIONS TO THE AREA, WITH
MODERATE SNOW OVER THE SOUTHERN OREGON CASCADES AND THE WESTERN
SLOPES OF THE SOUTHERN OREGON CASCADES WHERE AROUND 1 TO 4 INCHES
IS EXPECTED ABOVE 2000 FEET AND 4 TO 6 INCHES ABOVE 3000 FEET
WITH LOCALLY HIGHER AMOUNTS UP TO 10 INCHES ABOVE 5500 FEET,
ESPECIALLY IN THE CRATER LAKE AREA. LOCALLY SNOW OR A RAIN/SNOW
MIX MAY FALL DOWN TO 1500 FEET ELEVATION SATURDAY MORNING BUT
EXPECT LITTLE IF ANY ACCUMULATIONS.
SHOWERS ARE FORECAST TO CONTINUE THROUGH THE DAY SATURDAY WITH
ADDITIONAL LIGHT SNOW ACCUMULATIONS AND SNOW LEVELS AROUND 2500
TO 3000 FEET.
SATURDAY NIGHT INTO SUNDAY, COLDER CONDITIONS WILL DEVELOP AS THE
UPPER LEVEL TROUGH BECOMES CENTERED OVER THE AREA. MODELS ARE IN
GOOD AGREEMENT THAT SHOWERS WILL BE MAINLY LIMITED TO THE COASTAL
AREAS AND OVER THE COASTAL WATERS SATURDAY NIGHT AND SUNDAY. THEN
AS DAYTIME INSTABILITY INCREASES WITH THE COLD TROUGH OVERHEAD,
EXPECT SHOWERS TO INCREASE DURING THE DAY SUNDAY, MAINLY OVER THE
HIGHER TERRAIN FROM THE CASCADES WEST. SNOW LEVELS ARE FORECAST
AROUND 500 TO 1500 FEET SUNDAY MORNING RISING TO 2000 TO 2500
FEET IN THE AFTERNOON. THE FLOW ALOFT WILL BE MORE NORTHERLY AND
NOT AS MOIST. SO, SNOW ACCUMULATIONS ARE FORECAST TO REMAIN LIGHT.
MODELS SHOW DIFFERENCES IN THE AMOUNT OF SHOWER ACTIVITY AND
COVERAGE FOR SUNDAY INTO SUNDAY NIGHT THOUGH AND WILL NEED TO
MONITOR THE FORECAST DURING THIS PERIOD.
LONG TERM...MONDAY THROUGH FRIDAY...HIGH PRESSURE AND UPPER LEVEL
RIDGING WILL BEGIN TO RETURN MONDAY, AND THIS SHOULD BRING A
DRYING TREND TO THE FORECAST AREA. THE UPPER LEVEL FLOW WILL BE
FROM THE NORTHWEST THROUGH ABOUT WEDNESDAY NIGHT OR THURSDAY, AND
THIS WILL PROVIDE AN OPPORTUNITY FOR A SHORTWAVE TO TRAVERSE OVER
THE REGION TUESDAY AND TUESDAY NIGHT. THERE IS SOME DIFFERENCE
BETWEEN THE ECMWF AND GFS SOLUTION REGARDING THIS WAVE, WITH THE
GFS PRODUCING A STRONGER WAVE THAT MOVES DIRECTLY OVER SOUTHERN
OREGON, WHILE THE ECMWF SHOWS A WEAKER WAVE SLIDING BY JUST TO OUR
NORTH. WITH ENSEMBLES SHOWING A WIDE RANGE OF VARIABILITY DURING
THIS TIME, CONFIDENCE IS LOW IN EITHER SPECIFIC SOLUTION. HAVE
THEREFORE TRENDED TOWARDS A GENERAL BLEND, AND KEPT A SLIGHT
CHANCE OR CHANCE OF PRECIPITATION FROM TUESDAY INTO EARLY
WEDNESDAY MORNING. SNOW LEVELS DURING THIS SYSTEM WILL REMAIN
BELOW 3000 FEET, AND MAY EVEN APPROACH THE VALLEY FLOORS AT TIMES,
BUT AS PRECIPITATION SHOULD BE LIGHT, NO MAJOR IMPACTS ARE
EXPECTED.
AFTER ANOTHER BRIEF PERIOD OF HIGH PRESSURE AND DRIER CONDITIONS
WEDNESDAY NIGHT INTO THURSDAY MORNING, ANOTHER WAVE IS EXPECTED
THURSDAY AFTERNOON. MODELS ARE IN SURPRISINGLY GOOD AGREEMENT FOR
THIS WAVE, BUT AS THERE IS LITTLE TO INDICATE THAT THIS WOULD BE A
STRONG SYSTEM, HAVE KEPT PRECIPITATION CHANCES ON THE LOW SIDE. SNOW
LEVELS SHOULD JUMP UP TO ABOUT 5000 FEET, SO AGAIN, LITTLE IMPACT IS
EXPECTED. HIGH PRESSURE AND RIDGING WILL THEN RETURN AND REMAIN IN
CONTROL THROUGH THE END OF THE TERM. -BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 AM PST SATURDAY FOR ORZ025.
WINTER WEATHER ADVISORY UNTIL 10 AM PST SATURDAY FOR ORZ026.
CA...WINTER WEATHER ADVISORY UNTIL 11 PM PST THIS EVENING FOR
CAZ083-085.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PST SUNDAY
FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST SUNDAY
FOR PZZ370-376.
$$
NSK/BPN/FJB
AREA FORECAST DISCUSSION
NWS MEDFORD OR
814 PM PST FRI JAN 29 2016
.DISCUSSION...A COLD FRONT HAS SWEPT THROUGH THE FORECAST AREA...AND
THE RELATIVELY WARM PATTERN WITH HIGH SNOW LEVELS HAS ENDED. SNOW
LEVELS ARE NOW ABOUT 3500 FEET AND WILL CONTINUE TO FALL
OVERNIGHT. FAVORABLE JET DYNAMICS IS ENHANCING PRECIPITATION OVER
NORTHEAST CALIFORNIA...AND WE HAVE ISSUED A WINTER WEATHER
ADVISORY AT WSWMFR FOR SEVERAL INCHES OF SNOW EXPECTED THIS
EVENING IN LOCATIONS SUCH AS ALTURAS. THE HRRR SHOWED THIS
ENHANCED AREA OF PCPN THE BEST...AND IT SHOWS SNOW DIMINISHING
THERE IN BY MIDNIGHT. ELSEWHERE...SNOW IS EXPECTED TO IMPACT THE
FOOTHILLS OF THE CASCADES TONIGHT IN JACKSON AND DOUGLAS COUNTIES
AND THE WSW CONTINUES FOR THOSE AREAS INTO SATURDAY MORNING.
WESTERLY FLOW ALOFT WILL HELP BRING 3-6 MORE INCHES OF SNOW TO THE
CASCADES TONIGHT INTO TOMORROW. TRAVELERS INTO THE MOUNTAINS CAN
EXPECT SOME SNOW COVERED ROADS AND LOWER VISIBILITIES THROUGH
SATURDAY.
SATURDAY WILL FEATURE THE AFOREMENTIONED RAIN AND SNOW
SHOWERS...WITH SNOW LEVELS DIPPING TO ABOUT 2000 FEET. NAM12 OUTPUT
SUGGESTS ENOUGH INSTABILITY FOR THUNDERSTORMS FOR MUCH OF THE WEST
SIDE...GENERALLY ALONG AND WEST OF I-5.
SEE THE PREVIOUS DISCUSSION BELOW FOR MORE DETAILS ON THE SHOWERY
AND COLD CONDITIONS EXPECTED THIS WEEKEND.
&&
.AVIATION...FOR THE 30/00Z TAF CYCLE...MVFR/IFR AND NEAR TOTAL
TERRAIN OBSCURATION IN RAIN SHOWERS IS EXPECTED OVERNIGHT. SATELLITE
IMAGERY SHOWS A SMALL BREAK IN CLOUDS AT KOTH BUT WE EXPECT UPSTREAM
CLOUDS TO FILL IN LATER THIS EVENING. ANOTHER WEAK DISTURBANCE WILL
BRING LIGHT SHOWERS TO THE COAST AROUND MIDNIGHT WITH CIGS LOWERING
TO MVFR AT TIMES. TO THE EAST SNOW SHOWERS WILL MOVE THROUGH THE
KLAMATH BASIN THIS EVENING WITH CONDITIONS LOWERING TO MVFR FOR MOST
OF THE NIGHT. THERE COULD BE BRIEF IFR PERIODS IN MODERATE SNOW
SHOWERS. /FB
&&
.MARINE...UPDATED 230 PM PST FRI 29 JAN 2016...STEEP SEAS AND
WEST SWELL WILL GRADUALLY SUBSIDE OVER THE WEEKEND BUT WILL
REMAIN HAZARDOUS TO SMALL CRAFT UNTIL EARLY NEXT WEEK. HIGH
PRESSURE WILL BUILD INTO THE WATERS LATE THIS WEEKEND. WEAK LOW
PRESSURE WILL ARRIVE TUESDAY MORNING BUT WINDS SHOULD REMAIN BELOW
SMALL CRAFT ADVISORY CRITERIA. /FB
&&
.PREV DISCUSSION... /ISSUED 235 PM PST FRI JAN 29 2016/
SHORT TERM...AS AN UPPER LEVEL TROUGH CENTERED TO THE NORTH MOVES
INLAND AND VERY COLD AIR ALOFT MOVES INTO THE AREA, SHOWERS WILL
SPREAD INLAND FROM THE NORTHWEST AND SNOW LEVELS WILL LOWER.
AHEAD OF THE SHOWERS, RAIN AND SNOW WILL CONTINUE OVER PORTIONS OF
SOUTHERN OREGON AND ACROSS NORTHERN CALIFORNIA LATE THIS AFTERNOON
AND THIS EVENING. SHOWERS ARE EXPECTED TO INCREASE OVER THE AREA
TODAY AND SATURDAY MORNING.
SNOW LEVELS ARE CURRENTLY AROUND 3500 TO 4000 FEET WEST OF THE
CASCADES IN SOUTHERN OREGON AND 4000 TO 6000 FEET EAST OF THE
CASCADES AND IN NORTHERN CALIFORNIA. SNOW LEVELS WILL LOWER TO
2500 FEET THIS EVENING FROM THE SOUTHERN OREGON CASCADES WESTWARD
AND BETWEEN 2500 TO 4500 FEET EAST OF THE CASCADES AND IN NORTHERN
CALIFORNIA. THEN SNOW LEVELS DROP FURTHER, LOWERING DOWN TO 2000
FEET LATE TONIGHT AND SATURDAY MORNING. LOW SNOW LEVELS COMBINED
WITH INCREASING SHOWER ACTIVITY TONIGHT AND SATURDAY MORNING WILL
BRING LIGHT TO MODERATE SNOW ACCUMULATIONS TO THE AREA, WITH
MODERATE SNOW OVER THE SOUTHERN OREGON CASCADES AND THE WESTERN
SLOPES OF THE SOUTHERN OREGON CASCADES WHERE AROUND 1 TO 4 INCHES
IS EXPECTED ABOVE 2000 FEET AND 4 TO 6 INCHES ABOVE 3000 FEET
WITH LOCALLY HIGHER AMOUNTS UP TO 10 INCHES ABOVE 5500 FEET,
ESPECIALLY IN THE CRATER LAKE AREA. LOCALLY SNOW OR A RAIN/SNOW
MIX MAY FALL DOWN TO 1500 FEET ELEVATION SATURDAY MORNING BUT
EXPECT LITTLE IF ANY ACCUMULATIONS.
SHOWERS ARE FORECAST TO CONTINUE THROUGH THE DAY SATURDAY WITH
ADDITIONAL LIGHT SNOW ACCUMULATIONS AND SNOW LEVELS AROUND 2500
TO 3000 FEET.
SATURDAY NIGHT INTO SUNDAY, COLDER CONDITIONS WILL DEVELOP AS THE
UPPER LEVEL TROUGH BECOMES CENTERED OVER THE AREA. MODELS ARE IN
GOOD AGREEMENT THAT SHOWERS WILL BE MAINLY LIMITED TO THE COASTAL
AREAS AND OVER THE COASTAL WATERS SATURDAY NIGHT AND SUNDAY. THEN
AS DAYTIME INSTABILITY INCREASES WITH THE COLD TROUGH OVERHEAD,
EXPECT SHOWERS TO INCREASE DURING THE DAY SUNDAY, MAINLY OVER THE
HIGHER TERRAIN FROM THE CASCADES WEST. SNOW LEVELS ARE FORECAST
AROUND 500 TO 1500 FEET SUNDAY MORNING RISING TO 2000 TO 2500
FEET IN THE AFTERNOON. THE FLOW ALOFT WILL BE MORE NORTHERLY AND
NOT AS MOIST. SO, SNOW ACCUMULATIONS ARE FORECAST TO REMAIN LIGHT.
MODELS SHOW DIFFERENCES IN THE AMOUNT OF SHOWER ACTIVITY AND
COVERAGE FOR SUNDAY INTO SUNDAY NIGHT THOUGH AND WILL NEED TO
MONITOR THE FORECAST DURING THIS PERIOD.
LONG TERM...MONDAY THROUGH FRIDAY...HIGH PRESSURE AND UPPER LEVEL
RIDGING WILL BEGIN TO RETURN MONDAY, AND THIS SHOULD BRING A
DRYING TREND TO THE FORECAST AREA. THE UPPER LEVEL FLOW WILL BE
FROM THE NORTHWEST THROUGH ABOUT WEDNESDAY NIGHT OR THURSDAY, AND
THIS WILL PROVIDE AN OPPORTUNITY FOR A SHORTWAVE TO TRAVERSE OVER
THE REGION TUESDAY AND TUESDAY NIGHT. THERE IS SOME DIFFERENCE
BETWEEN THE ECMWF AND GFS SOLUTION REGARDING THIS WAVE, WITH THE
GFS PRODUCING A STRONGER WAVE THAT MOVES DIRECTLY OVER SOUTHERN
OREGON, WHILE THE ECMWF SHOWS A WEAKER WAVE SLIDING BY JUST TO OUR
NORTH. WITH ENSEMBLES SHOWING A WIDE RANGE OF VARIABILITY DURING
THIS TIME, CONFIDENCE IS LOW IN EITHER SPECIFIC SOLUTION. HAVE
THEREFORE TRENDED TOWARDS A GENERAL BLEND, AND KEPT A SLIGHT
CHANCE OR CHANCE OF PRECIPITATION FROM TUESDAY INTO EARLY
WEDNESDAY MORNING. SNOW LEVELS DURING THIS SYSTEM WILL REMAIN
BELOW 3000 FEET, AND MAY EVEN APPROACH THE VALLEY FLOORS AT TIMES,
BUT AS PRECIPITATION SHOULD BE LIGHT, NO MAJOR IMPACTS ARE
EXPECTED.
AFTER ANOTHER BRIEF PERIOD OF HIGH PRESSURE AND DRIER CONDITIONS
WEDNESDAY NIGHT INTO THURSDAY MORNING, ANOTHER WAVE IS EXPECTED
THURSDAY AFTERNOON. MODELS ARE IN SURPRISINGLY GOOD AGREEMENT FOR
THIS WAVE, BUT AS THERE IS LITTLE TO INDICATE THAT THIS WOULD BE A
STRONG SYSTEM, HAVE KEPT PRECIPITATION CHANCES ON THE LOW SIDE. SNOW
LEVELS SHOULD JUMP UP TO ABOUT 5000 FEET, SO AGAIN, LITTLE IMPACT IS
EXPECTED. HIGH PRESSURE AND RIDGING WILL THEN RETURN AND REMAIN IN
CONTROL THROUGH THE END OF THE TERM. -BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 AM PST SATURDAY FOR ORZ025.
WINTER WEATHER ADVISORY UNTIL 10 AM PST SATURDAY FOR ORZ026.
CA...WINTER WEATHER ADVISORY UNTIL 11 PM PST THIS EVENING FOR
CAZ083-085.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PST SUNDAY
FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST SUNDAY
FOR PZZ370-376.
$$
NSK/BPN/FJB
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
934 PM CST SUN JAN 31 2016
.UPDATE...
FORECAST FOR TONIGHT IS MOSTLY ON TRACK. ONLY ADJUSTMENTS WERE
MADE TO THE WEATHER GRIDS AND THE HOURLY GRIDS TO RE-TREND THEM
BASED ON CURRENT OBSERVATIONS. THE RECENT RUNS OF THE HRRR AS WELL
AS THE 00Z RUN OF THE NAM MODEL BRING FOG INTO THE I-35 CORRIDOR
BY MORNING SO DID EXPAND MENTION OF PATCHY FOG. ALSO ADDED AREAS
OF FOG TO THE COASTAL PLAINS. WHILE STATIONS ALONG THE TEXAS COAST
ARE ALREADY REPORTING VISIBILITY 1 MILE OR LESS...THE INLAND OBSERVING
STATION FROM VICTORIA TO LA GRANGE HAVE ALREADY DROPPED TO 3 TO 5
MILES.
THE OTHER BIG ADDITION TO THE EVENING UPDATE WAS THE ISSUANCE OF A
FIRE WEATHER WATCH FOR FOUR COUNTIES ALONG THE RIO GRANDE PLAINS
AND WESTERN EDWARDS PLATEAU. WINDS WILL BE GUSTY TO 15 TO 20 MPH
AHEAD OF THE APPROACHING FRONT MONDAY AFTERNOON. RELATIVE
HUMIDITY VALUES WILL BOTTOM OUT IN THE TEENS TO CREATE A FEW
HOURS OF CRITICAL FIRE WEATHER IN VAL VERDE...KINNEY...MAVERICK AND
EDWARDS COUNTIES. FUEL MOISTURE IS THE BIG QUESTION FOR THESE
WESTERN AREAS...BUT THE LAST SIGNIFICANT RAINS THIS AREA
EXPERIENCED WERE BACK IN EARLY JANUARY. FOR THIS REASON WENT AHEAD
AND ISSUED THE FIRE WEATHER WATCH. SUBSEQUENT SHIFTS WILL EXAMINE
THE TRENDS AND DETERMINE WHETHER A RED FLAG WARNING WILL BE
NEEDED. FIRE WEATHER CONCERNS WILL CONTINUE INTO THE DAY ON
TUESDAY ONCE THE FRONT MOVES THROUGH. A FEW OF THE RIO GRANDE
PLAINS AND EDWARDS PLATEAU COUNTIES...EDWARDS...REAL... VAL
VERDE...KERR AND DIMMIT ARE CURRENTLY UNDER COUNTY WIDE BURN
BANS.
&&
.PREV DISCUSSION... /ISSUED 614 PM CST SUN JAN 31 2016/
AVIATION...
/00Z TAFS/
VFR CONDITIONS ARE EXPECTED THROUGH 07Z MONDAY FOR THE I-35
TERMINALS. KDRT SHOULD REMAIN VFR THROUGH THE FORECAST PERIOD.
MVFR/IFR CONDITIONS ARE EXPECTED OVERNIGHT INTO MONDAY MORNING FOR
THE I-35 SITES AS PATCHY FOG AND STRATUS CLOUDS FORM ALONG AND
EAST OF INTERSTATE 35. ONCE AGAIN...BOTH GFS LAMP AND MOS GUIDANCE
SUGGEST SEVERAL HOURS OF LIFR CONDITIONS FOR THE I-35 AIRPORTS
FROM 11Z TO 16Z MONDAY. BELIEVE THESE MODELS ARE OVER DOING LOW
VBSYS FOR THAT PERIOD WITH SIMILAR CONDITIONS EXPECTED AS EARLIER
THIS MORNING. CAN NOT RULE AN HOUR OR TWO OF LIFR AROUND KAUS FOR
THE 12Z TO 13Z TIME FRAME...HOWEVER IFR CONDITIONS ARE EXPECTED TO
BE TO MAIN FLIGHT CONDITIONS FOR MONDAY MORNING TIL 15Z.
VFR CONDITIONS RETURN TO THE I-35 SITES AFTER 15Z MONDAY AND
REMAIN THROUGH THE FORECAST PERIOD. BREEZY CONDITIONS ARE EXPECTED
ON MONDAY AHEAD OF A COLD FRONT. SOUTHERLY WINDS OF 1O TO 20 KNOTS
ARE EXPECTED WITH GUSTS UP TO 30 KNOTS. IN THE WAKE OF THE
FRONT...WINDS WILL SHIFT TO THE NORTHWEST BY MIDNIGHT TUESDAY FOR
KSAT AND KSSF AND 07 TUESDAY FOR KAUS. WIND SHIFT TO THE NW WILL
OCCUR AROUND 01Z TUESDAY FOR KDRT.
PREV DISCUSSION... /ISSUED 324 PM CST SUN JAN 31 2016/
SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...
THIS AFTERNOON...A DRY LINE SPANNED FROM EAGLE PASS TO HONDO TO
KILLEEN RESULTING IN DRY GUSTY WINDS OUT OF THE WEST AND
RELATIVELY LIGHT WINDS EAST OF THE I35 CORRIDOR AND COASTAL
PLAINS. DEWPOINTS ON THE PLATEAU WERE IN THE 20S AND AS HIGH AS 60
IN VICTORIA. HIGHS WERE IN THE UPPER 70S TO MID 80S WITH CLEAR
SKIES ACROSS THE REGION.
A VERY SIMILAR FORECAST TONIGHT COMPARED TO YESTERDAY WITH
POTENTIAL FOG DEVELOPMENT ON THE MOIST SIDE OF THE DRY LINE AND
CLOUD COVER IN THE MORNING...PERHAPS A BIT LESS COVERAGE THAN THIS
MORNING.
TOMORROW WILL BE THE LAST DAY WITH WELL ABOVE NORMAL TEMPERATURES.
OVERALL THE FORECAST HAS NOT CHANGED SUBSTANTIALLY AS EXPECTATIONS
ARE STILL FOR HIGHS IN THE MID 80S FOR MANY AREAS AND GUSTY WINDS
IN THE AFTERNOON HOURS. MOS GUIDANCE INCREASES THE WIND FIELDS
SUBSTANTIALLY LATE MORNING AND AROUND THE NOONTIME HOUR. WITH A
PRE FRONTAL SURFACE LOW AHEAD OF THE APPROACHING FRONTAL
SYSTEM...THE PGF WILL TIGHTEN AS THE LOW PASSES TO THE NORTH AND
BRING 15-25 MPH WINDS GUSTING TO 30 MPH.
CONCERNING FIRE WEATHER CONDITIONS...IT WAS DECIDED NOT TO ISSUE A
FIRE WEATHER WATCH FOR ANY OF OUR COUNTIES DUE TO THE FACT THAT
NO LOCATION IS FORECAST TO RECEIVE ALL THREE NECESSARY CRITERIA
FOR A RFW. WHILE LOCATIONS IN NORTHERN EDWARDS AND VAL VERDE AND
ALONG THE RIO GRANDE WILL EXPERIENCE THE WINDS AND MIN RH CRITERIA
OF 20 PERCENT OR BELOW...THE DISQUALIFYING FACTOR IS THE MOISTURE
CONTENT OF THE FUELS STILL NOT BEING DRY ENOUGH. WHEREAS IN THE
HILL COUNTRY...FUELS ARE A CATEGORY DRIER AND SHOULD SEE WINDS
OVER 20 MPH...BUT RH VALUES PROBABLY WONT QUITE REACH THE
CRITICAL 20 PERCENT MARK. THUS...THE FORECAST OF NEAR CRITICAL WAS
MAINTAINED FOR THESE AREAS.
LONG TERM (TUESDAY THROUGH SUNDAY)...
THE AFOREMENTIONED STRONG COLD FRONT CONTINUES TO BE PROGGED TO
PUSH INTO THE CWA LATE MONDAY NIGHT AND EARLY TUESDAY MORNING.
WITH STRONG HIGH PRESSURE BEHIND THE FRONT...WIND ADVISORY LEVEL
WINDS WILL BE POSSIBLE BY LATE MORNING AND THROUGH AT LEAST THE
EARLY AFTERNOON. IT WILL ALSO PLUNGE RH VALUES DOWN TO BELOW 20
PERCENT FOR WEST OF THE I35 CORRIDOR AND STILL BELOW 30 PERCENT
FARTHER EAST.
THIS SHOULD RESULT IN THE MOST SIGNIFICANT FIRE WEATHER THREAT OF
THE LAST FEW DAYS. WITH MULTIPLE DAYS OF IDEAL FUEL DRYING
CONDITIONS...AND THE PROSPECT OF CRITICAL WINDS AND RH
VALUES...CRITICAL FIRE WEATHER CONDITIONS APPEAR TO BE LIKELY FOR
THE WESTERN HALF OF THE CWA. DID WANT TO HOLD OFF ON A WATCH THIS
SHIFT MOSTLY DUE TO THE DESIRE TO EVALUATE THE OBSERVED FUELS
ANALYSIS FOR TODAY...LATER THIS EVENING. THAT INFORMATION SHOULD
BE ABLE TO PROVIDE A BETTER IDEA OF THE SPATIAL EXTENT THE
POSSIBLE WATCH WOULD COVER...IF CONDITIONS CONTINUE TO WARRANT THE
NEED FOR THE PRODUCT.
BEYOND TUESDAY HOWEVER...MUCH COOLER TEMPERATURES ARE EXPECTED
WHICH WILL END THE FIRE WEATHER THREAT AS RH VALUES RECOVER. OUR
NEXT POTENTIAL SYSTEM APPEARS TO BE SATURDAY WITH A DEEP DIVING
UPPER LOW...HOWEVER ECMWF OUTCOMES PRODUCE SIGNIFICANT QPF AND GFS
IS FULLY DRY. THIS TYPE OF MODEL DISCREPANCY IS AT BEST SUSPECT SO
FOR NOW...WILL WAIT FOR A BIT BETTER AGREEMENT BEFORE ADDRESSING
THIS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 85 50 79 53 70 / 0 0 0 10 -
AUSTIN BERGSTROM INTL AIRPORT 80 45 78 52 70 / 0 0 0 10 -
NEW BRAUNFELS MUNI AIRPORT 81 45 82 52 72 / 0 0 0 10 10
BURNET MUNI AIRPORT 82 45 78 47 66 / 0 0 0 10 -
DEL RIO INTL AIRPORT 88 45 87 48 69 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 83 46 77 49 69 / 0 0 0 10 -
HONDO MUNI AIRPORT 86 40 84 50 72 / 0 0 0 - -
SAN MARCOS MUNI AIRPORT 81 46 79 52 70 / 0 0 0 10 10
LA GRANGE - FAYETTE REGIONAL 81 50 77 55 70 / - 0 0 20 20
SAN ANTONIO INTL AIRPORT 83 48 81 53 72 / 0 0 0 10 -
STINSON MUNI AIRPORT 84 44 84 54 72 / 0 0 0 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM 1 PM CST TO 6 PM CST MONDAY AFTERNOON FOR
THE FOLLOWING COUNTIES: VAL VERDE...KINNEY...EDWARDS...MAVERICK.
&&
$$
MESOSCALE/AVIATION...17
SYNOPTIC/GRIDS...TREADWAY
PUBLIC SERVICE/DATA COLLECTION...TREADWAY
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
950 PM EST SUN JAN 31 2016
.SYNOPSIS...
A MILD SOUTHWEST FLOW WILL CONTINUE THROUGH MONDAY MORNING. BY
MONDAY AFTERNOON...A WEAK COLD FRONT WILL CROSS OVERHEAD TO
PROVIDE A CHANCE OF SHOWERS...BEFORE LIFTING BACK NORTH AS A WARM
FRONT ON TUESDAY NIGHT. MORE WIDESPREAD RAIN SHOULD ARRIVE FROM A
STRONGER COLD FRONT ON WEDNESDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 940 PM EDT SUNDAY...
AS EXPECTED A WIDE VARIETY OF TEMPERATURES TONIGHT BASED ON
ELEVATION. TYPICAL LOWER ELEVATION COOL SPOTS ARE ALREADY DOWN
INTO THE UPPER 30S...MEANWHILE THE HIGHER ELEVATIONS ARE STILL
HOLDING IN THE UPPER 40S TO LOWER 50S AT THIS HOUR MAKING FOR A
TRICKY TEMPERATURE FORECAST TONIGHT. LATEST HRRR RUN BRINGS PRECIP
TO OUR WESTERN DOORSTEP AROUND 16Z MONDAY MORNING WHICH ALIGNS
WELL WITH THE PREVIOUS FORECAST SO NO CHANGES WERE MADE THERE.
AS OF 340 PM EST SUNDAY...
A SOUTHWEST FLOW FROM THE WESTERN PERIPHERY OF HIGH PRESSURE
LOCATED WELL OFFSHORE...CONTINUES TO PUMP WARM AIR OVER THE MID
ATLANTIC. PLENTY OF SOLAR HEATING OCCURRED TODAY UNDER MOSTLY
SUNNY SKIES WITH JUST SOME SCATTERED CIRRUS CLOUDS. IN
RESPONSE...TEMPERATURES HAVE REBOUNDED NICELY FROM THE CHILLY
START THIS MORNING...SO HIGHS WILL REACH THE UPPER 50S TO THE
UPPER 60S. IT IS A NICE AFTERNOON TO GET OUTSIDE AND ENJOY THE
SUNSHINE AND WARMTH FOR THE LAST DAY OF JANUARY...BECAUSE IT WILL
NOT LAST LONG WHEN FEBRUARY BEGINS.
BY TONIGHT...CLOUDS WILL INCREASE FROM THE WEST...AS A WEAK COLD
FRONT APPROACHES THE APPALACHIAN MOUNTAINS. A DECENT LOW LEVEL
JET FROM THE SOUTHWEST AT 40 KT...SHOULD BRING MORE MOISTURE.
WIND GUSTS UP TO 30 KT ARE POSSIBLE ALONG THE HIGHEST TERRAIN.
THE WARM AIR ADVECTION...THICKENING CLOUD COVER...AND AMPLE MIXING
WOULD SUGGEST THAT LOWS WILL NOT DROP MUCH TONIGHT. HOWEVER...A
LITTLE SNOW COVER STILL REMAINS WEST OF THE BLUE RIDGE...AND THE
MIXING WILL NOT BE AS STRONG TO THE EAST. THUS...LOWS TONIGHT ARE
TRICKY DUE TO THESE COMPETING FACTORS...BUT IT SEEMS THAT THE
UPPER 30S TO THE UPPER 40S IS THE BEST RANGE TO UTILIZE.
RAIN SHOWERS SHOULD ARRIVE ON MONDAY MORNING ALONG THE WESTERN
SLOPES...AND SPREAD EASTWARD DURING THE DAY. POPS WERE INCREASED
TO HIGHLIGHT THE INCREASING CONFIDENCE OF RAIN IN THE LATEST
MODEL SOLUTIONS. QPF WILL ONLY REACH A TENTH TO A THIRD OF AN INCH
WEST OF THE BLUE RIDGE...AND LOWER AMOUNTS SHOULD FALL TO THE
EAST. THE MODELS HINT THAT SOME OF THE MOISTURE COULD CROSS OVER
THE BLUE RIDGE...BUT IT MAY STRUGGLE TO REACH SOUTHSIDE VIRGINIA
AND THE NORTH CAROLINA PIEDMONT. CLOUDY SKIES AND SHOWERS SHOULD
KEEP HIGHS IN THE UPPER 40S TO THE MID 50S WEST OF THE BLUE RIDGE.
IN THE PIEDMONT...LOWER CHANCES OF RAIN AND PEEKS OF SUNSHINE
COULD PUSH HIGHS INTO THE UPPER 50S TO THE MID 60S.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 407 PM EST SUNDAY...
SURFACE COLD FRONT WILL DRIFT THROUGH THE FORECAST AREA MONDAY
EVENING...WINDS BECOMING NORTHERLY...THEN TENDING NORTHEASTERLY
OVERNIGHT. TEMPERATURES WILL TAKE A TUMBLE INTO THE 40S...POSSIBLY
REACHING THE UPPER 30S ACROSS THE NORTHERN CWA BY DAYBREAK
TUESDAY...BUT NOTHING BELOW FREEZING. IN SPITE OF THE LINGERING LOW
LEVEL CLOUD COVER THERE WILL BE LITTLE OR NO UPPER LEVEL SUPPORT FOR
PRECIP PRODUCTION...SO ANY THREAT FOR RAIN MONDAY NIGHT IS LESS THAN
50 PERCENT.
FOR TUESDAY...FRONT WILL BE STALLED ACROSS THE CAROLINAS LEAVING
MOST OF OUR CWA WEDGED ON THE COOL SIDE OF THE FRONT WITH SHALLOW
AREA OF HIGH PRESSURE EXTENDING NORTHEAST ALONG THE EAST SIDE OF THE
APPALACHIANS INTO NEW ENGLAND. A PERSISTENT NORTHEAST TO EASTERLY
SORT OF WIND WILL KEEP LOW LEVEL MOISTURE/CLOUDS BANKED UP AGAINST
THE EAST SIDE OF THE MOUNTAINS THROUGHOUT THE DAY...TEMPERATURES
RISING VERY LITTLE. ON THE FLIP SIDE...WEST SIDE...OF THE
APPALACHIAN DIVIDE...THERE SHOULD BE VERY LITTLE INFLUENCE FROM THE
COOL WEDGE...SO TEMPERATURES ACROSS THE TENNESSEE VALLEY SHOULD WARM
BACK INTO THE 50S/60S.
WEDNESDAY WILL BE THE MOST ACTIVE WEATHER DAY THIS WEEK AS A STRONG
STRONG STORM SYSTEM MOVES FROM THE UPPER MIDWEST INTO THE GREAT
LAKES...ITS ASSOCIATED COLD FRONT SWEEPING EAST AND THROUGH OUR
FORECAST AREA. STRONG SOUTHWEST FLOW AHEAD OF THE FRONT WILL BRING
DEEPER MOISTURE BACK INTO THE REGION AS EARLY AS TUESDAY NIGHT...THE
SOUTHWEST WINDS PUSHING THE OLD STALLED FRONT TO OUR SOUTH BACK
NORTH AS A WARM FRONT. CONVERGENCE OVER THE OLD FRONTAL BOUNDARY IN
ADDITION TO INCREASING UPSLOPE WIND FLOW ON THE SOUTHEAST SIDE OF
THE APPALACHIANS WILL RESULT IN THE DEVELOPMENT OF RAIN/DRIZZLE
ACROSS THE AREA TUESDAY NIGHT...INCREASING IN INTENSITY TOWARD
DAYBREAK WEDNESDAY. BOTH TEMPERATURES AND DEWPOINTS WILL ON THE
RISE TUESDAY NIGHT...THE COOLEST TEMPERATURES OCCURRING BEFORE
MIDNIGHT...THEN STEADILY RISING. RAIN COVERAGE AND INTENSITY WILL
CONTINUE TO INCREASE UNTIL THE PASSAGE OF THE STRONG COLD
FRONT...MID-DAY WEDNESDAY.
TYPICAL WITH THESE SORT OF SYSTEMS...AND ESPECIALLY ON SATURATED
GROUND FROM OUR EXISTING SNOW MELT...CONCERNS OF RAINFALL...WIND...
AND THUNDERSTORMS WOULD BE CONSIDERED. HOWEVER...INDICATIONS ARE
THAT THE MAIN DYNAMICS WILL TRACK WELL NORTH OF THE REGION...THE
SYSTEM MOVING RATHER QUICKLY THROUGH THE REGION...AND INSTABILITY IS
MARGINAL AT BEST. AS A RESULT...QPF SHOULD GENERALLY BE LESS THAN
ONE INCH...AND WHEN COMBINED WITH SNOW MELT SHOULD NOT POSE ANY
SIGNIFICANT RUNOFF PROBLEMS. THAT SAID...A WIND ADVISORY MAY BE
WARRANTED FOR PARTS OF THE FORECAST AREA...BUT DO NOT ANTICIPATE
OTHER HEADLINES ATTM.
THE RAIN IS EXPECTED TO COME TO AN END FROM WEST TO EAST WEDNESDAY
AFTERNOON. IN SPITE OF THE SUBSIDENCE IN THE WAKE OF THE
FRONT...THE EASTWARD PROGRESS OF THE FRONT IS EXPECTED TO SLOW AS IT
ENCOUNTERS AN UPPER RIDGE OFF THE COAST. MODELS ALSO HINT THAT A
WAVE OF LOW PRESSURE WILL FORM ALONG THE FRONT THURSDAY WHICH
WOULD...AT THE VERY LEAST RESULT IN LINGERING CLOUDINESS ACROSS THE
FORECAST AREA.
TEMPERATURES WEDNESDAY WILL SPIKE JUST PRIOR TO FROPA...POSSIBLY
REACHING THE 60S ACROSS THE PIEDMONT. ONCE THE FRONT MOVES
THROUGH...TEMPERATURES WILL THEN TREND COLDER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 407 PM EST SUNDAY...
A TREND TOWARD MUCH COLDER CONDITIONS AND GENERALLY DRY WEATHER
EXPECTED FOR THE WEEKEND. HOWEVER...MODELS STILL SOMEWHAT
TROUBLESOME ABOUT LOW PRESSURE DEVELOPING ALONG THE REMNANT FRONTAL
BOUNDARY/BAROCLINIC ZONE ALONG THE SOUTHEAST U.S. COAST. MODEL
CONSENSUS IS TO KEEP THIS PRECIPITATION SOUTH AND EAST OF OUR REGION
AND THIS PACKAGE CONTINUES TO ADVERTISE A DRY FORECAST FOR THE RNK
CWA IN THE EXTENDED PERIODS. THIS AGREES WITH WPC THINKING ATTM.
THE EASTERN U.S. TROUGH IS DESTINED TO REMAIN IN PLACE INTO THE
WEEKEND AND AT LEAST THE FIRST HALF OF THE FOLLOWING WEEK AS SEVERAL
ALBERTA CLIPPERS TRACK THROUGH THE EASTERN CONUS HELPING TO
REINFORCE AND DEEPEN THE TROUGH. SEVERAL SURGES OF CANADIAN/ARCTIC
AIR ARE PROGGED TO SPREAD SOUTHEAST...THE INTENSITY OF WHICH VARIES
ACCORDING TO WHATEVER MODEL YOU CHOOSE TO LOOK AT. NONETHELESS...A
TREND TOWARD NORMAL AND EVEN BELOW NORMAL TEMPERATURES APPEARS
LIKELY. QUESTION THEN BECOMES WILL THERE BE ANY SHORT WAVE ENERGY
TO ROUND THE BASE OF THE UPPER TROUGH TO SPAWN SOMETHING THAT
WOULD PRODUCE MORE THAN JUST THE TYPICAL UPSLOPE SNOW SHOWERS.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
AS OF 655 PM EST SUNDAY...
CLOUDS WILL THICKEN AND LOWER OVERNIGHT IN ADVANCE OF A COLD
FRONT THAT WILL REACH THE APPALACHIANS MONDAY MORNING. HIGH
CONFIDENCE THAT CEILINGS WILL REMAIN VFR THROUGH 06Z/1AM OVER THE
MOUNTAINS AND 09Z/4AM IN THE FOOTHILLS AND PIEDMONT. NAM/GFS/RAP
AND 18Z LOCAL WRF ALL HAVE RAIN REACHING KBLF AND KLWB AROUND
12Z/7AM MONDAY MORNING. CEILINGS WILL BE MVFR FOR MUCH OF THE DAY
ALONG AND WEST OF THE BLUE RIDGE AS THE RAIN ADVANCES SLOWLY EAST
ACROSS THE MOUNTAINS. DURING THE AFTERNOON...KDAN AND KLYH WILL
HAVE A BETTER PROBABILITY OF RAIN AND MVFR CEILINGS. CONFIDENCE IS
MEDIUM TO HIGH ON THE ARRIVAL TIME OF THE RAIN.
HAVE ADDED LOW LEVEL WIND SHEAR TO THE TAFS OVERNIGHT WITH A LOW
LEVEL WSW JET THAT HAS SPEEDS CLOSE TO 50 KNOTS. THE FRONT WILL BE
CLOSE TO THE VIRGINIA/NORTH CAROLINA BORDER BY THE 00Z/7PM END OF
TAF PERIOD. LOW TO MEDIUM CONFIDENCE THAT THE BOUNDARY WILL STILL
BE NORTH OF KDAN AT 00Z.
EXTENDED DISCUSSION...
HIGH PRESSURE SHOULD BRIEFLY FOLLOW FOR MONDAY NIGHT WITH A
SURFACE BASED WEDGE STRENGTHENING. BY TUESDAY...ABUNDANT LOW LEVEL
MOISTURE AND OVERRUNNING WARM AIR ADVECTION WILL RESULT IN
WIDESPREAD IFR TO MVFR CONDITIONS. A PERIOD OF MODERATE RAIN WILL
ARRIVE WITH THE PASSAGE OF A STRONG FRONT ON WEDNESDAY...AGAIN
ALONG WITH IFR/MVFR CEILINGS AND VISIBILITIES. HIGH PRESSURE WILL
RETURN ON THURSDAY...AND PROVIDE COLDER AIR ALONG WITH A RECOVERY
TO VFR CONDITIONS THROUGH FRIDAY.
&&
.EQUIPMENT...
KFCX RADAR IS DOWN UNTIL FURTHER NOTICE. TECHNICIANS WILL
INVESTIGATE EARLY MONDAY MORNING.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PW
NEAR TERM...CF/PW
SHORT TERM...PM
LONG TERM...PM
AVIATION...AMS/PW
EQUIPMENT...CF
AREA FORECAST DISCUSSION
NWS PORTLAND OR
902 AM PST SAT JAN 30 2016
.SYNOPSIS...COOL AND UNSETTLED WITH SHOWERY WEATHER THROUGH WED...
WITH SNOW LEVELS BELOW PASSES OF THE CASCADES. BUT WILL SEE RETURN OF
RAIN AND HIGHER SNOW LEVELS WITH A MORE ORGANIZED FRONT TOWARDS THU
AND FRI.
&&
.SHORT TERM...TODAY THROUGH MONDAY...NOT MUCH CHANGE THIS AM.
STEADY COLD UNSTABLE AIR ALOFT RIDING WESTERLY WINDS INTO THE REGION.
THIS WILL KEEP SHOWERS TODAY. WITH SNOW LEVELS HOLDING NEAR 2000
FEET...WILL SEE SMALL HAIL IN SOME OF THE HEAVIER SHOWERS. EMBEDDED
SHORTWAVES WILL ENHANCE SHOWER ACTIVITY THIS AFTERNOON AND EVENING
ESPECIALLY N OF A LINCOLN CITY TO SANTIAM PASS LINE. THE AIR MASS IS
UNSTABLE ENOUGH FOR SOME ISOLATED THUNDERSTORMS OVER THE WATERS THIS
WEEKEND. THUNDERSTORMS MAY ALSO EXTEND INLAND WITH DAYTIME INSOLATION
TODAY AND AGAIN SUNDAY.
CASCADES WILL SEE DECENT SNOW ACCUMULATIONS IN THE CASCADES TODAY
AS SNOW LEVELS LOWER TO AROUND 1500 TO 2000 FEET. THE ONSHORE FLOW
EASES SOME THIS AFTERNOON AND TONIGHT SO SNOWFALL RATES WILL DECREASE
AS WELL. SNOW SHOWERS WILL CONTINUE INTO SUNDAY BUT ACCUMULATIONS
ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA. WITH THE LOW SNOW
LEVELS THE COAST RANGE AND CASCADE FOOTHILLS WILL ALSO SEE SOME SNOW.
HIGHER PASSES CROSSING THE COAST RANGE MAY SEE LIGHT ACCUMULATIONS
TONIGHT AND SUNDAY.
THERE IS STILL A CHANCE OF SHOWERS WITH SNOW IN THE MOUNTAINS MONDAY
UNDER NORTHWESTERLY FLOW ALOFT AND AT LOW LEVELS. SNOW LEVELS WILL
REMAIN AROUND 1500 FT.
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH FRIDAY...A WEAK SHORTWAVE TROUGH LOOKS TO
QUICKLY MOVE ACROSS THE PAC NW TUESDAY MAINTAINING OUR SHOWERY
PATTERN. SNOW LEVELS WILL HOVER AROUND 2000 FT SO SOME LIGHT
ACCUMULATIONS IN THE CASCADES...FOOTHILLS...AND COAST RANGE APPEAR
LIKELY. UPPER LEVEL RIDGING LOOKS TO MOVE INTO THE REGION LATE
TUESDAY AND COULD BRING A BRIEF PERIOD OF DRY WEATHER THROUGH
WEDNESDAY SO HAVE LOWERED POPS ACROSS THE FORECAST AREA TO AROUND 20
PERCENT OR LESS. MODELS CONTINUE TO SHOW A FRONT APPROACHING THE
COAST NEXT WEEK BUT HAVE SLOWED IT DOWN A BIT. THE FRONT IS NOW
EXPECTED TO MOVE ACROSS THE REGION THURSDAY...WITH SNOW LEVELS
RISING TO AROUND 4000 FT LATE THURSDAY. UPPER LEVEL RIDGING LOOKS TO
BUILD BEHIND THE FRONT LATE THURSDAY AND COULD GIVE US A FEW DAYS OF
DRY WEATHER LATE NEXT WEEK. EXPECT SEASONAL TEMPS THROUGH THE
FORECAST PERIOD. /64
&&
.AVIATION...SHOWERY AND UNSTABLE ONSHORE FLOW CONTINUES TODAY AND
TONIGHT. MVFR CIGS FORMED EARLIER THIS MORNING OVER THE INTERIOR
LOWLANDS FROM AROUND KSLE AND AREAS NORTHWARD. EXPECT THAT THIS
MVFR DECK WILL BREAK UP BY AROUND 18Z AS A BAND OF SHOWERS MOVES
THROUGH. THEN EXPECT PREDOMINANTLY VFR CONDITIONS THROUGH
TONIGHT...WITH OCCASIONAL MVFR POSSIBLE IN HEAVIER SHOWERS.
THERE IS A SLIGHT CHANCE OF THUNDERSTORMS AGAIN TODAY WITH SMALL
HAIL POSSIBLE AS WELL. CONFIDENCE IN TIMING OR LOCATION OF
THUNDERSTORMS IS NOT HIGH ENOUGH TO INCLUDE IN THE TAFS.
KPDX AND APPROACHES...AN MVFR DECK SHOULD BREAK UP BY AROUND 18Z.
THEN EXPECT MAINLY VFR CONDITIONS WITH OCCASIONAL SHOWERS THROUGH
TONIGHT. BRIEF PERIODS OF MVFR POSSIBLE IN HEAVIER SHOWERS. THERE
IS ALSO A SLIGHT CHANCE FOR A THUNDERSTORM THROUGH THE DAY. PYLE
&&
.MARINE...WINDS GENERALLY 10 TO 15 KT OUT OF THE WEST THROUGH THIS
EVENING. A WEAK SURFACE LOW CURRENTLY ALONG THE B.C. COAST WILL
WEAKEN FURTHER STILL AND WORK SLOWLY SOUTH THROUGH WESTERN
WASHINGTON AND OREGON TONIGHT AND SUN. THIS MAY BRING A PERIOD OF
20 TO 25 KT NW WINDS FROM EARLY SUN MORNING THROUGH THE AFTERNOON.
ISOLATED THUNDERSTORMS WILL REMAIN A POSSIBILITY THROUGH
SUNDAY...WHICH ANY STORMS BRINGING THE POTENTIAL FOR BRIEF WIND
GUSTS TO 30 KT. A DECAYING FRONT WILL MOVE THROUGH THE WATERS MON
NIGHT INTO TUE MORNING. THIS SYSTEM IS LOOKING WEAKER AND WEAKER
IN THE MODELS AND MAY DO LITTLE OTHER THAN SHIFT THE WINDS BACK TO
THE SOUTH. A STRONGER FRONT IS EXPECTED WED NIGHT INTO THU. THIS
SYSTEM WILL LIKELY BRING AT LEAST SMALL CRAFT ADVISORY
WINDS...WITH THE POTENTIAL FOR GALES.
SEAS REMAIN AROUND 12 TO 14 RANGE TODAY WITH THE PRIMARY SWELL OUT
OF THE WEST. THEY WILL CONTINUE TO GRADUALLY SUBSIDE THROUGH THE
WEEKEND...FINALLY DROPPING BELOW 10 FT LATE SUN OR EARLY MON. SEAS
THEN REMAIN BELOW 10 FT FOR THE FIRST HALF OF NEXT WEEK. ANOTHER
LONG PERIOD WESTERLY SWELL IS MODELED TO ARRIVE DURING THE SECOND
HALF OF NEXT WEEK...LIKELY PUSHING SEAS BACK INTO MID TEENS. PYLE
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR CASCADES IN
LANE COUNTY-NORTHERN OREGON CASCADES.
WA...WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR SOUTH
WASHINGTON CASCADES.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 AM PST SUNDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60
NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL MIDNIGHT
PST TONIGHT.
&&
$$
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
National Weather Service Spokane WA
354 AM PST SAT JAN 30 2016
.SYNOPSIS...
An upper level trough will settle over the region today and
linger through Monday. This will result in seasonal temperatures
with a chance of snow showers. Expect a short dry period through
mid-week then a more organized system approach again toward next
Thursday.
&&
.DISCUSSION...
Today through Sunday night...The ridge of high pressure has been
replaced by a long wave trough over the region. This will put the
region into more of a westerly flow and effectively cut the region
off from the deep Pacific moisture tap that has been over the
Pacific Northwest for most of the week. But that doesn`t mean
conditions will be totally dry. The cold core will track across
the forecast area today. This will destabilize the atmosphere. In
addition model guidance has been pretty consistent showing a
series of weak short wave disturbances moving through the area
today through Sunday. Enough moisture will linger for scattered
rain and snow showers both days. The best chance for showers will
be on the lee side of the Cascades and of course in the
orographically favored Panhandle mountains and the Blue mountains.
However, in this type of a pattern just about anywhere could pop
an intense, short lived shower. Precipitation would be mainly as
snow with rain/snow mix for the lower elevations and possibly some
graupel. The NAM and HRRR models have been picking up on a
particularly robust wave this morning across the southeast zones,
from the Camas Prairie north to around Pullman and Avery. As such
pops were bumped up in this area. A fast couple of inches of
snowfall could be possible with these showers. Pretty tough to
pinpoint just exactly where these will form so no highlights are
expected and we will handle this with Nowcasts and social media as
best we can. Temperatures should be within a degree or two of
seasonal normals. Southwest winds across the southeast zones will
remain slightly elevated today with sustained winds 10-15 mph and
gusts around 25 mph through most of the day.
The upper level trough will shift east Saturday night through
Monday as a high amplitude ridge tracks from about 150W to near
the coast. This will shift the flow into an even drier northwest-
north flow. Isolated to scattered showers will linger near the
Cascade crest, the northeast mountains with light snow
accumulations at times. Northwest-northerly flow supports a better
chance for showers for the Panhandle mountains and this is an
excellent set up for the Blues and Camas Prairie. While showers
will remain in the forecast, we expect less moisture to work with
and the train of weak disturbances will get cut-off. I wouldn`t be
surprised if a few spots pick up an inch or two of snow. But this
will be isolated and widely scattered. Tobin
Monday through Tuesday night...Shortwave energy will continue to
keep a chance of snow showers across the forecast area through
Tuesday but mainly confined to the Cascade crest and the eastern
third of the forecast area. The northerly overland trajectory will
keep any snowfall accumulations rather light. By Tuesday night the
offshore ridge axis will start to migrate east. This will relegate
any lingering precipitation to the Idaho panhandle. Daytime
temperatures will be in the 30s with low 40s for the southernmost
valleys. Overnight lows will be on a cooling trend as northerly flow
keeps bringing colder air in from the north.
Wednesday through Friday...The east Pacific ridge will be pushed
inland by an approaching trough of low pressure. The mainly dry
weather pattern for Wednesday will become more unsettled as the
trough moves through the Inland Northwest Thursday. As warmer air
aloft pushes into the region from the south Thursday morning there
is a threat of freezing rain for the lower basin and possibly into
the Wenatchee area as well. Thursday looks like the best bet for
some light to moderate snowfall accumulations for much of the
forecast area. Beyond Thursday, model solutions diverge with the
ECMWF allowing the ridge to quickly build back over the region while
the GFS keeps a more unsettled trough pattern over us. /Kelch
&&
.AVIATION...
12Z TAFS: An upper level trough has moved into the area overnight
and will linger through at least Sunday. This will allow the
atmosphere to destabilize and support snow showers across the
region...mainly though the afternoon and early evening. A slightly
stronger wave looks to move through the southeast zones and
may increase the intensity of the showers near KLWS/KPUW through
00z this afternoon. Otherwise showers will be isolated to
scattered. Southwest winds and lingering boundary level moisture
will allow stratus formation for the KCOE/KSFF/KGEG corridor with
conditions MVFR/IFR. Near KPUW/KLWS VFR/MVFR conditions for
localized stratus and the potential for heavier showers. Lastly
the southwest winds have backed off from yesterday...but still
expect winds 10-15 kts with gusts 20-25kts for KPUW and KGEG.
Tobin
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 36 27 34 26 34 24 / 20 20 20 20 20 20
Coeur d`Alene 35 27 34 27 33 26 / 30 30 40 20 20 40
Pullman 38 28 35 28 34 26 / 60 20 40 20 40 30
Lewiston 44 32 42 31 39 30 / 60 20 20 20 40 20
Colville 34 27 33 26 33 23 / 20 20 20 20 10 30
Sandpoint 34 28 33 27 32 27 / 30 30 40 30 20 40
Kellogg 33 27 31 25 31 24 / 70 40 50 30 50 50
Moses Lake 41 27 38 26 37 25 / 10 10 10 10 10 10
Wenatchee 38 29 36 27 36 27 / 10 10 10 10 10 10
Omak 34 25 32 22 32 21 / 10 20 20 10 10 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS PORTLAND OR
305 AM PST SAT JAN 30 2016
.SYNOPSIS...COOL AND SOMEWHAT UNSTABLE ONSHORE FLOW WILL CONTINUE TO
SPREAD SHOWERS WITH SNOW IN THE MOUNTAINS ACROSS SOUTHWEST WASHINGTON
AND NORTHWEST OREGON...WITH A FEW THUNDERSTORMS NEAR THE COAST
SPREADING INLAND IN THE AFTERNOONS AND EARLY EVENINGS.
THE SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE
WEEKEND...THOUGH THE ONSHORE FLOW WILL WEAKEN SOME LATER SATURDAY
THROUGH SUNDAY. SNOW LEVELS WILL FALL TO BETWEEN 1500 AND 2500 FEET
THIS WEEKEND...POSSIBLY A LITTLE LOWER IN ANY HEAVIER SHOWERS. WHILE
THE LOW LEVEL FLOW WILL BECOME MORE NORTHWESTERLY EARLY NEXT
WEEK...SOME COOL SHOWERS WILL CONTINUE AS WEAK DISTURBANCES MOVE
THROUGH MONDAY AND TUESDAY. THE NEXT ORGANIZED FRONT IS EXPECTED
AROUND THURSDAY OF NEXT WEEK.
&&
.SHORT TERM...TODAY THROUGH MONDAY...SHOWERS CONTINUE TO STREAM
ACROSS THE AREA THIS MORNING WITH THE SNOW LEVEL DOWN TO AROUND
2000-2500 FEET. INFRARED SATELLITE SHOWS A LARGE AREA OF COLD AIR
CUMULUS EXTENDING WEST OF THE WA/OR COAST. THIS WILL BE THE SOURCE OF
THE SHOWERS THROUGH THE WEEKEND. EMBEDDED SHORTWAVES WILL ENHANCE
SHOWER ACTIVITY THIS AFTERNOON AND EVENING ESPECIALLY OVER THE
NORTHERN ZONES. THE AIR MASS IS UNSTABLE ENOUGH FOR SOME ISOLATED
THUNDERSTORMS OVER THE WATERS THIS WEEKEND. THUNDERSTORMS MAY ALSO
EXTEND INLAND WITH DAYTIME INSOLATION TODAY AND SUNDAY.
CASCADES WILL SEE DECENT SNOW ACCUMULATIONS IN THE CASCADES TODAY
AS SNOW LEVELS LOWER TO AROUND 1500 TO 2000 FEET. THE ONSHORE FLOW
EASES SOME THIS AFTERNOON AND TONIGHT SO SNOWFALL RATES WILL DECREASE
AS WELL. SNOW SHOWERS WILL CONTINUE INTO SUNDAY BUT ACCUMULATIONS
ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA. WITH THE LOW SNOW
LEVELS THE COAST RANGE AND CASCADE FOOTHILLS WILL ALSO SEE SOME SNOW.
HIGHER PASSES CROSSING THE COAST RANGE MAY SEE LIGHT ACCUMULATIONS
TONIGHT AND SUNDAY.
THERE IS STILL A CHANCE OF SHOWERS WITH SNOW IN THE MOUNTAINS MONDAY
UNDER NORTHWESTERLY FLOW ALOFT AND AT LOW LEVELS. SNOW LEVELS WILL
REMAIN AROUND 1500 FT. /MH
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH FRIDAY...A WEAK SHORTWAVE TROUGH LOOKS TO
QUICKLY MOVE ACROSS THE PAC NW TUESDAY MAINTAINING OUR SHOWERY
PATTERN. SNOW LEVELS WILL HOVER AROUND 2000 FT SO SOME LIGHT
ACCUMULATIONS IN THE CASCADES...FOOTHILLS...AND COAST RANGE APPEAR
LIKELY. UPPER LEVEL RIDGING LOOKS TO MOVE INTO THE REGION LATE
TUESDAY AND COULD BRING A BRIEF PERIOD OF DRY WEATHER THROUGH
WEDNESDAY SO HAVE LOWERED POPS ACROSS THE FORECAST AREA TO AROUND 20
PERCENT OR LESS. MODELS CONTINUE TO SHOW A FRONT APPROACHING THE
COAST NEXT WEEK BUT HAVE SLOWED IT DOWN A BIT. THE FRONT IS NOW
EXPECTED TO MOVE ACROSS THE REGION THURSDAY...WITH SNOW LEVELS
RISING TO AROUND 4000 FT LATE THURSDAY. UPPER LEVEL RIDGING LOOKS TO
BUILD BEHIND THE FRONT LATE THURSDAY AND COULD GIVE US A FEW DAYS OF
DRY WEATHER LATE NEXT WEEK. EXPECT SEASONAL TEMPS THROUGH THE
FORECAST PERIOD. /64
&&
.AVIATION...OVER THE NEXT 24 HOURS WEATHER PATTERN STAYS PRETTY
MUCH THE SAME. UNSTABLE ONSHORE FLOW WILL CONTINUE TO BRING
SCATTERED SHOWERS AND KEEP CONDITIONS AT TERMINALS PREDOMINANTLY
VFR. OCCASIONALLY CIGS AND VIS WILL DROP TO MVFR WITH HEAVIER
SHOWERS. CHANCE OF THUNDERSTORMS OVER THE INTERIOR SATURDAY MID-
DAY WITH SMALL HAIL POSSIBLE. CONFIDENCE IN TIMING OR LOCATION OF
THUNDERSTORMS IS NOT HIGH ENOUGH TO INCLUDE IN THE TAFS.
KPDX AND APPROACHES...SCATTERED SHOWERS FOR NEXT 24 HRS.
PREDOMINANTLY VFR CONDITIONS WITH CIGS AND VIS OCCASIONALLY
DROPPING TO MVFR IN HEAVIER SHOWERS. THUNDER POSSIBLE AROUND
MIDDAY SATURDAY. BOWEN
&&
.MARINE...WINDS REMAIN JUST ABOVE 20 KT SO WILL LET THE SMALL
CRAFT ADVISORY FOR WINDS RUN ITS COURSE THROUGH 12Z. WINDS
GENERALLY COMING DOWN THOUGH...SO DO NOT THINK IT WILL NEED TO BE
EXTENDED. ONCE WINDS DROP BELOW 20 KT...SHOULD STAY DOWN UNTIL AT
LEAST EARLY SUNDAY MORNING. HOWEVER ISOLATED THUNDERSTORMS ARE
POSSIBLE TONIGHT THROUGH SUNDAY...WHICH COULD PRODUCE INFREQUENT
WIND GUSTS UP TO 30 KT.
MUCH UNCERTAINTY STILL WITH THE LOW PRESSURE SYSTEM ON SUNDAY.
THOUGH IT WILL BE RELATIVELY WEAK...THERE IS THE POSSIBILITY THAT
IT COULD CAUSE GUSTY WINDS ACROSS THE LOCAL WATERS. WORST CASE IT
WILL BRING WINDS GUSTING TO 25 TO 30 KT SUNDAY MID-DAY OR EVENING
OUT OF THE NORTHWEST. IF THE CIRCULATION MOVES INLAND TO OUR
NORTH...WINDS SHOULD STAY BELOW 20 KT ALL DAY SUNDAY. HIGH
PRESSURE BUILDS OVER THE WATERS EARLY NEXT WEEK FOR GENERALLY
BENIGN CONDITIONS WITH SEAS FALLING BELOW 10 FT LATE MONDAY.
BEYOND THAT...THE NEXT SYSTEM ISN`T UNTIL A STRONGER FRONTAL
SYSTEM APPROACHES OUR WATERS LATE WEDNESDAY INTO THURSDAY. BOWEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR
CASCADES IN LANE COUNTY-NORTHERN OREGON CASCADES.
WA...WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR SOUTH
WASHINGTON CASCADES.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 AM PST EARLY THIS
MORNING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 AM PST SUNDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT
60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
MIDNIGHT PST TONIGHT.
&&
$$
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
National Weather Service Spokane WA
229 AM PST SAT JAN 30 2016
.SYNOPSIS...
An upper level trough will settle over the region today and
linger through Monday. This will result in seasonal temperatures
with a chance of snow showers. Expect a short dry period through
mid-week then a more organized system approach again toward next
Thursday.
&&
.DISCUSSION...
Today through Sunday night...The ridge of high pressure has been
replaced by a long wave trough over the region. This will put the
region into more of a westerly flow and effectively cut the region
off from the deep Pacific moisture tap that has been over the
Pacific Northwest for most of the week. But that doesn`t mean
conditions will be totally dry. The cold core will track across
the forecast area today. This will destabilize the atmosphere. In
addition model guidance has been pretty consistent showing a
series of weak short wave disturbances moving through the area
today through Sunday. Enough moisture will linger for scattered
rain and snow showers both days. The best chance for showers will
be on the lee side of the Cascades and of course in the
orographically favored Panhandle mountains and the Blue mountains.
However, in this type of a pattern just about anywhere could pop
an intense, short lived shower. Precipitation would be mainly as
snow with rain/snow mix for the lower elevations and possibly some
graupel. The NAM and HRRR models have been picking up on a
particularly robust wave this morning across the southeast zones,
from the Camas Prairie north to around Pullman and Avery. As such
pops were bumped up in this area. A fast couple of inches of
snowfall could be possible with these showers. Pretty tough to
pinpoint just exactly where these will form so no highlights are
expected and we will handle this with Nowcasts and social media as
best we can. Temperatures should be within a degree or two of
seasonal normals. Southwest winds across the southeast zones will
remain slightly elevated today with sustained winds 10-15 mph and
gusts around 25 mph through most of the day.
The upper level trough will shift east Saturday night through
Monday as a high amplitude ridge tracks from about 150W to near
the coast. This will shift the flow into an even drier northwest-
north flow. Isolated to scattered showers will linger near the
Cascade crest, the northeast mountains with light snow
accumulations at times. Northwest-northerly flow supports a better
chance for showers for the Panhandle mountains and this is an
excellent set up for the Blues and Camas Prairie. While showers
will remain in the forecast, we expect less moisture to work with
and the train of weak disturbances will get cut-off. I wouldn`t be
surprised if a few spots pick up an inch or two of snow. But this
will be isolated and widely scattered. Tobin
Monday through Tuesday night...Shortwave energy will continue to
keep a chance of snow showers across the forecast area through
Tuesday but mainly confined to the Cascade crest and the eastern
third of the forecast area. The northerly overland trajectory will
keep any snowfall accumulations rather light. By Tuesday night the
offshore ridge axis will start to migrate east. This will relegate
any lingering precipitation to the Idaho panhandle. Daytime
temperatures will be in the 30s with low 40s for the southernmost
valleys. Overnight lows will be on a cooling trend as northerly flow
keeps bringing colder air in from the north.
Wednesday through Friday...The east Pacific ridge will be pushed
inland by an approaching trough of low pressure. The mainly dry
weather pattern for Wednesday will become more unsettled as the
trough moves through the Inland Northwest Thursday. As warmer air
aloft pushes into the region from the south Thursday morning there
is a threat of freezing rain for the lower basin and possibly into
the Wenatchee area as well. Thursday looks like the best bet for
some light to moderate snowfall accumulations for much of the
forecast area. Beyond Thursday, model solutions diverge with the
ECMWF allowing the ridge to quickly build back over the region while
the GFS keeps a more unsettled trough pattern over us. /Kelch
&&
.AVIATION...
06Z TAFS: Winds have decreased across most of the region. Expect
some stratus to develop btwn 08-10Z for eastern TAF sites. Latest
NAM and HRRR is showing some -shsn developing aft 10Z for eastern
TAF locations. HRRR has been waffling a bit btwn runs, but have
kept it in the TAF. More confident about KPUW than other sites.
The -shsn potential ends btwn 15 and 18Z with clouds generally
lifting and decreasing through the afternoon. The potential exists
for stratus to set up in the Columbia Basin and Wenatchee area as
well. Am more confident about KEAT than KMWH. The stratus will
linger around through the morning and then break up in the aftn.
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 36 27 34 26 34 24 / 20 20 20 20 20 20
Coeur d`Alene 35 27 34 27 33 26 / 30 30 40 20 20 40
Pullman 38 28 35 28 34 26 / 60 20 40 20 40 30
Lewiston 44 32 42 31 39 30 / 60 20 20 20 40 20
Colville 34 27 33 26 33 23 / 20 20 20 20 10 30
Sandpoint 34 28 33 27 32 27 / 30 30 40 30 20 40
Kellogg 33 27 31 25 31 24 / 70 40 50 30 50 50
Moses Lake 41 27 38 26 37 25 / 10 10 10 10 10 10
Wenatchee 38 29 36 27 36 27 / 10 10 10 10 10 10
Omak 34 25 32 22 32 21 / 10 20 20 10 10 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS SEATTLE WA
900 PM PST FRI JAN 29 2016
.SYNOPSIS...AN UPPER TROUGH OVER THE PACIFIC NORTHWEST WILL MOVE
SOUTH TO CALIFORNIA OVER THE WEEKEND. THE AIR IS COOL AND UNSTABLE
WITH SHOWERS OVER WESTERN WASHINGTON. THE WEATHER PATTERN WILL BE
COOL AND SHOWERY INTO EARLY NEXT WEEK.
&&
.SHORT TERM...CONVECTIVE CLOUDS STRETCH WELL OFFSHORE ON SATELLITE
IMAGERY THIS EVENING. THERE HAVE BEEN A FEW TSTMS WITH SMALL HAIL
BUT THEY SEEM TO HAVE BEEN FEW AND FAR BETWEEN CONSIDERING THE COLD
AIR ALOFT WHICH WAS -33C AT 500MB ON THE KUIL SOUNDING THIS
AFTERNOON. A RATHER LARGE PATCH OF COLD AIR ALOFT WILL BE SINKING
SOUTH OVER THE REGION THROUGH THE WEEKEND SO THE SNOW LEVEL WILL BE
ON THE LOW SIDE. PUGET SOUND CONVERGENCE ZONE ACTIVITY MIGHT OCCUR
AT TIMES INTO SUNDAY AND MONDAY AS DISTURBANCES MOVE THROUGH THE
AREA IN THE COLD AIR ALOFT. THE 00Z UW MM5NAM HAD SOME DECENT SNOW
IN THE OLYMPICS ON SUNDAY...THEN MOSTLY IN THE CENTRAL CASCADES MON
AND TUE.
.LONG TERM...A TRANSITORY UPPER LEVEL RIDGE WILL MOVE OVER THE AREA
WED AND WED NITE. A WEAKENING FRONT WILL REACH THE AREA
THURSDAY...POSSIBLY FOLLOWED BY STRONGER RIDGING TOWARD THE END OF
NEXT WEEK.
&&
.AVIATION...AN UPPER LEVEL TROUGH WILL LINGER OVER THE REGION
THROUGH THE WEEKEND. MODERATE WLY FLOW ALOFT TONIGHT WILL BECOME
LIGHT SW FLOW ALOFT SATURDAY AND SATURDAY NIGHT. WEAKLY UNSTABLE
WITH ISOLATED THUNDERSTORMS UNTIL MIDNIGHT. THE CHANCE OF TS AT ANY
TERMINAL IS LESS THAN 20 PERCENT SO WILL LEAVE OUT OF 06Z TAFS WHEN
ISSUED. MOIST AT ALL LEVELS. SHOWERS AND A POSSIBLE PUGET SOUND
CONVERGENCE ZONE COULD AFFECT THE KPAE TERMINAL AT TIMES THROUGH
SATURDAY MORNING.
KSEA...CIGS WILL BE SOMEWHAT VARIABLE TONIGHT AS SHOWERS PASS THE
TERMINALS AT TIMES. IT NOW APPEARS IT WILL REMAIN UNSTABLE ENOUGH
WITH SOME MIXING TO PREVENT ANY LOWER IFR CIGS FROM FORMING. MOST
LIKELY...VFR CONDITIONS WILL PERSIST THROUGH SATURDAY BUT A COULD
HOURS OF MVFR CANNOT BE RULES OUT LATE TONIGHT/EARLY SATURDAY
MORNING IF THE AIR MASS STABILIZES TEMPORARILY.
&&
.MARINE...A SURFACE TROUGH WILL MAINTAIN ONSHORE FLOW THROUGH
SATURDAY BUT GRADUALLY WEAKENING. LOW END SMALL CRAFT WINDS ARE
STILL POSSIBLE OVER MOST THE WATERS TONIGHT BUT WINDS WILL WANE BY
MORNING. SEAS WILL REMAIN NEAR 15 FEET SO A SMALL CRAFT FOR
HAZARDOUS SEAS COAST AND WEST ENTRANCE WILL GO INTO AFFECT AT 6 AM
WITH THE SMALL CRAFT FOR WINDS ENDS. HIGH PRESSURE WILL BRIEFLY
BUILD OVER THE WATERS ON MONDAY. A WEAKENING FRONTAL SYSTEM WILL
REACH THE AREA ON TUESDAY. DTM
&&
.HYDROLOGY...THE SKOKOMISH RIVER WILL CONTINUE RECEDING...AND IS
FORECAST TO FALL BELOW FLOOD STAGE LATE TONIGHT OR EARLY SATURDAY.
AFTER THAT...FLOODING IS NOT EXPECTED THROUGH NEXT WEEK.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WINTER WEATHER ADVISORY UNTIL 3 PM PST SATURDAY FOR CASCADES OF
PIERCE AND LEWIS COUNTIES-CASCADES OF SNOHOMISH AND KING
COUNTIES-CASCADES OF WHATCOM AND SKAGIT COUNTIES.
HIGH SURF ADVISORY UNTIL 8 AM PST SATURDAY FOR CENTRAL COAST.
PZ...SMALL CRAFT ADVISORY UNTIL 6 AM PST SATURDAY FOR COASTAL WATERS.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 6 AM TO 6 PM PST
SATURDAY FOR THE COASTAL WATERS AND WEST ENTRANCE TO THE STRAIT.
SMALL CRAFT ADVISORY THROUGH 6 AM PST SATURDAY FOR THE ENTIRE
STRAIT OF JUAN DE FUCA...PUGET SOUND...AND NORTHERN INLAND WATERS.
SMALL CRAFT ADVISORY FOR ROUGH BAR THROUGH SATURDAY EVENING FOR
GRAYS HARBOR BAR.
&&
$$
WWW.WEATHER.GOV/SEATTLE
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
Area Forecast Discussion
National Weather Service Spokane WA
819 PM PST FRI JAN 29 2016
.SYNOPSIS...
A strong low pressure area will track through the northeast corner
of Washington into extreme north Idaho this evening spreading
widespread snow, with most of the significant accumulations
occurring over the mountains. The low will also deliver windy
conditions to southeast Washington and north central Idaho this
evening. The low will be followed by a trough of low pressure
which will settle into the region Saturday and lingers through
Monday, delivering seasonal temperatures with a chance of snow
showers. A more organized system approach again toward next
Thursday.
&&
.DISCUSSION...
The surface low that brought winds to southeast WA and the
southern Id Panhandle has shifted east into Western MT this
evening. The winds have subsided and cancelled the advisory early.
Elevated winds will continue there this evening and decrease to
about 10 mph overnight and then pick up again Saturday late
morning or early afternoon. These winds will only last a few hours
and will be below advisory criteria. Both the NAM and HRRR are
showing some energy moving trough the Palouse in the westerly
flow overnight. They are suggesting some snow sticking to the
ground and will be updating the forecast tonight for that.
Generally will expect less than an inch of snowfall.
Light snow showers will continue across extreme NE WA and north
ID this evening and then decrease through the night.
The winter weather advisory for the Cascades will end at 10pm,
but snow is expected to continue through the night along the
crest. Models are showing a convergence zone setting up right
along the crest north of Stevens Pass, but south of Lake Chelan in
Chelan County. They suggest the band of moderate to heavy snow
will continue through the night and Saturday morning before
tapering off in the afternoon. Will be updating forecast to
account for this snowfall. /Nisbet
&&
.AVIATION...
