Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/01/15
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
250 PM MST FRI JAN 30 2015
.UPDATE...UPDATED AVIATION WEATHER DISCUSSION.
&&
.SYNOPSIS...
SHOWERS WILL CONTINUE TO BE LIKELY OVER SOUTH-CENTRAL ARIZONA
TONIGHT...ESPECIALLY THE HIGHER TERRAIN...LESS LIKELY OVER SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA. RAIN CHANCES CONTINUE SATURDAY
BEFORE DIMINISHING SATURDAY NIGHT. SNOW LEVELS WILL REMAIN
HIGH...LOWERING TO AROUND 7000-7500 FEET BY SATURDAY MORNING. DRY
WEATHER AND A SLOW WARMING TREND BEGINS SUNDAY AND CONTINUES THROUGH
NEXT WEEK.
&&
.DISCUSSION...
REST OF TODAY THROUGH SATURDAY...
MAIN BAND OF PRECIP AS OF MID AFTERNOON HAS BEEN OVER PORTIONS OF
GILA...PINAL...AND NORTHEAST MARICOPA COUNTY WHERE A FLOOD ADVISORY
WAS IN EFFECT...INCLUDED FAR EAST PORTIONS OF THE METRO. THIS
APPEARS TO BE ASSOCIATED WITH AN AREA OF UPPER LEVEL DIVERGENCE.
LESSER SHOWERS HAVE CONTINUED OVER THE REST OF THE PHOENIX AREA WITH
LITTLE TO NO ACTIVITY OVER SOUTHWEST ARIZONA AND SOUTHEAST
CALIFORNIA. MODEL CAPE STILL LOOKS QUITE MODEST BUT HELD ON TO
SLIGHT CHANCES FOR THUNDERSTORMS FOR THE REST OF THIS AFTERNOON AND
EARLY EVENING. AS THE SYSTEM SLOWLY SHIFTS EASTWARD...SHOWERS SHOULD
START TO TREND DOWNWARD. HOWEVER...THERE IS ANOTHER VORT MAX OVER
SONORA WHICH MAY BRUSH EASTERN PORTIONS OF THE AREA AND KEEP SOME
SHOWER ACTIVITY GOING. RAP SHOWS A SEPARATE SMALLER VORT MAX MOVING
NORTHEASTWARD FROM NORTHERN BAJA INTO OUR FORECAST AREA FOR A
RESUMPTION OF LIGHT RAIN IN OUR WESTERN AREAS. THUS HELD ON TO POPS
FOR TONIGHT...LOWER NUMBERS WESTERN AREAS. OF NOTE...MOST MODELS
INDICATE THE BRUNT OF THE SONORA VORT MAX TRACKING EAST OF THE
PHOENIX AREA. YET ANOTHER VORT MAX ROUNDS THE BOTTOM OF THE UPPER
TROUGH LATE TONIGHT AND BEGINS AFFECTING SOUTHERN ARIZONA SATURDAY
MORNING. LOOKS LIKE SOUTHEAST ARIZONA WILL SEE MOST OF THE PRECIP
FROM THAT FEATURE BUT DEPICT SOME NOTABLE QPF SPREADING WELL INTO
SOUTH-CENTRAL ARIZONA. THUS WE MAY HAVE ANOTHER ROUND OF WIDESPREAD
SHOWERS BEFORE A DOWNTREND BEGINS IN THE AFTERNOON.
OVERALL...ANTICIPATE LESS DYNAMICAL LIFT TONIGHT AND SATURDAY
COMPARED TO THE PREVIOUS 24 HOURS...DUE AT LEAST IN PART TO LOSS OF
UPPER DIFFLUENCE/DIVERGENCE. ACCORDINGLY...ANTICIPATE LESS PRECIP
TONIGHT AND SATURDAY THAN WE HAD IN THE PRECEDING 24 HOURS.
ANTICIPATE NUISANCE FLOODING TO CONTINUE...MAINLY OVER HIGHER
TERRAIN AND FOOTHILL AREAS...LESS OVER VALLEY FLOORS OF THE CENTRAL
DESERTS. ONE CAVEAT IS THAT WE COULD HAVE A LITTLE BIT MORE
INSTABILITY IF CLOUDS THIN OUT ENOUGH. NAM HAS BEEN DEPICTING THIS
IDEA. THUS HELD ON TO SLIGHT CHANCE OF THUNDERSTORMS FOR SATURDAY
AFTERNOON. THE SYSTEM BEGINS EXITING SOUTHWARD SATURDAY NIGHT AS A
RIDGE BUILDS IN AND THUS POPS DIMINISH OVERNIGHT SATURDAY.
SUNDAY THROUGH FRIDAY...
SUNDAY LOOKS TO BE A DRY AND WARMER DAY. PATCHY MORNING FOG IS A
POSSIBILITY BUT THERE MAY BE ENOUGH LINGERING CLOUDS TO HINDER THE
RADIATIONAL COOLING NECESSARY. PARED BACK ON THE AREAL COVERAGE TO
REMOVE SOUTHEAST CALIFORNIA AND THE LOWER COLORADO RIVER VALLEY AS
SOME DRY ADVECTION MOVES IN THERE. THE RIDGE SLOWLY BUILDS INTO THE
WEST MONDAY THROUGH THURSDAY FOR A GRADUAL WARMING TREND...AND WE
CAN EXPECT DESERT HIGHS TO REACH BACK INTO THE LOW TO MID 70S BY
NEXT WEDNESDAY...WITH THE WARMER WESTERN DESERTS RISING TO NEAR 80
BY NEXT THURSDAY...LITTLE CHANGE FRIDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...
BROAD UPPER LOW CENTER WILL CONTINUE OVER THE REGION THROUGH
SATURDAY EVENING. THROUGH 08Z SAT...MVFR CIGS AND VSBYS...MEANING
CIGS BETWEEN 15 HUNDRED AND 3 THSD FT AGL...AND VSBYS 3-5 MI WITH
SCT LGT SHWRS. FROM 08Z SAT TO 14Z SAT...RAIN INCREASING. CIGS AND
VSBYS OCNL IFR...MEANING 7-12 HUNDRED FT AGL AND VSBYS NEAR 2
MILES...HOWEVER WIDESPREAD MVFR CONDITIONS.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THROUGH 14Z SAT...CIGS 5-7 THSD AGL...ISOLD LGT SHWR.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
DRIER AND SIGNIFICANTLY WARMER WEATHER IS EXPECTED...AS HIGH
PRESSURE BEGINS BUILDING BACK INTO THE REGION. HIGH TEMPERATURES IN
THE LOWER DESERTS WILL START OUT IN THE UPPER 60S ON SUNDAY AND
GRADUALLY CLIMB INTO THE UPPER 70S BY THURSDAY. WINDS ARE EXPECTED
TO BE LIGHT AND VARIABLE FOR MOST OF THE FORECAST PERIOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ/CB
AVIATION...VASQUEZ
FIRE WEATHER...MCLANE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
240 PM MST FRI JAN 30 2015
.SYNOPSIS...
SHOWERS WILL CONTINUE TO BE LIKELY OVER SOUTH-CENTRAL ARIZONA
TONIGHT...ESPECIALLY THE HIGHER TERRAIN...LESS LIKELY OVER SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA. RAIN CHANCES CONTINUE SATURDAY
BEFORE DIMINISHING SATURDAY NIGHT. SNOW LEVELS WILL REMAIN
HIGH...LOWERING TO AROUND 7000-7500 FEET BY SATURDAY MORNING. DRY
WEATHER AND A SLOW WARMING TREND BEGINS SUNDAY AND CONTINUES THROUGH
NEXT WEEK.
&&
.DISCUSSION...
REST OF TODAY THROUGH SATURDAY...
MAIN BAND OF PRECIP AS OF MID AFTERNOON HAS BEEN OVER PORTIONS OF
GILA...PINAL...AND NORTHEAST MARICOPA COUNTY WHERE A FLOOD ADVISORY
WAS IN EFFECT...INCLUDED FAR EAST PORTIONS OF THE METRO. THIS
APPEARS TO BE ASSOCIATED WITH AN AREA OF UPPER LEVEL DIVERGENCE.
LESSER SHOWERS HAVE CONTINUED OVER THE REST OF THE PHOENIX AREA WITH
LITTLE TO NO ACTIVITY OVER SOUTHWEST ARIZONA AND SOUTHEAST
CALIFORNIA. MODEL CAPE STILL LOOKS QUITE MODEST BUT HELD ON TO
SLIGHT CHANCES FOR THUNDERSTORMS FOR THE REST OF THIS AFTERNOON AND
EARLY EVENING. AS THE SYSTEM SLOWLY SHIFTS EASTWARD...SHOWERS SHOULD
START TO TREND DOWNWARD. HOWEVER...THERE IS ANOTHER VORT MAX OVER
SONORA WHICH MAY BRUSH EASTERN PORTIONS OF THE AREA AND KEEP SOME
SHOWER ACTIVITY GOING. RAP SHOWS A SEPARATE SMALLER VORT MAX MOVING
NORTHEASTWARD FROM NORTHERN BAJA INTO OUR FORECAST AREA FOR A
RESUMPTION OF LIGHT RAIN IN OUR WESTERN AREAS. THUS HELD ON TO POPS
FOR TONIGHT...LOWER NUMBERS WESTERN AREAS. OF NOTE...MOST MODELS
INDICATE THE BRUNT OF THE SONORA VORT MAX TRACKING EAST OF THE
PHOENIX AREA. YET ANOTHER VORT MAX ROUNDS THE BOTTOM OF THE UPPER
TROUGH LATE TONIGHT AND BEGINS AFFECTING SOUTHERN ARIZONA SATURDAY
MORNING. LOOKS LIKE SOUTHEAST ARIZONA WILL SEE MOST OF THE PRECIP
FROM THAT FEATURE BUT DEPICT SOME NOTABLE QPF SPREADING WELL INTO
SOUTH-CENTRAL ARIZONA. THUS WE MAY HAVE ANOTHER ROUND OF WIDESPREAD
SHOWERS BEFORE A DOWNTREND BEGINS IN THE AFTERNOON.
OVERALL...ANTICIPATE LESS DYNAMICAL LIFT TONIGHT AND SATURDAY
COMPARED TO THE PREVIOUS 24 HOURS...DUE AT LEAST IN PART TO LOSS OF
UPPER DIFFLUENCE/DIVERGENCE. ACCORDINGLY...ANTICIPATE LESS PRECIP
TONIGHT AND SATURDAY THAN WE HAD IN THE PRECEDING 24 HOURS.
ANTICIPATE NUISANCE FLOODING TO CONTINUE...MAINLY OVER HIGHER
TERRAIN AND FOOTHILL AREAS...LESS OVER VALLEY FLOORS OF THE CENTRAL
DESERTS. ONE CAVEAT IS THAT WE COULD HAVE A LITTLE BIT MORE
INSTABILITY IF CLOUDS THIN OUT ENOUGH. NAM HAS BEEN DEPICTING THIS
IDEA. THUS HELD ON TO SLIGHT CHANCE OF THUNDERSTORMS FOR SATURDAY
AFTERNOON. THE SYSTEM BEGINS EXITING SOUTHWARD SATURDAY NIGHT AS A
RIDGE BUILDS IN AND THUS POPS DIMINISH OVERNIGHT SATURDAY.
SUNDAY THROUGH FRIDAY...
SUNDAY LOOKS TO BE A DRY AND WARMER DAY. PATCHY MORNING FOG IS A
POSSIBILITY BUT THERE MAY BE ENOUGH LINGERING CLOUDS TO HINDER THE
RADIATIONAL COOLING NECESSARY. PARED BACK ON THE AREAL COVERAGE TO
REMOVE SOUTHEAST CALIFORNIA AND THE LOWER COLORADO RIVER VALLEY AS
SOME DRY ADVECTION MOVES IN THERE. THE RIDGE SLOWLY BUILDS INTO THE
WEST MONDAY THROUGH THURSDAY FOR A GRADUAL WARMING TREND...AND WE
CAN EXPECT DESERT HIGHS TO REACH BACK INTO THE LOW TO MID 70S BY
NEXT WEDNESDAY...WITH THE WARMER WESTERN DESERTS RISING TO NEAR 80
BY NEXT THURSDAY...LITTLE CHANGE FRIDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...
PERIODS OF RAIN WILL CONTINUE THROUGH 20Z WITH OCCASIONAL IFR CIGS
AND VSBYS AS A WEATHER DISTURBANCE MOVES THROUGH THE AREA FROM THE
SOUTH. IN THE WAKE OF THE WEATHER DISTURBANCE...CIGS SHOULD LIFT TO
BETWEEN 25-35 HUNDRED FT (WIDESPREAD MVFR) WITH VSBYS BETWEEN 3-5
MILES AS RAIN DIMINISHES TO LIGHT SCT SHWRS. MVFR CONDITIONS WILL
CONTINUE OVERNIGHT FRIDAY...HOWEVER ANOTHER BOUT OF RAIN IS EXPECTED
SATURDAY MORNING WITH WIDESPREAD MVFR AND OCCASIONAL IFR CONDITIONS
IN CIGS/VSBYS (BETWEEN 10Z AND 17Z SAT).
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
WIDESPREAD CIGS BETWEEN 6-8 THSD AGL WITH ISOLATED RAIN SHWRS
THROUGH 12Z SAT.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
DRIER AND SIGNIFICANTLY WARMER WEATHER IS EXPECTED...AS HIGH
PRESSURE BEGINS BUILDING BACK INTO THE REGION. HIGH TEMPERATURES IN
THE LOWER DESERTS WILL START OUT IN THE UPPER 60S ON SUNDAY AND
GRADUALLY CLIMB INTO THE UPPER 70S BY THURSDAY. WINDS ARE EXPECTED
TO BE LIGHT AND VARIABLE FOR MOST OF THE FORECAST PERIOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ/CB
AVIATION...VASQUEZ
FIRE WEATHER...MCLANE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1140 AM MST FRI JAN 30 2015
.UPDATE...UPDATED AVIATION WEATHER DISCUSSION.
&&
.SYNOPSIS...
A PACIFIC LOW PRESSURE SYSTEM WILL LEAD TO A SIGNIFICANT RAIN EVENT
ACROSS THE REGION TODAY AND CONTINUING INTO SATURDAY. WE ANTICIPATE
RAINFALL TO BE MOST WIDESPREAD TODAY WITH MORE HIT AND MISS
SHOWERS ON SATURDAY. SNOW LEVELS WILL REMAIN HIGH...LOWERING TO
AROUND 7000-7500 FEET BY SATURDAY MORNING. DRY WEATHER AND A SLOW
WARMING TREND BEGINS SUNDAY AND CONTINUES THROUGH NEXT THURSDAY.
&&
.DISCUSSION...
COVERAGE OF SHOWERS THIS MORNING HAS TRENDED DOWN OVER SOUTHWEST
ARIZONA AND SOUTHEAST CALIFORNIA. ACTIVITY HAS ALSO BECOME LESS
WIDESPREAD OVER METRO PHOENIX BUT REMAINS MORE WIDESPREAD OVER GILA
COUNTY. THE DOWNTREND LOOKS TO BE ASSOCIATED WITH THE EXIT OF A VORT
MAX NOW CENTERED ROUGHLY NEAR THE CAL-NEV-ARI BORDERS. THE MAIN
UPPER TROUGH IS CHANGING SHAPE DUE TO THE VARIOUS VORT LOBES
DUMBELLING AROUND. OTHER AREAS OF INTEREST WITHIN THE TROUGH INCLUDE
THE SOUTHERN END NEAR/WEST OF THE BAJA SPUR AND ANOTHER LOBE/VORT
MAX CENTERED ALONG THE CENTRAL CALIFORNIA COAST. THERE MAY BE
ANOTHER VORT MAX TO MOVE THROUGH THE FORECAST AREA LATER
TODAY/TONIGHT BUT OVERALL...THE PREVIOUSLY MENTIONED VORT LOBES WILL
LARGELY MISS OUR FORECAST AREA FOR THE DURATION OF THE EVENT...PER
LATEST MODELS. HOWEVER...DYNAMICAL FORCING WILL CONTINUE TO AFFECT
SOUTHEAST ARIZONA AND ADVECTION OF THOSE SHOWERS INTO OUR AREA MAY
OCCUR SATURDAY MORNING. AS FOR THUNDERSTORM POTENTIAL...MODEL CAPE
FOR THIS AFTERNOON CONTINUES TO LOOK QUITE MEAGER FROM THE GFS AND
BETTER FROM THE NAM. RAP IS EVEN BETTER THAN THE NAM BUT STILL UNDER
200 J/KG. HRRR SHOWS SOME ISOLATED WEAK CONVECTION AS WELL. THUS
WILL HOLD ON THE SLIGHT CHANCES. NAM SHOWS A NOTABLE INCREASE IN
CAPE FOR SATURDAY WHILE THE GFS IS STILL MEAGER. AS FOR CHANGES TO
THE FORECAST IN THE SHORT TERM...MAY NEED TO MAKE SOME DOWNWARD
ADJUSTMENTS TO POPS...MORE NOTICEABLY IN OUR WESTERN AREAS. MORE
LATER.
&&
.PREVIOUS DISCUSSION ISSUED 255 AM MST/155 AM PST...
AT 2 AM...VIGOROUS UPPER LEVEL LOW CONTINUED TO SPIN JUST OFF THE
NRN BAJA COAST...SPREADING COPIOUS AMOUNTS OF MOISTURE NORTHWARD
INTO ARIZONA AND PORTIONS OF FAR SERN CA. CURRENT BLENDED TOTAL
PRECIP WATER IMAGERY SHOWED 1.25-1.5 INCHES OF PWAT MOVING NORTH
ACROSS CENTRAL BAJA...POISED TO MOVE NORTH INTO ARIZONA DURING THE
DAY TODAY. IR IMAGERY AT 2 AM SHOWED AN IMPRESSIVE STREAM OF CLOUDS
OVERSPREADING THE AREA FROM THE SOUTH...AND THE LATEST 1.3 DEG RADAR
LOOP SHOWED WIDESPREAD SHOWERS SPREADING NORTH ACROSS MUCH OF
CENTRAL/SOUTH CENTRAL AZ WITH AREAL COVERAGE VIRTUALLY 100 PERCENT.
OVER THE PAST 6 HOURS...VIRTUALLY EVERY MARICOPA COUNTY FLOOD
CONTROL DISTRICT GAGE HAS PICKED UP MEASURABLE RAIN...WITH MOST
TOTALS BETWEEN ONE TENTH AND ONE THIRD OF AN INCH. PHOENIX HAS
PICKED UP 0.36 INCHES SO FAR WITH THIS EVENT...AND THE PERIODS OF
EXPECTED HEAVIEST RAINFALL HAVE YET TO OCCUR.
MODEL GUIDANCE HAS BEEN REMARKABLY CONSISTENT OVER THE PAST FEW DAYS
REGARDING THE EVOLUTION OF THIS WET WEATHER SYSTEM...INCLUDING
DETAILS SUCH AS TIMING AND QPF AMOUNTS. ALL GUIDANCE CALLS FOR AN
UPPER CLOSED LOW TO FORM OVER FAR SERN CA BY LATER THIS AFTERNOON...
AND AS THE LOW SPINS UP THE MOST SIGNIFICANT PRECIP IS EXPECTED TO
OCCUR OVER THE AREA...ESPECIALLY ACROSS SOUTH CENTRAL AZ. POPS WILL
STAY VERY HIGH TODAY...LIKELY OUT WEST AND CATEGORICAL OVER OUR
EASTERN FORECAST ZONES...WITH BASICALLY A 100 PERCENT CHANCE OF RAIN
CONTINUING FOR THE GREATER PHOENIX AREA. QPF AMOUNTS SHOULD RANGE
BETWEEN ONE QUARTER AND ONE HALF INCH TODAY ACROSS SOUTH CENTRAL
AZ...WITH LOCALLY HIGHER AMOUNTS OVER HIGHER TERRAIN AREAS TO THE
NORTH AND EAST OF PHOENIX. THERE WILL BE MODEST INSTABILITY OVER THE
CENTRAL DESERTS TODAY SO WE WILL CONTINUE TO CALL FOR A SLIGHT
CHANCE OF AFTN/EVE THUNDERSTORMS BASICALLY FROM THE LOWER CO RIVER
VALLEY EASTWARD. SHOULD A STORM DEVELOP...RAINFALL TOTALS WILL
BECOME ENHANCED. GIVEN ALL OF THE CLOUDS AND SHOWERS...HIGH TEMPS
TODAY WILL STAY WELL BELOW SEASONAL NORMALS WITH HIGHS OVER SOUTH
CENTRAL AZ TO HOVER IN THE UPPER 50S TO LOW 60S.
FOR TONIGHT THROUGH THE EVENING ON SATURDAY...THE UPPER LOW IS
PROGGED TO VERY SLOWLY TRANSLATE TO THE EAST/SOUTHEAST AND AS IT
DOES SO THERE WILL BE PERIODS OF ENHANCED LIFT/UVV AS VORT
SPOKES/LOBES ROTATE AROUND THE MAIN UPPER LOW. WITH MOISTURE OVER
THE LOWER DESERTS EXPECTED TO REMAIN VERY HIGH THROUGH SATURDAY...
PWAT VALUES REMAINING BETWEEN 0.75 AND 1.00 INCH...THE CONTINUED
DYNAMICS FROM THE VORT LOBES WILL KEEP SHOWERS GOING OVER MOST THE
REGION AND POPS WILL STAY ELEVATED. CHANCE TO LIKELY POPS WILL
REMAIN ACROSS SOUTH CENTRAL AZ TONIGHT AND SATURDAY...WITH POPS
DROPPING INTO THE SLIGHT CHANCE CATEGORY OVER SERN CA DURING THE DAY
ON SATURDAY.
OVERALL...WE ARE LOOKING AT STORM TOTAL AMOUNTS ENDING SATURDAY
EVENING RANGING FROM ONE QUARTER TO ONE HALF INCH OVER THE WESTERN
DESERTS...TO OVER ONE INCH ACROSS THE CENTRAL DESERTS INCLUDING THE
GREATER PHOENIX AREA. HIGHER AMOUNTS...1.25 TO NEARLY 2 INCHES...ARE
POSSIBLE IN THE HIGHER TERRAIN AREAS NORTH AND EAST OF PHOENIX. FOR
NOW WE EXPECT RAIN TO BE CONTINUAL AND NOT LOCALLY HEAVY OR INTENSE
ENOUGH TO WARRANT FLASH FLOODING CONCERNS. THERE MAY BE AREAS THAT
EXPERIENCE SOME URBAN OR SMALL STREAM FLOODING AS TIME WEARS ON AND
WE CAN SIMPLY ISSUE FLOOD ADVISORY PRODUCTS AS NEEDED TO COVER THIS
CONTINGENCY.
HIGH TEMPS SATURDAY WILL REMAIN WELL BELOW NORMAL AND WILL CHANGE
LITTLE FROM TODAYS EXPECTED READINGS. HIGHS SATURDAY IN THE GREATER
PHOENIX AREA WILL STAY IN THE UPPER 50S TO LOW 60S...NEARLY 10
DEGREES BELOW SEASONAL NORMALS.
SUNDAY THROUGH THURSDAY...
SUNDAY LOOKS TO BE A DRY AND WARMER DAY. PATCHY MORNING FOG IS A
POSSIBILITY BUT THERE MAY BE ENOUGH LINGERING CLOUDS TO HINDER THE
RADIATIONAL COOLING NECESSARY. THE RIDGE SLOWLY BUILDS INTO THE
WEST MONDAY THROUGH THURSDAY FOR A GRADUAL WARMING TREND...AND WE
CAN EXPECT DESERT HIGHS TO REACH BACK INTO THE LOW TO MID 70S BY
NEXT WEDNESDAY...WITH THE WARMER WESTERN DESERTS RISING TO NEAR 80
BY NEXT THURSDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...
PERIODS OF RAIN WILL CONTINUE THROUGH 20Z WITH OCCASIONAL IFR CIGS
AND VSBYS AS A WEATHER DISTURBANCE MOVES THROUGH THE AREA FROM THE
SOUTH. IN THE WAKE OF THE WEATHER DISTURBANCE...CIGS SHOULD LIFT TO
BETWEEN 25-35 HUNDRED FT (WIDESPREAD MVFR) WITH VSBYS BETWEEN 3-5
MILES AS RAIN DIMINISHES TO LIGHT SCT SHWRS. MVFR CONDITIONS WILL
CONTINUE OVERNIGHT FRIDAY...HOWEVER ANOTHER BOUT OF RAIN IS EXPECTED
SATURDAY MORNING WITH WIDESPREAD MVFR AND OCCASIONAL IFR CONDITIONS
IN CIGS/VSBYS (BETWEEN 10Z AND 17Z SAT).
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
WIDESPREAD CIGS BETWEEN 6-8 THSD AGL WITH ISOLATED RAIN SHWRS
THROUGH 12Z SAT.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
DRIER AND SIGNIFICANTLY WARMER WEATHER IS EXPECTED...AS HIGH
PRESSURE BEGINS BUILDING BACK INTO THE REGION. HIGH TEMPERATURES IN
THE LOWER DESERTS WILL START OUT IN THE UPPER 60S ON SUNDAY AND
GRADUALLY CLIMB INTO THE UPPER 70S BY THURSDAY. WINDS ARE EXPECTED
TO BE LIGHT AND VARIABLE FOR MOST OF THE FORECAST PERIOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...CB
AVIATION...VASQUEZ
FIRE WEATHER...MCLANE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
950 AM MST FRI JAN 30 2015
.SYNOPSIS...
A PACIFIC LOW PRESSURE SYSTEM WILL LEAD TO A SIGNIFICANT RAIN EVENT
ACROSS THE REGION TODAY AND CONTINUING INTO SATURDAY. WE ANTICIPATE
RAINFALL TO BE MOST WIDESPREAD TODAY WITH MORE HIT AND MISS
SHOWERS ON SATURDAY. SNOW LEVELS WILL REMAIN HIGH...LOWERING TO
AROUND 7000-7500 FEET BY SATURDAY MORNING. DRY WEATHER AND A SLOW
WARMING TREND BEGINS SUNDAY AND CONTINUES THROUGH NEXT THURSDAY.
&&
.DISCUSSION...
COVERAGE OF SHOWERS THIS MORNING HAS TRENDED DOWN OVER SOUTHWEST
ARIZONA AND SOUTHEAST CALIFORNIA. ACTIVITY HAS ALSO BECOME LESS
WIDESPREAD OVER METRO PHOENIX BUT REMAINS MORE WIDESPREAD OVER GILA
COUNTY. THE DOWNTREND LOOKS TO BE ASSOCIATED WITH THE EXIT OF A VORT
MAX NOW CENTERED ROUGHLY NEAR THE CAL-NEV-ARI BORDERS. THE MAIN
UPPER TROUGH IS CHANGING SHAPE DUE TO THE VARIOUS VORT LOBES
DUMBELLING AROUND. OTHER AREAS OF INTEREST WITHIN THE TROUGH INCLUDE
THE SOUTHERN END NEAR/WEST OF THE BAJA SPUR AND ANOTHER LOBE/VORT
MAX CENTERED ALONG THE CENTRAL CALIFORNIA COAST. THERE MAY BE
ANOTHER VORT MAX TO MOVE THROUGH THE FORECAST AREA LATER
TODAY/TONIGHT BUT OVERALL...THE PREVIOUSLY MENTIONED VORT LOBES WILL
LARGELY MISS OUR FORECAST AREA FOR THE DURATION OF THE EVENT...PER
LATEST MODELS. HOWEVER...DYNAMICAL FORCING WILL CONTINUE TO AFFECT
SOUTHEAST ARIZONA AND ADVECTION OF THOSE SHOWERS INTO OUR AREA MAY
OCCUR SATURDAY MORNING. AS FOR THUNDERSTORM POTENTIAL...MODEL CAPE
FOR THIS AFTERNOON CONTINUES TO LOOK QUITE MEAGER FROM THE GFS AND
BETTER FROM THE NAM. RAP IS EVEN BETTER THAN THE NAM BUT STILL UNDER
200 J/KG. HRRR SHOWS SOME ISOLATED WEAK CONVECTION AS WELL. THUS
WILL HOLD ON THE SLIGHT CHANCES. NAM SHOWS A NOTABLE INCREASE IN
CAPE FOR SATURDAY WHILE THE GFS IS STILL MEAGER. AS FOR CHANGES TO
THE FORECAST IN THE SHORT TERM...MAY NEED TO MAKE SOME DOWNWARD
ADJUSTMENTS TO POPS...MORE NOTICEABLY IN OUR WESTERN AREAS. MORE
LATER.
&&
.PREVIOUS DISCUSSION ISSUED 255 AM MST/155 AM PST...
AT 2 AM...VIGOROUS UPPER LEVEL LOW CONTINUED TO SPIN JUST OFF THE
NRN BAJA COAST...SPREADING COPIOUS AMOUNTS OF MOISTURE NORTHWARD
INTO ARIZONA AND PORTIONS OF FAR SERN CA. CURRENT BLENDED TOTAL
PRECIP WATER IMAGERY SHOWED 1.25-1.5 INCHES OF PWAT MOVING NORTH
ACROSS CENTRAL BAJA...POISED TO MOVE NORTH INTO ARIZONA DURING THE
DAY TODAY. IR IMAGERY AT 2 AM SHOWED AN IMPRESSIVE STREAM OF CLOUDS
OVERSPREADING THE AREA FROM THE SOUTH...AND THE LATEST 1.3 DEG RADAR
LOOP SHOWED WIDESPREAD SHOWERS SPREADING NORTH ACROSS MUCH OF
CENTRAL/SOUTH CENTRAL AZ WITH AREAL COVERAGE VIRTUALLY 100 PERCENT.
OVER THE PAST 6 HOURS...VIRTUALLY EVERY MARICOPA COUNTY FLOOD
CONTROL DISTRICT GAGE HAS PICKED UP MEASURABLE RAIN...WITH MOST
TOTALS BETWEEN ONE TENTH AND ONE THIRD OF AN INCH. PHOENIX HAS
PICKED UP 0.36 INCHES SO FAR WITH THIS EVENT...AND THE PERIODS OF
EXPECTED HEAVIEST RAINFALL HAVE YET TO OCCUR.
MODEL GUIDANCE HAS BEEN REMARKABLY CONSISTENT OVER THE PAST FEW DAYS
REGARDING THE EVOLUTION OF THIS WET WEATHER SYSTEM...INCLUDING
DETAILS SUCH AS TIMING AND QPF AMOUNTS. ALL GUIDANCE CALLS FOR AN
UPPER CLOSED LOW TO FORM OVER FAR SERN CA BY LATER THIS AFTERNOON...
AND AS THE LOW SPINS UP THE MOST SIGNIFICANT PRECIP IS EXPECTED TO
OCCUR OVER THE AREA...ESPECIALLY ACROSS SOUTH CENTRAL AZ. POPS WILL
STAY VERY HIGH TODAY...LIKELY OUT WEST AND CATEGORICAL OVER OUR
EASTERN FORECAST ZONES...WITH BASICALLY A 100 PERCENT CHANCE OF RAIN
CONTINUING FOR THE GREATER PHOENIX AREA. QPF AMOUNTS SHOULD RANGE
BETWEEN ONE QUARTER AND ONE HALF INCH TODAY ACROSS SOUTH CENTRAL
AZ...WITH LOCALLY HIGHER AMOUNTS OVER HIGHER TERRAIN AREAS TO THE
NORTH AND EAST OF PHOENIX. THERE WILL BE MODEST INSTABILITY OVER THE
CENTRAL DESERTS TODAY SO WE WILL CONTINUE TO CALL FOR A SLIGHT
CHANCE OF AFTN/EVE THUNDERSTORMS BASICALLY FROM THE LOWER CO RIVER
VALLEY EASTWARD. SHOULD A STORM DEVELOP...RAINFALL TOTALS WILL
BECOME ENHANCED. GIVEN ALL OF THE CLOUDS AND SHOWERS...HIGH TEMPS
TODAY WILL STAY WELL BELOW SEASONAL NORMALS WITH HIGHS OVER SOUTH
CENTRAL AZ TO HOVER IN THE UPPER 50S TO LOW 60S.
FOR TONIGHT THROUGH THE EVENING ON SATURDAY...THE UPPER LOW IS
PROGGED TO VERY SLOWLY TRANSLATE TO THE EAST/SOUTHEAST AND AS IT
DOES SO THERE WILL BE PERIODS OF ENHANCED LIFT/UVV AS VORT
SPOKES/LOBES ROTATE AROUND THE MAIN UPPER LOW. WITH MOISTURE OVER
THE LOWER DESERTS EXPECTED TO REMAIN VERY HIGH THROUGH SATURDAY...
PWAT VALUES REMAINING BETWEEN 0.75 AND 1.00 INCH...THE CONTINUED
DYNAMICS FROM THE VORT LOBES WILL KEEP SHOWERS GOING OVER MOST THE
REGION AND POPS WILL STAY ELEVATED. CHANCE TO LIKELY POPS WILL
REMAIN ACROSS SOUTH CENTRAL AZ TONIGHT AND SATURDAY...WITH POPS
DROPPING INTO THE SLIGHT CHANCE CATEGORY OVER SERN CA DURING THE DAY
ON SATURDAY.
OVERALL...WE ARE LOOKING AT STORM TOTAL AMOUNTS ENDING SATURDAY
EVENING RANGING FROM ONE QUARTER TO ONE HALF INCH OVER THE WESTERN
DESERTS...TO OVER ONE INCH ACROSS THE CENTRAL DESERTS INCLUDING THE
GREATER PHOENIX AREA. HIGHER AMOUNTS...1.25 TO NEARLY 2 INCHES...ARE
POSSIBLE IN THE HIGHER TERRAIN AREAS NORTH AND EAST OF PHOENIX. FOR
NOW WE EXPECT RAIN TO BE CONTINUAL AND NOT LOCALLY HEAVY OR INTENSE
ENOUGH TO WARRANT FLASH FLOODING CONCERNS. THERE MAY BE AREAS THAT
EXPERIENCE SOME URBAN OR SMALL STREAM FLOODING AS TIME WEARS ON AND
WE CAN SIMPLY ISSUE FLOOD ADVISORY PRODUCTS AS NEEDED TO COVER THIS
CONTINGENCY.
HIGH TEMPS SATURDAY WILL REMAIN WELL BELOW NORMAL AND WILL CHANGE
LITTLE FROM TODAYS EXPECTED READINGS. HIGHS SATURDAY IN THE GREATER
PHOENIX AREA WILL STAY IN THE UPPER 50S TO LOW 60S...NEARLY 10
DEGREES BELOW SEASONAL NORMALS.
SUNDAY THROUGH THURSDAY...
SUNDAY LOOKS TO BE A DRY AND WARMER DAY. PATCHY MORNING FOG IS A
POSSIBILITY BUT THERE MAY BE ENOUGH LINGERING CLOUDS TO HINDER THE
RADIATIONAL COOLING NECESSARY. THE RIDGE SLOWLY BUILDS INTO THE
WEST MONDAY THROUGH THURSDAY FOR A GRADUAL WARMING TREND...AND WE
CAN EXPECT DESERT HIGHS TO REACH BACK INTO THE LOW TO MID 70S BY
NEXT WEDNESDAY...WITH THE WARMER WESTERN DESERTS RISING TO NEAR 80
BY NEXT THURSDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...PERIODS OF
RAIN WILL CONTINUE ACROSS SOUTH-CENTRAL ARIZONA INTO SATURDAY.
CEILINGS ARE EXPECTED TO BE GENERALLY AOB 6KFT THE ENTIRE PERIOD AND
PERIODICALLY LOWER BLO 2KFT...AS SOME OF THE HEAVIER SHOWERS MOVE
ACROSS THE REGION. REDUCTIONS IN VSBY DOWN TO NEAR 1SM WERE SEEN
EARLY THIS MORNING. PREVAILING VSBY THE REMAINDER OF TODAY IS
EXPECTED TO BE GENERALLY AT OR ABOVE 6SM...THOUGH SOME OF THE
HEAVIER RAIN MAY CAUSE RESTRICTIONS LESS THAN 3SM. THERE IS A SLIGHT
CHANCE OF AFTERNOON THUNDERSTORMS TODAY...THOUGH CONFIDENCE IS NOT
GREAT ENOUGH TO WARRANT INSERTION IN TAFS. WINDS WILL REMAIN
LIGHT...BUT COULD BECOME GUSTY...SHOULD THUNDERSTORMS DEVELOP IN THE
AREA OF TAF STATIONS.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
LIGHT RAIN IS EXPECTED THROUGH ABOUT MID DAY ACROSS SOUTHEAST
CALIFORNIA. AREAS THAT SEE HEAVIER RAINFALL COULD SEE SOME PATCHY
FOG DEVELOP ONCE RAIN HAS ENDED. CEILINGS WILL RANGE FROM 3500 TO
5KFT FOR MOST OF THE FORECAST PERIOD. WINDS WILL BE GENERALLY LESS
THAN 10 KTS AND WILL FAVOR A WEST TO NORTHWEST DIRECTION.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
DRIER AND SIGNIFICANTLY WARMER WEATHER IS EXPECTED...AS HIGH
PRESSURE BEGINS BUILDING BACK INTO THE REGION. HIGH TEMPERATURES IN
THE LOWER DESERTS WILL START OUT IN THE UPPER 60S ON SUNDAY AND
GRADUALLY CLIMB INTO THE UPPER 70S BY THURSDAY. WINDS ARE EXPECTED
TO BE LIGHT AND VARIABLE FOR MOST OF THE FORECAST PERIOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...CB
AVIATION...MCLANE
FIRE WEATHER...MCLANE
AREA FORECAST DISCUSSION
NWS TUCSON AZ
945 AM MST FRI JAN 30 2015
.SYNOPSIS...A STORM SYSTEM WILL BRING VALLEY RAIN AND MOUNTAIN SNOW
INTO SATURDAY. MINOR FLOODING WILL OCCUR DUE TO PERIODS OF HEAVY
RAINFALL. THE MOST SIGNIFICANT SNOWFALL WILL BE ABOVE 8000 FEET...OR
ACROSS THE HIGHEST PEAKS. EXPECT MUCH COOLER DAYTIME TEMPERATURES
INTO THIS WEEKEND. DRY CONDITIONS WITH A WARMING TREND WILL THEN
OCCUR EARLY NEXT WEEK.
&&
.DISCUSSION...KEMX WSR-88D DETECTED A BAND OF 30-55 DBZ ECHOES JUST
EAST OF THE TUCSON METRO AREA...OR MOSTLY ACROSS WESTERN/CENTRAL
COCHISE COUNTY EXTENDING NWD INTO SRN GRAHAM COUNTY. OTHER MUCH
WEAKER ECHOES WERE WEST OF TUCSON...OR ACROSS THE TOHONO O`ODHAM
NATION AND SRN PINAL COUNTY. MOVEMENT OF THESE ECHOES WAS TO THE NE
AT 20-30 MPH.
THERE HAVE BEEN SOME IMPRESSIVE RAINFALL AMOUNTS THUS FAR...
ESPECIALLY ACROSS THE HIGHER TERRAIN. NEARLY 4.25 INCHES HAS BEEN
OBSERVED AT PARK TANK...OR ON THE NRN PORTION OF THE RINCON MTNS.
ALSO...MOUNT LEMMON HAS MEASURED 3.58 INCHES...AND NRN GREENLEE
COUNTY NORTH OF CLIFTON HAD RECEIVED 2.64 INCHES. FINALLY...ABOUT 2
INCHES OF RAIN HAS FALLEN ACROSS THE DRAGOON MOUNTAINS AND HUACHUCA
MOUNTAINS IN WRN COCHISE COUNTY.
30/12Z KTWC SOUNDING TOTAL PRECIP WATER VALUE OF 1.18 INCHES IS THE
HIGHEST PRECIP WATER VALUE ON RECORD FOR JANUARY...BREAKING THE
PREVIOUS RECORD OF 1.12 INCHES SET ON JANUARY 9, 2009.
UPPER LEVEL TROUGH OVER THE GREAT BASIN/SWRN CONUS WITH 563 DM LOW
CENTERED NEAR SAN DIEGO WILL REMAIN QUASI-STATIONARY INTO SAT. FOR
THE REMAINDER OF TODAY...SEVERAL RUC HRRR SOLUTIONS AS WELL AS RADAR
TRENDS SUGGEST THAT THE MOST SIGNIFICANT RAINFALL WILL OCCUR ACROSS
COCHISE/GREENLEE/GRAHAM COUNTIES EAST OF TUCSON. HOWEVER...THE RUC
HRRR AS WELL AS THE UNIV OF AZ WRF-NAM AND WRF-GFS SOLUTIONS
INDICATE THAT ADDITIONAL SHOWERS WILL DEVELOP DURING THE NEXT
SEVERAL HOURS WEST TO SOUTHWEST OF TUCSON. THIS ACTIVITY THEN HOLDS
THE POTENTIAL TO PRODUCE THUNDERSTORMS GIVEN SUFFICIENT INSTABILITY.
SNOW LEVELS WILL REMAIN QUITE HIGH TODAY...ESSENTIALLY ABOVE 8000
FEET.
ONLY VERY MINOR ADJUSTMENTS WILL BE MADE TO THE INHERITED OFFICIAL
FORECAST. WIDESPREAD VALLEY RAIN WILL OCCUR INTO SAT...WITH
SIGNIFICANT SNOW ACCUMULATIONS LIMITED TO LOCALES ABOVE 8000 FEET.
THE AWIPS PRODUCT PHXWSWTWC /WMO HEADER WWUS45 KTWC/ CONTAINS MORE
INFORMATION. PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER
DETAIL.
&&
.AVIATION...VALID THRU 31/18Z.
WIDESPREAD VALLEY RAIN AND MOUNTAIN SNOW WILL OCCUR INTO SATURDAY
MORNING AS LOW PRESSURE SYSTEM MOVES OVER THE AREA. THERE IS A
SLIGHT CHANCE OF THUNDERSTORMS ACROSS MUCH OF THE AREA THIS
AFTERNOON. CLOUD DECKS OUTSIDE OF PRECIPITATION WILL GENERALLY BE
4-8K FT AGL. HOWEVER...WIDESPREAD MVFR CONDITIONS AND LOCAL IFR
CONDITIONS MAINLY FROM LOW CEILINGS WILL OCCUR DUE TO SHOWERS.
SURFACE WIND INTO SATURDAY MORNING WILL GENERALLY BE ELY/SELY AT
5-15 KTS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...EXPECT WIDESPREAD VALLEY RAIN AND MOUNTAIN SNOW
TODAY THROUGH SATURDAY WITH A STRAY LIGHTNING STRIKE OR TWO NOT OUT
OF THE QUESTION. THE MOST SIGNIFICANT SNOWFALL WILL OCCUR ACROSS THE
HIGHEST PEAKS OF THE WHITE MOUNTAINS...MOUNT GRAHAM...AND THE
CATALINA AND RINCON MOUNTAINS NEAR TUCSON. A FEW LINGERING SHOWERS
WILL OCCUR MAINLY EAST TO SOUTH OF TUCSON SUNDAY WITH DRY CONDITIONS
EXPECTED AREA-WIDE EARLY NEXT WEEK. 20-FOOT WINDS INTO SATURDAY
MORNING WILL GENERALLY BE FROM THE EAST TO SOUTHEAST AT 5-15 MPH.
EXPECT DIURNAL WIND TRENDS TO RESUME THIS WEEKEND THROUGH EARLY NEXT
WEEK.
&&
.PREV DISCUSSION...SURFACE HIGH OVER THE GREAT PLAINS HAS SETTLED IN
A LITTLE FURTHER EAST THAN PREVIOUSLY PROGGED...WHICH HAS LIMITED
THE TIGHTENING OF THE PRESSURE GRADIENT OUT EAST. THAT BEING SAID...
OVER THE LAST SEVERAL HOURS THE AREA HAS SEEN SOME TIGHTENING OF THE
GRADIENT AND IT/S RESULTANT WIND INCREASE. THESE WINDS SHOULD STAY
PRESENT THROUGH THE AFTERNOON WHEN THE GRADIENT RELAXES.
UPPER TROUGH/LOW CENTERED NEAR SOUTHERN CALIFORNIA THIS MORNING
WILL CONTINUE TO DEEPEN AS IT MOVES ONSHORE TODAY. THIS WILL KEEP
A STEADY STREAM OF MOISTURE MOVING INTO THE AREA TODAY AND
TOMORROW. TOMORROW AFTERNOON THE LOW WILL BEGIN TO SLIDE SOUTHEAST
WHICH WILL SHUT THIS MOISTURE TAP OFF...THOUGH THERE WILL BE
ENOUGH REMNANT MOISTURE IN PLACE FOR CONTINUAL SHOWERS ACROSS THE
AREA THROUGH THE EVENING HOURS. THEN THE AREA SHOULD SEE SOME
DISSIPATION FROM NORTHWEST TO SOUTHEAST/EAST THROUGH SUNDAY EARLY
EVENING.
FOR THIS MORNING GUIDANCE HAS SHOWN A LITTLE MORE WARM AIR ADVECTION
THAN PREVIOUSLY PROGGED...WHICH THE 00Z SOUNDING SUPPORTS.
THEREFORE...HAVE UPPED SNOW LEVELS SOME THOUGH THIS REALLY DIDN/T
IMPACT THE SNOW ACCUMULATIONS THAT MUCH. IT STILL LOOKS LIKE SNOW
LEVELS WILL BEGIN TO LOWER TO ABOUT 8500 FEET THIS AFTERNOON...8000
FEET BY THIS EVENING...AND 7000 FEET BY SATURDAY MORNING.
THOUGH THIS STORM WILL CONTINUALLY BRING WIDESPREAD RAIN/SNOW TO THE
AREA...ONE CONCERN IS THE DRY SLOT PROGGED FOR THIS MORNING AND
EARLY AFTERNOON ACROSS THE CENTRAL ZONES. THIS COULD IMPACT QPF
VALUES THOUGH DIDN/T HAVE THE CONFIDENCE TO LOWER THEM TOO MUCH AS
INSTABILITY INCREASES DURING THIS TIME FRAME AS WELL. LATEST HRRR
SOLUTION DOES SHOW A LULL IN SHOWER ACTIVITY OUT WEST DURING THIS
TIME...THOUGH THIS IS MAINLY IN COVERAGE. THE IMPACT OF THE DRY SLOT
WILL LESSEN THROUGHOUT THE DAY AND ESPECIALLY DURING THE OVERNIGHT AS
THE LOW WOBBLES SOUTHEAST SOME. THIS WILL ALSO DECREASE THE
EFFICIENCY OF THESE SHOWERS DURING THE DAY SATURDAY.
GENERALLY SPEAKING HAVE CONTINUED THE QPF/SNOW TOTALS ADVERTISED
THE LAST COUPLE OF DAYS...AS WELL AS TIMING. THE ONE EXCEPTION IS
AN INCREASE OVER MT GRAHAM TO ACCOUNT FOR TODAY/S EXPECTED
CONVECTIVE ENHANCEMENT.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL NOON MST SATURDAY FOR AZZ510-511
ABOVE 7000 FEET.
WINTER STORM WARNING FROM 11 AM THIS MORNING TO NOON MST
SATURDAY FOR AZZ514 ABOVE 7000 FEET.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...FRANCIS
PREVIOUS DISCUSSION...MEADOWS
AVIATION/FIRE WEATHER...FRENCH
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
155 PM PST FRI JAN 30 2015
.SYNOPSIS...
LOW PRESSURE TO THE SOUTHEAST WILL BRING ISOLATED SHOWERS TO PARTS
OF THE AREA THROUGH TONIGHT. OFFSHORE FLOW WILL DEVELOP THIS
WEEKEND...RESULTING IN A CLEARING AND WARMING TREND. HIGH PRESSURE
WILL BRING ABOVE NORMAL TEMPERATURES AND FAIR SKIES NEXT WEEK. A
COLD FRONT MAY APPROACH THE CENTRAL COAST BY THE END OF NEXT WEEK.
&&
.SHORT TERM (TODAY-MON)...
SATELLITE IMAGERY SHOWS THE UPPER-LEVEL LOW CENTERED OVER SE CA THIS
AFTERNOON. RADAR SHOWING AN INCREASE IN CONVECTIVE SHOWER ACTIVITY
LIKE THE HRRR WAS SUGGESTING EARLIER...SO SLIGHT CHANCE OF SHOWERS
WILL CONTINUE THROUGH THIS AFTERNOON FOR MUCH OF LA COUNTY AND PARTS
OF VENTURA COUNTY. THE BEST CHANCE OF MEASURABLE PRECIP WILL BE IN
THE MOUNTAINS...BUT AMOUNTS SHOULD CONTINUE TO BE VERY LIGHT.
SHOWERS WILL QUICKLY COME TO AN END THIS EVENING AS THE UPPER-LOW
CONTINUES TO DRIFT SE...WITH SLIGHT CHANCES LINGERING OVER THE SAN
GABRIELS THROUGH LATE TONIGHT.
PATCHY DENSE FOG WILL BE POSSIBLE IN THE SALINAS VALLEY AGAIN
TONIGHT. SOME PATCHY LOW CLOUDS AND FOG MAY ALSO DEVELOP ON THE LA
COAST TOWARDS DAYBREAK AS A WEAK EDDY SPINS UP.
NE WINDS WILL INCREASE ACROSS THE MOUNTAINS TOMORROW MORNING AS THE
UPPER LOW CONTINUES TO DRIFT SE AND A RIDGE BUILDS INTO NORTHERN
CA...SETTING UPPER NE FLOW ALOFT. LOOKS LIKE THE NE WINDS WILL PEAK
TOMORROW AFTERNOON AND EVENING. NOT PLANNING ON PUTTING ANY WIND
ADVISORIES OUT AT THIS TIME...BUT THE EVENING SHIFT WILL HAVE TO
TAKE A CLOSER LOOK AT THE 00Z MODEL RUNS. RIGHT NOW JUST EXPECTING
SOME ISOLATED NE GUSTS TO 45 MPH IN THE LA MOUNTAINS TOMORROW
AFTERNOON AND EVENING. OFFSHORE WINDS WILL CONTINUE THROUGH SUNDAY
MORNING...BUT WILL WEAKEN AS THE UPPER-LEVEL RIDGE MOVES OVERHEAD.
SLIGHT WARMING IS EXPECTED TOMORROW WITH FEWER CLOUDS AND AN
INCREASE IN OFFSHORE FLOW...WITH FURTHER WARMING ON SUNDAY AS THE
RIDGE MOVES OVERHEAD AND WEAK OFFSHORE FLOW CONTINUES. HIGHS ON
SUNDAY WILL GENERALLY RANGE FROM THE LOW 70S TO THE UPPER 70S FOR
THE COASTAL AND VALLEY AREAS. SLIGHT COOLING POSSIBLE ON MONDAY AS
THE RIDGE WEAKENS A LITTLE...BUT OVERALL VERY LITTLE CHANGE.
.LONG TERM (TUE-FRI)...
NOT MUCH WEATHER TO TALK ABOUT IN THE LONG RANGE. VERY LITTLE CHANGE
IN TEMPERATURES EXPECTED AS A RIDGE REMAINS IN PLACE. THE RIDGE
BUILDS A BIT ON WEDNESDAY AND THURSDAY WITH A TROUGH APPROACHING
FROM THE WEST. MODELS AGREE THAT A COLD FRONT WILL TRY TO TAKE A RUN
AT THE CENTRAL COAST LATE IN THE WEEK...BEFORE A RIDGE DEVELOPS
AGAIN FOR NEXT WEEKEND. A SLIGHT CHANCE OF RAIN MAY NEED TO BE ADDED
TO THE CENTRAL COAST FOR FRIDAY IF THE LATEST ECMWF IS RIGHT. FOR
NOW KEPT CHANCES OF RAIN BELOW 20 PERCENT.
&&
.AVIATION...30/1800Z...
MID/UPPER LEVEL TROUGH OF LOW PRESSURE CENTERED EAST OF THE AREA
WILL SHIFT EAST AND SOUTH. UPPER LEVEL LIGHT TO MODERATE NORTHWEST
WINDS WILL BECOME MODERATE NORTH BY 31/07Z WHILE MID LEVEL LIGHT TO
MODERATE NORTH WINDS BECOME MODERATE NORTHEAST AFTER 31/20Z.
MID/UPPER LEVEL MOISTURE IS EXPECTED TO DECREASE AFTER 31/06Z.
FREEZING LEVEL WAS AROUND 8KFT THIS MORNING AND WILL DIFFER LITTLE
SATURDAY MORNING. MIXED WEAK ONSHORE AND OFFSHORE WINDS THROUGH
31/08Z AND AFTER 31/19Z OTHERWISE WEAK OFFSHORE GRADIENT. NO MARINE
INVERSION THIS MORNING AND A WEAK INVERSION IS EXPECTED WITH CLOUD
TOPS NEAR 2KFT SATURDAY MORNING.
MARINE LAYER AT LAX AT 1725Z IS NONE.
KLAX...CURRENT SKY/VSBY CONDITIONS WILL LIKELY PERSIST THROUGH
31/03Z AND THERE IS A CHANCE OF LIGHT SHOWERS THROUGH 30/21Z. THERE
IS A CHANCE CIGS 015 BETWEEN 31/13-31/19Z.
KBUR...CURRENT SKY/VSBY CONDITIONS WILL LIKELY PERSIST THROUGH
31/08Z AND THERE IS A CHANCE OF LIGHT SHOWERS THROUGH 30/22Z.
VIRTUALLY CERTAIN - 95-100%
VERY LIKELY - 80-95%
LIKELY - 60-80%
CHANCE - 30-60%
VERY UNLIKELY - 20% OR LESS
&&
.MARINE...30/200 PM...
SMALL CRAFT ADVISORY CONDITIONS FOR NORTHWEST WIND AND SEAS AROUND
10 FEET FROM PIEDRAS BLANCAS TO POINT SAL FROM 10-60 NM AND FROM THE
OUTER WATERS FROM POINT SAL TO SAN CLEMENTE ISLAND WILL LIKELY
PERSIST THROUGH SATURDAY MORNING. OTHERWISE A BROAD AREA OF LOW
PRESSURE WILL CONTINUE TO DEEPEN WHILE REMAINING NEARLY STATIONARY
OVER THE CENTRAL PACIFIC THROUGH SATURDAY EVENING AND THEN PERSIST
THROUGH SUNDAY. GALE FORCE WINDS WITHIN A FETCH AREA ORIENTED
BETWEEN 290-300 DEGREES RELATIVE TO VENTURA COUNTY IS EXPECTED TO
GENERATE SEAS AROUND 20 FEET. AND THE SWELLS FROM THE FETCH AREA ARE
EXPECTED TO ARRIVE NEXT WEEK TUESDAY AND REMAIN BELOW SCA FOR
HAZARDOUS SEAS.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...SUKUP
AVIATION/MARINE...30
SYNOPSIS...SETO
WWW.WEATHER.GOV/LOSANGELES
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
1013 AM PST FRI JAN 30 2015
.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL BRING MOIST NORTHEAST FLOW INTO THE
SOUTHERN PORTION OF THE FORECAST AREA...WITH LIGHT RAIN SHOWERS
POSSIBLE. WEAK OFFSHORE WINDS WILL INCREASE BY SATURDAY NIGHT
THROUGH SUNDAY MORNING. HIGH PRESSURE WILL BRING WARMER TEMPERATURES
AND MOSTLY CLEAR SKIES OVER THE WEEKEND AND INTO NEXT WEEK.
&&
.SHORT TERM (TODAY-SUN)...
FORECAST THIS MORNING WAS IN PRETTY GOOD SHAPE. NO MAJOR CHANGES
MADE. JUST KEPT THE SLIGHT CHANCE OF SHOWERS GOING THIS AFTERNOON
FOR EASTERN PARTS OF VENTURA COUNTY. LATEST RADAR IMAGERY SHOWS A
DRYING TREND. THE HRRR DOES AS WELL...BUT IT ALSO SHOWS A LITTLE
FLARE UP OF SHOWER ACTIVITY THIS AFTERNOON...SO EASTERN VENTURA
COUNTY AND MUCH OF LA COUNTY COULD CONTINUE TO SEE ISOLATED TO
SCATTERED SHOWERS THIS AFTERNOON. RAINFALL AMOUNTS IN VENTURA AND LA
COUNTY HAVE BEEN LIGHT (GENERALLY LESS THAN 0.05"...EXCEPT SOME
0.25" AMOUNTS IN THE SAN GABRIELS). WITH WEAK OFFSHORE FLOW AND
PLENTY OF DRY AIR AT THE LOW LEVELS...ANY ADDITIONAL PRECIP WILL
CONTINUE TO BE VERY LIGHT. OVERALL TREND FOR THE NEXT 24-30 HOURS
WILL BE A DECREASE IN SHOWER ACTIVITY AS THE UPPER LOW DRIFTS TO THE
SOUTHEAST.
***FROM PREVIOUS DISCUSSION***
SCATTERED LIGHT SHOWERS HAVE BEEN OCCURRING ACROSS L.A. COUNTY SINCE
LAST NIGHT INTO EARLY THIS MORNING. HOWEVER...RAINFALL AMOUNTS HAVE
BEEN ANEMIC. WELL BELOW A TENTH OF AN INCH EVERYWHERE. THE UPPER LOW
WHICH IS CURRENTLY OFF THE SAN DIEGO COAST WILL BECOME MORE
ELONGATED AND STRETCH MORE NORTH TO SOUTH. THIS WILL ALLOW FOR MORE
CLOUD COVERAGE OVER MOST OF THE FORECAST AREA...ESPECIALLY THE
EASTERN HALF....WITH THE NORTHWESTERN PORTION LIKELY UNDER MOSTLY
SUNNY OR PARTLY CLOUDY SKIES TODAY.
SNOW LEVELS WILL REMAIN OVER 7000 FT TODAY...BUT SHOULD LOWER TO
6500 FT EARLY THIS EVENING. NOT EXPECTING MUCH OF ANY SNOWFALL WITH
THIS SYSTEM...BUT A FEW INCHES ABOVE 7000 FT IN THE EASTERN SAN
GABRIEL MOUNTAINS WILL BE POSSIBLE THROUGH SATURDAY MORNING.
HIGH TEMPS WILL BE A FEW DEGREES COOLER ACROSS THE BOARD
TODAY...ESPECIALLY OVER LA/VTU COUNTIES WITH MOSTLY CLOUDY SKIES. BY
TONIGHT MOST OF THE PRECIP WILL BE EAST AND SOUTH OF THE FORECAST
AREA. THERE WILL CONTINUE TO BE SOME LINGERING LOW LEVEL CLOUDS OVER
THE MOUNTAINS AND ANTELOPE VALLEY THROUGH EARLY SATURDAY
AFTERNOON...BUT SKIES SHOULD BEGIN TO CLEAR ACROSS COAST AND VALLEYS
BY LATE SAT MORNING. THERE WILL BE SOME INCREASING OFFSHORE WINDS
ACROSS LA/VTU MTNS AND WIND PRONE LA/VTU COUNTY PASSES AND CANYONS
AND ACROSS THE OXNARD PLAIN SATURDAY MORNING THROUGH MID AFTERNOON
HOURS. WINDS SHOULD REMAIN BELOW WIND ADVISORY THRESHOLDS. BUT WILL
BE CLOSE FOR THE MOUNTAINS AS THERE WILL BE A LIMITED WINDOW OF
UPPER LEVEL SUPPORT. NOT EXPECTING MUCH OF A WARM UP ON SATURDAY BUT
MAYBE A DEGREE OR TWO ALONG THE COAST AND COASTAL VALLEY AREAS DUE
TO OFFSHORE FLOW...ESPECIALLY THE CENTRAL COAST WITH EASTERLY FLOW
EXPECTED. BY SUNDAY THE UPPER LOW DROPS DOWN OVER BAJA WHILE A RIDGE
BUILDS IN FROM THE WEST. EXPECT BETTER WARMING ON SUNDAY ACROSS
COAST AND COASTAL VALLEYS INTO THE MID 70S WITH MOSTLY SUNNY SKIES.
NOT ANTICIPATING ANY MARINE LAYER STRATUS ISSUES...EXCEPT FOR LA
COUNTY COAST SATURDAY MORNING.
.LONG TERM (MON-THU)...ONCE THE UPPER LOW MOVES OUT OF THE REGION
STRONG UPPER LVL RIDGE WILL BUILD IN FROM THE SOUTHWEST OF
CALIFORNIA FOR MOST OF THE WEEK. THERE COULD BE A FEW HIGH CLOUDS
AROUND A DIRTY RIDGE TO AFFECT THE NORTHERN PORTION OF THE FORECAST
AREA...MAINLY N OF POINT CONCEPTION. NOT EXPECTING MUCH IN THE WAY
OF WINDS AS SURFACE PRESSURE GRADIENTS LOOK TO REMAIN PRETTY
NEUTRAL. THAT BEING SAID...THIS WILL ALLOW FOR SOME ADDITIONAL
WARMING UNDER THE DOME OF HIGH PRESSURE WITH HIGHS REACHING THE MID
TO UPPER 70S AND POSSIBLY AROUND 80 BY WED/THU. HAVE ADDED SOME
PATCHY LOW CLOUDS FOR THE CENTRAL COAST THU NIGHT INTO FRI MORNING
AS THE UPPER RIDGE WILL BEGIN TO FLATTEN SOME AND ONSHORE FLOW
SHOULD INCREASE. AT THIS POINT...IT LOOKS LIKE A SERIES OF STORMS
WILL AFFECT THE NORTHERN PORTION OF THE STATE BY LATE NEXT WEEK.
&&
.AVIATION...30/1800Z...
MID/UPPER LEVEL TROUGH OF LOW PRESSURE CENTERED EAST OF THE AREA
WILL SHIFT EAST AND SOUTH. UPPER LEVEL LIGHT TO MODERATE NORTHWEST
WINDS WILL BECOME MODERATE NORTH BY 31/07Z WHILE MID LEVEL LIGHT TO
MODERATE NORTH WINDS BECOME MODERATE NORTHEAST AFTER 31/20Z.
MID/UPPER LEVEL MOISTURE IS EXPECTED TO DECREASE AFTER 31/06Z.
FREEZING LEVEL WAS AROUND 8KFT THIS MORNING AND WILL DIFFER LITTLE
SATURDAY MORNING. MIXED WEAK ONSHORE AND OFFSHORE WINDS THROUGH
31/08Z AND AFTER 31/19Z OTHERWISE WEAK OFFSHORE GRADIENT. NO MARINE
INVERSION THIS MORNING AND A WEAK INVERSION IS EXPECTED WITH CLOUD
TOPS NEAR 2KFT SATURDAY MORNING.
MARINE LAYER AT LAX AT 1725Z IS NONE.
KLAX...CURRENT SKY/VSBY CONDITIONS WILL LIKELY PERSIST THROUGH
31/03Z AND THERE IS A CHANCE OF LIGHT SHOWERS THROUGH 30/21Z. THERE
IS A CHANCE CIGS 015 BETWEEN 31/13-31/19Z.
KBUR...CURRENT SKY/VSBY CONDITIONS WILL LIKELY PERSIST THROUGH
31/08Z AND THERE IS A CHANCE OF LIGHT SHOWERS THROUGH 30/22Z.
VIRTUALLY CERTAIN - 95-100%
VERY LIKELY - 80-95%
LIKELY - 60-80%
CHANCE - 30-60%
VERY UNLIKELY - 20% OR LESS
&&
.MARINE...30/900 AM...
SMALL CRAFT ADVISORY CONDITIONS FOR NORTHWEST WIND AND SEAS AROUND
10 FEET FROM PIEDRAS BLANCAS TO POINT SAL FROM 10-60 NM AND FROM THE
OUTER WATERS FROM POINT SAL TO SAN CLEMENTE ISLAND WILL LIKELY
PERSIST THROUGH SATURDAY MORNING. OTHERWISE A BROAD AREA OF LOW
PRESSURE WILL CONTINUE TO DEEPEN WHILE REMAINING NEARLY STATIONARY
OVER THE CENTRAL PACIFIC THROUGH SATURDAY EVENING AND THEN PERSIST
THROUGH SUNDAY. GALE FORCE WINDS WITHIN A FETCH AREA ORIENTED
BETWEEN 290-300 DEGREES RELATIVE TO VENTURA COUNTY IS EXPECTED TO
GENERATE SEAS AROUND 20 FEET. AND THE SWELLS FROM THE FETCH AREA ARE
EXPECTED TO ARRIVE NEXT WEEK TUESDAY AND REMAIN BELOW SCA FOR
HAZARDOUS SEAS.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...KAPLAN/SUKUP
AVIATION/MARINE...30
WWW.WEATHER.GOV/LOSANGELES
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
954 AM PST FRI JAN 30 2015
.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL BRING MOIST NORTHEAST FLOW INTO THE
SOUTHERN PORTION OF THE FORECAST AREA...WITH LIGHT RAIN SHOWERS
POSSIBLE. WEAK OFFSHORE WINDS WILL INCREASE BY SATURDAY NIGHT
THROUGH SUNDAY MORNING. HIGH PRESSURE WILL BRING WARMER TEMPERATURES
AND MOSTLY CLEAR SKIES OVER THE WEEKEND AND INTO NEXT WEEK.
&&
.SHORT TERM (TODAY-SUN)...
FORECAST THIS MORNING WAS IN PRETTY GOOD SHAPE. NO MAJOR CHANGES
MADE. JUST KEPT THE SLIGHT CHANCE OF SHOWERS GOING THIS AFTERNOON
FOR EASTERN PARTS OF VENTURA COUNTY. LATEST RADAR IMAGERY SHOWS A
DRYING TREND. THE HRRR DOES AS WELL...BUT IT ALSO SHOWS A LITTLE
FLARE UP OF SHOWER ACTIVITY THIS AFTERNOON...SO EASTERN VENTURA
COUNTY AND MUCH OF LA COUNTY COULD CONTINUE TO SEE ISOLATED TO
SCATTERED SHOWERS THIS AFTERNOON. RAINFALL AMOUNTS IN VENTURA AND LA
COUNTY HAVE BEEN LIGHT (GENERALLY LESS THAN 0.05"...EXCEPT SOME
0.25" AMOUNTS IN THE SAN GABRIELS). WITH WEAK OFFSHORE FLOW AND
PLENTY OF DRY AIR AT THE LOW LEVELS...ANY ADDITIONAL PRECIP WILL
CONTINUE TO BE VERY LIGHT. OVERALL TREND FOR THE NEXT 24-30 HOURS
WILL BE A DECREASE IN SHOWER ACTIVITY AS THE UPPER LOW DRIFTS TO THE
SOUTHEAST.
***FROM PREVIOUS DISCUSSION***
SCATTERED LIGHT SHOWERS HAVE BEEN OCCURRING ACROSS L.A. COUNTY SINCE
LAST NIGHT INTO EARLY THIS MORNING. HOWEVER...RAINFALL AMOUNTS HAVE
BEEN ANEMIC. WELL BELOW A TENTH OF AN INCH EVERYWHERE. THE UPPER LOW
WHICH IS CURRENTLY OFF THE SAN DIEGO COAST WILL BECOME MORE
ELONGATED AND STRETCH MORE NORTH TO SOUTH. THIS WILL ALLOW FOR MORE
CLOUD COVERAGE OVER MOST OF THE FORECAST AREA...ESPECIALLY THE
EASTERN HALF....WITH THE NORTHWESTERN PORTION LIKELY UNDER MOSTLY
SUNNY OR PARTLY CLOUDY SKIES TODAY.
SNOW LEVELS WILL REMAIN OVER 7000 FT TODAY...BUT SHOULD LOWER TO
6500 FT EARLY THIS EVENING. NOT EXPECTING MUCH OF ANY SNOWFALL WITH
THIS SYSTEM...BUT A FEW INCHES ABOVE 7000 FT IN THE EASTERN SAN
GABRIEL MOUNTAINS WILL BE POSSIBLE THROUGH SATURDAY MORNING.
HIGH TEMPS WILL BE A FEW DEGREES COOLER ACROSS THE BOARD
TODAY...ESPECIALLY OVER LA/VTU COUNTIES WITH MOSTLY CLOUDY SKIES. BY
TONIGHT MOST OF THE PRECIP WILL BE EAST AND SOUTH OF THE FORECAST
AREA. THERE WILL CONTINUE TO BE SOME LINGERING LOW LEVEL CLOUDS OVER
THE MOUNTAINS AND ANTELOPE VALLEY THROUGH EARLY SATURDAY
AFTERNOON...BUT SKIES SHOULD BEGIN TO CLEAR ACROSS COAST AND VALLEYS
BY LATE SAT MORNING. THERE WILL BE SOME INCREASING OFFSHORE WINDS
ACROSS LA/VTU MTNS AND WIND PRONE LA/VTU COUNTY PASSES AND CANYONS
AND ACROSS THE OXNARD PLAIN SATURDAY MORNING THROUGH MID AFTERNOON
HOURS. WINDS SHOULD REMAIN BELOW WIND ADVISORY THRESHOLDS. BUT WILL
BE CLOSE FOR THE MOUNTAINS AS THERE WILL BE A LIMITED WINDOW OF
UPPER LEVEL SUPPORT. NOT EXPECTING MUCH OF A WARM UP ON SATURDAY BUT
MAYBE A DEGREE OR TWO ALONG THE COAST AND COASTAL VALLEY AREAS DUE
TO OFFSHORE FLOW...ESPECIALLY THE CENTRAL COAST WITH EASTERLY FLOW
EXPECTED. BY SUNDAY THE UPPER LOW DROPS DOWN OVER BAJA WHILE A RIDGE
BUILDS IN FROM THE WEST. EXPECT BETTER WARMING ON SUNDAY ACROSS
COAST AND COASTAL VALLEYS INTO THE MID 70S WITH MOSTLY SUNNY SKIES.
NOT ANTICIPATING ANY MARINE LAYER STRATUS ISSUES...EXCEPT FOR LA
COUNTY COAST SATURDAY MORNING.
.LONG TERM (MON-THU)...ONCE THE UPPER LOW MOVES OUT OF THE REGION
STRONG UPPER LVL RIDGE WILL BUILD IN FROM THE SOUTHWEST OF
CALIFORNIA FOR MOST OF THE WEEK. THERE COULD BE A FEW HIGH CLOUDS
AROUND A DIRTY RIDGE TO AFFECT THE NORTHERN PORTION OF THE FORECAST
AREA...MAINLY N OF POINT CONCEPTION. NOT EXPECTING MUCH IN THE WAY
OF WINDS AS SURFACE PRESSURE GRADIENTS LOOK TO REMAIN PRETTY
NEUTRAL. THAT BEING SAID...THIS WILL ALLOW FOR SOME ADDITIONAL
WARMING UNDER THE DOME OF HIGH PRESSURE WITH HIGHS REACHING THE MID
TO UPPER 70S AND POSSIBLY AROUND 80 BY WED/THU. HAVE ADDED SOME
PATCHY LOW CLOUDS FOR THE CENTRAL COAST THU NIGHT INTO FRI MORNING
AS THE UPPER RIDGE WILL BEGIN TO FLATTEN SOME AND ONSHORE FLOW
SHOULD INCREASE. AT THIS POINT...IT LOOKS LIKE A SERIES OF STORMS
WILL AFFECT THE NORTHERN PORTION OF THE STATE BY LATE NEXT WEEK.
&&
.AVIATION...30/1045Z...
AT 0910Z...THERE WAS A SURFACE BASED INVERSION AT KLAX...WITH THE
INVERSION TOP AT 1100 FEET WITH A TEMPERATURES OF 18 DEGREES CELSIUS.
OVERALL...HIGH CONFIDENCE IN 12Z TAF PACKAGE. UPPER LOW SPINNING
SOUTH AND EAST OF THE AREA WILL CONTINUE TO STREAM IN A MID-LEVEL
CLOUD DECK ACROSS VENTURA/LOS ANGELES COUNTIES THROUGH THE TAF
PERIOD. THERE WILL BE THE OCCASIONAL LIGHT SHOWER ACROSS LOS ANGELES
COUNTY...BUT SHOWERS WILL BE VERY LIGHT. ELSEWHERE...THE ONLY ISSUE
THIS MORNING IS ANTICIPATED TO BE KPRB WHERE ANOTHER ROUND OF VLIFR
CONDS ARE ANTICIPATED THIS MORNING.
KLAX...HIGH CONFIDENCE IN 12Z TAF. VFR CIGS WILL CONTINUE THROUGH
THE TAF PERIOD...WITH THE POTENTIAL FOR AN OCCASIONAL LIGHT SHOWER.
LATE TONIGHT...MODERATE CONFIDENCE IN NORTHEAST WINDS AROUND 6 KNOTS
DEVELOPING.
KBUR...HIGH CONFIDENCE IN 12Z TAF. VFR CIGS WILL CONTINUE THROUGH
THE TAF PERIOD...WITH THE POTENTIAL FOR AN OCCASIONAL LIGHT SHOWER.
&&
.MARINE...30/900 AM...
SMALL CRAFT ADVISORY CONDITIONS FOR NORTHWEST WIND AND SEAS AROUND
10 FEET FROM PIEDRAS BLANCAS TO POINT SAL FROM 10-60 NM AND FROM THE
OUTER WATERS FROM POINT SAL TO SAN CLEMENTE ISLAND WILL LIKELY
PERSIST THROUGH SATURDAY MORNING. OTHERWISE A BROAD AREA OF LOW
PRESSURE WILL CONTINUE TO DEEPEN WHILE REMAINING NEARLY STATIONARY
OVER THE CENTRAL PACIFIC THROUGH SATURDAY EVENING AND THEN PERSIST
THROUGH SUNDAY. GALE FORCE WINDS WITHIN A FETCH AREA ORIENTED
BETWEEN 290-300 DEGREES RELATIVE TO VENTURA COUNTY IS EXPECTED TO
GENERATE SEAS AROUND 20 FEET. AND THE SWELLS FROM THE FETCH AREA ARE
EXPECTED TO ARRIVE NEXT WEEK TUESDAY AND REMAIN BELOW SCA FOR
HAZARDOUS SEAS.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...KAPLAN/SUKUP
AVIATION/MARINE...RAT/30
WWW.WEATHER.GOV/LOSANGELES
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
910 AM PST FRI JAN 30 2015
.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL BRING MOIST NORTHEAST FLOW INTO THE
SOUTHERN PORTION OF THE FORECAST AREA...WITH LIGHT RAIN SHOWERS
POSSIBLE. WEAK OFFSHORE WINDS WILL INCREASE BY SATURDAY NIGHT
THROUGH SUNDAY MORNING. HIGH PRESSURE WILL BRING WARMER TEMPERATURES
AND MOSTLY CLEAR SKIES OVER THE WEEKEND AND INTO NEXT WEEK.
&&
.SHORT TERM (TODAY-SUN)...
FORECAST THIS MORNING WAS IN PRETTY GOOD SHAPE. NO MAJOR CHANGES
MADE. JUST KEPT THE SLIGHT CHANCE OF SHOWERS GOING THIS AFTERNOON
FOR EASTERN PARTS OF VENTURA COUNTY. LATEST RADAR IMAGERY SHOWS A
DRYING TREND. THE HRRR DOES AS WELL...BUT IT ALSO SHOWS A LITTLE
FLARE UP OF SHOWER ACTIVITY THIS AFTERNOON...SO EASTERN VENTURA
COUNTY AND MUCH OF LA COUNTY COULD CONTINUE TO SEE ISOLATED TO
SCATTERED SHOWERS THIS AFTERNOON. RAINFALL AMOUNTS IN VENTURA AND LA
COUNTY HAVE BEEN LIGHT (GENERALLY LESS THAN 0.05"...EXCEPT SOME
0.25" AMOUNTS IN THE SAN GABRIELS). WITH WEAK OFFSHORE FLOW AND
PLENTY OF DRY AIR AT THE LOW LEVELS...ANY ADDITIONAL PRECIP WILL
CONTINUE TO BE VERY LIGHT. OVERALL TREND FOR THE NEXT 24-30 HOURS
WILL BE A DECREASE IN SHOWER ACTIVITY AS THE UPPER LOW DRIFTS TO THE
SOUTHEAST.
***FROM PREVIOUS DISCUSSION***
SCATTERED LIGHT SHOWERS HAVE BEEN OCCURRING ACROSS L.A. COUNTY SINCE
LAST NIGHT INTO EARLY THIS MORNING. HOWEVER...RAINFALL AMOUNTS HAVE
BEEN ANEMIC. WELL BELOW A TENTH OF AN INCH EVERYWHERE. THE UPPER LOW
WHICH IS CURRENTLY OFF THE SAN DIEGO COAST WILL BECOME MORE
ELONGATED AND STRETCH MORE NORTH TO SOUTH. THIS WILL ALLOW FOR MORE
CLOUD COVERAGE OVER MOST OF THE FORECAST AREA...ESPECIALLY THE
EASTERN HALF....WITH THE NORTHWESTERN PORTION LIKELY UNDER MOSTLY
SUNNY OR PARTLY CLOUDY SKIES TODAY.
SNOW LEVELS WILL REMAIN OVER 7000 FT TODAY...BUT SHOULD LOWER TO
6500 FT EARLY THIS EVENING. NOT EXPECTING MUCH OF ANY SNOWFALL WITH
THIS SYSTEM...BUT A FEW INCHES ABOVE 7000 FT IN THE EASTERN SAN
GABRIEL MOUNTAINS WILL BE POSSIBLE THROUGH SATURDAY MORNING.
HIGH TEMPS WILL BE A FEW DEGREES COOLER ACROSS THE BOARD
TODAY...ESPECIALLY OVER LA/VTU COUNTIES WITH MOSTLY CLOUDY SKIES. BY
TONIGHT MOST OF THE PRECIP WILL BE EAST AND SOUTH OF THE FORECAST
AREA. THERE WILL CONTINUE TO BE SOME LINGERING LOW LEVEL CLOUDS OVER
THE MOUNTAINS AND ANTELOPE VALLEY THROUGH EARLY SATURDAY
AFTERNOON...BUT SKIES SHOULD BEGIN TO CLEAR ACROSS COAST AND VALLEYS
BY LATE SAT MORNING. THERE WILL BE SOME INCREASING OFFSHORE WINDS
ACROSS LA/VTU MTNS AND WIND PRONE LA/VTU COUNTY PASSES AND CANYONS
AND ACROSS THE OXNARD PLAIN SATURDAY MORNING THROUGH MID AFTERNOON
HOURS. WINDS SHOULD REMAIN BELOW WIND ADVISORY THRESHOLDS. BUT WILL
BE CLOSE FOR THE MOUNTAINS AS THERE WILL BE A LIMITED WINDOW OF
UPPER LEVEL SUPPORT. NOT EXPECTING MUCH OF A WARM UP ON SATURDAY BUT
MAYBE A DEGREE OR TWO ALONG THE COAST AND COASTAL VALLEY AREAS DUE
TO OFFSHORE FLOW...ESPECIALLY THE CENTRAL COAST WITH EASTERLY FLOW
EXPECTED. BY SUNDAY THE UPPER LOW DROPS DOWN OVER BAJA WHILE A RIDGE
BUILDS IN FROM THE WEST. EXPECT BETTER WARMING ON SUNDAY ACROSS
COAST AND COASTAL VALLEYS INTO THE MID 70S WITH MOSTLY SUNNY SKIES.
NOT ANTICIPATING ANY MARINE LAYER STRATUS ISSUES...EXCEPT FOR LA
COUNTY COAST SATURDAY MORNING.
.LONG TERM (MON-THU)...ONCE THE UPPER LOW MOVES OUT OF THE REGION
STRONG UPPER LVL RIDGE WILL BUILD IN FROM THE SOUTHWEST OF
CALIFORNIA FOR MOST OF THE WEEK. THERE COULD BE A FEW HIGH CLOUDS
AROUND A DIRTY RIDGE TO AFFECT THE NORTHERN PORTION OF THE FORECAST
AREA...MAINLY N OF POINT CONCEPTION. NOT EXPECTING MUCH IN THE WAY
OF WINDS AS SURFACE PRESSURE GRADIENTS LOOK TO REMAIN PRETTY
NEUTRAL. THAT BEING SAID...THIS WILL ALLOW FOR SOME ADDITIONAL
WARMING UNDER THE DOME OF HIGH PRESSURE WITH HIGHS REACHING THE MID
TO UPPER 70S AND POSSIBLY AROUND 80 BY WED/THU. HAVE ADDED SOME
PATCHY LOW CLOUDS FOR THE CENTRAL COAST THU NIGHT INTO FRI MORNING
AS THE UPPER RIDGE WILL BEGIN TO FLATTEN SOME AND ONSHORE FLOW
SHOULD INCREASE. AT THIS POINT...IT LOOKS LIKE A SERIES OF STORMS
WILL AFFECT THE NORTHERN PORTION OF THE STATE BY LATE NEXT WEEK.
&&
.AVIATION...30/1045Z...
AT 0910Z...THERE WAS A SURFACE BASED INVERSION AT KLAX...WITH THE
INVERSION TOP AT 1100 FEET WITH A TEMPERATURES OF 18 DEGREES CELSIUS.
OVERALL...HIGH CONFIDENCE IN 12Z TAF PACKAGE. UPPER LOW SPINNING
SOUTH AND EAST OF THE AREA WILL CONTINUE TO STREAM IN A MID-LEVEL
CLOUD DECK ACROSS VENTURA/LOS ANGELES COUNTIES THROUGH THE TAF
PERIOD. THERE WILL BE THE OCCASIONAL LIGHT SHOWER ACROSS LOS ANGELES
COUNTY...BUT SHOWERS WILL BE VERY LIGHT. ELSEWHERE...THE ONLY ISSUE
THIS MORNING IS ANTICIPATED TO BE KPRB WHERE ANOTHER ROUND OF VLIFR
CONDS ARE ANTICIPATED THIS MORNING.
KLAX...HIGH CONFIDENCE IN 12Z TAF. VFR CIGS WILL CONTINUE THROUGH
THE TAF PERIOD...WITH THE POTENTIAL FOR AN OCCASIONAL LIGHT SHOWER.
LATE TONIGHT...MODERATE CONFIDENCE IN NORTHEAST WINDS AROUND 6 KNOTS
DEVELOPING.
KBUR...HIGH CONFIDENCE IN 12Z TAF. VFR CIGS WILL CONTINUE THROUGH
THE TAF PERIOD...WITH THE POTENTIAL FOR AN OCCASIONAL LIGHT SHOWER.
&&
.MARINE...30/215 AM...
FOR THE OUTER WATERS...MODERATE TO HIGH CONFIDENCE IN SMALL CRAFT
ADVISORY-LEVEL NORTHWEST WINDS DEVELOPING TODAY AND CONTINUING
THROUGH TONIGHT. ON SATURDAY...NORTHWEST WINDS WILL DIMINISH WITH
ONLY LOCAL GUSTS TO 25 KNOTS EXPECTED. FOR SUNDAY THROUGH EARLY NEXT
WEEK...HIGH CONFIDENCE IN WINDS REMAINING BELOW SMALL CRAFT ADVISORY
LEVELS.
FOR THE INNER WATERS...MODERATE CONFIDENCE IN WINDS REMAINING BELOW
SMALL CRAFT ADVISORY LEVELS THROUGH SUNDAY. THERE WILL BE A 30%
CHANCE OF NORTHEAST WINDS REACHING SMALL CRAFT ADVISORY LEVELS LATE
TONIGHT/SATURDAY AND AGAIN LATE SATURDAY NIGHT/SUNDAY NEAR SHORE
FROM VENTURA SOUTH TO SANTA MONICA. FOR EARLY NEXT WEEK...WINDS
ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
&&
$$
PUBLIC...KAPLAN/SUKUP
AVIATION/MARINE...RAT
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION...UPDATED
NWS SAN JOAQUIN VALLEY - HANFORD CA
955 PM PST THU JAN 29 2015
.UPDATE...
INCREASED POPS TONIGHT AND FRIDAY MORNING FOR THE SOUTH END OF
THE SAN JOAQUIN VALLEY AND THE ADJACENT MOUNTAINS AND FOOTHILLS.
&&
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL BRING A CHANCE OF LIGHT SHOWERS TO MAINLY
THE MOUNTAINS AND DESERT TONIGHT THROUGH SATURDAY MORNING. OTHERWISE
EXPECT DRY CONDITIONS WITH NEAR TO SLIGHTLY ABOVE AVERAGE
TEMPERATURES THROUGH THE NEXT SEVERAL DAYS WITH PATCHY FOG THROUGH
THE SAN JOAQUIN VALLEY EACH NIGHT AND EARLY MORNING.
&&
.UPDATED DISCUSSION...
CLOUDS CONTINUE TO PUSH INTO SOUTHERN KERN COUNTY AND THE TULARE
COUNTY MOUNTAINS THIS EVENING. EDWARDS AFB ALREADY HAS REPORTED A
TRACE OF RAIN...AND RECEIVED A MEDIA REPORT OF RAIN IN ARVIN IN THE
SOUTH END OF THE SAN JOAQUIN VALLEY. HAVE UPDATED THE FORECAST TO
FURTHER INCREASE POPS OVER SOUTHERN KERN COUNTY AND TO INCLUDE THE
SOUTH END OF THE SAN JOAQUIN VALLEY AND THE TULARE COUNTY MOUNTAINS
AND FOOTHILLS IN THE SLIGHT CHANCE POP CATEGORY THROUGH FRIDAY
MORNING.
&&
.DISCUSSION...
AN UPPER-LEVEL LOW LOCATED WEST OF NORTHERN BAJA CALIFORNIA WAS
SPINNING MID AND HIGH CLOUDS OVER SOUTHERN CALIFORNIA THIS
EVENING. BASED ON A REPORT OF SPRINKLES IN DOWNTOWN LOS ANGELES...
CANNOT RULE OUT ENOUGH OROGRAPHIC FORCING FOR A LIGHT SHOWER OR
TWO OVER THE KERN COUNTY MOUNTAINS AND DESERT AREAS OVERNIGHT INTO
FRIDAY MORNING. HAVE INCREASED POPS OVER THE KERN DESERT...INDIAN
WELLS VALLEY...THE TEHACHAPI MOUNTAINS AND THE PIUTES THROUGH 18Z
/1000 PST/ FRIDAY MORNING.
THE OTHER CONCERN THIS EVENING IS THE DEVELOPMENT OF THE TULE FOG
IN THE CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY. AT 0335Z FRIDAY
/1935 PST THIS EVENING/...THE VISIBILITY AT THE CASTLE AIRPARK HAD
ALREADY FALLEN BELOW 1/4 MILE...WITH THE MADERA MUNICIPAL AIRPORT
/KMAE/ FALLING BELOW A QUARTER MILE AT 0441Z FRIDAY /2041 PST
TONIGHT/...AND THE MERCED REGIONAL AIRPORT /KMCE/ DROPPING BELOW
A QUARTER MILE AT 0453Z FRIDAY /2053 PST TONIGHT/. THE START TIME
FOR THE CURRENT DENSE FOG ADVISORY OF 04Z FRIDAY /2000 PST
TONIGHT/ WAS VERIFYING NICELY.
&&
.PREV DISCUSSION... /ISSUED 530 PM PST THU JAN 29 2015/
DISCUSSION...
VISIBLE SATELLITE IMAGERY IS SHOWING MID/HIGH CLOUDS THINNING
ACROSS THE CENTRAL CALIFORNIA INTERIOR...NOW MAINLY JUST OVER
TULARE AND KERN COUNTIES. PATCHES OF TULE FOG LINGERED ACROSS THE
CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY INTO THE EARLY AFTERNOON
WITH HAZY CONDITIONS PREVAILING NOW. WITH THE SKIES CLEARING AND
VIRTUALLY NO CHANGE IN BOUNDARY LAYER CONDITIONS...A REPEAT OF THE
DENSE FOG LOOKS VERY LIKELY TONIGHT. THE HRRR MODEL SHOWS
DEVELOPMENT OF FOG BEGINNING AROUND 04Z WHICH IS ABOUT THE TIME AS
LAST NIGHT. WILL ISSUE A DENSE FOG ADVISORY FOR THE SJV FROM 04Z-
20Z FRIDAY... /8 PM TONIGHT THROUGH NOON FRIDAY/.
A WEAK UPPER TROUGH IS MOVING OVER CENTRAL CALIFORNIA TODAY AND
BENEATH THE HIGHER CLOUDS ARE SOME SHALLOW CUMULUS OVER THE SOUTHERN
SIERRA NEVADA. SOME ISOLATED SHOWER ACTIVITY HAS DEVELOPED OVER
THE TULARE COUNTY MOUNTAINS WITH A FEW HUNDREDTHS OF AN INCH MEASURED
AT A COUPLE AUTOMATED GAUGES. WEB CAMS OVER THE SIERRA ARE SHOWING
THIS ACTIVITY AS WELL WITH BRIEF RAIN SHAFTS VISIBLE. THE BASE OF
THE ELONGATED TROUGH IS WEST OF BAJA CALIFORNIA AND THIS WILL LIFT
NORTHEAST OVERNIGHT AND FORM A CLOSED LOW OVER SOCAL ON FRIDAY.
THIS WILL BRING A CONTINUED CHANCE OF LIGHT SHOWERS FOR THE SIERRA
AND BRING A CHANCE TO THE KERN COUNTY MOUNTAINS AND DESERT AS WELL
THROUGH FRIDAY NIGHT. THERE IS NOT MUCH MOISTURE TO WORK WITH SO
QPF AMOUNTS REMAIN LIGHT. THE LOW IS EXPECTED TO DRIFT SOUTH ON
SATURDAY WITH UPPER RIDGING BUILDING IN OVER CALIFORNIA DURING THE
WEEKEND. A WEAK TROUGH PASSING OVER THE PACNW WILL FLATTEN THE RIDGE
ON MONDAY THEN IT AMPLIFIES OVER THE WEST COAST THROUGH MIDWEEK.
SO AFTER A COUPLE OF DAYS OF LIGHT SHOWERS FOR THE MOUNTAINS...DRY
WEATHER IS EXPECTED TO RETURN THIS WEEKEND AND WILL LIKELY CONTINUE
THROUGH NEXT WEEK.
TEMPERATURES WILL HOVER CLOSE TO NORMAL THROUGH SATURDAY THEN WARM
TO A LITTLE ABOVE NORMAL NEXT WEEK. HOWEVER...THE UPPER RIDGE WILL
LEAD TO A STRENGTHENING INVERSION AND TULE FOG IS EXPECTED TO OCCUR
EACH NIGHT ACROSS THE SJV. THE FOG MAY BE SLOW TO BREAK AND IF THICK
ENOUGH...COULD JUST LIFT INTO A LOW STRATUS DECK DURING THE AFTERNOON.
THIS MAKES HIGH TEMPERATURE FORECASTS LESS CERTAIN FOR THE SJV.
&&
.AVIATION...
AREAS MVFR VISIBILITIES IN THE SAN JOAQUIN VALLEY...BECOMING AREAS
OF IFR WITH LOCAL VLIFR CONDITIONS IN FOG UNTIL 20Z FRIDAY. POSSIBLE
AREAS OF MOUNTAIN OBSCURATION OVER THE TEHACHAPI RANGE AND SIERRA
NEVADA IN SHOWERS UNTIL 06Z SATURDAY. OTHERWISE...VFR CONDITIONS FOR
THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
ON FRIDAY JANUARY 30 2015... UNHEALTHY FOR SENSITIVE GROUPS IN
KERN AND TULARE COUNTIES. FIREPLACE/WOOD STOVE BURNING STATUS IS:
NO BURNING UNLESS REGISTERED IN FRESNO... KERN... KINGS...
MADERA... MERCED AND TULARE COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS MEDIUM.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 01-29 73:1960 43:2002 55:1911 24:1902
KFAT 01-30 74:1984 41:1923 56:1911 25:1946
KFAT 01-31 75:1984 39:1969 55:1963 26:1949
KBFL 01-29 74:1986 42:2002 54:1986 27:1903
KBFL 01-30 77:1911 44:1951 60:1911 23:1902
KBFL 01-31 82:1984 45:1969 57:1963 23:1902
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON PST FRIDAY FOR THE CENTRAL AND
SOUTHERN SAN JOAQUIN VALLEY /CAZ089>092/.
&&
$$
PUBLIC...SANGER
AVN/FW...MOLINA
PREV DISCUSSION...DCH
SYNOPSIS...DCH
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION...UPDATED
NWS SAN JOAQUIN VALLEY - HANFORD CA
910 PM PST THU JAN 29 2015
.UPDATE...
INCREASED POPS TONIGHT AND FRIDAY MORNING FOR THE KERN COUNTY
MOUNTAINS AND DESERTS.
&&
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL BRING A CHANCE OF LIGHT SHOWERS TO MAINLY
THE MOUNTAINS AND DESERT TONIGHT THROUGH SATURDAY MORNING. OTHERWISE
EXPECT DRY CONDITIONS WITH NEAR TO SLIGHTLY ABOVE AVERAGE
TEMPERATURES THROUGH THE NEXT SEVERAL DAYS WITH PATCHY FOG THROUGH
THE SAN JOAQUIN VALLEY EACH NIGHT AND EARLY MORNING.
&&
.DISCUSSION...
AN UPPER-LEVEL LOW LOCATED WEST OF NORTHERN BAJA CALIFORNIA WAS
SPINNING MID AND HIGH CLOUDS OVER SOUTHERN CALIFORNIA THIS
EVENING. BASED ON A REPORT OF SPRINKLES IN DOWNTOWN LOS ANGELES...
CANNOT RULE OUT ENOUGH OROGRAPHIC FORCING FOR A LIGHT SHOWER OR
TWO OVER THE KERN COUNTY MOUNTAINS AND DESERT AREAS OVERNIGHT INTO
FRIDAY MORNING. HAVE INCREASED POPS OVER THE KERN DESERT...INDIAN
WELLS VALLEY...THE TEHACHAPI MOUNTAINS AND THE PIUTES THROUGH 18Z
/1000 PST/ FRIDAY MORNING.
THE OTHER CONCERN THIS EVENING IS THE DEVELOPMENT OF THE TULE FOG
IN THE CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY. AT 0335Z FRIDAY
/1935 PST THIS EVENING/...THE VISIBILITY AT THE CASTLE AIRPARK HAD
ALREADY FALLEN BELOW 1/4 MILE...WITH THE MADERA MUNICIPAL AIRPORT
/KMAE/ FALLING BELOW A QUARTER MILE AT 0441Z FRIDAY /2041 PST
TONIGHT/...AND THE MERCED REGIONAL AIRPORT /KMCE/ DROPPING BELOW
A QUARTER MILE AT 0453Z FRIDAY /2053 PST TONIGHT/. THE START TIME
FOR THE CURRENT DENSE FOG ADVISORY OF 04Z FRIDAY /2000 PST
TONIGHT/ WAS VERIFYING NICELY.
&&
.PREV DISCUSSION... /ISSUED 530 PM PST THU JAN 29 2015/
DISCUSSION...
VISIBLE SATELLITE IMAGERY IS SHOWING MID/HIGH CLOUDS THINNING
ACROSS THE CENTRAL CALIFORNIA INTERIOR...NOW MAINLY JUST OVER
TULARE AND KERN COUNTIES. PATCHES OF TULE FOG LINGERED ACROSS THE
CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY INTO THE EARLY AFTERNOON
WITH HAZY CONDITIONS PREVAILING NOW. WITH THE SKIES CLEARING AND
VIRTUALLY NO CHANGE IN BOUNDARY LAYER CONDITIONS...A REPEAT OF THE
DENSE FOG LOOKS VERY LIKELY TONIGHT. THE HRRR MODEL SHOWS
DEVELOPMENT OF FOG BEGINNING AROUND 04Z WHICH IS ABOUT THE TIME AS
LAST NIGHT. WILL ISSUE A DENSE FOG ADVISORY FOR THE SJV FROM 04Z-
20Z FRIDAY... /8 PM TONIGHT THROUGH NOON FRIDAY/.
A WEAK UPPER TROUGH IS MOVING OVER CENTRAL CALIFORNIA TODAY AND
BENEATH THE HIGHER CLOUDS ARE SOME SHALLOW CUMULUS OVER THE SOUTHERN
SIERRA NEVADA. SOME ISOLATED SHOWER ACTIVITY HAS DEVELOPED OVER
THE TULARE COUNTY MOUNTAINS WITH A FEW HUNDREDTHS OF AN INCH MEASURED
AT A COUPLE AUTOMATED GAUGES. WEB CAMS OVER THE SIERRA ARE SHOWING
THIS ACTIVITY AS WELL WITH BRIEF RAIN SHAFTS VISIBLE. THE BASE OF
THE ELONGATED TROUGH IS WEST OF BAJA CALIFORNIA AND THIS WILL LIFT
NORTHEAST OVERNIGHT AND FORM A CLOSED LOW OVER SOCAL ON FRIDAY.
THIS WILL BRING A CONTINUED CHANCE OF LIGHT SHOWERS FOR THE SIERRA
AND BRING A CHANCE TO THE KERN COUNTY MOUNTAINS AND DESERT AS WELL
THROUGH FRIDAY NIGHT. THERE IS NOT MUCH MOISTURE TO WORK WITH SO
QPF AMOUNTS REMAIN LIGHT. THE LOW IS EXPECTED TO DRIFT SOUTH ON
SATURDAY WITH UPPER RIDGING BUILDING IN OVER CALIFORNIA DURING THE
WEEKEND. A WEAK TROUGH PASSING OVER THE PACNW WILL FLATTEN THE RIDGE
ON MONDAY THEN IT AMPLIFIES OVER THE WEST COAST THROUGH MIDWEEK.
SO AFTER A COUPLE OF DAYS OF LIGHT SHOWERS FOR THE MOUNTAINS...DRY
WEATHER IS EXPECTED TO RETURN THIS WEEKEND AND WILL LIKELY CONTINUE
THROUGH NEXT WEEK.
TEMPERATURES WILL HOVER CLOSE TO NORMAL THROUGH SATURDAY THEN WARM
TO A LITTLE ABOVE NORMAL NEXT WEEK. HOWEVER...THE UPPER RIDGE WILL
LEAD TO A STRENGTHENING INVERSION AND TULE FOG IS EXPECTED TO OCCUR
EACH NIGHT ACROSS THE SJV. THE FOG MAY BE SLOW TO BREAK AND IF THICK
ENOUGH...COULD JUST LIFT INTO A LOW STRATUS DECK DURING THE AFTERNOON.
THIS MAKES HIGH TEMPERATURE FORECASTS LESS CERTAIN FOR THE SJV.
&&
.AVIATION...
AREAS MVFR VISIBILITIES IN THE SAN JOAQUIN VALLEY...BECOMING AREAS
OF IFR WITH LOCAL VLIFR CONDITIONS IN FOG UNTIL 20Z FRIDAY. POSSIBLE
AREAS OF MOUNTAIN OBSCURATION OVER THE TEHACHAPI RANGE AND SIERRA
NEVADA IN SHOWERS UNTIL 06Z SATURDAY. OTHERWISE...VFR CONDITIONS FOR
THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
ON FRIDAY JANUARY 30 2015... UNHEALTHY FOR SENSITIVE GROUPS IN
KERN AND TULARE COUNTIES. FIREPLACE/WOOD STOVE BURNING STATUS IS:
NO BURNING UNLESS REGISTERED IN FRESNO... KERN... KINGS...
MADERA... MERCED AND TULARE COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS MEDIUM.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 01-29 73:1960 43:2002 55:1911 24:1902
KFAT 01-30 74:1984 41:1923 56:1911 25:1946
KFAT 01-31 75:1984 39:1969 55:1963 26:1949
KBFL 01-29 74:1986 42:2002 54:1986 27:1903
KBFL 01-30 77:1911 44:1951 60:1911 23:1902
KBFL 01-31 82:1984 45:1969 57:1963 23:1902
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL NOON PST FRIDAY FOR THE CENTRAL AND
SOUTHERN SAN JOAQUIN VALLEY /CAZ089>092/.
&&
$$
PUBLIC...SANGER
AVN/FW...MOLINA
PREV DISCUSSION...DCH
SYNOPSIS...DCH
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS PUEBLO CO
812 PM MST SAT JAN 31 2015
.UPDATE...
ISSUED AT 809 PM MST SAT JAN 31 2015
UPDATED FORECAST TO ACCOUNT FOR RADAR TRENDS OVER EASTERN PLAINS
AN PRECIP DROPPING SOUTH TOWARDS THE PIKES PEAK REGION. ALSO
EXPIRING SNOW ADVISORIES FOR PARTS OF THE HIGH COUNTRY. /HODANISH
UPDATE ISSUED AT 447 PM MST SAT JAN 31 2015
FINE-TUNED FORECAST FOR LATEST RADAR TRENDS AND HRRR FCST. FIRST
BAND OF PRECIP WILL MOVE ACROSS THE REGION EARLY THIS EVENING
WITH ANOTHER BAND COMING ACROSS MAINLY THE PIKES PEAK REGION
TOWARDS MIDNIGHT. FIRST BAND ALREADY CLEARED C MTNS AND WILL
REMOVE SNOW ADVISORY FROM THIS REGION WITH THIS UPDATE.
UPDATE WILL BE ISSUED SHORTLY AFTER 5 PM. /HODANISH
/HODANISH
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 236 PM MST SAT JAN 31 2015
CURRENTLY...PRECIP EXPANDING ACROSS THE AREA AS LIFT INCREASES AHEAD
OF UPPER TROUGH DROPPING SOUTHWARD THROUGH THE NRN ROCKIES. SURFACE
COLD FRONT WAS ALONG THE PALMER DIVIDE AS OF 21Z...WITH PRECIP
EXPECTED TO EXPAND ALONG/BEHIND THE BOUNDARY INTO EARLY EVENING AS
IT DROPS SOUTH TOWARD THE NM BORDER. WARMER TEMPS HAVE HELD ON AHEAD
OF THE FRONT ALONG AND SOUTH OF THE ARKANSAS RIVER...AND EXPECT
PRECIP TO BEGIN AS RAIN BELOW ABOUT 6K FEET LATE THIS AFTERNOON.