00Z TAFS: Tough aviation forecasts for most sites as strong low
pressure drifts from current position in NE WA near GEG and into
NW MT early this evening. The departing low will shift the main
threat of precipitation away from any of the forecast sites, with
the main problem then trending toward what to do about residual
cloud cover. The latest visible satellite imagery was showing
rapid clearing over the SE corner of WA and the southern Columbia
Basin so the forecasts for PUW LWS MWH and EAT will likely
feature VFR conditions for a while this evening. However there is
a fair chance that stratus redevelops sometime overnight. Just not
sure how high the clouds will be or when they will reform. Then
there is the question how long with the clouds persist into
Saturday. MOS guidance is all over the place so confidence is very
low. Another issue is the winds. LWS and PUW will see the
strongest winds with speeds of 20-30kts and gusts to 30-40kts
expected through 02Z. The most difficult forecasts will be the
GEG-SFF-COE ones. Low clouds will likely persist through most of
the night with IFR conditions, however there is clearing about 60
miles SW of GEG. We suspect some of that clearing could move into
GEG between 02-03z and perhaps to COE shortly thereafter. However
we aren`t confident that any of this clearing will persist long
as moist upslope sw flow behind recent precipitation is notorious
for reforming stratus in a hurry. The question would be would it
be the MVFR or IFR category. Whatever forms will likely persist
through most of the forecast period. fx/LN
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 29 37 25 35 25 34 / 10 20 20 20 20 20
Coeur d`Alene 31 36 27 35 26 33 / 20 40 20 40 20 20
Pullman 32 38 28 36 25 35 / 70 40 20 20 20 40
Lewiston 36 45 33 42 31 40 / 40 40 20 20 20 40
Colville 30 35 27 35 25 33 / 20 20 10 30 20 20
Sandpoint 32 35 28 34 27 32 / 80 40 30 50 30 20
Kellogg 30 33 26 32 25 31 / 90 50 40 50 30 40
Moses Lake 30 42 27 39 26 38 / 0 10 10 10 10 10
Wenatchee 31 39 29 38 28 36 / 20 10 10 10 10 10
Omak 26 35 24 34 23 32 / 0 10 10 10 10 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Winter Weather Advisory until 10 PM PST this evening for East
Slopes Northern Cascades.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
345 PM CST SAT JAN 30 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 344 PM CST SAT JAN 30 2016
AT 3 PM...WATER VAPOR IMAGERY SHOWS A FAIRLY STRONG AND COMPACT
SHORT WAVE TROUGH MOVING EAST ACROSS NORTH DAKOTA. WITH THE AIR
MASS FAIRLY DRY BELOW 7K FEET...ONLY A FEW SPRINKLES ARE
ASSOCIATED WITH THIS FEATURE. THE 30.12Z MODELS ARE IN GOOD
AGREEMENT THAT THIS FEATURE WILL MOVE EAST ACROSS CENTRAL
MINNESOTA AND NORTHERN WISCONSIN THIS EVENING. THERE WILL BE
ENOUGH OF A NORTHWEST PUSH IN THE WAKE OF THIS SYSTEM TO BRING A
WEAK COLD FRONT INTO THE AREA. WE CAN ALREADY SEE SOME EVIDENCE OF
THIS FRONT OVER SOUTHWEST AND CENTRAL WISCONSIN. THE MODELS ARE IN
GOOD AGREEMENT THAT STRONG 900 TO 700 MB FRONTOGENESIS WILL
DEVELOP ALONG AND NORTH OF THE INTERSTATE 90 CORRIDOR. IN ADDITION
TO THIS...THE AREA IS LOCATED IN THE RIGHT ENTRANCE REGION OF A
110 KNOT JET THIS EVENING AND EARLY OVERNIGHT. SOUNDINGS CONTINUE
TO SHOW THAT THERE CONTINUES TO BE A 2 TO 5F WARM LAYER ALOFT
SOUTH OF INTERSTATE 94. THIS WILL RESULT IN RAIN IN THIS AREA. AT
THIS TIME...IT LOOKS LIKE THE TEMPERATURES SHOULD REMAIN JUST
ABOVE FREEZING THROUGH TONIGHT AND SUNDAY MORNING. HOWEVER IF THE
TEMPERATURES HAPPEN TO FALL TO FREEZING...WE MAY HAVE TO CONTEND
WITH SOME LIGHT FREEZING RAIN IN SOUTHEAST MINNESOTA AND NORTH
CENTRAL WISCONSIN. ALSO IF THERE IS ENOUGH EVAPORATIVE COOLING
NORTH OF INTERSTATE 94...THERE MAY BE SOME LIGHT SNOW. WITH THE
MODELS BEING IN FAIRLY GOOD AGREEMENT THAT THIS SYSTEM WILL BE
EXITING THE AREA DURING THE MORNING...LOWERED THE PRECIPITATION
CHANCES DURING THE EARLY AFTERNOON...AND KEPT MOST AREAS DRY
DURING THE MID AND LATE AFTERNOON.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 344 PM CST SAT JAN 30 2016
THE MAIN CONCERN DURING THIS TIME PERIOD CONTINUES TO BE FROM
TUESDAY THROUGH WEDNESDAY. THE OPERATIONAL GFS...GEM...AND ECMWF
CONTINUE TO SUGGEST THAT THE SURFACE LOW WILL LIKELY TRACK FROM
KANSAS CITY TO CHICAGO AND THEN NORTHEAST INTO NORTHERN LOWER
MICHIGAN AND EASTERN UPPER MICHIGAN. WITH THIS TRACK...SOUNDINGS
CONTINUE TO SUGGEST THAT THE AREA WILL BE COLD ENOUGH ALOFT FOR
PRETTY MUCH THE ENTIRE AREA TO SEE ONLY SNOW FROM THIS SYSTEM. THE
LONE EXCEPTION MAYBE IN FAR SOUTHWEST WISCONSIN WHERE THE BOUNDARY
LAYER TEMPERATURES MAY WARM ENOUGH THAT THERE COULD BE A BRIEF MIX
OF RAIN OR A WINTRY MIX. WHILE THERE IS GOOD AGREEMENT AMONGST
MOST OF THE MAJOR OPERATIONAL MODELS ON THE TRACK OF THIS
SYSTEM...THE NAM AND MANY MEMBERS OF CANADIAN ENSEMBLE HAVE A
FURTHER SOUTHEAST TRACK. MANY OF THE EASTERN AND SOUTHERN
SOLUTIONS HAVE A MUCH WEAKER WAVE COMING OUT OF THE SOUTHWEST
UNITED STATES. ANOTHER ISSUE THAT WE MIGHT HAVE TO CONTEND WITH IS
HOW MUCH THE CONVECTION ALONG THE COLD FRONT MIGHT LIMIT SOME OF THE
MOISTURE IN THE DEFORMATION AREA. THE LAST 5 GFS RUNS OF COBB DATA
HAS BEEN CONSISTENTLY IN THE 10 TO 15 INCH RANGE. MEANWHILE IN
ROCHESTER...IT WAS AROUND 15 INCHES ON FRIDAY...BUT IN THE LAST 2
MODEL RUNS IT HAS DECREASED INTO THE 6 TO 8 INCH RANGE. THE REASON
FOR THE DIFFERENCE IN THAT THE WARM CONVEYOR BELT HAS SHIFTED JUST
A BIT FURTHER EAST AND THIS IS ALLOWING THE DRIER AIR ASSOCIATED
WITH THE COLD CONVEYOR BELT TO MOVE INTO THE AREA FASTER. USING
THE CURRENT PRECIPITATION TOTALS AND SNOW TO LIQUID RATIOS IN THE
10-15 TO 1 RANGE...THE PRELIMINARY SNOW TOTALS IN THE FORECAST
GRIDS FOR TUESDAY ARE 2 TO 5 INCHES NORTH OF INTERSTATE 94 AND 5
TO 10 INCHES ACROSS THE REMAINDER OF THE FORECAST AREA. AN
ADDITIONAL 2 TO 4 INCHES LOOK POSSIBLE FOR TUESDAY NIGHT. THIS
WOULD RESULT IN A TOTAL OF 8 TO 13 INCHES OF SNOW. THESE SNOW
TOTALS WILL BE HIGHLY DEPENDENT UPON THE FINAL TRACK OF THIS
SYSTEM...SO THEY WILL LIKELY FLUCTUATE BETWEEN NOW AND TUESDAY.
SINCE THIS SYSTEM IS NOT ONSHORE YET AND NOT BEING WELL SAMPLED
BY THE UPPER AIR NETWORK...THERE IS STILL THE POTENTIAL THAT THIS
TRACK COULD STILL SHIFT. DUE TO THIS...THE CONSENSUS WAS TO WAIT
ON ISSUING A WINTER STORM WATCH FOR NOW.
IN ADDITION TO THE SNOW...THERE IS CONCERN ABOUT THE STRONG
SURFACE PRESSURE GRADIENT THAT DEVELOPS ACROSS SOUTHERN MINNESOTA
AND NORTHEAST IOWA. THIS COULD RESULT IN SUSTAINED WIND OF 20 TO
30 MPH AND GUSTS UP TO 35 MPH. THIS COULD RESULT IN CONSIDERABLE
BLOWING AND DRIFTING FROM LATE TUESDAY AFTERNOON INTO WEDNESDAY
MORNING.
THOSE WITH TRAVEL PLANS FROM THE CENTRAL PLAINS INTO THE NORTHERN
GREAT LAKES EARLY NEXT WEEK SHOULD CONTINUE TO MONITOR FUTURE
FORECASTS CLOSELY THROUGH TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1116 AM CST SAT JAN 30 2016
WATCHING A SHORT WAVE TROUGH MOVING INTO THE WESTERN DAKOTAS LATE
THIS MORNING. WARM AIR ADVECTION ZONE AHEAD OF THIS WAVE IS
CAUSING SOME RADAR RETURNS OVER SOUTHWEST MINNESOTA...BUT SO
FAR...ONLY MID LEVEL CLOUDS ARE BEING REPORTED FROM THIS AREA. THE
30.16Z HRRR SUGGESTS THIS AREA OF RETURNS WILL CONTINUE TO
STRENGTHEN THROUGH THE AFTERNOON WITH SOME LIGHT RAIN OR SPRINKLES
POSSIBLE AT KRST BEFORE 00Z. LOOKING AT THE RAP BUFKIT SOUNDINGS
FOR THIS TIME FRAME...THERE IS STILL A LOT OF LOW LEVEL DRY AIR IN
PLACE AND WOULD NOT EXPECT MUCH MORE THAN SPRINKLES IF IT DOES
MOVE IN THIS AFTERNOON. OTHERWISE...THE TIMING FOR THE LIGHT RAIN
TO MOVE IN FROM OTHER 30.12Z MODELS IS EARLY THIS EVENING. THE
FORCING FROM THIS WAVE DOES NOT LOOK TO BE VERY STRONG SO
EXPECTING LITTLE OR NO VISIBILITY RESTRICTIONS TO OCCUR WITH
MAINLY VFR CEILINGS. THE EXCEPTION TO THAT MAY BE LATE TONIGHT AT
KLSE IF THE COLUMN CAN COOL ENOUGH TO SUPPORT A RAIN/SNOW MIX.
HAVE PUT IN A PERIOD OF MVFR CONDITIONS OVERNIGHT TO COVER THIS
POSSIBILITY. LOOKS LIKE ALL THE PRECIPITATION SHOULD END EARLY
SUNDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 259 PM CST SAT JAN 30 2016
A WEAK COLD FRONT IS EXPECTED TO MOVE ACROSS THE REGION LATER
TONIGHT INTO SUNDAY MORNING. A WAVE IS EXPECTED TO MOVE ALONG THE
FRONT LATE TONIGHT AND SUNDAY...BRINGING A SWATH OF PRECIPITATION
TO PORTIONS OF THE FORECAST AREA LATER THIS EVENING INTO SUNDAY
AFTERNOON.
MANY ISSUES TO CONTEND WITH TODAY WITH RESPECT TO PRECIPITATION
TYPES LATER TONIGHT. TEMPERATURES THIS AFTERNOON CLIMBED INTO
THE 40S AT MOST PLACES. THE LAST CHECK OF ROAD TEMPERATURES
WERE WELL INTO THE 40S TO AROUND 50. ALSO...THE OTHER MAJOR
PROBLEM WILL BE IF THERE WILL BE PRECIPITATION WILL IT WILL
GET COLD ENOUGH FOR MIXED PRECIPITATION.
MOST OF THE MODELS HAVE PRECIPITATION MOVING INTO PORTIONS OF
NORTH-CENTRAL AND FAR NORTHEAST WISCONSIN LATER TONIGHT.
HOWEVER...THE LATEST HRRRR AND RAP MODELS DO NOT PRODUCE
PRECIPITATION INTO THIS REGION WHERE IT WOULD GET COLD ENOUGH
FOR FREEZING RAIN...SLEET OR SNOW. CONTEMPLATED ISSUING A WINTER
WEATHER ADVISORY FOR MARATHON UP THROUGH NORTHERN MARINETTE
COUNTY...BUT THE FACT THE MESO MODELS DO NOT PRODUCE PRECIPITATION
MADE ME HOLD OFF ON ISSUING AN ADVISORY. IF THE GFS/ECMWF IS
CORRECT...THERE MAY BE A PERIOD LATE TONIGHT FOR SOME FREEZING
RAIN...SLEET OR SNOW THAT COULD MAKE ROADS SLICK.
THE WAVE IS EXPECTED TO MOVE EAST OF THE AREA ON SUNDAY. THE
PRECIPITATION SHOULD COME TO AN END SUNDAY AFTERNOON OR EVENING.
WENT WITH THE THREE HOURLY TEMPERATURES ON GUIDANCE FOR LOWS
AND CLOSER TO THE MAV GUIDANCE. HIGHS ON SUNDAY WILL BE IN THE
30S AGAIN.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 259 PM CST SAT JAN 30 2016
THE MID LEVEL TROUGH WILL CONTINUE TRACKING AWAY FROM WISCONSIN
SUNDAY NIGHT...ENDING PRECIPITATION FROM WEST TO EAST AS
PRECIPITATION CHANGES OVER TO ALL SNOW ACROSS THE EASTERN CWA BY
THE EVENING HOURS. NORTH NORTHWESTERLY WINDS ON THE BACKSIDE OF
THE LOW WILL BRING LAKE EFFECT SHOWERS TO THE LAKE SUPERIOR
SNOWBELT REGION ON MONDAY AND MONDAY NIGHT.
THE MAIN FOCUS IN THE LONG TERM CONTINUES TO BE THE LOW HEADING
FOR THE GREAT LAKES TUESDAY AND WEDNESDAY. DESPITE THE PRIOR 00Z
MODEL RUNS...THE 12Z SUITE OF RUNS HAS COME INTO BETTER AGREEMENT
REGARDING THE TIMING AND TRACK OF THE LOW. THE LONE EXCEPTION IS
THE VERY SLOW NAM WHICH HAS MOST OF THE CWA DRY THROUGH TUESDAY
AFTERNOON. GIVEN EVEN THE PREVIOUSLY SLOWER CANADIAN HAS LATCHED
ONTO THIS FASTER SOLUTION WHICH BRINGS THE HEAVY SNOW INTO THE
AREA BY TUESDAY AFTERNOON...WILL PUT SOME RESOLUTION INTO THE
TUESDAY POP GRID AND GO WITH LOWER POPS IN THE MORNING...AND RAMP
THEM UP IN THE AFTERNOON. IN ADDITION TO THE SNOW...THE VERY TIGHT
PRESSURE GRADIENT WILL CAUSE BLOWING AND DRIFTING OF SNOW ACROSS
THE FORECAST AREA AS MODERATE TO HEAVY SNOW GETS GOING ACROSS THE
REGION.
THE LONG RANGE MODELS TRACK THE LOW A BIT FURTHER WEST THAN
YESTERDAYS RUNS...TRACKING THE LOW OVER SOUTHERN TO CENTRAL LAKE
MICHIGAN TUESDAY NIGHT...THEN OVER LAKE HURON INTO CANADA ON
WEDNESDAY. THIS WESTWARD JOG MAKES SENSE AS THE NORTHERN STREAM
LOW OVER SOUTHERN CANADA IS CLOSE ENOUGH TO PULL THE SOUTHERN
STREAM LOW CLOSER WEST. THERE ARE STILL SOME DIFFERENCES REGARDING
THE EXACT TRACK AND TIMING...HOWEVER WITH A RELATIVELY DECENT
CONSENSUS TUESDAY NIGHT WILL RAISE POPS TO CATEGORICAL ACROSS THE
FORECAST AREA AS THE DRY SLOT LOOKS TO REMAIN JUST OFF TO THE EAST
ON TUESDAY NIGHT. THE TIGHT PRESSURE GRADIENT WILL REMAIN TUESDAY
NIGHT...WITH CONTINUED BLOWING AND DRIFTING SNOW.
THE LOW RAPIDLY TRACKS AWAY FROM THE AREA TOWARDS WESTERN QUEBEC
ON WEDNESDAY...WITH LINGERING SNOW SHOWERS AS WELL AS SIGNIFICANT
BLOWING AND DRIFTING SNOW WITH THE CONTINUED TIGHT PRESSURE
GRADIENT. THIS WILL LIKELY MAKE SNOW REMOVAL AND TRAVEL DIFFICULT
THROUGH MUCH OF WEDNESDAY. IN ADDITION A NORTH NORTHWESTERLY
COMPONENT WILL TURN ON THE LAKE SUPERIOR SNOW BELT
REGION...BOOSTING TOTALS ACROSS THAT AREA ON WEDNESDAY. OVERALL IT
LOOKS LIKE A GOOD BET FOR 6 OR MORE INCHES OF SNOW ACROSS
NORTHEAST WISCONSIN FROM TUESDAY THROUGH WEDNESDAY. THE DRY SLOT
COULD STILL PLAY A ROLE...ESPECIALLY IF THE SYSTEM TRACKS FURTHER
WEST...WHICH IS A POSSIBILITY GIVEN THE PROXIMITY TO THE NORTHERN
STREAM LOW. THE DRY SLOT WOULD TEND TO HOLD DOWN
TOTALS...THEREFORE THERE IS RECITANCE IN PUTTING MORE SOLID
SNOWFALL AMOUNTS DOWN AT THIS JUNCTURE.
BEHIND THE LOW A COLD ARCTIC AIRMASS WILL FILTER IN AS 850 MB
TEMPERATURES PLUNGE INTO THE MIDDLE TO UPPER TEENS BELOW ZERO FOR
THE LATE PART OF THE WEEK AND INTO THE EARLY PART OF NEXT
WEEKEND. SEVERAL WEAK LOW PRESSURE SYSTEMS AND LAKE EFFECT WILL
BRING SEVERAL OPPORTUNITIES FOR LIGHT SNOW AT TIMES TO THE REGION
FOR THE LATE PART OF THE WEEK AND INTO THE WEEKEND. HOWEVER THESE
SYSTEMS WILL HAVE MEAGER MOISTURE TO WORK WITH...SO SIGNIFICANT
SNOWFALL DURING THE LATE PART OF THE EXTENDED IS NOT ANTICIPATED.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1138 AM CST SAT JAN 30 2016
A WEAK COLD FRONT IS EXPECTED TO MOVE ACROSS THE REGION LATE
TONIGHT INTO SUNDAY MORNING. THIS FEATURE WILL BRING A CHANCE OF
RAIN...FREEZING RAIN...SLEET AND SNOW TO THE REGION LATE THIS
EVENING INTO SUNDAY MORNING. FOR THE FOX VALLEY AND LAKESHORE
REGION...THE PRECIPITATION SHOULD BE MAINLY RAIN. TO THE NORTH AND
WEST OF THE FOX VALLEY...A MIX OF RAIN...FREEZING RAIN...SLEET AND
SNOW IS EXPECTED DEPENDING ON BOUNDARY LAYER TEMPERATURES AND HOW
QUICK THESE BOUNDARY LAYER TEMPERATURES COOL OFF LATER TONIGHT.
WENT MORE FREEZING RAIN AND SNOW FOR THE 00Z TAFS AT
KAUW/KRHI/KCWA. THE PRECIPITATION COULD POSSIBLY STAY JUST SOUTH
OF KRHI IF SOME OF THE MODELS ARE CORRECT. ANY PRECIPITATION
SHOULD COME TO AN END BY MID AFTERNOON ON SUNDAY ACROSS NORTHEAST
WISCONSIN.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....ECKBERG
LONG TERM......KURIMSKI
AVIATION.......ECKBERG
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1116 AM CST SAT JAN 30 2016
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 220 AM CST SAT JAN 30 2016
A COUPLE PIECES OF UPPER LEVEL ENERGY GOING TO COME TOGETHER AND
PRODUCE SOME PRECIPITATION ACROSS THE REGION LATER TONIGHT INTO
SUNDAY. FIRST PIECE OF ENERGY WILL MOVE OUT OF THE SOUTHERN
ROCKIES...LIFTING NORTHEAST ACROSS IA TO SOUTHERN WI/NORTHERN IL.
THE OTHER PIECE OF ENERGY IS MORE ELONGATED/STRONGER IN NATURE AND
WILL MOVE OUT OF THE PAC NW TO THE UPPER MISSISSIPPI RIVER VALLEY
BETWEEN 12-18Z SUN. PRETTY GOOD FRONTOGENETIC RESPONSE BETWEEN
THESE TWO UPPER LEVEL FEATURES...EVIDENCED IN A NORTHWEST-
SOUTHEAST RUNNING X-SECTION. RIGHT ENTRANCE REGION OF A 100 KT
UPPER LEVEL JET STREAK WILL ENHANCE LIFT TONIGHT. SATURATION IS
MORE TOP DOWN...SO THERE SHOULD BE ICE IN THE CLOUD.
HOWEVER...THERE IS ALSO A STRONG PUSH OF LOW LEVEL/SFC WARMING.
HIGHS WILL NEAR 40 FOR SOME TODAY...AND LIKELY STAY ABOVE FREEZING
TONIGHT FOR THE SOUTHERLY 1/2 OF THE FORECAST AREA. A FEW DEGREE
REBOUND FROM MORNING LOWS IS EXPECTED ON SUNDAY. SO PRECIPITATION
TYPE QUESTION REST ON THE SFC TEMPS/DEPTH OF THE WARM LAYER. AS IT
SITS...RAIN LOOKS TO BE THE PREDOMINANT TYPE FOR THE SOUTHERN 1/2
OF THE FORECAST AREA. MORE SNOW-RAIN/SNOW TO THE NORTH. CAN/T RULE
OUT A SHORT PERIOD OF FREEZING RAIN THOUGH...WHERE IT COOLS ENOUGH
TO SUPPORT IT. WITH A SLIGHTLY WARMER ATMOSPHERE EXPECTED...SNOW
AMOUNTS LOOK A LOT LESS COMPARED TO YESTERDAY...MOSTLY 1/2 INCH OR
LESS. OBVIOUSLY IF ITS COLDER...AN INCH OR TWO WILL BE MORE
LIKELY.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 220 AM CST SAT JAN 30 2016
OKAY. THERE IS A STORM COMING. ITS GOING TO HAVE SIGNIFICANT IMPACTS
FOR MANY. SNOW IN EXCESS OF A FOOT. CONSIDERABLY BLOWING AND
DRIFTING. BLIZZARD/NEAR BLIZZARD CONDITIONS POSSIBLE. YOU WILL HEAR
A LOT ABOUT THE STORM FROM NOW UNTIL IT MOVES IN...AND RIGHTLY SO.
BUT THERE REMAINS A LOT OF UNCERTAINTY YET IN TRACK OF THE STORM
AND ITS OVERALL EVOLUTION. CONFIDENCE IS LOW IN THESE AREAS.
CONFIDENCE HIGHER IN ITS SNOW/WIND POTENTIAL. ANTICIPATE SOME
CHANGES TO THE FORECAST AS TUE APPROACHES AND TRENDS BECOME CLEARER.
PREPARE FOR THE WORST...BE THANKFUL IF THE TRACK SHIFTS. BUT DON/T
UNDER ESTIMATE WHAT THE STORM COULD DO.
UPPER LEVEL TROUGH STILL SLATED TO SWING OUT OF THE DESERT
SOUTHWEST...DRIVING ACROSS THE PLAINS TO ACROSS THE GREAT LAKES BY
06-12Z WED. THE SFC LOW LEADS THE UPPER LEVEL LOW A BIT...MOVING
ROUGHLY OVER NORTHERN ILL BY 00Z WED. MODELS DIFFER IN
PLACEMENT...BUT AGREE WITH GENERAL AREA. ALL HAVE STRONG LOW LEVEL
THERMODYNAMICS RUNNING AHEAD OF THE STACKED LOW...WITH A VERY STRONG
RESPONSE THROUGH THE LEVELS IN QG CONVERGENCE. SUMMERY FETCH OF 850
MB MOISTURE TRANSPORT RUNNING NORTHWARD ALONG THE SYSTEM/S COLD
FRONT. MUCH OF THAT WILL BE USED FOR CONVECTIVE LINE ASSOCIATED WITH
THE FRONT...BUT AMPLE/DEEP SATURATION MOVES NORTH-WEST INTO THE
STORM/S DEFORMATION REGION. 150+ KT 300 MB JET GOING TO ENHANCE THE
ALREADY STRONG LIFT TUE PER ITS LEFT EXIT REGION...WHICH IS
CURRENTLY PROGGED TO MOVE RIGHT ACROSS THE LOCAL FORECAST AREA. ITS
PACKING A PUNCH...NO DOUBT.
GFS COBB OUTPUT HAS LAID OUT AROUND A FOOT OR GREATER FOR LA CROSSE
OVER ITS LAST 4 RUNS. CERTAINLY DOABLE WITH THAT FORCING...AND...AND
IF THE TRACK SLIDES THE DEFORMATION AXIS ACROSS THE REGION...WHICH
IT HAS BEEN DOING. IT LOOKS TO BE ALL OR NEARLY ALL SNOW FOR
PRECIPITATION TYPE. DEPENDING ON WHERE THE LOW ENDS UP...SOME
RAIN COULD MIX IN FOR THE SOUTHEAST/EAST PORTIONS OF THE FORECAST
AREA. FOR WIND...SFC GRADIENT TIGHTENING UP AS THE LOW
STRENGTHENS/MOVES IN. SUSTAINED 20 KTS WITH GUSTS IN THE MID 30S
REASONABLE IN THE OPEN/UNSHELTERED AREAS. A LOT OF
BLOWING/DRIFTING WOULD RESULT...WITH THE POTENTIAL FOR WHITE-OUT
CONDITIONS. TRAVEL COULD/WOULD BECOME IMPOSSIBLE/DANGEROUS IN THIS
SCENARIO. THERE WOULD BE ROAD CLOSURES.
WINTER STORM WATCHES AND/OR BLIZZARD WATCHES ARE STILL LIKELY FOR
TUE/TUE NIGHT...UNLESS THERE ARE CONSIDERABLE CHANGES IN THE
TRACK/STRENGTH OF THIS WINTER STORM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1116 AM CST SAT JAN 30 2016
WATCHING A SHORT WAVE TROUGH MOVING INTO THE WESTERN DAKOTAS LATE
THIS MORNING. WARM AIR ADVECTION ZONE AHEAD OF THIS WAVE IS
CAUSING SOME RADAR RETURNS OVER SOUTHWEST MINNESOTA...BUT SO
FAR...ONLY MID LEVEL CLOUDS ARE BEING REPORTED FROM THIS AREA. THE
30.16Z HRRR SUGGESTS THIS AREA OF RETURNS WILL CONTINUE TO
STRENGTHEN THROUGH THE AFTERNOON WITH SOME LIGHT RAIN OR SPRINKLES
POSSIBLE AT KRST BEFORE 00Z. LOOKING AT THE RAP BUFKIT SOUNDINGS
FOR THIS TIME FRAME...THERE IS STILL A LOT OF LOW LEVEL DRY AIR IN
PLACE AND WOULD NOT EXPECT MUCH MORE THAN SPRINKLES IF IT DOES
MOVE IN THIS AFTERNOON. OTHERWISE...THE TIMING FOR THE LIGHT RAIN
TO MOVE IN FROM OTHER 30.12Z MODELS IS EARLY THIS EVENING. THE
FORCING FROM THIS WAVE DOES NOT LOOK TO BE VERY STRONG SO
EXPECTING LITTLE OR NO VISIBILITY RESTRICTIONS TO OCCUR WITH
MAINLY VFR CEILINGS. THE EXCEPTION TO THAT MAY BE LATE TONIGHT AT
KLSE IF THE COLUMN CAN COOL ENOUGH TO SUPPORT A RAIN/SNOW MIX.
HAVE PUT IN A PERIOD OF MVFR CONDITIONS OVERNIGHT TO COVER THIS
POSSIBILITY. LOOKS LIKE ALL THE PRECIPITATION SHOULD END EARLY
SUNDAY MORNING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...04
AREA FORECAST DISCUSSION
NWS TUCSON AZ
925 PM MST SUN JAN 31 2016
.SYNOPSIS...EXPECT WIDESPREAD VALLEY RAIN...MOUNTAIN SNOW AND VERY
STRONG GUSTY WINDS TONIGHT INTO MONDAY AS A FAST MOVING STORM SYSTEM
MOVES EASTWARD ACROSS THE AREA. A CHANCE OF SNOW SHOWERS CONTINUES
MAINLY ACROSS THE WHITE MOUNTAINS MONDAY NIGHT INTO TUESDAY. MUCH
COLDER TEMPERATURES WILL ALSO OCCUR MONDAY INTO TUESDAY...AND A HARD
FREEZE APPEARS LIKELY FOR MUCH OF THE AREA TUESDAY NIGHT. DRY
CONDITIONS WITH A PRONOUNCED WARMING TREND WILL THEN PREVAIL LATER
THIS WEEK AND INTO NEXT WEEKEND.
&&
.DISCUSSION...8 PM SURFACE ANALYSIS SHOWED THAT THE APPROACHING COLD
FRONT EXTENDED FROM EASTERN CLARK COUNTY IN NEVADA SOUTH ACROSS
MOHAVE...LAPAZ AND YUMA COUNTIES IN ARIZONA. THE 9 PM REGIONAL
RADARS SHOWED THAT SHOWERS HAVE PUSHED INTO MARICOPA AND WRN PIMA
COUNTIES AS OF 9 PM REGIONAL. LATEST HRRR RUNS DEVELOP SHOWERS
ACROSS WESTERN/CENTRAL PIMA COUNTY THRU 10 PM THEN EXPAND IN AREAL
COVERAGE OF SHOWERS ACROSS THE AREA BETWEEN 11 PM AND 1 AM. LOW LEVEL
WIND SPEEDS OUT AHEAD OF THE FRONT...PER YUMA VAD WIND PROFILE...WERE
AS HIGH AS 45 KNOTS EARLIER THIS EVENING. EXPECT THESE WINDS TO
OVERSPREAD THE AREA WITH THEM MIXING DOWN TO THE SURFACE WITH THE
SHOWERS. MOUNTAIN SITES AND WIND PRONE AREAS NEAR MOUNTAIN GAPS WILL
SEE HIGH WIND WARNING TYPE WIND GUSTS WHILE THE REST OF THE EASTERN
TWO THIRDS OF THE AREA WILL HAVE WIND ADVISORY CRITERIA WIND GUSTS.
SNOW LEVELS...PER MOUNTAIN RAWS PLATFORMS...WERE IN THE 8000-9000
FOOT RANGE AS OF 8 PM AND EXPECT THEM TO CRASH DOWN IN THE 3000-4000
RANGE BY MONDAY MORNING. THE STRONG WINDS IN THE MOUNTAINS COMBINED
WITH THE FALLING SNOW WILL CAUSE BRIEF PERIODS OF BLIZZARD LIKE
CONDITIONS. CURRENT WIND AND WINTER TYPE WARNINGS AND ADVISORIES
STILL ON TRACK. BLOWING DUST HAS BEEN A CONCERN THIS EVENING WEST OF
TUCSON WHERE WE CURRENTLY HAVE A BLOWING DUST ADVISORY OUT UNTIL 10
PM. AS WINDS PICK UP ACROSS COCHISE COUNTY...WILL HAVE TO BE
CONCERNED WITH DUST COMING OFF THE WILLCOX PLAYA BEFORE THE RAIN
MOVES IN.
AFTER A BEAUTIFUL WARM WEEKEND...TEMPERATURE SHOCK WILL SETTLE IN ON
MONDAY WITH HIGHS 15-25 COOLER THAN SUNDAY.
&&
.AVIATION...VALID THRU 02/00Z.
SCATTERED -SHRA WILL DEVELOP WEST-TO-NORTH OF KTUS THIS EVENING
FOLLOWED NUMEROUS VALLEY -SHRA AND MOUNTAIN SHSN LATE TONIGHT INTO
MONDAY MORNING. SCATTERED VALLEY -SHRA AND MOUNTAIN -SHSN WILL THEN
OCCUR MAINLY EAST OF KTUS MONDAY AFTERNOON. EXPECT MVFR CONDITIONS
AND OCCASIONAL IFR CONDITIONS ASSOCIATED WITH THIS PRECIPITATION.
OTHERWISE...CLOUD DECKS ABOVE 20K FT MSL THIS EVENING WILL LOWER TO
AROUND 5-9K FT MSL LATE TONIGHT AND CONTINUE INTO MONDAY AFTERNOON.
SURFACE WIND WILL GENERALLY BE SWLY/WLY AT 15-30 KTS WITH GUSTS OF
30-45 KTS INTO EARLY MONDAY AFTERNOON...THEN WIND SPEEDS WILL
DECREASE TO 10-20 KTS WITH GUSTS OF 20-30 KTS MONDAY AFTERNOON.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...WIDESPREAD VALLEY RAIN AND MOUNTAIN SNOW WILL OCCUR
INTO MONDAY MORNING...THEN PRECIPITATION WILL DECREASE FROM WEST-TO-
EAST MONDAY AFTERNOON. EXPECT STRONG AND GUSTY SOUTHWEST TO
NORTHWEST WINDS THROUGH MONDAY AFTERNOON. ISOLATED TO SCATTERED SNOW
SHOWERS WILL CONTINUE MAINLY ACROSS THE WHITE MOUNTAINS MONDAY NIGHT
INTO TUESDAY. DRY CONDITIONS WILL THEN PREVAIL AREA-WIDE TUESDAY
NIGHT INTO NEXT WEEKEND. MUCH COLDER TEMPERATURES WILL OCCUR MONDAY
INTO WEDNESDAY FOLLOWED BY A PRONOUNCED WARMING TREND THURSDAY INTO
NEXT WEEKEND.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 2 PM MST
MONDAY FOR AZZ510 ABOVE 5000 FEET.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 2 PM MST
MONDAY FOR AZZ507>509-511>514 ABOVE 4500 FEET.
HIGH WIND WARNING FROM 10 PM THIS EVENING TO 2 PM MST MONDAY FOR
AZZ507-511>514.
WIND ADVISORY FROM 10 PM THIS EVENING TO 2 PM MST MONDAY FOR
AZZ503-504-506>510-515.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS TAUNTON MA
322 AM EST MON FEB 1 2016
.SYNOPSIS...
UNSEASONABLY MILD WEATHER CONTINUES TODAY WITH JUST A SPOT SHOWER
ALONG AND AHEAD OF AN APPROACHING COLD FRONT. WEAK HIGH PRESSURE
ARRIVES TUESDAY WITH DRY AND SOMEWHAT COOLER CONDITIONS. WIDESPREAD
RAIN WITH EMBEDDED HEAVIER SHOWERS...POSSIBLY A RUMBLE OF THUNDER...
FOR WEDNESDAY. ACCOMPANYING THREATS OF PATCHY LIGHT FREEZING RAIN
OVER N/W MASS AND GUSTY SW WINDS ELSEWHERE. SEASONABLE TEMPERATURES
RETURN BY THURSDAY AHEAD OF A STORM REMAINING WELL OFFSHORE ON FRIDAY.
A LOW CONFIDENCE FORECAST FOR THE WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST RUNS OF THE HRRR AND RAP CONTINUE TO INDICATE DEVELOP OF
LOW CLOUDS ACROSS PORTIONS OF SOUTHEAST MA THIS MORNING. THERE
HAVE BEEN HINTS IN THE SURFACE OBSERVATIONS...WITH SOME SITES
BRIEFLY SHOWING EITHER PATCHY FOG OR LOWER CLOUD BASES. AT THIS
TIME THOUGH...THERE HAS BEEN NOTHING TO SUGGEST THESE CONDITIONS
WILL PERSIST FOR AN EXTENDED PERIOD OF TIME. SHOULD THESE CLOUDS
DO DEVELOP AND PERSIST...THERE WOULD BE MAJOR IMPLICATIONS FOR THE
FORECAST TODAY ACROSS SOUTHEAST MA. WILL CONTINUE TO MONITOR.
A COLD FRONT WILL CROSS SOUTHERN NEW ENGLAND TODAY. BEFORE IT
COMPLETES ITS JOURNEY THOUGH...EXPECTING ANOTHER VERY MILD DAY.
SOUTHWEST WINDS CONTINUE THIS MORNING...THEN BECOME WEST BEHIND
THIS FRONT. EXPECTING TEMPERATURES IN THE 50S...WITH A FEW
LOCATIONS APPROACHING 60 DEGREES. THESE TEMPERATURES ARE 20-25
DEGREES ABOVE NORMAL.
MOISTURE WILL AGAIN BE A LIMITING FACTOR FOR SHOWERS LATER TODAY.
THINKING THE GREATEST RISK FOR SHOWERS WILL BE ALONG THE SOUTH
COAST WHERE FLOW OFF THE OCEAN WILL PROVIDE THE GREATEST AMOUNT.
STILL...ONLY THINKING A CHANCE FOR SHOWERS AT MOST THERE. EVEN
LESS OF A RISK FARTHER INLAND.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
FRONT AND ASSOCIATED MOISTURE/CLOUDS/SPOT SHOWERS WILL BE ALONG
THE SOUTH COAST AT 00Z AND CONTINUING TO MOVE OFFSHORE WITH A DRIER
POST-FRONTAL AIRMASS OVERSPREADING THE REGION. MINIMUM
TEMPERATURES STILL ABOVE NORMAL...AND CLOSE TO NORMAL HIGH
TEMPERATURES FOR THIS TIME OF YEAR.
TUESDAY...
WEAK HIGH PRESSURE BUILDS ACROSS NEW ENGLAND. THE MAJOR AXIS OF
COLD AIR ADVECTION REMAINS TO OUR NORTH. WHILE MAX TEMPERATURES
WILL BE 10-15 DEGREES LOWER THAN MONDAY...THEY WILL ALSO STILL BE
ABOVE NORMAL. LIGHT NORTHWEST WINDS TO START WILL BECOME LIGHT AND
VARIABLE MIDDAY. THIS COULD LEAD TO LOCAL SEABREEZES ALONG THE
COASTS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
*/ HIGHLIGHTS...
- RAIN WITH EMBEDDED HEAVIER SHOWERS WEDNESDAY...GUSTY SW WINDS
- INITIAL THREAT OF PATCHY LIGHT FREEZING RAIN OVER N/W MASS
- RETURN TO MORE SEASONABLE TEMPERATURES BEGINNING THURSDAY
- KEEPING THE OFFSHORE STORM AT BAY FOR FRIDAY
- LOW CONFIDENCE FORECAST FOR THE WEEKEND INTO EARLY NEXT WEEK
*/ OVERVIEW...
AMPLIFIED WEATHER PATTERN OVER N AMERICA IS PERHAPS ON THE HORIZON
INTO MID-FEBRUARY. EVALUATING STRATOSPHERIC TEMPERATURES AT 10 MB...
IMPRESSIVE WARMTH OVER ASIA PIVOTING THE STRATOSPHERIC POLAR VORTEX
INTO THE N-ATLANTIC IF YOU ACCEPT THE FORECAST FOR WHAT IT IS WORTH.
THE POLAR JET ALTERS N-S STRAIGHT INTO THE C-CONUS DOWN INTO THE N
GULF. BOTH CLIMATE FORECAST SYSTEM /CFS/ AND EC ENSEMBLE PREDICTION
SYSTEM /EPS/ HIGHLIGHT A NOTEWORTHY NEGATIVE 2M TEMPERATURE ANOMALY
ACROSS THE C-CONUS ACCORDINGLY BY MID-FEBRUARY. THE ARCTIC AS WELL
AS THE E-PACIFIC OSCILLATION TRANSITION NEGATIVE WITH TIME.
BUT THAT IS ONLY ONE PIECE OF THE PUZZLE...THE OTHER BEING EL NINO
SOUTHERN OSCILLATION WITH POSSIBLE PHASE 3 THROUGH 5 MADDEN-JULIAN
CONTRIBUTIONS...KEEPING THE PACIFIC N-AMERICA PATTERN POSITIVE WITH
RIDGING OVER THE NE-PACIFIC AND A PROGRESSIVE FLOW REGIME DOWNSTREAM
WITH NO INDICATIONS OF BLOCKING ACROSS THE N-ATLANTIC. A COMBINATION
IN ALL WHICH WARRANTS WARM CONDITIONS OVER THE E-CONUS AS WE SAW
DURING NOVEMBER AND DECEMBER WHEN THE MADDEN-JULIAN OSCILLATION WAS
GREATLY CONTRIBUTING IN ADDITION TO THE EL NINO SIGNAL.
A CHALLENGING LONG-TERM FORECAST AS BOTH STORM TRACK AND BAROCLINIC
ZONE ALONG WITH THE ACCOMPANYING SW-NE BELT OF WESTERLIES STRETCHED
ACROSS THE E-CONUS ARE LIKELY TO WOBBLE GRADUALLY E WITH TIME. SO TO
BEGIN FEBRUARY WE ARE EXPECTED TO STAY ON THE INSIDE OF THE STORM
TRACK WITHIN THE WARM SECTOR...A WARM-WET PATTERN ANTICIPATED. BUT
BY MID-FEBRUARY WE MAY FIND OURSELVES ON THE FENCE RAIL BETWEEN THE
AIRMASSES WHEN EVALUATING H85 TEMPERATURES WITH THE EXPECTATION OF
COASTAL-OFFSHORE STORM DEVELOPMENT.
LOTS OF INTANGIBLES WITH LESSER CONFIDENCE FURTHER OUT IN TIME WITH
THE FORECAST. BUT OVERALL THE DISCUSSION ABOVE IS IN STEP WITH THE
CFS AND EPS WITH THE NE CONUS NAMELY S NEW ENGLAND WOBBLING WITHIN
THE TRANSITION ZONE OF BELOW- AND ABOVE-AVERAGE TEMPERATURES W TO E.
CONTINUED CHALLENGES WITH THE JUXTAPOSITIONING OF EL NINO AND ARCTIC
OSCILLATION.
WILL HIGHLIGHT SIGNIFICANT OUTCOMES AND POTENTIAL IMPACTS BELOW.
*/ DISCUSSION...
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...
RAIN WITH EMBEDDED HEAVIER SHOWERS THE HEIGHT OF WHICH CONTINUES TO
BE AROUND MIDDAY / EARLY AFTERNOON WEDNESDAY. HIGHLY ANOMALOUS DEEP
LAYER MOISTURE CONVERGING AND UNDERGOING ASCENT AHEAD OF A SWEEPING
COLD FRONT AND BENEATH DIFFLUENCE ALOFT. BUT THE FRONT QUICK-MOVING
WITH THE SNOWPACK MELTED IN THE DAYS PRIOR...NOT EXPECTING MUCH IN
THE WAY OF URBAN / POOR-DRAINAGE FLOODING ISSUES. RAIN EXPECTED TO
BE MOVING OUT BY EVENING.
COULD SEE A RUMBLE OF THUNDER. HIGH-RES GUIDANCE NOW AVAILABLE HAS
COMBINATION OF NEGATIVE SHOWALTERS / WEAK INSTABILITY / K-INDICES
GREATER THAN 30. A CONDITIONALLY UNSTABLE PROFILE ALOFT OF SUB-
TROPICAL PROPERTIES WITH PRECIPITABLE WATERS NEARLY 1.5-INCHES ABOVE
THE INVERSION NOTED BELOW. WILL INTRODUCE ISOLATED THUNDER IN THE
FORECAST.
WINDS CONTINUE TO BE A CONCERN. SW WIND CONSENSUS AT 2 KFT AGL AHEAD
OF THE COLD FRONT AT 50 TO 60 MPH. FORECAST SOUNDINGS INDICATING A
DEEP INVERSION ENOUGH SO THAT FORECAST WARMER 2M TEMPERATURES MAY
NOT OVERCOME WHICH LIMITS MIX-DOWN OF MOMENTUM TO THE SURFACE. BUT
CONSIDERING THE GRADIENT-ISALLOBARIC WIND RESPONSE WITH POTENTIAL
MECHANICAL MIXING PER POSSIBLE HEAVY RAINFALL...30 TO 40 MPH GUSTS
WILL BE POSSIBLE...AS INDICATED BY CIPS ANALOGS OVER SE NEW ENGLAND.
MAY NEED WIND ADVISORY HEADLINES FOR THE SUSTAINED WINDS ALONE. FOR
NOW WILL CONTINUE MENTIONING OF POTENTIAL HAZARDS IN THE HAZARDOUS
WEATHER OUTLOOK. FOCUS ON THE MIDDAY / AFTERNOON HOURS DURING HEIGHT
OF WET WEATHER.
LIGHT FREEZING RAIN WITH ONSET WEDNESDAY MORNING CONTINUES TO BE
POSSIBLE OVER N/W MASS AS FORECAST MODEL CONSENSUS AND CIPS ANALOGS
INDICATE. DESPITE THE MORNING EROSION OF SUB-FREEZING AIR...SOME OF
IT MAY REMAINED TRAPPED WITHIN THE VALLEYS. THINK ISOLATED POCKETS
WITH A SHORT-WINDOW OF IMPACTS INTO MID-MORNING. TEMPERATURES RIGHT
AROUND FREEZING...LOW CONFIDENCE ON ACCUMULATION. FOCUS ESPECIALLY
ON N/W FRANKLIN COUNTY MASS. MAY HAVE TO ISSUE ADVISORY HEADLINES
WITH LIGHT RAIN MOVING IN AFTER MIDNIGHT. AGAIN A SHORT WINDOW.
HIGHS POTENTIALLY REACHING THE 60 DEGREE MARK. WILL SEE RAIN / LOW
CLOUDS / FOG ESPECIALLY WITH HIGHER DEWPOINT AIR OVERRUNNING THE
COLDER OCEAN WATERS QUICKLY CLEAR OUT THROUGH EVENING AS WINDS BACK
NW. HIGH PRESSURE FOLLOWS THAT USHERS COOLER AIR S RESULTING IN MORE
SEASONABLE TEMPERATURES.
THURSDAY THROUGH FRIDAY...
FORECAST SOLUTIONS CONTINUE TO POORLY HANDLE MID-LEVEL ENERGY THRU
AN OVERALL OPEN WAVE TROUGH. NOTING THE ABSENCE OF A DEEPER TROUGH
ESPECIALLY NEITHER CLOSED NOR NEGATIVELY TILTED...CAN NOT SEE THE
INFLECTION POINT LOW TO THE OFFSHORE COLD FRONT / BAROCLINIC ZONE
BECOMING EXCEPTIONALLY STRONG. ENSEMBLE MEANS AGREE UP ON A 1000 MB
LOW. SUBSEQUENTLY DO NOT EXPECT A RATHER ROBUST DEFORMATION ZONE
N/NW OF THE LOW...THUS IMPACTS REMAIN MAINLY S/E OF THE COASTLINE
WITH MOST OF THE FORCING AND MOISTURE KEPT OUT TO SEA. THEN AGAIN
SOME CONCERN AS TO HOW FAR THE COLD FRONT PUSHES OFFSHORE WEDNESDAY
NIGHT. HIGH PRESSURE IS RIDGING OUT OF THE S RATHER THAN THE N.
WHILE IT IS POSSIBLE SOMETHING MAY SKIRT BY...AM MORE CONCERNED AS
TO POTENTIAL OCEAN-EFFECT DEVELOPMENT WITH A COLDER AIRMASS SINKING
S WITH DECENT N-FLOW BENEATH MID-LEVEL FORCING. MAY HAVE TO WATCH
FOR IMPACTS OVER THE CAPE AND ISLANDS AS A RESULT.
OTHERWISE HIGH PRESSURE AND DRY WEATHER. COLDER AIRMASS BUILT S WITH
SOME ARCTIC ATTRIBUTES. INITIALLY MILD ON THURSDAY WITH SUNSHINE
EXPECTED...TEMPERATURES BECOME MORE SEASONABLE FOR THIS TIME OF YEAR
ON FRIDAY.
NEXT WEEKEND INTO EARLY NEXT WEEK...
KEEPING WITH ENSEMBLE MEANS. N AND S STREAM ENERGY BIFURCATING THE
REGION THE FIRST OF WHICH LOOKS TO REINFORCE ARCTIC AIR S ALONG WITH
SOME SPOTTY SNOW SHOWERY WEATHER TO THE N/W. THE SECOND POTENTIALLY
EVOLVES INTO SOMETHING BIGGER OFFSHORE. THE TWO APPEAR SEPARATE WITH
PASSAGE...PHASING FURTHER DOWNSTREAM WITHING THE PROGRESSIVE FLOW
PATTERN. A LOT OF SPREAD BETWEEN ENSEMBLE AND OPERATIONAL FORECAST
GUIDANCE ALIKE. A LOW CONFIDENCE FORECAST.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
TODAY...STILL WATCHING THE POTENTIAL FOR IFR CIGS ACROSS SOUTHEAST
MA. GUIDANCE CONTINUES TO SUGGEST IT...WITH SOME BRIEF SUPPORT
FROM SURFACE OBSERVATIONS AT TIMES. AS OF YET NOT EVEN CLOSE TO
BEING AS PREVALENT AS SOME MODELS WOULD SUGGEST. WILL CONTINUE TO
MONITOR. LOW CONFIDENCE THIS IFR DECK COULD DEVELOP RAPIDLY LATE
TONIGHT.
WITH A COLD FRONT QUICKLY CROSSING THE REGION...EXPECTING MAINLY
VFR CONDITIONS. PATCHY MVFR IN ISOLATED SHOWERS. SOUTHWEST WINDS
CONTINUE. MUCH STRONGER SOUTHWEST WINDS AT 2 KFT LEADING TO A
RISK FOR LLWS THIS MORNING. THIS RISK WILL DIMINISH AS THE CORE OF
THIS LOW LEVEL JET MOVES OFFSHORE BY THIS AFTERNOON. WEST TO
NORTHWEST GUSTS UP TO 25 KT AS THIS COLD FRONT PASSES BY.
TONIGHT...HIGH CONFIDENCE VFR WITH DRY WEATHER. NORTHWEST WINDS
BECOMING LIGHT NORTH.
TUESDAY...HIGH CONFIDENCE VFR. LIGHT NORTH WINDS VEER TO N-NE
DURING THE DAY. WILL SEE INCREASING MID-HIGH CLOUDS LATE
KBOS TERMINAL...ONLY TIMEFRAME OF LOW FORECAST CONFIDENCE IN TAF
IS FROM 12Z-17Z WHEN IFR CIGS MAY BRIEFLY IMPACT LOGAN/S
AIRSPACE. TYPICALLY SW WINDS ENOUGH OF LAND TRAJECTORY TO PRECLUDE
IFR CONDITIONS. KEPT THESE LOWER CLOUDS FEW-SCT AT THIS TIME. MAIN
CORE OF THESE LOWER CLOUDS SHOULD BE SOUTH OF THE TERMINAL.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK /TUESDAY NIGHT - FRIDAY NIGHT/...MODERATE CONFIDENCE.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...
CIGS LOWERING MVFR-IFR W TO E WITH WIDESPREAD RAIN WITH EMBEDDED
+SHRA BEGINNING WEDNESDAY MORNING. POSSIBLE TSRA ESPECIALLY S/SE
TERMINALS. POTENTIAL -FZRA OVER N/W INTERIOR VALLEYS MAINLY AROUND
WEDNESDAY MORNING. S/SW-WINDS WITH POTENTIAL 30 TO 40 KT GUSTS
AROUND MIDDAY INTO AFTERNOON... ESPECIALLY WITH +SHRA. LLWS IMPACTS
AS WELL 2 KFT AGL WITH 50-60 KT SW WINDS. IMPROVING WEDNESDAY
NIGHT TO VFR AS WINDS BACK W/NW.
THURSDAY INTO FRIDAY NIGHT...
WILL KEEP IT VFR WITH N-WINDS. CONCERNS OVER SE TERMINALS ESPECIALLY
CAPE AND ISLANDS WITH POTENTIAL MVFR / IFR AND -RA / -SN.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE.
A COLD FRONT WILL CROSS THE WATERS THIS AFTERNOON AND EVENING.
SOUTHWEST WINDS WILL VEER WEST-NORTHWEST AS THIS FRONT PASSES BY.
GUSTS UP TO 25 KT POSSIBLE UNTIL THIS FRONT PASSES BY. THE OTHER
STORY WILL BE ROUGH SEAS...FIRST ACROSS THE SOUTHERN COASTAL
WATERS...THEN EXPANDING TO THE EASTERN OUTER COASTAL WATERS BY
THIS AFTERNOON. GOOD VISIBILITY...WITH THE RISK OF A SPOT SHOWER
THIS AFTERNOON AND EVENING.
WINDS AND SEAS DIMINISH TONIGHT INTO TUESDAY...WITH SEAS TAKING
LONGER. SMALL CRAFT ADVISORIES WILL CONTINUE TODAY...THEN
GRADUALLY BE DROPPED TONIGHT INTO TUESDAY.
OUTLOOK /TUESDAY NIGHT - FRIDAY NIGHT/...MODERATE CONFIDENCE.
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...
WIDESPREAD RAIN WITH EMBEDDED HEAVIER SHOWERS BEGINNING WEDNESDAY
MORNING. ISOLATED THUNDERSTORMS POSSIBLE. S/SW-WINDS WITH POTENTIAL
30 TO 40 KT GUSTS WITH HEAVY RAIN SHOWERS ESPECIALLY ACROSS THE S/SE
WATERS. GALES LIKELY. SOME VISIBILITY ISSUES. WAVES BUILDING 8-10
FEET. IMPROVING WEDNESDAY NIGHT AS WINDS BACK NW AND BECOME LIGHT
ALLOWING WAVES TO DIMINISH.
THURSDAY INTO FRIDAY NIGHT...
PERSISTENT N/NW WINDS WITH THE PRESENCE OF AN OFFSHORE STORM AROUND
THURSDAY NIGHT INTO FRIDAY. RAIN/SNOW MIX MAY SKIRT SE NEW ENGLAND
IF NOT OCEAN-EFFECT ACTIVITY. WAVES SLOW TO DIMINISH. REMAINING
ABOVE 5-FEET ON THE OUTER WATERS.
&&
.CLIMATE...
RECORD HIGHS FOR FEB 1ST - 2ND - 3RD - 4TH...
BOS...66/1989 - 55/2014 - 59/1991 - 64/1991
BDL...67/1989 - 54/1981 - 61/1991 - 64/1991
PVD...64/1989 - 57/1973 - 60/1991 - 66/1991
ORH...61/1989 - 62/1991 - 57/1909 - 53/1946
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ237.
SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR ANZ235.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ250.
SMALL CRAFT ADVISORY UNTIL 10 AM EST TUESDAY FOR ANZ254-255.
SMALL CRAFT ADVISORY UNTIL 8 AM EST TUESDAY FOR ANZ256.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...SIPPRELL
AVIATION...BELK/SIPPRELL
MARINE...BELK/SIPPRELL
CLIMATE...WFO BOX STAFF
AREA FORECAST DISCUSSION
NWS TAUNTON MA
212 AM EST MON FEB 1 2016
.SYNOPSIS...
UNSEASONABLY MILD WEATHER CONTINUES TODAY WITH JUST A SPOT SHOWER
ALONG AND AHEAD OF AN APPROACHING COLD FRONT. WEAK HIGH PRESSURE
ARRIVES TUESDAY WITH DRY AND SOMEWHAT COOLER CONDITIONS.
WIDESPREAD RAIN MOVES IN LATE TUESDAY NIGHT THROUGH WEDNESDAY...
ALONG WITH SOME EMBEDDED HEAVIER SHOWERS. DRY AND MILD CONDITIONS
RETURN ON THURSDAY. WEAK LOW PRESSURE WAVES MAY PASS CLOSE ENOUGH
TO BRING SOME PATCHY RAIN AND/OR SNOW BACK TOWARD THE COASTAL
PLAIN LATE THIS WEEK INTO THIS WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
LATEST RUNS OF THE HRRR AND RAP CONTINUE TO INDICATE DEVELOP OF
LOW CLOUDS ACROSS PORTIONS OF SOUTHEAST MA THIS MORNING. THERE
HAVE BEEN HINTS IN THE SURFACE OBSERVATIONS...WITH SOME SITES
BRIEFLY SHOWING EITHER PATCHY FOG OR LOWER CLOUD BASES. AT THIS
TIME THOUGH...THERE HAS BEEN NOTHING TO SUGGEST THESE CONDITIONS
WILL PERSIST FOR AN EXTENDED PERIOD OF TIME. SHOULD THESE CLOUDS
DO DEVELOP AND PERSIST...THERE WOULD BE MAJOR IMPLICATIONS FOR THE
FORECAST TODAY ACROSS SOUTHEAST MA. WILL CONTINUE TO MONITOR.
A COLD FRONT WILL CROSS SOUTHERN NEW ENGLAND TODAY. BEFORE IT
COMPLETES ITS JOURNEY THOUGH...EXPECTING ANOTHER VERY MILD DAY.
SOUTHWEST WINDS CONTINUE THIS MORNING...THEN BECOME WEST BEHIND
THIS FRONT. EXPECTING TEMPERATURES IN THE 50S...WITH A FEW
LOCATIONS APPROACHING 60 DEGREES. THESE TEMPERATURES ARE 20-25
DEGREES ABOVE NORMAL.
MOISTURE WILL AGAIN BE A LIMITING FACTOR FOR SHOWERS LATER TODAY.
THINKING THE GREATEST RISK FOR SHOWERS WILL BE ALONG THE SOUTH
COAST WHERE FLOW OFF THE OCEAN WILL PROVIDE THE GREATEST AMOUNT.
STILL...ONLY THINKING A CHANCE FOR SHOWERS AT MOST THERE. EVEN
LESS OF A RISK FARTHER INLAND.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...
TONIGHT...
FRONT AND ASSOCIATED MOISTURE/CLOUDS/SPOT SHOWERS WILL BE ALONG
THE SOUTH COAST AT 00Z AND CONTINUING TO MOVE OFFSHORE WITH A DRIER
POST-FRONTAL AIRMASS OVERSPREADING THE REGION. MINIMUM
TEMPERATURES STILL ABOVE NORMAL...AND CLOSE TO NORMAL HIGH
TEMPERATURES FOR THIS TIME OF YEAR.
TUESDAY...
WEAK HIGH PRESSURE BUILDS ACROSS NEW ENGLAND. THE MAJOR AXIS OF
COLD AIR ADVECTION REMAINS TO OUR NORTH. WHILE MAX TEMPERATURES
WILL BE 10-15 DEGREES LOWER THAN MONDAY...THEY WILL ALSO STILL BE
ABOVE NORMAL. LIGHT NORTHWEST WINDS TO START WILL BECOME LIGHT AND
VARIABLE MIDDAY. THIS COULD LEAD TO LOCAL SEABREEZES ALONG THE
COASTS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* RAIN WITH EMBEDDED HEAVIER SHOWERS WEDNESDAY
* ANOTHER DRY AND MILD DAY ON THURSDAY...THEN COOLER TEMPERATURES
MOVE IN BY NEXT WEEKEND
* WEAK LOW PRESSURE WAVES PASSING S OF NEW ENGLAND MAY BRING PATCHY
LIGHT PRECIP TO THE COASTAL PLAIN LATE FRI INTO NEXT WEEKEND
OVERVIEW...
FAST MOVING MID AND UPPER LEVEL STEERING CURRENTS CONTINUE ACROSS
THE LOWER 48 EARLY IN THE LONG TERM PERIOD. CUTOFF LOW PRES MOVES
OUT OF THE SOUTHERN PLAINS STATES WITH DEEPENING SURFACE LOW
AROUND THE MID MISSISSIPPI VALLEY BY MID WEEK. AS THIS LOW DEEPENS
FURTHER WHILE MOVING ACROSS THE GREAT LAKES INTO CENTRAL CANADA...
ITS COLD FRONT SWINGS THROUGH THE REGION WITH GOOD SLUG OF
MOISTURE AND BRIEF GUSTY WINDS LATE TUE NIGHT AND WED. OVERALL
UPPER LEVEL PATTERN THEN SHIFTS WITH MORE AMPLIFICATION AS LONG
WAVE RIDGE BUILDS TO THE PACIFIC COAST LATE THIS WEEK. RESPONDING
LONG WAVE TROUGHING DIGS THROUGH THE CENTRAL U.S. HEADING EASTWARD
BY NEXT WEEKEND. SOME DETERMINISTIC MODELS SIGNAL COASTAL LOW PRES
DEVELOPMENT SOMETIME NEXT WEEKEND BUT VERY LOW RUN TO RUN
CONSISTENCY.
DETAILS...
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...STRONG LOW PRES MOVES
INTO THE GREAT LAKES AND CENTRAL CANADA TUE NIGHT/WED...WITH
ASSOCIATED COLD FRONT MOVING QUICKLY E WED AFTERNOON/EVENING.
EXPECT PRECIP TO ARRIVE ACROSS THE REGION AFTER MIDNIGHT TUE
NIGHT. WITH SOME INLAND TEMPS CLOSE TO OR BELOW FREEZING AT THE
ONSET OF THE PRECIP...WILL SEE PATCHY LIGHT FREEZING RAIN IN SOME
LOCATIONS ESPECIALLY IN THE LOWER VALLEYS WHERE THE SHALLOW COLD
AIR WILL BE BRIEFLY TRAPPED. S-SE WINDS WILL INCREASE
OVERNIGHT...BRINGING MILDER TEMPS SO ANY PATCHY FREEZING RAIN WILL
CHANGE OVER TO RAIN BY AROUND 12Z WED. WITH ANY FREEZING
RAIN...MAY NEED TO HOIST ADVISORIES MAINLY ACROSS N CENTRAL AND
WESTERN MA. WILL MONITOR.
WILL SEE STEADY RAINFALL WITH A FEW EMBEDDED HEAVY SHOWERS AS THE
FRONT APPROACHES. HAVE NOTED VERY STRONG LOW LEVEL JET JUST ABOVE
THE SURFACE...UP TO 50-60 KT AT BOTH H925 AND H85 AND 50 KT AT H7.
HOWEVER...INVERTED MODEL SOUNDINGS ALONG WITH LOW LAPSE RATES
INDICATE RATHER STABLE CONDITIONS SO SHOULD NOT MIX DOWN EXCEPT
WITH ANY HEAVIER SHOWERS AROUND MIDDAY INTO THE AFTERNOON. ONLY
LOCATIONS WHERE GOOD LOW LEVEL MIXING SEEN WAS OVER THE EASTERN
WATERS AS WELL AS OUTER CAPE COD. WOULD NOT BE SURPRISED TO SEE
SOME S-SW WIND GUSTS THERE UP TO AROUND 30 KT...POSSIBLY DOWN TO
THE IMMEDIATE S COAST.
SOME MARGINAL INSTABILITY IS ALSO POSSIBLE ALONG THE S COAST
AROUND MIDDAY OR EARLY WED AFTERNOON...SO CAN NOT RULE OUT A
POSSIBLE RUMBLE OF THUNDER OR TWO.
AS FOR TEMPS...WITH GOOD INFLUX OF MILD TEMPS WITH S-SW WINDS IN
PLACE...EXPECT TEMPS TO REACH THE LOWER-MID 50S AT LEAST. COULD BE
A BIT MILDER MAINLY ACROSS E MA INTO RI.
EXPECT THE LOW CLOUDS AND RAIN TO MOVE QUICKLY E AS THE COLD FRONT
PASSES WED AND WINDS SHIFT TO W. MAY SEE BRIEF GUSTY WINDS WITH
THE FRONTAL PASSAGE EARLY WED NIGHT. SOME LEFTOVER LIGHT RAIN MAY
LINGER ALONG THE S COAST THROUGH MOST OF THE NIGHT.
THURSDAY...
WEAK HIGH PRES RIDGE BUILDS ACROSS. COLDER AIR ACROSS WESTERN
AREAS WILL SLOWLY WORK E DURING THE DAY...SO WILL SEE MILD TEMPS
HOLD IN ANOTHER DAY ACROSS E MA/RI INTO NE CT. HIGHS WILL RANGE
FROM THE UPPER 30S TO LOWER 40S WELL INLAND TO NEAR 50 ACROSS THE
COASTAL PLAIN.
THURSDAY NIGHT-FRIDAY...
BIG QUESTIONS IN PLACE WITH STALLED FRONT OFF THE S COAST AND
WEAK WAVES OF LOW PRES THAT MOVE ALONG IT. MODELS TRY TO PUSH THE
PRECIP FIELD BACK TOWARD THE COAST DURING THIS TIMEFRAME...MAINLY
ACROSS THE COASTAL PLAIN. WITH COLDER AIR IN PLACE...MAY SEE
SPOTTY LIGHT RAIN AND/OR SNOW THERE. TIMING AND PLACEMENT OF THIS
PRECIP IS VERY MUCH IN QUESTION SO LOW FORECAST CONFIDENCE DURING
THIS TIMEFRAME.
SATURDAY-SUNDAY...
NOTING THE POSSIBILITY OF LOW PRES DEVELOPMENT OFF THE MID ATLC
COAST SOMETIME FROM LATE SATURDAY THROUGH LATE SUNDAY...AT LEAST
ON 00Z ECMWF OP MODEL RUN. DETERMINISTIC MODEL GUIDANCE CONTINUES
TO HAVE WIDE RANGE IN THEIR RUN TO RUN SOLUTIONS...LIKELY DUE TO
RESOLUTION OF WEAK WAVES THAT WILL DEVELOP ALONG THE FRONT
OFFSHORE. THERE ARE ALSO QUESTIONS AS TO WHETHER ANY PHASING
BETWEEN THE NORTHERN AND SOUTHERN STREAMS WILL OCCUR. MANY TIMING
AND TRACK ISSUES THAT WILL NEED TO BE RESOLVED. VERY LOW
CONFIDENCE CONTINUES.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
TODAY...STILL WATCHING THE POTENTIAL FOR IFR CIGS ACROSS SOUTHEAST
MA. GUIDANCE CONTINUES TO SUGGEST IT...WITH SOME BRIEF SUPPORT
FROM SURFACE OBSERVATIONS AT TIMES. AS OF YET NOT EVEN CLOSE TO
BEING AS PREVALENT AS SOME MODELS WOULD SUGGEST. WILL CONTINUE TO
MONITOR. LOW CONFIDENCE THIS IFR DECK COULD DEVELOP RAPIDLY LATE
TONIGHT.
WITH A COLD FRONT QUICKLY CROSSING THE REGION...EXPECTING MAINLY
VFR CONDITIONS. PATCHY MVFR IN ISOLATED SHOWERS. SOUTHWEST WINDS
CONTINUE. MUCH STRONGER SOUTHWEST WINDS AT 2 KFT LEADING TO A
RISK FOR LLWS THIS MORNING. THIS RISK WILL DIMINISH AS THE CORE OF
THIS LOW LEVEL JET MOVES OFFSHORE BY THIS AFTERNOON. WEST TO
NORTHWEST GUSTS UP TO 25 KT AS THIS COLD FRONT PASSES BY.
TONIGHT...HIGH CONFIDENCE VFR WITH DRY WEATHER. NORTHWEST WINDS
BECOMING LIGHT NORTH.
TUESDAY...HIGH CONFIDENCE VFR. LIGHT NORTH WINDS VEER TO N-NE
DURING THE DAY. WILL SEE INCREASING MID-HIGH CLOUDS LATE
KBOS TERMINAL...ONLY TIMEFRAME OF LOW FORECAST CONFIDENCE IN TAF
IS FROM 12Z-17Z WHEN IFR CIGS MAY BRIEFLY IMPACT LOGAN/S
AIRSPACE. TYPICALLY SW WINDS ENOUGH OF LAND TRAJECTORY TO PRECLUDE
IFR CONDITIONS. KEPT THESE LOWER CLOUDS FEW-SCT AT THIS TIME. MAIN
CORE OF THESE LOWER CLOUDS SHOULD BE SOUTH OF THE TERMINAL.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK /TUESDAY NIGHT THROUGH FRIDAY/...MODERATE CONFIDENCE.
TUESDAY NIGHT THROUGH WEDNESDAY...
CIGS WILL LOWER TO MVFR-IFR FROM W-E. RAIN WILL MOVE INTO WESTERN
AREAS BY AROUND MIDNIGHT THEN QUICKLY SHIFT E OVERNIGHT. MAY SEE
PATCHY -FZRA AT THE START OF THE PRECIP OVERNIGHT TUE NIGHT ACROSS
N CENTRAL AND W MA...BUT SHOULD QUICKLY CHANGE TO RAIN BY AROUND
12Z. MAY SEE SOME EMBEDDED +SHRA DURING WED. BRIEF S-SW WIND GUSTS
UP TO AROUND 30 KT POSSIBLE ALONG S-SE COAST FROM THE LATE MORNING
INTO THE AFTERNOON. LLWS LIKELY WED INTO WED EVENING AS S-SW
WINDS AT 2KFT POSSIBLY UP TO 50 KT.
WEDNESDAY NIGHT...
RAIN SHIFTS E EARLY...BUT SPOTTY -RA MAY LINGER ACROSS CAPE COD
AND THE ISLANDS THROUGH MOST OF THE NIGHT. MVFR-IFR CONDITIONS
WILL IMPROVE FROM W-E AS WINDS SHIFT TO W. SOME LEFTOVER MVFR
CLOUDS MAY LINGER ALONG THE S COAST INTO THE EARLY MORNING HOURS.
THURSDAY-FRIDAY...
MAINLY VFR THU AND FRI. DRY CONDITIONS WITH LIGHT W-NW WINDS
THU...THOUGH PATCHY -RA MAY LINGER ON THE S COAST. NORTHERN FRINGE
OF LOW PRES MAY PUSH -RA BACK TOWARD THE COASTAL PLAIN THU NIGHT-
FRI WITH MVFR CIGS/VSBYS IN PATCHY -RA/-SN POSSIBLE.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...HIGH CONFIDENCE.
A COLD FRONT WILL CROSS THE WATERS THIS AFTERNOON AND EVENING.
SOUTHWEST WINDS WILL VEER WEST-NORTHWEST AS THIS FRONT PASSES BY.
GUSTS UP TO 25 KT POSSIBLE UNTIL THIS FRONT PASSES BY. THE OTHER
STORY WILL BE ROUGH SEAS...FIRST ACROSS THE SOUTHERN COASTAL
WATERS...THEN EXPANDING TO THE EASTERN OUTER COASTAL WATERS BY
THIS AFTERNOON. GOOD VISIBILITY...WITH THE RISK OF A SPOT SHOWER
THIS AFTERNOON AND EVENING.
WINDS AND SEAS DIMINISH TONIGHT INTO TUESDAY...WITH SEAS TAKING
LONGER. SMALL CRAFT ADVISORIES WILL CONTINUE TODAY...THEN
GRADUALLY BE DROPPED TONIGHT INTO TUESDAY.
OUTLOOK /TUESDAY NIGHT THROUGH FRIDAY/...MODERATE CONFIDENCE.
TUESDAY NIGHT...EXPECT LIGHT NE-E WINDS...WHICH WILL INCREASE AS
THEY VEER TO SE-S AFTER MIDNIGHT. GUSTS UP TO AROUND 20 KT TOWARD
DAYBREAK. SEAS BRIEFLY SUBSIDE BELOW 5 FT TUE...THEN BUILD AGAIN
TO AROUND 5 FT TUE NIGHT OVER THE OPEN WATERS AND S SOUNDS.
WEDNESDAY-WEDNESDAY NIGHT...
EXPECT RAIN WITH EMBEDDED HEAVY SHOWERS PUSHING ACROSS THE
WATERS. SOME VSBY RESTRICTIONS POSSIBLE. S WINDS GUSTING UP TO
30-35 KT ON THE EASTERN OUTER WATERS BY LATE WED MORNING THROUGH
WED EVENING...THEN SHOULD DIMINISH. GALES LIKELY. SEAS BUILDING
UP TO 7-10 FT ON THE OPEN WATERS.
RAIN ENDS WED NIGHT...THOUGH SOME PATCHY LIGHT RAIN MAY LINGER ON
THE SOUTHERN WATERS. SW WINDS EARLY WED NIGHT SHIFT TO W AND
DIMINISH. SEAS WILL SLOWLY SUBSIDE...BUT WILL LINGER AOA 5 FT ON
THE OPEN WATERS.
THURSDAY...
EXPECT LIGHT N-NW WINDS DURING THU...WITH GUSTS UP TO 20 KT ON
THE OUTER WATERS. SEAS LINGERING AT AROUND 5 FT THROUGH THE
DAY...THEN WILL SUBSIDE THU NIGHT.
FRIDAY...
N WINDS WILL GENERALLY BE FROM 15-20 KT. MAY SEE GUSTS UP TO 25
KT ON THE OUTER WATERS E AND S OF CAPE COD WHERE SEAS MAY LINGER
AT AROUND 5 FT.
&&
.CLIMATE...
RECORD HIGHS FOR TODAY/MONDAY FEB 1ST...
BOS...66/1989
PVD...64/1989
BDL...67/1989
ORH...61/1989
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ237.
SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR ANZ235.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ250.
SMALL CRAFT ADVISORY UNTIL 10 AM EST TUESDAY FOR ANZ254-255.
SMALL CRAFT ADVISORY UNTIL 8 AM EST TUESDAY FOR ANZ256.
&&
$$
SYNOPSIS...BELK/EVT
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...EVT
AVIATION...BELK/EVT
MARINE...BELK/EVT
CLIMATE...STAFF
AREA FORECAST DISCUSSION
NWS WICHITA KS
1154 PM CST SUN JAN 31 2016
...UPDATED FOR 06Z AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 237 PM CST SUN JAN 31 2016
CURRENTLY HAVE ONE SHORTWAVE APPROACHING THE WESTERN GREAT LAKES
WITH ANOTHER MORE VIGOROUS PIECE OF ENERGY DIGGING OVER
NORTHERN/CENTRAL CA. AT THE SURFACE...A COLD FRONT STRETCHES FROM
NORTHERN IL DOWN INTO NORTHEAST TX.
&&
.UPDATE...
ISSUED AT 917 PM CST SUN JAN 31 2016
THE SIGNIFICANT STORM SYSTEM THAT WILL AFFECT THE PLAINS FOR MON
THRU TUE HAS FINALLY MOVED ON SHORE OF SRN CA. SO ITS FINALLY BEING
SAMPLED BETTER BY UPPER AIR NETWORK AND MODELS. WITH THAT
SAID...LATEST MODEL RUNS AND CURRENT FORECAST ARE ON TRACK. THIS
HAS INCREASED CONFIDENCE IN THE GOING FORECAST...WITH JUST SOME
MINOR TIMING ISSUES. ONE OF THOSE TIMING ISSUES WILL BE THE
INITIAL ONSET OF WIDELY SCATTERED LIGHT PRECIP CHANCES IN THE
MORNING HOURS ON MON. LATEST RAP HI-RES GUIDANCE SUGGESTS PRECIP
MAY BE DELAYED UNTIL MID MORNING MON FOR AREAS WEST OF I-135 AS
LOW LEVELS WILL BE SLOW TO SATURATE. SO HAVE ADJUSTED POPS SOME TO
SLOW POPS UNTIL THE LATE MORNING HOURS. CERTAINLY THINK POPS ARE
LIKELY FOR CENTRAL KS FOR MON AFTERNOON. TIMING OF THE HEAVIEST
SNOW ACROSS NORTH CENTRAL KS STILL LOOKS ON TRACK FOR MON EVENING
THRU TUE MORNING.
KETCHAM
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 237 PM CST SUN JAN 31 2016
POTENT UPPER TROUGH WILL CONTINUE TO DIG OVER THE DESERT SW
TONIGHT AND WILL START TO MOVE OUT ACROSS THE SOUTHERN HIGH PLAINS
MON. GFS AND ECMWF REMAIN CONSISTENT AS THEY HAVE OVER THE LAST
FEW DAYS WHICH DOES LEAD TO SOME CONFIDENCE IN HEAVY SNOW LOCATION
AND TIMING. THE 12Z RUN OF THE NAM HAS STARTED TO TREND SLIGHTLY
NORTH COMPARED TO IT`S PREVIOUS RUNS BUT IS STILL A BIT FURTHER
SOUTH AND COLDER THAN THE GFS AND ECMWF SOLUTIONS.