FARTHER WEST..SNOW CONTINUES ACROSS THE HIGHER ELEVATIONS AND MOST
VALLEYS...THOUGH BACK EDGE OF STEADIER SNOW WAS ALREADY MOVING
TOWARD THE CENTRAL MOUNTAINS AS OF 21Z.
TONIGHT...LEFT CURRENT ROUND OF WINTER HIGHLIGHTS INTACT...THOUGH
WITH BACK EDGE OF SNOW DROPPING SOUTH OF I-70 ALREADY...CENTRAL
MOUNTAIN ADVISORY MAY NEED TO BE DROPPED EARLY WITH NEXT UPDATE.
ELSEWHERE...EXPECT A PERIOD OF SNOW OVER MOST MOUNTAINS AND HIGH
VALLEYS THROUGH THE EVENING...WITH FOCUS OF HEAVIER SNOW SHIFTING TO
THE EASTERN MOUNTAINS AS FLOW BECOMES WEAKLY UPSLOPE. HIGHER
PEAKS OF THE SANGRES/WETS/PIKES PEAK WILL SEE SOME MODEST (2-5 INCH)
ACCUMULATIONS THIS EVENING...WHILE VALLEYS SEE A QUICK INCH OR TWO.
PRECIP ON THE PLAINS BELOW ABOUT 6K FEET WILL START AS RAIN...WITH A
GRADUAL CHANGE OVER TO SNOW AFTER SUNSET AS COLDER AIR AT THE
SURFACE AND ALOFT SPREADS SOUTH. LATE CHANGEOVER AND WARM GROUND
WILL LIMIT ACCUMS ON THE PLAINS...THOUGH EL PASO COUNTY COULD SEE A
INCH OR TWO ONCE TEMPS DROP BELOW FREEZING AFTER SUNSET. PAST 04Z-
06Z...LIFT DECREASES OVER MOUNTAINS/WRN VALLEYS AS TROUGH DROPS
SOUTH...WITH SNOW FADING AWAY FAIRLY QUICKLY BY LATE EVENING.
EASTERN MOUNTAINS WILL LIKELY HOLD ON TO SNOW LONGER AS WEAK
UPSLOPE COMPONENT KEEPS AT LEAST SOME LIGHT SNOW GOING INTO SUN
MORNING. OVERNIGHT LOWS WILL DROP BELOW FREEZING MOST LOCATIONS AS
DRIER/COLDER AIR FILTERS SOUTH THROUGH THE NIGHT.
SUNDAY...STILL SOME LINGERING LIGHT SNOW ALONG/WEST OF I-25 IN THE
MORNING...GRADUALLY FADING TO FLURRIES IN THE AFTERNOON AS UPSLOPE
FADES AND UPPER JET SHIFTS INTO THE CENTRAL PLAINS. DESPITE SOME SUN
MANY AREAS BY AFTERNOON...CONTINUED COLD ADVECTION WILL KEEP TEMPS
FAIRLY COOL WITH MOST LOCATIONS IN THE 30S OR COLDER.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 236 PM MST SAT JAN 31 2015
MODELS CONTINUE TO HAVE DIFFERENCES IN THE MIDDLE OF THE EXTENDED
PERIOD WITH THE ECMWF HAVE BETTER ENSEMBLE SUPPORT THAN THE GFS
SOLUTION.
SUNDAY NIGHT THROUGH TUESDAY...THE UPPER PATTERN WILL FEATURE A
TROUGH MOVING OFF TO THE EAST WHILE AN UPPER RIDGE DEVELOPS ALONG
THE WEST COAST. THIS WILL PUT SOUTHERN COLORADO UNDER BROAD
NORTHWESTERLY FLOW ALOFT. SNOW WILL BE WINDING DOWN OVER THE
SOUTHERN SANGRE DE CRISTO MOUNTAINS SUNDAY EVENING WITH DRY
CONDITIONS EXPECTED ACROSS MOST OF THE REGION BY MONDAY MORNING.
THE EXCEPTION WILL BE THE CENTRAL MOUNTAINS. THE PERSISTENT
NORTHWESTERLY FLOW IS FAVORED OROGRAPHICALLY AND CONTINUOUS LIGHT
SNOW WILL PREVAIL OVER THE CENTRAL MOUNTAINS THROUGH TUESDAY
NIGHT. ACCUMULATIONS OF 3 TO 6 INCHES WITH LOCALLY HIGHER
AMOUNTS ARE POSSIBLE SUNDAY NIGHT THROUGH TUESDAY NIGHT. DRY
CONDITIONS WILL PREVAIL ACROSS THE EASTERN PLAINS. MIXING OF
NORTHWESTERLY FLOW WILL BRING WARMING TEMPERATURES TO THE LOWER
ELEVATIONS...WITH 50S FOR HIGHS ON MONDAY...AND 60S ON TUESDAY.
WEDNESDAY...MODELS CONTINUE TO STRUGGLE WITH THE NEXT WEATHER
SYSTEM EXPECTED TO REACH THE AREA ON WEDNESDAY. THE GFS IS THE
MOST AGGRESSIVE WITH THIS SHORTWAVE TROUGH...WHICH IS FORECAST TO
DROP SOUTH OUT OF THE NORTHERN ROCKIES. THE GFS DROPS A COLD
FRONT ACROSS EASTERN COLORADO AND DEVELOPS WIDESPREAD RAIN
CHANGING TO SNOW WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT BEFORE
CLEARING THE AREA BY THURSDAY MORNING. THE ECMWF...WHICH HAS
BETTER ENSEMBLE SUPPORT...IS MUCH DIFFERENT THAN THE GFS. IT TAKES
THE UPPER LEVEL SHORTWAVE TROUGH OUT OF MONTANA...AND BARELY CLIPS
NORTHEAST COLORADO AS IT TRACKS INTO THE CENTRAL PLAINS. IT ALSO
HAS A COLD FRONT BY WEDNESDAY EVENING OVER THE PLAINS...BUT DOES
NOT HAVE MUCH IN THE WAY OF PRECIPITATION ACROSS THE REGION. IT
HAS SNOW OVER THE CENTRAL MOUNTAINS...AND PERHAPS THE PALMER
DIVIDE WEDNESDAY NIGHT...BUT KEEPS THE EASTERN PLAINS DRY. FOR NOW
HAVE LOW POPS ACROSS THE PLAINS...BUT CONFIDENCE IS LOW AT THIS
TIME. TEMPERATURES ON WEDNESDAY WILL DEPEND ON FRONTAL TIMING WITH
40S TO LOWER 50S EXPECTED.
THURSDAY THROUGH SATURDAY...BROAD NORTHWESTERLY FLOW WILL
REDEVELOP ACROSS THE REGION AS HIGH PRESSURE OVER THE WEST MOVES
SLOWLY EASTWARD. LIGHT SNOW OVER THE CENTRAL MOUNTAINS IS FORECAST
TO DISSIPATE BY FRIDAY AS DRIER AIR ALOFT MOVES INTO THE AREA.
TEMPERATURES WILL ALSO REBOUND WITH 50S AND 60S BY FRIDAY AND
SATURDAY. MOZLEY
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 236 PM MST SAT JAN 31 2015
AT KALS...IFR STRATUS HAS LIFTED WITH THE ONSET OF LIGHT
SNOW...THOUGH VISIBILITY HAS GONE IFR UNDER SOME PERSISTENT SNOW
SHOWERS AS OF 22Z. IN GENERAL...EXPECT MVFR CONDITIONS THROUGH THE
EVENING WITH PERIODS OF IFR UNDER HEAVIER SNOW SHOWERS UNTIL 06Z-
08Z. DRIER AIR THEN BEGINS TO MOVE ACROSS THE VALLEY WITH CIGS
LIFTING/DISSIPATING...THOUGH SOME PATCHY GROUND FOG MAY MAKE A
BRIEF APPEARANCE AROUND SUNRISE. ON SUNDAY...VFR.
AT KCOS...EXPECT IFR/BRIEFLY LIFR CONDITIONS WITH LIGHT SNOW
AND LOW CIGS INTO THE EVENING UNTIL 04Z-05Z...THEN VIS IMPROVES AND
CIGS LIFT SLIGHTLY AFTER ABOUT 06Z...THOUGH PATCHY MVFR STRATUS MAY
LINGER THROUGH MID-MORNING SUNDAY. AFTER 16Z SUN...CIGS WILL BECOME
VFR.
AT KPUB...EXPECT A PERIOD OF MVFR CIGS AND VIS THIS EVENING AS COLD
FRONT PASSES AND -SHRA/-SHSN DEVELOP. SHOWERS END 06Z-08Z WITH
LINGERING MVFR STRATUS UNTIL MID-MORNING SUNDAY...THEN VFR.
OVER THE MOUNTAINS...MOST HIGHER TERRAIN WILL BE OBSCURED BY
CLOUDS AND SNOW SHOWERS TODAY AND TONIGHT...WITH SOME CLEARING
WORKING FROM WEST TO EAST LATE TONIGHT INTO MID MORNING SUNDAY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR COZ074-
075.
&&
$$
UPDATE...HODANISH
SHORT TERM...PETERSEN
LONG TERM...MOZLEY
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
450 PM MST SAT JAN 31 2015
.UPDATE...
ISSUED AT 447 PM MST SAT JAN 31 2015
FINE-TUNED FORECAST FOR LATEST RADAR TRENDS AND HRRR FCST. FIRST
BAND OF PRECIP WILL MOVE ACROSS THE REGION EARLY THIS EVENING
WITH ANOTHER BAND COMING ACROSS MAINLY THE PIKES PEAK REGION
TOWARDS MIDNIGHT. FIRST BAND ALREADY CLEARED C MTNS AND WILL
REMOVE SNOW ADVISORY FROM THIS REGION WITH THIS UPDATE.
UPDATE WILL BE ISSUED SHORTLY AFTER 5 PM. /HODANISH
/HODANISH
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 236 PM MST SAT JAN 31 2015
CURRENTLY...PRECIP EXPANDING ACROSS THE AREA AS LIFT INCREASES AHEAD
OF UPPER TROUGH DROPPING SOUTHWARD THROUGH THE NRN ROCKIES. SURFACE
COLD FRONT WAS ALONG THE PALMER DIVIDE AS OF 21Z...WITH PRECIP
EXPECTED TO EXPAND ALONG/BEHIND THE BOUNDARY INTO EARLY EVENING AS
IT DROPS SOUTH TOWARD THE NM BORDER. WARMER TEMPS HAVE HELD ON AHEAD
OF THE FRONT ALONG AND SOUTH OF THE ARKANSAS RIVER...AND EXPECT
PRECIP TO BEGIN AS RAIN BELOW ABOUT 6K FEET LATE THIS AFTERNOON.
FARTHER WEST..SNOW CONTINUES ACROSS THE HIGHER ELEVATIONS AND MOST
VALLEYS...THOUGH BACK EDGE OF STEADIER SNOW WAS ALREADY MOVING
TOWARD THE CENTRAL MOUNTAINS AS OF 21Z.
TONIGHT...LEFT CURRENT ROUND OF WINTER HIGHLIGHTS INTACT...THOUGH
WITH BACK EDGE OF SNOW DROPPING SOUTH OF I-70 ALREADY...CENTRAL
MOUNTAIN ADVISORY MAY NEED TO BE DROPPED EARLY WITH NEXT UPDATE.
ELSEWHERE...EXPECT A PERIOD OF SNOW OVER MOST MOUNTAINS AND HIGH
VALLEYS THROUGH THE EVENING...WITH FOCUS OF HEAVIER SNOW SHIFTING TO
THE EASTERN MOUNTAINS AS FLOW BECOMES WEAKLY UPSLOPE. HIGHER
PEAKS OF THE SANGRES/WETS/PIKES PEAK WILL SEE SOME MODEST (2-5 INCH)
ACCUMULATIONS THIS EVENING...WHILE VALLEYS SEE A QUICK INCH OR TWO.
PRECIP ON THE PLAINS BELOW ABOUT 6K FEET WILL START AS RAIN...WITH A
GRADUAL CHANGE OVER TO SNOW AFTER SUNSET AS COLDER AIR AT THE
SURFACE AND ALOFT SPREADS SOUTH. LATE CHANGEOVER AND WARM GROUND
WILL LIMIT ACCUMS ON THE PLAINS...THOUGH EL PASO COUNTY COULD SEE A
INCH OR TWO ONCE TEMPS DROP BELOW FREEZING AFTER SUNSET. PAST 04Z-
06Z...LIFT DECREASES OVER MOUNTAINS/WRN VALLEYS AS TROUGH DROPS
SOUTH...WITH SNOW FADING AWAY FAIRLY QUICKLY BY LATE EVENING.
EASTERN MOUNTAINS WILL LIKELY HOLD ON TO SNOW LONGER AS WEAK
UPSLOPE COMPONENT KEEPS AT LEAST SOME LIGHT SNOW GOING INTO SUN
MORNING. OVERNIGHT LOWS WILL DROP BELOW FREEZING MOST LOCATIONS AS
DRIER/COLDER AIR FILTERS SOUTH THROUGH THE NIGHT.
SUNDAY...STILL SOME LINGERING LIGHT SNOW ALONG/WEST OF I-25 IN THE
MORNING...GRADUALLY FADING TO FLURRIES IN THE AFTERNOON AS UPSLOPE
FADES AND UPPER JET SHIFTS INTO THE CENTRAL PLAINS. DESPITE SOME SUN
MANY AREAS BY AFTERNOON...CONTINUED COLD ADVECTION WILL KEEP TEMPS
FAIRLY COOL WITH MOST LOCATIONS IN THE 30S OR COLDER.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 236 PM MST SAT JAN 31 2015
MODELS CONTINUE TO HAVE DIFFERENCES IN THE MIDDLE OF THE EXTENDED
PERIOD WITH THE ECMWF HAVE BETTER ENSEMBLE SUPPORT THAN THE GFS
SOLUTION.
SUNDAY NIGHT THROUGH TUESDAY...THE UPPER PATTERN WILL FEATURE A
TROUGH MOVING OFF TO THE EAST WHILE AN UPPER RIDGE DEVELOPS ALONG
THE WEST COAST. THIS WILL PUT SOUTHERN COLORADO UNDER BROAD
NORTHWESTERLY FLOW ALOFT. SNOW WILL BE WINDING DOWN OVER THE
SOUTHERN SANGRE DE CRISTO MOUNTAINS SUNDAY EVENING WITH DRY
CONDITIONS EXPECTED ACROSS MOST OF THE REGION BY MONDAY MORNING.
THE EXCEPTION WILL BE THE CENTRAL MOUNTAINS. THE PERSISTENT
NORTHWESTERLY FLOW IS FAVORED OROGRAPHICALLY AND CONTINUOUS LIGHT
SNOW WILL PREVAIL OVER THE CENTRAL MOUNTAINS THROUGH TUESDAY
NIGHT. ACCUMULATIONS OF 3 TO 6 INCHES WITH LOCALLY HIGHER
AMOUNTS ARE POSSIBLE SUNDAY NIGHT THROUGH TUESDAY NIGHT. DRY
CONDITIONS WILL PREVAIL ACROSS THE EASTERN PLAINS. MIXING OF
NORTHWESTERLY FLOW WILL BRING WARMING TEMPERATURES TO THE LOWER
ELEVATIONS...WITH 50S FOR HIGHS ON MONDAY...AND 60S ON TUESDAY.
WEDNESDAY...MODELS CONTINUE TO STRUGGLE WITH THE NEXT WEATHER
SYSTEM EXPECTED TO REACH THE AREA ON WEDNESDAY. THE GFS IS THE
MOST AGGRESSIVE WITH THIS SHORTWAVE TROUGH...WHICH IS FORECAST TO
DROP SOUTH OUT OF THE NORTHERN ROCKIES. THE GFS DROPS A COLD
FRONT ACROSS EASTERN COLORADO AND DEVELOPS WIDESPREAD RAIN
CHANGING TO SNOW WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT BEFORE
CLEARING THE AREA BY THURSDAY MORNING. THE ECMWF...WHICH HAS
BETTER ENSEMBLE SUPPORT...IS MUCH DIFFERENT THAN THE GFS. IT TAKES
THE UPPER LEVEL SHORTWAVE TROUGH OUT OF MONTANA...AND BARELY CLIPS
NORTHEAST COLORADO AS IT TRACKS INTO THE CENTRAL PLAINS. IT ALSO
HAS A COLD FRONT BY WEDNESDAY EVENING OVER THE PLAINS...BUT DOES
NOT HAVE MUCH IN THE WAY OF PRECIPITATION ACROSS THE REGION. IT
HAS SNOW OVER THE CENTRAL MOUNTAINS...AND PERHAPS THE PALMER
DIVIDE WEDNESDAY NIGHT...BUT KEEPS THE EASTERN PLAINS DRY. FOR NOW
HAVE LOW POPS ACROSS THE PLAINS...BUT CONFIDENCE IS LOW AT THIS
TIME. TEMPERATURES ON WEDNESDAY WILL DEPEND ON FRONTAL TIMING WITH
40S TO LOWER 50S EXPECTED.
THURSDAY THROUGH SATURDAY...BROAD NORTHWESTERLY FLOW WILL
REDEVELOP ACROSS THE REGION AS HIGH PRESSURE OVER THE WEST MOVES
SLOWLY EASTWARD. LIGHT SNOW OVER THE CENTRAL MOUNTAINS IS FORECAST
TO DISSIPATE BY FRIDAY AS DRIER AIR ALOFT MOVES INTO THE AREA.
TEMPERATURES WILL ALSO REBOUND WITH 50S AND 60S BY FRIDAY AND
SATURDAY. MOZLEY
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 236 PM MST SAT JAN 31 2015
AT KALS...IFR STRATUS HAS LIFTED WITH THE ONSET OF LIGHT
SNOW...THOUGH VISIBILITY HAS GONE IFR UNDER SOME PERSISTENT SNOW
SHOWERS AS OF 22Z. IN GENERAL...EXPECT MVFR CONDITIONS THROUGH THE
EVENING WITH PERIODS OF IFR UNDER HEAVIER SNOW SHOWERS UNTIL 06Z-
08Z. DRIER AIR THEN BEGINS TO MOVE ACROSS THE VALLEY WITH CIGS
LIFTING/DISSIPATING...THOUGH SOME PATCHY GROUND FOG MAY MAKE A
BRIEF APPEARANCE AROUND SUNRISE. ON SUNDAY...VFR.
AT KCOS...EXPECT IFR/BRIEFLY LIFR CONDITIONS WITH LIGHT SNOW
AND LOW CIGS INTO THE EVENING UNTIL 04Z-05Z...THEN VIS IMPROVES AND
CIGS LIFT SLIGHTLY AFTER ABOUT 06Z...THOUGH PATCHY MVFR STRATUS MAY
LINGER THROUGH MID-MORNING SUNDAY. AFTER 16Z SUN...CIGS WILL BECOME
VFR.
AT KPUB...EXPECT A PERIOD OF MVFR CIGS AND VIS THIS EVENING AS COLD
FRONT PASSES AND -SHRA/-SHSN DEVELOP. SHOWERS END 06Z-08Z WITH
LINGERING MVFR STRATUS UNTIL MID-MORNING SUNDAY...THEN VFR.
OVER THE MOUNTAINS...MOST HIGHER TERRAIN WILL BE OBSCURED BY
CLOUDS AND SNOW SHOWERS TODAY AND TONIGHT...WITH SOME CLEARING
WORKING FROM WEST TO EAST LATE TONIGHT INTO MID MORNING SUNDAY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 8 PM MST THIS EVENING FOR COZ058-
060-061-066>068-073.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR COZ074-
075.
&&
$$
UPDATE...HODANISH
SHORT TERM...PETERSEN
LONG TERM...MOZLEY
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS ALBANY NY
630 AM EST FRI JAN 30 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE TO OUR EAST TODAY. AN ARCTIC FRONT WILL CROSS
THE REGION THIS AFTERNOON. PERIODS OF SNOW THIS MORNING FOLLOWED BY
SCATTERED TO NUMEROUS SNOW SHOWERS AND PERHAPS A SNOW SQUALL THIS
AFTERNOON. A BITTERLY COLD ARCTIC AIR MASS WILL FOLLOW USHERED IN BY
STRONG GUSTY WINDS WHICH WILL PRODUCE DANGEROUSLY COLD WIND CHILLS
TONIGHT INTO SATURDAY MORNING.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM EST...STILL SOME SNOW ON THE RADAR SCREEN LOW PRESSURE
WAS WORKING ACROSS THE UPPER HUDSON VALLEY. EVEN AS THIS STORM GOES
EAST AN UPPER LEVEL TROUGH LAGGING BEHIND...WILL KEEP SOME ASCENT
OVER THE REGION. ONLY MINOR TWEAKS TO THIS UPDATE.
THIS MID LEVEL TROUGH CONTINUES TO DIG INTO THE REGION WHICH WILL
LIKELY CONTINUE ASCENT THROUGH AT THE MORNING HOURS...LEADING TO A
POSSIBLE REGENERATION OF THE SNOW SHIELD. THE LATEST HRRR SUPPORTS
THIS IDEA.
TEMPERATURES WERE GENERALLY IN THE 25 TO 30 DEGREE RANGE.
HOWEVER...THEY WILL LIKELY NOT RISE MUCH DURING THE MORNING.
WE CONTINUED THE ADVISORY FOR THE ADIRONDACKS/MOHAWK VALLEY/LAKE
GEORGE REGION...AND SOUTHERN VERMONT WHERE 3-6 INCHES IS EXPECTED BY
MIDDAY.
AN UPPER AIR LOW WILL FORM TO OUR SOUTH MIDDAY WHILE LOW PRESSURE
MOVES TO CAPE COD. MEANWHILE AN ARCTIC AIR MASS IS POISED TO
TRANSLATE THROUGH THE REGION THIS AFTERNOON AS THE WIND PICKS UP.
THIS IS IN RESPONSE TO THE LOW DEEPENING OFF CAPE COD AS IT GETS
"CAPTURED" BY THE UPPER AIR LOW.
THERE WILL BE SCATTERED SNOW SHOWERS AROUND AND PERHAPS EVEN AN
ISOLATED SNOW SQUALL THIS AFTERNOON. HOWEVER THE BIG STORM WILL BE
STRONG GUSTY WINDS REACHING 35-40 MPH MOST PLACES WHICH WILL BEGIN
TO DRIVE TEMPERATURES DOWNWARD. AFTER CRESTING MIDDAY...THEY WILL
DROP BACK THROUGH THE 20S DURING THE AFTERNOON/TEENS ADIRONDACKS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
WIND CHILL WARNINGS FOR NORTHERN HERKIMER COUNTY AND HAMILTON
COUNTIES. WIND CHILL ADVISORIES FOR THE REMAINDER OF EASTERN NEW
YORK AND ADJACENT NEW ENGLAND. ALL TIMES ARE FROM 6 PM THROUGH 11AM
SATURDAY.
TONIGHT...THERE STILL COULD SOME UPSLOPE SNOW SHOWERS FOR AWHILE
ACROSS THE SOUTHERN GREENS OF VERMONT. OTHERWISE...THE SKY SHOULD
EVENTUALLY CLEAR BUT THE WIND WILL CONTINUE AND TEMPERATURES WILL
DIVE TO NEAR ZERO IN THE CAPITAL REGION...5 TO 15 BELOW ZERO ACROSS
OUR NORTHERN ZONES...SINGLE NUMBERS SOUTH OF THE CAPITAL REGION.
WIND GUSTS WILL AGAIN BE IN THE 35-40 MPH RANGE AT TIMES.
THE COMBINATION OF THE WIND AND VERY COLD TEMPERATURES HAS PROMPTED
US TO CONTINUE WIND CHILL ADVISORIES EVERYWHERE TONIGHT EXCEPT WIND
CHILL WARNINGS NORTHERN HERKIMER AND HAMILTON COUNTIES.
THE WIND WILL BE RESULT OF A DEEP LOW PRESSURE DEEPENING IN THE GULF
OF MAINE. THE LOW WILL ONLY SLOW FURTHER MOVE AWAY ON SATURDAY.
SATURDAY WILL BE A MAINLY SUNNY BUT WINDY AND BITTERLY COLD DAY. THE
WIND WILL ABATE A LITTLE DURING THE AFTERNOON...BUT TEMPERATURES
ONLY RECOVER TO 20 AT BEST IN THE MID HUDSON VALLEY...TEENS FURTHER
NORTH IN AND AROUND THE CAPITAL REGION...ONLY SINGLE NUMBERS OVER
OUR NORTHERN AREAS...INCLUDING MOST OF SOUTHERN VERMONT.
SATURDAY NIGHT...BELIEVE IT OR NOT...YET ANOTHER ARCTIC FRONT A WEAK
CLIPPER WILL WORK ACROSS NEW YORK STATE. ANY SENSIBLE WEATHER SHOULD
BE MAINLY CONFINED TO AREAS NORTH OF THE CAPITAL REGION WHERE CLOUDS
AND THE THREAT OF SNOW SHOWERS WILL EXIT. THE APPROACHING FRONT
WILL SERVE TO PREVENT TEMPERATURES FROM FALLING QUITE AS LOW AS THEY
WOULD HAVE OTHERWISE. STILL LOOK FOR TEMPERATURES AROUND ZERO TO
THEN NORTH OF THE CAPITAL REGION...SINGLE NUMBERS TO AROUND 10
CAPITAL REGION AND POINTS SOUTH.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
NEARLY EXCELLENT SYNOPTIC AGREEMENT AMONG THE LONG TERM FORECAST
GUIDANCE THIS MORNING AS THE FORECAST TRENDS FOR THE MONDAY EVENT
HAVE TRENDED NORTHWARD ONCE AGAIN.
FOR SUNDAY...FEBRUARY 1ST...ARCTIC FRONTAL BOUNDARY THAT WE HAVE
BEEN DISCUSSING THE PAST SEVERAL DAYS IS STILL PROGGED TO SLIDE
SOUTHWARD AND EITHER STALL OR BECOME ILL-DEFINED THROUGH THE DAY.
PLACEMENT OF THIS FRONT DOES DIFFER AMONG THE GUIDANCE WITH RECENT
TENDENCIES PLACING IT ALONG OR JUST NORTH OF THE I80 CORRIDOR. THEN
WE QUICKLY SHIFT OUR ATTENTION TO THE APPROACHING OHIO VALLEY SYSTEM.
THE STRONG PC ANOMALY WAS ASHORE ALONG BRITISH COLUMBIA AS MOISTURE
CONTINUES TO ADVECT INTO THE FOUR CORNERS REGION PER THE H2O VAPOR
ANALYSIS THIS FRIDAY MORNING. THE COMBINATION OF THESE FEATURES ARE
FORECAST TO MERGE ACROSS THE CENTRAL PLAINS/MID-MISSISSIPPI RIVER
VALLEY SUNDAY NIGHT AND SPAWN SURFACE CYCLOGENESIS BETWEEN I70-I80.
THE UPPER TROUGH AMPLIFIES OVER THE OHIO VALLEY AS THE SURFACE LOW
BEGINS TO DEEPEN ACROSS THE MID ATLANTIC MONDAY MORNING. THE QPF
FIELDS AND 2D-FGEN FIELDS LINE UP MAINLY SOUTH OF I90 ON MONDAY
WHERE AN ACCUMULATING SNOW EVENT IS EXPECTED. ENSEMBLE DATA AND
PLUMES NOW SUGGEST MORE THAN HALF THE MEMBERS ARE FURTHER NORTH THAN
PREVIOUS RUNS. IN FACT...THE LATEST 30/06Z NAM12 IS FURTHER NORTH
AS WELL WITH MODERATE QPF VALUES. WE WILL REINTRODUCE THIS
POTENTIAL MILLER TYPE B EVENT INTO THE HWO AT THIS TIME. THERMAL
PROFILES ACROSS THE REGION ARE NOT ONLY COLD BUT WILL OFFER A
CHALLENGE WITH RESPECT TO LIQUID TO SNOW RATIOS. THE HIGHER RATIOS
WILL LIKELY BE ALONG AND NORTH OF I90 WHERE VALUES COULD BE
APPROACHING 20:1. STILL PLENTY OF TIME AS THIS PV ANOMALY WILL BE
ENTERING THE UPPER AIR NETWORK WHICH SHOULD...HOPEFULLY...RESOLVE
AND NARROW THE SOLUTIONS. AS AN FYI...EVALUATING THE LATEST CIPS
GUIDANCE...MANY OF THE MATCHES DO BRING AN ACCUMULATING SNOW TO THE
REGION.
THIS WAVE DEPARTS OFF THE COAST MONDAY EVENING AS 1030MB SURFACE
HIGH SLIDES INTO THE OHIO VALLEY AND EXTENDS ITS INFLUENCE INTO THE
NORTHEAST. AS H850 TEMPS ARE EXPECTED TO FALL BELOW -20C...AND
POTENTIAL FOR A FRESH SNOW COVER...WILL PROVIDE THE OPPORTUNITY FOR
A VERY COLD NIGHT ACROSS THE REGION. WOULD NOT BE SURPRISED IF SOME
LOCATIONS ATTEMPT TO APPROACH RECORD LOWS.
THE HIGH SLIDES ACROSS THE MID ATLANTIC REGION THROUGH TUESDAY WHICH
SHOULD KEEP OUR WEATHER PATTERN TRANQUIL YET CHILLY. NEXT ARCTIC
IMPULSE IS FORECAST TO MOVE SOUTHEAST TOWARD THE GREAT LAKES REGION
FOR THE MID WEEK PERIOD WITH ANOTHER CHANCE FOR SNOW SHOWERS LATER
WEDNESDAY INTO THURSDAY. THE TIMING OF THIS ARCTIC FRONTAL AND
TRACK OF A SOUTHERN STREAM IMPULSE COULD MAKE FOR AN INTERESTING
COASTAL DEVELOPMENT THROUGH THURSDAY. WHILE MAJORITY OF THE
ENSEMBLE MEMBERS KEEP THIS WAVE OFFSHORE...THERE ARE A FEW OUTLYING
MEMBERS THAT KEEP THIS WAVE CLOSER TO THE COASTLINE.
TEMPERATURES THROUGH THE PERIOD WILL BE BELOW NORMAL.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
PERIODS/OCCASIONAL BURSTS OF SNOW WILL CONTINUE TO MOVE ACROSS THE
REGION THIS MORNING. DUE TO THIS...VISIBILITIES WILL BE A CHALLENGE
TO FORECAST AS WE WILL OBSERVE MVFR TO IFR IN SHORT/BRIEF BURSTS.
AT THE MINIMUM...CIGS WILL BE SOLIDLY IN MVFR AT ALL TAF SITES
THROUGH AT LEAST THIS MORNING.
TRENDS IN THE SHORT TERM MODELS CONTINUE TO HINT AT BAND OF SNOW
MOVING THROUGH THE HUDSON RIVER VALLEY THIS MORNING WHERE THE BEST
POTENTIAL FOR IFR CONDITIONS AT ALL TAF LOCATIONS.
THEREAFTER...DURING THE LATE MORNING HOURS...CONDITIONS WILL IMPROVE
WITH RESPECT TO DIMINISHING TRENDS IN THE SNOW AND LOW CIGS. THEN A
WIND SHIFT WILL RESULT IN AN INCREASE OF MAGNITUDES WHERE SOME
BLOWING SNOW COULD RESULT FOR THE REMAINDER OF THE DAY.
WINDS THIS MORNING WILL GENERALLY BE SOUTHERLY AROUND 10KTS WITH
SOME GUSTS. WINDS WILL QUICKLY SHIFTS TO THE WEST THEN NORTHWEST
AROUND NOON WITH 10-15KTS WITH GUSTS AT OR ABOVE 20KTS.
OUTLOOK...
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDRO PROBLEMS ARE EXPECTED THROUGH THE NEXT 5 DAYS.
SNOW WILL TAPER TO SNOW SHOWERS BY AFTERNOON. SNOWFALL WILL RANGE
FROM 1-3 INCHES FROM THE CAPITAL REGION SOUTHWARD...3-6 INCHES
FURTHER NORTH.
ADDITIONAL SNOW SHOWERS ARE POSSIBLE THIS AFTERNOON INTO EVENING
WITH GENERALLY MINOR ADDITIONAL ACCUMULATIONS.
THERE IS ALSO A LOW TO MODERATE CHANCE OF SNOW SUNDAY NIGHT INTO
MONDAY.
ICE WILL CONTINUE TO THICKEN ON RIVERS...STREAMS...CREEKS...LAKES
AND OTHER BODIES OF WATER.
THE EAGLE BRIDGE GAGE ON THE HOOSIC RIVER CONTINUES TO BE HAMPERED
BY ICE EFFECTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR CTZ001-013.
NY...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ038>043-047>054-058>061-063>066-082>084.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ032-033-038>043-082>084.
WIND CHILL WARNING FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ032-033.
MA...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR MAZ001-025.
VT...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR VTZ013>015.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
HYDROLOGY...HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
628 AM EST FRI JAN 30 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE TO OUR EAST TODAY. AN ARCTIC FRONT WILL CROSS
THE REGION THIS AFTERNOON. PERIODS OF SNOW THIS MORNING FOLLOWED BY
SCATTERED TO NUMEROUS SNOW SHOWERS AND PERHAPS A SNOW SQUALL THIS
AFTERNOON. A BITTERLY COLD ARCTIC AIR MASS WILL FOLLOW USHERED IN BY
STRONG GUSTY WINDS WHICH WILL PRODUCE DANGEROUSLY COLD WIND CHILLS
TONIGHT INTO SATURDAY MORNING.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 445 AM EST...A SMATTERING OF SNOW THIS MORNING...CONTAINING
SOME BANDLETS OF MODERATE SNOW...WITH OTHERWISE LIGHT SNOW FALLING.
THERE APPEARS TO BE A BACK EDGE TO THE SNOW WORKING TO THE WEST OF
THE HUDSON VALLEY. HOWEVER...A MID LEVEL TROUGH CONTINUES TO DIG
INTO THE REGION WHICH WILL LIKELY CONTINUE ASCENT THROUGH AT THE
MORNING HOURS...LEADING TO A POSSIBLE REGENERATION OF THE SNOW
SHIELD. THE LATEST HRRR SUPPORTS THIS IDEA.
TEMPERATURES WERE GENERALLY IN THE 25 TO 30 DEGREE RANGE.
HOWEVER...THEY WILL LIKELY NOT RISE MUCH DURING THE MORNING.
WE DID CANCEL A PORTION OF THE WINTER WEATHER ADVISORY WHERE IT
APPEARS ONLY 1-3 INCHES OF SNOW WILL ACCUMULATE...BASICALLY FROM THE
CAPITAL REGION SOUTHWARD AND EASTWARD.
WE CONTINUED THE ADVISORY FOR THE ADIRONDACKS/MOHAWK VALLEY/LAKE
GEORGE REGION...AND SOUTHERN VERMONT WHERE 3-6 INCHES IS EXPECTED BY
MIDDAY.
AN UPPER AIR LOW WILL FORM TO OUR SOUTH MIDDAY WHILE LOW PRESSURE
MOVES TO CAPE COD. MEANWHILE AN ARCTIC AIR MASS IS POISED TO
TRANSLATE THROUGH THE REGION THIS AFTERNOON AS THE WIND PICKS UP.
THIS IS IN RESPONSE TO THE LOW DEEPENING OFF CAPE COD AS IT GETS
"CAPTURED" BY THE UPPER AIR LOW.
THERE WILL BE SCATTERED SNOW SHOWERS AROUND AND PERHAPS EVEN AN
ISOLATED SNOW SQUALL THIS AFTERNOON. HOWEVER THE BIG STORM WILL BE
STRONG GUSTY WINDS REACHING 35-40 MPH MOST PLACES WHICH WILL BEGIN
TO DRIVE TEMPERATURES DOWNWARD. AFTER CRESTING MIDDAY...THEY WILL
DROP BACK THROUGH THE 20S DURING THE AFTERNOON/TEENS ADIRONDACKS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
WIND CHILL WARNINGS FOR NORTHERN HERKIMER COUNTY AND HAMILTON
COUNTIES. WIND CHILL ADVISORIES FOR THE REMAINDER OF EASTERN NEW
YORK AND ADJACENT NEW ENGLAND. ALL TIMES ARE FROM 6 PM THROUGH 11AM
SATURDAY.
TONIGHT...THERE STILL COULD SOME UPSLOPE SNOW SHOWERS FOR AWHILE
ACROSS THE SOUTHERN GREENS OF VERMONT. OTHERWISE...THE SKY SHOULD
EVENTUALLY CLEAR BUT THE WIND WILL CONTINUE AND TEMPERATURES WILL
DIVE TO NEAR ZERO IN THE CAPITAL REGION...5 TO 15 BELOW ZERO ACROSS
OUR NORTHERN ZONES...SINGLE NUMBERS SOUTH OF THE CAPITAL REGION.
WIND GUSTS WILL AGAIN BE IN THE 35-40 MPH RANGE AT TIMES.
THE COMBINATION OF THE WIND AND VERY COLD TEMPERATURES HAS PROMPTED
US TO CONTINUE WIND CHILL ADVISORIES EVERYWHERE TONIGHT EXCEPT WIND
CHILL WARNINGS NORTHERN HERKIMER AND HAMILTON COUNTIES.
THE WIND WILL BE RESULT OF A DEEP LOW PRESSURE DEEPENING IN THE GULF
OF MAINE. THE LOW WILL ONLY SLOW FURTHER MOVE AWAY ON SATURDAY.
SATURDAY WILL BE A MAINLY SUNNY BUT WINDY AND BITTERLY COLD DAY. THE
WIND WILL ABATE A LITTLE DURING THE AFTERNOON...BUT TEMPERATURES
ONLY RECOVER TO 20 AT BEST IN THE MID HUDSON VALLEY...TEENS FURTHER
NORTH IN AND AROUND THE CAPITAL REGION...ONLY SINGLE NUMBERS OVER
OUR NORTHERN AREAS...INCLUDING MOST OF SOUTHERN VERMONT.
SATURDAY NIGHT...BELIEVE IT OR NOT...YET ANOTHER ARCTIC FRONT A WEAK
CLIPPER WILL WORK ACROSS NEW YORK STATE. ANY SENSIBLE WEATHER SHOULD
BE MAINLY CONFINED TO AREAS NORTH OF THE CAPITAL REGION WHERE CLOUDS
AND THE THREAT OF SNOW SHOWERS WILL EXIT. THE APPROACHING FRONT
WILL SERVE TO PREVENT TEMPERATURES FROM FALLING QUITE AS LOW AS THEY
WOULD HAVE OTHERWISE. STILL LOOK FOR TEMPERATURES AROUND ZERO TO
THEN NORTH OF THE CAPITAL REGION...SINGLE NUMBERS TO AROUND 10
CAPITAL REGION AND POINTS SOUTH.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
NEARLY EXCELLENT SYNOPTIC AGREEMENT AMONG THE LONG TERM FORECAST
GUIDANCE THIS MORNING AS THE FORECAST TRENDS FOR THE MONDAY EVENT
HAVE TRENDED NORTHWARD ONCE AGAIN.
FOR SUNDAY...FEBRUARY 1ST...ARCTIC FRONTAL BOUNDARY THAT WE HAVE
BEEN DISCUSSING THE PAST SEVERAL DAYS IS STILL PROGGED TO SLIDE
SOUTHWARD AND EITHER STALL OR BECOME ILL-DEFINED THROUGH THE DAY.
PLACEMENT OF THIS FRONT DOES DIFFER AMONG THE GUIDANCE WITH RECENT
TENDENCIES PLACING IT ALONG OR JUST NORTH OF THE I80 CORRIDOR. THEN
WE QUICKLY SHIFT OUR ATTENTION TO THE APPROACHING OHIO VALLEY SYSTEM.
THE STRONG PC ANOMALY WAS ASHORE ALONG BRITISH COLUMBIA AS MOISTURE
CONTINUES TO ADVECT INTO THE FOUR CORNERS REGION PER THE H2O VAPOR
ANALYSIS THIS FRIDAY MORNING. THE COMBINATION OF THESE FEATURES ARE
FORECAST TO MERGE ACROSS THE CENTRAL PLAINS/MID-MISSISSIPPI RIVER
VALLEY SUNDAY NIGHT AND SPAWN SURFACE CYCLOGENESIS BETWEEN I70-I80.
THE UPPER TROUGH AMPLIFIES OVER THE OHIO VALLEY AS THE SURFACE LOW
BEGINS TO DEEPEN ACROSS THE MID ATLANTIC MONDAY MORNING. THE QPF
FIELDS AND 2D-FGEN FIELDS LINE UP MAINLY SOUTH OF I90 ON MONDAY
WHERE AN ACCUMULATING SNOW EVENT IS EXPECTED. ENSEMBLE DATA AND
PLUMES NOW SUGGEST MORE THAN HALF THE MEMBERS ARE FURTHER NORTH THAN
PREVIOUS RUNS. IN FACT...THE LATEST 30/06Z NAM12 IS FURTHER NORTH
AS WELL WITH MODERATE QPF VALUES. WE WILL REINTRODUCE THIS
POTENTIAL MILLER TYPE B EVENT INTO THE HWO AT THIS TIME. THERMAL
PROFILES ACROSS THE REGION ARE NOT ONLY COLD BUT WILL OFFER A
CHALLENGE WITH RESPECT TO LIQUID TO SNOW RATIOS. THE HIGHER RATIOS
WILL LIKELY BE ALONG AND NORTH OF I90 WHERE VALUES COULD BE
APPROACHING 20:1. STILL PLENTY OF TIME AS THIS PV ANOMALY WILL BE
ENTERING THE UPPER AIR NETWORK WHICH SHOULD...HOPEFULLY...RESOLVE
AND NARROW THE SOLUTIONS. AS AN FYI...EVALUATING THE LATEST CIPS
GUIDANCE...MANY OF THE MATCHES DO BRING AN ACCUMULATING SNOW TO THE
REGION.
THIS WAVE DEPARTS OFF THE COAST MONDAY EVENING AS 1030MB SURFACE
HIGH SLIDES INTO THE OHIO VALLEY AND EXTENDS ITS INFLUENCE INTO THE
NORTHEAST. AS H850 TEMPS ARE EXPECTED TO FALL BELOW -20C...AND
POTENTIAL FOR A FRESH SNOW COVER...WILL PROVIDE THE OPPORTUNITY FOR
A VERY COLD NIGHT ACROSS THE REGION. WOULD NOT BE SURPRISED IF SOME
LOCATIONS ATTEMPT TO APPROACH RECORD LOWS.
THE HIGH SLIDES ACROSS THE MID ATLANTIC REGION THROUGH TUESDAY WHICH
SHOULD KEEP OUR WEATHER PATTERN TRANQUIL YET CHILLY. NEXT ARCTIC
IMPULSE IS FORECAST TO MOVE SOUTHEAST TOWARD THE GREAT LAKES REGION
FOR THE MID WEEK PERIOD WITH ANOTHER CHANCE FOR SNOW SHOWERS LATER
WEDNESDAY INTO THURSDAY. THE TIMING OF THIS ARCTIC FRONTAL AND
TRACK OF A SOUTHERN STREAM IMPULSE COULD MAKE FOR AN INTERESTING
COASTAL DEVELOPMENT THROUGH THURSDAY. WHILE MAJORITY OF THE
ENSEMBLE MEMBERS KEEP THIS WAVE OFFSHORE...THERE ARE A FEW OUTLYING
MEMBERS THAT KEEP THIS WAVE CLOSER TO THE COASTLINE.
TEMPERATURES THROUGH THE PERIOD WILL BE BELOW NORMAL.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
PERIODS/OCCASIONAL BURSTS OF SNOW WILL CONTINUE TO MOVE ACROSS THE
REGION. DUE TO THIS...VISIBILITIES WILL BE A CHALLENGE TO FORECAST
AS WE WILL OBSERVE MVFR TO IFR IN SHORT/BRIEF BURSTS. AT THE
MINIMUM...CIGS WILL BE SOLIDLY IN MVFR AT ALL TAF SITES THE
REMAINDER OF THE OVERNIGHT PERIOD.
TRENDS IN THE SHORT TERM MODELS HINT A BAND OF SNOW MOVING THROUGH
THE HUDSON RIVER VALLEY AROUND SUNRISE WHERE THE BEST POTENTIAL FOR
IFR CONDITIONS AT ALL TAF LOCATIONS. THEREAFTER...DURING THE MID
MORNING HOURS...CONDITIONS WILL IMPROVE WITH RESPECT TO DIMINISHING
TRENDS IN THE SNOW AND LOW CIGS. THEN A WIND SHIFT WILL RESULT IN
AN INCREASE OF MAGNITUDES WHERE SOME BLOWING SNOW COULD RESULT FOR
THE REMAINDER OF THE DAY.
WINDS OVERNIGHT WILL GENERALLY BE SOUTHERLY AROUND 10KTS WITH SOME
GUSTS IN KALB. WINDS WILL QUICKLY SHIFTS TO THE WEST THEN NORTHWEST
FRIDAY MORNING WITH 10-15KTS WITH GUSTS AT OR ABOVE 20KTS.
OUTLOOK...
SATURDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY SLIGHT CHANCE OF SHSN.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDRO PROBLEMS ARE EXPECTED THROUGH THE NEXT 5 DAYS.
SNOW WILL TAPER TO SNOW SHOWERS BY AFTERNOON. SNOWFALL WILL RANGE
FROM 1-3 INCHES FROM THE CAPITAL REGION SOUTHWARD...3-6 INCHES
FURTHER NORTH.
ADDITIONAL SNOW SHOWERS ARE POSSIBLE THIS AFTERNOON INTO EVENING
WITH GENERALLY MINOR ADDITIONAL ACCUMULATIONS.
THERE IS ALSO A LOW TO MODERATE CHANCE OF SNOW SUNDAY NIGHT INTO
MONDAY.
ICE WILL CONTINUE TO THICKEN ON RIVERS...STREAMS...CREEKS...LAKES
AND OTHER BODIES OF WATER.
THE EAGLE BRIDGE GAGE ON THE HOOSIC RIVER CONTINUES TO BE HAMPERED
BY ICE EFFECTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR CTZ001-013.
NY...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ038>043-047>054-058>061-063>066-082>084.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ032-033-038>043-082>084.
WIND CHILL WARNING FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ032-033.
MA...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR MAZ001-025.
VT...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR VTZ013>015.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
HYDROLOGY...HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
455 AM EST FRI JAN 30 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE TO OUR EAST TODAY. AN ARCTIC FRONT WILL CROSS
THE REGION THIS AFTERNOON. PERIODS OF SNOW THIS MORNING FOLLOWED BY
SCATTERED TO NUMEROUS SNOW SHOWERS AND PERHAPS A SNOW SQUALL THIS
AFTERNOON. A BITTERLY COLD ARCTIC AIR MASS WILL FOLLOW USHERED IN BY
STRONG GUSTY WINDS WHICH WILL PRODUCE DANGEROUSLY COLD WIND CHILLS
TONIGHT INTO SATURDAY MORNING.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 445 AM EST...A SMATTERING OF SNOW THIS MORNING...CONTAINING
SOME BANDLETS OF MODERATE SNOW...WITH OTHERWISE LIGHT SNOW FALLING.
THERE APPEARS TO BE A BACK EDGE TO THE SNOW WORKING TO THE WEST OF
THE HUDSON VALLEY. HOWEVER...A MID LEVEL TROUGH CONTINUES TO DIG
INTO THE REGION WHICH WILL LIKELY CONTINUE ASCENT THROUGH AT THE
MORNING HOURS...LEADING TO A POSSIBLE REGENERATION OF THE SNOW
SHIELD. THE LATEST HRRR SUPPORTS THIS IDEA.
TEMPERATURES WERE GENERALLY IN THE 25 TO 30 DEGREE RANGE.
HOWEVER...THEY WILL LIKELY NOT RISE MUCH DURING THE MORNING.
WE DID CANCEL A PORTION OF THE WINTER WEATHER ADVISORY WHERE IT
APPEARS ONLY 1-3 INCHES OF SNOW WILL ACCUMULATE...BASICALLY FROM THE
CAPITAL REGION SOUTHWARD AND EASTWARD.
WE CONTINUED THE ADVISORY FOR THE ADIRONDACKS/MOHAWK VALLEY/LAKE
GEORGE REGION...AND SOUTHERN VERMONT WHERE 3-6 INCHES IS EXPECTED BY
MIDDAY.
AN UPPER AIR LOW WILL FORM TO OUR SOUTH MIDDAY WHILE LOW PRESSURE
MOVES TO CAPE COD. MEANWHILE AN ARCTIC AIR MASS IS POISED TO
TRANSLATE THROUGH THE REGION THIS AFTERNOON AS THE WIND PICKS UP.
THIS IS IN RESPONSE TO THE LOW DEEPENING OFF CAPE COD AS IT GETS
"CAPTURED" BY THE UPPER AIR LOW.
THERE WILL BE SCATTERED SNOW SHOWERS AROUND AND PERHAPS EVEN AN
ISOLATED SNOW SQUALL THIS AFTERNOON. HOWEVER THE BIG STORM WILL BE
STRONG GUSTY WINDS REACHING 35-40 MPH MOST PLACES WHICH WILL BEGIN
TO DRIVE TEMPERATURES DOWNWARD. AFTER CRESTING MIDDAY...THEY WILL
DROP BACK THROUGH THE 20S DURING THE AFTERNOON/TEENS ADIRONDACKS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
WIND CHILL WARNINGS FOR NORTHERN HERKIMER COUNTY AND HAMILTON
COUNTIES. WIND CHILL ADVISORIES FOR THE REMAINDER OF EASTERN NEW
YORK AND ADJACENT NEW ENGLAND. ALL TIMES ARE FROM 6 PM THROUGH 11AM
SATURDAY.
TONIGHT...THERE STILL COULD SOME UPSLOPE SNOW SHOWERS FOR AWHILE
ACROSS THE SOUTHERN GREENS OF VERMONT. OTHERWISE...THE SKY SHOULD
EVENTUALLY CLEAR BUT THE WIND WILL CONTINUE AND TEMPERATURES WILL
DIVE TO NEAR ZERO IN THE CAPITAL REGION...5 TO 15 BELOW ZERO ACROSS
OUR NORTHERN ZONES...SINGLE NUMBERS SOUTH OF THE CAPITAL REGION.
WIND GUSTS WILL AGAIN BE IN THE 35-40 MPH RANGE AT TIMES.
THE COMBINATION OF THE WIND AND VERY COLD TEMPERATURES HAS PROMPTED
US TO CONTINUE WIND CHILL ADVISORIES EVERYWHERE TONIGHT EXCEPT WIND
CHILL WARNINGS NORTHERN HERKIMER AND HAMILTON COUNTIES.
THE WIND WILL BE RESULT OF A DEEP LOW PRESSURE DEEPENING IN THE GULF
OF MAINE. THE LOW WILL ONLY SLOW FURTHER MOVE AWAY ON SATURDAY.
SATURDAY WILL BE A MAINLY SUNNY BUT WINDY AND BITTERLY COLD DAY. THE
WIND WILL ABATE A LITTLE DURING THE AFTERNOON...BUT TEMPERATURES
ONLY RECOVER TO 20 AT BEST IN THE MID HUDSON VALLEY...TEENS FURTHER
NORTH IN AND AROUND THE CAPITAL REGION...ONLY SINGLE NUMBERS OVER
OUR NORTHERN AREAS...INCLUDING MOST OF SOUTHERN VERMONT.
SATURDAY NIGHT...BELIEVE IT OR NOT...YET ANOTHER ARCTIC FRONT A WEAK
CLIPPER WILL WORK ACROSS NEW YORK STATE. ANY SENSIBLE WEATHER SHOULD
BE MAINLY CONFINED TO AREAS NORTH OF THE CAPITAL REGION WHERE CLOUDS
AND THE THREAT OF SNOW SHOWERS WILL EXIT. THE APPROACHING FRONT
WILL SERVE TO PREVENT TEMPERATURES FROM FALLING QUITE AS LOW AS THEY
WOULD HAVE OTHERWISE. STILL LOOK FOR TEMPERATURES AROUND ZERO TO
THEN NORTH OF THE CAPITAL REGION...SINGLE NUMBERS TO AROUND 10
CAPITAL REGION AND POINTS SOUTH.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
NEARLY EXCELLENT SYNOPTIC AGREEMENT AMONG THE LONG TERM FORECAST
GUIDANCE THIS MORNING AS THE FORECAST TRENDS FOR THE MONDAY EVENT
HAVE TRENDED NORTHWARD ONCE AGAIN.
FOR SUNDAY...FEBRUARY 1ST...ARCTIC FRONTAL BOUNDARY THAT WE HAVE
BEEN DISCUSSING THE PAST SEVERAL DAYS IS STILL PROGGED TO SLIDE
SOUTHWARD AND EITHER STALL OR BECOME ILL-DEFINED THROUGH THE DAY.
PLACEMENT OF THIS FRONT DOES DIFFER AMONG THE GUIDANCE WITH RECENT
TENDENCIES PLACING IT ALONG OR JUST NORTH OF THE I80 CORRIDOR. THEN
WE QUICKLY SHIFT OUR ATTENTION TO THE APPROACHING OHIO VALLEY SYSTEM.
THE STRONG PC ANOMALY WAS ASHORE ALONG BRITISH COLUMBIA AS MOISTURE
CONTINUES TO ADVECT INTO THE FOUR CORNERS REGION PER THE H2O VAPOR
ANALYSIS THIS FRIDAY MORNING. THE COMBINATION OF THESE FEATURES ARE
FORECAST TO MERGE ACROSS THE CENTRAL PLAINS/MID-MISSISSIPPI RIVER
VALLEY SUNDAY NIGHT AND SPAWN SURFACE CYCLOGENESIS BETWEEN I70-I80.
THE UPPER TROUGH AMPLIFIES OVER THE OHIO VALLEY AS THE SURFACE LOW
BEGINS TO DEEPEN ACROSS THE MID ATLANTIC MONDAY MORNING. THE QPF
FIELDS AND 2D-FGEN FIELDS LINE UP MAINLY SOUTH OF I90 ON MONDAY
WHERE AN ACCUMULATING SNOW EVENT IS EXPECTED. ENSEMBLE DATA AND
PLUMES NOW SUGGEST MORE THAN HALF THE MEMBERS ARE FURTHER NORTH THAN
PREVIOUS RUNS. IN FACT...THE LATEST 30/06Z NAM12 IS FURTHER NORTH
AS WELL WITH MODERATE QPF VALUES. WE WILL REINTRODUCE THIS
POTENTIAL MILLER TYPE B EVENT INTO THE HWO AT THIS TIME. THERMAL
PROFILES ACROSS THE REGION ARE NOT ONLY COLD BUT WILL OFFER A
CHALLENGE WITH RESPECT TO LIQUID TO SNOW RATIOS. THE HIGHER RATIOS
WILL LIKELY BE ALONG AND NORTH OF I90 WHERE VALUES COULD BE
APPROACHING 20:1. STILL PLENTY OF TIME AS THIS PV ANOMALY WILL BE
ENTERING THE UPPER AIR NETWORK WHICH SHOULD...HOPEFULLY...RESOLVE
AND NARROW THE SOLUTIONS. AS AN FYI...EVALUATING THE LATEST CIPS
GUIDANCE...MANY OF THE MATCHES DO BRING AN ACCUMULATING SNOW TO THE
REGION.
THIS WAVE DEPARTS OFF THE COAST MONDAY EVENING AS 1030MB SURFACE
HIGH SLIDES INTO THE OHIO VALLEY AND EXTENDS ITS INFLUENCE INTO THE
NORTHEAST. AS H850 TEMPS ARE EXPECTED TO FALL BELOW -20C...AND
POTENTIAL FOR A FRESH SNOW COVER...WILL PROVIDE THE OPPORTUNITY FOR
A VERY COLD NIGHT ACROSS THE REGION. WOULD NOT BE SURPRISED IF SOME
LOCATIONS ATTEMPT TO APPROACH RECORD LOWS.
THE HIGH SLIDES ACROSS THE MID ATLANTIC REGION THROUGH TUESDAY WHICH
SHOULD KEEP OUR WEATHER PATTERN TRANQUIL YET CHILLY. NEXT ARCTIC
IMPULSE IS FORECAST TO MOVE SOUTHEAST TOWARD THE GREAT LAKES REGION
FOR THE MID WEEK PERIOD WITH ANOTHER CHANCE FOR SNOW SHOWERS LATER
WEDNESDAY INTO THURSDAY. THE TIMING OF THIS ARCTIC FRONTAL AND
TRACK OF A SOUTHERN STREAM IMPULSE COULD MAKE FOR AN INTERESTING
COASTAL DEVELOPMENT THROUGH THURSDAY. WHILE MAJORITY OF THE
ENSEMBLE MEMBERS KEEP THIS WAVE OFFSHORE...THERE ARE A FEW OUTLYING
MEMBERS THAT KEEP THIS WAVE CLOSER TO THE COASTLINE.
TEMPERATURES THROUGH THE PERIOD WILL BE BELOW NORMAL.
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
PERIODS/OCCASIONAL BURSTS OF SNOW WILL CONTINUE TO MOVE ACROSS THE
REGION. DUE TO THIS...VISIBILITIES WILL BE A CHALLENGE TO FORECAST
AS WE WILL OBSERVE MVFR TO IFR IN SHORT/BRIEF BURSTS. AT THE
MINIMUM...CIGS WILL BE SOLIDLY IN MVFR AT ALL TAF SITES THE
REMAINDER OF THE OVERNIGHT PERIOD.
TRENDS IN THE SHORT TERM MODELS HINT A BAND OF SNOW MOVING THROUGH
THE HUDSON RIVER VALLEY AROUND SUNRISE WHERE THE BEST POTENTIAL FOR
IFR CONDITIONS AT ALL TAF LOCATIONS. THEREAFTER...DURING THE MID
MORNING HOURS...CONDITIONS WILL IMPROVE WITH RESPECT TO DIMINISHING
TRENDS IN THE SNOW AND LOW CIGS. THEN A WIND SHIFT WILL RESULT IN
AN INCREASE OF MAGNITUDES WHERE SOME BLOWING SNOW COULD RESULT FOR
THE REMAINDER OF THE DAY.
WINDS OVERNIGHT WILL GENERALLY BE SOUTHERLY AROUND 10KTS WITH SOME
GUSTS IN KALB. WINDS WILL QUICKLY SHIFTS TO THE WEST THEN NORTHWEST
FRIDAY MORNING WITH 10-15KTS WITH GUSTS AT OR ABOVE 20KTS.
OUTLOOK...
SATURDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY SLIGHT CHANCE OF SHSN.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDRO PROBLEMS ARE EXPECTED THROUGH THE NEXT 5 DAYS.
SNOW WILL TAPER TO SNOW SHOWERS BY AFTERNOON. SNOWFALL WILL RANGE
FROM 1-3 INCHES FROM THE CAPITAL REGION SOUTHWARD...3-6 INCHES
FURTHER NORTH.
ADDITIONAL SNOW SHOWERS ARE POSSIBLE THIS AFTERNOON INTO EVENING
WITH GENERALLY MINOR ADDITIONAL ACCUMULATIONS.
THERE IS ALSO A LOW TO MODERATE CHANCE OF SNOW SUNDAY NIGHT INTO
MONDAY.
ICE WILL CONTINUE TO THICKEN ON RIVERS...STREAMS...CREEKS...LAKES
AND OTHER BODIES OF WATER.
THE EAGLE BRIDGE GAGE ON THE HOOSIC RIVER CONTINUES TO BE HAMPERED
BY ICE EFFECTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR CTZ001-013.
NY...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ038>043-047>054-058>061-063>066-082>084.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NYZ032-033-038>043-082>084.
WIND CHILL WARNING FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ032-033.
MA...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR MAZ001-025.
VT...WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM EST
SATURDAY FOR VTZ013>015.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
VTZ013>015.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
HYDROLOGY...HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1244 AM EST FRI JAN 30 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE ACROSS NORTHERN NEW YORK
TONIGHT...AND THEN MOVE EAST OF NEW ENGLAND BY TOMORROW AFTERNOON
BRINGING A LIGHT TO MODERATE SNOWFALL TO THE REGION. AN ARCTIC
FRONT WILL CROSS THE REGION TOMORROW AFTERNOON INTO TOMORROW NIGHT
WITH A SURGE OF ARCTIC AIR...AND BITTERLY COLD WIND CHILLS. FRIGID
TEMPERATURES WILL OPEN THE WEEKEND WITH TEMPERATURES RUNNING 15 TO
20 DEGREES BELOW NORMAL.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1220 AM EST...SNOW WAS WORKING ACROSS MOST OF THE REGION
NOW...MORE LIKE PERIODS OF SNOW WITH ELEMENTS OF MODERATE
SNOW...BACKING OFF TO FLURRIES. PREVIOUS FORECAST LOOKED RIGHT ON
TRACK WITH US INCLUDING OVERNIGHT LOWS SO VERY LITTLE TO CHANGE WITH
THIS UPDATE.
LOW PRESSURE WAS NEAR WATERTOWN NY HEADING EAST AND RESPONSIBLE FOR
THIS LATEST BOUT OF SNOW. THE LOW WILL CONTINUE TO MOVE
EASTWARD...AND WILL START TO TRANSITION TO A SECONDARY LOW OFF THE
COAST OF SOUTHERN NEW ENGLAND TOWARDS DAYBREAK.
THE LATEST 3KM HRRR AND THE NEW 00Z NAM BOTH SHOW A MINIMUM IN
PRECIP OVERNIGHT EXPECTED ACROSS THE CAPITAL REGION/SCHOHARIE
VALLEY. THE HIGHEST AMOUNTS LOOK TO BE IN THE SRN ADIRONDACKS AND
SARATOGA AREA...THANKS TO THE STRONG SOUTHERLY FLOW UPSLOPING THE
HIGHER TERRAIN.
BECAUSE OF THIS...JUST ABOUT AN INCH OR TWO WILL FALL IN THE CAPITAL
REGION OVERNIGHT...WITH UP TO SEVERAL INCHES ACROSS NORTHERN AREAS
BY DAYBREAK.
TEMPS OVERNIGHT WILL MAINLY BE STEADY IN THE MID TO UPPER 20S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
WINTER WEATHER ADVISORIES CONTINUED UNTIL 9 AM FRIDAY FOR THE
MOHAWK VALLEY...SOUTHERN ADIRONDACKS AND LAKE GEORGE SARATOGA
REGION.
WINTER WEATHER ADVISORIES UNTIL NOON FOR SCHOHARIE COUNTY...THE
GREATER CAPITAL REGION...NRN TACONICS...SRN VT...AND THE NRN
BERKSHIRES.
CONTINUING THE NEAR TERM DISCUSSION ON SNOWFALL AMOUNTS...WHERE THE
LATEST 09Z SREF PLUME GIVES KALB MEAN AMOUNTS 0.20-0.25" OF
QPF...THE 12Z GEFS PLUME IS AROUND 0.30". THE OPERATIONAL GUIDANCE
RANGES FROM 0.25-0.35". AGAIN...USING A 13-15:1 SNOW TO LIQUID
RATIOS YIELD AROUND 4". THE HIGHEST TALLIES MAY BE ALONG THE SE
FOOTHILLS OF THE SRN DACKS WHERE A HALF INCH OF QPF MAY YIELD SOME
5-7" AMOUNTS. THE PRIMARY SFC LOW WEAKENS OVER NRN NY AND UPSTATE
VT...AND SHORT-WAVE ENERGY SHIFTS TO THE COAST...WHERE A SFC LOW
WILL LIKELY SPIN UP NEAR LONG ISLAND. THE SNOW MAY INCREASE IN
INTENSITY A BIT OVER THE NRN TACONICS...BERKS...AND SRN GREENS. IN
A GENERAL SENSE...THIS LOOKS LIKE A 2-6" SNOWFALL EVENT FOR THE
ENTIRE REGION...EXCEPT 2-4" OVER THE ERN CATSKILLS...MID
HUDSON...SRN TACONICS...SRN BERKS...AND NW CT. IT SHOULD BE
STRESSED THAT LOCATIONS LIKE THE CAPITAL REGION...MAY BE ON THE
LOWER END OF THE RANGE...BUT THERE COULD BE A SOCIETAL IMPACT ON
THE MORNING COMMUTE WITH SNOW COVERED ROADS...AND SOME VERY
SLIPPERY SURFACES. THE LATEST WPC SNOW GUIDANCE SHOWS A HIGH CHC
TO LIKELY PROBABILITY OF 4 INCHES OR GREATER OF SNOWFALL BASICALLY
FROM ALBANY/THE MOHAWK VALLEY/NRN BERKS NORTHWARD BTWN 00Z/FRI TO
00Z/SAT.
THE H850 CIRCULATION MOVES EAST OF BOSTON BY 00Z/SAT...COLDER AIR
WRAPS INTO THE REGION WITH AN ARCTIC FRONT DIPPING SOUTH. H850
TEMPS DROP TO -12C TO -17C FROM NW TO SE. EXPECT HIGH TEMPS TO BE
IN THE LOWER TO MID 20S NORTHWEST OF THE CAPITAL DISTRICT...AND
U20S TO L30S TO THE SOUTH AND EAST. THE WINDS WILL INCREASE FROM
THE NW AT 10-20 MPH WITH SOME GUSTS AROUND 30 MPH. THE STRONGER
COLD ADVECTION WILL OCCUR FRI NIGHT.
FRI NIGHT INTO SATURDAY...THE COASTAL WAVE QUICKLY MOVES NORTHEAST
AND THE ARCTIC FRONT SLIPS SOUTH. THE LOW-LEVEL SFC PRESSURE
GRADIENT STRENGTHENS BETWEEN THE DEPARTING SFC CYCLONE...AND THE
SFC ANTICYCLONE BUILDING IN FROM THE OH VALLEY...ERN GREAT LAKES
REGION...AND SE CANADA. WIND CHILLS WILL PLUMMET TO -10 TO -30
DEGREES BELOW ZERO WITH BLUSTERY NW WINDS OF 10 TO 20 MPH WITH
SOME GUSTS IN THE 30-40 MPH RANGE. WIND CHILL ADVISORIES AND OR
WARNINGS MAY BE NEEDED FOR MOST OF THE AREA FRI NIGHT INTO
SATURDAY MORNING. LOWS WILL BE 10 TO 15 DEGREES BELOW ZERO OVER
THE SRN DACKS REGION. ZERO TO 10 BELOW NORTH OF THE CAPITAL
REGION...AND SINGLE DIGITS TO THE SOUTH AND EAST. THE MET MOS
VALUES WERE MUCH COLDER THAN THE MAV MOS HERE. THE WINDS WILL
GRADUALLY ABATE SATURDAY AFTERNOON WITH THE SFC RIDGE BUILDING
IN...BUT IT WILL BE FRIGID WITH TEMPS STILL IN THE SINGLE DIGITS
TO THE TEENS FOR HIGHS.
SATURDAY NIGHT...ANOTHER CLIPPER AND ARCTIC FRONT DIVES SOUTH OF THE
GREAT LAKES REGION WITH A REINFORCING SHOT OF ARCTIC AIR. THIS
SYSTEM LOOKS MORE MOISTURE STARVED. THE THREAT FOR SCT SNOW
SHOWERS INCREASES NORTH AND WEST OF THE CAPITAL REGION. LOWS WILL
BE IN THE SINGLE NUMBERS FROM THE TRI CITIES SOUTH AND EAST AND
ZERO TO 10 BELOW TO THE NORTH. LIGHT SNOW ACCUMS OF AN INCH OR
LESS WILL BE COMMON WITH THE CLIPPER.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THIS WILL BE A PERIOD MARKED BY VERY COLD TEMPERATURES...SOME 5 TO
25 DEGREES BELOW NORMAL. IT BEGINS WITH THE PASSAGE OF AN ARCTIC
COLD FRONT ON SUNDAY. LOW PRESSURE PASSING OFF THE MID-ATLANTIC AND
CAROLINAS COAST WILL CONTINUE A COLD NORTHERLY FLOW...AND PROVIDE US
WITH A CHANCE OF SNOW SUNDAY NIGHT AND MONDAY PRIMARILY FOR OUR
SOUTHERN ZONES.
MONDAY NIGHT WILL BE ONE OF THE COLDEST IN RECENT MEMORY...WITH LOW
TEMPERATURES RANGING FROM 5 TO 10 DEGREES BELOW ZERO SOUTH AND
VALLEYS...TO AROUND 20 BELOW IN THE ADIRONDACKS. WE COULD BE
FLIRTING WITH RECORDS AT SOME LOCATIONS ACROSS SOUTHERN AREAS.
SOME SUNSHINE UNDER HIGH PRESSURE WILL ALLOW FOR A GOOD REBOUND IN
TEMPERATURES...BUT THEY WILL STILL BE RUNNING BELOW NORMAL.
A REINFORCING COLD SURGE ON THURSDAY WILL ENSURE THAT THE DEEP
FREEZE CONTINUES. THE GOOD NEWS IS THAT ANY SNOWFALL WILL BE ON THE
LOW SIDE AS LONG AS THE MONDAY STORM STAYS WELL OFF TO OUR SOUTH.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
PERIODS/OCCASIONAL BURSTS OF SNOW WILL CONTINUE TO MOVE ACROSS THE
REGION. DUE TO THIS...VISIBILITIES WILL BE A CHALLENGE TO FORECAST
AS WE WILL OBSERVE MVFR TO IFR IN SHORT/BRIEF BURSTS. AT THE
MINIMUM...CIGS WILL BE SOLIDLY IN MVFR AT ALL TAF SITES THE
REMAINDER OF THE OVERNIGHT PERIOD.
TRENDS IN THE SHORT TERM MODELS HINT A BAND OF SNOW MOVING THROUGH
THE HUDSON RIVER VALLEY AROUND SUNRISE WHERE THE BEST POTENTIAL FOR
IFR CONDITIONS AT ALL TAF LOCATIONS. THEREAFTER...DURING THE MID
MORNING HOURS...CONDITIONS WILL IMPROVE WITH RESPECT TO DIMINISHING
TRENDS IN THE SNOW AND LOW CIGS. THEN A WIND SHIFT WILL RESULT IN
AN INCREASE OF MAGNITUDES WHERE SOME BLOWING SNOW COULD RESULT FOR
THE REMAINDER OF THE DAY.
WINDS OVERNIGHT WILL GENERALLY BE SOUTHERLY AROUND 10KTS WITH SOME
GUSTS IN KALB. WINDS WILL QUICKLY SHIFTS TO THE WEST THEN NORTHWEST
FRIDAY MORNING WITH 10-15KTS WITH GUSTS AT OR ABOVE 20KTS.
OUTLOOK...
FRIDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
SATURDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY SLIGHT CHANCE OF SHSN.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDRO PROBLEMS ARE EXPECTED THROUGH THE NEXT 5 DAYS.
SNOW WILL FALL TONIGHT...WITH LIGHT TO MODERATE AMOUNTS ACROSS THE
HYDRO SERVICE AREA. SNOW ACCUMULATIONS WILL GENERALLY RANGE FROM 2
TO 6 INCHES.
ADDITIONAL SNOW SHOWERS ARE POSSIBLE FRIDAY EVENING WITH
GENERALLY MINOR ADDITIONAL ACCUMULATIONS.
THERE IS ALSO A SLIGHT TO LOW CHANCE OF SNOW SUNDAY NIGHT INTO
MONDAY.
ICE WILL CONTINUE TO THICKEN ON RIVERS...STREAMS...CREEKS...LAKES
AND OTHER BODIES OF WATER.
THE EAGLE BRIDGE GAGE ON THE HOOSIC RIVER CONTINUES TO BE HAMPERED
BY ICE EFFECTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR NYZ047>054.
WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR NYZ032-
033-038>043-082>084.
MA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR MAZ001.
VT...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VTZ013>015.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...FRUGIS/HWJIV
SHORT TERM...WASULA
LONG TERM...ELH
AVIATION...BGM
HYDROLOGY...WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1220 AM EST FRI JAN 30 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE ACROSS NORTHERN NEW YORK
TONIGHT...AND THEN MOVE EAST OF NEW ENGLAND BY TOMORROW AFTERNOON
BRINGING A LIGHT TO MODERATE SNOWFALL TO THE REGION. AN ARCTIC
FRONT WILL CROSS THE REGION TOMORROW AFTERNOON INTO TOMORROW NIGHT
WITH A SURGE OF ARCTIC AIR...AND BITTERLY COLD WIND CHILLS. FRIGID
TEMPERATURES WILL OPEN THE WEEKEND WITH TEMPERATURES RUNNING 15 TO
20 DEGREES BELOW NORMAL.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1220 AM EST...SNOW WAS WORKING ACROSS MOST OF THE REGION
NOW...MORE LIKE PERIODS OF SNOW WITH ELEMENTS OF MODERATE
SNOW...BACKING OFF TO FLURRIES. PREVIOUS FORECAST LOOKED RIGHT ON
TRACK WITH US INCLUDING OVERNIGHT LOWS SO VERY LITTLE TO CHANGE WITH
THIS UPDATE.
LOW PRESSURE WAS NEAR WATERTOWN NY HEADING EAST AND RESPONSIBLE FOR
THIS LATEST BOUT OF SNOW. THE LOW WILL CONTINUE TO MOVE
EASTWARD...AND WILL START TO TRANSITION TO A SECONDARY LOW OFF THE
COAST OF SOUTHERN NEW ENGLAND TOWARDS DAYBREAK.
THE LATEST 3KM HRRR AND THE NEW 00Z NAM BOTH SHOW A MINIMUM IN
PRECIP OVERNIGHT EXPECTED ACROSS THE CAPITAL REGION/SCHOHARIE
VALLEY. THE HIGHEST AMOUNTS LOOK TO BE IN THE SRN ADIRONDACKS AND
SARATOGA AREA...THANKS TO THE STRONG SOUTHERLY FLOW UPSLOPING THE
HIGHER TERRAIN.
BECAUSE OF THIS...JUST ABOUT AN INCH OR TWO WILL FALL IN THE CAPITAL
REGION OVERNIGHT...WITH UP TO SEVERAL INCHES ACROSS NORTHERN AREAS
BY DAYBREAK.
TEMPS OVERNIGHT WILL MAINLY BE STEADY IN THE MID TO UPPER 20S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
WINTER WEATHER ADVISORIES CONTINUED UNTIL 9 AM FRIDAY FOR THE
MOHAWK VALLEY...SOUTHERN ADIRONDACKS AND LAKE GEORGE SARATOGA
REGION.
WINTER WEATHER ADVISORIES UNTIL NOON FOR SCHOHARIE COUNTY...THE
GREATER CAPITAL REGION...NRN TACONICS...SRN VT...AND THE NRN
BERKSHIRES.
CONTINUING THE NEAR TERM DISCUSSION ON SNOWFALL AMOUNTS...WHERE THE
LATEST 09Z SREF PLUME GIVES KALB MEAN AMOUNTS 0.20-0.25" OF
QPF...THE 12Z GEFS PLUME IS AROUND 0.30". THE OPERATIONAL GUIDANCE
RANGES FROM 0.25-0.35". AGAIN...USING A 13-15:1 SNOW TO LIQUID
RATIOS YIELD AROUND 4". THE HIGHEST TALLIES MAY BE ALONG THE SE
FOOTHILLS OF THE SRN DACKS WHERE A HALF INCH OF QPF MAY YIELD SOME
5-7" AMOUNTS. THE PRIMARY SFC LOW WEAKENS OVER NRN NY AND UPSTATE
VT...AND SHORT-WAVE ENERGY SHIFTS TO THE COAST...WHERE A SFC LOW
WILL LIKELY SPIN UP NEAR LONG ISLAND. THE SNOW MAY INCREASE IN
INTENSITY A BIT OVER THE NRN TACONICS...BERKS...AND SRN GREENS. IN
A GENERAL SENSE...THIS LOOKS LIKE A 2-6" SNOWFALL EVENT FOR THE
ENTIRE REGION...EXCEPT 2-4" OVER THE ERN CATSKILLS...MID
HUDSON...SRN TACONICS...SRN BERKS...AND NW CT. IT SHOULD BE
STRESSED THAT LOCATIONS LIKE THE CAPITAL REGION...MAY BE ON THE
LOWER END OF THE RANGE...BUT THERE COULD BE A SOCIETAL IMPACT ON
THE MORNING COMMUTE WITH SNOW COVERED ROADS...AND SOME VERY
SLIPPERY SURFACES. THE LATEST WPC SNOW GUIDANCE SHOWS A HIGH CHC
TO LIKELY PROBABILITY OF 4 INCHES OR GREATER OF SNOWFALL BASICALLY
FROM ALBANY/THE MOHAWK VALLEY/NRN BERKS NORTHWARD BTWN 00Z/FRI TO
00Z/SAT.
THE H850 CIRCULATION MOVES EAST OF BOSTON BY 00Z/SAT...COLDER AIR
WRAPS INTO THE REGION WITH AN ARCTIC FRONT DIPPING SOUTH. H850
TEMPS DROP TO -12C TO -17C FROM NW TO SE. EXPECT HIGH TEMPS TO BE
IN THE LOWER TO MID 20S NORTHWEST OF THE CAPITAL DISTRICT...AND
U20S TO L30S TO THE SOUTH AND EAST. THE WINDS WILL INCREASE FROM
THE NW AT 10-20 MPH WITH SOME GUSTS AROUND 30 MPH. THE STRONGER
COLD ADVECTION WILL OCCUR FRI NIGHT.
FRI NIGHT INTO SATURDAY...THE COASTAL WAVE QUICKLY MOVES NORTHEAST
AND THE ARCTIC FRONT SLIPS SOUTH. THE LOW-LEVEL SFC PRESSURE
GRADIENT STRENGTHENS BETWEEN THE DEPARTING SFC CYCLONE...AND THE
SFC ANTICYCLONE BUILDING IN FROM THE OH VALLEY...ERN GREAT LAKES
REGION...AND SE CANADA. WIND CHILLS WILL PLUMMET TO -10 TO -30
DEGREES BELOW ZERO WITH BLUSTERY NW WINDS OF 10 TO 20 MPH WITH
SOME GUSTS IN THE 30-40 MPH RANGE. WIND CHILL ADVISORIES AND OR
WARNINGS MAY BE NEEDED FOR MOST OF THE AREA FRI NIGHT INTO
SATURDAY MORNING. LOWS WILL BE 10 TO 15 DEGREES BELOW ZERO OVER
THE SRN DACKS REGION. ZERO TO 10 BELOW NORTH OF THE CAPITAL
REGION...AND SINGLE DIGITS TO THE SOUTH AND EAST. THE MET MOS
VALUES WERE MUCH COLDER THAN THE MAV MOS HERE. THE WINDS WILL
GRADUALLY ABATE SATURDAY AFTERNOON WITH THE SFC RIDGE BUILDING
IN...BUT IT WILL BE FRIGID WITH TEMPS STILL IN THE SINGLE DIGITS
TO THE TEENS FOR HIGHS.
SATURDAY NIGHT...ANOTHER CLIPPER AND ARCTIC FRONT DIVES SOUTH OF THE
GREAT LAKES REGION WITH A REINFORCING SHOT OF ARCTIC AIR. THIS
SYSTEM LOOKS MORE MOISTURE STARVED. THE THREAT FOR SCT SNOW
SHOWERS INCREASES NORTH AND WEST OF THE CAPITAL REGION. LOWS WILL
BE IN THE SINGLE NUMBERS FROM THE TRI CITIES SOUTH AND EAST AND
ZERO TO 10 BELOW TO THE NORTH. LIGHT SNOW ACCUMS OF AN INCH OR
LESS WILL BE COMMON WITH THE CLIPPER.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THIS WILL BE A PERIOD MARKED BY VERY COLD TEMPERATURES...SOME 5 TO
25 DEGREES BELOW NORMAL. IT BEGINS WITH THE PASSAGE OF AN ARCTIC
COLD FRONT ON SUNDAY. LOW PRESSURE PASSING OFF THE MID-ATLANTIC AND
CAROLINAS COAST WILL CONTINUE A COLD NORTHERLY FLOW...AND PROVIDE US
WITH A CHANCE OF SNOW SUNDAY NIGHT AND MONDAY PRIMARILY FOR OUR
SOUTHERN ZONES.
MONDAY NIGHT WILL BE ONE OF THE COLDEST IN RECENT MEMORY...WITH LOW
TEMPERATURES RANGING FROM 5 TO 10 DEGREES BELOW ZERO SOUTH AND
VALLEYS...TO AROUND 20 BELOW IN THE ADIRONDACKS. WE COULD BE
FLIRTING WITH RECORDS AT SOME LOCATIONS ACROSS SOUTHERN AREAS.
SOME SUNSHINE UNDER HIGH PRESSURE WILL ALLOW FOR A GOOD REBOUND IN
TEMPERATURES...BUT THEY WILL STILL BE RUNNING BELOW NORMAL.
A REINFORCING COLD SURGE ON THURSDAY WILL ENSURE THAT THE DEEP
FREEZE CONTINUES. THE GOOD NEWS IS THAT ANY SNOWFALL WILL BE ON THE
LOW SIDE AS LONG AS THE MONDAY STORM STAYS WELL OFF TO OUR SOUTH.
&&
.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
FLYING CONDITIONS ARE CURRENTLY VFR AT ALL SITES...BUT THIS ISN/T
EXPECT TO LAST MUCH LONGER. A CLIPPER SYSTEM WILL BRING A PERIOD
OF LIGHT SNOW TO THE REGION BEGINNING LATER THIS EVENING. KENX
RADAR ALREADY SHOWS RETURNS CLOSE TO THE REGION...AND AS LOW
LEVELS OF THE ATMOSPHERE MOISTEN UP...SNOW WILL BEGIN BY 03Z-04Z
AT THE LATEST. SNOW WILL CONTINUE THROUGH THE OVERNIGHT HOURS WITH
IFR CONDITIONS...AND PERHAPS LIFR AT TIMES. WHILE STEADY SNOW WILL
END BY AROUND DAYBREAK...SOME LINGERING SNOW SHOWERS MAY CONTINUE
THROUGH THE MID TO LATE MORNING HOURS. VFR CONDITIONS LOOK TO
RETURN FOR THE VALLEY SITES BY AFTN...ALTHOUGH KPSF MAY SEE
LINGERING MVFR CIGS INTO THE AFTN HOURS.
WINDS WILL BE SOUTHERLY AT 5-10 KTS AHEAD OF THE CLIPPER SYSTEM.
THIS LOOKS TO CONTINUE THROUGH THE OVERNIGHT HOURS. WINDS WILL
START TO SWITCH TO THE W-SW AROUND DAYBREAK AND BECOME NW BEHIND
THE STORM/S COLD FRONT...WHICH WILL BE PASSING BETWEEN THE LATE
MORNING AND EARLY AFTN HOURS. WINDS WILL INCREASE AND BECOME GUSTY
BEHIND THE ARCTIC COLD FRONT FOR THE AFTN...WITH GUSTS OVER 20 KTS
POSSIBLE...ESP FOR KALB/KPSF.
OUTLOOK...
FRIDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
SATURDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY SLIGHT CHANCE OF SHSN.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDRO PROBLEMS ARE EXPECTED THROUGH THE NEXT 5 DAYS.
SNOW WILL FALL TONIGHT...WITH LIGHT TO MODERATE AMOUNTS ACROSS THE
HYDRO SERVICE AREA. SNOW ACCUMULATIONS WILL GENERALLY RANGE FROM 2
TO 6 INCHES.
ADDITIONAL SNOW SHOWERS ARE POSSIBLE FRIDAY EVENING WITH
GENERALLY MINOR ADDITIONAL ACCUMULATIONS.
THERE IS ALSO A SLIGHT TO LOW CHANCE OF SNOW SUNDAY NIGHT INTO
MONDAY.
ICE WILL CONTINUE TO THICKEN ON RIVERS...STREAMS...CREEKS...LAKES
AND OTHER BODIES OF WATER.
THE EAGLE BRIDGE GAGE ON THE HOOSIC RIVER CONTINUES TO BE HAMPERED
BY ICE EFFECTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR NYZ047>054.
WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR NYZ032-
033-038>043-082>084.
MA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR MAZ001.
VT...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VTZ013>015.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...FRUGIS/HWJIV
SHORT TERM...WASULA
LONG TERM...ELH
AVIATION...FRUGIS
HYDROLOGY...WASULA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
900 AM EST FRI JAN 30 2015
.DISCUSSION...WEAK FRONTAL BOUNDARY STRETCHING FROM THE BIG BEND
REGION TO NORTH OF JACKSONVILLE EARLY THIS MORNING...MARKED BY A
THIN BAND OF LIGHT SHOWERS AND A QUICK NW WIND SHIFT BEHIND IT.
BAND HAS BEEN WEAKENING OVER LAND AS IT MOVER FURTHER SOUTH AND BOTH
THE WRF AND HRRR SHOW LITTLE MORE THAN A SPRINKLE OR TWO AS THE
BOUNDARY MOVES THROUGH THE CENTRAL PENINSULA THROUGH THE REST OF THE
DAY. THIS APPEARS REASONABLE GIVEN THE EXTREMELY DRY AIRMASS IN
PLACE ACROSS THE AREA WITH MORNING SOUNDINGS AT TAMPA AND XMR
SHOWING PWATS AROUND 0.68" AND A GOOD INVERSION AROUND 3500FT. WHILE
A SPRINKLE CAN`T BE RULED OUT...WILL KEEP FORECAST OVER LAND DRY
WITH MAIN IMPACTS A PERIOD OF CLOUDINESS WITH THE FRONT MOVING FROM
NORTH TO SOUTH THROUGH THE DAY.
GIVEN CURRENT TIMING OF FRONT/WIND SHIFT ARRIVING INTO REGION AROUND
MIDDAY...WILL HOLD HIGHS ACROSS NORTHERN LAKE AND VOLUSIA COUNTIES
IN THE MID 60S...WITH UPPER 60S/AROUND 70S ACROSS THE REMAINDER OF
THE I-4 CORRIDOR. POINTS FURTHER SOUTH WILL REACH INTO THE LOW 70S.
&&
.AVIATION...PREVAILING VFR. APPROACHING FRONTAL BOUNDARY WILL BRING
1-2HRS OF CIGS FL020-030 TO EACH SITE AS IT MOVES THROUGH FROM N-S
AFTER 14Z. A FEW SPRINKLES POSSIBLE WITH PASSAGE. WIND SHIFT TO N-NW
WITH G20KTS BEHIND FRONT STARTING AROUND 16Z FOR KLEE-KDAB AND BY
23Z FOR KSUA.
&&
.MARINE...WEST-NORTHWEST FLOW 10-15KTS THIS MORNING ALONG COAST AND
BUOYS AHEAD OF WEAK FRONTAL BOUNDARY ACROSS NORTH FLORIDA. FRONT
WILL SLOWLY MOVE THROUGH PENINSULA THROUGH THE REST OF THE DAY WITH
WINDS SHIFTING NW 15-20KTS NORTH OF THE CAPE BY MIDDAY AND OVER THE
REMAINDER OF THE WATERS THROUGH THE AFTERNOON. SOLID 20KTS EXPECTED
OVER OFFSHORE WATERS BY THIS EVENING AS WINDS VEER NORTHERLY. SEAS
INITIALLY 3-5FT THIS MORNING RAMPING UP TO 5-7FT IN THE ADVISORY
AREA BY SUNSET AS NORTH WIND SURGE COUNTERS THE GULF STREAM.
NO CHANGES TO ONGOING ADVISORIES WHICH START AROUND MIDDAY FOR THE
OFFSHORE VOLUSIA COUNTY WATERS...EARLY AFTERNOON FOR THE OFFSHORE
BREVARD WATERS...AND THIS EVENING FOR THE TREASURE COAST WATERS
INCLUDING THE NEARSHORE PORTION OF THE GULFSTREAM.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM SATURDAY
FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM
OFFSHORE.
SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM SATURDAY
FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM
OFFSHORE.
SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 AM SATURDAY
FROM SEBASTIAN INLET TO JUPITER INLET OUT TO 60 NM OFFSHORE.
&&
$$
MOSES/PENDERGRAST
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
549 AM CST FRI JAN 30 2015
.SHORT TERM...
313 AM CST
THROUGH TONIGHT...
WEATHER NIL IN THE SHORT TERM TIME FRAME AS HIGH PRESSURE MOVES
ACROSS THE REGION THROUGH TONIGHT WITH SOUTHERLY WINDS AND WARM AIR
ADVECTION KICKING IN LATE TONIGHT AS THE HIGH MOVES EAST OF THE
REGION.
IZZI
&&
.LONG TERM...
313 AM CST
SATURDAY THROUGH THURSDAY...
ALL EYES IN THE LONG TERM ARE ON THE COMPLEX WEEKEND STORM SYSTEM
WHICH LOOKS LIKELY TO BRING SHOVEL-ABLE SNOWFALL TO THE CWA SATURDAY
NIGHT AND SUNDAY. MAIN SHORTWAVE ENERGY RESPONSIBLE FOR THE
DEVELOPING STORM SYSTEM THIS WEEKEND IS RELATIVELY COMPACT SHORTWAVE
ABOUT 700 MILES WEST OF THE BRITISH COLUMBIA COAST. THIS SHORTWAVE
IS FORECAST TO MOVE ONSHORE THIS EVENING AND THEN DIVE SOUTHEAST
INTO THE NORTHERN ROCKIES AND HIGH PLAINS BY SATURDAY
EVENING...WHILE WHILE PHASING WITH SHORTWAVE ENERGY CURRENTLY OVER
INTERIOR ALASKA.
THE TRACK OF THESE SHORTWAVES WILL LIKELY BE AFFECTED BY A VIGOROUS
SHORTWAVE PIVOTING AROUND THE HUDSON BAY LOW AND A LARGE CLOSED LOW
DEVELOPING OVER THE SOUTHWEST CONUS AND DROPPING SOUTH INTO NORTHERN
OLD MEXICO. THE COMPLEXITY OF THIS PATTERN LENDS ITSELF TO HIGHER
THAN AVERAGE UNCERTAINTY WITH RESPECT TO THE EVENTUAL EVOLUTION OF
THE WEEKEND SYSTEM...ITS INTENSITY...QPF AMOUNTS...AND PLACEMENT OF
THE HEAVIEST QPF AND SNOWFALL. GIVEN THE NUMBER OF PLAYERS INVOLVED
AND THE FACT THE PRIMARY SHORTWAVE IS STILL OFFSHORE IT IS QUITE
PLAUSIBLE THAT THERE COULD BE ADDITIONAL LARGE SWINGS IN THE
FORECAST MODELS` PREDICTED TRACK/INTENSITY OF THIS SYSTEM...MUCH
LIKE WHAT WAS SEEN IN THE PAST FEW DAYS WITH THE MAIN STORY 24 HOURS
AGO BEING THE BIG SOUTHWARD TRENDS IN THE SOLUTIONS...FOLLOWED BY A
FORECAST TRACK SHIFT OF NEARLY 200 MILES FARTHER NORTH IN THE 00Z
ECMWF TONIGHT VS ITS RUN 24 HOURS AGO.
OK...ENOUGH ABOUT THE UNCERTAINTIES AND ON TO THE CURRENT
EXPECTATIONS OF THE SYSTEM. AS SHORTWAVE DROPS SOUTHEAST INTO THE
NORTHERN ROCKIES LOOK FOR A COLORADO LOW TO DEVELOP SATURDAY...THEN
TRACK EASTWARD ACROSS SOUTHERN ILLINOIS SUNDAY AFTERNOON AND
EVENTUALLY EAST TO THE MID ATLANTIC REGION BY MONDAY MORNING. THE
STRONG SHORTWAVE PIVOTING AROUND THE HUDSON BAY VORTEX AND ITS
ASSOCIATED SURFACE LOW ARE STILL PROGGED TO DRIVE A COLD FRONT SOUTH
ACROSS THE CWA SATURDAY WITH THE FRONT EVENTUALLY STALLING OUT TO
OUT SOUTH SATURDAY NIGHT AND SETTING THE STAGE FOR WHAT LOOKS TO BE
A LONG DURATION WAA SNOW EVENT. LOOKING AT THE 280-295K ISENTROPIC
SURFACES MODELS HAVE UPGLIDE STARTING SAT EVENING AND CONTINUING
THROUGH SUNDAY MORNING WITH WEAK/BROAD DEFORMATION BAND LIKELY TO
KEEP SNOWS GOING THROUGH MUCH OF THE DAY SUNDAY.
LOW/MID LEVEL PARCELS OVER THE AREA SAT NIGHT/SUNDAY MORNING ARE
PROGGED TO HAVE ORIGINATED FROM THE WESTERN GULF...SO THIS SYSTEM
WILL HAVE ACCESS TO MUCH MORE MOISTURE THAN MOST OF OUR SYSTEMS HAVE
HAD THIS WINTER...THOUGH IT STILL WILL BE FEEDING OFF A RECYCLED
CONTINENTAL POLAR AIRMASS FOLLOWING TODAY`S FROPA IN THE GULF.
STRONGEST ASCENT/HEAVIEST SNOWFALL IN THIS EVENING`S RUNS LOOKS TO
BE CENTERED ON SAT NIGHT AND OVER OUR SOUTHERN CWA. CURRENT RUN`S
THERMODYNAMICS FORECAST MOISTURE/OMEGA REALLY POINT TOWARD
SNOW:LIQUID RATIOS NEAR CLIMO (10-12:1) FOR THE MAJORITY OF THE
EVENT WHICH GIVEN LATEST MODEL CONSENSUS/WPC QPF FORECAST WOULD
SUGGEST WIDESPREAD 3-6" AMOUNTS ACROSS THE CWA WITH LOCALLY HEAVIER
AMOUNTS TO NEAR 8 INCHES IN OUR SOUTHERN CWA. GIVEN THE LONG
DURATION OF THE EVENT...WARNING CRITERIA IS 8 INCHES IN 24 HOURS
WHICH IS POSSIBLE BUT GIVEN ALL THE UNCERTAINTIES CONFIDENCE IS NOT
HIGH IN IF AND WHERE THIS WOULD OCCUR SO NO WATCH IS PLANNED AT THIS
TIME.
AS ARCTIC AIR SPREADS SOUTHWARD ON THE BACK SIDE OF THE SYSTEM
SUNDAY AFTERNOON AND SUNDAY NIGHT THERE COULD BE SOME LAKE ENHANCED
SNOW THAT COULD TRANSITION TO PURE LAKE EFFECT SNOW SHOWERS SUNDAY
NIGHT. FORECAST SOUNDINGS DO SHOW MODERATELY STRONG LOW LEVEL
INSTABILITY BELOW THE FRONTAL INVERSION...BUT INVERSION HEIGHTS ARE
FORECAST TO ONLY BE AROUND 5-6KFT SO LAKE EFFECT CONVECTION WOULD BE
SHALLOW. CURRENT FORECAST THERMODYNAMICS AND FORECAST OF VERY DRY
AIR ATOP A SOLID INVERSION...IT REALLY DOESNT LOOK TO FAVOR LAKE
EFFECT BEING A BIG PLAYER IN SNOWFALL TOTALS. CAN`T RULE OUT A BIT
OF ENHANCEMENT TO THE SNOWFALL OVER NORTHEAST ILLINOIS SUN AFTERNOON
AND NIGHT...BUT GIVEN THE CURRENT MODEL RUNS THE CONTRIBUTION TO
TOTALS FROM THE LAKE LOOK TO BE TRIVIAL COMPARED TO THE SYNOPTIC
SNOWS.
PATTERN LOOKS TO REMAIN VERY PROGRESSIVE IN THE WAKE OF THE
SYSTEM...SO ARCTIC AIR WILL NOT HAVE TIME TO GET WELL ENTRENCHED
BEFORE WARM AIR ADVECTION DEVELOPS LATER MONDAY IN ADVANCE OF THE
NEXT CLIPPER WHICH THIS EVENING`S RUN HAVE TRACKING ACROSS WISCONSIN
KEEPING US IN THE RELATIVELY DRY WARM SECTOR TUESDAY. ANOTHER SURGE
OF ARCTIC IS PROGGED TO ARRIVE TOWARD MIDWEEK WITH SOME SNOW
POSSIBLY ACCOMPANYING IT. WHILE IT LOOKS TO BE VERY COLD
MIDWEEK...GFS AND ECMWF BEYOND DAY 7 SUGGEST THE PATTERN WILL REMAIN
PROGRESSIVE WITH ARCTIC AIR NOT STICKING AROUND WITH LONG WAVE
TROUGH MIGRATING EAST OUT OF THE AREA.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* NNWLY WINDS BACKING TO SWLY THIS AFTERNOON. SPEED LESS THAN 10KT
THROUGH THE DAY.
KREIN
//DISCUSSION...UPDATED 12Z...
HIGH PRESSURE SLIDING ACROSS THE REGION TODAY WILL KEEP SKIES
MOSTLY CLEAR. WINDS WILL ALSO DIMINISH A BIT FROM THE INITIAL
8-9KT THIS MORNING AND BACK TO SWLY THIS AFTERNOON AS THE CENTER
OF THE HIGH MOVES ACROSS NRN IL AND INTO CNTRL INDIANA. WINDS WILL
THEN BE LIGHT AND SWLY THROUGH THE REMAINDER OF THE FORECAST
PERIOD AS THE HIGH SETTLES INTO THE OHIO VALLEY.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...SNOW. IFR CIGS/VIS LIKELY.
SUNDAY...SNOW THROUGH THE DAY...TAPERING OFF OVERNIGHT. MVFR
CIGS/VIS LIKELY. PERIODS IFR CONDITIONS POSSIBLE.
MONDAY...VFR/WX NIL EARLY. SLIGHT CHANCE SNOW OVERNIGHT. MVFR
CIGS/VIS LIKELY.
TUESDAY AND WEDNESDAY...CHANCE OF SNOW. PERIODS OF MVFR CIGS/VIS
LIKELY.
THURSDAY...VFR/WX NIL.
KREIN
&&
.MARINE...
230 AM CST
A PROGRESSIVE...ACTIVE PATTERN WILL CONTINUE FOR LAKE MICHIGAN FOR
THE NEXT SEVERAL DAYS. WINDS ARE SLOWLY DIMINISHING OVER THE LAKE
AND WILL LET THE GALE AND HEAVY FREEZING SPRAY WARNINGS EXPIRE AT
300 AM. HOWEVER...WITH LAKE MICHIGAN STILL UNDER A RELATIVELY
STRONG PRESSURE GRADIENT...A SMALL CRAFT ADVISORY WILL BE ISSUED
FOR BOTH THE ILLINOIS NEARSHORE WATERS AS WINDS ARE STILL ARND 30
KT EARLY THIS MORNING...BUT SHOULD DROP OFF TO 10-15KT BY MID DAY.
RESIDUAL WAVE ACTION FROM THE PERSISTENT NORTHERLY WINDS SHOULD
KEEP WAVES ABOVE 4 FT THROUGH THIS AFTERNOON. AS THE AXIS OF HIGH
PRESSURE MOVES ACROSS THE LAKE THIS EVENING A BRIEF PERIOD OF
RELATIVELY MILD CONDITONS WILL SET UP...BUT THE HIGH WILL QUICKLY
SETTLE INTO THE OHIO VALLEY TONIGHT AS LOW PRESSURE TRACKS ACROSS
THE UPPER GREAT LAKES REGION. THIS SYSTEM WILL DRAG A COLD FRONT
ACROSS THE LAKE SATURDAY. FOLLOWING THE PASSAGE OF THE COLD
FRONT...STRONG HIGH PRESSURE WILL BUILD ACROSS THE CNTRL PLAINS
AND UPPER GREAT LAKES SATUDAY NIGHT AND SUNDAY WHILE LOW PRESSURE
DEVELOPS OVER THE LOWER OHIO VALLEY SUNDAY AFTERNOON. AN EXTENDED
PERIOD OF NELY WINDS OF 25-30 KT WILL BEGIN FOLLOWING THE FRONTAL
PASSAGE AND PERSIST INTO EARLY NEXT WEEK.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 4 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
542 AM CST Fri Jan 30 2015
.SHORT TERM...(Today)
ISSUED AT 329 AM CST FRI JAN 30 2015
High pressure will build across central and southeast Illinois today
from the northwest. This Canadian high will bring cooler air into
the area than yesterday, but the fact that winds will be much
lighter and at least partly sunny skies are anticipated should make
for a decent late January day. The only real wild card today from
what should be a quiet weather day is how much cloud cover there
will be. Skies across the area are rapidly clearing from the
northwest as the high builds in, but there are still significant
patches of clouds upstream beneath the ridge axis across the upper
Midwest. For now, plan to be optimistic with cloud cover given the
clearing that has taken place so far, and the fact that forecast
soundings do not suggest significant low level moisture trapped
beneath the subsidence inversion.
&&
.LONG TERM...(Tonight through Thursday)
ISSUED AT 329 AM CST FRI JAN 30 2015
00Z Jan 30th forecast model suite continues to trend further north
with ECMWF model the further north and much further north than its
model runs a few runs ago. Consensus of models has heaviest snow
band to set up over our northern counties north of a Springfield to
Paris line during Saturday night and Sunday where 6-8 inches of snow
and locally higher amounts possible. Between 3-5 inches of snow
south of I-70 in southeast IL where mix precipitation to occur Sat
afternoon/evening before changing to all snow by overnight Sat night
into Sunday. Will issue another SPS to address the potential of several
inches of snow accumulations Saturday night and Sunday especially
from I-72 north. A winter storm watch may eventually be needed
Saturday night and Sunday especially over northern counties.
1037 mb high pressure over MN into the central plains will drift
east into the Ohio river valley by midnight tonight and into the mid
Atlantic States Sat morning and continue dry weather over central
and eastern IL. Lows tonight mostly in the lower 20s with a few
upper teens from Champaign and Paris northeast.
Low pressure organizing in the sw states to deepen surface low
pressure ne into the central Ohio river valley by sunset Sunday.
This to spread mixed precipitation into central IL during Sat
afternoon with areas from Lincoln south mainly light rain and mix of
light rain/snow northern counties with little or no snow
accumulations during daytime hours Sat. Highs Sat in the lower 40s,
with upper 30s from I-74 north. Brunt of snow and moderate at times
to develop during Saturday night into Sunday with mix of rain/snow
sw counties Sat evening. Models have trended heavier with qpf close
to three quarter inches and snowfall amounts especially north of
I-70. NE winds to veer north and increase during day Sunday from nw
to se and temperatures will likely be slipping Sunday especially in
afternoon with some blowing snow developing by Sunday afternoon into
Sunday evening. Light snow to diminish from the west during Sunday
night as low pressure pulls away from IL.