CURRENTLY EXPECTING PRECIP TO OVERSPREAD WESTERN KS MON...GETTING
INTO OUR CENTRAL KS COUNTIES MON AFTERNOON. THERMAL PROFILES WOULD
SUGGEST THAT TEMPS WILL BE TOO WARM FOR ACCUMULATING SNOW MON
AFTERNOON AS STRONG LOW LEVEL WARM ADVECTION OFFSETS WET BULB
PROCESSES. MON NIGHT STILL LOOKS LIKE WHEN THE BULK OF SNOW WILL
IMPACT CENTRAL KS. CURRENTLY THINK THERE WILL BE AROUND A 12-15
HOUR PERIOD OF SNOW GENERALLY NW OF A KGBD-KSLN LINE WITH CROSS
SECTIONS SUGGESTING AROUND 4-5 HOURS WILL HAVE GOOD LIFT IN THE
DENDRITIC ZONE ALONG WITH SOME SLANTWISE INSTABILITY...RESULTING
IN AROUND 1 INCH PER HOUR RATES. HOWEVER...LOCATIONS JUST TO OUR
NW WILL SEE A MUCH MORE PROLONGED PERIOD OF GOOD SNOW GROWTH
PRODUCTION...RESULTING IN THE HIGHEST SNOW TOTALS WITH THIS
EVENT. THE BETTER FRONTOGENESIS IN A 600-700MB LAYER ALSO
CONTINUES TO REMAIN NORTH OF THE FORECAST AREA. NORTH WINDS
CONTINUE TO LOOK STRONG MON NIGHT INTO TUE...WITH GUSTS IN THE 35
TO 40 MPH RANGE NOT OUT OF THE QUESTION...WHICH SHOULD RESULT IN
SOME BLOWING AND DRIFTING OF SNOW.
SO FOR NOW...WILL GO WITH SNOW TOTALS FAIRLY CLOSE TO WHAT THE
PREVIOUS FORECAST HAD WITH AROUND 9 INCHES OVER FAR NW RUSSELL
COUNTY TAPERING QUICKLY TO LESS THAN 2 INCHES SE OF A LINE FROM
LYONS TO SALINA. FOR NOW WILL UPGRADE THE CURRENT WATCH TO A
WARNING WHICH IS WHERE WE STILL HAVE THE HIGHEST CONFIDENCE IN
AMOUNTS 6 INCHES OR GREATER. WHILE IT`S LIKELY THERE WILL BE AN
ADVISORY FOR A FEW COUNTIES SOUTH OF THE WARNING...WANT TO ALLOW
SOME LEEWAY FOR FUTURE SHIFTS TO ADD A COUNTY OR 2 TO THE WARNING
IF THIS STORM SYSTEM CHANGES ITS TRACK SLIGHTLY. BASICALLY WANT TO
AVOID FLIP FLOPPING HEADLINES.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 237 PM CST SUN JAN 31 2016
SNOW SHOULD COME TO AN END TUE EVENING AS THE TROUGH QUICKLY DEPARTS
TO THE NORTHEAST. VERY COLD AIRMASS IS THEN FORECAST TO SPILL
ACROSS THE PLAINS WITH HIGHS WED NOT EXPECTED TO GET MUCH ABOVE
FREEZING FOR MUCH OF THE AREA. WE THEN GET INTO NW FLOW ALOFT
ACROSS THE PLAINS WITH A SERIES OF FAST MOVING IMPULSES DIVING
ACROSS THE FORECAST AREA. SO WOULDN`T BE SHOCKED IF FLURRIES OR
LIGHT SNOW IS INSERTED WED OR THU NIGHT INTO FRI...BUT CONFIDENCE
IS HIGH THAT WE ARE NOT LOOKING AT A SIGNIFICANT SNOW EVENT.
LAWSON
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1153 PM CST SUN JAN 31 2016
WINDS WILL GRADUALLY SHIFT TO THE NORTHEAST AND EAST TONIGHT AS
THE WEAK RIDGE MOVES QUICKLY ACROSS THE AREA TONIGHT.
THE WIND SHIFT TO THE EAST WILL BE IN RESPONSE TO A SIGNIFICANT
STORM SYSTEM MOVING INTO THE SOUTHERN ROCKIES TONIGHT INTO EARLY
MON. AS THIS SYSTEM APPROACHES THE PLAINS...EXPECT CEILINGS TO
GRADUALLY DECREASE IN HEIGHT FOR THE MORNING HOURS ON MON....WITH
SATURATION IN THE MID LAYERS INCREASING ENOUGH FOR A LIGHT RAIN
CHANCE BY AROUND 16Z/MON FOR THE KRSL AND KGBD TAF SITES. EXPECT A
LOWERING OF THE CEILINGS TO MVFR FOR BOTH KRSL AND KGBD AS
SATURATION CONTINUES TO INCREASE BY AROUND 21Z/MON.
WILL SEE THE DETERIORATING CELLING TREND CONTINUE INTO MON EVENING
WITH CIGS DROPPING TO MVFR FOR MOST LOCATIONS AFTER 00Z/TUE. SHOWERS
WILL BECOME PREVAILING AT MOST LOCATIONS DURING THE EVENING HOURS.
COULD EVEN SEE SOME RUMBLES OF THUNDER ACROSS SOUTHERN KS...SO WILL
INCLUDE A VCTS FOR THE KICT/KHUT AND KCNU TAFS. WILL ALSO INCLUDE
THE MENTION OF A RAIN/SNOW MIX FOR KRSL AS COLDER AIR BEGINS TO TURN
THE RAIN OVER TO SNOW.
KETCHAM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 33 51 32 36 / 10 30 80 40
HUTCHINSON 31 48 31 34 / 10 50 80 50
NEWTON 32 48 32 36 / 10 40 80 50
ELDORADO 33 51 34 40 / 10 30 80 30
WINFIELD-KWLD 32 54 37 41 / 10 20 70 20
RUSSELL 29 41 27 29 / 10 80 100 90
GREAT BEND 29 42 28 30 / 10 80 90 70
SALINA 31 44 30 32 / 10 60 90 70
MCPHERSON 31 47 31 34 / 10 50 80 60
COFFEYVILLE 34 57 43 51 / 10 10 70 20
CHANUTE 32 53 41 46 / 10 10 80 30
IOLA 32 52 40 45 / 10 10 80 40
PARSONS-KPPF 33 55 42 48 / 10 10 70 30
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM 6 PM MONDAY TO 6 PM CST TUESDAY FOR
KSZ032-033-047.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
324 AM EST MON FEB 1 2016
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 324 AM EST MON FEB 1 2016
THE AREA WILL SEE A QUIET AND CONTINUED MILD DAY TODAY AFTER THE
RAIN ON SUNDAY. THIS WILL REMAIN BRIEF AS WE WILL SEE A
STRENGTHENING STORM SYSTEM MOVE TOWARD THE AREA ON TUESDAY AND
TUESDAY EVENING. THIS WILL BRING SOME LIGHT SNOW TO THE AREA
INITIALLY...AND THEN EVENTUALLY CHANGE OVER TO RAIN WITH A MIX
POSSIBLE UP NORTH DURING THE TRANSITION.
COLDER AIR WILL SETTLE IN ACROSS THE AREA DURING THE DAY ON
WEDNESDAY...HELPING TO CHANGE ANY LEFT OVER RAIN SHOWERS OVER TO
SNOW SHOWERS. CHANCES FOR SNOW SHOWERS WILL REMAIN POSSIBLE THEN
THROUGH THE END OF THE WEEK WITH COOLER AIR EXPECTED.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 324 AM EST MON FEB 1 2016
THE FORECAST GENERALLY REMAINS THE SAME REGARDING THE UPCOMING STORM
SYSTEM MOVING THROUGH ON TUE AND TUE NIGHT. THE ONLY NOTICEABLE
CHANGE WAS THAT WE HAVE ADDED A CHC OF SOME FREEZING RAIN UP NORTH
LATE TUE AFTERNOON. THIS LIGHT ICING POSSIBLE AND BURST OF SNOW ON
THE LEADING EDGE OF THE SYSTEM LOOK TO PRODUCE THE MOST IMPACTS
REGARDING THE STORM FOR SW LOWER MI.
RAIN AND SNOW HAS MOVED OUT OF THE CWFA THIS MORNING...AND WE SHOULD
REMAIN DRY ACROSS THE CWFA AT LEAST UNTIL AROUND DAYBREAK TUE
MORNING. SOME CLEARING IS TRYING TO MOVE IN THIS MORNING...HOWEVER
LOW CLOUDS ARE REFORMING WITH THE MOIST ATMOSPHERE AND WIND...AND
MORE CLOUDS WILL DROP SOUTH INTO THE AREA THIS AFTERNOON.
THE FIRST CHC OF PCPN WITH THE WELL ADVERTISED STORM WILL COME
TOWARD DAYBREAK TUE MORNING. THIS WILL COME IN THE FORM OF SOME
FLURRIES/VERY LIGHT SNOW ASSOCIATED WITH A LEAD WAVE COMING IN AHEAD
OF THE MAIN WAVE. THE ATMOSPHERE WILL BE FAIRLY DRY INITIALLY WHICH
WILL LIMIT ANY SNOW AMOUNTS THAT WOULD FALL WITH THIS.
THE MAIN THRUST OF PCPN WILL COME DURING THE AFTERNOON AND EARLY
EVENING HOURS ON TUE. THIS IS WHEN WE WILL SEE THE MAIN SURGE OF
MOISTURE MOVE IN FROM THE SOUTH. PCPN SOUTH OF I-96 WILL TRANSITION
QUICKLY TO RAIN FROM SNOW BY EARLY AFTERNOON AS THE SFC WILL BE
ABOVE FREEZING BY THEN...AND THE MELTING LAYER WILL BECOME QUITE
LARGE VERY QUICKLY. THIS WILL THEN PROGRESS STEADILY NORTH THROUGH
THE EVENING HOURS.
AREAS UP NORTH WILL SEE A LONGER POTENTIAL FOR SNOW WHICH WILL ALLOW
ACCUMS TO BE A LITTLE BIT BETTER. THE HEAVY ACCUMULATIONS ARE
EXPECTED TO REMAIN NORTH OF THE CWFA. NORTHERN AREAS WILL THEN SEE A
SHORT WINDOW FOR SOME SLEET AND FREEZING RAIN WITH TEMPS CLOSER TO
FREEZING THAT WILL WET BULB DOWN A LITTLE AS TEMPS ALOFT GO ABOVE
FREEZING. WE ARE NOT EXPECTING SIGNIFICANT ICE...HOWEVER A TENTH OR
SO STILL COULD CAUSE SOME ISSUES UNTIL TEMPS GO ABOVE FREEZING THERE
MID EVENING.
THE DRY SLOT WILL WORK INTO THE AREA BY MID EVENING...CUTTING BACK
THE PCPN INTENSITY AND POSSIBLY TURNING PCPN OVER THE DRIZZLE. PCPN
CHCS WILL THEN PICK UP LATE ACROSS THE NW AS THE MAIN WAVE MOVES
ACROSS THAT AREA AND MOISTURE DEPTH WILL INCREASE. WE EXPECT THAT
JUST ABOUT EVERYONE SHOULD REMAIN RAIN THROUGH 12Z WED. AFTER 12Z
WED...THE COLDER AIR WILL PUSH EAST ACROSS THE AREA...CHANGING RAIN
TO SNOW. BY LATE ON WED...SOME LAKE EFFECT WILL BE POSSIBLE FOR NW
FLOW FAVORED AREAS AS H850 TEMPS DROP BELOW -10C GIVING DELTA T/S
AROUND 13C OR SO.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 324 AM EST MON FEB 1 2016
THE COMBINATION OF CYCLONIC FLOW THROUGH 700 MB AND AN AIRMASS COLD
ENOUGH FOR LAKE EFFECT WILL SUPPORT SNOW SHOWERS WED NIGHT INTO THU.
WILL FEATURE HIGHEST POPS AND THE POTENTIAL FOR MINOR ACCUMULATIONS
GENERALLY WEST OF A BATTLE CREEK TO BIG RAPIDS LINE.
WARM AIR ADVECTION SETS UP FOR THU NIGHT INTO FRI. WE MAY SEE A
SOUTHWEST FLOW EVENT TRY TO DEVELOP...WHICH WOULD LEAD TO AN
INCREASE IN THE SNOW SHOWER ACTIVITY FOR THE LUDINGTON REGION.
OVERALL THE SET UP IS MARGINAL AND AT THIS POINT I WILL ONLY FEATURE
SOMEWHAT HIGHER POPS FOR THE NORTHWEST COUNTIES.
A STRONGER MID LEVEL WAVE IS SHOWN TO ARRIVE FOR FRIDAY NIGHT INTO
SATURDAY. THE COMBINATION OF THE DGZ BECOMING SATURATED AND LIFT
ASSOCIATED WITH THIS WAVE SUPPORTS RELATIVELY HIGH POPS FOR THIS
PERIOD ESPECIALLY THE NORTHWEST COUNTIES WHERE THE LOW LEVEL
CONVERGENCE WILL BE MAXIMIZED.
HARD TO BE REAL CONFIDENT ON THE FORECAST FOR SUNDAY OR MONDAY.
OVERALL THE TREND HAS BEEN TO FAVOR NUDGING THE ARCTIC AIRMASS
FURTHER NORTH AND EAST AHEAD OF THE NEXT WAVE. I NOTICED THE LATEST
00Z HIGH RES EURO RUN PUSHES THE 925 MB TEMP TO POSITIVE VALUES.
THIS WOULD FAVOR MORE IN THE WAY OF RAIN SHOWERS. WILL KEEP IT SNOW
SHOWERS AT THIS POINT...BUT WILL NEED TO MONITOR TRENDS CLOSELY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1136 PM EST SUN JAN 31 2016
FOR THE MOST PART IFR CIGS AND IN SOME CASES IFR VSBY PREVAILED AT
ALL OF OUR TAF SITES. SINCE THE COLD FRONT HAS ALREADY COME
THROUGH I WOULD EXPECT SOME CLEARING OF THE LOW CLOUDS BY TOMORROW
AFTERNOON. THE RAP MODEL CONTINUES TO SHOW DENSE FOG OVER OUR
WESTERN CWA TOWARD MORNING. GIVEN THE FORECAST LIGHT WINDS
FORECAST BY MORNING... THIS WOULD NOT BE OUT OF THE QUESTION.
STILL I BELIEVE THE MVFR CIG WILL PREVAIL TOMORROW.
&&
.MARINE...
ISSUED AT 324 AM EST MON FEB 1 2016
WE WILL BE ISSUING A GALE WATCH FOR MUCH OF TUE AND TUE EVENING FOR
THE ENTIRE NEARSHORE WATERS. WINDS WILL RAMP UP SIGNIFICANTLY
IMMEDIATELY AHEAD OF THE LOW BY TUE AFTERNOON AND WILL CONTINUE AND
PEAK TUE EVENING AS THE DRY SLOT PUSHES THROUGH.
&&
.HYDROLOGY...
ISSUED AT 1245 PM EST SUN JAN 31 2016
MINOR FLOODING IS POSSIBLE LATER THIS WEEK... ESPECIALLY IN
LOWLAND AREAS NEAR RIVERS. SOME RIVERS MAY EXCEED BANKFULL DUE TO
SNOW MELT AND A STORM TUESDAY INTO WEDNESDAY. STORM TOTAL
PRECIPITATION OF 0.50-1.00 INCHES IS POSSIBLE. PRECIPITATION IS
STILL EXPECTED TO BE A WINTRY MIX OR PLAIN RAIN. RIVER LEVEL RISES
ARE ESPECIALLY LIKELY FROM MIDWEEK THROUGH NEXT WEEKEND.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...GALE WATCH FOR THE ENTIRE NEARSHORE FROM 15Z TUE THROUGH 04Z
WED.
&&
$$
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...MJS
AVIATION...WDM
HYDROLOGY...EBW
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1243 AM EST MON FEB 1 2016
.UPDATE...
ISSUED AT 952 PM EST SUN JAN 31 2016
WIDESPREAD LGT RAIN HAS EXITED OUT OF EASTERN CWA AS UPPER JET
STREAK AND SHORTWAVE AND ASSOCIATED SFC LOW MOVE EAST. LEFT IN THE
WAKE OF THAT SYSTEM IS WEAK SFC TROUGH OVER LK SUPERIOR WITHIN BROAD
TROUGHING ALOFT. A COUPLE OF VERY WEAK SHORTWAVES MOVING THROUGH IN
THE FLOW ARE TRIGGERING LOOSELY ORGANIZED AREAS OF LGT PRECIP. ONE
IS OVER EASTERN LK SUPERIOR WITH SOME ECHOES SHOWING UP ON THE RADAR
LAST COUPLE HOURS. MOST LIKELY ISOLD SNOW SHOWERS IN THAT BAND.
OTHER AREA OF PRECIP IS OVER NORTHEAST MN. HAVE HAD A COUPLE OBS
WITH LGT SNOW 4SM-7SM WITHIN THOSE SCATTERED RADAR ECHOES. LATEST
HRRR MODEL HAS LATCHED ON TO THE PRECIP CHANCES FOR THE FAR
NORTHEAST CWA. SOUNDINGS WOULD SUGGEST MAINLY SNOW AS MOIST LAYER IS
UP TO 800- 750MB WITH TEMPS IN THAT LAYER -12C OR SO. INCREASED POPS
SLIGHTLY OVER EAST OVERNIGHT AS THIS WAVE/LGT PRECIP MOVES THROUGH.
KEPT THEME OF ISOLD SNOW SHOWERS OR FREEZING DRIZZLE OVER WEST AS
PRECIP OVER NORTHEAST MN MOVES IN WITH HRRR INDICATING TEMPS IN
MOIST LAYER -8C TO -10C.
BOTH OF THESE DISTURBANCES SEEM TO HELP PUSH THE SFC TROUGH OVER LK
SUPERIOR ALONG INTO NORTHERN CWA BY DAYBREAK MON. SLIGHTLY COOLER
BEHIND THIS TROUGH /TEMPS IN MOIST LAYER LOWER THAN -10C BUT NOT BY
MUCH/. DID KEEP ISOLD SNOW SHOWERS FOR LK SUPERIOR SNOW BELTS INTO
MON. ANOTHER SHORTWAVE WORKING THROUGH BY MID MORNING COULD HELP
THESE SNOW SHOWERS ALONG.
FINALLY...CONCERNING THE UPCOMING POTENTIAL WINTER STORM TAKING A
QUICK LOOK AT 00Z NAM THE TIMING IS STILL ON TRACK FOR THE MODERATE
TO HEAVY SNOW TUE AFTN. STRIPE OF HEAVIEST QPF 18Z WED THROUGH 06Z
WED OVER 0.75 INCHES STAYS CENTERED ON FAR SCNTRL...VCNTY OF MNM.
LESSER AMOUNTS UP TO 0.50 EXTEND TO IMT-ESC-ISQ. 21Z SREF MEAN QPF
DURING THE WATCH PERIOD 18Z TUE THROUGH 18Z WED IS SOLID 0.60 INCH
OVER WATCH AREA WITH POCKET OF 0.75 INCHES NCNTRL UPR MICHIGAN
UPSLOPE AREAS. THE TWO MAIN SHORTWAVE PLAYERS ARE JUST PHASING OVER
SOUTHERN CA THIS EVENING AS UPPER JET CARVES OUT TROUGH...SO RAOBS
SHOULD BEGIN TO SAMPLE THIS SYSTEM MORE THOROUGHLY FM HERE ON OUT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 306 PM EST SUN JAN 31 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW ACROSS THE
CONUS. STRONG SRN STREAM SHORTWAVE MOVING ONSHORE OF CA WILL BE THE
FEATURE OF INTEREST FOR A GREAT LAKES WINTER STORM MID WEEK AS IT
TRACKS E...THEN NE. SHORTWAVE OF INTEREST IN SHORT TERM IS NOW
MOVING E ACROSS NORTHERN IOWA. SOME LIGHT PCPN HAS DEVELOPED ACROSS
ERN IA AND MAINLY THE SE HALF OF WI THIS AFTERNOON WITH THIS
FEATURE...AIDED BY UPR DIVERGENCE IN RIGHT ENTRANCE OF UPPER JET NOW
MOVING INTO SRN QUEBEC.
SHORTWAVE OVER IA WILL CONTINUE TO AMPLIFY AS IT MOVES INTO THE WRN
GREAT LAKES THIS EVENING. IN TURN...ASSOC SFC WILL TRACK FROM SRN
LAKE MI TO NEAR THE GEORGIAN BAY THIS EVENING. DEEP LAYER FORCING
SPREADING INTO THE AREA IN ASSOCIATION WITH APPROACHING AMPLIFYING
SHORTWAVE PER MID-LVL Q-VECT CONV AND 700-600 MB FGEN HAS HELPED
SUPPORT SOME LIGHT RAIN OVER SCNTRL AND SE CWA THIS AFTERNOON AS
NOTED ON AREA WEBCAMS.
BASED ON FCST SOUNDINGS AND 1000-850MB THICKNESS FIELD...ANY PCPN
OVER THE SE FCST AREA SHOULD TURN FROM RAIN OR RAIN/SNOW MIX TO
MOSTLY SNOW BY THIS EVENING AS LOW-LEVELS FINALLY BEGIN TO COOL. NOT
EXPECTING MUCH IF ANY SNOW ACCUMULATION (A FEW TENTHS) DUE TO MIX OF
PCPN AND ABOVE FREEZING SFC TEMPS THIS AFTERNOON...EVEN IF PCPN
CHANGES TO ALL SNOW.
TONIGHT...SHORTWAVE FROM NEAR IA MOVES THROUGH THE UPPER GREAT LAKES
WHILE A SFC TROF DROPS S ACROSS LAKE SUPERIOR AND INTO MOST OF NRN
UPPER MI BY 12Z MON. FCST SOUNDINGS SUGGEST MOISTURE DEPTH MAY NOT
BE SUFFICIENT TO REACH SUB -10C TEMPS CONSISTENTLY...ESPECIALLY IN
THE EVENING. SO THERE IS SOME POTENTIAL FOR -FZDZ AT THAT TIME IF
PCPN OCCURS. THE GENERAL LACK OF SYNOPTIC FORCING AND MARGINAL AT
BEST INSTABILITY OVER THE LAKE SUGGESTS NOTHING MORE THAN 20-30 PCT
POPS FOR -SN/-FZDZ ARE WARRANTED NEAR LAKE SUPERIOR TONIGHT. EXPECT
MIN TEMPS IN THE LOWER TO MID 20S.
MONDAY...WEAK WINDS AND SHEAR WITHIN CONVECTIVE BOUNDARY LAYER ALONG
WITH MARGINAL INSTABILITY WILL AGAIN LIMIT POPS TO GENERALLY NO MORE
THAN 30 PCT FOR WNW SNOWBELTS. MAX TEMPS WILL RANGE FROM THE MID TO
UPPER 20S NORTH TO LOWER 30S SOUTH CENTRAL UNDER MOSTLY CLOUDY
SKIES.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 514 PM EST SUN JAN 31 2016
A BROAD MID/UPPER LEVEL TROUGH OVER THE WEST INTO CNTRL CONUS WILL
GIVE WAY TO RIDGING OVER WRN NOAM RESULTING IN NW FLOW INTO THE NRN
LAKES AND INTRUSIONS OF ARCTIC AIR INTO OR JUST TO THE NE OF THE
REGION. THE MAIN WEATHER STORY WILL BE THE WINTER STORM MOVING OUT
OF THE PLAINS INTO THE GREAT LAKES TUE INTO WED.
MONDAY NIGHT...WEAK LOW LEVEL FLOW WILL PREVAIL WITH SFC RIDGING
FROM SASK/MANITOBA THROUGH THE NRN LAKES. WNW 925-850 MB FLOW WITH
850 MB TEMPS AROUND -11C WILL SUPPORT POTENTIAL FOR SOME LIGHT LES.
TUESDAY INTO WEDNESDAY...THE MODELS WERE IN RELATIVELY GOOD
AGREEMENT WITH THE EVOLUTION OF THE WINTER STORM EMERGING FROM THE
PLAINS WITH LITTLE CHANGE FROM PREVIOUS FCSTS. ALTHOUGH THE GFS
REMAINED A BIT FARTHER N WITH THE PATH...OVERALL DIFFERENCES
COMPARED TO THE ECMWF/GEM OR DEPARTURE FROM GFS ENSEMBLE MEAN WAS
RELATIVELY MINOR. HOWEVER...THE MODELS HAVE TRENDED SLIGHTLY FASTER
WITH THE SYSTEM.
AS THE MID LEVEL LOW LIFTS OUT OF THE PLAINS STRONG 700-300 MB
QVECTOR CONV AND 290K-300K ISENTROPIC LIFT WILL SUPPORT A PERIOD OF
HEAVY SNOW...ESPECIALLY FROM 21Z/02-06Z/03. QPF AMOUNTS IN THE 0.4
TO 0.7 INCH RANGE ARE CONSISTENT WITH THE DECENT MOISTURE TRANSPORT
AND 3 G/KG AVAILABLE. EVEN WITH THE STRONGEST LIFT ABOVE THE
DGZ...SLR VALUES IN THE 15/1-20/1 RANGE ARE EXPECTED LEADING TO 12-
18 HOUR SNOWFALL AMOUNTS OF 8 TO 10 INCHES OVER MUCH OF THE CNTRL
CWA...WITH THE HEAVIEST AMOUNTS OVER THE S AND E. SINCE THE WRN CWA
FROM IWD TO CMX WILL BE ON THE WRN SIDE OF THE LARGE SYNOPTIC PCPN
AREA...CONFIDENCE IN REACHING WARNING AMOUNTS WAS LOWER.
ACCORDINGLY...THE POTENTIAL FOR LAKE ENHANCEMENT OVER THE WEST IS
ALSO LOWER...ESPECIALLY DURING THE PORTION OF THE EVENT WITH NE LOW
LEVEL FLOW. SO...THE WINTER STORM WATCH WAS ISSUED FOR BARAGA/IRON
COUNTIES EASTWARD. LAKE AND UPSLOPE FLOW ENHANCEMENT WILL BE LIKELY
INTO N CNTRL UPPER MI AS 850 MB TEMPS FALL TO AROUND -10C BY 06Z/WED
WITH INCREASING NNE WINDS. SNOW TOTALS MAY EXCEED 12 INCHES IN THE
HIGHER TERRAIN WEST OF MARQUETTE. THE HEAVIER SNOW IS EXPECTED TO END
OVER THE SOUTH BY 12Z AND IN THE NORTH BY AFTERNOON AS THE SYNOPTIC
MOISTURE/LIFT DEPART BUT WITH THE WINDS...DRIVING WILL STILL BE
DIFFICULT.
ALTHOUGH THE FCST WINDS ARE NOT EXTREMELY STRONG AND SLIGHTLY LOWER
THAN PRREVIOUS FCSTS...CONSIDERABLE BLSN IS EXPECTED NEAR LAKE
SUPERIOR AND S CNTRL FROM ESC-MNM.
THU-SUN...A FEW CLIPPER SHORTWAVE TROUGHS ARE EXPECTED TO MOVE
THROUGH THE NRN LAKES THAT COULD BRING SOME LIGHT SNOW TO THE CWA.
THERE IS LOW CONFIDENCE IN TIMING/POSITION OF THESE FEATURES AND
IMPACT ON LES. COLD ENOUGH AIR WILL PREVAIL FOR PERIODS OF LES FOR
MAINLY NW FLOW FAVORED LOCATIONS. THE GFS WAS MORE AGGRESSIVE IN
BRINING COLD AIR INTO THE NRN LAKES BY NEXT WEEKEND COMPARED TO THE
ECMWF.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1242 AM EST MON FEB 1 2016
AT CMX...EXPECT MVFR DECK 010-020 TO REMAIN OVERHEAD IN SOME SHAPE
OR FORM THOUGH TODAY WITH NW WINDS AND WEAK COLD AIR ADVECTION AS
TROUGH SLIDES OVER NORTHERN UPPER MICHIGAN. SMALL POTENTIAL FOR SNOW
SHOWERS BUT VSBY SHOULD BE MVFR FOR THE MOST PART.
AT IWD AND SAW...CONDITIONS ARE VFR BUT WILL TREND DOWN TO MVFR
OVERNIGHT INTO TODAY AS INCREASING LOW-LEVEL MOISTURE ARRIVES AS SFC
TROUGH SLIDES ACROSS. COULD BE LIGHT SNOW SHOWERS/FLURRIES AT TIMES
LATE OVERNIGHT INTO TODAY...ESPECIALLY AT IWD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 306 PM EST SUN JAN 31 2016
ATTENTION DURING THIS FCST PERIOD WILL BE FOCUSED ON THE MIDWEEK
PORTION OF THE FCST AS LOW PRES TRACKS FROM THE SRN PLAINS NE ACROSS
THE GREAT LAKES. LOOKS LIKE THE LOW WILL GENERATE A PERIOD OF NE TO
N GALES LATE TUE NIGHT THRU EARLY WED AFTN OVER ALL BUT FAR WRN LAKE
SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM TUESDAY AFTERNOON THROUGH WEDNESDAY
AFTERNOON FOR MIZ004>007-010>014-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...VOSS
LONG TERM...JLB
AVIATION...JLA
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1136 PM EST SUN JAN 31 2016
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 329 PM EST SUN JAN 31 2016
LOW PRESSURE WILL MOVE EAST OF LOWER MICHIGAN THIS EVENING WITH
PRECIPITATION ENDING FROM WEST TO EAST. FAIR WEATHER WILL FOLLOW FOR
MONDAY INTO EARLY TUESDAY...THEN ANOTHER STORM WILL BRING RAIN AND
SNOW FOR TUESDAY AND TUESDAY NIGHT. COLDER WEATHER WITH OCCASIONAL
SNOW SHOWERS CAN BE EXPECTED FOR THE LATTER HALF OF THE WEEK.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 329 PM EST SUN JAN 31 2016
THE STORM TRACK ON TUESDAY AND TUESDAY NIGHT HAS TRENDED A LITTLE
FURTHER NORTH WITH THE LATEST MODEL GUIDANCE AND THIS WAS FOLLOWED
IN THE FORECAST UPDATE TO TREND TO SLIGHTLY LOWER SNOWFALL
AMOUNTS ACROSS THE NORTHERN FORECAST ZONES.
FOR TONIGHT...BACK EDGE OF PRECIP FROM THE CURRENT LOW TRACKING
ACROSS LOWER MICHIGAN SHOULD BE CLEARING THE EASTERN ZONES BY
MIDNIGHT. THERE SHOULD BE SOME SNOW MIXING IN UP NORTH BEFORE IT
ENDS BUT MARGINAL AIR AND SKIN TEMPS SHOULD PREVENT ANY ACCUMS.
QUIET WEATHER FOR MONDAY INTO EARLY TUESDAY BEFORE THE NEXT LOW
EJECTING FROM THE WESTERN LONGWAVE TROUGH ARRIVES. EAST WINDS
SHOULD HOLD ENOUGH COLD AIR IN FOR SOME MIXED PRECIP AT THE START
BUT SFC TEMPS LOOK MARGINAL FOR ANY ICING. DESPITE STRONG
EASTERLY FLOW THE COLD AIR ADVECTION IS RELATIVELY WEAK COMPARED
TO THE 28 DECEMBER STORM...WHICH WAS ABLE TO MAINTAIN SLEET AND
SOME FREEZING RAIN FOR SEVERAL HOURS.
WE WILL CONTINUE TO MONITOR ICING POTENTIAL BUT AT THIS POINT IT
APPEARS SKIN TEMPS WILL BE MARGINAL AND CAA NOT STRONG ENOUGH TO
ACCOUNT FOR MUCH. SNOW SHOULD BE CONFINED TO THE NORTHERN TIER AND
THE HIGHER ELEVATIONS COULD GET 2 TO 4 INCHES.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 329 PM EST SUN JAN 31 2016
FAIRLY UNEVENTFUL FOR MUCH OF THE LONG TERM...HOWEVER A CLIPPER
SYSTEM SHOULD GIVE US SNOW FRIDAY NIGHT AND SATURDAY.
MOISTURE BEHIND THE SYSTEM QUICKLY BECOMES SHALLOW...SO ITS
QUESTIONABLE HOW MUCH LAKE EFFECT WE SEE INITIALLY AS THE DGZ DOES
NOT APPEAR TO BE SATURATED. WILL LOWER POPS A BIT FOR WED WHERE WE
STILL MAY SEE SOME RAIN EARLY IN THE MORNING...GRADUALLY TRANSITING
TO LIGHT LAKE EFFECT SNOW INTO THE AFTERNOON. WEAK SURFACE RIDGING
SHOULD DEVELOP LATE WED NIGHT INTO THURSDAY...DIMINISHING ANY LAKE
EFFECT SNOWS.
LAKE EFFECT STILL LOOKS MORE MINIMAL THAN PREVIOUS RUNS RIGHT INTO
EARLY FRIDAY AS THE SURFACE RIDGE ONLY SLOWLY MOVES EAST. WILL KEEP
POPS IN...BUT WE MAY HAVE TO TRIMMED THEM BACK IF THESE MODEL TRENDS
CONTINUE. THE FLOW LOOKS TO BECOME MORE FAVORABLE FOR LAKE EFFECT
AS WE GET INTO LATE FRIDAY AS A CLIPPER SYSTEM APPROACHES. SW FLOW
LAKE ENHANCEMENT SHOULD KICK IN FRIDAY AFTERNOON OR EVENING.
THE MODELS ARE IN GOOD AGREEMENT SHOWING THE CLIPPER/S SURFACE LOW
STAYING WELL NORTH...OVER THE SUPERIOR REGION. IT DRAGS A FRONT
THROUGH SW MI SATURDAY MORNING WHEN THE SNOW ENHANCEMENT SHOULD
PEAK. ANOTHER SURGE OF COLDER AIR MOVES IN BEHIND THE CLIPPER BY
SATURDAY NIGHT/SUNDAY WHICH SHOULD HELP MAINTAIN LIGHT LAKE EFFECT
SNOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1136 PM EST SUN JAN 31 2016
FOR THE MOST PART IFR CIGS AND IN SOME CASES IFR VSBY PREVAILED AT
ALL OF OUR TAF SITES. SINCE THE COLD FRONT HAS ALREADY COME
THROUGH I WOULD EXPECT SOME CLEARING OF THE LOW CLOUDS BY TOMORROW
AFTERNOON. THE RAP MODEL CONTINUES TO SHOW DENSE FOG OVER OUR
WESTERN CWA TOWARD MORNING. GIVEN THE FORECAST LIGHT WINDS
FORECAST BY MORNING... THIS WOULD NOT BE OUT OF THE QUESTION.
STILL I BELIEVE THE MVFR CIG WILL PREVAIL TOMORROW.
&&
.MARINE...
ISSUED AT 329 PM EST SUN JAN 31 2016
WINDS AND WAVES WILL BE RELATIVELY LIGHT THROUGH MONDAY BUT THERE
WILL BE SOME AREAS OF DENSE FOG AT TIMES TONIGHT.
&&
.HYDROLOGY...
ISSUED AT 1245 PM EST SUN JAN 31 2016
MINOR FLOODING IS POSSIBLE LATER THIS WEEK... ESPECIALLY IN
LOWLAND AREAS NEAR RIVERS. SOME RIVERS MAY EXCEED BANKFULL DUE TO
SNOW MELT AND A STORM TUESDAY INTO WEDNESDAY. STORM TOTAL
PRECIPITATION OF 0.50-1.00 INCHES IS POSSIBLE. PRECIPITATION IS
STILL EXPECTED TO BE A WINTRY MIX OR PLAIN RAIN. RIVER LEVEL RISES
ARE ESPECIALLY LIKELY FROM MIDWEEK THROUGH NEXT WEEKEND.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...JK
AVIATION...WDM
HYDROLOGY...EBW
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
403 AM CST MON FEB 1 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 402 AM CST MON FEB 1 2016
CLEAR SKIES...LIGHT WINDS AND MOIST LOW LEVEL CONDITIONS FROM THE
MELTING ON SUNDAY HAS ALLOWED FOG TO FORM AT MOST LOCATIONS EARLY
THIS MORNING. PATCHY AREAS OF DENSE FOG ARE COMMON ONCE AGAIN THIS
MORNING ACROSS CENTRAL MN AND ALONG HIGHWAY 8 IN WEST CENTRAL WI.
HELPING TO ABATE THE FOG SOME IS AN INCREASE IN LOW CLOUDINESS FROM
NORTHERN AREAS OF THE STATE. THIS MASS OF LOW CEILINGS IS BEING
HANDLED FAIRLY WELL BY THE RAP AND NAM AT 875MB. THIS WOULD BRING
THE CLOUDS SOUTHEAST TODAY ALONG AND NORTH OF THE I-94 CORRIDOR.
HENCE...THE NORTHEAST HALF OF THE CWA WILL SEE THE MOST CLOUDINESS
TODAY WHILE THE SOUTHWEST HALF WILL SEE A GOOD DEAL OF SUNSHINE. IT
WILL BE ANOTHER MILD DAY WITH HIGHS FROM 30 TO 35 DEGREES.
THE MAIN FEATURE TONIGHT IS THE ONSET OF SNOW AHEAD OF THE WINTER
STORM OVER THE SOUTHWESTERN UNITED STATES EARLY THIS MORNING.
CURRENT THINKING IS THAT SNOW WILL OVERSPREAD THE I-90 CORRIDOR IN
THE 09Z-12Z TIME PERIOD WITH CATEGORICAL POPS IN PLACE. SNOW
ACCUMULATION IN THE THAT THREE HOUR WINDOW IS UP TO A HALF INCH. LOW
TEMPERATURES WERE RAISED A LITTLE BIT ACROSS SOUTHERN AREAS OF THE
FA WITH CLOUDINESS INCREASING FASTER WITH LOWS RANGING FROM THE
TEENS IN CENTRAL MN TO THE LOWER AND MIDDLE 20S TO THE SOUTH AND
EAST.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 402 AM CST MON FEB 1 2016
THE MAIN CONCERN IN THE LONG TERM PERIOD IS THE STRONG WINTER STORM
SET TO IMPACT THE UPPER MIDWEST TOMORROW INTO WEDNESDAY. AFTER THE
STORM MOVES THROUGH THE REGION...TEMPERATURES WILL RUN NEAR NORMAL
FOR EARLY FEBRUARY WITH A FEW CLIPPER SYSTEMS BRINGING POPS INTO THE
FORECAST TOWARD THE WEEKEND.
AS FOR THE LATEST INFORMATION ON THE APPROACHING WINTER
STORM...MODEL GUIDANCE CONTINUES TO WAFFLE BACK AND FORTH. THERE
HAD BEEN TWO DISTINCT CAMPS IN TERMS OF THE TRACK OF THE
STORM...WHICH STILL PERSISTED IN THE 00Z PRODUCT SUITE.
THE GFS HAS CONSISTENTLY BEEN ON THE NORTHERN SIDE OF THE VARIOUS
GUIDANCE. THE ECMWF LEANED TO THE NORTHERN ENVELOPE COMPARED TO THE
GEM AND THE NAM WHICH HAD A VERY SOUTHERN SOLUTION. THE 00Z RUN OF
THE NAM CAME IN WITH A SLIGHT NORTHWARD JOG...AS DID THE 06Z RUN.
THE 12Z EC YESTERDAY TOOK THE 0.5" QPF LINE INTO THE TWIN CITIES
METRO...BUT THEN DIALED IT BACK TO CLOSER TO 0.4" WITH THE 00Z RUN.
THE GFS HAS SLIGHTLY MORE QPF THAN THE LATEST EC. A FIRST LOOK AT
WHAT THE HI-RES ARW AND NMM INDICATE CAME IN OVERNIGHT...WITH
STARK DIFFERENCES AMONG THEM AS WELL. WHILE THE NMM INDICATED 0.48"
OF QPF FOR MSP...THE ARW INDICATED JUST 0.08". THE POINT IS...THERE
IS STILL UNCERTAINTY ALONG THE NORTHERN PERIPHERY OF THE HEAVY SNOW
SWATH...THERE WILL BE A TIGHT SNOWFALL GRADIENT AND IT WILL BE VERY
CLOSE TO THE TWIN CITIES METRO AREA. THIS IS WHY THE WATCH PRODUCTS
WERE LEFT IN PLACE FOR NOW. THE 12Z CYCLE OF MODEL GUIDANCE WILL
HOPEFULLY OFFER LESS UNCERTAINTY AND MORE CONFIDENCE TO NAIL DOWN
WHERE ANY WARNINGS NEED TO BE ISSUED. THE TUESDAY AFTERNOON COMMUTE
WILL BE HEAVILY IMPACTED BY THIS STORM.
OVERALL...THIS FORECAST LEANED TOWARD A BLEND OF THE ECMWF AND
GFS...SO SNOW AMOUNTS WERE GENERALLY TWEAKED UPWARD...AND A COUPLE OF
COUNTIES WERE ADDED TO THE WINTER STORM WATCH. AS FOR THE BLIZZARD
WATCH...DECIDED TO HOLD ON TO IT PRIMARILY DUE TO THE GUIDANCE
BACKING OFF SOME ON THE WINDS ACROSS SOUTH CENTRAL MN. ITS STILL
GOING TO BE BREEZY...BUT WE ARE NOT SURE IF BLIZZARD CRITERIA WILL BE
MET AT THIS TIME. THE WINDS LOOK STRONGER IN IOWA...WHICH EXPLAINS
WHY THEY WERE ABLE TO GO AHEAD WITH A BLIZZARD WARNING THERE. COULD
HAVE GONE WINTER STORM WARNING IN SOUTH CENTRAL MN...BUT DIDNT WANT
PEOPLE TO TAKE THEIR GUARD DOWN ABOUT THE POSSIBILITY OF TRUE
BLIZZARD LIKE CONDITIONS IN SOUTH CENTRAL MN. IF THE 12Z GUIDANCE
COMES IN WITH A SLIGHTLY DEEPER SURFACE LOW...TRUE BLIZZARD
CONDITIONS COULD BE REALIZED. REGARDLESS...TRAVEL ALONG THE I-90
CORRIDOR WILL BE TREACHEROUS TOMORROW WITH HEAVY SNOW AND THE
POTENTIAL FOR 6 TO 10 INCHES.
NOT MUCH IN TERMS OF PRECIPITATION IS EXPECTED BEYOND
TOMORROW...WITH TWO WAVES WORKING SOUTHEAST THROUGH CANADA THROUGH
THE END OF THE WEEK...BUT WOULD PRODUCE VERY LIGHT AMOUNTS OF SNOW.
OTHERWISE...SEASONABLE TEMPERATURES ARE EXPECTED...BUT THE ECMWF
DOES INDICATE THE ARCTIC AIR POURING SOUTH INTO OUR REGION EARLY
NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1105 PM CST SUN JAN 31 2016
VFR FOR ALL SITES AT INITIALIZATION /EXCEPT KAXN WHICH HAS ALREADY
SEEN ITS VSBY DROP TO 2SM/. AM STILL EXPECTING ALL SITES TO DROP
TO MVFR-IFR OVERNIGHT FOR BOTH VSBY AND CEILING THRU DAYBREAK
TOMORROW DUE TO LOW STRATUS/FOG...GIVEN THE HIGH AMOUNT OF
GROUND/LLVL MOISTURE IN PLACE. THE LOW CLOUDS ARE LIKELY TO THEN
REMAIN IN PLACE FOR MUCH OF THE DAY MONDAY...EVEN AFTER THE VSBY
HAS IMPROVED. WINDS WILL BE W/NW AOB 7 KTS THRU THE PERIOD.
KMSP...CONFIDENCE REMAINS FAIRLY HIGH IN LOW CLOUD DEVELOPMENT
OVERNIGHT...PARTICULARLY THRU THE MORNING PUSH WITH IFR CEILINGS
AND MVFR VSBY. PRECIPITATION IS NOT EXPECTED...BUT SHOULD BR TURN
MORE INTO A FG SCENARIO...DEPOSITION FROM THE FOG COULD CREATE
SLICK PAVEMENT /IF UNTREATED/ GIVEN THAT TEMPS WILL DROP INTO THE
20S. VSBYS ARE EXPECTED TO IMPROVE BY LATE MRNG BUT LOW
CEILINGS...POTENTIALLY BELOW 1700 FT...WILL LIKELY LINGER THRU
THE AFTN.
/OUTLOOK FOR KMSP/
TUE...VFR MORNING. MVFR/-SN AFTERNOON. WIND NE 10-20 KTS.
TUE NIGHT...MVFR/-SN WITH IFR/LIFR SN POSSIBLE. WIND N 20G35KT.
WED...VFR. WIND NW 15G25KT.
THU...VFR. SLGT CHC MVFR IN -SN. SW WIND BCMG WNW 5-10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WATCH FROM TUESDAY MORNING THROUGH LATE TUESDAY
NIGHT FOR WIZ016-024>028.
MN...BLIZZARD WATCH FROM TUESDAY MORNING THROUGH LATE TUESDAY NIGHT
FOR MNZ082>085-091>093.
WINTER STORM WATCH FROM TUESDAY MORNING THROUGH LATE TUESDAY
NIGHT FOR MNZ070-074>078.
&&
$$
SHORT TERM...RAH
LONG TERM...SPD
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS DULUTH MN
348 AM CST MON FEB 1 2016
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 348 AM CST MON FEB 1 2016
THE FOCUS IS ON THE WINTER STORM SYSTEM EXPECTED TO AFFECT THE
UPPER MIDWEST AND WESTERN GREAT LAKES REGION TUESDAY AND TUESDAY
NIGHT. THERE ARE STILL NOTABLE DIFFERENCES IN THE MODELED TRACKS
OF THE LOW. THE 00Z GFS AND 00Z ECMWF HAVE MORE NORTHERLY ROUTES
THROUGH NW ILLINOIS AND SE WISCONSIN...BUT THE 00Z NAM AND
00Z CANADIAN HAVE MORE SOUTHERLY ROUTES TOWARDS NORTHERN INDIANA
OR FAR SOUTHERN LAKE MICHIGAN. THE NORTHERLY ROUTE WOULD AFFECT
THE NORTHLAND MORE SO THAN THE SOUTHERLY ROUTE. USED A BLEND OF
ALL FOUR MODELS...AND ALSO THE 21Z SREF. THE RESULT INCREASED PCPN
CHANCES FOR THE SE FORECAST AREA. THE LATEST FORECAST HAS HEAVY
SNOW...ABOUT 6 TO 8 INCHES...FOR THE SOUTHEASTERN HALF OF PRICE
COUNTY...SO ISSUED A WINTER STORM WATCH FOR THE COUNTY. THE DAY
SHIFT WILL NEED TO CONSIDER ISSUING A WARNING FOR PRICE COUNTY IF
CONFIDENCE IN MORE THAN 6 INCHES OF SNOW INCREASES...AND ALSO
CONSIDER ADVISORIES FOR OTHER PARTS OF NW WISCONSIN FOR THE LIKELY
MODERATE SNOWFALL.
RELATIVELY QUIET WEATHER IS EXPECTED TODAY AND TONIGHT. A VERY
SUBTLE TROUGH/COLD FRONT STRETCHED ACROSS THE NORTHLAND EARLY THIS
MORNING AND WILL CONTINUE TO DO SO TODAY. THERE COULD BE EARLY
MORNING FOG...PRIMARILY ACROSS THE SOUTHERN FORECAST AREA. A WEAK
SHORTWAVE IN NORTH DAKOTA WILL MOVE THROUGH THE NORTHLAND TODAY.
THE SUBTLE EFFECTS FROM THE SHORTWAVE AND TROUGH SHOULD HELP
PRODUCE CLOUDY SKIES AND COULD PRODUCE VERY LIGHT SNOWFALL ACROSS
THE NORTHERN FORECAST AREA. THE CLOUDY SKIES WILL LIKELY LINGER
THROUGH TONIGHT.
MEANWHILE...AN UPPER LEVEL LOW WILL BE MOVING ACROSS THE SOUTHERN
ROCKY MOUNTAINS TODAY...AND IT IS EXPECTED TO DEVELOP A LOW
PRESSURE SYSTEM NEAR FAR SE COLORADO LATER TODAY. THE LOW WILL
THEN LIFT THROUGH THE PLAINS TOWARDS THE GREAT LAKES TONIGHT AND
TUESDAY. THIS WINTER STORM SYSTEM WILL AFFECT MUCH OF THE UPPER
MIDWEST AND PARTS OF THE WESTERN GREAT LAKES WITH SNOW. THE LOW
WILL LIKELY TRACK TOWARDS CENTRAL AND SOUTHERN LAKE
MICHIGAN...REACHING THE LAKE TUESDAY EVENING. THE MORE NORTHERN
THE TRACK...THE MORE THE STORM WILL AFFECT PARTS OF THE NORTHLAND.
AT THIS TIME...IT LOOKS LIKE THE STORM WILL SNOW TO AS FAR AS NW
WISCONSIN. THE SNOW SHOULD SPREAD INTO NW WISCONSIN TUESDAY
AFTERNOON...PEAK IN INTENSITY DURING THE LATE AFTERNOON AND
EVENING...AND GRADUALLY TAPER OFF EARLY WEDNESDAY. MUCH OF NW
WISCONSIN IS CURRENTLY FORECAST LIGHT TO MODERATE SNOWFALL
AMOUNTS...AND HEAVY SNOWFALL OF MORE THAN 6 INCHES IS POSSIBLE FOR
PARTS OF PRICE COUNTY. AREAS OF NE MINNESOTA COULD GET A
DUSTING...INCLUDING THE TWIN PORTS...AND THE INTERSTATE 35
CORRIDOR THROUGH PINE COUNTY COULD GET 1 TO 2 INCHES. THE SNOW
WILL BE ACCOMPANIED BY 10 TO 15 MPH COLD NORTHERLY WINDS...WHICH
WOULD LOWER THE VISIBILITY.
THERE WILL BE A COOLING TREND OVER THE NEXT COUPLE DAYS AND
BEYOND. TODAY SHOULD SEE HIGHS RANGE FROM THE UPPER 20S ACROSS THE
NORTH TO THE LOWER 30S ACROSS THE SOUTH. HIGHS ON TUESDAY SHOULD
RANGE FROM THE LOW TO UPPER 20S.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 348 AM CST MON FEB 1 2016
THE SFC LOW MOVES INTO QUEBEC BY 00Z THURSDAY. THIS ALLOWS HIGH
PRESSURE TO BRIEFLY AFFECT THE FORECAST AREA. HOWEVER...THERE WILL
BE AN OPPORTUNITY FOR SOME LAKE EFFECT SNOW ALONG THE SOUTH SHORE
WEDNESDAY. THE FLOW WILL BE WNW WHICH WILL MEAN HAVING SOME LOW
POPS OVER BAYFIELD COUNTY AS WELL AS THE GOGEBIC RANGE AND EVEN
INLAND AS FAR SOUTH AS PRICE COUNTY IN THE MORNING. IN THE
AFTERNOON...DRIER AIR BEGINS TO WORK ITS WAY THROUGH NW WI. THE
WIND IN THE 1000-900MB LAYER BEGINS TO TURN A BIT MORE WESTERLY.
WILL HAVE POPS MAINLY OVER IRON COUNTY WI AS A RESULT. THE HIGH
PRESSURE REMAINS IN CHARGE WEDNESDAY NIGHT. HOWEVER...AN UPPER
LONG WAVE TROF MOVES INTO THE REGION. EMBEDDED PIECES OF ENERGY
WILL MOVE THROUGH THE TROF AND BRING AN AREA OF LIGHT SNOW INTO NE
MN...MAINLY WEST OF HIGHWAY 53. WITH DEEP MOISTURE LACKING...ONLY
SMALL POPS WERE USED. THIS LONG WAVE TROF DRIFTS INTO THE WESTERN
GREAT LAKES ON THURSDAY. WILL MAINTAIN THE SMALL POPS FOR LIGHT
SNOW. A BREAK FROM THE LIGHT SNOW ARRIVES THURSDAY NIGHT AS THE
TROF DEPARTS AND SFC RIDGING COVERS THE AREA. ON FRIDAY...THE
MODELS AGREE ON THE NEXT LONG WAVE TROF TO MOVE OVER THE REGION.
HOWEVER...THEY DISAGREE ON THE EVOLUTION AND TRACK OF A SFC LOW
AND ITS AFFECT ON THE REGION. HAVE LOW POPS AS A RESULT OF THIS
DISAGREEMENT. THIS PERSISTS ON FRIDAY NIGHT AS THE ECMWF MOVES THE
TROF EAST OF THE AREA AND SFC RIDGING TO COVER THE NORTHLAND.
WHILE THE GFS ALLOWS SFC RIDGING...IT DROPS A COLD FRONT INTO THE
AREA WITH LIGHT SNOW. BLENDED THE SOLUTIONS FOR POPS. SOME LAKE
EFFECT SNOW SHOWERS SHOULD DEVELOP LATE FRIDAY NIGHT ALONG THE
SOUTH SHORE WITH A FAVORABLE WIND/FETCH/CAA. A VORTICITY MAXIMA
SWINGS THROUGH THE FORECAST AREA ON SATURDAY. STRENGTH OF THIS
MAXIMA IS HANDLED DIFFERENTLY BY THE MODELS AS WELL AS
SPEED/LOCATION. HAVE SMALL POPS AS A RESULT. A TRANSITION TO A
RATHER SNOWY PERIOD BEGINS SATURDAY NIGHT THAT LASTS THROUGH
SUNDAY. HOWEVER...THERE ARE TIMING ISSUES AS WELL AS
DEPTH/STRENGTH OF SFC LOW DEVELOPMENT. USED A BLENDED APPROACH TO
POPS TO ACCOUNT FOR THESE ISSUES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1140 PM CST SUN JAN 31 2016
A WEAK TROUGH STRETCHING FROM EAST TO WEST ACROSS FAR NORTHERN
MINNESOTA WILL DROP SOUTH TONIGHT. CONVERGENCE ALONG THIS FEATURE
WAS RATHER WEAK...BUT ANOTHER SHORTWAVE WILL MOVE THROUGH IN WNW
FLOW ALOFT. THESE FEATURES AND LOW LEVEL MOISTURE WILL BE ENOUGH
TO SQUEEZE OUT SOME FLURRIES/BRIEF SNOW SHOWERS IN SPOTS OVERNIGHT
INTO MONDAY.
MVFR CEILINGS HAVE BEEN SPREADING SLOWLY SOUTHEAST...AND THE
LATEST RAP CONTINUES THIS TREND. KINL/KHIB/KHYR WERE ALL REPORTING
VFR CONDITIONS...BUT THEY SHOULD ALL GO TO MVFR OVERNIGHT...AND
POSSIBLY IFR AT TIMES. THE BEST CHANCE FOR IFR CONDITIONS IN FOG
WILL BE AT KHYR WHERE SKIES WERE CLEAR AS OF 0530Z WITH A LOW
TEMP/DEWPOINT DEPRESSION. FOG WILL BE POSSIBLE ELSEWHERE AS WELL
INTO MONDAY MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 30 18 26 8 / 10 10 30 30
INL 25 5 19 -1 / 10 10 0 0
BRD 32 18 26 9 / 10 0 10 10
HYR 34 18 29 15 / 10 0 70 70
ASX 31 19 29 17 / 0 0 60 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WATCH FROM TUESDAY AFTERNOON THROUGH LATE TUESDAY
NIGHT FOR WIZ009.
MN...NONE.
LS...NONE.
&&
$$
SHORT TERM...GROCHOCINSKI
LONG TERM...GSF
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
1140 PM CST SUN JAN 31 2016
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 352 PM CST SUN JAN 31 2016
RELATIVELY QUIET WEATHER EXPECTED FOR THE NEXT 24 HOUR WITH A VERY
WEAK TROUGH AXIS/COLD FRONT DRAPED ACROSS THE AREA. THIS FEATURE IS
CURRENTLY DRAPED ALONG THE CANADIAN BORDER...AND SHOULD SLOWLY SAG
SOUTH AND CONTINUE TO WEAKEN OVERNIGHT TONIGHT AND MONDAY. A VERY
WEAK SHORTWAVE WILL RIPPLE THROUGH THE NORTHWEST UPPER LEVEL FLOW
TONIGHT...AND I EXPECT IT TO INCREASE CLOUD COVER AND BRING SOME
VERY SMALL CHANCES FOR LIGHT SNOW NEAR THE TROUGH AXIS...SO HAVE
CARRIED SOME SMALL POPS TONIGHT. HOWEVER...AM NOT TERRIBLY EXCITED
ABOUT THIS AND HAVE KEPT BOTH POPS AND QPF/SNOW AMOUNTS SMALL. THE
CLOUD COVER SHOULD KEEP TEMPS IN THE TEENS AND LOW 20S...THOUGH
THERE IS SOME POTENTIAL FOR LOWER TEMPS SHOULD THE CLOUD COVER NOT
THICKEN UP MUCH. MONDAY WE SHOULD HAVE A BIT MORE CLOUD COVER WITH
THE TUESDAY-WEDNESDAY SYSTEM DEVELOPING OUT OVER THE PLAINS AND
SPREADING CIRRUS OUR WAY. THE EXTRA CLOUD COVER SHOULD KEEP TEMPS
DOWN A LITTLE...SO HAVE GONE WITH COOLER TEMPS THAN TODAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 352 PM CST SUN JAN 31 2016
THE LONG TERM PERIOD IS SHAPING UP TO BE A STORMY ONE FOR MUCH OF
THE WESTERN GREAT LAKES REGION. MONDAY NIGHT LOOKS QUIET ACROSS THE
REGION...WITH SOME LINGERING LAKE EFFECT SNOW SHOWERS INTO THE
EVENING ACROSS THE GOGEBIC RANGE AREA. THE MODELS ARE COMING INTO
BETTER AGREEMENT CONCERNING THE EVOLUTION OF THE UPCOMING WINTER
STORM THAT WILL MOVE INTO EASTERN NEBRASKA BY 12Z TUESDAY. SNOW IS
EXPECTED TO SPREAD INTO MUCH OF SOUTHERN MINNESOTA AND CENTRAL AND
NORTHERN WISCONSIN ON TUESDAY...WITH STRONG WINDS LOCALLY HEAVY
SNOW. AT THIS POINT...IT LOOKS LIKE THE BEST POTENTIAL FOR UP TO A
HALF FOOT OF SNOW WILL BE IN PORTIONS OF PRICE COUNTY WISCONSIN. THE
GFS IS FASTER IN CARRYING THE SYSTEM NORTHEAST OF THE GREAT
LAKES...BUT OVERALL THEY ARE STARTING TO COME INTO PRETTY DECENT
AGREEMENT. SNOWFALL AMOUNTS ACROSS THE AREA WILL PROBABLY RANGE FROM
NO ACCUMULATION ACROSS MUCH OF NORTHEASTERN MINNESOTA...WITH SOME
LIGHT ACCUMULATION ACROSS EAST CENTRAL MN...THE TWIN PORTS AND THE
NORTH SHORE...TO AS MUCH AS 5 TO 6 INCHES IN PRICE COUNTY.
CONTEMPLATED A WINTER STORM WATCH FOR THAT COUNTY...BUT IT STILL HAS
THE POTENTIAL TO GO THE WAY OF AN ADVISORY FOR THAT AREA. NO MATTER
WHAT...WE SHOULD SEE STRONG WINDS...AND SNOW ACROSS ALL OF NW WI. A
WEAKER SHORTWAVE WILL SWOOP DOWN ON THE CWA WEDNESDAY NIGHT AND
THURSDAY...BRINGING SOME LIGHT SNOW TO THE REGION. THE NORTHWEST
FLOW WILL MAINTAIN ITSELF THROUGHOUT THE REMAINDER OF THE LONG TERM
PERIOD...AS A MORE MERIDIONAL FLOW DEVELOPS ACROSS THE GREAT LAKES.
TEMPS WILL BE COOLER THAN NORMAL FOR THIS TIME OF YEAR...WITH HIGHS
RANGING FROM THE SINGLE DIGITS TO THE 20S...AND LOWS VARYING
CONSIDERABLY THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1140 PM CST SUN JAN 31 2016
A WEAK TROUGH STRETCHING FROM EAST TO WEST ACROSS FAR NORTHERN
MINNESOTA WILL DROP SOUTH TONIGHT. CONVERGENCE ALONG THIS FEATURE
WAS RATHER WEAK...BUT ANOTHER SHORTWAVE WILL MOVE THROUGH IN WNW
FLOW ALOFT. THESE FEATURES AND LOW LEVEL MOISTURE WILL BE ENOUGH
TO SQUEEZE OUT SOME FLURRIES/BRIEF SNOW SHOWERS IN SPOTS OVERNIGHT
INTO MONDAY.
MVFR CEILINGS HAVE BEEN SPREADING SLOWLY SOUTHEAST...AND THE
LATEST RAP CONTINUES THIS TREND. KINL/KHIB/KHYR WERE ALL REPORTING
VFR CONDITIONS...BUT THEY SHOULD ALL GO TO MVFR OVERNIGHT...AND
POSSIBLY IFR AT TIMES. THE BEST CHANCE FOR IFR CONDITIONS IN FOG WILL
BE AT KHYR WHERE SKIES WERE CLEAR AS OF 0530Z WITH A LOW
TEMP/DEWPOINT DEPRESSION. FOG WILL BE POSSIBLE ELSEWHERE AS WELL
INTO MONDAY MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 22 30 15 24 / 20 20 10 10
INL 13 24 4 16 / 20 20 10 0
BRD 21 31 16 24 / 10 10 0 10
HYR 23 31 17 28 / 10 10 0 60
ASX 24 32 18 27 / 20 20 10 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
SHORT TERM...LE
LONG TERM...DAP
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1040 PM MST SUN JAN 31 2016
UPDATED AVIATION SECTION
.DISCUSSION...
UNSTABLE NORTHWEST FLOW ALOFT, COLD AIR ALOFT, AND
WEAK SHORT WAVE ENERGY PASSING OVER THE AREA, CONTINUES TO GENERATE
AREAS OF VERY LIGHT SNOW. AREAL COVERAGE OF THE SNOW HAS DECREASED
SO, BASED ON HRRR ANALYSIS, HAVE LOWERED POPS FOR A PORTION OF NORTH
CENTRAL MONTANA OVERNIGHT. ISOLATED TO SCATTERED SNOW SHOWERS SHOULD
PERSIST OVERNIGHT NORTH AND EAST OF GREAT FALLS WITH SNOW
ACCUMULATIONS GENERALLY LESS THAN ONE-HALF INCH OVER THE PLAINS.
REMAINDER OF CURRENT FORECAST DETAILS LOOK GOOD INCLUDING
TEMPERATURES.
&&
.AVIATION...
UPDATED 0540Z.
UNSTABLE NORTHWEST FLOW ALOFT AND AN UPPER LEVEL DISTURBANCE PASSING
OVER THE AREA WILL CONTINUE TO GENERATE ISOLATED TO SCATTERED SNOW
SHOWERS. SNOW AMOUNTS WILL BE LIGHT. SNOW SHOWERS WILL AGAIN BECOME
MORE NUMEROUS AFTER 15Z. VFR CONDITIONS PREVAIL WITH MVFR/IFR
CONDITIONS POSSIBLE IN THE VICINITY OF SNOW SHOWERS. MOUNTAINS
OBSCURED AT TIMES.
&&
.PREV DISCUSSION...ISSUED 232 PM MST SUN JAN 31 2016
TONIGHT THROUGH TUESDAY...A LIGHT NORTHWESTERLY FLOW ALOFT HAS
DEVELOPED OVER THE REGION TODAY. THE FLOW ALOFT...COMBINED WITH
COLD AIR ALOFT AND A WEAK UPPER LEVEL DISTURBANCE MOVING THROUGH
THE REGION...AS ALLOWED FOR SCATTERED SNOW SHOWERS/SNOW GRAINS TO
DEVELOP OVER THE REGION. MOST OF THE SNOW SHOWERS ARE LIGHT IN
INTENSITY...BUT A FEW HEAVIER SNOW SHOWERS WITH VISIBILITIES BELOW
ONE MILE ARE POSSIBLE AT TIMES. THE SNOW SHOWERS WILL CONTINUE
INTO THE OVERNIGHT HOURS AND THROUGH THE DAY ON MONDAY. NEW SNOW
ACCUMULATIONS TONIGHT WILL GENERALLY BE LESS THAN 1/2 INCH AT
LOWER ELEVATIONS AND AROUND 1 INCH IN THE MOUNTAINS. THE SAME
AMOUNT OF SNOW ACCUMULATIONS ARE POSSIBLE ON
MONDAY...HOWEVER...SOME MELTING WILL OCCUR DURING THE LATE
MORNING/AFTERNOON HOURS ON MONDAY REDUCING THE SNOWFALL
ACCUMULATION A BIT. THE MAIN IMPACT FROM THE SNOWFALL WILL BE
QUICKLY REDUCED VISIBILITIES...AND THAT BRIDGES CAN ICE OVER
QUICKER THAN ROADWAY SURFACES. ADDITIONALLY...SOME WET ROADWAYS
WILL GRADUALLY FREEZE OVER THIS EVENING AFTER SUNSET. FOR
TUESDAY...THE NORTHERLY FLOW ALOFT CONTINUES...WITH A FEW
SCATTERED SNOW SHOWERS AS WELL. HOWEVER...AT THIS TIME...MOST OF
THE SNOW SHOWERS ON TUESDAY WILL MAINLY AFFECT MOUNTAIN AREAS.
OVERALL...TEMPERATURES WILL CONTINUE TO BE A FEW DEGREES BELOW
NORMAL THROUGH THE ENTIRE PERIOD BUT NOT QUITE AS COLD AS
PREVIOUSLY THOUGHT. BRUSDA
TUESDAY NIGHT THROUGH SUNDAY...THIS PERIOD BEGINS WITH WEAK
SHORTWAVE TROF STEADILY EXITING INTO SOUTH CENTRAL MT AND NORTHERN
WY. A FEW RESIDUAL SNOW SHOWERS WILL MOVE ACROSS PARTS OF SOUTHWEST
MT AND THE ROCKY MTN FRONT AS THE TROF PASSES THROUGH, BUT ONLY
MINIMAL SNOWFALL AMOUNTS ARE EXPECTED. LATEST ECMWF AND GFS MODEL
SOLUTIONS ARE BACK IN GOOD AGREEMENT ON ARRIVAL OF HIGH PRESSURE
RIDGING FROM WED AFTN THROUGH MIDDAY THURS AND NEXT PACIFIC
SHORTWAVE MOVING THROUGH OUR REGION THURS AFTN AND FRI. THE RIDGE
WILL PROVIDE A SHORT BREAK FROM THE COOL NORTHWEST FLOW ALOFT
EARLIER IN THE WEEK AS WINDS SHIFT MORE WESTERLY. HOWEVER, MODELS
CONTINUE EARLIER TREND OF LIMITING ANY DECENT WARM UP FROM THIS
SHIFT, AS NOTED IN 1000-500 MB THICKNESS VALUES THAT INCREASE BY
AROUND 100-120 METERS (SIGNALING WARM AIR ADVECTION) BY THURS
MORNING BUT ONLY TOP OUT AT ABOUT 5360 METERS (THE VALUE OFTEN
MARKING TEMPS NEAR FREEZING AND RAIN VS SNOW PRODUCTION). MUCH OF
THE REGION WILL ONLY MAKE IT INTO THE UPPER 20S TO MID 30S ON
THURS/FRI, BUT A STRONGER RIDGE WITH SLIGHTLY BETTER ADVECTION
(THICKNESS VALUES UP TO 5430 METERS) WILL FOLLOW FRIDAY`S WEATHER
SYSTEM, PUSHING TEMPS INTO THE MID 30S TO LOW 40S FOR THE WEEKEND.
THE BEST CHANCE FOR PRECIPITATION EAST OF THE CONTINENTAL DIVIDE
WILL BE THURS NIGHT THROUGH FRI MORNING, WITH MUCH OF OUR AREA
SEEING INTERMITTENT PERIODS OF LIGHT SNOW. WITH ONLY MARGINAL
SHORTWAVE DYNAMICS AND LIQUID PRECIP VALUES OF A TENTH OF AN INCH OR
LESS, SNOWFALL ACCUMULATIONS AT LOWER ELEVATIONS SHOULD LIKELY BE
AROUND A TRACE TO A HALF-INCH BEFORE THE SNOW TAPERS OFF FRI
AFTN/EVE.
WARANAUSKAS
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 19 30 16 31 / 30 30 10 20
CTB 15 29 14 30 / 30 20 10 10
HLN 14 25 11 26 / 20 30 20 20
BZN 4 22 3 21 / 20 30 20 20
WEY 0 20 -2 18 / 20 10 10 10
DLN 4 19 2 18 / 20 20 20 20
HVR 19 30 16 32 / 30 30 10 10
LWT 17 29 13 29 / 30 40 20 20
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
WEATHER.GOV/GREATFALLS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1227 AM CST MON FEB 1 2016
.UPDATE...
ISSUED AT 1221 AM CST MON FEB 1 2016
ONLY MINOR ADJUSTMENTS WERE MADE TO PRECIP CHANCES AND
TEMPERATURES OVERNIGHT.
VERY LIGHT RADAR RETURNS CONTINUED ACROSS PORTIONS OF WESTERN
NORTH DAKOTA. THEREFORE...LEFT A SLIGHT CHANCE OF SNOW IN BUT
REDUCED THE EASTWARD EXTENT.
TEMPERATURES UNDER A STRATUS DECK ACROSS NORTHERN NORTH DAKOTA
WILL REMAIN WARMER TONIGHT THAN THE PREVIOUS FORECAST INDICATED.
THEREFORE...INCREASED LOW TEMPERATURES A FEW DEGREES.
UPDATE ISSUED AT 930 PM CST SUN JAN 31 2016
FOR LATE EVENING UPDATE HAVE ADDED SOME LOW POPS OVER PORTIONS OF
THE WEST AND CENTRAL AS A WEAK WAVE MOVING THROUGH THE REGION IS
PRODUCING SOME LIGHT ECHOS ON AREA RADARS. STILL HAVE NOT HAD ANY
OBSERVATIONS REPORTING SNOW YET...AND WITH THE ECHOS ON THE WEAK
SIDE WILL KEEP POPS ON THE LOW END.
UPDATE ISSUED AT 612 PM CST SUN JAN 31 2016
FOR EARLY EVENING UPDATE HAVE INCREASED CLOUD COVER A BIT OVER
CENTRAL NORTH DAKOTA IN LINE WITH CURRENT SATELLITE. CONSIDERED
FOG FOR LATER TONIGHT OVER THE NORTH CENTRAL AS LATEST HRRR IS
SUGGESTING SOME DEVELOPING FROM THE NORTH...BUT AT THIS TIME SEE
MINIMAL VISIBILITY RESTRICTIONS NORTH OF THE BORDER. WILL KEEP AN
EYE ON THIS AND MAY END UP ADDING IN LATER UPDATES.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 232 PM CST SUN JAN 31 2016
MAIN FORECAST ISSUE IN THE SHORT TERM WILL BE TEMPERATURES AND
CLOUDS. PRETTY QUIET WEATHER WISE WITH A CONTINUED GRADUAL COOLING
TREND.
CURRENTLY...PARTLY SUNNY SKIES ACROSS WESTERN AND CENTRAL NORTH
DAKOTA. NORTHWEST WINDS GENERALLY 10 TO 15 MPH...BUT GUSTING TO
AROUND 25 MPH OVER THE SOUTHWEST. TEMPERATURES WERE MAINLY IN THE
30S AND LOWER 40S.
LATE THIS AFTERNOON...MAYBE A DEGREE OR TWO RISE POSSIBLE YET THIS
AFTERNOON OVER THE SOUTHERN JAMES RIVER VALLEY. ELSEWHERE
TEMPERATURES HAVE REACHED THEIR HIGHS AND WILL BEGIN TO DROP.
TONIGHT AND MONDAY...MESOSCALE MODELS CONTINUE TO ADVERTISE LOW
CEILINGS EXTENDING FROM NORTHWEST INTO SOUTH CENTRAL NORTH DAKOTA
AND THIS IS YET TO MATERIALIZE. THERE IS A BAND OF MID LEVEL
CLOUDS AND EVEN SOME AREAS OF FOG OVER NORTHEAST NORTH
DAKOTA...AND HAS BEEN TRYING TO CREEP INTO THE TURTLE MOUNTAINS
AND NORTHERN JAMES RIVER VALLEY FROM THE EAST. OTHERWISE THERE IS
MORE SUN THAN CLOUDS ACROSS THE CWA THIS AFTERNOON AND THINK
MESOSCALE AND DETERMINISTIC GLOBAL MODELS ARE OVERDOING THE LOW
CLOUDS. WITH THIS SAID...WE ARE AT THE BEGINNING OF A LONG PERIOD
OF COLD ADVECTION AND EXPECT LOWER STRATUS TO MAKE A VISIT. BUT IF
YOU LOOK UPSTREAM YOU DONT SEE MUCH IN THE WAY OF STRATUS UNTIL
YOU GET NORTH OF REGINA SASKATCHEWAN...AND YOU DONT SEE REAL COLD
TEMPERATURES UNTIL WELL INTO CENTRAL SASKATCHEWAN. THEREFORE OUR
FORECAST FOR TONIGHT AND SUNDAY IS ON THE WARMER SIDE OF GUIDANCE
AND WE DONT INTRODUCE THE STRATUS UNTIL LATE TONIGHT INTO MONDAY
MORNING. WE DID INTRODUCE A MENTION OF PATCHY FOG OVER THE
SOUTHERN JAMES RIVER VALLEY LATE TONIGHT INTO MONDAY MORNING AS
THE AREA OF FOG/STRATUS OVER NORTHEAST NORTH DAKOTA TODAY SAGS
SOUTH. MESOSCALE MODELS AND MOS GUIDANCE ARE BOTH INDICATING FOG
IN/NEAR THE SOUTHERN JRV.
COULD SEE A PASSING SNOW SHOWER OR TWO BUT EVEN THE MESOSCALE
MODELS ARE PRETTY MEAGER WITH ANY REFLECTIVITIES TONIGHT INTO
MONDAY MORNING. SO WILL KEEP THE FORECAST DRY FOR NOW.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 232 PM CST SUN JAN 31 2016
THE OVERALL TREND FOR COLDER TEMPERATURES/A RETURN TO NORMAL OR
SLIGHTLY ABOVE NORMAL HIGHS REMAINS ON TRACK. ALSO...SEVERAL ALBERTA
CLIPPER TYPE SYSTEMS WILL SWEEP THROUGH...WITH PERHAPS THE STRONGEST
ONE COMING AT THE END OF THE LONG TERM PERIOD...SUNDAY.
MONDAY NIGHT THROUGH TUESDAY...A LULL IN ANY SIGNIFICANT WEATHER
ACROSS NORTH DAKOTA AS A POTENT WINTER STORM PASSES WELL SOUTH OF
NORTH DAKOTA...IMPACTING THE CENTRAL PLAINS AND INTO THE GREAT LAKES
AND OHIO VALLEY TUESDAY INTO WEDNESDAY. HIGHS WILL COOL TO AVERAGE
FOR THIS TIME OF YEAR UNDER MOSTLY TO PARTLY CLOUDY CONDITIONS.
TUESDAY NIGHT THROUGH SUNDAY...IT WILL BE DURING THIS TIMEFRAME WE
EXPERIENCE FOUR ALBERTA TYPE CLIPPER SYSTEMS/COLD FRONTS SWEEPING
THROUGH. TIMING OF THESE CLIPPER SYSTEMS IS SLATED FOR TUESDAY
NIGHT/WEDNESDAY...THURSDAY NIGHT...FRIDAY NIGHT...AND THE STRONGEST
ONE AS MENTIONED ABOVE SUNDAY/SUNDAY NIGHT.
FOR THE CLIPPER SYSTEM TUESDAY NIGHT/WEDNESDAY...SPOTTY SNOWSHOWERS
WITH UP TO A COUPLE TENTHS OF SNOWFALL ACCUMULATION POSSIBLE FAR
NORTH INTO THE TURTLE MOUNTAINS. HOWEVER WITH NOT MUCH SNOWFALL NOR
WIND ASSOCIATED WITH THIS CLIPPER...EXPECT MINIMAL IMPACTS.
WEDNESDAY NIGHT THROUGH FRIDAY NIGHT...IMPACTS MINIMAL. FOR THURSDAY
NIGHTS CLIPPER...A DUSTING UP TO A COUPLE TENTHS IN THE SOUTHWEST
AND PORTIONS OF SOUTH CENTRAL PER GFS...HOWEVER THE ECMWF PAINTS A
FEW SNOW SHOWERS IN THE TURTLE MOUNTAINS BUT KEEPS THE SOUTHWEST AND
SOUTH CENTRAL DRY. AGAIN A LACK OF ANY SIGNIFICANT WIND OR SNOW
RESULTS IN LITTLE TO NO TRAVEL IMPACT. WINDS BECOME SLIGHTLY BREEZY
FRIDAY AND FRIDAY NIGHT WITH THE NEXT CLIPPER AS BOUNDARY LAYER
WINDS INCREASE TO 20KT-25KT...BUT SNOWFALL POTENTIAL REMAINS LIMITED
TO THE TURTLE MOUNTAINS WITH UP TO A COUPLE TENTHS AT BEST.
SATURDAY THROUGH SUNDAY...BOTH THE GFS AND ECMWF SHOW A MUCH
STRONGER CLIPPER PUSHING THROUGH WITH BOUNDARY LAYER WINDS OF 40KT.
BUFKIT SOUNDINGS SHOW 40-45KT IN THE MIXED LAYER AND AROUND 50KT AT
THE TOP OF THE MIXED LAYER SUNDAY FOR WILLISTON/MINOT/DICKINSON AND
BISMARCK. LIGHT SNOW IS FORECAST TO COINCIDE WITH THE STRONG
WINDS...SO THIS WILL NEED TO BE WATCHED IN THE COMING DAYS. BECAUSE
OF THE CLIPPERS FAST SPEED THROUGH NORTH DAKOTA...SNOWFALL TOTALS
ARE NOT OVERLY IMPRESSIVE/PERHAPS AN INCH OR TWO...BUT WHATEVER DOES
FALL AT THE TIME OF THE STRONG WINDS MAY RESULT IN VISIBILITY
ISSUES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1221 AM CST MON FEB 1 2016
VFR CONDITIONS SHOULD TRANSITION TO MVFR AT ALL SITES BY THIS
MORNING. THERE IS SOME UNCERTAINTY AS TO EXACTLY HOW LOW THE CIGS
WILL BE. SOME LOCATIONS COULD FLIRT WITH IFR CONDITIONS WHILE
OTHERS REMAIN ON THE VFR/MVFR FRINGE. AT THIS TIME IT APPEARS
KJMS/KMOT/KISN STAND THE BEST CHANCE AT SEEING LOWER CIGS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...TWH
LONG TERM...KS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1137 PM CST SUN JAN 31 2016
.UPDATE...
ISSUED AT 1133 PM CST SUN JAN 31 2016
NO UPDATE NECESSARY.
UPDATE ISSUED AT 927 PM CST SUN JAN 31 2016
ADJUSTED SKY COVER THROUGH THE REMAINDER OF THE EVENING OTHERWISE
CURRENT FORECAST ON TRACK.
UPDATE ISSUED AT 638 PM CST SUN JAN 31 2016
NO SIGNIFICANT CHANGES TO CURRENT FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 253 PM CST SUN JAN 31 2016
THE MAIN ISSUE FOR THE PERIOD WILL BE ANY PATCHY FOG AND LIGHT
SNOW CHANCES OVERNIGHT.
WV LOOP SHOWS A FAIRLY DECENT SHORTWAVE TROUGH MOVING THROUGH
SOUTHERN MANITOBA. SOME SNOW HAS DEVELOPED NEAR THE
SHORTWAVE...BUT VISIBILITY READINGS AT WINNIPEG AND BRANDON HAVE
NOT GONE LOWER THAN 3SM...MORE OFTEN 6 MILES OR ABOVE. MODELS
CONTINUE TO BRING SOME LIGHT QPF INTO OUR NORTHERN COUNTIES THIS
EVENING...EVENTUALLY TRANSITIONING TO THE LAKE OF THE WOODS AREA
TOWARDS MORNING. WILL KEEP SOME 20ISH POPS GOING...BUT DO NOT
THINK WE WILL GET MORE THAN A DUSTING OF SNOWFALL.
THE SHORTWAVE HAS STARTED TO SHOVE SOME STRATUS DOWN INTO OUR
NORTH CENTRAL CWA. SOME LOWERED VISIBILITIES CONTINUE ALONG THE
LEADING EDGE OF THE STRATUS. THIS IS IN ADDITION TO PATCHY FOG
THAT HAS BEEN PERSISTENT IN HANGING ON OVER THE EASTERN COUNTIES.
THE SHORT RANGE MODELS ARE ALL MORE AGGRESSIVE ON BRINGING GOOD
925 TO 850MB MOISTURE DOWN INTO THE CWA TONIGHT. HRRR AND TO SOME
EXTENT THE RAP HAVE FOG FORMING ALONG AND AHEAD OF THE STRATUS.
THINK THAT SOME PATCHY FOG WILL BE POSSIBLE AGAIN THIS EVENING
ACROSS THE NORTHWESTERN TO CENTRAL CWA...WITH THE BEST FOG CHANCES
EVENTUALLY MOVING TO OVER THE SOUTHERN CWA AS THE STRATUS PUSHES
IN FROM THE NORTH. AT THIS POINT THINK THAT THE MAIN FOG WILL BE
ALONG THE FRONT EDGE OF THE CLOUD DECK...BUT WILL HAVE TO KEEP AN
EYE ON THINGS AS THE EVENING PROGRESSES. WITH CLOUDS AND SOME
LIGHT NORTHWEST WINDS TEMPERATURES WILL STAY IN THE UPPER TEENS TO
LOW 20S OVERNIGHT.
MONDAY AND INTO MONDAY NIGHT...THE MAIN ACTIVITY WILL BE WELL TO
OUR SOUTH WITH THE NORTHERN PLAINS UNDER WEAK SFC HIGH PRESSURE
AND COLD AIR ADVECTION. TEMPS WILL CONTINUE TO SEE A SLOW COOLING
TREND...WITH HIGHS IN THE 20S AND LOWS IN THE SINGLE DIGITS AND
TEENS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 253 PM CST SUN JAN 31 2016
TUESDAY AND WEDNESDAY...THE COOLING TREND CONTINUES AS A BROAD
UPPER TROUGH SETS UP FROM ONTARIO DOWN INTO THE SOUTHERN PLAINS.
SFC HIGH PRESSURE AND WEAK COLD AIR ADVECTION WILL CONTINUE TO
DROP TEMPS THROUGH TUESDAY AND TUESDAY NIGHT...ALTHOUGH SOME OF
THE MODELS ARE INDICATING SOME WARM AIR ADVECTION FOR
WEDNESDAY...SO SLOWED THE COOLING TREND. SOME LIGHT PRECIP IS
KICKED UP BY THE WARM AIR ADVECTION...SO INCLUDED SOME VERY LOW
POPS MAINLY IN THE NORTH FOR MID WEEK...AGAIN NOT EXPECTING MUCH
IF ANY ACCUMULATION.
WEDNESDAY NIGHT-SUNDAY...12Z GUIDANCE IS IN GOOD AGREEMENT
INDICATING A FAIRLY PROGRESSIVE LONGWAVE PATTERN THROUGH NEXT
WEEKEND...WITH PREDOMINANTLY NORTHWESTERLY FLOW ALOFT OVER THE
NORTHERN PLAINS. THIS PATTERN DOES NOT FAVOR SIGNIFICANT PRECIP
EVENTS. GLOBAL MODELS DO INDICATE A FEW PROGRESSIVE UPPER SHORTWAVE
TROUGHS LATE IN THE WEEK...WHICH COULD BRING A BIT OF LIGHT
SNOW...SO DO HAVE LOW POPS MENTIONED WED NIGHT AND FRI/FRI NIGHT.
12Z GFS/ECMWF INDICATE A STRONGER PACIFIC SHORTWAVE TROUGH ENTERING
THE PLAINS LATE NEXT WEEKEND...SO ALSO HAVE LOW POPS DURING THAT
TIME.
RUN-TO-RUN MODEL CONSISTENCY HAS BEEN POOR WITH DAY TO DAY TEMP
TRENDS LATELY IN THE EXTENDED. THE COLDEST AIR MASS IS GENERALLY
EXPECTED TO BE ACROSS CENTRAL AND EASTERN CANADA...AND TO WHAT
DEGREE WE TAP THAT COLDER AIR AT TIMES WILL DEPEND ON THE
AMPLIFICATION OF THE UPPER FLOW AIDED BY EMBEDDED SHORTWAVE TROUGHS.
LATEST DETERMINISTIC GFS/ECMWF VARY ON THE FLOW ORIENTATION AND TEMP
FIELDS SIGNIFICANTLY FOR LATE WEEK...AND WILL THEREFOR CONTINUE
TO MAINTAIN MODEL CONSENUS TEMPS FOR NOW...REASONABLY CLOSE TO
SEASONAL NORMS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1133 PM CST SUN JAN 31 2016
MVFR LOCALLY IFR CIGS ROUGHLY ACROSS THE NE HALF OF THE FA. FAR
AND DVL ON THE WESTERN EDGE. SO FAR FOG HAS BEEN LIMITED TO THE
FAR TAF AND HAS BEEN UP AND DOWN. WITH BEST POTENTIAL FOR LACK OF
CIGS MAINTAINED FOG MENTION IN FARGO. ELSEWHERE CIGS SHOULD LIMIT
FOG. THESE CIGS SHOULD PERSIST FOR A GOOD PART OF THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...JR
LONG TERM...JR/MAKOWSKI
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
304 AM EST MON FEB 1 2016
.SYNOPSIS...
COLD FRONT PASSES TODAY BUT MILD AGAIN TUESDAY. STRONG SYSTEM MID
WEEK. A RETURN TO COLDER WEATHER FOLLOWS THAT SYSTEM TO END THE
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
IT LOOKS LIKE THE DECOUPLING ISSUES WHICH WERE CAUSING WIDELY
VARYING TEMPERATURES SUNDAY EVENING HAVE SORTED THEMSELVES OUT
WITH EROSION OF THE LOW LEVEL INVERSION. EKN JUMPED OVER 20
DEGREES IN ONE HOUR WITH AN INCREASE IN WIND. CANNOT RULE OUT VERY
SHELTERED VALLEY STAYING DECOUPLED FOR ANOTHER COUPLE HOURS...BUT
IN GENERAL A VERY MILD PRE-DAWN IS IN STORE WITH BREEZY SOUTHERLY
WINDS.
HAVE A PRE-FRONTAL BAND OF PRECIP ALONG THE OHIO RIVER AND MOVING
EAST AS OF AROUND 06Z...WITH THE COLD FRONT RUNNING FROM NE TO SW
ACROSS CENTRAL OHIO. THIS FRONT WILL MOVE THROUGH CWA TODAY...AND
HAVE LIKELY POPS WITH IT. PROGRESSION OF THE FRONT WILL SLOW TO A
CRAWL THIS EVENING ACROSS THE SOUTHERN MOUNTAINS AND COAL
FIELDS...BUT DOES LOOK TO PUSH ALL THE WAY THROUGH THE FORECAST
AREA BY AROUND MIDNIGHT...STALLING SOMEWHERE JUST SOUTH OF THE
CWA.
USING A MIX OF THE HRRR AND LAMP...HAVE NON-DIURNAL TEMPERATURE
TRACE FOR TODAY...WITH GRADUALLY FALLING TEMPS BEHIND THE COLD
FRONT. MAY GET A BRIEF UPWARD BOUNCE IN SE OHIO LATE THIS
AFTERNOON IF THE CLOUDS CAN BREAK UP ENOUGH FOR SOME SUN.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
A WARM FRONT PUSHES NORTHWARD THROUGH THE AREA ON TUESDAY WITH
SOUTHERLY WINDS INCREASING. DUE TO RECENT MOS PERFORMANCE IN
SOUTHERLY WINDS...SIDED WITH THE WARMER GFS MOS.
MODELS THEN SHOW SHOWERS AND A COLD FRONT TUESDAY NIGHT INTO
WEDNESDAY. SOUNDINGS AND MOS GUIDANCE INDICATE THAT THUNDERSTORMS
ARE A POSSIBILITY. OF CONCERN IS A STRONG LOW LEVEL JET THAT
OVERLAPS THE INITIAL PRECIPITATION BAND. WORKING AGAINST THE WINDS
GETTING TO THE GROUND HOWEVER...ARE MODEL SOUNDINGS THAT SHOW AN
INVERSION. WILL NEED TO CONTINUE TO MONITOR THIS SITUATION
CLOSELY.
GFS AND ECMWF ARE THEN SHOWING 850 MB TEMPERATURES GETTING COLD
ENOUGH TO OVERTURN THE LOWER LEVELS AND POSSIBLY PRODUCE SOME LIGHT
SNOW OR FLURRIES FOR WEDNESDAY NIGHT INTO THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
ANY RESIDUAL WRAP AROUND RAIN SHOWERS IN THE WAKE OF A COLD FRONT
AND LARGE LOW PRESSURE SYSTEM SPEEDING NEWD AWAY FROM THE
AREA...WILL QUIT OVER THE LOWLANDS AND SWITCH TO UPSLOPE SNOW
SHOWERS OVER THE MOUNTAINS WED EVENING...AND THEN QUIT OVER THE
MOUNTAINS BY THU MORNING...AS LOW LEVEL NW FLOW BECOMES LIGHT
ANTICYCLONIC AHEAD OF HIGH PRESSURE APPROACHING FROM THE W.
THE HIGH MOVES ACROSS THE AREA FOR DRY...SEASONABLY CHILLY
WEATHER THU-SAT. THU DOES NOT LOOK TO PROMISE TOO MUCH
SUNSHINE...THOUGH...GIVEN LINGERING LOW LEVEL MOISTURE YIELDING
STRATOCU...AND HIGH CLOUD ASSOCIATED WITH A WAVE MOVING UP ALONG
THE FRONT THROUGH THE CAROLINAS.
MODELS ARE IN BETTER AGREEMENT ON THE NEXT COLD FRONT CROSSING THE
AREA ON SUNDAY...WITH ANY RAIN SHOWERS AHEAD OF IT SAT NT GOING TO
SOME SNOW SHOWERS OVERNIGHT AS THE FRONT CROSSES...A FEW SNOW
SHOWERS LINGERING ON SUNDAY IN ITS WAKE. THAT SAID...THE FRONT
LOOKS BARELY DISCERNIBLE IN THE ECMWF DEPICTION...AND THE MASS
FIELDS AS A WHOLE DIVERGE BY THEN. THIS LEADS TO UNCERTAINTY AS TO
THE TIMING OF THE NEXT SYSTEM APPROACHING AS EARLY AS THE END OF
DAY 7N NT...
WITH MODEL AGREEMENT THROUGH DAY 6...WPC GUIDANCE AND A BLEND OF
MODEL GUIDANCE WAS EMPLOYED FOR TEMPERATURES...NOT QUITE AS COLD
IN THE WAKE OF THE MID WEEK SYSTEM. LEANED MORE TOWARD THE COLDER GFS
DAY 7.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS IN PLACE EARLY MONDAY MORNING...BUT AS A COLD FRONT
APPROACHES AND SLIDES THROUGH...EXPECT MVFR CEILINGS AND
VISIBILITIES IN SHOWERS. ALSO HAVE A GOOD DOSE OF IFR IN THE
MOUNTAINS INTO THIS AFTERNOON. THIS DOES INCLUDE BKW. CLOUDS WILL
TRY TO BREAK UP LATE IN THE TAF PERIOD...BUT THIS SHOULD LEAD TO
DENSE FOG ACROSS AT LEAST THE EASTERN HALF OF CWA...ALTHOUGH IT
WILL LIKELY HOLD OFF UNTIL AFTER THE CURRENT TAF PERIOD.
CURRENTLY HAVE RATHER GUSTY SOUTHERN WINDS...THESE MAY DECREASE
SOME THROUGH THE EARLY MORNING. WINDS WILL THEN SHIFT TO WESTERLY
THEN NORTHERLY AS THE COLD FRONT PROGRESSES ACROSS THE FORECAST
AREA.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF FRONT AND SUBSEQUENT MVFR
CONDITIONS MAY VARY A BIT.
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 MON 02/01/16
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 H M L M M M L M M
HTS CONSISTENCY H H H M M L M M M M M M
BKW CONSISTENCY H H H H M M L L L L L L
EKN CONSISTENCY H H H H M M M M M M M M
PKB CONSISTENCY H H H M M M M H H H H H
CKB CONSISTENCY H H H H H M M M M M M M
AFTER 06Z TUESDAY...
IFR POSSIBLE IN FOG TUESDAY MORNING. IFR POSSIBLE IN SHOWERS TUESDAY
NIGHT INTO WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY/MZ
NEAR TERM...MZ
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS MEDFORD OR
846 PM PST SUN JAN 31 2016
.DISCUSSION...LIGHT SHOWERS ARE MOVING INTO THE COOS COUNTY COAST
THIS EVENING WITH RAIN SPREADING INTO THE ROSEBURG AREA. OF THE
TWO SHORT TERM MODELS..THE RAP IS DOING BETTER THAN THE HRRR WHICH
SHOWS NO PRECIPITATION BEYOND THE IMMEDIATE COAST. WITH THE RAP AS
THE REFERENCE PRECIPITATION IS EXPECTED TO SPREAD SOUTH INTO
JACKSON COUNTY AROUND MIDNIGHT AND BY THAT TIME THE SNOW LEVEL
SHOULD BE VERY CLOSE TO THE VALLEY FLOOR IN MEDFORD. UP TO AN INCH
OF SNOW IS EXPECTED OVER THE SEXTON PASS AROUND MIDNIGHT. THE SNOW
SHOWERS SHOULD MOVE INTO THE SISKIYOU PASS AROUND 2-3 AM AND
CONTINUE OVER THE SISKIYOU PASS UNTIL AROUND 6 AM. ABOUT AN INCH
OF NEW SNOW IS EXPECTED THERE OVERNIGHT. NEITHER THE HRRR NOR THE
RAP SHOWS PRECIPITATION CROSSING VERY FAR BEYOND THE CASCADES.
WE HAVE UPDATED THE GRIDS TO PARE DOWN POPS THIS EVENING OVER
MOST AREA EXCEPT COOS AND DOUGLAS COUNTIES.
A FROST ADVISORY CONTINUE FOR THE COASTAL COUNTIES. THIS HOWEVER
HINGES ON CLEARING LATER TONIGHT WHICH COULD SEE LOWS DROPPING
INTO THE LOWER TO MID 30S. /FB
&&
.AVIATION...FOR THE 01/00Z TAF CYCLE...CONDITIONS REMAIN VFR AREA
WIDE THIS EVENING, BUT A WEAK SYSTEM WILL BRING SHOWERS AND
WIDESPREAD MVFR CIGS TO THE WEST SIDE OVERNIGHT. SHOWERS WILL BE
RAIN AT KOTH AND KRBG, BUT THEY MAY BE MIXED WITH SNOW AT KMFR,
ESPECIALLY LATE TONIGHT. SIMILAR CONDITIONS ARE EXPECTED EAST OF THE
CASCADES, HOWEVER, SHOWERS WILL BE LESS LIKELY AND MAINLY IN THE
FORM OF SNOW. IFR VIS/CIGS IN FOG/LOW CLOUD ARE POSSIBLE BEHIND THE
SYSTEM TOMORROW ON THE WEST SIDE, DEPENDING ON HOW QUICKLY SKIES
CLEAR. OTHERWISE, CONDITIONS WILL BE VFR TOMORROW. -WRIGHT
&&
.MARINE...UPDATED 130 PM PST SUN 31 JAN 2016...NORTH WINDS WILL PEAK
AT TO 20-25 KT BEYOND 10 NM FROM SHORE WITH LIGHTER WINDS OVER THE
INNER WATERS AND AROUND 10-15 KT WITHIN A FEW MILES OF SHORE.
HOWEVER, THE COMBINATION OF WEST SWELL AND WIND WAVE WILL KEEP STEEP
SEAS IN PLACE OVER ALL WATERS THROUGH THIS EVENING. ALL OF THIS
DIMINISHES LATER TONIGHT AS WINDS EASE, AND MONDAY SHOULD BE FAIRLY
QUIET WITH RELATIVELY LIGHT WINDS AND LOW SEAS. THERE MAY BE A BRIEF
PERIOD OF MODERATE WINDS AND STEEP SEAS AGAIN TUESDAY, WHICH WE WILL
ADDRESS AFTER THE CURRENT SMALL CRAFT ADVISORY ENDS. A MUCH STRONGER
FRONT IS EXPECTED WEDNESDAY WITH POSSIBLE SOUTH GALES AND VERY STEEP
COMBINED SEAS. IN FACT, LATEST GUIDANCE ALL AGREE ON THIS FRONT, SO
THE ONLY REMAINING ISSUE IS THE TIMING OF THE STRONGEST WINDS, NOT
THEIR OCCURRENCE. GALE AND HAZARDOUS SEAS WATCHES HAVE BEEN ISSUED
FOR WEDNESDAY AND WEDNESDAY EVENING. THIS FRONT WILL ALSO LIKELY BE
FOLLOWED BY ANOTHER HEAVY WEST SWELL. -WRIGHT
&&
.PREV DISCUSSION... /ISSUED 220 PM PST SUN JAN 31 2016/
DISCUSSION...31/12Z NAM/GFS IN.
THE NORTHERN HEMISPHERIC CHART SHOWS A 5 WAVE PATTERN AROUND THE
GLOBE...WHICH IS GENERALLY A PROGRESSIVE PATTERN. THERE IS A
MODERATE AMOUNT OF LONGITUDINAL FLOW AND A MODERATE JET STREAM
NOW CENTERED OVER CENTRAL CALIFORNIA. SOUTHERN OREGON AND EXTREME
NORTHERN CALIFORNIA ARE ON THE COLD SIDE OF THE JET WITH COLD
TEMPERATURES AND LOW SNOW LEVELS.
LOOKING CLOSER IN...A WEAK LONG WAVE TROUGH OFFSHORE WILL EJECT A
FEW MORE SHORT WAVES OUR WAY WITH MOST OF THE ENERGY STREAMING
INTO CENTRAL CALIFORNIA. IT WILL BE SHOWERY TODAY WITH THE BULK OF
THE PRECIPITATION FALLING ALONG THE COAST...IT WILL BE VERY LIGHT
ELSEWHERE. SNOW LEVELS WILL BE LOW...IN THE 1500-2500 FOOT RANGE.
THERE IS ALSO THE POSSIBILITY OF ISOLATED THUNDERSTORMS ALONG THE
COAST AND OFFSHORE.
THE LONG WAVE TROUGH WILL MOVE INLAND TODAY AND A LONG WAVE RIDGE
WILL BUILD INTO THE AREA. THE LAST OF THE SHORT WAVES MOVING DOWN
THE BACK SIDE OF THE TROUGH WILL MOVE OFF TO THE EAST BY MONDAY
AFTERNOON. SCATTERED LIGHT SHOWERS...PEAKING WITH WHAT AFTERNOON
HEATING THERE IS...WILL PERSIST INTO THIS EVENING. SHOWERS WILL
DIMINISH TONIGHT...BUT WON`T CUT OFF COMPLETELY...THERE WILL BE
ANOTHER ROUND MONDAY.
A STRONG SHORT WAVE WILL MOVE OVER THE TOP OF THE RIDGE AND
ONSHORE LATE MONDAY NIGHT INTO TUESDAY MORNING. THE WAVE WILL
WEAKEN AS IT MOVES IN AND WON`T AMOUNT TO MUCH BY THE TIME IT GETS
HERE. IT WILL SLOW DOWN AND WEAKEN AS IT MOVES THROUGH THE
AREA...MOVING OUT TO THE EAST TUESDAY NIGHT. THIS WILL BRING A
ROUND OF ENHANCED SHOWER ACTIVITY LATE MONDAY NIGHT THROUGH
TUESDAY EVENING...ONCE AGAIN MOSTLY NEAR THE COAST. IT STILL WON`T
AMOUNT TO MUCH THOUGH...FLOODING IS NOT A CONCERN HERE. AN
OFFSHORE RIDGE WILL MOVE IN TUESDAY NIGHT INTO WEDNESDAY.
THE PATTERN WILL REMAIN PROGRESSIVE...AND THE RIDGE AXIS WILL
BREAK TO THE EAST OF THE CWA WEDNESDAY. THE NEXT LONG WAVE TROUGH
WILL MOVE IN RIGHT BEHIND IT...MOVING ONSHORE WEDNESDAY NIGHT. IT
WILL PUSH A COLD FRONT ONSHORE WEDNESDAY AFTERNOON. THE GFS AND EC
SOLUTIONS DIFFER SIGNIFICANTLY ON THE TRAJECTORY OF THIS SYSTEM.
IF THE GFS VERIFIES...THIS WILL BRING A ROUND OF HEAVIER AND
WIDESPREAD PRECIPITATION TO THE AREA. IT WILL BE A SIGNIFICANT
SYSTEM...BUT ONCE AGAIN NO FLOODING IS EXPECTED. IF THE EC
VERIFIES WITH A MORE NORTHERLY TRACK...THE BULK OF THE
ENERGY...AND PRECIPITATION...WILL GO NORTH OF THE CWA WITH
LIGHTER PRECIPITATION DOWN HERE.
LONG TERM...THURSDAY THROUGH SUNDAY...THE 12Z ECMWF AND GFS
MODELS HAVE TRENDED TOWARD EACH OTHER AND ARE IN MUCH BETTER
AGREEMENT REGARDING THE THURSDAY FORECAST THAN THEY WERE 24 HOURS
AGO. HOWEVER...THERE ARE STILL SOME DIFFERENCES. THE ECMWF HAS A
SLIGHTLY WETTER AND COLDER SOLUTION BUT THE GENERAL PATTERN IS
THAT A WEAK SHORTWAVE TROUGH IN A WEST TO NORTHWEST FLOW ALOFT
WILL TRACK ACROSS THE NORTHERN PORTION OF THE PACIFIC NORTHWEST.
THIS WILL RESULT IN A SLIGHT CHANCE TO CHANCE OF LIGHT
PRECIPITATION WITH A SNOW LEVEL AROUND 4000 TO 4500 FEET. THE
PROBABILITY WILL BE HIGHEST IN COOS AND DOUGLAS COUNTIES NORTHWARD
WITH AMOUNTS LIKELY TO BE LESS THAN A TENTH OF AN INCH.
THE PROBABILITY OF PRECIPITATION WAS REDUCED ON THURSDAY NIGHT WITH
A RIDGE EXPECTED TO BUILD OVER THE CALIFORNIA AND SOUTHERN OREGON
COAST. THE RIDGE LOOKS TO PERSIST INTO FRIDAY AND BE STRONG ENOUGH
TO BRIEFLY PUSH THE STORM TRACK NORTH OF OUR AREA. DW
MODELS HAVE COME INTO AGREEMENT THAT A TROUGH WILL APPROACH THE CWA
FRIDAY NIGHT. STRONG SOUTH WINDS IN THE MARINE WATERS WILL OCCUR
AHEAD OF THE ASSOCIATED COLD FRONT FRIDAY INTO SATURDAY.
PRECIPITATION IS EXPECTED ALONG THE COAST AS THE FRONT PASSES
OVER. IF THE FRONT MAINTAINS ITS STRENGTH AS IT MAKES LANDFALL,
INLAND AREAS MAY ALSO RECEIVE SOME PRECIPITATION LATE FRIDAY INTO
SATURDAY. THE MAIN IMPACTS ARE EXPECTED NORTH OF THE MEDFORD CWA,
THUS AFTER THE FRONTAL PASSAGE ALONG THE COAST, THE HIGHEST
CHANCES FOR PRECIPITATION ARE IN THE SOUTHERN OREGON CASCADES AND
EASTERN DOUGLAS COUNTY.
A RIDGE BUILDS IN LATE SATURDAY INTO SUNDAY KEEPING CONDITIONS DRY
EARLY IN THE WEEK. EXPECT WINDS TO TURN EASTERLY AS PRESSURE INLAND
RISES. TEMPERATURES WILL BE AT, OR A FEW DEGREES BELOW
NORMAL...EXCEPT FOR THE SOUTHERN COAST WHERE A SLIGHT BROOKINGS
EFFECT IS EXPECTED TO BRING TEMPERATURES TO SEVERAL DEGREES ABOVE
NORMAL. -MSC
AVIATION...FOR THE 31/18Z TAF CYCLE...CONDITIONS WILL BE MAINLY
VFR THIS AFTERNOON INTO THE EARLY EVENING WITH A SLIGHT CHANCE TO
CHANCE OF LIGHT SHOWERS AND SNOW SHOWERS...INCLUDING MVFR WITH
MOUNTAIN OBSCURATION IN THE VICINITY OF SHOWERS AND ALSO SMALL HAIL
AND A FEW LIGHTNING STRIKES ARE POSSIBLE ALONG AND NEAR THE COAST
INTO THE EVENING. THE COVERAGE OF SHOWERS AND MVFR CEILINGS AND
VISIBILITIES WILL INCREASE OVERNIGHT...ESPECIALLY WEST OF THE
CASCADES WITH A FREEZING LEVEL AROUND 2500 FT MSL. CONDITIONS WILL
GRADUALLY IMPROVE DURING MONDAY MORNING INTO MONDAY AFTERNOON WITH
MVFR LIKELY TO PERSIST LONGEST AND BE ACCOMPANIED BY LOCAL VALLEY
IFR IN COOS AND DOUGLAS COUNTIES. -DW
MARINE...UPDATED 130 PM PST SUN 31 JAN 2016...NORTH WINDS WILL PEAK
AT TO 20-25 KT BEYOND 10 NM FROM SHORE WITH LIGHTER WINDS OVER THE
INNER WATERS AND AROUND 10-15 KT WITHIN A FEW MILES OF SHORE.
HOWEVER, THE COMBINATION OF WEST SWELL AND WIND WAVE WILL KEEP STEEP
SEAS IN PLACE OVER ALL WATERS THROUGH THIS EVENING. ALL OF THIS
DIMINISHES LATER TONIGHT AS WINDS EASE, AND MONDAY SHOULD BE FAIRLY
QUIET WITH RELATIVELY LIGHT WINDS AND LOW SEAS. THERE MAY BE A BRIEF
PERIOD OF MODERATE WINDS AND STEEP SEAS AGAIN TUESDAY, WHICH WE WILL
ADDRESS AFTER THE CURRENT SMALL CRAFT ADVISORY ENDS. A MUCH STRONGER
FRONT IS EXPECTED WEDNESDAY WITH POSSIBLE SOUTH GALES AND VERY STEEP
COMBINED SEAS. IN FACT, LATEST GUIDANCE ALL AGREE ON THIS FRONT, SO
THE ONLY REMAINING ISSUE IS THE TIMING OF THE STRONGEST WINDS, NOT
THEIR OCCURRENCE. GALE AND HAZARDOUS SEAS WATCHES HAVE BEEN ISSUED
FOR WEDNESDAY AND WEDNESDAY EVENING. THIS FRONT WILL ALSO LIKELY BE
FOLLOWED BY ANOTHER HEAVY WEST SWELL. -WRIGHT
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...FROST ADVISORY FROM 2 AM TO 8 AM PST MONDAY FOR ORZ021-022.
CA...NONE.
PACIFIC COASTAL WATERS...GALE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY EVENING FOR
PZZ350-356-370-376.
HAZARDOUS SEAS WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY
EVENING FOR PZZ350-356-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 PM PST THIS
EVENING FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PST MONDAY
FOR PZZ370-376.
$$
FJB/DW/TRW
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
204 AM EST MON FEB 1 2016
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS MORNING.
LOW PRESSURE WILL TRACK WEST OF PENNSYLVANIA DURING THE MIDDLE OF
THE WEEK...PUSHING A TRAILING COLD FRONT THROUGH THE AREA LATE
WEDNESDAY. HIGH PRESSURE WILL BUILD OVER THE REGION LATE NEXT
WEEK.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
CENTRAL PA IN THE WARM SECTOR SOUTH OF LOW OVR THE GRT LKS THIS
EVENING. AT 07Z...A NEARLY SOLID...20NM WIDE BAND OF SHOWERS
WAS LOCATED ALONG AND JUST AHEAD OF TRAILING COLD FRONT THAT
EXTENDED FROM NEAR CYYZ TO KCLE AND KCMH.
05Z HRRR SHOWS THIS RIBBON OF SHOWERS STAYING CONFINED TO MAINLY
THE NW MTNS THROUGH 09Z...BEFORE BECOMING MUCH MORE FRAGMENTED
NEAR THE I-99/RT 220 CORRIDOR AROUND 11Z...THEN DISSIPATING FOR
THE REST OF THE MORNING AND EARLY AFTERNOON AS THE COLD FRONT
TRACKS SE ACROSS THE CWA.
MADE JUST A FEW UPWARD MODIFICATIONS TO POPS AND TEMPS ACROSS THE
NW HALF OF THE CWA EARLY TODAY. OTHERWISE...THE CURRENT RUNNING
TEXT FORECAST AND NEAR TERM GRIDDED FIELDS LOOK IN DECENT SHAPE.
LATEST GEFS/SREF BOTH SUPPORT NEAR 100 PCT POPS ACROSS THE NW
MTNS...DUE IN PART TO OROGRAPHIC LIFT IN SW FLOW AND ALSO BECAUSE
THIS PART OF THE STATE WILL BE CLOSEST TO THE NOSE OF A STRONG
SWRLY LLJ...AND THE PARENT SHORTWAVE LIFTING ACROSS THE E GRT
LKS. DOWNSLOPING WSW FLOW AND WANING LG SCALE FORCING WILL CAUSE
BAND OF FRONTAL SHOWERS TO DIMINISH MARKEDLY AS THEY PUSH INTO THE
CENTRAL RIDGE AND VALLEY COUNTIES TOWARD DAWN.
06Z SFC ANALYSIS EXHIBITING THE NOW FAMILIAR PATTERN COLDEST
TEMPS ACROSS THE SCENT MTNS AND LOWER-MID SUSQ VALLEY...WHERE THE
DEEPER SNOW COVER AND LIGHT WIND HAVE ALLOWED READINGS TO FALL
INTO THE L-M 30S IN SOME LOCATIONS...WHILE A SW BREEZE IS HOLDING
READINGS NR 50F ACROSS THE ALLEGHENY PLATEAU. INCREASING CLOUD
COVER AND SW BREEZE SHOULD HOLD TEMPS UP OVERNIGHT ACROSS THE W
MTNS UNTIL ARRIVAL OF COLD FRONT LATE. OVER THE SE COUNTIES...
EXPECT READINGS TO SLOWLY RISE TO ARND 40F BY DAWN UPON ARRIVAL OF
CLOUDS.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
IT WILL START OFF CLOUDY TODAY WITH A CORRIDOR OF ISOLATED-SCT
/AND DIMINISHING/ SHOWERS WORKING FROM THE CENTRAL MTNS TOWARD
THE LOWER SUSQ VALLEY ALONG COLD FRONT. LATEST MDL DATA SUGGESTS A
FEW -SHRA COULD LINGER ACROSS THE SE COUNTIES INTO EARLY AFTN.
OTHERWISE...THE PM HOURS SHOULD BE DRY WITH GRADUALLY BRIGHTENING
SKIES...AS DRIER AIR AND HIGH PRESSURE BUILD INTO THE AREA.
HIGHS TODAY WILL AVERAGE IN THE 40S. WHILE SEVERAL DEG COOLER
THAN TODAY IN MOST LOCATIONS...MAX`S WILL STILL AVERAGE SOME 5-10
DEG WARMER THAN NORMAL FOR THE FIRST DAY OF FEBRUARY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
EXPANSIVE ZONAL FLOW PATTERN...COMBINING THE NORTHERN AND
SOUTHERN STREAMS OF THE MAIN JET...STRETCHES FROM COAST TO COAST
THIS WEEKEND. THE FLOW PATTERN IS FORECAST TO EVOLVE INTO A
BROAD...LONGWAVE TROF PATTERN IN THE SOUTHERN STREAM OVER THE
FRONT RANGE OF THE ROCKIES EARLY IN THE WEEK. THE TROF IS FORECAST
TO BE PROGRESSIVE...AIDED BY AND RE-PHASING WITH NRN STREAM
ENERGY...CROSSING THE PLAINS MIDWEEK AND REACHING THE OH/TN
VALLEYS TOWARD THE END OF THE WEEK.
MODEL GUIDANCE SHOWS THINGS DRYING OUT MONDAY NIGHT INTO
TUESDAY...WITH FOCUS SHIFTING TO STRONG STORM SYSTEM EXPECTED TO
TRACK FROM THE FOUR CORNERS THROUGH THE PLAINS AND GREAT LAKES
INTO EASTERN CANADA. CENTRAL PA WILL REMAIN ON THE WARM SIDE OF
THIS DYNAMIC SYSTEM WITH ABOVE NORMAL TEMPS EXPECTED THROUGH
WEDNESDAY...WHICH WILL DRAMATICALLY REDUCE THE CURRENT SNOWPACK
OVER SOUTHERN MTNS AND SUSQ VALLEY.
MODEL BLENDS CONTINUE TO SUPPORT A STRONG SIGNAL FOR PRECIP ON
WEDNESDAY AND MAINTAINED HIGH POPS FOR THIS PERIOD. THE GUIDANCE
APPEARS TO BE FOCUSING A MOD-HVY RAINFALL AXIS ALONG AND TO THE
EAST OF THE APPALACHIANS WHICH SEEMS TIED TO STRONG H85 MSTR FLUX
ANOMS CENTERED WITHIN 40-50KT SWLY PRE-FRONTAL LOW LEVEL JET. THE
FRONTAL BAND PCPN COULD BE CONVECTIVELY ENHANCED WITH WARM SECTOR
PROGGED TO SURGE WELL INTO NEW ENGLAND. FCST MAX TEMPS ARE
CURRENTLY IN THE 48-58F RANGE WHICH COULD BE SUPPORTIVE OF SOME
MARGINAL INSTABILITY.
ALL GUIDANCE POINTS TOWARD A DECENT SHOT OF COLD AIR BEHIND THE
MIDWEEK SYSTEM STARTING THURSDAY /WITH A QUICK SHOT FOR SOME LAKE
EFFECT SNOW SHOWERS/ FOLLOWED BY A REINFORCING SHOT OF COLDER AIR
NEXT WEEKEND.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
BAND OF RAIN ALONG COLD FRONT OVER THE NW AIRSPACE SHOULD WEAKEN
AS IT MOVES EAST THIS MORNING. EXPECT VFR TO HOLD FOR THE MOST
PART OVER CENTRAL AND EASTERN SITES. GFS-BASED GUIDANCE HAS BEEN
TOO PESSIMISTIC RECENTLY AND SEEMS OVERDONE WITH IFR VIS INVOF
MDT/LNS. POST FRONTAL CIGS SHOULD LOWER TO MVFR OR EVEN IFR FOR A
TIME TOWARD DAYBREAK. BEHIND FROPA SFC WINDS WILL BE SHIFTING FROM
200-240 TO 280-320 WITH 15-20KT GUSTS DIMINISHING. STRONG WSW LLJ
AHEAD OF COLD FRONT WILL KEEP LLWS MENTION UNTL 09-12Z BEFORE
WEAKENING. IMPROVING CONDITIONS FCST BY THIS EVE WITH RETURN TO
VFR AT ALL SITES.
OUTLOOK...
TUE...MAINLY VFR. RAIN...SUB-VFR CIGS AND LLWS DEVELOPING TUESDAY
NIGHT.
WED...MVFR/IFR. RAIN SHOWERS. LLWS. GUSTY WINDS 25+KT FROM
160-190 DEGREES SHIFTING TO 270-300 WED PM BEHIND THE COLD FRONT.
THU...MVFR CIGS/SCT -SHSN WEST. VFR CENTRAL-EAST. LIGHTER WINDS.
FRI...NO SIG WX.
&&
.HYDROLOGY...
LATEST MODEL ENSEMBLE RIVER FORECASTS /MMEFS/ FOR THE GEFS AND
NAEFS SUGGEST THE POTENTIAL FOR MINOR FLOODING ACROSS SOUTH-
CENTRAL AND SOUTHEAST PA WEDNESDAY INTO THURSDAY/FEBRUARY 3-4.
MARFC ALSO ISSUED A FLOOD OUTLOOK FOR THIS AREA. THE MAIN AREA OF
CONCERN AT THIS TIME IS ACROSS THE JUNIATA AND LOWER MAIN STEM
SUSQUEHANNA BASINS WHERE SNOWMELT RATES WILL BE INCREASING DUE TO
A PROLONGED PERIOD OF MILD/ABOVE NORMAL TEMPERATURES. THE FLOOD
RISK WILL BE A COMBINATION OF SNOWMELT AND RAINFALL. MINOR FLOOD
RISK FOR THE SMALLER STREAMS AND CREEKS IS HIGHLIGHTED IN HWO AND
WILL CONTINUE TO BE MONITORED CLOSELY.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD/LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...FITZGERALD/LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...STEINBUGL
HYDROLOGY...LAMBERT
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
232 AM CST MON FEB 1 2016
.DISCUSSION...
COLD FRONT JUST ENTERING NORTHWEST MIDDLE TENNESSEE AT THIS TIME
WITH SHOWERS ALONG FRONTAL BOUNDARY. THERE HAS A FEW LIGHTNING
STRIKES IN WESTERN TENNESSEE BUT NONE SO FAR HERE IN MIDDLE
TENNESSEE. FRONT WILL MOVE SLOWLY THROUGH THE MID STATE TODAY AND
PULL UP DOWN ALONG THE ALABAMA BORDER AROUND 00Z BEFORE RETURNING
TONIGHT AS A WARM FRONT AND BE NORTH OF THE MID STATE ON TUESDAY.
COOLER TODAY BUT MUCH WARMER ON TUESDAY WITH HIGHS AROUND 70 IN
MANY AREAS.
POWERFUL UPPER JET IN SOUTHWESTERN U.S. THIS MORNING WITH SURFACE
LOW GETTING ORGANIZED ACROSS THE FOUR CORNERS WILL BECOME BETTER
ORGANIZED OVER NORTHEAST NEW MEXICO AND SOUTHEAST COLORADO DURING
THE DAY. THERE ARE SOME MINOR DIFFERENCES IN SURFACE LOW TRACK BUT
REGARDLESS MID STATE IS WELL WITHIN WARM SECTOR COME TUESDAY INTO
TUESDAY NIGHT. JET DYNAMICS ARE VERY STRONG WITH AN UPPER LEVEL
SPEED MAX IN EXCESS OF 150 KNOTS AT 03Z TUESDAY EVENING FROM
ARKANSAS TO INDIANA. MID LEVEL JET ON THE ORDER OF 120 KNOTS WITH
60 TO 70 KNOT LOW LEVEL JET. SURFACE LOW UNDERGOES CYCLOGENSIS AS
IT MOVES NORTHEAST TUESDAY NIGHT INTO ILLINOIS. PARAMETERS WILL BE
SET FOR SEVERE WEATHER HERE IN MIDDLE TENNESSEE TUESDAY EVENING
WHICH WILL CONTINUE PAST MIDNIGHT WITH DAMAGING WINDS BEING THE
MAIN THREAT HOWEVER A TWISTER OR TWO LOOKS TO BE POSSIBLE. THE
SIGNIFICANT TORNADO PARAMETER CLIMBS TO +2 IN MIDDLE TENNESSEE
TUESDAY EVENING FROM 00Z TO 06Z.
AS FAR AS TIMING...EXPECT TO SEE A LINE OF CONVECTION (SQUALL
LINE) DOWN THROUGH EASTERN ARKANSAS AROUND 18Z (NOON) TUESDAY BUT
COULD BE DELAYED DEVELOPING DUE TO CAPPING. ONCE FORMED LINE WILL
WORK EAST INTO WESTERN TENNESSEE AROUND 21Z (3 PM) AND ALONG THE
TENNESSEE RIVER BY 00Z (6 PM) AND THEN IT LOOKS LIKE THE LINE
SLOWS EASTWARD MOVEMENT THROUGH WESTERN MIDDLE TENNESSEE BUT
SHOULD BE NEARING INTERSTATE 65 BY MIDNIGHT AND ALONG PLATEAU BY 09Z
(3 AM).
DRY WITH MORE TYPICAL WINTER TIME TEMPERATURES WEDNESDAY THROUGH
THE WEEKEND.
&&
.AVIATION...
06Z TAF DISCUSSION.
BNA/CKV/CSV...SURFACE FRONT HAS ALMOST REACHED LAND-BETWEEN-THE-
LAKES, STILL WITH VERY LITTLE ACTIVITY HAVING FORMED AHEAD OF THE
BOUNDARY. HRRR CONTINUES TO SHOW ECHOES INCREASING OVERNIGHT AS
THE FRONT PUSHES EASTWARD, SO WILL GRADUALLY INCREASE SHRA IN THE
TAF`S, ESPECIALLY FOR BNA & CSV, AS THE MODELS HINT THAT POP`S
WILL INCREASE IN AREAS FURTHER DOWNSTREAM FROM THE CURRENT
FRONTAL POSITION. EXPECT CIGS TO DROP ACCORDINGLY, LIKELY
REMAINING VFR AT CKV BUT BECOMING AT LEAST MVFR AT BNA & CSV FOR
SEVERAL HOURS LATER TONIGHT AND TOMORROW.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 60 51 70 44 52 / 60 10 50 90 20
CLARKSVILLE 56 49 69 43 49 / 20 10 70 80 10
CROSSVILLE 57 48 66 49 51 / 70 20 30 90 30
COLUMBIA 61 53 69 44 51 / 60 20 60 90 10
LAWRENCEBURG 61 53 69 45 52 / 60 20 50 90 10
WAVERLY 57 52 70 42 50 / 30 20 80 90 10
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM/AVIATION........07
LONG TERM..................01/BOYD
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
308 AM EST MON FEB 1 2016
.SHORT TERM (TODAY AND TONIGHT)...
A COLD FRONT CURRENTLY STRETCHES SOUTHWESTWARD FROM CINCINNATI TO
BOWLING GREEN TO JUST EAST OF MEMPHIS. RADAR IMAGERY INDICATES
SCATTERED TO NUMEROUS SHOWERS AHEAD OF THIS BOUNDARY WITH A FEW
LIGHTNING STRIKES SHOWING UP FROM TIME TO TIME. CURRENT WATER VAPOR
IMAGERY AND RAP UPPER AIR ANALYSIS INDICATES AN UPPER LEVEL TROUGH
ACROSS THE GREAT LAKES REGION WITH A SHORTWAVE RIDGE ACROSS THE
CENTRAL PLAINS. TEMPERATURES HAVE REMAINED UP ACROSS THE AREA THANKS
TO CONTINUED SOUTHERLY FLOW AHEAD OF THE FRONT. TEMPERATURES AS OF 3
AM...ARE MAINLY IN THE MID 50S TO LOW 60S WHICH ARE HIGHER THAN THE
AVERAGE HIGHS FOR THIS TIME OF THE YEAR.
FOR TODAY...THE COLD FRONT AND PRECIPITATION WILL MAKE SLOW PROGRESS
ACROSS THE AREA AS THE UPPER LEVEL TROUGH RACES OFF QUICKLY TO THE
NORTHEAST. THE FRONT WILL TAKE ON MORE OF A EAST TO WEST ORIENTATION
AS THE UPPER LEVEL FLOW BECOMES PARALLEL TO THE SURFACE BOUNDARY. PW
VALUES WILL INCREASE TO NEAR 1 INCH BY THIS AFTERNOON...WHICH IS
WELL OVER THE 90TH PERCENTILE FOR EARLY FEBRUARY. THEREFORE...EXPECT
NUMEROUS TO WIDESPREAD SHOWERS ACROSS THE AREA TODAY. SOME OF THE
MODELS INDICATE A LITTLE WEAK INSTABILITY THIS AFTERNOON BUT THE
UPPER SUPPORT IS EXITING SO HAVE JUST GONE WITH SHOWERS FOR NOW. THE
FRONT WILL STALL ACROSS THE AREA LATER TONIGHT WITH UPPER FLOW
CONTINUING TO BE PARALLEL TO THE SURFACE BOUNDARY. DRIER AIR MOVES
INTO THE MID AND UPPER LEVELS AS SOME OF THE MODELS ARE SHOWING WEAK
RIDGING ALOFT. HOWEVER...THE LOWER LEVELS REMAIN SATURATED WITH
LIGHT RAIN/DRIZZLE EXPECTED TO CONTINUE THROUGHOUT THE NIGHT. LIGHT
WINDS TONIGHT ALONG THE STALLED BOUNDARY WILL ALSO SETUP THE
CONDITIONS FOR FOG TO DEVELOP DURING THE OVERNIGHT HOURS.
.LONG TERM (TUESDAY THROUGH SUNDAY)...
AHEAD OF AN APPROACHING COLD FRONT...SHOULD SEE A FEW SCATTERED
SHOWERS DEVELOP OVER THE REGION TUESDAY AFTERNOON. THE FRONT WILL
REACH INTO THE REGION LATE TUESDAY NIGHT INTO WEDNESDAY MORNING.
MAIN CONCERN WITH THIS FRONT WILL BE STRONG 850MB WINDS. EXPECT
WINDS TO INCREASE SIGNIFICANTLY TUESDAY NIGHT...ESPECIALLY OVER
HIGHER ELEVATIONS. SUSTAINED WINDS OF 30 TO 40 MPH WITH GUSTS OF 50
TO 60 MPH CAN BE EXPECTED. WILL LIKELY NEED A WIND ADVISORY OR HIGH
WIND WARNING FOR THIS TIME PERIOD. ALSO OF CONCERN WITH THE FRONTAL
PASSAGE WILL BE THE POTENTIAL FOR A LINE OF SHOWERS AND
THUNDERSTORMS TO MOVE THROUGH. THERE WILL BE LITTLE INSTABILITY TO
WORK WITH BUT GOOD SPEED SHEAR AND UPPER LEVEL SUPPORT FOR THE
DEVELOPMENT OF THUNDERSTORMS. IF ANY OF THESE STORMS CAN REACH INTO
THE STRONG 850MB WINDS...THEY COULD PRODUCE STRONG...DAMAGING WINDS
AND A STRAY SEVERE STORM IS NOT OUT OF THE QUESTION. A FEW SHOWERS
MAY LINGER ACROSS THE HIGHER TERRAIN INTO THURSDAY AS THE UPPER LOW
ROTATES IN ADDITIONAL MOISTURE AND WEAK LIFT. WILL BE UNDER DRY
NORTHWESTERLY FLOW ON FRIDAY WITH WEAK RIDGING ON SATURDAY. FOR
SUNDAY...MODELS HINTING AT A TROUGH APPROACHING THE AREA...BUT FOR
NOW WILL LEAVE DRY. AS FOR TEMPERATURES....EXPECT VERY WARM
CONDITIONS ON TUESDAY...AHEAD OF THE COLD FRONT...BEHIND THE FRONT
AND THROUGH THE REST OF THE EXTENDED...WE SHOULD GENERALLY SEE NEAR
NORMAL TEMPERATURES.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 67 54 69 54 / 50 30 30 100
KNOXVILLE MCGHEE TYSON AIRPORT, TN 63 49 67 53 / 80 20 20 90
OAK RIDGE, TN 61 49 67 53 / 80 20 20 90
TRI CITIES AIRPORT, TN 59 44 64 52 / 80 30 20 70
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
MA/MJB
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1114 PM CST SUN JAN 31 2016
.UPDATE...
FOR 06Z AVIATION DISCUSSION.
&&
.DISCUSSION...
A NARROW LINE OF SHOWERS WITH MODERATE TO HEAVY DOWNPOURS WAS
PUSHING INTO NORTHWEST MIDDLE TN SHORTLY AFTER 8 PM THIS EVENING.
ANOTHER BAND OF SHOWERS WAS LOCATED FURTHER TO THE NORTHWEST, NEAR
THE OHIO RIVER VALLEY, ALONG A COLD FRONT.
STILL LOOKS LIKE THE COLD FRONT WILL BE NEAR OUR NORTHWESTERN
COUNTIES BY 06Z, AND IN THE NASHVILLE AREA BY 09Z, AND PUSH INTO
SOUTHERN AND EASTER AREAS LATE TONIGHT AND EARLY MONDAY MORNING.
SHOWERS WILL BECOME LIKELY IN MOST AREAS OVERNIGHT, ALONG WITH A
SLIGHT CHANCE FOR THUNDERSTORMS.
HAVE UPDATED FORECAST GRIDS TO MORE CLOSELY REFLECT LATEST TRENDS
AND FORECAST MOVEMENT OF COLD FRONT ACROSS THE AREA TONIGHT.
EVEN THOUGH POPS AND OVERNIGHT MIN TEMPS REMAIN PRETTY MUCH
UNCHANGED, WILL GO AHEAD AND UPDATE PRODUCT SUITE TO CATCH THESE
MINOR CHANGES IN THE MORE DISCRIMINATING PRODUCTS, LIKE THE PFM
AND AFM.
&&
.AVIATION...
06Z TAF DISCUSSION.
BNA/CKV/CSV...SURFACE FRONT HAS ALMOST REACHED LAND-BETWEEN-THE-
LAKES, STILL WITH VERY LITTLE ACTIVITY HAVING FORMED AHEAD OF THE
BOUNDARY. HRRR CONTINUES TO SHOW ECHOES INCREASING OVERNIGHT AS
THE FRONT PUSHES EASTWARD, SO WILL GRADUALLY INCREASE SHRA IN THE
TAF`S, ESPECIALLY FOR BNA & CSV, AS THE MODELS HINT THAT POP`S
WILL INCREASE IN AREAS FURTHER DOWNSTREAM FROM THE CURRENT
FRONTAL POSITION. EXPECT CIGS TO DROP ACCORDINGLY, LIKELY
REMAINING VFR AT CKV BUT BECOMING AT LEAST MVFR AT BNA & CSV FOR
SEVERAL HOURS LATER TONIGHT AND TOMORROW.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM/AVIATION........08
LONG TERM..................19
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
350 AM CST MON FEB 1 2016
.DISCUSSION...
AT 3 AM...A WEAK BOUNDARY SLICED THROUGH THE EXTREME NORTHERN PART
OF SE TX. THE SFC DEW PT AT CALDWELL WAS 46 AND IT WAS 61 AT KCLL
AND 64 AT BRENHAM. THE BOUNDARY WILL WAFFLE A BIT NORTH BEFORE
EVENTUALLY DISSIPATING AND HIGHER DEW PT AIR WILL FILTER TO THE
NORTH. THE OTHER DILEMMA THIS MORNING IS FOG. HRRR IS HANDLING IT
PRETTY WELL AND IS DEPICTING TWO AREAS OF CONCERN. THE FIRST IS
THE SEA FOG AT THE COAST. AS THE FOG MOVES INLAND...THERE APPEARS
TO BE JUST ENOUGH WIND AT 500-1000 FEET TO LIFT THE FOG INTO LIFR
CIGS. THE SECOND AREA OF CONCERN IS OVER THE NW ZONES WHERE
VISIBILITIES HAVE WAVERED BETWEEN 1/2 AND 2 MILES IN FOG. THE HRRR
SHOWS THAT AREA IMPROVING BETWEEN 11-13Z SO WILL HOLD OFF ON ANY
ADVISORY AT THIS TIME. THE HRRR KEEPS THE SEA FOG IN PLACE ALONG
THE COAST FOR MOST OF THE DAY. THERE WILL BE SIGNIFICANT
IMPROVEMENT IN VSBY FOR THE INLAND PORTIONS OF THE COASTAL
COUNTIES BY 10 AM OR SO...BUT THE IMMEDIATE COAST COULD KEEP THE
FOG FOR MUCH OF THE DAY. ALTHOUGH ON THE FENCE...HAVE DECIDED TO
CANCEL THE DENSE FOG ADVISORY FOR WHARTON...FT BEND...HARRIS AND
LIBERTY COUNTIES AS OBSERVATIONS AND WEB CAMERAS SIMPLY DON`T
SUPPORT RESTRICTED VSBYS LESS THAN A 1/4 MILE. WILL MAINTAIN THE
ADVISORY ALONG THE IMMEDIATE COAST.
TEMPS ARE IN THE LOWER/MID 60S SOUTH OF THE BOUNDARY SO IT WON`T
TAKE MUCH HEATING TO BUMP TEMPS INTO THE UPPER 70S THIS AFTERNOON.
NAM/GFS FCST SOUNDINGS DIFFER SIGNIFICANTLY WITH SKY COVER TODAY
AS THE NAM KEEPS THINGS CLOUDY WHILE THE GFS BREAKS OUT SOME AFTN
SUN. A STRONG CAPPING INVERSION IN PLACE SHOULD LIMIT MIXING SO
OPTED TOWARD MORE CLOUDS TODAY.
AN AREA OF LOW PRESSURE OVER SE COLORADO WILL STRENGTHEN TONIGHT
AND TIGHTEN THE GRADIENT SO WINDS SHOULD BEGIN TO INCREASE THIS
AFTERNOON INTO TONIGHT. AS THE LOW PUSHES TO THE NE...A WEAK PRE
FRONTAL TROUGH OR WHAT LOOKS LIKE A DRY LINE SHOULD CROSS THE
AREA. MOISTURE IS LIMITED WITH PW VALUES ONLY AROUND AN INCH.
ATMOSPHERE REMAINS CAPPED SO JUST EXPECTED A BROKEN LINE OF WEAK
SHOWERS TONIGHT INTO EARLY TUESDAY. RAINFALL TOTALS WITH SYSTEM
WILL BE VERY LIGHT WITH MOST LOCATIONS PROBABLY GETTING JUST A
FEW HUNDREDTHS OF AN INCH. A SURGE OF MUCH COLDER TEMPERATURES
DOESN`T ARRIVE UNTIL TUESDAY EVENING. HIGH PRESSURE WILL MOVE
ACROSS THE STATE ON WED/THURS AND EAST OF THE STATE BY FRIDAY
AFTERNOON. THIS FEATURE WILL BRING MUCH COOLER CONDITIONS AND
CLEAR SKIES WED-FRI. A WEAK S/WV TROUGH WILL DIG INTO TEXAS FRI
NITE OR SATURDAY. NOT MUCH MOISTURE FOR THIS SYSTEM TO WORK WITH
BUT ADDED 20/30 POPS AS THE FORCING WITH THIS FEATURE LOOKS RATHER
STRONG. HIGHER POPS OVER THE SOUTHERN HALF OF THE REGION CLOSER TO
THE BEST FORCING AND DEEPER MSTR. 43
&&
.MARINE...
AREAS OF DENSE SEA FOG WILL POSSIBLY LIFT THIS AFTERNOON...ALTHOUGH
PATCHY FOG WILL LIKELY CONTINUE. WINDS WILL ALSO INCREASE THIS
AFTERNOON AND EVENING AND HELP TO DISPERSE ANY WIDESPREAD FOG THAT
TRIES TO DEVELOP. STILL THINK THAT THERE WILL BE PATCHY FOG THROUGH
THE NIGHT. THERE IS A GOOD CHANCE THE SEA FOG WILL BECOME DENSE
AGAIN LATE TONIGHT AND EARLY TUESDAY MORNING. FACTORS CONTRIBUTING
WILL BE DIMINISHING WINDS AHEAD OF A COLD FRONT AND POOLING OF
MOISTURE ALONG THE FRONTAL BOUNDARY. IN ANY EVENT...THE FOG THREAT
WILL END WITH THE PASSAGE OF THE FRONT. THE FRONT IS EXPECTED TO
MOVE THROUGH THE BAYS AND OFF THE COAST AROUND OR JUST AFTER
SUNRISE. A REINFORCING FRONT WILL THEN PUSH OFF THE COAST EARLY
TUESDAY EVENING. MODERATE OFFSHORE WINDS WILL DEVELOP BEHIND THE
SECOND FRONT.
40
&&
.CLIMATE...
JANUARY HAS COME TO AN END AND THE AVERAGE TEMPERATURE FOR THE
MONTH WAS NEAR TO SLIGHTLY COOLER THAN NORMAL. RAINFALL ACROSS SE
TEXAS WAS WELL BELOW NORMAL WITH MANY LOCATIONS 2 INCHES DRIER
THAN THE 30 YEAR NORMALS. 43
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 56 68 39 56 / 10 20 20 0 0
HOUSTON (IAH) 78 63 74 42 60 / 10 30 30 0 0
GALVESTON (GLS) 69 62 72 48 59 / 10 30 40 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: BRAZORIA...CHAMBERS...GALVESTON...
JACKSON...MATAGORDA.
GM...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1110 PM CST SUN JAN 31 2016
.AVIATION...
/06Z TAFS/
PATCHY TO AREAS OF FOG HAVE ALREADY DEVELOPED ACROSS THE COASTAL
PLAINS COUNTIES WITH FOG/STRATUS CLOUDS EXPECTED TO PUSH TO THE
NORTH LATER TONIGHT INTO MONDAY MORNING. LATEST HRRR LAYER TOTAL
CLOUD COVER AND CIRA SIMWRF FOG PRODUCTS SUGGEST THE EDGE OF THE
LOW STRATUS CLOUD DECK TO AFFECT THE I-35 TERMINALS AROUND 12Z/13Z
TIME FRAME. ALSO...AREA FORECAST SOUNDINGS SUGGEST LOW CIGS UNDER
A SHALLOW LAYER NEAR THE SURFACE TO FEW HUNDRED FEET.
THEREFORE...OPTED TO INTRODUCE A TEMPO GROUP FOR ALL I-35 SITES
WITH LIFR CONDITIONS. ACROSS KDRT...VFR CONDITIONS ARE EXPECTED
THROUGH THE PERIOD. AROUND 16Z MONDAY...WELL-MIX LAYER TO BRING AN
END TO LOW CIGS/VBSYS. SOUTHERLY WINDS OF 10 TO 20 KNOTS ARE
EXPECTED MONDAY AFTERNOON WITH GUSTS UP TO 25 KNOTS AHEAD OF A
COLD FRONT. A FRONTAL BOUNDARY IS EXPECTED TO PUSH ACROSS THE AREA
MONDAY NIGHT WITH A WIND SHIFT EXPECTED FROM THE NORTHWEST AROUND
01Z TUESDAY FOR KDRT AND ALONG THE I-35 SITES BETWEEN 06Z FOR KSAT
AND KSSF AND 07Z FOR KAUS.
&&
.PREV DISCUSSION... /ISSUED 934 PM CST SUN JAN 31 2016/
UPDATE...
FORECAST FOR TONIGHT IS MOSTLY ON TRACK. ONLY ADJUSTMENTS WERE
MADE TO THE WEATHER GRIDS AND THE HOURLY GRIDS TO RE-TREND THEM
BASED ON CURRENT OBSERVATIONS. THE RECENT RUNS OF THE HRRR AS WELL
AS THE 00Z RUN OF THE NAM MODEL BRING FOG INTO THE I-35 CORRIDOR
BY MORNING SO DID EXPAND MENTION OF PATCHY FOG. ALSO ADDED AREAS
OF FOG TO THE COASTAL PLAINS. WHILE STATIONS ALONG THE TEXAS COAST
ARE ALREADY REPORTING VISIBILITY 1 MILE OR LESS...THE INLAND OBSERVING
STATION FROM VICTORIA TO LA GRANGE HAVE ALREADY DROPPED TO 3 TO 5
MILES.
THE OTHER BIG ADDITION TO THE EVENING UPDATE WAS THE ISSUANCE OF A
FIRE WEATHER WATCH FOR FOUR COUNTIES ALONG THE RIO GRANDE PLAINS
AND WESTERN EDWARDS PLATEAU. WINDS WILL BE GUSTY TO 15 TO 20 MPH
AHEAD OF THE APPROACHING FRONT MONDAY AFTERNOON. RELATIVE
HUMIDITY VALUES WILL BOTTOM OUT IN THE TEENS TO CREATE A FEW
HOURS OF CRITICAL FIRE WEATHER IN VAL VERDE...KINNEY...MAVERICK AND
EDWARDS COUNTIES. FUEL MOISTURE IS THE BIG QUESTION FOR THESE
WESTERN AREAS...BUT THE LAST SIGNIFICANT RAINS THIS AREA
EXPERIENCED WERE BACK IN EARLY JANUARY. FOR THIS REASON WENT AHEAD
AND ISSUED THE FIRE WEATHER WATCH. SUBSEQUENT SHIFTS WILL EXAMINE
THE TRENDS AND DETERMINE WHETHER A RED FLAG WARNING WILL BE
NEEDED. FIRE WEATHER CONCERNS WILL CONTINUE INTO THE DAY ON
TUESDAY ONCE THE FRONT MOVES THROUGH. A FEW OF THE RIO GRANDE
PLAINS AND EDWARDS PLATEAU COUNTIES...EDWARDS...REAL... VAL
VERDE...KERR AND DIMMIT ARE CURRENTLY UNDER COUNTY WIDE BURN
BANS.
PREV DISCUSSION... /ISSUED 614 PM CST SUN JAN 31 2016/
AVIATION...
/00Z TAFS/
VFR CONDITIONS ARE EXPECTED THROUGH 07Z MONDAY FOR THE I-35
TERMINALS. KDRT SHOULD REMAIN VFR THROUGH THE FORECAST PERIOD.
MVFR/IFR CONDITIONS ARE EXPECTED OVERNIGHT INTO MONDAY MORNING FOR
THE I-35 SITES AS PATCHY FOG AND STRATUS CLOUDS FORM ALONG AND
EAST OF INTERSTATE 35. ONCE AGAIN...BOTH GFS LAMP AND MOS GUIDANCE
SUGGEST SEVERAL HOURS OF LIFR CONDITIONS FOR THE I-35 AIRPORTS
FROM 11Z TO 16Z MONDAY. BELIEVE THESE MODELS ARE OVER DOING LOW
VBSYS FOR THAT PERIOD WITH SIMILAR CONDITIONS EXPECTED AS EARLIER
THIS MORNING. CAN NOT RULE AN HOUR OR TWO OF LIFR AROUND KAUS FOR
THE 12Z TO 13Z TIME FRAME...HOWEVER IFR CONDITIONS ARE EXPECTED TO
BE TO MAIN FLIGHT CONDITIONS FOR MONDAY MORNING TIL 15Z.
VFR CONDITIONS RETURN TO THE I-35 SITES AFTER 15Z MONDAY AND
REMAIN THROUGH THE FORECAST PERIOD. BREEZY CONDITIONS ARE EXPECTED
ON MONDAY AHEAD OF A COLD FRONT. SOUTHERLY WINDS OF 1O TO 20 KNOTS
ARE EXPECTED WITH GUSTS UP TO 30 KNOTS. IN THE WAKE OF THE
FRONT...WINDS WILL SHIFT TO THE NORTHWEST BY MIDNIGHT TUESDAY FOR
KSAT AND KSSF AND 07 TUESDAY FOR KAUS. WIND SHIFT TO THE NW WILL
OCCUR AROUND 01Z TUESDAY FOR KDRT.
PREV DISCUSSION... /ISSUED 324 PM CST SUN JAN 31 2016/
SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...
THIS AFTERNOON...A DRY LINE SPANNED FROM EAGLE PASS TO HONDO TO
KILLEEN RESULTING IN DRY GUSTY WINDS OUT OF THE WEST AND
RELATIVELY LIGHT WINDS EAST OF THE I35 CORRIDOR AND COASTAL
PLAINS. DEWPOINTS ON THE PLATEAU WERE IN THE 20S AND AS HIGH AS 60
IN VICTORIA. HIGHS WERE IN THE UPPER 70S TO MID 80S WITH CLEAR
SKIES ACROSS THE REGION.
A VERY SIMILAR FORECAST TONIGHT COMPARED TO YESTERDAY WITH
POTENTIAL FOG DEVELOPMENT ON THE MOIST SIDE OF THE DRY LINE AND
CLOUD COVER IN THE MORNING...PERHAPS A BIT LESS COVERAGE THAN THIS
MORNING.
TOMORROW WILL BE THE LAST DAY WITH WELL ABOVE NORMAL TEMPERATURES.
OVERALL THE FORECAST HAS NOT CHANGED SUBSTANTIALLY AS EXPECTATIONS
ARE STILL FOR HIGHS IN THE MID 80S FOR MANY AREAS AND GUSTY WINDS
IN THE AFTERNOON HOURS. MOS GUIDANCE INCREASES THE WIND FIELDS
SUBSTANTIALLY LATE MORNING AND AROUND THE NOONTIME HOUR. WITH A
PRE FRONTAL SURFACE LOW AHEAD OF THE APPROACHING FRONTAL
SYSTEM...THE PGF WILL TIGHTEN AS THE LOW PASSES TO THE NORTH AND
BRING 15-25 MPH WINDS GUSTING TO 30 MPH.
CONCERNING FIRE WEATHER CONDITIONS...IT WAS DECIDED NOT TO ISSUE A
FIRE WEATHER WATCH FOR ANY OF OUR COUNTIES DUE TO THE FACT THAT
NO LOCATION IS FORECAST TO RECEIVE ALL THREE NECESSARY CRITERIA
FOR A RFW. WHILE LOCATIONS IN NORTHERN EDWARDS AND VAL VERDE AND
ALONG THE RIO GRANDE WILL EXPERIENCE THE WINDS AND MIN RH CRITERIA
OF 20 PERCENT OR BELOW...THE DISQUALIFYING FACTOR IS THE MOISTURE
CONTENT OF THE FUELS STILL NOT BEING DRY ENOUGH. WHEREAS IN THE
HILL COUNTRY...FUELS ARE A CATEGORY DRIER AND SHOULD SEE WINDS
OVER 20 MPH...BUT RH VALUES PROBABLY WONT QUITE REACH THE
CRITICAL 20 PERCENT MARK. THUS...THE FORECAST OF NEAR CRITICAL WAS
MAINTAINED FOR THESE AREAS.
LONG TERM (TUESDAY THROUGH SUNDAY)...
THE AFOREMENTIONED STRONG COLD FRONT CONTINUES TO BE PROGGED TO
PUSH INTO THE CWA LATE MONDAY NIGHT AND EARLY TUESDAY MORNING.
WITH STRONG HIGH PRESSURE BEHIND THE FRONT...WIND ADVISORY LEVEL
WINDS WILL BE POSSIBLE BY LATE MORNING AND THROUGH AT LEAST THE
EARLY AFTERNOON. IT WILL ALSO PLUNGE RH VALUES DOWN TO BELOW 20
PERCENT FOR WEST OF THE I35 CORRIDOR AND STILL BELOW 30 PERCENT
FARTHER EAST.
THIS SHOULD RESULT IN THE MOST SIGNIFICANT FIRE WEATHER THREAT OF
THE LAST FEW DAYS. WITH MULTIPLE DAYS OF IDEAL FUEL DRYING
CONDITIONS...AND THE PROSPECT OF CRITICAL WINDS AND RH
VALUES...CRITICAL FIRE WEATHER CONDITIONS APPEAR TO BE LIKELY FOR
THE WESTERN HALF OF THE CWA. DID WANT TO HOLD OFF ON A WATCH THIS
SHIFT MOSTLY DUE TO THE DESIRE TO EVALUATE THE OBSERVED FUELS
ANALYSIS FOR TODAY...LATER THIS EVENING. THAT INFORMATION SHOULD
BE ABLE TO PROVIDE A BETTER IDEA OF THE SPATIAL EXTENT THE
POSSIBLE WATCH WOULD COVER...IF CONDITIONS CONTINUE TO WARRANT THE
NEED FOR THE PRODUCT.
BEYOND TUESDAY HOWEVER...MUCH COOLER TEMPERATURES ARE EXPECTED
WHICH WILL END THE FIRE WEATHER THREAT AS RH VALUES RECOVER. OUR
NEXT POTENTIAL SYSTEM APPEARS TO BE SATURDAY WITH A DEEP DIVING
UPPER LOW...HOWEVER ECMWF OUTCOMES PRODUCE SIGNIFICANT QPF AND GFS
IS FULLY DRY. THIS TYPE OF MODEL DISCREPANCY IS AT BEST SUSPECT SO
FOR NOW...WILL WAIT FOR A BIT BETTER AGREEMENT BEFORE ADDRESSING
THIS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 50 79 53 70 40 / 0 0 10 - -
AUSTIN BERGSTROM INTL AIRPORT 45 78 52 70 36 / 0 0 10 - -
NEW BRAUNFELS MUNI AIRPORT 45 82 52 72 38 / 0 0 10 10 -
BURNET MUNI AIRPORT 45 78 47 66 35 / 0 0 10 - -
DEL RIO INTL AIRPORT 45 87 48 69 40 / 0 0 0 0 0
GEORGETOWN MUNI AIRPORT 46 77 49 69 37 / 0 0 10 - -
HONDO MUNI AIRPORT 40 84 50 72 38 / 0 0 - - -
SAN MARCOS MUNI AIRPORT 46 79 52 70 38 / 0 0 10 10 -
LA GRANGE - FAYETTE REGIONAL 50 77 55 70 40 / 0 0 20 20 -
SAN ANTONIO INTL AIRPORT 48 81 53 72 40 / 0 0 10 - -
STINSON MUNI AIRPORT 44 84 54 72 40 / 0 0 10 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
&&
$$
MESOSCALE/AVIATION...17
SYNOPTIC/GRIDS...TREADWAY
PUBLIC SERVICE/DATA COLLECTION...TREADWAY
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1152 PM EST SUN JAN 31 2016
.SYNOPSIS...
A MILD SOUTHWEST FLOW WILL CONTINUE THROUGH MONDAY MORNING. BY
MONDAY AFTERNOON...A WEAK COLD FRONT WILL CROSS OVERHEAD TO
PROVIDE A CHANCE OF SHOWERS...BEFORE LIFTING BACK NORTH AS A WARM
FRONT ON TUESDAY NIGHT. MORE WIDESPREAD RAIN SHOULD ARRIVE FROM A
STRONGER COLD FRONT ON WEDNESDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 940 PM EDT SUNDAY...
AS EXPECTED A WIDE VARIETY OF TEMPERATURES TONIGHT BASED ON
ELEVATION. TYPICAL LOWER ELEVATION COOL SPOTS ARE ALREADY DOWN
INTO THE UPPER 30S...MEANWHILE THE HIGHER ELEVATIONS ARE STILL
HOLDING IN THE UPPER 40S TO LOWER 50S AT THIS HOUR MAKING FOR A
TRICKY TEMPERATURE FORECAST TONIGHT. LATEST HRRR RUN BRINGS PRECIP
TO OUR WESTERN DOORSTEP AROUND 16Z MONDAY MORNING WHICH ALIGNS
WELL WITH THE PREVIOUS FORECAST SO NO CHANGES WERE MADE THERE.
AS OF 340 PM EST SUNDAY...
A SOUTHWEST FLOW FROM THE WESTERN PERIPHERY OF HIGH PRESSURE
LOCATED WELL OFFSHORE...CONTINUES TO PUMP WARM AIR OVER THE MID
ATLANTIC. PLENTY OF SOLAR HEATING OCCURRED TODAY UNDER MOSTLY
SUNNY SKIES WITH JUST SOME SCATTERED CIRRUS CLOUDS. IN
RESPONSE...TEMPERATURES HAVE REBOUNDED NICELY FROM THE CHILLY
START THIS MORNING...SO HIGHS WILL REACH THE UPPER 50S TO THE
UPPER 60S. IT IS A NICE AFTERNOON TO GET OUTSIDE AND ENJOY THE
SUNSHINE AND WARMTH FOR THE LAST DAY OF JANUARY...BECAUSE IT WILL
NOT LAST LONG WHEN FEBRUARY BEGINS.