Canadian high pressure drifts down into IL from western Canadian Rockies
by Monday afternoon returning dry but cold weather as skies become
partly to mostly sunny. Highs Monday only in upper teens and lower
20s Monday due to expected snow pack. Temps briefly climb Tue into
low to mid 30s with breezy ssw winds ahead of clipper system that
moves into Great Lakes region Tue night and swings a cold front se
through IL Wed bringing chances of light snow and flurries. Even
colder air to follow this weather system for from Wed night through
Friday with lows possibly getting below zero Thu night after highs
Thu in mid to upper teens over central IL with lower 20s south of
I-70.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 542 AM CST FRI JAN 30 2015
Mainly quiet/VFR aviation weather conditions expected across the
central Illinois terminals through the 12Z TAF valid time. Skies
have become mostly clear across much of the area in the past few
hours, and cloud cover through the remainder of the period is
expected to remain minimal. However, will have to monitor some of
the MVFR cigs that still exist upstream across the upper Midwest
and see if any of them can hold together as they stream this way.
Northwest winds will diminish early this morning, becoming
light/variable as high pressure builds into the area. Winds are
then expected to trend southerly tonight as the high pressure
ridge pushes east of the area.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Bak
LONG TERM...07
AVIATION...Bak
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
542 AM CST Fri Jan 30 2015
.SHORT TERM...(Today)
ISSUED AT 329 AM CST FRI JAN 30 2015
High pressure will build across central and southeast Illinois today
from the northwest. This Canadian high will bring cooler air into
the area than yesterday, but the fact that winds will be much
lighter and at least partly sunny skies are anticipated should make
for a decent late January day. The only real wild card today from
what should be a quiet weather day is how much cloud cover there
will be. Skies across the area are rapidly clearing from the
northwest as the high builds in, but there are still significant
patches of clouds upstream beneath the ridge axis across the upper
Midwest. For now, plan to be optimistic with cloud cover given the
clearing that has taken place so far, and the fact that forecast
soundings do not suggest significant low level moisture trapped
beneath the subsidence inversion.
&&
.LONG TERM...(Tonight through Thursday)
ISSUED AT 329 AM CST FRI JAN 30 2015
00Z Jan 30th forecast model suite continues to trend further north
with ECMWF model the further north and much further north than its
model runs a few runs ago. Consensus of models has heaviest snow
band to set up over our northern counties north of a Springfield to
Paris line during Saturday night and Sunday where 6-8 inches of snow
and locally higher amounts possible. Between 3-5 inches of snow
south of I-70 in southeast IL where mix precipitation to occur Sat
afternoon/evening before changing to all snow by overnight Sat night
into Sunday. Will issue another SPS to address the potential of several
inches of snow accumulations Saturday night and Sunday especially
from I-72 north. A winter storm watch may eventually be needed
Saturday night and Sunday especially over northern counties.
1037 mb high pressure over MN into the central plains will drift
east into the Ohio river valley by midnight tonight and into the mid
Atlantic States Sat morning and continue dry weather over central
and eastern IL. Lows tonight mostly in the lower 20s with a few
upper teens from Champaign and Paris northeast.
Low pressure organizing in the sw states to deepen surface low
pressure ne into the central Ohio river valley by sunset Sunday.
This to spread mixed precipitation into central IL during Sat
afternoon with areas from Lincoln south mainly light rain and mix of
light rain/snow northern counties with little or no snow
accumulations during daytime hours Sat. Highs Sat in the lower 40s,
with upper 30s from I-74 north. Brunt of snow and moderate at times
to develop during Saturday night into Sunday with mix of rain/snow
sw counties Sat evening. Models have trended heavier with qpf close
to three quarter inches and snowfall amounts especially north of
I-70. NE winds to veer north and increase during day Sunday from nw
to se and temperatures will likely be slipping Sunday especially in
afternoon with some blowing snow developing by Sunday afternoon into
Sunday evening. Light snow to diminish from the west during Sunday
night as low pressure pulls away from IL.
Canadian high pressure drifts down into IL from western Canadian Rockies
by Monday afternoon returning dry but cold weather as skies become
partly to mostly sunny. Highs Monday only in upper teens and lower
20s Monday due to expected snow pack. Temps briefly climb Tue into
low to mid 30s with breezy ssw winds ahead of clipper system that
moves into Great Lakes region Tue night and swings a cold front se
through IL Wed bringing chances of light snow and flurries. Even
colder air to follow this weather system for from Wed night through
Friday with lows possibly getting below zero Thu night after highs
Thu in mid to upper teens over central IL with lower 20s south of
I-70.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 542 AM CST FRI JAN 30 2015
Mainly quiet/VFR aviation weather conditions expected across the
central Illinois terminals through the 12Z TAF valid time. Skies
have become mostly clear across much of the area in the past few
hours, and cloud cover through the remainder of the period is
expected to remain minimal. However, will have to monitor some of
the MVFR cigs that still exist upstream across the upper Midwest
and see if any of them can hold together as they stream this way.
Northwest winds will diminish early this morning, becoming
light/variable as high pressure builds into the area. Winds are
then expected to trend southerly tonight as the high pressure
ridge pushes east of the area.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Bak
LONG TERM...07
AVIATION...Bak
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
542 AM CST Fri Jan 30 2015
.SHORT TERM...(Today)
ISSUED AT 329 AM CST FRI JAN 30 2015
High pressure will build across central and southeast Illinois today
from the northwest. This Canadian high will bring cooler air into
the area than yesterday, but the fact that winds will be much
lighter and at least partly sunny skies are anticipated should make
for a decent late January day. The only real wild card today from
what should be a quiet weather day is how much cloud cover there
will be. Skies across the area are rapidly clearing from the
northwest as the high builds in, but there are still significant
patches of clouds upstream beneath the ridge axis across the upper
Midwest. For now, plan to be optimistic with cloud cover given the
clearing that has taken place so far, and the fact that forecast
soundings do not suggest significant low level moisture trapped
beneath the subsidence inversion.
&&
.LONG TERM...(Tonight through Thursday)
ISSUED AT 329 AM CST FRI JAN 30 2015
00Z Jan 30th forecast model suite continues to trend further north
with ECMWF model the further north and much further north than its
model runs a few runs ago. Consensus of models has heaviest snow
band to set up over our northern counties north of a Springfield to
Paris line during Saturday night and Sunday where 6-8 inches of snow
and locally higher amounts possible. Between 3-5 inches of snow
south of I-70 in southeast IL where mix precipitation to occur Sat
afternoon/evening before changing to all snow by overnight Sat night
into Sunday. Will issue another SPS to address the potential of several
inches of snow accumulations Saturday night and Sunday especially
from I-72 north. A winter storm watch may eventually be needed
Saturday night and Sunday especially over northern counties.
1037 mb high pressure over MN into the central plains will drift
east into the Ohio river valley by midnight tonight and into the mid
Atlantic States Sat morning and continue dry weather over central
and eastern IL. Lows tonight mostly in the lower 20s with a few
upper teens from Champaign and Paris northeast.
Low pressure organizing in the sw states to deepen surface low
pressure ne into the central Ohio river valley by sunset Sunday.
This to spread mixed precipitation into central IL during Sat
afternoon with areas from Lincoln south mainly light rain and mix of
light rain/snow northern counties with little or no snow
accumulations during daytime hours Sat. Highs Sat in the lower 40s,
with upper 30s from I-74 north. Brunt of snow and moderate at times
to develop during Saturday night into Sunday with mix of rain/snow
sw counties Sat evening. Models have trended heavier with qpf close
to three quarter inches and snowfall amounts especially north of
I-70. NE winds to veer north and increase during day Sunday from nw
to se and temperatures will likely be slipping Sunday especially in
afternoon with some blowing snow developing by Sunday afternoon into
Sunday evening. Light snow to diminish from the west during Sunday
night as low pressure pulls away from IL.
Canadian high pressure drifts down into IL from western Canadian Rockies
by Monday afternoon returning dry but cold weather as skies become
partly to mostly sunny. Highs Monday only in upper teens and lower
20s Monday due to expected snow pack. Temps briefly climb Tue into
low to mid 30s with breezy ssw winds ahead of clipper system that
moves into Great Lakes region Tue night and swings a cold front se
through IL Wed bringing chances of light snow and flurries. Even
colder air to follow this weather system for from Wed night through
Friday with lows possibly getting below zero Thu night after highs
Thu in mid to upper teens over central IL with lower 20s south of
I-70.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 542 AM CST FRI JAN 30 2015
Mainly quiet/VFR aviation weather conditions expected across the
central Illinois terminals through the 12Z TAF valid time. Skies
have become mostly clear across much of the area in the past few
hours, and cloud cover through the remainder of the period is
expected to remain minimal. However, will have to monitor some of
the MVFR cigs that still exist upstream across the upper Midwest
and see if any of them can hold together as they stream this way.
Northwest winds will diminish early this morning, becoming
light/variable as high pressure builds into the area. Winds are
then expected to trend southerly tonight as the high pressure
ridge pushes east of the area.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Bak
LONG TERM...07
AVIATION...Bak
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
542 AM CST Fri Jan 30 2015
.SHORT TERM...(Today)
ISSUED AT 329 AM CST FRI JAN 30 2015
High pressure will build across central and southeast Illinois today
from the northwest. This Canadian high will bring cooler air into
the area than yesterday, but the fact that winds will be much
lighter and at least partly sunny skies are anticipated should make
for a decent late January day. The only real wild card today from
what should be a quiet weather day is how much cloud cover there
will be. Skies across the area are rapidly clearing from the
northwest as the high builds in, but there are still significant
patches of clouds upstream beneath the ridge axis across the upper
Midwest. For now, plan to be optimistic with cloud cover given the
clearing that has taken place so far, and the fact that forecast
soundings do not suggest significant low level moisture trapped
beneath the subsidence inversion.
&&
.LONG TERM...(Tonight through Thursday)
ISSUED AT 329 AM CST FRI JAN 30 2015
00Z Jan 30th forecast model suite continues to trend further north
with ECMWF model the further north and much further north than its
model runs a few runs ago. Consensus of models has heaviest snow
band to set up over our northern counties north of a Springfield to
Paris line during Saturday night and Sunday where 6-8 inches of snow
and locally higher amounts possible. Between 3-5 inches of snow
south of I-70 in southeast IL where mix precipitation to occur Sat
afternoon/evening before changing to all snow by overnight Sat night
into Sunday. Will issue another SPS to address the potential of several
inches of snow accumulations Saturday night and Sunday especially
from I-72 north. A winter storm watch may eventually be needed
Saturday night and Sunday especially over northern counties.
1037 mb high pressure over MN into the central plains will drift
east into the Ohio river valley by midnight tonight and into the mid
Atlantic States Sat morning and continue dry weather over central
and eastern IL. Lows tonight mostly in the lower 20s with a few
upper teens from Champaign and Paris northeast.
Low pressure organizing in the sw states to deepen surface low
pressure ne into the central Ohio river valley by sunset Sunday.
This to spread mixed precipitation into central IL during Sat
afternoon with areas from Lincoln south mainly light rain and mix of
light rain/snow northern counties with little or no snow
accumulations during daytime hours Sat. Highs Sat in the lower 40s,
with upper 30s from I-74 north. Brunt of snow and moderate at times
to develop during Saturday night into Sunday with mix of rain/snow
sw counties Sat evening. Models have trended heavier with qpf close
to three quarter inches and snowfall amounts especially north of
I-70. NE winds to veer north and increase during day Sunday from nw
to se and temperatures will likely be slipping Sunday especially in
afternoon with some blowing snow developing by Sunday afternoon into
Sunday evening. Light snow to diminish from the west during Sunday
night as low pressure pulls away from IL.
Canadian high pressure drifts down into IL from western Canadian Rockies
by Monday afternoon returning dry but cold weather as skies become
partly to mostly sunny. Highs Monday only in upper teens and lower
20s Monday due to expected snow pack. Temps briefly climb Tue into
low to mid 30s with breezy ssw winds ahead of clipper system that
moves into Great Lakes region Tue night and swings a cold front se
through IL Wed bringing chances of light snow and flurries. Even
colder air to follow this weather system for from Wed night through
Friday with lows possibly getting below zero Thu night after highs
Thu in mid to upper teens over central IL with lower 20s south of
I-70.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 542 AM CST FRI JAN 30 2015
Mainly quiet/VFR aviation weather conditions expected across the
central Illinois terminals through the 12Z TAF valid time. Skies
have become mostly clear across much of the area in the past few
hours, and cloud cover through the remainder of the period is
expected to remain minimal. However, will have to monitor some of
the MVFR cigs that still exist upstream across the upper Midwest
and see if any of them can hold together as they stream this way.
Northwest winds will diminish early this morning, becoming
light/variable as high pressure builds into the area. Winds are
then expected to trend southerly tonight as the high pressure
ridge pushes east of the area.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Bak
LONG TERM...07
AVIATION...Bak
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
329 AM CST Fri Jan 30 2015
.SHORT TERM...(Today)
ISSUED AT 329 AM CST FRI JAN 30 2015
High pressure will build across central and southeast Illinois today
from the northwest. This Canadian high will bring cooler air into
the area than yesterday, but the fact that winds will be much
lighter and at least partly sunny skies are anticipated should make
for a decent late January day. The only real wild card today from
what should be a quiet weather day is how much cloud cover there
will be. Skies across the area are rapidly clearing from the
northwest as the high builds in, but there are still significant
patches of clouds upstream beneath the ridge axis across the upper
Midwest. For now, plan to be optimistic with cloud cover given the
clearing that has taken place so far, and the fact that forecast
soundings do not suggest significant low level moisture trapped
beneath the subsidence inversion.
&&
.LONG TERM...(Tonight through Thursday)
ISSUED AT 329 AM CST FRI JAN 30 2015
00Z Jan 30th forecast model suite continues to trend further north
with ECMWF model the further north and much further north than its
model runs a few runs ago. Concensus of models has heaviest snow
band to set up over our northern counties north of a Springfield to
Paris line during Saturday night and Sunday where 6-8 inches of snow
and locally higher amounts possible. Between 3-5 inches of snow
south of I-70 in southeast IL where mix precipitation to occur Sat
afternoon/evening before changing to all snow by overnight Sat night
into Sunday. Will issue another SPS to address the potential of several
inches of snow accumulations Saturday night and Sunday especially
from I-72 north. A winter storm watch may eventually be needed
Saturday night and Sunday especially over northern counties.
1037 mb high pressure over MN into the central plains will drift
east into the Ohio river valley by midnight tonight and into the mid
Atlantic States Sat morning and continue dry weather over central
and eastern IL. Lows tonight mostly in the lower 20s with a few
upper teens from Champaign and Paris northeast.
Low pressure organizing in the sw states to deepen surface low
pressure ne into the central Ohio river valley by sunset Sunday.
This to spread mixed precipitation into central IL during Sat
afternoon with areas from Lincoln south mainly light rain and mix of
light rain/snow northern counties with little or no snow
accumulations during daytime hours Sat. Highs Sat in the lower 40s,
with upper 30s from I-74 north. Brunt of snow and moderate at times
to develop during Saturday night into Sunday with mix of rain/snow
sw counties Sat evening. Models have trended heavier with qpf close
to three quarter inches and snowfall amounts especially north of
I-70. NE winds to veer north and increase during day Sunday from nw
to se and temperatures will likely be slipping Sunday especially in
afternoon with some blowing snow developing by Sunday afternoon into
Sunday evening. Light snow to diminish from the west during Sunday
night as low pressure pulls away from IL.
Canadian high pressure drifts down into IL from western Canadian Rockies
by Monday afternoon returning dry but cold weather as skies become
partly to mostly sunny. Highs Monday only in upper teens and lower
20s Monday due to expected snow pack. Temps briefly climb Tue into
low to mid 30s with breezy ssw winds ahead of clipper system that
moves into Great Lakes region Tue night and swings a cold front se
through IL Wed bringing chances of light snow and flurries. Even
colder air to follow this weather system for from Wed night through
Friday with lows possibly getting below zero Thu night after highs
Thu in mid to upper teens over central IL with lower 20s south of
I-70.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday night)
ISSUED AT 1135 PM CST THU JAN 29 2015
Overcast conditions remain in place across central Illinois late
this evening, although ceilings have improved into the VFR
category at all terminals. Satellite imagery continues to show
clearing across Iowa/Missouri working its way southeastward. Based
on satellite loops and the latest HRRR forecast, it appears skies
will begin to clear at KPIA by 08z, then further east to KCMI by
around 12z. Winds will remain gusty from the northwest early in
the period, but will drop to less than 10kt toward dawn, then will
go light/variable on Friday as high pressure builds into the area.
Once the overnight cloud cover departs, only SCT mid/high clouds
will be noted through 06z Sat.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Bak
LONG TERM...07
AVIATION...Barnes
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
228 AM CST FRI JAN 30 2015
.SHORT TERM...
234 PM CST
THROUGH SATURDAY...
THE MAIN FOCUS DURING THIS PERIOD WILL BE WITH THE POTENTIAL FOR
SOME ACCUMULATING LAKE EFFECT SNOW ACROSS PORTIONS OF NORTHWESTERN
INDIANA TONIGHT INTO FRIDAY MORNING.
LOW PRESSURE NOW ACROSS THE EASTERN GREAT LAKES REGION...DROVE A
COLD FRONT ACROSS THE AREA THIS MORNING...AND HAS SINCE CONTINUED TO
PRODUCING GUSTY NORTHWEST WINDS ACROSS THE REGION THROUGH THE
AFTERNOON. WATER VAPOR IMAGERY THIS AFTERNOON INDICATES THE NEXT
SHORT WAVE DISTURBANCE NOW DIGGING SOUTHWARD OVER LAKE SUPERIOR.
THIS DISTURBANCE IS EXPECTED TO RACE SOUTHWARD ACROSS SOUTHERN LAKE
MICHIGAN THIS EVENING...AND AS IT DOES SO...IT COULD PRODUCE ENOUGH
LIFT TO SQUEEZE OUT A FEW FLURRIES...SO I HAVE ADDED THE MENTION TO
THE FORECAST THROUGH MUCH OF THE EVENING.
OTHERWISE...IT APPEARS THAT LAKE EFFECT SNOW SHOWERS WILL CONTINUE
TO DEVELOP OVER SOUTHERN LAKE MICHIGAN TONIGHT...AND AS THE BOUNDARY
LAYER FLOW OVER LAKE MICHIGAN BEGINS TO BACK NORTHERLY...IT APPEARS
THAT SOME BANDS OF LAKE EFFECT SNOW WILL BEGIN TO IMPACT PORTIONS OF
NORTHWESTERN INDIANA OVERNIGHT TONIGHT THROUGH FRIDAY MORNING. LAKE
INDUCED EQUILIBRIUM LEVELS ARE EXPECTED TO RESIDE AROUND 5,000
FEET...AND DUE TO THE COLD LOWER LEVEL ATMOSPHERE...THIS SHOULD BE
HIGH ENOUGH TO RESIDE WELL INTO THE DENDRITE GROWTH ZONE.
THEREFORE...SOME EFFICIENT SNOWFALL LOOKS TO RESULT IN SOME
ACCUMULATING POTENTIAL...ESPECIALLY ACROSS PORTIONS OF PORTER COUNTY
INDIANA IN MY AREA...WHERE SOME ISOLATED AREAS COULD GET A COUPLE
INCHES. THESE LAKE EFFECT SNOW SHOWERS WILL COME TO AN END BY EARLY
AFTERNOON AS THE FLOW BEGINS TO SHIFT WESTERLY IN RESPONSE TO A AN
AREA OF SURFACE HIGH SHIFTING SOUTHEASTWARD TOWARDS THE OHIO
VALLEY.
A BRIEF WARMING TREND LOOKS TO BE ON TAP LATE FRIDAY NIGHT AND
SATURDAY AS THIS HIGH SHIFTS OVER THE OHIO VALLEY...SETTING UP A
WEST SOUTHWESTERLY FLOW OF WARMER AIR OVER THE AREA. THIS SHOULD
ALLOW TEMPERATURES TO WARM WELL INTO THE 30S AREA-WIDE.
KJB
&&
.LONG TERM...
328 PM CST
SATURDAY NIGHT THROUGH THURSDAY...
THE MAIN FOCUS DURING THIS PERIOD WILL BE WITH THE INCREASING
POTENTIAL OF A DECENT ACCUMULATING SNOWFALL EVENT ACROSS AT LEAST
PORTIONS OF MY AREA SATURDAY EVENING THROUGH SUNDAY.
A COMPLEX WEATHER PATTERN WILL BE IN PLACE ACROSS THE CONUS DURING
THIS PERIOD. OVERALL...THE MAIN DISTURBANCE OF INTEREST IS NOW
EJECTING EAST-NORTHEASTWARD ACROSS THE NORTHEASTERN PACIFIC ALONG
THE EASTERN PERIPHERY OF AN UPPER LOW SOUTH OF THE ALEUTIANS. THIS
FEATURE WILL MOVING ONSHORE ACROSS THE BRITISH COLUMBIA COAST BY
FRIDAY MORNING...THEN IS EXPECTED TO DIG SOUTHEASTWARD ALONG THE
NORTHEASTERN PERIPHERY OF AN UPPER LEVEL RIDGE IN PLACE ACROSS THE
WESTERN CONUS. THE MAIN COMPLEXITIES WITH THIS SYSTEM...IS IF AND
HOW MUCH OF THE SOUTHERN STREAM ENERGY...EMANATING FROM THE
SOUTHWESTERN CONUS TROUGH...GETS TAPPED INTO BY THIS DIGGING SYSTEM.
MODEL GUIDANCE HAS FLIPPED FLOPPED A BIT OVER THE PAST COUPLE OF
RUNS ON HOW FAR NORTH THE ACCOMPANYING PRECIPITATION SHIELD WILL GET
SATURDAY NIGHT INTO SUNDAY. IT APPEARS ONE OF THE MAIN KEYS THAT
WILL PLAY A ROLE IN HOW FAR NORTH THE SNOWFALL ENDS UP GETTING
ACROSS ILLINOIS WILL BE THE TIMING OF COLDER AIRMASS/COLD FRONTAL
PASSAGE EXPECTED ON SATURDAY NIGHT. A MUCH COLDER AIRMASS IS
EXPECTED TO SPILL IN ACROSS THE NORTHERN CONUS AHEAD OF A STOUT 1044
MB HIGH BUILDING SOUTHWARD OUT OF SOUTHERN MANITOBA SATURDAY
NIGHT...AND THIS SHOULD SET UP A GOOD BAROCLINIC ZONE POTENTIALLY
RIGHT ACROSS THE HEART OF MY CWA SATURDAY NIGHT INTO SUNDAY. AT THE
SAME TIME...ISENTROPIC ASCENT AND MOISTURE TRANSPORT WILL RAMP UP TO
OUR SOUTHWEST IN ADVANCE OF THE APPROACHING DISTURBANCE. THIS SHOULD
RESULT IN A LARGE AREA OF SNOWFALL DEVELOPMENT IN THE COLD AIR ACROSS
MISSOURI AND WEST CENTRAL ILLINOIS BY SATURDAY AFTERNOON. IT APPEARS
THIS SNOWFALL WILL GRADUALLY DEVELOP NORTHWARD ACROSS ILLINOIS BY
SATURDAY EVENING...AND MAY END UP IMPACTING MOST OF MY AREA TO SOME
DEGREE OVERNIGHT SATURDAY AND INTO SUNDAY. IT APPEARS THAT A DECENT
BAND OF FRONTOGENESIS COULD SET UP SOMEWHERE NEAR THE I-80 CORRIDOR
INTO SUNDAY MORNING AS A DEFORMATION AXIS TRIES TO DEVELOP WITH THE
925-850 MB LAYER AHEAD OF THE APPROACHING COLD AIRMASS. THIS COULD
RESULT IN SOME AREAS OF HEAVIER SNOW. HOWEVER...CONFIDENCE ON WHERE
EXACTLY THIS ENHANCED MESOSCALE FORCING SETS UP IS LOW AT THIS
TIME...GIVEN THIS SYSTEM IS 60+ HOURS AWAY. IT DOES APPEAR THAT MOST
AREAS MAY SEE AT LEAST SOME LIGHT SNOW ACCUMULATIONS...BUT THE
POTENTIAL OF A FEW TO SEVERAL INCHES OF SNOW ACCUMULATION IS
CERTAINLY A POSSIBILITY.
THE OTHER FACTOR TO CONSIDER WITH THIS EVENT IS THE POTENTIAL FOR
LAKE ENHANCED SNOW SHOWERS LATER SUNDAY AND INTO SUNDAY NIGHT ACROSS
NORTHEASTERN ILLINOIS. AS THE COLDER AIRMASS BEGINS TO SPILL
SOUTHWARD OVER THE AREA ON SUNDAY...WINDS WILL BECOME NORTHEASTERLY
OFF OF LAKE MICHIGAN. THE COLDER AIRMASS...FEATURING 850 MB
TEMPERATURES IN THE TEENS BELOW ZERO CELSIUS...SHOULD ALSO PRODUCE
FAVORABLE THERMODYNAMICS IN THE LOWEST LEVELS OF THE ATMOSPHERE FOR
ENHANCED SNOW SHOWERS LATER SUNDAY AND SUNDAY NIGHT. MODEL SOUNDINGS
INDICATE INVERSION HEIGHTS REACHING UP AROUND 5-6,000 FEET...WHICH
SHOULD EXTEND WELL INTO THE DENDRITIC GROWTH ZONE. THEREFORE...WE CANT
RULE OUT THE POTENTIAL FOR SOME HEAVIER SNOW TOTALS ACROSS PORTIONS
OF NORTHEASTERN ILLINOIS. AT THIS TIME...I HAVE REMAINED A BIT
CONSERVATIVE ON SNOW AMOUNTS ACROSS NORTHERN ILLINOIS...MAINLY DUE
TO THE HIGH UNCERTAINTIES WITH THIS EVOLVING SYSTEM.
FOLLOWING THIS SYSTEM...IT APPEARS THE REGION WILL REMAIN IN AND
ACTIVE WEST/NORTHWESTERLY FLOW PATTERN. THIS COULD SUPPORT A FEW
ADDITIONAL CLIPPER TYPE SYSTEMS WITH SNOW CHANCES AND REINFORCING
SHOTS OF COLD AIR THROUGH THE EXTENDED PERIOD. OVERALL...IT APPEARS
THAT WE WILL REMAIN BELOW TO WELL BELOW AVERAGE FOR TEMPERATURES
NEXT WEEK. A PERIOD OF VERY COLD CONDITIONS COULD ALSO BE IN THE
WORKS FOR THE LATTER PART OF NEXT WEEK...WITH THE POSSIBILITIES OF A
SYSTEM DIGGING SOUTHWARD OVER THE AREA FROM THE HIGH LATITUDES OF
CANADA.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* GUSTY NORTHWEST WINDS THROUGH EARLY THIS MORNING BACKING TO
SOUTHWEST THIS AFTERNOON.
KREIN
//DISCUSSION...UPDATED 06Z...
COLD AIR ADVECTION AND A WEAK UPPER DISTURBANCE WILL WORK IN
CONCERT TO PRODUCE SOME FLURRIES AND BRIEF LIGHT SNOW SHOWERS
OVERNIGHT...LIKELY ENDING PRIOR TO SUNRISE. HAVE SEEN A FEW BRIEF
VSBY REDUCTIONS IN THE SNOW SHOWERS IN SE WISCONSIN AND CERTAINLY
POSSIBLE THE SAME COULD OCCUR INTO OUR TERMINALS...THOUGH ANY
VSBY RESTRICTIONS WILL LIKELY BE SHORT LIVED. LOWER END VFR CIGS
SHOULD SCATTER OUT AT SOME POINT FRIDAY MORNING AND NOT
ANTICIPATING ANY MVFR CIGS THROUGH THE PERIOD. NORTHWEST WINDS
WILL GRADUALLY EASE THROUGH THE MORNING HOURS BEFORE GRADUALLY
BACK TO SOUTHWEST FRIDAY AFTERNOON INTO EARLY EVENING BUT WITH
VERY LIGHT SPEEDS.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* MEDIUM TO HIGH CONFIDENCE WIND TRENDS.
* MEDIUM CONFIDENCE IN CLOUD COVER TRENDS.
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS
KREIN
//OUTLOOK FOR ORD/MDW FOR 12Z SATURDAY-12Z THURSDAY...UPDATED 00Z...
SATURDAY...CHANCE OF SNOW AND IFR DURING THE NIGHT. WEST WINDS.
SUNDAY...CHANCE OF SNOW AND IFR. AT LEAST MVFR CIGS LIKELY.
NORTHEAST WINDS.
MONDAY NIGHT-WEDNESDAY...CHANCES OF MAINLY LIGHT SNOW. WEST WINDS.
MDB
&&
.MARINE...
230 AM CST
A PROGRESSIVE...ACTIVE PATTERN WILL CONTINUE FOR LAKE MICHIGAN FOR
THE NEXT SEVERAL DAYS. WINDS ARE SLOWLY DIMINISHING OVER THE LAKE
AND WILL LET THE GALE AND HEAVY FREEZING SPRAY WARNINGS EXPIRE AT
300 AM. HOWEVER...WITH LAKE MICHIGAN STILL UNDER A RELATIVELY
STRONG PRESSURE GRADIENT...A SMALL CRAFT ADVISORY WILL BE ISSUED
FOR BOTH THE ILLINOIS NEARSHORE WATERS AS WINDS ARE STILL ARND 30
KT EARLY THIS MORNING...BUT SHOULD DROP OFF TO 10-15KT BY MID DAY.
RESIDUAL WAVE ACTION FROM THE PERSISTENT NORTHERLY WINDS SHOULD
KEEP WAVES ABOVE 4 FT THROUGH THIS AFTERNOON. AS THE AXIS OF HIGH
PRESSURE MOVES ACROSS THE LAKE THIS EVENING A BRIEF PERIOD OF
RELATIVELY MILD CONDITONS WILL SET UP...BUT THE HIGH WILL QUICKLY
SETTLE INTO THE OHIO VALLEY TONIGHT AS LOW PRESSURE TRACKS ACROSS
THE UPPER GREAT LAKES REGION. THIS SYSTEM WILL DRAG A COLD FRONT
ACROSS THE LAKE SATURDAY. FOLLOWING THE PASSAGE OF THE COLD
FRONT...STRONG HIGH PRESSURE WILL BUILD ACROSS THE CNTRL PLAINS
AND UPPER GREAT LAKES SATUDAY NIGHT AND SUNDAY WHILE LOW PRESSURE
DEVELOPS OVER THE LOWER OHIO VALLEY SUNDAY AFTERNOON. AN EXTENDED
PERIOD OF NELY WINDS OF 25-30 KT WILL BEGIN FOLLOWING THE FRONTAL
PASSAGE AND PERSIST INTO EARLY NEXT WEEK.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 3 AM FRIDAY.
SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 4 PM FRIDAY.
HEAVY FREEZING SPRAY WARNING...LMZ261-LMZ362-LMZ364-LMZ366-
LMZ563-LMZ565-LMZ567-LMZ868 UNTIL 3 AM FRIDAY.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1135 PM CST Thu Jan 29 2015
.UPDATE...
ISSUED AT 647 PM CST THU JAN 29 2015
Clouds continue to blanket central Illinois early this evening:
however, quite a bit of clearing is developing upstream across
Minnesota into far northern Iowa. This clearing is occurring within
the subsident region behind a short-wave trough noted on water
vapor imagery over Lake Superior/Wisconsin. As this wave tracks
into Michigan later tonight, the clearing will develop further
southeastward into portions of central Illinois after midnight.
HRRR continues to suggest a gradual dissipation of the cloud cover
overnight, while the NAM holds on to the clouds right through
Friday. Based on latest satellite loop, think the NAM is too
aggressive with its low-level moisture so will trend toward the
HRRR for the short-term forecast. Satellite timing tools continue
to indicate at least partial clearing arriving northwest of the
Illinois River by 06-07z, then further east and south across most
of the area by dawn. Some locations near the Indiana border and
along/south of I-70 may stay overcast until Friday morning. Have
updated sky grids to better reflect current and expected trends.
Have also updated hourly temps to slow the initial fall due to the
lingering cloud cover this evening. Once skies begin to clear,
temps will drop off steadily after midnight, with lows ranging
from the teens northwest of the Illinois River to the middle 20s
along/south of I-70 where clouds will persist longest.
&&
.SHORT TERM...(Tonight)
ISSUED AT 329 PM CST THU JAN 29 2015
Forecast challenge for tonight will be whether or not any partial
clearing will occur and the affect on low temperatures. The latest
satellite loop early this afternoon indicated an area of partly
cloudy skies in central/southern MN into central IA behind a
departing shortwave trough. This area was starting to fill in with a
few more clouds, though, the past hour. The latest guidance from the
RAP, HRRR and NAM all indicate that moisture in the lowest 100 mb
should stay high enough overnight for low clouds to persist until
Friday morning. Breaks in the clouds may occur at times late this
evening, but they shouldn`t low enough to impact low temperatures.
As a result will go with lows in the 20-25 range across all of
central and southeast IL.
Patches of drizzle/flurries may linger in parts of central Illinois
early this evening. However, this will have very small areal
coverage and will have little or no impact, so will not include in
the forecast for tonight.
As the low pressure center moves through the eastern Great Lakes
late this evening, the pressure gradient should loosen up, resulting
in gradually diminishing winds in central Illinois early tonight,
and in eastern Illinois by daybreak.
&&
.LONG TERM...(Friday through Thursday)
ISSUED AT 329 PM CST THU JAN 29 2015
Models have come into better agreement with the main focus for this
forecast, this weekend winter weather system. The GFS and ECMWF both
look very similar with location of the heaviest snowfall Sat night
through Sun. Only differences in the those two models is the timing
and track of the low press area as it moves northeast across the
southern Miss valley. Precip will begin to spread into the western
parts of the CWA Sat afternoon, but temps will be warm enough for
most of the pcpn to be either rain, or a mix of rain or snow. No
accumulations are expected during the afternoon due to the warm
temps. The major part of the snow will arrive late Sat night, after
midnight, through some light accumulations are possible Sat evening.
After midnight, the snow is expected to become moderate with rates
approaching 1/2 inch per hour. The snow will be during the
overrunning period of the system as it begins to lift out of the
southern plains. With the upper level part of the system being just
an open trough/wave, a heavy deformation area of snow will likely
not setup on the back side of the low pressure area. However, snow
will continue Sun afternoon through Sun evening, with accumulations
being on the lighter side. Preliminary indications are that snowfall
totals from Sat evening through Sun night will be in the 4.5 to 6
inch range. There is still some uncertainty with these amounts as
the models are just now coming into agreement and some shift south
or north with the track is still possible. Given the longer duration
of the snowfall, it does not meet criteria for a watch at this time,
so no headlines will be issued. A later forecast shift may decide to
issue one if any changes occur with the model forecasts.
Beyond this system this weekend, conditions will be relatively dry,
except for Tue night when another chance of snow is possible from a
system coming down from the northwest. Once this system pushes
through, temps will drop and become well below normal for Wed
through Thur.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday night)
ISSUED AT 1135 PM CST THU JAN 29 2015
Overcast conditions remain in place across central Illinois late
this evening, although ceilings have improved into the VFR
category at all terminals. Satellite imagery continues to show
clearing across Iowa/Missouri working its way southeastward. Based
on satellite loops and the latest HRRR forecast, it appears skies
will begin to clear at KPIA by 08z, then further east to KCMI by
around 12z. Winds will remain gusty from the northwest early in
the period, but will drop to less than 10kt toward dawn, then will
go light/variable on Friday as high pressure builds into the area.
Once the overnight cloud cover departs, only SCT mid/high clouds
will be noted through 06z Sat.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Miller
LONG TERM...Auten
AVIATION...Barnes
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1130 PM CST THU JAN 29 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 315 PM CST THU JAN 29 2015
MAIN FORECAST CONCERN DEALT WITH LINGERING STRATUS DECK
AND TEMPERATURES AS A RESULT OF THE LINGERING CLOUD COVER. LEANED
TOWARD THE NAM/RAP/HRRR FOR CLOUD COVER AND LOW LEVEL RH THIS
EVENING. SOUNDINGS SUGGEST THE INVERSION CONTINUES THROUGH FRIDAY
MORNING AND POTENTIALLY TRAPPING THE LOW LEVEL MOISTURE/STRATUS OVER
CENTRAL IOWA DURING MUCH OF THE NIGHT. THERE IS A DECENT BREAK IN
THE CLOUD DECK OVER NORTH-CENTRAL IOWA AND INTO SOUTHERN MINNESOTA
AS OF 21Z...AND THE HRRR HAS SOMEWHAT PICKED UP ON THIS TREND AND
SLOWLY ERODES THE STRATUS BY AROUND 05Z ACROSS IOWA/MINNESOTA. HAVE
STRATUS SLOWLY ERODING DURING THE EVENING HOURS WITH THE NORTHEAST
SLOWEST TO CLEAR OUT.
CAA CONTINUES THROUGHOUT MUCH OF THE NIGHT BEFORE THE SURFACE RIDGE
SLIDES INTO NORTHERN IOWA FRIDAY MORNING AND FINALLY ALLOWING THE
WINDS TO BECOME LIGHT AND VARIABLE. SO ANY RADIATIONAL COOLING WILL
BE CLOSER TO SUNRISE. WITH THE TEMPERATURES REMAINING FAIRLY COLD
THIS AFTERNOON...LEANED TOWARD THE RAP FOR LOWS TONIGHT AS IT SEEMED
TO HAVE A BETTER HANDLE ON TEMP AND CLOUD COVER TRENDS.
.LONG TERM /FRIDAY THROUGH THURSDAY/...
ISSUED AT 315 PM CST THU JAN 29 2015
MUCH OF THE LONG TERM FORECAST WILL BE DOMINATED BY BROAD
NORTHWEST FLOW AND A SERIES OF WAVES MOVING THROUGH THE FLOW.
SURFACE RIDGING WILL BE ACROSS THE STATE AT THE BEGINNING OF THE
LONGER TERM TOMORROW MORNING WITH FRIDAY BEING THE BEST DAY OUT OF
REMAINDER OF THE FORECAST. WARM ADVECTION WILL INCREASE BY LATER
IN THE DAY AS SOUTHERLY SURFACE FLOW RESUMES AND READINGS ONCE
AGAIN ABOVE NORMAL. A DECENT PRESSURE GRADIENT KEEPING WINDS UP ON
FRIDAY NIGHT ALONG WITH INCREASING CLOUDINESS WILL HELP KEEP
TEMPERATURES QUITE WARM OVERNIGHT. MAY BEGIN TO SEE SOME LIGHT
PRECIPITATION IN THE FAR SOUTHWEST TOWARD DAYBREAK BUT THE BULK OF
THE SYSTEM WILL COME IN LATER PERIODS.
MOVING INTO THE WEEKEND...ALL FOCUS SHIFTS TO A SHORTWAVE TOPPING
THE WESTERN RIDGE AND ITS INTERACTION WITH A VERY MOIST UPPER LOW
ACROSS THE SOUTHWEST UNITED STATES. THE 12Z MODELS ARE BEGINNING
TO CLUSTER AROUND A SOLUTION OF DROPPING THE NORTHERN SHORTWAVE
SOUTHEAST WITH SUFFICIENT AMPLITUDE TO BRING THE MOISTURE PLUME
FAR ENOUGH NORTH TO IMPACT IOWA...AT LEAST THE SOUTHERN HALF OR
SO. INITIALLY...A SHORTWAVE THAT PASSES THROUGH THE GREAT LAKES
AREA FRIDAY NIGHT WILL SEND A COLD FRONT SOUTHWARD THRU THE
FORECAST AREA ON SATURDAY. MEANWHILE..INCREASING ISENTROPIC LIFT
AND MOISTURE ADVECTION WILL LEAD TO PRECIPITATION DEVELOPMENT
ACROSS SOUTHERN IOWA ON SATURDAY MORNING AHEAD OF THE BOUNDARY.
THE PRECIPITATION WILL LIKELY BE RAIN IN FAR SOUTHERN IOWA WITH
TEMPERATURES IN THE MID TO UPPER 30S. HOWEVER...A TRANSITION TO
SNOW IS LIKELY BY I80 OR HWY30 AS COLDER AIR IS ENCOUNTERED WITH
THE SOUTHWARD MOVING BOUNDARY. FORCING WILL SUSTAIN AND INCREASE
INTO SATURDAY NIGHT WITH DECENT MID LEVEL FRONTOGENETICAL FORCING
ACROSS THE SOUTHERN IOWA. ANY RAIN IN THE SOUTH ON SATURDAY WILL
TRANSITION TO SNOW IN THE EVENING AS COLD AIR CONTINUES TO DEEPEN
AND SPREAD SOUTHWARD BEHIND THE BOUNDARY. BY LATE SATURDAY NIGHT
INTO SUNDAY...DECENT MID LEVEL FORCING FROM APPROACHING SOUTHEAST
MOVING SHORTWAVE WILL HELP SNOW TO CONTINUE DURING THE DAY.
EVENTUALLY...THE FORCING WILL SHIFT TO THE EAST BY LATE IN THE DAY
WITH THE SNOW ENDING. THERE WILL BE A TIGHT GRADIENT OF SNOWFALL
ON NORTHERN SIDE OF PRECIPITATION SHIELD AND THEREFORE THE SNOW
AMOUNTS THAT ACCOMPANY THIS SYSTEM. AT THIS POINT...THE GRADIENT
APPEARS NEAR THE I80 CORRIDOR ALTHOUGH THIS WILL LIKELY MOVE WITH
SUBSEQUENT INFORMATION. GIVEN THE LONG DURATION OF THIS EVENT...IT
DOESNT APPEAR WARNING CRITERIA WILL BE MET...ALTHOUGH THE
COMBINATION OF WINDS AND SNOW MAY BE ENOUGH TO BOOST US INTO
WARNING. GIVEN THE CHANGES IN MODEL RUNS OVER THE PAST 36
HOURS...WILL WAIT ON ANY HEADLINES BUT BEGIN TO HIGHLIGHT MORE IN
THE HWO AND OTHER PRODUCTS. AMOUNTS OF AROUND 6 INCHES SEEM
POSSIBLE NEAR THE MO BORDER WITH 2-5 IN CENTRAL IOWA...AND AN INCH
OR LESS ACROSS THE NORTH.
MUCH COLDER AIR WILL FILTER INTO THE STATE FOR NEXT WEEK WITH A
SERIES OF SHORTWAVES PASSING THROUGH THE REGION. THIS WILL BRING
THE THREAT OF SNOW MONDAY NIGHT INTO TUESDAY WITH REINFORCING
SHOTS OF COLDER AIR.
&&
.AVIATION...30/06Z
ISSUED AT 1130 PM CST THU JAN 29 2015
CIGS SCATTERING ACROSS CNTRL IA AND EXPECT VFR CONDITIONS AT ALL
SITES THOUGH MUCH OF THE PERIOD. KOTM WILL EXPERIENCE MVFR CIGS
INITIALLY THEN BECOME VFR BY 08Z. NORTHWEST WINDS WILL SWITCH TO
THE SOUTH TO SOUTHWEST ON FRIDAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...COGIL
AVIATION...DONAVON
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
308 PM CST FRI JAN 30 2015
...UPDATED LONG TERM...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 144 PM CST FRI JAN 30 2015
MOISTURE AND ISENTROPIC LIFT FROM I300 TO I308 APPEARS TO HAVE A
DECENT HANDLE OF THE LIGHT PRECIPITATION CURRENTLY SPREADING NORTH
ACROSS NORTHEAST NEW MEXICO AND THE PANHANDLE OF TEXAS. BASED ON
15Z AND 18Z VERIFICATION EARLIER TODAY WILL THEREFORE BE USING THE
THE I300 TO I308 LEVEL OVERNIGHT AS GUIDE FOR PRECIPITATION
CHANCES AND TIMING OF THIS PRECIPITATION AS IMPROVING MOISTURE
AND ISENTROPIC LIFT DEVELOPS ACROSS SOUTHWEST KANSAS. AT THIS TIME
BASED ON THE 12Z NAM AND LATEST RAP THE BETTER OPPORTUNITY FOR
WIDESPREAD PRECIPITATION OVER WESTERN KANSAS WILL BE FROM 03Z AND
09Z SATURDAY. AFTER 09Z ISENTROPIC DOWNGLIDE BEGINS TO DEVELOPS
ACROSS FAR WESTERN KANSAS SO THIS PRECIPITATION TO BEGIN TO TAPER
OFF NEAR THE COLORADO BORDER, OR AT LEAST BECOME MORE WIDELY
SCATTERED, EARLY FRIDAY MORNING.
AT THIS TIME MODEL SOUNDINGS ALONG WITH THE TOP DOWN APPROACH FOR
PRECIPITATION TYPE BOTH SUPPORT MAINLY A COLD RAIN EVENT FOR ALL
BUT PORTIONS OF NORTH CENTRAL AND FAR WESTERN KANSAS. IN THE NORTH
CENTRAL AND FAR WESTERN KANSAS THE ATMOSPHERE WILL BECOME COLD
ENOUGH FOR THE RAIN TO MIX WITH, OR BRIEFLY CHANGE OVER TO SNOW
AROUND DAYBREAK SATURDAY. BASED ON THE WARM SURFACE TEMPERATURES
AND RAINFALL OVERNIGHT LITTLE IF ANY SNOW ACCUMULATION IS EXPECTED
SHOULD A BRIEF PERIOD OF SNOW DEVELOPS.
AREAS OF FOG CAN ALSO BE EXPECTED LATE TONIGHT BASED ON THE
MOISTURE PROFILES NEAR THE SURFACE AND SOUTH SOUTHEASTERLY WIND AT
10 TO 15 MPH.
ON THURSDAY SOME BREAKS OF SUN WILL BE POSSIBLE ACROSS PORTIONS OF
WESTERN KANSAS EARLY IN THE DAY GIVEN THE ISENTROPIC DOWNGLIDE
DEVELOPING IN THIS AREA. AS A RESULT HAVE FAVORED THE WARMER
GUIDANCE FOR HIGHS SATURDAY AFTERNOON WEST OF HIGHWAY 283. FURTHER
EAST MOISTURE AND WEAK ISENTROPIC LIFT WILL CONTINUE SO WILL FAVOR
THE COOLER GUIDANCE GIVEN THE EXPECTED CLOUD COVER AND LIGHT
PRECIPITATION. AT THIS TIME HIGHS ARE EXPECTED TO VARY FROM NEAR
40 IN SOUTH CENTRAL KANSAS TO MID 40S IN WEST CENTRAL KANSAS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 307 PM CST FRI JAN 30 2015
CONFIDENCE REMAINS RELATIVELY HIGH THAT THE SYSTEM WILL BE TOO SLOW
TO TURN COLD ENOUGH TO WARRANT A SIGNIFICANT ACCUMULATION OF SNOW
SATURDAY NIGHT. THE LATEST NAM AND ECMWF RUNS MAINTAIN OUR AREA ON
THE WARM SIDE OF THE SURFACE BOUNDARY UNTIL MID EVENING SATURDAY
WHEN HE FRONT IS ABLE TO BE FORCED THROUGH THE CENTRAL HIGH PLAINS
BY THE EXITING UPPER SYSTEM. EVENT HE IMMEDIATE POST FRONTAL AIR
APPEARS TOO WARM FOR SNOW ACCUMULATION, AND TEMPERATURES MAY NOT
FALL COLD ENOUGH ACROSS A LARGE ENOUGH PORTION OF THE AREA UNTIL
SUNDAY MORNING WHEN THE UPPER STRETCHING AND DEFORMATION HAS
BASICALLY CEASED.
THE COLDEST AIR IN A FEW WEEKS SHOULD THEN BE NOTICED BY SUNDAY
NIGHT AND EARLY MONDAY MORNING, AS STRONG SUBSIDENCE, DRIER AIR AND
GOOD LONGWAVE RADIATIONAL COOLING OF A COLDER DRIER AIRMASS IS
POSSIBLE. THE MOS OUTPUT FROM AT LEAST THE ECMWF AND NAM MODELS ARE
THE COLDEST WITH POTENTIAL FOR EVEN SINGLE DIGITS OVER CENTRAL
KANSAS EARLY MONDAY MORNING. THE CONSENSUS OF RAW MODEL OUTPUT WAS
NOT FAR FROM THESE COLDER SOLUTION AS WELL, WHICH WAS USED AS THE
OFFICIAL FORECAST. A STRONG WARMING TREND ON THE EAST SIDE OF AN
UPPER RIDGE WILL BE NOTICED HEADING INTO MID WEEK, WITH TEMPERATURES
LIKELY BACK INTO THE 60S BEFORE THE NEXT UPPER JET/SHORTWAVE/COLD
FRONT AFFECT THE CENTRAL PLAINS LATE WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1120 AM CST FRI JAN 30 2015
NAM AND RAP WERE IN GOOD AGREEMENT TODAY WITH VFR CEILINGS
LOWERING THROUGH THE DAY AS ISENTROPIC LIFT AND MOISTURE ADVECTION
IMPROVE ACROSS WESTERN KANSAS. HRRR AND BUFR SOUNDINGS INDICATING
LOW VFR CEILINGS WILL DEVELOP AT GCK AND DDC AROUND 21Z FRIDAY AND
THEN CONTINUE TO LOWER WITH MVFR CONDITIONS DEVELOPING BETWEEN 00Z
AND 03Z SATURDAY AS SOME LIGHT RAIN DEVELOPS. AFTER 06Z CEILINGS
AND VISIBILITIES WILL FALL BACK INTO THE IFR CATEGORY AS THE
LOWER LEVELS SATURATES. AT HYS MVFR CEILINGS ARE EXPECTED TO
TOWARDS 06Z SATURDAY AND IFR CONDITIONS 12Z SATURDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 34 44 33 36 / 80 60 60 10
GCK 34 46 33 37 / 70 50 50 0
EHA 33 44 35 40 / 80 50 50 0
LBL 34 44 37 41 / 80 60 60 10
HYS 33 42 28 29 / 80 50 60 0
P28 36 42 38 38 / 80 70 70 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...RUSSELL
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
148 PM CST FRI JAN 30 2015
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 144 PM CST FRI JAN 30 2015
MOISTURE AND ISENTROPIC LIFT FROM I300 TO I308 APPEARS TO HAVE A
DECENT HANDLE OF THE LIGHT PRECIPITATION CURRENTLY SPREADING NORTH
ACROSS NORTHEAST NEW MEXICO AND THE PANHANDLE OF TEXAS. BASED ON
15Z AND 18Z VERIFICATION EARLIER TODAY WILL THEREFORE BE USING THE
THE I300 TO I308 LEVEL OVERNIGHT AS GUIDE FOR PRECIPITATION
CHANCES AND TIMING OF THIS PRECIPITATION AS IMPROVING MOISTURE
AND ISENTROPIC LIFT DEVELOPS ACROSS SOUTHWEST KANSAS. AT THIS TIME
BASED ON THE 12Z NAM AND LATEST RAP THE BETTER OPPORTUNITY FOR
WIDESPREAD PRECIPITATION OVER WESTERN KANSAS WILL BE FROM 03Z AND
09Z SATURDAY. AFTER 09Z ISENTROPIC DOWNGLIDE BEGINS TO DEVELOPS
ACROSS FAR WESTERN KANSAS SO THIS PRECIPITATION TO BEGIN TO TAPER
OFF NEAR THE COLORADO BORDER, OR AT LEAST BECOME MORE WIDELY
SCATTERED, EARLY FRIDAY MORNING.
AT THIS TIME MODEL SOUNDINGS ALONG WITH THE TOP DOWN APPROACH FOR
PRECIPITATION TYPE BOTH SUPPORT MAINLY A COLD RAIN EVENT FOR ALL
BUT PORTIONS OF NORTH CENTRAL AND FAR WESTERN KANSAS. IN THE NORTH
CENTRAL AND FAR WESTERN KANSAS THE ATMOSPHERE WILL BECOME COLD
ENOUGH FOR THE RAIN TO MIX WITH, OR BRIEFLY CHANGE OVER TO SNOW
AROUND DAYBREAK SATURDAY. BASED ON THE WARM SURFACE TEMPERATURES
AND RAINFALL OVERNIGHT LITTLE IF ANY SNOW ACCUMULATION IS EXPECTED
SHOULD A BRIEF PERIOD OF SNOW DEVELOPS.
AREAS OF FOG CAN ALSO BE EXPECTED LATE TONIGHT BASED ON THE
MOISTURE PROFILES NEAR THE SURFACE AND SOUTH SOUTHEASTERLY WIND AT
10 TO 15 MPH.
ON THURSDAY SOME BREAKS OF SUN WILL BE POSSIBLE ACROSS PORTIONS OF
WESTERN KANSAS EARLY IN THE DAY GIVEN THE ISENTROPIC DOWNGLIDE
DEVELOPING IN THIS AREA. AS A RESULT HAVE FAVORED THE WARMER
GUIDANCE FOR HIGHS SATURDAY AFTERNOON WEST OF HIGHWAY 283. FURTHER
EAST MOISTURE AND WEAK ISENTROPIC LIFT WILL CONTINUE SO WILL FAVOR
THE COOLER GUIDANCE GIVEN THE EXPECTED CLOUD COVER AND LIGHT
PRECIPITATION. AT THIS TIME HIGHS ARE EXPECTED TO VARY FROM NEAR
40 IN SOUTH CENTRAL KANSAS TO MID 40S IN WEST CENTRAL KANSAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 324 AM CST FRI JAN 30 2015
THE COLD FRONT COMING THROUGH THIS WEEKEND HAS SLOWED A LITTLE, AND
WILL NOT CLEAR OUR SOUTHERN BORDER UNTIL SUNDAY EVENING.
THEREFORE, THERE WILL LIKELY BE A PROLONGED PERIOD OF A RAIN/SNOW
MIXTURE INTO EARLY AFTERNOON SATURDAY. THEN THE SOUTHERLY FLOW IN
THE SOUTH WILL ALLOW FOR A CHANGE TO ALL LIGHT RAIN SATURDAY
AFTERNOON. HOWEVER, THE COLD AIR WILL SETTLE IN SATURDAY NIGHT AND
THE PRECIPITATION WILL GO BACK TO A RAIN/SNOW MIX SATURDAY NIGHT.
THIS WILL CONTINUE INTO SUNDAY MORNING AS AN UPPER TROUGH DRAGS
ACROSS THE PLAINS. PRECIPITATION CHANCES WILL BE HIGHEST IN THE
EASTERN CWA SATURDAY, AND DIMINISH ON SUNDAY AS THE SYSTEM CLEARS
TO THE EAST. SATURDAY SHOULD BE A LITTLE WARMER THAN PREVIOUSLY
THOUGHT, DUE TO THE SLOWING OF THE FRONT`S SOUTHWARD PROGRESSION.
HIGHS SHOULD TOP OUT IN THE LOWER 40S NORTH OF I-70, AND THE
MIDDLE 40S DOWN SOUTH ALONG THE OKLAHOMA BORDER. SUNDAY WILL BE
CONSIDERABLY COLDER WITH CLOUDS, EARLY PRECIP AND WIND SHIFTING
SHARPLY TO THE NORTH AND INCREASING INTO THE 18G28MPH RANGE.
MONDAY SHOULD SEE THE UPPER FLOW TRANSITION FROM A NORTHWEST TO A
MORE WESTERLY ZONAL FLOW. SURFACE CONDITIONS WILL START TO WARM
AND THE WESTERN EDGE OF KANSAS WILL REACH TO THE MIDDLE 50S IN THE
AFTERNOON, WHILE THE EAST WILL BE CONSIDERABLY COOLER IN THE GRIP
OF THE COLD HIGH PRESSURE, WITH HIGHS IN THE LOWER 40S. TUESDAY
MAY BE THE NEXT GOOD WITH HIGHS IN THE MID TO UPPER 50S. WINDS
TUESDAY WILL BE SHIFTING FROM THE SOUTHWEST IN THE MORNING AT
AROUND 10 MPH TO NORTHWEST IN THE AFTERNOON AT 10 TO 20 MPH.
ANOTHER COLD FRONT WILL SURGE SOUTHWARD THROUGH THE PLAINS AND
SHOULD CROSS SOUTHWESTERN KANSAS EARLY WEDNESDAY, AND BRING IN
ABUNDANT CLOUDS AND COLD AIR WITH IT. NO PRECIP ASSOCIATED WITH
THIS FRONTAL PASSAGE, BUT THERE MAY BE FEW FLURRIES ACROSS OUR
SOUTHERN HALF OF THE CWA BY WEDNESDAY NIGHT. THE SUPERMODEL ONLY
PLACE 15 PERCENT POPS, BASICALLY SOUTH OF HIGHWAY 50, AND I THINK
THAT IS ABOUT RIGHT. AN UPPER BROAD TROUGH WILL BE DEVELOPING OVER
THE MIDWEST, AND WE MAY SEE A LITTLE SYNOPTIC LIFT OVER THE COLD
AIR SETTLING IN.
THURSDAY AND FRIDAY WILL GO INTO WARMING TREND, WITH THURSDAY`S
HIGH`S AGAIN RANGING FROM THE MID 50S IN THE WEST TO THE LOWER
40S IN OUR EASTERN ZONES NEAR SAINT JOHN AND PRATT. IF THE PATTERN
DOES NOT CHANGE, NEXT FRIDAY COULD BE IN THE 60S IN MANY
LOCATIONS.
THIS IS THE LAST SHIFT OF MY 34 YEAR CAREER. IT HAS BEEN NICE.
SIGNING OFF....
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1120 AM CST FRI JAN 30 2015
NAM AND RAP WERE IN GOOD AGREEMENT TODAY WITH VFR CEILINGS
LOWERING THROUGH THE DAY AS ISENTROPIC LIFT AND MOISTURE ADVECTION
IMPROVE ACROSS WESTERN KANSAS. HRRR AND BUFR SOUNDINGS INDICATING
LOW VFR CEILINGS WILL DEVELOP AT GCK AND DDC AROUND 21Z FRIDAY AND
THEN CONTINUE TO LOWER WITH MVFR CONDITIONS DEVELOPING BETWEEN 00Z
AND 03Z SATURDAY AS SOME LIGHT RAIN DEVELOPS. AFTER 06Z CEILINGS
AND VISIBILITIES WILL FALL BACK INTO THE IFR CATEGORY AS THE
LOWER LEVELS SATURATES. AT HYS MVFR CEILINGS ARE EXPECTED TO
TOWARDS 06Z SATURDAY AND IFR CONDITIONS 12Z SATURDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 34 44 33 35 / 80 60 60 10
GCK 34 46 34 35 / 70 50 50 0
EHA 33 44 34 37 / 60 50 50 0
LBL 34 44 36 37 / 80 60 60 10
HYS 33 42 28 32 / 80 50 60 0
P28 36 42 38 38 / 80 70 70 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...BURKE
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1122 AM CST FRI JAN 30 2015
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1120 AM CST FRI JAN 30 2015
AT 12Z FRIDAY A 500MB RIDGE AXIS EXTENDED FROM WEST TEXAS INTO THE
CENTRAL HIGH PLAINS. JUST EAST OF THIS UPPER LEVEL RIDGE AXIS A
250MB JET STREAK STRETCHED FROM NEBRASKA INTO THE SOUTHEAST UNITED
STATES. THE RIGHT ENTRANCE OF THIS UPPER LEVEL JET WAS APPEARS TO
BE LOCATED OVER NORTHERN KANSAS. SOUTHERLY WINDS ACROSS WEST TEXAS
AT THE 700MB WAS DRAWING WARM AND MORE HUMID AIR NORTH INTO
SOUTHWEST KANSAS. DODGE CITY AND AMARILLO SOUNDINGS AT 12Z FRIDAY
INDICATED A DECENT DRY LAYER WAS LOCATED IN 850MB TO 700MB LAYER
BELOW THIS AREA OF INCREASING MOISTURE AND WARM AIR ADVECTION.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 242 AM CST FRI JAN 30 2015
MID TO UPPER LEVEL MOISTURE WILL INCREASE TODAY FROM WEST TO EAST
ALLOWING CLOUDY SKIES TO ENVELOP WESTERN KANSAS BY THIS AFTERNOON.
THERE LOOKS TO BE ENOUGH LIFT ACROSS THE AREA IN THE AFTERNOON FOR
PRECIPITATION TO START TO FALL IN THE MID LEVELS. HOWEVER, WITH
THE LOW LEVELS REMAINING DRY THIS PRECIPITATION WILL MOST LIKELY
EVAPORATE BEFORE IT REACHES THE GROUND LEADING TO VIRGA TO BE
OBSERVED. THE BETTER CHANCE OF PRECIPITATION OCCURS OVERNIGHT AS
THE LOWER PORTIONS OF THE ATMOSPHERE BECOMES SATURATED. THIS
PRECIPITATION SHOULD BE LIGHT IN NATURE, POSSIBLY ONLY FALLING AS
DRIZZLE AT TIMES. TEMPERATURES FALL NEAR FREEZING AFTER MIDNIGHT
AND THIS IS WHEN THE PRECIPITATION COULD MIX OR TURN OVER TO SNOW
BY SUNRISE TOMORROW. LITTLE TO NO ACCUMULATION IS EXPECTED AS
GROUND TEMPERATURES WILL REMAIN WARM AND MOST LIKELY MELT ON
CONTACT. OTHERWISE EXPECT MOSTLY CLOUDY SKIES TO CONTINUE
OVERNIGHT. HIGHS TODAY LOOK TO RANGE FROM THE MID 40S ACROSS FAR
SOUTHWESTERN KANSAS TO AROUND 50 DEGREES ACROSS THE I-70 CORRIDOR.
LOWS TONIGHT LOOK TO DIP TO AROUND FREEZING (32F).
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 324 AM CST FRI JAN 30 2015
THE COLD FRONT COMING THROUGH THIS WEEKEND HAS SLOWED A LITTLE, AND
WILL NOT CLEAR OUR SOUTHERN BORDER UNTIL SUNDAY EVENING.
THEREFORE, THERE WILL LIKELY BE A PROLONGED PERIOD OF A RAIN/SNOW
MIXTURE INTO EARLY AFTERNOON SATURDAY. THEN THE SOUTHERLY FLOW IN
THE SOUTH WILL ALLOW FOR A CHANGE TO ALL LIGHT RAIN SATURDAY
AFTERNOON. HOWEVER, THE COLD AIR WILL SETTLE IN SATURDAY NIGHT AND
THE PRECIPITATION WILL GO BACK TO A RAIN/SNOW MIX SATURDAY NIGHT.
THIS WILL CONTINUE INTO SUNDAY MORNING AS AN UPPER TROUGH DRAGS
ACROSS THE PLAINS. PRECIPITATION CHANCES WILL BE HIGHEST IN THE
EASTERN CWA SATURDAY, AND DIMINISH ON SUNDAY AS THE SYSTEM CLEARS
TO THE EAST. SATURDAY SHOULD BE A LITTLE WARMER THAN PREVIOUSLY
THOUGHT, DUE TO THE SLOWING OF THE FRONT`S SOUTHWARD PROGRESSION.
HIGHS SHOULD TOP OUT IN THE LOWER 40S NORTH OF I-70, AND THE
MIDDLE 40S DOWN SOUTH ALONG THE OKLAHOMA BORDER. SUNDAY WILL BE
CONSIDERABLY COLDER WITH CLOUDS, EARLY PRECIP AND WIND SHIFTING
SHARPLY TO THE NORTH AND INCREASING INTO THE 18G28MPH RANGE.
MONDAY SHOULD SEE THE UPPER FLOW TRANSITION FROM A NORTHWEST TO A
MORE WESTERLY ZONAL FLOW. SURFACE CONDITIONS WILL START TO WARM
AND THE WESTERN EDGE OF KANSAS WILL REACH TO THE MIDDLE 50S IN THE
AFTERNOON, WHILE THE EAST WILL BE CONSIDERABLY COOLER IN THE GRIP
OF THE COLD HIGH PRESSURE, WITH HIGHS IN THE LOWER 40S. TUESDAY
MAY BE THE NEXT GOOD WITH HIGHS IN THE MID TO UPPER 50S. WINDS
TUESDAY WILL BE SHIFTING FROM THE SOUTHWEST IN THE MORNING AT
AROUND 10 MPH TO NORTHWEST IN THE AFTERNOON AT 10 TO 20 MPH.
ANOTHER COLD FRONT WILL SURGE SOUTHWARD THROUGH THE PLAINS AND
SHOULD CROSS SOUTHWESTERN KANSAS EARLY WEDNESDAY, AND BRING IN
ABUNDANT CLOUDS AND COLD AIR WITH IT. NO PRECIP ASSOCIATED WITH
THIS FRONTAL PASSAGE, BUT THERE MAY BE FEW FLURRIES ACROSS OUR
SOUTHERN HALF OF THE CWA BY WEDNESDAY NIGHT. THE SUPERMODEL ONLY
PLACE 15 PERCENT POPS, BASICALLY SOUTH OF HIGHWAY 50, AND I THINK
THAT IS ABOUT RIGHT. AN UPPER BROAD TROUGH WILL BE DEVELOPING OVER
THE MIDWEST, AND WE MAY SEE A LITTLE SYNOPTIC LIFT OVER THE COLD
AIR SETTLING IN.
THURSDAY AND FRIDAY WILL GO INTO WARMING TREND, WITH THURSDAY`S
HIGH`S AGAIN RANGING FROM THE MID 50S IN THE WEST TO THE LOWER
40S IN OUR EASTERN ZONES NEAR SAINT JOHN AND PRATT. IF THE PATTERN
DOES NOT CHANGE, NEXT FRIDAY COULD BE IN THE 60S IN MANY
LOCATIONS.
THIS IS THE LAST SHIFT OF MY 34 YEAR CAREER. IT HAS BEEN NICE.
SIGNING OFF....
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1120 AM CST FRI JAN 30 2015
NAM AND RAP WERE IN GOOD AGREEMENT TODAY WITH VFR CEILINGS
LOWERING THROUGH THE DAY AS ISENTROPIC LIFT AND MOISTURE ADVECTION
IMPROVE ACROSS WESTERN KANSAS. HRRR AND BUFR SOUNDINGS INDICATING
LOW VFR CEILINGS WILL DEVELOP AT GCK AND DDC AROUND 21Z FRIDAY AND
THEN CONTINUE TO LOWER WITH MVFR CONDITIONS DEVELOPING BETWEEN 00Z
AND 03Z SATURDAY AS SOME LIGHT RAIN DEVELOPS. AFTER 06Z CEILINGS
AND VISIBILITIES WILL FALL BACK INTO THE IFR CATEGORY AS THE
LOWER LEVELS SATURATES. AT HYS MVFR CEILINGS ARE EXPECTED TO
TOWARDS 06Z SATURDAY AND IFR CONDITIONS 12Z SATURDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 45 33 44 33 / 20 80 60 60
GCK 46 33 43 34 / 30 70 50 50
EHA 46 32 45 34 / 40 60 50 50
LBL 46 33 46 36 / 30 80 60 60
HYS 47 32 42 28 / 20 80 60 60
P28 47 34 44 38 / 10 70 70 70
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...HOVORKA_42
LONG TERM...BURKE
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS TOPEKA KS
356 AM CST Fri Jan 30 2015
.SHORT TERM...(Today and Tonight)
Issued at 350 AM CST FRI JAN 30 2015
Recent IR satellite and water vapor imagery showing high level
moisture/clouds spreading eastward across KS from the upper
trough in the southwest CONUS. Although initially thin...the clouds
will steadily but slowly thicken west to east across the cwa today
into this evening before becoming totally overcast tonight.
However...should still see some insolation combining with veering
low level flow to the south by afternoon and warm advection through
850 mb to push highs into the middle to upper 40s.
Clouds...some mixing and continued warm air advection tonight would
suggest nearly steady or even slightly rising temperatures in some
areas...however expect some evaporative cooling to occur so only
tweaked lows up slightly into the lower 30s. Forecast soundings
still showing freeze levels a little high for much snow to make it
to the ground before melting...but will keep it across the west and
north and go only rain chances south (east central) for now. Either
way...higher pops and no snow accumulation still in order across the
cwa overnight with rainfall amounts generally under a tenth of an
inch...especially east.
.LONG TERM...(Saturday through Thursday)
Issued at 350 AM CST FRI JAN 30 2015
Saturday through Saturday Night, An upper level trough across the
southwestern US will slowly move east into far west TX, while an
upper level trough embedded within the northern stream of the mid
and upper level jet digs southeast across the northern and central
high plains. Slightly warmer boundary layer air parcels will
advect northward across the CWA through he morning hours of
Saturday. Surface temperatures will warm from the lower to mid 30s
at 12Z Saturday into the mid and upper 30s by noon. Forecast
soundings show the depth of the warmer boundary layer airmass to
be warm enough to change the mix of rain and snow across much of
the CWA over to periods of light rain through the mid and late
morning hours of Saturday. Most of the CWA will see light rain
through the afternoon hours into the mid and late evening hours.
After midnight, the northern stream H5 trough will dig southeast
across the central plains bringing cooler air at both the surface
and 850mb. The light rain will begin to mix with snow and will
change over to light snow during the early morning hours of
Sunday. Most of the stronger ascent and frontogenetical forcing
will shift northeast of the CWA, thus any snow accumulations will
be light, with a dusting or less. The best chance of seeing
measurable snowfall will be across the northern counties of the
CWA where an inch of snow may fall late Saturday evening into
Sunday Morning. Some areas along the NE border may get over an
inch of snowfall, perhaps near 2 inches in northern Brown County.
Most areas should see about a half inch of rainfall with the eastern
counties receiving between one half and three quarters of an inch of
QPF. Once again the cold air in the low-levels will arrive too late
to see much in the way of snowfall. Overnight lows will drop into
the 20s across north central and northeast KS with lower to mid 30s
across east central KS.
Sunday through Sunday Night, the central plains H5 trough will
amplify On Sunday as it digs east-southeast across the mid MS
river valley. Portions of northern IL, northern IN and Northern OH
will see 6 to 8 inches of snowfall on Sunday. There may be some
left over flurries for very light snow during the morning hours of
Sunday across the eastern counties of the CWA. Strong low-level
CAA will only allow Highs to reach the mid 20s along the NE border
to the mid 30s across the southeast counties. North winds of 15 to
25 MPH with higher gusts will make it feel much colder on Sunday.
Any leftover moisture on area roadways may freeze causing slick
spots on area roadways Sunday morning.
Lows Sunday night will drop into the teens and perhaps some single
digits along the NE border.
Monday through Thursday, A longer wave length upper trough will
remain across the eastern US. Monday will continue to be cold as a
surface ridge of high pressure builds southeast across eastern KS.
Highs will only reach the lower to mid 30s. We`ll see a brief warm
up on Tuesday ahead of the next surge of cold air by mid week. Highs
on Tuesday will reach the mid to upper 40s. Wednesday another
strong cold front will move southward across the CWA. Highs on
Wednesday may occur during the morning hours, with temperatures
falling into the 20s by afternoon. Highs on Thursday will only
reach the mid 20s to lower 30s, though the ECMWF if much colder and
if it were to verify, highs may only reach the teens. An H5 trough
embedded in the northwesterly flow aloft will track southeast across
CO into OK and bring a chance of accumulating snowfall to western
and southern KS on Thursday.
&&
.AVIATION...(For the 06Z TAFs through 06Z Friday Night)
Issued at 1129 PM CST THU JAN 29 2015
Will continue with VFR conditions, though a few brief issues
possible. Some BR potential remains in the hours near 12Z, though
some wind persists on area obs and thickening high cloud arrives
near this time. HRRR visibility output has been too aggressive with
lowering values so far as well. Precip concern ramps up mainly
near MHK at the end of this forecast, but not convinced on
occurrence and intensity for inclusion.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...63
LONG TERM...Gargan
AVIATION...65
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1129 PM CST Thu Jan 29 2015
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Friday)
Issued at 253 PM CST THU JAN 29 2015
The shortwave that moved over the region will continue eastward into
the mid MS valley. In the wake of the departing system high pressure
will build in from the northwest overnight. Meanwhile the cloud
cover in place should gradually erode and trend eastward, which is
evident on the latest satellite loop. Winds will decrease this
evening as the pressure gradient weakens near the high center. Skies
will clear out after sunset allowing decent rational cooling to take
effect as the surface ridge slides across the area. Timing of the
ridge should place it directly bisecting the forecast area during
early morning hours, which should strengthen the nocturnal
inversion. Therefore, have went lower than guidance regarding
temperatures tonight, which drop into the upper 10s and lower 20s.
Due to the limited moisture in the boundary layer and soil do not
expect fog to develop although reduced visibilities or haze will be
possible. The stronger northwest flow aloft gets shunted off to the
east as the ridge builds in ahead of the system over the southwest
US. High pressure retreats allowing for return flow and increase in
mid to high level clouds. Advection is rather weak tomorrow so
expect high temperatures in the 40s like today although with much
less wind.
.LONG TERM...(Friday Night through Thursday)
Issued at 253 PM CST THU JAN 29 2015
By Friday evening, system moving out of the southwest starts to
bring rain into the area from the west. Temperatures remain near
steady in the 30s and are generally near or above freezing for
much of Friday night into Saturday. That being said, considering
that temperatures are below freezing above the surface, expect
that a mix of rain and snow will fall through the overnight hours.
Not expecting much to accumulate, but could bring some slick spots
on roads overnight.
By Saturday around noon, enough warm air is forecast to push back
northward to change precipitation back over to rain, save the
colder counties along the Nebraska border which are more likely
to see a rain/snow mix. Secondary upper wave dropping in from the
northwest starts to push colder temperatures back into eastern
Kansas, and the rain/snow mix shifts slowly southeast through the
evening. Some light accumulations are possible along the Nebraska
border in the afternoon. At this time, around 03z the freezing
mark is forecast to have shifted across the area and will change
precipitation back over to all snow. This could be bit aggressive
with the colder air, and the southeast counties may see a later
start to any falling snow. 06-12z have forecast 1-2 inches across
the northeast and eastern counties. As the colder air drives
southward through the day on Sunday, may see an additional inch or
so across the far east northeast as another weak wave moves across
those areas. Total amounts forecast are highest over Brown/Nemaha
counties with nearly 4 inches, but tapers to 1-2 inches along the I70
corridor. Overall, temperatures are so close to freezing and make
this a challenging forecast, as does the initial warm air
advection followed by the then stronger cold front and secondary
wave, so anticipate some adjustments to amounts as event draws
closer.
Sunday night as cold high pressure moves overhead, lows fall into
the teens. Highs on Monday should rise back into the 30s as
southerly winds and the high plains lee trof return. May make it
back up into the 40s Tuesday before the next cold front comes
through Tuesday night with another reinforcing shot late
Wednesday. Highs overall in the 30s with lows in the upper teens
to 20s.
&&
.AVIATION...(For the 06Z TAFs through 06Z Friday Night)
Issued at 1129 PM CST THU JAN 29 2015
Will continue with VFR conditions, though a few brief issues
possible. Some BR potential remains in the hours near 12Z, though
some wind persists on area obs and thickening high cloud arrives
near this time. HRRR visibility output has been too aggressive with
lowering values so far as well. Precip concern ramps up mainly
near MHK at the end of this forecast, but not convinced on
occurrence and intensity for inclusion.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sanders
LONG TERM...67
AVIATION...65
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
615 PM EST SAT JAN 31 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM EST SAT JAN 31 2015
THIS AFTERNOON THROUGH SUNDAY...HIGH PRESSURE SLIDING ACROSS CENTRAL
CANADA THIS AFTERNOON HAS ALLOW NORTHERLY FLOW TO INCREASE ACROSS
MUCH OF THE UPPER GREAT LAKES REGION. THIS NORTHERLY FLOW COUPLED
WITH 850MB TEMPERATURES COOLING TO AROUND -18C TO -20C HAS ALLOWED
LAKE EFFECT SNOW TO DEVELOP AHEAD OF THE SURFACE HIGH PRESSURE
SYSTEM. INITIALLY...DEEPER MOISTURE WILL LINGER INTO THE EARLY
EVENING HOURS ALLOWING BETTER SNOW GROWTH WITH A THICKER SNOW GROTH
AREA WITHIN THE DGZ. RUC SOUNDINGS SHOW INVERSION HEIGHTS BETWEEN
4KFT AND 5KFT THIS AFETERNOON WHICH IS ALSO VERIFIED BY THE MQT VAD
WIND PROFILE THIS AFETERNOON. THIS HAS ALLOWED GOOD SNOWFLAKE SIZE
THIS AFTERNOON RESULTING IN A QUICK INCH OR TWO OF FLUFFY SNOW ON A
NORTH TO NORTHWESTERLY WIND. DRY AIR REMAINS JUST TO THE NORTH OF
THE AREA THIS AFTERNOON...HOWEVER...THIS IS EXPECTED TO SHIFT
FARTHER SOUTH AROUND 00Z/01 AS INVERSION HEIGHTS BEGIN TO FALL TO
AROUND 3KFT. THIS SHOULD HELP TO REDUCE SNOWFALL RATES THIS EVENING
INTO THE OVERNIGHT HOURS.
AS THE SURFACE RIDGE EXPANDS TO THE NORTH OF LAKE SUPERIOR EXPECT
WINDS TO SHIFT TO THE NORTH AND NORTHEAST SHIFTING THE SNOWBANDS TO
THE NORTH TO NORTHEAST WIND FAVORED SNOW BELTS. AGAIN...REDUCED
MOISTURE...LOWERED INVERSION HEIGHTS ALONG WITH ANTICYCLONIC FLOW
WILL HELP TO KEEP SNOWFALL TOTALS IN CHECK ACROSS THE U.P. WITH UP
TO 2 INCHES EXPECTED ALONG THE NORTH TO NORTHEAST WIND FAVORED SNOW
BELTS. AS THE SURFACE RIDGE CENTER SHIFTS INTO THE NORTHERN PLAINS
ON SUNDAY EXPECT WINDS TO SHIFT TO A MORE NORTHERLY DIRECTION.
TEMPERATURES ALOFT WILL REMAIN COLD ENOUGH AND LOW LEVEL MOISTURE
OFF LAKE SUPERIOR WILL KEEP LAKE EFFECT SNOW IN NORTHERLY WIND
FAVORED LOCATIONS...WITH AROUND AN INCH ACCUMULATION EXPECTED IN
THESE AREAS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM EST SAT JAN 31 2015
...NW FLOW LES AND POOR VSBY DUE TO BLSN/DRSN MAY LEAD TO HEADLINES
WEDNESDAY INTO THURSDAY...
COLD WEEK IN STORE AS A BUILDING RIDGE ALOFT OVER WESTERN NORTH
AMERICA RESULTS IN MEAN TROUGHING CENTERED OVER HUDSON BAY EXTENDING
OVER GREAT LAKES AND NORTHEAST CONUS. PATTERN DOES NOT HOLD MUCH
OPPORTUNITY FOR WIDESPREAD SNOW. BEST CHANCE OF THAT MAY ACTUALLY
COME FRIDAY. OTHERWISE...LAKE EFFECT SNOW AND BLOWING/DRIFTING SNOW
WITH POOR VISIBILITY WILL BE MAIN ISSUE. APPEARED THAT MODERATION IN
THE CHILL WOULD START TO DEVELOP BY NEXT WEEKEND...BUT RECENT RUNS OF
THE ECMWF/GFS HAVE TRENDED TOWARD MORE TROUGHING AND COLDER
TEMPERATURES. WILL HAVE TO WAIT AND SEE IF THIS IS A LASTING TREND.
HIGH IMPACT WEATHER THAT JUSTIFIES ANY TYPE OF HEADLINES THROUGH THE
EXTENDED LIKELY WILL BE TIED TO THE LAKE EFFECT SNOW AND POOR VSBY.
BEST CHANCE OF SEEING HEADLINES WILL BE WEDNESDAY INTO THURSDAY FOR
NW FLOW AREAS NEAR LK SUPERIOR. WILL ALSO GIVE AN HONORABLE MENTION
FOR WSW FLOW ON TIP OF KEWEENAW PENINSULA LATE MONDAY INTO MONDAY
NIGHT...AS THOUGH THIS IS A VERY LOW PROBABILITY EVENT IT COULD NEED
A HEADLINE IF IT OCCURS. SUPPOSE THERE ALSO COULD BE NEED FOR WIND
CHILL ADVYS MONDAY MORNING AND AGAIN THURSDAY MORNING...BUT ATTM IT
DOES NOT LOOK LIKE A SURE THING THANKS TO LIGHT WINDS AND/OR MORE IN
TERMS OF LAKE MODERATION ON TEMPS.
NO REAL HAZARDOUS WEATHER EXPECTED SUNDAY NIGHT INTO MONDAY MORNING
WITH DIMINISHING WINDS AND WEAK LES AS INVERSIONS ARE WELL BLO 5KFT.
PLENTY COLD WITH TEMPS AT INVERION TOP BLO -20C. SLR/S ON THE
HIGHER/FLUFFY SIDE SO A COUPLE OF INCHES OF SNOW IS POSSIBLE FOR
MAINLY NCNTRL UPR MICHIGAN. GIVEN THE WEAKENING WINDS...MESOLOW
FORMATION REMAINS POSSIBLE WHICH WOULD ENHANCE CONVERGENCE AND ADD
TO THE SNOW AMOUNTS. HIGHEST PROBABILITY OF THIS OCCURRING WOULD BE
BTWN MARQUETTE AND PICTURED ROCKS LAKESHORE...SO LOOKING AT AU TRAIN
AND MUNISING AREAS. AWAY FM THE LES...TEMPS FALL WELL BLO ZERO LATE
SUNDAY NIGHT INTO MONDAY MORNING...BUT WITH LIGHT WINDS AND SOME
LAKE MODERATION/LAKE EFFECT CLOUDS...WIND CHILLS WILL MAINLY STAY
HIGHER THAN 20 BLO. SFC TROUGH CROSSING THE AREA MONDAY MORNING
SHOULD RESULT IN WINDS BECOMING MORE WESTERLY WHICH WILL DISRUPT THE
LES OVER ALGER COUNTY BUT WILL INCREASE IT ON THE KEWEENAW PENINSULA.
WESTERLY CONVERGENT FLOW LES HAS POTENTIAL TO DROP SEVERAL INCHES OF
SNOW LATE MONDAY AFTN INTO MONDAY NIGHT OVER NORTHERN SECTIONS OF
THE KEWEENAW. SOUNDINGS SHOW INVERSION AT LEAST TO 5KFT AND
DISTURBANCE ROTATING THROUGH AHEAD OF ANOTHER TROUGH MOVING OVER
UPPER GREAT LAKES ON TUESDAY MORNING. NAM SHARPER WITH TROUGH AND
BACKS WINDS ENOUGH TO KEEP HEAVIER LES OFFSHORE OF KEWEENAW. GFS AND
ECMWF NOT AS BACKED WITH WINDS. WILL CONTINUE TO SHOW HIGHEST POPS
ON THE KEWEENAW AND MENTION IN HAZARDOUS WEATHER OUTLOOK.
TROUGH SINKS OVER NORTHERN UPR MICHIGAN THROUGH DAY ON TUESDAY...
SPREADING THE LES TO NW FLOW SNOW BELTS OF NORTHERN UPR MICHGAN...
ESPECIALLY BY TUESDAY NIGHT. SOUNDINGS SHOW INVERSIONS UP TO 6-8 KFT
IN WAKE OF THE TROUGH WITH AS H85 TEMPS DROP TO -25C BY DAYBREAK ON
WEDNESDAY. SETUP WILL THEN FAVOR A PUSH OF HEAVIER LES AS THE MAIN
COLD FRONT MOVES THROUGH TUESDAY NIGHT INTO WEDNESDAY MORNING WITH
CONDITIONS QUICKLY TRANSITIONING TO SMALL SNOWFLAKE/LOW VSBY LES
REGIME FOR THE NORTHWEST WIND SNOW BELTS WEDNESDAY AFTN INTO
WEDNESDAY NIGHT. BLYR WINDS INCREASE THROUGH WEDNESDAY TO 25-30 KTS
SO BLSN AND DRSN WILL ALSO BECOME A CONCERN IN OPEN AREAS NEAR LK
SUPERIOR AND ESPECIALLY WHERE ICE IS BUILT UP ALONG THE SHORELINE.
AWAY FM THE LES THE MAIN THEME WILL BE COLD. TEMPS ON WEDNESDAY WILL
ONLY STRUGGLE INTO THE SINGLE DIGITS ABOVE ZERO WITH WIND CHILL
READINGS 10 TO 20 BLO ZERO. AS TEMPS FALL OFF WELL BLO ZERO ON
WEDNESDAY NIGHT OVER WESTERN UPR MICHIGAN...MAY SEE WIND CHILL
READINGS MAY COME CLOSE TO ADVY INTO THURSDAY MORNING. WINDS WILL BE
SLACKENING BY THIS TIME THOUGH...ESPECIALLY OVER INTERIOR SECTIONS
OF CWA. A BIT OF MODERATION ON THURSDAY FOR HIGHS WITH READINGS
NEARING 10 DEGREES OR REACHING THE LOWER TEENS. BLYR WINDS BACK SW
LATER THURSDAY INTO THURSDAY NIGHT AS HIGH PRESSURE RIDGE SETTLES FM
THE MIDDLE MISSISSIPPI RIVER VALLEY TO THE OHIO VALLEY. EXPECT THE
LES TO SHIFT OFFSHORE BY THURSDAY NIGHT. SINCE UPPER LAKES WILL BE
AHEAD OF ANOTHER SFC TROUGH CROSSING SOUTH CENTRAL CANADA...EXPECT
CLOUDS TO BE ON THE INCREASE WITH EVEN A POSSIBILITY OF LGT SNOW OR
FLURRIES. THUS...TEMPS SHOULD NOT CRASH TOO MUCH ON THURSDAY NIGHT.
STRONGER COLD FRONT WITH ANOTHER PUSH OF COLDER AIR EXPECTED TO
ARRIVE FRIDAY NIGHT INTO SATURDAY. SHORTWAVE/CONVERGENCE ALONG THE
SFC-H85 FRONT AND UPPER DIVERGENCE ON NOSE OF H3 JET STREAK COMBINE
TO SPREAD SWATH OF SNOW OVER MOST OF UPR MICHIGAN FRIDAY AFTN INTO
FRIDAY EVENING. TIMING MAY SHIFT AROUND SOME THOUGH CONSIDERING THIS
SOLUTION IN THE MODELS IS NEWER DEVELOPMENT. LOW CHANCE POPS WILL
WORK FOR NOW WITH THE SNOW ALONG THE COLD FRONT AND THEN MORE LOW
CHANCE POPS FOR NEXT SATURDAY WITH DEVELOPING NE FLOW LES IN WAKE OF
THE FRONT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 614 PM EST SAT JAN 31 2015
MVFR CONDITIONS WILL CONTINUE FOR ALL SITES THIS FORECAST PERIOD.
THERE COULD BE BRIEF IFR CONDITIONS AT SAW THIS EVENING DUE TO
NORTHEAST UPSLOPE FLOW IN HEAVIER SNOWBANDS THAT WOULD BRING DOWN
VISIBILITIES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 340 PM EST SAT JAN 31 2015
A COLD FRONT THAT SHIFTED SOUTH AND EAST OF THE AREA THIS AFTERNOON
ALONG WITH A DECENT PRESSURE GRADIENT ON THE BACK SIDE WILL ALLOW A
FEW GUSTS TO REACH 35KTS THIS AFTERNOON AND EVENING. MUCH LIGHTER
WINDS WILL PREVAIL SUNDAY AS HIGH PRESSURE DRIFTS ACROSS THE UPPER
GREAT LAKES REGION. LOW PRESSURE AND ASSOCIATED COLD FRONT WILL
APPROACH THE AREA MONDAY NIGHT AND THEN SWEEP THROUGH THE AREA
TUESDA NIGHT AND WEDNESDAY. ON THE BACK SIDE OF THIS SYSTEM...WINDS
WILL INCREASE FROM THE NORTHWEST WEDNESDAY AFTERNOON THROUGH
THURSDAY...WITH GALE FORCE GUSTS TO 35 KNOTS POSSIBLE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 5 AM EST SUNDAY FOR LSZ264-
266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KEC
LONG TERM...JLA
AVIATION...07
MARINE...KEC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
432 PM EST FRI JAN 30 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 406 PM EST FRI JAN 30 2015
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
HUDSON BAY INTO THE NE CONUS RESULTING IN NW FLOW THROUGH THE NRN
GREAT LAKES. AN UPSTREAM SHORTWAVE TROUGH WAS LOCATED OVER SRN
MANITOBA. THE SHRTWV AND ASSOCIATED WAA PATTERN SUPPORTED SOME LIGHT
SNOW FROM FAR NRN MN INTO NW ONTARIO WITH VSBY INTO THE 1-3SM RANGE.
AT THE SFC...A RIDGE EXTENDED FROM THE MID MS VALLEY INTO THE WRN
GREAT LAKES. BACKING WINDS TO SW OVER WRN LAKE SUPERIOR AND W OVER
THE ERN LAKE HAVE PUSHED THE LES BANDS OFFSHORE EXCEPT FOR SOME
LINGERING FLURRIES NEAR GRAND MARAIS.
TONIGHT...EXPECT MID/HIGH CLOUDS TO THICKEN INTO THIS EVENING AS THE
AS THE SHRTWV APPROACHES. UPSTREAM TRENDS AND MODELS FCST 285K-290K
ISENTROPIC LIFT...SUGGESTS THAT THE AREA OF LIGHT SNOW WILL SPREAD
THROUGH UPPER MICHIGAN BTWN 03Z-09Z. WITH LITTLE MOISTURE AVAILABLE
AND DRY LOW LEVELS DELAYING THE ONSET OF THE PCPN...QPF OF 0.05 OR
LOWER WITH SLR VALUES NEAR 20/1 WOULD ONLY RESULT IN SNOW AMOUNTS OF
AN INCH OR LESS. HOWEVER...AS LOW LEVEL CONV INCREASES ALONG THE SFC
FRONT/TROUGH AND 850 MB TEMPS DROP TO AROUND -12C...THERE MAY BE A
BRIEF PERIOD OF LAKE ENHANCED SNOW INTO NW UPPER MI THAT MAY BRING
TOTALS INTO THE 1 TO 2 INCH RANGE.
SAT...THE AREA OF LOW LEVEL CONV WITH THE FRONT WILL SLIDE THROUGH
THE REST OF THE NRN CWA WITH THE POTENTIAL FOR A NARROW BAND OF
MODERATE SNOW. ALTHOUGH 850 MB TEMPS DROP TO NEAR -20C BY 00Z
SUN...A QUICK TRANSITION TO A MORE DIFFLUENT/ANTICYCLONIC LOW-LVL
NORTHERLY FLOW AND FALLING INVERSIONS AT OR BELOW 4KFT WILL LIMIT
LES INTENSITY THE REST OF THE DAY. SNOW ACCUMULATIONS OF ONLY AROUND
AN INCH ARE EXPECTED. AFTER MIDDAY HIGHS RANGING FROM THE TEENS NW
TO MID TO UPPER 20S SCNTRL...TEMPS WILL DURING THE AFTERNOON AS
BRISK N TO NW WINDS USHER ARCTIC AIR MASS INTO THE AREA. GUSTY WINDS
WILL ALSO CREATE BLSN IN OPEN AREAS NEAR LAKE SUPERIOR.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 424 PM EST FRI JAN 30 2015
COLD WEATHER PATTERN IN STORE FOR MUCH OF EXTENDED. TEMPS WILL BE
MUCH BLO NORMAL...ESPECIALLY FOR DAYTIME HIGHS. NORMAL HIGHS FOR
FIRST PORTION OF FEBRUARY ARE IN THE LOWER TO MIDDLE 20S...AND THERE
WILL BE A FEW DAYS NEXT WEEK WHERE HIGHS STAY BLO 10 ABOVE. TROUGHING
ALOFT EXPANDS FM NORTHERN CANADA OVER GREAT LAKES AND MOST OF THE
EASTERN CONUS AS RIDGING TEMPORARILY BUILDS OVER THE WEST COAST. LEAD
SHOT OF ARCTIC AIR DROPS OVER GREAT LAKES SECOND HALF OF THE WEEKEND
WITH H85/5KFT AGL TEMPS BLO -20C/-3F. ANOTHER STRONGER PUSH OF COLDER
AIR IS DUE IN THE MIDDLE OF THE WEEK AS H85 TEMPS DROP TO AT LEAST
-25C/-13F. COULD BE A WIDESPREAD SNOW JUST AHEAD OF THAT REINFORCING
COLD FRONT TUESDAY NIGHT INTO WEDNESDAY. SINCE THE RIDGING OVER THE
WEST COAST IS NOT THAT SHARP...WESTERN RIDGE AND EASTERN TROUGH
PATTERN BREAKS DOWN BY NEXT WEEKEND WITH TEMPS MODERATING BACK TOWARD
NORMAL...POSSIBLY ABOVE...BY NEXT WEEKEND.
COLD FRONT MOVES EAST OF THE AREA ON SATURDAY NIGHT. ARCTIC HIGH
PRESSURE BUILDS FM THE CANADIAN PRAIRIES TO THE NORTHERN PLAINS.
RIDGING EXTENDS NORTH OF LK SUPERIOR WITH CONFLUENT FLOW ALOFT.
SOUNDINGS INDICATE INVERSIONS 4 TO POSSIBLY 6 KFT WITH DELTA T/S
INCREASING FM AROUND 18C SATURDAY EVENING TO 25C BY SUNDAY MORNING.
MAJORITY OF DGZ NOT WITHIN LAKE CONVECTIVE LAYER...SO SNOWFLAKE SIZE
AND THUS SLR/AMOUNTS WILL BE HELD DOWN TO AROUND 20:1 OR EVEN LOWER.
LOW-LEVEL WINDS START OUT NNW-N ON SATURDAY EVENING AND TURN TO NNE
BY SUNDAY AS RIDGING EXPANDS NORTH OF LK SUPERIOR. SETUP FAVORS LES
WITH MAINLY LIGHT ACCUMS FOR FAR WEST CWA AND OVER THE NCNTRL CWA.
SOUNDINGS INDICATE POSSIBLE WEAK LAKE ENHANCED SETUP AS SWATH OF H7-
H5 MOISTURE MOVES ACROSS SATURDAY EVENING INTO SUNDAY MORNING.
EXTENT OF DRYING BTWN THE MID-LEVEL MOISTURE AND LAKE CONVECTIVE
LAYER MAY BE TOO MUCH TO OVERCOME THOUGH AS LIFT ALOFT IS WEAK. LOW-
LEVEL CONVERGENCE VCNTY OF NORTH CENTRAL UPR MICHIGAN MAY MAKE UP
FOR OVERALL MARGINAL SETUP FOR LES...BUT EVEN SO...DO NOT EXPECT
MORE THAN A FEW INCHES OF SNOW SATURDAY NIGHT INTO SUNDAY FOR
FAVORED AREAS. WINDS ARE NOT VERY STRONG...SO SNOW SHOWERS MAY TRY
TO STAY CONFINED TOWARD THE SHORE INSTEAD OF SETTING UP OVER THE
HIGHER TERRAIN.
DESPITE THE ARRIVAL OF THE ARCTIC AIR...WINDS SHOULD NOT BE TOO
STRONG...LIMITING THE OVERALL IMPACT. TEMPS SATURDAY NIGHT SHOULD
FALL WELL BLO ZERO OVER THE EAST WITH DRAINAGE FLOW OFF ONTARIO.
OTHERWISE...NE FLOW AND WEALTH OF STRATUS OFF LK SUPERIOR BENEATH A
SUBSIDENCE INVERSION WILL RESTRICT TEMPS FM FALLING BLO ZERO.
STRATUS SHOULD STAY IN PLACE FOR MUCH OF SUNDAY...EXCEPT OVER THE
FAR EAST. HIGHS ON SUNDAY WILL STAY IN THE SINGLE DIGITS AND MAY
JUST STRUGGLE ABOVE ZERO IN THE FAR EAST CWA. ARRIVAL OF ANOTHER
SHORTWAVE FM THE NORTHWEST ACROSS THE PLAINS WILL BRING A SWATH OF
SNOW TO AS CLOSE AS NORTHERN WI LATE SATURDAY NIGHT. THAT SYSTEM
PHASES WITH ANOTHER MOVING OUT OF THE REMNANT OF CURRENT SOUTHWEST
CONUS LOW TO PROVIDE WIDESPREAD SNOW ON SUNDAY ALONG DEVELOPING SFC
LOW OVER MAINLY SOUTHERN PORTIONS OF WISCONSIN AND MICHIGAN. LOOKS
LIKE UPR MICHIGAN WILL MISS THIS STORM SYSTEM. EXPECT LINGERING
WEAKENING LES FOR SNOW BELTS TO EAST OF MARQUETTE AND POSSIBLY OVER
THE NORTHWEST CWA. LES WILL CONTINUE TO DRIFT MAINLY OFFSHORE ON
SUNDAY NIGHT AS WINDS IN BLYR SLOWLY BACK TO THE WEST ON EDGE OF
HIGH PRESSURE SINKING OVER THE MIDDLE MISSISSIPPI RIVER VALLEY.
CHILLY TEMPS FOR SUNDAY NIGHT WELL BLO ZERO...ESPECIALLY IN THE WEST
INTERIOR AND ALSO EAST CWA WITH CONTINUATION OF LOW-LEVEL FLOW OFF
ONTARIO. SINCE WINDS ARE LIGHT AND CALM...NO WIND CHILL ISSUES ARE
EXPECTED.
LES DRIFTS FARTHER EAST TO SNOW BELTS EAST OF MUNISING AND LIKELY
INCREASES ON THE KEWEENAW AS WINDS BECOME MORE CONVERGENT FM THE
WEST. SETUP THEN MAY BECOME FAVORABLE FOR MODERATE TO POSSIBLY HEAVY
LAKE ENHANCED SNOW FOR NORTHERN KEWEENAW LATE MONDAY INTO TUESDAY
MORNING AS WSW FLOW RESULTS IN STRONG CONVERGENCE BAND TO FORM WHILE
SHORTWAVE WITH ADDITIONAL MID-LEVEL LIFT AND MOISTURE SLIDES ACROSS.
SOUNDINGS INDCIATE THAT INVERSIONS REACH MORE TOWARD 8KFT WITH
INVERSION TOP TEMPS NEARING -24C. POTENTIAL FOR HEAVY SNOW WITH
RATES OVER 1 INCH PER HOUR WILL GREATLY DEPEND ON WHERE SHARPEST
CONVERGENCE ALLIGNS. TOUGH TO TELL THAT AT THIS POINT WHERE THAT
OCCURS...BUT WORTH AN HWO MENTION AS THIS TYPE OF LES PATTERN CAN
RESULT IN A LOT OF SNOW IN JUST A FEW HOURS.
ON INTO TUESDAY...LOW PRESSURE SYSTEM WILL BE ADVANCING ACROSS THE
NORTHERN PLAINS. AREA OF H7-H5 Q-VECTOR CONVERGENCE TO THE NORTH AND
EAST OF THE LOW AND AREA OF DIVERGENCE IN RIGHT ENTRANCE REGION OF
JET STREAK SLIDING OVER THE UPPER GREAT LAKES SHOULD SPREAD AN AREA
OF LGT SNOW WEST TO EAST ACROSS THE WESTERN GREAT LAKES. WENT WITH
LOW POPS AWAY FM LAKE EFFECT AREAS...ESPECIALLY AS THE ECMWF KEEPS
MOST WIDESRPEAD QPF SOUTH OF UPR MICHIGAN. LOW PRESSURE SYSTEM
SHOULD BE JUST EAST OF UPR MICHIGAN WEDNESDAY MORNING WITH STRONGER
COLD FRONT POISED TO SWEEP ACROSS. EXPECT NW FLOW LAKE EFFECT TO
RAMP UP WEDENSDAY AFTN AS NEW SURGE OF COLD AIR RETURN TO THE AREA.
ECMWF/GFS VARYING ON HOW COLD IT GETS AT H85. BLEND OF 12Z RUNS
SUGGEST H85 TEMPS END UP AROUND -27C/-17F WHICH WITH LAKE TEMPS IN
ICE FREE AREAS AROUND 2C/35F YIELDS PLENTY OF OVER-WATER
INSTABILITY. ALSO...COMPARED TO THE RECENT LAKE EFFECT EVENTS...THE
FORECAST SOUNDINGS INDICATE INVERSIONS MAY CLIMB TOWARD 8KFT. DUE TO
THE COLD AIR...SLR/S WILL BE LOWER...BUT WHATEVER LES OCCURS WILL BE
EFFICIENT AT REDUCING VSBY. SEEMS THAT SOME HAZARDS FOR THE SNOW AND
BLSN MAY BE NEEDED AND LOW VSBY AFFECT WOULD ONLY BE ENHANCED DUE TO
THE ICE COVER NEAR THE SHORELINE OF LK SUPERIOR. WILL MENTION THIS
IN THE HWO.
WILL BE AROUND WIND CHILL ADVISORY CRITERIA FOR AT LEAST WESTERN CWA
LATE WEDNESDAY NIGHT INTO THURSDAY MORNING AS TEMPS DROP TOWARD 10
BELOW AND WINDS ARE AT LEAST 5-10 MPH FM THE NW. ELSEWHERE...NW FLOW
OFF LK SUPERIOR WILL MODERATE TEMPS AND KEEP WIND CHILLS ABOVE 20
BELOW. LES DIMINISHES AND EVENTUALLY ENDS BY NEXT FRIDAY AS WINDS
BACK SW WITH HIGH PRESSURE DROPPING ACROSS THE CENTRAL PLAINS. COLD
FOR ALL ON FRIDAY MORNING WITH MOST AREAS BLO ZERO...BUT WINDS SHOULD
BE LIGHT ENOUGH TO RESTRICT WIND CHILL ISSUES AT THAT TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1249 PM EST FRI JAN 30 2015
WITH OFFSHORE WINDS...VFR CONDITIONS ARE EXPECTED AT IWD/SAW INTO
THIS EVENING. HOWEVER....LAKE EFFECT CLOUDS AND SNOW SHOWERS WILL
LINGER AT CMX THIS LATE AFTERNOON UNTIL WINDS BACK TO THE SW AND
INCREASE. A PERIOD OF IFR/MVFR VSBY WILL GIVE WAY TO VFR VSBY EVEN
AS THE MVFR CIGS PERSIST. A TROUGH OF LOW PRESSURE NEARING FROM THE W
THAT WILL BRING HIGH CLOUDS ACROSS THE REGION THIS AFTERNOON. THE
TROUGH OVER NW MN AT 00Z/SAT WILL AND CROSS CENTRAL LAKE SUPERIOR BY
12Z. LOOK FOR -SN TO MOVE IN DURING THE EVENING HOURS...AND PICK UP
IN INTENSITY ALONG AND BEHIND THE FRONT. LES AND GUSTY WINDS
PRODUCING BLSN AND LOWER VSBY IS EXPECTED AT CMX BY MID MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 PM EST FRI JAN 30 2015
BRIEF LULL IN STRONGER WINDS OVER LK SUPERIOR ATTM AS HIGH PRESSURE
DRIFTS ACROSS. STRONG COLD FRONT CROSSING ON SATURDAY WILL BRING IN
ANOTHER SURGE OF STRONG WINDS...POSSIBLY REACHING 35 KT GALES
SATURDAY AFTN INTO SATURDAY EVENING. LEFT THE GALE WATCH UP AS IT IS
ONLY A MARGINAL SETUP FOR GALES. MID SHIFT CAN MAKE THE FINAL CALL.
DID PUT UP HEAVY FREEZING SPRAY WARNING AS THAT IS MORE CERTAIN.
WINDS BECOME LIGHT BY SUNDAY AS HIGH PRESSURE DRIFTS ACROSS. WINDS
INCREASE FM THE WSW ON MONDAY NIGHT AHEAD OF ANOTHER LOW PRESSURE AND
COLD FRONT THAT SWEEP OVER THE AREA ON TUESDAY NIGHT AND WEDNESDAY.
BEHIND THAT FRONT...ANOTHER PERIOD OF GALES AND HEAVY FREEZING SPRAY
IS EXPECTED INTO THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM NOON SATURDAY TO 5 AM EST
SUNDAY FOR LSZ264-266-267.
GALE WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING FOR
LSZ264-266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
408 PM EST FRI JAN 30 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 406 PM EST FRI JAN 30 2015
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
HUDSON BAY INTO THE NE CONUS RESULTING IN NW FLOW THROUGH THE NRN
GREAT LAKES. AN UPSTREAM SHORTWAVE TROUGH WAS LOCATED OVER SRN
MANITOBA. THE SHRTWV AND ASSOCIATED WAA PATTERN SUPPORTED SOME LIGHT
SNOW FROM FAR NRN MN INTO NW ONTARIO WITH VSBY INTO THE 1-3SM RANGE.
AT THE SFC...A RIDGE EXTENDED FROM THE MID MS VALLEY INTO THE WRN
GREAT LAKES. BACKING WINDS TO SW OVER WRN LAKE SUPERIOR AND W OVER
THE ERN LAKE HAVE PUSHED THE LES BANDS OFFSHORE EXCEPT FOR SOME
LINGERING FLURRIES NEAR GRAND MARAIS.
TONIGHT...EXPECT MID/HIGH CLOUDS TO THICKEN INTO THIS EVENING AS THE
AS THE SHRTWV APPROACHES. UPSTREAM TRENDS AND MODELS FCST 285K-290K
ISENTROPIC LIFT...SUGGESTS THAT THE AREA OF LIGHT SNOW WILL SPREAD
THROUGH UPPER MICHIGAN BTWN 03Z-09Z. WITH LITTLE MOISTURE AVAILABLE
AND DRY LOW LEVELS DELAYING THE ONSET OF THE PCPN...QPF OF 0.05 OR
LOWER WITH SLR VALUES NEAR 20/1 WOULD ONLY RESULT IN SNOW AMOUNTS OF
AN INCH OR LESS. HOWEVER...AS LOW LEVEL CONV INCREASES ALONG THE SFC
FRONT/TROUGH AND 850 MB TEMPS DROP TO AROUND -12C...THERE MAY BE A
BRIEF PERIOD OF LAKE ENHANCED SNOW INTO NW UPPER MI THAT MAY BRING
TOTALS INTO THE 1 TO 2 INCH RANGE.
SAT...THE AREA OF LOW LEVEL CONV WITH THE FRONT WILL SLIDE THROUGH
THE REST OF THE NRN CWA WITH THE POTENTIAL FOR A NARROW BAND OF
MODERATE SNOW. ALTHOUGH 850 MB TEMPS DROP TO NEAR -20C BY 00Z
SUN...A QUICK TRANSITION TO A MORE DIFFLUENT/ANTICYCLONIC LOW-LVL
NORTHERLY FLOW AND FALLING INVERSIONS AT OR BELOW 4KFT WILL LIMIT
LES INTENSITY THE REST OF THE DAY. SNOW ACCUMULATIONS OF ONLY AROUND
AN INCH ARE EXPECTED. AFTER MIDDAY HIGHS RANGING FROM THE TEENS NW
TO MID TO UPPER 20S SCNTRL...TEMPS WILL DURING THE AFTERNOON AS
BRISK N TO NW WINDS USHER ARCTIC AIR MASS INTO THE AREA. GUSTY WINDS
WILL ALSO CREATE BLSN IN OPEN AREAS NEAR LAKE SUPERIOR.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 453 AM EST FRI JAN 30 2015
A COLD PATTERN IS SETTING IN FOR THE LONG TERM PORTION OF THE FCST
FEATURING A W COAST RIDGE AND CNTL/ERN TROF. THE RESULTING NW FLOW
INTO THE GREAT LAKES WILL RESULT IN A STEADY FEED OF CANADIAN AIR.
WHILE IT WILL BE COLD WITH TEMPS BLO TO MUCH BLO NORMAL AT
TIMES...TEMPS WILL NOT BE UNUSUALLY COLD FOR THIS TIME OF YEAR. AS
FOR PCPN...THIS IS TYPICALLY A DRY PATTERN FOR THE UPPER LAKES WITH
LITTLE IN THE WAY OF SYNOPTIC PCPN EXPECTED. THE COLD WILL HOWEVER
LEAD TO PERSISTENT LES OFF LAKE SUPERIOR. MOST THE LES WILL BE ON
THE LIGHT SIDE...BUT THERE MAY BE THE OCCASIONAL BOOST WITH THE
PASSAGE OF SHORTWAVES PROVIDING SOME ENHANCEMENT.
BEGINNING SAT...STRONG SHORTWAVE DRIVING SE THROUGH ONTARIO WILL
PUSH A SFC COLD FRONT ACROSS THE AREA AS WINDS SHIFT NRLY BEHIND THE
FRONT SAT MORNING. THERE COULD BE THE TYPICAL QUICK BURST OF MDT TO
POSSIBLY HVY LAKE ENHANCED SNOW ACCOMPANYING COLD FRONT ONSHORE OVER
MAINLY THE ERN HALF OF THE FCST AREA. ALTHOUGH 850MB TEMPS FALL TO
-20 TO -25C BY 00Z SUN...SHARP TRANSITION TO A MORE
DIFFLUENT/ANTICYCLONIC LOW-LVL NORTHERLY FLOW AND A FALLING
INVERSION TO 4KFT OR LOWER WILL LIMIT LES INTENSITY AFTER THE BURST
OF HEAVIER SNOW ASSOCIATED WITH COLD FROPA. SNOW ACCUMULATIONS SAT
SHOULD BE IN THE 1-2 TO POSSIBLY 3 INCH RANGE. AFTER EARLY HIGHS
RANGING FROM THE TEENS NW TO MID TO UPPER 20S SCNTRL...TEMPS WILL
FALL THRU THE DAY AS BRISK N TO NW WINDS USHER ARCTIC AIR MASS INTO
THE AREA. GUSTY WINDS WILL ALSO CREATE BLSN IN OPEN AREAS NEAR LAKE
SUPERIOR.
SAT NIGHT THRU SUN NIGHT...UPPER MI WILL BE DOMINATED BY ARCTIC AIR
MASS WITH INITIAL NORTHERLY LOW-LEVEL FLOW BACKING WNW BY SUN NIGHT.
INVERSION HGTS PLUNGING BLO 2KFT ESPECIALLY LATE SAT NIGHT INTO
SUNDAY COMBINED WITH LOSS OF DGZ DUE TO THE COLD AIR MASS WILL KEEP
LAKE EFFECT SNOW ACCUMULATIONS ON THE LIGHT SIDE...GENERALLY 1-2
INCHES TO PERHAPS LOCALLY 3 INCHES PER 12HRS. THERE COULD BE A
POTENTIAL FOR A LAND BREEZE TO PUSH OUT OVER LAKE SUPERIOR FROM
AROUND MUNISING EASTWARD LATE SAT NIGHT/SUN MORNING AS PRES
GRADIENT/WINDS SLACKEN. IF THIS HAPPENS...A MESOLOW COULD SPIN UP
OVER SCNTRL LAKE SUPERIOR AND LEAD TO HEAVIER SNOW NEAR THE SHORE
BTWN MARQUETTE AND MUNISING...DEPENDING ON THE CIRCULATION
STRUCTURE. SAT NIGHT COULD BE PARTICULARLY CHILLY OVER THE FAR ERN
CWA IF CLOUDS/LES SHIFT W FROM WINDS BECOMING EASTERLY DUE TO
DRAINAGE OF COLD AIR INTO THAT AREA OFF ONTARIO.
MON...LES WILL BEGIN TO SHIFT OUT OVER LAKE SUPERIOR AS WINDS BACK
DUE TO HIGH PRES SHIFTING FROM THE MID MISSISSIPPI VALLEY TO THE
OHIO VALLEY. BY MON AFTN...LES MAY ONLY BE AFFECTING THE KEWEENAW.
TUE-THU...MEDIUM RANGE GUIDANCE IS TRENDING STRONGER WITH THE NEXT
SHORTWAVE DIVING SE OUT OF CANADA FOR THE MIDDLE OF THE WEEK. LOOKS
LIKE THERE MAY BE THE POTENTIAL FOR WIDESPREAD -SN ACROSS THE FCST
AREA TUE/TUE NIGHT ASSOC WITH THE SHORTWAVE ALONG WITH A PERIOD OF
MORE SIGNIFICANT LAKE ENHANCEMENT NEAR LAKE SUPERIOR. BEHIND THE
SHORTWAVE...MODELS INDICATE A VERY COLD SURGE OF ARCTIC AIR WITH
850MB TEMPS OF -25 TO -30C MOVING OVER THE AREA WED INTO EARLY THU.
WITH DGZ DRIVEN BELOW LAKE SURFACE AND INVERSIONS AT OR BLO 5KFT
SETTING UP BEHIND SHORTWAVE...LES ACCUMULATIONS SHOULD BE LIGHT WED
INTO THU. ALTHOUGH ACCUMULATION SHOULD BE LIGHT...THE VERY COLD AIR
AIRMASS WILL RESULT IN SMALL SNOWFLAKES THAT ARE VERY EFFECTIVE AT
REDUCING VISIBILITY. LOWEST TEMPS OF THE WEEK SHOULD OCCUR WED/THU.
MODELS SUGGEST TEMPS SHOULD MODERATE BY LATE NEXT WEEK (FRI-SAT) AS
AMPLIFIED WRN RDG/ERN TROF PATTERN BEGINS TO BREAK DOWN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1249 PM EST FRI JAN 30 2015
WITH OFFSHORE WINDS...VFR CONDITIONS ARE EXPECTED AT IWD/SAW INTO
THIS EVENING. HOWEVER....LAKE EFFECT CLOUDS AND SNOW SHOWERS WILL
LINGER AT CMX THIS LATE AFTERNOON UNTIL WINDS BACK TO THE SW AND
INCREASE. A PERIOD OF IFR/MVFR VSBY WILL GIVE WAY TO VFR VSBY EVEN
AS THE MVFR CIGS PERSIST. A TROUGH OF LOW PRESSURE NEARING FROM THE W
THAT WILL BRING HIGH CLOUDS ACROSS THE REGION THIS AFTERNOON. THE
TROUGH OVER NW MN AT 00Z/SAT WILL AND CROSS CENTRAL LAKE SUPERIOR BY
12Z. LOOK FOR -SN TO MOVE IN DURING THE EVENING HOURS...AND PICK UP
IN INTENSITY ALONG AND BEHIND THE FRONT. LES AND GUSTY WINDS
PRODUCING BLSN AND LOWER VSBY IS EXPECTED AT CMX BY MID MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 500 AM EST FRI JAN 30 2015
GALES CONTINUE TO DIMINISH...AND HEAVY FREEZING SPRAY WILL COME TO
AN END OVER THE E HALF OF LAKE SUPERIOR BY 15Z TODAY AS LIGHTER
WINDS TAKE HOLD AS HIGH PRESSURE BUILDS INTO THE AREA. THE MAIN HIGH
PRESSURE SYSTEM STRETCHING FROM JUST NW OF LAKE SUPERIOR THROUGH E
MN AND W WI WILL SINK TO THE OH VALLEY TODAY...WHILE EXTENDING A
RIDGE ACROSS LAKE SUPERIOR. LOOK FOR A TROUGH ACROSS THE DAKOTAS
THIS AFTERNOON TO SHIFT ACROSS LAKE SUPERIOR TONIGHT...AND EXIT INTO
SE ONTARIO SATURDAY AFTERNOON. LARGE HIGH PRESSURE ACROSS W AND
CENTRAL CANADA SATURDAY WILL SETTLE ACROSS THE N AND CENTRAL PLAINS
STATES SUNDAY INTO SUNDAY NIGHT. NW GALES OF 35 TO NEAR 40KTS WILL
BE POSSIBLE SATURDAY AFTERNOON...ALONG WITH THE RETURN OF HEAVY
FREEZING SPRAY. LOOK FOR A GALE WATCH TO BE HOISTED LATER THIS
MORNING. EXPECT A RIDGE EXTENDING FROM THIS HIGH ACROSS LAKE
SUPERIOR SUNDAY MORNING TO SLOWLY WEAKEN MONDAY AFTERNOON AS THE
AREA OF HIGH PRESSURE DRIFTS ACROSS THE OH VALLEY...AND THEN THE MID
ATLANTIC STATES ON TUESDAY. A TROUGH WILL THEN CROSS THE UPPER GREAT
LAKES ON TUESDAY. LOOKING FARTHER OUT...HEAVY FREEZING SPRAY WILL
LIKELY RETURN ON WEDNESDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM NOON SATURDAY TO 5 AM EST
SUNDAY FOR LSZ264-266-267.
GALE WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING FOR
LSZ264-266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...VOSS
AVIATION...JLB
MARINE...KF
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
834 PM MST SAT JAN 31 2015
.UPDATE...
SNOWFALL IS SLOWLY DECREASING FROM NORTH TO SOUTH ACROSS OUR
FORECAST AREA. RADAR IS CURRENTLY SHOWING THE BULK OF THE HEAVIEST
SNOW ALONG AND SOUTH OF INTERSTATE 90 FROM REED POINT TO HARDIN
WHERE A FRONTOGENESIS BAND CONTINUES TO LINGER. REPORTS THAT WE
HAVE BEEN RECEIVING SINCE LATE AFTERNOON INDICATE SNOW AMOUNTS IN
THE 4 TO 6 INCH RANGE FROM COLUMBUS TO JOLIET AND RED LODGE. PARK
CITY HAS EVEN COME IN WITH 2 INCHES WITH THE SNOW CONTINUING TO
FALL ACROSS THESE AREAS. VERY ICY ROAD CONDITIONS HAVE ALSO BEEN
REPORTED ALONG INTERSTATE 90 BETWEEN BILLINGS AND REED
POINT...ESPECIALLY THE REED POINT TO COLUMBUS AREA WHERE NUMEROUS
ACCIDENTS HAVE BEEN REPORTED. ALSO...EARLIER THIS
EVENING...TRAFFIC WAS BACKED UP FOR MILES ALONG HIGHWAY 212 NORTH
AND SOUTH BOUND OF SILESIA WITH NO MOVEMENT FOR 90 MINUTES DUE TO
AN ACCIDENT.
IN GENERAL...RADAR TRENDS ARE DECREASING BUT A FEW AREAS OF SNOW
SHOWERS CONTINUE TO DEVELOP AND DISSIPATE WITH THE LATEST INCREASE
IN ACTIVITY JUST NORTH AND EAST OF BILLINGS. FOR THE EVENING
UPDATE...I DID BEGIN TO LOWER POPS ACROSS OUR NORTH TO HIGH CHANCE
AND LOWERED THE CENTRAL AND EAST BUT STILL KEPT LIKELY POPS
THROUGH MIDNIGHT BUT LOWERED THE QPF AND ADDITIONAL SNOW AMOUNTS
FOR THE REMAINDER OF THE EVENING. ADDITIONAL ACCUMULATIONS THIS
EVENING LOOK TO BE 1 TO 2 INCHES ACROSS SOUTHERN STILLWATER COUNTY
INTO CARBON COUNTY ACROSS TO SOUTHERN BIG HORN COUNTY. SNOW
CHANCES DIMINISH CONSIDERABLY AFTER MIDNIGHT WITH JUST A SLIGHT
CHANCE TO CHANCE ACROSS THE FORECAST AREA WITH LITTLE IF ANY
ADDITIONAL ACCUMULATIONS EXPECTED.
AS FOR OVERNIGHT LOWS TONIGHT...CURRENT TEMPERATURES FOR MOST
AREAS ARE NOT TOO FAR FROM FORECASTED LOWS. SATELLITE IS SHOWING
THE CLOUDS THINNING SOMEWHAT UPSTREAM AND LATEST GUIDANCE HAS COME
IN A BIT COLDER WITH TEMPERATURES. AS A RESULT...HAVE LOWERED
FORECASTED LOWS ACROSS THE ENTIRE AREA BY SEVERAL DEGREES. HOOLEY
&&
.SHORT TERM...VALID FOR SUN AND MON...
SNOW THROUGH THIS EVENING IS THE MAIN SHORT TERM FORECAST CONCERN
AS ROADS WILL BE SLIPPERY IN PLACES...ESPECIALLY AFTER SUNSET.
SNOW RAPIDLY FILLED IN AND INTENSIFIED OVER MUCH OF SOUTHERN MT
EARLY THIS AFTERNOON AS THE PEAK OF THE FORCING TIED TO THE MID-
AND UPPER-LEVEL SHORTWAVE TROUGH BEGAN TO CROSS THE AREA. WE FEEL
THE SNOW WILL WIND DOWN DURING THE EVENING AS THAT FORCING EXITS
STAGE RIGHT INTO THE DAKOTAS...BUT RECENT HIGH-RESOLUTION MODEL
GUIDANCE AND THE COARSER 12 UTC GFS AND TO A LESSER EXTENT THE
ECMWF STILL SUPPORT EVENT TOTALS OF 1 TO 2 INCHES IN MANY SPOTS BY
EVENING. WE WERE SOMEWHAT CONCERNED ABOUT HIGHER-THAN-EXPECTED
SNOW TOTALS IN AND NEAR BILLINGS GIVEN RADAR TRENDS THROUGH 2130
UTC...WHICH HAD AN OROGRAPHIC SNOW BAND FROM LAVINA TO BROADVIEW
AND DOWNSTREAM TO THE METRO AREA. A MORE CONTEMPORARY TREND IN
RADAR DATA IS FOR THAT BAND TO DIMINISH THOUGH...WHICH IS A TREND
SUPPORTED BY THE DEPARTURE OF LARGER-SCALE FORCING ALOFT. WE HAVE
THUS STAYED THE COURSE WITH THE IDEA THAT TOTAL SNOW ACCUMULATION
IN BILLINGS WILL BE AN INCH OR LESS. AFTERNOON RADAR IMAGERY ALSO
ALSO SUPPORTED TODAY/S HRRR AND HIGH-RESOLUTION WRF-NMM AND WRF-
ARW RUNS FOR A MODEST UPSLOPE-AIDED ENHANCEMENT OF SNOW IN THE
RED LODGE FOOTHILLS WHERE WE ARE NOW CALLING FOR 2 TO 3 INCHES OF
SNOW THROUGH THIS EVENING.
DESPITE RELATIVELY LOW SNOW AMOUNTS PRECLUDING US FROM ISSUING ANY
HEADLINES FOR THIS EVENT...ROADS WILL BECOME SLIPPERY BY EVENING
IN AREAS WHERE THEY AREN/T ALREADY AS THE LACK OF SOLAR RADIATION
AFTER SUNSET WILL ALLOW ROAD SURFACES TO DROP BELOW FREEZING AND
ANY MOISTURE ON THEM TO FREEZE. THAT IS OUR MAIN FORECAST MESSAGE.
BY SUNDAY...FLOW ALOFT TURNS ANTICYCLONIC WHILE SHORTWAVE RIDGING
MOVES OVERHEAD AND THAT WILL LEAD TO A DRY DAY WITH HIGHS POSSIBLY
HELD A BIT LOWER THAN THEY WOULD BE OTHERWISE BY FRESH SNOW COVER.
THE 12 UTC MODEL SUITE REMAINED CONSISTENT IN SHOWING A WARM FRONT
MOVING EASTWARD ACROSS THE REGION SUNDAY NIGHT INTO MONDAY AND WE
ARE CARRYING SOME POPS IN THE FORECAST WITH THAT FEATURE...THOUGH
FORCING LOOKS WEAK AND WILL LIKELY BE GREATEST IN SOUTHEASTERN MT
TO THE EAST OF BILLINGS ON MONDAY MORNING WHERE WARM AIR ADVECTION
ALOFT WILL BE FOCUSED.
HIGHS MONDAY WILL JUMP BACK UP WELL INTO THE 40S F ON THE WARM
SIDE OF THAT FRONT IN SOUTH CENTRAL MT AND NORTH CENTRAL WY. ITS
PLACEMENT IS UNCLEAR THOUGH...AND BECOMES EVEN MORE UNCERTAIN COME
MONDAY NIGHT WHEN IT IS LIKELY TO WAFFLE BACK SOUTHWARD AGAIN /AT
LEAST BY THE 12 UTC GFS AND ECMWF...NOT THE NAM/. WE USED A BLEND
OF CONTINUITY AND THE FORMER TWO MODELS TO LEAVE SOME HIGH-CHANCE
TO LOW-END LIKELY POPS IN THE FORECAST BY LATE MONDAY NIGHT ACROSS
PARTS OF THE AREA SINCE THE FRONTAL ZONE COULD FAVOR PRODUCTION OF
SOME LIGHT SNOW. SCHULTZ
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
DID MAKE SOME CHANGES TO THE EXTENDED FORECAST...AND THE
CONCENTRATION OF THESE WERE IN THE EARLIER PART OF THE PERIOD.
NORTHWEST FLOW IS PROGGED OVER THE AREA...WITH A STRONG SHORTWAVE
ROTATING INTO NORTH DAKOTA TUESDAY AND TUESDAY NIGHT. THIS WILL
PUSH A REINFORCING SHOT OF COLD AIR INTO THE AREA. MODELS HAVE
BACKED OFF SOME ON THE DEPTH OF THE COLD AIR AND THUS GUIDANCE WAS
WARMER. THE BULK OF THE COLDER AIR WAS SHOVED TO THE EAST. BUMPED
TEMPERATURES UP A BIT BASED ON BASED ON MODEL TRENDS FOR TUESDAY
AND MAINTAINED ON WEDNESDAY.
MODELS WERE DIFFERENT ON QPF SOLUTIONS AS THE GFS WAS WETTER
EARLIER THAN THE ECMWF AND THE ECMWF HOLDING ONTO PRECIPITATION
LONGER INTO WEDNESDAY. BUMPED POPS FOR TUESDAY AS LOOKS GOOD FOR
AN OVERRUNNING EVENT MONDAY NIGHT INTO TUESDAY NIGHT WITH A DECENT
BAROCLINIC ZONE INVOLVED AND SOME PACIFIC MOISTURE AVAILABLE.
SHOULD THE ECMWF VERIFY...MAY HAVE TO RAISE POPS INTO WEDNESDAY
AND THURSDAY WITH PERSISTENT MID LEVEL WARM ADVECTION. LEFT THE
REST OF THE FORECAST IN TACT AS AN UPPER RIDGE BUILDS IN FOR THE
END OF THE WEEK WITH WEAK ENERGY RIDING OVER THE TOP. WINDS COULD
BECOME STRONG AT LIVINGSTON AND NYE THURSDAY AND THURSDAY NIGHT AS
ENERGY FLATTENS THE RIDGE. TWH
&&
.AVIATION...
ANY LINGERING SNOW THIS EVENING WILL BE CLOSE TO MOUNTAIN
LOCATIONS ACROSS SOUTH CENTRAL MT AND NORTHERN WY...INCLUDING
KSHR...WITH LOCAL IFR/LIFR CONDITIONS. OTHERWISE...MOSTLY MVFR/VFR
CONDITIONS WILL PREVAIL INTO SUNDAY. WE WILL BE MONITORING THE
POTENTIAL FOR SOME LOCALIZED FOG IN SOME AREAS...INCLUDING KBIL.
FRIEDERS
&&
.PRELIMINARY POINT TEMP/POPS...
SUN MON TUE WED THU FRI SAT
-----------------------------------------------------------
BIL 012/031 029/046 028/030 015/033 026/045 036/053 038/056
60/B 21/E 55/J 52/J 21/B 01/N 11/N
LVM 014/040 031/049 035/035 021/039 029/049 036/054 039/055
30/B 31/N 44/W 43/W 21/E 11/N 21/N
HDN 010/030 023/043 024/028 008/032 018/043 030/051 030/054
60/B 22/S 55/J 42/J 21/B 01/B 11/B
MLS 005/023 020/034 018/019 000/023 012/038 025/046 027/052
61/B 24/O 65/J 20/B 11/B 11/B 12/W
4BQ 007/027 022/043 025/026 007/030 019/044 029/054 034/058
71/B 23/O 54/J 31/B 11/B 01/B 12/W
BHK 003/018 013/032 016/016 000/020 012/036 025/045 028/050
71/B 24/S 54/J 20/B 10/B 11/B 12/W
SHR 012/028 021/046 025/027 013/032 020/044 029/055 031/055
61/B 21/E 22/J 52/J 11/B 00/B 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
938 PM CST SAT JAN 31 2015
.UPDATE...
ISSUED AT 920 PM CST SAT JAN 31 2015
WINTER HAS RETURNED. AS EXPECTED...00Z SUBJECTIVE UPPER AIR
ANALYSIS REVEALED A SIGNIFICANT AMOUNT OF MOISTURE WITH PW VALUES
ABOUT 210-280% ABOVE NORMAL. 500MB HEIGHT FALLS RANGED FROM 40 TO
80 METERS ACROSS THE REGION...AND OVERALL THE AREA REMAINS WITHIN
THE ENTRANCE REGION OF A BROAD UPPER LEVEL JET STREAK TO OUR
NORTH.
SNOW CONTINUES AT THIS TIME...AND WILL DO SO THROUGH MOST OF
SUNDAY...ALTHOUGH THE INTENSITY WILL BE WINDING DOWN ON SUNDAY.
THE SNOW SO FAR HAS BEEN A VERY HEAVY WET SNOW WITH SNOWFALL
RATIOS WELL BELOW 10:1. TEMPS HAVE REMAINED JUST ABOVE FREEZING IN
MOST AREAS THIS EVENING...WHICH IS LIKELY CONTRIBUTING TO ROAD
CONDITIONS BECOMING HAZARDOUS...PERHAPS MORESO THAN EXPECTED.
WHILE WINDS REMAIN LIGHT CURRENTLY LESS THAN 10 KNOTS IN MOST
AREAS...THEY ARE BACKING AND BEGINNING TO INCREASE IN NORTHEAST
NEBRASKA AS LOW PRESSURE BEGINS TO MOVE THROUGH CENTRAL KANSAS.
WINDS WILL SUBSTANTIALLY INCREASE BY 12Z AS THE LOW PRESSURE
CENTER MOVES ACROSS THE KC AREA...WHICH WILL THEN CREATE AREAS OF
BLOWING SNOW.
REGARDING SNOWFALL AMOUNTS...WE CURRENTLY HAVE 5 TO 9 INCHES
FORECAST WITH HIGH END WINTER WEATHER ADVISORIES AND WARNINGS IN
EFFECT AND THAT TREND SEEMS OK. THE HEAVY WET SNOW IS COMPACTING
QUITE A BIT ON THE GROUND. HAVE UPPED AMOUNTS JUST SLIGHTLY BASED
ON REPORTS. THUS...THIS WILL LIKELY END UP ON THE HIGH END OF THE
ADVISORY CATEGORY. HAVE ALSO CONSIDERED UPGRADING TO A WINTER
STORM WARNING TO ACCOUNT FOR THE BLOWING SNOW THAT WILL BE TAKING
PLACE ON SUNDAY...WITH GUSTS EASILY APPROACHING 40 MPH. WILL HAVE
TO SEE HOW VISIBILITIES RESPOND TO THAT AS IT MAY END UP IN NEAR
BLIZZARD CONDITIONS IN OUTLYING REMOTE AREAS ACROSS EASTERN
NEBRASKA. WILL DEFER THAT TO THE NEXT FORECAST ONCE WE GET MORE
MODEL DATA IN.
AS A SIDE NOTE...WE WILL BREAK WATER EQUIVALENT RECORDS AT BOTH
LINCOLN AND OMAHA FOR JAN 31.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 325 PM CST SAT JAN 31 2015
SNOW AND HEADLINES ARE THE MAIN PROBLEMS IN THE SHORT TERM AND HAVE
KEPT PRIMARY FOCUS IN THE NEXT 24-30 HOURS.
A 90 KNOT JET MAX WAS ON THE FRONT SIDE OF THE TROUGH ACROSS THE
SOUTHWEST US AT 12Z. ANOTHER AREA OF STRONG WINDS AT 300 MB WAS FROM
NORTHERN MINNESOTA INTO THE OHIO VALLEY. LATEST WATER VAPOR IMAGERY
AND RECENT RAP MODEL INITIALIZATIONS SHOW A CLOSED LOW DROPPING
SOUTHWARD ACROSS BAJA. A MID LEVEL TROUGH WAS LOCATED FROM WESTERN
NEBRASKA INTO EASTERN COLORADO AND ANOTHER WAVE WAS DROPPING
SOUTHEAST FROM MONTANA. A 12 HOUR 500 MB HEIGHT FALL MAX OF ABOUT
130 METERS WAS OVER MONTANA AND ANOTHER AROUND 100 METERS WAS NEAR
THE MEXICO/NEW MEXICO BORDER. SO THIS IS A FAIRLY COMPLEX SETUP...
WITH SOME PHASING OF THE NORTHERN AND SOUTHERN STREAMS EXPECTED
TONIGHT.
MOISTURE HAS BEEN RETURNING OVER THE CENTRAL PLAINS WITH AREAS OF
SNOW OR A MIX OF RAIN AND SNOW. WILL MAKE SOME MINOR CHANGES TO
HEADLINES...ADDING A FEW COUNTIES TO THE WARNING IN THE NORTH.
IMPRESSIVE MOISTURE (850-700 MB SPECIFIC HUMIDITY VALUES 3-4 G/KG
AT 6 PM THIS EVENING...FALLING TO 2-3 G/KG BY 12Z SUNDAY) ALONG
WITH GOOD FORCING SHOULD ALLOW FOR SNOW AMOUNTS FROM ABOUT 4 TO 9
INCHES IN MOST OF THE FORECAST AREA. HIGHEST SNOW AMOUNTS EXPECTED
NORTH AND EAST. AS COLDER AIR SINKS IN FROM THE NORTH BEHIND THE
COLD FRONT (WHICH EXTENDED FROM WISCONSIN BACK INTO SOUTHWEST
NEBRASKA EARLY THIS AFTERNOON)...TEMPERATURES WILL FALL AND ROADS
WILL START TO ICE UP/BECOME SNOW COVERED AND SLICK. TEMPERATURES
SHOULD START SLIDING TONIGHT AND CONTINUE TO DROP THROUGH MUCH OF
THE DAY SUNDAY. STRONG NORTH SURFACE WINDS WILL LIKELY ALSO CAUSE
SOME BLOWING SNOW LATER TONIGHT AND AT LEAST THROUGH EARLY SUNDAY
AFTERNOON.
HEADLINES WILL CONTINUE UNTIL 6 PM SUNDAY IN NEBRASKA AND UNTIL 9 PM
SUNDAY IN SOUTHWEST IOWA. IT IS POSSIBLE THESE MAY BE CANCELLED
EARLIER THAN THAT...BUT THAT IS WHAT WE WILL GO WITH FOR NOW.
SNOW AMOUNTS WILL DECREASE THROUGH THE DAY AS DRIER AIR MOVES IN
FROM THE WEST AND LIFT PULLS OUT OF THE REGION. HIGH PRESSURE AT
THE SURFACE BUILDS IN FOR SUNDAY NIGHT. WINDS WILL DECREASE AND
WITH CLEARING SKIES HAVE LOWS FALLING OR AROUND ZERO...OR EVEN
BELOW ZERO IN OUR NORTHERN COUNTIES. WARM AIR ADVECTION AND SOUTH
WINDS SHOULD INCREASE MONDAY. KEPT A SMALL CHANCE OF SNOW NORTH
AND NORTHEAST OF OMAHA...BUT NOT A BIG DEAL. A SLIGHTLY BETTER
CHANCE OF SNOW ARRIVES FOR TUESDAY. 12Z GFS SEEMED A BIT TOO HIGH
ON QPF TUESDAY...BUT WILL SEE HOW THINGS TREND NEXT FEW MODEL
RUNS.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 325 PM CST SAT JAN 31 2015
LOOK FOR MODERATING TEMPERATURES THIS PERIOD. FAST WEST/NORTHWEST
MID LEVEL FLOW WILL OCCUR EARLY...WITH A RIDGE DEVELOPING OVER THE
WESTERN US. THIS RIDGE SHOULD BUILD EAST THROUGH THE WEEK. HIGHS
WILL BE 20S WEDNESDAY AND THURSDAY RISING TO ABOVE NORMAL FOR
FRIDAY AND SATURDAY. THERE IS SOME CHANCE OF LIGHT SNOW WEDNESDAY
OTHERWISE IT SHOULD BE MAINLY DRY.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 518 PM CST SAT JAN 31 2015
WINTER EVENT WILL IMPACT THE TAF SITES THROUGH MOST OF THE PERIOD.
IFR AND OCCASIONALLY LIFR CONDITIONS WITH SNOW AT ALL TAF SITES
WITH VISIBILITIES RANGING FROM 1/2 TO 1 1/2 MILES MOSTLY. WINDS
REMAIN LIGHT FROM THE EAST OR SOUTHEAST INITIALLY. WINDS WILL
CONTINUE TO BACK BECOMING NORTHEAST...THEN NORTH AND SUBSTANTIALLY
INCREASING BY 11-13Z TO 22 TO 35 KNOTS. AT THAT TIME...SNOW AND
BLOWING SNOW WILL CONTINUE TO REDUCE VISIBILITY THROUGH MUCH OF
THE DAY SUNDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 6 PM CST SUNDAY FOR NEZ011-016-017-
030>033-042>045-050>053-065>068-078-088>093.
WINTER STORM WARNING UNTIL 6 PM CST SUNDAY FOR NEZ012-015-018-
034.
IA...WINTER STORM WARNING UNTIL 9 PM CST SUNDAY FOR IAZ043-055-056-
069-080-091.
WINTER WEATHER ADVISORY UNTIL 6 PM CST SUNDAY FOR IAZ079-090.
&&
$$
UPDATE...DEWALD
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
524 PM CST SAT JAN 31 2015
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 325 PM CST SAT JAN 31 2015
SNOW AND HEADLINES ARE THE MAIN PROBLEMS IN THE SHORT TERM AND HAVE
KEPT PRIMARY FOCUS IN THE NEXT 24-30 HOURS.
A 90 KNOT JET MAX WAS ON THE FRONT SIDE OF THE TROUGH ACROSS THE
SOUTHWEST US AT 12Z. ANOTHER AREA OF STRONG WINDS AT 300 MB WAS FROM
NORTHERN MINNESOTA INTO THE OHIO VALLEY. LATEST WATER VAPOR IMAGERY
AND RECENT RAP MODEL INITIALIZATIONS SHOW A CLOSED LOW DROPPING
SOUTHWARD ACROSS BAJA. A MID LEVEL TROUGH WAS LOCATED FROM WESTERN
NEBRASKA INTO EASTERN COLORADO AND ANOTHER WAVE WAS DROPPING
SOUTHEAST FROM MONTANA. A 12 HOUR 500 MB HEIGHT FALL MAX OF ABOUT
130 METERS WAS OVER MONTANA AND ANOTHER AROUND 100 METERS WAS NEAR
THE MEXICO/NEW MEXICO BORDER. SO THIS IS A FAIRLY COMPLEX SETUP...
WITH SOME PHASING OF THE NORTHERN AND SOUTHERN STREAMS EXPECTED
TONIGHT.
MOISTURE HAS BEEN RETURNING OVER THE CENTRAL PLAINS WITH AREAS OF
SNOW OR A MIX OF RAIN AND SNOW. WILL MAKE SOME MINOR CHANGES TO
HEADLINES...ADDING A FEW COUNTIES TO THE WARNING IN THE NORTH.
IMPRESSIVE MOISTURE (850-700 MB SPECIFIC HUMIDITY VALUES 3-4 G/KG
AT 6 PM THIS EVENING...FALLING TO 2-3 G/KG BY 12Z SUNDAY) ALONG
WITH GOOD FORCING SHOULD ALLOW FOR SNOW AMOUNTS FROM ABOUT 4 TO 9
INCHES IN MOST OF THE FORECAST AREA. HIGHEST SNOW AMOUNTS EXPECTED
NORTH AND EAST. AS COLDER AIR SINKS IN FROM THE NORTH BEHIND THE
COLD FRONT (WHICH EXTENDED FROM WISCONSIN BACK INTO SOUTHWEST
NEBRASKA EARLY THIS AFTERNOON)...TEMPERATURES WILL FALL AND ROADS
WILL START TO ICE UP/BECOME SNOW COVERED AND SLICK. TEMPERATURES
SHOULD START SLIDING TONIGHT AND CONTINUE TO DROP THROUGH MUCH OF
THE DAY SUNDAY. STRONG NORTH SURFACE WINDS WILL LIKELY ALSO CAUSE
SOME BLOWING SNOW LATER TONIGHT AND AT LEAST THROUGH EARLY SUNDAY
AFTERNOON.
HEADLINES WILL CONTINUE UNTIL 6 PM SUNDAY IN NEBRASKA AND UNTIL 9 PM
SUNDAY IN SOUTHWEST IOWA. IT IS POSSIBLE THESE MAY BE CANCELLED
EARLIER THAN THAT...BUT THAT IS WHAT WE WILL GO WITH FOR NOW.
SNOW AMOUNTS WILL DECREASE THROUGH THE DAY AS DRIER AIR MOVES IN
FROM THE WEST AND LIFT PULLS OUT OF THE REGION. HIGH PRESSURE AT
THE SURFACE BUILDS IN FOR SUNDAY NIGHT. WINDS WILL DECREASE AND
WITH CLEARING SKIES HAVE LOWS FALLING OR AROUND ZERO...OR EVEN
BELOW ZERO IN OUR NORTHERN COUNTIES. WARM AIR ADVECTION AND SOUTH
WINDS SHOULD INCREASE MONDAY. KEPT A SMALL CHANCE OF SNOW NORTH
AND NORTHEAST OF OMAHA...BUT NOT A BIG DEAL. A SLIGHTLY BETTER
CHANCE OF SNOW ARRIVES FOR TUESDAY. 12Z GFS SEEMED A BIT TOO HIGH
ON QPF TUESDAY...BUT WILL SEE HOW THINGS TREND NEXT FEW MODEL
RUNS.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 325 PM CST SAT JAN 31 2015
LOOK FOR MODERATING TEMPERATURES THIS PERIOD. FAST WEST/NORTHWEST
MID LEVEL FLOW WILL OCCUR EARLY...WITH A RIDGE DEVELOPING OVER THE
WESTERN US. THIS RIDGE SHOULD BUILD EAST THROUGH THE WEEK. HIGHS
WILL BE 20S WEDNESDAY AND THURSDAY RISING TO ABOVE NORMAL FOR
FRIDAY AND SATURDAY. THERE IS SOME CHANCE OF LIGHT SNOW WEDNESDAY
OTHERWISE IT SHOULD BE MAINLY DRY.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 518 PM CST SAT JAN 31 2015
WINTER EVENT WILL IMPACT THE TAF SITES THROUGH MOST OF THE PERIOD.
IFR AND OCCASIONALLY LIFR CONDITIONS WITH SNOW AT ALL TAF SITES
WITH VISIBILITIES RANGING FROM 1/2 TO 1 1/2 MILES MOSTLY. WINDS
REMAIN LIGHT FROM THE EAST OR SOUTHEAST INITIALLY. WINDS WILL
CONTINUE TO BACK BECOMING NORTHEAST...THEN NORTH AND SUBSTANTIALLYINCREASING
BY 11-13Z TO 22 TO 35 KNOTS. AT THAT TIME...SNOW AND BLOWING SNOW
WILL CONTINUE TO REDUCE VISIBILITY THROUGH MUCH OF THE DAY SUNDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 6 PM CST SUNDAY FOR NEZ011-016-017-
030>033-042>045-050>053-065>068-078-088>093.
WINTER STORM WARNING UNTIL 6 PM CST SUNDAY FOR NEZ012-015-018-
034.
IA...WINTER STORM WARNING UNTIL 9 PM CST SUNDAY FOR IAZ043-055-056-
069-080-091.
WINTER WEATHER ADVISORY UNTIL 6 PM CST SUNDAY FOR IAZ079-090.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
310 PM CST FRI JAN 30 2015
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 310 PM CST FRI JAN 30 2015
PCPN TYPE AND PCPN AMOUNTS WILL BE THE MAIN CONCERN IN THIS PERIOD...
ESPECIALLY FROM LATE TONIGHT INTO SATURDAY EVENING. PCPN SHOULD TURN
TO MOSTLY SNOW BY LATE SATURDAY NIGHT ALL AREAS.
WATER VAPOR LOOP AND LATEST RAP MODEL INITIALIZATIONS SHOWED A
CLOSED LOW OVER THE CALIFORNIA/ARIZONA BORDER REGION EARLY THIS
AFTN. THIS WILL DROP SOUTHWARD INTO MEXICO THROUGH SUNDAY. SOME
SHORTWAVE ENERGY WILL MOVE NORTHEAST OUT OF THIS TROUGH THOUGH AND
MOVE UP INTO THE CENTRAL PLAINS LATER TONIGHT AND SATURDAY. SURFACE
ANALYSIS EARLY THIS AFTERNOON SHOWED MODEST SOUTH/SOUTHWEST WINDS
SPREADING ACROSS OUR AREA. CLOUDS WILL THICKEN AND LOWER...WITH
LIGHT PCPN PROBABLY MOVING INTO OUR SOUTHERN COUNTIES BEFORE 12Z.
HAVE LOWS FORECAST IN THE UPPER 20S NORTH AND LOWER 30S SOUTH. THE
PCPN TYPE MAY BE A MIX LATER TONIGHT INTO SATURDAY.
DID MAKE SOME MODIFICATIONS TO SNOW AMOUNTS...MAINLY FOR SATURDAY
NIGHT INTO SUNDAY MORNING. ON SATURDAY...IT APPEARS THAT IF WE GET
ANY ACCUMULATIONS...THEY WOULD BE LIGHT AND MAINLY ON GRASSY AREAS
FOR OUR SOUTHERN ZONES. FARTHER NORTH...PCPN CHANCES WILL BE
INCREASING IN THE AFTERNOON BUT AMOUNTS WOULD BE LIGHTER. THE NAM
FORECAST SOUNDINGS STILL APPEARED TOO COLD...AND WENT CLOSER TO A
BLEND OF SOME OF THE OTHER MODELS...ESPECIALLY THE SREF. NORTH
WINDS WILL SPREAD ACROSS THE AREA SATURDAY NIGHT...AND AS THE
COLUMN COOLS...PCPN WILL CHANGE TO MOSTLY SNOW AND WILL START TO
ACCUMULATE. A SEPARATE SYSTEM WILL DROP QUICKLY SOUTHEAST IN THE
NORTHWEST FLOW SATURDAY NIGHT...PROVIDING GOOD LIFT IN A FAVORABLE
ENVIRONMENT FOR SNOW FROM THE NORTHERN PARTS OF NORTHEAST NEBRASKA
INTO WEST CENTRAL IOWA. INCREASED SNOW AMOUNTS FOR AREAS ALONG AND
NORTH OF HIGHWAY 20. IT APPEARS ANOTHER LOBE OF LIFT WILL DROP
DOWN OVER PARTS OF THE AREA SUNDAY AFTERNOON...SO KEPT SOME
MENTION OF LIGHT SNOW GOING UNTIL SUNDAY NIGHT. SUNDAY NIGHT IS
EXPECTED TO BE COLD WITH DECREASING CLOUDS AND DECREASING WINDS.
LOWS SHOULD DROP TO THE SINGLE DIGITS AND WE MAY SEE SOME BELOW
ZERO NUMBERS FROM HARTINGTON AND WAYNE TOWARD TEKAMAH AND HARLAN.
FAST NORTHWEST FLOW IN THE MID LEVELS WILL BE IN PLACE FOR MONDAY
AND IT DOES APPEAR THAT A SHORTWAVE TROUGH COULD MOVE THROUGH OUR
AREA. MODELS...ESPECIALLY THE 12Z GFS...BRING SOME LIGHT SNOW IN
FOR MONDAY AFTERNOON. COULD NOT ARGUE WITH THAT TOO MUCH SO WENT
WITH A SLIGHT CHANCE OF LIGHT SNOW FOR NOW AND WILL FINE TUNE THAT
LATER. MEASURABLE LIGHT AMOUNTS SEEM POSSIBLE...ESPECIALLY IN
WESTERN IOWA MONDAY. HIGHS MONDAY WILL BE MOSTLY 20S.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 310 PM CST FRI JAN 30 2015
SOME MILDER AIR WILL SPREAD IN BRIEFLY FOR TUESDAY...WITH HIGHS
REACHING THE UPPER 30S AND LOWER 40S. DID NOT WANT TO GET TOO
OPTIMISTIC AT THIS POINT FOR HIGHS. ANOTHER SURGE OF COLDER AIR
WILL DROP DOWN INTO THE AREA BY TUESDAY NIGHT. SOME LIGHT SNOW
SEEMS POSSIBLE BASED ON THE PATTERN...PLUS BOTH THE 12Z GFS AND
ECMWF SHOW A BIT OF SNOW.
TEMPERATURES WEDNESDAY AND THURSDAY WILL BE BELOW NORMAL...THEN
CLOSER TO NORMAL BY FRIDAY AS SOUTH OR SOUTHWEST WINDS INCREASE.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1138 AM CST FRI JAN 30 2015
VFR CONDITIONS ARE EXPECTED DURING THE FIRST FEW HOURS OF THE TAF
CYCLE. A STRONG SYSTEM WILL BE MOVING NORTHEAST INTO THE REGION
BRINGING INCREASING MOISTURE AND A CHANCE OF PRECIPITATION TOWARD
THE END OF THIS CYCLE. CLOUDS WILL INCREASE OVERNIGHT FROM THE
SOUTHWEST WITH MVFR CONDITIONS SPREADING NORTHEAST BEFORE 12Z.
PCPN SHOULD MOVE INTO KLNK FIRST AROUND 13-18Z....WITH KOMA
FOLLOWING AROUND 16-18Z. PCPN TYPE THROUGH 18Z SHOULD MAINLY BE
-RA.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM/TONIGHT...KERN
SHORT TERM/SATURDAY THRU MONDAY...MILLER
LONG TERM...MILLER
AVIATION...KERN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1142 PM CST THU JAN 29 2015
.SHORT TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 315 PM CST THU JAN 29 2015
PCPN AMOUNTS AND PCPN TYPE WILL PROVIDE THE MAIN FORECAST CHALLENGES
IN THIS PERIOD. MODELS HAVE SETTLED SOMEWHAT AND NOW SUGGEST AT
LEAST OUR SOUTHERN COUNTIES COULD GET SOME SNOW ACCUMULATION.
TONIGHT...SURFACE RIDGE AXIS WILL BUILD INTO THE AREA WITH NORTH
WINDS DECREASING AND EVEN SWITCHING BACK TO THE SOUTH LATE TONIGHT
IN OUR WESTERN ZONES. CLOUD COVER WAS STILL RATHER EXTENSIVE AT 3 PM
ALONG AND EAST OF HIGHWAY 81. EXPECT THAT WE WILL CONTINUE TO SEE A
DECREASE IN CLOUDINESS AT LEAST ON THE WESTERN EDGE. LATEST RUNS OF
THE RAP AND NAM SUGGEST SOME LOW CLOUDS MAY LINGER BASED ON 925 MB
RELATIVE HUMIDITY PROGS. IF CLOUDS CAN AT LEAST SCATTER OUT LATER
TONIGHT AS EXPECTED...WE SHOULD SEE LOWS IN THE UPPER TEENS TO
AROUND 20 DEGREES.
SOUTHERLY WINDS WILL INCREASE INTO THE 10 TO 20 MPH RANGE WITH SOME
HIGHER GUSTS ON FRIDAY. WINDS MAY GET INTO THE 15 TO 25 MPH RANGE
IN NORTHEAST NEBRASKA. EXPECT TEMPERATURES TO TOP OUT IN THE 40S.
MOISTURE AND CLOUDS SHOULD INCREASE FRIDAY NIGHT. A COLD FRONT WILL
BE SINKING INTO OUR NORTHERN ZONES AFTER MIDNIGHT WITH SOME COOLER
AIR THERE...BUT TEMPERATURES IN THE SOUTH SHOULD STAY MOSTLY NEAR
OR ABOVE FREEZING. HAVE INCREASED POPS A BIT FOR FRIDAY NIGHT IN
SOUTHEAST NEBRASKA BUT IT DOES NOT LOOK LIKE THERE WOULD BE ANY
SNOW ACCUMULATION IN THAT PERIOD. WILL NEED TO CLOSELY FOLLOW THE
SOUTHWARD PROGRESS OF THE COLDER AIR. IF SURFACE TEMPERATURES
CAN DROP BELOW FREEZING...THERE WILL BE SOME POTENTIAL FOR LIGHT
FREEZING RAIN.
BEST DYNAMICS WILL STAY SOUTH OF OUR AREA SATURDAY...BUT USING A
COMBINATION OF RECENT RUNS OF THE SREF...GFS AND ECMWF SUGGESTS
THAT AT LEAST PARTS OF OUR AREA WILL SEE SOME SNOW ACCUMULATION.
THE NAM FORECAST SOUNDINGS SEEMED TO COLD AND THUS SEEMED TO
PRODUCE TOO MUCH SNOW. AS THE COLD AIR DEEPENS SATURDAY NIGHT AND
DARKNESS SETS IN...PCPN SHOULD TREND TOWARD ALL SNOW. A MODEST
AREA OF UPPER LEVEL FORCING SHOULD TRACK OVER OUR AREA FROM THE
NORTHWEST SATURDAY NIGHT. A MIX OF RAIN AND SNOW MAY CONTINUE OVER
THE SOUTHEAST CORNER OF NEBRASKA AND IN FAR SOUTHWEST IOWA EARLY
IN THE EVENING. DETAILS ON PCPN TYPE WILL BE CRITICAL FOR ACTUAL
SNOW ACCUMULATIONS AND THERE IS STILL PLENTY OF UNCERTAINTY AT
THIS TIME.
IT APPEARS THAT THE PRIMARY LIFT WILL BE EXITING THE AREA SUNDAY
AFTERNOON...BUT HELD ONTO SOME SLIGHT CHANCES IN CASE THE SYSTEM
SLOWS DOWN A BIT. CURRENT THINKING ON POTENTIAL SNOW AMOUNTS...
AND THE KEY WORD IS POTENTIAL...IS FOR AROUND 2 INCHES OR MORE
ALONG AND SOUTHEAST OF A LINE FROM LINCOLN TO OMAHA...POSSIBLY
APPROACHING 3 TO 4 INCHES NEAR THE MISSOURI BORDER. THESE WOULD BE
TOTAL AMOUNTS FOR THE WHOLE EVENT. TEMPERATURES WILL TURN COLDER
FOR SUNDAY WITH BRISK NORTH WINDS.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 315 PM CST THU JAN 29 2015
A BRIEF AND SMALL WARMUP MAY OCCUR TUESDAY WITH HIGHS IN THE 30S
NORTH TO LOWER 40S SOUTH...BUT IN GENERAL THIS PERIOD WILL HAVE
BELOW NORMAL TEMPERATURES. LOOK FOR HIGHS MAINLY IN THE MID 20S TO
MID 30S WITH LOWS IN THE SINGLE DIGITS AND TEENS. HAVE GONE WITH
SOME SMALL CHANCES FOR LIGHT SNOW FOR PARTS OF THE AREA FROM
MONDAY NIGHT INTO TUESDAY NIGHT...BUT BEST POTENTIAL IS DURING THE
DAY TUESDAY. AMOUNTS WOULD BE AN INCH OR LESS THE WAY THINGS LOOK
RIGHT NOW.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1138 PM CST THU JAN 29 2015
THE BAND OF LOW CLOUDS HAS THINNED THROUGH THE EVENING WITH JUST A
FEW SCT FL025 LEFT. LIGHT AND VARIABLE WINDS AND CLEAR SKIES MAY
LEAD TO SOME LIGHT FOG OR HAZE. THE WINDS ALOFT ARE A LITTLE MORE
MIXED ALONG THE MISSOURI RIVER...BUT DROP OFF AT KOFK AND KLNK SO
MAY NEED TO ADD SOME PATCHY FOG. HIGH CLOUDS WILL BE ON THE
INCREASE DURING THE DAY FRIDAY. SOUTH WINDS INCREASE THURSDAY AT
10 TO 15KT AND A LITTLE STRONG WIND GUSTS AT KOFK.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
309 PM EST FRI JAN 30 2015
.SYNOPSIS...
VERY COLD AIR WILL CONTINUE TO POUR INTO THE REGION TONIGHT...WITH
LAKE-EFFECT SNOW PERSISTING DOWNWIND FROM THE FINGER LAKES...AND
BITTERLY COLD WIND CHILLS AREA-WIDE. COLD TEMPERATURES WILL LAST
THROUGH THE UPCOMING WEEKEND...WITH ONLY A FEW FLURRIES FORESEEN
FROM SATURDAY INTO EARLY SUNDAY. AN APPROACHING WINTER STORM COULD
BEGIN TO IMPACT THE AREA BY LATE SUNDAY AFTERNOON OR SUNDAY
EVENING...WITH ACCUMULATING SNOW POSSIBLE.
&&
.NEAR TERM /THROUGH TONIGHT/...
145 PM UPDATE... ONLY MINOR TWEAKS MADE TO THE GRIDS THIS PD.
AREA-WIDE WIND CHILL ADVSY STILL LOOKS ON TRACK FOR THE OVERNIGHT
HRS...AS VERY STG 925-850 MB CAA THROUGH THIS EVE...SHOULD SEND
AIR TEMPS INTO THE SINGLE DIGITS ABV OR BLO ZERO TNT...WITH THE
PRES GRADIENT REMAINING RELATIVELY TIGHT THIS EVE...AND ONLY
SLOWLY RELAXING LATE. MOST AREAS SHOULD SEE APPARENT TEMPS IN THE
-10 TO -20 RANGE...WITH LOCALLY COLDER VALUES IN OUR FAR NRN AND
ERN ZNS.
AS FAR AS THE LES ADVSY GOES...NO CHGS ATTM. ALTHOUGH BLYR INSTAB
(TERRESTRIAL CAPE VALUES OF 15-30 J/KG) TEMPORARILY RESULTED IN A
MORE CELLULAR APPEARANCE TO THE SNOW SHWRS EARLIER THIS AFTN
LOW-LVL STABILIZATION AND INCRG SHEAR SHOULD RESULT IN THE RE-
EMERGENCE OF WELL DEFINED BANDS BY 21Z OR SO. IN FACT...EVIDENCE
OF SUCH IS ALREADY SEEN ON KBGM RADAR IMAGERY ATTM. MOST HI-RES
MODEL GUIDANCE HINTS THAT MULTI-BANDS/FINGER LKS BANDS WILL REMAIN
AT PLAY TIL AT LEAST 06-12Z SAT. OVERALL...INTENSITY SHOULD WANE
AFTER 06Z...AS MODEL SNDGS SHOW THE CAPPING INVERSION LWRG TO AOB
875-900 MB. WE`LL STICK WITH OUR 3-6" TOTALS FOR NOW...ALTHOUGH
WUDN`T BE SURPRISED TO SEE LOCALLY HIER AMTS...SPCLY IN SERN
TOMPKINS AND/OR NRN TIOGA.
OUTSIDE OF MULTI-BAND AREAS...EITHER WIDELY SCTD -SHSN/FLRYS...OR
JUST DRY WX...IS FORESEEN.
PREV DISC... 10 AM UPDATE... WE`VE ISSUED A LES ADVSY FOR
TOMPKINS...TIOGA...BROOME...AND SUSQ CNTYS...AS CONFIDENCE HAS
BECOME FAIRLY HIGH IN THE MAINTENANCE OF A WELL DVLPD FINGER LKS
BAND...THROUGH AT LEAST 00-03Z THIS EVE. OUR FIRST STAB AT SNOW
TOTALS IS 3-6"...BUT LOCALLY HIER AMTS ARE CERTAINLY PSBL.
NO OTHER SIG CHGS ATTM.
EARLIER DISC... 830 AM UPDATE... SN/+SN IS BEING OBSERVED ATTM
WITHIN A SW-NE ORIENTED BAND ACRS NE PA AND PTNS OF THE WRN
CATSKILLS. THIS FEATURE IS ON THE NWRN/DEFORMATION SIDE OF A S/WV
LIFTING THROUGH THE RGN THIS MRNG. POP/WX/SNOWFALL GRIDS WERE
UPDATED TO REFLECT SUCH DVLPMTS. WE`VE ADDED A CORRIDOR OF 2-3"
ADDTNL SNOWFALL WITHIN THE AFOREMENTIONED BAND AREA THROUGH
15-16Z. A SHORT-TERM SPS WAS ALSO ISSUED.
OTHWS...THE FCST IS PRETTY WELL IN HAND. FAIRLY DEEP LYR OF INSTAB
NOTED ON THE 12Z KBUF SNDG...INDICATIVE OF THE AMS WE`LL HAVE
THROUGH EARLY AFTN...AHD OF THE NEXT INCOMING S/WV. LIKELY POPS
FOR SNOW SHWRS OVER MOST OF CNY...WITH MORE SCTD ACTIVITY ACRS
MUCH OF NE PA...STILL SEEMS REASONABLE...WITH A FLUFFY 1-2"
ANTICIPATED IN THE MOST PERSISTENT SHSN. IT`S WORTH NOTING THAT
THE LATEST HRRR AND HI-RES ARW OUTPUT IN PARTICULAR SHOW A WELL
FORMED MULTI-BAND/FINGER LKS BAND FROM LTR THIS MRNG...THROUGH THE
AFTN...AND INTO THE EVE HRS...DOWN THE AXIS OF CAYUGA LAKE...AND THEN
SEWD FROM THERE THROUGH AT LEAST TOMPKINS/TIOGA CNTYS. SINCE THERE
ARE ALREADY SOME INDICATIONS OF BANDING IN THIS GENERAL AREA
ATTM...WE`LL MONITOR THAT CLOSELY THROUGH THE DAY.
GIVEN STG CAA THROUGHOUT THE COLUMN...SHARPLY FALLING TEMPS STILL
LOOK LIKELY...AND OUR PREVIOUSLY ADVERTISED TREND WAS KEPT IN TACT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
2 PM FRI UPDATE... OVERALL...THINGS LOOK FAIRLY QUIET SAT-SUN
MRNG. WINDS SHOULD RELAX SAT...SO THE WIND CHILL EXPIRATION TIME
OF 16Z STILL LOOKS GOOD ATTM. A WEAK SFC FRNT AND NRN STREAM S/WV
ARE PROGGED TO TRAVERSE THE FA SAT NGT INTO THE FIRST PART OF
SUN...WITH ONLY SCTD LGT SNOW SHWRS AND FLRYS ANTICIPATED...AND
LTL IN THE WAY OF ACCUM.
RECENT GLOBAL MODEL TRENDS (GFS/EC/GEM) HAVE PERSISTED WITH THE
12Z FRI CYCLE...INDICATING A MORE AMPLIFIED UPR-LVL WV...FARTHER N
SFC LOW TRACK...AND RESULTANT INCREASED SNOWFALL POTENTIAL FOR
CNY/NE PA. MUCH MORE ON THIS SYSTEM IN THE FOLLOWING SXN. FOR
NOW...WE`VE BROUGHT THE LEADING EDGE OF STEADIER SNOW (CHC-LIKELY
POPS) INTO AT LEAST SWRN/SRN PTNS OF THE FA BY MID TO LATE AFTN ON SUN.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
CONFIDENCE IS GROWING THAT THE AREA WILL BE AFFECTED BY A MOISTURE LADEN STORM
SYSTEM AS IT MOVES FROM THE OHIO VALLEY OFF THE EAST COAST SUNDAY
NIGHT INTO MONDAY. EXPECT SNOW TO CONTINUE OVERSPREADING THE
REGION SUNDAY EVENING AND POTENTIALLY BECOME HEAVY AT TIMES
OVERNIGHT INTO EARLY MONDAY. AS THIS EVENT IS STILL MORE THAN 48
HOURS OUT, THERE IS STILL A LOT OF UNCERTAINTY IN THE DETAILS OF
THE SYSTEM AND IT`S EXACT TRACK BUT AS DISCUSSED ABOVE FORECAST
GUIDANCE HAS COME INTO BETTER AGREEMENT WITH THIS UPDATE CYCLE.
THE TRACK OF THE LOW SOUTH OF THE CWA SHOULD RESULT IN THE HEAVIER
AMOUNTS (POTENTIALLY 6+ INCHES) GENERALLY OCCURRING ACROSS NE PA
NORTHWARD ACROSS THE SOUTHERN TIER OF UPSTATE NEW YORK THEN EAST
INTO THE CATSKILLS WITH LIGHTER AMOUNTS FARTHER NORTH. WORTH
NOTING, HOWEVER, IS THAT IF THE LOW TRACK WERE TO TREND EVEN
FARTHER NORTH THIS COULD INTRODUCE MIXED PRECIP INTO NE PA CUTTING
AMOUNTS DOWN THERE AND RESULTING IN MORE WIDESPREAD HIGHER TOTALS
OVER NY. SO, AS MENTIONED, STILL UNCERTAINTY SO WE WILL HOLD OFF
ON WATCH AT THIS TIME. FINALLY, THE ARCTIC AIR IN PLACE AHEAD OF
THIS SYSTEM WILL ALSO RESULT IN THIS BEING A VERY COLD EVENT WITH
TEMPS GENERALLY IN THE TEENS AND EVEN SINGLE DIGITS IN THE FAR NORTH WHICH
WILL BE ACCOMPANIED BY INCREASING WINDS LATER MONDAY.
EXPECT SNOW TO WIND DOWN BY LATER MONDAY WITH SOME LAKE EFFECT
POSSIBLE IN IT`S WAKE MONDAY NIGHT. ALSO EXPECT VERY COLD TEMPS BY
LATER MONDAY NIGHT AS ARCTIC HIGH BUILDS IN WITH WIDESPREAD
SUBZERO READINGS. TUESDAY WILL BE GENERALLY FAIR BUT COLD WITH
BRIEF MODERATION TO SEASONAL WEDNESDAY BEFORE ANOTHER ARCTIC FRONT MOVES
THROUGH LATE WEDNESDAY WITH SNOW SHOWERS AND COLDER TEMPS TO
FOLLOW FOR THE END OF THE WEEK. NW FLOW ALSO WILL BRING THE
POTENTIAL FOR SOME LAKE EFFECT INTO THURSDAY.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
SNOW SHOWERS, HEAVY AT TIMES, WILL CONTINUE TO PRODUCE RESTRICTIONS THIS
AFTERNOON. GENERALLY EXPECT IFR VISBYS FOR KITH/KBGM/KSYR AND AT
TIMES KELM. EXPECT VISIBILITIES IN HEAVIER SNOW SHOWERS TO BE
REDUCED TO A 1/2 SM AT TIMES. KRME/KAVP WILL GENERALLY SEE MVFR
CONDITIONS THIS AFTERNOON AS THEY SHOULD MISS THE HEAVIEST OF THESE
SHOWERS.
THE GENERAL TREND WILL BE FOR IMPROVING CONDITIONS LATER THIS
EVENING INTO THE OVERNIGHT WITH MOST SITES BECOMING VFR BY
MORNING. KITH/KBGM WILL TAKE THE LONGEST TO IMPROVE DUE TO THE
LAKE EFFECT OFF THE FINGER LAKES. EXPECT IFR VISBYS TO LAST
THROUGH THIS EVENING FOR KITH WITH MVFR CONDITIONS PERSISTING
THERE BEYOND THIS TIME THROUGH THE REMAINDER OF THE TAF PERIOD.
NORTHWEST WINDS WILL PERSIST TODAY AT 10-15 KNOTS WITH GUSTS AROUND 25
KNOTS SLOWLY DECREASING OVERNIGHT.
OUTLOOK...
SAT NGT AND MOST OF SUN...VFR.
SUN NGT / MON... RESTRICTIONS LIKELY (MVFR/IFR) IN SNOW.
TUE...VFR.
WED...POSSIBLE RESTRICTIONS DUE TO SNOW SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR PAZ038>040-043-044-047-048-072.
LAKE EFFECT SNOW ADVISORY UNTIL 1 AM EST SATURDAY FOR PAZ039.
NY...WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ009-015>018-022>025-036-037-044>046-
055>057-062.
LAKE EFFECT SNOW ADVISORY UNTIL 1 AM EST SATURDAY FOR NYZ025-
055-056.
&&
$$
SYNOPSIS...MLJ
NEAR TERM...MLJ
SHORT TERM...MLJ
LONG TERM...PCF
AVIATION...PCF/RRM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
157 PM EST FRI JAN 30 2015
.SYNOPSIS...
VERY COLD AIR WILL CONTINUE TO POUR INTO THE REGION TONIGHT...WITH
LAKE-EFFECT SNOW PERSISTING DOWNWIND FROM THE FINGER LAKES...AND
BITTERLY COLD WIND CHILLS AREA-WIDE. COLD TEMPERATURES WILL LAST
THROUGH THE UPCOMING WEEKEND...WITH ONLY A FEW FLURRIES FORESEEN
FROM SATURDAY INTO EARLY SUNDAY. AN APPROACHING WINTER STORM COULD
BEGIN TO IMPACT THE AREA BY LATE SUNDAY AFTERNOON OR SUNDAY
EVENING...WITH ACCUMULATING SNOW POSSIBLE.
&&
.NEAR TERM /THROUGH TONIGHT/...
145 PM UPDATE... ONLY MINOR TWEAKS MADE TO THE GRIDS THIS PD.
AREA-WIDE WIND CHILL ADVSY STILL LOOKS ON TRACK FOR THE OVERNIGHT
HRS...AS VERY STG 925-850 MB CAA THROUGH THIS EVE...SHOULD SEND
AIR TEMPS INTO THE SINGLE DIGITS ABV OR BLO ZERO TNT...WITH THE
PRES GRADIENT REMAINING RELATIVELY TIGHT THIS EVE...AND ONLY
SLOWLY RELAXING LATE. MOST AREAS SHOULD SEE APPARENT TEMPS IN THE
-10 TO -20 RANGE...WITH LOCALLY COLDER VALUES IN OUR FAR NRN AND
ERN ZNS.
AS FAR AS THE LES ADVSY GOES...NO CHGS ATTM. ALTHOUGH BLYR INSTAB
(TERRESTRIAL CAPE VALUES OF 15-30 J/KG) TEMPORARILY RESULTED IN A
MORE CELLULAR APPEARANCE TO THE SNOW SHWRS EARLIER THIS AFTN
...LOW-LVL STABILIZATION AND INCRG SHEAR SHOULD RESULT IN THE RE-
EMERGENCE OF WELL DEFINED BANDS BY 21Z OR SO. IN FACT...EVIDENCE
OF SUCH IS ALREADY SEEN ON KBGM RADAR IMAGERY ATTM. MOST HI-RES
MODEL GUIDANCE HINTS THAT MULTI-BANDS/FINGER LKS BANDS WILL REMAIN
AT PLAY TIL AT LEAST 06-12Z SAT. OVERALL...INTENSITY SHOULD WANE
AFTER 06Z...AS MODEL SNDGS SHOW THE CAPPING INVERSION LWRG TO AOB
875-900 MB. WE`LL STICK WITH OUR 3-6" TOTALS FOR NOW...ALTHOUGH
WUDN`T BE SURPRISED TO SEE LOCALLY HIER AMTS...SPCLY IN SERN
TOMPKINS AND/OR NRN TIOGA.
OUTSIDE OF MULTI-BAND AREAS...EITHER WIDELY SCTD -SHSN/FLRYS...OR
JUST DRY WX...IS FORESEEN.
PREV DISC... 10 AM UPDATE... WE`VE ISSUED A LES ADVSY FOR
TOMPKINS...TIOGA...BROOME...AND SUSQ CNTYS...AS CONFIDENCE HAS
BECOME FAIRLY HIGH IN THE MAINTENANCE OF A WELL DVLPD FINGER LKS
BAND...THROUGH AT LEAST 00-03Z THIS EVE. OUR FIRST STAB AT SNOW
TOTALS IS 3-6"...BUT LOCALLY HIER AMTS ARE CERTAINLY PSBL.
NO OTHER SIG CHGS ATTM.
EARLIER DISC... 830 AM UPDATE... SN/+SN IS BEING OBSERVED ATTM
WITHIN A SW-NE ORIENTED BAND ACRS NE PA AND PTNS OF THE WRN
CATSKILLS. THIS FEATURE IS ON THE NWRN/DEFORMATION SIDE OF A S/WV
LIFTING THROUGH THE RGN THIS MRNG. POP/WX/SNOWFALL GRIDS WERE
UPDATED TO REFLECT SUCH DVLPMTS. WE`VE ADDED A CORRIDOR OF 2-3"
ADDTNL SNOWFALL WITHIN THE AFOREMENTIONED BAND AREA THROUGH
15-16Z. A SHORT-TERM SPS WAS ALSO ISSUED.
OTHWS...THE FCST IS PRETTY WELL IN HAND. FAIRLY DEEP LYR OF INSTAB
NOTED ON THE 12Z KBUF SNDG...INDICATIVE OF THE AMS WE`LL HAVE
THROUGH EARLY AFTN...AHD OF THE NEXT INCOMING S/WV. LIKELY POPS
FOR SNOW SHWRS OVER MOST OF CNY...WITH MORE SCTD ACTIVITY ACRS
MUCH OF NE PA...STILL SEEMS REASONABLE...WITH A FLUFFY 1-2"
ANTICIPATED IN THE MOST PERSISTENT SHSN. IT`S WORTH NOTING THAT
THE LATEST HRRR AND HI-RES ARW OUTPUT IN PARTICULAR SHOW A WELL
FORMED MULTI-BAND/FINGER LKS BAND FROM LTR THIS MRNG...THROUGH THE
AFTN...AND INTO THE EVE HRS...DOWN THE AXIS OF CAYUGA LAKE...AND THEN
SEWD FROM THERE THROUGH AT LEAST TOMPKINS/TIOGA CNTYS. SINCE THERE
ARE ALREADY SOME INDICATIONS OF BANDING IN THIS GENERAL AREA
ATTM...WE`LL MONITOR THAT CLOSELY THROUGH THE DAY.
GIVEN STG CAA THROUGHOUT THE COLUMN...SHARPLY FALLING TEMPS STILL
LOOK LIKELY...AND OUR PREVIOUSLY ADVERTISED TREND WAS KEPT IN TACT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
2 PM FRI UPDATE... OVERALL...THINGS LOOK FAIRLY QUIET SAT-SUN
MRNG. WINDS SHOULD RELAX SAT...SO THE WIND CHILL EXPIRATION TIME
OF 16Z STILL LOOKS GOOD ATTM. A WEAK SFC FRNT AND NRN STREAM S/WV
ARE PROGGED TO TRAVERSE THE FA SAT NGT INTO THE FIRST PART OF
SUN...WITH ONLY SCTD LGT SNOW SHWRS AND FLRYS ANTICIPATED...AND
LTL IN THE WAY OF ACCUM.
RECENT GLOBAL MODEL TRENDS (GFS/EC/GEM) HAVE PERSISTED WITH THE
12Z FRI CYCLE...INDICATING A MORE AMPLIFIED UPR-LVL WV...FARTHER N
SFC LOW TRACK...AND RESULTANT INCREASED SNOWFALL POTENTIAL FOR
CNY/NE PA. MUCH MORE ON THIS SYSTEM IN THE FOLLOWING SXN. FOR
NOW...WE`VE BROUGHT THE LEADING EDGE OF STEADIER SNOW (CHC-LIKELY
POPS) INTO AT LEAST SWRN/SRN PTNS OF THE FA BY MID TO LATE AFTN ON SUN.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
300 AM UPDATE...CURRENT FORECAST IN GOOD SHAPE JUST MINOR
ADJUSTMENTS BASED ON LATEST WPC GUIDANCE. THE GFS/ECMWF ARE STILL
IN FAIR AGREEMENT WITH THE 00Z CYCLE AND SHOW THE SFC LOW MONDAY
MORNING MOVING THROUGH NRN VA. THE CANADIAN CONTINUES TO BE
FARTHER SOUTH AS IT TRACKS THE LOW THROUGH NORTH CAROLINA. BASED
ON FAIR AGREEMENT WITH THE GFS/ECMWF FOR TWO MODEL RUNS UPPED THE
POPS TO LIKELY ACROSS THE FAR SE FA.
330 PM UPDATE... MODEL DISAGREEMENT/INCONSISTENCY CONTS WITH THE
LATEST CYCLES REGARDING THE SUN NGT-MON STORM SYSTEM. THE MOST RECENT
RUNS OF THE EC/GFS HAVE TRENDED NWD SOMEWHAT AGN...NOW TRACKING
THE SFC LOW THROUGH VA AND SERN MD...AND BRINGING LGT SNOW AT
LEAST TO THE PA/NY BORDER...IF NOT INTO NY`S SRN TIER.
MEANWHILE...THE CAN GEM HAS NOW GONE MUCH FARTHER S...TAKING THE
SFC WV THROUGH THE CAROLINAS...WITH LTL OR NO SNOWFALL FOR OUR FA.
GIVEN ALL THE UNCERTAINTY...THE EXPECTATION OF FURTHER MODEL
WAFFLING...AND ALSO THE FACT THAT THE SUPPORTING S/WV ENERGY IS
NOW JUST APPROACHING THE PACIFIC COAST OF NORTH AMERICA...WE`LL
SIMPLY MAKE VERY SMALL INCREMENTAL CHGS ATTM...JUST EASING POPS
UPWARD AGN TO INCORPORATE THE LATEST EC/GFS TRENDS. THIS RESULTS
IN LIKELY POPS FOR OUR FAR SRN ZNS SUN NGT (BACK DOWN TO CHC BY
MON)...AND CHC POPS THROUGHOUT THIS PD FOR OUR NY SRN TIER CNTYS.
ALTHOUGH...STRICTLY SPEAKING...WE`RE CURRENTLY INDICATING THE
POTENTIAL FOR A FEW INCHES OF SNOW OVER PTNS OF NE PA...THIS WILL
CERTAINLY BE SUBJECT TO CHANGE OVER THE NEXT COUPLE OF DAYS. STAY
TUNED FOR THE LATEST UPDATES ON THIS SITN.
TUE INTO WED LOOK QUIETER...BUT VERY COLD...WITH ONLY SOME FLRYS
FORESEEN AT WORST.
BY WED NGT AND THU...OUR NEXT REINFORCING COLD FRNT AND NRN STREAM
S/WV APPROACH...BRINGING A CHC OF SNOW SHWRS. THE EC IS ALSO
SHOWING THE PSBLTY THAT SOME SRN STREAM MOISTURE GETS INCORPORATED
INTO THE SYSTEM. STILL PLENTY OF TIME TO SORT ALL OF THESE FINE
DETAILS OUT.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
SNOW SHOWERS, HEAVY AT TIMES, WILL CONTINUE TO PRODUCE RESTRICTIONS THIS
AFTERNOON. GENERALLY EXPECT IFR VISBYS FOR KITH/KBGM/KSYR AND AT
TIMES KELM. EXPECT VISIBILITIES IN HEAVIER SNOW SHOWERS TO BE
REDUCED TO A 1/2 SM AT TIMES. KRME/KAVP WILL GENERALLY SEE MVFR
CONDITIONS THIS AFTERNOON AS THEY SHOULD MISS THE HEAVIEST OF THESE
SHOWERS.
THE GENERAL TREND WILL BE FOR IMPROVING CONDITIONS LATER THIS
EVENING INTO THE OVERNIGHT WITH MOST SITES BECOMING VFR BY
MORNING. KITH/KBGM WILL TAKE THE LONGEST TO IMPROVE DUE TO THE
LAKE EFFECT OFF THE FINGER LAKES. EXPECT IFR VISBYS TO LAST
THROUGH THIS EVENING FOR KITH WITH MVFR CONDITIONS PERSISTING
THERE BEYOND THIS TIME THROUGH THE REMAINDER OF THE TAF PERIOD.
NORTHWEST WINDS WILL PERSIST TODAY AT 10-15 KNOTS WITH GUSTS AROUND 25
KNOTS SLOWLY DECREASING OVERNIGHT.
OUTLOOK...
SAT NGT AND MOST OF SUN...VFR.
SUN NGT MON...PSBL RESTRICTIONS (MVFR/IFR) IN SNOW.
TUE...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR PAZ038>040-043-044-047-048-072.
LAKE EFFECT SNOW ADVISORY UNTIL 1 AM EST SATURDAY FOR PAZ039.
NY...WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ009-015>018-022>025-036-037-044>046-
055>057-062.
LAKE EFFECT SNOW ADVISORY UNTIL 1 AM EST SATURDAY FOR NYZ025-
055-056.
&&
$$
SYNOPSIS...MLJ
NEAR TERM...MLJ
SHORT TERM...MLJ
LONG TERM...MLJ/RRM
AVIATION...PCF/RRM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1259 PM EST FRI JAN 30 2015
.SYNOPSIS...
A COLD FRONT IS MOVING THROUGH THE REGION THIS MORNING. LIGHT
ACCUMULATING LAKE EFFECT SNOW WILL OCCUR TODAY. TEMPERATURES WILL
PLUMMET TODAY...WITH GUSTY WINDS SENDING WIND CHILLS WELL BELOW
ZERO TONIGHT. COLD AIR WILL REMAIN WELL INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE... WE`VE ISSUED A LES ADVSY FOR
TOMPKINS...TIOGA...BROOME...AND SUSQ CNTYS...AS CONFIDENCE HAS
BECOME FAIRLY HIGH IN THE MAINTENANCE OF A WELL DVLPD FINGER LKS
BAND...THROUGH AT LEAST 00-03Z THIS EVE. OUR FIRST STAB AT SNOW
TOTALS IS 3-6"...BUT LOCALLY HIER AMTS ARE CERTAINLY PSBL.
NO OTHER SIG CHGS ATTM.
830 AM UPDATE... SN/+SN IS BEING OBSERVED ATTM WITHIN A SW-NE
ORIENTED BAND ACRS NE PA AND PTNS OF THE WRN CATSKILLS. THIS
FEATURE IS ON THE NWRN/DEFORMATION SIDE OF A S/WV LIFTING THROUGH
THE RGN THIS MRNG. POP/WX/SNOWFALL GRIDS WERE UPDATED TO REFLECT
SUCH DVLPMTS. WE`VE ADDED A CORRIDOR OF 2-3" ADDTNL SNOWFALL
WITHIN THE AFOREMENTIONED BAND AREA THROUGH 15-16Z. A SHORT-TERM
SPS WAS ALSO ISSUED.
OTHWS...THE FCST IS PRETTY WELL IN HAND. FAIRLY DEEP LYR OF INSTAB
NOTED ON THE 12Z KBUF SNDG...INDICATIVE OF THE AMS WE`LL HAVE
THROUGH EARLY AFTN...AHD OF THE NEXT INCOMING S/WV. LIKELY POPS
FOR SNOW SHWRS OVER MOST OF CNY...WITH MORE SCTD ACTIVITY ACRS
MUCH OF NE PA...STILL SEEMS REASONABLE...WITH A FLUFFY 1-2"
ANTICIPATED IN THE MOST PERSISTENT SHSN. IT`S WORTH NOTING THAT
THE LATEST HRRR AND HI-RES ARW OUTPUT IN PARTICULAR SHOW A WELL
FORMED MULTI-BAND/FINGER LKS BAND FROM LTR THIS MRNG...THROUGH THE
AFTN...AND INTO THE EVE HRS...DOWN THE AXIS OF CAYUGA LAKE...AND THEN
SEWD FROM THERE THROUGH AT LEAST TOMPKINS/TIOGA CNTYS. SINCE THERE
ARE ALREADY SOME INDICATIONS OF BANDING IN THIS GENERAL AREA
ATTM...WE`LL MONITOR THAT CLOSELY THROUGH THE DAY.
GIVEN STG CAA THROUGHOUT THE COLUMN...SHARPLY FALLING TEMPS STILL
LOOK LIKELY...AND OUR PREVIOUSLY ADVERTISED TREND WAS KEPT IN TACT.
PREV DISC... 3 AM UPDATE...
FRONTS MOVING THROUGH THE CWA THIS MORNING SHIFTING THE WINDS TO
WEST THEN NW. MOST OF ACCUMULATING SNOW WITH FRONTS OVER
WITH...HAVING MOVED INTO ERN NY EARLY THIS MORNING. GIVEN THE
DURATION AND THE OBS FROM SYR AND BGM PROBABLY GOT LESS THAN 4
INCHES. LAKE EFFECT WILL START WITH THE SECOND COLD FRONT. THIS
BACKED UP ALOFT WITH A SHORT WAVE AND TROF. LOW LEVEL WIND FLOW
SHIFTS FROM 280 TO 310. ALSO WINDS INCREASE TO 10 TO 20 MPH
BRINGING IN MUCH COLDER AIR. LAKE EFFECT STARTS WITH MULTIBANDS.
THIS WILL SET UP IN THE USUAL AREAS OF THE EASTERN FINGER LAKES
AND NORTHERN SUSQUEHANNA REGION. SNOW AMOUNTS WILL BE MOSTLY 1 TO
3 INCHES. THE WIND WILL CAUSE DRIFTING. SNOW AMOUNTS BELOW
ADVISORY CRITERIA SO DROPPED WWA.
TEMPERATURES TO FALL SLOWLY ALL DAY. WIND CHILLS APPROACH ZERO
THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
3 AM UPDATE...
WIND CHILL ADVISORY ISSUED FOR ENTIRE CWA. WIND CHILL TEMPS WELL
BELOW ZERO WITH TEMPERATURE FALLING INTO THE SINGLE DIGITS ABOVE
AND BELOW ZERO. WINDS ONLY SLOWLY DIMINISH TONIGHT FROM WEST TO
EAST. WINDS STAY ABOVE 10 MPH.
LAKE EFFECT SNOW WILL DIMINISH AS DRY AIR COMES IN ALOFT AND THE
DENDRITE ZONE FALLS TO THE SFC. WEAK MULTIBANDS WILL CONTINUE
MOSTLY IN THE FINGER LAKES WITH LITTLE ACCUMULATION. LOCALIZED
AMOUNTS UP TO 2 INCHES. THE LAKE EFFECT DIES SATURDAY WHEN THE LL
WINDS SHIFT.
SAT NGT A WEAK FRONT PASSES THROUGH WITH LIGHT SNOW FOR CENT NY.
FORCING AND MOISTURE LACKING IN THE NORTHERN STREAM.
MODELS HAVE TRENDED NORTH AGAIN WITH THE SUNDAY TO MONDAY STORM.
NOW NE PA COULD GET SEVERAL INCHES WITH LESSER AMOUNTS IN NY. SNOW
STARTS SUN AFTN AND CONTINUES INTO MONDAY. THE STORM TRACK IS NOW
THROUGH THE MID ATLANTIC STATES THEN SLOWING OFF THE NEW ENGLAND
COAST AS IT INTENSIFIES. STILL MUCH UNCERTAINTY...BUT UPPED POPS,
QPF, AND SNOWFALL. CONTINUE TO MENTION IN THE HWO.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
300 AM UPDATE...CURRENT FORECAST IN GOOD SHAPE JUST MINOR
ADJUSTMENTS BASED ON LATEST WPC GUIDANCE. THE GFS/ECMWF ARE STILL
IN FAIR AGREEMENT WITH THE 00Z CYCLE AND SHOW THE SFC LOW MONDAY
MORNING MOVING THROUGH NRN VA. THE CANADIAN CONTINUES TO BE
FARTHER SOUTH AS IT TRACKS THE LOW THROUGH NORTH CAROLINA. BASED
ON FAIR AGREEMENT WITH THE GFS/ECMWF FOR TWO MODEL RUNS UPPED THE
POPS TO LIKELY ACROSS THE FAR SE FA.
330 PM UPDATE... MODEL DISAGREEMENT/INCONSISTENCY CONTS WITH THE
LATEST CYCLES REGARDING THE SUN NGT-MON STORM SYSTEM. THE MOST RECENT
RUNS OF THE EC/GFS HAVE TRENDED NWD SOMEWHAT AGN...NOW TRACKING
THE SFC LOW THROUGH VA AND SERN MD...AND BRINGING LGT SNOW AT
LEAST TO THE PA/NY BORDER...IF NOT INTO NY`S SRN TIER.
MEANWHILE...THE CAN GEM HAS NOW GONE MUCH FARTHER S...TAKING THE
SFC WV THROUGH THE CAROLINAS...WITH LTL OR NO SNOWFALL FOR OUR FA.
GIVEN ALL THE UNCERTAINTY...THE EXPECTATION OF FURTHER MODEL
WAFFLING...AND ALSO THE FACT THAT THE SUPPORTING S/WV ENERGY IS
NOW JUST APPROACHING THE PACIFIC COAST OF NORTH AMERICA...WE`LL
SIMPLY MAKE VERY SMALL INCREMENTAL CHGS ATTM...JUST EASING POPS
UPWARD AGN TO INCORPORATE THE LATEST EC/GFS TRENDS. THIS RESULTS
IN LIKELY POPS FOR OUR FAR SRN ZNS SUN NGT (BACK DOWN TO CHC BY
MON)...AND CHC POPS THROUGHOUT THIS PD FOR OUR NY SRN TIER CNTYS.
ALTHOUGH...STRICTLY SPEAKING...WE`RE CURRENTLY INDICATING THE
POTENTIAL FOR A FEW INCHES OF SNOW OVER PTNS OF NE PA...THIS WILL
CERTAINLY BE SUBJECT TO CHANGE OVER THE NEXT COUPLE OF DAYS. STAY
TUNED FOR THE LATEST UPDATES ON THIS SITN.
TUE INTO WED LOOK QUIETER...BUT VERY COLD...WITH ONLY SOME FLRYS
FORESEEN AT WORST.
BY WED NGT AND THU...OUR NEXT REINFORCING COLD FRNT AND NRN STREAM
S/WV APPROACH...BRINGING A CHC OF SNOW SHWRS. THE EC IS ALSO
SHOWING THE PSBLTY THAT SOME SRN STREAM MOISTURE GETS INCORPORATED
INTO THE SYSTEM. STILL PLENTY OF TIME TO SORT ALL OF THESE FINE
DETAILS OUT.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SNOW SHOWERS, HEAVY AT TIMES, WILL CONTINUE TO PRODUCE RESTRICTIONS THIS
AFTERNOON. GENERALLY EXPECT IFR VISBYS FOR KITH/KBGM/KSYR AND AT
TIMES KELM. EXPECT VISIBILITIES IN HEAVIER SNOW SHOWERS TO BE
REDUCED TO A 1/2 SM AT TIMES. KRME/KAVP WILL GENERALLY SEE MVFR
CONDITIONS THIS AFTERNOON AS THEY SHOULD MISS THE HEAVIST OF THESE
SHOWERS.
THE GENERAL TREND WILL BE FOR IMPROVING CONDITINOS LATER THIS
EVENING INTO THE OVERNIGHT WITH MOST SITES BECOMING VFR BY
MORNING. KITH/KBGM WILL TAKE THE LONGEST TO IMPROVE DUE TO THE
LAKE EFFECT OFF THE FINGER LAKES. EXPECT IFR VISBYS TO LAST
THROUGH THIS EVENING FOR KITH WITH MVFR CONDITIONS PERSISTING
THERE BEYOND THIS TIME THROUGH THE REMAINDER OF THE TAF PERIOD.
NORTHWEST WINDS WILL PERSIST TODAY AT 10-15 KNOTS WITH GUSTS AROUND 25
KNOTS SLOWLY DECREASING OVERNIGHT.
OUTLOOK...
SAT NGT AND MOST OF SUN...VFR.
SUN NGT MON...PSBL RESTRICTIONS (MVFR/IFR) IN SNOW.
TUE...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR PAZ038>040-043-044-047-048-072.
LAKE EFFECT SNOW ADVISORY UNTIL 1 AM EST SATURDAY FOR PAZ039.
NY...WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ009-015>018-022>025-036-037-044>046-
055>057-062.
LAKE EFFECT SNOW ADVISORY UNTIL 1 AM EST SATURDAY FOR NYZ025-
055-056.
&&
$$
SYNOPSIS...TAC
NEAR TERM...MLJ/TAC
SHORT TERM...TAC
LONG TERM...MLJ/RRM
AVIATION...PCF/RRM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1000 AM EST FRI JAN 30 2015
.SYNOPSIS...
A COLD FRONT IS MOVING THROUGH THE REGION THIS MORNING. LIGHT
ACCUMULATING LAKE EFFECT SNOW WILL OCCUR TODAY. TEMPERATURES WILL
PLUMMET TODAY...WITH GUSTY WINDS SENDING WIND CHILLS WELL BELOW
ZERO TONIGHT. COLD AIR WILL REMAIN WELL INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE... WE`VE ISSUED A LES ADVSY FOR
TOMPKINS...TIOGA...BROOME...AND SUSQ CNTYS...AS CONFIDENCE HAS
BECOME FAIRLY HIGH IN THE MAINTENANCE OF A WELL DVLPD FINGER LKS
BAND...THROUGH AT LEAST 00-03Z THIS EVE. OUR FIRST STAB AT SNOW
TOTALS IS 3-6"...BUT LOCALLY HIER AMTS ARE CERTAINLY PSBL.
NO OTHER SIG CHGS ATTM.
830 AM UPDATE... SN/+SN IS BEING OBSERVED ATTM WITHIN A SW-NE
ORIENTED BAND ACRS NE PA AND PTNS OF THE WRN CATSKILLS. THIS
FEATURE IS ON THE NWRN/DEFORMATION SIDE OF A S/WV LIFTING THROUGH
THE RGN THIS MRNG. POP/WX/SNOWFALL GRIDS WERE UPDATED TO REFLECT
SUCH DVLPMTS. WE`VE ADDED A CORRIDOR OF 2-3" ADDTNL SNOWFALL
WITHIN THE AFOREMENTIONED BAND AREA THROUGH 15-16Z. A SHORT-TERM
SPS WAS ALSO ISSUED.
OTHWS...THE FCST IS PRETTY WELL IN HAND. FAIRLY DEEP LYR OF INSTAB
NOTED ON THE 12Z KBUF SNDG...INDICATIVE OF THE AMS WE`LL HAVE
THROUGH EARLY AFTN...AHD OF THE NEXT INCOMING S/WV. LIKELY POPS
FOR SNOW SHWRS OVER MOST OF CNY...WITH MORE SCTD ACTIVITY ACRS
MUCH OF NE PA...STILL SEEMS REASONABLE...WITH A FLUFFY 1-2"
ANTICIPATED IN THE MOST PERSISTENT SHSN. IT`S WORTH NOTING THAT
THE LATEST HRRR AND HI-RES ARW OUTPUT IN PARTICULAR SHOW A WELL
FORMED MULTI-BAND/FINGER LKS BAND FROM LTR THIS MRNG...THROUGH THE
AFTN...AND INTO THE EVE HRS...DOWN THE AXIS OF CAYUGA LAKE...AND THEN
SEWD FROM THERE THROUGH AT LEAST TOMPKINS/TIOGA CNTYS. SINCE THERE
ARE ALREADY SOME INDICATIONS OF BANDING IN THIS GENERAL AREA
ATTM...WE`LL MONITOR THAT CLOSELY THROUGH THE DAY.
GIVEN STG CAA THROUGHOUT THE COLUMN...SHARPLY FALLING TEMPS STILL
LOOK LIKELY...AND OUR PREVIOUSLY ADVERTISED TREND WAS KEPT IN TACT.
PREV DISC... 3 AM UPDATE...
FRONTS MOVING THROUGH THE CWA THIS MORNING SHIFTING THE WINDS TO
WEST THEN NW. MOST OF ACCUMULATING SNOW WITH FRONTS OVER
WITH...HAVING MOVED INTO ERN NY EARLY THIS MORNING. GIVEN THE
DURATION AND THE OBS FROM SYR AND BGM PROBABLY GOT LESS THAN 4
INCHES. LAKE EFFECT WILL START WITH THE SECOND COLD FRONT. THIS
BACKED UP ALOFT WITH A SHORT WAVE AND TROF. LOW LEVEL WIND FLOW
SHIFTS FROM 280 TO 310. ALSO WINDS INCREASE TO 10 TO 20 MPH
BRINGING IN MUCH COLDER AIR. LAKE EFFECT STARTS WITH MULTIBANDS.
THIS WILL SET UP IN THE USUAL AREAS OF THE EASTERN FINGER LAKES
AND NORTHERN SUSQUEHANNA REGION. SNOW AMOUNTS WILL BE MOSTLY 1 TO
3 INCHES. THE WIND WILL CAUSE DRIFTING. SNOW AMOUNTS BELOW
ADVISORY CRITERIA SO DROPPED WWA.
TEMPERATURES TO FALL SLOWLY ALL DAY. WIND CHILLS APPROACH ZERO
THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
3 AM UPDATE...
WIND CHILL ADVISORY ISSUED FOR ENTIRE CWA. WIND CHILL TEMPS WELL
BELOW ZERO WITH TEMPERATURE FALLING INTO THE SINGLE DIGITS ABOVE
AND BELOW ZERO. WINDS ONLY SLOWLY DIMINISH TONIGHT FROM WEST TO
EAST. WINDS STAY ABOVE 10 MPH.
LAKE EFFECT SNOW WILL DIMINISH AS DRY AIR COMES IN ALOFT AND THE
DENDRITE ZONE FALLS TO THE SFC. WEAK MULTIBANDS WILL CONTINUE
MOSTLY IN THE FINGER LAKES WITH LITTLE ACCUMULATION. LOCALIZED
AMOUNTS UP TO 2 INCHES. THE LAKE EFFECT DIES SATURDAY WHEN THE LL
WINDS SHIFT.
SAT NGT A WEAK FRONT PASSES THROUGH WITH LIGHT SNOW FOR CENT NY.
FORCING AND MOISTURE LACKING IN THE NORTHERN STREAM.
MODELS HAVE TRENDED NORTH AGAIN WITH THE SUNDAY TO MONDAY STORM.
NOW NE PA COULD GET SEVERAL INCHES WITH LESSER AMOUNTS IN NY. SNOW
STARTS SUN AFTN AND CONTINUES INTO MONDAY. THE STORM TRACK IS NOW
THROUGH THE MID ATLANTIC STATES THEN SLOWING OFF THE NEW ENGLAND
COAST AS IT INTENSIFIES. STILL MUCH UNCERTAINTY...BUT UPPED POPS,
QPF, AND SNOWFALL. CONTINUE TO MENTION IN THE HWO.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
300 AM UPDATE...CURRENT FORECAST IN GOOD SHAPE JUST MINOR
ADJUSTMENTS BASED ON LATEST WPC GUIDANCE. THE GFS/ECMWF ARE STILL
IN FAIR AGREEMENT WITH THE 00Z CYCLE AND SHOW THE SFC LOW MONDAY
MORNING MOVING THROUGH NRN VA. THE CANADIAN CONTINUES TO BE
FARTHER SOUTH AS IT TRACKS THE LOW THROUGH NORTH CAROLINA. BASED
ON FAIR AGREEMENT WITH THE GFS/ECMWF FOR TWO MODEL RUNS UPPED THE
POPS TO LIKELY ACROSS THE FAR SE FA.
330 PM UPDATE... MODEL DISAGREEMENT/INCONSISTENCY CONTS WITH THE
LATEST CYCLES REGARDING THE SUN NGT-MON STORM SYSTEM. THE MOST RECENT
RUNS OF THE EC/GFS HAVE TRENDED NWD SOMEWHAT AGN...NOW TRACKING
THE SFC LOW THROUGH VA AND SERN MD...AND BRINGING LGT SNOW AT
LEAST TO THE PA/NY BORDER...IF NOT INTO NY`S SRN TIER.
MEANWHILE...THE CAN GEM HAS NOW GONE MUCH FARTHER S...TAKING THE
SFC WV THROUGH THE CAROLINAS...WITH LTL OR NO SNOWFALL FOR OUR FA.
GIVEN ALL THE UNCERTAINTY...THE EXPECTATION OF FURTHER MODEL
WAFFLING...AND ALSO THE FACT THAT THE SUPPORTING S/WV ENERGY IS
NOW JUST APPROACHING THE PACIFIC COAST OF NORTH AMERICA...WE`LL
SIMPLY MAKE VERY SMALL INCREMENTAL CHGS ATTM...JUST EASING POPS
UPWARD AGN TO INCORPORATE THE LATEST EC/GFS TRENDS. THIS RESULTS
IN LIKELY POPS FOR OUR FAR SRN ZNS SUN NGT (BACK DOWN TO CHC BY
MON)...AND CHC POPS THROUGHOUT THIS PD FOR OUR NY SRN TIER CNTYS.
ALTHOUGH...STRICTLY SPEAKING...WE`RE CURRENTLY INDICATING THE
POTENTIAL FOR A FEW INCHES OF SNOW OVER PTNS OF NE PA...THIS WILL
CERTAINLY BE SUBJECT TO CHANGE OVER THE NEXT COUPLE OF DAYS. STAY
TUNED FOR THE LATEST UPDATES ON THIS SITN.
TUE INTO WED LOOK QUIETER...BUT VERY COLD...WITH ONLY SOME FLRYS
FORESEEN AT WORST.
BY WED NGT AND THU...OUR NEXT REINFORCING COLD FRNT AND NRN STREAM
S/WV APPROACH...BRINGING A CHC OF SNOW SHWRS. THE EC IS ALSO
SHOWING THE PSBLTY THAT SOME SRN STREAM MOISTURE GETS INCORPORATED
INTO THE SYSTEM. STILL PLENTY OF TIME TO SORT ALL OF THESE FINE
DETAILS OUT.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
A STRONG COLD FRONT HAS SWEPT THROUGH ALL THE TERMINALS THIS
MORNING. NORTHWEST FLOW COMBINED WITH MOISTURE TRAPPED UNDER AN
INVERSION WILL BRING WIDESPREAD MVFR/LOW MVFR CIGS TO THE AREA
THROUGH EARLY THIS EVENING ALONG WITH OCCASIONAL SNOW SHOWERS AND
FLURRIES. AT KITH/KBGM, OCCASIONAL IFR CIGS WILL OCCUR THROUGH
MIDDAY. CONDITIONS WILL SLOWLY IMPROVE TONIGHT WITH MOST AREAS
SCATTERING OUT EXCEPT FOR KITH/KBGM WHERE MVFR CIGS MAY LINGER IN
UPSLOPE FLOW.
NORTHWEST WINDS AT 10-15 KNOTS WITH GUSTS AROUND 25 KNOTS SLOWLY
DECREASING OVERNIGHT.
OUTLOOK...
SAT...SAT NGT...AND MOST OF SUN...VFR.
SUN NGT MON...PSBL RESTRICTIONS (MVFR/IFR) IN SNOW.
TUE...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR PAZ038>040-043-044-047-048-072.
LAKE EFFECT SNOW ADVISORY UNTIL 1 AM EST SATURDAY FOR PAZ039.
NY...WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ009-015>018-022>025-036-037-044>046-
055>057-062.
LAKE EFFECT SNOW ADVISORY UNTIL 1 AM EST SATURDAY FOR NYZ025-
055-056.
&&
$$
SYNOPSIS...TAC
NEAR TERM...MLJ/TAC
SHORT TERM...TAC
LONG TERM...MLJ/RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
836 AM EST FRI JAN 30 2015
.SYNOPSIS...
A COLD FRONT IS MOVING THROUGH THE REGION THIS MORNING. LIGHT
ACCUMULATING LAKE EFFECT SNOW WILL OCCUR TODAY. TEMPERATURES WILL
PLUMMET TODAY...WITH GUSTY WINDS SENDING WIND CHILLS WELL BELOW
ZERO TONIGHT. COLD AIR WILL REMAIN WELL INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
830 AM UPDATE... SN/+SN IS BEING OBSERVED ATTM WITHIN A SW-NE
ORIENTED BAND ACRS NE PA AND PTNS OF THE WRN CATSKILLS. THIS
FEATURE IS ON THE NWRN/DEFORMATION SIDE OF A S/WV LIFTING THROUGH
THE RGN THIS MRNG. POP/WX/SNOWFALL GRIDS WERE UPDATED TO REFLECT
SUCH DVLPMTS. WE`VE ADDED A CORRIDOR OF 2-3" ADDTNL SNOWFALL
WITHIN THE AFOREMENTIONED BAND AREA THROUGH 15-16Z. A SHORT-TERM
SPS WAS ALSO ISSUED.