BY TONIGHT...CLOUDS WILL INCREASE FROM THE WEST...AS A WEAK COLD
FRONT APPROACHES THE APPALACHIAN MOUNTAINS. A DECENT LOW LEVEL
JET FROM THE SOUTHWEST AT 40 KT...SHOULD BRING MORE MOISTURE.
WIND GUSTS UP TO 30 KT ARE POSSIBLE ALONG THE HIGHEST TERRAIN.
THE WARM AIR ADVECTION...THICKENING CLOUD COVER...AND AMPLE MIXING
WOULD SUGGEST THAT LOWS WILL NOT DROP MUCH TONIGHT. HOWEVER...A
LITTLE SNOW COVER STILL REMAINS WEST OF THE BLUE RIDGE...AND THE
MIXING WILL NOT BE AS STRONG TO THE EAST. THUS...LOWS TONIGHT ARE
TRICKY DUE TO THESE COMPETING FACTORS...BUT IT SEEMS THAT THE
UPPER 30S TO THE UPPER 40S IS THE BEST RANGE TO UTILIZE.
RAIN SHOWERS SHOULD ARRIVE ON MONDAY MORNING ALONG THE WESTERN
SLOPES...AND SPREAD EASTWARD DURING THE DAY. POPS WERE INCREASED
TO HIGHLIGHT THE INCREASING CONFIDENCE OF RAIN IN THE LATEST
MODEL SOLUTIONS. QPF WILL ONLY REACH A TENTH TO A THIRD OF AN INCH
WEST OF THE BLUE RIDGE...AND LOWER AMOUNTS SHOULD FALL TO THE
EAST. THE MODELS HINT THAT SOME OF THE MOISTURE COULD CROSS OVER
THE BLUE RIDGE...BUT IT MAY STRUGGLE TO REACH SOUTHSIDE VIRGINIA
AND THE NORTH CAROLINA PIEDMONT. CLOUDY SKIES AND SHOWERS SHOULD
KEEP HIGHS IN THE UPPER 40S TO THE MID 50S WEST OF THE BLUE RIDGE.
IN THE PIEDMONT...LOWER CHANCES OF RAIN AND PEEKS OF SUNSHINE
COULD PUSH HIGHS INTO THE UPPER 50S TO THE MID 60S.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 407 PM EST SUNDAY...
SURFACE COLD FRONT WILL DRIFT THROUGH THE FORECAST AREA MONDAY
EVENING...WINDS BECOMING NORTHERLY...THEN TENDING NORTHEASTERLY
OVERNIGHT. TEMPERATURES WILL TAKE A TUMBLE INTO THE 40S...POSSIBLY
REACHING THE UPPER 30S ACROSS THE NORTHERN CWA BY DAYBREAK
TUESDAY...BUT NOTHING BELOW FREEZING. IN SPITE OF THE LINGERING LOW
LEVEL CLOUD COVER THERE WILL BE LITTLE OR NO UPPER LEVEL SUPPORT FOR
PRECIP PRODUCTION...SO ANY THREAT FOR RAIN MONDAY NIGHT IS LESS THAN
50 PERCENT.
FOR TUESDAY...FRONT WILL BE STALLED ACROSS THE CAROLINAS LEAVING
MOST OF OUR CWA WEDGED ON THE COOL SIDE OF THE FRONT WITH SHALLOW
AREA OF HIGH PRESSURE EXTENDING NORTHEAST ALONG THE EAST SIDE OF THE
APPALACHIANS INTO NEW ENGLAND. A PERSISTENT NORTHEAST TO EASTERLY
SORT OF WIND WILL KEEP LOW LEVEL MOISTURE/CLOUDS BANKED UP AGAINST
THE EAST SIDE OF THE MOUNTAINS THROUGHOUT THE DAY...TEMPERATURES
RISING VERY LITTLE. ON THE FLIP SIDE...WEST SIDE...OF THE
APPALACHIAN DIVIDE...THERE SHOULD BE VERY LITTLE INFLUENCE FROM THE
COOL WEDGE...SO TEMPERATURES ACROSS THE TENNESSEE VALLEY SHOULD WARM
BACK INTO THE 50S/60S.
WEDNESDAY WILL BE THE MOST ACTIVE WEATHER DAY THIS WEEK AS A STRONG
STRONG STORM SYSTEM MOVES FROM THE UPPER MIDWEST INTO THE GREAT
LAKES...ITS ASSOCIATED COLD FRONT SWEEPING EAST AND THROUGH OUR
FORECAST AREA. STRONG SOUTHWEST FLOW AHEAD OF THE FRONT WILL BRING
DEEPER MOISTURE BACK INTO THE REGION AS EARLY AS TUESDAY NIGHT...THE
SOUTHWEST WINDS PUSHING THE OLD STALLED FRONT TO OUR SOUTH BACK
NORTH AS A WARM FRONT. CONVERGENCE OVER THE OLD FRONTAL BOUNDARY IN
ADDITION TO INCREASING UPSLOPE WIND FLOW ON THE SOUTHEAST SIDE OF
THE APPALACHIANS WILL RESULT IN THE DEVELOPMENT OF RAIN/DRIZZLE
ACROSS THE AREA TUESDAY NIGHT...INCREASING IN INTENSITY TOWARD
DAYBREAK WEDNESDAY. BOTH TEMPERATURES AND DEWPOINTS WILL ON THE
RISE TUESDAY NIGHT...THE COOLEST TEMPERATURES OCCURRING BEFORE
MIDNIGHT...THEN STEADILY RISING. RAIN COVERAGE AND INTENSITY WILL
CONTINUE TO INCREASE UNTIL THE PASSAGE OF THE STRONG COLD
FRONT...MID-DAY WEDNESDAY.
TYPICAL WITH THESE SORT OF SYSTEMS...AND ESPECIALLY ON SATURATED
GROUND FROM OUR EXISTING SNOW MELT...CONCERNS OF RAINFALL...WIND...
AND THUNDERSTORMS WOULD BE CONSIDERED. HOWEVER...INDICATIONS ARE
THAT THE MAIN DYNAMICS WILL TRACK WELL NORTH OF THE REGION...THE
SYSTEM MOVING RATHER QUICKLY THROUGH THE REGION...AND INSTABILITY IS
MARGINAL AT BEST. AS A RESULT...QPF SHOULD GENERALLY BE LESS THAN
ONE INCH...AND WHEN COMBINED WITH SNOW MELT SHOULD NOT POSE ANY
SIGNIFICANT RUNOFF PROBLEMS. THAT SAID...A WIND ADVISORY MAY BE
WARRANTED FOR PARTS OF THE FORECAST AREA...BUT DO NOT ANTICIPATE
OTHER HEADLINES ATTM.
THE RAIN IS EXPECTED TO COME TO AN END FROM WEST TO EAST WEDNESDAY
AFTERNOON. IN SPITE OF THE SUBSIDENCE IN THE WAKE OF THE
FRONT...THE EASTWARD PROGRESS OF THE FRONT IS EXPECTED TO SLOW AS IT
ENCOUNTERS AN UPPER RIDGE OFF THE COAST. MODELS ALSO HINT THAT A
WAVE OF LOW PRESSURE WILL FORM ALONG THE FRONT THURSDAY WHICH
WOULD...AT THE VERY LEAST RESULT IN LINGERING CLOUDINESS ACROSS THE
FORECAST AREA.
TEMPERATURES WEDNESDAY WILL SPIKE JUST PRIOR TO FROPA...POSSIBLY
REACHING THE 60S ACROSS THE PIEDMONT. ONCE THE FRONT MOVES
THROUGH...TEMPERATURES WILL THEN TREND COLDER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 407 PM EST SUNDAY...
A TREND TOWARD MUCH COLDER CONDITIONS AND GENERALLY DRY WEATHER
EXPECTED FOR THE WEEKEND. HOWEVER...MODELS STILL SOMEWHAT
TROUBLESOME ABOUT LOW PRESSURE DEVELOPING ALONG THE REMNANT FRONTAL
BOUNDARY/BAROCLINIC ZONE ALONG THE SOUTHEAST U.S. COAST. MODEL
CONSENSUS IS TO KEEP THIS PRECIPITATION SOUTH AND EAST OF OUR REGION
AND THIS PACKAGE CONTINUES TO ADVERTISE A DRY FORECAST FOR THE RNK
CWA IN THE EXTENDED PERIODS. THIS AGREES WITH WPC THINKING ATTM.
THE EASTERN U.S. TROUGH IS DESTINED TO REMAIN IN PLACE INTO THE
WEEKEND AND AT LEAST THE FIRST HALF OF THE FOLLOWING WEEK AS SEVERAL
ALBERTA CLIPPERS TRACK THROUGH THE EASTERN CONUS HELPING TO
REINFORCE AND DEEPEN THE TROUGH. SEVERAL SURGES OF CANADIAN/ARCTIC
AIR ARE PROGGED TO SPREAD SOUTHEAST...THE INTENSITY OF WHICH VARIES
ACCORDING TO WHATEVER MODEL YOU CHOOSE TO LOOK AT. NONETHELESS...A
TREND TOWARD NORMAL AND EVEN BELOW NORMAL TEMPERATURES APPEARS
LIKELY. QUESTION THEN BECOMES WILL THERE BE ANY SHORT WAVE ENERGY
TO ROUND THE BASE OF THE UPPER TROUGH TO SPAWN SOMETHING THAT
WOULD PRODUCE MORE THAN JUST THE TYPICAL UPSLOPE SNOW SHOWERS.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 1150 PM EST SUNDAY...
CLOUDS WILL THICKEN AND LOWER OVERNIGHT IN ADVANCE OF A COLD
FRONT THAT WILL REACH THE APPALACHIANS MONDAY MORNING. HIGH
CONFIDENCE THAT CEILINGS WILL REMAIN VFR THROUGH 06Z/1AM OVER THE
MOUNTAINS AND 09Z/4AM IN THE FOOTHILLS AND PIEDMONT. NAM/GFS/RAP
AND 18Z LOCAL WRF ALL HAVE RAIN REACHING KBLF AND KLWB AROUND
12Z/7AM MONDAY MORNING. CEILINGS WILL BE MVFR FOR MUCH OF THE DAY
ALONG AND WEST OF THE BLUE RIDGE AS THE RAIN ADVANCES SLOWLY EAST
ACROSS THE MOUNTAINS. DURING THE AFTERNOON...KDAN AND KLYH WILL
HAVE A BETTER PROBABILITY OF RAIN AND MVFR CEILINGS. CONFIDENCE IS
MEDIUM TO HIGH ON THE ARRIVAL TIME OF THE RAIN.
LOW LEVEL WIND SHEAR REMAINS IN THE TAFS OVERNIGHT WITH A LOW
LEVEL WSW JET THAT HAS SPEEDS CLOSE TO 50 KNOTS. THE FRONT WILL BE
CLOSE TO THE VIRGINIA/NORTH CAROLINA BORDER BY THE 00Z/7PM END OF
TAF PERIOD.
ONCE THE BOUNDARY CROSSES THROUGH THE AREA AND HIGH PRESSURE
BEGINS THE WEDGE DOWN THE EAST SIDE OF THE APPALACHIANS...RAIN
WILL END BUT CEILINGS WILL REMAIN MVFR TO IFR. LOW CONFIDENCE AS
TO HOW LOW CEILINGS WILL BE AFTER THE FRONT GOES BY.
EXTENDED DISCUSSION...
BY TUESDAY...ABUNDANT LOW LEVEL MOISTURE AND OVERRUNNING WARM AIR
ADVECTION WILL RESULT IN WIDESPREAD IFR TO MVFR CONDITIONS. A
PERIOD OF MODERATE RAIN WILL ARRIVE WITH THE PASSAGE OF A STRONG
FRONT ON WEDNESDAY...AGAIN ALONG WITH IFR/MVFR CEILINGS AND
VISIBILITIES. HIGH PRESSURE WILL RETURN ON THURSDAY...AND PROVIDE
COLDER AIR ALONG WITH A RECOVERY TO VFR CONDITIONS THROUGH FRIDAY.
&&
.EQUIPMENT...
KFCX RADAR IS DOWN UNTIL FURTHER NOTICE. TECHNICIANS WILL
INVESTIGATE EARLY MONDAY MORNING.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PW
NEAR TERM...CF/PW
SHORT TERM...PM
LONG TERM...PM
AVIATION...AMS/PW
EQUIPMENT...CF
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
557 AM CST MON FEB 1 2016
.SHORT TERM...(Today)
ISSUED AT 234 AM CST MON FEB 1 2016
High pressure advancing eastward into Illinois today will bring
cooler air to central Illinois, along with dry conditions. Early
morning temperatures dipping below freezing west and north of Peoria
could create black ice for untreated roads, especially bridges and
overpasses. Satellite images indicate a steady stream of high cirrus
clouds will be present for most of the day today, which should help
to preclude much in the way of thicker fog formation early this
morning. The cooler start and filtered sunshine will produce high
temperatures 10 to 15 degrees cooler than yesterday, but still well
above normal. Highs should reach the mid 40s along and north of
I-74, with lower 50s south of I-70. Winds will be relatively
light today under the surface ridge axis, with wind directions
eventually becoming easterly this afternoon.
.LONG TERM...(Tonight through Sunday)
ISSUED AT 234 AM CST MON FEB 1 2016
Long-advertised winter storm system taking shape across the
southwest U.S. early this morning, with upper low over southern
California and the surface low just east of Las Vegas at 2 am. The
model consensus continues to favor a track across the Oklahoma
panhandle this evening, then northeast across northern Missouri
Tuesday afternoon before reaching the general vicinity of Chicago by
early evening. With us on the south side of the track, the main
concern will be with convective trends, followed by precipitation
trends as the system pulls away Tuesday night.
Have removed the mention of slight chance of freezing rain across
the far northern CWA late tonight, as temperatures appear to stay in
the mid 30s overnight in that area. Forecast soundings do support
some sleet/snow mixing with the rain at first toward Galesburg,
before a quick transition to rain. Rain chances before sunrise will
mainly be west of I-55, as a stiff east wind will slow the column
moistening a bit. However, showers will quickly overspread the
forecast area Tuesday morning. Latest SPC Day2 outlook extended the
marginal risk of severe weather as far northwest as a Bloomington to
Springfield line, with the slight risk as far north as Mattoon and
Paris. Still a significant amount of shear progged in the lower
levels, with 0-6km bulk shear over 80 knots and an 850 mb jet of 60-
65 knots over the eastern CWA this afternoon. With these numbers,
some damaging winds may result with the stronger storms. Have
mentioned a chance of storms over most of the CWA in the afternoon,
but the more organized line will likely be taking shape along the
I-57 corridor around mid afternoon before racing east.
Dry slot continues to be favored by most of the model guidance, with
this feature punching northeast. Several already bring this into the
western CWA by late afternoon, and over most of the CWA in the
evening, and thus the forecast has been trended toward a period of
slight chance/no chance PoP`s in the evening. Overnight, some slight
chances remain warranted through, as the secondary trough axis
swings through. More substantial deformation-type precipitation
generally progged to stay just to our north, but some flurries are
likely to occur into Wednesday morning.
Remainder of the forecast currently expected to remain fairly quiet.
GFS and ECMWF models favor long wave troughs passing through, but
both keep the coldest air bottled up in Canada, so coldest temps on
Wednesday/Thursday still expected to top out in the 30s most areas.
Both favor a more substantial surge of colder air early next week,
beyond the current forecast period.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
ISSUED AT 556 AM CST MON FEB 1 2016
Main concern through the early morning hours will be the threat
for some lower vsbys in fog with the better threat near KPIA in
the 13z-15z time frame. Weak high pressure advancing into central
Illinois is setting up an inversion, trapping low level moisture
near the ground. Satellite images show an area of LIFR clouds and
IFR VIS approaching PIA from the NW. HRRR output indicates it
could reach as far east as PIA between 13z-16z, but confidence is
low on the southern extent of those conditions. Therefore, have
continued to show just MVFR fog in a tempo through 15z and SCT004
clouds. Light MVFR fog has been developing toward CMI and east of
there, but no significant fog is expected near CMI. Otherwise, VFR
conditions should prevail at the terminal sites for a majority of
the next 24 hours.
Winds will remain light and variable under the surface ridge axis
for much of the day. Winds are expected to become easterly late
this afternoon and evening. As the low pressure system approaches
late tonight, easterly surface winds will increase to around 15kt
sustained.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...Geelhart
AVIATION...Shimon
AREA FORECAST DISCUSSION...UPDATED
NWS CARIBOU ME
910 AM EST MON FEB 1 2016
.SYNOPSIS...
LOW PRESSURE WILL PASS TO THE NORTHWEST OF THE STATE TODAY WILL A
COLD FRONT MOVING THROUGH LATE THIS MORNING AND EARLY THIS
AFTERNOON. HIGH PRESSURE WILL BUILD IN TONIGHT AND TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE 900 AM: DROPPED THE FREEZING RAIN ADVISORY AS THE
WIDESPREAD RAIN SHOWERS HAVE LEFT THE AREA AND TEMPERATURES ARE
NOW ABOVE FREEZING ACROSS ALL AREAS...WITH SOLAR INSOLATION
WARMING UP THE ROAD SURFACES. BESIDES THIS TWEAKED POP GRIDS OFF
LATEST HRRR AND NAM FOR POTENTIAL OF RAIN SHOWERS THROUGH MID-DAY
WITH THE COLD FRONT PASSAGE. OVERALL NO SIGNIFICANT WEATHER
EXPECTED TODAY.
UPDATE 5:30 AM: HAVE ADDED FREEZING RAIN ADVIORY FOR NORTH. ALSO
ADJUSTED TEMPERATURE.
LOW PRESSURE IS CURRENTLY PASSING TO THE NORTHWEST OF THE STATE
THIS MORNING. THIS SYSTEM IS EXPECT TO PRODUCE SOME LIGHT RAIN
EARLY THIS MORNING. A COLD FRONT WILL MOVE ACROSS THE REGION LATE
MORNING FOLLOW BY CLEARING BEHIND THE FRONT THIS AFTERNOON. A
COLDER AIR MASS IS THEN EXPECTED TO MOVE IN TONIGHT. HIGH PRESSURE
IS THEN EXPECTED TO APPROACH FROM THE WEST LATE TONIGHT INTO
TUESDAY MORNING.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
THINGS LOOK ON TRACK FOR A WINTER MIX GOING TO RAIN WITH SOME WIND
ON WEDNESDAY.
FIRST THINGS FIRST. 1032MB HIGH PRES IS FORECAST TO MOVE ACROSS
SOUTHERN QUEBEC ON TUESDAY AND THEN SLIDE TO THE E ON TUESDAY
NIGHT. COLDER AIR ASSOCIATED W/THIS HIGH WILL SETTLE ACROSS THE
REGION IN TUESDAY INTO TUESDAY NIGHT. PLENTY OF SUNSHINE EXPECTED
FOR TUESDAY BUT MUCH COLDER THAN THE LAST 4-5 DAYS. DAYTIME
TEMPERATURES ARE EXPECTED BE ABOVE NORMAL W/READINGS IN THE 20S
ACROSS THE NORTHERN 1/2 OF THE REGION TO LOWER 30S CENTRAL AND
DOWNEAST. TUESDAY NIGHT WILL FEATURE CLEAR SKIES FOR THE 1ST 1/2
OF THE NIGHT W/LIGHT WINDS. A DECENT INVERSION LOOKS TO SET UP AND
W/THE COLD AIR DOWN IN THE LLVLS, TEMPERATURES ARE EXPECTED TO
DROP QUICKLY AFTER SUNSET. LIKE THE DAYCREW`S ASSESSMENT OF SINGLE
NUMBERS ACROSS THE NORTH AND WEST W/THE POTENTIAL FOR BELOW ZERO
READINGS ESPECIALLY IN LOW LYING AREAS. CENTRAL AND DOWNEAST WILL
SEE TEMPERATURES DROP INTO THE TEENS AND LOWER 20S. THE OVERNIGHT
LOWS LOOK TO BE HIT EARLY AND THEN GRADUALLY BY EARLY MORNINGWEDNESDAY
DUE TO THICKENING CLOUDS AND SE WINDS PICKING UP.
NOW COMES THE INTERESTING PART. STRONG LOW PRES WHICH DELIVERED A
GOOD DOSE OF SNOW TO THE PLAINS AND PORTIONS OF THE GREAT LAKES IS
FORECAST TO LIFT INTO WESTERN ONTARIO EARLY WEDNESDAY MORNING.
HIGH PRES SLIDES TO THE E W/A SE FLOW AND INCREASING MOISTURE. IT
LOOKS LIKE SNOW WILL BREAK OUT ACROSS FAR W AND SW AREAS AND THEN
SPREAD E BY 7-8AM. SNOW WILL BE SEEN AS FAR S AS THE COAST
INITIALLY, BUT AS THE WARMER AIR WORKS ONTO THE COAST AND DOWNEAST
REGION, A CHANGEOVER TO A BRIEF PERIOD OF SLEET/FREEZING RAIN IS
EXPECTED BEFORE GOING TO ALL RAIN AS TEMPS WARM ABOVE FREEZING.
FURTHER N, IT LOOKS LIKE SNOW THROUGH ABOUT 12PM OR SO AND THEN A
CHANGE TO SLEET/FREEZING RAIN THROUGH THE AFTERNOON. ACROSS THE
ST. JOHN VALLEY, SNOW WILL HANG A BIT LONGER BEFORE GOING OVER TO
FREEZING PRECIP LEADING TO HIGHER SNOW TOTALS. CONFIDENCE IS
BUILDING THAT A MEASURABLE SNOWFALL IS POSSIBLE W/THE EVENT. ATTM,
SNOW ACCUMULATIONS OF 3-5 INCHES ARE EXPECTED FROM CARIBOU AND PRESQUE
ISLE NORTHWARD, FURTHER S TOWARD HOULTON AND MILLINOCKET, 1-3
INCHES W/AN INCH OR LESS ACROSS CENTRAL AND DOWNEAST AREAS. GIVEN
THE POSITION OF THE HIGH AND THE LOW EXPECTED TO MOVE THROUGH
NORTHERN QUEBEC, THE FREEZING PRECIP SHOULD BE SHORT LIVED
W/ACCUMULATIONS LESS THAN 0.10". THIS MATCHES WELL W/A LOCAL STUDY
SHOWING WARMER AIR TO TAKE HOLD QUICKLY AS WINDS TURN TO THE S.
SO, WINTER WEATHER ADVISORIES MIGHT BE NEEDED. SINCE, THE EVENT IS
PRIMARILY IN THE 3RD PERIOD, WILL BEEF UP WORDING IN THE HAZARDOUS
WEATHER OUTLOOK.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
RAIN AND WIND WEDNESDAY NIGHT AT LEAST THROUGH MIDNIGHT AS
SOUTHERLY WINDS TAKE OVER AND STRONG PRES GRADIENT IS IN PLACE.
ONCE AGAIN, FAR NORTHERN AREAS UP NEAR THE CANADIAN-MAINE BORDER
WILL SEE FREEZING PRECIP HANG ON A BIT LONGER INTO THE EARLY
EVENING. ONE THING TO NOTE HERE IS RAIN HITTING THE COLDER ROAD
SURFACES COULD LEAD TO SOME ICING DESPITE THE AIR TEMPERATURES
WARMING INITIALLY. ALL AREAS SHOULD SEE RAIN BY MID EVENING
W/TEMPERATURES PUSHING WELL INTO THE 30S AND 40S. AS A MATTER OF
FACT, THE WARMEST TEMPERATURES WILL BE OCCUR BY MIDNIGHT BEFORE
DROPPING BACK AS THE COLD FRONT SWINGS THROUGH ON THURSDAY.
SOUTHERLY WINDS WILL BE AT THEIR HIGHEST DURING THE EVENING
W/THE STRONGEST SPEEDS EXPECTED ACROSS THE DOWNEAST AND COASTAL
REGION. THE GUIDANCE HAS BEEN BACKING OFF THE STRONG LLVL JET
W/THE LATEST PROJECTIONS SHOWING 50-55 KT FROM 900-850MBS. A NICE
ALIGNMENT IS SHOWN TO SETUP ACROSS THE DOWNEAST AND EASTERN MAINE.
CONFIDENCE IS BUILDING THAT THERE COULD BE POTENTIAL FOR GUSTS TO
HIT NEAR 50 MPH W/THE STRONGER WINDS CAN GET MIXED DOWN. RAINFALL
APPEARS TO BE IN 2 AREAS W/ONE AREA MOVING ACROSS NORTHERN AREAS
AND THEN OTHER HEAVIER BATCH ACROSS DOWNEAST AND ALONG THE COAST.
ATTM, STORM TOTAL QPF OF 0.50 TO 1.00" POSSIBLE. CONFIDENCE ON THE
QPF ATTM IS STILL LOW AS ANY SHIFT COULD AFFECT THE AMOUNTS.
THE COLDER AIR WILL FILTER IN ACROSS THE REGION BY THURSDAY
MORNING AND CONTINUE THROUGH THE DAY ON THURSDAY. TEMPERATURES
HOWEVER ARE EXPECTED TO BE WELL INTO THE 30S WITH SOME CONTINUED
MELTING.
ANOTHER THING TO MENTION IS THE POTENTIAL FOR SOME ICE BREAK UP
ON THE RIVERS DUE TO THE MELTING AND ADDED RUNOFF. SOME RISES ARE
EXPECTED. THIS WILL BE MONITORED AS WE MOVE CLOSER TO THE EVENT.
NW FLOW AND COLDER FRONT CROSSING THE REGION ON THURSDAY W/SOME
SNOW SHOWERS AROUND MAINLY N AND W. A NW BREEZE HANGS ON INTO
THURSDAY NIGHT W/A COLD NIGHT EXPECTED. CLOUDS WILL HANG ON FOR A
TIME ACROSS THE NORTHERN TIER W/TEH FLOW COMING OFF THE ST.
LAWRENCE. FURTHER S, SKIES SHOULD CLEAR. THE WIND WILL KEEP
TEMPERATURES UP INTO THE SINGLE NUMBERS AND LOWER TEENS NORTH AND
WEST W/MID AND UPPER TEENS CENTRAL AND DOWNEAST. REMAINING COLDER
ON FRIDAY W/HIGH PRES MOVING ACROSS THE REGION. THE NEXT WEATHER
SYSTEM IS EXPECTED TO MOVE ACROSS THE REGION LATER NEXT WEEKEND
W/THE POTENTIAL FOR SOME SNOW. TEMPERATURES DURING THIS TIMEFRAME
ARE EXPECTED TO STAY ABOVE NORMAL.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
NEAR TERM: MVFR CONDITIONS ARE EXPECTED THIS MORNING FOLLOW BY VFR
CONDITIONS LATER THIS AFTERNOON AND TONIGHT.
SHORT TERM: VFR TUESDAY INTO TUESDAY NIGHT FOR ALL TERMINALS. MVFR
TO IFR FOR WEDNESDAY INTO WEDNESDAY EVENING. SNOW GOING TO
FREEZING RAIN/SLEET AND THEN RAIN BY WEDNESDAY EVENING. THIS WILL
LEAD TO SOME ICING CONCERNS. STRONG S WINDS WILL LEAD TO LLWS.
IMPROVEMENT EXPECTED ON THURSDAY FOR KBGR AND KBHB TO MVFR WHILE
NORTHERN TERMINALS WILL SEE MVFR W/SNOW SHOWERS POSSIBLE.
&&
.MARINE...
NEAR TERM: HAVE USED THE NAM12 FOR SUSTAINED WINDS. FOR WAVES:
SOUTHERLY WIND WAVE IN A FETCH ACROSS THE GULF OF MAINE IS
EXPECTED TO BE THE DOMINATE WAVE SYSTEM (8-9 FEET/9 SECONDS)
THROUGH THIS AFTERNOON. FOR TONIGHT WINDS WILL BECOME OFF-SHORE
BEHIND THE COLD FRONT. THE PRIMARY WAVE SYSTEM TONIGHT WILL
CONTINUE TO BE THE SOUTHERLY WAVE SYSTEM IN THE GULF OF MAINE
ACCOMPANIED BY THE SECONDARY OFF-SHORE WIND WAVE. FOR WAVE HEIGHTS
WILL USE THE NEAR SHORE WAVE MODEL.
SHORT TERM: SCA CONDITIONS EARLY TUESDAY WILL DROP OFF BY MIDDAY.
A RETURN TO SCA COMES ON WEDNESDAY W/POTENTIAL FOR GALE FORCE
WINDS BY WEDNESDAY NIGHT AS A STRONG LLVL JET MOVES ACROSS THE
WATERS. S WINDS ARE FORECAST TO INCREASE TO 25-35 KTS W/GUSTS
APPROACHING 40 KTS FOR THE OUTER ZONES. THE WINDS WILL VEER TO THE
NW BY THURSDAY W/15-20 KTS POSSIBLE. WAVE HEIGHTS ARE EXPECTED TO
BUILD WEDNESDAY INTO WEDNESDAY TO 9 TO 14 FEET. A SURGE IS
POSSIBLE ALONG THE COAST LATER WEDNESDAY INTO WEDNESDAY NIGHT, BUT
ATTM THIS TIME, NO COASTAL FLOODING IS EXPECTED. THIS WILL BE
MONITORED AS WE CLOSE INTO THE EVENT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...MIGNONE/DUMONT
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...MIGNONE/DUMONT/HEWITT
MARINE...MIGNONE/DUMONT/HEWITT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
747 AM EST MON FEB 1 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EST MON FEB 1 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW ACROSS THE
CONUS. A POTENT LOOKING SRN STREAM SHORTWAVE IS MOVING ACROSS SRN
CA/SRN NV INTO AZ. THIS WAVE WILL QUICKLY MOVE E THEN NE...BRINGING
A WINTER STORM TO THE UPPER GREAT LAKES TUE AFTN THRU WED MORNING.
IN THE MEANTIME...THE UPPER LAKES ARE CURRENTLY UNDER BENIGN
CONFLUENT WESTERLY FLOW BTWN A TROF OVER CANADA ANCHORED BY MID
LEVEL LOW IN THE VCNTY OF HUDSON BAY AND SRN STREAM RIDGING OVER THE
SE STATES. WEAK SHORTWAVE AND A SFC TROF DROPPING S ACROSS LAKE
SUPERIOR INTO NRN UPPER MI HAS GENERATED SOME -SN OVERNIGHT ACROSS
PARTS OF THE NRN FCST AREA.
THE TODAY/TONIGHT PERIOD WILL GENERALLY BE QUIET. 850MB TEMPS WILL
GRADUALLY FALL TO MARGINAL LEVELS FOR LES OVER MAINLY CNTRL AND ERN
LAKE SUPERIOR. WITH SFC TROF THAT IS AIDING THE ONGOING PATCHY -SN
MOVING S AND GRADUALLY DISSIPATING...THERE MAY NOT BE MUCH TO
GENERATE -SHSN GIVEN THE MARGINAL AT BEST OVERWATER INSTABILITY. IN
ADDITION...THERE IS SOME CONCERN THAT A LITTLE -FZDZ COULD OCCUR
WITH MOISTURE DEPTH AT TIMES NOT REACHING THE -10C ISOTHERM...BUT
NOT SO SURE THERE WILL BE SUFFICIENT NEAR SATURATION AT THE LOWEST
LEVELS TO SUPPORT -FZDZ AS FCST SOUNDINGS SHOW A DECREASE IN RH BLO
1KFT. AT THIS POINT...AFTER SOME CHC POPS NEAR LAKE SUPERIOR EARLY
THIS MORNING...WILL HAVE NOTHING MORE THAN SCHC POPS FOR -SHSN THRU
THE AFTN. WINDS TEND TO SHIFT OFFSHORE TONIGHT...EXCEPT OVER THE
KEWEENAW. SO...OTHER THAN THE KEWEENAW...WILL GRADUALLY DROP SCHC
POPS TONIGHT. EXPECT MAX TEMPS TODAY MOSTLY IN THE UPPER 20S TO LWR
30S. LOWS TONIGHT WILL BE IN THE MID TEENS TO MID 20S. HOWEVER...
THERE IS SOME POTENTIAL THAT CLOUDS COULD CLEAR OUT FOR A WHILE IN
THE INTERIOR AS BIAS CORRECTED CANADIAN MODELS SHOW MINS DOWN INTO
THE SINGLE DIGITS ACROSS THE INTERIOR W HALF.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 746 AM EST MON FEB 1 2016
GENERAL SYNOPTIC...PHASING OF UPPER WAVES WILL CONTINUE TO
STRENGTHEN ROBUST SYSTEM APPROACHING THE FOUR CORNERS REGION RIGHT
NOW. EXPECT THE RESULT TO BE A MID 990S MB SFC LOW TO MOVE FROM NRN
IL AT 00Z WED TO NRN OR AT LEAST CENTRAL LOWER MI BY 12Z WED.
ALOFT...A CLOSED LOW WILL TRANSITION TO AN OPEN WAVE AS IT
ACCOMPANIES THE SFC LOW THROUGH THE REGION.
UNCERTAINTY...SIMILAR MODEL VARIABILITY TO WHAT WE WERE LOOKING AT
24 HOURS AGO...RELATIVELY SMALL DIFFERENCES IN TRACK AND TIMING
BETWEEN THE BULK OF GUIDANCE. THE MOST NOTABLE VARIANCE FROM THE
CONSENSUS IS THE NAM WHICH IS WEAKER AND FASTER WITH THE
SYSTEM...RESULTING IN SOMEWHAT LOWER SNOW TOTALS...ESPECIALLY OVER
NWRN UPPER MI. HOWEVER...THE NAM HAS BEEN STEADILY TRENDING TOWARD
THE MODEL CONSENSUS...AND CONTINUES TO DO SO WITH THE 06Z/01 RUN.
OTHERWISE...THE GFS AND ECMWF HAVE SHOWN A VERY SIMILAR TRACK FOR
THE LAST COUPLE OF DAYS. UNFORTUNATELY...WITH HOW FAST THIS SYSTEM
IS MOVING...THE CYCLONE DOES NOT REACH MATURE STAGE UNTIL IT KICKS
OUT E OF THE ROCKIES WED NIGHT...SO MODEL GUIDANCE WILL PROBABLY
CONTINUE TO BE SOMEWHAT VARIABLE UNTIL THEN. THAT BEING
SAID...PRETTY CONFIDENT IN SNOWFALL AMOUNTS REACHING WARNING
CRITERIA IN AREAS WHERE WATCHES WERE ISSUED TODAY. SREF MEAN AND
ENSEMBLE MEMBERS ALSO BACK THIS UP WITH GOOD CLUSTERING AND NO
MEMBERS THAT HAVE DRAMATICALLY LOW TOTALS.
SNOW AMOUNTS AND TIMING...EXPECT ALL PRECIP TO BE SNOW...ALTHOUGH
THERE IS AN OUTSIDE CHANCE OF A COUPLE OF HOURS OF FREEZING DRIZZLE
NEAR LAKE MI AS THE DRY SLOT MOVES THROUGH...BUT THAT WOULD BE
IMMEDIATELY AFTER THE SNOW FALLS SO ACCUMULATION ON ROADS WOULD NOT
BE AN ISSUE. CURRENT GUIDANCE SUGGESTS SNOW MOVES INTO THE MENOMINEE
AREA AROUND 18Z TUE AND MOVE N TO TO THE IRONWOOD-BARAGA-MARQUETTE-
NEWBERRY AREA BY SHORTLY AFTER 21Z...THEN COVERING THE REST OF THE
AREA BEFORE 00Z WED. SNOW WILL QUICKLY BECOME HEAVY AFTER IT
INITIATES...WITH THE HEAVIEST SNOW AND MOST OF THE SNOW FALLING
BEFORE MIDNIGHT-1AM TUE NIGHT IN MOST PLACES...HEAVY SNOW POTENTIAL
LASTING LONGER NEAR CENTRAL/ERN LAKE SUPERIOR. IN GENERAL HAVE 6-10
INCHES OVER THE CENTRAL AND E (UPGRADED THOSE AREAS TO WARNING) AND
UP TO 6 INCHES OVER THE W (ADVISORY). WITH MODELS COMING INTO BETTER
ALIGNMENT...POTENTIAL FOR HIGHER AMOUNTS (POSSIBLY MUCH HIGH) ARE
GOING TO HAVE TO BE FINE TUNED. FOR EXAMPLE THE LATE NAM-DNG RUN
PAINTS SIGNIFICANT HIGHER SNOWFALL OVER THE HIGHER TERRAIN OF THE
NCENTRAL. THAT IS VERY TRACK DEPENDENT...BUT THE POTENTIAL IS THERE.
SEE THE WSW FOR MORE DETAILS ON SNOWFALL AMOUNTS AND OTHER
ASSOCIATED HAZARDS (BLOWING SNOW).
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 653 AM EST MON FEB 1 2016
IN THE WAKE OF A LOW PRES TROUGH THAT HAS DROPPED INTO UPPER MI...
LOW LEVEL MOISTURE AIDED BY FLOW OFF LAKE SUPERIOR SHOULD LEAD TO
PREVAILING MVFR CIGS AT KIWD/KCMX/KSAW THRU THE FCST PERIOD. THERE
COULD BE SOME FLURRIES OR EVEN -FZDZ...ESPECIALLY AT KSAW THIS
MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 507 AM EST MON FEB 1 2016
THE TUE NIGHT/WED TIME FRAME WILL BE THE MAIN PERIOD OF INTEREST FOR
STRONG WINDS ON LAKE SUPERIOR THIS WEEK AS LOW PRES TRACKS FROM THE
SRN PLAINS ACROSS FAR NORTHERN LWR MI. LOOKS LIKE THE LOW WILL
GENERATE A PERIOD OF NE TO N GALE FORCE WIND GUSTS LATE TUE NIGHT
THRU EARLY WED AFTN OVER ALL BUT FAR WRN LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING FROM 4 PM TUESDAY TO 4 PM EST WEDNESDAY FOR
MIZ004>007-085.
WINTER WEATHER ADVISORY FROM 4 PM EST /3 PM CST/ TUESDAY TO 7 AM
EST /6 AM CST/ WEDNESDAY FOR MIZ001>003-009-084.
WINTER STORM WARNING FROM 4 PM TUESDAY TO 1 PM EST WEDNESDAY FOR
MIZ013-014.
WINTER STORM WARNING FROM NOON TUESDAY TO 6 AM CST WEDNESDAY FOR
MIZ012.
WINTER STORM WARNING FROM 3 PM TUESDAY TO 6 AM CST WEDNESDAY FOR
MIZ010-011.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
654 AM EST MON FEB 1 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EST MON FEB 1 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW ACROSS THE
CONUS. A POTENT LOOKING SRN STREAM SHORTWAVE IS MOVING ACROSS SRN
CA/SRN NV INTO AZ. THIS WAVE WILL QUICKLY MOVE E THEN NE...BRINGING
A WINTER STORM TO THE UPPER GREAT LAKES TUE AFTN THRU WED MORNING.
IN THE MEANTIME...THE UPPER LAKES ARE CURRENTLY UNDER BENIGN
CONFLUENT WESTERLY FLOW BTWN A TROF OVER CANADA ANCHORED BY MID
LEVEL LOW IN THE VCNTY OF HUDSON BAY AND SRN STREAM RIDGING OVER THE
SE STATES. WEAK SHORTWAVE AND A SFC TROF DROPPING S ACROSS LAKE
SUPERIOR INTO NRN UPPER MI HAS GENERATED SOME -SN OVERNIGHT ACROSS
PARTS OF THE NRN FCST AREA.
THE TODAY/TONIGHT PERIOD WILL GENERALLY BE QUIET. 850MB TEMPS WILL
GRADUALLY FALL TO MARGINAL LEVELS FOR LES OVER MAINLY CNTRL AND ERN
LAKE SUPERIOR. WITH SFC TROF THAT IS AIDING THE ONGOING PATCHY -SN
MOVING S AND GRADUALLY DISSIPATING...THERE MAY NOT BE MUCH TO
GENERATE -SHSN GIVEN THE MARGINAL AT BEST OVERWATER INSTABILITY. IN
ADDITION...THERE IS SOME CONCERN THAT A LITTLE -FZDZ COULD OCCUR
WITH MOISTURE DEPTH AT TIMES NOT REACHING THE -10C ISOTHERM...BUT
NOT SO SURE THERE WILL BE SUFFICIENT NEAR SATURATION AT THE LOWEST
LEVELS TO SUPPORT -FZDZ AS FCST SOUNDINGS SHOW A DECREASE IN RH BLO
1KFT. AT THIS POINT...AFTER SOME CHC POPS NEAR LAKE SUPERIOR EARLY
THIS MORNING...WILL HAVE NOTHING MORE THAN SCHC POPS FOR -SHSN THRU
THE AFTN. WINDS TEND TO SHIFT OFFSHORE TONIGHT...EXCEPT OVER THE
KEWEENAW. SO...OTHER THAN THE KEWEENAW...WILL GRADUALLY DROP SCHC
POPS TONIGHT. EXPECT MAX TEMPS TODAY MOSTLY IN THE UPPER 20S TO LWR
30S. LOWS TONIGHT WILL BE IN THE MID TEENS TO MID 20S. HOWEVER...
THERE IS SOME POTENTIAL THAT CLOUDS COULD CLEAR OUT FOR A WHILE IN
THE INTERIOR AS BIAS CORRECTED CANADIAN MODELS SHOW MINS DOWN INTO
THE SINGLE DIGITS ACROSS THE INTERIOR W HALF.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 514 PM EST SUN JAN 31 2016
A BROAD MID/UPPER LEVEL TROUGH OVER THE WEST INTO CNTRL CONUS WILL
GIVE WAY TO RIDGING OVER WRN NOAM RESULTING IN NW FLOW INTO THE NRN
LAKES AND INTRUSIONS OF ARCTIC AIR INTO OR JUST TO THE NE OF THE
REGION. THE MAIN WEATHER STORY WILL BE THE WINTER STORM MOVING OUT
OF THE PLAINS INTO THE GREAT LAKES TUE INTO WED.
MONDAY NIGHT...WEAK LOW LEVEL FLOW WILL PREVAIL WITH SFC RIDGING
FROM SASK/MANITOBA THROUGH THE NRN LAKES. WNW 925-850 MB FLOW WITH
850 MB TEMPS AROUND -11C WILL SUPPORT POTENTIAL FOR SOME LIGHT LES.
TUESDAY INTO WEDNESDAY...THE MODELS WERE IN RELATIVELY GOOD
AGREEMENT WITH THE EVOLUTION OF THE WINTER STORM EMERGING FROM THE
PLAINS WITH LITTLE CHANGE FROM PREVIOUS FCSTS. ALTHOUGH THE GFS
REMAINED A BIT FARTHER N WITH THE PATH...OVERALL DIFFERENCES
COMPARED TO THE ECMWF/GEM OR DEPARTURE FROM GFS ENSEMBLE MEAN WAS
RELATIVELY MINOR. HOWEVER...THE MODELS HAVE TRENDED SLIGHTLY FASTER
WITH THE SYSTEM.
AS THE MID LEVEL LOW LIFTS OUT OF THE PLAINS STRONG 700-300 MB
QVECTOR CONV AND 290K-300K ISENTROPIC LIFT WILL SUPPORT A PERIOD OF
HEAVY SNOW...ESPECIALLY FROM 21Z/02-06Z/03. QPF AMOUNTS IN THE 0.4
TO 0.7 INCH RANGE ARE CONSISTENT WITH THE DECENT MOISTURE TRANSPORT
AND 3 G/KG AVAILABLE. EVEN WITH THE STRONGEST LIFT ABOVE THE
DGZ...SLR VALUES IN THE 15/1-20/1 RANGE ARE EXPECTED LEADING TO 12-
18 HOUR SNOWFALL AMOUNTS OF 8 TO 10 INCHES OVER MUCH OF THE CNTRL
CWA...WITH THE HEAVIEST AMOUNTS OVER THE S AND E. SINCE THE WRN CWA
FROM IWD TO CMX WILL BE ON THE WRN SIDE OF THE LARGE SYNOPTIC PCPN
AREA...CONFIDENCE IN REACHING WARNING AMOUNTS WAS LOWER.
ACCORDINGLY...THE POTENTIAL FOR LAKE ENHANCEMENT OVER THE WEST IS
ALSO LOWER...ESPECIALLY DURING THE PORTION OF THE EVENT WITH NE LOW
LEVEL FLOW. SO...THE WINTER STORM WATCH WAS ISSUED FOR BARAGA/IRON
COUNTIES EASTWARD. LAKE AND UPSLOPE FLOW ENHANCEMENT WILL BE LIKELY
INTO N CNTRL UPPER MI AS 850 MB TEMPS FALL TO AROUND -10C BY 06Z/WED
WITH INCREASING NNE WINDS. SNOW TOTALS MAY EXCEED 12 INCHES IN THE
HIGHER TERRAIN WEST OF MARQUETTE. THE HEAVIER SNOW IS EXPECTED TO END
OVER THE SOUTH BY 12Z AND IN THE NORTH BY AFTERNOON AS THE SYNOPTIC
MOISTURE/LIFT DEPART BUT WITH THE WINDS...DRIVING WILL STILL BE
DIFFICULT.
ALTHOUGH THE FCST WINDS ARE NOT EXTREMELY STRONG AND SLIGHTLY LOWER
THAN PRREVIOUS FCSTS...CONSIDERABLE BLSN IS EXPECTED NEAR LAKE
SUPERIOR AND S CNTRL FROM ESC-MNM.
THU-SUN...A FEW CLIPPER SHORTWAVE TROUGHS ARE EXPECTED TO MOVE
THROUGH THE NRN LAKES THAT COULD BRING SOME LIGHT SNOW TO THE CWA.
THERE IS LOW CONFIDENCE IN TIMING/POSITION OF THESE FEATURES AND
IMPACT ON LES. COLD ENOUGH AIR WILL PREVAIL FOR PERIODS OF LES FOR
MAINLY NW FLOW FAVORED LOCATIONS. THE GFS WAS MORE AGGRESSIVE IN
BRINING COLD AIR INTO THE NRN LAKES BY NEXT WEEKEND COMPARED TO THE
ECMWF.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 653 AM EST MON FEB 1 2016
IN THE WAKE OF A LOW PRES TROUGH THAT HAS DROPPED INTO UPPER MI...
LOW LEVEL MOISTURE AIDED BY FLOW OFF LAKE SUPERIOR SHOULD LEAD TO
PREVAILING MVFR CIGS AT KIWD/KCMX/KSAW THRU THE FCST PERIOD. THERE
COULD BE SOME FLURRIES OR EVEN -FZDZ...ESPECIALLY AT KSAW THIS
MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 507 AM EST MON FEB 1 2016
THE TUE NIGHT/WED TIME FRAME WILL BE THE MAIN PERIOD OF INTEREST FOR
STRONG WINDS ON LAKE SUPERIOR THIS WEEK AS LOW PRES TRACKS FROM THE
SRN PLAINS ACROSS FAR NORTHERN LWR MI. LOOKS LIKE THE LOW WILL
GENERATE A PERIOD OF NE TO N GALE FORCE WIND GUSTS LATE TUE NIGHT
THRU EARLY WED AFTN OVER ALL BUT FAR WRN LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING FROM 4 PM TUESDAY TO 4 PM EST WEDNESDAY FOR
MIZ004>007-085.
WINTER WEATHER ADVISORY FROM 4 PM EST /3 PM CST/ TUESDAY TO 7 AM
EST /6 AM CST/ WEDNESDAY FOR MIZ001>003-009-084.
WINTER STORM WARNING FROM 4 PM TUESDAY TO 1 PM EST WEDNESDAY FOR
MIZ013-014.
WINTER STORM WARNING FROM NOON TUESDAY TO 6 AM CST WEDNESDAY FOR
MIZ012.
WINTER STORM WARNING FROM 3 PM TUESDAY TO 6 AM CST WEDNESDAY FOR
MIZ010-011.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
507 AM EST MON FEB 1 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EST MON FEB 1 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW ACROSS THE
CONUS. A POTENT LOOKING SRN STREAM SHORTWAVE IS MOVING ACROSS SRN
CA/SRN NV INTO AZ. THIS WAVE WILL QUICKLY MOVE E THEN NE...BRINGING
A WINTER STORM TO THE UPPER GREAT LAKES TUE AFTN THRU WED MORNING.
IN THE MEANTIME...THE UPPER LAKES ARE CURRENTLY UNDER BENIGN
CONFLUENT WESTERLY FLOW BTWN A TROF OVER CANADA ANCHORED BY MID
LEVEL LOW IN THE VCNTY OF HUDSON BAY AND SRN STREAM RIDGING OVER THE
SE STATES. WEAK SHORTWAVE AND A SFC TROF DROPPING S ACROSS LAKE
SUPERIOR INTO NRN UPPER MI HAS GENERATED SOME -SN OVERNIGHT ACROSS
PARTS OF THE NRN FCST AREA.
THE TODAY/TONIGHT PERIOD WILL GENERALLY BE QUIET. 850MB TEMPS WILL
GRADUALLY FALL TO MARGINAL LEVELS FOR LES OVER MAINLY CNTRL AND ERN
LAKE SUPERIOR. WITH SFC TROF THAT IS AIDING THE ONGOING PATCHY -SN
MOVING S AND GRADUALLY DISSIPATING...THERE MAY NOT BE MUCH TO
GENERATE -SHSN GIVEN THE MARGINAL AT BEST OVERWATER INSTABILITY. IN
ADDITION...THERE IS SOME CONCERN THAT A LITTLE -FZDZ COULD OCCUR
WITH MOISTURE DEPTH AT TIMES NOT REACHING THE -10C ISOTHERM...BUT
NOT SO SURE THERE WILL BE SUFFICIENT NEAR SATURATION AT THE LOWEST
LEVELS TO SUPPORT -FZDZ AS FCST SOUNDINGS SHOW A DECREASE IN RH BLO
1KFT. AT THIS POINT...AFTER SOME CHC POPS NEAR LAKE SUPERIOR EARLY
THIS MORNING...WILL HAVE NOTHING MORE THAN SCHC POPS FOR -SHSN THRU
THE AFTN. WINDS TEND TO SHIFT OFFSHORE TONIGHT...EXCEPT OVER THE
KEWEENAW. SO...OTHER THAN THE KEWEENAW...WILL GRADUALLY DROP SCHC
POPS TONIGHT. EXPECT MAX TEMPS TODAY MOSTLY IN THE UPPER 20S TO LWR
30S. LOWS TONIGHT WILL BE IN THE MID TEENS TO MID 20S. HOWEVER...
THERE IS SOME POTENTIAL THAT CLOUDS COULD CLEAR OUT FOR A WHILE IN
THE INTERIOR AS BIAS CORRECTED CANADIAN MODELS SHOW MINS DOWN INTO
THE SINGLE DIGITS ACROSS THE INTERIOR W HALF.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 514 PM EST SUN JAN 31 2016
A BROAD MID/UPPER LEVEL TROUGH OVER THE WEST INTO CNTRL CONUS WILL
GIVE WAY TO RIDGING OVER WRN NOAM RESULTING IN NW FLOW INTO THE NRN
LAKES AND INTRUSIONS OF ARCTIC AIR INTO OR JUST TO THE NE OF THE
REGION. THE MAIN WEATHER STORY WILL BE THE WINTER STORM MOVING OUT
OF THE PLAINS INTO THE GREAT LAKES TUE INTO WED.
MONDAY NIGHT...WEAK LOW LEVEL FLOW WILL PREVAIL WITH SFC RIDGING
FROM SASK/MANITOBA THROUGH THE NRN LAKES. WNW 925-850 MB FLOW WITH
850 MB TEMPS AROUND -11C WILL SUPPORT POTENTIAL FOR SOME LIGHT LES.
TUESDAY INTO WEDNESDAY...THE MODELS WERE IN RELATIVELY GOOD
AGREEMENT WITH THE EVOLUTION OF THE WINTER STORM EMERGING FROM THE
PLAINS WITH LITTLE CHANGE FROM PREVIOUS FCSTS. ALTHOUGH THE GFS
REMAINED A BIT FARTHER N WITH THE PATH...OVERALL DIFFERENCES
COMPARED TO THE ECMWF/GEM OR DEPARTURE FROM GFS ENSEMBLE MEAN WAS
RELATIVELY MINOR. HOWEVER...THE MODELS HAVE TRENDED SLIGHTLY FASTER
WITH THE SYSTEM.
AS THE MID LEVEL LOW LIFTS OUT OF THE PLAINS STRONG 700-300 MB
QVECTOR CONV AND 290K-300K ISENTROPIC LIFT WILL SUPPORT A PERIOD OF
HEAVY SNOW...ESPECIALLY FROM 21Z/02-06Z/03. QPF AMOUNTS IN THE 0.4
TO 0.7 INCH RANGE ARE CONSISTENT WITH THE DECENT MOISTURE TRANSPORT
AND 3 G/KG AVAILABLE. EVEN WITH THE STRONGEST LIFT ABOVE THE
DGZ...SLR VALUES IN THE 15/1-20/1 RANGE ARE EXPECTED LEADING TO 12-
18 HOUR SNOWFALL AMOUNTS OF 8 TO 10 INCHES OVER MUCH OF THE CNTRL
CWA...WITH THE HEAVIEST AMOUNTS OVER THE S AND E. SINCE THE WRN CWA
FROM IWD TO CMX WILL BE ON THE WRN SIDE OF THE LARGE SYNOPTIC PCPN
AREA...CONFIDENCE IN REACHING WARNING AMOUNTS WAS LOWER.
ACCORDINGLY...THE POTENTIAL FOR LAKE ENHANCEMENT OVER THE WEST IS
ALSO LOWER...ESPECIALLY DURING THE PORTION OF THE EVENT WITH NE LOW
LEVEL FLOW. SO...THE WINTER STORM WATCH WAS ISSUED FOR BARAGA/IRON
COUNTIES EASTWARD. LAKE AND UPSLOPE FLOW ENHANCEMENT WILL BE LIKELY
INTO N CNTRL UPPER MI AS 850 MB TEMPS FALL TO AROUND -10C BY 06Z/WED
WITH INCREASING NNE WINDS. SNOW TOTALS MAY EXCEED 12 INCHES IN THE
HIGHER TERRAIN WEST OF MARQUETTE. THE HEAVIER SNOW IS EXPECTED TO END
OVER THE SOUTH BY 12Z AND IN THE NORTH BY AFTERNOON AS THE SYNOPTIC
MOISTURE/LIFT DEPART BUT WITH THE WINDS...DRIVING WILL STILL BE
DIFFICULT.
ALTHOUGH THE FCST WINDS ARE NOT EXTREMELY STRONG AND SLIGHTLY LOWER
THAN PRREVIOUS FCSTS...CONSIDERABLE BLSN IS EXPECTED NEAR LAKE
SUPERIOR AND S CNTRL FROM ESC-MNM.
THU-SUN...A FEW CLIPPER SHORTWAVE TROUGHS ARE EXPECTED TO MOVE
THROUGH THE NRN LAKES THAT COULD BRING SOME LIGHT SNOW TO THE CWA.
THERE IS LOW CONFIDENCE IN TIMING/POSITION OF THESE FEATURES AND
IMPACT ON LES. COLD ENOUGH AIR WILL PREVAIL FOR PERIODS OF LES FOR
MAINLY NW FLOW FAVORED LOCATIONS. THE GFS WAS MORE AGGRESSIVE IN
BRINING COLD AIR INTO THE NRN LAKES BY NEXT WEEKEND COMPARED TO THE
ECMWF.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1242 AM EST MON FEB 1 2016
AT CMX...EXPECT MVFR DECK 010-020 TO REMAIN OVERHEAD IN SOME SHAPE
OR FORM THOUGH TODAY WITH NW WINDS AND WEAK COLD AIR ADVECTION AS
TROUGH SLIDES OVER NORTHERN UPPER MICHIGAN. SMALL POTENTIAL FOR SNOW
SHOWERS BUT VSBY SHOULD BE MVFR FOR THE MOST PART.
AT IWD AND SAW...CONDITIONS ARE VFR BUT WILL TREND DOWN TO MVFR
OVERNIGHT INTO TODAY AS INCREASING LOW-LEVEL MOISTURE ARRIVES AS SFC
TROUGH SLIDES ACROSS. COULD BE LIGHT SNOW SHOWERS/FLURRIES AT TIMES
LATE OVERNIGHT INTO TODAY...ESPECIALLY AT IWD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 507 AM EST MON FEB 1 2016
THE TUE NIGHT/WED TIME FRAME WILL BE THE MAIN PERIOD OF INTEREST FOR
STRONG WINDS ON LAKE SUPERIOR THIS WEEK AS LOW PRES TRACKS FROM THE
SRN PLAINS ACROSS FAR NORTHERN LWR MI. LOOKS LIKE THE LOW WILL
GENERATE A PERIOD OF NE TO N GALE FORCE WIND GUSTS LATE TUE NIGHT
THRU EARLY WED AFTN OVER ALL BUT FAR WRN LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING FROM 4 PM TUESDAY TO 4 PM EST WEDNESDAY FOR
MIZ004>007-085.
WINTER WEATHER ADVISORY FROM 4 PM EST /3 PM CST/ TUESDAY TO 7 AM
EST /6 AM CST/ WEDNESDAY FOR MIZ001>003-009-084.
WINTER STORM WARNING FROM 4 PM TUESDAY TO 1 PM EST WEDNESDAY FOR
MIZ013-014.
WINTER STORM WARNING FROM NOON TUESDAY TO 6 AM CST WEDNESDAY FOR
MIZ012.
WINTER STORM WARNING FROM 3 PM TUESDAY TO 6 AM CST WEDNESDAY FOR
MIZ010-011.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...JLA
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
602 AM CST MON FEB 1 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 402 AM CST MON FEB 1 2016
CLEAR SKIES...LIGHT WINDS AND MOIST LOW LEVEL CONDITIONS FROM THE
MELTING ON SUNDAY HAS ALLOWED FOG TO FORM AT MOST LOCATIONS EARLY
THIS MORNING. PATCHY AREAS OF DENSE FOG ARE COMMON ONCE AGAIN THIS
MORNING ACROSS CENTRAL MN AND ALONG HIGHWAY 8 IN WEST CENTRAL WI.
HELPING TO ABATE THE FOG SOME IS AN INCREASE IN LOW CLOUDINESS FROM
NORTHERN AREAS OF THE STATE. THIS MASS OF LOW CEILINGS IS BEING
HANDLED FAIRLY WELL BY THE RAP AND NAM AT 875MB. THIS WOULD BRING
THE CLOUDS SOUTHEAST TODAY ALONG AND NORTH OF THE I-94 CORRIDOR.
HENCE...THE NORTHEAST HALF OF THE CWA WILL SEE THE MOST CLOUDINESS
TODAY WHILE THE SOUTHWEST HALF WILL SEE A GOOD DEAL OF SUNSHINE. IT
WILL BE ANOTHER MILD DAY WITH HIGHS FROM 30 TO 35 DEGREES.
THE MAIN FEATURE TONIGHT IS THE ONSET OF SNOW AHEAD OF THE WINTER
STORM OVER THE SOUTHWESTERN UNITED STATES EARLY THIS MORNING.
CURRENT THINKING IS THAT SNOW WILL OVERSPREAD THE I-90 CORRIDOR IN
THE 09Z-12Z TIME PERIOD WITH CATEGORICAL POPS IN PLACE. SNOW
ACCUMULATION IN THE THAT THREE HOUR WINDOW IS UP TO A HALF INCH. LOW
TEMPERATURES WERE RAISED A LITTLE BIT ACROSS SOUTHERN AREAS OF THE
FA WITH CLOUDINESS INCREASING FASTER WITH LOWS RANGING FROM THE
TEENS IN CENTRAL MN TO THE LOWER AND MIDDLE 20S TO THE SOUTH AND
EAST.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 402 AM CST MON FEB 1 2016
THE MAIN CONCERN IN THE LONG TERM PERIOD IS THE STRONG WINTER STORM
SET TO IMPACT THE UPPER MIDWEST TOMORROW INTO WEDNESDAY. AFTER THE
STORM MOVES THROUGH THE REGION...TEMPERATURES WILL RUN NEAR NORMAL
FOR EARLY FEBRUARY WITH A FEW CLIPPER SYSTEMS BRINGING POPS INTO THE
FORECAST TOWARD THE WEEKEND.
AS FOR THE LATEST INFORMATION ON THE APPROACHING WINTER
STORM...MODEL GUIDANCE CONTINUES TO WAFFLE BACK AND FORTH. THERE
HAD BEEN TWO DISTINCT CAMPS IN TERMS OF THE TRACK OF THE
STORM...WHICH STILL PERSISTED IN THE 00Z PRODUCT SUITE.
THE GFS HAS CONSISTENTLY BEEN ON THE NORTHERN SIDE OF THE VARIOUS
GUIDANCE. THE ECMWF LEANED TO THE NORTHERN ENVELOPE COMPARED TO THE
GEM AND THE NAM WHICH HAD A VERY SOUTHERN SOLUTION. THE 00Z RUN OF
THE NAM CAME IN WITH A SLIGHT NORTHWARD JOG...AS DID THE 06Z RUN.
THE 12Z EC YESTERDAY TOOK THE 0.5" QPF LINE INTO THE TWIN CITIES
METRO...BUT THEN DIALED IT BACK TO CLOSER TO 0.4" WITH THE 00Z RUN.
THE GFS HAS SLIGHTLY MORE QPF THAN THE LATEST EC. A FIRST LOOK AT
WHAT THE HI-RES ARW AND NMM INDICATE CAME IN OVERNIGHT...WITH
STARK DIFFERENCES AMONG THEM AS WELL. WHILE THE NMM INDICATED 0.48"
OF QPF FOR MSP...THE ARW INDICATED JUST 0.08". THE POINT IS...THERE
IS STILL UNCERTAINTY ALONG THE NORTHERN PERIPHERY OF THE HEAVY SNOW
SWATH...THERE WILL BE A TIGHT SNOWFALL GRADIENT AND IT WILL BE VERY
CLOSE TO THE TWIN CITIES METRO AREA. THIS IS WHY THE WATCH PRODUCTS
WERE LEFT IN PLACE FOR NOW. THE 12Z CYCLE OF MODEL GUIDANCE WILL
HOPEFULLY OFFER LESS UNCERTAINTY AND MORE CONFIDENCE TO NAIL DOWN
WHERE ANY WARNINGS NEED TO BE ISSUED. THE TUESDAY AFTERNOON COMMUTE
WILL BE HEAVILY IMPACTED BY THIS STORM.
OVERALL...THIS FORECAST LEANED TOWARD A BLEND OF THE ECMWF AND
GFS...SO SNOW AMOUNTS WERE GENERALLY TWEAKED UPWARD...AND A COUPLE OF
COUNTIES WERE ADDED TO THE WINTER STORM WATCH. AS FOR THE BLIZZARD
WATCH...DECIDED TO HOLD ON TO IT PRIMARILY DUE TO THE GUIDANCE
BACKING OFF SOME ON THE WINDS ACROSS SOUTH CENTRAL MN. ITS STILL
GOING TO BE BREEZY...BUT WE ARE NOT SURE IF BLIZZARD CRITERIA WILL BE
MET AT THIS TIME. THE WINDS LOOK STRONGER IN IOWA...WHICH EXPLAINS
WHY THEY WERE ABLE TO GO AHEAD WITH A BLIZZARD WARNING THERE. COULD
HAVE GONE WINTER STORM WARNING IN SOUTH CENTRAL MN...BUT DIDNT WANT
PEOPLE TO TAKE THEIR GUARD DOWN ABOUT THE POSSIBILITY OF TRUE
BLIZZARD LIKE CONDITIONS IN SOUTH CENTRAL MN. IF THE 12Z GUIDANCE
COMES IN WITH A SLIGHTLY DEEPER SURFACE LOW...TRUE BLIZZARD
CONDITIONS COULD BE REALIZED. REGARDLESS...TRAVEL ALONG THE I-90
CORRIDOR WILL BE TREACHEROUS TOMORROW WITH HEAVY SNOW AND THE
POTENTIAL FOR 6 TO 10 INCHES.
NOT MUCH IN TERMS OF PRECIPITATION IS EXPECTED BEYOND
TOMORROW...WITH TWO WAVES WORKING SOUTHEAST THROUGH CANADA THROUGH
THE END OF THE WEEK...BUT WOULD PRODUCE VERY LIGHT AMOUNTS OF SNOW.
OTHERWISE...SEASONABLE TEMPERATURES ARE EXPECTED...BUT THE ECMWF
DOES INDICATE THE ARCTIC AIR POURING SOUTH INTO OUR REGION EARLY
NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 602 AM CST MON FEB 1 2016
SADDLED AGAIN EARLY THIS MORNING WITH VARYING CEILINGS AND
VISIBILITIES DUE TO STRATUS AND FOG. AT THIS POINT THE WORST IS
CONFINED TO AREAS ALONG AND NORTH OF I-94. THE AREA OF LOW
MVFR/IFR CEILINGS STRETCH FROM CENTRAL MN ALL THE WAY NORTH TO THE
CANADIAN BORDER. THESE WILL BE SLIDING SE TODAY WITH SOME
IMPROVEMENT EXPECTED IN THE LATE AFTERNOON/EVENING. THIS WILL ONCE
AGAIN LEAVE US VULNERABLE TONIGHT FOR MORE LOW CEILING/VSBY
DEVELOPMENT AS VERY MOIST LOW LEVEL CONDITIONS PERSIST. SNOW WILL
ALSO LIKELY OVERSPREAD FAR SOUTHERN MN BY 12Z TUE. THE SNOW WILL
LIKELY REACH MSP BEFORE THE END OF THE 30 HOUR TAF AT 18Z. LIGHT
WNW WINDS TODAY BECOMING NE TONIGHT.
KMSP...LOW MVFR CEILINGS EXPECTED BY 15Z. THESE COULD COME IN
UNDER 010 AND PERSIST FOR A FEW HOURS WITH A RETURN TO VFR FOR THE
AFTERNOON. INCREASING MID/HIGH LEVEL CLOUDS TONIGHT SHOULD
PRECLUDE ANY BR/FG DEVELOPMENT EARLY TUESDAY MORNING.
HOWEVER...SNOW FROM THE WINTER STORM...CURRENTLY IN THE
SOUTHWESTERN UNITED STATES...WILL LIKELY ARRIVE IN THE 16Z-18Z
TIME FRAME ON TUESDAY WITH A RAPID DETERIORATION FOR THE AFTERNOON
AND EVENING HOURS. SNOW ACCUMULATION TUESDAY AFTERNOON WILL BE
AROUND 3 INCHES WITH AN ADDITIONAL INCH OR TWO TUESDAY EVENING.
/OUTLOOK FOR KMSP/
TUE AFTN...IFR IN SN LIKELY WITH CHC LIFR. WIND NE 10-20 KTS.
TUE NIGHT...IFR IN SN LIKELY WITH CHC LIFR. WIND N 20G35KT.
WED...VFR. WIND NW 15G25KT.
THU...VFR. CHC MVFR IN -SN. SW WIND BCMG WNW 5-10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WATCH FROM TUESDAY MORNING THROUGH LATE TUESDAY
NIGHT FOR WIZ016-024>028.
MN...BLIZZARD WATCH FROM TUESDAY MORNING THROUGH LATE TUESDAY NIGHT
FOR MNZ082>085-091>093.
WINTER STORM WATCH FROM TUESDAY MORNING THROUGH LATE TUESDAY
NIGHT FOR MNZ070-074>078.
&&
$$
SHORT TERM...RAH
LONG TERM...SPD
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
546 AM EST MON FEB 1 2016
.SYNOPSIS...
COLD FRONT PASSES TODAY BUT MILD AGAIN TUESDAY. STRONG SYSTEM MID
WEEK. A RETURN TO COLDER WEATHER FOLLOWS THAT SYSTEM TO END THE
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
COLD FRONT...CURRENTLY ALONG A LINE FROM ROUGHLY CKB TO
HTS...WILL MOVE THROUGH REST OF CWA TODAY...AND HAVE LIKELY POPS
WITH IT. PROGRESSION OF THE FRONT WILL SLOW TO A CRAWL THIS
EVENING ACROSS THE SOUTHERN MOUNTAINS AND COAL FIELDS...BUT DOES
LOOK TO PUSH ALL THE WAY THROUGH THE FORECAST AREA BY AROUND
MIDNIGHT...STALLING SOMEWHERE JUST SOUTH OF THE CWA.
USING A MIX OF THE HRRR AND LAMP...HAVE NON-DIURNAL TEMPERATURE
TRACE FOR TODAY...WITH GRADUALLY FALLING TEMPS BEHIND THE COLD
FRONT. MAY GET A BRIEF UPWARD BOUNCE IN SE OHIO LATE THIS
AFTERNOON IF THE CLOUDS CAN BREAK UP ENOUGH FOR SOME SUN.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
A WARM FRONT PUSHES NORTHWARD THROUGH THE AREA ON TUESDAY WITH
SOUTHERLY WINDS INCREASING. DUE TO RECENT MOS PERFORMANCE IN
SOUTHERLY WINDS...SIDED WITH THE WARMER GFS MOS.
MODELS THEN SHOW SHOWERS AND A COLD FRONT TUESDAY NIGHT INTO
WEDNESDAY. SOUNDINGS AND MOS GUIDANCE INDICATE THAT THUNDERSTORMS
ARE A POSSIBILITY. OF CONCERN IS A STRONG LOW LEVEL JET THAT
OVERLAPS THE INITIAL PRECIPITATION BAND. WORKING AGAINST THE WINDS
GETTING TO THE GROUND HOWEVER...ARE MODEL SOUNDINGS THAT SHOW AN
INVERSION. WILL NEED TO CONTINUE TO MONITOR THIS SITUATION
CLOSELY.
GFS AND ECMWF ARE THEN SHOWING 850 MB TEMPERATURES GETTING COLD
ENOUGH TO OVERTURN THE LOWER LEVELS AND POSSIBLY PRODUCE SOME LIGHT
SNOW OR FLURRIES FOR WEDNESDAY NIGHT INTO THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
ANY RESIDUAL WRAP AROUND RAIN SHOWERS IN THE WAKE OF A COLD FRONT
AND LARGE LOW PRESSURE SYSTEM SPEEDING NEWD AWAY FROM THE
AREA...WILL QUIT OVER THE LOWLANDS AND SWITCH TO UPSLOPE SNOW
SHOWERS OVER THE MOUNTAINS WED EVENING...AND THEN QUIT OVER THE
MOUNTAINS BY THU MORNING...AS LOW LEVEL NW FLOW BECOMES LIGHT
ANTICYCLONIC AHEAD OF HIGH PRESSURE APPROACHING FROM THE W.
THE HIGH MOVES ACROSS THE AREA FOR DRY...SEASONABLY CHILLY
WEATHER THU-SAT. THU DOES NOT LOOK TO PROMISE TOO MUCH
SUNSHINE...THOUGH...GIVEN LINGERING LOW LEVEL MOISTURE YIELDING
STRATOCU...AND HIGH CLOUD ASSOCIATED WITH A WAVE MOVING UP ALONG
THE FRONT THROUGH THE CAROLINAS.
MODELS ARE IN BETTER AGREEMENT ON THE NEXT COLD FRONT CROSSING THE
AREA ON SUNDAY...WITH ANY RAIN SHOWERS AHEAD OF IT SAT NT GOING TO
SOME SNOW SHOWERS OVERNIGHT AS THE FRONT CROSSES...A FEW SNOW
SHOWERS LINGERING ON SUNDAY IN ITS WAKE. THAT SAID...THE FRONT
LOOKS BARELY DISCERNIBLE IN THE ECMWF DEPICTION...AND THE MASS
FIELDS AS A WHOLE DIVERGE BY THEN. THIS LEADS TO UNCERTAINTY AS TO
THE TIMING OF THE NEXT SYSTEM APPROACHING AS EARLY AS THE END OF
DAY 7N NT...
WITH MODEL AGREEMENT THROUGH DAY 6...WPC GUIDANCE AND A BLEND OF
MODEL GUIDANCE WAS EMPLOYED FOR TEMPERATURES...NOT QUITE AS COLD
IN THE WAKE OF THE MID WEEK SYSTEM. LEANED MORE TOWARD THE COLDER GFS
DAY 7.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
BUT AS A COLD FRONT APPROACHES AND SLIDES THROUGH...EXPECT MVFR
CEILINGS AND VISIBILITIES IN SHOWERS. ALSO HAVE A GOOD DOSE OF IFR
IN THE MOUNTAINS INTO THIS AFTERNOON. THIS DOES INCLUDE BKW.
CLOUDS WILL TRY TO BREAK UP LATE IN THE TAF PERIOD...BUT THIS
MAY LEAD TO DENSE FOG ACROSS AT LEAST THE EASTERN HALF OF
CWA. WINDS MAY REMAIN JUST STRONG ENOUGH TO KEEP FOG AT BAY...OR
CLOUDS MAY HANG TOUGH TO LOW CONFIDENCE ON FOG FOR TONIGHT.
SOUTHERLY WINDS AHEAD OF THE FRONT. WINDS WILL THEN SHIFT TO
WESTERLY THEN NORTHERLY AS THE COLD FRONT PROGRESSES ACROSS THE
FORECAST AREA.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z TUESDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF FRONT AND SUBSEQUENT MVFR
CONDITIONS MAY VARY A BIT. FOG MAY NOT BE AN ISSUE EARLY TUESDAY
MORNING...OR COULD BE MORE STRATUS THAN FOG.
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 MON 02/01/16
UTC 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
EST 1HRLY 05 06 07 08 09 10 11 12 13 14 15 16
CRW CONSISTENCY M L M M M L M M M M M M
HTS CONSISTENCY M L M M M M M M M M M M
BKW CONSISTENCY M M L L L L L L L L L M
EKN CONSISTENCY M M M M M M M M M M M M
PKB CONSISTENCY M M M H H H H H M M M M
CKB CONSISTENCY H M M M M M M M M M M M
AFTER 12Z TUESDAY...
IFR POSSIBLE IN SHOWERS TUESDAY NIGHT INTO WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY/MZ
NEAR TERM...MZ
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
741 AM EST MON FEB 1 2016
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS MORNING.
LOW PRESSURE WILL TRACK WEST OF PENNSYLVANIA DURING THE MIDDLE OF
THE WEEK...PUSHING A TRAILING COLD FRONT THROUGH THE AREA LATE
WEDNESDAY. HIGH PRESSURE WILL BUILD OVER THE REGION LATE NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SLOWLY EASTWARD MOVING AND DWINDLING AREA OF SHOWERS WAS NOTED ON
REGIONAL 88D MOSAIC LOOP AT 10Z...ALONG AND AHEAD OF A COLD FRONT
THAT EXTENDED FROM NEAR KBFD TO KPIT.
08Z HRRR /SIMILAR TO THE PAST SEVERAL RUNS/ SHOWS THE SHOWERS
DISSIPATING TO PRACTICALLY NOTHING AS THEY HEAD OFF THE ALLEGHENY
PLATEAU...AND INTO THE CENTRAL RIDGE AND VALLEY REGION OF THE
STATE...WHERE IN THE ABSENCE OF SIGNIFICANT FORCING...THE
PRE AND POST FRONT SWRLY TO WNWRLY LLVL FLOW WILL HAVE A DECIDED
AND MODERATELY STRONG DOWNSLOPE/DRYING COMPONENT.
THE SHOWERS ARE SEEN TO REFORM ACROSS OUR FAR SE ZONES FOR A FEW
HOURS BETWEEN ABOUT 18-20Z TODAY BEFORE SHIFTING EAST TOWARD THE
NEW JERSEY COAST.