OTHWS...THE FCST IS PRETTY WELL IN HAND. FAIRLY DEEP LYR OF INSTAB
NOTED ON THE 12Z KBUF SNDG...INDICATIVE OF THE AMS WE`LL HAVE
THROUGH EARLY AFTN...AHD OF THE NEXT INCOMING S/WV. LIKELY POPS
FOR SNOW SHWRS OVER MOST OF CNY...WITH MORE SCTD ACTIVITY ACRS
MUCH OF NE PA...STILL SEEMS REASONABLE...WITH A FLUFFY 1-2"
ANTICIPATED IN THE MOST PERSISTENT SHSN. IT`S WORTH NOTING THAT
THE LATEST HRRR AND HI-RES ARW OUTPUT IN PARTICULAR SHOW A WELL
FORMED MULTI-BAND/FINGER LKS BAND FROM LTR THIS MRNG...THROUGH THE
AFTN...AND INTO THE EVE HRS...DOWN THE AXIS OF CAYUGA LAKE...AND THEN
SEWD FROM THERE THROUGH AT LEAST TOMPKINS/TIOGA CNTYS. SINCE THERE
ARE ALREADY SOME INDICATIONS OF BANDING IN THIS GENERAL AREA
ATTM...WE`LL MONITOR THAT CLOSELY THROUGH THE DAY.
GIVEN STG CAA THROUGHOUT THE COLUMN...SHARPLY FALLING TEMPS STILL
LOOK LIKELY...AND OUR PREVIOUSLY ADVERTISED TREND WAS KEPT IN TACT.
PREV DISC... 3 AM UPDATE...
FRONTS MOVING THROUGH THE CWA THIS MORNING SHIFTING THE WINDS TO
WEST THEN NW. MOST OF ACCUMULATING SNOW WITH FRONTS OVER
WITH...HAVING MOVED INTO ERN NY EARLY THIS MORNING. GIVEN THE
DURATION AND THE OBS FROM SYR AND BGM PROBABLY GOT LESS THAN 4
INCHES. LAKE EFFECT WILL START WITH THE SECOND COLD FRONT. THIS
BACKED UP ALOFT WITH A SHORT WAVE AND TROF. LOW LEVEL WIND FLOW
SHIFTS FROM 280 TO 310. ALSO WINDS INCREASE TO 10 TO 20 MPH
BRINGING IN MUCH COLDER AIR. LAKE EFFECT STARTS WITH MULTIBANDS.
THIS WILL SET UP IN THE USUAL AREAS OF THE EASTERN FINGER LAKES
AND NORTHERN SUSQUEHANNA REGION. SNOW AMOUNTS WILL BE MOSTLY 1 TO
3 INCHES. THE WIND WILL CAUSE DRIFTING. SNOW AMOUNTS BELOW
ADVISORY CRITERIA SO DROPPED WWA.
TEMPERATURES TO FALL SLOWLY ALL DAY. WIND CHILLS APPROACH ZERO
THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
3 AM UPDATE...
WIND CHILL ADVISORY ISSUED FOR ENTIRE CWA. WIND CHILL TEMPS WELL
BELOW ZERO WITH TEMPERATURE FALLING INTO THE SINGLE DIGITS ABOVE
AND BELOW ZERO. WINDS ONLY SLOWLY DIMINISH TONIGHT FROM WEST TO
EAST. WINDS STAY ABOVE 10 MPH.
LAKE EFFECT SNOW WILL DIMINISH AS DRY AIR COMES IN ALOFT AND THE
DENDRITE ZONE FALLS TO THE SFC. WEAK MULTIBANDS WILL CONTINUE
MOSTLY IN THE FINGER LAKES WITH LITTLE ACCUMULATION. LOCALIZED
AMOUNTS UP TO 2 INCHES. THE LAKE EFFECT DIES SATURDAY WHEN THE LL
WINDS SHIFT.
SAT NGT A WEAK FRONT PASSES THROUGH WITH LIGHT SNOW FOR CENT NY.
FORCING AND MOISTURE LACKING IN THE NORTHERN STREAM.
MODELS HAVE TRENDED NORTH AGAIN WITH THE SUNDAY TO MONDAY STORM.
NOW NE PA COULD GET SEVERAL INCHES WITH LESSER AMOUNTS IN NY. SNOW
STARTS SUN AFTN AND CONTINUES INTO MONDAY. THE STORM TRACK IS NOW
THROUGH THE MID ATLANTIC STATES THEN SLOWING OFF THE NEW ENGLAND
COAST AS IT INTENSIFIES. STILL MUCH UNCERTAINTY...BUT UPPED POPS,
QPF, AND SNOWFALL. CONTINUE TO MENTION IN THE HWO.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
300 AM UPDATE...CURRENT FORECAST IN GOOD SHAPE JUST MINOR
ADJUSTMENTS BASED ON LATEST WPC GUIDANCE. THE GFS/ECMWF ARE STILL
IN FAIR AGREEMENT WITH THE 00Z CYCLE AND SHOW THE SFC LOW MONDAY
MORNING MOVING THROUGH NRN VA. THE CANADIAN CONTINUES TO BE
FARTHER SOUTH AS IT TRACKS THE LOW THROUGH NORTH CAROLINA. BASED
ON FAIR AGREEMENT WITH THE GFS/ECMWF FOR TWO MODEL RUNS UPPED THE
POPS TO LIKELY ACROSS THE FAR SE FA.
330 PM UPDATE... MODEL DISAGREEMENT/INCONSISTENCY CONTS WITH THE
LATEST CYCLES REGARDING THE SUN NGT-MON STORM SYSTEM. THE MOST RECENT
RUNS OF THE EC/GFS HAVE TRENDED NWD SOMEWHAT AGN...NOW TRACKING
THE SFC LOW THROUGH VA AND SERN MD...AND BRINGING LGT SNOW AT
LEAST TO THE PA/NY BORDER...IF NOT INTO NY`S SRN TIER.
MEANWHILE...THE CAN GEM HAS NOW GONE MUCH FARTHER S...TAKING THE
SFC WV THROUGH THE CAROLINAS...WITH LTL OR NO SNOWFALL FOR OUR FA.
GIVEN ALL THE UNCERTAINTY...THE EXPECTATION OF FURTHER MODEL
WAFFLING...AND ALSO THE FACT THAT THE SUPPORTING S/WV ENERGY IS
NOW JUST APPROACHING THE PACIFIC COAST OF NORTH AMERICA...WE`LL
SIMPLY MAKE VERY SMALL INCREMENTAL CHGS ATTM...JUST EASING POPS
UPWARD AGN TO INCORPORATE THE LATEST EC/GFS TRENDS. THIS RESULTS
IN LIKELY POPS FOR OUR FAR SRN ZNS SUN NGT (BACK DOWN TO CHC BY
MON)...AND CHC POPS THROUGHOUT THIS PD FOR OUR NY SRN TIER CNTYS.
ALTHOUGH...STRICTLY SPEAKING...WE`RE CURRENTLY INDICATING THE
POTENTIAL FOR A FEW INCHES OF SNOW OVER PTNS OF NE PA...THIS WILL
CERTAINLY BE SUBJECT TO CHANGE OVER THE NEXT COUPLE OF DAYS. STAY
TUNED FOR THE LATEST UPDATES ON THIS SITN.
TUE INTO WED LOOK QUIETER...BUT VERY COLD...WITH ONLY SOME FLRYS
FORESEEN AT WORST.
BY WED NGT AND THU...OUR NEXT REINFORCING COLD FRNT AND NRN STREAM
S/WV APPROACH...BRINGING A CHC OF SNOW SHWRS. THE EC IS ALSO
SHOWING THE PSBLTY THAT SOME SRN STREAM MOISTURE GETS INCORPORATED
INTO THE SYSTEM. STILL PLENTY OF TIME TO SORT ALL OF THESE FINE
DETAILS OUT.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
A STRONG COLD FRONT HAS SWEPT THROUGH ALL THE TERMINALS THIS
MORNING. NORTHWEST FLOW COMBINED WITH MOISTURE TRAPPED UNDER AN
INVERSION WILL BRING WIDESPREAD MVFR/LOW MVFR CIGS TO THE AREA
THROUGH EARLY THIS EVENING ALONG WITH OCCASIONAL SNOW SHOWERS AND
FLURRIES. AT KITH/KBGM, OCCASIONAL IFR CIGS WILL OCCUR THROUGH
MIDDAY. CONDITIONS WILL SLOWLY IMPROVE TONIGHT WITH MOST AREAS
SCATTERING OUT EXCEPT FOR KITH/KBGM WHERE MVFR CIGS MAY LINGER IN
UPSLOPE FLOW.
NORTHWEST WINDS AT 10-15 KNOTS WITH GUSTS AROUND 25 KNOTS SLOWLY
DECREASING OVERNIGHT.
OUTLOOK...
SAT...SAT NGT...AND MOST OF SUN...VFR.
SUN NGT MON...PSBL RESTRICTIONS (MVFR/IFR) IN SNOW.
TUE...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR PAZ038>040-043-044-047-048-072.
NY...WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR NYZ009-015>018-022>025-036-037-044>046-
055>057-062.
&&
$$
SYNOPSIS...TAC
NEAR TERM...MLJ/TAC
SHORT TERM...TAC
LONG TERM...MLJ/RRM
AVIATION...RRM
PREVIOUS FORECAST DISCUSSION...
SURFACE LOW IS MOVING INTO SOUTHERN ONTARIO WITH PRECIP SPREADING
EAST ACROSS NY. AT THIS POINT A LITTLE LIGHT SNOW IN THE CWA HAS
BEEN CONFINED MAINLY TO THE NORTHERN ZONES AS THERE IS A LOT OF
LOW LEVEL DRY AIR IN PLACE FARTHER SOUTH. HOWEVER MAIN BATCH OF
PRECIP NOW AROUND BUFFALO WILL MOVE EAST WITH LIGHT SNOW MOVING
INTO REMAINING AREAS OF THE CWA TOWARD THE LATE AFTERNOON / EARLY
EVENING TIME FRAME AS LOW LEVELS SATURATE.
EXPECT LIGHT SNOW TO CONTINUE THROUGH MOST OF THE NIGHT AS THE LOW MOVES
EAST WITH THE HEAVIEST AMOUNTS OVER NORTHERN PARTS OF THE CWA FROM
ONONDAGA EAST THROUGH ONEIDA COUNTIES...AS DYNAMICS WILL BE
STRONGEST HERE...AND THERE WILL ALSO BE ADDED OROGRAPHIC LIFT IN
THE TUG HILL PLATEAU REGION. NAM AND RAP SEEM TO BE HANDLING THIS
FAIRLY WELL SO LEANED FORECAST TOWARD THESE MODELS. THE LOW WILL
DRAG A COLD FRONT THROUGH LATE TONIGHT SHIFTING THE WINDS TO THE
NW AND STARTING THE LAKE EFFECT MACHINE. ARCTIC AIR RETURNS
QUICKLY FRIDAY UNDER AN UPPER LEVEL TROF WITH FALLING TEMPS
THROUGH THE DAY. MODERATE SW WINDS WILL SHIFT TO STRONGER NW WINDS
LATE TONIGHT AND CREATE DRIFTING AND BLOWING SNOW.
WITH A NW LL FLOW FRIDAY LAKE EFFECT FRIDAY WILL BE ACROSS THE USUAL
AREAS OF CENTRAL NY. CAA WILL INCREASE LAPSE RATES ESPECIALLY IN
THE AFTN. AT THE SAME TIME THE INVERSION AND DENDRITE ZONE LOWER.
MULTI BAND LES COULD BE BRIEFLY HEAVY.
A WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR THE NRN THIRD OF THE CWA
FOR THE SYNOPTIC SNOW OF 2 TO 5 INCHES TONIGHT FOLLOWED BY
ANOTHER 1 TO 4 INCHES OF LES FRIDAY. IN ADDITION WIND GUSTS TO 35
WILL CAUSE BLOWING AND DRIFTING SNOW FRIDAY. FURTHER SOUTH, WE GENERALLY
EXPECT SNOW AMOUNTS THROUGH FRIDAY OF 1 TO 3 INCHES FROM NE PA
THROUGH THE SOUTHERN TIER OF NY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
315 PM UPDATE... LINGERING MULTI-BAND LES ACRS CNY AND PA`S NRN
TIER FRI EVE...WILL SLOWLY DIMINISH OVERNIGHT...AS THE CAPPING
INVERSION LWRS. ANOTHER LOCALIZED 1-2" MAY ACCUMULATE FRI NGT OVER
THE HIGHER TERRAIN OF THE UPR SUSQ/FINGER LKS RGNS IN CNY.
VERY COLD WIND CHILL READINGS ARE DEFINITELY A CONCERN FRI
NGT...WITH SFC WINDS ONLY SLOWLY SUBSIDING...AND ACTUAL AIR TEMPS
DROPPING INTO THE 5 ABV TO 10 BLO RANGE. WE`LL CONTINUE TO
HIGHLIGHT THIS SITN IN THE HWO...CITING THE POTENTIAL FOR WC
ADVSYS OR WRNGS IN LATER FCST UPDATES.
OTHER THAN PERHAPS A FEW FLRYS ON SAT...THE DAY SHOULD BE LARGELY
DRY...WITH BRIEF RIDGING AT THE SFC AND SOME S/WV RIDGING ALOFT
ACRS THE FA.
SAT NGT INTO SUN MRNG...A WEAK NRN STREAM S/WV AND SFC FRNT WILL
PUSH SWD THROUGH CNY/NE PA...ACCOMPANIED BY FLRYS AND SCTD LGT
SNOW SHWRS (LTL OR NO ACCUMS).
BY LATER SUN AFTN...WE MAY SEE SOME STEADIER LGT SNOW APPROACH OUR
FAR SWRN ZNS...ON THE OUTER EDGES OF THE NEXT S/WV AND FAST MOVG
SFC WV. MORE ON THIS SYSTEM IN THE FOLLOWING SXN.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
300 AM UPDATE...CURRENT FORECAST IN GOOD SHAPE JUST MINOR
ADJUSTMENTS BASED ON LATEST WPC GUIDANCE. THE GFS/ECMWF ARE STILL
IN FAIR AGREEMENT WITH THE 00Z CYCLE AND SHOW THE SFC LOW MONDAY
MORNING MOVING THROUGH NRN VA. THE CANADIAN CONTINUES TO BE
FARTHER SOUTH AS IT TRACKS THE LOW THROUGH NORTH CAROLINA. BASED
ON FAIR AGREEMENT WITH THE GFS/ECMWF FOR TWO MODEL RUNS UPPED THE
POPS TO LIKELY ACROSS THE FAR SE FA.
330 PM UPDATE... MODEL DISAGREEMENT/INCONSISTENCY CONTS WITH THE
LATEST CYCLES REGARDING THE SUN NGT-MON STORM SYSTEM. THE MOST RECENT
RUNS OF THE EC/GFS HAVE TRENDED NWD SOMEWHAT AGN...NOW TRACKING
THE SFC LOW THROUGH VA AND SERN MD...AND BRINGING LGT SNOW AT
LEAST TO THE PA/NY BORDER...IF NOT INTO NY`S SRN TIER.
MEANWHILE...THE CAN GEM HAS NOW GONE MUCH FARTHER S...TAKING THE
SFC WV THROUGH THE CAROLINAS...WITH LTL OR NO SNOWFALL FOR OUR FA.
GIVEN ALL THE UNCERTAINTY...THE EXPECTATION OF FURTHER MODEL
WAFFLING...AND ALSO THE FACT THAT THE SUPPORTING S/WV ENERGY IS
NOW JUST APPROACHING THE PACIFIC COAST OF NORTH AMERICA...WE`LL
SIMPLY MAKE VERY SMALL INCREMENTAL CHGS ATTM...JUST EASING POPS
UPWARD AGN TO INCORPORATE THE LATEST EC/GFS TRENDS. THIS RESULTS
IN LIKELY POPS FOR OUR FAR SRN ZNS SUN NGT (BACK DOWN TO CHC BY
MON)...AND CHC POPS THROUGHOUT THIS PD FOR OUR NY SRN TIER CNTYS.
ALTHOUGH...STRICTLY SPEAKING...WE`RE CURRENTLY INDICATING THE
POTENTIAL FOR A FEW INCHES OF SNOW OVER PTNS OF NE PA...THIS WILL
CERTAINLY BE SUBJECT TO CHANGE OVER THE NEXT COUPLE OF DAYS. STAY
TUNED FOR THE LATEST UPDATES ON THIS SITN.
TUE INTO WED LOOK QUIETER...BUT VERY COLD...WITH ONLY SOME FLRYS
FORESEEN AT WORST.
BY WED NGT AND THU...OUR NEXT REINFORCING COLD FRNT AND NRN STREAM
S/WV APPROACH...BRINGING A CHC OF SNOW SHWRS. THE EC IS ALSO
SHOWING THE PSBLTY THAT SOME SRN STREAM MOISTURE GETS INCORPORATED
INTO THE SYSTEM. STILL PLENTY OF TIME TO SORT ALL OF THESE FINE
DETAILS OUT.
&&
.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
A STRONG COLD FRONT WILL CROSS THE REGION EARLY THIS MORNING
BETWEEN 09Z-11Z. THROUGH DAYBREAK WIDESPREAD LOW MVFR CONDITIONS
ARE EXPECTED ALONG WITH OCCASIONAL IFR/BELOW ALT MIN CONDITIONS IN
THE HEAVIER SNOW SHOWERS. ONCE THE FRONT PASSES LOW MVFR CIGS ARE
FORECAST FOR THE DAYLIGHT HOURS WITH MVFR AT KELM/KAVP. DUE TO
STRONG NORTHWEST WINDS LAKE EFFECT SNOW SHOWERS WILL BRING
OCCASIONAL IFR SNOW SHOWERS TO KSYR/KRME/KITH UNTIL MIDDAY. THIS
EVENING CONDITIONS WILL GRADUALLY IMPROVE BUT THROUGH 06Z MVFR
CIGS WILL PERSIST.
S/SW WINDS AROUND 10 KNOTS BECOMING NORTHWEST EARLY THIS MORNING
AT 10-15 KNOTS WITH GUSTS AROUND 25 KNOTS.
OUTLOOK...
SAT...SAT NGT...AND MOST OF SUN...VFR.
SUN NGT MON...PSBL RESTRICTIONS (MVFR/IFR) IN SNOW.
TUE...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...WINTER WEATHER ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR
NYZ009-016>018-036-037-044>046.
&&
$$
SYNOPSIS...PCF
NEAR TERM...KAH/PCF
SHORT TERM...MLJ
LONG TERM...MLJ/RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
314 PM EST FRI JAN 30 2015
.SYNOPSIS...BREEZY NORTHWESTERLY WINDS TODAY WILL GIVE WAY TO HIGH
PRESSURE BUILDING IN FROM THE WEST OVER THE WEEKEND. A LOW PRESSURE
SYSTEM WILL THEN CROSS THE REGION LATE SUNDAY AND MONDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1030 AM FRIDAY...
AN UPPER TROUGH IS CURRENTLY SWINGING ACROSS THE AREA WITH A COLD
FRONT DEPARTING TO THE EAST. STRONG POST-FRONTAL COLD ADVECTION IS
SETTING UP ACROSS THE AREA THIS MORNING WITH THE 12Z KGSO RAOB
SHOWING AN ALREADY DEEP MIXED LAYER UP TO 5000 FT AND A GUST TO 38KT
AT KGSO. NORTHWESTERLY WINDS ARE STEADILY INCREASING AND GUSTS ARE
STARTING TO REACH THE UPPER 20S TO AROUND 30KT AREAWIDE. IT APPEARS
THE GUSTS WILL PEAK LATE THIS MORNING AND VERY EARLY AFTERNOON...AS
MUCH AS 30-35KT IN SOME AREAS...BEFORE THE PRESSURE GRADIENT BEGINS
TO SLOWLY WEAKEN. MEANWHILE...REGIONAL VIS SHOWS A FEW STREAMS OF
MOISTURE (JUST ABOVE 850MB PER KGSO/KRNK RAOBS) SPILLING EAST ACROSS
THE NORTHERN CWA. THE STRONG INVERSION JUST ABOVE AND STRENGTHENING
SUBSIDENCE BEHIND THE UPPER TROUGH WILL KEEP THIS MOISTURE TRAPPED
AND THE STRATOCU FAIRLY SHALLOW...SO WE MAINLY EXPECT SKIES VARYING
FROM PARTLY CLOUDY SOUTHWEST TO A PERIOD OF MOSTLY CLOUDY NORTHEAST.
DRY ADIABATIC MIXING TO 850MB WHILE ACCOUNTING FOR SOME DOWNSLOPE
WARMING YIELDS HIGHS IN THE 43-50 RANGE...ONLY ABOUT 3-4 DEGREES OFF
CURRENT READINGS. -BLS
&&
.SHORT TERM /TONIGHT THROUGH MONDAY/...
AS OF 308 PM FRIDAY...
WINDS WILL DIMINISH TONIGHT UNDER CLEAR SKIES. THERE SHOULD BE
ENOUGH OF A GRADIENT FOR AT LEAST A SLIGHT STIR TO THE WIND THROUGH
THE NIGHT...AS 925MB WINDS REMAIN TO 35KT. SURFACE DEW POINTS SHOULD
CONTINUE TO DRY...AND 1000-850MB THICKNESSES WOULD SUGGEST LOWS FROM
THE TEENS TO THE LOWER 20S. THIS WILL ESSENTIALLY BE THE FORECAST
FOR LOWS OVERNIGHT...19 TO 20 IN THE NORTHWEST PIEDMONT TO NEAR 25
TOWARD KFAY...CLOSE TO THE AVERAGE OF THE MET AND MAV MOS. ON
SATURDAY...925MB WINDS DIMINISH TO AROUND 15KT BY 18Z...AND BUFR
SOUNDINGS FROM BOTH THE NAM AND GFS SUGGEST A FEW WIND GUSTS IN THE
TEENS KNOTS WITH INITIAL MIXING BEFORE THE WINDS DIMINISH AS HIGH
PRESSURE CONTINUES TO BUILD IN FROM THE NORTHWEST.
SATURDAY AFTERNOON...A FLAT RIDGE AXIS ALOFT GETS CLOSE TO CENTRAL
NORTH CAROLINA AS SOME MID-LEVEL VORTICITY ADVECTION MOVES INTO AND
ACROSS CENTRAL NORTH CAROLINA DURING THE LATE AFTERNOON AND
NIGHTTIME HOURS...FORECAST BY BOTH THE GFS AND NAM. GFS AND NAM BUFR
SOUNDINGS SUGGEST INCREASING UPPER-LEVEL MOISTURE SUCH THAT
INCREASING HIGH CLOUDS SHOULD GRADUALLY OCCUR FROM SATURDAY
AFTERNOON INTO SATURDAY NIGHT. WITH MOST IF NOT ALL OF CENTRAL NORTH
CAROLINA EXPECTED TO BE MOSTLY CLOUDY BY THE MIDDLE OF THE NIGHT
SATURDAY...OVERNIGHT LOWS SHOULD BE WARMER...MID TO UPPER 20S IN THE
NORTHERN COASTAL PLAIN TO AROUND 30 ELSEWHERE. -DJF
HIGH PRESSURE WILL MOVE OFF THE EAST COAST SUNDAY... AS A LOW
PRESSURE SYSTEM MOVES INTO THE OHIO VALLEY. SOUTHWESTERLY LOW LEVEL
FLOW... AND INCREASING THICKNESSES WILL BRING HIGHS A FEW DEGREES
WARMER ON SUNDAY... AROUND 50. COLD FRONT WILL MOVE THROUGH THE AREA
ON MONDAY. A STRONG PRESSURE GRADIENT WILL DEVELOP AS THE LOW
DEEPENS OFF THE MIDATLANTIC COAST... AND HIGH PRESSURE BUILDS IN TO
THE MIDWEST... LEADING TO BREEZY CONDITIONS MONDAY AFTERNOON. STRONG
COLD ADVECTION WILL OVERTAKE THE REGION DURING THIS TIME... LEADING
TO A LIKELY NONDIURNAL TEMPERATURE TREND... WITH TEMPS FALLING
THROUGH THE 40S DURING THE DAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 309 PM FRIDAY...
HIGH PRESSURE WILL EXTEND ACROSS THE AREA TUESDAY AND WEDNESDAY...
AS ENERGY CURRENTLY OVER THE BAJA MOVES EASTWARD TO THE GULF COAST.
AN AREA OF LOW PRESSURE WILL DEVELOP IN RESPONSE OVER THE NORTHERN
GULF OF MEXICO ON WEDNESDAY... POTENTIALLY MOVING ALONG THE
SOUTHEAST COAST IN THE THURS/FRI TIMEFRAME. GFS REMAINS CLOSE TO THE
COAST WITH PRECIP MOVING IN LATER ON WEDNESDAY... 12Z ECMWF TAKES
THE LOW OUT TO SEA WITH LITTLE LOCAL IMPACT... AND GFS ENSEMBLE HAS
CONSIDERABLE VARIATION IN STRENGTH AND PROXIMITY TO THE COAST... SO
CONFIDENCE AT THIS TIME REMAINS LOW. TIMING WILL HAVE A GREAT IMPACT
ON PTYPE... WITH ANY OVERNIGHT PRECIP POTENTIALLY BRINGING PTYPE
ISSUES. AT THIS POINT... WILL CONTINUE WITH CHANCE OF RAIN UNTIL
TIMING/DEVELOPMENT CAN BE BETTER ASCERTAINED. TEMPERATURES WILL
CONTINUE TO BE BELOW NORMAL THROUGH THE END OF THE WEEK.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 100 PM FRIDAY...
STRONG NORTHWESTERLY WIND GUSTS (CROSSWINDS FOR MANY RUNWAYS) OF
ANYWHERE FROM 25KT TO 35KT ARE OCCURRING ACROSS CENTRAL NC THIS
MORNING IN THE WAKE OF A DEPARTING COLD FRONT. THESE GUSTS WILL
CONTINUE THIS AFTERNOON AND MAY LINGER INTO THE EVENING HOURS BEFORE
SUBSIDING AFTER MIDNIGHT. SCATTERED STRATOCU WILL BE MOSTLY
CONCENTRATED FROM KRDU NORTH AND EAST BUT REMAIN ABOVE 5000 FT THIS
AFTERNOON. OTHERWISE...HIGH PRESSURE WILL BUILD IN FROM THE WEST
THROUGH SATURDAY AND VFR CONDITIONS ARE EXPECTED TO PREVAIL.
BEYOND THE 12Z VALID TAF PERIOD... VFR CONDITIONS WILL CONTINUE
THROUGH EARLY SUNDAY. A LOW PRESSURE SYSTEM WILL CROSS THE CENTRAL
APPALACHIANS SUNDAY NIGHT...WITH A CHANCE OF RAIN AND SUB-VFR
CONDITIONS FROM LATE SUNDAY AFTERNOON THROUGH MONDAY AFTERNOON.
HIGH PRESSURE AND VFR CONDITIONS WILL RETURN FOR TUESDAY...WITH
ANOTHER SYSTEM TO APPROACH THE REGION ON WEDNESDAY.
&&
.FIRE WEATHER...
AS OF 300 AM FRIDAY...
WIND GUSTS TO 30KT TODAY...OR TO AROUND 35 MPH...ARE CERTAINLY
POSSIBLE AS THE SURFACE GRADIENT TIGHTENS BEHIND THE COLD FRONT.
SURFACE DEW POINTS WILL FALL BEHIND THE FRONT AS WELL...WITH THE
LOWEST GUIDANCE OF THE RAP SUGGESTING SOME DEW POINTS IN SINGLE
FIGURES LATE IN THE DAY IN THE NORTHWEST PIEDMONT. THE GFS IS
HIGHER...AND THE NAM IS MORE OF A COMPROMISE...WHICH IS CONSISTENT
WITH THE MOS GUIDANCE. BY 00Z SATURDAY...THE GRIDDED FORECAST WILL
SHOW A DEW POINT NEAR 10F IN THE TRIAD...BUT EVEN THERE THE MINIMUM
RELATIVE HUMIDITY IS IN THE UPPER 20S PERCENT. BASED THOSE DEW
POINTS...RECENT RAIN...AND EARLIER FORECAST SERVICE COORDINATION...
WILL FOR NOW HIGHLIGHT THE ADVERSE CONDITIONS OF THE WIND GUSTS IN
THE DISCUSSION OF THE FIRE WEATHER FORECAST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF/BLS
SHORT TERM...DJF/SEC
LONG TERM...SEC
AVIATION...BLS
FIRE WEATHER...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
100 PM EST FRI JAN 30 2015
.SYNOPSIS...BREEZY NORTHWESTERLY WINDS TODAY WILL GIVE WAY TO HIGH
PRESSURE BUILDING IN FROM THE WEST OVER THE WEEKEND. A LOW PRESSURE
SYSTEM WILL THEN CROSS THE REGION LATE SUNDAY AND MONDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1030 AM FRIDAY...
AN UPPER TROUGH IS CURRENTLY SWINGING ACROSS THE AREA WITH A COLD
FRONT DEPARTING TO THE EAST. STRONG POST-FRONTAL COLD ADVECTION IS
SETTING UP ACROSS THE AREA THIS MORNING WITH THE 12Z KGSO RAOB
SHOWING AN ALREADY DEEP MIXED LAYER UP TO 5000 FT AND A GUST TO 38KT
AT KGSO. NORTHWESTERLY WINDS ARE STEADILY INCREASING AND GUSTS ARE
STARTING TO REACH THE UPPER 20S TO AROUND 30KT AREAWIDE. IT APPEARS
THE GUSTS WILL PEAK LATE THIS MORNING AND VERY EARLY AFTERNOON...AS
MUCH AS 30-35KT IN SOME AREAS...BEFORE THE PRESSURE GRADIENT BEGINS
TO SLOWLY WEAKEN. MEANWHILE...REGIONAL VIS SHOWS A FEW STREAMS OF
MOISTURE (JUST ABOVE 850MB PER KGSO/KRNK RAOBS) SPILLING EAST ACROSS
THE NORTHERN CWA. THE STRONG INVERSION JUST ABOVE AND STRENGTHENING
SUBSIDENCE BEHIND THE UPPER TROUGH WILL KEEP THIS MOISTURE TRAPPED
AND THE STRATOCU FAIRLY SHALLOW...SO WE MAINLY EXPECT SKIES VARYING
FROM PARTLY CLOUDY SOUTHWEST TO A PERIOD OF MOSTLY CLOUDY NORTHEAST.
DRY ADIABATIC MIXING TO 850MB WHILE ACCOUNTING FOR SOME DOWNSLOPE
WARMING YIELDS HIGHS IN THE 43-50 RANGE...ONLY ABOUT 3-4 DEGREES OFF
CURRENT READINGS. -BLS
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...
WINDS WILL DIMINISH TONIGHT UNDER CLEAR SKIES. THERE SHOULD BE
ENOUGH OF A GRADIENT FOR AT LEAST A SLIGHT STIR TO THE WIND THROUGH
THE NIGHT...AS 925MB WINDS REMAIN TO 35KT. SURFACE DEW POINTS SHOULD
CONTINUE TO DRY...AND 1000-850MB THICKNESSES WOULD SUGGEST LOWS FROM
THE TEENS TO THE LOWER 20S. THIS WILL ESSENTIALLY BE THE FORECAST
FOR LOWS OVERNIGHT...19 TO 20 IN THE NORTHWEST PIEDMONT TO NEAR 25
TOWARD KFAY...CLOSE TO THE AVERAGE OF THE MET AND MAV MOS. ON
SATURDAY...925MB WINDS DIMINISH TO AROUND 15KT BY 18Z...AND BUFR
SOUNDINGS FROM BOTH THE NAM AND GFS SUGGEST A FEW WIND GUSTS IN THE
TEENS KNOTS WITH INITIAL MIXING BEFORE THE WINDS DIMINISH AS HIGH
PRESSURE CONTINUES TO BUILD IN FROM THE NORTHWEST.
SATURDAY AFTERNOON...A FLAT RIDGE AXIS ALOFT GETS CLOSE TO CENTRAL
NORTH CAROLINA AS SOME MID-LEVEL VORTICITY ADVECTION MOVES INTO AND
ACROSS CENTRAL NORTH CAROLINA DURING THE LATE AFTERNOON AND
NIGHTTIME HOURS...FORECAST BY BOTH THE GFS AND NAM. GFS AND NAM BUFR
SOUNDINGS SUGGEST INCREASING UPPER-LEVEL MOISTURE SUCH THAT
INCREASING HIGH CLOUDS SHOULD GRADUALLY OCCUR FROM SATURDAY
AFTERNOON INTO SATURDAY NIGHT. WITH MOST IF NOT ALL OF CENTRAL NORTH
CAROLINA EXPECTED TO BE MOSTLY CLOUDY BY THE MIDDLE OF THE NIGHT
SATURDAY...OVERNIGHT LOWS SHOULD BE WARMER...MID TO UPPER 20S IN THE
NORTHERN COASTAL PLAIN TO AROUND 30 ELSEWHERE. -DJF
MINOR MID-LEVEL IMPULSES EMANATING FROM THE UPPER TROUGH/CLOSED LOW
OVER THE SOUTHWEST US WILL GET KICKED EASTWARD...IN ADVANCE OF AN
AMPLIFYING NORTHERN STREAM OVER THE CENTRAL PLAINS...ON SUNDAY.
ASSOCIATED CYCLOGENESIS WILL TRACK EASTWARD ACROSS THE LOWER MS
VALLEY/TN VALLEY ON SUNDAY...THEN ACROSS THE CAROLINAS/VIRGINIA
SUNDAY NIGHT BEFORE MOVING OFF THE MID-ATLANTIC COAST MONDAY
MORNING.
NWP MODEL GUIDANCE CONTINUES TO EXHIBIT CONSIDERABLE SPREAD WITH THE
TRACK OF THE SURFACE LOW AS IT MOVES THROUGH THE REGION SUNDAY
NIGHT...WITH A DEFINITE NORTHWARD SHIFT OBSERVED IN THE LATEST
00Z/30 MODEL ITERATION. THIS RESULTS IN A SLIGHTLY SLOWER/DELAYED
ONSET OF PRECIP ACROSS THE AREA LATE SUNDAY AFTERNOON AND
EVENING...BUT IMPORTANTLY DISPLACES THE HEAVIER QPF NORTH OF THE
AREA.
AS SUCH...SUNDAY WILL END UP MOSTLY DRY ACROSS CENTRAL NC WITH
THICKENING CLOUD COVER THROUGH THE AFTERNOON WITH HIGHS RANGING FROM
MID 40S NORTH TO LOWER 50S SOUTH. RAIN CHANCES WILL QUICKLY RAMP UP
SUNDAY EVENING...WITH CATEGORICAL POPS SUNDAY NIGHT...CUTTING OFF
FROM WEST TO EAST MORNING MONDAY AS THE MID-LEVEL DRY SLOT RACES
EASTWARD. ESTIMATED QPF AMOUNTS NOW LOOK TO BE IN THE 0.25-0.50"
RANGE. WITH ONLY WEAK ELEVATED INSTABILITY AT BEST EXPECTED ACROSS
THE COASTAL PLAIN AND WITH THE SURFACE LOW NOW DISPLACED NORTH OF
THE AREA...WILL KEEP OUT THE MENTION OF ANY THUNDER ACROSS THE
EASTERN ZONES.
EXPECT A NON-DIURNAL TEMP TREND SUNDAY NIGHT...WITH LOWS OCCURRING
BEFORE MIDNIGHT...THEN TEMPERATURES WARMING OVERNIGHT OWING TO
STRONG WAA. LOWS SUNDAY NIGHT IN THE LOWER 40S NORTHWEST TO UPPER
40S SOUTHEAST. -CBL
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...
MONDAY THROUGH TUESDAY: AGGRESSIVE MID-LEVEL DRY AIR INTRUSION WILL
OVERTAKE THE AREA FROM THE WEST BETWEEN 12 TO 18Z MONDAY IN ADVANCE
OF THE PASSAGE OF THE NORTHERN STREAM TROUGH PASSAGE MONDAY
AFTERNOON. THIS WILL BRING AN ABRUPT END TO PRECIP ACROSS THE AREA
MONDAY MORNING...WITH RAIN/SHOWERS EXITING THE COASTAL PLAIN BY MID
TO LATE MORNING. EQUALLY IMPRESSIVE WILL BE STRONG POST-FRONTAL DRY
COLD AIR ADVECTION REGIME...WITH TEMPERATURES FALLING BY THE
AFTERNOON AS CONTINENTAL POLAR HIGH PRESSURE BUILDS INTO THE AREA
MONDAY NIGHT AND INTO THE DAY ON TUESDAY. IF PROJECTED LOW-LEVEL
THICKNESSES VERIFY AND WE DECOUPLE AS THE SURFACE HIGH MOVES
OVERHEAD... EXPECT LOWS TUESDAY MORNING IN THE UPPER TEENS TO LOWER
20S. UNDER FULL COMPLIMENTS OF SUN...TEMPS TUESDAY WILL STRUGGLE TO
WARM THROUGH THE 30S. HIGHS RANGING FROM MID/UPPER 30S NORTH TO
LOWER 40S SOUTH.
WEDNESDAY THROUGH THURSDAY: MODEL SPREAD REMAINS HIGH WITH THE
EVOLUTION OF THE SLOW MOVING UPPER LOW/TROUGH EJECTING EASTWARD FROM
MEXICO AND SUBSEQUENT DEVELOPMENT OF A LOW PRESSURE AREA TRACKING
ALONG THE SOUTHEAST COAST. IN A COMPLETE ROLE REVERSAL... THE GFS IS
NOW MORE PROGRESSIVE THAN THE EC WITH BRINGING PRECIP BACK INTO THE
AREA DURING THE DAY ON WEDNESDAY...WITH THE EC NEARLY 24 HOURS
SLOWER...DELAYING UNTIL THURSDAY. GIVEN LATER TIMING OF ONSET OF
PRECIP...LOW-LEVEL THICKNESSES CURRENTLY SUPPORT ALL RAIN. HOWEVER
IF FUTURE MODEL RUNS SPEED UP THE TIMING OF THE SYSTEM...ANY PRECIP
INTO THE AREA TUESDAY NIGHT/EARLY WEDNESDAY MORNING COULD BE OF THE
FROZEN VARIETY. WILL CONTINUE TO MONITOR TRENDS...BUT FOR NOW GIVEN
UNCERTAINTY WILL KEEP POPS AT SMALL CHANCE FOR WEDNESDAY AND
THURSDAY WITH A CONTINUATION OF BELOW NORMAL TEMPERATURES.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 100 PM FRIDAY...
STRONG NORTHWESTERLY WIND GUSTS (CROSSWINDS FOR MANY RUNWAYS) OF
ANYWHERE FROM 25KT TO 35KT ARE OCCURRING ACROSS CENTRAL NC THIS
MORNING IN THE WAKE OF A DEPARTING COLD FRONT. THESE GUSTS WILL
CONTINUE THIS AFTERNOON AND MAY LINGER INTO THE EVENING HOURS BEFORE
SUBSIDING AFTER MIDNIGHT. SCATTERED STRATOCU WILL BE MOSTLY
CONCENTRATED FROM KRDU NORTH AND EAST BUT REMAIN ABOVE 5000 FT THIS
AFTERNOON. OTHERWISE...HIGH PRESSURE WILL BUILD IN FROM THE WEST
THROUGH SATURDAY AND VFR CONDITIONS ARE EXPECTED TO PREVAIL.
BEYOND THE 12Z VALID TAF PERIOD... VFR CONDITIONS WILL CONTINUE
THROUGH EARLY SUNDAY. A LOW PRESSURE SYSTEM WILL CROSS THE CENTRAL
APPALACHIANS SUNDAY NIGHT...WITH A CHANCE OF RAIN AND SUB-VFR
CONDITIONS FROM LATE SUNDAY AFTERNOON THROUGH MONDAY AFTERNOON.
HIGH PRESSURE AND VFR CONDITIONS WILL RETURN FOR TUESDAY...WITH
ANOTHER SYSTEM TO APPROACH THE REGION ON WEDNESDAY.
&&
.FIRE WEATHER...
AS OF 300 AM FRIDAY...
WIND GUSTS TO 30KT TODAY...OR TO AROUND 35 MPH...ARE CERTAINLY
POSSIBLE AS THE SURFACE GRADIENT TIGHTENS BEHIND THE COLD FRONT.
SURFACE DEW POINTS WILL FALL BEHIND THE FRONT AS WELL...WITH THE
LOWEST GUIDANCE OF THE RAP SUGGESTING SOME DEW POINTS IN SINGLE
FIGURES LATE IN THE DAY IN THE NORTHWEST PIEDMONT. THE GFS IS
HIGHER...AND THE NAM IS MORE OF A COMPROMISE...WHICH IS CONSISTENT
WITH THE MOS GUIDANCE. BY 00Z SATURDAY...THE GRIDDED FORECAST WILL
SHOW A DEW POINT NEAR 10F IN THE TRIAD...BUT EVEN THERE THE MINIMUM
RELATIVE HUMIDITY IS IN THE UPPER 20S PERCENT. BASED THOSE DEW
POINTS...RECENT RAIN...AND EARLIER FORECAST SERVICE COORDINATION...
WILL FOR NOW HIGHLIGHT THE ADVERSE CONDITIONS OF THE WIND GUSTS IN
THE DISCUSSION OF THE FIRE WEATHER FORECAST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF/BLS
SHORT TERM...DJF/CBL
LONG TERM...CBL
AVIATION...BLS
FIRE WEATHER...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1030 AM EST FRI JAN 30 2015
.SYNOPSIS...BREEZY NORTHWESTERLY WINDS TODAY WILL GIVE WAY TO HIGH
PRESSURE BUILDING IN FROM THE WEST OVER THE WEEKEND. A LOW PRESSURE
SYSTEM WILL THEN CROSS THE REGION LATE SUNDAY AND MONDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1030 AM FRIDAY...
AN UPPER TROUGH IS CURRENTLY SWINGING ACROSS THE AREA WITH A COLD
FRONT DEPARTING TO THE EAST. STRONG POST-FRONTAL COLD ADVECTION IS
SETTING UP ACROSS THE AREA THIS MORNING WITH THE 12Z KGSO RAOB
SHOWING AN ALREADY DEEP MIXED LAYER UP TO 5000 FT AND A GUST TO 38KT
AT KGSO. NORTHWESTERLY WINDS ARE STEADILY INCREASING AND GUSTS ARE
STARTING TO REACH THE UPPER 20S TO AROUND 30KT AREAWIDE. IT APPEARS
THE GUSTS WILL PEAK LATE THIS MORNING AND VERY EARLY AFTERNOON...AS
MUCH AS 30-35KT IN SOME AREAS...BEFORE THE PRESSURE GRADIENT BEGINS
TO SLOWLY WEAKEN. MEANWHILE...REGIONAL VIS SHOWS A FEW STREAMS OF
MOISTURE (JUST ABOVE 850MB PER KGSO/KRNK RAOBS) SPILLING EAST ACROSS
THE NORTHERN CWA. THE STRONG INVERSION JUST ABOVE AND STRENGTHENING
SUBSIDENCE BEHIND THE UPPER TROUGH WILL KEEP THIS MOISTURE TRAPPED
AND THE STRATOCU FAIRLY SHALLOW...SO WE MAINLY EXPECT SKIES VARYING
FROM PARTLY CLOUDY SOUTHWEST TO A PERIOD OF MOSTLY CLOUDY NORTHEAST.
DRY ADIABATIC MIXING TO 850MB WHILE ACCOUNTING FOR SOME DOWNSLOPE
WARMING YIELDS HIGHS IN THE 43-50 RANGE...ONLY ABOUT 3-4 DEGREES OFF
CURRENT READINGS. -BLS
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...
WINDS WILL DIMINISH TONIGHT UNDER CLEAR SKIES. THERE SHOULD BE
ENOUGH OF A GRADIENT FOR AT LEAST A SLIGHT STIR TO THE WIND THROUGH
THE NIGHT...AS 925MB WINDS REMAIN TO 35KT. SURFACE DEW POINTS SHOULD
CONTINUE TO DRY...AND 1000-850MB THICKNESSES WOULD SUGGEST LOWS FROM
THE TEENS TO THE LOWER 20S. THIS WILL ESSENTIALLY BE THE FORECAST
FOR LOWS OVERNIGHT...19 TO 20 IN THE NORTHWEST PIEDMONT TO NEAR 25
TOWARD KFAY...CLOSE TO THE AVERAGE OF THE MET AND MAV MOS. ON
SATURDAY...925MB WINDS DIMINISH TO AROUND 15KT BY 18Z...AND BUFR
SOUNDINGS FROM BOTH THE NAM AND GFS SUGGEST A FEW WIND GUSTS IN THE
TEENS KNOTS WITH INITIAL MIXING BEFORE THE WINDS DIMINISH AS HIGH
PRESSURE CONTINUES TO BUILD IN FROM THE NORTHWEST.
SATURDAY AFTERNOON...A FLAT RIDGE AXIS ALOFT GETS CLOSE TO CENTRAL
NORTH CAROLINA AS SOME MID-LEVEL VORTICITY ADVECTION MOVES INTO AND
ACROSS CENTRAL NORTH CAROLINA DURING THE LATE AFTERNOON AND
NIGHTTIME HOURS...FORECAST BY BOTH THE GFS AND NAM. GFS AND NAM BUFR
SOUNDINGS SUGGEST INCREASING UPPER-LEVEL MOISTURE SUCH THAT
INCREASING HIGH CLOUDS SHOULD GRADUALLY OCCUR FROM SATURDAY
AFTERNOON INTO SATURDAY NIGHT. WITH MOST IF NOT ALL OF CENTRAL NORTH
CAROLINA EXPECTED TO BE MOSTLY CLOUDY BY THE MIDDLE OF THE NIGHT
SATURDAY...OVERNIGHT LOWS SHOULD BE WARMER...MID TO UPPER 20S IN THE
NORTHERN COASTAL PLAIN TO AROUND 30 ELSEWHERE. -DJF
MINOR MID-LEVEL IMPULSES EMANATING FROM THE UPPER TROUGH/CLOSED LOW
OVER THE SOUTHWEST US WILL GET KICKED EASTWARD...IN ADVANCE OF AN
AMPLIFYING NORTHERN STREAM OVER THE CENTRAL PLAINS...ON SUNDAY.
ASSOCIATED CYCLOGENESIS WILL TRACK EASTWARD ACROSS THE LOWER MS
VALLEY/TN VALLEY ON SUNDAY...THEN ACROSS THE CAROLINAS/VIRGINIA
SUNDAY NIGHT BEFORE MOVING OFF THE MID-ATLANTIC COAST MONDAY
MORNING.
NWP MODEL GUIDANCE CONTINUES TO EXHIBIT CONSIDERABLE SPREAD WITH THE
TRACK OF THE SURFACE LOW AS IT MOVES THROUGH THE REGION SUNDAY
NIGHT...WITH A DEFINITE NORTHWARD SHIFT OBSERVED IN THE LATEST
00Z/30 MODEL ITERATION. THIS RESULTS IN A SLIGHTLY SLOWER/DELAYED
ONSET OF PRECIP ACROSS THE AREA LATE SUNDAY AFTERNOON AND
EVENING...BUT IMPORTANTLY DISPLACES THE HEAVIER QPF NORTH OF THE
AREA.
AS SUCH...SUNDAY WILL END UP MOSTLY DRY ACROSS CENTRAL NC WITH
THICKENING CLOUD COVER THROUGH THE AFTERNOON WITH HIGHS RANGING FROM
MID 40S NORTH TO LOWER 50S SOUTH. RAIN CHANCES WILL QUICKLY RAMP UP
SUNDAY EVENING...WITH CATEGORICAL POPS SUNDAY NIGHT...CUTTING OFF
FROM WEST TO EAST MORNING MONDAY AS THE MID-LEVEL DRY SLOT RACES
EASTWARD. ESTIMATED QPF AMOUNTS NOW LOOK TO BE IN THE 0.25-0.50"
RANGE. WITH ONLY WEAK ELEVATED INSTABILITY AT BEST EXPECTED ACROSS
THE COASTAL PLAIN AND WITH THE SURFACE LOW NOW DISPLACED NORTH OF
THE AREA...WILL KEEP OUT THE MENTION OF ANY THUNDER ACROSS THE
EASTERN ZONES.
EXPECT A NON-DIURNAL TEMP TREND SUNDAY NIGHT...WITH LOWS OCCURRING
BEFORE MIDNIGHT...THEN TEMPERATURES WARMING OVERNIGHT OWING TO
STRONG WAA. LOWS SUNDAY NIGHT IN THE LOWER 40S NORTHWEST TO UPPER
40S SOUTHEAST. -CBL
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...
MONDAY THROUGH TUESDAY: AGGRESSIVE MID-LEVEL DRY AIR INTRUSION WILL
OVERTAKE THE AREA FROM THE WEST BETWEEN 12 TO 18Z MONDAY IN ADVANCE
OF THE PASSAGE OF THE NORTHERN STREAM TROUGH PASSAGE MONDAY
AFTERNOON. THIS WILL BRING AN ABRUPT END TO PRECIP ACROSS THE AREA
MONDAY MORNING...WITH RAIN/SHOWERS EXITING THE COASTAL PLAIN BY MID
TO LATE MORNING. EQUALLY IMPRESSIVE WILL BE STRONG POST-FRONTAL DRY
COLD AIR ADVECTION REGIME...WITH TEMPERATURES FALLING BY THE
AFTERNOON AS CONTINENTAL POLAR HIGH PRESSURE BUILDS INTO THE AREA
MONDAY NIGHT AND INTO THE DAY ON TUESDAY. IF PROJECTED LOW-LEVEL
THICKNESSES VERIFY AND WE DECOUPLE AS THE SURFACE HIGH MOVES
OVERHEAD... EXPECT LOWS TUESDAY MORNING IN THE UPPER TEENS TO LOWER
20S. UNDER FULL COMPLIMENTS OF SUN...TEMPS TUESDAY WILL STRUGGLE TO
WARM THROUGH THE 30S. HIGHS RANGING FROM MID/UPPER 30S NORTH TO
LOWER 40S SOUTH.
WEDNESDAY THROUGH THURSDAY: MODEL SPREAD REMAINS HIGH WITH THE
EVOLUTION OF THE SLOW MOVING UPPER LOW/TROUGH EJECTING EASTWARD FROM
MEXICO AND SUBSEQUENT DEVELOPMENT OF A LOW PRESSURE AREA TRACKING
ALONG THE SOUTHEAST COAST. IN A COMPLETE ROLE REVERSAL... THE GFS IS
NOW MORE PROGRESSIVE THAN THE EC WITH BRINGING PRECIP BACK INTO THE
AREA DURING THE DAY ON WEDNESDAY...WITH THE EC NEARLY 24 HOURS
SLOWER...DELAYING UNTIL THURSDAY. GIVEN LATER TIMING OF ONSET OF
PRECIP...LOW-LEVEL THICKNESSES CURRENTLY SUPPORT ALL RAIN. HOWEVER
IF FUTURE MODEL RUNS SPEED UP THE TIMING OF THE SYSTEM...ANY PRECIP
INTO THE AREA TUESDAY NIGHT/EARLY WEDNESDAY MORNING COULD BE OF THE
FROZEN VARIETY. WILL CONTINUE TO MONITOR TRENDS...BUT FOR NOW GIVEN
UNCERTAINTY WILL KEEP POPS AT SMALL CHANCE FOR WEDNESDAY AND
THURSDAY WITH A CONTINUATION OF BELOW NORMAL TEMPERATURES.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 635 AM FRIDAY...
VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE 12Z VALID TAF
PERIOD. A COLD FRONT MOVES THROUGH CENTRAL NORTH CAROLINA THIS
MORNING WHICH WILL RESULT IN RAPIDLY VEERING WINDS TO THE NORTHWEST
WITH SPEEDS INCREASING TO GUSTS AROUND 30KT BY LATE MORNING.
ALREADY...THE WIND HAD GUSTED TO 26KT AT KINT. WHILE THE GFS MODEL
SHOWS THE POTENTIAL FOR WIND GUSTS A LITTLE ABOVE THAT...THE NAM AND
RAP MODELS ARE LESS...AND MOMENTUM TRANSFER SPEEDS TOP OUT AT MOST
ABOUT 30KT ON ALL THREE WHICH WILL BE THE CAP FOR THE CENTRAL NORTH
CAROLINA TAFS. SHOWERS WERE MOVING AWAY FROM THE COASTAL PLAIN AND...
EXCEPT FOR KRWI INITIALLY...THE TAFS SHOW A DRY FORECAST.
WITH A STRONG MID-LEVEL DISTURBANCE MOVING THROUGH TODAY...THERE IS
THE POTENTIAL FOR SHALLOW CONVECTION...BROKEN VFR CLOUDS AND MAYBE A
LITTLE VIRGA KRDU AND EAST EARLY THIS AFTERNOON. WINDS DIMINISH THIS
EVENING DIURNALLY. HOWEVER...AVIATION INTERESTS SHOULD EXPECT
NORTHWEST WINDS AOA 30KT AT AND ABOVE 2000FT.
BEYOND THE 12Z VALID TAF PERIOD...VFR CONDITIONS CONTINUE INTO
SUNDAY...WITH AREAS OF HIGH CLOUDS MOVING IN SATURDAY NIGHT
GRADUALLY LOWERING SUNDAY. A CHANCE OF RAIN IN THE WESTERN PIEDMONT
SUNDAY AFTERNOON FOLLOWED BY BETTER CHANCES BY SUNDAY NIGHT ALONG
WITH THE POTENTIAL OF SUB-VFR CONDITIONS INTO MONDAY MORNING. VFR
CONDITIONS ARE EXPECTED TO RETURN BY MONDAY AFTERNOON ACCOMPANIED BY
BREEZY CONDITIONS ONCE AGAIN...WITH THE VFR CONDITIONS THEN
CONTINUING THROUGH TUESDAY.
&&
.FIRE WEATHER...
AS OF 300 AM FRIDAY...
WIND GUSTS TO 30KT TODAY...OR TO AROUND 35 MPH...ARE CERTAINLY
POSSIBLE AS THE SURFACE GRADIENT TIGHTENS BEHIND THE COLD FRONT.
SURFACE DEW POINTS WILL FALL BEHIND THE FRONT AS WELL...WITH THE
LOWEST GUIDANCE OF THE RAP SUGGESTING SOME DEW POINTS IN SINGLE
FIGURES LATE IN THE DAY IN THE NORTHWEST PIEDMONT. THE GFS IS
HIGHER...AND THE NAM IS MORE OF A COMPROMISE...WHICH IS CONSISTENT
WITH THE MOS GUIDANCE. BY 00Z SATURDAY...THE GRIDDED FORECAST WILL
SHOW A DEW POINT NEAR 10F IN THE TRIAD...BUT EVEN THERE THE MINIMUM
RELATIVE HUMIDITY IS IN THE UPPER 20S PERCENT. BASED THOSE DEW
POINTS...RECENT RAIN...AND EARLIER FORECAST SERVICE COORDINATION...
WILL FOR NOW HIGHLIGHT THE ADVERSE CONDITIONS OF THE WIND GUSTS IN
THE DISCUSSION OF THE FIRE WEATHER FORECAST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF/BLS
SHORT TERM...DJF/CBL
LONG TERM...CBL
AVIATION...DJF
FIRE WEATHER...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
636 AM EST FRI JAN 30 2015
.SYNOPSIS...FOLLOWING A COLD FRONT MOVING THROUGH CENTRAL NORTH
CAROLINA THIS MORNING AND OFFSHORE BY AFTERNOON...HIGH PRESSURE
BUILDS OVER THE REGION FROM THE NORTHWEST. THE HIGH MOVES OFFSHORE
SATURDAY NIGHT INTO SUNDAY. A LOW PRESSURE SYSTEM SHOULD MOVE INTO
THE REGION BY SUNDAY NIGHT.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 300 AM FRIDAY...
A COLD FRONT WAS SLOWLY MOVING ACROSS THE STATE EARLY THIS
MORNING...AND ALL OF THE GUIDANCE SUGGESTS STEADY PROGRESS WITH THE
FRONT AS IT MOVES THROUGH CENTRAL NORTH CAROLINA THIS MORNING AND
OFFSHORE BY EARLY AFTERNOON. JUST BEHIND THE FRONT...WATER VAPOR
IMAGERY SHOWS A GOOD DRY PUNCH MOVING ACROSS THE NORTH CAROLINA
MOUNTAINS...AS AN UPPER TROUGH EXTENDING FROM HUDSON BAY THROUGH THE
GREAT LAKES AND INTO THE OHIO VALLEY MOVES EAST. THIS MORNING...THE
NEAR-TERM GUIDANCE VARIES ON THE POTENTIAL FOR RENEWED PRECIPITATION
ACCOMPANYING THE FRONT AND THE LEFT-ENTRANCE REGION OF A 130KT 250MB
JET THAT WILL BE OVER OR NEAR SOUTHERN PARTS OF CENTRAL NORTH
CAROLINA THIS MORNING INTO THE AFTERNOON. BEHIND THE FRONT...850MB
THETA-E VALUES FALL SHARPLY AND K INDICES GO NEGATIVE...BUT WITH THE
FRONT THERE IS WEAK SPEED CONVERGENCE ON THE 295K SURFACE OF THE GFS
ESPECIALLY TOWARD THE SANDHILLS AND SOUTHERN COASTAL PLAIN. AS OF
THIS WRITING A FEW...FAINT ECHOES WERE NOTED ON THE KRAX WSR-88D
JUST EAST OF KGSO TOWARD KBUY...BUT BETTER SURFACE DEW POINTS WERE
OFF TO THE EAST AND SOUTHEAST TOWARD KETC...KFAY...AND KCTZ. PLAN TO
AT LEAST HAVE A SLIGHT CHANCE OF EARLY MORNING SHOWERS MAINLY ALONG
AND EAST OF ABOUT U.S. 1...WITH A CHANCE IN SOME LOCATIONS TOWARD
INTERSTATE 95 WHERE THE LOW-LEVEL MOISTURE WILL BE GREATER AS THE
FRONT MOVES THROUGH WITH THE UPPER SUPPORT.
SKIES SHOULD START TO CLEAR IN GENERAL BEHIND THE FRONT...THOUGH THE
NAM AND GFS BUFR SOUNDINGS ESPECIALLY FROM THE TRIANGLE NORTH AND
EAST SUGGEST A PERIOD OF BROKEN STRATOCU OR SHALLOW CU DURING THE
EARLY TO MID AFTERNOON AS THE TROUGH AXIS AND MODERATE VORTICITY
MOVE THROUGH CENTRAL NORTH CAROLINA. IN FACT...THE GFS BUFR
SOUNDINGS NEAR KRDU IN PARTICULAR WOULD SUGGEST ENOUGH LIFT...ALBEIT
SHALLOW...TO GET A PARCEL A LITTLE COLDER THAN -10C AND POSSIBLY
PROVIDE FOR VIRGA OR A SPRINKLE. WILL LEAVE THE AFTERNOON FORECAST
DRY...THOUGH SHOW A PERIOD OF GREATER CLOUD COVER FROM THE TRIANGLE
NORTH AND EAST DURING A PART OF THE AFTERNOON.
IN ADDITION...THE SURFACE GRADIENT TIGHTENS BEHIND THE FRONT WITH
850MB WINDS OF 30 TO 35KT AND 925MB WINDS DIMINISHING FROM NEAR 40KT
EARLY THIS MORNING TO AROUND 30KT BY 18Z. PURE LIFT FROM THE GFS
BUFR SOUNDINGS UP THE DRY ADIABAT WOULD SUGGEST WIND GUSTS ABOVE
30KT POSSIBLE...BUT THE NAM AND RAP SOUNDINGS SUGGEST A LITTLE LOWER
GUSTS AND MOMENTUM TRANSFER FIELDS FROM ALL THREE MODELS ON BUFKIT
CAP GUSTS AT 30KT. WILL KEEP THE GUSTS TO 30KT OR 35MPH IN THE
FORECAST WHILE ANTICIPATING A SPOT OR THREE TO BE BRIEFLY A LITTLE
ABOVE THAT. THICKNESSES IN MANY PARTS OF CENTRAL NORTH CAROLINA FALL
DURING THE DAY...AND 1000-850MB THICKNESSES WOULD SUGGEST A LEAN
TOWARD THE SLIGHTLY COOLER MET MOS FOR HIGHS TODAY. BASED ON CURRENT
READINGS AND EXPECTED SUN OFFSET BY COOL ADVECTION...WILL HAVE HIGHS
FROM THE MID 40S TO AROUND 50 AND SHADING TOWARD THE MET MOS.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...
WINDS WILL DIMINISH TONIGHT UNDER CLEAR SKIES. THERE SHOULD BE
ENOUGH OF A GRADIENT FOR AT LEAST A SLIGHT STIR TO THE WIND THROUGH
THE NIGHT...AS 925MB WINDS REMAIN TO 35KT. SURFACE DEW POINTS SHOULD
CONTINUE TO DRY...AND 1000-850MB THICKNESSES WOULD SUGGEST LOWS FROM
THE TEENS TO THE LOWER 20S. THIS WILL ESSENTIALLY BE THE FORECAST
FOR LOWS OVERNIGHT...19 TO 20 IN THE NORTHWEST PIEDMONT TO NEAR 25
TOWARD KFAY...CLOSE TO THE AVERAGE OF THE MET AND MAV MOS. ON
SATURDAY...925MB WINDS DIMINISH TO AROUND 15KT BY 18Z...AND BUFR
SOUNDINGS FROM BOTH THE NAM AND GFS SUGGEST A FEW WIND GUSTS IN THE
TEENS KNOTS WITH INITIAL MIXING BEFORE THE WINDS DIMINISH AS HIGH
PRESSURE CONTINUES TO BUILD IN FROM THE NORTHWEST.
SATURDAY AFTERNOON...A FLAT RIDGE AXIS ALOFT GETS CLOSE TO CENTRAL
NORTH CAROLINA AS SOME MID-LEVEL VORTICITY ADVECTION MOVES INTO AND
ACROSS CENTRAL NORTH CAROLINA DURING THE LATE AFTERNOON AND
NIGHTTIME HOURS...FORECAST BY BOTH THE GFS AND NAM. GFS AND NAM BUFR
SOUNDINGS SUGGEST INCREASING UPPER-LEVEL MOISTURE SUCH THAT
INCREASING HIGH CLOUDS SHOULD GRADUALLY OCCUR FROM SATURDAY
AFTERNOON INTO SATURDAY NIGHT. WITH MOST IF NOT ALL OF CENTRAL NORTH
CAROLINA EXPECTED TO BE MOSTLY CLOUDY BY THE MIDDLE OF THE NIGHT
SATURDAY...OVERNIGHT LOWS SHOULD BE WARMER...MID TO UPPER 20S IN THE
NORTHERN COASTAL PLAIN TO AROUND 30 ELSEWHERE. -DJF
MINOR MID-LEVEL IMPULSES EMANATING FROM THE UPPER TROUGH/CLOSED LOW
OVER THE SOUTHWEST US WILL GET KICKED EASTWARD...IN ADVANCE OF AN
AMPLIFYING NORTHERN STREAM OVER THE CENTRAL PLAINS...ON SUNDAY.
ASSOCIATED CYCLOGENESIS WILL TRACK EASTWARD ACROSS THE LOWER MS
VALLEY/TN VALLEY ON SUNDAY...THEN ACROSS THE CAROLINAS/VIRGINIA
SUNDAY NIGHT BEFORE MOVING OFF THE MID-ATLANTIC COAST MONDAY
MORNING.
NWP MODEL GUIDANCE CONTINUES TO EXHIBIT CONSIDERABLE SPREAD WITH THE
TRACK OF THE SURFACE LOW AS IT MOVES THROUGH THE REGION SUNDAY
NIGHT...WITH A DEFINITE NORTHWARD SHIFT OBSERVED IN THE LATEST
00Z/30 MODEL ITERATION. THIS RESULTS IN A SLIGHTLY SLOWER/DELAYED
ONSET OF PRECIP ACROSS THE AREA LATE SUNDAY AFTERNOON AND
EVENING...BUT IMPORTANTLY DISPLACES THE HEAVIER QPF NORTH OF THE
AREA.
AS SUCH...SUNDAY WILL END UP MOSTLY DRY ACROSS CENTRAL NC WITH
THICKENING CLOUD COVER THROUGH THE AFTERNOON WITH HIGHS RANGING FROM
MID 40S NORTH TO LOWER 50S SOUTH. RAIN CHANCES WILL QUICKLY RAMP UP
SUNDAY EVENING...WITH CATEGORICAL POPS SUNDAY NIGHT...CUTTING OFF
FROM WEST TO EAST MORNING MONDAY AS THE MID-LEVEL DRY SLOT RACES
EASTWARD. ESTIMATED QPF AMOUNTS NOW LOOK TO BE IN THE 0.25-0.50"
RANGE. WITH ONLY WEAK ELEVATED INSTABILITY AT BEST EXPECTED ACROSS
THE COASTAL PLAIN AND WITH THE SURFACE LOW NOW DISPLACED NORTH OF
THE AREA...WILL KEEP OUT THE MENTION OF ANY THUNDER ACROSS THE
EASTERN ZONES.
EXPECT A NON-DIURNAL TEMP TREND SUNDAY NIGHT...WITH LOWS OCCURRING
BEFORE MIDNIGHT...THEN TEMPERATURES WARMING OVERNIGHT OWING TO
STRONG WAA. LOWS SUNDAY NIGHT IN THE LOWER 40S NORTHWEST TO UPPER
40S SOUTHEAST. -CBL
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...
MONDAY THROUGH TUESDAY: AGGRESSIVE MID-LEVEL DRY AIR INTRUSION WILL
OVERTAKE THE AREA FROM THE WEST BETWEEN 12 TO 18Z MONDAY IN ADVANCE
OF THE PASSAGE OF THE NORTHERN STREAM TROUGH PASSAGE MONDAY
AFTERNOON. THIS WILL BRING AN ABRUPT END TO PRECIP ACROSS THE AREA
MONDAY MORNING...WITH RAIN/SHOWERS EXITING THE COASTAL PLAIN BY MID
TO LATE MORNING. EQUALLY IMPRESSIVE WILL BE STRONG POST-FRONTAL DRY
COLD AIR ADVECTION REGIME...WITH TEMPERATURES FALLING BY THE
AFTERNOON AS CONTINENTAL POLAR HIGH PRESSURE BUILDS INTO THE AREA
MONDAY NIGHT AND INTO THE DAY ON TUESDAY. IF PROJECTED LOW-LEVEL
THICKNESSES VERIFY AND WE DECOUPLE AS THE SURFACE HIGH MOVES
OVERHEAD... EXPECT LOWS TUESDAY MORNING IN THE UPPER TEENS TO LOWER
20S. UNDER FULL COMPLIMENTS OF SUN...TEMPS TUESDAY WILL STRUGGLE TO
WARM THROUGH THE 30S. HIGHS RANGING FROM MID/UPPER 30S NORTH TO
LOWER 40S SOUTH.
WEDNESDAY THROUGH THURSDAY: MODEL SPREAD REMAINS HIGH WITH THE
EVOLUTION OF THE SLOW MOVING UPPER LOW/TROUGH EJECTING EASTWARD FROM
MEXICO AND SUBSEQUENT DEVELOPMENT OF A LOW PRESSURE AREA TRACKING
ALONG THE SOUTHEAST COAST. IN A COMPLETE ROLE REVERSAL... THE GFS IS
NOW MORE PROGRESSIVE THAN THE EC WITH BRINGING PRECIP BACK INTO THE
AREA DURING THE DAY ON WEDNESDAY...WITH THE EC NEARLY 24 HOURS
SLOWER...DELAYING UNTIL THURSDAY. GIVEN LATER TIMING OF ONSET OF
PRECIP...LOW-LEVEL THICKNESSES CURRENTLY SUPPORT ALL RAIN. HOWEVER
IF FUTURE MODEL RUNS SPEED UP THE TIMING OF THE SYSTEM...ANY PRECIP
INTO THE AREA TUESDAY NIGHT/EARLY WEDNESDAY MORNING COULD BE OF THE
FROZEN VARIETY. WILL CONTINUE TO MONITOR TRENDS...BUT FOR NOW GIVEN
UNCERTAINTY WILL KEEP POPS AT SMALL CHANCE FOR WEDNESDAY AND
THURSDAY WITH A CONTINUATION OF BELOW NORMAL TEMPERATURES.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 635 AM FRIDAY...
VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE 12Z VALID TAF
PERIOD. A COLD FRONT MOVES THROUGH CENTRAL NORTH CAROLINA THIS
MORNING WHICH WILL RESULT IN RAPIDLY VEERING WINDS TO THE NORTHWEST
WITH SPEEDS INCREASING TO GUSTS AROUND 30KT BY LATE MORNING.
ALREADY...THE WIND HAD GUSTED TO 26KT AT KINT. WHILE THE GFS MODEL
SHOWS THE POTENTIAL FOR WIND GUSTS A LITTLE ABOVE THAT...THE NAM AND
RAP MODELS ARE LESS...AND MOMENTUM TRANSFER SPEEDS TOP OUT AT MOST
ABOUT 30KT ON ALL THREE WHICH WILL BE THE CAP FOR THE CENTRAL NORTH
CAROLINA TAFS. SHOWERS WERE MOVING AWAY FROM THE COASTAL PLAIN AND...
EXCEPT FOR KRWI INITIALLY...THE TAFS SHOW A DRY FORECAST.
WITH A STRONG MID-LEVEL DISTURBANCE MOVING THROUGH TODAY...THERE IS
THE POTENTIAL FOR SHALLOW CONVECTION...BROKEN VFR CLOUDS AND MAYBE A
LITTLE VIRGA KRDU AND EAST EARLY THIS AFTERNOON. WINDS DIMINISH THIS
EVENING DIURNALLY. HOWEVER...AVIATION INTERESTS SHOULD EXPECT
NORTHWEST WINDS AOA 30KT AT AND ABOVE 2000FT.
BEYOND THE 12Z VALID TAF PERIOD...VFR CONDITIONS CONTINUE INTO
SUNDAY...WITH AREAS OF HIGH CLOUDS MOVING IN SATURDAY NIGHT
GRADUALLY LOWERING SUNDAY. A CHANCE OF RAIN IN THE WESTERN PIEDMONT
SUNDAY AFTERNOON FOLLOWED BY BETTER CHANCES BY SUNDAY NIGHT ALONG
WITH THE POTENTIAL OF SUB-VFR CONDITIONS INTO MONDAY MORNING. VFR
CONDITIONS ARE EXPECTED TO RETURN BY MONDAY AFTERNOON ACCOMPANIED BY
BREEZY CONDITIONS ONCE AGAIN...WITH THE VFR CONDITIONS THEN
CONTINUING THROUGH TUESDAY.
&&
.FIRE WEATHER...
AS OF 300 AM FRIDAY...
WIND GUSTS TO 30KT TODAY...OR TO AROUND 35 MPH...ARE CERTAINLY
POSSIBLE AS THE SURFACE GRADIENT TIGHTENS BEHIND THE COLD FRONT.
SURFACE DEW POINTS WILL FALL BEHIND THE FRONT AS WELL...WITH THE
LOWEST GUIDANCE OF THE RAP SUGGESTING SOME DEW POINTS IN SINGLE
FIGURES LATE IN THE DAY IN THE NORTHWEST PIEDMONT. THE GFS IS
HIGHER...AND THE NAM IS MORE OF A COMPROMISE...WHICH IS CONSISTENT
WITH THE MOS GUIDANCE. BY 00Z SATURDAY...THE GRIDDED FORECAST WILL
SHOW A DEW POINT NEAR 10F IN THE TRIAD...BUT EVEN THERE THE MINIMUM
RELATIVE HUMIDITY IS IN THE UPPER 20S PERCENT. BASED THOSE DEW
POINTS...RECENT RAIN...AND EARLIER FORECAST SERVICE COORDINATION...
WILL FOR NOW HIGHLIGHT THE ADVERSE CONDITIONS OF THE WIND GUSTS IN
THE DISCUSSION OF THE FIRE WEATHER FORECAST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...DJF/CBL
LONG TERM...CBL
AVIATION...DJF
FIRE WEATHER...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
301 AM EST FRI JAN 30 2015
.SYNOPSIS...FOLLOWING A COLD FRONT MOVING THROUGH CENTRAL NORTH
CAROLINA THIS MORNING AND OFFSHORE BY AFTERNOON...HIGH PRESSURE
BUILDS OVER THE REGION FROM THE NORTHWEST. THE HIGH MOVES OFFSHORE
SATURDAY NIGHT INTO SUNDAY. A LOW PRESSURE SYSTEM SHOULD MOVE INTO
THE REGION BY SUNDAY NIGHT.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 300 AM FRIDAY...
A COLD FRONT WAS SLOWLY MOVING ACROSS THE STATE EARLY THIS
MORNING...AND ALL OF THE GUIDANCE SUGGESTS STEADY PROGRESS WITH THE
FRONT AS IT MOVES THROUGH CENTRAL NORTH CAROLINA THIS MORNING AND
OFFSHORE BY EARLY AFTERNOON. JUST BEHIND THE FRONT...WATER VAPOR
IMAGERY SHOWS A GOOD DRY PUNCH MOVING ACROSS THE NORTH CAROLINA
MOUNTAINS...AS AN UPPER TROUGH EXTENDING FROM HUDSON BAY THROUGH THE
GREAT LAKES AND INTO THE OHIO VALLEY MOVES EAST. THIS MORNING...THE
NEAR-TERM GUIDANCE VARIES ON THE POTENTIAL FOR RENEWED PRECIPITATION
ACCOMPANYING THE FRONT AND THE LEFT-ENTRANCE REGION OF A 130KT 250MB
JET THAT WILL BE OVER OR NEAR SOUTHERN PARTS OF CENTRAL NORTH
CAROLINA THIS MORNING INTO THE AFTERNOON. BEHIND THE FRONT...850MB
THETA-E VALUES FALL SHARPLY AND K INDICES GO NEGATIVE...BUT WITH THE
FRONT THERE IS WEAK SPEED CONVERGENCE ON THE 295K SURFACE OF THE GFS
ESPECIALLY TOWARD THE SANDHILLS AND SOUTHERN COASTAL PLAIN. AS OF
THIS WRITING A FEW...FAINT ECHOES WERE NOTED ON THE KRAX WSR-88D
JUST EAST OF KGSO TOWARD KBUY...BUT BETTER SURFACE DEW POINTS WERE
OFF TO THE EAST AND SOUTHEAST TOWARD KETC...KFAY...AND KCTZ. PLAN TO
AT LEAST HAVE A SLIGHT CHANCE OF EARLY MORNING SHOWERS MAINLY ALONG
AND EAST OF ABOUT U.S. 1...WITH A CHANCE IN SOME LOCATIONS TOWARD
INTERSTATE 95 WHERE THE LOW-LEVEL MOISTURE WILL BE GREATER AS THE
FRONT MOVES THROUGH WITH THE UPPER SUPPORT.
SKIES SHOULD START TO CLEAR IN GENERAL BEHIND THE FRONT...THOUGH THE
NAM AND GFS BUFR SOUNDINGS ESPECIALLY FROM THE TRIANGLE NORTH AND
EAST SUGGEST A PERIOD OF BROKEN STRATOCU OR SHALLOW CU DURING THE
EARLY TO MID AFTERNOON AS THE TROUGH AXIS AND MODERATE VORTICITY
MOVE THROUGH CENTRAL NORTH CAROLINA. IN FACT...THE GFS BUFR
SOUNDINGS NEAR KRDU IN PARTICULAR WOULD SUGGEST ENOUGH LIFT...ALBEIT
SHALLOW...TO GET A PARCEL A LITTLE COLDER THAN -10C AND POSSIBLY
PROVIDE FOR VIRGA OR A SPRINKLE. WILL LEAVE THE AFTERNOON FORECAST
DRY...THOUGH SHOW A PERIOD OF GREATER CLOUD COVER FROM THE TRIANGLE
NORTH AND EAST DURING A PART OF THE AFTERNOON.
IN ADDITION...THE SURFACE GRADIENT TIGHTENS BEHIND THE FRONT WITH
850MB WINDS OF 30 TO 35KT AND 925MB WINDS DIMINISHING FROM NEAR 40KT
EARLY THIS MORNING TO AROUND 30KT BY 18Z. PURE LIFT FROM THE GFS
BUFR SOUNDINGS UP THE DRY ADIABAT WOULD SUGGEST WIND GUSTS ABOVE
30KT POSSIBLE...BUT THE NAM AND RAP SOUNDINGS SUGGEST A LITTLE LOWER
GUSTS AND MOMENTUM TRANSFER FIELDS FROM ALL THREE MODELS ON BUFKIT
CAP GUSTS AT 30KT. WILL KEEP THE GUSTS TO 30KT OR 35MPH IN THE
FORECAST WHILE ANTICIPATING A SPOT OR THREE TO BE BRIEFLY A LITTLE
ABOVE THAT. THICKNESSES IN MANY PARTS OF CENTRAL NORTH CAROLINA FALL
DURING THE DAY...AND 1000-850MB THICKNESSES WOULD SUGGEST A LEAN
TOWARD THE SLIGHTLY COOLER MET MOS FOR HIGHS TODAY. BASED ON CURRENT
READINGS AND EXPECTED SUN OFFSET BY COOL ADVECTION...WILL HAVE HIGHS
FROM THE MID 40S TO AROUND 50 AND SHADING TOWARD THE MET MOS.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...
WINDS WILL DIMINISH TONIGHT UNDER CLEAR SKIES. THERE SHOULD BE
ENOUGH OF A GRADIENT FOR AT LEAST A SLIGHT STIR TO THE WIND THROUGH
THE NIGHT...AS 925MB WINDS REMAIN TO 35KT. SURFACE DEW POINTS SHOULD
CONTINUE TO DRY...AND 1000-850MB THICKNESSES WOULD SUGGEST LOWS FROM
THE TEENS TO THE LOWER 20S. THIS WILL ESSENTIALLY BE THE FORECAST
FOR LOWS OVERNIGHT...19 TO 20 IN THE NORTHWEST PIEDMONT TO NEAR 25
TOWARD KFAY...CLOSE TO THE AVERAGE OF THE MET AND MAV MOS. ON
SATURDAY...925MB WINDS DIMINISH TO AROUND 15KT BY 18Z...AND BUFR
SOUNDINGS FROM BOTH THE NAM AND GFS SUGGEST A FEW WIND GUSTS IN THE
TEENS KNOTS WITH INITIAL MIXING BEFORE THE WINDS DIMINISH AS HIGH
PRESSURE CONTINUES TO BUILD IN FROM THE NORTHWEST.
SATURDAY AFTERNOON...A FLAT RIDGE AXIS ALOFT GETS CLOSE TO CENTRAL
NORTH CAROLINA AS SOME MID-LEVEL VORTICITY ADVECTION MOVES INTO AND
ACROSS CENTRAL NORTH CAROLINA DURING THE LATE AFTERNOON AND
NIGHTTIME HOURS...FORECAST BY BOTH THE GFS AND NAM. GFS AND NAM BUFR
SOUNDINGS SUGGEST INCREASING UPPER-LEVEL MOISTURE SUCH THAT
INCREASING HIGH CLOUDS SHOULD GRADUALLY OCCUR FROM SATURDAY
AFTERNOON INTO SATURDAY NIGHT. WITH MOST IF NOT ALL OF CENTRAL NORTH
CAROLINA EXPECTED TO BE MOSTLY CLOUDY BY THE MIDDLE OF THE NIGHT
SATURDAY...OVERNIGHT LOWS SHOULD BE WARMER...MID TO UPPER 20S IN THE
NORTHERN COASTAL PLAIN TO AROUND 30 ELSEWHERE. -DJF
MINOR MID-LEVEL IMPULSES EMANATING FROM THE UPPER TROUGH/CLOSED LOW
OVER THE SOUTHWEST US WILL GET KICKED EASTWARD...IN ADVANCE OF AN
AMPLIFYING NORTHERN STREAM OVER THE CENTRAL PLAINS...ON SUNDAY.
ASSOCIATED CYCLOGENESIS WILL TRACK EASTWARD ACROSS THE LOWER MS
VALLEY/TN VALLEY ON SUNDAY...THEN ACROSS THE CAROLINAS/VIRGINIA
SUNDAY NIGHT BEFORE MOVING OFF THE MID-ATLANTIC COAST MONDAY
MORNING.
NWP MODEL GUIDANCE CONTINUES TO EXHIBIT CONSIDERABLE SPREAD WITH THE
TRACK OF THE SURFACE LOW AS IT MOVES THROUGH THE REGION SUNDAY
NIGHT...WITH A DEFINITE NORTHWARD SHIFT OBSERVED IN THE LATEST
00Z/30 MODEL ITERATION. THIS RESULTS IN A SLIGHTLY SLOWER/DELAYED
ONSET OF PRECIP ACROSS THE AREA LATE SUNDAY AFTERNOON AND
EVENING...BUT IMPORTANTLY DISPLACES THE HEAVIER QPF NORTH OF THE
AREA.
AS SUCH...SUNDAY WILL END UP MOSTLY DRY ACROSS CENTRAL NC WITH
THICKENING CLOUD COVER THROUGH THE AFTERNOON WITH HIGHS RANGING FROM
MID 40S NORTH TO LOWER 50S SOUTH. RAIN CHANCES WILL QUICKLY RAMP UP
SUNDAY EVENING...WITH CATEGORICAL POPS SUNDAY NIGHT...CUTTING OFF
FROM WEST TO EAST MORNING MONDAY AS THE MID-LEVEL DRY SLOT RACES
EASTWARD. ESTIMATED QPF AMOUNTS NOW LOOK TO BE IN THE 0.25-0.50"
RANGE. WITH ONLY WEAK ELEVATED INSTABILITY AT BEST EXPECTED ACROSS
THE COASTAL PLAIN AND WITH THE SURFACE LOW NOW DISPLACED NORTH OF
THE AREA...WILL KEEP OUT THE MENTION OF ANY THUNDER ACROSS THE
EASTERN ZONES.
EXPECT A NON-DIURNAL TEMP TREND SUNDAY NIGHT...WITH LOWS OCCURRING
BEFORE MIDNIGHT...THEN TEMPERATURES WARMING OVERNIGHT OWING TO
STRONG WAA. LOWS SUNDAY NIGHT IN THE LOWER 40S NORTHWEST TO UPPER
40S SOUTHEAST. -CBL
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...
MONDAY THROUGH TUESDAY: AGGRESSIVE MID-LEVEL DRY AIR INTRUSION WILL
OVERTAKE THE AREA FROM THE WEST BETWEEN 12 TO 18Z MONDAY IN ADVANCE
OF THE PASSAGE OF THE NORTHERN STREAM TROUGH PASSAGE MONDAY
AFTERNOON. THIS WILL BRING AN ABRUPT END TO PRECIP ACROSS THE AREA
MONDAY MORNING...WITH RAIN/SHOWERS EXITING THE COASTAL PLAIN BY MID
TO LATE MORNING. EQUALLY IMPRESSIVE WILL BE STRONG POST-FRONTAL DRY
COLD AIR ADVECTION REGIME...WITH TEMPERATURES FALLING BY THE
AFTERNOON AS CONTINENTAL POLAR HIGH PRESSURE BUILDS INTO THE AREA
MONDAY NIGHT AND INTO THE DAY ON TUESDAY. IF PROJECTED LOW-LEVEL
THICKNESSES VERIFY AND WE DECOUPLE AS THE SURFACE HIGH MOVES
OVERHEAD... EXPECT LOWS TUESDAY MORNING IN THE UPPER TEENS TO LOWER
20S. UNDER FULL COMPLIMENTS OF SUN...TEMPS TUESDAY WILL STRUGGLE TO
WARM THROUGH THE 30S. HIGHS RANGING FROM MID/UPPER 30S NORTH TO
LOWER 40S SOUTH.
WEDNESDAY THROUGH THURSDAY: MODEL SPREAD REMAINS HIGH WITH THE
EVOLUTION OF THE SLOW MOVING UPPER LOW/TROUGH EJECTING EASTWARD FROM
MEXICO AND SUBSEQUENT DEVELOPMENT OF A LOW PRESSURE AREA TRACKING
ALONG THE SOUTHEAST COAST. IN A COMPLETE ROLE REVERSAL... THE GFS IS
NOW MORE PROGRESSIVE THAN THE EC WITH BRINGING PRECIP BACK INTO THE
AREA DURING THE DAY ON WEDNESDAY...WITH THE EC NEARLY 24 HOURS
SLOWER...DELAYING UNTIL THURSDAY. GIVEN LATER TIMING OF ONSET OF
PRECIP...LOW-LEVEL THICKNESSES CURRENTLY SUPPORT ALL RAIN. HOWEVER
IF FUTURE MODEL RUNS SPEED UP THE TIMING OF THE SYSTEM...ANY PRECIP
INTO THE AREA TUESDAY NIGHT/EARLY WEDNESDAY MORNING COULD BE OF THE
FROZEN VARIETY. WILL CONTINUE TO MONITOR TRENDS...BUT FOR NOW GIVEN
UNCERTAINTY WILL KEEP POPS AT SMALL CHANCE FOR WEDNESDAY AND
THURSDAY WITH A CONTINUATION OF BELOW NORMAL TEMPERATURES.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 1255 AM FRIDAY...
VFR CONDITIONS ARE EXPECTED OVERALL THROUGH THE 06Z VALID TAF
PERIOD. A COLD FRONT MOVES THROUGH CENTRAL NORTH CAROLINA THIS
MORNING WHICH WILL RESULT IN RAPIDLY VEERING WINDS TO THE NORTHWEST
WITH SPEEDS INCREASING TO GUSTS AROUND 30KT BY LATE MORNING. WHILE
THE GFS MODEL SHOWS THE POTENTIAL FOR WIND GUSTS A LITTLE ABOVE
THAT...THE NAM AND RAP MODELS ARE LESS...AND MOMENTUM TRANSFER
SPEEDS TOP OUT AT ABOUT 30KT ON ALL THREE WHICH WILL BE THE CAP FOR
THE CENTRAL NORTH CAROLINA TAFS. SOME OF THE CONVECTIVE-ALLOWING
MODELS SUGGEST A FEW SHOWERS WITH THE FRONT EARLY THIS MORNING
AROUND DAYBREAK NORTHEAST OF KRWI AND TOWARD KFAY...AND HAVE NOTED
VCSH IN THE TAF AT KFAY WHERE THE LOW-LEVEL MOISTURE IS GREATER THIS
EARLY MORNING. WITH A STRONG MID-LEVEL DISTURBANCE MOVING THROUGH
TODAY...THERE IS THE POTENTIAL FOR SHALLOW CONVECTION...BROKEN VFR
CLOUDS AND MAYBE A LITTLE VIRGA KRDU AND EAST EARLY THIS AFTERNOON.
WINDS DIMINISH THIS EVENING DIURNALLY THOUGH EXPECT NORTHWEST WINDS
AOA 30KT AT AND ABOVE 2000FT.
BEYOND THE 06Z VALID TAF PERIOD...VFR CONDITIONS CONTINUE INTO
SUNDAY...WITH AREAS OF HIGH CLOUDS MOVING IN SATURDAY NIGHT
GRADUALLY LOWERING SUNDAY. A CHANCE OF RAIN IN THE WESTERN PIEDMONT
SUNDAY AFTERNOON FOLLOWED BY BETTER CHANCES BY SUNDAY NIGHT ALONG
WITH THE POTENTIAL OF SUB-VFR CONDITIONS INTO MONDAY MORNING. VFR
CONDITIONS ARE EXPECTED TO RETURN BY MONDAY AFTERNOON ACCOMPANIED BY
BREEZY CONDITIONS ONCE AGAIN...WITH THE VFR CONDITIONS THEN
CONTINUING THROUGH TUESDAY.
&&
.FIRE WEATHER...
AS OF 300 AM FRIDAY...
WIND GUSTS TO 30KT TODAY...OR TO AROUND 35 MPH...ARE CERTAINLY
POSSIBLE AS THE SURFACE GRADIENT TIGHTENS BEHIND THE COLD FRONT.
SURFACE DEW POINTS WILL FALL BEHIND THE FRONT AS WELL...WITH THE
LOWEST GUIDANCE OF THE RAP SUGGESTING SOME DEW POINTS IN SINGLE
FIGURES LATE IN THE DAY IN THE NORTHWEST PIEDMONT. THE GFS IS
HIGHER...AND THE NAM IS MORE OF A COMPROMISE...WHICH IS CONSISTENT
WITH THE MOS GUIDANCE. BY 00Z SATURDAY...THE GRIDDED FORECAST WILL
SHOW A DEW POINT NEAR 10F IN THE TRIAD...BUT EVEN THERE THE MINIMUM
RELATIVE HUMIDITY IS IN THE UPPER 20S PERCENT. BASED THOSE DEW
POINTS...RECENT RAIN...AND EARLIER FORECAST SERVICE COORDINATION...
WILL FOR NOW HIGHLIGHT THE ADVERSE CONDITIONS OF THE WIND GUSTS IN
THE DISCUSSION OF THE FIRE WEATHER FORECAST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...DJF/CBL
LONG TERM...CBL
AVIATION...DJF
FIRE WEATHER...DJF
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
102 AM EST FRI JAN 30 2015
.SYNOPSIS...
A COLD FRONT WITH LIMITED MOISTURE WILL MOVE THROUGH THE AREA
LATE TONIGHT INTO FRIDAY MORNING. HIGH PRESSURE WILL BUILD OVER
THE AREA LATE FRIDAY INTO SUNDAY. ANOTHER FRONTAL SYSTEM WILL
AFFECT THE AREA SUNDAY NIGHT INTO MONDAY WITH HIGH PRESSURE
BUILDING INTO THE AREA TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1 AM FRIDAY...STRONG MID-LEVEL SHORTWAVE APPROACHING FROM
TENNESSEE AS A COLD FRONT WORKS IT WAY THROUGH THE MOUNTAINS. THIS
SYSTEM IS PRODUCING SOME LIGHT TO MODERATE SHOWERS NEAR THE COAST.
HAVE CONTINUE CHANCE POPS OVER BASICALLY THE SOUTHERN THIRD OF THE
CWA THROUGH THE EARLY MORNING HOURS...AS BOTH THE 3KM HRRR AND RAP
SHOWS RAIN CONTINUING OVERNIGHT.
TEMPERATURES HAVE RISEN OVER THE SOUTHERN HALF OF THE REGION WITH
WEAK WAA UNDERWAY AND HAVE TWEAKED TEMPERATURES UPWARD IN THESE
AREAS AS KHSE HAS RISEN TO 50 DEGREES WITH 54 DEGREES AT BEAUFORT.
MUCH COLDER WELL INLAND WITH 37 DEGREE AT KPGV. THE LIGHT
PRECIPITATION SHOULD BE IN THE WARMER AIR AND NO PRECIP TYPE
ISSUES EXPECTED OVERNIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
AS OF 300 PM THURSDAY...COLD FRONT WILL BE OFF COAST AT BEGINNING OF
PERIOD WITH LINGERING CHC OF SHOWERS FOR A FEW HOURS...THEN CLEARING
AND DRYING WITH STRONG CAA DEVELOPING MID MORNING THROUGH AFTN.
DOWNSLOPING NW WINDS AND FULL INSOLATION WILL OFFSET DECREASING LOW
LVL THICKNESSES...ALLOWING MAX TEMPS TO REACH MID-UPR 40S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
AS OF 330 PM THU...LONG TERM PERIOD WILL FEATURE A VERY CHANGEABLE
WEATHER PATTERN WITH BELOW NORMAL TEMPERATURES OVERALL.
FOR FRI NIGHT...CONTINUING CAA WILL BRING CHILLY AND BREEZY
CONDITIONS TO E NC. LOWS WILL DROP DOWN INTO THE LOWER 20 MOST
AREAS WITH SOME UPR 20S ON THE OBX. THE BRISK NW WIND WILL MAKE IT
FEEL IN THE TEENS.
FOR SAT...HIGH PRES WILL BUILD OVER THE AREA WITH SUNNY SKIES
THOUGH COOL BELOW NORMAL TEMPS. LOW LEVEL THICKNESS VALS SUGGEST
HIGHS IN THE LOW TO MID 40S...WITH SOME UPR 30S NORTHERN OBX.
WINDS WILL BECOME LIGHT AND BACK WSW BY LATE IN THE DAY. LOW TEMPS
SAT NIGHT WILL BE TRICKY...AS INC WAA ALOFT WILL BRING AN INC AND
THICKENING OF CLOUDS. LOWS MAY BE REALIZED PRIOR TO MIDNIGHT...
WITH READINGS IN THE UPR 20S LEVELING OFF OR RISING THEREAFTER.
FOR SUNDAY...EXPECT MOSTLY CLOUDY TO OVERCAST SKIES THOUGH DRY
CONDITIONS. THE CLOUDS DUE TO INC WAA ALOFT AS SW FLOW INC. AT THE
SFC...HIGH PRES WILL SLIDE EASTWARD TO THE SOUTH OF THE AREA.
ZONAL FLOW ALOFT WILL BRING NEAR SEASONAL TEMPS WITH LOW/MID 50S
SOUTH TO UPR 40S NORTHERN TIER.
MODELS CONVERGING ON TIMING OF FRONTAL BOUNDARY AND LOW PRES AREA
SET TO MOVE THROUGH THE REGION LATE SUNDAY INTO EARLY MONDAY. THE
29/12Z ECM/GFS BRING LOW PRES NEAR OR JUST NORTH OF THE VA/NC
BORDER SOMETIME LATE SUN NIGHT OR EARLY MON MORNING...WHILE THE
CMC BRINGS THE LOW OVER E NC. WILL SIDE WITH THE FURTHER NORTH
SOLN AND THEREFORE KEEP AREA IN MILD SW FLOW. NO PTYPE ISSUES AREA
EXPECTED SUN NIGHT WITH INCREASING RAIN CHANCES THROUGH THE NIGHT
AS FGEN/LARGE SCALE LIFT INCREASE THROUGH THE NIGHT. RAINFALL
AMOUNTS NOT EXPECTED TO BE TERRIBLY HIGH AS ALMOST NO INSTABILITY
PRESENT AND THE SYSTEM WILL BE FAST MOVING. SHOWERS WILL END BY
MON AFTERNOON AS SYSTEM EXITS OFF THE COAST. ANOTHER STRONG SURGE
OF COLD AIR WILL POUR INTO E NC WITH GUSTY NW WINDS DEVELOPING BY
AFTERNOON. IT STILL APPEARS THE COLD AIR WILL BE CHASING PRECIP
THEREFORE LITTLE CHANCE OF WRAP AROUND SNOW...THOUGH CANNOT
COMPLETELY RULE OUT A CHANGE IN MODEL SOLUTIONS THIS FAR OUT AND
WILL CLOSELY MONITOR TO SEE IF LOW TRACK SHIFTS A BIT FURTHER SOUTH.
COLD NIGHT ON MONDAY NIGHT ON TAP WITH LOWS DROPPING BACK TO THE
LOW 20S INLAND TO UPR 20S BEACHES WITH A BRISK NORTHERLY WIND
BRINGING WIND CHILLS INTO THE TEENS. TRANSIENT ARCTIC HIGH PRES
MOVES THROUGH THE AREA ON TUESDAY WITH LOW LEVEL THICKNESS VALS OF
1280-1290 M SUGGESTIVE OF HIGHS ONLY IN THE UPR 30S NORTH TO LOW
40S SOUTH UNDER SUNNY SKIES AND LIGHT WINDS.
E NC LOOKS TO REMAIN IN VCNTY OF STORM TRACK MID WEEK AS LONG
RANGE MODELS IN REMARKABLY GOOD AGREEMENT WITH A SOUTHERN STREAM
LOW EJECTING OUT OF THE GOM AND REACHING THE EASTERN SEABOARD
SOMETIME ON WED. TOO FAR OUT TO DETERMINE IF THE LOW WILL TRACK
INLAND OR OFF THE COAST...THOUGH IT APPEARS NOW THAT COLD AIR WILL
BE LOCKED TO THE WEST OF THE REGION PER ENSEMBLE HEIGHT FIELDS.
HOWEVER...THIS MAY CHANGE AS ARCTIC AIR WILL BE CLOSE ENOUGH TO
THE WEST AND NORTH TO WARRANT PLACING THE AREA IN A MONITORING
MODE FOR WINTER TYPE WEATHER. ANOTHER SURGE OF ARCTIC AIR POURS IN
BY LATE WEEK BEHIND THIS SYSTEM WITH MORE WINTER LIKE TEMPERATURES.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
SHORT TERM /THROUGH 06Z SATURDAY/...
AS OF 1 AM FRIDAY...HIGH CONFIDENCE IN A VFR FORECAST THROUGH THE
PERIOD. CEILINGS WILL LOWER TO AROUND 4000-5000 FEET THROUGH THE
EARLY MORNING HOURS AHEAD OF COLD FRONT...BUT QUICKLY BECOME
SCATTERED BY MID-MORNING AND CLEAR BY LATER IN THE DAY AS STRONG
COLD AIR ADVECTION KICKS IN BEHIND COLD FRONT. GUSTY NW WINDS ARE
EXPECTED BEHIND THE FRONT THIS AFTERNOON AND CONTINUING INTO
TONIGHT WHICH WILL PRECLUDE ANY FOG ISSUES.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 330 PM THU...THE GUSTY NW WINDS DIMINISH FRI NIGHT THROUGH
SAT AS HIGH PRESSURE BUILDS IN WITH CLEAR SKIES. NEXT CHANCE OF
PRECIPITATION ARRIVES SUN NIGHT WITH MVFR OR LOWER CONDITIONS
SUNDAY NIGHT INTO MONDAY WITH WIDESPREAD RAIN. LOW PRES AND COLD
FRONT MOVE AWAY MONDAY AFTERNOON WITH GUSTY NW WINDS DEVELOPING
THROUGH EARLY EVENING. HIGH PRES BUILDS IN MONDAY NIGHT AND IS
CENTERED OVER THE AREA ON TUESDAY.
&&
.MARINE...
SHORT TERM /THROUGH FRIDAY/...
AS OF 1 AM FRIDAY...SW WINDS WILL GRADUALLY INCREASE OVERNIGHT.
WHILE MOST LOCATIONS STILL IN THE 10 TO 15 KNOT RANGE...CURRENTLY
SEEING GUSTS TO 29 KNOTS AT DIAMOND BUOY. ONCE STRONG COLD FRONT
PASSES OFFSHORE IN THE MID-MORNING HOURS...TIGHT GRADIENT LEADS TO
GUSTY NW/N WINDS AT 20 TO 30 KNOTS THIS AFTERNOON INTO TONIGHT.
MAY UPGRADE PORTIONS OF THE COASTAL WATERS AND PERHAPS SOUNDS TO
GALE WARNINGS ON THE NEXT UPDATE.
BLEND OF NWPS AND PREVIOUS FCST USED FOR SEAS. HEIGHTS WILL BUILD
QUICKLY TO 5-7 FT SRN AND CENTRAL WATERS OVERNIGHT...THEN 7-10 FT
OUTER PORTIONS ALL WATERS WITH INCREASING NW WINDS FRIDAY.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 330 PM THU...GENERALLY POOR BOATING CONDITIONS THROUGH THE
EXTENDED PERIOD. GALE CONDITIONS LIKELY TO DEVELOP FRI EVENING
BEHIND PASSAGE OF STRONG COLD FRONT. NW WINDS WILL INC WITH GALES
MOST LIKELY FOR THE CENTRAL AND NORTHERN WATERS...AND POSSIBLY
EVEN THE EASTERN ALBEMARLE AND PAMLICO SOUNDS. THE GUSTY NW WINDS
WILL BEGIN TO DIMINISH BELOW GALE CRITERIA BY SAT MORNING THOUGH
SEAS WILL REMAIN HIGH ALL DAY FOR THE NORTHERN AND CENTRAL WATERS.
HAVE USED MAINLY THE LOCAL SWAN/NWPS OUTPUT AS THIS TENDS TO
PERFORM BEST WITH NW WINDS. SEAS WILL PEAK 12-15 FOR THE OUTER
NRN/CENTRAL WATERS LATE FRI NIGHT INTO EARLY SAT MORNING. SEAS
SHOULD FINALLY DROP BELOW 6 FT LATE SAT EVENING AS HIGH PRES
PASSES SOUTH OF THE WATERS. THIS WILL CAUSE WINDS TO SHIFT TO THE
SW BY LATE SAT NIGHT WITH SPEEDS GENERALLY AROUND 10 KT. THE SW
WINDS WILL INC TO SCA LEVELS BY LATE SUN NIGHT AS A LOW PRES
SYSTEM APPROACHES AND PASSES JUST NORTH OF THE WATERS. WINDS WILL
ABRUPTLY TURN NW ON MON AND INC TO POTENTIAL GALES AS STRONG COLD
AIR ADVECTION POURS INTO THE EASTERN SEABOARD. WINDS SHOULD
DIMINISH TO 5-15 KT TUESDAY AS HIGH PRES APPROACHES.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM EARLY THIS MORNING TO 10 AM EST
SATURDAY FOR AMZ135.
SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 10 AM EST
SATURDAY FOR AMZ130.
SMALL CRAFT ADVISORY UNTIL 1 AM EST SUNDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY UNTIL 1 PM EST SATURDAY FOR AMZ156-158.
SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 1 AM EST SUNDAY
FOR AMZ150.
&&
$$
SYNOPSIS...JBM
NEAR TERM...CTC
SHORT TERM...JBM
LONG TERM...TL
AVIATION...CTC/TL
MARINE...CTC/BTC/TL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1255 AM EST FRI JAN 30 2015
.SYNOPSIS...FOLLOWING A COLD FRONT MOVING THROUGH CENTRAL NORTH
CAROLINA THIS MORNING AND OFFSHORE BY AFTERNOON...HIGH PRESSURE
BUILDS OVER THE REGION FROM THE NORTHWEST. THE HIGH MOVES OFFSHORE
SATURDAY NIGHT INTO SUNDAY. A LOW PRESSURE SYSTEM SHOULD MOVE INTO
THE REGION BY SUNDAY NIGHT.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 1020 PM EST THURSDAY...
OVERNIGHT...MID LEVEL TROUGH AND ACCOMPANYING SFC COLD FRONT WILL
CROSS CENTRAL NC OVERNIGHT. LEAD MID-UPPER LEVEL TROUGH RESPONSIBLE
FOR THE BAND OF RAIN/SLEET THIS AFTERNOON HAS LONG EXITED THE
REGION. FORCING WITH THE SFC FRONT MAY LEAD TO FEW LIGHT RAIN
SHOWERS LATER TONIGHT...MAINLY EAST OF HIGHWAY 1.
SFC FRONT SHOULD CROSS THE WESTERN PIEDMONT BETWEEN MIDNIGHT-
2AM...THE HIGHWAY 1 CORRIDOR 2-4 AM...AND EXIT OUR COASTAL PLAIN
COUNTIES SHORTLY BEFORE DAYBREAK.
DUE TO THE CLOUD COVER AND LIGHT MIXING...TEMPS WILL HOLD STEADY FOR
A GOOD PART OF THE OVERNIGHT HOURS THAN FALL TOWARD DAYBREAK WITH
THE PASSAGE OF THE 850MB TROUGH. MIN TEMPS NEAR 30 NW TO UPPER 30S
SE. -WSS
A BLUSTERY/WINDY DAY UNDER CHILLY TEMPS IN STORE ON FRIDAY AS STRONG
HIGH PRESSURE SLIDES EAST WHILE THE PRESSURE GRADIENT REMAINS QUITE
TIGHT BETWEEN THE RIDGE AND DEEPENING LOW PRESSURE OFF NEW ENGLAND.
APPEARS GUSTS TOPPING 30-35 MPH AT TIMES MAY APPROACH ADVISORY
LEVELS FOR A BRIEF PERIOD GIVEN DEEP MIXING AND AIDED VIA A FINAL
PASSING MID LEVEL WAVE TO THE NORTH. OTHERWISE STRONG SUBSIDENCE
SHOULD LEAD TO MAINLY SUNNY SKIES WITH HIGHS MOSTLY IN THE 40S GIVEN
HEATING OF VERY DRY AIR.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 235 PM EST THURSDAY...
COLD ADVECTION CONTINUES AS SURFACE HIGH APPROACHES FROM WEST BUT
WITH SURFACE HIGH STILL WEST OF APPALACHIANS BY 12Z SAT DO NOT THINK
CENTRAL NORTH CAROLINA WILL COMPLETELY DECOUPLE...DESPITE MAINLY
CLEAR SKIES. CHANCE OF SOME CIRRUS MOVING IN LATE FRIDAY NIGHT TOO
THOUGH. SO WILL NOT GO ANY COLDER THAN GUIDANCE FOR LOWS...WHICH IS
PRETTY CONSISTENT IN THE LOW 20S MOST OF THE AREA.
DRY HIGH PRESSURE DOMINATES THEN THROUGH SATURDAY NIGHT...AND MAY
CONTINUE ITS INFLUENCE INTO EARLY SUNDAY BEFORE MOISTURE INCREASES
FROM THE WEST AHEAD OF NEXT CLIPPER TYPE SYSTEM. WITH DRY LOW LEVELS
INITIALLY IT COULD TAKE PRECIP A WHILE TO MAKE IT TO THE GROUND ON
SUNDAY...STARTING IN WEST BY MIDDAY AND SPREADING TO THE EAST BY
LATE IN DAY OR EARLY EVENING. GIVEN DAYTIME START TO PRECIP AND WARM
ADVECTION AHEAD OF DEVELOPING BUT RATHER WEAK SURFACE LOW OVER
TENNESSEE VALLEY...NO CONCERNS ABOUT ANY LIGHT WINTRY PRECIP DESPITE
EVAPORATIVE COOLING INTO DRY AIRMASS.
MODEL CONSENSUS DOES AGREE THAT PRECIP CHANCES WILL BE HIGHEST
SUNDAY NIGHT AND QPF VALUES OF A QUARTER INCH OR HIGHER ARE
POSSIBLE...GFS WITH ALMOST A HALF AN INCH...BUT SEE NO CONCERNS AT
ALL FOR BOUNDARY LAYER OF SURFACE TEMPS TO SUPPORT ANY WINTRY PRECIP
EVEN OVERNIGHT AHEAD OF THE FRONT. IN FACT IT MAY BE WARMING
OVERNIGHT SUNDAY NIGHT...BUT AS YET HAVE NOT REFLECTED THAT ON
HOURLY TEMPS...BUT DO NOT HAVE IT DROPPING VERY MUCH EITHER SUNDAY
NIGHT. LATEST MEX GUIDANCE FROM GFS MUCH MILDER AND TRENDED UP A BIT
BUT NOT THAT HIGH AS OF YET. LOWS SUNDAY NIGHT IN UPPER 30S
NORTHWEST TO MID 40S SOUTHEAST...BUT SEE POTENTIAL FOR IT TO BE EVEN
MILDER.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 300 PM EST THURSDAY...
MONDAY: MODEL TRENDS...AND NOW A LITTLE BETTER CONSENSUS...TO DEEPEN
AND SLOW THE EXITING LOW PRESSURE SYSTEM AND FRONT AS IT MOVES OFF
THE MID ATLANTIC COAST COULD NOW MEAN SOME LINGERING SHOWERS ACROSS
CENTRAL NORTH CAROLINA FOR AT LEAST EARLY IN THE DAY MONDAY...BUT
SHOULD PUSH EAST BY AFTERNOON. STILL GOING TO KEEP A SLIGHT CHANCE
EAST OF RALEIGH FOR SECOND HALF OF DAY IN CASE ADDITIONAL SLOWING
OCCURS. COLDER AIR THEN ALSO A LITTLE SLOWER TO FILTER IN BEHIND
SYSTEM...SO BUMPED UP HIGHS JUST A COUPLE DEGREES. MAY END UP BEING
NEARLY STEADY MUCH OF DAY AND DROPPING QUICKLY BY EARLY AFTERNOON
BUT GIVEN THE UNCERTAINTY IN TIMING BEING FOUR DAYS OUT...DECIDED
NOT TO SHOW THIS NON DIURNAL TREND JUST YET.
MONDAY NIGHT THROUGH TUESDAY NIGHT: CHILLY HIGH PRESSURE TO BUILD IN
BEHIND THE FRONT...1025 TO 1030 MB STRENGTH. HIGH CONFIDENCE THAT
ANY PRECIP WILL BE WELL EAST OF THE AREA BY MONDAY NIGHT...WITH THE
COLD AND DRY HIGH PRESSURE IN CONTROL THROUGH TUESDAY AND INTO
TUESDAY NIGHT....BUT MILDER TUES NIGHT WITH WARM ADVECTION AND CLOUD
COVER ALREADY INCREASING AHEAD OF NEXT SYSTEM IN THIS PROGRESSIVE
PATTERN.
MORE UNCERTAINTY COMES INTO PLAY BY MID WEEK AS NORTHER AND SOUTHERN
BRANCHES OF THE JET STREAM TRY TO PHASE...AND A COLD FRONT
APPROACHES FROM THE WEST BY LATE WED...WHILE SHORT WAVE ENERGY IN
THE SOUTHERN STREAM TAPS SOME MOISTURE FROM THE GULF WHICH HEADS
NORTHEAST TOWARD NORTH CAROLINA. CURRENTLY THERE ARE FAIRLY
SIGNIFICANT DIFFERENCES IN THE TIMING AND AMOUNT OF MOISTURE WITH
THIS SYSTEM...WITH 00Z ECMWF FASTER AND INCREASING THE CHANCES FOR
PRECIP AS EARLY AS LATE TUESDAY NIGHT INTO WED MORNING...WITH THE
12Z GFS NOT UNTIL DURING THE DAY WED. MOST GFS ENSEMBLES SEEM TO BE
IN THIS CAMP AS WELL. SO AM NOT INDICATING ANY CHANCE POPS UNTIL
DURING THE DAY WED AT THIS POINT. GFS MODEL SOUNDINGS SUGGEST IF
THIS COMES IN EARLY ENOUGH THERE COULD BE SOME LIGHT WINTRY MIX AT
THE ONSET BUT THINK THIS WILL BE VERY LIGHT AND HAVE NO IMPACT. MOST
LIKELY PRECIP WILL HOLD OFF UNTIL LATER WHEN BOUNDARY LAYER TEMPS
ARE WARM ENOUGH TO SUPPORT RAIN ONLY. DO HAVE SOME CHANCE RAIN AND
SNOW IN THE GRIDS FOR WHEN TEMPS ARE AT OR BELOW FREEZING EARLY
WED...AND AGAIN LATE WED NIGHT BEHIND COLD FRONT...BUT THIS MAY
AMOUNT TO NO MORE THAN FLURRIES.
THEN BETTER CONFIDENCE IN BLUSTERY AND COLDER FOR THURSDAY BEHIND
FRONT...AND MAY EVENTUALLY NEED TO GO COLDER THAN CURRENT FCST BUT
HEDGING SOMEWHAT FOR NOW SINCE GFS IN PARTICULAR TENDS TO HAVE A
COLD BIAS BEHIND FRONTS THAT FAR OUT.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 1255 AM FRIDAY...
VFR CONDITIONS ARE EXPECTED OVERALL THROUGH THE 06Z VALID TAF
PERIOD. A COLD FRONT MOVES THROUGH CENTRAL NORTH CAROLINA THIS
MORNING WHICH WILL RESULT IN RAPIDLY VEERING WINDS TO THE NORTHWEST
WITH SPEEDS INCREASING TO GUSTS AROUND 30KT BY LATE MORNING. WHILE
THE GFS MODEL SHOWS THE POTENTIAL FOR WIND GUSTS A LITTLE ABOVE
THAT...THE NAM AND RAP MODELS ARE LESS...AND MOMENTUM TRANSFER
SPEEDS TOP OUT AT ABOUT 30KT ON ALL THREE WHICH WILL BE THE CAP FOR
THE CENTRAL NORTH CAROLINA TAFS. SOME OF THE CONVECTIVE-ALLOWING
MODELS SUGGEST A FEW SHOWERS WITH THE FRONT EARLY THIS MORNING
AROUND DAYBREAK NORTHEAST OF KRWI AND TOWARD KFAY...AND HAVE NOTED
VCSH IN THE TAF AT KFAY WHERE THE LOW-LEVEL MOISTURE IS GREATER THIS
EARLY MORNING. WITH A STRONG MID-LEVEL DISTURBANCE MOVING THROUGH
TODAY...THERE IS THE POTENTIAL FOR SHALLOW CONVECTION...BROKEN VFR
CLOUDS AND MAYBE A LITTLE VIRGA KRDU AND EAST EARLY THIS AFTERNOON.
WINDS DIMINISH THIS EVENING DIURNALLY THOUGH EXPECT NORTHWEST WINDS
AOA 30KT AT AND ABOVE 2000FT.
BEYOND THE 06Z VALID TAF PERIOD...VFR CONDITIONS CONTINUE INTO
SUNDAY...WITH AREAS OF HIGH CLOUDS MOVING IN SATURDAY NIGHT
GRADUALLY LOWERING SUNDAY. A CHANCE OF RAIN IN THE WESTERN PIEDMONT
SUNDAY AFTERNOON FOLLOWED BY BETTER CHANCES BY SUNDAY NIGHT ALONG
WITH THE POTENTIAL OF SUB-VFR CONDITIONS INTO MONDAY MORNING. VFR
CONDITIONS ARE EXPECTED TO RETURN BY MONDAY AFTERNOON ACCOMPANIED BY
BREEZY CONDITIONS ONCE AGAIN...WITH THE VFR CONDITIONS THEN
CONTINUING THROUGH TUESDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...WSS/JH
SHORT TERM...SK
LONG TERM...SK
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
946 PM CST SAT JAN 31 2015
.UPDATE...
ISSUED AT 944 PM CST SAT JAN 31 2015
NO SIGNIFICANT CHANGES REQUIRED WITH THIS UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 03 UTC AS THE FOCUS FOR SNOWFALL
WILL CONTINUE TO SHIFT INTO FAR SOUTH CENTRAL NORTH DAKOTA THROUGH
THE NIGHT. FRONTOGENESIS AND DENDRITIC OMEGA ARE DECREASING AS
EXPECTED...MARKING A SLOW DECLINE IN SNOWFALL INTENSITY.
UPDATE ISSUED AT 547 PM CST SAT JAN 31 2015
RADAR TRENDS THROUGH 2330 UTC ARE ALIGNED WELL WITH THE 20
THROUGH 22 UTC HRRR ITERATIONS...AND WILL WEIGH HEAVILY UPON THEIR
SOLUTIONS FOR THE REMAINDER OF THE NIGHT. EXPECT A BAND OF
MODERATE TO AT TIMES HEAVY SNOW TO CONTINUE TO DEVELOP FROM CENTER
THROUGH BISMARCK...NEW SALEM...FLASHER...CARSON AND MOTT THROUGH
03 UTC IN ASSOCIATION WITH STRENGTHENING 850-700 MB FRONTOGENESIS.
WHILE SNOW WILL CONTINUE THEREAFTER...PEAK INTENSITIES WILL BEGIN
TO SLOWLY DECREASE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 245 PM CST SAT JAN 31 2015
.SHORT TERM...TONIGHT AND SUNDAY...
MAIN ISSUED THIS FORECAST PERIOD WILL BE SNOW POTENTIAL THIS
AFTERNOON AND EVENING. SNOW IS STILL FORECAST TO REMAIN BELOW
ADVISORY CRITERIA WITH FAIRLY WIDESPREAD SNOW AMOUNTS OF 3 INCHES
ACROSS WEST CENTRAL ND THIS AFTERNOON WITH 2 TO 3 INCHES SPREADING
INTO THE SOUTH CENTRAL TONIGHT. AN ISOLATED 4 INCH AMOUNT IS
POSSIBLE BUT NOT WIDESPREAD. THEN WIND CHILLS BECOME A CONCERN
ACROSS THE NORTH CENTRAL THROUGH THE NORTHERN JAMES RIVER VALLEY
TONIGHT INTO SUNDAY MORNING. LATEST RADAR TRENDS SHOW THE SNOW THIS
AFTERNOON IS CONCENTRATED ACROSS THE WEST CENTRAL WHERE UP TO 3
INCHES MAY FALL BY EARLY EVENING. THEN THIS EVENING THEN SNOW WILL
BE FOCUSED ALONG AN H300 JET REGION WHICH EXTENDS NORTHEAST TO
SOUTHWEST ACROSS WESTERN NORTH DAKOTA. THE LATEST HRRR RUNS FOLLOW
THE JET DYNAMICS AND FORM A SNOW BAND THAT EXTENDS FROM SOUTHWEST
NORTH DAKOTA INTO THE SOUTH CENTRAL BETWEEN 00Z-06Z. BELIEVE THERE
WILL ANOTHER 3 INCH BAND OF SNOW FROM BOWMAN NORTHEAST TO BISMARCK.
THE MOST RAPIDLY CHANGING WEATHER WILL BE FOUND SOUTH CENTRAL WHERE
THE PARTLY SUNNY SKIES THIS AFTERNOON WILL QUICKLY CHANGE TO SNOW.
BUFKIT SOUNDINGS FROM DICKINSON TO BISMARCK THIS EVENING SHOW A
FAIRLY DEEP DENDRITIC GROWTH ZONE WITH SUPER SATURATION WITH RESPECT
TO ICE. THUS THERE WILL BE GOOD SNOW POTENTIAL FROM THE LIMITED QPF
THAT HAS BEEN CONSISTENTLY FORECAST FOR THIS SYSTEM.
THIS EVENING...WILL ISSUE A WIND CHILL ADVISORY FOR WIND CHILLS 25
TO 30 BELOW EXTENDING FROM BOTTINEAU COUNTY SOUTHEAST THROUGH
STUTSMAN COUNTY. TOWNS INCLUDED IN THIS AREA INCLUDE
BOTTINEAU...RUGBY... HARVEY AND JAMESTOWN.
BY SUNDAY MORNING THE SNOW WILL END. SHOULD SEE CONSIDERABLE
SUNSHINE BOT COLD TEMPERATURES SUNDAY
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 245 PM CST SAT JAN 31 2015
THE PATTERN REMAINS UNSETTLED FOR THE EARLY AND LATTER PORTIONS OF
THE LONG TERM PERIOD. SHORTWAVE TROUGHS CONTINUE TO CIRCULATE AROUND
THE HUDSON BAY LOW AND INTO NORTH DAKOTA. ALTHOUGH THERE APPEARS TO
BE A BREAK WEDNESDAY INTO EARLY FRIDAY...BOTH THE GFS AND ECMWF ARE
HINTING AT ANOTHER SYSTEM FRIDAY NIGHT THROUGH SATURDAY.
SUNDAY NIGHT AND MONDAY...NOT A LOT OF CHANGE FROM PREVIOUS RUNS AND
THOUGHTS AS THIS WILL BE A BRIEF/MINOR WARM AIR ADVECTION
PRECIPITATION EVENT MONDAY. SOUTHWEST WINDS SUNDAY NIGHT WILL QUICKLY
SHIFT TO THE NORTHWEST DURING THE MORNING IN THE WEST AND AFTERNOON
IN THE CENTRAL AS COLD AIR ADVECTION AGAIN TAKES CONTROL. PER
NAM/GFS BUFKIT SOUNDINGS...HAVE TEMPERED HIGHS IN THE SOUTHWEST AS
COLD AIR ADVECTION TAKES OVER BY MID TO LATE MORNING AND BASICALLY
PUTS A CAP ON RISING TEMPERATURES. SNOWFALL POTENTIAL REMAINS LIGHT
WITH AROUND A HALF INCH ALONG AND WEST OF THE MISSOURI RIVER.
FOR TUESDAY...IT APPEARS THE STRONGER BAROCLINIC ZONE ASSOCIATED
WITH AN ARCTIC INTRUSION REMAINS IN SOUTH CENTRAL MONTANA AND
WESTERN SOUTH DAKOTA. THE GFS HAS SHIFTED THE MAIN SNOW AXIS ACROSS
THE FAR SOUTHWEST. THE NAM/ECMWF ALSO INDICATE A WEAKER SCENARIO BUT
HAVE THIS AREA FARTHER EAST AS WELL. QPF TODAY VERSUS THE LAST FEW
RUNS HAVE LOWERED QUITE A BIT. SNOWFALL ACCUMULATIONS ARE NOW MORE
LIKELY TO RANGE FROM 1 TO 1.5 INCHES ACROSS WESTERN AND SOUTH
CENTRAL NORTH DAKOTA.
WEDNESDAY THROUGH SATURDAY...MAINLY DRY CONDITIONS CAN BE EXPECTED AS
NORTHWEST FLOW CONTINUES WEDNESDAY WITH ARCTIC AIR AND SURFACE HIGH
PRESSURE DOMINATING. HIGHS WILL RANGE FROM AROUND ZERO IN THE TURTLE
MOUNTAINS TO 20 DEGREES ABOVE ZERO IN THE SOUTHWEST. WARM AIR
ADVECTION ONCE AGAIN COMMENCES THURSDAY AND FRIDAY. AN ALBERTA
CLIPPER WITH A FAIRLY TIGHT BAROCLINIC ZONE IS FORECAST TO DEVELOP
ACROSS CENTRAL AND NORTHERN NORTH DAKOTA FRIDAY THROUGH SATURDAY.
THE ECMWF IS MUCH COLDER AS THE BAROCLINIC ZONE SAGS FURTHER SOUTH.
BOTH MODELS DEPICT DECENT PRECIPITATION DEVELOPING DURING THIS
PERIOD AND SNOW WOULD BE THE LIKELY CANDIDATE IN THE NORTH. THERE IS
A POTENTIAL FOR A WINTRY MIX IN/AROUND THE WARMER SIDE OF THE
BAROCLINIC ZONE. WILL NEED TO MONITOR THIS IN THE COMING DAYS. HIGH
TEMPERATURES FRIDAY/SATURDAY WILL DEPEND ON WHERE THE BAROCLINIC
ZONE SETS UP ACROSS SOUTHWEST/NORTHERN NORTH DAKOTA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY)
ISSUED AT 945 PM CST SAT JAN 31 2015
IFR CONDITIONS IN SNOW CONTINUE AT KDIK AND KBIS THROUGH 07-09
UTC. CONDITIONS IMPROVING TO VFR AT KISN BY 04-05 UTC. A BRIEF
PERIOD OF IFR/MVFR VISIBILITY IN SNOW IS POSSIBLE AT KJMS LATE THIS
EVENING...OTHERWISE VFR. KMOT VFR THROUGH THE PERIOD AS HIGH
PRESSURE BUILDS ACROSS THE AREA.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM CST SUNDAY FOR NDZ004-005-012-
013-022-023-025-036-037.
&&
$$
UPDATE...AYD
SHORT TERM...WAA
LONG TERM...KS
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
547 PM CST SAT JAN 31 2015
.UPDATE...
ISSUED AT 547 PM CST SAT JAN 31 2015
RADAR TRENDS THROUGH 2330 UTC ARE ALIGNED WELL WITH THE 20
THROUGH 22 UTC HRRR ITERATIONS...AND WILL WEIGH HEAVILY UPON THEIR
SOLUTIONS FOR THE REMAINDER OF THE NIGHT. EXPECT A BAND OF
MODERATE TO AT TIMES HEAVY SNOW TO CONTINUE TO DEVELOP FROM CENTER
THROUGH BISMARCK...NEW SALEM...FLASHER...CARSON AND MOTT THROUGH
03 UTC IN ASSOCIATION WITH STRENGTHENING 850-700 MB FRONTOGENESIS.
WHILE SNOW WILL CONTINUE THEREAFTER...PEAK INTENSITIES WILL BEGIN
TO SLOWLY DECREASE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 245 PM CST SAT JAN 31 2015
.SHORT TERM...TONIGHT AND SUNDAY...
MAIN ISSUED THIS FORECAST PERIOD WILL BE SNOW POTENTIAL THIS
AFTERNOON AND EVENING. SNOW IS STILL FORECAST TO REMAIN BELOW
ADVISORY CRITERIA WITH FAIRLY WIDESPREAD SNOW AMOUNTS OF 3 INCHES
ACROSS WEST CENTRAL ND THIS AFTERNOON WITH 2 TO 3 INCHES SPREADING
INTO THE SOUTH CENTRAL TONIGHT. AN ISOLATED 4 INCH AMOUNT IS
POSSIBLE BUT NOT WIDESPREAD. THEN WIND CHILLS BECOME A CONCERN
ACROSS THE NORTH CENTRAL THROUGH THE NORTHERN JAMES RIVER VALLEY
TONIGHT INTO SUNDAY MORNING. LATEST RADAR TRENDS SHOW THE SNOW THIS
AFTERNOON IS CONCENTRATED ACROSS THE WEST CENTRAL WHERE UP TO 3
INCHES MAY FALL BY EARLY EVENING. THEN THIS EVENING THEN SNOW WILL
BE FOCUSED ALONG AN H300 JET REGION WHICH EXTENDS NORTHEAST TO
SOUTHWEST ACROSS WESTERN NORTH DAKOTA. THE LATEST HRRR RUNS FOLLOW
THE JET DYNAMICS AND FORM A SNOW BAND THAT EXTENDS FROM SOUTHWEST
NORTH DAKOTA INTO THE SOUTH CENTRAL BETWEEN 00Z-06Z. BELIEVE THERE
WILL ANOTHER 3 INCH BAND OF SNOW FROM BOWMAN NORTHEAST TO BISMARCK.
THE MOST RAPIDLY CHANGING WEATHER WILL BE FOUND SOUTH CENTRAL WHERE
THE PARTLY SUNNY SKIES THIS AFTERNOON WILL QUICKLY CHANGE TO SNOW.
BUFKIT SOUNDINGS FROM DICKINSON TO BISMARCK THIS EVENING SHOW A
FAIRLY DEEP DENDRITIC GROWTH ZONE WITH SUPER SATURATION WITH RESPECT
TO ICE. THUS THERE WILL BE GOOD SNOW POTENTIAL FROM THE LIMITED QPF
THAT HAS BEEN CONSISTENTLY FORECAST FOR THIS SYSTEM.
THIS EVENING...WILL ISSUE A WIND CHILL ADVISORY FOR WIND CHILLS 25
TO 30 BELOW EXTENDING FROM BOTTINEAU COUNTY SOUTHEAST THROUGH
STUTSMAN COUNTY. TOWNS INCLUDED IN THIS AREA INCLUDE
BOTTINEAU...RUGBY... HARVEY AND JAMESTOWN.
BY SUNDAY MORNING THE SNOW WILL END. SHOULD SEE CONSIDERABLE
SUNSHINE BOT COLD TEMPERATURES SUNDAY
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 245 PM CST SAT JAN 31 2015
THE PATTERN REMAINS UNSETTLED FOR THE EARLY AND LATTER PORTIONS OF
THE LONG TERM PERIOD. SHORTWAVE TROUGHS CONTINUE TO CIRCULATE AROUND
THE HUDSON BAY LOW AND INTO NORTH DAKOTA. ALTHOUGH THERE APPEARS TO
BE A BREAK WEDNESDAY INTO EARLY FRIDAY...BOTH THE GFS AND ECMWF ARE
HINTING AT ANOTHER SYSTEM FRIDAY NIGHT THROUGH SATURDAY.
SUNDAY NIGHT AND MONDAY...NOT A LOT OF CHANGE FROM PREVIOUS RUNS AND
THOUGHTS AS THIS WILL BE A BRIEF/MINOR WARM AIR ADVECTION
PRECIPITATION EVENT MONDAY. SOUTHWEST WINDS SUNDAY NIGHT WILL QUICKLY
SHIFT TO THE NORTHWEST DURING THE MORNING IN THE WEST AND AFTERNOON
IN THE CENTRAL AS COLD AIR ADVECTION AGAIN TAKES CONTROL. PER
NAM/GFS BUFKIT SOUNDINGS...HAVE TEMPERED HIGHS IN THE SOUTHWEST AS
COLD AIR ADVECTION TAKES OVER BY MID TO LATE MORNING AND BASICALLY
PUTS A CAP ON RISING TEMPERATURES. SNOWFALL POTENTIAL REMAINS LIGHT
WITH AROUND A HALF INCH ALONG AND WEST OF THE MISSOURI RIVER.
FOR TUESDAY...IT APPEARS THE STRONGER BAROCLINIC ZONE ASSOCIATED
WITH AN ARCTIC INTRUSION REMAINS IN SOUTH CENTRAL MONTANA AND
WESTERN SOUTH DAKOTA. THE GFS HAS SHIFTED THE MAIN SNOW AXIS ACROSS
THE FAR SOUTHWEST. THE NAM/ECMWF ALSO INDICATE A WEAKER SCENARIO BUT
HAVE THIS AREA FARTHER EAST AS WELL. QPF TODAY VERSUS THE LAST FEW
RUNS HAVE LOWERED QUITE A BIT. SNOWFALL ACCUMULATIONS ARE NOW MORE
LIKELY TO RANGE FROM 1 TO 1.5 INCHES ACROSS WESTERN AND SOUTH
CENTRAL NORTH DAKOTA.
WEDNESDAY THROUGH SATURDAY...MAINLY DRY CONDITIONS CAN BE EXPECTED AS
NORTHWEST FLOW CONTINUES WEDNESDAY WITH ARCTIC AIR AND SURFACE HIGH
PRESSURE DOMINATING. HIGHS WILL RANGE FROM AROUND ZERO IN THE TURTLE
MOUNTAINS TO 20 DEGREES ABOVE ZERO IN THE SOUTHWEST. WARM AIR
ADVECTION ONCE AGAIN COMMENCES THURSDAY AND FRIDAY. AN ALBERTA
CLIPPER WITH A FAIRLY TIGHT BAROCLINIC ZONE IS FORECAST TO DEVELOP
ACROSS CENTRAL AND NORTHERN NORTH DAKOTA FRIDAY THROUGH SATURDAY.
THE ECMWF IS MUCH COLDER AS THE BAROCLINIC ZONE SAGS FURTHER SOUTH.
BOTH MODELS DEPICT DECENT PRECIPITATION DEVELOPING DURING THIS
PERIOD AND SNOW WOULD BE THE LIKELY CANDIDATE IN THE NORTH. THERE IS
A POTENTIAL FOR A WINTRY MIX IN/AROUND THE WARMER SIDE OF THE
BAROCLINIC ZONE. WILL NEED TO MONITOR THIS IN THE COMING DAYS. HIGH
TEMPERATURES FRIDAY/SATURDAY WILL DEPEND ON WHERE THE BAROCLINIC
ZONE SETS UP ACROSS SOUTHWEST/NORTHERN NORTH DAKOTA.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 546 PM CST SAT JAN 31 2015
IFR TO LIFR CONDITIONS IN SNOW AT KDIK AND KBIS TONIGHT. SNOW
ENDING AT KISN BY 02 UTC. KMOT AND KJMS LOOK TO REMAIN ON THE
FRINGE OF THE SNOW BAND ACROSS SOUTHWEST AND SOUTH CENTRAL NORTH
DAKOTA TONIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM CST SUNDAY FOR NDZ004-005-012-
013-022-023-025-036-037.
&&
$$
UPDATE...AYD
SHORT TERM...WAA
LONG TERM...KS
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1156 AM CST FRI JAN 30 2015
.UPDATE...
ISSUED AT 1148 AM CST FRI JAN 30 2015
COOL AIR STRATUS LEADING EDGE MOVING SOUTH INTO THE SOURIS RIVER
VALLEY OF NORTHWEST NORTH DAKOTA. THIS AREA SEEMS TO BE A BIT
FASTER THAN THE PREVIOUS FORECAST. ALSO FOG AND LOW CEILINGS SHOWING
UP AT ESTEVAN. ADDED PATCHY FOG FOR THE AFTERNOON ACROSS
BURKE..WARD AND RENVILLE COUNTIES AS LOW CLOUDS MOVE OVER THE
AREA. ALSO LOWERED MAX TEMPS WHERE CLOUDS ARE FORMING TO MID 20S.
UPDATE ISSUED AT 849 AM CST FRI JAN 30 2015
CLOUDS HAVE CLEARED ACROSS THE REGION THIS MORNING IN MODERATE
WARM ADVECTION. MORNING TEMPERATURES ARE IN THE TEENS AND LOWER
20S WHICH IS QUITE MILD FOR THIS TIME OF THE YEAR. UPDATE TO CLOUDS
THE ONLY CHANGE.
UPDATE ISSUED AT 639 AM CST FRI JAN 30 2015
MAINLY CLEAR SKIES ACROSS WESTERN NORTH DAKOTA THIS MORNING. AN
AREA OF MVFR-IFR CLOUDS FROM BOTTINEAU TO HARVEY AND WISHEK WILL
CONTINUE TO MOVE EAST THIS MORNING ON THE BACK SIDE OF HIGH
PRESSURE OVER MINNESOTA AND AHEAD OF AN ADVANCING WARM FRONT
MOVING INTO WESTERN NORTH DAKOTA. MADE SOME MINOR SKY COVER
ADJUSTMENTS BASED ON LATEST SATELLITE AND BUMPED UP SOUTHERLY
WINDS JUST A LITTLE THIS MORNING OVER THE EASTERN FORECAST AREA.
UPDATED TEXT PRODUCTS WILL BE SENT SHORTLY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CST FRI JAN 30 2015
THE MAIN FOCUS FOR THE SHORT TERM IS CLOUDS ACROSS THE JAMES VALLEY
AND AFTERNOON TEMPERATURES.
EARLY THIS MORNING AN AREA OF LOW STRATUS CONTINUES TO DEVELOP
ACROSS THE SOUTHERN JAMES RIVER VALLEY AND PUSH NORTH. THE HRRR IS
DOING A REASONABLE JOB DEPICTING THE CURRENT AREA OF STRATUS IN
THE 925MB MOISTURE FIELD. THE HRRR HAS THE AREA OF STRATUS
LIFTING OFF TO THE NORTHEAST AROUND 8 AM.
TEMPERATURES TODAY WILL BE LARGELY DEPENDENT ON THE PROGRESSION OF
THE WARM AND COLD FRONTS ASSOCIATED WITH A SURFACE LOW...CURRENTLY
CENTERED OVER NORTHEAST MONTANA. MOST OF THE OPERATIONAL MODELS
HAVE THE WARM FRONT THROUGH THE REGION BY ABOUT 11 AM. WINDS THEN SHIFT
FROM THE NORTHWEST AND THE COLD FRONT DIVES SOUTHEAST ACROSS THE
AREA THIS AFTERNOON. IT APPEARS THE SOUTHWEST WILL BE FAVORED FOR
A NICE QUICK WARM UP BEFORE THE COLD FRONT MOVES THROUGH. WITH
PLENTY OF SUNSHINE...WEST DOWNSLOPING WINDS AND A WARM FRONT
NEARBY THE SOUTHWEST SHOULD SEE TEMPERATURES APPROACHING THE LOW
50S. THE NORTH SHOULD REMAIN COOLER AS THE COLD FRONT WILL ENTER
EARLIER AND COLD AIR ADVECTION TAKE HOLD.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 338 AM CST FRI JAN 30 2015
MAIN FORECAST HIGHLIGHTS ARE COLD AND UNSETTLED WEATHER THROUGH AT
LEAST MID WEEK WITH A NUMBER OF LIGHT SNOW EVENTS. THEN POSSIBLY A
RETURN TO MORE MILD CONDITIONS AT THE END OF THE EXTENDED PERIOD.
DETERMINISTIC MODELS ARE IN PRETTY GOOD AGREEMENT EARLY IN PERIOD
AND USED A MODEL BLEND WITH WPC QPF FOR SNOW ACCUMULATIONS.
WITH THE SATURDAY SYSTEM...00 UTC FRIDAY MODELS HAVE FLIPPED A BIT
FROM 24 HOURS AGO. THE GFS/ECMWF ARE NOW FARTHER NORTH AND EAST
WHILE THE GEM HAS SHIFTED FARTHER SOUTHWEST WITH THE HIGHEST QPF.
HOWEVER A BLEND STILL YIELDS A REASONABLE ESTIMATE...CLOSE TO WPC
FORECAST AND SIMILAR TO OUR PREVIOUS FORECAST. SYNOPTIC SCALE UPPER
LEVEL FORCING WILL DEVELOP OVER EASTERN MONTANA AND WESTERN NORTH
DAKOTA SATURDAY...ASSOCIATED WITH A 120KT UPPER LEVEL JET DROPPING
INTO MONTANA FROM BRITISH COLUMBIA. MEANWHILE...SHORTWAVE IMPULSES
MOVING THROUGH THE UPPER FLOW WILL INTERACT WITH A LOW LEVEL
BAROCLINIC ZONE OVER THIS SAME AREA. THIS SHOULD RESULT IN A
WIDESPREAD AREA OF LIGHT SNOW LATE FRIDAY NIGHT THROUGH SATURDAY
NIGHT ACROSS WESTERN AND MOST OF CENTRAL NORTH DAKOTA. HAVE
EXPANDED CATEGORICAL POPS SLIGHTLY FROM PREVIOUS FORECAST. OTHERWISE
THE ONLY CHANGE WAS TO EXPAND CHANCE POPS A LITTLE FARTHER NORTH.
FORECAST SNOW AMOUNTS ARE GENERALLY 1 TO 2.5 INCHES ACROSS MOST OF
THE FORECAST AREA...BUT TAPERING QUICKLY TO LITTLE IF ANY
ACCUMULATION FROM AROUND SHERWOOD TO RUGBY AND CARRINGTON.
ANOTHER UPPER LEVEL IMPULSE TRACKS ACROSS THE FORECAST AREA ON
MONDAY. THERE ARE DETERMINISTIC MODEL DIFFERENCES...BUT IN GENERAL
IT LOOKS LIKE ANOTHER WIDESPREAD AREA OF SNOW...BUT WITH LESSER
AMOUNTS OF AN INCH AND A HALF OR LESS. THIS SYSTEM IS QUICKLY
FOLLOWED BY ANOTHER MORE VIGOROUS SYSTEM ASSOCIATED WITH ANOTHER
STRONG UPPER LEVEL JET TRAVERSING THE ROCKIES WHICH INDUCES SURFACE
LOW PRESSURE OVER THE MONDAY REGION TUESDAY. AGAIN...WIDESPREAD
SNOWS SPREADING ACROSS THE FORECAST AREA...GENERALLY SUB ADVISORY
CATEGORY SNOW. RIGHT NOW IT APPEARS THE SOUTHWEST QUARTER WOULD
RECEIVE THE HIGHEST SNOW AMOUNTS...BUT THIS FAR OUT THINGS CAN
CERTAINLY CHANGE. THIS SYSTEM HAS ALREADY TRENDED FARTHER NORTH AS
PREVIOUS RUNS SUPPRESSED PRECIPITATION FARTHER SOUTH. WILL NEED TO
CONTINUE TO MONITOR THIS SYSTEM.
BEYOND THE TUESDAY SYSTEM...THE GFS/GEM SUPPRESS ADDITIONAL SNOWS
SOUTH OF THE FORECAST AREA AS VERY COLD HIGH PRESSURE DROPS SOUTH
INTO THE NORTHERN PLAINS. THE ECMWF HOWEVER KEEPS A QUASI ZONAL FLOW
OVER THE REGION LONG ENOUGH TO BRING ANOTHER IMPULSE ACROSS THE
FORECAST AREA TUESDAY NIGHT THROUGH WEDNESDAY MORNING...GIVING US
ONE LAST SHOT OF WIDESPREAD LIGHT SNOWS BEFORE COLD HIGH PRESSURE
SETTLES INTO THE AREA LATE WEDNESDAY.
COLD HIGH PRESSURE LINGERS THROUGH THURSDAY...THEN THERE ARE
INDICATIONS THAT WE MIGHT BREAK THE COLD AND ACTIVE PATTERN AS UPPER
LEVEL HIGH PRESSURE BUILDS OVER THE WESTERN U.S. AND BEGINS TO PUSH
INTO THE PLAINS.
WILL CERTAINLY NEED TO MONITOR THINGS OVER THE NEXT SEVERAL DAYS.
GENERALLY NEAR TO BELOW ADVISORY CRITERIA SNOWS WITH EACH SYSTEM BUT
SNOW AMOUNTS COULD BEGIN TO ADD UP. WILL ISSUE A SPS TO HIGHLIGHT
THE FIRST SYSTEM AND INDICATE THE POSSIBILITY OF ADDITIONAL SNOWS
EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1148 AM CST FRI JAN 30 2015
ARCTIC COLD FRONT ACROSS SOUTHERN SASKATCHEWAN WILL MOVE SOUTHEAST
INTO NORTH DAKOTA THIS AFTERNOON. COLD HIGH PRESSURE WILL MOVE
SLOWLY SOUTHEAST TONIGHT AND SATURDAY. LOW MVFR TO IFR CONDITIONS
WILL SPREAD FROM NORTHEAST TO SOUTHEAST THIS AFTERNOON INTO
TONIGHT. SNOW WILL SPREAD SOUTHEAST ACROSS WEST AND CENTRAL NORTH
DAKOTA AFTER 06Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...AJ
LONG TERM...TWH
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
851 AM CST FRI JAN 30 2015
.UPDATE...
ISSUED AT 849 AM CST FRI JAN 30 2015
CLOUDS HAVE CLEARED ACROSS THE REGION THIS MORNING IN MODERATE
WARM ADVECTION. MORNING TEMPERATURES ARE IN THE TEENS AND LOWER
20S WHICH IS QUITE MILD FOR THIS TIME OF THE YEAR. UPDATE TO CLOUDS
THE ONLY CHANGE.
UPDATE ISSUED AT 639 AM CST FRI JAN 30 2015
MAINLY CLEAR SKIES ACROSS WESTERN NORTH DAKOTA THIS MORNING. AN
AREA OF MVFR-IFR CLOUDS FROM BOTTINEAU TO HARVEY AND WISHEK WILL
CONTINUE TO MOVE EAST THIS MORNING ON THE BACK SIDE OF HIGH
PRESSURE OVER MINNESOTA AND AHEAD OF AN ADVANCING WARM FRONT
MOVING INTO WESTERN NORTH DAKOTA. MADE SOME MINOR SKY COVER
ADJUSTMENTS BASED ON LATEST SATELLITE AND BUMPED UP SOUTHERLY
WINDS JUST A LITTLE THIS MORNING OVER THE EASTERN FORECAST AREA.
UPDATED TEXT PRODUCTS WILL BE SENT SHORTLY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CST FRI JAN 30 2015
THE MAIN FOCUS FOR THE SHORT TERM IS CLOUDS ACROSS THE JAMES VALLEY
AND AFTERNOON TEMPERATURES.
EARLY THIS MORNING AN AREA OF LOW STRATUS CONTINUES TO DEVELOP
ACROSS THE SOUTHERN JAMES RIVER VALLEY AND PUSH NORTH. THE HRRR IS
DOING A REASONABLE JOB DEPICTING THE CURRENT AREA OF STRATUS IN
THE 925MB MOISTURE FIELD. THE HRRR HAS THE AREA OF STRATUS
LIFTING OFF TO THE NORTHEAST AROUND 8 AM.
TEMPERATURES TODAY WILL BE LARGELY DEPENDENT ON THE PROGRESSION OF
THE WARM AND COLD FRONTS ASSOCIATED WITH A SURFACE LOW...CURRENTLY
CENTERED OVER NORTHEAST MONTANA. MOST OF THE OPERATIONAL MODELS
HAVE THE WARM FRONT THROUGH THE REGION BY ABOUT 11 AM. WINDS THEN SHIFT
FROM THE NORTHWEST AND THE COLD FRONT DIVES SOUTHEAST ACROSS THE
AREA THIS AFTERNOON. IT APPEARS THE SOUTHWEST WILL BE FAVORED FOR
A NICE QUICK WARM UP BEFORE THE COLD FRONT MOVES THROUGH. WITH
PLENTY OF SUNSHINE...WEST DOWNSLOPING WINDS AND A WARM FRONT
NEARBY THE SOUTHWEST SHOULD SEE TEMPERATURES APPROACHING THE LOW
50S. THE NORTH SHOULD REMAIN COOLER AS THE COLD FRONT WILL ENTER
EARLIER AND COLD AIR ADVECTION TAKE HOLD.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 338 AM CST FRI JAN 30 2015
MAIN FORECAST HIGHLIGHTS ARE COLD AND UNSETTLED WEATHER THROUGH AT
LEAST MID WEEK WITH A NUMBER OF LIGHT SNOW EVENTS. THEN POSSIBLY A
RETURN TO MORE MILD CONDITIONS AT THE END OF THE EXTENDED PERIOD.
DETERMINISTIC MODELS ARE IN PRETTY GOOD AGREEMENT EARLY IN PERIOD
AND USED A MODEL BLEND WITH WPC QPF FOR SNOW ACCUMULATIONS.
WITH THE SATURDAY SYSTEM...00 UTC FRIDAY MODELS HAVE FLIPPED A BIT
FROM 24 HOURS AGO. THE GFS/ECMWF ARE NOW FARTHER NORTH AND EAST
WHILE THE GEM HAS SHIFTED FARTHER SOUTHWEST WITH THE HIGHEST QPF.
HOWEVER A BLEND STILL YIELDS A REASONABLE ESTIMATE...CLOSE TO WPC
FORECAST AND SIMILAR TO OUR PREVIOUS FORECAST. SYNOPTIC SCALE UPPER
LEVEL FORCING WILL DEVELOP OVER EASTERN MONTANA AND WESTERN NORTH
DAKOTA SATURDAY...ASSOCIATED WITH A 120KT UPPER LEVEL JET DROPPING
INTO MONTANA FROM BRITISH COLUMBIA. MEANWHILE...SHORTWAVE IMPULSES
MOVING THROUGH THE UPPER FLOW WILL INTERACT WITH A LOW LEVEL
BAROCLINIC ZONE OVER THIS SAME AREA. THIS SHOULD RESULT IN A
WIDESPREAD AREA OF LIGHT SNOW LATE FRIDAY NIGHT THROUGH SATURDAY
NIGHT ACROSS WESTERN AND MOST OF CENTRAL NORTH DAKOTA. HAVE
EXPANDED CATEGORICAL POPS SLIGHTLY FROM PREVIOUS FORECAST. OTHERWISE
THE ONLY CHANGE WAS TO EXPAND CHANCE POPS A LITTLE FARTHER NORTH.
FORECAST SNOW AMOUNTS ARE GENERALLY 1 TO 2.5 INCHES ACROSS MOST OF
THE FORECAST AREA...BUT TAPERING QUICKLY TO LITTLE IF ANY
ACCUMULATION FROM AROUND SHERWOOD TO RUGBY AND CARRINGTON.
ANOTHER UPPER LEVEL IMPULSE TRACKS ACROSS THE FORECAST AREA ON
MONDAY. THERE ARE DETERMINISTIC MODEL DIFFERENCES...BUT IN GENERAL
IT LOOKS LIKE ANOTHER WIDESPREAD AREA OF SNOW...BUT WITH LESSER
AMOUNTS OF AN INCH AND A HALF OR LESS. THIS SYSTEM IS QUICKLY
FOLLOWED BY ANOTHER MORE VIGOROUS SYSTEM ASSOCIATED WITH ANOTHER
STRONG UPPER LEVEL JET TRAVERSING THE ROCKIES WHICH INDUCES SURFACE
LOW PRESSURE OVER THE MONDAY REGION TUESDAY. AGAIN...WIDESPREAD
SNOWS SPREADING ACROSS THE FORECAST AREA...GENERALLY SUB ADVISORY
CATEGORY SNOW. RIGHT NOW IT APPEARS THE SOUTHWEST QUARTER WOULD
RECEIVE THE HIGHEST SNOW AMOUNTS...BUT THIS FAR OUT THINGS CAN
CERTAINLY CHANGE. THIS SYSTEM HAS ALREADY TRENDED FARTHER NORTH AS
PREVIOUS RUNS SUPPRESSED PRECIPITATION FARTHER SOUTH. WILL NEED TO
CONTINUE TO MONITOR THIS SYSTEM.
BEYOND THE TUESDAY SYSTEM...THE GFS/GEM SUPPRESS ADDITIONAL SNOWS
SOUTH OF THE FORECAST AREA AS VERY COLD HIGH PRESSURE DROPS SOUTH
INTO THE NORTHERN PLAINS. THE ECMWF HOWEVER KEEPS A QUASI ZONAL FLOW
OVER THE REGION LONG ENOUGH TO BRING ANOTHER IMPULSE ACROSS THE
FORECAST AREA TUESDAY NIGHT THROUGH WEDNESDAY MORNING...GIVING US
ONE LAST SHOT OF WIDESPREAD LIGHT SNOWS BEFORE COLD HIGH PRESSURE
SETTLES INTO THE AREA LATE WEDNESDAY.
COLD HIGH PRESSURE LINGERS THROUGH THURSDAY...THEN THERE ARE
INDICATIONS THAT WE MIGHT BREAK THE COLD AND ACTIVE PATTERN AS UPPER
LEVEL HIGH PRESSURE BUILDS OVER THE WESTERN U.S. AND BEGINS TO PUSH
INTO THE PLAINS.
WILL CERTAINLY NEED TO MONITOR THINGS OVER THE NEXT SEVERAL DAYS.
GENERALLY NEAR TO BELOW ADVISORY CRITERIA SNOWS WITH EACH SYSTEM BUT
SNOW AMOUNTS COULD BEGIN TO ADD UP. WILL ISSUE A SPS TO HIGHLIGHT
THE FIRST SYSTEM AND INDICATE THE POSSIBILITY OF ADDITIONAL SNOWS
EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 639 AM CST FRI JAN 30 2015
VFR CONDITIONS ARE EXPECTED AT KISN/KMOT/KDIK/KBIS THROUGH THE
TAF PERIOD. KJMS WILL REMAIN MVFR TO IFR THROUGH AROUND 14-15 UTC.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...AJ
LONG TERM...TWH
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS BISMARCK ND
640 AM CST FRI JAN 30 2015
.UPDATE...
ISSUED AT 639 AM CST FRI JAN 30 2015
MAINLY CLEAR SKIES ACROSS WESTERN NORTH DAKOTA THIS MORNING. AN
AREA OF MVFR-IFR CLOUDS FROM BOTTINEAU TO HARVEY AND WISHEK WILL
CONTINUE TO MOVE EAST THIS MORNING ON THE BACK SIDE OF HIGH
PRESSURE OVER MINNESOTA AND AHEAD OF AN ADVANCING WARM FRONT
MOVING INTO WESTERN NORTH DAKOTA. MADE SOME MINOR SKY COVER
ADJUSTMENTS BASED ON LATEST SATELLITE AND BUMPED UP SOUTHERLY
WINDS JUST A LITTLE THIS MORNING OVER THE EASTERN FORECAST AREA.
UPDATED TEXT PRODUCTS WILL BE SENT SHORTLY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CST FRI JAN 30 2015
THE MAIN FOCUS FOR THE SHORT TERM IS CLOUDS ACROSS THE JAMES VALLEY
AND AFTERNOON TEMPERATURES.
EARLY THIS MORNING AN AREA OF LOW STRATUS CONTINUES TO DEVELOP
ACROSS THE SOUTHERN JAMES RIVER VALLEY AND PUSH NORTH. THE HRRR IS
DOING A REASONABLE JOB DEPICTING THE CURRENT AREA OF STRATUS IN
THE 925MB MOISTURE FIELD. THE HRRR HAS THE AREA OF STRATUS
LIFTING OFF TO THE NORTHEAST AROUND 8 AM.
TEMPERATURES TODAY WILL BE LARGELY DEPENDENT ON THE PROGRESSION OF
THE WARM AND COLD FRONTS ASSOCIATED WITH A SURFACE LOW...CURRENTLY
CENTERED OVER NORTHEAST MONTANA. MOST OF THE OPERATIONAL MODELS
HAVE THE WARM FRONT THROUGH THE REGION BY ABOUT 11 AM. WINDS THEN SHIFT
FROM THE NORTHWEST AND THE COLD FRONT DIVES SOUTHEAST ACROSS THE
AREA THIS AFTERNOON. IT APPEARS THE SOUTHWEST WILL BE FAVORED FOR
A NICE QUICK WARM UP BEFORE THE COLD FRONT MOVES THROUGH. WITH
PLENTY OF SUNSHINE...WEST DOWNSLOPING WINDS AND A WARM FRONT
NEARBY THE SOUTHWEST SHOULD SEE TEMPERATURES APPROACHING THE LOW
50S. THE NORTH SHOULD REMAIN COOLER AS THE COLD FRONT WILL ENTER
EARLIER AND COLD AIR ADVECTION TAKE HOLD.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 338 AM CST FRI JAN 30 2015
MAIN FORECAST HIGHLIGHTS ARE COLD AND UNSETTLED WEATHER THROUGH AT
LEAST MID WEEK WITH A NUMBER OF LIGHT SNOW EVENTS. THEN POSSIBLY A
RETURN TO MORE MILD CONDITIONS AT THE END OF THE EXTENDED PERIOD.
DETERMINISTIC MODELS ARE IN PRETTY GOOD AGREEMENT EARLY IN PERIOD
AND USED A MODEL BLEND WITH WPC QPF FOR SNOW ACCUMULATIONS.
WITH THE SATURDAY SYSTEM...00 UTC FRIDAY MODELS HAVE FLIPPED A BIT
FROM 24 HOURS AGO. THE GFS/ECMWF ARE NOW FARTHER NORTH AND EAST
WHILE THE GEM HAS SHIFTED FARTHER SOUTHWEST WITH THE HIGHEST QPF.
HOWEVER A BLEND STILL YIELDS A REASONABLE ESTIMATE...CLOSE TO WPC
FORECAST AND SIMILAR TO OUR PREVIOUS FORECAST. SYNOPTIC SCALE UPPER
LEVEL FORCING WILL DEVELOP OVER EASTERN MONTANA AND WESTERN NORTH
DAKOTA SATURDAY...ASSOCIATED WITH A 120KT UPPER LEVEL JET DROPPING
INTO MONTANA FROM BRITISH COLUMBIA. MEANWHILE...SHORTWAVE IMPULSES
MOVING THROUGH THE UPPER FLOW WILL INTERACT WITH A LOW LEVEL
BAROCLINIC ZONE OVER THIS SAME AREA. THIS SHOULD RESULT IN A
WIDESPREAD AREA OF LIGHT SNOW LATE FRIDAY NIGHT THROUGH SATURDAY
NIGHT ACROSS WESTERN AND MOST OF CENTRAL NORTH DAKOTA. HAVE
EXPANDED CATEGORICAL POPS SLIGHTLY FROM PREVIOUS FORECAST. OTHERWISE
THE ONLY CHANGE WAS TO EXPAND CHANCE POPS A LITTLE FARTHER NORTH.
FORECAST SNOW AMOUNTS ARE GENERALLY 1 TO 2.5 INCHES ACROSS MOST OF
THE FORECAST AREA...BUT TAPERING QUICKLY TO LITTLE IF ANY
ACCUMULATION FROM AROUND SHERWOOD TO RUGBY AND CARRINGTON.
ANOTHER UPPER LEVEL IMPULSE TRACKS ACROSS THE FORECAST AREA ON
MONDAY. THERE ARE DETERMINISTIC MODEL DIFFERENCES...BUT IN GENERAL
IT LOOKS LIKE ANOTHER WIDESPREAD AREA OF SNOW...BUT WITH LESSER
AMOUNTS OF AN INCH AND A HALF OR LESS. THIS SYSTEM IS QUICKLY
FOLLOWED BY ANOTHER MORE VIGOROUS SYSTEM ASSOCIATED WITH ANOTHER
STRONG UPPER LEVEL JET TRAVERSING THE ROCKIES WHICH INDUCES SURFACE
LOW PRESSURE OVER THE MONDAY REGION TUESDAY. AGAIN...WIDESPREAD
SNOWS SPREADING ACROSS THE FORECAST AREA...GENERALLY SUB ADVISORY
CATEGORY SNOW. RIGHT NOW IT APPEARS THE SOUTHWEST QUARTER WOULD
RECEIVE THE HIGHEST SNOW AMOUNTS...BUT THIS FAR OUT THINGS CAN
CERTAINLY CHANGE. THIS SYSTEM HAS ALREADY TRENDED FARTHER NORTH AS
PREVIOUS RUNS SUPPRESSED PRECIPITATION FARTHER SOUTH. WILL NEED TO
CONTINUE TO MONITOR THIS SYSTEM.
BEYOND THE TUESDAY SYSTEM...THE GFS/GEM SUPPRESS ADDITIONAL SNOWS
SOUTH OF THE FORECAST AREA AS VERY COLD HIGH PRESSURE DROPS SOUTH
INTO THE NORTHERN PLAINS. THE ECMWF HOWEVER KEEPS A QUASI ZONAL FLOW
OVER THE REGION LONG ENOUGH TO BRING ANOTHER IMPULSE ACROSS THE
FORECAST AREA TUESDAY NIGHT THROUGH WEDNESDAY MORNING...GIVING US
ONE LAST SHOT OF WIDESPREAD LIGHT SNOWS BEFORE COLD HIGH PRESSURE
SETTLES INTO THE AREA LATE WEDNESDAY.
COLD HIGH PRESSURE LINGERS THROUGH THURSDAY...THEN THERE ARE
INDICATIONS THAT WE MIGHT BREAK THE COLD AND ACTIVE PATTERN AS UPPER
LEVEL HIGH PRESSURE BUILDS OVER THE WESTERN U.S. AND BEGINS TO PUSH
INTO THE PLAINS.
WILL CERTAINLY NEED TO MONITOR THINGS OVER THE NEXT SEVERAL DAYS.
GENERALLY NEAR TO BELOW ADVISORY CRITERIA SNOWS WITH EACH SYSTEM BUT
SNOW AMOUNTS COULD BEGIN TO ADD UP. WILL ISSUE A SPS TO HIGHLIGHT
THE FIRST SYSTEM AND INDICATE THE POSSIBILITY OF ADDITIONAL SNOWS
EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 639 AM CST FRI JAN 30 2015
VFR CONDITIONS ARE EXPECTED AT KISN/KMOT/KDIK/KBIS THROUGH THE
TAF PERIOD. KJMS WILL REMAIN MVFR TO IFR THROUGH AROUND 14-15 UTC.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...AJ
LONG TERM...TWH
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS BISMARCK ND
338 AM CST FRI JAN 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CST FRI JAN 30 2015
THE MAIN FOCUS FOR THE SHORT TERM IS CLOUDS ACROSS THE JAMES VALLEY
AND AFTERNOON TEMPERATURES.
EARLY THIS MORNING AN AREA OF LOW STRATUS CONTINUES TO DEVELOP
ACROSS THE SOUTHERN JAMES RIVER VALLEY AND PUSH NORTH. THE HRRR IS
DOING A REASONABLE JOB DEPICTING THE CURRENT AREA OF STRATUS IN
THE 925MB MOISTURE FIELD. THE HRRR HAS THE AREA OF STRATUS
LIFTING OFF TO THE NORTHEAST AROUND 8 AM.
TEMPERATURES TODAY WILL BE LARGELY DEPENDENT ON THE PROGRESSION OF
THE WARM AND COLD FRONTS ASSOCIATED WITH A SURFACE LOW...CURRENTLY
CENTERED OVER NORTHEAST MONTANA. MOST OF THE OPERATIONAL MODELS
HAVE THE WARM FRONT THROUGH THE REGION BY ABOUT 11 AM. WINDS THEN SHIFT
FROM THE NORTHWEST AND THE COLD FRONT DIVES SOUTHEAST ACROSS THE
AREA THIS AFTERNOON. IT APPEARS THE SOUTHWEST WILL BE FAVORED FOR
A NICE QUICK WARM UP BEFORE THE COLD FRONT MOVES THROUGH. WITH
PLENTY OF SUNSHINE...WEST DOWNSLOPING WINDS AND A WARM FRONT
NEARBY THE SOUTHWEST SHOULD SEE TEMPERATURES APPROACHING THE LOW
50S. THE NORTH SHOULD REMAIN COOLER AS THE COLD FRONT WILL ENTER
EARLIER AND COLD AIR ADVECTION TAKE HOLD.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 338 AM CST FRI JAN 30 2015
MAIN FORECAST HIGHLIGHTS ARE COLD AND UNSETTLED WEATHER THROUGH AT
LEAST MID WEEK WITH A NUMBER OF LIGHT SNOW EVENTS. THEN POSSIBLY A
RETURN TO MORE MILD CONDITIONS AT THE END OF THE EXTENDED PERIOD.
DETERMINISTIC MODELS ARE IN PRETTY GOOD AGREEMENT EARLY IN PERIOD
AND USED A MODEL BLEND WITH WPC QPF FOR SNOW ACCUMULATIONS.
WITH THE SATURDAY SYSTEM...00 UTC FRIDAY MODELS HAVE FLIPPED A BIT
FROM 24 HOURS AGO. THE GFS/ECMWF ARE NOW FARTHER NORTH AND EAST
WHILE THE GEM HAS SHIFTED FARTHER SOUTHWEST WITH THE HIGHEST QPF.
HOWEVER A BLEND STILL YIELDS A REASONABLE ESTIMATE...CLOSE TO WPC
FORECAST AND SIMILAR TO OUR PREVIOUS FORECAST. SYNOPTIC SCALE UPPER
LEVEL FORCING WILL DEVELOP OVER EASTERN MONTANA AND WESTERN NORTH
DAKOTA SATURDAY...ASSOCIATED WITH A 120KT UPPER LEVEL JET DROPPING
INTO MONTANA FROM BRITISH COLUMBIA. MEANWHILE...SHORTWAVE IMPULSES
MOVING THROUGH THE UPPER FLOW WILL INTERACT WITH A LOW LEVEL
BAROCLINIC ZONE OVER THIS SAME AREA. THIS SHOULD RESULT IN A
WIDESPREAD AREA OF LIGHT SNOW LATE FRIDAY NIGHT THROUGH SATURDAY
NIGHT ACROSS WESTERN AND MOST OF CENTRAL NORTH DAKOTA. HAVE
EXPANDED CATEGORICAL POPS SLIGHTLY FROM PREVIOUS FORECAST. OTHERWISE
THE ONLY CHANGE WAS TO EXPAND CHANCE POPS A LITTLE FARTHER NORTH.
FORECAST SNOW AMOUNTS ARE GENERALLY 1 TO 2.5 INCHES ACROSS MOST OF
THE FORECAST AREA...BUT TAPERING QUICKLY TO LITTLE IF ANY
ACCUMULATION FROM AROUND SHERWOOD TO RUGBY AND CARRINGTON.
ANOTHER UPPER LEVEL IMPULSE TRACKS ACROSS THE FORECAST AREA ON
MONDAY. THERE ARE DETERMINISTIC MODEL DIFFERENCES...BUT IN GENERAL
IT LOOKS LIKE ANOTHER WIDESPREAD AREA OF SNOW...BUT WITH LESSER
AMOUNTS OF AN INCH AND A HALF OR LESS. THIS SYSTEM IS QUICKLY
FOLLOWED BY ANOTHER MORE VIGOROUS SYSTEM ASSOCIATED WITH ANOTHER
STRONG UPPER LEVEL JET TRAVERSING THE ROCKIES WHICH INDUCES SURFACE
LOW PRESSURE OVER THE MONDAY REGION TUESDAY. AGAIN...WIDESPREAD
SNOWS SPREADING ACROSS THE FORECAST AREA...GENERALLY SUB ADVISORY
CATEGORY SNOW. RIGHT NOW IT APPEARS THE SOUTHWEST QUARTER WOULD
RECEIVE THE HIGHEST SNOW AMOUNTS...BUT THIS FAR OUT THINGS CAN
CERTAINLY CHANGE. THIS SYSTEM HAS ALREADY TRENDED FARTHER NORTH AS
PREVIOUS RUNS SUPPRESSED PRECIPITATION FARTHER SOUTH. WILL NEED TO
CONTINUE TO MONITOR THIS SYSTEM.
BEYOND THE TUESDAY SYSTEM...THE GFS/GEM SUPPRESS ADDITIONAL SNOWS
SOUTH OF THE FORECAST AREA AS VERY COLD HIGH PRESSURE DROPS SOUTH
INTO THE NORTHERN PLAINS. THE ECMWF HOWEVER KEEPS A QUASI ZONAL FLOW
OVER THE REGION LONG ENOUGH TO BRING ANOTHER IMPULSE ACROSS THE
FORECAST AREA TUESDAY NIGHT THROUGH WEDNESDAY MORNING...GIVING US
ONE LAST SHOT OF WIDESPREAD LIGHT SNOWS BEFORE COLD HIGH PRESSURE
SETTLES INTO THE AREA LATE WEDNESDAY.
COLD HIGH PRESSURE LINGERS THROUGH THURSDAY...THEN THERE ARE
INDICATIONS THAT WE MIGHT BREAK THE COLD AND ACTIVE PATTERN AS UPPER
LEVEL HIGH PRESSURE BUILDS OVER THE WESTERN U.S. AND BEGINS TO PUSH
INTO THE PLAINS.
WILL CERTAINLY NEED TO MONITOR THINGS OVER THE NEXT SEVERAL DAYS.
GENERALLY NEAR TO BELOW ADVISORY CRITERIA SNOWS WITH EACH SYSTEM BUT
SNOW AMOUNTS COULD BEGIN TO ADD UP. WILL ISSUE A SPS TO HIGHLIGHT
THE FIRST SYSTEM AND INDICATE THE POSSIBILITY OF ADDITIONAL SNOWS
EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1230 AM CST FRI JAN 30 2015
VFR CONDITIONS ARE EXPECTED AT KISN/KMOT/KDIK/KBIS THROUGH THE
TAF PERIOD. KJMS WILL REMAIN MVFR THROUGH THE EARLY MORNING HOURS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...TWH
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1012 PM EST SAT JAN 31 2015
.SYNOPSIS...
LOW PRESSURE TRAVELING UP THE OHIO VALLEY WILL BRING WIDESPREAD
SNOW AND RAIN TONIGHT INTO MONDAY. MUCH COLDER AIR WILL ARRIVE MONDAY
NIGHT WITH HIGH PRESSURE MOVING IN FROM THE WEST. SNOW AND RAIN
WILL BE POSSIBLE WEDNESDAY WHEN A DISTURBANCE IS FORECAST TO CROSS
THE GREAT LAKES.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THE FIRST CONCERN FOR THE NEAR TERM OF THE FORECAST WAS TO ADD
SOME MORE SLEET. THIS IS BASED PARTLY ON SEVERAL REPORTS IN
SOUTHEASTERN INDIANA...BUT ALSO BASED ON THE WAY CONDITIONS HAVE
EVOLVED TONIGHT AS EVIDENCED BY OBSERVATIONS. DEWPOINT DEPRESSIONS
ARE STILL RATHER HIGH...WITH WET BULB TEMPERATURES BELOW ZERO. THE
KILN SOUNDING INDICATED QUITE A BIT OF DRY AIR BELOW 900MB...BUT
ALSO INDICATED THAT THE WARM LAYER IN THE LOWEST 2KM WAS SLIGHTLY
WARMER THAN THE CURRENT FORECAST HAD SUGGESTED WAS GOING TO
HAPPEN. WITH A SLIGHTLY WARMER STARTING POINT...THE ZONE OF MIXED
PRECIP AND ICE ACCUMULATIONS HAS BEEN SHIFTED SLIGHTLY NORTHWARD.
HOWEVER...THESE ACCUMULATIONS SHOULD STILL REMAIN FAIRLY
LIGHT. THE SOUTHERN TIER OF THE WINTER WEATHER ADVISORY WILL COVER
THE THREAT NICELY...AND IN FACT...THE FAR SOUTHERN COUNTIES IN THE
ADVISORY MAY NOT GET COLD ENOUGH TO SUPPORT MUCH OF A THREAT FOR
ANY GLAZE ACCUMULATION (PERHAPS JUST SOME SLEET MIXING IN NEAR THE
ONSET OF PRECIPITATION).
BASED ON A FULL ANALYSIS OF 18Z MODEL RUNS...RECENT RAP/HRRR
RUNS...AND THE 00Z NAM...ANOTHER SLIGHT ADJUSTMENT WAS MADE TO THE
OVERALL FORECAST ARRANGEMENT FOR SUNDAY. THERE ARE NO SIGNS AT ALL
OF A REVERSAL OF THE GRADUAL NORTHWARD (WARMER) TREND...AND THE
02Z RAP / 00Z NAM ARE PERHAPS AS FAR NORTH WITH THE WARM AIR AS
ANY MODEL HAS BEEN THROUGH THE FORECAST OF THIS EVENT. IT IS STILL
VERY CLEAR THAT ANY LOCATION THAT REMAINS PURELY SNOW WILL RECEIVE
A VERY LARGE AMOUNT (AROUND A FOOT)...BUT THE TRANSITION ZONE
SEEMS TO BE CREEPING NORTHWARD WITH EACH NEW MODEL CYCLE.
THUS...WHILE SNOW TOTALS IN THE FAR NORTHERN CWA (MERCER THROUGH
HARDIN) REMAIN AS HIGH AS BEFORE (UP TO 12 INCHES)...A MODEST
DOWNWARD ADJUSTMENT WAS MADE FURTHER SOUTH. THE NEW WSW PRODUCT
ACCOUNTS FOR THIS CHANGE WITH SOME REFINED AND SLIGHTLY LOWER
NUMBERS FOR SOME OF THE COUNTY SEGMENTS. HOWEVER...IT WOULD BE
PREFERRED TO SEE THE ENTIRE 00Z MODEL SUITE BEFORE MAKING A MORE
SUBSTANTIAL CHANGE (AS WOULD BE SUGGESTED BY THE LATEST MODELS).
PREVIOUS DISCUSSION >
SURFACE LOW PRESSURE WILL DEVELOP OVER THE GREAT PLAINS TONIGHT IN
RESPONSE TO A DIGGING 500 MB TROUGH OVER THE ROCKIES. WHILE JET
STREAM ENERGY INCREASES AS IT ROUNDS THE BASE OF THE UPPER
TROUGH...THE SURFACE LOW WILL DEEPEN...AND THE PRESSURE GRADIENT
WILL TIGHTEN...INCREASING MOISTURE ADVECTION TOWARD THE OHIO
VALLEY.
DURING THIS PROCESS...A BAND OF ISENTROPIC LIFT WILL SET UP OVER
THE ILN AREA WELL AHEAD OF THE SURFACE LOW TO THE WEST. LATEST
MODELS SHOW THE BAND AFFECTING LOCATIONS MAINLY NORTH OF
CINCINNATI. PRECIP WILL START AROUND MIDNIGHT...WITH TYPE VARYING
WITH RESPECT TO ATMOSPHERIC TEMPERATURE PROFILES. EXPECT DEFINITE SNOW
FOR THE NORTH HALF OF THE FA INCLUDING DAYTON...COLUMBUS AND
WAPAKONETA. FOR LOCATIONS ROUGHLY NEAR WILMINGTON...WARMER AIR
ALOFT SHOULD ALLOW A WINTRY MIX. FARTHER SOUTH FROM CINCINNATI TO
PORTSMOUTH AND ACROSS NORTHERN KENTUCKY...THERE WILL BE A CHANCE
FOR A LIGHT WINTRY MIX OF FZRA AND RA.
DUE TO THE SIGNIFICANT NATURE OF SNOW ACCUMULATIONS BASED ON
QPF AND MODEL SOUNDINGS...WENT WITH A WINTER STORM WARNING FOR
SNOW NORTH OF DAY AND CMH. FARTHER SOUTH WENT WITH A WINTER
WEATHER ADVISORIES FOR LIGHTER SNOW AND ICE ACCUMULATIONS. SEE
CLEWSWILN FOR FURTHER DETAILS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
SURFACE LOW WILL PROGRESS UP THE OHIO VALLEY TO SOUTHERN INDIANA ON
SUNDAY. WHILE SNOW PERSISTS NORTH OF DAYTON...CONTINUED MOISTURE
ADVECTION ALONG THE WARM CONVEYOR BELT AHEAD OF THE LOW WILL ALLOW
PRECIP TO OVERSPREAD THE AREA BY SUNDAY EVENING. WITH MODELS
PRESENTING A WARMER SOLUTION...RAIN IS THE ANTICIPATED PRECIP TYPE
SOUTH OF I-70...WITH SNOW NORTH. A BAND OF FRONTOGENETIC FORCING
WILL ENHANCE PRECIP ESPECIALLY ACROSS THE NORTH WHERE SIGNIFICANT
SNOW WILL ACCUMULATE.
THE SURFACE LOW WILL BE MOVING FROM EASTERN OHIO TO PENNSYLVANIA
BY MONDAY MORNING. PRECIP WILL TRANSITION TO ALL SNOW AREA WIDE
BEFORE DIMINISHING IN COLD ADVECTION BEHIND THE DEPARTING LOW.
SNOW IN THE NORTH WILL BE ENHANCED BY STRONG DEFORMATION IN THE NW
QUADRANT OF THE LOW. TOTAL SNOW AMOUNTS WILL VARY GREATLY...WITH
OVER 10 INCHES POSSIBLE OVER WEST CENTRAL OHIO...A FEW INCHES NEAR
DAYTON AND COLUMBUS...AND UNDER AN INCH AT CINCINNATI...PORTSMOUTH
AND NORTHERN KENTUCKY.
COLD TEMPERATURES AND WIND CHILLS ARE IN STORE FOR MONDAY AND
MONDAY NIGHT. HIGHS IN THE TEENS AN 20S MONDAY WILL BE FOLLOWED BY
LOWS RANGING FROM THE NEGATIVE SINGLE DIGITS NORTH TO THE MID
TEENS SOUTH MONDAY NIGHT. THE COLD TEMPS WILL COMBINE WITH BRISK
WINDS TO PRODUCE WIND CHILLS BELOW MINUS 10 OVER THE NORTH HALF OF
THE FA. WILL MENTION WIND CHILLS IN HWO FOR NOW...AND A WIND CHILL
ADVISORY MAY EVENTUALLY BE ISSUED ACROSS THE NORTH.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
NORTHWEST MID/UPPER LEVEL FLOW WITH THE CENTER OF SPRAWLING SURFACE
HIGH PRESSURE SLIDING OFF TO THE EAST COAST BY TUESDAY EVENING. THIS
HIGH WILL PROVIDE COLD AND DRY WEATHER CONDITIONS. AFTER A COLD
START TO THE DAY...TEMPERATURES WILL WARM TO HIGHS 5 TO 10 DEGREES
BELOW NORMAL. TUESDAYS HIGHS TO RANGE FROM THE MID 20S NE TO THE
UPPER 30S SW.
FLOW BACKS WESTERLY A HEAD OF DIGGING TROF OVER THE GREAT LAKES...
WITH A QUICK MORNING SYSTEM MOVING THRU THE REGION TUESDAY
NIGHT/WED. WILL HAVE CHANCE POPS FOR THIS PERIOD WITH THE BEST
CHANCE ACRS THE NORTH. PCPN WILL LKLY MIX WITH AND CHANGE TO RAIN
IN THE SOUTH PRIOR TO COLD FRONTAL PASSAGE WED AFTN. LOWS TUESDAY
NIGHT TO RANGE FROM THE LOWER 20S NE TO THE UPPER 20S SW. HIGHS ON
WED FROM THE LOWER 30S NORTH TO THE LOWER/MID 40S FAR SOUTH.
REINFORCING SHOT OF COLD AIR WITH HIGH PRESSURE OF CANADIAN ORIGIN
TO BUILD SE BECOMING CENTERED OVER OHIO THURSDAY. COLD AND DRY
WEATHER ON TAP WITH WED NIGHT/S LOWS FROM THE SINGLE DIGITS ACRS THE
NORTHWEST WHERE SNOW PACK WILL EXIST TO NEAR 20 SE. HIGHS ON THURSDAY
TO BE AROUND 15 DEGREES BELOW NORMAL...RANGING FROM THE UPPER TEENS
NW TO THE UPPER 20S SE.
THIS SFC HIGH BUILDS SLOWLY EAST TO THE EAST COAST BY THE END OF THE
WEEK. COLD TEMPERATURES TO CONTINUE WITH LOWS THURSDAY NIGHT FROM
THE SINGLE DIGITS BELOW ZERO NW TO NEAR 10 SE.
AS THE HIGH MOVES OFF TO THE EAST A RETURN FLOW DEVELOPS WITH SOME
SOME MODERATION TO TEMPERATURES INTO THE WEEKEND. HIGHS ON FRIDAY
FROM NEAR 20 NORTH TO THE LOWER 30S FAR SOUTH AND WARMING ON
SATURDAY FROM THE UPPER 20S NORTH TO AROUND 40 SOUTH. MODEL SOLN
SPREAD LARGE NEXT SATURDAY REGARDING TIMING AND PLACEMENT OF NEXT
SYSTEM. HAVE KEPT FCST DRY THRU SAT AFTN ATTM MORE LIKE THE GFS SOLN
BUT THIS MAY CHANGE WITH LATER UPDATES.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
AN INITIAL ROUND OF PRECIPITATION IS EXPECTED TO BEGIN AT THE TAF
SITES IN THE NEXT FEW HOURS. A MIX OF PRECIPITATION TYPES WILL BE
POSSIBLE...WITH RAIN MOST LIKELY FOR CINCINNATI...AND SNOW MOST
LIKELY FOR DAYTON AND COLUMBUS. HOWEVER...THERE COULD BE A BRIEF
MIX WITH FREEZING RAIN OR SLEET AT ANY OF THE LOCATIONS. IFR
CONDITIONS ARE EXPECTED IN THE HEAVIER PRECIPITATION FOR DAYTON
AND COLUMBUS.
THERE WILL BE SOMEWHAT OF A LULL IN ACTIVITY ON SUNDAY
MORNING...THOUGH CEILINGS AND VISIBILITIES MAY REMAIN IN THE MVFR
RANGE. BY AFTERNOON...A MORE SIGNIFICANT AREA OF PRECIPITATION
WILL SPREAD INTO THE REGION. THIS PRECIPITATION IS EXPECTED TO BE
RAIN FOR CINCINNATI...WITH A MIX OF RAIN AND SNOW FOR COLUMBUS AND
DAYTON. CEILINGS AND VISIBILITIES WILL ALMOST CERTAINLY DROP TO
THE IFR RANGE FOR A LENGTHY PERIOD OF TIME...PERSISTING BEYOND THE
END OF THE TAF PERIOD INTO SUNDAY NIGHT.
OUTLOOK...IFR CEILINGS AND VISIBILITIES WILL OCCUR SUNDAY NIGHT
IN RAIN CHANGING TO SNOW. MVFR CEILINGS ARE EXPECTED TO CONTINUE
INTO MONDAY. MVFR CEILINGS ARE POSSIBLE TUESDAY NIGHT INTO
WEDNESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY UNTIL 9 AM EST SUNDAY FOR OHZ063>065-
070>074-077>080-082.
WINTER STORM WARNING UNTIL 7 AM EST MONDAY FOR OHZ026-034-035-
042>046-051-052.
WINTER WEATHER ADVISORY UNTIL 7 AM EST MONDAY FOR OHZ053>056-
060>062.
KY...WINTER WEATHER ADVISORY UNTIL 9 AM EST SUNDAY FOR KYZ089>093.
IN...WINTER WEATHER ADVISORY UNTIL 9 AM EST SUNDAY FOR INZ058-059-
066-073>075-080.
WINTER WEATHER ADVISORY UNTIL 7 AM EST MONDAY FOR INZ050.
&&
$$
SYNOPSIS...CONIGLIO
NEAR TERM...CONIGLIO/HATZOS
SHORT TERM...CONIGLIO
LONG TERM...AR
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
436 PM EST FRI JAN 30 2015
.SYNOPSIS...
ARCTIC AIR WILL BRING BITTER COLD TEMPERATURES AND SUBZERO WIND
CHILLS TO MUCH OF CENTRAL PENNSYLVANIA TONIGHT INTO EARLY SATURDAY.
CONFIDENCE IS INCREASING FOR A HIGH IMPACT WINTER WEATHER EVENT
SUNDAY INTO MONDAY WITH THE POTENTIAL FOR SIGNIFICANT SNOW
ACCUMULATION AND SOME MIXED WINTRY PRECIPITATION. ANOTHER SHOT
OF VERY COLD ARCTIC AIR SHOULD FOLLOW FOR TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
THE COLD FRONT HAS CLEARED THE EASTERN ZONES AND ARCTIC AIR IS
BEGINNING TO FILTER INTO THE REGION. THE RAP SHOWS THE CORE OF LOW
LEVEL COLD AIR ENTERING WESTERN PA SO TEMPS WHICH ARE STILL
RELATIVELY MILD OVER ABOUT THE EASTERN 1/2 OR SO OF MY FCST
AREA...WILL LEVEL OFF AND EVEN BEGIN FALLING SOON.
THE REMAINDER OF TODAY WILL BE BLUSTERY AND TURNING COLDER. MOST
OF THE LINGERING SNOW SHOWERS WILL FAVOR THE USUAL WESTERN AND
NORTHERN HIGHER TERRAIN...WITH CENTRAL AND EASTERN AREAS SEEING
JUST A SMALL CHANCE OF A BRIEF SNOW SHOWER OR PASSING FLURRY.
WIND CHILLS WILL RANGE FROM 5 TO 15 BELOW ZERO OVER WESTERN
HIGHER ELEVATIONS BY LATE IN THE DAY IN THE GUSTY WINDS BEHIND
THE DEPARTING FRONT.
SKIES WILL CLEAR ACROSS MOST OF THE REGION OVERNIGHT. WESTERN
UPSLOPE AREAS AND MY FAR NORTHEASTERN ZONES MAY KEEP CLOUDS AND
LINGERING FLURRIES THE LONGEST...BUT FORECAST SOUNDINGS SHOW THE
INVERSION HEIGHTS COMING DOWN SO THE CHANCES FOR ACTUAL
MEASURABLE SNOW WILL BE DWINDLING QUICKLY. WINDS REMAINING IN THE
10-15 MPH RANGE...WITH HIGHER GUSTS WILL KEEP WIND CHILLS IN THE
10-20 BELOW ZERO RANGE OVER MUCH OF THE REGION.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
SATURDAY WILL START BRIGHT IN MOST AREAS AS THE HIGH CRESTS JUST
TO OUR SOUTH. HIGH CLOUDS MAY BEGIN TO INVADE FOR THE LAST HALF OF
THE AFTERNOON...BUT THEY SHOULD DO LITTLE TO MAR AN OTHERWISE FAIR
ALBEIT COLD MID WINTER`S DAY.
HIGHS FROM THE MID TEENS TO MID 20S NORTH TO SOUTH WILL BE ABOUT
15 DEG BELOW NORMAL ON AVERAGE.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
*SIGNIFICANT WINTER WEATHER/SNOW EVENT POSSIBLE SUNDAY-MONDAY
*BITTER COLD TEMPERATURES AND DANGEROUS WIND CHILLS POSSIBLE
MONDAY NIGHT INTO TUESDAY
A POTENTIALLY WIDESPREAD HIGH IMPACT WINTER WX EVENT APPEARS TO
BE SHAPING UP ACROSS CENTRAL PENNSYLVANIA FOR SUNDAY INTO MONDAY.
A WINTER STORM WATCH HAS BEEN ISSUED FOR ALL CENTRAL PA COUNTIES
AND IS VALID FROM 12PM SUNDAY THROUGH 12 PM MONDAY. CONFIDENCE IN
THE EVENT OCCURRING IS AVERAGE WITH SLIGHTLY LOWER CONFIDENCE IN
THE DETAILS SUCH AS LOCATION AND SNOW ACCUM NUMBERS GIVEN THE
UNCERTAINTY IN THE TRACK OF THE SYSTEM...AND POTENTIAL FOR MIXED
PCPN/WARMER TEMPS IN THE SRN 1/3 OF THE AREA.
A SHORTWAVE NOW ENTERING CENTRAL BRITISH COLUMBIA WILL BE DIGGING
SOUTHEAST DOWN INTO THE NORTHERN/CENTRAL PLAINS LATER SAT AND INTO
SUN. THIS ENERGY COUPLED WITH A MORE SUBTLE SHORTWAVE ON ITS HEELS
DROPPING DOWN FROM THE NORTHWEST TERRITORIES WILL PLAY A KEY ROLE
IN THE EVOLUTION OF SURFACE LOW PRESSURE THAT IS CURRENTLY
FORECAST TO DEVELOP OVER THE LOWER MO AND MID MS VALLEY REGION BY
EARLY SUN BEFORE THEN AIMING EAST TOWARD THE OH VALLEY AND MID-
ATLANTIC STATES SUN NIGHT AND MON. AS THIS STORM DEVELOPS...MUCH
COLDER AIR WILL BUILD NOT ONLY BEHIND THE SYSTEM AS A LARGE ARCTIC
ANTICYCLONE HEADS SOUTHWARD INTO THE NORTHERN PLAINS...BUT COLDER
AIR WILL ALSO BLEED EASTWARD AS PRESSURES RISE OVER SOUTHEASTERN
CANADA AND NORTHERN NEW ENGLAND IN ASSOCIATION WITH A PRONOUNCED
UPPER CONFLUENCE ZONE. THE COMBINATION OF THESE TWO SYSTEMS WILL
HELP GENERATE A INCREASINGLY TIGHT BAROCLINIC ZONE UPON WHICH THE
DEVELOPING SURFACE LOW WILL MOVE ALONG.
THE PREVAILING SHIFT IN THE 12Z MODELS WAS TO CONTINUE A MORE
NORTHERLY TRACK WITH THIS SYSTEM...WHICH IS REFLECTED IN THE WPC
FORECAST WHICH WAS WEIGHTED HEAVILY IN THE FINAL GRIDDED SNOW/ICE
ACCUMULATIONS. HOWEVER FORECAST CONFIDENCE IS TEMPERED BY THE RUN-
TO- RUN INCONSISTENCIES THE MODELS HAVE SHOWN ALONG THE WITH
DISTINCT POSSIBILITY THAT THE MODELS MAY REVERSE TRENDS IN
SUBSEQUENT RUNS. WITH SEVERAL FORECAST CYCLES COMING UP ANTICIPATE
SOME CHANGES REGARDING NUMBERS AND LOCATIONS OF SNOWFALL TOTALS.
A SHOT OF ARCTIC AIR IS FORECAST TO SURGE INTO THE AREA BEHIND THE
EARLY WEEK STORM WITH POTENTIAL FOR DANGEROUS WIND CHILLS MONDAY
NIGHT INTO TUESDAY. THIS COULD ADD TO STORM-RELATED IMPACTS. HIGH
PRESSURE SHOULD BRING COLD BUT QUIET WEATHER INTO MIDWEEK. MODELS
AND ENSEMBLES SHOW A COASTAL TYPE SYSTEM SOMETIME NEXT WED-FRI BUT
IT IS WAY TOO EARLY TO SPECULATE ON THIS SYSTEM.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
PREDOMINANTLY IFR AT BFD AND JST WILL CONTINUE INTO THE AFTERNOON
AS POST FRONTAL SNOW SHOWERS CONTINUE TO FAVOR THE HIGH TERRAIN
TERMINALS OF THE WEST AND NORTH. THROUGH THE CENTRAL AREAS THE
CONDITIONS WILL SLOWLY IMPROVE AS THE DAY CONTINUES BEFORE
BECOMING VFR BY MID TO LATE AFTERNOON. EASTERN AND SOUTHEASTERN
TERMINALS WILL BE MAINLY VFR WITH PERHAPS A BRIEF REDUCTION IN A
PASSING SNOW SHOWER.
GUSTY WINDS WILL CONTINUE INTO THE OVERNIGHT BUT DIMINISHING
SOMEWHAT TO BETWEEN 15-20KT.
OUTLOOK...
SAT...VFR.
SUN...WIDESPREAD IFR/MVFR DEVELOPING ASSOCIATED WITH A STORM
MOVING TOWARD THE REGION.
MON...REDUCED CONDS EARLY...IMPROVING AS THE STORM MOVES AWAY FROM
THE AREA.
TUE-WED...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY
MORNING FOR PAZ004>006-010>012-017>019-024>028-033>037-041-042-
045-046-049>053-056>059-063>066.
WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR PAZ004>006-010>012-017>019-024-033-037-041-042-
045-046-049-051>053-058.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...STEINBUGL
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
206 PM EST FRI JAN 30 2015
.SYNOPSIS...
ARCTIC AIR WILL CONTINUE TO POUR INTO THE REGION IN THE WAKE OF
OUR DEPARTING COLD FRONT. HIGH PRESSURE WILL TRACK OVERHEAD
TONIGHT AND SOUTHEAST OF THE REGION LATER SATURDAY INTO SUNDAY. A
NEW STORM SYSTEM WILL BRING THE THREAT FOR MORE WINTRY
PRECIPITATION TO THE REGION SUNDAY AND MONDAY. ANOTHER SURGE OF
COLD AIR WILL FOLLOW INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE COLD FRONT HAS CLEARED THE EASTERN ZONES AND ARCTIC AIR IS
BEGINNING TO FILTER INTO THE REGION. THE RAP SHOWS THE CORE OF LOW
LEVEL COLD AIR ENTERING WESTERN PA SO TEMPS WHICH ARE STILL
RELATIVELY MILD OVER ABOUT THE EASTERN 1/2 OR SO OF MY FCST
AREA...WILL LEVEL OFF AND EVEN BEGIN FALLING SOON.
THE REMAINDER OF TODAY WILL BE BLUSTERY AND TURNING COLDER. MOST
OF THE LINGERING SNOW SHOWERS WILL FAVOR THE USUAL WESTERN AND
NORTHERN HIGHER TERRAIN...WITH CENTRAL AND EASTERN AREAS SEEING
JUST A SMALL CHANCE OF A BRIEF SNOW SHOWER OR PASSING FLURRY.
WIND CHILLS WILL RANGE FROM 5 TO 15 BELOW ZERO OVER WESTERN
HIGHER ELEVATIONS BY LATE IN THE DAY IN THE GUSTY WINDS BEHIND
THE DEPARTING FRONT.
SKIES WILL CLEAR ACROSS MOST OF THE REGION OVERNIGHT. WESTERN
UPSLOPE AREAS AND MY FAR NORTHEASTERN ZONES MAY KEEP CLOUDS AND
LINGERING FLURRIES THE LONGEST...BUT FORECAST SOUNDINGS SHOW THE
INVERSION HEIGHTS COMING DOWN SO THE CHANCES FOR ACTUAL
MEASURABLE SNOW WILL BE DWINDLING QUICKLY. WINDS REMAINING IN THE
10-15 MPH RANGE...WITH HIGHER GUSTS WILL KEEP WIND CHILLS IN THE
10-20 BELOW ZERO RANGE OVER MUCH OF THE REGION.
&&
.SHORT TERM /SATURDAY/...
SATURDAY WILL START BRIGHT IN MOST AREAS AS THE HIGH CRESTS JUST
TO OUR SOUTH. HIGH CLOUDS MAY BEGIN TO INVADE FOR THE LAST HALF OF
THE AFTERNOON...BUT THEY SHOULD DO LITTLE TO MAR AN OTHERWISE FAIR
ALBEIT COLD MID WINTER`S DAY.
HIGHS FROM THE MID TEENS TO MID 20S NORTH TO SOUTH WILL BE ABOUT
15 DEG BELOW NORMAL ON AVERAGE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
SOME CHC OF SOME LIGHT SNOW SATURDAY NIGHT AND EARLY SUNDAY
ACROSS THE FAR NORTH...WITH COLD FRONT DROPPING SE. HAVE LOW CHC
IN EARLY SUNDAY ACROSS THE FAR WEST.
CONSENSUS BUILDING FOR A MODERATE SNOWSTORM TO AFFECT MUCH OF
CENTRAL PA SUNDAY AFTERNOON THROUGH MONDAY MORNING. TOUCHED UP QPF
AND SNOWFALL GRIDS FOR THAT TIMEFRAME...INDICATING AT LEAST
ADVISORY CRITERIA SNOWFALL. CONSENSUS OF 00Z MODEL SUITE IS FOR
CENTRAL PA TO BE IN THE SWEET SPOT...AND IT APPEARS THAT WARNING
CRITERIA SNOWFALL IS AN INCREASING THREAT GIVEN LATEST GUIDANCE
TRENDS. STILL TOO EARLY FOR HEADLINE ISSUANCES FOR FOR A 5TH
PERIOD AND BEYOND EVENT.
ANOTHER SHOT OF COLD AIR IN FOR MONDAY NIGHT INTO TUE...AS
HIGH PRESSURE BUILDS IN FROM THE PLAINS.
MODELS HINT AT ANOTHER LOW TRACKING NEAR THE AREA ON WED.
HAVE LOW END POPS FOR SNOW. MORE COLD AIR BEHIND THAT SYSTEM.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
PREDOMINANTLY IFR AT BFD AND JST WILL CONTINUE INTO THE AFTERNOON
AS POST FRONTAL SNOW SHOWERS CONTINUE TO FAVOR THE HIGH TERRAIN
TERMINALS OF THE WEST AND NORTH. THROUGH THE CENTRAL AREAS THE
CONDITIONS WILL SLOWLY IMPROVE AS THE DAY CONTINUES BEFORE
BECOMING VFR BY MID TO LATE AFTERNOON. EASTERN AND SOUTHEASTERN
TERMINALS WILL BE MAINLY VFR WITH PERHAPS A BRIEF REDUCTION IN A
PASSING SNOW SHOWER.
GUSTY WINDS WILL CONTINUE INTO THE OVERNIGHT BUT DIMINISHING
SOMEWHAT TO BETWEEN 15-20KT.
OUTLOOK...
SAT...VFR.
SUN...WIDESPREAD IFR/MVFR DEVELOPING ASSOCIATED WITH A STORM
MOVING TOWARD THE REGION.
MON...REDUCED CONDS EARLY...IMPROVING AS THE STORM MOVES AWAY FROM
THE AREA.
TUE-WED...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR PAZ004>006-010>012-017>019-024-033-037-041-042-
045-046-049-051>053-058.
WIND ADVISORY UNTIL 7 AM EST SATURDAY FOR PAZ064>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...DEVOIR/MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1133 AM EST FRI JAN 30 2015
.SYNOPSIS...
A NEW ARCTIC AIRMASS WILL CONTINUE TO POUR INTO THE REGION IN THE
WAKE OF OUR DEPARTING COLD FRONT. HIGH PRESSURE WILL TRACK EAST OF
THE REGION LATER SATURDAY INTO SUNDAY...AND A STORM SYSTEM WILL
SPREAD SNOW INTO THE REGION SUNDAY AND MONDAY. ANOTHER SURGE OF
COLD AIR WILL FOLLOW INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE COLD FRONT HAS CLEARED THE EASTERN ZONES AND ARCTIC AIR IS
BEGINNING TO FILTER INTO THE REGION. THE RAP SHOWS THE CORE OF LOW
LEVEL COLD AIR ENTERING WESTERN PA SO TEMPS WHICH ARE STILL
RELATIVELY MILD OVER ABOUT THE EASTERN 1/2 OR SO OF MY FCST
AREA...WILL LEVEL OFF AND EVEN BEGIN FALLING OVER THE NEXT SEVERAL
HOURS.
THE REMAINDER OF TODAY WILL BE BLUSTERY AND COLDER DAY AS ARCTIC
AIR SPILLS INTO THE REGION. MOST OF THE LINGERING SNOW SHOWERS
WILL FAVOR THE USUAL WESTERN AND NORTHERN HIGHER TERRAIN...WITH
CENTRAL AND EASTERN AREAS SEEING JUST A SMALL CHANCE OF A BRIEF
SNOW SHOWER OR PASSING FLURRY.
WIND CHILLS WILL RANGE FROM 5 TO 15 BELOW ZERO OVER WESTERN
HIGHER ELEVATIONS BY LATE IN THE DAY IN THE GUSTY WINDS BEHIND
THE DEPARTING FRONT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
COLLABORATED A MARGINAL WIND ADVISORY FOR THE LOWER SUSQ
(ADAMS...LANCASTER AND YORK COUNTIES) FOR LATE TODAY THROUGH EARLY
SAT MORNING...MAINLY FOR HIGHER ELEVATION WIND GUST POTENTIAL. OF
MORE SIGNIFICANCE ARE WIND CHILLS DROPPING TO 10 TO 20 BELOW ZERO
TONIGHT THROUGH SATURDAY MORNING TO THE WEST AND NORTH.
WITH HIGH PRESSURE BUILDING...SATURDAY LOOKS SUNNY BUT ON THE
COLD SIDE. WINDS WILL HAVE DECREASED BY EARLY TO MID MORNING.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
SOME CHC OF SOME LIGHT SNOW SATURDAY NIGHT AND EARLY SUNDAY
ACROSS THE FAR NORTH...WITH COLD FRONT DROPPING SE. HAVE LOW CHC
IN EARLY SUNDAY ACROSS THE FAR WEST.
CONSENSUS BUILDING FOR A MODERATE SNOWSTORM TO AFFECT MUCH OF
CENTRAL PA SUNDAY AFTERNOON THROUGH MONDAY MORNING. TOUCHED UP QPF
AND SNOWFALL GRIDS FOR THAT TIMEFRAME...INDICATING AT LEAST
ADVISORY CRITERIA SNOWFALL. CONSENSUS OF 00Z MODEL SUITE IS FOR
CENTRAL PA TO BE IN THE SWEET SPOT...AND IT APPEARS THAT WARNING
CRITERIA SNOWFALL IS AN INCREASING THREAT GIVEN LATEST GUIDANCE
TRENDS. STILL TOO EARLY FOR HEADLINE ISSUANCES FOR FOR A 5TH
PERIOD AND BEYOND EVENT.
ANOTHER SHOT OF COLD AIR IN FOR MONDAY NIGHT INTO TUE...AS
HIGH PRESSURE BUILDS IN FROM THE PLAINS.
MODELS HINT AT ANOTHER LOW TRACKING NEAR THE AREA ON WED.
HAVE LOW END POPS FOR SNOW. MORE COLD AIR BEHIND THAT SYSTEM.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
PREDOMINANTLY IFR AT BFD AND JST WILL CONTINUE INTO THE AFTERNOON
AS POST FRONTAL SNOW BANDS CONTINUE TO FAVOR THE HIGH TERRAIN
TERMINALS OF THE WEST AND NORTH. THROUGH THE CENTRAL AREAS THE
CONDITIONS WILL SLOWLY IMPROVE AS THE DAY CONTINUES BEFORE
BECOMING VFR BY MID TO LATE AFTERNOON. EASTERN AND SOUTHEASTERN
TERMINALS WILL BE MAINLY VFR WITH PERHAPS A BRIEF REDUCTION IN A
PASSING SNOW SHOWER.
GUSTY WINDS WILL CONTINUE INTO THE EVENING...BEFORE WEAKENING
AFTER DARK.
OUTLOOK...
SAT...VFR.
SUN...WIDESPREAD IFR/MVFR DEVELOPING ASSOCIATED WITH A STORM
MOVING TOWARD THE REGION.
MON...REDUCED CONDS EARLY...IMPROVING AS THE STORM MOVES AWAY FROM
THE AREA.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 7 PM THIS EVENING TO 11 AM EST
SATURDAY FOR PAZ004>006-010>012-017>019-024-033-037-041-042-
045-046-049-051>053-058.
WIND ADVISORY FROM 3 PM THIS AFTERNOON TO 7 AM EST SATURDAY
FOR PAZ064>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...DEVOIR/LA CORTE
SHORT TERM...DEVOIR/FITZGERALD/LA CORTE
LONG TERM...DEVOIR/MARTIN
AVIATION...CERU/GARTNER
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
917 PM CST SAT JAN 31 2015
.UPDATE...
Updated the grids and zones to go with chance POPS across the entire
area tonight. Also, a few thunderstorms are possible across the
Northern Edwards Plateau.
&&
.PREV DISCUSSION... /ISSUED 638 PM CST Sat Jan 31 2015/
AVIATION...
/00Z TAFS/
Ceilings remain below 1500 ft across most of West Central TX, with
many forecast terminals experiencing IFR (or worse) conditions.
The primary rain shield has moved east of the forecast area.
However, isentropic ascent will ramp up overnight, resulting in
lowering ceilings and potential light precipitation, mainly in the
form of drizzle. This will knock cloud bases down to generally
700 ft or lower and should cause prevailing visibilities to drop
to 5 miles or less. Some locations may experience more significant
reductions in visibility. Expect poor flight conditions overnight
but winds will veer to the southwest overnight ahead of a cold
front. This front will move through the Big Country mid/late
morning, bringing drier air into the area and eroding the low
clouds from north to south throughout the day. Gusty north winds
will prevail in the wake of this front.
Johnson
&&
.PREV DISCUSSION... /ISSUED 351 PM CST SAT JAN 31 2015/
SHORT TERM...
(Tonight and Sunday )
Light rain was moving north of I-20, and east of an Abilene...
Brady...Mason line at 3 PM. An upper low was west of El Paso,
moving slowly southeast.
Rain was pushing east and ending of West Central, faster than the
models indicated. Indeed at the current pace, nearly all the
present rain at 3 PM will be east or north of West Central Texas
by 6 PM. Kept a chance of showers going overnight, however, with
the El Paso low sending weak disturbances eastward. Additional
rainfall amounts will be light...ranging from a trace to a few
hundredths inch. The NAM and EC models bring isolated to scattered
light showers over West Central Texas tonight. The GFS model`s
convective algorithm is dry. The short range HRRR model brings in
scattered showers, mainly over Crockett county, the Concho Valley
and areas southward. Timing was between 9 PM and 4 AM. This may
actually be the best model as it seems to latched on an area of
lift in the water vapor loop south of El Paso.
A cold front will move through West Central Texas Sunday bringing
gusty north winds by noon. This clear low level moisture and
clouds. Sunshine in the afternoon should allow afternoon highs to
be a 2-4 degrees warmer than today`s, despite cold air advection.
LONG TERM...
(Sunday night through next Saturday)
Warmer weather will make a return to West Central Texas for the
first half of the week. An area of high pressure centered over the
region on Monday, will slide off to our east by mid-week. A
thermal ridge at 850 mb will expand east over the area, allowing
high temperatures to climb from the mid 50s on Monday, to the mid
60s by Wednesday. A weak cold front approaching the area from the
north Wednesday night, will wash out near Interstate 10 during the
day Thursday, bringing cooler/drier air to the region. However,
this will be short-lived, as a lee trough develops to our west on
Friday. With a return flow developing, warmer temperatures and
increasing moisture are expected.
Precipitation chances may also increase for the southern half of
the forecast area. An upper-level disturbance currently located
over Baja California, is expected to pass by to our southeast
Tuesday night/Wednesday morning. This system may bring a chance of
rain to the region, mainly south of a line from San Angelo to
Brownwood. This afternoon`s numerical models have once again
shifted the track of the disturbance farther south and east,
reducing forecast confidence. However, the models have been flip-
flopping on the track for the last few model runs, and considering
the system is still largely in a data-void region, this will
likely continue through the next 48 hours. By then, the system
will enter an improving observational/upper-air network, which may
result in improved model continuity. Given the concerns mentioned
above, only minimal changes were made to the rainfall forecast for
the middle of the week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 49 51 24 51 36 / 40 10 5 5 5
San Angelo 51 60 27 54 36 / 30 10 5 5 5
Junction 52 64 30 55 34 / 60 20 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
638 PM CST Sat Jan 31 2015
.AVIATION...
/00Z TAFS/
CEILINGS REMAIN BELOW 1500 FT ACROSS MOST OF WEST CENTRAL TX, WITH
MANY FORECAST TERMINALS EXPERIENCING IFR (OR WORSE) CONDITIONS.
THE PRIMARY RAIN SHIELD HAS MOVED EAST OF THE FORECAST AREA.