IT WILL START OFF CLOUDY TODAY WITH A CORRIDOR OF ISOLATED-SCT
/AND DIMINISHING/ SHOWERS WORKING FROM THE CENTRAL MTNS TOWARD
THE LOWER SUSQ VALLEY ALONG THE AFOREMENTIONED COLD FRONT.
OTHERWISE...THE PM HOURS SHOULD BE DRY WITH GRADUALLY BRIGHTENING
SKIES ACROSS MUCH OF CENTRAL AND NWRN PENN...AS DRIER AIR AND
HIGH PRESSURE BUILD INTO THE AREA.
TEMPS WEIGHTED ABOUT 75 PERCENT TWD NEW CONSENSUS BLENDED MODEL
GUIDANCE YIELD HIGHS IN THE 40S TODAY /SEVERAL DEG OR MORE COOLER
THAN SUNDAY IN MOST LOCATIONS/ EVEN GIVEN THE COOLER READINGS...
HE HIGH TEMPS WILL STILL AVERAGE SOME 5-10 DEG WARMER THAN NORMAL
FOR THE FIRST DAY OF FEBRUARY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
HIGH PRESSURE RIDGE WILL SLIDE EAST ACROSS THE STATE TONIGHT INTO
TUESDAY...BRINGING FAIR WEATHER WITH A LIGHT NORTHWEST-NE
BREEZE. EXPECT JUST SOME SCATTERED ALTO CU AND CIRRUS CLOUDS
SPREADING OVER THE RIDGE TONIGHT AND TUESDAY MORNING. LOW TEMPS
WILL RANGE FROM 25-30F /;WHICH IS ABOUT 5-10F WARMER THAN NORMAL
ACROSS THE CENTRAL AND EASTERN VALLEY LOCATIONS...AND ABOUT 15 DEG
F ABOVE NORMAL ACROSS THE WESTERN MTNS.
THE SOUTHEAST TO SOUTHERLY LLVL FLOW WILL STRENGTHEN LATER TUESDAY
AND TUESDAY NIGHT...AND WILL HELP TO ADVECT THICKENING MULTI-
LAYERED CLOUDS ACROSS THE REGION.
LATEST BLENDED MULTI-MODEL GUIDANCE AND THE TIMING OF THE HIGH`S
DEPARTURE OFF THE MID ATLANTIC AND NEW ENGLAND COASTS TUESDAY AND
INCREASING AFTERNOON CLOUDS SHOULD YIELD A HIGH TEMP IN THE
40S...TO NEAR 50F ACROSS SOME OF THE HIGHER TERRAIN OF THE SOUTH
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
EXPANSIVE ZONAL FLOW PATTERN...COMBINING THE NORTHERN AND
SOUTHERN STREAMS OF THE MAIN JET...STRETCHES FROM COAST TO COAST
THIS WEEKEND. THE FLOW PATTERN IS FORECAST TO EVOLVE INTO A
BROAD...LONGWAVE TROF PATTERN IN THE SOUTHERN STREAM OVER THE
FRONT RANGE OF THE ROCKIES EARLY IN THE WEEK. THE TROF IS FORECAST
TO BE PROGRESSIVE...AIDED BY AND RE-PHASING WITH NRN STREAM
ENERGY...CROSSING THE PLAINS MIDWEEK AND REACHING THE OH/TN
VALLEYS TOWARD THE END OF THE WEEK.
MODEL GUIDANCE SHOWS THINGS DRYING OUT MONDAY NIGHT INTO
TUESDAY...WITH FOCUS SHIFTING TO STRONG STORM SYSTEM EXPECTED TO
TRACK FROM THE FOUR CORNERS THROUGH THE PLAINS AND GREAT LAKES
INTO EASTERN CANADA. CENTRAL PA WILL REMAIN ON THE WARM SIDE OF
THIS DYNAMIC SYSTEM WITH ABOVE NORMAL TEMPS EXPECTED THROUGH
WEDNESDAY...WHICH WILL DRAMATICALLY REDUCE THE CURRENT SNOWPACK
OVER SOUTHERN MTNS AND SUSQ VALLEY.
MODEL BLENDS CONTINUE TO SUPPORT A STRONG SIGNAL FOR PRECIP ON
WEDNESDAY AND MAINTAINED HIGH POPS FOR THIS PERIOD. THE GUIDANCE
APPEARS TO BE FOCUSING A MOD-HVY RAINFALL AXIS ALONG AND TO THE
EAST OF THE APPALACHIANS WHICH SEEMS TIED TO STRONG H85 MSTR FLUX
ANOMS CENTERED WITHIN 40-50KT SWLY PRE-FRONTAL LOW LEVEL JET. THE
FRONTAL BAND PCPN COULD BE CONVECTIVELY ENHANCED WITH WARM SECTOR
PROGGED TO SURGE WELL INTO NEW ENGLAND. FCST MAX TEMPS ARE
CURRENTLY IN THE 48-58F RANGE WHICH COULD BE SUPPORTIVE OF SOME
MARGINAL INSTABILITY.
ALL GUIDANCE POINTS TOWARD A DECENT SHOT OF COLD AIR BEHIND THE
MIDWEEK SYSTEM STARTING THURSDAY /WITH A QUICK SHOT FOR SOME LAKE
EFFECT SNOW SHOWERS/ FOLLOWED BY A REINFORCING SHOT OF COLDER AIR
NEXT WEEKEND.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
POST FRONTAL CIGS BRIEFLY DIPPED INTO IFR RANGE BUT HAVE REBOUNDED
TO LOW MVFR AT BFD/JST. RADAR SHOWS BAND OF LIGHT RAIN PUSHING
E/SE FROM IPT-UNV-JST LINE AND SHOULD CONTINUE TO WEAKEN BEFORE
REACHING MDT/LNS. SFC WIND GUSTS 20-25KT THIS MORNING WILL WEAKEN
BY AFTERNOON WITH MEAN FLOW FROM 280-310 DEGREES. DROPPED LLWS AS
LLJ HAS SHIFTED OUT OF THE AIRSPACE. IMPROVING CONDITIONS ARE FCST
BY THIS EVE WITH RETURN TO VFR AT ALL SITES.
OUTLOOK...
TUE...RAIN/MVFR-IFR CIGS/LLWS DEVELOPING TUESDAY NIGHT.
WED...MVFR WITH POCKETS OF IFR. RAIN SHOWERS. LLWS. GUSTY WINDS
25+KT FROM 160-190 DEGREES SHIFTING TO 270-300 WED PM BEHIND THE
COLD FRONT.
THU...MVFR CIGS/SCT -SHSN WEST. VFR CENTRAL-EAST. LIGHTER WINDS.
FRI...NO SIG WX.
&&
.HYDROLOGY...
LATEST MODEL ENSEMBLE RIVER FORECASTS /MMEFS/ CONTINUE TO INDICATE
POTENTIAL RISK FOR SMALL STREAM FLOODING ACROSS SOUTH CENTRAL AND
SOUTHEAST PA WEDNESDAY INTO THURSDAY/FEBRUARY 3-4. MARFC IS
HIGHLIGHTING THIS THREAT IN THEIR SIGNIFICANT FLOOD OUTLOOK. THE
MAIN AREA OF CONCERN AT THIS TIME IS ACROSS THE JUNIATA AND LOWER
MAIN STEM SUSQUEHANNA BASINS. THE FLOOD RISK WILL BE A COMBINATION
OF SNOWMELT/SATURATED GROUND AND FORECAST MODERATE TO LOCALLY
HEAVY RAINFALL. WE ARE ASSESSING THE FLOOD POTENTIAL AND MAY
CONSIDER ISSUING A FLOOD WATCH LATER TODAY.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/GARTNER
AVIATION...STEINBUGL
HYDROLOGY...LAMBERT/STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
550 AM EST MON FEB 1 2016
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS MORNING.
LOW PRESSURE WILL TRACK WEST OF PENNSYLVANIA DURING THE MIDDLE OF
THE WEEK...PUSHING A TRAILING COLD FRONT THROUGH THE AREA LATE
WEDNESDAY. HIGH PRESSURE WILL BUILD OVER THE REGION LATE NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SLOWLY EASTWARD MOVING AND DWINDLING AREA OF SHOWERS WAS NOTED ON
REGIONAL 88D MOSAIC LOOP AT 10Z...ALONG AND AHEAD OF A COLD FRONT
THAT EXTENDED FROM NEAR KBFD TO KPIT.
08Z HRRR /SIMILAR TO THE PAST SEVERAL RUNS/ SHOWS THE SHOWERS
DISSIPATING TO PRACTICALLY NOTHING AS THEY HEAD OFF THE ALLEGHENY
PLATEAU...AND INTO THE CENTRAL RIDGE AND VALLEY REGION OF THE
STATE...WHERE IN THE ABSENCE OF SIGNIFICANT FORCING...THE
PRE AND POST FRONT SWRLY TO WNWRLY LLVL FLOW WILL HAVE A DECIDED
AND MODERATELY STRONG DOWNSLOPE/DRYING COMPONENT.
THE SHOWERS ARE SEEN TO REFORM ACROSS OUR FAR SE ZONES FOR A FEW
HOURS BETWEEN ABOUT 18-20Z TODAY BEFORE SHIFTING EAST TOWARD THE
NEW JERSEY COAST.
IT WILL START OFF CLOUDY TODAY WITH A CORRIDOR OF ISOLATED-SCT
/AND DIMINISHING/ SHOWERS WORKING FROM THE CENTRAL MTNS TOWARD
THE LOWER SUSQ VALLEY ALONG THE AFOREMENTIONED COLD FRONT.
OTHERWISE...THE PM HOURS SHOULD BE DRY WITH GRADUALLY BRIGHTENING
SKIES ACROSS MUCH OF CENTRAL AND NWRN PENN...AS DRIER AIR AND
HIGH PRESSURE BUILD INTO THE AREA.
TEMPS WEIGHTED ABOUT 75 PERCENT TWD NEW CONSENSUS BLENDED MODEL
GUIDANCE YIELD HIGHS IN THE 40S TODAY /SEVERAL DEG OR MORE COOLER
THAN SUNDAY IN MOST LOCATIONS/ EVEN GIVEN THE COOLER READINGS...
HE HIGH TEMPS WILL STILL AVERAGE SOME 5-10 DEG WARMER THAN NORMAL
FOR THE FIRST DAY OF FEBRUARY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
HIGH PRESSURE RIDGE WILL SLIDE EAST ACROSS THE STATE TONIGHT INTO
TUESDAY...BRINGING FAIR WEATHER WITH A LIGHT NORTHWEST-NE
BREEZE. EXPECT JUST SOME SCATTERED ALTO CU AND CIRRUS CLOUDS
SPREADING OVER THE RIDGE TONIGHT AND TUESDAY MORNING. LOW TEMPS
WILL RANGE FROM 25-30F /;WHICH IS ABOUT 5-10F WARMER THAN NORMAL
ACROSS THE CENTRAL AND EASTERN VALLEY LOCATIONS...AND ABOUT 15 DEG
F ABOVE NORMAL ACROSS THE WESTERN MTNS.
THE SOUTHEAST TO SOUTHERLY LLVL FLOW WILL STRENGTHEN LATER TUESDAY
AND TUESDAY NIGHT...AND WILL HELP TO ADVECT THICKENING MULTI-
LAYERED CLOUDS ACROSS THE REGION.
LATEST BLENDED MULTI-MODEL GUIDANCE AND THE TIMING OF THE HIGH`S
DEPARTURE OFF THE MID ATLANTIC AND NEW ENGLAND COASTS TUESDAY AND
INCREASING AFTERNOON CLOUDS SHOULD YIELD A HIGH TEMP IN THE
40S...TO NEAR 50F ACROSS SOME OF THE HIGHER TERRAIN OF THE SOUTH
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
EXPANSIVE ZONAL FLOW PATTERN...COMBINING THE NORTHERN AND
SOUTHERN STREAMS OF THE MAIN JET...STRETCHES FROM COAST TO COAST
THIS WEEKEND. THE FLOW PATTERN IS FORECAST TO EVOLVE INTO A
BROAD...LONGWAVE TROF PATTERN IN THE SOUTHERN STREAM OVER THE
FRONT RANGE OF THE ROCKIES EARLY IN THE WEEK. THE TROF IS FORECAST
TO BE PROGRESSIVE...AIDED BY AND RE-PHASING WITH NRN STREAM
ENERGY...CROSSING THE PLAINS MIDWEEK AND REACHING THE OH/TN
VALLEYS TOWARD THE END OF THE WEEK.
MODEL GUIDANCE SHOWS THINGS DRYING OUT MONDAY NIGHT INTO
TUESDAY...WITH FOCUS SHIFTING TO STRONG STORM SYSTEM EXPECTED TO
TRACK FROM THE FOUR CORNERS THROUGH THE PLAINS AND GREAT LAKES
INTO EASTERN CANADA. CENTRAL PA WILL REMAIN ON THE WARM SIDE OF
THIS DYNAMIC SYSTEM WITH ABOVE NORMAL TEMPS EXPECTED THROUGH
WEDNESDAY...WHICH WILL DRAMATICALLY REDUCE THE CURRENT SNOWPACK
OVER SOUTHERN MTNS AND SUSQ VALLEY.
MODEL BLENDS CONTINUE TO SUPPORT A STRONG SIGNAL FOR PRECIP ON
WEDNESDAY AND MAINTAINED HIGH POPS FOR THIS PERIOD. THE GUIDANCE
APPEARS TO BE FOCUSING A MOD-HVY RAINFALL AXIS ALONG AND TO THE
EAST OF THE APPALACHIANS WHICH SEEMS TIED TO STRONG H85 MSTR FLUX
ANOMS CENTERED WITHIN 40-50KT SWLY PRE-FRONTAL LOW LEVEL JET. THE
FRONTAL BAND PCPN COULD BE CONVECTIVELY ENHANCED WITH WARM SECTOR
PROGGED TO SURGE WELL INTO NEW ENGLAND. FCST MAX TEMPS ARE
CURRENTLY IN THE 48-58F RANGE WHICH COULD BE SUPPORTIVE OF SOME
MARGINAL INSTABILITY.
ALL GUIDANCE POINTS TOWARD A DECENT SHOT OF COLD AIR BEHIND THE
MIDWEEK SYSTEM STARTING THURSDAY /WITH A QUICK SHOT FOR SOME LAKE
EFFECT SNOW SHOWERS/ FOLLOWED BY A REINFORCING SHOT OF COLDER AIR
NEXT WEEKEND.
&&
.AVIATION /10Z MONDAY THROUGH FRIDAY/...
BAND OF RAIN ALONG COLD FRONT OVER THE NW AIRSPACE SHOULD WEAKEN
AS IT MOVES EAST THIS MORNING. EXPECT VFR TO HOLD FOR THE MOST
PART OVER CENTRAL AND EASTERN SITES. GFS-BASED GUIDANCE HAS BEEN
TOO PESSIMISTIC RECENTLY AND SEEMS OVERDONE WITH IFR VIS INVOF
MDT/LNS. POST FRONTAL CIGS SHOULD LOWER TO MVFR OR EVEN IFR FOR A
TIME TOWARD DAYBREAK. BEHIND FROPA SFC WINDS WILL BE SHIFTING FROM
200-240 TO 280-320 WITH 15-20KT GUSTS DIMINISHING. STRONG WSW LLJ
AHEAD OF COLD FRONT WILL KEEP LLWS MENTION UNTL 09-12Z BEFORE
WEAKENING. IMPROVING CONDITIONS FCST BY THIS EVE WITH RETURN TO
VFR AT ALL SITES.
OUTLOOK...
TUE...MAINLY VFR. RAIN...SUB-VFR CIGS AND LLWS DEVELOPING TUESDAY
NIGHT.
WED...MVFR/IFR. RAIN SHOWERS. LLWS. GUSTY WINDS 25+KT FROM
160-190 DEGREES SHIFTING TO 270-300 WED PM BEHIND THE COLD FRONT.
THU...MVFR CIGS/SCT -SHSN WEST. VFR CENTRAL-EAST. LIGHTER WINDS.
FRI...NO SIG WX.
&&
.HYDROLOGY...
LATEST MODEL ENSEMBLE RIVER FORECASTS /MMEFS/ FOR THE GEFS AND
NAEFS SUGGEST THE POTENTIAL FOR MINOR FLOODING ACROSS SOUTH-
CENTRAL AND SOUTHEAST PA WEDNESDAY INTO THURSDAY/FEBRUARY 3-4.
MARFC ALSO ISSUED A FLOOD OUTLOOK FOR THIS AREA. THE MAIN AREA OF
CONCERN AT THIS TIME IS ACROSS THE JUNIATA AND LOWER MAIN STEM
SUSQUEHANNA BASINS WHERE SNOWMELT RATES WILL BE INCREASING DUE TO
A PROLONGED PERIOD OF MILD/ABOVE NORMAL TEMPERATURES. THE FLOOD
RISK WILL BE A COMBINATION OF SNOWMELT AND RAINFALL. MINOR FLOOD
RISK FOR THE SMALLER STREAMS AND CREEKS IS HIGHLIGHTED IN HWO AND
WILL CONTINUE TO BE MONITORED CLOSELY.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/GARTNER
AVIATION...STEINBUGL
HYDROLOGY...STEINBUGL/LAMBERT
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
950 AM CST MON FEB 1 2016
.DISCUSSION...
FOGGY AT THE COAST AND IN SOME OF THE MARINE AREAS.
FRONTAL BOUNDARY CREPT DOWN TO BRENHAM AND CROCKETT BUT IS
QUICKLY LIFTING NORTH AND WINDS ARE INCREASING ACROSS THE REGION.
THIS SHOULD ALLOW FOR MIXING TO ERODE CLOUDS BENEATH THE VERY
STRONG CAP IN PLACE AND GIVE THE REGION ANOTHER VERY WARM DAY.
FOG STILL HANGING IN THERE AROUND GALVESTON BUT IMPROVING AROUND
MATAGORDA. HAVE EXTENDED THE DENSE FOG ADVISORY THROUGH 6 AM
TUESDAY. THE FOG MAY BE CONCENTRATED RIGHT NEAR THE COAST AND IN
THE UPPER REACHES OF THE BAYS THIS AFTERNOON. FLUCTUATIONS ARE
LIKELY WITH STRONGER WINDS TODAY AND THE VISIBILITIES MAY IMPROVE
FOR A FEW HOURS AT SOME LOCATIONS NEAR THE COAST BUT AS
TEMPERATURES FALL LATE THIS AFTERNOON AND EVENING THE SEA FOG WILL
LIKELY RETURN AND INTRUDE INLAND.
FRONT STILL LOOKS TO BE STRONGLY CAPPED AND HAVE PARED BACK THE
DURATION OF ISOLATED/SCATTERED SHOWERS TO COINCIDE A LITTLE CLOSER
WITH THE FROPA. THE FROPA WILL END THE FOG THREAT AS WELL.
45
&&
.PREV DISCUSSION... /ISSUED 601 AM CST MON FEB 1 2016/
AVIATION...
SEA FOG WAS NOT AS PREVALENT THIS MORNING AS EARLIER THOUGHT. EVEN
SO...IFR TO MVFR CONDITIONS WILL BE SLOW TO IMPROVE THROUGH THE
MORNING. EXPECT A POSSIBLE THREE TO FOUR HOUR WINDOW OF VFR
CONDITIONS FOR MOST INLAND SITES THIS AFTERNOON. WINDS WILL PICK
UP AS WELL AND SHOULD KEEP THE SEA FOG AT BAY OVER THE COASTAL
SITES THROUGH THE EVENING. A PREFRONTAL TROUGH WILL USHER DRIER
AIR INTO SOUTHEAST TEXAS FROM KCLL AND KUTS AFTER 09Z. CONDITIONS
AHEAD OF THIS TROUGH MAY WORSEN OVER THE SITES FROM KCXO TO TO THE
COAST LATE TONIGHT...ESPECIALLY SO IF THE WINDS DIMINISH ENOUGH
FOR SEA FOG DEVELOPMENT AND FOR THE FOG TO SPREAD INLAND.
40
PREV DISCUSSION... /ISSUED 350 AM CST MON FEB 1 2016/
DISCUSSION...
AT 3 AM...A WEAK BOUNDARY SLICED THROUGH THE EXTREME NORTHERN PART
OF SE TX. THE SFC DEW PT AT CALDWELL WAS 46 AND IT WAS 61 AT KCLL
AND 64 AT BRENHAM. THE BOUNDARY WILL WAFFLE A BIT NORTH BEFORE
EVENTUALLY DISSIPATING AND HIGHER DEW PT AIR WILL FILTER TO THE
NORTH. THE OTHER DILEMMA THIS MORNING IS FOG. HRRR IS HANDLING IT
PRETTY WELL AND IS DEPICTING TWO AREAS OF CONCERN. THE FIRST IS
THE SEA FOG AT THE COAST. AS THE FOG MOVES INLAND...THERE APPEARS
TO BE JUST ENOUGH WIND AT 500-1000 FEET TO LIFT THE FOG INTO LIFR
CIGS. THE SECOND AREA OF CONCERN IS OVER THE NW ZONES WHERE
VISIBILITIES HAVE WAVERED BETWEEN 1/2 AND 2 MILES IN FOG. THE HRRR
SHOWS THAT AREA IMPROVING BETWEEN 11-13Z SO WILL HOLD OFF ON ANY
ADVISORY AT THIS TIME. THE HRRR KEEPS THE SEA FOG IN PLACE ALONG
THE COAST FOR MOST OF THE DAY. THERE WILL BE SIGNIFICANT
IMPROVEMENT IN VSBY FOR THE INLAND PORTIONS OF THE COASTAL
COUNTIES BY 10 AM OR SO...BUT THE IMMEDIATE COAST COULD KEEP THE
FOG FOR MUCH OF THE DAY. ALTHOUGH ON THE FENCE...HAVE DECIDED TO
CANCEL THE DENSE FOG ADVISORY FOR WHARTON...FT BEND...HARRIS AND
LIBERTY COUNTIES AS OBSERVATIONS AND WEB CAMERAS SIMPLY DON`T
SUPPORT RESTRICTED VSBYS LESS THAN A 1/4 MILE. WILL MAINTAIN THE
ADVISORY ALONG THE IMMEDIATE COAST.
TEMPS ARE IN THE LOWER/MID 60S SOUTH OF THE BOUNDARY SO IT WON`T
TAKE MUCH HEATING TO BUMP TEMPS INTO THE UPPER 70S THIS AFTERNOON.
NAM/GFS FCST SOUNDINGS DIFFER SIGNIFICANTLY WITH SKY COVER TODAY
AS THE NAM KEEPS THINGS CLOUDY WHILE THE GFS BREAKS OUT SOME AFTN
SUN. A STRONG CAPPING INVERSION IN PLACE SHOULD LIMIT MIXING SO
OPTED TOWARD MORE CLOUDS TODAY.
AN AREA OF LOW PRESSURE OVER SE COLORADO WILL STRENGTHEN TONIGHT
AND TIGHTEN THE GRADIENT SO WINDS SHOULD BEGIN TO INCREASE THIS
AFTERNOON INTO TONIGHT. AS THE LOW PUSHES TO THE NE...A WEAK PRE
FRONTAL TROUGH OR WHAT LOOKS LIKE A DRY LINE SHOULD CROSS THE
AREA. MOISTURE IS LIMITED WITH PW VALUES ONLY AROUND AN INCH.
ATMOSPHERE REMAINS CAPPED SO JUST EXPECTED A BROKEN LINE OF WEAK
SHOWERS TONIGHT INTO EARLY TUESDAY. RAINFALL TOTALS WITH SYSTEM
WILL BE VERY LIGHT WITH MOST LOCATIONS PROBABLY GETTING JUST A
FEW HUNDREDTHS OF AN INCH. A SURGE OF MUCH COLDER TEMPERATURES
DOESN`T ARRIVE UNTIL TUESDAY EVENING. HIGH PRESSURE WILL MOVE
ACROSS THE STATE ON WED/THURS AND EAST OF THE STATE BY FRIDAY
AFTERNOON. THIS FEATURE WILL BRING MUCH COOLER CONDITIONS AND
CLEAR SKIES WED-FRI. A WEAK S/WV TROUGH WILL DIG INTO TEXAS FRI
NITE OR SATURDAY. NOT MUCH MOISTURE FOR THIS SYSTEM TO WORK WITH
BUT ADDED 20/30 POPS AS THE FORCING WITH THIS FEATURE LOOKS RATHER
STRONG. HIGHER POPS OVER THE SOUTHERN HALF OF THE REGION CLOSER TO
THE BEST FORCING AND DEEPER MSTR. 43
MARINE...
AREAS OF DENSE SEA FOG WILL POSSIBLY LIFT THIS AFTERNOON...ALTHOUGH
PATCHY FOG WILL LIKELY CONTINUE. WINDS WILL ALSO INCREASE THIS
AFTERNOON AND EVENING AND HELP TO DISPERSE ANY WIDESPREAD FOG THAT
TRIES TO DEVELOP. STILL THINK THAT THERE WILL BE PATCHY FOG THROUGH
THE NIGHT. THERE IS A GOOD CHANCE THE SEA FOG WILL BECOME DENSE
AGAIN LATE TONIGHT AND EARLY TUESDAY MORNING. FACTORS CONTRIBUTING
WILL BE DIMINISHING WINDS AHEAD OF A COLD FRONT AND POOLING OF
MOISTURE ALONG THE FRONTAL BOUNDARY. IN ANY EVENT...THE FOG THREAT
WILL END WITH THE PASSAGE OF THE FRONT. THE FRONT IS EXPECTED TO
MOVE THROUGH THE BAYS AND OFF THE COAST AROUND OR JUST AFTER
SUNRISE. A REINFORCING FRONT WILL THEN PUSH OFF THE COAST EARLY
TUESDAY EVENING. MODERATE OFFSHORE WINDS WILL DEVELOP BEHIND THE
SECOND FRONT.
40
CLIMATE...
JANUARY HAS COME TO AN END AND THE AVERAGE TEMPERATURE FOR THE
MONTH WAS NEAR TO SLIGHTLY COOLER THAN NORMAL. RAINFALL ACROSS SE
TEXAS WAS WELL BELOW NORMAL WITH MANY LOCATIONS 2 INCHES DRIER
THAN THE 30 YEAR NORMALS. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 56 68 39 56 / 10 20 10 0 0
HOUSTON (IAH) 78 63 74 42 60 / 10 20 20 0 0
GALVESTON (GLS) 69 62 72 48 59 / 10 20 30 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 6 AM CST TUESDAY FOR THE FOLLOWING
ZONES: BRAZORIA...CHAMBERS...GALVESTON...JACKSON...
MATAGORDA.
GM...DENSE FOG ADVISORY UNTIL 6 AM CST TUESDAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...45
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
902 AM CST MON FEB 1 2016
.UPDATE...
A STRATUS DECK CONTINUES TO SURGE NORTH EARLY THIS MORNING AND
WILL LIKELY REACH THE I-20/I-30 CORRIDORS LATE THIS MORNING OR BY
MIDDAY. THIS MAY HAVE SOME EFFECT ON HIGH TEMPERATURES THIS
AFTERNOON ACROSS THE EASTERN COUNTIES. HRRR AND SREF MODELS SEEM
TO LOCK ON TO THE STRATUS WELL...WHILE OTHERS WERE TOO OPTIMISTIC.
AREAS OF FOG...SOME LOCALLY DENSE WILL CONTINUE ACROSS CENTRAL
TEXAS THROUGH 10 AM...BEFORE INCREASING SOUTHERLY WINDS AND
WARMING TEMPERATURES HELP DISPERSE ANY FOG. LOOKING AT FORECAST
SOUNDINGS FOR THOSE MODELS INDICATE THAT THOUGH CEILINGS WILL LIFT
WITH WARMING OF THE LOW LEVELS...DECKS WILL REMAIN BROKEN TO
OVERCAST THROUGHOUT THE DAY AND INTO THIS EVENING.
WE HAVE ADJUSTED HIGHS DOWN INTO THE LOWER 70S IN THE EAST TO
ACCOUNT FOR THE LACK OF INSOLATION AS COMPARED TO EARLIER...BUT
WILL MAINTAIN MID TO UPPER 70S ACROSS THE FAR WEST WHERE SOME
VEERING OF LOW LEVEL FLOW AND AT LEAST PARTIAL SUNSHINE IS
EXPECTED. WE WILL CONTINUE THE RED FLAG WARNING FOR EASTLAND AND
STEPHENS COUNTIES. A GRASS FIRE DANGER STATEMENT CONTINUES AS FAR
EAST AS A BOWIE...TO WEATHERFORD...TO LAMPASAS LINE FOR LOW
AFTERNOON HUMIDITY VALUES ...DRIER FUELS AND WARMER TEMPERATURES.
GUSTY SOUTH WINDS OF 15-25 MPH WILL OCCUR THIS AFTERNOON ACROSS
THE WESTERN COUNTIES...WITH SOUTHEAST WINDS 15-20 MPH ELSEWHERE.
05/
&&
.AVIATION...
/ISSUED 557 AM CST MON FEB 1 2016/
DIFFICULT FORECAST TODAY AS RICH GULF MOISTURE SURGES NORTHWARD
WITH A WARM FRONT. THIS MOIST AIRMASS IS REPLACING A COOLER
AIRMASS AND IS RESULTING IN IFR CIGS AND SOME LIGHT FOG SOUTH AND
SOUTHEAST OF THE TAF SITES THIS MORNING. RAP/HRRR SEEM TO BE THE
ONLY MODELS IDENTIFYING CURRENT TRENDS WELL...AND HAVE WEIGHED
THEIR OUTPUT HEAVILY FOR TAF FORECAST TODAY.
WILL BRING IFR CIGS AND MVFR VSBY INTO WACO AFTER 1330Z WITH CIGS
GRADUALLY LIFTING TO MVFR BY LATE MORNING AND FINALLY ERODING BY
MID AFTERNOON. AS THESE CIGS APPROACH THE METROPLEX THEIR WESTERN
EDGE WILL TEND TO ERODE...BUT IT APPEARS THAT GKY/DAL AND POSSIBLY
DFW WILL CATCH THE WESTERN EDGE OF THEM EARLY THIS AFTERNOON.
HAVE PUT A MENTION OF MVFR CIGS IN ALL METROPLEX TAFS...BUT
THREAT IS MUCH LOWER FOR WESTERN SITES THAN EASTERN SITES. FOR DAL
HAVE SHOWN MVFR ALL AFTERNOON WITH AFW/FTW JUST HAVING A TEMPO MVFR
FOR A COUPLE HOURS EARLY THIS AFTERNOON. FOR DFW/GKY HAVE SET THE
WINDOW OF MVFR FOR 4 HOURS FROM 17/18Z TO 21/22Z. OTHERWISE LIGHT
AND VARIABLE WINDS NOW WILL BECOME SOUTH AND INCREASE TO 15-20KT
WITH HIGHER GUSTS THIS AFTERNOON.
MVFR CIGS WILL LIKELY DEVELOP AGAIN THIS EVENING AHEAD OF A COLD
FRONT WHICH SHOULD ARRIVE AROUND 6Z OR MIDNIGHT LOCAL. SOME WEAK
AMOUNTS OF INSTABILITY ALOFT AND SUFFICIENT MOISTURE SHOULD RESULT
IN A FEW BRIEF SHOWERS AHEAD OF THE FRONT...AND WHILE THUNDER IS
POSSIBLE...THE POTENTIAL LOOKS TOO LOW TO MENTION. VFR BEHIND THE
FRONT WITH WESTERLY WINDS AT 10-15KT WILL PREVAIL INTO TUESDAY.
MAV/LAV GUIDANCE LOOKS TOO HIGH WITH WESTERLY WINDS TUESDAY
MORNING GIVEN ONLY 25KT FLOW AT 850MB AND A SURFACE LOW/UPPER
SYSTEM TRACKING WELL OFF TO THE NORTH OF THE REGION. THUS DO NOT
ANTICIPATE ANY CROSSWIND CONCERNS TUESDAY.
TR.92
&&
.PREV DISCUSSION... /ISSUED 318 AM CST MON FEB 1 2016/
COOLER CONDITIONS ARE CURRENTLY BEING FELT COMPARED TO THIS TIME
YESTERDAY DUE TO THE PASSAGE OF A WEAK COLD FRONT...WHICH HAD
BECOME STATIONARY ALONG THE SOUTHEAST BORDER OF THE FORECAST AREA
THIS MORNING. IN FACT IT LOOKS LIKE THE BOUNDARY HAS ALREADY BEGUN
TO LIFT NORTH IN RESPONSE TO LEE ROCKIES CYCLOGENESIS ASSOCIATED
WITH AN UPPER LEVEL LOW PRESSURE SYSTEM OVER THE SOUTHWEST STATES.
THE UPPER LOW CAN BE SEEN MARCHING EASTWARD ON SATELLITE AND IS
PRODUCING CONVECTION OVER ARIZONA AND NEW MEXICO. THE SYSTEM WILL
CONTINUE ITS EASTWARD ADVANCE TODAY...EVENTUALLY REACHING THE
OKLAHOMA PANHANDLE THIS EVENING BEFORE LIFTING NORTHEAST ACROSS
THE CENTRAL PLAINS TONIGHT AND TUESDAY.
THE SOUTHEASTERN COUNTIES CAN EXPECT FOG DEVELOPMENT THIS MORNING
AS THE MOISTURE RICH AIR ALONG THE FRONT CREEPS IN FROM THE SOUTH.
FOG SHOULD HANG AROUND UNTIL LATE MORNING BUT QUICKLY BURN OFF BY
MIDDAY.
AS FOR THE DEVELOPING STORM OUT WEST...A DEEP SURFACE LOW WILL
ACCOMPANY THE UPPER LEVEL SYSTEM...CREATING A TIGHT PRESSURE
GRADIENT OVER NORTH AND CENTRAL TEXAS AND LEADING TO A WARM AND
WINDY DAY ACROSS THE REGION. THE SOUTH WINDS WILL KICK IN AS THE
SURFACE BOUNDARY OVER THE SOUTHERN COUNTIES LIFTS QUICKLY NORTH
LATER THIS MORNING. SURFACE WINDS SHOULD REMAIN JUST BELOW WIND
ADVISORY CRITERIA...BUT WILL LEAD TO ANOTHER DAY OF HIGH FIRE
DANGER ACROSS THE WEST WHERE THE WARMEST AND DRIEST CONDITIONS
WILL RESIDE. THE TIMING WILL BE DURING THE MID TO LATE AFTERNOON
HOURS AS A DRYLINE NUDGES INTO THE AREA...CREATING MORE OF A
SOUTHWEST WIND COMPONENT ALONG WITH WARMER...DRIER AIR. WE HAVE
DECIDED THAT A RED FLAG WARNING IS NECESSARY FOR THE WESTERN-MOST
COUNTIES FOR THE MID TO LATE AFTERNOON HOURS...WHERE A WINDOW OF
CRITICAL FIRE DANGER WILL BE POSSIBLE.
A COLD FRONT WILL OVERTAKE THE DRY LINE THIS EVENING AS THE STORM
SYSTEM BEGINS TO LIFT NORTHEAST FROM THE OK PANHANDLE/SOUTHWEST
KS INTO THE CENTRAL PLAINS. CONDITIONS ARE EXPECTED TO REMAIN TOO
DRY ACROSS THE WESTERN HALF OF THE REGION FOR ANY PRECIPITATION
ALONG THE FRONT...BUT THERE SHOULD STILL BE ENOUGH MOISTURE FOR A
SLIGHT CHANCE OF SHOWERS AND STORMS ALONG AND EAST OF THE I-35
CORRIDOR LATER THIS EVENING AND OVERNIGHT. IT STILL APPEARS THAT
INSTABILITY WILL REMAIN ON THE LOW SIDE...SO ANY CONVECTION THAT
DEVELOPS WILL LIKELY REMAIN ISOLATED AND SUB-SEVERE.
THE FRONT WILL PUSH EAST OF THE REGION LATE TONIGHT/EARLY TUESDAY
WITH COOLER AND BREEZY CONDITIONS BEHIND IT. A SECOND SURGE OF
COLD AIR WILL ARRIVE AROUND MIDDAY TUESDAY. GOOD COLD AIR
ADVECTION WILL PERSIST TUESDAY NIGHT AND INTO WEDNESDAY AS A
STRONG SURFACE RIDGE BUILDS SOUTH OVER THE AREA. WEDNESDAY/S
TEMPERATURES WILL BEGIN THE MORNING NEAR FREEZING AND STRUGGLE TO
REACH 50 IN MOST LOCATIONS THAT AFTERNOON. LIGHTER WINDS AND
MOSTLY CLEAR SKIES WILL LEAD TO A GOOD RADIATIONAL COOLING NIGHT
WEDNESDAY NIGHT WITH WITH LOWS RANGING FROM THE MID 20S ACROSS THE
NORTHWEST TO LOWER 30S SOUTHEAST.
TEMPERATURES SHOULD RETURN TO NEAR-NORMAL BY FRIDAY AS SOUTHWEST
FLOW DEVELOPS OVERHEAD. ANOTHER UPPER LOW WILL MOVE OVERHEAD LATE
SATURDAY OR SUNDAY...BRINGING A SLIGHT CHANCE OF RAIN THIS
WEEKEND.
30
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 75 49 62 34 50 / 5 10 10 5 5
WACO, TX 77 48 64 34 52 / 5 10 10 5 5
PARIS, TX 70 50 62 33 48 / 10 30 20 10 5
DENTON, TX 74 46 60 31 48 / 5 10 10 5 5
MCKINNEY, TX 73 47 61 32 48 / 5 20 10 5 5
DALLAS, TX 75 50 62 35 50 / 5 20 10 5 5
TERRELL, TX 75 49 63 35 50 / 5 20 10 5 5
CORSICANA, TX 75 50 65 36 52 / 5 20 10 5 5
TEMPLE, TX 80 49 66 34 53 / 5 10 10 5 5
MINERAL WELLS, TX 76 44 60 32 48 / 5 10 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 2 PM THIS AFTERNOON TO 6 PM CST THIS
EVENING FOR TXZ115-129.
&&
$$
92/05
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
601 AM CST MON FEB 1 2016
.AVIATION...
SEA FOG WAS NOT AS PREVALENT THIS MORNING AS EARLIER THOUGHT. EVEN
SO...IFR TO MVFR CONDITIONS WILL BE SLOW TO IMPROVE THROUGH THE
MORNING. EXPECT A POSSIBLE THREE TO FOUR HOUR WINDOW OF VFR
CONDITOINS FOR MOST INLAND SITES THIS AFTERNOON. WINDS WILL PICK
UP AS WELL AND SHOULD KEEP THE SEA FOG AT BAY OVER THE COASTAL
SITES THROUGH THE EVENING. A PREFRONTAL TROUGH WILL USHER DRIER
AIR INTO SOUTHEAST TEXAS FROM KCLL AND KUTS AFTER 09Z. CONDITIONS
AHEAD OF THIS TROUGH MAY WORSEN OVER THE SITES FROM KCXO TO TO THE
COAST LATE TONIGHT...ESPECIALLY SO IF THE WINDS DIMINISH ENOUGH
FOR SEA FOG DEVELOPMENT AND FOR THE FOG TO SPREAD INLAND.
40
&&
.PREV DISCUSSION... /ISSUED 350 AM CST MON FEB 1 2016/
DISCUSSION...
AT 3 AM...A WEAK BOUNDARY SLICED THROUGH THE EXTREME NORTHERN PART
OF SE TX. THE SFC DEW PT AT CALDWELL WAS 46 AND IT WAS 61 AT KCLL
AND 64 AT BRENHAM. THE BOUNDARY WILL WAFFLE A BIT NORTH BEFORE
EVENTUALLY DISSIPATING AND HIGHER DEW PT AIR WILL FILTER TO THE
NORTH. THE OTHER DILEMMA THIS MORNING IS FOG. HRRR IS HANDLING IT
PRETTY WELL AND IS DEPICTING TWO AREAS OF CONCERN. THE FIRST IS
THE SEA FOG AT THE COAST. AS THE FOG MOVES INLAND...THERE APPEARS
TO BE JUST ENOUGH WIND AT 500-1000 FEET TO LIFT THE FOG INTO LIFR
CIGS. THE SECOND AREA OF CONCERN IS OVER THE NW ZONES WHERE
VISIBILITIES HAVE WAVERED BETWEEN 1/2 AND 2 MILES IN FOG. THE HRRR
SHOWS THAT AREA IMPROVING BETWEEN 11-13Z SO WILL HOLD OFF ON ANY
ADVISORY AT THIS TIME. THE HRRR KEEPS THE SEA FOG IN PLACE ALONG
THE COAST FOR MOST OF THE DAY. THERE WILL BE SIGNIFICANT
IMPROVEMENT IN VSBY FOR THE INLAND PORTIONS OF THE COASTAL
COUNTIES BY 10 AM OR SO...BUT THE IMMEDIATE COAST COULD KEEP THE
FOG FOR MUCH OF THE DAY. ALTHOUGH ON THE FENCE...HAVE DECIDED TO
CANCEL THE DENSE FOG ADVISORY FOR WHARTON...FT BEND...HARRIS AND
LIBERTY COUNTIES AS OBSERVATIONS AND WEB CAMERAS SIMPLY DON`T
SUPPORT RESTRICTED VSBYS LESS THAN A 1/4 MILE. WILL MAINTAIN THE
ADVISORY ALONG THE IMMEDIATE COAST.
TEMPS ARE IN THE LOWER/MID 60S SOUTH OF THE BOUNDARY SO IT WON`T
TAKE MUCH HEATING TO BUMP TEMPS INTO THE UPPER 70S THIS AFTERNOON.
NAM/GFS FCST SOUNDINGS DIFFER SIGNIFICANTLY WITH SKY COVER TODAY
AS THE NAM KEEPS THINGS CLOUDY WHILE THE GFS BREAKS OUT SOME AFTN
SUN. A STRONG CAPPING INVERSION IN PLACE SHOULD LIMIT MIXING SO
OPTED TOWARD MORE CLOUDS TODAY.
AN AREA OF LOW PRESSURE OVER SE COLORADO WILL STRENGTHEN TONIGHT
AND TIGHTEN THE GRADIENT SO WINDS SHOULD BEGIN TO INCREASE THIS
AFTERNOON INTO TONIGHT. AS THE LOW PUSHES TO THE NE...A WEAK PRE
FRONTAL TROUGH OR WHAT LOOKS LIKE A DRY LINE SHOULD CROSS THE
AREA. MOISTURE IS LIMITED WITH PW VALUES ONLY AROUND AN INCH.
ATMOSPHERE REMAINS CAPPED SO JUST EXPECTED A BROKEN LINE OF WEAK
SHOWERS TONIGHT INTO EARLY TUESDAY. RAINFALL TOTALS WITH SYSTEM
WILL BE VERY LIGHT WITH MOST LOCATIONS PROBABLY GETTING JUST A
FEW HUNDREDTHS OF AN INCH. A SURGE OF MUCH COLDER TEMPERATURES
DOESN`T ARRIVE UNTIL TUESDAY EVENING. HIGH PRESSURE WILL MOVE
ACROSS THE STATE ON WED/THURS AND EAST OF THE STATE BY FRIDAY
AFTERNOON. THIS FEATURE WILL BRING MUCH COOLER CONDITIONS AND
CLEAR SKIES WED-FRI. A WEAK S/WV TROUGH WILL DIG INTO TEXAS FRI
NITE OR SATURDAY. NOT MUCH MOISTURE FOR THIS SYSTEM TO WORK WITH
BUT ADDED 20/30 POPS AS THE FORCING WITH THIS FEATURE LOOKS RATHER
STRONG. HIGHER POPS OVER THE SOUTHERN HALF OF THE REGION CLOSER TO
THE BEST FORCING AND DEEPER MSTR. 43
MARINE...
AREAS OF DENSE SEA FOG WILL POSSIBLY LIFT THIS AFTERNOON...ALTHOUGH
PATCHY FOG WILL LIKELY CONTINUE. WINDS WILL ALSO INCREASE THIS
AFTERNOON AND EVENING AND HELP TO DISPERSE ANY WIDESPREAD FOG THAT
TRIES TO DEVELOP. STILL THINK THAT THERE WILL BE PATCHY FOG THROUGH
THE NIGHT. THERE IS A GOOD CHANCE THE SEA FOG WILL BECOME DENSE
AGAIN LATE TONIGHT AND EARLY TUESDAY MORNING. FACTORS CONTRIBUTING
WILL BE DIMINISHING WINDS AHEAD OF A COLD FRONT AND POOLING OF
MOISTURE ALONG THE FRONTAL BOUNDARY. IN ANY EVENT...THE FOG THREAT
WILL END WITH THE PASSAGE OF THE FRONT. THE FRONT IS EXPECTED TO
MOVE THROUGH THE BAYS AND OFF THE COAST AROUND OR JUST AFTER
SUNRISE. A REINFORCING FRONT WILL THEN PUSH OFF THE COAST EARLY
TUESDAY EVENING. MODERATE OFFSHORE WINDS WILL DEVELOP BEHIND THE
SECOND FRONT.
40
CLIMATE...
JANUARY HAS COME TO AN END AND THE AVERAGE TEMPERATURE FOR THE
MONTH WAS NEAR TO SLIGHTLY COOLER THAN NORMAL. RAINFALL ACROSS SE
TEXAS WAS WELL BELOW NORMAL WITH MANY LOCATIONS 2 INCHES DRIER
THAN THE 30 YEAR NORMALS. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 56 68 39 56 / 10 20 20 0 0
HOUSTON (IAH) 78 63 74 42 60 / 10 30 30 0 0
GALVESTON (GLS) 69 62 72 48 59 / 10 30 40 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: BRAZORIA...CHAMBERS...GALVESTON...
JACKSON...MATAGORDA.
GM...DENSE FOG ADVISORY UNTIL 10 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS PUEBLO CO
349 PM MST MON FEB 1 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 349 PM MST MON FEB 1 2016
...MORE SNOW ON THE WAY...PARTICULARLY FOR NORTHERN AND EASTERN
PARTS OF THE AREA...
UPPER LOW IS CURRENTLY LIFTING NORTHEASTWARD ACROSS SOUTHERN CO WITH
SFC LOW TAKING SHAPE DOWN AROUND KTAD. DRY SLOT AROUND THE SOUTHERN
SLIDE OF THE SYSTEM HAS WRAPPED NORTHWARD INTO THE SAN LUIS VALLEY
AND SOUTHERN I-25 CORRIDOR...AND DEFORMATION BAND SNOW HAS STARTED
TO PUSH TO THE NORTH OF THE FORECAST AREA INTO NE CO. STILL SEEING
A FAIRLY DECENT FETCH OF MOISTURE AHEAD OF THE UPPER LOW ACROSS
EASTERN PORTIONS OF THE SOUTHEAST PLAINS AND WEB CAMS HAVE SHOWN
SOME BOUTS OF HEAVY SNOW AT TIMES...BUT TEMPERATURES HAVE BEEN A
LITTLE TOO WARM FOR MUCH ACCUMULATION JUST YET. MODELS ARE IN
FAIRLY GOOD AGREEMENT TRACKING AND DEEPENING THE UPPER LOW AS IT
MOVES ACROSS SOUTHERN CO INTO THE FAR SOUTHEAST CORNER OF THE STATE
BY 06Z. AS THIS OCCURS...FORECAST AREA WILL COME UNDER THE COLDER
WRAP AROUND PORTION OF THE STORM WITH SNOW PIVOTING DOWN THE WEST
SIDE...BACK INTO THE SOUTHEAST PLAINS TONIGHT. SO ALTHOUGH SOUTHERN
PORTIONS OF THE SOUTHEAST PLAINS APPEAR TO BE DONE WITH THIS
STORM...THERE IS STILL A SECOND WAVE TO GO...AND LATEST HRRR SHOWS
SNOW SPREADING BACK SOUTHWARD INTO THE KPUB AREA AND INTO LAS ANIMAS
AND BACA COUNTIES LATER THIS EVENING THROUGH THE OVERNIGHT HOURS.
WINDS WILL PICK UP WITH THIS SECOND WAVE AND THAT IS WHEN THE
BLOWING SNOW WILL BECOME MORE OF A CONCERN. WINDS IN LATEST MODEL
SUITES APPEAR TO STAY JUST BELOW THRESHOLDS FOR A BLIZZARD
WARNING...BUT IT COULD COME CLOSE IN KIOWA COUNTY WHERE SOME THE
HEAVIEST SNOW IS PROGGED TO OCCUR. WINDS LOOK A LITTLE TOO LIGHT IN
NORTHERN EL PASO COUNTY AT THIS POINT. BUT THIS WILL BEAR CLOSE
WATCHING THROUGH THE EVENING AND OVERNIGHT HOURS
WESTWARD EXTENT OF THE WRAP AROUND WILL BE THE MOST CHALLENGING PART
OF THIS FORECAST. LATEST HRRR DOES PULL H7 WINDS AROUND FROM THE NE
THIS EVENING...SUGGESTING ANOTHER ROUND OF UPSLOPE FOR THE WET
MOUNTAINS/WET MTN VALLEY/POSSIBLY NORTHERN SANGRES....BUT IT DOESN`T
APPEAR TO SPREAD FAR ENOUGH WEST TO AFFECT MORE THAN JUST THE
EASTERN EDGE OF THE SAN LUIS VALLEY. GIVEN THE VALLEY CENTER AND
WESTERN PORTIONS MAY MISS OUT ON THE SECOND WAVE OF THE STORM...HAVE
OPTED TO DOWNGRADE THE WINTER STORM WARNING TO A WINTER WEATHER
ADVISORY. WILL LEAVE ALL OTHER HIGHLIGHTS UNCHANGED. ANOTHER AREA
THAT MAY GET SLIGHTED FROM THIS EVENT WILL BE THE SOUTHERN SANGRES
AND THE SOUTHERN I-25 CORRIDOR FROM WALSENBURG TO KTAD...BUT ITS
STILL TOO SOON TO SAY AT THIS POINT. THIS AREA MAY HOLD OFF UNTIL
AFTER 06Z BEFORE THEY GET THEIR NEXT CHANCE FOR ACCUMULATIONS. STRONG
NORTHERLY WINDS OFF THE PALMER DIVIDE SHOULD BEGIN TO SHADOW
SOUTHERN EL PASO AND PUEBLO COUNTIES AFTER 3 AM...WITH A DOWNWARD
TREND IN THE SNOWFALL FOR THESE AREAS TOWARDS EARLY MORNING.
WILL ALSO MAINTAIN THE WINTER STORM WARNINGS ALONG THE
CONTDVD...THOUGH LOOKS LIKE GREATEST SNOWFALL WILL OCCUR ACROSS THE
CENTRAL MOUNTAINS IN BETTER PROXIMITY TO THE DEFORMATION BAND. THERE
ARE STILL SOME INSTABILITY SNOW SHOWERS ACROSS THE SOUTHWEST
MOUNTAINS THOUGH SO WILL HANG ONTO THE HIGHLIGHTS FOR NOW. SUSPECT
THE SOUTHWEST MOUNTAINS MAY BE ABLE TO BE PARED OUT OF THE WARNINGS
TOWARDS 12Z TUES.
SYSTEM PULLS EAST OF THE AREA ON TUESDAY AND SHOULD SEE SNOW TAPER
OFF ACROSS EASTERN AREAS IN THE MORNING...WITH WINDS GRADUALLY
DECREASING THROUGH THE DAY. THE MOUNTAINS SHOULD SEE ANOTHER ROUND
OF SNOW SHOWERS IN THE AFTERNOON AS A WEAK WAVE DROPS THROUGH THE
BACK SIDE OF THE UPPER TROF. SNOW ACCUMULATIONS LOOK LIGHT AT THIS
POINT...WITH GENERALLY ANOTHER 1 TO 4 IN THE AFTERNOON. -KT
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 349 PM MST MON FEB 1 2016
TUESDAY NIGHT-WEDNESDAY NIGHT...MODERATE TO STRONG NORTH TO
NORTHWEST FLOW DEVELOPS ACROSS THE REGION AS SECONDARY ENERGY DIGS
ACROSS THE ROCKIES ON THE BACKSIDE OF A BROAD UPPER TROUGH
TRANSLATING ACROSS THE UPPER MIDWEST AND INTO THE CENTRAL CONUS.
WITH THAT SAID...SHOULD SEE SNOW SHOWERS OVER AND NEAR THE HIGHER
TERRAIN DIMINISHING TUESDAY NIGHT WITH CLEARING SKIES ACROSS THE
AREA INTO WEDNESDAY MORNING. COULD SEE SOME LIGHT SNOW OVER THE
PEAKS THROUGH THE DAY WEDNESDAY...WITH INCREASING FLOW ALOFT
WEDNESDAY NIGHT. TEMPERATURES THROUGH THE PERIOD TO REMAIN BELOW
SEASONAL AVERAGES...ESPECIALLY SNOW COVERED AREAS OF THE PLAINS.
THURSDAY-FRIDAY...MODELS INDICATING SHORT WAVE RIDGING BUILDING
ACROSS THE AREA EARLY THURSDAY AS MORE PACIFIC ENERGY DIGS ACROSS
THE WEST COAST AND INTO THE GREAT BASIN. MODELS DIFFER ON WHERE THIS
ENERGY MOVES THURSDAY NIGHT AND FRIDAY...WITH SOME MODELS INDICATING
A PROGRESSIVE WAVE MOVING ACROSS THE NORTHERN AND CENTRAL ROCKIES AS
ANOTHER GROUP OF MODELS ARE DIGGING THE SYSTEM ACROSS THE SOUTHERN
ROCKIES. AT ANY RATE...SHOULD SEE INCREASING CHANCES OF LIGHT SNOW
FOR AREAS OVER AND NEAR THE HIGHER TERRAIN THURSDAY NIGHT THROUGH
THE DAY FRIDAY...WITH TEMPERATURES REMAINING BELOW SEASONAL NORMS.
SATURDAY-MONDAY...ANOTHER SHORT WAVE DIGGING DOWN THE BACKSIDE OF A
DEVELOPING LONG WAVE TROUGH ACROSS THE CENTRAL CONUS COULD BRING A
FEW MORE SHOWERS TO MAINLY THE HIGHER TERRAIN ON SUNDAY...WITH DEEP
MERIDIONAL FLOW PROGGED ACROSS THE REGION INTO EARLY NEXT WEEK AS
UPPER LEVEL RIDGING BUILDS ACROSS THE WEST COAST.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 349 PM MST MON FEB 1 2016
IFR TO LIFR CONDITIONS EXPECTED AT KCOS AND KPUB TERMINALS THROUGH
THE EVENING AND OVERNIGHT HOURS WITH CIGS LIFTING AND SNOW TAPERING
BACK AFTER 09Z. STRONG NORTH WINDS WILL BEGIN TO AFFECT KCOS AND
KPUB AROUND 02-03Z WITH GUSTS TO AROUND 30 KTS POSSIBLE. THESE
WINDS WILL CONTINUE INTO THE EARLY MORNING HOURS...EVEN AS SNOW
DIMINISHES AFTER 09Z AND COULD KEEP SOME RESTRICTIONS TO VIS IN
BLSN...ESPECIALLY AT KCOS. BY TUESDAY MORNING...EXPECT IMPROVING
CONDITIONS...THOUGH NORTH WINDS WILL REMAIN GUSTY THROUGH THE
AFTERNOON. KALS WILL SEE VFR CONDITIONS...WITH ANOTHER ROUND OF
MVFR TO BRIEFLY IFR CONDITIONS POSSIBLE THIS EVENING WITH -SHSN.
CONDITIONS WILL RETURN TO VFR QUICKLY OVERNIGHT WITH VFR CONDITIONS
EXPECTED THROUGH TUESDAY. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 11 AM MST TUESDAY FOR COZ058>068-
072>089-093>098.
WINTER WEATHER ADVISORY UNTIL 11 AM MST TUESDAY FOR COZ069>071-
099.
&&
$$
SHORT TERM...KT
LONG TERM...MW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
305 PM EST MON FEB 1 2016
.DISCUSSION...
...AREAS OF DENSE FOG POSSIBLE TONIGHT...
TONIGHT/TUE...
THE MAIN FORECAST PROBLEM WILL BE THE EXTENT OF FOG FORMATION
LATE TONIGHT. LOCAL WRF MODELS AND THE HRRR SHOW AREAS OF DENSE
FOG FORMING. THE 12Z GFS MOS ONLY HINTS AT IT ACROSS NORTHERN
SECTIONS. THIS IS PRETTY TYPICAL AS ONE OF THE PREDICTORS IN THE
MOS EQUATIONS IS CURRENT VISIBILITY...AND THERE WAS NO FOG AT 12Z.
THE FORECAST SOUNDINGS SHOW NO EVIDENCE OF OVERNIGHT STRATOCUMULUS
EVEN THOUGH MOS SUGGESTS SOME. THE CURRENT CLOUD FIELD DOES NOT
LOOK REAL EXTENSIVE...SO THINK THAT THERE WILL BE LONG PERIODS OF
MOSTLY CLEAR SKIES. FORECAST SOUNDINGS SHOW SOUTHEAST WINDS JUST
OFF THE SURFACE AROUND 10 KNOTS...BUT THE MODELS HAVE NOT HANDLED
THE MUDDLED PRESSURE PATTERN THE LAST COUPLE DAYS VERY WELL...SO
DO NOT THINK THAT BOUNDARY LAYER WINDS WILL BE A BIG FOG
INHIBITOR. WILL HOLD ONTO THE CURRENT FORECAST WHICH HAS AREAS OF
FOG INLAND/NORTH COAST AND PATCHY FOG ELSEWHERE. THE NEXT SHIFT
CAN EVALUATE LOW LEVEL WIND/CLOUD TRENDS AND POSSIBLY BUMP UP
WORDING TO MENTION DENSE FOG.
OTHERWISE...OVERNIGHT LOWS WILL RANGE FROM AROUND 60 IN THE FAR
NORTH TO MID 60S IN THE SOUTH. IT WILL BE QUITE WARM TUE WITH
HIGHS REACHING 80 DEGREES AT MOST PLACES AND IN THE LOWER/MID 80S
OVER THE INTERIOR. DID SHAVE A DEGREE OR SO OFF OF MOS MAX TEMPS
THOUGH FOR THE EXPECTED EARLY MORNING FOG/STRATUS.
TUE NIGHT...
FRONT OVER THE SOUTHEAST U.S. GULF COAST AND NORTH GULF OF MEXICO
PUSHES TO THE NORTHEAST GULF AND FLORIDA PANHANDLE. FRESHENING
SOUTHWEST LOW AND MID LEVEL FLOW FEEDS GULF MOISTURE INTO FLORIDA
WITH PRECIPITABLE WATER VALUES INCREASING TO OVER 1.5 INCHES
NORTHERN FORECAST AREA. POP STILL NOT MENTIONABLE AS MID AND UPPER
LEVEL SUPPORT...VORTICITY AND DIVERGENCE...WEST OF CENTRAL
FLORIDA.
WED-FRI...
FRONT STARTS OUT OVER THE NORTHEAST GULF AND FLORIDA BIG BEND
AREA WED THEN WORKS ITS WAY TO SOUTH FLORIDA OVERNIGHT THU AND
FRI. PRECIPITABLE WATER VALUES TO AROUND 2 INCHES AHEAD OF THE
FRONT WITH HIGHEST VALUES OCCURRING THU. BEST VERTICAL ASCENT
ASSOCIATED WITH THE RIGHT REAR QUADRANT OF THE 250MB JET CROSSING
OVERHEAD AND POSITIVE VORTICITY ADVECTION SHOULD PRODUCE LIKELY
POPS FOR THU AND THU NIGHT.
PREVIOUS EXTENDED...
SAT-MON...SHORTWAVE OVER THE SOUTHERN PLAINS LATE IN THE WEEK IS
SHOWN AT VARYING SPEEDS PIVOTING INTO THE SOUTHERN STREAM AND
COMBINING WITH A ROBUST SUBTROPICAL JET TO PRODUCE SFC CYCLOGENESIS
OVER THE CENTRAL TO EASTERN GULF DURING NEXT WEEKEND.
TIMING IS QUESTIONABLE AS FAR AS LOCAL EFFECTS SHOULD THIS FEATURE
QUICKLY EJECT ACROSS FL ROUGHLY DURING NEXT WEEKEND TO EARLY NEXT
WEEK. THE FEATURE DOES LOOK ENERGETIC AT THIS EARLY STAGE HOWEVER
AND WL HAVE TO BE MONITORED LATE THIS WEEK.
&&
.AVIATION...
SEE THE TONIGHT/TUE DISCUSSION ABOVE ABOUT FOG FORMATION.
TRENDED CEILINGS AND VISIBILITY DOWN IN LAST SET OF TERMINAL
FORECASTS. AS CLOUD AND LOW LEVEL WIND TRENDS BECOME MORE
APPARENT...EXPECT THAT THIS DOWNWARD TREND WILL CONTINUE AND
THERE IS A CHANCE FOR LIFR ESPECIALLY AT THE INLAND SITES. EXPECT
CONDITIONS TO IMPROVE BY 15Z TUE AS LOW LEVEL WINDS ARE FORECAST
TO BE IN AN INCREASING STAGE THEN.
&&
.MARINE...
TONIGHT-TUE...
THE PRESSURE GRADIENT CONTINUED LIGHT EARLY THIS AFTERNOON BUT
THE MODELS CONTINUE TO TREND TOWARDS A MORE CONSOLIDATED HIGH
PRESSURE RIDGE DEVELOPING TONIGHT WITH AN AXIS TO OUR NORTH. THE
RESULTANT SOUTHEAST WINDS WILL BE 10 KNOTS OR LESS. THE PRESSURE
GRADIENT WILL START TO TIGHTEN ON TUE AS FRONTAL BOUNDARY ENTERS
THE WESTERN GULF OF MEXICO. SOUTHEAST WINDS WILL INCREASE TO
AROUND 15 KNOTS IN THE AFTERNOON AND 15-20 KNOTS TUE NIGHT.
AREAS OF SEAS FOG ARE POSSIBLE NEAR THE COAST LATE TONIGHT AND
EARLY TUE MORNING...ESPECIALLY NORTH OF SEBASTIAN INLET TO VOLUSIA
COUNTY.
WED-SAT...
POOR BOATING CONDITIONS WILL CONTINUE WED AHEAD OF THE FRONT
MOVING ACROSS THE SOUTHEAST U.S. AND NORTH GULF OF MEXICO. THE
FRONT PUSHES ACROSS THE WATERS THU AND CLEARS THE SOUTHERN AREAS
FRI THEN ALL BUT STALLS OVER THE FLORIDA STRAITS...CUBA AND NORTH
BAHAMA ISLANDS FRI NIGHT AND SAT. HIGH PRESSURE BUILDS IN BEHIND
THE FRONT FRI AND SAT.
SOUTHEAST TO SOUTH WINDS 15 KNOTS WED THRU THU AFTERNOON SHIFT TO
THE WEST AND NORTHWEST THU 15 TO 20 KNOTS NEARSHORE AND 20 KNOTS AND
HIGHER OFFSHORE THU NIGHT AND FRI. WINDS SHIFT TO THE NORTH AND
NORTHEAST 20 KNOTS OR MORE AS HIGH PRESSURE BUILDS IN BEHIND THE
FRONT.
SEAS 3 TO 5 FEET THROUGH THU AFTERNOON BUILD TO 7 TO 10 FEET BY
FRI EVENING AND REMAIN THERE SAT.
&&
.FIRE WEATHER...NO LOW RH CONCERNS THROUGH THE END OF THE WORK
WEEK BUT THERE ARE FOG CHANCES...ESPECIALLY TONIGHT WHERE AREAS OF
DENSE FOG ARE POSSIBLE. COMPUTER GUIDANCE SHOWS THAT WINDS WILL
INCREASE TUE NIGHT AND EARLY WED...SO WHILE PATCHY FOG IS POSSIBLE...
IT APPEARS THAT THE PATTERN WILL FAVOR MORE LOW STRATUS RATHER
THAN DENSE FOG.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 60 79 65 80 / 10 10 10 30
MCO 62 83 66 83 / 10 10 10 20
MLB 65 80 68 82 / 10 10 10 10
VRB 63 81 66 82 / 10 10 10 10
LEE 62 83 67 80 / 10 10 10 30
SFB 62 82 64 82 / 10 10 10 20
ORL 63 82 66 81 / 10 10 10 20
FPR 63 81 68 82 / 10 10 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...LASCODY
LONG TERM....WIMMER
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1104 AM CST MON FEB 1 2016
.UPDATE...
ISSUED AT 1055 AM CST MON FEB 1 2016
Area of dense fog this morning to the NW is persisting through
midday, NW of the Illinois River Valley. Temps still lingering
just below the freezing mark, resulting in some freezing fog and
temperatures at least 10 degrees behind the diurnal swing. Have
updated the grids with a significant drop to the MaxT in that
region. Remainder of the forecast area looks to be on track.
Updates out momentarily.
&&
.SHORT TERM...(Today)
ISSUED AT 234 AM CST MON FEB 1 2016
High pressure advancing eastward into Illinois today will bring
cooler air to central Illinois, along with dry conditions. Early
morning temperatures dipping below freezing west and north of Peoria
could create black ice for untreated roads, especially bridges and
overpasses. Satellite images indicate a steady stream of high cirrus
clouds will be present for most of the day today, which should help
to preclude much in the way of thicker fog formation early this
morning. The cooler start and filtered sunshine will produce high
temperatures 10 to 15 degrees cooler than yesterday, but still well
above normal. Highs should reach the mid 40s along and north of
I-74, with lower 50s south of I-70. Winds will be relatively
light today under the surface ridge axis, with wind directions
eventually becoming easterly this afternoon.
.LONG TERM...(Tonight through Sunday)
ISSUED AT 234 AM CST MON FEB 1 2016
Long-advertised winter storm system taking shape across the
southwest U.S. early this morning, with upper low over southern
California and the surface low just east of Las Vegas at 2 am. The
model consensus continues to favor a track across the Oklahoma
panhandle this evening, then northeast across northern Missouri
Tuesday afternoon before reaching the general vicinity of Chicago by
early evening. With us on the south side of the track, the main
concern will be with convective trends, followed by precipitation
trends as the system pulls away Tuesday night.
Have removed the mention of slight chance of freezing rain across
the far northern CWA late tonight, as temperatures appear to stay in
the mid 30s overnight in that area. Forecast soundings do support
some sleet/snow mixing with the rain at first toward Galesburg,
before a quick transition to rain. Rain chances before sunrise will
mainly be west of I-55, as a stiff east wind will slow the column
moistening a bit. However, showers will quickly overspread the
forecast area Tuesday morning. Latest SPC Day2 outlook extended the
marginal risk of severe weather as far northwest as a Bloomington to
Springfield line, with the slight risk as far north as Mattoon and
Paris. Still a significant amount of shear progged in the lower
levels, with 0-6km bulk shear over 80 knots and an 850 mb jet of 60-
65 knots over the eastern CWA this afternoon. With these numbers,
some damaging winds may result with the stronger storms. Have
mentioned a chance of storms over most of the CWA in the afternoon,
but the more organized line will likely be taking shape along the
I-57 corridor around mid afternoon before racing east.
Dry slot continues to be favored by most of the model guidance, with
this feature punching northeast. Several already bring this into the
western CWA by late afternoon, and over most of the CWA in the
evening, and thus the forecast has been trended toward a period of
slight chance/no chance PoP`s in the evening. Overnight, some slight
chances remain warranted through, as the secondary trough axis
swings through. More substantial deformation-type precipitation
generally progged to stay just to our north, but some flurries are
likely to occur into Wednesday morning.
Remainder of the forecast currently expected to remain fairly quiet.
GFS and ECMWF models favor long wave troughs passing through, but
both keep the coldest air bottled up in Canada, so coldest temps on
Wednesday/Thursday still expected to top out in the 30s most areas.
Both favor a more substantial surge of colder air early next week,
beyond the current forecast period.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
ISSUED AT 556 AM CST MON FEB 1 2016
Main concern through the early morning hours will be the threat
for some lower vsbys in fog with the better threat near KPIA in
the 13z-15z time frame. Weak high pressure advancing into central
Illinois is setting up an inversion, trapping low level moisture
near the ground. Satellite images show an area of LIFR clouds and
IFR VIS approaching PIA from the NW. HRRR output indicates it
could reach as far east as PIA between 13z-16z, but confidence is
low on the southern extent of those conditions. Therefore, have
continued to show just MVFR fog in a tempo through 15z and SCT004
clouds. Light MVFR fog has been developing toward CMI and east of
there, but no significant fog is expected near CMI. Otherwise, VFR
conditions should prevail at the terminal sites for a majority of
the next 24 hours.
Winds will remain light and variable under the surface ridge axis
for much of the day. Winds are expected to become easterly late
this afternoon and evening. As the low pressure system approaches
late tonight, easterly surface winds will increase to around 15kt
sustained.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...Shimon
LONG TERM...Geelhart
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS DES MOINES IA
410 PM CST MON FEB 1 2016
.SHORT TERM /TONIGHT/...
ISSUED AT 409 PM CST MON FEB 1 2016
FORECAST FOCUS REMAINS SQUARELY ON TIMING AND IMPACTS ASSOCIATED
WITH THE IMPENDING WINTER STORM. 12Z UPPER AIR ANALYSIS AND WATER
VAPOR IMAGERY SHOW THE LARGE NEGATIVE TILT UPPER TROUGH EMERGING IN
THE LEE OF THE ROCKIES. IN RESPONSE...SFC CYCLOGENESIS CONTINUES TO
INTENSIFY ACROSS THE CENTRAL PLAINS WITH MAX SFC PRESSURE FALLS OF 6-
MB/3HR NOTED OVER KS/OK. ALTHOUGH HIGH CLOUDS CONTINUE TO SPREAD
NORTHEASTWARD ACROSS THE STATE...MRMS RADAR MOSAIC AND OBSERVATIONS
CONTINUE TO INDICATE ALL THE MEASURABLE PCPN REMAINING OVER NE/KS AS
OF THIS AFTERNOON.
THIS EVENING THROUGH 10PM...SHORT RANGE MODEL GUIDANCE CONTINUE TO
INDICATE THAT A MAJORITY OF THE EVENING SHOULD REMAIN DRY AS MODEL
TIME SECTIONS AND SOUNDINGS SHOW A FAIR AMOUNT OF DRY AIR IN THE LOW
TO MID LEVELS /E.G. 850MB/. LATEST RUNS OF THE HRRR CONTINUE TO
INDICATE THE POTENTIAL FOR A NARROW E/W BAND OF PRECIPITATION
LIFTING NWD ACROSS AREA ALONG THE LEADING SURGE OF ISENTROPIC
ASCENT. HOWEVER...ANY PRECIP /LIKELY A RAIN/SNOW MIX/ WITHIN THIS
BAND SHOULD REMAIN VERY LIGHT...WITH ONLY MINOR SNOW ACCUMS.
TONIGHT AFTER 10 PM...IMPRESSIVE SURGE OF MOISTURE AND LIFT WILL
BEGIN TO IMPACT THE REGION FROM THE SOUTHWEST. COMBINATION OF VERY
STRONG ISENTROPIC LIFT...FRONTOGENETIC FORCING...AND LOWER STATIC
STABILITY SHOULD YIELD ARE LARGE SWATH OF MODERATE TO HEAVY
PRECIPITATION. WOULD NOT BE SURPRISED TO SEE A FEW LIGHTNING STRIKES
TOWARDS 12Z TUE AS WELL DUE TO A PLUME OF VERY STEEP LAPSE RATES
ALOFT CONTRIBUTING TO 100-200 J/KG OF MUCAPE. PORTIONS OF FAR
SOUTHERN IOWA WILL LIKELY BEGIN AS A PERIOD OF MIXED
PRECIPITATION...HOWEVER THE COMBINATION OF VERY STRONG ADIABATIC
ASCENT...AND WET BULB EFFECTS IN THE PBL SHOULD RESULT IN FAIRLY
QUICK CHANGEOVER TO SNOW EXCEPT ALL BUT THE FAR SOUTHEASTERN
COUNTIES.
.LONG TERM /TUESDAY THROUGH MONDAY/...
ISSUED AT 409 PM CST MON FEB 1 2016
PLENTY TO DISCUSS WITH ALL EYES STILL FOCUSED ON IMPENDING WINTER
STORM. LONG WAVE TROUGH IN QUESTION IS STILL ONLY MOVING THROUGH THE
FOUR CORNERS AREA BUT MID LEVEL FORCING EFFECTS ARE ALREADY
APPROACHING THE MS RIVER VALLEY WITH MAINLY VIRGA FOR NOW. THIS WILL
LIFT NORTHWARD INTO IA AT PERIOD ONSET AND MATURE COMBINING WITH
IMPRESSIVE BAROCLINIC ZONE NOW FORMING FROM KS INTO MO. THETA-E
ADVECTION...FRONTOGENETIC AND KINEMATIC FORCING ARE ALL VERY
STRONG AND IMPRESSIVELY PHASED EARLY IN THE PERIOD...BUT SOME
CONCERN IS THAT MUCH OF THIS LIFT IS BELOW THE DENDRITIC GROWTH
ZONE /DGZ/...WHICH IS NOT THAT DEEP ANYWAYS...AND MAY LEAD TO
LOWER RATIOS. HOWEVER CONVECTIVE SNOW IS ALSO A CONCERN WITH
UPRIGHT CONVECTION OVERWHELMING ANYTHING THAT MAY BE SLANTWISE/CSI
AS MOST MODELS ARE DEPICTING TOKEN MUCAPES. CONVECTION ALLOWING
MODELS ALL REFLECT THIS AS WELL WITH SHOWERY 40-50 DBZ ECHOES IN
SNOW. THUS 1-2 INCH/HOUR RATES ARE QUITE POSSIBLE FROM SOUTHERN
INTO CENTRAL IA AROUND THE MORNING COMMUTE. EXAMINATION OF NAM
CONVECTIVE PRECIP FIELDS SUPPORTS THIS AS WELL...EVEN BRINGING
SPOTTY AMOUNTS TOWARD THE MN BORDER. HAVE EVEN ADDED FLAT OUR
THUNDERSTORM WORDING SE.
WELL ADVERTISED DRY SLOT HAS BECOME EVEN MORE PROMINENT THIS MORNING
AND LOOKS TO DIMINISH PRECIP CHANCES SOUTH INTO THE AFTERNOON WITH
TEMPERATURES AT OR ABOVE FREEZING. THERE COULD VERY WELL BE A BRIEF
PERIOD OF LIGHT FREEZING RAIN TOO AS THE DRY SLOT...RAIN/SNOW LINE
LIFTS NORTHWARD THROUGH THE DAY. ADEQUATE LIFT MAY STILL PHASE WITH
A DECENT MOISTURE DEPTH...ALTHOUGH NOT DEEP AND COOL ENOUGH TO ADD
ICE INTRODUCTION. HOWEVER FARTHER NORTH THE DGZ DEEPENS SOMEWHAT AND
BETTER PHASES WITH THE MAX OMEGA AND SHOULD RESULT IN VERY HEAVY
SNOW ACROSS THE NW THIRD OF THE FORECAST AREA INTO THE EVENING AS
THE DEFORMATION ZONE LINGERS AND PIVOTS OVER THESE LOCATIONS.
ALTHOUGH DIFFICULT TO INJECT INTO THE FORECAST AT THIS POINT THE
OPERATIONAL NAM AND COMPANION NMM CORES DEVELOP WHAT LOOKS TO BE
CONVECTIVE PRECIP JUST NW OF THE SURFACE LOW TRACK EARLY TUE
EVENING...WHICH COULD RESULT IN A HEAVY BURST OF UNDETERMINED WINTRY
PRECIP BEING RIGHT IN THE VICINITY OF THE PRECIP TYPE TRANSITION
LINE. THIS WILL HAVE TO BE WATCH WITH TIME...ESPECIALLY INTO TUE.
TRUE BLIZZARD CONDITIONS MAY BE SOMEWHAT MARGINAL THROUGH THE EVENT
WITH 1/4SM VISIBILITIES AND 35 MPH GUSTS NOT COUPLED FOR EXTENDED
PERIODS AS ONE WIND SURGE MOVES THROUGH TUE...AND THEN SWINGS BACK
THROUGH LATE TUE NIGHT. MOST MODELS DO NOT SHOW TOO DEEP OF MIXING
SO GENERALLY KEPT MAX WIND GUSTS 35-40 MPH. GFS BUFR SOUNDINGS DO
INDICATE SOME POTENTIAL FOR GUSTS EXCEEDING THAT...AND MAY OCCUR
LOCALLY...BUT CONFIDENCE IS NOT THERE TO INJECT INTO THE FORECAST ON
A WIDESPREAD BASIS AS OF YET.
WHAT THIS ALL AMOUNTS TO FOR THE SENSIBLE WEATHER FORECAST IS LITTLE
CHANGE FOR SNOW AMOUNTS IN THE CURRENT BLIZZARD WARNING WITH AMOUNTS
LOWERED SOMEWHAT IN THE WINTER STORM WARNING STRIPE...INCLUDING THE
DES MOINES METRO AREA. BLIZZARD WARNING 8-12...WINTER STORM WARNING
4-9...AND A TIER OF WINTER WEATHER ADVISORY GENERALLY 2-4.
SOME MINOR BLOWING SNOW MAY LINGER INTO WEDNESDAY BUT THE REMAINDER
OF THE FORECAST WILL BE RELATIVELY DRY AND INACTIVE WITH SEASONAL
TEMPERATURES. DRY NW FLOW WILL PERSIST INTO INTO THE WEEKEND BEFORE
THE NEXT ITERATION OF WRN CONUS LONG WAVE TROUGH DEVELOPS TO END THE
WEEKEND. A SHORT WAVE DROPS THROUGH THU BUT IS MOISTURE
STARVED...AND THERE COULD BE SOME TOKEN LIGHT SNOW WITH THE COLD
ADVECTION SURGE MON BUT CHANCES ARE NOT HIGH ENOUGH TO INCLUDE AT
THIS TIME. THE BIGGEST SENSIBLE WEATHER CHANGE IN THE EXTENDED
WILL LIKELY BE COLDER TEMPERATURES...WHICH ARE MAINLY JUST BEYOND
THE VALID PERIOD.
&&
.AVIATION...01/18Z
ISSUED AT 121 PM CST MON FEB 1 2016
FOG CONTINUES TO LINGER AT KALO AND KOTM...BUT EXPECT VISIBILITY
TO IMPROVE BY 20-21Z. VFR CONDITIONS ARE THEN EXPECTED FOR
ALL TERMINALS THOUGH THE EVENING HOURS.
MAJOR STORM SYSTEM WILL BEGIN TO IMPACT THE AIRFIELDS AFTER ABOUT 04Z
TONIGHT. EXPECT MVFR CIGS AND VSBYS ASSOCIATED WITH LIGHT SNOW TO
SPREAD FROM WEST TO EAST WITH CONDITIONS DETERIORATING TO
IFR BETWEEN 09Z AND 12Z. MODERATE TO HEAVY SNOWFALL WITH VSBYS
AOB 1/2SM SHOULD IMPACT MOST AIRFIELD BETWEEN 12-18Z.
CORRESPONDING CIGS WILL RANGE FROM IFR TO LIFR. SNOWFALL RATES
WILL LIKELY APPROACH 1 INCH PER HOUR AT TIMES CHALLENGING
RUNWAY MAINTENANCE. COULD SEE MORE OF A RAIN/SNOW MIX AT KOTM DUE
TO WARMER CONDITIONS NEAR THE SURFACE.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 AM CST WEDNESDAY
FOR ADAIR-ADAMS-AUDUBON-BOONE-CASS-DALLAS-GUTHRIE-MADISON-POLK.
WINTER WEATHER ADVISORY FROM 3 AM TUESDAY TO 6 AM CST WEDNESDAY
FOR CLARKE-JASPER-POWESHIEK-RINGGOLD-TAMA-TAYLOR-UNION-WARREN.
BLIZZARD WARNING FROM 3 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
CERRO GORDO-EMMET-FRANKLIN-HAMILTON-HANCOCK-HUMBOLDT-KOSSUTH-
PALO ALTO-WINNEBAGO-WORTH-WRIGHT.
WINTER STORM WARNING FROM 3 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
BLACK HAWK-BREMER-BUTLER-GRUNDY-HARDIN-MARSHALL-STORY.
BLIZZARD WARNING FROM MIDNIGHT TONIGHT TO 6 AM CST WEDNESDAY FOR
CALHOUN-CARROLL-CRAWFORD-GREENE-POCAHONTAS-SAC-WEBSTER.
&&
$$
SHORT TERM...FOWLE
LONG TERM...SMALL
AVIATION...FOWLE
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
325 PM CST MON FEB 1 2016
.SHORT TERM...(This Evening through Tuesday Night)
Issued at 250 PM CST MON FEB 1 2016
The incoming storm system is, more or less, evolving as advertised
this Monday afternoon. Surface cyclogenesis is ongoing while a broad
but so far loosely organized precipitation shield is overspreading
much of western Kansas, Colorado, and into Nebraska. In the local
area, light rain will be possible into early evening as these weak
impulses move across the region with areas of light precipitation.
This may mix with periods of snow mainly in/near Republic county but
accumulation should be pretty much 0 through 9 PM or so.
The main precipitation shield will move out of central Kansas and
across the local area between roughly 10 PM and 6 AM. Expect to see
embedded thunderstorms within this area of moderate rain, with an
isolated lightning strike or two not out of the question even within
the snow area. Instability is not particularly strong and the storms
will be mainly elevated, but with the very strong winds just above
the surface, there is a small chance for a few downdrafts to bring
some locally stronger winds down to the surface. Within the rain
area, expect generally from 0.50 to 1 inch of rain.
The snow forecast remains quite difficult even only a few hours in
advance of the storm. And really, the only reason it remains
difficult is because the rain/snow cutoff line continues to
fluctuate slightly regarding the location of what should be a very
sharp gradient in snow amounts. Additionally, warm ground
temperatures and even warm air temperatures during snowfall will
induce a bit of melting and compacting more than normal. At the same
time, when the snow does begin, the rates should be extremely heavy
with convective snowfall initially and transitioning to more of a
frontogenesis and dynamics-driven snowfall which should still see
moderate rates. Would not be surprised to see snowfall rates exceed
2" per hour for a couple of hours within the heavy snow area. Models
remain in fairly good agreement in terms of where the snow/rain
cutoff will be throughout the night, but still with enough of a N/S
variation to keep question marks in the snow total forecast. High-
Res guidance such as the HRRR and RAP seem to be initializing a bit
warm but still get cold enough in far northwest parts of the CWA
during the heavy precip period to support heavy snow accumulation.
Still looking for the winter-storm-type accumulation amounts near
and north of the Concordia to Washington line, with sharply lower
amounts south of that line.
There appears to be a high likelihood that the dry slot will
overspread the majority of the forecast area during the day on
Tuesday, although again with a rather sharp dry-to-snow cutoff in
the far northwest corner of the forecast area so some additional
snow will remain possible during the morning within the warned area.
Then during the afternoon or early evening, a vort max will wrap
around the main system and may support another quick shot of light
snow on the order of an inch or more, mainly in areas north of I-70.
Winds will continue to be an issue for any areas that experience
heavy snow as there will be some reduced visibility and drifting.
Should note though that the winds appear to have a lull on Tuesday
as the center of the surface low moves overhead.
.LONG TERM...(Wednesday through Monday)
Issued at 250 PM CST MON FEB 1 2016
No major changes needed in the extended as upper wave pattern favors
a dry northwest flow with upper troughs passing to the northeast and
southwest of the CWA. Northwest winds are initially gusty behind the
departing wave Wednesday morning, before gradually diminishing to
around 10 mph at sunset. Cold air advecting from the snowpack in
Nebraska was shown in decent agreement with respect to temperatures
on Wednesday and Thursday with readings in the 30s and overnight
lows in the teens and 20s. Southerly winds return Thursday onward
with mostly sunny skies return and highs rebound to the upper 40s
through the weekend. Next cold front and potential system arrives by
Monday with much uncertainty in guidance on any available
moisture.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon)
Issued at 1144 AM CST MON FEB 1 2016
Very challenging 24 hour period for the 18z TAF forecast.
Generally, this afternoon should remain VFR with increasing
easterly winds beginning to gust into the 20kt range. Into the
overnight period expecting precip in the form of rain and even
some thunderstorms at the KTOP/KFOE terminals. As the storm system
approaches the terminals and begins to deepen more, winds will
continue to increase and gust up to the 30kt range. Beginning
around the 4z and up until the 13z time frame, expect to see
CIG/VIS reach into IFR categories. Not ruling out lower categories
at this time with heavier areas of rain. Lower confidence in that
at this time though, so have only decreased categories to IFR. By
morning though, it is reasonable to believe we improve back to VFR
quickly as the dry slot of air gets pulled into the region before
the winds shift again but likely after or near the very end of the
forecast period as the low center passes nearly right over the
terminals. Have not included a wind shift veering all the way to
the WNW as a result and winds could vary in speed a bit during the
early morning hours as the change takes place.
&&
.TOP Watches/Warnings/Advisories...
Winter Weather Advisory from 6 PM this evening to 6 PM CST
Tuesday for KSZ010-011-021-022-034.
Winter Storm Warning from 6 PM this evening to midnight CST
Tuesday night for KSZ008-009-020.
&&
$$
SHORT TERM...Barjenbruch
LONG TERM...Bowen
AVIATION...Drake
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
222 PM CST MON FEB 1 2016
...updated discussion...
.DISCUSSION...
ISSUED AT 222 PM CST MON FEB 1 2016
A few items of concern within the next 24 hours. 1) snow, 2) thunderstorms,
3) wind. An upper level low will swing on in from the southwest through
the overnight. Considerable upslope is expected on the north side of
the synoptic disturbance. This region is generally across northwest
and north-central Kansas. For snow amounts, have the highest snow amounts
from Scott City to WaKeeney. 6-8" will be possible in this area. The
ECMWF shows slightly higher amounts, however, the mesoscale models are
lower as a result of low to mid level dry air advecting in. To the south
and southeast, have a wide area of advisory amounts (2-5") from Johnson
to Jetmore to Ash Valley and points northwest. Focusing farther south,
a modified warm sector will spread northward on the south side of the
low. HRRR and to a lesser extent the NAM show some MUCAPE forming. Low
level clouds have hung around across the OK/TX panhandles, but there
is some clearing this early afternoon. Models show -28C 500-hPa temperatures,
so I do think some MUCAPE can be realized if clearing/warming continues.
Forecast soundings are very impressive in terms of wind shear and kinematics.
Soundings support low topped convection. The HRRR is also showing some
updraft helicity, so there was a very slight concern for a brief spin
up tornado. Elkhart looks the most interesting in terms of any "spring-
like" convection. MUCAPE is weak, so this would be the main limiting
factor. Some of the other models like the ARW show somewhat of a line
developing across the Panhandles, so this might miss us, but still reasonably
confident there will be at least some thunderstorms around far southwest
Kansas this evening. Lastly, this system is forecast to be closed off
as it ejects across western Kansas. 850-hPa winds of 30-40 kt will spell
out the concern for windy conditions tomorrow morning. This will create
wind chills in the 5 to 15F range. Beyond tomorrow, the synoptic low
moves off to the northeast and weak high pressure with some downslope
moves in. Temperatures will rebound through the end of the business
week with 40s returning, except lower temps over the snow pack. Another
low may approach the region next Saturday, however, the main dynamics
look to be too far away from southwest Kansas. There might be a cooling
trend next week as the longwave trough amplifies and caa could develop
across the Central Plains.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Tuesday AFTERNOON)
ISSUED AT 1100 AM CST MON FEB 1 2016
Active aviation pd and generally not a good period for ga pilots. Have
added -tsra for KDDC this evening as the 500-hPa cold pool moves over.
Farther north, showers will eventually turn over to snow with KHYS seeing
the highest chance for blsn. Cigs will continue to deteriorate through
the day as the weather system moves through. Low stratus is likely in
its wake for the morning. Winds will pick up significantly too behind
the system - NW 20-35 kt.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 29 32 15 35 / 80 20 0 0
GCK 26 29 12 33 / 90 40 0 0
EHA 23 30 14 35 / 90 20 0 0
LBL 26 31 16 37 / 90 20 0 0
HYS 30 31 12 31 / 90 60 10 0
P28 35 39 19 38 / 60 20 0 0
&&
.DDC Watches/Warnings/Advisories...
Winter Weather Advisory from 6 PM CST /5 PM MST/ this evening to
6 PM CST /5 PM MST/ Tuesday for KSZ046-061>065-074>077.
Winter Storm Warning from 6 PM this evening to 6 PM CST Tuesday
for KSZ030-031-043>045.
&&
$$
Discussion...Sugden
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1238 PM EST MON FEB 1 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EST MON FEB 1 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW SPLIT FLOW ACROSS THE
CONUS. A POTENT LOOKING SRN STREAM SHORTWAVE IS MOVING ACROSS SRN
CA/SRN NV INTO AZ. THIS WAVE WILL QUICKLY MOVE E THEN NE...BRINGING
A WINTER STORM TO THE UPPER GREAT LAKES TUE AFTN THRU WED MORNING.
IN THE MEANTIME...THE UPPER LAKES ARE CURRENTLY UNDER BENIGN
CONFLUENT WESTERLY FLOW BTWN A TROF OVER CANADA ANCHORED BY MID
LEVEL LOW IN THE VCNTY OF HUDSON BAY AND SRN STREAM RIDGING OVER THE
SE STATES. WEAK SHORTWAVE AND A SFC TROF DROPPING S ACROSS LAKE
SUPERIOR INTO NRN UPPER MI HAS GENERATED SOME -SN OVERNIGHT ACROSS
PARTS OF THE NRN FCST AREA.
THE TODAY/TONIGHT PERIOD WILL GENERALLY BE QUIET. 850MB TEMPS WILL
GRADUALLY FALL TO MARGINAL LEVELS FOR LES OVER MAINLY CNTRL AND ERN
LAKE SUPERIOR. WITH SFC TROF THAT IS AIDING THE ONGOING PATCHY -SN
MOVING S AND GRADUALLY DISSIPATING...THERE MAY NOT BE MUCH TO
GENERATE -SHSN GIVEN THE MARGINAL AT BEST OVERWATER INSTABILITY. IN
ADDITION...THERE IS SOME CONCERN THAT A LITTLE -FZDZ COULD OCCUR
WITH MOISTURE DEPTH AT TIMES NOT REACHING THE -10C ISOTHERM...BUT
NOT SO SURE THERE WILL BE SUFFICIENT NEAR SATURATION AT THE LOWEST
LEVELS TO SUPPORT -FZDZ AS FCST SOUNDINGS SHOW A DECREASE IN RH BLO
1KFT. AT THIS POINT...AFTER SOME CHC POPS NEAR LAKE SUPERIOR EARLY
THIS MORNING...WILL HAVE NOTHING MORE THAN SCHC POPS FOR -SHSN THRU
THE AFTN. WINDS TEND TO SHIFT OFFSHORE TONIGHT...EXCEPT OVER THE
KEWEENAW. SO...OTHER THAN THE KEWEENAW...WILL GRADUALLY DROP SCHC
POPS TONIGHT. EXPECT MAX TEMPS TODAY MOSTLY IN THE UPPER 20S TO LWR
30S. LOWS TONIGHT WILL BE IN THE MID TEENS TO MID 20S. HOWEVER...
THERE IS SOME POTENTIAL THAT CLOUDS COULD CLEAR OUT FOR A WHILE IN
THE INTERIOR AS BIAS CORRECTED CANADIAN MODELS SHOW MINS DOWN INTO
THE SINGLE DIGITS ACROSS THE INTERIOR W HALF.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 746 AM EST MON FEB 1 2016
GENERAL SYNOPTIC...PHASING OF UPPER WAVES WILL CONTINUE TO
STRENGTHEN ROBUST SYSTEM APPROACHING THE FOUR CORNERS REGION RIGHT
NOW. EXPECT THE RESULT TO BE A MID 990S MB SFC LOW TO MOVE FROM NRN
IL AT 00Z WED TO NRN OR AT LEAST CENTRAL LOWER MI BY 12Z WED.
ALOFT...A CLOSED LOW WILL TRANSITION TO AN OPEN WAVE AS IT
ACCOMPANIES THE SFC LOW THROUGH THE REGION.
UNCERTAINTY...SIMILAR MODEL VARIABILITY TO WHAT WE WERE LOOKING AT
24 HOURS AGO...RELATIVELY SMALL DIFFERENCES IN TRACK AND TIMING
BETWEEN THE BULK OF GUIDANCE. THE MOST NOTABLE VARIANCE FROM THE
CONSENSUS IS THE NAM WHICH IS WEAKER AND FASTER WITH THE
SYSTEM...RESULTING IN SOMEWHAT LOWER SNOW TOTALS...ESPECIALLY OVER
NWRN UPPER MI. HOWEVER...THE NAM HAS BEEN STEADILY TRENDING TOWARD
THE MODEL CONSENSUS...AND CONTINUES TO DO SO WITH THE 06Z/01 RUN.
OTHERWISE...THE GFS AND ECMWF HAVE SHOWN A VERY SIMILAR TRACK FOR
THE LAST COUPLE OF DAYS. UNFORTUNATELY...WITH HOW FAST THIS SYSTEM
IS MOVING...THE CYCLONE DOES NOT REACH MATURE STAGE UNTIL IT KICKS
OUT E OF THE ROCKIES WED NIGHT...SO MODEL GUIDANCE WILL PROBABLY
CONTINUE TO BE SOMEWHAT VARIABLE UNTIL THEN. THAT BEING
SAID...PRETTY CONFIDENT IN SNOWFALL AMOUNTS REACHING WARNING
CRITERIA IN AREAS WHERE WATCHES WERE ISSUED TODAY. SREF MEAN AND
ENSEMBLE MEMBERS ALSO BACK THIS UP WITH GOOD CLUSTERING AND NO
MEMBERS THAT HAVE DRAMATICALLY LOW TOTALS.
SNOW AMOUNTS AND TIMING...EXPECT ALL PRECIP TO BE SNOW...ALTHOUGH
THERE IS AN OUTSIDE CHANCE OF A COUPLE OF HOURS OF FREEZING DRIZZLE
NEAR LAKE MI AS THE DRY SLOT MOVES THROUGH...BUT THAT WOULD BE
IMMEDIATELY AFTER THE SNOW FALLS SO ACCUMULATION ON ROADS WOULD NOT
BE AN ISSUE. CURRENT GUIDANCE SUGGESTS SNOW MOVES INTO THE MENOMINEE
AREA AROUND 18Z TUE AND MOVE N TO TO THE IRONWOOD-BARAGA-MARQUETTE-
NEWBERRY AREA BY SHORTLY AFTER 21Z...THEN COVERING THE REST OF THE
AREA BEFORE 00Z WED. SNOW WILL QUICKLY BECOME HEAVY AFTER IT
INITIATES...WITH THE HEAVIEST SNOW AND MOST OF THE SNOW FALLING
BEFORE MIDNIGHT-1AM TUE NIGHT IN MOST PLACES...HEAVY SNOW POTENTIAL
LASTING LONGER NEAR CENTRAL/ERN LAKE SUPERIOR. IN GENERAL HAVE 6-10
INCHES OVER THE CENTRAL AND E (UPGRADED THOSE AREAS TO WARNING) AND
UP TO 6 INCHES OVER THE W (ADVISORY). WITH MODELS COMING INTO BETTER
ALIGNMENT...POTENTIAL FOR HIGHER AMOUNTS (POSSIBLY MUCH HIGH) ARE
GOING TO HAVE TO BE FINE TUNED. FOR EXAMPLE THE LATE NAM-DNG RUN
PAINTS SIGNIFICANT HIGHER SNOWFALL OVER THE HIGHER TERRAIN OF THE
NCENTRAL. THAT IS VERY TRACK DEPENDENT...BUT THE POTENTIAL IS THERE.
SEE THE WSW FOR MORE DETAILS ON SNOWFALL AMOUNTS AND OTHER
ASSOCIATED HAZARDS (BLOWING SNOW).
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1237 PM EST MON FEB 1 2016
LOW LEVEL MOISTURE WILL LINGER ACROSS MUCH OF THE UPPER PENINSULA
THROUGH TONIGHT ALLOWING MVFR CEILINGS TO REMAIN IN PLACE. ANY
PRECIPIATION THAT OCCURS SHOULD BE FAIRLY LIGHT IN THE FORM OF
FLURRIES OR VERY LIGHT FREEZING DRIZZLE SLOWLY DIMINISHING THROUGH
THE DAY. VISIBILITY SHOULD NOT BE RESTRICTED DUE TO THE LIGHT
PRECIP. THERE MAY BE A BREIF PERIOD WHERE CEILINGS RISE TO VFR THIS
AFTERNOON...BUT THIS WILL BE FAIRLY SHORT-LIVED AS MVFR CEILINGS
WILL QUICKLY RETURN. THE NEXT PERIOD OF LOW CEILINGS AND VISIBILITY
WILL SLIDE IN LATE TUESDAY AFTERNOON JUST AFTER THIS TAF PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 507 AM EST MON FEB 1 2016
THE TUE NIGHT/WED TIME FRAME WILL BE THE MAIN PERIOD OF INTEREST FOR
STRONG WINDS ON LAKE SUPERIOR THIS WEEK AS LOW PRES TRACKS FROM THE
SRN PLAINS ACROSS FAR NORTHERN LWR MI. LOOKS LIKE THE LOW WILL
GENERATE A PERIOD OF NE TO N GALE FORCE WIND GUSTS LATE TUE NIGHT
THRU EARLY WED AFTN OVER ALL BUT FAR WRN LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING FROM 4 PM TUESDAY TO 4 PM EST WEDNESDAY FOR
MIZ004>007-085.
WINTER WEATHER ADVISORY FROM 4 PM EST /3 PM CST/ TUESDAY TO 7 AM
EST /6 AM CST/ WEDNESDAY FOR MIZ001>003-009-084.
WINTER STORM WARNING FROM 4 PM TUESDAY TO 1 PM EST WEDNESDAY FOR
MIZ013-014.
WINTER STORM WARNING FROM NOON TUESDAY TO 6 AM CST WEDNESDAY FOR
MIZ012.
WINTER STORM WARNING FROM 3 PM TUESDAY TO 6 AM CST WEDNESDAY FOR
MIZ010-011.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...KEC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1151 AM CST MON FEB 1 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 402 AM CST MON FEB 1 2016
CLEAR SKIES...LIGHT WINDS AND MOIST LOW LEVEL CONDITIONS FROM THE
MELTING ON SUNDAY HAS ALLOWED FOG TO FORM AT MOST LOCATIONS EARLY
THIS MORNING. PATCHY AREAS OF DENSE FOG ARE COMMON ONCE AGAIN THIS
MORNING ACROSS CENTRAL MN AND ALONG HIGHWAY 8 IN WEST CENTRAL WI.
HELPING TO ABATE THE FOG SOME IS AN INCREASE IN LOW CLOUDINESS FROM
NORTHERN AREAS OF THE STATE. THIS MASS OF LOW CEILINGS IS BEING
HANDLED FAIRLY WELL BY THE RAP AND NAM AT 875MB. THIS WOULD BRING
THE CLOUDS SOUTHEAST TODAY ALONG AND NORTH OF THE I-94 CORRIDOR.
HENCE...THE NORTHEAST HALF OF THE CWA WILL SEE THE MOST CLOUDINESS
TODAY WHILE THE SOUTHWEST HALF WILL SEE A GOOD DEAL OF SUNSHINE. IT
WILL BE ANOTHER MILD DAY WITH HIGHS FROM 30 TO 35 DEGREES.
THE MAIN FEATURE TONIGHT IS THE ONSET OF SNOW AHEAD OF THE WINTER
STORM OVER THE SOUTHWESTERN UNITED STATES EARLY THIS MORNING.
CURRENT THINKING IS THAT SNOW WILL OVERSPREAD THE I-90 CORRIDOR IN
THE 09Z-12Z TIME PERIOD WITH CATEGORICAL POPS IN PLACE. SNOW
ACCUMULATION IN THE THAT THREE HOUR WINDOW IS UP TO A HALF INCH. LOW
TEMPERATURES WERE RAISED A LITTLE BIT ACROSS SOUTHERN AREAS OF THE
FA WITH CLOUDINESS INCREASING FASTER WITH LOWS RANGING FROM THE
TEENS IN CENTRAL MN TO THE LOWER AND MIDDLE 20S TO THE SOUTH AND
EAST.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 402 AM CST MON FEB 1 2016
THE MAIN CONCERN IN THE LONG TERM PERIOD IS THE STRONG WINTER STORM
SET TO IMPACT THE UPPER MIDWEST TOMORROW INTO WEDNESDAY. AFTER THE
STORM MOVES THROUGH THE REGION...TEMPERATURES WILL RUN NEAR NORMAL
FOR EARLY FEBRUARY WITH A FEW CLIPPER SYSTEMS BRINGING POPS INTO THE
FORECAST TOWARD THE WEEKEND.
AS FOR THE LATEST INFORMATION ON THE APPROACHING WINTER
STORM...MODEL GUIDANCE CONTINUES TO WAFFLE BACK AND FORTH. THERE
HAD BEEN TWO DISTINCT CAMPS IN TERMS OF THE TRACK OF THE
STORM...WHICH STILL PERSISTED IN THE 00Z PRODUCT SUITE.
THE GFS HAS CONSISTENTLY BEEN ON THE NORTHERN SIDE OF THE VARIOUS
GUIDANCE. THE ECMWF LEANED TO THE NORTHERN ENVELOPE COMPARED TO THE
GEM AND THE NAM WHICH HAD A VERY SOUTHERN SOLUTION. THE 00Z RUN OF
THE NAM CAME IN WITH A SLIGHT NORTHWARD JOG...AS DID THE 06Z RUN.
THE 12Z EC YESTERDAY TOOK THE 0.5" QPF LINE INTO THE TWIN CITIES
METRO...BUT THEN DIALED IT BACK TO CLOSER TO 0.4" WITH THE 00Z RUN.
THE GFS HAS SLIGHTLY MORE QPF THAN THE LATEST EC. A FIRST LOOK AT
WHAT THE HI-RES ARW AND NMM INDICATE CAME IN OVERNIGHT...WITH
STARK DIFFERENCES AMONG THEM AS WELL. WHILE THE NMM INDICATED 0.48"
OF QPF FOR MSP...THE ARW INDICATED JUST 0.08". THE POINT IS...THERE
IS STILL UNCERTAINTY ALONG THE NORTHERN PERIPHERY OF THE HEAVY SNOW
SWATH...THERE WILL BE A TIGHT SNOWFALL GRADIENT AND IT WILL BE VERY
CLOSE TO THE TWIN CITIES METRO AREA. THIS IS WHY THE WATCH PRODUCTS
WERE LEFT IN PLACE FOR NOW. THE 12Z CYCLE OF MODEL GUIDANCE WILL
HOPEFULLY OFFER LESS UNCERTAINTY AND MORE CONFIDENCE TO NAIL DOWN
WHERE ANY WARNINGS NEED TO BE ISSUED. THE TUESDAY AFTERNOON COMMUTE
WILL BE HEAVILY IMPACTED BY THIS STORM.
OVERALL...THIS FORECAST LEANED TOWARD A BLEND OF THE ECMWF AND
GFS...SO SNOW AMOUNTS WERE GENERALLY TWEAKED UPWARD...AND A COUPLE OF
COUNTIES WERE ADDED TO THE WINTER STORM WATCH. AS FOR THE BLIZZARD
WATCH...DECIDED TO HOLD ON TO IT PRIMARILY DUE TO THE GUIDANCE
BACKING OFF SOME ON THE WINDS ACROSS SOUTH CENTRAL MN. ITS STILL
GOING TO BE BREEZY...BUT WE ARE NOT SURE IF BLIZZARD CRITERIA WILL BE
MET AT THIS TIME. THE WINDS LOOK STRONGER IN IOWA...WHICH EXPLAINS
WHY THEY WERE ABLE TO GO AHEAD WITH A BLIZZARD WARNING THERE. COULD
HAVE GONE WINTER STORM WARNING IN SOUTH CENTRAL MN...BUT DIDNT WANT
PEOPLE TO TAKE THEIR GUARD DOWN ABOUT THE POSSIBILITY OF TRUE
BLIZZARD LIKE CONDITIONS IN SOUTH CENTRAL MN. IF THE 12Z GUIDANCE
COMES IN WITH A SLIGHTLY DEEPER SURFACE LOW...TRUE BLIZZARD
CONDITIONS COULD BE REALIZED. REGARDLESS...TRAVEL ALONG THE I-90
CORRIDOR WILL BE TREACHEROUS TOMORROW WITH HEAVY SNOW AND THE
POTENTIAL FOR 6 TO 10 INCHES.
NOT MUCH IN TERMS OF PRECIPITATION IS EXPECTED BEYOND
TOMORROW...WITH TWO WAVES WORKING SOUTHEAST THROUGH CANADA THROUGH
THE END OF THE WEEK...BUT WOULD PRODUCE VERY LIGHT AMOUNTS OF SNOW.
OTHERWISE...SEASONABLE TEMPERATURES ARE EXPECTED...BUT THE ECMWF
DOES INDICATE THE ARCTIC AIR POURING SOUTH INTO OUR REGION EARLY
NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1151 AM CST MON FEB 1 2016
PATCHY FREEZING FOG AND AREAS OF LOW CIGS WILL PERSIST ACROSS OUR
AREA THROUGH THE AFTERNOON AND TONIGHT. IFR/LIFR CONDITIONS ARE
LIKELY IN AREAS OF FOG AND LOW CIGS...WHICH WILL LIKELY BECOME
MORE WIDESPREAD AFTER SUNSET THIS EVENING. TOMORROW MORNING...LOW
CIGS ARE STILL LIKELY BUT ATTENTION WILL SHIFT TO SNOW MOVING IN
FROM THE SOUTH. LIGHT SNOW WILL START ACROSS SOUTHERN MN AND PARTS
OF WEST CENTRAL WI AROUND 15Z...AND SNOWFALL RATES SHOULD INCREASE
BY 18Z. IFR VISIBILITY IS LIKELY BETWEEN 16Z-18Z FROM THE TWIN
CITIES SOUTH AS SNOW INTENSIFIES.
KMSP...A POCKET OF CLEAR SKIES IS CURRENTLY IN PLACE...BUT LOW
CLOUDS ARE LIKELY TO MOVE IN WITHIN A COUPLE HOURS THIS
AFTERNOON. IFR CIGS ARE POSSIBLE THROUGH THE EVENING UNDER THE LOW
CLOUD DECK...WITH PATCHY FOG/MIST ALSO POSSIBLE THROUGH THE
OVERNIGHT HOURS. LIGHT SNOW IS EXPECTED TO BEGIN AROUND 15Z
TUESDAY...AND WILL LIKELY INTENSIFY ENOUGH THAT IFR VISIBILITY IS
LIKELY BY 16Z-18Z. WINDS ON TUESDAY ARE EXPECTED TO BE FROM THE
NE AND INTENSIFY TO 15-20 KTS...WITH A FEW HIGHER GUSTS BY 18Z.
/OUTLOOK FOR KMSP/
TUE AFTN-NIGHT...IFR IN SN WITH CHC LIFR. WIND NNE 15-25 KTS.
WED...VFR. WIND NW 10-15 KTS.
THU...VFR. WIND SW 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
WIZ015-016-023>028.
WINTER WEATHER ADVISORY FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY
FOR WIZ014.
MN...WINTER STORM WARNING FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
MNZ060-062-063-067>070-075>078.
WINTER WEATHER ADVISORY FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY
FOR MNZ051>053-058-059-061-064>066.
BLIZZARD WARNING FROM 6 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
MNZ073-074-082>085-091>093.
&&
$$
SHORT TERM...RAH
LONG TERM...SPD
AVIATION...ADL
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
117 PM EST MON FEB 1 2016
.SYNOPSIS...
COLD FRONT PASSES TODAY BUT MILD AGAIN TUESDAY. STRONG SYSTEM MID
WEEK. A RETURN TO COLDER WEATHER FOLLOWS THAT SYSTEM TO END THE
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
11 AM UPDATE. NO SIGNIFICANT CHANGES.
COLD FRONT...CURRENTLY ALONG A LINE FROM ROUGHLY
CKB TO HTS...WILL MOVE THROUGH REST OF CWA TODAY...AND HAVE LIKELY
POPS WITH IT. PROGRESSION OF THE FRONT WILL SLOW TO A CRAWL THIS
EVENING ACROSS THE SOUTHERN MOUNTAINS AND COAL FIELDS...BUT DOES
LOOK TO PUSH ALL THE WAY THROUGH THE FORECAST AREA BY AROUND
MIDNIGHT...STALLING SOMEWHERE JUST SOUTH OF THE CWA.
USING A MIX OF THE HRRR AND LAMP...HAVE NON-DIURNAL TEMPERATURE
TRACE FOR TODAY...WITH GRADUALLY FALLING TEMPS BEHIND THE COLD
FRONT. MAY GET A BRIEF UPWARD BOUNCE IN SE OHIO LATE THIS
AFTERNOON IF THE CLOUDS CAN BREAK UP ENOUGH FOR SOME SUN.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
A WARM FRONT PUSHES NORTHWARD THROUGH THE AREA ON TUESDAY WITH
SOUTHERLY WINDS INCREASING. DUE TO RECENT MOS PERFORMANCE IN
SOUTHERLY WINDS...SIDED WITH THE WARMER GFS MOS.
MODELS THEN SHOW SHOWERS AND A COLD FRONT TUESDAY NIGHT INTO
WEDNESDAY. SOUNDINGS AND MOS GUIDANCE INDICATE THAT THUNDERSTORMS
ARE A POSSIBILITY. OF CONCERN IS A STRONG LOW LEVEL JET THAT
OVERLAPS THE INITIAL PRECIPITATION BAND. WORKING AGAINST THE WINDS
GETTING TO THE GROUND HOWEVER...ARE MODEL SOUNDINGS THAT SHOW AN
INVERSION. WILL NEED TO CONTINUE TO MONITOR THIS SITUATION
CLOSELY.
GFS AND ECMWF ARE THEN SHOWING 850 MB TEMPERATURES GETTING COLD
ENOUGH TO OVERTURN THE LOWER LEVELS AND POSSIBLY PRODUCE SOME LIGHT
SNOW OR FLURRIES FOR WEDNESDAY NIGHT INTO THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
ANY RESIDUAL WRAP AROUND RAIN SHOWERS IN THE WAKE OF A COLD FRONT
AND LARGE LOW PRESSURE SYSTEM SPEEDING NEWD AWAY FROM THE
AREA...WILL QUIT OVER THE LOWLANDS AND SWITCH TO UPSLOPE SNOW
SHOWERS OVER THE MOUNTAINS WED EVENING...AND THEN QUIT OVER THE
MOUNTAINS BY THU MORNING...AS LOW LEVEL NW FLOW BECOMES LIGHT
ANTICYCLONIC AHEAD OF HIGH PRESSURE APPROACHING FROM THE W.
THE HIGH MOVES ACROSS THE AREA FOR DRY...SEASONABLY CHILLY
WEATHER THU-SAT. THU DOES NOT LOOK TO PROMISE TOO MUCH
SUNSHINE...THOUGH...GIVEN LINGERING LOW LEVEL MOISTURE YIELDING
STRATOCU...AND HIGH CLOUD ASSOCIATED WITH A WAVE MOVING UP ALONG
THE FRONT THROUGH THE CAROLINAS.
MODELS ARE IN BETTER AGREEMENT ON THE NEXT COLD FRONT CROSSING THE
AREA ON SUNDAY...WITH ANY RAIN SHOWERS AHEAD OF IT SAT NT GOING TO
SOME SNOW SHOWERS OVERNIGHT AS THE FRONT CROSSES...A FEW SNOW
SHOWERS LINGERING ON SUNDAY IN ITS WAKE. THAT SAID...THE FRONT
LOOKS BARELY DISCERNIBLE IN THE ECMWF DEPICTION...AND THE MASS
FIELDS AS A WHOLE DIVERGE BY THEN. THIS LEADS TO UNCERTAINTY AS TO
THE TIMING OF THE NEXT SYSTEM APPROACHING AS EARLY AS THE END OF
DAY 7N NT...
WITH MODEL AGREEMENT THROUGH DAY 6...WPC GUIDANCE AND A BLEND OF
MODEL GUIDANCE WAS EMPLOYED FOR TEMPERATURES...NOT QUITE AS COLD
IN THE WAKE OF THE MID WEEK SYSTEM. LEANED MORE TOWARD THE COLDER GFS
DAY 7.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
18Z MONDAY THRU 18Z TUESDAY...
AT 18Z...COLD FRONT STRUGGLING TO EXIT MOUNTAINS...ALONG AN EKN-
BLF LINE...WITH MAIN BATCH OF RAIN EAST OF THAT LINE. FRONT WILL
BE SLOW TO SHIFT SOUTHEAST...BUT WILL EXIT SOUTHERN MOUNTAINS BY
00Z. BECAUSE OF THE SLOW DOWN...ANOTHER BATCH OF RAIN WILL MOVE
ACROSS THE SOUTHERN COAL FIELDS AND SOUTHERN MOUNTAINS 21-01Z.
GENERALLY MVFR CEILINGS WILL DOMINATE THRU MUCH OF THE
AFTERNOON EAST OF THE OHIO RIVER...WITH VFR CEILINGS SOUTHEAST
OHIO AND NORTHEAST KENTUCKY...AND IFR IN THE SOUTHERN MOUNTAINS.
AS WEAK HIGH PRESSURE BUILDS IN...CLEARING WILL WORK SOUTHEASTWARD
ACROSS MUCH OF OF THE AREA TONIGHT...EXCEPT REMAINING MVFR/IFR
SOUTHERN MOUNTAINS INCLUDING BKW. FOR FOG...WINDS DECREASE AND
TURN EASTERLY TONIGHT...AND WHERE SKIES CLEAR AND WINDS DECREASE
ENOUGH...WE CAN EXPECT RIVER VALLEY FOG AFTER 06Z...WITH IFR FOG
MAINLY AFFECTING CRW...EKN...AND AT BKW DUE TO NORTHERLY UPSLOPE
FLOW.
AFTER 14Z...GENERALLY MID AND HIGH CLOUDS AHEAD OF NEXT SYSTEM...BUT
SLOWER IMPROVEMENT SOUTHERN MOUNTAINS INCLUDING BKW AS WINDS WILL
BE SOUTHEAST UPSLOPE THERE. WITH THE HIGH PRESSURE CENTER ALREADY
SHIFTING EAST ACROSS NEW ENGLAND...A LOW PRESSURE SYSTEM WILL
APPROACH FROM THE WEST. THE BIGGEST FEATURE TUESDAY WILL BE THE
INCREASING SOUTHEAST WINDS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z TUESDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF MVFR/IFR CONDITIONS MAY VARY. FOG
COVERAGE AND INTENSITY QUESTIONABLE EARLY TUESDAY MORNING...OR
COULD BE MORE STRATUS THAN FOG.
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.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EST 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00
CRW CONSISTENCY M M M M M M M M M M H H
HTS CONSISTENCY M M M M M M M M M M H H
BKW CONSISTENCY L L L M M M M M M M M M
EKN CONSISTENCY M M M M M M M M M M M M
PKB CONSISTENCY M M M M M M M M M M H H
CKB CONSISTENCY M M M M M M M M M M M M
AFTER 18Z TUESDAY...
IFR POSSIBLE IN SHOWERS TUESDAY NIGHT INTO WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY/JMV/MZ
NEAR TERM...MZ
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1120 AM EST MON FEB 1 2016
.SYNOPSIS...
COLD FRONT PASSES TODAY BUT MILD AGAIN TUESDAY. STRONG SYSTEM MID
WEEK. A RETURN TO COLDER WEATHER FOLLOWS THAT SYSTEM TO END THE
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
11 AM UPDATE. NO SIGNIFICANT CHANGES.
COLD FRONT...CURRENTLY ALONG A LINE FROM ROUGHLY
CKB TO HTS...WILL MOVE THROUGH REST OF CWA TODAY...AND HAVE LIKELY
POPS WITH IT. PROGRESSION OF THE FRONT WILL SLOW TO A CRAWL THIS
EVENING ACROSS THE SOUTHERN MOUNTAINS AND COAL FIELDS...BUT DOES
LOOK TO PUSH ALL THE WAY THROUGH THE FORECAST AREA BY AROUND
MIDNIGHT...STALLING SOMEWHERE JUST SOUTH OF THE CWA.
USING A MIX OF THE HRRR AND LAMP...HAVE NON-DIURNAL TEMPERATURE
TRACE FOR TODAY...WITH GRADUALLY FALLING TEMPS BEHIND THE COLD
FRONT. MAY GET A BRIEF UPWARD BOUNCE IN SE OHIO LATE THIS
AFTERNOON IF THE CLOUDS CAN BREAK UP ENOUGH FOR SOME SUN.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
A WARM FRONT PUSHES NORTHWARD THROUGH THE AREA ON TUESDAY WITH
SOUTHERLY WINDS INCREASING. DUE TO RECENT MOS PERFORMANCE IN
SOUTHERLY WINDS...SIDED WITH THE WARMER GFS MOS.
MODELS THEN SHOW SHOWERS AND A COLD FRONT TUESDAY NIGHT INTO
WEDNESDAY. SOUNDINGS AND MOS GUIDANCE INDICATE THAT THUNDERSTORMS
ARE A POSSIBILITY. OF CONCERN IS A STRONG LOW LEVEL JET THAT
OVERLAPS THE INITIAL PRECIPITATION BAND. WORKING AGAINST THE WINDS
GETTING TO THE GROUND HOWEVER...ARE MODEL SOUNDINGS THAT SHOW AN
INVERSION. WILL NEED TO CONTINUE TO MONITOR THIS SITUATION
CLOSELY.
GFS AND ECMWF ARE THEN SHOWING 850 MB TEMPERATURES GETTING COLD
ENOUGH TO OVERTURN THE LOWER LEVELS AND POSSIBLY PRODUCE SOME LIGHT
SNOW OR FLURRIES FOR WEDNESDAY NIGHT INTO THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
ANY RESIDUAL WRAP AROUND RAIN SHOWERS IN THE WAKE OF A COLD FRONT
AND LARGE LOW PRESSURE SYSTEM SPEEDING NEWD AWAY FROM THE
AREA...WILL QUIT OVER THE LOWLANDS AND SWITCH TO UPSLOPE SNOW
SHOWERS OVER THE MOUNTAINS WED EVENING...AND THEN QUIT OVER THE
MOUNTAINS BY THU MORNING...AS LOW LEVEL NW FLOW BECOMES LIGHT
ANTICYCLONIC AHEAD OF HIGH PRESSURE APPROACHING FROM THE W.
THE HIGH MOVES ACROSS THE AREA FOR DRY...SEASONABLY CHILLY
WEATHER THU-SAT. THU DOES NOT LOOK TO PROMISE TOO MUCH
SUNSHINE...THOUGH...GIVEN LINGERING LOW LEVEL MOISTURE YIELDING
STRATOCU...AND HIGH CLOUD ASSOCIATED WITH A WAVE MOVING UP ALONG
THE FRONT THROUGH THE CAROLINAS.
MODELS ARE IN BETTER AGREEMENT ON THE NEXT COLD FRONT CROSSING THE
AREA ON SUNDAY...WITH ANY RAIN SHOWERS AHEAD OF IT SAT NT GOING TO
SOME SNOW SHOWERS OVERNIGHT AS THE FRONT CROSSES...A FEW SNOW
SHOWERS LINGERING ON SUNDAY IN ITS WAKE. THAT SAID...THE FRONT
LOOKS BARELY DISCERNIBLE IN THE ECMWF DEPICTION...AND THE MASS
FIELDS AS A WHOLE DIVERGE BY THEN. THIS LEADS TO UNCERTAINTY AS TO
THE TIMING OF THE NEXT SYSTEM APPROACHING AS EARLY AS THE END OF
DAY 7N NT...
WITH MODEL AGREEMENT THROUGH DAY 6...WPC GUIDANCE AND A BLEND OF
MODEL GUIDANCE WAS EMPLOYED FOR TEMPERATURES...NOT QUITE AS COLD
IN THE WAKE OF THE MID WEEK SYSTEM. LEANED MORE TOWARD THE COLDER GFS
DAY 7.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
15Z MONDAY THRU 12Z TUESDAY...
COLD FRONT INTO MOUNTAINS AT 15Z...WILL SLOW THIS EVENING AS IT
CONTINUES SOUTHEAST. MAIN BATCH OF RAIN LAGS SOMEWHAT BEHIND THE
FRONT...WILL WILL CLEAR THE MOUNTAINS BY 19Z. HOWEVER...BECAUSE OF
THE SLOW DOWN...ANOTHER BATCH OF RAIN WILL MOVE ACROSS THE
SOUTHERN COAL FIELDS AND SOUTHERN MOUNTAINS 21-01Z. DURING THIS
PERIOD...GENERALLY MVFR CEILINGS WILL DOMINATE THRU MUCH OF THE
AFTERNOON...WITH IFR IN THE SOUTHERN MOUNTAINS. THIS CLEARING
FROM MVFR CEILINGS WILL WORK EASTWARD ACROSS MUCH OF OF THE AREA
TONIGHT...EXCEPT REMAINING MVFR/IFR SOUTHERN MOUNTAINS INCLUDING
BKW. WINDS MAY REMAIN JUST STRONG ENOUGH TO KEEP FOG AT BAY
TONIGHT...OR CLOUDS MAY HANG TOUGH TO LOW CONFIDENCE ON FOG FOR
TONIGHT...FOR NOW OMITTING FOG MENTION LATER TONIGHT TIL NEW TAF
EVALUATION. NORTHERLY WINDS WILL BE LIGHT AND SWITCH TO EASTERLY
TONIGHT AS HIGH PRESSURE CENTER TO THE NORTHWEST QUICKLY MOVES
EAST INTO NEW ENGLAND.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z
TUESDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: TIMING OF MVFR/IFR CONDITIONS MAY VARY A
BIT. FOG QUESTIONABLE EARLY TUESDAY MORNING...OR COULD BE MORE
STRATUS THAN FOG.
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.
UTC 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03
EST 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22
CRW CONSISTENCY M M M M M M M M M M M M
HTS CONSISTENCY M M M M M M M M M M M M
BKW CONSISTENCY L L L L L M M M M M M M
EKN CONSISTENCY M M M M M M M M M M M M
PKB CONSISTENCY H H M M M M M M M M M M
CKB CONSISTENCY M M M M M M M M M M M M
AFTER 18Z TUESDAY...
IFR POSSIBLE IN SHOWERS TUESDAY NIGHT INTO WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY/JMV/MZ
NEAR TERM...JMV/MZ
SHORT TERM...RPY
LONG TERM...TRM
AVIATION...JMV/MZ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
451 PM EST MON FEB 1 2016
.SYNOPSIS...
A COLD FRONT WILL SETTLE SOUTH OF PENNSYLVANIA THIS
EVENING...THEN HIGH PRESSURE WILL BUILD IN FROM THE NORTH LATER
TONIGHT AND TUESDAY. LOW PRESSURE WILL TRACK WEST OF PENNSYLVANIA
DURING THE MIDDLE OF THE WEEK...PUSHING A TRAILING COLD FRONT
THROUGH THE AREA LATE WEDNESDAY. HIGH PRESSURE WILL BUILD OVER THE
REGION LATE NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE AREA OF LIGHT RAIN ASSOCIATED WITH A WEAK WAVE ON THE TRAILING
COLD FRONT IS CLIPPING MY SOUTHERN BORDER COUNTIES AS OF 21Z. HRRR TIMING
SUGGESTS THE LAST OF THE RAIN WILL EXIT LANCASTER CO BY ARND 7 PM.
HIGH PRES AND ASSOC DRIER AIR MASS WILL NOSE SOUTHWARD INTO THE
REGION OVERNIGHT...BRINGING CLEARING SKIES AND ALLOWING TEMPS TO
DROP BACK INTO THE 20S. BUT LOWS WILL STILL BE SOME 5-10 DEG
MILDER THAN NORMAL.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
OTHER THAN SOME MID AND HIGH CLOUDS DRIFTING OUT AHEAD OF THE
APPROACHING FRONTAL SYSTEM...TUESDAY WILL REMAIN FAIR AS HIGH
PRESSURE SLIDES EAST OF THE AREA.
HIGH TEMPS ARE EXPECTED IN THE 40S...TO NEAR 50F ACROSS SOME OF
THE HIGHER TERRAIN OF THE SOUTH.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE FLOW PATTERN IS FORECAST TO EVOLVE INTO A BROAD...LONGWAVE
TROF PATTERN IN THE SOUTHERN STREAM OVER THE FRONT RANGE OF THE
ROCKIES EARLY IN THIS WEEK. THE TROF IS FORECAST TO BE
PROGRESSIVE...AIDED BY AND RE-PHASING WITH NRN STREAM
ENERGY...CROSSING THE PLAINS MIDWEEK AND REACHING THE OH/TN
VALLEYS TOWARD THE END OF THE WEEK.
MODEL GUIDANCE SHOWS THINGS DRYING OUT MONDAY NIGHT INTO
TUESDAY...WITH FOCUS SHIFTING TO STRONG STORM SYSTEM EXPECTED TO
TRACK FROM THE FOUR CORNERS THROUGH THE PLAINS AND GREAT LAKES
INTO EASTERN CANADA. CENTRAL PA WILL REMAIN ON THE WARM SIDE OF
THIS DYNAMIC SYSTEM WITH ABOVE NORMAL TEMPS EXPECTED THROUGH
WEDNESDAY...WHICH WILL DRAMATICALLY REDUCE THE CURRENT SNOWPACK
OVER SOUTHERN MTNS AND SUSQ VALLEY.
MODEL BLENDS CONTINUE TO SUPPORT A STRONG SIGNAL FOR PRECIP ON
WEDNESDAY AND MAINTAINED HIGH POPS FOR THIS PERIOD. THE GUIDANCE
APPEARS TO BE FOCUSING A MOD-HVY RAINFALL AXIS ALONG AND TO THE
EAST OF THE APPALACHIANS WHICH SEEMS TIED TO STRONG H85 MSTR FLUX
ANOMS CENTERED WITHIN 40-50KT SWLY PRE-FRONTAL LOW LEVEL JET. THE
FRONTAL BAND PCPN COULD BE CONVECTIVELY ENHANCED WITH WARM SECTOR
PROGGED TO SURGE WELL INTO NEW ENGLAND. FCST MAX TEMPS ARE
CURRENTLY IN THE 48-58F RANGE WHICH COULD BE SUPPORTIVE OF SOME
MARGINAL INSTABILITY.
ALL GUIDANCE POINTS TOWARD A DECENT SHOT OF COLD AIR BEHIND THE
MIDWEEK SYSTEM STARTING THURSDAY /WITH A QUICK SHOT FOR SOME LAKE
EFFECT SNOW SHOWERS/ FOLLOWED BY A REINFORCING SHOT OF COLDER AIR
NEXT WEEKEND.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
POST FRONTAL CIGS REMAIN MVFR OVER THE HIGHER ELEVATIONS FROM THE
LAURELS NORTHWARD...WHILE MAINLY BROKEN CLOUDS BETWEEN
3000-10000` AFFECT THE REMAINING TERMINALS OF THE CENTRAL AND
EASTERN FLYING AREA. THERE IS ALSO A SMALL AREA OF VISIBILITIES IN
THE 3-5 MILE RANGE ASSOCIATED WITH A SMALL AREA OF LIGHT RAIN
TRACKING THROUGH THE LOWER SUSQ VALLEY. THE RAIN SHOULD TAPER OFF
BY EVENING WITH IMPROVING CONDITIONS AND A RETURN TO VFR AT ALL
SITES EXPECTED.
OUTLOOK...
TUE...VFR. RAIN/MVFR-IFR CIGS/LLWS DEVELOPING TUESDAY NIGHT.
WED...MVFR WITH POCKETS OF IFR. RAIN SHOWERS. LLWS. GUSTY WINDS
25+KT FROM 160-190 DEGREES SHIFTING TO 270-300 WED PM BEHIND THE
COLD FRONT.
THU...MVFR CIGS/SCT -SHSN WEST. VFR CENTRAL-EAST. LIGHTER WINDS.
FRI-SAT...NO SIG WX.
&&
.HYDROLOGY...
ISSUED A FLOOD WATCH FOR WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON.
LATEST MODEL ENSEMBLE RIVER FORECASTS CONTINUE TO INDICATE
POTENTIAL RISK FOR SMALL STREAM FLOODING ACROSS SOUTH CENTRAL AND
SOUTHEAST PA WEDNESDAY INTO THURSDAY/FEBRUARY 3-4. MARFC IS
HIGHLIGHTING THIS THREAT IN THEIR SIGNIFICANT FLOOD OUTLOOK. THE
MAIN AREA OF CONCERN AT THIS TIME IS ACROSS THE JUNIATA AND LOWER
MAIN STEM SUSQUEHANNA BASINS. THE FLOOD RISK WILL BE A COMBINATION
OF SNOWMELT/SATURATED GROUND AND FORECAST MODERATE TO LOCALLY
HEAVY RAINFALL.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON FOR PAZ056-057-059-063>066.
&&
$$
SYNOPSIS...LA CORTE/FITZGERALD
NEAR TERM...FITZGERALD/LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
403 PM EST MON FEB 1 2016
.SYNOPSIS...
A COLD FRONT WILL SETTLE SOUTH OF THE AREA LATER TODAY AND
OVERNIGHT. LOW PRESSURE WILL TRACK WEST OF PENNSYLVANIA DURING
THE MIDDLE OF THE WEEK...PUSHING A TRAILING COLD FRONT THROUGH THE
AREA LATE WEDNESDAY. HIGH PRESSURE WILL BUILD OVER THE REGION LATE
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE AREA OF LIGHT RAIN ASSOCIATED WITH A WEAK WAVE ON THE TRAILING
COLD FRONT IS CLIPPING MY SOUTHERN BORDER COUNTIES...AS EARLIER
ADVERTISED BY THE HRRR AND RAP. THE TIMING SUGGESTS THE RAIN
TAPERING OFF BETWEEN ABOUT 3 AND 6 PM WITH GENERAL DRYING SETTING
IN AS HIGH PRESSURE NOSES IN FROM THE GREAT LAKES.
OTHERWISE MOST OF THE REGION WILL REMAIN DRY INTO THE OVERNIGHT.
CLOUDS WILL SCATTER OUT OVERNIGHT UNDER INCREASING HIGH PRESSURE
ALLOWING TEMPS TO DROP BACK INTO THE 20S. BUT LOWS WILL STILL BE
SOME 5-10 DEG MILDER THAN NORMAL.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
OTHER THAN SOME MID AND HIGH CLOUDS DRIFTING OUT AHEAD OF THE
APPROACHING FRONTAL SYSTEM...TUESDAY WILL REMAIN FAIR AS HIGH
PRESSURE SLIDES EAST OF THE AREA.
HIGH TEMPS ARE EXPECTED IN THE 40S...TO NEAR 50F ACROSS SOME OF
THE HIGHER TERRAIN OF THE SOUTH.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE FLOW PATTERN IS FORECAST TO EVOLVE INTO A BROAD...LONGWAVE
TROF PATTERN IN THE SOUTHERN STREAM OVER THE FRONT RANGE OF THE
ROCKIES EARLY IN THIS WEEK. THE TROF IS FORECAST TO BE
PROGRESSIVE...AIDED BY AND RE-PHASING WITH NRN STREAM
ENERGY...CROSSING THE PLAINS MIDWEEK AND REACHING THE OH/TN
VALLEYS TOWARD THE END OF THE WEEK.
MODEL GUIDANCE SHOWS THINGS DRYING OUT MONDAY NIGHT INTO
TUESDAY...WITH FOCUS SHIFTING TO STRONG STORM SYSTEM EXPECTED TO
TRACK FROM THE FOUR CORNERS THROUGH THE PLAINS AND GREAT LAKES
INTO EASTERN CANADA. CENTRAL PA WILL REMAIN ON THE WARM SIDE OF
THIS DYNAMIC SYSTEM WITH ABOVE NORMAL TEMPS EXPECTED THROUGH
WEDNESDAY...WHICH WILL DRAMATICALLY REDUCE THE CURRENT SNOWPACK
OVER SOUTHERN MTNS AND SUSQ VALLEY.
MODEL BLENDS CONTINUE TO SUPPORT A STRONG SIGNAL FOR PRECIP ON
WEDNESDAY AND MAINTAINED HIGH POPS FOR THIS PERIOD. THE GUIDANCE
APPEARS TO BE FOCUSING A MOD-HVY RAINFALL AXIS ALONG AND TO THE
EAST OF THE APPALACHIANS WHICH SEEMS TIED TO STRONG H85 MSTR FLUX
ANOMS CENTERED WITHIN 40-50KT SWLY PRE-FRONTAL LOW LEVEL JET. THE
FRONTAL BAND PCPN COULD BE CONVECTIVELY ENHANCED WITH WARM SECTOR
PROGGED TO SURGE WELL INTO NEW ENGLAND. FCST MAX TEMPS ARE
CURRENTLY IN THE 48-58F RANGE WHICH COULD BE SUPPORTIVE OF SOME
MARGINAL INSTABILITY.
ALL GUIDANCE POINTS TOWARD A DECENT SHOT OF COLD AIR BEHIND THE
MIDWEEK SYSTEM STARTING THURSDAY /WITH A QUICK SHOT FOR SOME LAKE
EFFECT SNOW SHOWERS/ FOLLOWED BY A REINFORCING SHOT OF COLDER AIR
NEXT WEEKEND.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
POST FRONTAL CIGS REMAIN MVFR OVER THE HIGHER ELEVATIONS FROM THE
LAURELS NORTHWARD...WHILE MAINLY BROKEN CLOUDS BETWEEN
3000-10000` AFFECT THE REMAINING TERMINALS OF THE CENTRAL AND
EASTERN FLYING AREA. THERE IS ALSO A SMALL AREA OF VISIBILITIES IN
THE 3-5 MILE RANGE ASSOCIATED WITH A SMALL AREA OF LIGHT RAIN
TRACKING THROUGH THE LOWER SUSQ VALLEY. THE RAIN SHOULD TAPER OFF
BY EVENING WITH IMPROVING CONDITIONS AND A RETURN TO VFR AT ALL
SITES EXPECTED.
OUTLOOK...
TUE...VFR. RAIN/MVFR-IFR CIGS/LLWS DEVELOPING TUESDAY NIGHT.
WED...MVFR WITH POCKETS OF IFR. RAIN SHOWERS. LLWS. GUSTY WINDS
25+KT FROM 160-190 DEGREES SHIFTING TO 270-300 WED PM BEHIND THE
COLD FRONT.
THU...MVFR CIGS/SCT -SHSN WEST. VFR CENTRAL-EAST. LIGHTER WINDS.
FRI-SAT...NO SIG WX.
&&
.HYDROLOGY...
ISSUED A FLOOD WATCH FOR WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON.
LATEST MODEL ENSEMBLE RIVER FORECASTS CONTINUE TO INDICATE
POTENTIAL RISK FOR SMALL STREAM FLOODING ACROSS SOUTH CENTRAL AND
SOUTHEAST PA WEDNESDAY INTO THURSDAY/FEBRUARY 3-4. MARFC IS
HIGHLIGHTING THIS THREAT IN THEIR SIGNIFICANT FLOOD OUTLOOK. THE
MAIN AREA OF CONCERN AT THIS TIME IS ACROSS THE JUNIATA AND LOWER
MAIN STEM SUSQUEHANNA BASINS. THE FLOOD RISK WILL BE A COMBINATION
OF SNOWMELT/SATURATED GROUND AND FORECAST MODERATE TO LOCALLY
HEAVY RAINFALL.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON FOR PAZ056-057-059-063>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
217 PM EST MON FEB 1 2016
.SYNOPSIS...
A COLD FRONT WILL SETTLE SOUTH OF THE AREA LATER TODAY AND
OVERNIGHT. LOW PRESSURE WILL TRACK WEST OF PENNSYLVANIA DURING
THE MIDDLE OF THE WEEK...PUSHING A TRAILING COLD FRONT THROUGH THE
AREA LATE WEDNESDAY. HIGH PRESSURE WILL BUILD OVER THE REGION LATE
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE AREA OF LIGHT RAIN ASSOCIATED WITH A WEAK WAVE ON THE TRAILING
COLD FRONT IS CLIPPING MY SOUTHERN BORDER COUNTIES...AS EARLIER
ADVERTISED BY THE HRRR AND RAP. THE TIMING SUGGESTS THE RAIN
TAPERING OFF BETWEEN ABOUT 3 AND 6 PM WITH GENERAL DRYING SETTING
IN AS HIGH PRESSURE NOSES IN FROM THE GREAT LAKES.
OTHERWISE MOST OF THE REGION WILL REMAIN DRY INTO THE OVERNIGHT.
CLOUDS WILL SCATTER OUT OVERNIGHT UNDER INCREASING HIGH PRESSURE
ALLOWING TEMPS TO DROP BACK INTO THE 20S. BUT LOWS WILL STILL BE
SOME 5-10 DEG MILDER THAN NORMAL.
&&
.SHORT TERM /TUESDAY/...
OTHER THAN SOME MID AND HIGH CLOUDS DRIFTING OUT AHEAD OF THE
APPROACHING FRONTAL SYSTEM...TUESDAY WILL REMAIN FAIR AS HIGH
PRESSURE SLIDES EAST OF THE AREA.
HIGH TEMPS ARE EXPECTED IN THE 40S...TO NEAR 50F ACROSS SOME OF
THE HIGHER TERRAIN OF THE SOUTH.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
EXPANSIVE ZONAL FLOW PATTERN...COMBINING THE NORTHERN AND
SOUTHERN STREAMS OF THE MAIN JET...STRETCHES FROM COAST TO COAST
THIS WEEKEND. THE FLOW PATTERN IS FORECAST TO EVOLVE INTO A
BROAD...LONGWAVE TROF PATTERN IN THE SOUTHERN STREAM OVER THE
FRONT RANGE OF THE ROCKIES EARLY IN THE WEEK. THE TROF IS FORECAST
TO BE PROGRESSIVE...AIDED BY AND RE-PHASING WITH NRN STREAM
ENERGY...CROSSING THE PLAINS MIDWEEK AND REACHING THE OH/TN
VALLEYS TOWARD THE END OF THE WEEK.
MODEL GUIDANCE SHOWS THINGS DRYING OUT MONDAY NIGHT INTO
TUESDAY...WITH FOCUS SHIFTING TO STRONG STORM SYSTEM EXPECTED TO
TRACK FROM THE FOUR CORNERS THROUGH THE PLAINS AND GREAT LAKES
INTO EASTERN CANADA. CENTRAL PA WILL REMAIN ON THE WARM SIDE OF
THIS DYNAMIC SYSTEM WITH ABOVE NORMAL TEMPS EXPECTED THROUGH
WEDNESDAY...WHICH WILL DRAMATICALLY REDUCE THE CURRENT SNOWPACK
OVER SOUTHERN MTNS AND SUSQ VALLEY.
MODEL BLENDS CONTINUE TO SUPPORT A STRONG SIGNAL FOR PRECIP ON
WEDNESDAY AND MAINTAINED HIGH POPS FOR THIS PERIOD. THE GUIDANCE
APPEARS TO BE FOCUSING A MOD-HVY RAINFALL AXIS ALONG AND TO THE
EAST OF THE APPALACHIANS WHICH SEEMS TIED TO STRONG H85 MSTR FLUX
ANOMS CENTERED WITHIN 40-50KT SWLY PRE-FRONTAL LOW LEVEL JET. THE
FRONTAL BAND PCPN COULD BE CONVECTIVELY ENHANCED WITH WARM SECTOR
PROGGED TO SURGE WELL INTO NEW ENGLAND. FCST MAX TEMPS ARE
CURRENTLY IN THE 48-58F RANGE WHICH COULD BE SUPPORTIVE OF SOME
MARGINAL INSTABILITY.
ALL GUIDANCE POINTS TOWARD A DECENT SHOT OF COLD AIR BEHIND THE
MIDWEEK SYSTEM STARTING THURSDAY /WITH A QUICK SHOT FOR SOME LAKE
EFFECT SNOW SHOWERS/ FOLLOWED BY A REINFORCING SHOT OF COLDER AIR
NEXT WEEKEND.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
POST FRONTAL CIGS REMAIN MVFR OVER THE HIGHER ELEVATIONS FROM THE
LAURELS NORTHWARD...WHILE MAINLY BROKEN CLOUDS BETWEEN
3000-10000` AFFECT THE REMAINING TERMINALS OF THE CENTRAL AND
EASTERN FLYING AREA. THERE IS ALSO A SMALL AREA OF VISIBILITIES IN
THE 3-5 MILE RANGE ASSOCIATED WITH A SMALL AREA OF LIGHT RAIN
TRACKING THROUGH THE LOWER SUSQ VALLEY. THE RAIN SHOULD TAPER OFF
BY EVENING WITH IMPROVING CONDITIONS AND A RETURN TO VFR AT ALL
SITES EXPECTED.
OUTLOOK...
TUE...VFR. RAIN/MVFR-IFR CIGS/LLWS DEVELOPING TUESDAY NIGHT.
WED...MVFR WITH POCKETS OF IFR. RAIN SHOWERS. LLWS. GUSTY WINDS
25+KT FROM 160-190 DEGREES SHIFTING TO 270-300 WED PM BEHIND THE
COLD FRONT.
THU...MVFR CIGS/SCT -SHSN WEST. VFR CENTRAL-EAST. LIGHTER WINDS.
FRI-SAT...NO SIG WX.
&&
.HYDROLOGY...
ISSUED A FLOOD WATCH FOR WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON.
LATEST MODEL ENSEMBLE RIVER FORECASTS CONTINUE TO INDICATE
POTENTIAL RISK FOR SMALL STREAM FLOODING ACROSS SOUTH CENTRAL AND
SOUTHEAST PA WEDNESDAY INTO THURSDAY/FEBRUARY 3-4. MARFC IS
HIGHLIGHTING THIS THREAT IN THEIR SIGNIFICANT FLOOD OUTLOOK. THE
MAIN AREA OF CONCERN AT THIS TIME IS ACROSS THE JUNIATA AND LOWER
MAIN STEM SUSQUEHANNA BASINS. THE FLOOD RISK WILL BE A COMBINATION
OF SNOWMELT/SATURATED GROUND AND FORECAST MODERATE TO LOCALLY
HEAVY RAINFALL.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON FOR PAZ056-057-059-063>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE
HYDROLOGY...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
147 PM EST MON FEB 1 2016
.SYNOPSIS...
A COLD FRONT WILL SETTLE SOUTH OF THE AREA LATER TODAY AND
OVERNIGHT. LOW PRESSURE WILL TRACK WEST OF PENNSYLVANIA DURING
THE MIDDLE OF THE WEEK...PUSHING A TRAILING COLD FRONT THROUGH THE
AREA LATE WEDNESDAY. HIGH PRESSURE WILL BUILD OVER THE REGION LATE
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE AREA OF LIGHT RAIN ASSOCIATED WITH A WEAK WAVE ON THE TRAILING
COLD FRONT IS CLIPPING MY SOUTHERN BORDER COUNTIES...AS EARLIER
ADVERTISED BY THE HRRR AND RAP. THE TIMING SUGGESTS THE RAIN
TAPERING OFF BETWEEN ABOUT 3 AND 6 PM WITH GENERAL DRYING SETTING
IN AS HIGH PRESSURE NOSES IN FROM THE GREAT LAKES.
OTHERWISE MOST OF THE REGION WILL REMAIN DRY INTO THE OVERNIGHT.
CLOUDS WILL SCATTER OUT OVERNIGHT UNDER INCREASING HIGH PRESSURE
ALLOWING TEMPS TO DROP BACK INTO THE 20S. BUT LOWS WILL STILL BE
SOME 5-10 DEG MILDER THAN NORMAL.
&&
.SHORT TERM /TUESDAY/...
OTHER THAN SOME MID AND HIGH CLOUDS DRIFTING OUT AHEAD OF THE
APPROACHING FRONTAL SYSTEM...TUESDAY WILL REMAIN FAIR AS HIGH
PRESSURE SLIDES EAST OF THE AREA.
HIGH TEMPS ARE EXPECTED IN THE 40S...TO NEAR 50F ACROSS SOME OF
THE HIGHER TERRAIN OF THE SOUTH.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
EXPANSIVE ZONAL FLOW PATTERN...COMBINING THE NORTHERN AND
SOUTHERN STREAMS OF THE MAIN JET...STRETCHES FROM COAST TO COAST
THIS WEEKEND. THE FLOW PATTERN IS FORECAST TO EVOLVE INTO A
BROAD...LONGWAVE TROF PATTERN IN THE SOUTHERN STREAM OVER THE
FRONT RANGE OF THE ROCKIES EARLY IN THE WEEK. THE TROF IS FORECAST
TO BE PROGRESSIVE...AIDED BY AND RE-PHASING WITH NRN STREAM
ENERGY...CROSSING THE PLAINS MIDWEEK AND REACHING THE OH/TN
VALLEYS TOWARD THE END OF THE WEEK.
MODEL GUIDANCE SHOWS THINGS DRYING OUT MONDAY NIGHT INTO
TUESDAY...WITH FOCUS SHIFTING TO STRONG STORM SYSTEM EXPECTED TO
TRACK FROM THE FOUR CORNERS THROUGH THE PLAINS AND GREAT LAKES
INTO EASTERN CANADA. CENTRAL PA WILL REMAIN ON THE WARM SIDE OF
THIS DYNAMIC SYSTEM WITH ABOVE NORMAL TEMPS EXPECTED THROUGH
WEDNESDAY...WHICH WILL DRAMATICALLY REDUCE THE CURRENT SNOWPACK
OVER SOUTHERN MTNS AND SUSQ VALLEY.
MODEL BLENDS CONTINUE TO SUPPORT A STRONG SIGNAL FOR PRECIP ON
WEDNESDAY AND MAINTAINED HIGH POPS FOR THIS PERIOD. THE GUIDANCE
APPEARS TO BE FOCUSING A MOD-HVY RAINFALL AXIS ALONG AND TO THE
EAST OF THE APPALACHIANS WHICH SEEMS TIED TO STRONG H85 MSTR FLUX
ANOMS CENTERED WITHIN 40-50KT SWLY PRE-FRONTAL LOW LEVEL JET. THE
FRONTAL BAND PCPN COULD BE CONVECTIVELY ENHANCED WITH WARM SECTOR
PROGGED TO SURGE WELL INTO NEW ENGLAND. FCST MAX TEMPS ARE
CURRENTLY IN THE 48-58F RANGE WHICH COULD BE SUPPORTIVE OF SOME
MARGINAL INSTABILITY.
ALL GUIDANCE POINTS TOWARD A DECENT SHOT OF COLD AIR BEHIND THE
MIDWEEK SYSTEM STARTING THURSDAY /WITH A QUICK SHOT FOR SOME LAKE
EFFECT SNOW SHOWERS/ FOLLOWED BY A REINFORCING SHOT OF COLDER AIR
NEXT WEEKEND.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
POST FRONTAL CIGS REMAIN MVFR OVER THE HIGHER ELEVATIONS FROM THE
LAURELS NORTHWARD...WHILE MAINLY BROKEN CLOUDS BETWEEN
3000-10000` AFFECT THE REMAINING TERMINALS OF THE CENTRAL AND
EASTERN FLYING AREA. THERE IS ALSO A SMALL AREA OF VISIBILITIES IN
THE 3-5 MILE RANGE ASSOCIATED WITH A SMALL AREA OF LIGHT RAIN
TRACKING THROUGH THE LOWER SUSQ VALLEY. THE RAIN SHOULD TAPER OFF
BY EVENING WITH IMPROVING CONDITIONS AND A RETURN TO VFR AT ALL
SITES EXPECTED.
OUTLOOK...
TUE...VFR. RAIN/MVFR-IFR CIGS/LLWS DEVELOPING TUESDAY NIGHT.
WED...MVFR WITH POCKETS OF IFR. RAIN SHOWERS. LLWS. GUSTY WINDS
25+KT FROM 160-190 DEGREES SHIFTING TO 270-300 WED PM BEHIND THE
COLD FRONT.
THU...MVFR CIGS/SCT -SHSN WEST. VFR CENTRAL-EAST. LIGHTER WINDS.
FRI-SAT...NO SIG WX.
&&
.HYDROLOGY...
LATEST MODEL ENSEMBLE RIVER FORECASTS /MIFFS/ CONTINUE TO
INDICATE POTENTIAL RISK FOR SMALL STREAM FLOODING ACROSS SOUTH
CENTRAL AND SOUTHEAST PA WEDNESDAY INTO THURSDAY/FEBRUARY 3-4.
MARFC IS HIGHLIGHTING THIS THREAT IN THEIR SIGNIFICANT FLOOD
OUTLOOK. THE MAIN AREA OF CONCERN AT THIS TIME IS ACROSS THE
JUNIATA AND LOWER MAIN STEM SUSQUEHANNA BASINS. THE FLOOD RISK
WILL BE A COMBINATION OF SNOWMELT/SATURATED GROUND AND FORECAST
MODERATE TO LOCALLY HEAVY RAINFALL. WE ARE ASSESSING THE FLOOD
POTENTIAL AND MAY CONSIDER ISSUING A FLOOD WATCH LATER TODAY.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1118 AM EST MON FEB 1 2016
.SYNOPSIS...
A COLD FRONT WILL SETTLE SOUTH OF THE AREA THIS AFTERNOON. LOW
PRESSURE WILL TRACK WEST OF PENNSYLVANIA DURING THE MIDDLE OF THE
WEEK...PUSHING A TRAILING COLD FRONT THROUGH THE AREA LATE
WEDNESDAY. HIGH PRESSURE WILL BUILD OVER THE REGION LATE NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MESO ANAL INDICATES THE COLD FRONT HAS CLEARED LANCASTER COUNTY
WITH A NW FLOW DEVELOPING IN ITS WAKE.
BIGGEST CONCERN IS THE POTENTIAL FOR A WEAK WAVE TO FORM ON THE
TRAILING COLD FRONT AND CAUSE AN AREA OF LIGHT RAIN TO REDEVELOP
OVER MY FAR SRN COUNTIES ALONG THE MASON-DIXON LINE. THE HRRR AND
SREF ARE PRETTY AGGRESSIVE WITH THIS SO I TRIED TO PAINT THE
CHANCE OF RAINS MOVING BACK IN FOR A FEW HOURS THIS AFTERNOON. I
MAY YET BE TOO LOW WITH THE POPS AND WILL HAVE TO ADJUST AS IT
BECOMES CLEARER WHETHER THE AREA OF RAIN CURRENTLY TRACKING
THROUGH WEST VA SLIDES DUE EAST STAYING SOUTH OF THE BORDER OR
NUDGES JUST A LITTLE NORTH AND AFFECTS THE BORDER COUNTIES.
OTHERWISE...THE PM HOURS SHOULD BE MAINLY DRY WITH A MIX OF SUN
AND CLOUDS DEVELOPING ACROSS MUCH OF CENTRAL AND NW PA...AS DRIER
AIR AND HIGH PRESSURE BUILD INTO THE AREA.
TEMPS WEIGHTED ABOUT 75 PERCENT TWD NEW CONSENSUS BLENDED MODEL
GUIDANCE YIELD HIGHS IN THE 40S TODAY...SEVERAL DEG COOLER THAN
SUNDAY IN MOST LOCATIONS. EVEN GIVEN THE COOLER READINGS...THE
HIGH TEMPS WILL STILL AVERAGE SOME 5-10 DEG WARMER THAN NORMAL FOR
THE FIRST DAY OF FEBRUARY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
HIGH PRESSURE RIDGE WILL SLIDE EAST ACROSS THE STATE TONIGHT INTO
TUESDAY...BRINGING FAIR WEATHER WITH A LIGHT NORTHWEST-NE
BREEZE. EXPECT JUST SOME SCATTERED ALTO CU AND CIRRUS CLOUDS
SPREADING OVER THE RIDGE TONIGHT AND TUESDAY MORNING. LOW TEMPS
WILL RANGE FROM 25-30F /;WHICH IS ABOUT 5-10F WARMER THAN NORMAL
ACROSS THE CENTRAL AND EASTERN VALLEY LOCATIONS...AND ABOUT 15 DEG
F ABOVE NORMAL ACROSS THE WESTERN MTNS.
THE SOUTHEAST TO SOUTHERLY LLVL FLOW WILL STRENGTHEN LATER TUESDAY
AND TUESDAY NIGHT...AND WILL HELP TO ADVECT THICKENING MULTI-
LAYERED CLOUDS ACROSS THE REGION.
LATEST BLENDED MULTI-MODEL GUIDANCE AND THE TIMING OF THE HIGH`S
DEPARTURE OFF THE MID ATLANTIC AND NEW ENGLAND COASTS TUESDAY AND
INCREASING AFTERNOON CLOUDS SHOULD YIELD A HIGH TEMP IN THE
40S...TO NEAR 50F ACROSS SOME OF THE HIGHER TERRAIN OF THE SOUTH
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
EXPANSIVE ZONAL FLOW PATTERN...COMBINING THE NORTHERN AND
SOUTHERN STREAMS OF THE MAIN JET...STRETCHES FROM COAST TO COAST
THIS WEEKEND. THE FLOW PATTERN IS FORECAST TO EVOLVE INTO A
BROAD...LONGWAVE TROF PATTERN IN THE SOUTHERN STREAM OVER THE
FRONT RANGE OF THE ROCKIES EARLY IN THE WEEK. THE TROF IS FORECAST
TO BE PROGRESSIVE...AIDED BY AND RE-PHASING WITH NRN STREAM
ENERGY...CROSSING THE PLAINS MIDWEEK AND REACHING THE OH/TN
VALLEYS TOWARD THE END OF THE WEEK.
MODEL GUIDANCE SHOWS THINGS DRYING OUT MONDAY NIGHT INTO
TUESDAY...WITH FOCUS SHIFTING TO STRONG STORM SYSTEM EXPECTED TO
TRACK FROM THE FOUR CORNERS THROUGH THE PLAINS AND GREAT LAKES
INTO EASTERN CANADA. CENTRAL PA WILL REMAIN ON THE WARM SIDE OF
THIS DYNAMIC SYSTEM WITH ABOVE NORMAL TEMPS EXPECTED THROUGH
WEDNESDAY...WHICH WILL DRAMATICALLY REDUCE THE CURRENT SNOWPACK
OVER SOUTHERN MTNS AND SUSQ VALLEY.
MODEL BLENDS CONTINUE TO SUPPORT A STRONG SIGNAL FOR PRECIP ON
WEDNESDAY AND MAINTAINED HIGH POPS FOR THIS PERIOD. THE GUIDANCE
APPEARS TO BE FOCUSING A MOD-HVY RAINFALL AXIS ALONG AND TO THE
EAST OF THE APPALACHIANS WHICH SEEMS TIED TO STRONG H85 MSTR FLUX
ANOMS CENTERED WITHIN 40-50KT SWLY PRE-FRONTAL LOW LEVEL JET. THE
FRONTAL BAND PCPN COULD BE CONVECTIVELY ENHANCED WITH WARM SECTOR
PROGGED TO SURGE WELL INTO NEW ENGLAND. FCST MAX TEMPS ARE
CURRENTLY IN THE 48-58F RANGE WHICH COULD BE SUPPORTIVE OF SOME
MARGINAL INSTABILITY.
ALL GUIDANCE POINTS TOWARD A DECENT SHOT OF COLD AIR BEHIND THE
MIDWEEK SYSTEM STARTING THURSDAY /WITH A QUICK SHOT FOR SOME LAKE
EFFECT SNOW SHOWERS/ FOLLOWED BY A REINFORCING SHOT OF COLDER AIR
NEXT WEEKEND.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
POST FRONTAL CIGS REMAIN MVFR OVER THE HIGHER ELEVATIONS FROM THE
LAURELS NORTHWARD...WHILE MAINLY BROKEN CLOUDS BETWEEN
3000-10000` AFFECT THE REMAINING TERMINALS OF THE CENTRAL AND
EASTERN FLYING AREA.
IMPROVING CONDITIONS CAN BE EXPECTED BY THIS EVE WITH RETURN TO
VFR AT ALL SITES.
OUTLOOK...
TUE...VFR. RAIN/MVFR-IFR CIGS/LLWS DEVELOPING TUESDAY NIGHT.
WED...MVFR WITH POCKETS OF IFR. RAIN SHOWERS. LLWS. GUSTY WINDS
25+KT FROM 160-190 DEGREES SHIFTING TO 270-300 WED PM BEHIND THE
COLD FRONT.
THU...MVFR CIGS/SCT -SHSN WEST. VFR CENTRAL-EAST. LIGHTER WINDS.
FRI...NO SIG WX.
&&
.HYDROLOGY...
LATEST MODEL ENSEMBLE RIVER FORECASTS /MIFFS/ CONTINUE TO
INDICATE POTENTIAL RISK FOR SMALL STREAM FLOODING ACROSS SOUTH
CENTRAL AND SOUTHEAST PA WEDNESDAY INTO THURSDAY/FEBRUARY 3-4.
MARFC IS HIGHLIGHTING THIS THREAT IN THEIR SIGNIFICANT FLOOD
OUTLOOK. THE MAIN AREA OF CONCERN AT THIS TIME IS ACROSS THE
JUNIATA AND LOWER MAIN STEM SUSQUEHANNA BASINS. THE FLOOD RISK
WILL BE A COMBINATION OF SNOWMELT/SATURATED GROUND AND FORECAST
MODERATE TO LOCALLY HEAVY RAINFALL. WE ARE ASSESSING THE FLOOD
POTENTIAL AND MAY CONSIDER ISSUING A FLOOD WATCH LATER TODAY.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE/STEINBUGL
HYDROLOGY...
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1126 AM CST MON FEB 1 2016
.UPDATE...
WE ARE ISSUING ONE MORE MINOR UPDATE TO REMOVE THE AREAS OF
MORNING FOG ACROSS PARTS OF CENTRAL TEXAS. OTHERWISE...THE RED
FLAG WARNING FOR EASTLAND AND STEPHENS COUNTIES CONTINUES THIS
AFTERNOON FOR GUSTY SOUTH WINDS AND LOW HUMIDITY VALUES.
THE SKY CONDITION AND TEMPERATURE FORECAST REMAINS CHALLENGING
WITH STRONG WAA THROUGH 850MB CONTINUING...BUT COMPETING WITH
LARGE AREAS OF STRATUS MOVING NORTH...WITH THE LEADING EDGE OF THE
FIRST BATCH CURRENTLY MOVING NORTH OF THE I-20/I-30 CORRIDORS
ALONG AND EAST OF I-35W. STRONGER MIXING HAS ERODED SOME OF THE
STRATUS ACROSS CENTRAL TEXAS...BUT MORE IS MOVING NORTH FROM
SOUTHEAST TEXAS. WENT AHEAD AND BUMPED HIGH TEMPERATURES BACK UP
ACROSS CENTRAL TEXAS AND OUR FAR WESTERN COUNTIES AS MORE SUNSHINE
SHOULD OCCUR ACROSS THESE AREAS THIS AFTERNOON.
05/
&&
.AVIATION...
/ISSUED 1013 AM CST MON FEB 1 2016/
GULF MOISTURE SURGING RAPIDLY NORTH WITH A WARM FRONT THIS
MORNING. IFR CIGS AND FOG AROUND ACT TAF SITE THIS MORNING.
RAP/HRRR SEEM TO BE THE ONLY MODELS PICKING UP ON THE CURRENT
TRENDS.
MVFR CIGS NOW APPROACHING THE METROPLEX TAF SITES...THE WESTERN
EDGE WILL TEND TO ERODE. HAVE MVFR CIGS IN ALL METROPLEX TAFS FOR
THIS AFTERNOON...ALTHOUGH THE THREAT IS LOWER FOR WESTERN SITES
THAN EASTERN SITES. OTHERWISE LIGHT EAST WIND NOW WILL BECOME
SOUTHEAST AND INCREASE TO 15-20KT WITH HIGHER GUSTS THIS
AFTERNOON.
WEAK INSTABILITY ALOFT AND SUFFICIENT MOISTURE SHOULD RESULT IN A
FEW BRIEF SHOWERS AHEAD OF THE FRONT WITH VFR BEHIND THE FRONT
AND WESTERLY WIND AROUND 15KT WILL PREVAIL INTO TUESDAY. MAV/LAV
GUIDANCE LOOKS A LITTLE HIGH WITH WEST WIND TUESDAY MORNING BASED
ON THE FLOW AT 850MB AND A SURFACE LOW TRACKING WELL NORTH OF THE
TAF SITES. DO NOT ANTICIPATE CROSSWIND IMPACTS FOR DFW TUESDAY.
TA..50
&&
.UPDATE...
A STRATUS DECK CONTINUES TO SURGE NORTH EARLY THIS MORNING AND
WILL LIKELY REACH THE I-20/I-30 CORRIDORS LATE THIS MORNING OR BY
MIDDAY. THIS MAY HAVE SOME EFFECT ON HIGH TEMPERATURES THIS
AFTERNOON ACROSS THE EASTERN COUNTIES. HRRR AND SREF MODELS SEEM
TO LOCK ON TO THE STRATUS WELL...WHILE OTHERS WERE TOO OPTIMISTIC.
AREAS OF FOG...SOME LOCALLY DENSE WILL CONTINUE ACROSS CENTRAL
TEXAS THROUGH 10 AM...BEFORE INCREASING SOUTHERLY WINDS AND
WARMING TEMPERATURES HELP DISPERSE ANY FOG. LOOKING AT FORECAST
SOUNDINGS FOR THOSE MODELS INDICATE THAT THOUGH CEILINGS WILL LIFT
WITH WARMING OF THE LOW LEVELS...DECKS WILL REMAIN BROKEN TO
OVERCAST THROUGHOUT THE DAY AND INTO THIS EVENING.
WE HAVE ADJUSTED HIGHS DOWN INTO THE LOWER 70S IN THE EAST TO
ACCOUNT FOR THE LACK OF INSOLATION AS COMPARED TO EARLIER...BUT
WILL MAINTAIN MID TO UPPER 70S ACROSS THE FAR WEST WHERE SOME
VEERING OF LOW LEVEL FLOW AND AT LEAST PARTIAL SUNSHINE IS
EXPECTED. WE WILL CONTINUE THE RED FLAG WARNING FOR EASTLAND AND
STEPHENS COUNTIES. A GRASS FIRE DANGER STATEMENT CONTINUES AS FAR
EAST AS A BOWIE...TO WEATHERFORD...TO LAMPASAS LINE FOR LOW
AFTERNOON HUMIDITY VALUES ...DRIER FUELS AND WARMER TEMPERATURES.
GUSTY SOUTH WINDS OF 15-25 MPH WILL OCCUR THIS AFTERNOON ACROSS
THE WESTERN COUNTIES...WITH SOUTHEAST WINDS 15-20 MPH ELSEWHERE.
05/
&&
.PREV DISCUSSION... /ISSUED 318 AM CST MON FEB 1 2016/
COOLER CONDITIONS ARE CURRENTLY BEING FELT COMPARED TO THIS TIME
YESTERDAY DUE TO THE PASSAGE OF A WEAK COLD FRONT...WHICH HAD
BECOME STATIONARY ALONG THE SOUTHEAST BORDER OF THE FORECAST AREA
THIS MORNING. IN FACT IT LOOKS LIKE THE BOUNDARY HAS ALREADY BEGUN
TO LIFT NORTH IN RESPONSE TO LEE ROCKIES CYCLOGENESIS ASSOCIATED
WITH AN UPPER LEVEL LOW PRESSURE SYSTEM OVER THE SOUTHWEST STATES.
THE UPPER LOW CAN BE SEEN MARCHING EASTWARD ON SATELLITE AND IS
PRODUCING CONVECTION OVER ARIZONA AND NEW MEXICO. THE SYSTEM WILL
CONTINUE ITS EASTWARD ADVANCE TODAY...EVENTUALLY REACHING THE
OKLAHOMA PANHANDLE THIS EVENING BEFORE LIFTING NORTHEAST ACROSS
THE CENTRAL PLAINS TONIGHT AND TUESDAY.
THE SOUTHEASTERN COUNTIES CAN EXPECT FOG DEVELOPMENT THIS MORNING
AS THE MOISTURE RICH AIR ALONG THE FRONT CREEPS IN FROM THE SOUTH.
FOG SHOULD HANG AROUND UNTIL LATE MORNING BUT QUICKLY BURN OFF BY
MIDDAY.
AS FOR THE DEVELOPING STORM OUT WEST...A DEEP SURFACE LOW WILL
ACCOMPANY THE UPPER LEVEL SYSTEM...CREATING A TIGHT PRESSURE
GRADIENT OVER NORTH AND CENTRAL TEXAS AND LEADING TO A WARM AND
WINDY DAY ACROSS THE REGION. THE SOUTH WINDS WILL KICK IN AS THE
SURFACE BOUNDARY OVER THE SOUTHERN COUNTIES LIFTS QUICKLY NORTH
LATER THIS MORNING. SURFACE WINDS SHOULD REMAIN JUST BELOW WIND
ADVISORY CRITERIA...BUT WILL LEAD TO ANOTHER DAY OF HIGH FIRE
DANGER ACROSS THE WEST WHERE THE WARMEST AND DRIEST CONDITIONS
WILL RESIDE. THE TIMING WILL BE DURING THE MID TO LATE AFTERNOON
HOURS AS A DRYLINE NUDGES INTO THE AREA...CREATING MORE OF A
SOUTHWEST WIND COMPONENT ALONG WITH WARMER...DRIER AIR. WE HAVE
DECIDED THAT A RED FLAG WARNING IS NECESSARY FOR THE WESTERN-MOST
COUNTIES FOR THE MID TO LATE AFTERNOON HOURS...WHERE A WINDOW OF
CRITICAL FIRE DANGER WILL BE POSSIBLE.
A COLD FRONT WILL OVERTAKE THE DRY LINE THIS EVENING AS THE STORM
SYSTEM BEGINS TO LIFT NORTHEAST FROM THE OK PANHANDLE/SOUTHWEST
KS INTO THE CENTRAL PLAINS. CONDITIONS ARE EXPECTED TO REMAIN TOO
DRY ACROSS THE WESTERN HALF OF THE REGION FOR ANY PRECIPITATION
ALONG THE FRONT...BUT THERE SHOULD STILL BE ENOUGH MOISTURE FOR A
SLIGHT CHANCE OF SHOWERS AND STORMS ALONG AND EAST OF THE I-35
CORRIDOR LATER THIS EVENING AND OVERNIGHT. IT STILL APPEARS THAT
INSTABILITY WILL REMAIN ON THE LOW SIDE...SO ANY CONVECTION THAT
DEVELOPS WILL LIKELY REMAIN ISOLATED AND SUB-SEVERE.
THE FRONT WILL PUSH EAST OF THE REGION LATE TONIGHT/EARLY TUESDAY
WITH COOLER AND BREEZY CONDITIONS BEHIND IT. A SECOND SURGE OF
COLD AIR WILL ARRIVE AROUND MIDDAY TUESDAY. GOOD COLD AIR
ADVECTION WILL PERSIST TUESDAY NIGHT AND INTO WEDNESDAY AS A
STRONG SURFACE RIDGE BUILDS SOUTH OVER THE AREA. WEDNESDAY/S
TEMPERATURES WILL BEGIN THE MORNING NEAR FREEZING AND STRUGGLE TO
REACH 50 IN MOST LOCATIONS THAT AFTERNOON. LIGHTER WINDS AND
MOSTLY CLEAR SKIES WILL LEAD TO A GOOD RADIATIONAL COOLING NIGHT
WEDNESDAY NIGHT WITH WITH LOWS RANGING FROM THE MID 20S ACROSS THE
NORTHWEST TO LOWER 30S SOUTHEAST.
TEMPERATURES SHOULD RETURN TO NEAR-NORMAL BY FRIDAY AS SOUTHWEST
FLOW DEVELOPS OVERHEAD. ANOTHER UPPER LOW WILL MOVE OVERHEAD LATE
SATURDAY OR SUNDAY...BRINGING A SLIGHT CHANCE OF RAIN THIS
WEEKEND.
30
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 73 49 62 34 50 / 5 10 10 5 5
WACO, TX 76 48 64 34 52 / 5 10 10 5 5
PARIS, TX 72 50 62 33 48 / 10 30 20 10 5
DENTON, TX 73 46 60 31 48 / 5 10 10 5 5
MCKINNEY, TX 72 47 61 32 48 / 5 20 10 5 5
DALLAS, TX 73 50 62 35 50 / 5 20 10 5 5
TERRELL, TX 72 49 63 35 50 / 5 20 10 5 5
CORSICANA, TX 73 50 65 36 52 / 5 20 10 5 5
TEMPLE, TX 78 49 66 34 53 / 5 10 10 5 5
MINERAL WELLS, TX 76 44 60 32 48 / 5 10 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 6 PM CST THIS EVENING FOR TXZ115-129.
&&
$$
/05
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1053 AM CST MON FEB 1 2016
.UPDATE...
STORM SYSTEM CONTINUES TO CHURN TO OUR WEST. MODEL GUIDANCE
CONTINUES TO BE A BIT SLOWER WITH EASTWARD PROGRESSION.
HOWEVER...RAOB DATA DOES HINT AT THE WINDS BEING A BIT STRONGER THAN
THE GUIDANCE SUGGESTS. THE RAOBS BETTER MATCH THE EXPECTATIONS OF
THE PAST FEW DAYS OF FORECAST DATA. AS OF 1030 AM...WINDS ARE JUST
NOW COMING AROUND TO THE SOUTHWEST AND TATUM WITH RAPID RAMP-UP.
FORECAST REMAINS LARGELY ON TRACK THOUGH THIS MORNING/S LIGHT
WINDS ARE A BIT DECEIVING. ...WAIT FOR IT...
GUIDANCE IN GFS/NAM HAS SHIFTED THE H5 WIND MAX ABOUT 60 NM
FURTHER SOUTH THAN DEPICTED YESTERDAY. THOUGH THE HRRR AND RUC
MAINTAIN SOLUTIONS WHICH ARE PARALLEL TO PREVIOUS RUNS. THIS
SHOULD SET UP A BLOWING DUST CORRIDOR FROM NEAR DENVER CITY TOWARD
LUBBOCK BY LATE AFTERNOON.
.AVIATION...
VFR CONDITIONS EXPECTED THIS CYCLE THOUGH WINDS WILL BECOME VERY
GUSTY THIS AFTERNOON AND EXCEED CAPABILITIES OF LIGHT AIRCRAFT.
BLOWING DUST IS MOST LIKELY AT KLBB AND KPVW WHICH HAS THE
POTENTIAL TO DROP US INTO MVFR TERRITORY. THE HIGHEST BLDU THREAT
APPEARS TO BE AT KLBB AFTER 20Z. NOT GOING TO BE A GOOD DAY FOR
SMOOTH AIR.
&&
.PREV DISCUSSION... /ISSUED 548 AM CST MON FEB 1 2016/
AVIATION...
ALTHOUGH VFR CONDITIONS WILL PREVAIL...VERY STRONG SOUTHWEST TO
WEST WINDS ARE EXPECTED TO SPREAD OVER THE REGION THIS AFTERNOON
CREATING AREAS OF BLOWING DUST. SUSTAINED WINDS IN EXCESS OF 30
KTS WILL BE POSSIBLE AT LBB AND PVW AFTER 19Z.
PREV DISCUSSION... /ISSUED 458 AM CST MON FEB 1 2016/
SHORT TERM...
STRONG UPPER LOW ROTATING THROUGH THE SOUTHERN ROCKIES WILL EJECT
INTO THE PLAINS STATES TO OUR NORTH THIS EVENING.AS IT DOES...WE
WILL HAVE A VERY TIGHT PRESSURE OVER THE REGION. THE 700MB
GRADIENT IS IN A RANGE SUPPORTIVE OF 35-40 MPH SUSTAINED SURFACE
WINDS WITH GUSTS ON THE ORDER OF 55-60 MPH. AS SUCH WE ARE
UPGRADING THE HIGH WIND WATCH TO A WARNING WHICH WILL RUN FROM
NOON TILL 6 PM. WE ALSO CONTINUE TO MENTION A SLIGHT CHANCE OF
SHOWERS IN THE EXTREME SOUTHERN PANHANDLE...BUT ANY PRECIPITATION
WILL PROBABLY BE MOSTLY IN THE FORM OF VIRGA AND THAT COULD
EXTEND SOUTHWARD ACROSS THE ENTIRE AREA.
ALTHOUGH WE HAVE A HIGH WIND WARNING IN EFFECT...WE WILL START OFF
THE DAY WITH RELATIVELY MILD SOUTHEAST TO SOUTH WINDS. THE WINDS
ARE EXPECTED TO SHIFT TO THE SOUTHWEST AND INCREASE SHARPLY AS A
PACIFIC FRONT MOVES ACROSS THE REGION. THE HIGH WINDS ARE EXPECTED
TO ENTER THE WESTERN SOUTH PLAINS AROUND NOON AND THEN SPREAD
RAPIDLY EASTWARD. THE HIGH WINDS SHOULD APPROACH A LUBBOCK TO
PLAINVIEW LINE BETWEEN 1 AND 2 PM AND CONTINUING EAST. WIND SPEEDS
OFF THE CAPROCK SHOULD BE BELOW HIGH WIND CRITERIA.
LONG TERM...
COOLER AND BREEZY CONDITIONS BEHIND THE DEPARTING WIND STORM ON
TUESDAY LOOK ON TRACK. DRY LOWER LEVELS BUT AN APPROACHING
DISTURBANCE WILL INTERACT WITH THE SLOPED FRONT OVER EASTERN NEW
MEXICO INTO OUR WESTERN ZONES EARLY WEDNESDAY TO DEVELOP LIFT IN
THE 700 MB AREA...STILL CAPABLE OF LIGHT SNOW SHOWERS SUPPOSING
LIFT PERSISTS LONG ENOUGH TO SATURATE LOWER LEVELS AT LEAST
SOMEWHAT. EITHER WAY...ONLY TRACE AMOUNTS ARE EXPECTED AT BEST.
LATER WEDNESDAY SHOULD REMAIN CHILLY WITH LIGHT WINDS WHILE MODEST
WARMING IS EXPECTED THURSDAY PERHAPS INTO FRIDAY.
SOLUTIONS ARE MORE WOUND-UP WITH THE NEXT BALL OF ENERGY EXPECTED
TO DIVE SOUTHEAST TOWARDS THE SOUTHERN ROCKIES AND HIGH PLAINS ON
FRIDAY. AIRMASS SHOULD BE QUITE DRY IN LOWER LEVELS GOING IN. BUT
ASSUMING AGAIN THAT AT LEAST MODERATELY STRONG DEEP LIFT OCCURS AS
CURRENTLY INDICATED THURSDAY NIGHT INTO FRIDAY...WE CAN ACCEPT A
MINIMAL MENTION OF LIGHT RAIN OR SNOW SHOWERS FRIDAY AS SPAT OUT
BY OUR BLENDED SOLUTIONS. CURRENT RUNS NOW SHOW POTENTIAL FOR
MODEST WARMING BY SUNDAY IN ADVANCE OF ANOTHER CARVING-TYPE UPPER
TROUGH AND COOLING EARLY OF THE NEXT WEEK. SO...AN ACTIVE PATTERN
IS EXPECTED THROUGH THE WEEK ALTHOUGH LACKING MOISTURE AND THUS
POTENTIAL FOR MORE NOTABLE WEATHER. RMCQUEEN
FIRE WEATHER...
HIGH WINDS AND LOW HUMIDITIES ARE SUPPORTIVE OF A RED FLAG
WARNING FOR THE SOUTHERN AND EASTERN HALF OF THE AREA. BECAUSE OF
THE STRENGTH OF THE WINDS...ANY FIRES THAT DO BREAK OUT WILL HAVE
THE POTENTIAL TO SPREAD EXPLOSIVELY. SINCE WINDS ARE EXPECTED TO
REMAIN HIGH THROUGH EARLY EVENING WITH HUMIDITIES ALSO SLOW TO
RECOVER...WE WILL LET THE RED FLAG WARNING CONTINUE UNTIL MID
EVENING.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM CST THIS EVENING FOR TXZ025-026-
030>032-035>038-040>044.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR TXZ021>024-
027>030-033>036-039>041.
&&
$$
26/99
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1013 AM CST MON FEB 1 2016
.AVIATION UPDATE...
GULF MOISTURE SURGING RAPIDLY NORTH WITH A WARM FRONT THIS
MORNING. IFR CIGS AND FOG AROUND ACT TAF SITE THIS MORNING.
RAP/HRRR SEEM TO BE THE ONLY MODELS PICKING UP ON THE CURRENT
TRENDS.
MVFR CIGS NOW APPROACHING THE METROPLEX TAF SITES...THE WESTERN
EDGE WILL TEND TO ERODE. HAVE MVFR CIGS IN ALL METROPLEX TAFS FOR
THIS AFTERNOON...ALTHOUGH THE THREAT IS LOWER FOR WESTERN SITES
THAN EASTERN SITES. OTHERWISE LIGHT EAST WIND NOW WILL BECOME
SOUTHEAST AND INCREASE TO 15-20KT WITH HIGHER GUSTS THIS
AFTERNOON.
WEAK INSTABILITY ALOFT AND SUFFICIENT MOISTURE SHOULD RESULT IN A
FEW BRIEF SHOWERS AHEAD OF THE FRONT WITH VFR BEHIND THE FRONT
AND WESTERLY WIND AROUND 15KT WILL PREVAIL INTO TUESDAY. MAV/LAV
GUIDANCE LOOKS A LITTLE HIGH WITH WEST WIND TUESDAY MORNING BASED
ON THE FLOW AT 850MB AND A SURFACE LOW TRACKING WELL NORTH OF THE
TAF SITES. DO NOT ANTICIPATE CROSSWIND IMPACTS FOR DFW TUESDAY.
TA..50
&&
.UPDATE...
A STRATUS DECK CONTINUES TO SURGE NORTH EARLY THIS MORNING AND
WILL LIKELY REACH THE I-20/I-30 CORRIDORS LATE THIS MORNING OR BY
MIDDAY. THIS MAY HAVE SOME EFFECT ON HIGH TEMPERATURES THIS
AFTERNOON ACROSS THE EASTERN COUNTIES. HRRR AND SREF MODELS SEEM
TO LOCK ON TO THE STRATUS WELL...WHILE OTHERS WERE TOO OPTIMISTIC.
AREAS OF FOG...SOME LOCALLY DENSE WILL CONTINUE ACROSS CENTRAL
TEXAS THROUGH 10 AM...BEFORE INCREASING SOUTHERLY WINDS AND
WARMING TEMPERATURES HELP DISPERSE ANY FOG. LOOKING AT FORECAST
SOUNDINGS FOR THOSE MODELS INDICATE THAT THOUGH CEILINGS WILL LIFT
WITH WARMING OF THE LOW LEVELS...DECKS WILL REMAIN BROKEN TO
OVERCAST THROUGHOUT THE DAY AND INTO THIS EVENING.
WE HAVE ADJUSTED HIGHS DOWN INTO THE LOWER 70S IN THE EAST TO
ACCOUNT FOR THE LACK OF INSOLATION AS COMPARED TO EARLIER...BUT
WILL MAINTAIN MID TO UPPER 70S ACROSS THE FAR WEST WHERE SOME
VEERING OF LOW LEVEL FLOW AND AT LEAST PARTIAL SUNSHINE IS
EXPECTED. WE WILL CONTINUE THE RED FLAG WARNING FOR EASTLAND AND
STEPHENS COUNTIES. A GRASS FIRE DANGER STATEMENT CONTINUES AS FAR
EAST AS A BOWIE...TO WEATHERFORD...TO LAMPASAS LINE FOR LOW
AFTERNOON HUMIDITY VALUES ...DRIER FUELS AND WARMER TEMPERATURES.
GUSTY SOUTH WINDS OF 15-25 MPH WILL OCCUR THIS AFTERNOON ACROSS
THE WESTERN COUNTIES...WITH SOUTHEAST WINDS 15-20 MPH ELSEWHERE.
05/
&&
.PREV DISCUSSION... /ISSUED 318 AM CST MON FEB 1 2016/
COOLER CONDITIONS ARE CURRENTLY BEING FELT COMPARED TO THIS TIME
YESTERDAY DUE TO THE PASSAGE OF A WEAK COLD FRONT...WHICH HAD
BECOME STATIONARY ALONG THE SOUTHEAST BORDER OF THE FORECAST AREA
THIS MORNING. IN FACT IT LOOKS LIKE THE BOUNDARY HAS ALREADY BEGUN
TO LIFT NORTH IN RESPONSE TO LEE ROCKIES CYCLOGENESIS ASSOCIATED
WITH AN UPPER LEVEL LOW PRESSURE SYSTEM OVER THE SOUTHWEST STATES.
THE UPPER LOW CAN BE SEEN MARCHING EASTWARD ON SATELLITE AND IS
PRODUCING CONVECTION OVER ARIZONA AND NEW MEXICO. THE SYSTEM WILL
CONTINUE ITS EASTWARD ADVANCE TODAY...EVENTUALLY REACHING THE
OKLAHOMA PANHANDLE THIS EVENING BEFORE LIFTING NORTHEAST ACROSS
THE CENTRAL PLAINS TONIGHT AND TUESDAY.
THE SOUTHEASTERN COUNTIES CAN EXPECT FOG DEVELOPMENT THIS MORNING
AS THE MOISTURE RICH AIR ALONG THE FRONT CREEPS IN FROM THE SOUTH.
FOG SHOULD HANG AROUND UNTIL LATE MORNING BUT QUICKLY BURN OFF BY
MIDDAY.
AS FOR THE DEVELOPING STORM OUT WEST...A DEEP SURFACE LOW WILL
ACCOMPANY THE UPPER LEVEL SYSTEM...CREATING A TIGHT PRESSURE
GRADIENT OVER NORTH AND CENTRAL TEXAS AND LEADING TO A WARM AND
WINDY DAY ACROSS THE REGION. THE SOUTH WINDS WILL KICK IN AS THE
SURFACE BOUNDARY OVER THE SOUTHERN COUNTIES LIFTS QUICKLY NORTH
LATER THIS MORNING. SURFACE WINDS SHOULD REMAIN JUST BELOW WIND
ADVISORY CRITERIA...BUT WILL LEAD TO ANOTHER DAY OF HIGH FIRE
DANGER ACROSS THE WEST WHERE THE WARMEST AND DRIEST CONDITIONS
WILL RESIDE. THE TIMING WILL BE DURING THE MID TO LATE AFTERNOON
HOURS AS A DRYLINE NUDGES INTO THE AREA...CREATING MORE OF A
SOUTHWEST WIND COMPONENT ALONG WITH WARMER...DRIER AIR. WE HAVE
DECIDED THAT A RED FLAG WARNING IS NECESSARY FOR THE WESTERN-MOST
COUNTIES FOR THE MID TO LATE AFTERNOON HOURS...WHERE A WINDOW OF
CRITICAL FIRE DANGER WILL BE POSSIBLE.
A COLD FRONT WILL OVERTAKE THE DRY LINE THIS EVENING AS THE STORM
SYSTEM BEGINS TO LIFT NORTHEAST FROM THE OK PANHANDLE/SOUTHWEST
KS INTO THE CENTRAL PLAINS. CONDITIONS ARE EXPECTED TO REMAIN TOO
DRY ACROSS THE WESTERN HALF OF THE REGION FOR ANY PRECIPITATION
ALONG THE FRONT...BUT THERE SHOULD STILL BE ENOUGH MOISTURE FOR A
SLIGHT CHANCE OF SHOWERS AND STORMS ALONG AND EAST OF THE I-35
CORRIDOR LATER THIS EVENING AND OVERNIGHT. IT STILL APPEARS THAT
INSTABILITY WILL REMAIN ON THE LOW SIDE...SO ANY CONVECTION THAT
DEVELOPS WILL LIKELY REMAIN ISOLATED AND SUB-SEVERE.
THE FRONT WILL PUSH EAST OF THE REGION LATE TONIGHT/EARLY TUESDAY
WITH COOLER AND BREEZY CONDITIONS BEHIND IT. A SECOND SURGE OF
COLD AIR WILL ARRIVE AROUND MIDDAY TUESDAY. GOOD COLD AIR
ADVECTION WILL PERSIST TUESDAY NIGHT AND INTO WEDNESDAY AS A
STRONG SURFACE RIDGE BUILDS SOUTH OVER THE AREA. WEDNESDAY/S
TEMPERATURES WILL BEGIN THE MORNING NEAR FREEZING AND STRUGGLE TO
REACH 50 IN MOST LOCATIONS THAT AFTERNOON. LIGHTER WINDS AND
MOSTLY CLEAR SKIES WILL LEAD TO A GOOD RADIATIONAL COOLING NIGHT
WEDNESDAY NIGHT WITH WITH LOWS RANGING FROM THE MID 20S ACROSS THE
NORTHWEST TO LOWER 30S SOUTHEAST.
TEMPERATURES SHOULD RETURN TO NEAR-NORMAL BY FRIDAY AS SOUTHWEST
FLOW DEVELOPS OVERHEAD. ANOTHER UPPER LOW WILL MOVE OVERHEAD LATE
SATURDAY OR SUNDAY...BRINGING A SLIGHT CHANCE OF RAIN THIS
WEEKEND.
30
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 72 49 62 34 50 / 5 10 10 5 5
WACO, TX 73 48 64 34 52 / 5 10 10 5 5
PARIS, TX 71 50 62 33 48 / 10 30 20 10 5
DENTON, TX 72 46 60 31 48 / 5 10 10 5 5
MCKINNEY, TX 71 47 61 32 48 / 5 20 10 5 5
DALLAS, TX 72 50 62 35 50 / 5 20 10 5 5
TERRELL, TX 71 49 63 35 50 / 5 20 10 5 5
CORSICANA, TX 72 50 65 36 52 / 5 20 10 5 5
TEMPLE, TX 74 49 66 34 53 / 5 10 10 5 5
MINERAL WELLS, TX 75 44 60 32 48 / 5 10 10 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 2 PM THIS AFTERNOON TO 6 PM CST THIS
EVENING FOR TXZ115-129.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
416 PM EST MON FEB 1 2016
.SYNOPSIS...
A COLD FRONT WILL CROSS OVERHEAD THIS EVENING...AND MOVE SOUTHWARD
TOWARD THE CAROLINAS BY MIDNIGHT. THIS FRONT SHOULD STALL AND
RETURN NORTHWARD AS A WARM FRONT LATE TUESDAY NIGHT. A STRONGER
COLD FRONT WILL ARRIVE ON WEDNESDAY TO BRING WIDESPREAD RAIN...AND
COOLER AND DRIER WEATHER SHOULD FOLLOW LATER IN THE WEEK.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 400 PM EST MONDAY...
SCATTERED SHOWERS CONTINUE TO TRACK TO THE NORTHEAST...BUT
RAIN IS ONLY BEING REALIZED ALONG AND WEST OF THE BLUE RIDGE. THE
SHOWERS FIZZLE ON THE EASTERN SIDE DUE TO DOWNSLOPING WEST WINDS.
IN THE PIEDMONT...WARM AIR ADVECTION CONTINUES TO PUSH HIGHS INTO
THE MID 60S TO THE LOWER 70S THIS EVENING. THE RAIN INTENSITY
SHOULD DECREASE TONIGHT...AS THE COLD FRONT MOVES SOUTH OF THE
CWA. TEMPERATURES SHOULD BEGIN A CONSIDERABLE DROP...AS HIGH
PRESSURE NOSES SOUTHWARD AND WEDGES ALONG THE EASTERN SLOPES OF
THE BLUE RIDGE. WINDS SHOULD SHIFT TO THE NORTHEAST...AND PUT THE
CWA UNDER PATCHY DRIZZLE...FOG...AND LOW CLOUDS. LOWS WERE HELD
BELOW MOS GUIDANCE DUE TO THESE AFOREMENTIONED WEATHER
ELEMENTS...WITH MID 30S TO THE MID 40S EXPECTED.
BY TUESDAY...ABUNDANT LOW LEVEL MOISTURE AND OVERRUNNING WARM AIR
ADVECTION...WILL KEEP LOCATIONS ALONG AND EAST OF THE BLUE RIDGE
CLOUDY AND DRIZZLY. AS THE COLD FRONT STALLS OVER THE
CAROLINAS...THE COOL WEDGE OF HIGH PRESSURE SHOULD REMAIN IN
PLACE. HIGH TEMPERATURES WERE HELD BELOW GUIDANCE TO MAINLY LOWER
40S TO MID 50S ALONG AND EAST OF THE BLUE RIDGE...AS THE DIURNAL
RANGE SHOULD BE LIMITED. HOWEVER...FAR SOUTHWEST VIRGINIA SHOULD
STAY FREE OF THE COOL WEDGE AND REACH THE MID TO UPPER 50S. WINDS
WILL BEGIN TO PICK UP FROM THE SOUTH AND SOUTHEAST BY TUESDAY
AFTERNOON ALONG THE WESTERN SLOPES...IN RESPONSE TO A HEALTHY LOW
LEVEL JET AHEAD OF A STRONG COLD FRONT APPROACHING FROM THE WEST.
THUS...WIND GUSTS COULD INCREASE TO 30 MPH BY THE EVENING.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
AS OF 400 PM EST MONDAY...
STRONG COLD FRONT WILL APPROACH THE AREA TUESDAY NIGHT...CROSSING
THE CENTRAL APPALACHIANS WEDNESDAY. A STRONG SOUTH-SOUTHEAST LOW
LEVEL JET IS PROGGED AHEAD OF THE FRONT...85H WINDS OF 50-65KTS.
EAST OF THE APPALACHIAN DIVIDE...THE FORECAST AREA WILL REMAIN UNDER
THE INFLUENCE OF A LINGERING WEDGE...SO THESE WINDS WILL REMAIN
ABOVE THE INVERSION. WEST OF THE APPALACHIAN DIVIDE FROM TENNESSEE
UP THROUGH FAR WESTERN VA INTO PARTS OF WV...THESE WINDS WILL LIKELY
MIX TO THE SURFACE...WITH GUSTS OF 40-50 MPH. THIS WILL MAINLY
IMPACT AREAS WEST OF MOUNTAIN EMPIRE VA...SMYTH...TAZEWELL COUNTIES
IN VA TOWARD BRISTOL...AND MAINLY WEST OF THE NC/TN BORDER. WILL
HIGHLIGHT THIS THREAT IN THE HWO IN FAVOR OF A WIND ADVISORY FOR
THAT AREA FOR TUESDAY NIGHT AND UP UNTIL THE FRONTAL PASSAGE
WEDNESDAY.
RAIN POTENTIAL WILL INCREASE TUESDAY NIGHT AND INTO THE DAY
WEDNESDAY WITH CATEGORICAL POPS ADVERTISED ACROSS THE ENTIRE
FORECAST AREA...ESP ALONG AND JUST AHEAD OF THE FRONT WEDNESDAY.
MODEL QPF IS FOR BETWEEN A HALF /0.50/ TO ONE INCH /1.00/ OF
RAIN...ENOUGH TO CAUSE STREAMS TO RISE...BUT NOT ENOUGH TO FLOOD.
AREAS WHICH STILL HAVE SNOW COVER...PARTICULARLY THE GREENBRIER
VALLEY OF WV...WILL HAVE TO BE CLOSELY MONITORED AS THERE IS
APPROXIMATELY AN INCH /1.00/ OF LIQUID EQUIVALENT REMAINING IN THE
SNOWPACK ACROSS THE HIGHLANDS OF SOUTHEAST WVA. AN INCH OF RAIN
PLUS AND INCH OF SNOW MELT WILL LIKELY CAUSE A SUBSTANTIAL RISE
ALONG THE GREENBRIER RIVER...MODELS SUGGESTING 3/4 BANK FULL.
MODELS HAVE SLOWED THE PASSAGE OF THE FRONT ON WEDNESDAY...BY ABOUT
3 HOURS COMPARED TO YESTERDAYS MODEL RUNS...SUGGESTING THE FRONT
WILL COME THROUGH THE MOUNTAINS MID-DAY 1200-1400 LST...THEN
CLEARING THE PIEDMONT DURING THE EVENING...1800-2100 LST. PASSAGE OF
THE FRONT WILL BRING AN END TO THE WIND THREAT IN THE WEST. RAIN
SHOULD ALSO COME TO AN END WITHIN AN HOUR OF TWO OF FROPA.
MODELS ARE IN GENERAL AGREEMENT THIS FRONT WILL MOVE TO THE COAST
WEDNESDAY NIGHT BEFORE STALLING OFF SHORE. EVEN IF A WAVE OF LOW
PRESSURE DEVELOPS ALONG THE FRONT...WHICH SOME OF THE MODELS ARE
SUGGESTING...IT SHOULD BE JUST FAR ENOUGH EAST NOT TO IMPACT OUR
FORECAST AREA WITH ANYTHING OTHER THAN CLOUD COVER. THAT
SAID...THERE WILL BE FLURRIES ACROSS OUR MOUNTAINS AS COLDER AIR
ARRIVES FROM THE NORTHWEST...THE LINGERING LOW LEVEL CLOUD COVER
YIELDING TO DENDRITIC CRYSTAL GROWTH AS 85H TEMPERATURES SLIP INTO
THE M8 TO M12 DEG C RANGE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 400 PM EST MONDAY...
A TREND TOWARD MUCH COLDER CONDITIONS AND GENERALLY DRY WEATHER
EXPECTED FOR THE WEEKEND. HOWEVER...MODELS STILL SOMEWHAT
TROUBLESOME ABOUT POTENTIAL FOR LOW PRESSURE DEVELOPING ALONG THE
REMNANT FRONTAL BOUNDARY/BAROCLINIC ZONE ALONG THE SOUTHEAST U.S.
COAST. AN EASTERN CONUS LONG WAVE TROUGH IS DESTINED TO REMAIN IN
PLACE WELL INTO NEXT WEEK...WITH VARIED AMOUNTS OF SHORT WAVE ENERGY
PROGGED TO PASS THROUGH THE FLOW. THE QUESTION...WILL ANY OF THIS
ENERGY SPAWN SOMETHING THAT WOULD PRODUCE MORE THAN JUST THE TYPICAL
UPSLOPE SNOW SHOWERS. UNTIL THE MODELS RESOLVE THIS ISSUE...
FORECAST CONFIDENCE IS LOW WITH RESPECT TO TIMING OF ANY SPECIFIC
FEATURE. OF MORE CERTAINTY IS THE FACT THAT TEMPERATURES WILL TREND
COLDER...PROBABLY ENDING UP WELL BELOW NORMAL BY THE MIDDLE OF NEXT
WEEK.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
AS OF 100 PM EST MONDAY...
A COLD FRONT CROSSING OVER THE APPALACHIAN MOUNTAINS WILL BRING
LOWERED CEILINGS AND SCATTERED RAIN SHOWERS THIS AFTERNOON. SHORT
TERM MODELS ARE VARYING WITH THE TIMING AND COVERAGE...BUT IT
SEEMS THE RAP IS CLOSEST TO CURRENT RADAR TRENDS. MVFR/IFR
CEILINGS AND VISIBILITIES ARE POSSIBLE IN THE AFTERNOON...AND
HAVE BEEN MENTIONED AT ALL SITES AS A TEMPO GROUP. THE THREAT OF
LOW LEVEL WIND SHEAR FROM EARLIER THIS MORNING HAS NOW
DIMINISHED...SO THAT ELEMENT HAS BEEN TAKEN OUT OF THE TAFS.
FLYING CONDITIONS SHOULD DETERIORATE EVEN FURTHER TONIGHT...AS
HIGH PRESSURE BEHIND THE COLD FRONT WEDGES SOUTHWARD AGAINST THE
EASTERN SLOPES OF THE BLUE RIDGE. ALTHOUGH THE SHOWERS WILL
END...DRIZZLE AND/OR FOG SHOULD DEVELOP AFTER MIDNIGHT AS WINDS
SHIFT TO THE NORTHEAST. CONFIDENCE IS QUITE HIGH THAT IFR
CONDITIONS WILL BE EXPERIENCED AT ALL SITES...ESPECIALLY BY DAWN
ON TUESDAY. CEILINGS AND VISIBILITIES MAY GRADUALLY IMPROVE DURING
THE DAY...BUT IT SEEMS LIKELY THAT IFR CONDITIONS WILL REMAIN
INTACT BY 18Z.
EXTENDED DISCUSSION...
ABUNDANT LOW LEVEL MOISTURE IN A COOL WEDGE EAST OF THE BLUE
RIDGE ALONG WITH OVERRUNNING WARM AIR ADVECTION WILL RESULT IN
IFR CONDITIONS ON TUESDAY AFTERNOON. SOME IMPROVEMENT TO MVFR IS
POSSIBLE LATE IN THE DAY. A STRONG COLD FRONT SHOULD ARRIVE ON
WEDNESDAY...AND IT PROMISES TO BRING IFR/MVFR CONDITIONS AND A
PERIOD OF MODERATE RAIN. BY THURSDAY...HIGH PRESSURE WILL BUILD
OVERHEAD TO PROVIDE COLDER AND DRIER CONDITIONS...AND ALSO PROVIDE
A RECOVERY TO VFR CONDITIONS AT ALL TAF SITES.
&&
.EQUIPMENT...
AS OF 400 PM EST MONDAY...
THE KFCX RADAR IS BACK IN SERVICE...BUT THERE ARE STILL SOME
MAINTENANCE ISSUES TO BE RESOLVED. TECHNICIANS ARE INVESTIGATING
THE PROBLEMS...BUT THERE IS NO KNOWN TIME WHEN ALL REPAIRS WILL BE
COMPLETED.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PW
NEAR TERM...PW
SHORT TERM...PM
LONG TERM...PM
AVIATION...PW
EQUIPMENT...PW
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1258 PM EST MON FEB 1 2016
.SYNOPSIS...
A COLD FRONT ENTERS THE REGION THIS AFTERNOON...AND MOVES
SOUTHWARD TO THE NORTH CAROLINA/SOUTH CAROLINA BORDER BY MIDNIGHT.
THIS FRONT SHOULD RETURN NORTHWARD AS A WARM FRONT LATE TUESDAY
NIGHT. A STRONGER COLD FRONT WILL ARRIVE ON WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1103 AM EST MONDAY...
A LINE OF RAIN SHOWERS IS ENTERING THE WESTERN SLOPES AT THIS
HOUR. MORE TWEAKS TO THE POPS AND TEMPERATURES HAVE BEEN MADE TO
ACCOUNT FOR THE LATEST OBSERVATIONS AND RADAR TRENDS. THE COLD
FRONT SHOULD BISECT THE CWA FROM SOUTHWEST TO NORTHEAST BY THE
AFTERNOON. QPF SHOULD VARY FROM A TENTH TO A QUARTER OF AN INCH.
HIGHS WILL VARY SIGNIFICANTLY THIS AFTERNOON...WITH UPPER 40S TO
THE MID 50S WEST OF THE BLUE RIDGE WHERE CLOUD COVER AND RAINFALL
CHANCES ARE HIGHER...AND LOWER TO MID 60S IN THE PIEDMONT WHERE
CLOUD COVER AND RAINFALL CHANCES ARE LOWER.
TONIGHT...THE FRONT ENTERS NC AND STALLS ALONG THE SRN NC AREA.
MODELS ARE DRYING THE NRN CWA OUT BY MIDNIGHT WITH FORECAST
SOUNDINGS AND HIGH RES MODELS ATTEMPTING TO PAINT RAIN OVER THE
SRN TIER OF THE CWA OVERNIGHT. WITH HIGH PRESSURE MOVING SOUTHEAST
INTO THE MID ATLANTIC STATES...THE FLOW TURNS NE TO EAST. THIS
HAPPENING AT NIGHT WITH INVERSION SETTING UP IN THE LOW LVLS
SHOULD ACT TO HOLD CLOUDS IN WITH LIGHT RAIN/DRIZZLE SET UP ACROSS
SOUTHSIDE VA INTO THE NW NC AREA...AND AS FAR NORTH AS THE NEW
RIVER VALLEY/BLUE RIDGE AROUND ROANOKE SOUTH. WITH THIS IN
MIND...THINK TEMPS WILL STAY COOLER THAN PREVIOUS
FORECAST...THOUGH CLOUDS WILL HOLD TEMPS UP. WILL START THE
EVENING WITH CHANCE POPS MOST PLACES...THEN DRY OUT THE SE WV
GREENBRIER VALLEY AREA BY MIDNIGHT AND LOWER TO SLIGHT CHANCE OVER
MOST OF THE CWA...THEN DROP BELOW 15 PERCENT MOST AREAS BY DAWN
BUT HOLD SLIGHT TO LOW CHANCE IN THE NC MOUNTAINS/FOOTHILLS...NE
INTO THE VA FOOTHILLS. LOW TEMPS WILL RANGE FROM THE MID TO UPPER
30S GREENBRIER VALLEY TO ALLEGHANYS AS MAY EVEN SEE SOME CLEARING
BRIEFLY...TO LOWER TO MID 40S ELSEWHERE.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 307 AM EST MONDAY...
FOLLOWING THE PASSING OF A FRONT MONDAY NIGHT...HIGH PRESSURE WILL
WEDGE SOUTH INTO THE CAROLINAS ON TUESDAY. THE COMBINATION OF COOL
LOW LEVEL EASTERLY FLOW AND WARM MOIST SOUTHWESTERLY FLOW ALOFT WILL
KEEP THE FORECAST AREA IN GRAY AND DAMP CONDITIONS TUESDAY AND
TUESDAY NIGHT. EASTERLY FLOW AND ISENTROPIC LIFT WILL SPREAD
RAIN/DRIZZLE FROM THE NORTH CAROLINA HIGH COUNTRY IN THE MORNING
TO THE ALLEGHANY HIGHLANDS IN THE AFTERNOON. ALL AREAS ALONG AND
EAST OF THE BLUE RIDGE WILL HAVE RAIN/DRIZZLE AND/OR FOG TUESDAY
NIGHT. THIS WEDGE WILL ERODE SOME AS A COLD FRONT APPROACHES THE
REGION LATE TUESDAY NIGHT INTO WEDNESDAY. WIDESPREAD SHOWERS ARE
EXPECTED TO MOVE EAST WITH THE FRONT DURING THE DAY
WEDNESDAY...CLEARING THE PIEDMONT BY EVENING RUSH HOUR. THERE IS A
POSSIBILITY THAT THE FRONT COULD STALL OVER THE PIEDMONT OR REMAIN
IN THE VICINITY OF THE AREA IF RIDGING IN THE WESTERN ATLANTIC
REMAINS ANCHORED. FOR THIS PACKAGE...WE WILL KEEP THE FRONT
PROGRESSIVE AND MOVING TO THE EAST COAST WEDNESDAY NIGHT.
TEMPERATURES ARE EXPECTED TO REMAIN MILD AS THE WEDGE DRIFTS SOUTH
TUESDAY...THEREFORE WE ARE NOT LOOKING AT A WINTRY MIX...JUST A
PLAIN OLE COLD RAIN. INTENSITY OF THE RAIN WILL INCREASE AS THE
FRONT MOVES OVER THE REGION. WE WOULD NOT BE SURPRISED TO HEAR SOME
THUNDER AS DYNAMICS WITH THIS SYSTEM ARE IMPRESSIVE...BUT WE ARE NOT
EXPECTING ANY THING SEVERE. SOME HYDRO CONCERNS WITH SLOW MELTING
SNOWPACK ACROSS THE MOUNTAINS AND HIGH RAINFALL RATES WEDNESDAY.
FORECASTED RAINFALL AMOUNTS FOR THIS EVENT SHOULD REMAIN UNDER AN
INCH...WHICH THE AREA SHOULD BE ABLE TO HANDLE WITH NO PROBLEM.
AREAS WITHIN THE WEDGE TUESDAY WILL SEE TEMPERATURES IN THE MID 40S
WHILE OUTSIDE THE WEDGE WILL BE CLOSER TO 60F (BLUEFIELD-RICHLANDS).
TEMPERATURES ACROSS THE AREA WILL NOT FALL MUCH TUESDAY NIGHT. AS
THE FRONT APPROACHES THE REGION...SOME LOCATIONS MAY SEE A RISE IN
TEMPERATURES AS THE WEDGE ERODES. TEMPERATURES WILL PEAK IN THE
UPPER 50S WEST TO MID 60S EAST WEDNESDAY. THE COLD AIR WILL LAG
BEHIND WITH THE DEW POINT FRONT...WITH LOWS WEDNESDAY NIGHT ONLY
DROPPING INTO THE LOWER 30S WEST TO LOWER 40S EAST.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 407 PM EST SUNDAY...
A TREND TOWARD MUCH COLDER CONDITIONS AND GENERALLY DRY WEATHER
EXPECTED FOR THE WEEKEND. HOWEVER...MODELS STILL SOMEWHAT
TROUBLESOME ABOUT LOW PRESSURE DEVELOPING ALONG THE REMNANT FRONTAL
BOUNDARY/BAROCLINIC ZONE ALONG THE SOUTHEAST U.S. COAST. MODEL
CONSENSUS IS TO KEEP THIS PRECIPITATION SOUTH AND EAST OF OUR REGION
AND THIS PACKAGE CONTINUES TO ADVERTISE A DRY FORECAST FOR THE RNK
CWA IN THE EXTENDED PERIODS. THIS AGREES WITH WPC THINKING ATTM.
THE EASTERN U.S. TROUGH IS DESTINED TO REMAIN IN PLACE INTO THE
WEEKEND AND AT LEAST THE FIRST HALF OF THE FOLLOWING WEEK AS SEVERAL
ALBERTA CLIPPERS TRACK THROUGH THE EASTERN CONUS HELPING TO
REINFORCE AND DEEPEN THE TROUGH. SEVERAL SURGES OF CANADIAN/ARCTIC
AIR ARE PROGGED TO SPREAD SOUTHEAST...THE INTENSITY OF WHICH VARIES
ACCORDING TO WHATEVER MODEL YOU CHOOSE TO LOOK AT. NONETHELESS...A
TREND TOWARD NORMAL AND EVEN BELOW NORMAL TEMPERATURES APPEARS
LIKELY. QUESTION THEN BECOMES WILL THERE BE ANY SHORT WAVE ENERGY
TO ROUND THE BASE OF THE UPPER TROUGH TO SPAWN SOMETHING THAT
WOULD PRODUCE MORE THAN JUST THE TYPICAL UPSLOPE SNOW SHOWERS.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 1258 PM EST MONDAY...
A COLD FRONT CROSSING OVER THE APPALACHIAN MOUNTAINS WILL BRING
LOWERED CEILINGS AND SCATTERED RAIN SHOWERS THIS AFTERNOON. SHORT
TERM MODELS ARE VARYING WITH THE TIMING AND COVERAGE...BUT IT
SEEMS THE RAP IS CLOSEST TO CURRENT RADAR TRENDS. MVFR/IFR
CEILINGS AND VISIBILITIES ARE POSSIBLE IN THE AFTERNOON...AND
HAVE BEEN MENTIONED AT ALL SITES AS A TEMPO GROUP. THE THREAT OF
LOW LEVEL WIND SHEAR FROM EARLIER THIS MORNING HAS NOW
DIMINISHED...SO THAT ELEMENT HAS BEEN TAKEN OUT OF THE TAFS.
FLYING CONDITIONS SHOULD DETERIORATE EVEN FURTHER TONIGHT...AS
HIGH PRESSURE BEHIND THE COLD FRONT WEDGES SOUTHWARD AGAINST THE
EASTERN SLOPES OF THE BLUE RIDGE. ALTHOUGH THE SHOWERS WILL
END...DRIZZLE AND/OR FOG SHOULD DEVELOP AFTER MIDNIGHT AS WINDS
SHIFT TO THE NORTHEAST. CONFIDENCE IS QUITE HIGH THAT IFR
CONDITIONS WILL BE EXPERIENCED AT ALL SITES...ESPECIALLY BY DAWN
ON TUESDAY. CEILINGS AND VISIBILITIES MAY GRADUALLY IMPROVE DURING
THE DAY...BUT IT SEEMS LIKELY THAT IFR CONDITIONS WILL REMAIN
INTACT BY 18Z.
EXTENDED DISCUSSION...
ABUNDANT LOW LEVEL MOISTURE IN A COOL WEDGE EAST OF THE BLUE
RIDGE ALONG WITH OVERRUNNING WARM AIR ADVECTION WILL RESULT IN
IFR CONDITIONS ON TUESDAY AFTERNOON. SOME IMPROVEMENT TO MVFR IS
POSSIBLE LATE IN THE DAY. A STRONG COLD FRONT SHOULD ARRIVE ON
WEDNESDAY...AND IT PROMISES TO BRING IFR/MVFR CONDITIONS AND A
PERIOD OF MODERATE RAIN. BY THURSDAY...HIGH PRESSURE WILL BUILD
OVERHEAD TO PROVIDE COLDER AND DRIER CONDITIONS...AND ALSO PROVIDE
A RECOVERY TO VFR CONDITIONS AT ALL TAF SITES.
&&
.EQUIPMENT...
AS OF 1111 AM EST MONDAY...
MAINTENANCE IS STILL ONGOING WITH THE KFCX RADAR EVEN THOUGH IT IS
OPERATIONAL NOW. TECHNICIANS ARE INVESTIGATING THE PROBLEM...BUT
THERE IS NO KNOWN TIME OF FULL RESTORATION AT THIS MOMENT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...PW
NEAR TERM...PW/WP
SHORT TERM...RCS
LONG TERM...PM
AVIATION...AMS/PW
EQUIPMENT...PW
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
300 PM CST MON FEB 1 2016
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 300 PM CST MON FEB 1 2016
CONTINUE TO FOCUS ON THE UPCOMING WINTER STORM AND ITS IMPACT ON
THE LOCAL AREA. FROM A FORCING STANDPOINT....THE 01.12Z MODELS
HAVE NOT SHOWN MUCH CHANGE. STILL EXPECTING A ROUND OF STRONG PV
ADVECTION IN THE 500-300 MB TO COME ACROSS THE REGION TUESDAY
AFTERNOON AND EVENING ALONG WITH STRONG AND DEEP QG CONVERGENCE IN
THE 1000-300 MB LAYER. THE MODELS HAVE INCREASED THE AMOUNT OF
AGEOSTROPHIC FORCING FOR TUESDAY AFTERNOON FROM THE DIVERGENCE
AHEAD OF THE LEFT EXIT REGION OF THE UPPER LEVEL JET. THE MODELS
DO SUGGEST THE FRONTOGENESIS WITH THIS SYSTEM MAY NOW BE A LITTLE
BIT MORE DISJOINTED. A BAND OF STRONG FRONTOGENESIS IN THE 750-550
MB LAYER WILL LIKELY MOVE THROUGH IN THE AFTERNOON ASSOCIATED WITH
THE MAIN PUSH OF WARM AIR ADVECTION AHEAD OF THE SYSTEM. A
SECONDARY AND SOMEWHAT WEAKER BAND THEN DEVELOPS DURING THE LATE
AFTERNOON AND EVENING IN THE DEFORMATION ZONE ON THE NORTHWEST
SIDE OF THE SURFACE LOW. THE DENDRITIC GROWTH ZONE STILL DOES NOT
LOOK TO BE HUGE WITH THIS SYSTEM...ON THE ORDER OF 50 TO 100
MB...BUT THE LIFT THROUGH THIS ZONE CONTINUES TO LOOK TO BE VERY
STRONG TO HELP PRODUCE THE SNOW. THIS STILL POINTS TO A BAND OF 8
TO AS MUCH OF 12 INCHES FALLING FROM THE WESTERN SECTIONS OF THE
AREA NORTHEAST INTO NORTH CENTRAL WISCONSIN.
THE TWO THINGS THAT HAVE CHANGED WITH THE LATEST MODEL DATA IS A
SHIFT TO THE NORTHWEST OF THE TRACK OF THE SURFACE LOW. THIS NOW
LOOKS TO COME OUT OF NORTHERN MISSOURI LATE TUESDAY
AFTERNOON...MOVE ACROSS EASTERN IOWA TUESDAY EVENING INTO
SOUTHEAST WISCONSIN LATE TUESDAY NIGHT. THIS SHIFT IN THE TRACK
PUSHES THE BAND OF HIGHEST SNOWFALL FARTHER TO THE NORTHWEST AS
WELL WITH THE GREATEST TOTALS NOW EXPECTED MAINLY NORTHWEST OF A
LINE FROM CHARLES CITY IOWA TO ABOUT SPARTA WISCONSIN OR SO. THE
OTHER IMPACT WILL BE TO BRING IN THE WARM TEMPERATURES ALOFT MORE
INTO THE AREA ALONG WITH THE POSSIBLE INTRODUCTION OF A LOSS OF
ICE. WORKING THIS DATA INTO THE FORECAST RESULTS IN MORE OF A
POSSIBILITY OF WINTRY MIX OVER NORTHEAST IOWA INTO SOUTHWEST
WISCONSIN WHICH CUTS DOWN ON THE SNOW AMOUNTS IN THAT AREA BUT
INTRODUCES MORE OF A POTENTIAL FOR SOME ICE ACCUMULATIONS. THIS
WILL HAVE TO BE WATCH CLOSELY AS THE EVENT UNFOLDS FOR FURTHER
REFINEMENTS.
A SECONDARY SHORT WAVE TROUGH IS NOW SHOWN BY THE MODELS TO TRAIL
BEHIND THE MAIN SYSTEM. THIS WAVE LOOKS TO COME ACROSS THE AREA
LATE TUESDAY NIGHT INTO WEDNESDAY MORNING. WHILE THIS SHOULD NOT
HAVE MUCH OVERALL IMPACT ON THE AREA...IT WILL SERVE TO MAINTAIN
THE LIGHT SNOW LONGER. INCREASED THE SNOW CHANCES FOR THE LATE
TUESDAY NIGHT HOURS INTO THE 50 TO 70 PERCENT RANGE AND THEN HELD
ONTO 50 PERCENT OR HIGHER ACROSS THE EASTERN SECTION WEDNESDAY
MORNING WITH A 20 TO 40 PERCENT CHANCE ELSEWHERE.
NO CHANGES PLANNED TO THE CURRENT HEADLINES. WILL MAINTAIN THE
WINTER STORM WARNING FOR THE ENTIRE AREA. STILL EXPECTING SOME
BLOWING AND DRIFTING TO OCCUR...BUT WITH THE LOW COMING FARTHER TO
THE NORTHWEST...THE AXIS OF HIGHER WINDS WILL BE PUSHED TO THE
NORTHWEST AS WELL...SO NOT ANTICIPATING ANY PROLONGED PERIODS OF
LOW VISIBILITIES FROM THE BLOWING SNOW. STILL THINK THERE WILL BE
PERIODS OF LOW VISIBILITIES BUT THESE SHOULD BE TIED MORE TO WHEN
THE WINDS GUSTS OCCUR VERSUS BEING TIED TO THE SUSTAINED WINDS.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 300 PM CST MON FEB 1 2016
STILL LOOKING AT NORTHWEST FLOW SETTING UP BEHIND THIS SYSTEM WITH
A SHORT WAVE TROUGH DROPPING ACROSS THE REGION THURSDAY. WITH THE
MAIN SNOW STORM LINGERING LONGER THAN EXPECTED...THIS NEXT WAVE
WILL HAVE EVEN LESS MOISTURE TO WORK...SO IT MAY ONLY BE ABLE TO
SQUEEZE OUT SOME LIGHT SNOW ACROSS THE NORTHERN SECTIONS. ANOTHER
SHORT WAVE TROUGH IN THIS NORTHWEST FLOW THEN LOOKS TO COME ACROSS
THE REGION FRIDAY AND FRIDAY NIGHT. THIS SYSTEM WILL HAVE THE
POTENTIAL TO PRODUCE SOME MORE LIGHT SNOW ACROSS THE NORTHERN AND
EASTERN SECTIONS. A THIRD AND STRONGEST SHORT WAVE TROUGH IN THIS
NORTHWEST FLOW THEN IS EXPECTED TO COME ACROSS FOR THE END OF THE
WEEKEND INTO EARLY NEXT WEEK. THIS WAVE SHOULD HAVE A BETTER
CHANCE OF PRODUCING SOME LIGHT SNOW FOR THE ENTIRE AREA AND WILL
CARRY SOME 30 PERCENT CHANCES WITH THIS SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1149 AM CST MON FEB 1 2016
KAAL WEB CAM IS SHOWING THAT THE CEILING HAS BEEN RISING OUT OF
THE ZUMBRO RIVER VALLEY DURING THE PAST COUPLE OF HOURS...AND THIS
IS EXPECTED TO CONTINUE TO RISE AND DISSIPATE THIS AFTERNOON. AS A
RESULT...WE EXPECT THAT THE DENSE FOG AT KRST WILL QUICKLY
DISSIPATE BY 01.19Z.
LIKE YESTERDAY...THE NAM AND RAP CONTINUE TO SHOW TOO MUCH LOW
LEVEL MOISTURE BELOW 2K FEET...THEREFORE...TRENDED THE TAF
FORECAST MORE TOWARD THE GFS. WITH THIS IN MIND...THERE ARE VFR
CEILINGS AND VISIBILITIES THROUGH 02.10Z AND THEN EXPECT A MVFR
VISIBILITY TO DEVELOP DUE TO FOG.
ON TUESDAY MORNING...THE SOUNDINGS CONTINUE TO SHOW THAT THE SNOW
WILL QUICKLY DEVELOP LIFR CEILINGS AND VISIBILITIES AT KRST BETWEEN
02.13Z AND 02.14Z...AND AT KLSE BETWEEN 02.14Z AND 02.15Z. HOURLY
SNOW RATES UP TO 2 INCHES AN HOUR LOOK POSSIBLE FOR KRST...AND
MAYBE UP TO AN INCH AN HOUR AT KLSE BETWEEN 02.15Z AND 03.00Z.
TOTAL SNOWFALL BY NOON WILL BE AROUND 4 INCHES AT BOTH TAF SITES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING FROM 3 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
WIZ053>055-061.
WINTER STORM WARNING FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
WIZ017-029-032>034-041>044.
MN...WINTER STORM WARNING FROM 3 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
MNZ094>096.
WINTER STORM WARNING FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
MNZ079-086>088.
IA...WINTER STORM WARNING FROM 3 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1149 AM CST MON FEB 1 2016
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 304 AM CST MON FEB 1 2016
OBVIOUSLY THE FOCUS IN THE SHORT TERM IS THE ONSET OF THE WINTER
STORM WE HAVE BEEN TALKING ABOUT FOR SEVERAL DAYS NOW. THE STORM
COMPLEX THAT WILL BRING OUR WINTRY FUN WAS SPINNING OVER THE
DESERT SOUTHWEST AT 08Z AND WILL BE CROSSING THE ROCKIES THIS
MORNING. BY EVENING...THE STORM WILL BE ZIPPING ACROSS KS...AND
SHOULD MAKE IT TO THE CHICAGO/MILWAUKEE AREA BY TUESDAY EVENING.
THIS VERY DYNAMIC SYSTEM IS MOVING RATHER QUICKLY...BUT THE
IMPRESSIVE AMOUNT OF LIFT BEING GENERATED WILL LEAD TO SNOWFALL
RATES THAT SHOULD OFFSET THE SPEED.
THE AREA WILL START OUT WITH PARTLY CLOUDY SKIES...THANKS TO THE
PASSAGE OF A COUPLE OF WEAK SHORT WAVES MOVING THROUGH THE AREA ON
FAST NORTHWEST FLOW. THESE CLOUDS WILL HAVE AN IMPACT ON THE
TEMPERATURE POTENTIAL. FULL SUN THE PAST TWO DAYS ALLOWED FOR SOME
BALMY TEMPS FOR LATE JANUARY. AND CONCERNED TODAY COULD ALSO BE
WARMER THAN GUIDANCE IF THE CLOUDS HOLD OFF. DID INCREASE HIGH
TEMPS TODAY...ESPECIALLY GIVEN THE RELATIVELY WARM START.
THE LEADING EDGE OF THE SNOW SHOULD MAKE IT TO IA BY EVENING...AND
IS EXPECTED TO REACH NORTHEAST IA AND SOUTHWEST WI SHORTLY AFTER
MIDNIGHT. BUT THE LARGER SCALE SNOWS WILL START TUESDAY MORNING
WITH THE HEAVIEST SNOW FALLING DURING THE AFTERNOON AND INTO THE
EVENING. THE LIFT SEEN IS IMPRESSIVE WITH THE DIFLUENCE ALOFT AND
STRONG UPPER JET. CONVECTIVELY UNSTABLE LAYERS ALSO SEEN IN THE
BUFKIT FORECAST SOUNDINGS. LOOKING AT NEARLY AN INCH OF LIQUID
WATER AVAILABLE WITH THIS...SO SIGNIFICANT SNOW AMOUNTS APPEAR
LIKELY.
AS HAS BEEN MENTIONED FOR SEVERAL DAYS NOW...THERE HAS BEEN SOME
UNCERTAINTY ON THE EXACT TRACK OF THE SYSTEM AND WHERE THE
HEAVIEST SNOW BAND WILL SET UP. BUT THE VARIOUS COMPUTER MODEL
SIMULATIONS HAVE BEEN REMARKABLY CLOSE ON PLACEMENT...WITH ONLY
VERY MINOR SHIFTS. THE TREND OVER THE PAST FEW RUNS HAS BEEN FOR A
BIT FASTER ONSET AND END...WITH PERHAPS A SLIGHT NORTHWARD JOG.
BUT OVERALL IT APPEARS OUR FORECAST REMAINS SQUARELY IN THE PATH
FOR THE HEAVIEST AMOUNTS...WITH AMOUNTS OF 6 TO AS MUCH AS 11
INCHES EXPECTED. WITH THAT IN MIND...WE HAVE DECIDED IT IS TIME TO
UPGRADE TO WARNINGS AT THIS TIME. THE FINAL CONCERN IS THE
POTENTIAL FOR WIND TO CAUSE BLIZZARD CONDITIONS. WE WILL BE SEEING
WIND GUSTS UP AROUND 30 MPH TUESDAY AFTERNOON AND EVENING ACROSS
THE OPEN AREAS OF SOUTHERN MN AND NORTHERN IA. THIS WILL LIKELY
MOVE SOME SNOW AROUND...WITH DRIFTING AND LOCALIZED BLOWING SNOW
AND SOME REDUCED VISIBILITY. BUT NOT SOLD THAT THIS WILL BE ENOUGH
TO ACTUALLY WARRANT A BLIZZARD HEADLINE. USE OF LOCAL BLOWING SNOW
TOOLS SUPPORT ONLY LIMITED IMPACTS...SO AFTER MULLING OVER THE
IDEA...HAVE DECIDED TO GO WITH A WINTER STORM WARNING EVERYWHERE
AND NOT UTILIZE ANY BLIZZARD HEADLINES.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 304 AM CST MON FEB 1 2016
THE STORM SYSTEM MOVES AWAY TUESDAY NIGHT...WITH ONLY LINGERING
LIGHT SNOW OVER EASTERN WI EARLY WEDNESDAY. THE AREA REMAINS IN
BROAD LONG WAVE TROUGHING...WITH WEAK DISTURBANCES OCCASIONALLY
DROPPING IN. THE FIRST MAY BRING A LITTLE LIGHT SNOW THURSDAY TO
AREAS ALONG AND NORTH OF I-94. ANOTHER SHORT WAVE TROUGH COMES IN
FOR FRIDAY NIGHT INTO SATURDAY...BRINGING ANOTHER CHANCE FOR LIGHT
SNOW. TEMPERATURES WILL BE ON A BIT OF A ROLLER COASTER. BEHIND
OUR DEPARTING STORM...EXPECT LOWS TO DROP INTO THE SINGLE DIGITS
THURSDAY MORNING. BUT THEN SOUTHERLY WINDS AHEAD OF THE 2ND
DISTURBANCE WILL ALLOW HIGHS TO GET WELL INTO THE 20S. THEN A DIP
BACK INTO THE SINGLE DIGITS BEFORE SOUTH WINDS RETURN TO BACK UP
CLOSER TO 30.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1149 AM CST MON FEB 1 2016
KAAL WEB CAM IS SHOWING THAT THE CEILING HAS BEEN RISING OUT OF
THE ZUMBRO RIVER VALLEY DURING THE PAST COUPLE OF HOURS...AND THIS
IS EXPECTED TO CONTINUE TO RISE AND DISSIPATE THIS AFTERNOON. AS A
RESULT...WE EXPECT THAT THE DENSE FOG AT KRST WILL QUICKLY
DISSIPATE BY 01.19Z.
LIKE YESTERDAY...THE NAM AND RAP CONTINUE TO SHOW TOO MUCH LOW
LEVEL MOISTURE BELOW 2K FEET...THEREFORE...TRENDED THE TAF
FORECAST MORE TOWARD THE GFS. WITH THIS IN MIND...THERE ARE VFR
CEILINGS AND VISIBILITIES THROUGH 02.10Z AND THEN EXPECT A MVFR
VISIBILITY TO DEVELOP DUE TO FOG.
ON TUESDAY MORNING...THE SOUNDINGS CONTINUE TO SHOW THAT THE SNOW
WILL QUICKLY DEVELOP LIFR CEILINGS AND VISIBILITIES AT KRST BETWEEN
02.13Z AND 02.14Z...AND AT KLSE BETWEEN 02.14Z AND 02.15Z. HOURLY
SNOW RATES UP TO 2 INCHES AN HOUR LOOK POSSIBLE FOR KRST...AND
MAYBE UP TO AN INCH AN HOUR AT KLSE BETWEEN 02.15Z AND 03.00Z.
TOTAL SNOWFALL BY NOON WILL BE AROUND 4 INCHES AT BOTH TAF SITES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING FROM 3 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
WIZ053>055-061.
WINTER STORM WARNING FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
WIZ017-029-032>034-041>044.
MN...WINTER STORM WARNING FROM 3 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
MNZ094>096.
WINTER STORM WARNING FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
MNZ079-086>088.
IA...WINTER STORM WARNING FROM 3 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...MW
LONG TERM...MW
AVIATION...BOYNE