HOWEVER, ISENTROPIC ASCENT WILL RAMP UP OVERNIGHT, RESULTING IN
LOWERING CEILINGS AND POTENTIAL LIGHT PRECIPITATION, MAINLY IN THE
FORM OF DRIZZLE. THIS WILL KNOCK CLOUD BASES DOWN TO GENERALLY
700 FT OR LOWER AND SHOULD CAUSE PREVAILING VISIBILITIES TO DROP
TO 5 MILES OR LESS. SOME LOCATIONS MAY EXPERIENCE MORE SIGNIFICANT
REDUCTIONS IN VISIBILITY. EXPECT POOR FLIGHT CONDITIONS OVERNIGHT
BUT WINDS WILL VEER TO THE SOUTHWEST OVERNIGHT AHEAD OF A COLD
FRONT. THIS FRONT WILL MOVE THROUGH THE BIG COUNTRY MID/LATE
MORNING, BRINGING DRIER AIR INTO THE AREA AND ERODING THE LOW
CLOUDS FROM NORTH TO SOUTH THROUGHOUT THE DAY. GUSTY NORTH WINDS
WILL PREVAIL IN THE WAKE OF THIS FRONT.
JOHNSON
&&
.PREV DISCUSSION... /ISSUED 351 PM CST SAT JAN 31 2015/
SHORT TERM...
(TONIGHT AND SUNDAY )
LIGHT RAIN WAS MOVING NORTH OF I-20, AND EAST OF AN ABILENE...
BRADY...MASON LINE AT 3 PM. AN UPPER LOW WAS WEST OF EL PASO,
MOVING SLOWLY SOUTHEAST.
RAIN WAS PUSHING EAST AND ENDING OF WEST CENTRAL, FASTER THAN THE
MODELS INDICATED. INDEED AT THE CURRENT PACE, NEARLY ALL THE
PRESENT RAIN AT 3 PM WILL BE EAST OR NORTH OF WEST CENTRAL TEXAS
BY 6 PM. KEPT A CHANCE OF SHOWERS GOING OVERNIGHT, HOWEVER, WITH
THE EL PASO LOW SENDING WEAK DISTURBANCES EASTWARD. ADDITIONAL
RAINFALL AMOUNTS WILL BE LIGHT...RANGING FROM A TRACE TO A FEW
HUNDREDTHS INCH. THE NAM AND EC MODELS BRING ISOLATED TO SCATTERED
LIGHT SHOWERS OVER WEST CENTRAL TEXAS TONIGHT. THE GFS MODEL`S
CONVECTIVE ALGORITHM IS DRY. THE SHORT RANGE HRRR MODEL BRINGS IN
SCATTERED SHOWERS, MAINLY OVER CROCKETT COUNTY, THE CONCHO VALLEY
AND AREAS SOUTHWARD. TIMING WAS BETWEEN 9 PM AND 4 AM. THIS MAY
ACTUALLY BE THE BEST MODEL AS IT SEEMS TO LATCHED ON AN AREA OF
LIFT IN THE WATER VAPOR LOOP SOUTH OF EL PASO.
A COLD FRONT WILL MOVE THROUGH WEST CENTRAL TEXAS SUNDAY BRINGING
GUSTY NORTH WINDS BY NOON. THIS CLEAR LOW LEVEL MOISTURE AND
CLOUDS. SUNSHINE IN THE AFTERNOON SHOULD ALLOW AFTERNOON HIGHS TO
BE A 2-4 DEGREES WARMER THAN TODAY`S, DESPITE COLD AIR ADVECTION.
LONG TERM...
(SUNDAY NIGHT THROUGH NEXT SATURDAY)
WARMER WEATHER WILL MAKE A RETURN TO WEST CENTRAL TEXAS FOR THE
FIRST HALF OF THE WEEK. AN AREA OF HIGH PRESSURE CENTERED OVER THE
REGION ON MONDAY, WILL SLIDE OFF TO OUR EAST BY MID-WEEK. A
THERMAL RIDGE AT 850 MB WILL EXPAND EAST OVER THE AREA, ALLOWING
HIGH TEMPERATURES TO CLIMB FROM THE MID 50S ON MONDAY, TO THE MID
60S BY WEDNESDAY. A WEAK COLD FRONT APPROACHING THE AREA FROM THE
NORTH WEDNESDAY NIGHT, WILL WASH OUT NEAR INTERSTATE 10 DURING THE
DAY THURSDAY, BRINGING COOLER/DRIER AIR TO THE REGION. HOWEVER,
THIS WILL BE SHORT-LIVED, AS A LEE TROUGH DEVELOPS TO OUR WEST ON
FRIDAY. WITH A RETURN FLOW DEVELOPING, WARMER TEMPERATURES AND
INCREASING MOISTURE ARE EXPECTED.
PRECIPITATION CHANCES MAY ALSO INCREASE FOR THE SOUTHERN HALF OF
THE FORECAST AREA. AN UPPER-LEVEL DISTURBANCE CURRENTLY LOCATED
OVER BAJA CALIFORNIA, IS EXPECTED TO PASS BY TO OUR SOUTHEAST
TUESDAY NIGHT/WEDNESDAY MORNING. THIS SYSTEM MAY BRING A CHANCE OF
RAIN TO THE REGION, MAINLY SOUTH OF A LINE FROM SAN ANGELO TO
BROWNWOOD. THIS AFTERNOON`S NUMERICAL MODELS HAVE ONCE AGAIN
SHIFTED THE TRACK OF THE DISTURBANCE FARTHER SOUTH AND EAST,
REDUCING FORECAST CONFIDENCE. HOWEVER, THE MODELS HAVE BEEN FLIP-
FLOPPING ON THE TRACK FOR THE LAST FEW MODEL RUNS, AND CONSIDERING
THE SYSTEM IS STILL LARGELY IN A DATA-VOID REGION, THIS WILL
LIKELY CONTINUE THROUGH THE NEXT 48 HOURS. BY THEN, THE SYSTEM
WILL ENTER AN IMPROVING OBSERVATIONAL/UPPER-AIR NETWORK, WHICH MAY
RESULT IN IMPROVED MODEL CONTINUITY. GIVEN THE CONCERNS MENTIONED
ABOVE, ONLY MINIMAL CHANGES WERE MADE TO THE RAINFALL FORECAST FOR
THE MIDDLE OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 49 51 24 51 36 / 40 10 5 5 5
SAN ANGELO 51 60 27 54 36 / 30 10 5 5 5
JUNCTION 52 64 30 55 34 / 60 20 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
25
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
454 PM CST FRI JAN 30 2015
.DISCUSSION...HAVE ISSUED A SMALL CRAFT ADVISORY FOR PORTIONS OF
THE MIDDLE TEXAS COASTAL WATERS FOR THE REMAINDER OF THIS
AFTERNOON AND INTO PART OF THE EVENING. LATEST RAP AND NAM
GUIDANCE INDICATES WIND SPEEDS SHOULD REMAIN STRONG ENOUGH INTO
THE EARLY EVENING HOURS TO JUSTIFY A SCA. ALSO LOWERED MIN TEMPS
FOR PORTIONS OF THE COASTAL COUNTIES AND BARRIER ISLANDS AS
CURRENT TEMPS ARE ALREADY AT OR BELOW PREVIOUSLY FORECAST MINS.
NO OTHER CHANGES OF SIGNIFICANCE MADE AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 314 PM CST FRI JAN 30 2015/
SHORT TERM (TONIGHT THROUGH SATURDAY NIGHT)...MOISTURE CONTINUES
TO INCREASE ACROSS ALL OF SOUTH TEXAS ON AN EAST TO SOUTHEAST WIND
JUST ABOVE THE SURFACE. PWATS NOW BETWEEN 1.1 AND 1.2 INCHES OVER
THE REGION. MOST OF THIS MOISTURE IS STILL CONFINED TO THE LOWEST
LAYERS AND WILL TAKE SOME TIME FOR THE VERY DRY AIR ALOFT TO
MOISTEN. THIS IS THE REASON CLOUDS HAVE BEEN LESS THAN ANTICIPATED
TODAY...JUST ACROSS THE BORDER IN MEXICO OVERCAST SKIES ARE NOTED
ON VIS SATELLITE...BUT AS THEY HAVE TRIED TO PUSH EASTWARD...MUCH
OF THE CLOUD COVER HAS DISSIPATED. STILL EXPECT CLOUDS TO DEVELOP
LATE THIS EVENING AND THEN CONTINUE THROUGH THE NIGHT AND
TOMORROW. SOME MODELS DO INDICATE CLEARING FOR EASTERN COUNTIES
TOMORROW MORNING...BUT LEANING MORE TOWARD THE CLOUDY SOLUTIONS.
RAIN WILL ALSO BE SLOW TO PUSH EASTWARD...HAVE SLOWED POP
INCREASES A BIT TONIGHT AND DURING THE DAY ON SATURDAY...WITH RAIN
MAINLY IN WESTERN COUNTIES IN THE MORNING...GRADUALLY SHIFTING
EASTWARD BY MID/LATE AFTERNOON. BEST DYNAMICS WITH THIS
APPROACHING SYSTEM WILL BE SATURDAY NIGHT WHEN UPPER LEVEL
SHORTWAVE PASSES...AND NOSE OF UPPER JET INCHES IN. THIS PERIOD IS
WHERE HIGHEST POPS WILL BE NOTED...AS WELL AS A SLIGHT CHANCE FOR
THUNDERSTORMS.
EXPECT MAINLY MILD TEMPERATURES THROUGH THE SHORT TERM PERIOD WITH
CLOUD COVER KEEPING MIN TEMPS INTO THE 50S BOTH TONIGHT AND TOMORROW
NIGHT. THINK HIGHS TOMORROW WILL BE SIMILAR TO TODAY...IN THE UPPER
60S TO AROUND 70.
LONG TERM (SUNDAY THROUGH FRIDAY)...CONCUR WITH THE GFS/ECMWF THAT
AN UPPER SYSTEM WL MOVE ACRS THE PLAINS AT THE BEGINNING OF THE
PERIOD AND CONTRIBUTE TO A COLD FRONT ACRS THE CWA/MSA SUNDAY/SUNDAY
NIGHT. EXPECT THE COMBINATION OF THE FRONT...ABOVE NORMAL PWAT
VALUES (GFS DETERMINISTIC)...AND UPPER JET DYNAMICS (GFS
DETERMINISTIC) TO GENERATE AT LEAST SCT CONVECTION OVER THE REGION
SUNDAY. SCA CONDITIONS ARE EXPECTED OVER THE MSA SUNDAY NIGHT/MONDAY
AFTER FROPA. ANTICIPATE THAT PCPN WL CONTINUE AFTER FROPA THROUGH
EARLY MONDAY OWING TO UPPER JET DYNAMICS. THE GFS/ECMWF PROG ANOTHER
UPPER SYSTEM MOVG ACRS THE NRN MEXICO AND PROVIDE SYNOPTIC SCALE
LIFT MONDAY NGT/TUESDAY. TIMING DIFFERENCES BETWEEN THE SOLNS
SUGGEST PCPN WL END TUESDAY NIGHT OR WEDNESDAY. WL COMPROMISE WITH
PCPN REMAINING OVER THE EXTREME ERN CWA/MSA WEDNESDAY. FURTHER...AS
THE UPPER SYSTEM APPROACHES...BOTH THE GFS AND ECMWF DETERMINISTIC
PROG A TROUGH OF LOW PRESSURE TO DEVELOP OVER THE SWRN GULF MONDAY
NIGHT/TUESDAY AND MAINTAIN AT LEAST A MODERATE NORTHEAST FLOW DRG
THAT TIME. NO PCPN EXPECTED THURSDAY/FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 56 68 59 72 47 / 10 30 40 40 30
VICTORIA 49 66 57 68 42 / 10 40 50 50 20
LAREDO 58 71 58 73 48 / 30 40 50 30 30
ALICE 56 70 58 73 47 / 10 40 50 40 30
ROCKPORT 56 64 60 64 47 / 10 30 40 40 30
COTULLA 52 68 56 70 44 / 30 60 40 30 20
KINGSVILLE 57 70 59 74 48 / 10 30 40 40 30
NAVY CORPUS 56 65 60 65 49 / 10 30 40 40 30
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 PM CST THIS EVENING FOR
THE FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT
ARANSAS OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS
FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA
SHIP CHANNEL FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 PM CST THIS EVENING FOR
THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO
PORT ARANSAS.
&&
$$
UPDATE...HART/79
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1228 AM EST FRI JAN 30 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE RAPIDLY EAST ACROSS THE OHIO VALLEY
TONIGHT AND INTO NEW ENGLAND BY FRIDAY MORNING. A SURFACE COLD
FRONT WILL TRAIL SOUTH FROM THE LOW...AND WILL SWEEP SOUTHEAST
ACROSS THE OHIO VALLEY TONIGHT...THEN THROUGH THE MID ATLANTIC
REGION FRIDAY MORNING. HIGH PRESSURE WILL THEN BUILD ACROSS THE
REGION FOR FRIDAY NIGHT AND SATURDAY...FOLLOWED BY AN AREA OF LOW
PRESSURE WHICH WILL MOVE FROM TEXAS SUNDAY...TO THE MID ATLANTIC
COAST BY MONDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1124 PM EST THURSDAY...
MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES AND DEW POINT
TEMPERATURES FOR TONIGHT. SFC TEMPERATURES WERE RUNNING A LITTLE
WARMER IN A FEW LOCATIONS...BUT WILL DROP BEHIND THE COLD FRONT.
THE COLD FRONT HAS REACH THE MOUNTAINS TONIGHT AND WILL MOVE EAST
ACROSS THE REGION FRIDAY MORNING. KFCX 88D SHOWING LIGHT RETURNS
ALONG THE WESTERN SLOPES. BOTH THE NAM AND HRRR SUPPORT CURRENT
FORECAST WITH UPSLOPE SNOW SHOWERS AND SNOW FLURRIES LATER
TONIGHT. INITIALLY EXPECTED SOME RAIN SHOWERS BEFORE TRANSITION
OVER TO SNOW TONIGHT. WINTER WEATHER ADVISORIES CONTINUES FOR
WESTERN GREENBRIER INTO FRIDAY. WIND ADVISORIES REMAIN ALONG AND
WEST OF THE BLUE RIDGE INTO FRIDAY NIGHT.
AS OF 715 PM EST THURSDAY...
CURRENT FORECAST IS ON TRACK WITH ALL OF THE ACTION YET TO COME A
LITTLE BIT LATER THIS EVENING. APPROACHING COLD FRONT IS CURRENTLY
ENTERING WEST VIRGINIA AND EASTERN KENTUCKY WHERE WINDS HAVE COME
AROUND TO NW AND RADAR SHOWS SOME LIGHT RETURNS BEHIND THE FRONT.
TEMPS WILL BE FALLING BEHIND THE FRONT AND EXPECT WE WILL FALL
ABOUT 10F BELOW CURRENT VALUES FOR LOWS OF LOWER 30S EAST OF THE
RIDGE WITH LOW/MID 20S WEST.
THE FRONT SHOULD REACH THE WESTERN SLOPES OF THE APPALACHIANS
AROUND 9PM AND START TO KICK OFF UPSLOPE SNOW SHOWERS. CURRENT
SNOW ACCUMULATION FORECAST LOOKS GOOD BASED ON MESO MODELS WITH 2
TO 4 INCH ADVISORY CRITERIA SNOW FOR WESTERN GREENBRIER INTO
FRIDAY MORNING AND LIGHTER AMOUNTS FURTHER SOUTH ALONG THE WESTERN
SLOPES. THE NC MOUNTAINS ARE LOOKING GOOD FOR AROUND 2 INCHES.
WINDS ARE CURRENTLY QUITE TAME BUT THAT WILL CHANGE BEHIND THE
FRONT. WINDS WILL BECOME NW AND REALLY START TO BLOW AFTER
MIDNIGHT WHEN THE WIND ADVISORIES START TO GO INTO EFFECT. GUSTS
OF 50 MPH TO 55 MPH CAN BE EXPECTED FOR THE NC MOUNTAINS INTO THE
GRAYSON HIGHLANDS...AND 40 MPH TO 50 MPH GUSTS WILL SPREAD NORTH
INTO THE BLUE RIDGE OVERNIGHT. THE WINDY CONDITIONS WILL CONTINUE
THROUGH FRIDAY BEFORE GRADUALLY SUBSIDING TOMORROW NIGHT.
PREVIOUS AFD...
NORTHWEST WINDS WILL BEGIN TO INCREASE AND THE UPSLOPE RAIN/SNOW
MACHINE WILL INITIATE OVER SOUTHEAST WEST VIRGINIA...SOUTH INTO
THE NORTHERN MOUNTAINS OF NORTH CAROLINA. OUR LATEST SNOWFALL
TOTALS DO NOT DIFFER GREATLY FROM OUR PRIOR FORECAST. ADVISORY
LEVEL SNOWS STILL LOOK PROMISING ACROSS WESTERN GREENBRIER COUNTY
IN THE TWO TO FOUR RANGE. HAVE INCREASED WESTERN PARTS OF
GRAYSON...ASHE...AND WATAUGA COUNTIES INTO THE ONE TO TWO INCH
RANGE. LOW TEMPERATURES TONIGHT WILL RANGE FROM THE LOW TO MID 20S
ACROSS THE MOUNTAINS WITH READINGS AROUND 30 TO THE LOWER 30S
ACROSS THE PIEDMONT.
WIND GUSTS ARE EXPECTED TO REACH ADVISORY LEVEL TONIGHT...FIRST
ACROSS THE NORTHERN MOUNTAINS NORTH CAROLINA AND THE GRAYSON
HIGHLANDS A LITTLE AFTER MIDNIGHT. AS THE NIGHT
PROGRESSES...ADVISORY LEVEL GUSTS WILL SPREAD NORTH ACROSS THE
HIGHER RIDGES OF SOUTHWEST VIRGINIA...AND THE WESTERN PORTIONS OF
WESTERN GREENBRIER COUNTY. THE HIGHER TERRAIN OF
GRAYSON...ASHE...AND WATAUGA MAY BE APPROACH GUSTS WITH SPEEDS AT
HIGH WIND WARNING CRITERIA FRIDAY MORNING. THE GUSTS WILL WEAKEN
JUST SLIGHTLY DURING FRIDAY AFTERNOON...PRIOR TO AN EXPECTED BRIEF
INCREASE FRIDAY EVENING. SNOW WILL GRADUALLY COME TO AN END DURING
THE DAY...BUT LINGER THE LONGEST ACROSS SOUTHEAST WEST VIRGINIA.
HIGH TEMPERATURES WILL RANGE FROM THE MID 20 TO LOWER 30S ACROSS
THE MOUNTAINS...WITH MANY OF THESE READINGS OCCURRING EARLY IN THE
DAY WITH FALLING TEMPERATURES THEREAFTER. THE PIEDMONT WILL
EXPERIENCE HIGHS IN THE UPPER 30S TO LOWER 40S.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
AS OF 240 PM EST THURSDAY...
LOW PRESSURE OFF THE NEW ENGLAND COAST AND HIGH PRESSURE SLIDING
ACROSS THE OHIO VALLEY WILL KEEP A PRESSURE GRADIENT AND WINDY/GUSTY
CONDITIONS ACROSS THE REGION INTO MONDAY EVENING. THROUGH THE NIGHT
HIGH PRESSURE EDGES INTO THE AREA WITH SOME LOCATIONS BEING ABLE TO
DECOUPLE WHILE BREEZY/GUSTY CONDITIONS REMAIN ACROSS THE MOUNTAINS.
MORNING LOWS WITHOUT THE WIND WILL RANGE FROM 5F TO 15F ACROSS THE
MOUNTAINS TO AROUND 20F EAST OF THE BLUE RIDGE. IF MIXING CONTINUES
INTO SATURDAY MORNING...WIND CHILLS NEAR ZERO ACROSS THE HIGHER
ELEVATIONS TO AROUND 10F ABOVE IN THE LOWER ELEVATIONS. IN THE
EAST...UPPER TEEN WIND CHILLS LIKELY. HIGH PRESSURE BUILDS OVER THE
REGION SATURDAY...THEN SLIDES TO THE SOUTHEAST SATURDAY NIGHT.
MOSTLY SUNNY SKIES SATURDAY WITH TEMPERATURES WARMING INTO THE UPPER
30S WEST TO MID 40S EAST. THE NEXT PRECIPITATION MAKER WILL PUSH
CLOUDS OVER THE AREA SATURDAY NIGHT WITH LOWS DROPPING JUST BELOW
FREEZING.
COMPLICATED WEATHER PATTERN WILL BRING PRECIPITATION INTO THE AREA
SUNDAY. AN UPPER LEVEL LOW OVER THE SOUTHWEST UNITED STATES WILL
THROW ENERGY AND MOISTURE INTO THE PLAINS. AN UPPER LEVEL NORTHERN
STREAM TROUGH WILL SWING OUT OF THE ROCKIES SATURDAY NIGHT. A SERIES
OF SHORT WAVES WILL TRACK ACROSS THE MID WEST AND EVENTUALLY SPIN UP
A SURFACE WAVE OVER THE TENNESSEE VALLEY. ALL THIS ENERGY/MOISTURE
WILL TRACK IN ZONAL FLOW AND INTO THE DEPARTING SURFACE RIDGE. THE
FIRST SIGNS OF MEASURABLE PRECIPITATION MAY HOLD OFF UNTIL THE
AFTERNOON. THE SURFACE LOW AND UPPER LEVEL DYNAMICS COMES ACROSS THE
AREA SUNDAY NIGHT AND HAVE RAISED POPS INTO THE HIGH LIKELY CATEGORY.
THE TOUGH QUESTION NOW DEALS WITH P-TYPE. TEMPERATURES AND
THICKNESSES START COLD ACROSS THE MOUNTAINS FOR PRECIPITATION TO
FALL AS SNOW. IF DRY AIR IS LEFT-OVER FROM DEPARTING
HIGH...PRECIPITATION FALLING COULD SEND WET BULB TEMPERATURES DOWN
BELOW FREEZING (NAM)...KEEPING MOUNTAIN PRECIPITATION AS SNOW AND A
COLD RAIN IN THE EAST. IF THE SURFACE LOW BECOMES STRONGER...MORE
WARM AIR WILL SURGE INTO THE AREA (GFS) CHANGING SNOW OVER TO RAIN
THROUGH THE DAY SUNDAY...THEN COLD AIR ENTERS LATE SUNDAY NIGHT TO
CHANGE RAIN BACK TO SNOW. BEING RIGHT IN THE TRACK OF THE LOW AND
LIMITED DENDRITE GROWTH NOT SUPPORTING STAYING ALL SNOW...WE WILL
LEAN TO A MOSTLY RAIN EVENT SUNDAY...CHANGING OVER TO SNOW WHEN THE
COLD FRONT PASSES SUNDAY NIGHT. ALSO...WE ARE NOT LOOKING AT A WEDGE
LINGERING IN THE REGION...THEREFORE HIGHLY CONFIDENT PRECIPITATION
WILL BE RAIN OR SNOW...NOT A MIXTURE OR CHANGE OVER TO FREEZING
RAIN/SLEET.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 330 PM EST THURSDAY...
TEMPERATURES BELOW NORMAL THROUGH THE EXTENDED...TRENDING TO MUCH
BELOW NORMAL TOWARD THE END OF NEXT WEEK.
MODELS KEEP THINGS PROGRESSIVE AND ARE CONSISTENT IN PHASING THE
UPPER LEVEL SPLIT FLOW PATTERN INTO A LONG WAVE WESTERN
TROF/EASTERN RIDGE PATTERN. THIS WILL OPEN THE DOOR FOR A SHOT OF
ARCTIC AIR AS WE GET TOWARD THE END OF THE PERIOD.
WE START THE PERIOD WITH A COASTAL LOW OFF THE MIDDLE ATLANTIC
COAST PULLING AWAY FROM THE REGION...LEAVING US WITH COLDER AIR
MOVING IN AND RESIDUAL NORTHWEST UPSLOPE FLOW SNOW SHOWERS WEST OF
THE BLUE RIDGE. THE SNOW SHOWERS COME TO AN END MONDAY NIGHT AS
HIGH PRESSURE BUILDS IN FROM THE OHIO VALLEY AND BRINGS US QUIET
AND COLD WEATHER FOR TUESDAY AND TUESDAY NIGHT.
THE NEXT CHANCE FOR PRECIPITATION COMES ON WEDNESDAY AS DEEPENING
LOW PRESSURE SYSTEM IS DRIVEN BY A VIGOROUS SHOT WAVE THROUGH THE
GREAT LAKES REGION AND INTO CANADA. THIS WILL SWING A COLD FRONT
THROUGH THE REGION...OPENS THE DOOR TO ARCTIC HIGH PRESSURE
BUILDING IN FROM THE MIDWEST. MODEL RUN TO RUN VARIABILITY IN THE
EXTENDED HAS BEEN QUITE HIGH RECENTLY AND WHILE EVOLUTION OF THE
OVERALL SYNOPTIC PATTERN SEEMS SOLID...DO NOT HAVE A LOT OF
CONFIDENCE IN SPECIFICS FROM ANY OF THE INDIVIDUAL SOLUTIONS. THE
EURO IS QUITE AGGRESSIVE IN DIGGING THE EASTERN TROF AND DEVELOPS
A COASTAL LOW MOVING OUT OF THE GULF WITH A CHANCE OF WINTRY
PRECIPITATION FOR OUR NORTH AND WEST AREAS...WHILE THE GFS/NAEFS
IS LESS AMPLIFIED AND DOES NOT ADVERTISE A COASTAL LOW AND KEEPS
US MOSTLY DRY. WILL HAVE TO WAIT AND SEE HOW THIS ALL PLAYS OUT IN
LATER MODEL RUNS BUT FOR NOW WILL SHADE THE FORECAST TOWARD THE
DRIER GFS/NAEFS.
&&
.AVIATION /05Z FRIDAY THROUGH TUESDAY/...
AS OF 1215 AM EST FRIDAY...
THE STRONG ADVERTISED ALBERTA CLIPPER COLD FRONT MOVING RAPIDLY
THROUGH THE WESTERN PART OF THE CWA AT THIS HOUR...NEAR BCB AND
ALREADY THROUGH LWB/BLF. VERY QUICKLY CIGS DROP INTO THE MVFR/IFR
RANGE BEHIND THE FRONT WITH MIXED PCPN...WHICH SHOULD RAPIDLY
CHANGE TO SNOW WITH STRONG LOW-LEVEL COLD ADVECTION. ALONG AND
EAST OF THE BLUE RIDGE...WINDS LIGHT AND VARIABLE WITH MOSTLY LOW
END VFR CIGS AT THIS HOUR. MODELS NOW DEPICTING A WAVE THAT WILL
RIDE ALONG THE FRONT...WHICH COULD SLIGHTLY DELAY ITS PROGRESS
INTO THE PIEDMONT AND FURTHERMORE BRING A WAVE OF -SHRA TO BCB/ROA
BEFORE THE COLD FRONT ARRIVES OR SHORTLY THEREAFTER. HAVE THUS INTRODUCED
THESE CHANGES TO THE TAFS...SLIGHTLY DELAYING THE ARRIVAL OF THE
FRONT INTO ROA/LYH/DAN AND ALSO INTRODUCING -SHRA TO BCB/ROA THAT
WERE NOT IN THE 00Z TAFS. UPSLOPE -SHSN SHOULD CONTINUE TO BE
ENHANCED WEST OF THE BLUE RIDGE OVERNIGHT INTO EARLY FRI...WITH
OCCASIONAL MVFR TO BRIEFLY IFR VSBYS AND IFR-LIFR CIGS. CONDITIONS
SHOULD BEGIN TO IMPROVE AFT 14Z WITH JUST FLURRIES OR OCCASIONAL
-SHSN THROUGH THE EARLY AFTERNOON WEST OF THE BLUE RIDGE. EXPECT
MVFR CIGS TO HOLD MUCH OF THE DAY WEST OF THE BLUE RIDGE...BUT
CLOUDS SHOULD SCATTER OUT TO THE EAST. EXPECT VFR CIGS AROUND 22Z
BLF/LWB/BCB...BECOMING MOSTLY SKC OR JUST SCT ALL SITES AFT 22Z.
MAIN CONCERN THROUGH THE TAF VALID PERIOD WILL BE STRONG...GUSTY
NORTHWEST WINDS. WITH A 50KT NORTHWESTERLY LLJ OVER THE REGION
LATE TONIGHT/EARLY FRI AS A TIGHT PRESSURE GRADIENT DEVELOPS
BETWEEN THE ADVANCING CANADIAN HIGH AND THE DEPARTING SFC LOW
NORTHEAST U.S...30-40KT WIND GUSTS WILL BE POSSIBLE LATE TONIGHT
AND THROUGH EARLY AFTERNOON FRI. SUSTAINED WINDS SHOULD BE MAINLY
IN THE 15-25KT RANGE. WINDS REMAIN GUSTY EVEN INTO FRI
EVENING...BUT SHOULD DROP BELOW 25KTS FAIRLY QUICKLY AFT 02Z.
WINDS OVERALL WILL AVERAGE 10KTS LESS ACROSS THE PIEDMONT.
MEDIUM CONFIDENCE IN CIGS AND VSBYS THROUGH 14Z...THEN MEDIUM TO
HIGH CONFIDENCE.
MEDIUM TO HIGH CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID
PERIOD.
EXTENDED DISCUSSION...
WINDS WILL DIMINISH FRIDAY NIGHT AS HIGH PRESSURE MOVES INTO THE
REGION FROM THE WEST. ANY REMAINING LOW CLOUDS LINGERING ACROSS
EASTERN WV SHOULD DISSIPATE...WITH VFR CIGS EXPECTED FRI NIGHT AND
SAT. THE NEXT LOW PRESSURE SYSTEM HEADING OUT OF THE SW STATES
WILL BRING A RETURN OF CLOUDS AND PRECIPITATION ON SUNDAY WITH
WIDESPREAD MVFR TO IFR CIGS/VSBYS LIKELY WITHIN THIS TIME FRAME.
THE NORTHERN SECTIONS OF THE CWA WILL LIKELY SEE MOSTLY WINTER
PRECIPITATION WITH THIS EVENT...WHILE THE SOUTHERN AREAS SHOULD
SEE MOSTLY RAIN. IN BETWEEN...LOCATIONS SUCH AS
BCB/ROA/LYH...COULD SEE A MIX OF RAIN AND SNOW. MOUNTAIN SNOW
SHOWERS WITH MVFR CIGS/VSBYS WILL CONTINUE INTO MON...WITH STRONG
AND GUSTY WINDS ALL AREAS BY MONDAY AFTERNOON. IMPROVING
CONDITIONS ARE EXPECTED BY TUESDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WIND ADVISORY UNTIL 9 PM EST THIS EVENING FOR VAZ009>014-
016>020-022>024-032>035.
WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VAZ015.
NC...WIND ADVISORY UNTIL 9 PM EST THIS EVENING FOR NCZ002.
WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NCZ001-018.
WV...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR WVZ508.
&&
$$
SYNOPSIS...DS
NEAR TERM...DS/KK/MBS
SHORT TERM...RCS
LONG TERM...MBS
AVIATION...DS/RAB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1124 PM EST THU JAN 29 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE RAPIDLY EAST ACROSS THE OHIO VALLEY
TONIGHT AND INTO NEW ENGLAND BY FRIDAY MORNING. A SURFACE COLD
FRONT WILL TRAIL SOUTH FROM THE LOW...AND WILL SWEEP SOUTHEAST
ACROSS THE OHIO VALLEY TONIGHT...THEN THROUGH THE MID ATLANTIC
REGION FRIDAY MORNING. HIGH PRESSURE WILL THEN BUILD ACROSS THE
REGION FOR FRIDAY NIGHT AND SATURDAY...FOLLOWED BY AN AREA OF LOW
PRESSURE WHICH WILL MOVE FROM TEXAS SUNDAY...TO THE MID ATLANTIC
COAST BY MONDAY.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 1124 PM EST THURSDAY...
MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES AND DEW POINT
TEMPERATURES FOR TONIGHT. SFC TEMPERATURES WERE RUNNING A LITTLE
WARMER IN A FEW LOCATIONS...BUT WILL DROP BEHIND THE COLD FRONT.
THE COLD FRONT HAS REACH THE MOUNTAINS TONIGHT AND WILL MOVE EAST
ACROSS THE REGION FRIDAY MORNING. KFCX 88D SHOWING LIGHT RETURNS
ALONG THE WESTERN SLOPES. BOTH THE NAM AND HRRR SUPPORT CURRENT
FORECAST WITH UPSLOPE SNOW SHOWERS AND SNOW FLURRIES LATER
TONIGHT. INITIALLY EXPECTED SOME RAIN SHOWERS BEFORE TRANSITION
OVER TO SNOW TONIGHT. WINTER WEATHER ADVISORIES CONTINUES FOR
WESTERN GREENBRIER INTO FRIDAY. WIND ADVISORIES REMAIN ALONG AND
WEST OF THE BLUE RIDGE INTO FRIDAY NIGHT.
AS OF 715 PM EST THURSDAY...
CURRENT FORECAST IS ON TRACK WITH ALL OF THE ACTION YET TO COME A
LITTLE BIT LATER THIS EVENING. APPROACHING COLD FRONT IS CURRENTLY
ENTERING WEST VIRGINIA AND EASTERN KENTUCKY WHERE WINDS HAVE COME
AROUND TO NW AND RADAR SHOWS SOME LIGHT RETURNS BEHIND THE FRONT.
TEMPS WILL BE FALLING BEHIND THE FRONT AND EXPECT WE WILL FALL
ABOUT 10F BELOW CURRENT VALUES FOR LOWS OF LOWER 30S EAST OF THE
RIDGE WITH LOW/MID 20S WEST.
THE FRONT SHOULD REACH THE WESTERN SLOPES OF THE APPALACHIANS
AROUND 9PM AND START TO KICK OFF UPSLOPE SNOW SHOWERS. CURRENT
SNOW ACCUMULATION FORECAST LOOKS GOOD BASED ON MESO MODELS WITH 2
TO 4 INCH ADVISORY CRITERIA SNOW FOR WESTERN GREENBRIER INTO
FRIDAY MORNING AND LIGHTER AMOUNTS FURTHER SOUTH ALONG THE WESTERN
SLOPES. THE NC MOUNTAINS ARE LOOKING GOOD FOR AROUND 2 INCHES.
WINDS ARE CURRENTLY QUITE TAME BUT THAT WILL CHANGE BEHIND THE
FRONT. WINDS WILL BECOME NW AND REALLY START TO BLOW AFTER
MIDNIGHT WHEN THE WIND ADVISORIES START TO GO INTO EFFECT. GUSTS
OF 50 MPH TO 55 MPH CAN BE EXPECTED FOR THE NC MOUNTAINS INTO THE
GRAYSON HIGHLANDS...AND 40 MPH TO 50 MPH GUSTS WILL SPREAD NORTH
INTO THE BLUE RIDGE OVERNIGHT. THE WINDY CONDITIONS WILL CONTINUE
THROUGH FRIDAY BEFORE GRADUALLY SUBSIDING TOMORROW NIGHT.
PREVIOUS AFD...
NORTHWEST WINDS WILL BEGIN TO INCREASE AND THE UPSLOPE RAIN/SNOW
MACHINE WILL INITIATE OVER SOUTHEAST WEST VIRGINIA...SOUTH INTO
THE NORTHERN MOUNTAINS OF NORTH CAROLINA. OUR LATEST SNOWFALL
TOTALS DO NOT DIFFER GREATLY FROM OUR PRIOR FORECAST. ADVISORY
LEVEL SNOWS STILL LOOK PROMISING ACROSS WESTERN GREENBRIER COUNTY
IN THE TWO TO FOUR RANGE. HAVE INCREASED WESTERN PARTS OF
GRAYSON...ASHE...AND WATAUGA COUNTIES INTO THE ONE TO TWO INCH
RANGE. LOW TEMPERATURES TONIGHT WILL RANGE FROM THE LOW TO MID 20S
ACROSS THE MOUNTAINS WITH READINGS AROUND 30 TO THE LOWER 30S
ACROSS THE PIEDMONT.
WIND GUSTS ARE EXPECTED TO REACH ADVISORY LEVEL TONIGHT...FIRST
ACROSS THE NORTHERN MOUNTAINS NORTH CAROLINA AND THE GRAYSON
HIGHLANDS A LITTLE AFTER MIDNIGHT. AS THE NIGHT
PROGRESSES...ADVISORY LEVEL GUSTS WILL SPREAD NORTH ACROSS THE
HIGHER RIDGES OF SOUTHWEST VIRGINIA...AND THE WESTERN PORTIONS OF
WESTERN GREENBRIER COUNTY. THE HIGHER TERRAIN OF
GRAYSON...ASHE...AND WATAUGA MAY BE APPROACH GUSTS WITH SPEEDS AT
HIGH WIND WARNING CRITERIA FRIDAY MORNING. THE GUSTS WILL WEAKEN
JUST SLIGHTLY DURING FRIDAY AFTERNOON...PRIOR TO AN EXPECTED BRIEF
INCREASE FRIDAY EVENING. SNOW WILL GRADUALLY COME TO AN END DURING
THE DAY...BUT LINGER THE LONGEST ACROSS SOUTHEAST WEST VIRGINIA.
HIGH TEMPERATURES WILL RANGE FROM THE MID 20 TO LOWER 30S ACROSS
THE MOUNTAINS...WITH MANY OF THESE READINGS OCCURRING EARLY IN THE
DAY WITH FALLING TEMPERATURES THEREAFTER. THE PIEDMONT WILL
EXPERIENCE HIGHS IN THE UPPER 30S TO LOWER 40S.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 240 PM EST THURSDAY...
LOW PRESSURE OFF THE NEW ENGLAND COAST AND HIGH PRESSURE SLIDING
ACROSS THE OHIO VALLEY WILL KEEP A PRESSURE GRADIENT AND WINDY/GUSTY
CONDITIONS ACROSS THE REGION INTO MONDAY EVENING. THROUGH THE NIGHT
HIGH PRESSURE EDGES INTO THE AREA WITH SOME LOCATIONS BEING ABLE TO
DECOUPLE WHILE BREEZY/GUSTY CONDITIONS REMAIN ACROSS THE MOUNTAINS.
MORNING LOWS WITHOUT THE WIND WILL RANGE FROM 5F TO 15F ACROSS THE
MOUNTAINS TO AROUND 20F EAST OF THE BLUE RIDGE. IF MIXING CONTINUES
INTO SATURDAY MORNING...WIND CHILLS NEAR ZERO ACROSS THE HIGHER
ELEVATIONS TO AROUND 10F ABOVE IN THE LOWER ELEVATIONS. IN THE
EAST...UPPER TEEN WIND CHILLS LIKELY. HIGH PRESSURE BUILDS OVER THE
REGION SATURDAY...THEN SLIDES TO THE SOUTHEAST SATURDAY NIGHT.
MOSTLY SUNNY SKIES SATURDAY WITH TEMPERATURES WARMING INTO THE UPPER
30S WEST TO MID 40S EAST. THE NEXT PRECIPITATION MAKER WILL PUSH
CLOUDS OVER THE AREA SATURDAY NIGHT WITH LOWS DROPPING JUST BELOW
FREEZING.
COMPLICATED WEATHER PATTERN WILL BRING PRECIPITATION INTO THE AREA
SUNDAY. AN UPPER LEVEL LOW OVER THE SOUTHWEST UNITED STATES WILL
THROW ENERGY AND MOISTURE INTO THE PLAINS. AN UPPER LEVEL NORTHERN
STREAM TROUGH WILL SWING OUT OF THE ROCKIES SATURDAY NIGHT. A SERIES
OF SHORT WAVES WILL TRACK ACROSS THE MID WEST AND EVENTUALLY SPIN UP
A SURFACE WAVE OVER THE TENNESSEE VALLEY. ALL THIS ENERGY/MOISTURE
WILL TRACK IN ZONAL FLOW AND INTO THE DEPARTING SURFACE RIDGE. THE
FIRST SIGNS OF MEASURABLE PRECIPITATION MAY HOLD OFF UNTIL THE
AFTERNOON. THE SURFACE LOW AND UPPER LEVEL DYNAMICS COMES ACROSS THE
AREA SUNDAY NIGHT AND HAVE RAISED POPS INTO THE HIGH LIKELY CATEGORY.
THE TOUGH QUESTION NOW DEALS WITH P-TYPE. TEMPERATURES AND
THICKNESSES START COLD ACROSS THE MOUNTAINS FOR PRECIPITATION TO
FALL AS SNOW. IF DRY AIR IS LEFT-OVER FROM DEPARTING
HIGH...PRECIPITATION FALLING COULD SEND WET BULB TEMPERATURES DOWN
BELOW FREEZING (NAM)...KEEPING MOUNTAIN PRECIPITATION AS SNOW AND A
COLD RAIN IN THE EAST. IF THE SURFACE LOW BECOMES STRONGER...MORE
WARM AIR WILL SURGE INTO THE AREA (GFS) CHANGING SNOW OVER TO RAIN
THROUGH THE DAY SUNDAY...THEN COLD AIR ENTERS LATE SUNDAY NIGHT TO
CHANGE RAIN BACK TO SNOW. BEING RIGHT IN THE TRACK OF THE LOW AND
LIMITED DENDRITE GROWTH NOT SUPPORTING STAYING ALL SNOW...WE WILL
LEAN TO A MOSTLY RAIN EVENT SUNDAY...CHANGING OVER TO SNOW WHEN THE
COLD FRONT PASSES SUNDAY NIGHT. ALSO...WE ARE NOT LOOKING AT A WEDGE
LINGERING IN THE REGION...THEREFORE HIGHLY CONFIDENT PRECIPITATION
WILL BE RAIN OR SNOW...NOT A MIXTURE OR CHANGE OVER TO FREEZING
RAIN/SLEET.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 330 PM EST THURSDAY...
TEMPERATURES BELOW NORMAL THROUGH THE EXTENDED...TRENDING TO MUCH
BELOW NORMAL TOWARD THE END OF NEXT WEEK.
MODELS KEEP THINGS PROGRESSIVE AND ARE CONSISTENT IN PHASING THE
UPPER LEVEL SPLIT FLOW PATTERN INTO A LONG WAVE WESTERN
TROF/EASTERN RIDGE PATTERN. THIS WILL OPEN THE DOOR FOR A SHOT OF
ARCTIC AIR AS WE GET TOWARD THE END OF THE PERIOD.
WE START THE PERIOD WITH A COASTAL LOW OFF THE MIDDLE ATLANTIC
COAST PULLING AWAY FROM THE REGION...LEAVING US WITH COLDER AIR
MOVING IN AND RESIDUAL NORTHWEST UPSLOPE FLOW SNOW SHOWERS WEST OF
THE BLUE RIDGE. THE SNOW SHOWERS COME TO AN END MONDAY NIGHT AS
HIGH PRESSURE BUILDS IN FROM THE OHIO VALLEY AND BRINGS US QUIET
AND COLD WEATHER FOR TUESDAY AND TUESDAY NIGHT.
THE NEXT CHANCE FOR PRECIPITATION COMES ON WEDNESDAY AS DEEPENING
LOW PRESSURE SYSTEM IS DRIVEN BY A VIGOROUS SHOT WAVE THROUGH THE
GREAT LAKES REGION AND INTO CANADA. THIS WILL SWING A COLD FRONT
THROUGH THE REGION...OPENS THE DOOR TO ARCTIC HIGH PRESSURE
BUILDING IN FROM THE MIDWEST. MODEL RUN TO RUN VARIABILITY IN THE
EXTENDED HAS BEEN QUITE HIGH RECENTLY AND WHILE EVOLUTION OF THE
OVERALL SYNOPTIC PATTERN SEEMS SOLID...DO NOT HAVE A LOT OF
CONFIDENCE IN SPECIFICS FROM ANY OF THE INDIVIDUAL SOLUTIONS. THE
EURO IS QUITE AGGRESSIVE IN DIGGING THE EASTERN TROF AND DEVELOPS
A COASTAL LOW MOVING OUT OF THE GULF WITH A CHANCE OF WINTRY
PRECIPITATION FOR OUR NORTH AND WEST AREAS...WHILE THE GFS/NAEFS
IS LESS AMPLIFIED AND DOES NOT ADVERTISE A COASTAL LOW AND KEEPS
US MOSTLY DRY. WILL HAVE TO WAIT AND SEE HOW THIS ALL PLAYS OUT IN
LATER MODEL RUNS BUT FOR NOW WILL SHADE THE FORECAST TOWARD THE
DRIER GFS/NAEFS.
&&
.AVIATION /04Z FRIDAY THROUGH TUESDAY/...
AS OF 650 PM EST THURSDAY...
THE CWA REMAINS IN ADVANCE OF A STRONG COLD FRONT ASSOCIATED WITH
AN ALBERTA CLIPPER. THE SLEET BAND HAS MOVED WELL EAST OF THE AREA
AND WILL NOT LONGER BE AN ISSUE. UNTIL THE FRONT
ARRIVES...GENERALLY 04Z BLF/LWB TO 08Z DAN...EXPECT MOSTLY BKN-OVC
LOW END MVFR CIGS IN THE 035-060 RANGE WEST TO EAST AND VFR VSBYS.
FOLLOWING FRONTAL PASSAGE...CIGS WEST OF THE BLUE RIDGE WILL
QUICKLY DROP INTO THE MVFR RANGE WITH -SHSN
DEVELOPING...ESPECIALLY WEST OF THE ALLEGHANY FRONT. BLF/LWB COULD
AT TIMES SEE IFR CIGS AND MVFR VSBYS IN THESE -SHSN ROUGHLY IN THE
08Z-14Z TIME FRAME...WITH FLURRIES CONTINUING THROUGH MUCH OF THE
REMAINDER OF THE TAF VALID PERIOD. FOR BCB...SOME -SHSN ARE
EXPECTED...BUT NOT EXPECTING VSBYS TO BE REDUCED THERE. EAST OF
THE BLUE RIDGE...SCT-BKN LOW END VFR CIGS MAY LINGER INTO THE
MORNING HOURS FOR ROA...BUT OTHERWISE...SKIES WILL BECOME SCT TO
SKC/VFR BY MIDDAY.
WINDS WILL BE THE MAIN CONCERN THROUGH THE TAF VALID PERIOD.
ALTHOUGH MODELS HAVE BACKED OFF SLIGHTLY FROM THE WINDS ADVERTISED
YESTERDAY...STILL EXPECT WNW WINDS SUSTAINED OF 15-20KTS WITH
GUSTS 30-35KTS TO DEVELOP ACROSS MUCH OF THE REGION WEST OF THE
BLUE RIDGE. FOR AREAS TO THE EAST...EXPECT WNW WINDS OF 10-15KTS
WITH GUSTS 20-25KTS. WINDS WILL INCREASE QUICKLY FOLLOWING THE
FRONTAL PASSAGE IN THE 04Z WEST TO 08Z EAST...BUT THE STRONGEST
WINDS WILL COME IN THE 14Z-20Z TIME FRAME. PRIOR TO THE FRONTAL
PASSAGE THIS EVENING...EXPECT MOSTLY SOUTH WINDS AT SPEEDS LESS
THAN 10KTS.
MEDIUM TO HIGH CONFIDENCE IN CIGS AND VSBYS THROUGH THE TAF VALID
PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID
PERIOD.
EXTENDED DISCUSSION...
WINDS WILL DIMINISH FRIDAY NIGHT AS HIGH PRESSURE MOVES INTO THE
REGION FROM THE WEST. ANY REMAINING LOW CLOUDS LINGERING ACROSS
EASTERN WV SHOULD DISSIPATE...WITH VFR CIGS EXPECTED FRI NIGHT AND
SAT. THE NEXT LOW PRESSURE SYSTEM HEADING OUT OF THE SW STATES
WILL BRING A RETURN OF CLOUDS AND PRECIPITATION ON SUNDAY WITH
WIDESPREAD MVFR TO IFR CIGS/VSBYS LIKELY WITHIN THIS TIME FRAME.
THE NORTHERN SECTIONS OF THE CWA WILL LIKELY SEE MOSTLY WINTER
PRECIPITATION WITH THIS EVENT...WHILE THE SOUTHERN AREAS SHOULD
SEE MOSTLY RAIN. IN BETWEEN...LOCATIONS SUCH AS
BCB/ROA/LYH...COULD SEE A MIX OF RAIN AND SNOW. MOUNTAIN SNOW
SHOWERS WITH MVFR CIGS/VSBYS WILL CONTINUE INTO MON...WITH STRONG
AND GUSTY WINDS ALL AREAS BY MONDAY AFTERNOON. IMPROVING
CONDITIONS ARE EXPECTED BY TUESDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WIND ADVISORY FROM 3 AM TO 9 PM EST FRIDAY FOR VAZ009>014-
016>020-022>024-032>035.
WIND ADVISORY UNTIL MIDNIGHT EST FRIDAY NIGHT FOR VAZ015.
NC...WIND ADVISORY FROM 3 AM TO 9 PM EST FRIDAY FOR NCZ002.
WIND ADVISORY UNTIL MIDNIGHT EST FRIDAY NIGHT FOR NCZ001-018.
WV...WINTER WEATHER ADVISORY UNTIL NOON EST FRIDAY FOR WVZ508.
&&
$$
SYNOPSIS...DS
NEAR TERM...DS/KK/MBS
SHORT TERM...RCS
LONG TERM...MBS
AVIATION...DS/RAB
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1029 PM MST SAT JAN 31 2015
.UPDATE...
ISSUED AT 809 PM MST SAT JAN 31 2015
UPDATED FORECAST TO ACCOUNT FOR RADAR TRENDS OVER EASTERN PLAINS
AN PRECIP DROPPING SOUTH TOWARDS THE PIKES PEAK REGION. ALSO
EXPIRING SNOW ADVISORIES FOR PARTS OF THE HIGH COUNTRY. /HODANISH
UPDATE ISSUED AT 447 PM MST SAT JAN 31 2015
FINE-TUNED FORECAST FOR LATEST RADAR TRENDS AND HRRR FCST. FIRST
BAND OF PRECIP WILL MOVE ACROSS THE REGION EARLY THIS EVENING
WITH ANOTHER BAND COMING ACROSS MAINLY THE PIKES PEAK REGION
TOWARDS MIDNIGHT. FIRST BAND ALREADY CLEARED C MTNS AND WILL
REMOVE SNOW ADVISORY FROM THIS REGION WITH THIS UPDATE.
UPDATE WILL BE ISSUED SHORTLY AFTER 5 PM. /HODANISH
/HODANISH
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 236 PM MST SAT JAN 31 2015
CURRENTLY...PRECIP EXPANDING ACROSS THE AREA AS LIFT INCREASES AHEAD
OF UPPER TROUGH DROPPING SOUTHWARD THROUGH THE NRN ROCKIES. SURFACE
COLD FRONT WAS ALONG THE PALMER DIVIDE AS OF 21Z...WITH PRECIP
EXPECTED TO EXPAND ALONG/BEHIND THE BOUNDARY INTO EARLY EVENING AS
IT DROPS SOUTH TOWARD THE NM BORDER. WARMER TEMPS HAVE HELD ON AHEAD
OF THE FRONT ALONG AND SOUTH OF THE ARKANSAS RIVER...AND EXPECT
PRECIP TO BEGIN AS RAIN BELOW ABOUT 6K FEET LATE THIS AFTERNOON.
FARTHER WEST..SNOW CONTINUES ACROSS THE HIGHER ELEVATIONS AND MOST
VALLEYS...THOUGH BACK EDGE OF STEADIER SNOW WAS ALREADY MOVING
TOWARD THE CENTRAL MOUNTAINS AS OF 21Z.
TONIGHT...LEFT CURRENT ROUND OF WINTER HIGHLIGHTS INTACT...THOUGH
WITH BACK EDGE OF SNOW DROPPING SOUTH OF I-70 ALREADY...CENTRAL
MOUNTAIN ADVISORY MAY NEED TO BE DROPPED EARLY WITH NEXT UPDATE.
ELSEWHERE...EXPECT A PERIOD OF SNOW OVER MOST MOUNTAINS AND HIGH
VALLEYS THROUGH THE EVENING...WITH FOCUS OF HEAVIER SNOW SHIFTING TO
THE EASTERN MOUNTAINS AS FLOW BECOMES WEAKLY UPSLOPE. HIGHER
PEAKS OF THE SANGRES/WETS/PIKES PEAK WILL SEE SOME MODEST (2-5 INCH)
ACCUMULATIONS THIS EVENING...WHILE VALLEYS SEE A QUICK INCH OR TWO.
PRECIP ON THE PLAINS BELOW ABOUT 6K FEET WILL START AS RAIN...WITH A
GRADUAL CHANGE OVER TO SNOW AFTER SUNSET AS COLDER AIR AT THE
SURFACE AND ALOFT SPREADS SOUTH. LATE CHANGEOVER AND WARM GROUND
WILL LIMIT ACCUMS ON THE PLAINS...THOUGH EL PASO COUNTY COULD SEE A
INCH OR TWO ONCE TEMPS DROP BELOW FREEZING AFTER SUNSET. PAST 04Z-
06Z...LIFT DECREASES OVER MOUNTAINS/WRN VALLEYS AS TROUGH DROPS
SOUTH...WITH SNOW FADING AWAY FAIRLY QUICKLY BY LATE EVENING.
EASTERN MOUNTAINS WILL LIKELY HOLD ON TO SNOW LONGER AS WEAK
UPSLOPE COMPONENT KEEPS AT LEAST SOME LIGHT SNOW GOING INTO SUN
MORNING. OVERNIGHT LOWS WILL DROP BELOW FREEZING MOST LOCATIONS AS
DRIER/COLDER AIR FILTERS SOUTH THROUGH THE NIGHT.
SUNDAY...STILL SOME LINGERING LIGHT SNOW ALONG/WEST OF I-25 IN THE
MORNING...GRADUALLY FADING TO FLURRIES IN THE AFTERNOON AS UPSLOPE
FADES AND UPPER JET SHIFTS INTO THE CENTRAL PLAINS. DESPITE SOME SUN
MANY AREAS BY AFTERNOON...CONTINUED COLD ADVECTION WILL KEEP TEMPS
FAIRLY COOL WITH MOST LOCATIONS IN THE 30S OR COLDER.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 236 PM MST SAT JAN 31 2015
MODELS CONTINUE TO HAVE DIFFERENCES IN THE MIDDLE OF THE EXTENDED
PERIOD WITH THE ECMWF HAVE BETTER ENSEMBLE SUPPORT THAN THE GFS
SOLUTION.
SUNDAY NIGHT THROUGH TUESDAY...THE UPPER PATTERN WILL FEATURE A
TROUGH MOVING OFF TO THE EAST WHILE AN UPPER RIDGE DEVELOPS ALONG
THE WEST COAST. THIS WILL PUT SOUTHERN COLORADO UNDER BROAD
NORTHWESTERLY FLOW ALOFT. SNOW WILL BE WINDING DOWN OVER THE
SOUTHERN SANGRE DE CRISTO MOUNTAINS SUNDAY EVENING WITH DRY
CONDITIONS EXPECTED ACROSS MOST OF THE REGION BY MONDAY MORNING.
THE EXCEPTION WILL BE THE CENTRAL MOUNTAINS. THE PERSISTENT
NORTHWESTERLY FLOW IS FAVORED OROGRAPHICALLY AND CONTINUOUS LIGHT
SNOW WILL PREVAIL OVER THE CENTRAL MOUNTAINS THROUGH TUESDAY
NIGHT. ACCUMULATIONS OF 3 TO 6 INCHES WITH LOCALLY HIGHER
AMOUNTS ARE POSSIBLE SUNDAY NIGHT THROUGH TUESDAY NIGHT. DRY
CONDITIONS WILL PREVAIL ACROSS THE EASTERN PLAINS. MIXING OF
NORTHWESTERLY FLOW WILL BRING WARMING TEMPERATURES TO THE LOWER
ELEVATIONS...WITH 50S FOR HIGHS ON MONDAY...AND 60S ON TUESDAY.
WEDNESDAY...MODELS CONTINUE TO STRUGGLE WITH THE NEXT WEATHER
SYSTEM EXPECTED TO REACH THE AREA ON WEDNESDAY. THE GFS IS THE
MOST AGGRESSIVE WITH THIS SHORTWAVE TROUGH...WHICH IS FORECAST TO
DROP SOUTH OUT OF THE NORTHERN ROCKIES. THE GFS DROPS A COLD
FRONT ACROSS EASTERN COLORADO AND DEVELOPS WIDESPREAD RAIN
CHANGING TO SNOW WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT BEFORE
CLEARING THE AREA BY THURSDAY MORNING. THE ECMWF...WHICH HAS
BETTER ENSEMBLE SUPPORT...IS MUCH DIFFERENT THAN THE GFS. IT TAKES
THE UPPER LEVEL SHORTWAVE TROUGH OUT OF MONTANA...AND BARELY CLIPS
NORTHEAST COLORADO AS IT TRACKS INTO THE CENTRAL PLAINS. IT ALSO
HAS A COLD FRONT BY WEDNESDAY EVENING OVER THE PLAINS...BUT DOES
NOT HAVE MUCH IN THE WAY OF PRECIPITATION ACROSS THE REGION. IT
HAS SNOW OVER THE CENTRAL MOUNTAINS...AND PERHAPS THE PALMER
DIVIDE WEDNESDAY NIGHT...BUT KEEPS THE EASTERN PLAINS DRY. FOR NOW
HAVE LOW POPS ACROSS THE PLAINS...BUT CONFIDENCE IS LOW AT THIS
TIME. TEMPERATURES ON WEDNESDAY WILL DEPEND ON FRONTAL TIMING WITH
40S TO LOWER 50S EXPECTED.
THURSDAY THROUGH SATURDAY...BROAD NORTHWESTERLY FLOW WILL
REDEVELOP ACROSS THE REGION AS HIGH PRESSURE OVER THE WEST MOVES
SLOWLY EASTWARD. LIGHT SNOW OVER THE CENTRAL MOUNTAINS IS FORECAST
TO DISSIPATE BY FRIDAY AS DRIER AIR ALOFT MOVES INTO THE AREA.
TEMPERATURES WILL ALSO REBOUND WITH 50S AND 60S BY FRIDAY AND
SATURDAY. MOZLEY
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1026 PM MST SAT JAN 31 2015
KCOS...COLD FRONT WILL MOVE THROUGH LATER TONIGHT. WE MAY SEE SOME
SNOW SHOWERS AND LOWER CIGS BETWEEN 07-11Z TONIGHT WITH SNOW AND
CLOUDS...OTHERWISE VFR EXPECTED THROUGH 02/06Z
KPUB...VFR NEXT 24H. MAY SEE SOME LIGHT BR THROUGH 08Z.
KALS...GUIDANCE SHOWS IT DRYING OUT TONIGHT BUT KALS CAN BE
PROBLEMATIC DUE TO THE VALLEY. FOR NOW WENT WITH TRENDS IN
GUIDANCE BUT DELAYED LOW CLOUDS GETTING OUT OF THE VALLEY UNTIL
LATER ON TONIGHT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT FOR COZ074-
075.
&&
$$
UPDATE...HODANISH
SHORT TERM...PETERSEN
LONG TERM...MOZLEY
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
347 AM CST SUN FEB 1 2015
.SHORT TERM...
347 AM CST
THROUGH MONDAY...
HAVE BEEN SWAMPED THIS MORNING AND AM RUNNING BEHIND...SO GOING TO
KEEP DISCUSSION BRIEF THIS MORNING AND JUST HIT THE IMPORTANT
CHANGES. THE BIGGEST CHANGES TO GOING FORECAST IS THE UPGRADE TO
A BLIZZARD WARNING FOR PORTIONS OF NE IL/CHICAGO METRO AND TO
LOWER SNOW AMOUNTS AND ADD MIXED PRECIP BACK INTO GRIDS FAR SE
CWA.
GUIDANCE HAS CONTINUED TO TREND NORTH AND STRONGER WITH THE TRACK OF
THIS SYSTEM AND COMPARING GUIDANCE WITH SFC OBS AND BEST SFC
PRESSURE FALLS IT WOULD SEEM TO SUPPORT THE FARTHER NORTH TRACK THAT
THE RAP IN PARTICULAR HAS LATCHED ONTO. THE SOMEWHAT DEEPER LOW
ALONG WITH THE VERY STRONG ARCTIC HIGH SPREADING SOUTHEAST WILL
RESULT IN VERY STRONG WINDS DEVELOPING THIS AFTERNOON. INCREASING
LOW LEVEL COLD AIR ADVECTION AND SFC HEIGHT RISES FAVOR PRETTY GOOD
MIXING IN THE BOUNDARY LAYER...WHICH IS WHAT ALL MODEL FORECAST
SOUNDINGS ARE ADVERTISING. TAKING EVEN THE BEST CASE SCENARIO AND
ONE OF THE WEAKEST MODELS BUFKIT MOMENTUM TRANSFER VALUES SUPPORT
4-7 HOURS OF WIND GUSTS BETWEEN 35-40 MPH LATER THIS AFTERNOON AND
EVENING...WITH MORE AGGRESSIVE GFS/RAP SUPPORTING EVEN STRONGER
WINDS OVER A LONGER DURATION. SNOW HAS BEEN WET THUS FAR BUT WITH
TIME SHOULD SEE THE TRANSITION TOWARD DRIER/MORE BLOWABLE SNOW THIS
AFTERNOON FROM NORTH TO SOUTH AS THE COLUMN COOLS AND THE SNOW
LIQUID CONTENT DECREASES. BIGGEST UNCERTAINTY REVOLVES AROUND
REGARDING UPGRADE TO BLIZZARD WARNING WAS THE SNOW LIQUID CONTENT
AND PROBABILITY AND CONFIDENCE IS CERTAINLY HIGHER THE FARTHER NORTH
FROM I-80 THAT YOU GET...BUT EVEN AS FAR SOUTH AS I-80 FELT FAIRLY
CONFIDENT THAT WHITE OUT CONDITIONS COULD DEVELOP LATE THIS
AFTERNOON AND ESPECIALLY THIS EVENING. FARTHER WEST ACROSS NORTH
CENTRAL ILLINOIS FEEL THAT A BLIZZARD WARNING COULD EASILY BE
JUSTIFIED...BUT IN COORDINATION WITH MKX/DVN HAVE OPTED TO HOLD OFF
FOR NOW AS SNOW INTENSITY COULD BE DECREASING AS WINDS PICK UP.
QUITE POSSIBLE DAY SHIFT MAY NEED TO RE-ACCESS THIS AND AN UPGRADE
TO BLIZZARD WARNING FOR RFD AND POINTS WEST COULD OCCUR ON THE DAY
SHIFT.
OTHER BIG CHANGE TO FORECAST WAS TO ADD SLEET AND THEN DRIZZLE TO
THE FAR SOUTHEAST CWA. SFC TEMPS HAVE BEEN A BIT WARMER AND THE
FARTHER NORTH TRACK OF THE SFC LOW SHOULD KEEP LOW LEVEL WAA GOING
INTO EARLY AFTERNOON WITH AT LEAST THE THREAT OF MIXED
PRECIP...POSSIBLY TRANSITIONING OVER TO JUST DRIZZLE/SNIZZLE AS MID
LEVEL DRY SLOT OVERSPREADS THAT AREA REMOVING ICE NUCLEI FROM THE
CLOUDS LATE THIS AFTERNOON INTO THIS EVENING. THE WETTER SNOW SOUTH
OF I-80 SHOULD RESULT IN LESS SEVERE AND LESS IMPACTFUL
BLOWING/DRIFTING SNOW. GIVEN THE MARGINAL TEMPS AND POTENTIAL MIX
PRECIP HAVE CUT BACK ON ACCUMS IN THE FAR SOUTHEAST COUNTIES OF THE
CWA.
ACCUMULATING LAKE EFFECT POTENTIAL ACTUALLY LOOKS SOMEWHAT LESS
IMPRESSIVE THAN IT DID LAST NIGHT...AND IT WAS ALREADY LOOKING
MARGINAL. SOME SYSTEM SNOWS SHOULD LINGER INTO THIS EVENING BUT LAKE
CONTRIBUTIONS LOOK MINOR WITH LOW INVERSION HEIGHTS AND DECREASING
BOUNDARY LAYER RH AS THE THERMODYNAMICS IMPROVE EVER SO SLIGHTLY.
ANY LAKE ENHANCEMENT TO SNOW TOTALS SHOULD END UP BEING TRIVIAL.
FINALLY...GOING SNOWFALL TOTALS LOOK RIGHT ON TARGET AND MADE VERY
FEW CHANGES OTHER THAN IN SE AS NOTED ABOVE. A RESPECTABLY LARGE
SWATH OF A FOOT OR MORE OF SNOW STILL LOOKS LIKELY AND PROBABLY
CENTERED RELATIVELY CLOSE TO THE I-80 TO I-88/290 CORRIDORS.
ACTUALLY THINKING THAT MAX SNOWFALL TOTALS IN THE CWA COULD END UP
BEING ON THE HIGH END OF THE 10-14 INCH RANGE WITH LOCALIZED TOTALS
POTENTIALLY PUSHING A FOOT AND A HALF IF THE DEFO BAND IS INDEED AS
IMPRESSIVE AS SOME OF THE GUIDANCE WOULD SUGGEST. WHILE SNOWFALL
TOTALS WILL BE VERY IMPRESSIVE OVER MOST OF THE CWA...IT IS
IMPORTANT TO REMEMBER THE BLIZZARD WARNING IS ISSUED NOT FOR
SNOWFALL AMOUNTS BUT RATHER FOR VISIBILITY AND WINDS. THE CRITERIA
FOR BLIZZARD WARNING IS 3+ HOURS OF LESS THAN 1/4SM VSBY IN FALLING
AND/OR BLOWING SNOW ALONG WITH SUSTAINED WINDS OR FREQUENT GUSTS
OVER 35 MPH.
IZZI
&&
.LONG TERM...
MONDAY NIGHT THROUGH SATURDAY...
134 AM...FORECAST CONCERNS INCLUDE A CHANCE OF LIGHT SNOW MONDAY
NIGHT INTO TUESDAY...THEN A BETTER CHANCE FOR ACCUMULATING LIGHT
SNOW TUESDAY NIGHT INTO WEDNESDAY MORNING.
A RIDGE OF HIGH PRESSURE WILL BE MOVING SOUTHEAST OF THE AREA
MONDAY EVENING AS A WEAK WAVE MOVES ACROSS THE REGION MONDAY NIGHT.
FAIRLY LIGHT QPF FROM ALL THE MODELS WITH THIS WAVE BUT PLENTY COLD
ENOUGH FOR THE LOW QPF AMOUNTS TO POTENTIALLY FLUFF UP TO A HALF
INCH MONDAY NIGHT. WHILE TEMPS BY THIS TIME WILL LIKELY BE IN THE
SINGLE DIGITS OR LOW TEENS...CLOUD COVER AND WEAK WARM AIR ADVECTION
MAY ALLOW TEMPS TO HOLD STEADY OR RISE A FEW DEGREES OVERNIGHT.
NEXT WAVE QUICKLY SHIFTS SOUTHEAST ACROSS THE AREA BY TUESDAY
EVENING WITH QPF AMOUNTS BETWEEN ONE AND TWO TENTHS. THIS HAS BEEN
A FAIRLY CONSISTENT FEATURE ON THE MODELS AND IF THIS MATERIALIZES
AS ADVERTISED...A FEW INCHES OF SNOW WILL BE POSSIBLE. TIMING AND
LOCATION ALSO ARE A BIT UNCERTAIN...EARLIER COULD IMPACT THE TUESDAY
EVENING RUSH...LATER COULD IMPACT THE WEDNESDAY MORNING RUSH. BUT
GIVEN THE POTENTIAL FOR SOME ACCUMULATION...OPTED TO BUMP POPS UP TO
LIKELY FOR TUESDAY NIGHT.
HIGH PRESSURE THEN SETTLES SOUTH ACROSS THE MIDWEST AND LAKES REGION
WEDNESDAY INTO THURSDAY AND WITH IT...SOME VERY COLD AIR. WITH A
DEEP SNOWPACK BY THAT TIME AND DIMINISHING WINDS WEDNESDAY NIGHT
INTO THURSDAY...EXPECT MANY LOCATIONS TO DROP BELOW ZERO FOR LOWS
THURSDAY MORNING. THE AIRMASS MODIFIES/WARMS SOME THURSDAY BUT
STILL EXPECTING LOWS IN THE LOWER SINGLE DIGITS THURSDAY EVENING...
POSSIBLY BELOW ZERO BUT WARM AIR ADVECTION BY MORNING WITH
INCREASING SOUTHERLY WINDS MAY PUT THE BRAKES ON HOW LOW TEMPS FALL
THURSDAY NIGHT. STRONG SOUTHERLY WINDS CONTINUE INTO SATURDAY WITH
WARMING TEMPS...THAT WILL LIKELY BE MUTED SOME BY THE SNOWPACK. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* SNOW THRU THE PERIOD. VISIBILITIES GENERALLY AROUND 3/4SM...WITH
OCNL PERIODS OF VIS AS LOW AS 1/4SM POSSIBLE ESPECIALLY THIS
AFTERNOON.
* STRONG NORTHEAST WINDS SUNDAY...GUSTING UP TO 35 KT.
* BLOWING SNOW SUNDAY AND SUNDAY NIGHT.
* IFR/LIFR CIGS THRU THE PERIOD.
KREIN
//DISCUSSION...UPDATED 06Z...
LONG DURATION SNOW EVENT UNDERWAY AS LOW PRESSURE OVER KANSAS
MOVES EAST TO SOUTHERN INDIANA BY SUNDAY EVENING AS IT SLOWLY
STRENGTHENS. MOISTURE STREAMING NORTH FROM THE GULF WILL ALLOW
THIS SYSTEM TO PRODUCE MODERATE SNOW THROUGH SUNDAY EVENING...
BEFORE SLOWLY TAPERING OFF LATE SUNDAY EVENING AND EARLY MONDAY
MORNING. VISIBILITIES WILL LIKELY FLUCTUATE FROM TIME TO TIME
BUT PREVAILING VIS LIKELY TO BE AROUND 1/2SM FOR MUCH OF THE
EVENT.
AS THE GRADIENT STRENGTHENS SUNDAY MORNING...NORTHEAST WINDS
WILL INCREASE UP TO 20KTS WITH GUSTS 30-35KTS FOR MUCH OF THE
AFTERNOON AND EVENING. THESE STRONG WINDS WILL PRODUCE BLOWING
AND DRIFTING SNOW THAT MAY REDUCE VISIBILITIES UNDER 1/2SM AT
TIMES. THE WINDS WILL TURN MORE NORTHERLY SUNDAY EVENING AND
THEN BEGIN TO DIMINISH EARLY MONDAY MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH FOR SNOW/VIS THRU THE PERIOD.
* HIGH FOR WINDS/GUSTS THRU THE PERIOD.
* HIGH FOR BLOWING SNOW SUNDAY/SUNDAY NIGHT.
KREIN
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE LINGERING SNOW SHOWERS IN THE MORNING. CHANCE OF
SNOW AGAIN AFTER MIDNIGHT. MVFR CIGS/VIS LIKELY. IFR POSSIBLE.
TUESDAY...CHANCE SNOW. PERIODS OF MVFR CIGS/VIS LIKELY...IFR VSBY
POSSIBLE.
WEDNESDAY...SLIGHT CHANCE SNOW THROUGH EARLY EVENING. PERIODS OF
MVFR CIGS/VIS POSSIBLE. VFR/WX NIL OVERNIGHT.
THURSDAY...VFR/WX NIL.
FRIDAY...VFR/WX NIL.
MDB
&&
.MARINE...
315 AM CST
THE SFC LOW OVER THE PLAINS LOOKS TO BE DEEPENING A LITTLE FASTER
AND LOWER WHILE THE HIGH PRESSURE RIDGING OVER THE UPPER GREAT
LAKES IS TRENDING A LITTLE STRONGER. THIS COMBINATION WITH STRONG
COLD ADVECTION SETTING UP OVER THE LAKE TODAY...HAVE EXPANDED THE
GALE WARNING OVER THE ENTIRE OPEN WATERS OF LAKE MICHIGAN AS WELL
AS EXTENDING IN TIME...STARTING A LITTLE EARLIER...AT 15Z THIS
MORNING AND GOING A LITTLE LATER...TO 09Z TONIGHT. ALSO...HAVE
INCREASED GALES TO 40KT OVER THE SOUTHERN PORTIONS OF THE LAKE
WHERE THE PRESSURE GRADIENT AND PRESSURE FALLS ARE STRONGEST. AS
THE WINDS PICK UP TO GALE FORCE AND MUCH COLDER AIR FILTERS OVER
THE LAKE LATER TODAY...HEAVY FREEZING SPRAY WILL BE LIKELY...SO
HAVE ALSO ISSUED A HEAVY FREEZING SPRAY WARNING FROM 15Z THIS
MORNING TO 09Z TONIGHT. THE COLDER AIR WILL SPREAD OVER THE
NORTHERN PORTIONS OF THE LAKE EARLIER THAN THE SOUTHERN
PORTIONS...SO IT IS POSSIBLE THAT THE HEAVY FREEZING SPRAY
POTENTIAL MAY NOT REACH THE SOUTHERN PORTIONS OF THE LAKE UNTIL
THIS AFTERNOON...BUT WENT WITH ONE SEGMENT TO THE WARNING TO
COINCIDE WITH THE GALE WARNING TIMING. THE LOW SHOULD PUSH EAST
INTO THE MID ATLANTIC REGION BE MONDAY AFTERNOON...WHILE HIGH
PRESSURE SPREADS ACROSS THE MISSISSIPPI RIVER INTO THE WESTERN
GREAT LAKES REGION. THIS WILL LEAD TO SUBSIDING WINDS AND
WAVES...ESPECIALLY AS WEAK HIGH PRESSURE PRESSURE CROSSES THE LAKE
MONDAY NIGHT AND TUESDAY.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING...ILZ005-ILZ006-ILZ011-ILZ012-ILZ013-ILZ014-
ILZ020-ILZ022 UNTIL 2 PM SUNDAY.
BLIZZARD WARNING...ILZ005-ILZ006-ILZ011-ILZ012-ILZ013-ILZ014-
ILZ020-ILZ022...2 PM SUNDAY TO MIDNIGHT MONDAY.
WINTER STORM WARNING...ILZ003-ILZ004-ILZ008-ILZ010-ILZ019-ILZ021-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL MIDNIGHT MONDAY.
IN...BLIZZARD WARNING...INZ001...2 PM SUNDAY TO MIDNIGHT MONDAY.
WINTER STORM WARNING...INZ001 UNTIL 2 PM SUNDAY.
WINTER STORM WARNING...INZ002-INZ010-INZ011-INZ019 UNTIL
MIDNIGHT MONDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878...9 AM SUNDAY TO 3 AM MONDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 AM SUNDAY TO
3 AM MONDAY.
SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 9 AM SUNDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS MARQUETTE MI
419 AM EST SUN FEB 1 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM EST SAT JAN 31 2015
THIS AFTERNOON THROUGH SUNDAY...HIGH PRESSURE SLIDING ACROSS CENTRAL
CANADA THIS AFTERNOON HAS ALLOW NORTHERLY FLOW TO INCREASE ACROSS
MUCH OF THE UPPER GREAT LAKES REGION. THIS NORTHERLY FLOW COUPLED
WITH 850MB TEMPERATURES COOLING TO AROUND -18C TO -20C HAS ALLOWED
LAKE EFFECT SNOW TO DEVELOP AHEAD OF THE SURFACE HIGH PRESSURE
SYSTEM. INITIALLY...DEEPER MOISTURE WILL LINGER INTO THE EARLY
EVENING HOURS ALLOWING BETTER SNOW GROWTH WITH A THICKER SNOW GROTH
AREA WITHIN THE DGZ. RUC SOUNDINGS SHOW INVERSION HEIGHTS BETWEEN
4KFT AND 5KFT THIS AFETERNOON WHICH IS ALSO VERIFIED BY THE MQT VAD
WIND PROFILE THIS AFETERNOON. THIS HAS ALLOWED GOOD SNOWFLAKE SIZE
THIS AFTERNOON RESULTING IN A QUICK INCH OR TWO OF FLUFFY SNOW ON A
NORTH TO NORTHWESTERLY WIND. DRY AIR REMAINS JUST TO THE NORTH OF
THE AREA THIS AFTERNOON...HOWEVER...THIS IS EXPECTED TO SHIFT
FARTHER SOUTH AROUND 00Z/01 AS INVERSION HEIGHTS BEGIN TO FALL TO
AROUND 3KFT. THIS SHOULD HELP TO REDUCE SNOWFALL RATES THIS EVENING
INTO THE OVERNIGHT HOURS.
AS THE SURFACE RIDGE EXPANDS TO THE NORTH OF LAKE SUPERIOR EXPECT
WINDS TO SHIFT TO THE NORTH AND NORTHEAST SHIFTING THE SNOWBANDS TO
THE NORTH TO NORTHEAST WIND FAVORED SNOW BELTS. AGAIN...REDUCED
MOISTURE...LOWERED INVERSION HEIGHTS ALONG WITH ANTICYCLONIC FLOW
WILL HELP TO KEEP SNOWFALL TOTALS IN CHECK ACROSS THE U.P. WITH UP
TO 2 INCHES EXPECTED ALONG THE NORTH TO NORTHEAST WIND FAVORED SNOW
BELTS. AS THE SURFACE RIDGE CENTER SHIFTS INTO THE NORTHERN PLAINS
ON SUNDAY EXPECT WINDS TO SHIFT TO A MORE NORTHERLY DIRECTION.
TEMPERATURES ALOFT WILL REMAIN COLD ENOUGH AND LOW LEVEL MOISTURE
OFF LAKE SUPERIOR WILL KEEP LAKE EFFECT SNOW IN NORTHERLY WIND
FAVORED LOCATIONS...WITH AROUND AN INCH ACCUMULATION EXPECTED IN
THESE AREAS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 418 AM EST SUN FEB 1 2015
GREATEST RISK OF HAZARDOUS WEATHER IN THE EXTENDED IN NW WIND
SNOWBELTS WED THROUGH WED NIGHT AND POSSIBLY ACROSS THE KEWEENAW
PENINSULA LATE MON INTO MON NIGHT. MAY SEE WIND CHILL VALUES NEAR
ADVISORY CRITERIA THU MORNING.
MON MORNING WILL SEE ONGOING LES IN THE N TO NW SNOWBELTS AS 850MB
TEMPS WILL BE AROUND -22C. A SFC RIDGE WILL BE OVER WRN LAKE
SUPERIOR BY 12Z MON...BUT WILL BE PUSHED QUICKLY E AS A SFC TROUGH
MOVES/DEVELOPS INTO THE AREA ON MON. WITH THE TROUGH MOVING INTO NRN
LAKE SUPERIOR AS THE RIDGE SUPPRESSES SOUTHWARD...W TO WSW LOW LEVEL
FLOW RESULTS BY MON AFTERNOON AND CONTINUES UNTIL LATE MON NIGHT
WHEN ADDITIONAL ENERGY IS ADDED TO THE TROUGH /PUSHING IT SLIGHTLY
SE/ AND FLOW VEERS TO A WNW DIRECTION. THE FLOW DIRECTION FAVORS THE
KEWEENAW FOR THE BEST SNOW...BUT EXACTLY HOW LONG THE STRONGER
BAND/S/ LINGER IN ANY LOCATION IS MORE UNCERTAIN. AT THIS
TIME...MODEL WIND FIELDS DO SUPPORT THE IDEA OF SEEING A FEW INCHES
OF SNOW OVER THE KEWEENAW...ESPECIALLY THE NRN/WRN KEWEENAW...LATE
MON INTO TUE MORNING. THIS IS BACKED UP BY MODEL QPF FROM THE NAM
AND GFS. THE 00Z/01 NAM HAS UP TO 0.15 INCHES...WHICH WOULD BE
UNDERDONE IF THE SCENARIO DOES OCCUR...AND THE 00Z/01 GFS HAS 0.07
INCHES OF QPF...WHICH WOULD BE WELL UNDERDONE DUE TO MODEL
RESOLUTION.
WNW FLOW LES IS EXPECTED TUE INTO TUE NIGHT AS THE SFC TROUGH
LINGERS...BUT A COLD FRONT/TROUGH WILL MOVE IN WITH A SYSTEM LATE
TUE NIGHT AND WED AND WILL BRING EVEN COLDER AIR TO THE REGION.
MODERATE TO LOCALLY HEAVY SNOW IS PROBABLE ALONG THE FRONT WHILE IN
THE NW WIND SNOWBELTS. BEHIND THE FRONT...MODERATE LES WILL CONTINUE
AT LEAST INTO WED NIGHT AS 850MB TEMPS WILL BE AS LOW AS -27C. THERE
IS UNCERTAINTY AS TO WHEN CONDITIONS MODIFY ON THE BACK SIDE OF THE
SYSTEM AS THE ECMWF BRINGS SIGNIFICANTLY WARMER AIR WITH WSW FLOW BY
12Z THU WHILE THE GFS IS ABOUT 12 HOURS SLOWER IN DOING SO. WITH
THAT COLD OF AN AIRMASS...WE WILL BE LOOKING AT SMALL SNOW FLAKES
THAT ARE EFFICIENT AT REDUCING VIS. COULD SEE HEADLINE WORTHY
CONDITIONS DURING THIS TIME PERIOD...MAINLY IN THE NW WIND SNOWBELTS.
LOOKS LIKE WSW FLOW AND WAA CONTINUE THROUGH THU NIGHT...BUT MODELS
VARY SIGNIFICANTLY FROM RUN TO RUN AND FROM MODEL TO MODEL AFTER
THAT...SO WILL JUST USE A CONSENSUS APPROACH FOR FRI THROUGH SAT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1155 PM EST SAT JAN 31 2015
MVFR CONDITIONS WILL CONTINUE FOR ALL SITES THIS FORECAST PERIOD
WITH NORTHEAST UPSLOPE WINDS. SNOW SHOWERS WILL BE PERIODIC AT SAW
AND CMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 340 PM EST SAT JAN 31 2015
A COLD FRONT THAT SHIFTED SOUTH AND EAST OF THE AREA THIS AFTERNOON
ALONG WITH A DECENT PRESSURE GRADIENT ON THE BACK SIDE WILL ALLOW A
FEW GUSTS TO REACH 35KTS THIS AFTERNOON AND EVENING. MUCH LIGHTER
WINDS WILL PREVAIL SUNDAY AS HIGH PRESSURE DRIFTS ACROSS THE UPPER
GREAT LAKES REGION. LOW PRESSURE AND ASSOCIATED COLD FRONT WILL
APPROACH THE AREA MONDAY NIGHT AND THEN SWEEP THROUGH THE AREA
TUESDA NIGHT AND WEDNESDAY. ON THE BACK SIDE OF THIS SYSTEM...WINDS
WILL INCREASE FROM THE NORTHWEST WEDNESDAY AFTERNOON THROUGH
THURSDAY...WITH GALE FORCE GUSTS TO 35 KNOTS POSSIBLE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KEC
LONG TERM...TITUS
AVIATION...07
MARINE...KEC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1156 PM EST SAT JAN 31 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 340 PM EST SAT JAN 31 2015
THIS AFTERNOON THROUGH SUNDAY...HIGH PRESSURE SLIDING ACROSS CENTRAL
CANADA THIS AFTERNOON HAS ALLOW NORTHERLY FLOW TO INCREASE ACROSS
MUCH OF THE UPPER GREAT LAKES REGION. THIS NORTHERLY FLOW COUPLED
WITH 850MB TEMPERATURES COOLING TO AROUND -18C TO -20C HAS ALLOWED
LAKE EFFECT SNOW TO DEVELOP AHEAD OF THE SURFACE HIGH PRESSURE
SYSTEM. INITIALLY...DEEPER MOISTURE WILL LINGER INTO THE EARLY
EVENING HOURS ALLOWING BETTER SNOW GROWTH WITH A THICKER SNOW GROTH
AREA WITHIN THE DGZ. RUC SOUNDINGS SHOW INVERSION HEIGHTS BETWEEN
4KFT AND 5KFT THIS AFETERNOON WHICH IS ALSO VERIFIED BY THE MQT VAD
WIND PROFILE THIS AFETERNOON. THIS HAS ALLOWED GOOD SNOWFLAKE SIZE
THIS AFTERNOON RESULTING IN A QUICK INCH OR TWO OF FLUFFY SNOW ON A
NORTH TO NORTHWESTERLY WIND. DRY AIR REMAINS JUST TO THE NORTH OF
THE AREA THIS AFTERNOON...HOWEVER...THIS IS EXPECTED TO SHIFT
FARTHER SOUTH AROUND 00Z/01 AS INVERSION HEIGHTS BEGIN TO FALL TO
AROUND 3KFT. THIS SHOULD HELP TO REDUCE SNOWFALL RATES THIS EVENING
INTO THE OVERNIGHT HOURS.
AS THE SURFACE RIDGE EXPANDS TO THE NORTH OF LAKE SUPERIOR EXPECT
WINDS TO SHIFT TO THE NORTH AND NORTHEAST SHIFTING THE SNOWBANDS TO
THE NORTH TO NORTHEAST WIND FAVORED SNOW BELTS. AGAIN...REDUCED
MOISTURE...LOWERED INVERSION HEIGHTS ALONG WITH ANTICYCLONIC FLOW
WILL HELP TO KEEP SNOWFALL TOTALS IN CHECK ACROSS THE U.P. WITH UP
TO 2 INCHES EXPECTED ALONG THE NORTH TO NORTHEAST WIND FAVORED SNOW
BELTS. AS THE SURFACE RIDGE CENTER SHIFTS INTO THE NORTHERN PLAINS
ON SUNDAY EXPECT WINDS TO SHIFT TO A MORE NORTHERLY DIRECTION.
TEMPERATURES ALOFT WILL REMAIN COLD ENOUGH AND LOW LEVEL MOISTURE
OFF LAKE SUPERIOR WILL KEEP LAKE EFFECT SNOW IN NORTHERLY WIND
FAVORED LOCATIONS...WITH AROUND AN INCH ACCUMULATION EXPECTED IN
THESE AREAS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 PM EST SAT JAN 31 2015
...NW FLOW LES AND POOR VSBY DUE TO BLSN/DRSN MAY LEAD TO HEADLINES
WEDNESDAY INTO THURSDAY...
COLD WEEK IN STORE AS A BUILDING RIDGE ALOFT OVER WESTERN NORTH
AMERICA RESULTS IN MEAN TROUGHING CENTERED OVER HUDSON BAY EXTENDING
OVER GREAT LAKES AND NORTHEAST CONUS. PATTERN DOES NOT HOLD MUCH
OPPORTUNITY FOR WIDESPREAD SNOW. BEST CHANCE OF THAT MAY ACTUALLY
COME FRIDAY. OTHERWISE...LAKE EFFECT SNOW AND BLOWING/DRIFTING SNOW
WITH POOR VISIBILITY WILL BE MAIN ISSUE. APPEARED THAT MODERATION IN
THE CHILL WOULD START TO DEVELOP BY NEXT WEEKEND...BUT RECENT RUNS OF
THE ECMWF/GFS HAVE TRENDED TOWARD MORE TROUGHING AND COLDER
TEMPERATURES. WILL HAVE TO WAIT AND SEE IF THIS IS A LASTING TREND.
HIGH IMPACT WEATHER THAT JUSTIFIES ANY TYPE OF HEADLINES THROUGH THE
EXTENDED LIKELY WILL BE TIED TO THE LAKE EFFECT SNOW AND POOR VSBY.
BEST CHANCE OF SEEING HEADLINES WILL BE WEDNESDAY INTO THURSDAY FOR
NW FLOW AREAS NEAR LK SUPERIOR. WILL ALSO GIVE AN HONORABLE MENTION
FOR WSW FLOW ON TIP OF KEWEENAW PENINSULA LATE MONDAY INTO MONDAY
NIGHT...AS THOUGH THIS IS A VERY LOW PROBABILITY EVENT IT COULD NEED
A HEADLINE IF IT OCCURS. SUPPOSE THERE ALSO COULD BE NEED FOR WIND
CHILL ADVYS MONDAY MORNING AND AGAIN THURSDAY MORNING...BUT ATTM IT
DOES NOT LOOK LIKE A SURE THING THANKS TO LIGHT WINDS AND/OR MORE IN
TERMS OF LAKE MODERATION ON TEMPS.
NO REAL HAZARDOUS WEATHER EXPECTED SUNDAY NIGHT INTO MONDAY MORNING
WITH DIMINISHING WINDS AND WEAK LES AS INVERSIONS ARE WELL BLO 5KFT.
PLENTY COLD WITH TEMPS AT INVERION TOP BLO -20C. SLR/S ON THE
HIGHER/FLUFFY SIDE SO A COUPLE OF INCHES OF SNOW IS POSSIBLE FOR
MAINLY NCNTRL UPR MICHIGAN. GIVEN THE WEAKENING WINDS...MESOLOW
FORMATION REMAINS POSSIBLE WHICH WOULD ENHANCE CONVERGENCE AND ADD
TO THE SNOW AMOUNTS. HIGHEST PROBABILITY OF THIS OCCURRING WOULD BE
BTWN MARQUETTE AND PICTURED ROCKS LAKESHORE...SO LOOKING AT AU TRAIN
AND MUNISING AREAS. AWAY FM THE LES...TEMPS FALL WELL BLO ZERO LATE
SUNDAY NIGHT INTO MONDAY MORNING...BUT WITH LIGHT WINDS AND SOME
LAKE MODERATION/LAKE EFFECT CLOUDS...WIND CHILLS WILL MAINLY STAY
HIGHER THAN 20 BLO. SFC TROUGH CROSSING THE AREA MONDAY MORNING
SHOULD RESULT IN WINDS BECOMING MORE WESTERLY WHICH WILL DISRUPT THE
LES OVER ALGER COUNTY BUT WILL INCREASE IT ON THE KEWEENAW PENINSULA.
WESTERLY CONVERGENT FLOW LES HAS POTENTIAL TO DROP SEVERAL INCHES OF
SNOW LATE MONDAY AFTN INTO MONDAY NIGHT OVER NORTHERN SECTIONS OF
THE KEWEENAW. SOUNDINGS SHOW INVERSION AT LEAST TO 5KFT AND
DISTURBANCE ROTATING THROUGH AHEAD OF ANOTHER TROUGH MOVING OVER
UPPER GREAT LAKES ON TUESDAY MORNING. NAM SHARPER WITH TROUGH AND
BACKS WINDS ENOUGH TO KEEP HEAVIER LES OFFSHORE OF KEWEENAW. GFS AND
ECMWF NOT AS BACKED WITH WINDS. WILL CONTINUE TO SHOW HIGHEST POPS
ON THE KEWEENAW AND MENTION IN HAZARDOUS WEATHER OUTLOOK.
TROUGH SINKS OVER NORTHERN UPR MICHIGAN THROUGH DAY ON TUESDAY...
SPREADING THE LES TO NW FLOW SNOW BELTS OF NORTHERN UPR MICHGAN...
ESPECIALLY BY TUESDAY NIGHT. SOUNDINGS SHOW INVERSIONS UP TO 6-8 KFT
IN WAKE OF THE TROUGH WITH AS H85 TEMPS DROP TO -25C BY DAYBREAK ON
WEDNESDAY. SETUP WILL THEN FAVOR A PUSH OF HEAVIER LES AS THE MAIN
COLD FRONT MOVES THROUGH TUESDAY NIGHT INTO WEDNESDAY MORNING WITH
CONDITIONS QUICKLY TRANSITIONING TO SMALL SNOWFLAKE/LOW VSBY LES
REGIME FOR THE NORTHWEST WIND SNOW BELTS WEDNESDAY AFTN INTO
WEDNESDAY NIGHT. BLYR WINDS INCREASE THROUGH WEDNESDAY TO 25-30 KTS
SO BLSN AND DRSN WILL ALSO BECOME A CONCERN IN OPEN AREAS NEAR LK
SUPERIOR AND ESPECIALLY WHERE ICE IS BUILT UP ALONG THE SHORELINE.
AWAY FM THE LES THE MAIN THEME WILL BE COLD. TEMPS ON WEDNESDAY WILL
ONLY STRUGGLE INTO THE SINGLE DIGITS ABOVE ZERO WITH WIND CHILL
READINGS 10 TO 20 BLO ZERO. AS TEMPS FALL OFF WELL BLO ZERO ON
WEDNESDAY NIGHT OVER WESTERN UPR MICHIGAN...MAY SEE WIND CHILL
READINGS MAY COME CLOSE TO ADVY INTO THURSDAY MORNING. WINDS WILL BE
SLACKENING BY THIS TIME THOUGH...ESPECIALLY OVER INTERIOR SECTIONS
OF CWA. A BIT OF MODERATION ON THURSDAY FOR HIGHS WITH READINGS
NEARING 10 DEGREES OR REACHING THE LOWER TEENS. BLYR WINDS BACK SW
LATER THURSDAY INTO THURSDAY NIGHT AS HIGH PRESSURE RIDGE SETTLES FM
THE MIDDLE MISSISSIPPI RIVER VALLEY TO THE OHIO VALLEY. EXPECT THE
LES TO SHIFT OFFSHORE BY THURSDAY NIGHT. SINCE UPPER LAKES WILL BE
AHEAD OF ANOTHER SFC TROUGH CROSSING SOUTH CENTRAL CANADA...EXPECT
CLOUDS TO BE ON THE INCREASE WITH EVEN A POSSIBILITY OF LGT SNOW OR
FLURRIES. THUS...TEMPS SHOULD NOT CRASH TOO MUCH ON THURSDAY NIGHT.
STRONGER COLD FRONT WITH ANOTHER PUSH OF COLDER AIR EXPECTED TO
ARRIVE FRIDAY NIGHT INTO SATURDAY. SHORTWAVE/CONVERGENCE ALONG THE
SFC-H85 FRONT AND UPPER DIVERGENCE ON NOSE OF H3 JET STREAK COMBINE
TO SPREAD SWATH OF SNOW OVER MOST OF UPR MICHIGAN FRIDAY AFTN INTO
FRIDAY EVENING. TIMING MAY SHIFT AROUND SOME THOUGH CONSIDERING THIS
SOLUTION IN THE MODELS IS NEWER DEVELOPMENT. LOW CHANCE POPS WILL
WORK FOR NOW WITH THE SNOW ALONG THE COLD FRONT AND THEN MORE LOW
CHANCE POPS FOR NEXT SATURDAY WITH DEVELOPING NE FLOW LES IN WAKE OF
THE FRONT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1155 PM EST SAT JAN 31 2015
MVFR CONDITIONS WILL CONTINUE FOR ALL SITES THIS FORECAST PERIOD
WITH NORTHEAST UPSLOPE WINDS. SNOW SHOWERS WILL BE PERIODIC AT SAW
AND CMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 340 PM EST SAT JAN 31 2015
A COLD FRONT THAT SHIFTED SOUTH AND EAST OF THE AREA THIS AFTERNOON
ALONG WITH A DECENT PRESSURE GRADIENT ON THE BACK SIDE WILL ALLOW A
FEW GUSTS TO REACH 35KTS THIS AFTERNOON AND EVENING. MUCH LIGHTER
WINDS WILL PREVAIL SUNDAY AS HIGH PRESSURE DRIFTS ACROSS THE UPPER
GREAT LAKES REGION. LOW PRESSURE AND ASSOCIATED COLD FRONT WILL
APPROACH THE AREA MONDAY NIGHT AND THEN SWEEP THROUGH THE AREA
TUESDA NIGHT AND WEDNESDAY. ON THE BACK SIDE OF THIS SYSTEM...WINDS
WILL INCREASE FROM THE NORTHWEST WEDNESDAY AFTERNOON THROUGH
THURSDAY...WITH GALE FORCE GUSTS TO 35 KNOTS POSSIBLE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 5 AM EST SUNDAY FOR LSZ264-
266-267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KEC
LONG TERM...JLA
AVIATION...07
MARINE...KEC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
345 AM CST SUN FEB 1 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 221 AM CST SUN FEB 1 2015
MAIN FORECAST CONCERN IS ADDITIONAL SNOW ACCUMULATION THIS MORNING
AND NEAR-BLIZZARD CONDITIONS EXPECTED LATE THIS MORNING AND MUCH
OF THE AFTERNOON.
LATEST RADAR SCANS SHOWS THAT THE SNOW IS BEGINNING TO WANE
OVERALL. SOME EMBEDDED STRONGER SNOW BANDS ARE PRESENT NEAR
SCHUYLER/NORTH BEND WITH ANOTHER EHANCED AREA DRIFTING NORTHEAST
TO THE OMAHA/CB METRO AREA. METARS ARE SHOWING VISIBILITIES
GENERALLY 1 TO 2 MILES. WE DID HEAR OF ONE REPORT OF THUNDER...BUT
NEVER DID SEE THAT SHOW UP IN THE LIGHTNING DETECTION NET. THUS
FAR SNOW AMOUNTS HAVE BEEN AVERAGING 4 TO 9 INCHES IN THE WINTER
STORM WARNING AREA. MANY AREAS PROBABLY WON`T ACHIEVE THE WINTER
STORM CRITERIA AMOUNT OF 8 INCHES. BUT...WE FEEL THE WINTER STORM
WARNING REMAINS JUSTIFIED DUE TO THE EXTREMELY POOR ROAD
CONDITIONS BEING REPORTED AND THE EXPECTED NEAR-BLIZZARD
CONDITIONS POSSIBLE TODAY WHEN THE WINDS KICK IN. FOR THE
REMAINDER OF THIS MORNING...MOISTURE PROFILES REMAIN DEEP AND
STILL WELL LOCATED WITHIN THE DENDRITIC GROWTH ZONE. THUS SNOW
PRODUCTION REMAINS GOOD...THOUGH OVERALL SYSTEM LIFT IS PULLING
OUT TO THE NORTHEAST. FOR NOW THROUGH THIS AFTERNOON ANOTHER 1 TO
3 INCHES APPEARS LIKELY ACROSS THE COUNTY WARNING AREA WITH THE
HIGHEST AMOUNTS FOCUSED ACROSS EAST-CENTRAL NEBRASKA AND WESTERN
IOWA.
AS OF 9Z WINDS HAVE ALREADY PICKED UP AT OFK/LCG/ONL AND EXPECT
ALL AREAS TO BE VERY WINDY BY LATE THIS MORNING. RUC SOUNDINGS
SUGGEST DECENT MIXING MAY OCCUR THIS AFTERNOON AND WIND GUSTS OVER
40 MPH AREN`T OUT OF THE QUESTION. NOT SURE IF THE STRONGEST WINDS
WILL BE SUSTAINED LONG ENOUGH ALONG WITH LOW VISIBILITIES TO
NECESSITATE A BLIZZARD WARNING. CONDITIONS WILL SURELY BE VERY
POOR...THUS WE ADDED NEAR-BLIZZARD WORDING TO THE LATEST WINTER
STORM WARNING UPDATE. THE SNOW SHOULD BE FINISHED JUST AFTER
SUNSET THIS EVENING AND WINDS WILL STEADILY DECREASE OVERNIGHT AS
WEAK SURFACE HIGH PRESSURE SETTLES IN OVER THE AREA. DECIDED TO
LOWER OVERNIGHT LOWS A FEW DEGREES GIVEN SIGNIFICANT SNOW COVER IN
PLACE.
LOOKS LIKE DRY WEATHER FOR MONDAY AND MONDAY NIGHT. BY TUESDAY A
WEAK CLIPPER SYSTEM TRACKS ACROSS NORTHEAST NEBRASKA AND NORTHWEST
IOWA. SOME LIGHT SNOW MAY OCCUR...OPTED FOR LOW CHANCES FOR NOW.
AS THIS FEATURE MOVES EAST IT STRENGTHENS AND OUR FAR NORTHEASTERN
COUNTIES COULD PICK UP A COUPLE INCHES OF SNOW DURING THE DAY ON
TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 221 AM CST SUN FEB 1 2015
NORTHWEST FLOW ALOFT WILL CONTINUE THROUGH THE END OF THE WEEK
BEFORE A MORE ZONAL FLOW PATTERN SETS UP BY SATURDAY. ONE
SIGNIFICANT SHORTWAVE ROLLING THROUGH THE FLOW WILL BRING ANOTHER
CHANCE FOR SNOW TUESDAY NIGHT AND WEDNESDAY WITH COLDER HIGH
PRESSURE SETTLING INTO THE PLAINS FOLLOWING SHORTWAVE. TIMING AND
TRACK OF SNOW WITH THIS SHORTWAVE IS STILL IN QUESTION...BUT MODELS
SEEM TO BE COMING TOGETHER SOMEWHAT IN SHOWING MUCH OF EASTERN
NEBRASKA AND SOUTHWEST IOWA GETTING LIGHT SNOW AT SOME POINT TUESDAY
NIGHT OR WEDNESDAY. AMOUNTS SHOULD REMAIN IN THE INCH OR TWO RANGE
GIVEN LOWER MOISTURE CONTENT AND PROGRESSIVE MOVEMENT. LOWS TUESDAY
NIGHT IN THE TEENS WILL ONLY GAIN A FEW DEGREES INTO THE 20S
WEDNESDAY GIVEN CLOUDS/PRECIP AND A SWITCH TO NORTHERLY WINDS.
COLDER AIR SETTLING SOUTH BEHIND SHORTWAVE WILL GIVE US A COLD START
THURSDAY MORNING WITH LOWS IN THE SINGLE DIGITS...WITH SOME SUB-ZERO
READINGS LIKELY.
A QUICK REBOUND STILL LOOKS ON TRACK THURSDAY WITH WINDS BECOMING
SOUTHERLY...WHICH CONTINUE FRIDAY AND SATURDAY. THUS A SLIGHT
WARMING TREND IS FORECAST...CLIMBING FROM THE 20S THURSDAY TO THE
30S AND PERHAPS LOWER 40S FRIDAY AND SATURDAY.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 518 PM CST SAT JAN 31 2015
WINTER EVENT WILL IMPACT THE TAF SITES THROUGH MOST OF THE PERIOD.
IFR AND OCCASIONALLY LIFR CONDITIONS WITH SNOW AT ALL TAF SITES
WITH VISIBILITIES RANGING FROM 1/2 TO 1 1/2 MILES MOSTLY. WINDS
REMAIN LIGHT FROM THE EAST OR SOUTHEAST INITIALLY. WINDS WILL
CONTINUE TO BACK BECOMING NORTHEAST...THEN NORTH AND SUBSTANTIALLY
INCREASING BY 11-13Z TO 22 TO 35 KNOTS. AT THAT TIME...SNOW AND
BLOWING SNOW WILL CONTINUE TO REDUCE VISIBILITY THROUGH MUCH OF
THE DAY SUNDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ011-
016-017-030-031-090>093.
WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ012-015-
018-032>034-042>045-050>053-065>068-078-088-089.
IA...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR IAZ043-055-
056-069-080-091.
WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR IAZ079-090.
&&
$$
SHORT TERM...PEARSON
LONG TERM...DERGAN
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1034 PM CST SAT JAN 31 2015
.UPDATE...
ISSUED AT 1029 PM CST SAT JAN 31 2015
AFTER COORDINATION WITH SURROUNDING WFOS AND GETTING A COUPLE OF
NEW SNOWFALL REPORTS OF 4 TO 5 INCHES IN THE FAIRBURY...WILBER AND
LINCOLN AREAS...OPTED TO EXPAND THE WINTER STORM WARNING. SNOWFALL
RATES HAVE DEFINITELY PICKED UP IN THE I80 CORRIDOR WHICH WILL
HELP BRING TOTALS UP JUST SLIGHTLY MORE. HEAVY SNOW WILL BE
COMPACTING...BUT IT`S STILL ACCUMULATING AND WILL PUSH US CLOSER
TO THE 8 INCH CRITERIA IN A FEW AREAS. ALSO...WITH THE INCREASING
WINDS...FELT MORE COMFORTABLE GETTING A HEADLINE UPGRADE OUT
DURING THE EVENING NEWS RATHER THAN WAITING UNTIL THE OVERNIGHT
HOURS.
UPDATE ISSUED AT 920 PM CST SAT JAN 31 2015
WINTER HAS RETURNED. AS EXPECTED...00Z SUBJECTIVE UPPER AIR
ANALYSIS REVEALED A SIGNIFICANT AMOUNT OF MOISTURE WITH PW VALUES
ABOUT 210-280% ABOVE NORMAL. 500MB HEIGHT FALLS RANGED FROM 40 TO
80 METERS ACROSS THE REGION...AND OVERALL THE AREA REMAINS WITHIN
THE ENTRANCE REGION OF A BROAD UPPER LEVEL JET STREAK TO OUR
NORTH.
SNOW CONTINUES AT THIS TIME...AND WILL DO SO THROUGH MOST OF
SUNDAY...ALTHOUGH THE INTENSITY WILL BE WINDING DOWN ON SUNDAY.
THE SNOW SO FAR HAS BEEN A VERY HEAVY WET SNOW WITH SNOWFALL
RATIOS WELL BELOW 10:1. TEMPS HAVE REMAINED JUST ABOVE FREEZING IN
MOST AREAS THIS EVENING...WHICH IS LIKELY CONTRIBUTING TO ROAD
CONDITIONS BECOMING HAZARDOUS...PERHAPS MORESO THAN EXPECTED.
WHILE WINDS REMAIN LIGHT CURRENTLY LESS THAN 10 KNOTS IN MOST
AREAS...THEY ARE BACKING AND BEGINNING TO INCREASE IN NORTHEAST
NEBRASKA AS LOW PRESSURE BEGINS TO MOVE THROUGH CENTRAL KANSAS.
WINDS WILL SUBSTANTIALLY INCREASE BY 12Z AS THE LOW PRESSURE
CENTER MOVES ACROSS THE KC AREA...WHICH WILL THEN CREATE AREAS OF
BLOWING SNOW.
REGARDING SNOWFALL AMOUNTS...WE CURRENTLY HAVE 5 TO 9 INCHES
FORECAST WITH HIGH END WINTER WEATHER ADVISORIES AND WARNINGS IN
EFFECT AND THAT TREND SEEMS OK. THE HEAVY WET SNOW IS COMPACTING
QUITE A BIT ON THE GROUND. HAVE UPPED AMOUNTS JUST SLIGHTLY BASED
ON REPORTS. THUS...THIS WILL LIKELY END UP ON THE HIGH END OF THE
ADVISORY CATEGORY. HAVE ALSO CONSIDERED UPGRADING TO A WINTER
STORM WARNING TO ACCOUNT FOR THE BLOWING SNOW THAT WILL BE TAKING
PLACE ON SUNDAY...WITH GUSTS EASILY APPROACHING 40 MPH. WILL HAVE
TO SEE HOW VISIBILITIES RESPOND TO THAT AS IT MAY END UP IN NEAR
BLIZZARD CONDITIONS IN OUTLYING REMOTE AREAS ACROSS EASTERN
NEBRASKA. WILL DEFER THAT TO THE NEXT FORECAST ONCE WE GET MORE
MODEL DATA IN.
AS A SIDE NOTE...WE WILL BREAK WATER EQUIVALENT RECORDS AT BOTH
LINCOLN AND OMAHA FOR JAN 31.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 325 PM CST SAT JAN 31 2015
SNOW AND HEADLINES ARE THE MAIN PROBLEMS IN THE SHORT TERM AND HAVE
KEPT PRIMARY FOCUS IN THE NEXT 24-30 HOURS.
A 90 KNOT JET MAX WAS ON THE FRONT SIDE OF THE TROUGH ACROSS THE
SOUTHWEST US AT 12Z. ANOTHER AREA OF STRONG WINDS AT 300 MB WAS FROM
NORTHERN MINNESOTA INTO THE OHIO VALLEY. LATEST WATER VAPOR IMAGERY
AND RECENT RAP MODEL INITIALIZATIONS SHOW A CLOSED LOW DROPPING
SOUTHWARD ACROSS BAJA. A MID LEVEL TROUGH WAS LOCATED FROM WESTERN
NEBRASKA INTO EASTERN COLORADO AND ANOTHER WAVE WAS DROPPING
SOUTHEAST FROM MONTANA. A 12 HOUR 500 MB HEIGHT FALL MAX OF ABOUT
130 METERS WAS OVER MONTANA AND ANOTHER AROUND 100 METERS WAS NEAR
THE MEXICO/NEW MEXICO BORDER. SO THIS IS A FAIRLY COMPLEX SETUP...
WITH SOME PHASING OF THE NORTHERN AND SOUTHERN STREAMS EXPECTED
TONIGHT.
MOISTURE HAS BEEN RETURNING OVER THE CENTRAL PLAINS WITH AREAS OF
SNOW OR A MIX OF RAIN AND SNOW. WILL MAKE SOME MINOR CHANGES TO
HEADLINES...ADDING A FEW COUNTIES TO THE WARNING IN THE NORTH.
IMPRESSIVE MOISTURE (850-700 MB SPECIFIC HUMIDITY VALUES 3-4 G/KG
AT 6 PM THIS EVENING...FALLING TO 2-3 G/KG BY 12Z SUNDAY) ALONG
WITH GOOD FORCING SHOULD ALLOW FOR SNOW AMOUNTS FROM ABOUT 4 TO 9
INCHES IN MOST OF THE FORECAST AREA. HIGHEST SNOW AMOUNTS EXPECTED
NORTH AND EAST. AS COLDER AIR SINKS IN FROM THE NORTH BEHIND THE
COLD FRONT (WHICH EXTENDED FROM WISCONSIN BACK INTO SOUTHWEST
NEBRASKA EARLY THIS AFTERNOON)...TEMPERATURES WILL FALL AND ROADS
WILL START TO ICE UP/BECOME SNOW COVERED AND SLICK. TEMPERATURES
SHOULD START SLIDING TONIGHT AND CONTINUE TO DROP THROUGH MUCH OF
THE DAY SUNDAY. STRONG NORTH SURFACE WINDS WILL LIKELY ALSO CAUSE
SOME BLOWING SNOW LATER TONIGHT AND AT LEAST THROUGH EARLY SUNDAY
AFTERNOON.
HEADLINES WILL CONTINUE UNTIL 6 PM SUNDAY IN NEBRASKA AND UNTIL 9 PM
SUNDAY IN SOUTHWEST IOWA. IT IS POSSIBLE THESE MAY BE CANCELLED
EARLIER THAN THAT...BUT THAT IS WHAT WE WILL GO WITH FOR NOW.
SNOW AMOUNTS WILL DECREASE THROUGH THE DAY AS DRIER AIR MOVES IN
FROM THE WEST AND LIFT PULLS OUT OF THE REGION. HIGH PRESSURE AT
THE SURFACE BUILDS IN FOR SUNDAY NIGHT. WINDS WILL DECREASE AND
WITH CLEARING SKIES HAVE LOWS FALLING OR AROUND ZERO...OR EVEN
BELOW ZERO IN OUR NORTHERN COUNTIES. WARM AIR ADVECTION AND SOUTH
WINDS SHOULD INCREASE MONDAY. KEPT A SMALL CHANCE OF SNOW NORTH
AND NORTHEAST OF OMAHA...BUT NOT A BIG DEAL. A SLIGHTLY BETTER
CHANCE OF SNOW ARRIVES FOR TUESDAY. 12Z GFS SEEMED A BIT TOO HIGH
ON QPF TUESDAY...BUT WILL SEE HOW THINGS TREND NEXT FEW MODEL
RUNS.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 325 PM CST SAT JAN 31 2015
LOOK FOR MODERATING TEMPERATURES THIS PERIOD. FAST WEST/NORTHWEST
MID LEVEL FLOW WILL OCCUR EARLY...WITH A RIDGE DEVELOPING OVER THE
WESTERN US. THIS RIDGE SHOULD BUILD EAST THROUGH THE WEEK. HIGHS
WILL BE 20S WEDNESDAY AND THURSDAY RISING TO ABOVE NORMAL FOR
FRIDAY AND SATURDAY. THERE IS SOME CHANCE OF LIGHT SNOW WEDNESDAY
OTHERWISE IT SHOULD BE MAINLY DRY.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 518 PM CST SAT JAN 31 2015
WINTER EVENT WILL IMPACT THE TAF SITES THROUGH MOST OF THE PERIOD.
IFR AND OCCASIONALLY LIFR CONDITIONS WITH SNOW AT ALL TAF SITES
WITH VISIBILITIES RANGING FROM 1/2 TO 1 1/2 MILES MOSTLY. WINDS
REMAIN LIGHT FROM THE EAST OR SOUTHEAST INITIALLY. WINDS WILL
CONTINUE TO BACK BECOMING NORTHEAST...THEN NORTH AND SUBSTANTIALLY
INCREASING BY 11-13Z TO 22 TO 35 KNOTS. AT THAT TIME...SNOW AND
BLOWING SNOW WILL CONTINUE TO REDUCE VISIBILITY THROUGH MUCH OF
THE DAY SUNDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 6 PM CST SUNDAY FOR NEZ011-016-017-
030-031-090>093.
WINTER STORM WARNING UNTIL 6 PM CST SUNDAY FOR NEZ012-015-018-
032>034-042>045-050>053-065>068-078-088-089.
IA...WINTER STORM WARNING UNTIL 9 PM CST SUNDAY FOR IAZ043-055-056-
069-080-091.
WINTER STORM WARNING UNTIL 6 PM CST SUNDAY FOR IAZ079-090.
&&
$$
UPDATE...DEWALD
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1242 AM CST SUN FEB 1 2015
.UPDATE...
ISSUED AT 1241 AM CST SUN FEB 1 2015
QUICK UPDATE TO CAPTURE LATEST TRENDS.
SNOW CONTINUES TO DIMINISH ACROSS CENTRAL AND SOUTHERN NORTH
DAKOTA. ADDITIONAL ACCUMULATION OF ONE INCH OR LESS IS POSSIBLE
SOUTH OF I-94. SNOW SHOULD BE COMPLETELY OUT OF THE AREA BY
SUNRISE. WIND CHILL TEMPERATURES CONTINUE TO DROP INTO THE TEENS
AND 20S BELOW ZERO. ONLY OTHER MINOR CHANGE WAS TO SKY COVER.
CLEARED OUT THE CLOUDS FROM NORTH TO SOUTH A LITTLE SOONER THAN
PREVIOUSLY FORECAST.
UPDATE ISSUED AT 944 PM CST SAT JAN 31 2015
NO SIGNIFICANT CHANGES REQUIRED WITH THIS UPDATE OTHER THAN TO
BLEND TO OBSERVED TRENDS THROUGH 03 UTC AS THE FOCUS FOR SNOWFALL
WILL CONTINUE TO SHIFT INTO FAR SOUTH CENTRAL NORTH DAKOTA THROUGH
THE NIGHT. FRONTOGENESIS AND DENDRITIC OMEGA ARE DECREASING AS
EXPECTED...MARKING A SLOW DECLINE IN SNOWFALL INTENSITY.
UPDATE ISSUED AT 547 PM CST SAT JAN 31 2015
RADAR TRENDS THROUGH 2330 UTC ARE ALIGNED WELL WITH THE 20
THROUGH 22 UTC HRRR ITERATIONS...AND WILL WEIGH HEAVILY UPON THEIR
SOLUTIONS FOR THE REMAINDER OF THE NIGHT. EXPECT A BAND OF
MODERATE TO AT TIMES HEAVY SNOW TO CONTINUE TO DEVELOP FROM CENTER
THROUGH BISMARCK...NEW SALEM...FLASHER...CARSON AND MOTT THROUGH
03 UTC IN ASSOCIATION WITH STRENGTHENING 850-700 MB FRONTOGENESIS.
WHILE SNOW WILL CONTINUE THEREAFTER...PEAK INTENSITIES WILL BEGIN
TO SLOWLY DECREASE.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 245 PM CST SAT JAN 31 2015
.SHORT TERM...TONIGHT AND SUNDAY...
MAIN ISSUED THIS FORECAST PERIOD WILL BE SNOW POTENTIAL THIS
AFTERNOON AND EVENING. SNOW IS STILL FORECAST TO REMAIN BELOW
ADVISORY CRITERIA WITH FAIRLY WIDESPREAD SNOW AMOUNTS OF 3 INCHES
ACROSS WEST CENTRAL ND THIS AFTERNOON WITH 2 TO 3 INCHES SPREADING
INTO THE SOUTH CENTRAL TONIGHT. AN ISOLATED 4 INCH AMOUNT IS
POSSIBLE BUT NOT WIDESPREAD. THEN WIND CHILLS BECOME A CONCERN
ACROSS THE NORTH CENTRAL THROUGH THE NORTHERN JAMES RIVER VALLEY
TONIGHT INTO SUNDAY MORNING. LATEST RADAR TRENDS SHOW THE SNOW THIS
AFTERNOON IS CONCENTRATED ACROSS THE WEST CENTRAL WHERE UP TO 3
INCHES MAY FALL BY EARLY EVENING. THEN THIS EVENING THEN SNOW WILL
BE FOCUSED ALONG AN H300 JET REGION WHICH EXTENDS NORTHEAST TO
SOUTHWEST ACROSS WESTERN NORTH DAKOTA. THE LATEST HRRR RUNS FOLLOW
THE JET DYNAMICS AND FORM A SNOW BAND THAT EXTENDS FROM SOUTHWEST
NORTH DAKOTA INTO THE SOUTH CENTRAL BETWEEN 00Z-06Z. BELIEVE THERE
WILL ANOTHER 3 INCH BAND OF SNOW FROM BOWMAN NORTHEAST TO BISMARCK.
THE MOST RAPIDLY CHANGING WEATHER WILL BE FOUND SOUTH CENTRAL WHERE
THE PARTLY SUNNY SKIES THIS AFTERNOON WILL QUICKLY CHANGE TO SNOW.
BUFKIT SOUNDINGS FROM DICKINSON TO BISMARCK THIS EVENING SHOW A
FAIRLY DEEP DENDRITIC GROWTH ZONE WITH SUPER SATURATION WITH RESPECT
TO ICE. THUS THERE WILL BE GOOD SNOW POTENTIAL FROM THE LIMITED QPF
THAT HAS BEEN CONSISTENTLY FORECAST FOR THIS SYSTEM.
THIS EVENING...WILL ISSUE A WIND CHILL ADVISORY FOR WIND CHILLS 25
TO 30 BELOW EXTENDING FROM BOTTINEAU COUNTY SOUTHEAST THROUGH
STUTSMAN COUNTY. TOWNS INCLUDED IN THIS AREA INCLUDE
BOTTINEAU...RUGBY... HARVEY AND JAMESTOWN.
BY SUNDAY MORNING THE SNOW WILL END. SHOULD SEE CONSIDERABLE
SUNSHINE BOT COLD TEMPERATURES SUNDAY
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 245 PM CST SAT JAN 31 2015
THE PATTERN REMAINS UNSETTLED FOR THE EARLY AND LATTER PORTIONS OF
THE LONG TERM PERIOD. SHORTWAVE TROUGHS CONTINUE TO CIRCULATE AROUND
THE HUDSON BAY LOW AND INTO NORTH DAKOTA. ALTHOUGH THERE APPEARS TO
BE A BREAK WEDNESDAY INTO EARLY FRIDAY...BOTH THE GFS AND ECMWF ARE
HINTING AT ANOTHER SYSTEM FRIDAY NIGHT THROUGH SATURDAY.
SUNDAY NIGHT AND MONDAY...NOT A LOT OF CHANGE FROM PREVIOUS RUNS AND
THOUGHTS AS THIS WILL BE A BRIEF/MINOR WARM AIR ADVECTION
PRECIPITATION EVENT MONDAY. SOUTHWEST WINDS SUNDAY NIGHT WILL QUICKLY
SHIFT TO THE NORTHWEST DURING THE MORNING IN THE WEST AND AFTERNOON
IN THE CENTRAL AS COLD AIR ADVECTION AGAIN TAKES CONTROL. PER
NAM/GFS BUFKIT SOUNDINGS...HAVE TEMPERED HIGHS IN THE SOUTHWEST AS
COLD AIR ADVECTION TAKES OVER BY MID TO LATE MORNING AND BASICALLY
PUTS A CAP ON RISING TEMPERATURES. SNOWFALL POTENTIAL REMAINS LIGHT
WITH AROUND A HALF INCH ALONG AND WEST OF THE MISSOURI RIVER.
FOR TUESDAY...IT APPEARS THE STRONGER BAROCLINIC ZONE ASSOCIATED
WITH AN ARCTIC INTRUSION REMAINS IN SOUTH CENTRAL MONTANA AND
WESTERN SOUTH DAKOTA. THE GFS HAS SHIFTED THE MAIN SNOW AXIS ACROSS
THE FAR SOUTHWEST. THE NAM/ECMWF ALSO INDICATE A WEAKER SCENARIO BUT
HAVE THIS AREA FARTHER EAST AS WELL. QPF TODAY VERSUS THE LAST FEW
RUNS HAVE LOWERED QUITE A BIT. SNOWFALL ACCUMULATIONS ARE NOW MORE
LIKELY TO RANGE FROM 1 TO 1.5 INCHES ACROSS WESTERN AND SOUTH
CENTRAL NORTH DAKOTA.
WEDNESDAY THROUGH SATURDAY...MAINLY DRY CONDITIONS CAN BE EXPECTED AS
NORTHWEST FLOW CONTINUES WEDNESDAY WITH ARCTIC AIR AND SURFACE HIGH
PRESSURE DOMINATING. HIGHS WILL RANGE FROM AROUND ZERO IN THE TURTLE
MOUNTAINS TO 20 DEGREES ABOVE ZERO IN THE SOUTHWEST. WARM AIR
ADVECTION ONCE AGAIN COMMENCES THURSDAY AND FRIDAY. AN ALBERTA
CLIPPER WITH A FAIRLY TIGHT BAROCLINIC ZONE IS FORECAST TO DEVELOP
ACROSS CENTRAL AND NORTHERN NORTH DAKOTA FRIDAY THROUGH SATURDAY.
THE ECMWF IS MUCH COLDER AS THE BAROCLINIC ZONE SAGS FURTHER SOUTH.
BOTH MODELS DEPICT DECENT PRECIPITATION DEVELOPING DURING THIS
PERIOD AND SNOW WOULD BE THE LIKELY CANDIDATE IN THE NORTH. THERE IS
A POTENTIAL FOR A WINTRY MIX IN/AROUND THE WARMER SIDE OF THE
BAROCLINIC ZONE. WILL NEED TO MONITOR THIS IN THE COMING DAYS. HIGH
TEMPERATURES FRIDAY/SATURDAY WILL DEPEND ON WHERE THE BAROCLINIC
ZONE SETS UP ACROSS SOUTHWEST/NORTHERN NORTH DAKOTA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1241 AM CST SUN FEB 1 2015
IFR CONDITIONS IN SNOW WILL CONTINUE AT KDIK AND KBIS THROUGH
ABOUT 07-09 UTC. OTHERWISE VFR CONDITIONS WILL PREVAIL AT ALL TAF
SITES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR NDZ004-005-
012-013-022-023-025-036-037.
&&
$$
UPDATE...AJ
SHORT TERM...WAA
LONG TERM...KS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
142 AM EST SUN FEB 1 2015
.SYNOPSIS...
LOW PRESSURE TRAVELING UP THE OHIO VALLEY WILL BRING WIDESPREAD
SNOW AND RAIN TONIGHT INTO MONDAY. MUCH COLDER AIR WILL ARRIVE MONDAY
NIGHT WITH HIGH PRESSURE MOVING IN FROM THE WEST. SNOW AND RAIN
WILL BE POSSIBLE WEDNESDAY WHEN A DISTURBANCE IS FORECAST TO CROSS
THE GREAT LAKES.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
THE FIRST CONCERN FOR THE NEAR TERM OF THE FORECAST WAS TO ADD
SOME MORE SLEET. THIS IS BASED PARTLY ON SEVERAL REPORTS IN
SOUTHEASTERN INDIANA...BUT ALSO BASED ON THE WAY CONDITIONS HAVE
EVOLVED TONIGHT AS EVIDENCED BY OBSERVATIONS. DEWPOINT DEPRESSIONS
ARE STILL RATHER HIGH...WITH WET BULB TEMPERATURES BELOW ZERO. THE
KILN SOUNDING INDICATED QUITE A BIT OF DRY AIR BELOW 900MB...BUT
ALSO INDICATED THAT THE WARM LAYER IN THE LOWEST 2KM WAS SLIGHTLY
WARMER THAN THE CURRENT FORECAST HAD SUGGESTED WAS GOING TO
HAPPEN. WITH A SLIGHTLY WARMER STARTING POINT...THE ZONE OF MIXED
PRECIP AND ICE ACCUMULATIONS HAS BEEN SHIFTED SLIGHTLY NORTHWARD.
HOWEVER...THESE ACCUMULATIONS SHOULD STILL REMAIN FAIRLY
LIGHT. THE SOUTHERN TIER OF THE WINTER WEATHER ADVISORY WILL COVER
THE THREAT NICELY...AND IN FACT...THE FAR SOUTHERN COUNTIES IN THE
ADVISORY MAY NOT GET COLD ENOUGH TO SUPPORT MUCH OF A THREAT FOR
ANY GLAZE ACCUMULATION (PERHAPS JUST SOME SLEET MIXING IN NEAR THE
ONSET OF PRECIPITATION).
BASED ON A FULL ANALYSIS OF 18Z MODEL RUNS...RECENT RAP/HRRR
RUNS...AND THE 00Z NAM...ANOTHER SLIGHT ADJUSTMENT WAS MADE TO THE
OVERALL FORECAST ARRANGEMENT FOR SUNDAY. THERE ARE NO SIGNS AT ALL
OF A REVERSAL OF THE GRADUAL NORTHWARD (WARMER) TREND...AND THE
02Z RAP / 00Z NAM ARE PERHAPS AS FAR NORTH WITH THE WARM AIR AS
ANY MODEL HAS BEEN THROUGH THE FORECAST OF THIS EVENT. IT IS STILL
VERY CLEAR THAT ANY LOCATION THAT REMAINS PURELY SNOW WILL RECEIVE
A VERY LARGE AMOUNT (AROUND A FOOT)...BUT THE TRANSITION ZONE
SEEMS TO BE CREEPING NORTHWARD WITH EACH NEW MODEL CYCLE.
THUS...WHILE SNOW TOTALS IN THE FAR NORTHERN CWA (MERCER THROUGH
HARDIN) REMAIN AS HIGH AS BEFORE (UP TO 12 INCHES)...A MODEST
DOWNWARD ADJUSTMENT WAS MADE FURTHER SOUTH. THE NEW WSW PRODUCT
ACCOUNTS FOR THIS CHANGE WITH SOME REFINED AND SLIGHTLY LOWER
NUMBERS FOR SOME OF THE COUNTY SEGMENTS. HOWEVER...IT WOULD BE
PREFERRED TO SEE THE ENTIRE 00Z MODEL SUITE BEFORE MAKING A MORE
SUBSTANTIAL CHANGE (AS WOULD BE SUGGESTED BY THE LATEST MODELS).
PREVIOUS DISCUSSION >
SURFACE LOW PRESSURE WILL DEVELOP OVER THE GREAT PLAINS TONIGHT IN
RESPONSE TO A DIGGING 500 MB TROUGH OVER THE ROCKIES. WHILE JET
STREAM ENERGY INCREASES AS IT ROUNDS THE BASE OF THE UPPER
TROUGH...THE SURFACE LOW WILL DEEPEN...AND THE PRESSURE GRADIENT
WILL TIGHTEN...INCREASING MOISTURE ADVECTION TOWARD THE OHIO
VALLEY.
DURING THIS PROCESS...A BAND OF ISENTROPIC LIFT WILL SET UP OVER
THE ILN AREA WELL AHEAD OF THE SURFACE LOW TO THE WEST. LATEST
MODELS SHOW THE BAND AFFECTING LOCATIONS MAINLY NORTH OF
CINCINNATI. PRECIP WILL START AROUND MIDNIGHT...WITH TYPE VARYING
WITH RESPECT TO ATMOSPHERIC TEMPERATURE PROFILES. EXPECT DEFINITE SNOW
FOR THE NORTH HALF OF THE FA INCLUDING DAYTON...COLUMBUS AND
WAPAKONETA. FOR LOCATIONS ROUGHLY NEAR WILMINGTON...WARMER AIR
ALOFT SHOULD ALLOW A WINTRY MIX. FARTHER SOUTH FROM CINCINNATI TO
PORTSMOUTH AND ACROSS NORTHERN KENTUCKY...THERE WILL BE A CHANCE
FOR A LIGHT WINTRY MIX OF FZRA AND RA.
DUE TO THE SIGNIFICANT NATURE OF SNOW ACCUMULATIONS BASED ON
QPF AND MODEL SOUNDINGS...WENT WITH A WINTER STORM WARNING FOR
SNOW NORTH OF DAY AND CMH. FARTHER SOUTH WENT WITH A WINTER
WEATHER ADVISORIES FOR LIGHTER SNOW AND ICE ACCUMULATIONS. SEE
CLEWSWILN FOR FURTHER DETAILS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
SURFACE LOW WILL PROGRESS UP THE OHIO VALLEY TO SOUTHERN INDIANA ON
SUNDAY. WHILE SNOW PERSISTS NORTH OF DAYTON...CONTINUED MOISTURE
ADVECTION ALONG THE WARM CONVEYOR BELT AHEAD OF THE LOW WILL ALLOW
PRECIP TO OVERSPREAD THE AREA BY SUNDAY EVENING. WITH MODELS
PRESENTING A WARMER SOLUTION...RAIN IS THE ANTICIPATED PRECIP TYPE
SOUTH OF I-70...WITH SNOW NORTH. A BAND OF FRONTOGENETIC FORCING
WILL ENHANCE PRECIP ESPECIALLY ACROSS THE NORTH WHERE SIGNIFICANT
SNOW WILL ACCUMULATE.
THE SURFACE LOW WILL BE MOVING FROM EASTERN OHIO TO PENNSYLVANIA
BY MONDAY MORNING. PRECIP WILL TRANSITION TO ALL SNOW AREA WIDE
BEFORE DIMINISHING IN COLD ADVECTION BEHIND THE DEPARTING LOW.
SNOW IN THE NORTH WILL BE ENHANCED BY STRONG DEFORMATION IN THE NW
QUADRANT OF THE LOW. TOTAL SNOW AMOUNTS WILL VARY GREATLY...WITH
OVER 10 INCHES POSSIBLE OVER WEST CENTRAL OHIO...A FEW INCHES NEAR
DAYTON AND COLUMBUS...AND UNDER AN INCH AT CINCINNATI...PORTSMOUTH
AND NORTHERN KENTUCKY.
COLD TEMPERATURES AND WIND CHILLS ARE IN STORE FOR MONDAY AND
MONDAY NIGHT. HIGHS IN THE TEENS AN 20S MONDAY WILL BE FOLLOWED BY
LOWS RANGING FROM THE NEGATIVE SINGLE DIGITS NORTH TO THE MID
TEENS SOUTH MONDAY NIGHT. THE COLD TEMPS WILL COMBINE WITH BRISK
WINDS TO PRODUCE WIND CHILLS BELOW MINUS 10 OVER THE NORTH HALF OF
THE FA. WILL MENTION WIND CHILLS IN HWO FOR NOW...AND A WIND CHILL
ADVISORY MAY EVENTUALLY BE ISSUED ACROSS THE NORTH.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
NORTHWEST MID/UPPER LEVEL FLOW WITH THE CENTER OF SPRAWLING SURFACE
HIGH PRESSURE SLIDING OFF TO THE EAST COAST BY TUESDAY EVENING. THIS
HIGH WILL PROVIDE COLD AND DRY WEATHER CONDITIONS. AFTER A COLD
START TO THE DAY...TEMPERATURES WILL WARM TO HIGHS 5 TO 10 DEGREES
BELOW NORMAL. TUESDAYS HIGHS TO RANGE FROM THE MID 20S NE TO THE
UPPER 30S SW.
FLOW BACKS WESTERLY A HEAD OF DIGGING TROF OVER THE GREAT LAKES...
WITH A QUICK MORNING SYSTEM MOVING THRU THE REGION TUESDAY
NIGHT/WED. WILL HAVE CHANCE POPS FOR THIS PERIOD WITH THE BEST
CHANCE ACRS THE NORTH. PCPN WILL LKLY MIX WITH AND CHANGE TO RAIN
IN THE SOUTH PRIOR TO COLD FRONTAL PASSAGE WED AFTN. LOWS TUESDAY
NIGHT TO RANGE FROM THE LOWER 20S NE TO THE UPPER 20S SW. HIGHS ON
WED FROM THE LOWER 30S NORTH TO THE LOWER/MID 40S FAR SOUTH.
REINFORCING SHOT OF COLD AIR WITH HIGH PRESSURE OF CANADIAN ORIGIN
TO BUILD SE BECOMING CENTERED OVER OHIO THURSDAY. COLD AND DRY
WEATHER ON TAP WITH WED NIGHT/S LOWS FROM THE SINGLE DIGITS ACRS THE
NORTHWEST WHERE SNOW PACK WILL EXIST TO NEAR 20 SE. HIGHS ON THURSDAY
TO BE AROUND 15 DEGREES BELOW NORMAL...RANGING FROM THE UPPER TEENS
NW TO THE UPPER 20S SE.
THIS SFC HIGH BUILDS SLOWLY EAST TO THE EAST COAST BY THE END OF THE
WEEK. COLD TEMPERATURES TO CONTINUE WITH LOWS THURSDAY NIGHT FROM
THE SINGLE DIGITS BELOW ZERO NW TO NEAR 10 SE.
AS THE HIGH MOVES OFF TO THE EAST A RETURN FLOW DEVELOPS WITH SOME
SOME MODERATION TO TEMPERATURES INTO THE WEEKEND. HIGHS ON FRIDAY
FROM NEAR 20 NORTH TO THE LOWER 30S FAR SOUTH AND WARMING ON
SATURDAY FROM THE UPPER 20S NORTH TO AROUND 40 SOUTH. MODEL SOLN
SPREAD LARGE NEXT SATURDAY REGARDING TIMING AND PLACEMENT OF NEXT
SYSTEM. HAVE KEPT FCST DRY THRU SAT AFTN ATTM MORE LIKE THE GFS SOLN
BUT THIS MAY CHANGE WITH LATER UPDATES.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
A BAND OF SNOW AND MIXED PRECIPITATION IS LIFTING NORTH THROUGH
THE REGION AND WILL CONTINUE TO AFFECT NORTHERN TAF SITES KDAY AND
KCMH/LCK UNTIL ABOUT 9Z AT KDAY AND 12Z FOR KCMH/LCK. A DRY PUNCH
WILL PULL IN WARM AIR AND PRECIP SHOULD SHUT OFF FOR A MAJORITY
OF THE DAY TODAY AT MOST SITES...WITH KCMH/LCK HANGING ON TO THE
LOWER CIGS IN SHOWERS THROUGH EARLY MORNING.
IN THE AFTERNOON...TOWARDS 20Z...THE PREVAILING RAIN WILL RAPIDLY
OVERSPREAD THE REGION FROM THE WEST. THE LOW WILL TRACK NORTH OF
KCVG AFTER 0Z AND UNTIL THIS HAPPENS...THE WARM AIR WILL AFFECT
ALL TAF SITES. TEMPERATURES WILL RAPIDLY DECREASE AS THE LOW
CROSSES AND WEST WINDS GUSTING TO 25KT WILL ACCOMPANY A RAPID
CHANGEOVER TO SNOW.
WITH THE EXCEPTION OF THE RESPITE IN PRECIP DURING DAYLIGHT HOURS
TODAY...CIGS WILL BE MVFR AND COULD DROP TO IFR IN HEAVIER RAIN
AND/OR SNOW SHOWERS.
OUTLOOK...MVFR CEILINGS ARE EXPECTED TO CONTINUE INTO MONDAY.
MVFR CEILINGS ARE POSSIBLE WEDNESDAY THROUGH WEDNESDAY NIGHT.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
OHZ063>065-070>074-077>080-082.
WINTER STORM WARNING UNTIL 7 AM EST MONDAY FOR OHZ026-034-035-
042>046-051-052.
WINTER WEATHER ADVISORY UNTIL 7 AM EST MONDAY FOR OHZ053>056-
060>062.
KY...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
KYZ089>093.
IN...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR INZ058-
059-066-073>075-080.
WINTER WEATHER ADVISORY UNTIL 7 AM EST MONDAY FOR INZ050.
&&
$$
SYNOPSIS...CONIGLIO
NEAR TERM...CONIGLIO/HATZOS
SHORT TERM...CONIGLIO
LONG TERM...AR
AVIATION...FRANKS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
424 AM EST SUN FEB 1 2015
.SYNOPSIS...
LOW PRESSURE WILL CROSS THE CENTRAL MISSISSIPPI RIVER VALLEY
TODAY AND MOVE INTO THE OHIO VALLEY TONIGHT...AND CROSS THE STATE
ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION
ACROSS THE AREA THIS AFTERNOON INTO MONDAY. A PERIOD OF FREEZING
RAIN IS LIKELY ACROSS THE SOUTH AND CENTRAL SECTIONS TONIGHT.
ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY AFTERNOON INTO
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LIGHT PRECIPITATION DEVELOPING WELL OUT AHEAD OF SFC LOW OVER
EASTERN KANSAS THIS MORNING...ALONG A COLD FRONTAL BOUNDARY
DROPPING SOUTHWARD ACROSS THE EASTERN GREAT LAKES AND OHIO VALLEY.
THE AFOREMENTIONED LOW PRESSURE CENTER WILL TRACK ALONG THIS
BOUNDARY THIS AFTERNOON AND TONIGHT...AND ACROSS THE SOUTHERN TIER
OF PENNSYLVANIA BY MONDAY MORNING.
ALL HEADLINES RETAINED FOR THIS FORECAST CYCLE. MAIN CONCERNS ARE
THAT POPS WERE TOO HIGH TO BEGIN THE STORM THIS AFTERNOON...WHERE
ONLY VERY LIGHT AMOUNTS OF QPF AND SNOW ARE EXPECTED. IN
FACT...HI RES HRRR AND HRW-ARW SHOW A FRACTURED MOTHEATEN PRECIP
SHIELD AT BEST REACHING ACROSS THE ALLEGHENIES LATE THIS MORNING
AND AFTERNOON AND LARGELY DISSIPATING DURING THE MID TO LATE
AFTERNOON HOURS. THINK THERE WILL BE A SIZABLE LULL IN
PRECIPITATION FOR MANY AREAS THIS AFTERNOON BEFORE THE MAIN EVENT
APPROACHES THIS EVENING AND LATER TONIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
LOW PRESSURE MOVES UP THE OHIO RIVER TONIGHT. BY MONDAY MORNING
IT SHOULD BE OVER KPIT...AND ROLL OVER THE SOUTHERN HALF OF THE
LOCAL AREA. MAIN QPF FALLS IN THE 03Z TO 09Z TIMEFRAME FOR MANY...
AND THIS SIX HOUR PERIOD WILL BE CRITICAL FOR SNOW ACCUMS OVER THE
CENTRAL MOUNTAINS...JUST NORTH OF THE CHANGEOVER ZONE. FASTER/
GREATER MIXING WILL DECREASE SNOW AMOUNTS SUBSTANTIALLY. FOR NOW
HAVE NUDGED THE MIXING ZONE NORTH AND DECREASED SNOW AMOUNTS SOUTH
OF INTERSTATE 80 INTO THE 4-6" RANGE. AS A RESULT...GREATER FZRA
POTENTIAL EXISTS WITH THIS SOLUTION THAN PREVIOUS THINKING.
WHILE THE FARTHER NORTH/WARMER SOLUTION WILL CUT DOWN THE SNOW
AMOUNTS IN THE CENTRAL ZONES...WARNING CRITERIA SNOWFALL IS
EXPECTED NORTH OF INTERSTATE 80. ADVY AND SUB ADVISORY SNOW
AMOUTNS ARE EXPECTED ACROSS THE SOUTHERN THIRD OF CENTRAL PA...
BUT THE CHANCE FOR ICING IS ENOUGH TO WARRANT AT LEAST AN ADVY
FOR THEM.
SFC LOW RAPIDLY TRACKS EAST OF THE AREA BY MIDDAY MONDAY...WITH
COLDER AIR POURING BACK INTO THE COMMONWEALTH ON THE BACKSIDE OF
THE LOW. EXPECT LITTLE IF ANY ADDITIONAL SNOW ACCUMULATION BY MON
AFTERNOON ACROSS THE NORTH. PRECIP WILL HAVE SHUT OFF ACROSS
CENTRAL AND SOUTHERN AREAS BY MIDDAY. SHARPLY COLDER AIR IS POISED
TO OVERSPREAD CENTRAL PA AGAIN ON MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY
MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD
NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW
ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY
DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP
WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND
LAUREL HIGHLANDS LIKELY NEEDING A WIND CHILL ADVISORY /-15F/ MON
NIGHT INTO EARLY TUE. THIS COULD ADD TO STORM-RELATED
IMPACTS...INCLUDING POTENTIAL FOR PATCHY BLACK ICE.
HIGH PRESSURE WILL BRING COLD BUT GENERALLY QUIET WEATHER INTO
MIDWEEK. A WEAK SYSTEM MOVES THROUGH WED THAT MAY BRING LIGHT
ACCUMS TO THE NW HALF /BEFORE THE SYSTEM DEEPENS MORE RAPIDLY OVER
NEW ENGLAND/...WHICH WILL BE FOLLOWED BY A SHOT OF MORE ARCTIC AIR
AS COLD HIGH PRESSURE BUILDS IN FOR THU INTO FRI - INCLUDING A
RETURN OF BELOW ZERO WIND CHILLS.
TEMPS MODERATE A BIT...BUT REMAIN BELOW NORMAL...ON SAT. ANOTHER
LOW PRESSURE AREA MAY IMPACT THE REGION ON SUNDAY...BUT AT THIS
TIME IT LOOKS TO BE ON THE WEAKER SIDE.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
THE RIDGE CONTINUES TO WEAKEN AS THE SHALLOW ARTIC AIR HAS MAINLY
DISSIPATED AS ITS MOVED EASTWARD. THIS HAS DELAYED THE ONSET OF
MVFR CIGS /AND ANY GRADUALLY DETERIORATING VSBYS TO IFR. THE ONSET
OF CONDITIONS HAS BEEN PUSHED BACK. THE LOWERING CONDITIONS WILL
OCCUR FROM WEST TO EAST BETWEEN 11-18Z AS DEEPENING MOISTURE /AND
THE ONSET OF LIGHT SNOW/ STREAKS EASTWARD ALONG AND AHEAD OF A
SLOWLY SWD SAGGING COLD FRONT.
WIDESPREAD IFR TO LIFR CONDITIONS ARE IN STORE FOR LATE SUNDAY
INTO EARLY MON AS HEAVIER SNOW IMPACTS THE NORTHERN HALF OF THE
STATE. THE SOUTHERN HALF WILL SEE A WINTRY MIX WORK INTO THE
SOUTHERN TAF SITES...FROM JST AND AOO...TO KMDT- KLNS AREA WITH
POTENTIAL FOR ICING. THIS IS DUE TO WARM AIR ADVECTION INTO THE
MID LEVELS...AND COLD TEMPERATURES AT THE SURFACE. LLWS POSS
SUNDAY NIGHT ACROSS THE S/SE AS LOW LEVEL JET ROTATES THROUGH.
OUTLOOK...
SUN...WIDESPREAD IFR-MVFR CIGS AND IFR VSBYS DEVELOPING DURING THE
MORNING-EARLY AFTERNOON HOURS. LLWS POSS SUN NIGHT SE.
MON...REDUCED CONDS EARLY...GRADUALLY IMPROVING AS THE STORM
MOVES AWAY FROM THE AREA. LLWS POSS MON AFT/NIGHT.
TUE...NO SIG WX.
WED...MVFR IN SHSN NW...VFR SE.
THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM 9 AM THIS MORNING TO 1 PM EST MONDAY
FOR PAZ004>006-010>012-017>019-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 8 AM EST
MONDAY FOR PAZ033>036-064>066.
WINTER STORM WARNING FROM 9 AM THIS MORNING TO 8 AM EST MONDAY
FOR PAZ024>028-056-057-059-063.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...RXR
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1115 PM CST SAT JAN 31 2015
.AVIATION...
/06Z TAFS/
Most West Central TX forecast terminals are reporting MVFR
ceilings as of 05z, but conditions should deteriorate overnight
with most areas dropping into IFR (with ceilings under 1000 ft).
Scattered showers will affect KSJT, KABI, and KSOA early this
morning, but confidence is too low to mention elsewhere.
Otherwise, expect patchy fog/drizzle to restrict visibilities at
times. Winds will veer to the southwest late tonight, shifting to
the north as a cold front moves across the area during the late
morning and early afternoon hours. Winds will be gusty through
around 00z, eventually subsiding after sunset. Ceilings will
rapidly improve behind this front with VFR conditions expected
areawide by mid- afternoon.
Johnson
&&
.PREV DISCUSSION... /ISSUED 917 PM CST SAT JAN 31 2015/
UPDATE...
Updated the grids and zones to go with chance POPS across the
entire area tonight. Also, a few thunderstorms are possible
across the Northern Edwards Plateau.
PREV DISCUSSION... /ISSUED 638 PM CST Sat Jan 31 2015/
AVIATION...
/00Z TAFS/
Ceilings remain below 1500 ft across most of West Central TX, with
many forecast terminals experiencing IFR (or worse) conditions.
The primary rain shield has moved east of the forecast area.
However, isentropic ascent will ramp up overnight, resulting in
lowering ceilings and potential light precipitation, mainly in the
form of drizzle. This will knock cloud bases down to generally
700 ft or lower and should cause prevailing visibilities to drop
to 5 miles or less. Some locations may experience more significant
reductions in visibility. Expect poor flight conditions overnight
but winds will veer to the southwest overnight ahead of a cold
front. This front will move through the Big Country mid/late
morning, bringing drier air into the area and eroding the low
clouds from north to south throughout the day. Gusty north winds
will prevail in the wake of this front.
PREV DISCUSSION... /ISSUED 351 PM CST SAT JAN 31 2015/
SHORT TERM...
(Tonight and Sunday )
Light rain was moving north of I-20, and east of an Abilene...
Brady...Mason line at 3 PM. An upper low was west of El Paso,
moving slowly southeast.
Rain was pushing east and ending of West Central, faster than the
models indicated. Indeed at the current pace, nearly all the
present rain at 3 PM will be east or north of West Central Texas
by 6 PM. Kept a chance of showers going overnight, however, with
the El Paso low sending weak disturbances eastward. Additional
rainfall amounts will be light...ranging from a trace to a few
hundredths inch. The NAM and EC models bring isolated to scattered
light showers over West Central Texas tonight. The GFS model`s
convective algorithm is dry. The short range HRRR model brings in
scattered showers, mainly over Crockett county, the Concho Valley
and areas southward. Timing was between 9 PM and 4 AM. This may
actually be the best model as it seems to latched on an area of
lift in the water vapor loop south of El Paso.
A cold front will move through West Central Texas Sunday bringing
gusty north winds by noon. This clear low level moisture and
clouds. Sunshine in the afternoon should allow afternoon highs to
be a 2-4 degrees warmer than today`s, despite cold air advection.
LONG TERM...
(Sunday night through next Saturday)
Warmer weather will make a return to West Central Texas for the
first half of the week. An area of high pressure centered over the
region on Monday, will slide off to our east by mid-week. A
thermal ridge at 850 mb will expand east over the area, allowing
high temperatures to climb from the mid 50s on Monday, to the mid
60s by Wednesday. A weak cold front approaching the area from the
north Wednesday night, will wash out near Interstate 10 during the
day Thursday, bringing cooler/drier air to the region. However,
this will be short-lived, as a lee trough develops to our west on
Friday. With a return flow developing, warmer temperatures and
increasing moisture are expected.
Precipitation chances may also increase for the southern half of
the forecast area. An upper-level disturbance currently located
over Baja California, is expected to pass by to our southeast
Tuesday night/Wednesday morning. This system may bring a chance of
rain to the region, mainly south of a line from San Angelo to
Brownwood. This afternoon`s numerical models have once again
shifted the track of the disturbance farther south and east,
reducing forecast confidence. However, the models have been flip-
flopping on the track for the last few model runs, and considering
the system is still largely in a data-void region, this will
likely continue through the next 48 hours. By then, the system
will enter an improving observational/upper-air network, which may
result in improved model continuity. Given the concerns mentioned
above, only minimal changes were made to the rainfall forecast for
the middle of the week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 49 51 24 51 36 / 40 10 5 5 5
San Angelo 51 60 27 54 36 / 30 10 5 5 5
Junction 52 64 30 55 34 / 40 20 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
25
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
323 AM CST SUN FEB 1 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 323 AM CST SUN FEB 1 2015
CHALLENGES THIS MORNING INCLUDE SNOW AMOUNTS AND ASSOCIATED
HEADLINES. 01.00Z MODELS ARE IN GOOD OVERALL AGREEMENT AND WILL
USE A BLENDED SOLUTION.
CALLS TO LAW ENFORCEMENT EARLY THIS MORNING REVEALED 4 TO 5 INCHES
IN OSAGE AND 3 TO 4 INCHES IN DECORAH. FURTHER NORTH ALONG THE
I-90 CORRIDOR FROM ROCHESTER TO LA CROSSE...1 TO 2 INCHES IS
RELATIVELY COMMON. LATEST RAP SHOWS A MODEST BAND OF 850 HPA
FRONTOGENESIS RE-DEVELOPING ALONG THE MN/IA BORDER LATER THIS
MORNING. THIS LOWER LEVEL FORCING COMBINED WITH INCREASING
Q-VECTOR CONVERGENCE IN THE 500 TO 300 HPA LAYER ASSOCIATED WITH
THE APPROACHING CANADIAN TROUGH WILL RESULT IN 6-12 MORE HOURS OF
LIGHT SNOW ACROSS THE UPPER MS RIVER VALLEY.
LATEST REPORTS...MODEL/COBB DATA AND RADAR TRENDS PROVIDE ENOUGH
EVIDENCE TO JUSTIFY SOME CHANGES TO CURRENT HEADLINES. WILL EXTEND
THE WINTER STORM WARNING A TIER OF COUNTIES NORTHWARD FROM
MITCHELL TO CRAWFORD WHERE 6 TO 9 INCHES STORM TOTAL SNOW WILL
FALL. TO THE NORTH...WILL EXPAND THE WINTER WEATHER ADVISORY TO
INCLUDE THE I-90 CORRIDOR FROM OLMSTED TO JUNEAU/ADAMS COUNTIES
WHERE 3 TO 5 TOTAL INCHES ARE EXPECTED. FOR BOTH AREAS...THERE IS
LIKELY TO BE A SHARP GRADIENT IN SNOW AMOUNTS FROM NORTH TO SOUTH.
ALSO EXPECT AREAS OF BLOWING AND DRIFTING SNOW...ESPECIALLY ACROSS
WIND PRONE AREAS OF SOUTHEAST MN AND NORTHEAST IA GIVEN 30 TO 35
KTS AT THE TOP OF THE MIXED BOUNDARY LAYER. TRAVEL WILL REMAIN
DIFFICULT IF NOT HAZARDOUS FOR MUCH OF THE DAY.
ACCUMULATING SNOWFALL WILL QUICKLY TAPER OFF TO NOTHING NORTH OF
HIGHWAY 10 GIVEN VERY DRY AIRMASS ACROSS NORTHERN WI/MN WITH
SURFACE DEW POINTS DROPPING INTO THE TEENS TO LOWER 20S BELOW ZERO
ALONG THE CANADIAN BORDER. SNOW WILL SLOWLY DIMINISH AND MOVE OUT
OF THE REGION FROM NORTHWEST TO SOUTHEAST LATER THIS AFTERNOON.
TODAY WILL BE MARKEDLY COOLER WITH TEMPERATURES TOPPING OUT IN THE
TEENS...BUT WITH A STIFF NORTHERLY WIND...EXPECT WIND CHILL VALUES
IN THE SINGLE DIGITS BELOW ZERO. COLD CONDITIONS TO PERSIST
OVERNIGHT WITH CLEARING SKIES ALLOWING AIR TEMPERATURES TO DROP
BELOW ZERO. NORTHERLY WINDS FROM 5 TO 10 MPH WILL RESULT IN WIND
CHILLS FROM 10 TO 20 BELOW ZERO BY MONDAY MORNING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 323 AM CST SUN FEB 1 2015
TEMPERATURES TO REMAIN AT OR BELOW EARLY FEBRUARY NORMALS THROUGH
THE UPCOMING WORK WEEK WITH DAILY HIGHS FROM THE MID TEENS TO MID
20S AND LOWS FROM THE SINGLE DIGITS BELOW AND ABOVE ZERO.
AFTER A DRY MONDAY...SNOW CHANCES RETURN MONDAY NIGHT THROUGH
MID-WEEK AND THEN AGAIN BY EARLY NEXT WEEKEND. CONFIDENCE IN
STRENGTH AND TIMING OF THE RESPONSIBLE SHORT-WAVES IN NORTHWEST
FLOW ALOFT ARE AVERAGE AT BEST. GIVEN OVERALL DRIER AIR PARCEL
SOURCE REGION...SNOW ACCUMULATIONS THROUGH THE WEEK APPEAR TO BE
RELATIVELY MINOR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1100 PM CST SAT JAN 31 2015
SNOW HAS MOVED IN WITH DROPPING CIGS AND VSBYS. EXPECT KRST/KLSE TO
HOVER IN THE 1-2SM RANGE MOST OF THE TIME...WITH SOME DIP TO 1/2-
3/4SM AT KRST FROM TIME TO TIME. CIGS SHOULD HOLD NEAR 1 KFT...KRST
MOSTLY BELOW AND KLSE MOSTLY ABOVE.
THE BULK OF THE HEAVIER SNOWS WILL FALL THROUGH MID MORNING
SUNDAY...WITH GRADUAL IMPROVEMENT THROUGH THE REST OF THE DAY.
AMOUNTS NEAR 4 INCHES APPEAR LIKELY AT THIS TIME.
INCREASING PRESSURE GRADIENT WILL RESULT IN INCREASING WINDS/GUST
OVERNIGHT...PERSISTING INTO SUNDAY AFTERNOON. COULD BE SOME BLSN AT
KRST AS A RESULT...LIKELY CONTINUING SOME VSBY RESTRICTIONS EVEN
WHEN ACCUM SNOWS HAVE STOPPED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR WIZ061.
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
WIZ053>055.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
MNZ094>096.
IA...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR IAZ018-019-
029-030.
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
IAZ008>011.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
840 AM MST SUN FEB 1 2015
.SYNOPSIS...
IN THE WAKE OF AN EXITING LOW PRESSURE SYSTEM...AREAS OF FOG...
POTENTIALLY DENSE ACROSS THE SOUTH CENTRAL DESERTS...WILL BE
POSSIBLE THROUGH THE MORNING HOURS DUE TO ABUNDANT MOISTURE AND
CLEARING SKIES. HIGH PRESSURE WILL QUICKLY COVER THE AREA TODAY
BRINGING CLEARING SKIES...DRY WEATHER...AND WARMER TEMPERATURES. THE
DRY CONDITIONS WILL PERSIST THROUGH THE WEEK WHILE A WARMING TREND
ALLOWS FOR HIGHS TO REACH NEAR 80 DEGREES ACROSS THE LOWER DESERTS
BY THE END OF THE WORK WEEK.
&&
.DISCUSSION...
AFTER A RATHER WET COUPLE OF DAYS...WHICH HAS LEFT THE BOUNDARY
LAYER AND SOILS QUITE MOIST OVER SOUTH-CENTRAL AND SOUTHWEST
AZ...CLEAR SKIES EARLY THIS MORNING HAS ALLOWED DENSE FOG TO DEVELOP
OVER THE REGION. ALTHOUGH CLEAR SKIES ABOVE THIS FOG WILL ALLOW FOR
MAXIMUM SOLAR HEATING TODAY...IT APPEARS THAT BURN-OFF WILL TAKE
SOME TIME...WITH THE LATEST HRRR NOT SHOWING FULL CLEARING UNTIL
AROUND NOON...LIKELY DUE TO THE FACT THAT THE FOG LAYERS ARE RATHER
DEEP...WITH AIRCRAFT REPORTS INDICATING TOPS OF 700-1000FT AGL. ONCE
THE FOG DOES CLEAR...STILL EXPECTING MOSTLY CLEAR SKIES FOR THE REST
OF THE DAY AS HIGH PRESSURE CONTINUES TO BUILD OVER THE REGION.
OTHER THEN EXTENDING THE DENSE FOG ADVISORY UNTIL NOON AND MAKING
MINOR ADJUSTMENTS TO THE HOURLY TEMP AND DEWPOINT GRIDS...CURRENT
INHERITED FORECASTS STILL LOOK GOOD...NO FURTHER UPDATES ARE PLANNED
AT THIS TIME.
&&
.PREVIOUS DISCUSSION...
UPPER LOW THAT BROUGHT WIDESPREAD PRECIPITATION TO THE CENTRAL
DESERTS DURING THE PAST COUPLE OF DAYS HAS FINALLY SHIFTED OFF TO
THE SOUTHEAST...ALLOWING A SUBSIDENT NELY FLOW ALOFT TO OVERSPREAD
THE AREA. STRONG SUBSIDENCE ALOFT HAS BROUGHT CONSIDERABLE CLEARING
TO SOUTH CENTRAL AZ...AND IR IMAGERY AT 2 AM SHOWED GENLY CLEAR
SKIES FROM PHOENIX WESTWARD. A FEW MID/HIGH CLOUDS PERSISTED WELL TO
THE SOUTH AND EAST OF CENTRAL PHOENIX. ALTHOUGH MOISTURE HAS STARTED
TO THIN A BIT AS SEEN BY THE LATEST SOUNDINGS WHICH SHOWED PWAT
VALUES OF 0.86 AT SAN DIEGO AND 0.74 INCHES AT TUS...BOUNDARY LAYER
MOISTURE REMAINED HIGH AFTER ALL OF THE RAIN THAT HAS RECENTLY
FALLEN. SURFACE DEWPOINTS OVER THE DESERTS WERE RUNNING MOSTLY IN
THE UPPER 40S TO AROUND 50 AND RH VALUES WERE 100 PERCENT OR CLOSE
TO IT ACROSS MUCH OF THE CENTRAL DESERTS. OBSERVED AND FORECAST
SOUNDINGS FOR THIS MORNING SHOWED A VERY FAVORABLE DENSE FOG PROFILE
AND SPOTTER REPORTS AS WELL AS WEBCAMS HAVE BEEN INDICATING DENSE
FOG FORMING ACROSS THE SOUTHEAST VALLEY AND ACROSS NW PINAL COUNTY.
AS SUCH A DENSE FOG ADVISORY HAS BEEN ISSUED FOR NWRN/NCNTRL PINAL
COUNTY AS WELL AS THE GREATER PHOENIX AREA THRU 10 AM THIS MORNING.
WE MAY HAVE TO EXPAND THE ADVISORY INTO WESTERN MARICOPA COUNTY
SHOULD FOG DEVELOP OR SPREAD WESTWARD INTO THAT AREA. OTHERWISE...
EXPECT FOG TO DISSIPATE LATER THIS MORNING LEAVING MOSTLY SUNNY
SKIES ACROSS THE CENTRAL DESERTS. UNDER MOSTLY SUNNY SKIES...HIGH
TEMPS WILL BE ABLE TO CLIMB A HANDFUL OF DEGREES AND APPROACH
SEASONAL NORMALS.
MODEL GUIDANCE REMAINS VERY CONSISTENT IN CALLING FOR DRY AND WARMER
CONDITIONS FOR THE ENTIRE WEEK...AS A STRONG UPPER LEVEL HIGH
PRESSURE RIDGE STEADILY BUILDS INTO THE DESERT SOUTHWEST. AS THE
RIDGE BUILDS...THERE WILL BE PERIODS OF HIGH CLOUDS SPREADING
THROUGH THE RIDGE AND ACROSS THE DESERTS...BUT OVERALL WE SHOULD SEE
MOSTLY SUNNY DAYS AND MOSTLY CLEAR NIGHTS. HIGH TEMPS ARE FORECAST
TO CLIMB INTO THE MID TO UPPER 70S BY TUESDAY...THEN RISE FURTHER
AND INTO THE UPPER 70S TO LOW 80S ACROSS THE WARMER DESERTS BY
FRIDAY. H5 HEIGHTS ARE FORECAST TO RISE IN EXCESS OF 585DM OVER THE
SOUTHWEST AZ AND SERN CA DESERTS BY THIS WEEKEND AND WE COULD SEE
HIGH TEMPS REACH INTO THE MID TO UPPER 80S ACROSS THE WARMER LOWER
DESERTS AS A RESULT. WE HAVE RAISED OUR FORECAST HIGH TEMPS 2-3
DEGREES FOR THE LATTER PORTION OF THE WEEK AS A RESULT OF INCREASED
CONFIDENCE IN THE VERY WARM FORECAST CONDITIONS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...
FOG FORMATION WELL UNDERWAY ACROSS THE METRO AS OF 11Z AND KIWA HAS
BEEN VLIFR FOR SEVERAL HOURS ALREADY. SATELLITE INDICATING
DETERIORATING CONDITIONS IN THE NORTH/WEST VALLEY AND IT APPEARS
ITS ONLY A MATTER OF TIME BEFORE BOTH KPHX AND KSDL SEE FOG. GOING
TO INTRODUCE A PERIOD OF 1SM VSBYS AT BOTH LOCATIONS FROM APPROX
12Z-17Z TODAY. I EXPECT THE WORST CONDITIONS FROM DAYBREAK /14Z/
UNTIL MID MORNING WHEN BL MIXING SHOULD HELP BREAK THINGS UP.
CONDITIONS SHOULD IMPROVE RAPIDLY THROUGH THE AFTERNOON HOURS WITH
MINIMAL IMPACTS FORECAST BEYOND 20Z. AS FOR WINDS...LIGHT DIURNALLY
DRIVEN AT ALL SITES. VERY LIGHT EAST WINDS EXPECTED MONDAY MORNING.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NO MAJOR AVIATION IMPACTS FOR SOUTHEAST CALIFORNIA AS SKIES RAPIDLY
CLEAR. SFC WINDS WILL RETAIN A LIGHT NORTHERLY COMPONENT...THOUGH
COULD BECOME VARIABLE AT TIME AS THE PRESSURE GRADIENT WEAKENS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
WARMER TEMPERATURES ARE EXPECTED ACROSS THE REGION THIS WEEK ALONG
WITH DRIER AIR. DESPITE THIS...AFTERNOON HUMIDITIES WILL ONLY DROP
INTO THE 15-25 PERCENT RANGE EACH AFTERNOON WITH GOOD OVERNIGHT
RECOVERIES EXPECTED. NO MAJOR WIND EVENTS ARE ANTICIPATED WITH WINDS
FOLLOWING THE TYPICAL DIURNAL PATTERNS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...DENSE FOG ADVISORY UNTIL NOON TODAY FOR AZZ021>023-025>028.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA/CB
AVIATION...LEINS
FIRE WEATHER...LEINS
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NWS MELBOURNE FL
908 AM EST SUN FEB 1 2015
.DISCUSSION...
915 MHZ DATA FROM THE XMR AREA NETWORK SHOWS SLY COMPONENT FLOW HAS
BEEN IN PLACE BLO 3K FT FOR AROUND 7 HRS. THE MORNING SOUNDING FROM
XMR AND A REVIEW OF GPS SATELLITE DERIVED DATA INDICATE ONLY A
SLIGHT INCREASE IN PWAT THIS MORNING. PRIMARY OPEN CELL STRATO CU
OVER THE ATLC WATERS IS NOT EXPECTED TO PRODUCE MORE THAN WEAK RADAR
RETURNS OVER THE MARINE AREA THE REMAINDER OF THE AFTN. A DRY
FORECAST IS ALSO SUPPORTED BY THE LTST REGIONAL HRRR SOLN.
THE SURFACE HIGH PUSHING OFF OFFSHORE INTO THE SE ATLANTIC CST
WILL VEER WINDS TO THE SOUTHEAST. WINDS WILL INCREASE UP TO 10 TO 15
MPH WITH BREEZY CONDS ANTICIPATED ALONG THE TREASURE COAST.
SCATTERED MARINE STRATOCU WILL MOVE ONSHORE AND INLAND THROUGH THE
REMAINDER OF DAY WITH SKIES PARTLY SUNNY AND HIGHS REACHING THE LOW
TO MID 70S.
WINDS BECOME MORE SOUTHERLY INTO TONIGHT WITH MOISTURE INCREASING
AHEAD OF APPROACHING COLD FRONT ACROSS THE SOUTHEAST. MAY SEE A FEW
SHOWERS NORTH OF ORLANDO LATE TONIGHT AND OVER THE COASTAL WATERS.
OTHERWISE EXPECTING DRY CONDS WITH INCREASING CLOUD COVER OVERNIGHT.
LOWS WILL BE ABOVE NORMAL IN THE UPPER 50S TO LOW 60S.
&&
.AVIATION...(PREV DISC) VFR CONDS EXPECTED NEXT 24 HOURS. LOW LEVEL
ONSHORE WINDS WILL CONTINUE TO TRANSPORT SCT-BKN MARINE STRATOCU
ONSHORE WITH ANY BRIEF CIGS AOA 4K FT. SOUTHEAST WINDS 10-15 KTS
14Z WITH HIGHER GUSTS AT TIMES ALONG THE COAST. MAY NEED TO ADD A
PERIOD OF LLWS LATE TONIGHT THROUGH DAYBREAK MONDAY ACROSS NRN
TERMINALS DUE TO RAPIDLY INCREASING LOW LEVEL S/SW WINDS UP TO
AROUND 35 KTS AHEAD OF THE FRONT.
&&
.MARINE...
MODERATE TO FRESH ONSHORE BREEZE PERSISTS THROUGH THIS AFTERNOON
WITH SOUTHEAST WINDS. SEAS UP TO 6 FEET OVER THE GULF STREAM REQUIRE
CAUTION STMTS SOUTH OF THE CAPE.
WIND SPEEDS THEN CONTINUE TO INCREASE AS THEY BECOME MORE SOUTHERLY
INTO TONIGHT WITH BOATING CONDITIONS BECOMING HAZARDOUS OVER THE
OFFSHORE WATERS. WILL ISSUE A SCA STARTING OFFSHORE OF VOLUSIA
COUNTY LATE THIS EVENING...EXPANDING SOUTHWARD OVER THE OFFSHORE
WATERS LATE TONIGHT.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FROM 4 AM MONDAY TO 4 AM EST TUESDAY FOR
WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM
OFFSHORE-WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN
INLET 20 TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 4 PM EST MONDAY
FOR WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY
LINE 20 TO 60 NM OFFSHORE.
&&
$$
JP/TES
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
558 AM CST SUN FEB 1 2015
.SHORT TERM...
347 AM CST
THROUGH MONDAY...
HAVE BEEN SWAMPED THIS MORNING AND AM RUNNING BEHIND...SO GOING TO
KEEP DISCUSSION BRIEF THIS MORNING AND JUST HIT THE IMPORTANT
CHANGES. THE BIGGEST CHANGES TO GOING FORECAST IS THE UPGRADE TO
A BLIZZARD WARNING FOR PORTIONS OF NE IL/CHICAGO METRO AND TO
LOWER SNOW AMOUNTS AND ADD MIXED PRECIP BACK INTO GRIDS FAR SE
CWA.
GUIDANCE HAS CONTINUED TO TREND NORTH AND STRONGER WITH THE TRACK OF
THIS SYSTEM AND COMPARING GUIDANCE WITH SFC OBS AND BEST SFC
PRESSURE FALLS IT WOULD SEEM TO SUPPORT THE FARTHER NORTH TRACK THAT
THE RAP IN PARTICULAR HAS LATCHED ONTO. THE SOMEWHAT DEEPER LOW
ALONG WITH THE VERY STRONG ARCTIC HIGH SPREADING SOUTHEAST WILL
RESULT IN VERY STRONG WINDS DEVELOPING THIS AFTERNOON. INCREASING
LOW LEVEL COLD AIR ADVECTION AND SFC HEIGHT RISES FAVOR PRETTY GOOD
MIXING IN THE BOUNDARY LAYER...WHICH IS WHAT ALL MODEL FORECAST
SOUNDINGS ARE ADVERTISING. TAKING EVEN THE BEST CASE SCENARIO AND
ONE OF THE WEAKEST MODELS BUFKIT MOMENTUM TRANSFER VALUES SUPPORT
4-7 HOURS OF WIND GUSTS BETWEEN 35-40 MPH LATER THIS AFTERNOON AND
EVENING...WITH MORE AGGRESSIVE GFS/RAP SUPPORTING EVEN STRONGER
WINDS OVER A LONGER DURATION. SNOW HAS BEEN WET THUS FAR BUT WITH
TIME SHOULD SEE THE TRANSITION TOWARD DRIER/MORE BLOWABLE SNOW THIS
AFTERNOON FROM NORTH TO SOUTH AS THE COLUMN COOLS AND THE SNOW
LIQUID CONTENT DECREASES. BIGGEST UNCERTAINTY REVOLVES AROUND
REGARDING UPGRADE TO BLIZZARD WARNING WAS THE SNOW LIQUID CONTENT
AND PROBABILITY AND CONFIDENCE IS CERTAINLY HIGHER THE FARTHER NORTH
FROM I-80 THAT YOU GET...BUT EVEN AS FAR SOUTH AS I-80 FELT FAIRLY
CONFIDENT THAT WHITE OUT CONDITIONS COULD DEVELOP LATE THIS
AFTERNOON AND ESPECIALLY THIS EVENING. FARTHER WEST ACROSS NORTH
CENTRAL ILLINOIS FEEL THAT A BLIZZARD WARNING COULD EASILY BE
JUSTIFIED...BUT IN COORDINATION WITH MKX/DVN HAVE OPTED TO HOLD OFF
FOR NOW AS SNOW INTENSITY COULD BE DECREASING AS WINDS PICK UP.
QUITE POSSIBLE DAY SHIFT MAY NEED TO RE-ACCESS THIS AND AN UPGRADE
TO BLIZZARD WARNING FOR RFD AND POINTS WEST COULD OCCUR ON THE DAY
SHIFT.
OTHER BIG CHANGE TO FORECAST WAS TO ADD SLEET AND THEN DRIZZLE TO
THE FAR SOUTHEAST CWA. SFC TEMPS HAVE BEEN A BIT WARMER AND THE
FARTHER NORTH TRACK OF THE SFC LOW SHOULD KEEP LOW LEVEL WAA GOING
INTO EARLY AFTERNOON WITH AT LEAST THE THREAT OF MIXED
PRECIP...POSSIBLY TRANSITIONING OVER TO JUST DRIZZLE/SNIZZLE AS MID
LEVEL DRY SLOT OVERSPREADS THAT AREA REMOVING ICE NUCLEI FROM THE
CLOUDS LATE THIS AFTERNOON INTO THIS EVENING. THE WETTER SNOW SOUTH
OF I-80 SHOULD RESULT IN LESS SEVERE AND LESS IMPACTFUL
BLOWING/DRIFTING SNOW. GIVEN THE MARGINAL TEMPS AND POTENTIAL MIX
PRECIP HAVE CUT BACK ON ACCUMS IN THE FAR SOUTHEAST COUNTIES OF THE
CWA.
ACCUMULATING LAKE EFFECT POTENTIAL ACTUALLY LOOKS SOMEWHAT LESS
IMPRESSIVE THAN IT DID LAST NIGHT...AND IT WAS ALREADY LOOKING
MARGINAL. SOME SYSTEM SNOWS SHOULD LINGER INTO THIS EVENING BUT LAKE
CONTRIBUTIONS LOOK MINOR WITH LOW INVERSION HEIGHTS AND DECREASING
BOUNDARY LAYER RH AS THE THERMODYNAMICS IMPROVE EVER SO SLIGHTLY.
ANY LAKE ENHANCEMENT TO SNOW TOTALS SHOULD END UP BEING TRIVIAL.
FINALLY...GOING SNOWFALL TOTALS LOOK RIGHT ON TARGET AND MADE VERY
FEW CHANGES OTHER THAN IN SE AS NOTED ABOVE. A RESPECTABLY LARGE
SWATH OF A FOOT OR MORE OF SNOW STILL LOOKS LIKELY AND PROBABLY
CENTERED RELATIVELY CLOSE TO THE I-80 TO I-88/290 CORRIDORS.
ACTUALLY THINKING THAT MAX SNOWFALL TOTALS IN THE CWA COULD END UP
BEING ON THE HIGH END OF THE 10-14 INCH RANGE WITH LOCALIZED TOTALS
POTENTIALLY PUSHING A FOOT AND A HALF IF THE DEFO BAND IS INDEED AS
IMPRESSIVE AS SOME OF THE GUIDANCE WOULD SUGGEST. WHILE SNOWFALL
TOTALS WILL BE VERY IMPRESSIVE OVER MOST OF THE CWA...IT IS
IMPORTANT TO REMEMBER THE BLIZZARD WARNING IS ISSUED NOT FOR
SNOWFALL AMOUNTS BUT RATHER FOR VISIBILITY AND WINDS. THE CRITERIA
FOR BLIZZARD WARNING IS 3+ HOURS OF LESS THAN 1/4SM VSBY IN FALLING
AND/OR BLOWING SNOW ALONG WITH SUSTAINED WINDS OR FREQUENT GUSTS
OVER 35 MPH.
IZZI
&&
.LONG TERM...
MONDAY NIGHT THROUGH SATURDAY...
134 AM...FORECAST CONCERNS INCLUDE A CHANCE OF LIGHT SNOW MONDAY
NIGHT INTO TUESDAY...THEN A BETTER CHANCE FOR ACCUMULATING LIGHT
SNOW TUESDAY NIGHT INTO WEDNESDAY MORNING.
A RIDGE OF HIGH PRESSURE WILL BE MOVING SOUTHEAST OF THE AREA
MONDAY EVENING AS A WEAK WAVE MOVES ACROSS THE REGION MONDAY NIGHT.
FAIRLY LIGHT QPF FROM ALL THE MODELS WITH THIS WAVE BUT PLENTY COLD
ENOUGH FOR THE LOW QPF AMOUNTS TO POTENTIALLY FLUFF UP TO A HALF
INCH MONDAY NIGHT. WHILE TEMPS BY THIS TIME WILL LIKELY BE IN THE
SINGLE DIGITS OR LOW TEENS...CLOUD COVER AND WEAK WARM AIR ADVECTION
MAY ALLOW TEMPS TO HOLD STEADY OR RISE A FEW DEGREES OVERNIGHT.
NEXT WAVE QUICKLY SHIFTS SOUTHEAST ACROSS THE AREA BY TUESDAY
EVENING WITH QPF AMOUNTS BETWEEN ONE AND TWO TENTHS. THIS HAS BEEN
A FAIRLY CONSISTENT FEATURE ON THE MODELS AND IF THIS MATERIALIZES
AS ADVERTISED...A FEW INCHES OF SNOW WILL BE POSSIBLE. TIMING AND
LOCATION ALSO ARE A BIT UNCERTAIN...EARLIER COULD IMPACT THE TUESDAY
EVENING RUSH...LATER COULD IMPACT THE WEDNESDAY MORNING RUSH. BUT
GIVEN THE POTENTIAL FOR SOME ACCUMULATION...OPTED TO BUMP POPS UP TO
LIKELY FOR TUESDAY NIGHT.
HIGH PRESSURE THEN SETTLES SOUTH ACROSS THE MIDWEST AND LAKES REGION
WEDNESDAY INTO THURSDAY AND WITH IT...SOME VERY COLD AIR. WITH A
DEEP SNOWPACK BY THAT TIME AND DIMINISHING WINDS WEDNESDAY NIGHT
INTO THURSDAY...EXPECT MANY LOCATIONS TO DROP BELOW ZERO FOR LOWS
THURSDAY MORNING. THE AIRMASS MODIFIES/WARMS SOME THURSDAY BUT
STILL EXPECTING LOWS IN THE LOWER SINGLE DIGITS THURSDAY EVENING...
POSSIBLY BELOW ZERO BUT WARM AIR ADVECTION BY MORNING WITH
INCREASING SOUTHERLY WINDS MAY PUT THE BRAKES ON HOW LOW TEMPS FALL
THURSDAY NIGHT. STRONG SOUTHERLY WINDS CONTINUE INTO SATURDAY WITH
WARMING TEMPS...THAT WILL LIKELY BE MUTED SOME BY THE SNOWPACK. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* SNOW THROUGH TOMORROW MORNING. PREVAILING VIS UNDER 1SM THROUGH
THIS EVENING. VIS ARND 1/2SM THROUGH EARLY EVENING.
* NELY WINDS INCREASING THROUGH THE MORNING...GUSTING TO 30-35KT
THIS AFTERNOON. OCNL HIGHER GUSTS POSSIBLE.
* BLOWING AND DRIFTING SNOW LIKELY THIS AFTERNOON AND TONIGHT.
* PERIODS OF VIS 1/4SM OR LESS THIS AFTERNOON WHEN GUSTS INCREASE
TO 30KT AND HIGHER.
* IFR-LIFR CIGS THROUGH LATE EVENING.
KREIN
//DISCUSSION...UPDATED 12Z...
LONG DURATION SNOW EVENT UNDERWAY AS LOW PRESSURE OVER MISSOURI
MOVES EAST THROUGH SOUTHERN ILLINOIS AND INDIANA BY THIS EVENING
AS IT SLOWLY STRENGTHENS. MOISTURE STREAMING NORTH FROM THE GULF
OF MEXICO WILL ALLOW THIS SYSTEM TO PRODUCE MODERATE SNOW THROUGH
THIS EVENING...BEFORE SLOWLY TAPERING OFF LATE TONIGHT INTO EARLY
MONDAY MORNING. VISIBILITIES WILL LIKELY FLUCTUATE WITH HEAVIER
BANDS OF SNOW...BUT PREVAILING VIS LIKELY TO BE AROUND 1/2SM FOR
MUCH OF THE EVENT. AS WINDS STRENGTHEN WITH GUSTS OF 30-35KT...OR
POSSIBLY HIGHER...THIS AFTERNOON AND EARLY EVENING...VIS COULD
DROP TO 1/4SM OR LOWER IN PERIODS OF HEAVIER SNOWFALL AND STRONGER
WIND GUSTS. WINDS WILL TURN MORE NORTHERLY LATE THIS EVENING AND
THEN BEGIN TO DIMINISH EARLY MONDAY MORNING AS HIGH PRESSURE
BUILDS IN FROM THE WEST.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM TO HIGH CONFIDENCE IN WX/VIS TRENDS.
* MEDIUM CONFIDENCE IN CIG TRENDS.
* MEDIUM CONFIDENCE IN TIMING OF IMPROVING CIG/VIS.
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR/WX NIL EARLY. CHANCE SNOW WITH MVFR CIGS/VIS
LATE.
TUESDAY...SLIGHT CHANCE SNOW EARLY WITH MVFR CIGS/VIS. VFR/WX NIL
AFTERNOON. SNOW LIKELY WITH IFR CIG/VIS OVERNIGHT.
WEDNESDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS EARLY. VFR/WX NIL
OVERNIGHT.
THURSDAY...VFR/WX NIL.
FRIDAY...VFR/WX NIL.
SATURDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS POSSIBLE.
KREIN
&&
.MARINE...
315 AM CST
THE SFC LOW OVER THE PLAINS LOOKS TO BE DEEPENING A LITTLE FASTER
AND LOWER WHILE THE HIGH PRESSURE RIDGING OVER THE UPPER GREAT
LAKES IS TRENDING A LITTLE STRONGER. THIS COMBINATION WITH STRONG
COLD ADVECTION SETTING UP OVER THE LAKE TODAY...HAVE EXPANDED THE
GALE WARNING OVER THE ENTIRE OPEN WATERS OF LAKE MICHIGAN AS WELL
AS EXTENDING IN TIME...STARTING A LITTLE EARLIER...AT 15Z THIS
MORNING AND GOING A LITTLE LATER...TO 09Z TONIGHT. ALSO...HAVE
INCREASED GALES TO 40KT OVER THE SOUTHERN PORTIONS OF THE LAKE
WHERE THE PRESSURE GRADIENT AND PRESSURE FALLS ARE STRONGEST. AS
THE WINDS PICK UP TO GALE FORCE AND MUCH COLDER AIR FILTERS OVER
THE LAKE LATER TODAY...HEAVY FREEZING SPRAY WILL BE LIKELY...SO
HAVE ALSO ISSUED A HEAVY FREEZING SPRAY WARNING FROM 15Z THIS
MORNING TO 09Z TONIGHT. THE COLDER AIR WILL SPREAD OVER THE
NORTHERN PORTIONS OF THE LAKE EARLIER THAN THE SOUTHERN
PORTIONS...SO IT IS POSSIBLE THAT THE HEAVY FREEZING SPRAY
POTENTIAL MAY NOT REACH THE SOUTHERN PORTIONS OF THE LAKE UNTIL
THIS AFTERNOON...BUT WENT WITH ONE SEGMENT TO THE WARNING TO
COINCIDE WITH THE GALE WARNING TIMING. THE LOW SHOULD PUSH EAST
INTO THE MID ATLANTIC REGION BE MONDAY AFTERNOON...WHILE HIGH
PRESSURE SPREADS ACROSS THE MISSISSIPPI RIVER INTO THE WESTERN
GREAT LAKES REGION. THIS WILL LEAD TO SUBSIDING WINDS AND
WAVES...ESPECIALLY AS WEAK HIGH PRESSURE PRESSURE CROSSES THE LAKE
MONDAY NIGHT AND TUESDAY.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WARNING...ILZ005-ILZ006-ILZ011-ILZ012-ILZ013-ILZ014-
ILZ020-ILZ022 UNTIL 2 PM SUNDAY.
LAKESHORE FLOOD ADVISORY...ILZ006-ILZ014...2 PM SUNDAY TO 10 AM
MONDAY.
BLIZZARD WARNING...ILZ005-ILZ006-ILZ011-ILZ012-ILZ013-ILZ014-
ILZ020-ILZ022...2 PM SUNDAY TO MIDNIGHT MONDAY.
WINTER STORM WARNING...ILZ003-ILZ004-ILZ008-ILZ010-ILZ019-ILZ021-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL MIDNIGHT MONDAY.
IN...BLIZZARD WARNING...INZ001...2 PM SUNDAY TO MIDNIGHT MONDAY.
WINTER STORM WARNING...INZ001 UNTIL 2 PM SUNDAY.
WINTER STORM WARNING...INZ002-INZ010-INZ011-INZ019 UNTIL
MIDNIGHT MONDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878...9 AM SUNDAY TO 3 AM MONDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 AM SUNDAY TO
3 AM MONDAY.
SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 9 AM SUNDAY.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
526 AM CST SUN FEB 1 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 221 AM CST SUN FEB 1 2015
MAIN FORECAST CONCERN IS ADDITIONAL SNOW ACCUMULATION THIS MORNING
AND NEAR-BLIZZARD CONDITIONS EXPECTED LATE THIS MORNING AND MUCH
OF THE AFTERNOON.
LATEST RADAR SCANS SHOWS THAT THE SNOW IS BEGINNING TO WANE
OVERALL. SOME EMBEDDED STRONGER SNOW BANDS ARE PRESENT NEAR
SCHUYLER/NORTH BEND WITH ANOTHER ENHANCED AREA DRIFTING NORTHEAST
TO THE OMAHA/CB METRO AREA. METARS ARE SHOWING VISIBILITIES
GENERALLY 1 TO 2 MILES. WE DID HEAR OF ONE REPORT OF THUNDER...BUT
NEVER DID SEE THAT SHOW UP IN THE LIGHTNING DETECTION NET. THUS
FAR SNOW AMOUNTS HAVE BEEN AVERAGING 4 TO 9 INCHES IN THE WINTER
STORM WARNING AREA. MANY AREAS PROBABLY WON`T ACHIEVE THE WINTER
STORM CRITERIA AMOUNT OF 8 INCHES. BUT...WE FEEL THE WINTER STORM
WARNING REMAINS JUSTIFIED DUE TO THE EXTREMELY POOR ROAD
CONDITIONS BEING REPORTED AND THE EXPECTED NEAR-BLIZZARD
CONDITIONS POSSIBLE TODAY WHEN THE WINDS KICK IN. FOR THE
REMAINDER OF THIS MORNING...MOISTURE PROFILES REMAIN DEEP AND
STILL WELL LOCATED WITHIN THE DENDRITIC GROWTH ZONE. THUS SNOW
PRODUCTION REMAINS GOOD...THOUGH OVERALL SYSTEM LIFT IS PULLING
OUT TO THE NORTHEAST. FOR NOW THROUGH THIS AFTERNOON ANOTHER 1 TO
3 INCHES APPEARS LIKELY ACROSS THE COUNTY WARNING AREA WITH THE
HIGHEST AMOUNTS FOCUSED ACROSS EAST-CENTRAL NEBRASKA AND WESTERN
IOWA.
AS OF 9Z WINDS HAVE ALREADY PICKED UP AT OFK/LCG/ONL AND EXPECT
ALL AREAS TO BE VERY WINDY BY LATE THIS MORNING. RUC SOUNDINGS
SUGGEST DECENT MIXING MAY OCCUR THIS AFTERNOON AND WIND GUSTS OVER
40 MPH AREN`T OUT OF THE QUESTION. NOT SURE IF THE STRONGEST WINDS
WILL BE SUSTAINED LONG ENOUGH ALONG WITH LOW VISIBILITIES TO
NECESSITATE A BLIZZARD WARNING. CONDITIONS WILL SURELY BE VERY
POOR...THUS WE ADDED NEAR-BLIZZARD WORDING TO THE LATEST WINTER
STORM WARNING UPDATE. THE SNOW SHOULD BE FINISHED JUST AFTER
SUNSET THIS EVENING AND WINDS WILL STEADILY DECREASE OVERNIGHT AS
WEAK SURFACE HIGH PRESSURE SETTLES IN OVER THE AREA. DECIDED TO
LOWER OVERNIGHT LOWS A FEW DEGREES GIVEN SIGNIFICANT SNOW COVER IN
PLACE.
LOOKS LIKE DRY WEATHER FOR MONDAY AND MONDAY NIGHT. BY TUESDAY A
WEAK CLIPPER SYSTEM TRACKS ACROSS NORTHEAST NEBRASKA AND NORTHWEST
IOWA. SOME LIGHT SNOW MAY OCCUR...OPTED FOR LOW CHANCES FOR NOW.
AS THIS FEATURE MOVES EAST IT STRENGTHENS AND OUR FAR NORTHEASTERN
COUNTIES COULD PICK UP A COUPLE INCHES OF SNOW DURING THE DAY ON
TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 221 AM CST SUN FEB 1 2015
NORTHWEST FLOW ALOFT WILL CONTINUE THROUGH THE END OF THE WEEK
BEFORE A MORE ZONAL FLOW PATTERN SETS UP BY SATURDAY. ONE
SIGNIFICANT SHORTWAVE ROLLING THROUGH THE FLOW WILL BRING ANOTHER
CHANCE FOR SNOW TUESDAY NIGHT AND WEDNESDAY WITH COLDER HIGH
PRESSURE SETTLING INTO THE PLAINS FOLLOWING SHORTWAVE. TIMING AND
TRACK OF SNOW WITH THIS SHORTWAVE IS STILL IN QUESTION...BUT MODELS
SEEM TO BE COMING TOGETHER SOMEWHAT IN SHOWING MUCH OF EASTERN
NEBRASKA AND SOUTHWEST IOWA GETTING LIGHT SNOW AT SOME POINT TUESDAY
NIGHT OR WEDNESDAY. AMOUNTS SHOULD REMAIN IN THE INCH OR TWO RANGE
GIVEN LOWER MOISTURE CONTENT AND PROGRESSIVE MOVEMENT. LOWS TUESDAY
NIGHT IN THE TEENS WILL ONLY GAIN A FEW DEGREES INTO THE 20S
WEDNESDAY GIVEN CLOUDS/PRECIP AND A SWITCH TO NORTHERLY WINDS.
COLDER AIR SETTLING SOUTH BEHIND SHORTWAVE WILL GIVE US A COLD START
THURSDAY MORNING WITH LOWS IN THE SINGLE DIGITS...WITH SOME SUB-ZERO
READINGS LIKELY.
A QUICK REBOUND STILL LOOKS ON TRACK THURSDAY WITH WINDS BECOMING
SOUTHERLY...WHICH CONTINUE FRIDAY AND SATURDAY. THUS A SLIGHT
WARMING TREND IS FORECAST...CLIMBING FROM THE 20S THURSDAY TO THE
30S AND PERHAPS LOWER 40S FRIDAY AND SATURDAY.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 523 AM CST SUN FEB 1 2015
IFR TO LIFR CIGS/VSBYS IN SNOW AND BLOWING SNOW ARE EXPECTED
THROUGH THIS AFTERNOON. SNOWFALL WILL GRADUALLY DECREASE THROUGH
THE DAY...BUT NORTH WINDS GUSTING TO 35KT WILL CREATE OCCASIONAL
VSBYS AT OR BELOW 1SM. WINDS SHOULD DECREASE INTO THE 15 TO 25KT
RANGE BETWEEN 22Z AND 02Z...THEN DECREASE TO LESS THAN 10KT BY
06Z. CIGS SHOULD IMPROVE TO MVFR BY 00Z...THEN SCATTER OUT BEFORE
06Z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ011-
016-017-030-031-090>093.
WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ012-015-
018-032>034-042>045-050>053-065>068-078-088-089.
IA...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR IAZ043-055-
056-069-080-091.
WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR IAZ079-090.
&&
$$
SHORT TERM...PEARSON
LONG TERM...DERGAN
AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS PORTLAND OR
221 AM PST SUN FEB 1 2015
.SYNOPSIS...HIGH PRES ALOFT WILL CONTINUE TO SHIFT EAST TODAY AS A
WEAK WEATHER SYSTEM APPROACHES THE COAST. THE OFFSHORE LOW-LEVEL FLOW
WILL GRADUALLY WEAKEN DURING THE DAY...LIKELY SHIFTING TO WEAK
ONSHORE BY LATE AFTERNOON. THE FRONTAL SYSTEM IS EXPECTED TO REACH
THE COAST THIS MORNING THEN REACH THE CASCADES BY THE AFTERNOON.
OVERALL PRECIPITATION AMOUNTS WILL BE RATHER LIGHT. A MUCH WETTER
SYSTEM IMPACTS THE AREA LATE SUNDAY NIGHT AND MONDAY. COMPUTER MODEL
SOLUTIONS SHOW HIGH VARIABILITY TUESDAY THROUGH THURSDAY...BUT THE
MOST LIKELY SCENARIO IS A BRIEF DRYING TREND WEDNESDAY AND WEDNESDAY
NIGHT...FOLLOWED BY A RETURN TO A MUCH WETTER PATTERN LATE IN THE
WEEK.
&&
.SHORT TERM...TODAY THROUGH TUESDAY...MAIN STORY EARLY THIS MORNING
IS THE LOW-LEVEL OFFSHORE FLOW. AT 0930Z THE KTTD-KDLS GRADIENT WAS
AT -6.4 MB...SLIGHTLY HIGHER THAN THE 03-HR FORECAST FROM THE 06Z NAM
RUN. THIS GRADIENT IS PRODUCING WIND GUSTS OF 40-50 MPH AT THE WEST
END OF THE COLUMBIA GORGE...BUT UP TO 65 MPH AT CROWN POINT. THESE
GUSTS ARE DOWN ABOUT 10 MPH FROM LATE SAT EVENING. THE COOL POOL
APPEARS TO BE A BIT DEEPER THAN MODELS SUGGEST...AS EVIDENCED BY THE
26F DEGREE READING AT A RAWS SITE AT 3450 FT MSL IN THE S WA
CASCADES. THE OFFSHORE GRADIENT IS BEING SUPPLEMENTED BY AN
APPROACHING WEAK FRONTAL SYSTEM...ALLOWING LOWERING PRESSURE
OFFSHORE FOR INCREASING GRADIENTS. THE 06Z NAM ELIMINATES THE
OFFSHORE GRADIENT BY 21Z TODAY...BUT IT TENDS TO WEAKEN THE OFFSHORE
FLOW TOO SOON. WOULD EXPECT THE EAST WIND TO DIE OFF MORE TOWARD 00Z
OR EVEN EARLY THIS EVENING.
KRTX DUAL-POL DOPPLER RADAR SHOWING SOME PRECIP ECHOES NEARING THE
COAST AS OF 0930Z. THE MID AND HIGH CLOUD COVER HAS LIMITED FOG
FORMATION. KEUG HAD DROPPED TO ONE-QUARTER MILE EARLIER BUT HAS COME
UP TO JUST OVER 2 MILES VISIBILITY SHORTLY BEFORE 10Z. NOT MUCH
CHANGE TO THE SUNDAY FORECAST. MODELS AGREE THAT PRECIP ALONG THE
COAST SHOULD COMMENCE AROUND 12-14Z AND THEN SPREAD INLAND.
INITIALLY...THE LOW-LEVEL OFFSHORE FLOW WILL SLOW THE MOISTENING
PROCESS OF THE COLUMN...THUS NOT EXPECTING PRECIP TO BEGIN AT KPDX
UNTIL AROUND 16-18Z. THE 08Z HRRR SHOWS PRECIP BY 16Z...BUT BELIEVE
THIS MAY BE A BIT TOO SOON. IN ANY EVENT...PRECIP WITH THIS FRONTAL
SYSTEM WILL BE RATHER LIGHT...MAYBE ONE-QUARTER TO ONE-HALF INCH
TOTAL FOR THE COAST RANGE...WILLAPA HILLS AND CASCADES. PRECIP LIKELY
TO BEGIN AS SNOW IN EASTERN SKAMANIA COUNTY OF SW WA AND THE EAST
SIDE OF MT. HOOD DUE TO THE RELATIVELY DEEP COOL POOL. THIS SYSTEM
MAY NOT BE STRONG ENOUGH TO TOTALLY MIX OUT THE COLDER AIR IN THOSE
AREAS. ANY PRECIP IN THE UPPER HOOD RIVER VALLEY SHOULD STAY AS
LIQUID.
MODELS ALSO IN GENERAL AGREEMENT REGARDING THE SUN NIGHT/MON SYSTEM.
MAIN MODEL DISCREPANCIES LIE IN THE TIMING AND FOCUS OF THE HEAVIEST
QPF. THE ECMWF SEEMS TO BE A BIT FASTER AND KEEPS THE HEAVIEST QPF
OVER SWRN OREGON MON MORNING. GFS HAS THE QPF BULLS-EYE A LITTLE
FURTHER NORTH WHILE THE NAM IS JUST A TOUCH MORE N THAN THE GFS. NAM
ALSO ALSO DEVELOPS A SLIGHTLY STRONGER SURFACE LOW NEAR BUOY 029 18Z
MON WHILE THE GFS HAS IT A BIT WEAKER AND FURTHER N. BREEZY TO WINDY
SOUTH WIND WOULD DEVELOP IF THE NAM VERIFIES...ESPECIALLY ALONG THE
COAST. NAM ALSO SHOWS A SHARPER AND MORE DYNAMIC COLD FRONT. THIS
WOULD ALSO BREAK THROUGH VALLEY INVERSIONS AND WARM UP THE LOWLANDS
CONSIDERABLY...JUST BEFORE COLD FRONTAL PASSAGE. IN ADDITION...00Z
NAM BUFR SOUNDINGS SHOW THE POTENTIAL FOR SOME INSTABILITY...WITH
CAPE OF 400-800 J/KG JUST ABOVE LOW-LEVEL INVERSION. THERE IS THE
SLIM POTENTIAL MONDAY AFTERNOON FOR SOME SURFACE-BASED CONVECTION
WITH THE COLD FRONT. THE SOUNDINGS ALSO SHOW DECENT DIRECTIONAL
SHEAR WITHIN THE UNSTABLE LAYER. HAVE MAINTAINED THE SLIGHT CHANCE
OF THUNDER MONDAY AFTERNOON AND EARLY EVENING.
TOTAL QPF FOR THIS SYSTEM EXPECTED TO BE ON THE ORDER OF 1 TO 1.5
INCHES FOR THE MOUNTAINS AND 0.25 TO 0.75 FOR THE LOWLANDS. MODELS
THEN START TO DIVERGE MON NIGHT AND BEYOND. THE ECMWF BRINGS A WARM
FRONT INTO SWRN OREGON TUE MORNING....AS DOES THE NAM BUT IT HAS IT A
LITTLE MORE TO THE S...CLOSER TO THE CALIFORNIA BORDER. THE GFS IS
MORE IN BETWEEN THE TWO. THIS WARM FRONTAL FEATURE GRADUALLY DRIFTS N
TUE AFTERNOON...BUT STAYS S OF THE COLUMBIA RIVER BY 00Z WED.
THUS...SNOW LEVELS WILL BE MUCH LOWER IN THE S WA AND FAR N OREGON
CASCADES TUE...COMPARED TO AREAS S OF MT. JEFFERSON. WEISHAAR
LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...MODELS SOLUTIONS VARY IN
THE MID-WEEK PERIOD. THE GFS INDICATES AN UPPER RIDGE RETURNING TO
THE PACIFIC NW WED WHILE THE ECMWF KEEPS A REMNANT WARM-FRONTAL
BAROCLINIC BOUNDARY OVER THE REGION. THERE IS A THE GEM IS MORE IN
LINE WITH THE GFS COMPARED TO THE ECMWF. MADE SOME SMALL ADJUSTEMENTS
TO THE WED AND WED NIGHT PERIODS...MAINLY TO TRIM POPS A BIT. SHOULD
THE GFS PAN OUT...FURTHER REDUCTION WOULD BE NECESSARY AND WOULD ALSO
NEED TO CONSIDER THE INCLUSION OF NIGHT NIGHT AND MORNING FOG FOR THE
INTERIOR VALLEYS. MODELS ARE IN SURPRISING AGREEMENT FOR THE END OF
THE EXTENDED PERIOD. IT LOOKS LIKE A PERIOD OF MUCH WETTER WEATHER
WILL IMPACT THE REGION LATE IN THE WEEK...AND POSSIBLY INTO NEXT
WEEKEND AS A SWATH OF SUBTROPICAL MOISTURE COMBINED WITH A SERIES OF
ATMOSPHERIC WAVES SETS UP OVER THE NE PACIFIC. THIS WEATHER PATTERN
WILL LIKELY BRING A SUBSTANTIAL AMOUNT OF RAIN TO PARTS OF THE
PACIFIC NORTHWEST. HOWEVER...CONFIDENCE IN TIMING AND AREAS OF
PRIMARY QPF FOCUS REMAIN RATHER LOW AT THIS TIME. WEISHAAR
&&
.AVIATION...THE COAST AS WELL AS NORTH AND CENTRAL WILLAMETTE
VALLEY SITES REMAINS VFR AS COLD FRONT APPROACHES THE REGION.
INCREASING CLOUDS EARLY THIS MORNING WILL LIMIT FOG DEVELOPMENT IN
THESE AREAS...THOUGH THERE IS SOME PATCHY FOG AROUND KSLE
OCCASIONALLY REDUCING CIGS/VSBYS AT THIS SITE. CIGS WILL
GRADUALLY LOWER OVER NIGHT WITH RAIN DEVELOPING AROUND 14Z ALONG
THE COAST AND CLOSER TO 16Z AT SITES IN THE WILLAMETTE VALLEY.
FURTHER SOUTH...LIFR CIGS/VSBYS AT KEUG WILL CONTINUE UNTIL
SHOWERS START TO PUSH INTO THE REGION AROUND 16Z. CIGS/VSBYS WILL
GRADUALLY IMPROVE TO MVFR AFTER FRONTAL PASSAGE THIS
AFTERNOON/EVENING.
KPDX AND APPROACHES...VFR CONDITIONS WILL PREVAIL THIS MORNING WITH
GUSTY EAST WINDS. MID AND HIGH CLOUDS INCREASE OVERNIGHT WITH
CIGS FALLING FROM 100 TO 050 AROUND 16Z SUN ALONG WITH RAIN
DEVELOPING. MAY SEE IFR CIGS WORK SOUTH ALONG THE I-5 CORRIDOR
FROM THE KKLS AREA TOWARD KPDX BUT EASTERLY OUTFLOW FROM THE GORGE
SHOULD KEEP IT AS AN IFR STRATUS DECK IF IT ARRIVES AT ALL. RAIN
PICKS UP AROUND 16Z AND CIGS FALL TO 025. EXPECT FRONTAL PASSAGE
AND A TRANSITION TO SHOWERS NEAR 23Z. -MCCOY/JBONK
&&
.MARINE...AN APPROACHING COLD FRONT IS APPROACHING OUR WATERS THIS
MORNING AND WILL MOVE THROUGH THIS MORNING. WINDS WILL INCREASE
NEAR SMALL CRAFT ADVISORY ALONG AND AHEAD OF THE FRONT THIS
MORNING. CONFIDENCE IS STILL LOW THAT GUSTS ABOVE 20 KTS WILL BE
PREVALENT ENOUGH TO WARRANT A SMALL CRAFT ADVISORY...THOUGH A FEW
GUSTS OVER 20 KTS ARE POSSIBLE...ESPECIALLY AS THE FRONT NEARS
SHORE. SEAS START TO INCREASE WITH THIS SYSTEM BUT LOOK TO REMAIN
BELOW 10 FT TODAY. A SECOND...STRONGER SYSTEM MOVES THROUGH ON
MONDAY...BRINGING A VERY GOOD CHANCE FOR SMALL CRAFT WINDS WITH
GUSTS TO 30 KTS LIKELY. THIS SYSTEM WILL ALSO INCREASE SEAS TO 10
TO 12 FT. WINDS AND SEAS START TO SUBSIDE LATE MONDAY...BRINGING
SEAS BACK DOWN TO AROUND 7 TO 8 FT BY MIDWEEK AS SHORT-LIVED HIGH
PRESSURE BUILDS BACK OVER THE REGION. MODELS ARE IN AGREEMENT THAT
AN EVEN STRONGER SYSTEM WILL MOVE THROUGH LATE THIS WEEK...WHICH
COULD GENERATE SOUTHERLY GALES AND BRING SEAS UP TO NEAR 20 FT
THURSDAY OR FRIDAY. THERE IS UNCERTAINTY IN THE TIMING AND TRACK
OF THIS SYSTEM...WHICH SHOULD GET IRONED OUT AS THE WEEK
PROGRESSES. -MCCOY
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
$$
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
NWS STATE COLLEGE PA
1043 AM EST SUN FEB 1 2015
.SYNOPSIS...
LOW PRESSURE WILL CROSS THE CENTRAL MISSISSIPPI RIVER VALLEY
TODAY AND MOVE INTO THE OHIO VALLEY TONIGHT...AND CROSS THE STATE
ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION
ACROSS THE AREA THIS AFTERNOON INTO MONDAY. A PERIOD OF FREEZING
RAIN IS LIKELY ACROSS THE SOUTH AND CENTRAL SECTIONS TONIGHT.
ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY AFTERNOON INTO
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONLY SOME REALLY PATCHY AND LIGHT SNOW IS FALLING OVER THE WRN
HALF OF THE AREA. BUT SOME MORE-INTENSE BANDS MOVING OVER PBZ/S
AREA AND INTO THE LAURELS ATTM. THESE SHOULD MAKE SOME
ACCUMULATIONIN THE WEST/CENTRAL COS BY MID- AFTERNOON...BUT THE
SUN IS MANAGING TO MAKE A BRIGHT SPOT IN THE CLOUDS OVER STATE
COLLEGE RIGHT NOW. IT IS STILL SNOWING WITH VSBY LT 4SM.
BUT...ANYTHING MORE THAN A FEW TENTHS OF SNOW ACCUM ARE UNLIKELY
BEFORE MID AFTN. MESO MDLS HINT AT A BREAK AFTER A FEW BANDS OF
SNOW SLIDE SW-NE THRU THE AREA THIS AFTN...THEN THE SNOW MOVES
BACK IN AND INTENSIFIES FROM SW-NE THIS EVENING. ALL THIS IS
PRETTY MUCH UNCHANGED.
WITH THAT SAID...
WITH EACH PASSING MODEL CYCLE IT LOOKS LIKE WE WILL GET LESS SNOW
ON THE WHOLE...WHETHER DUE TO LOWER QPF DUE TO ONLY A COUPLE OF
HEAVIER BANDS AND PERHAPS ONLY ONE 3-6 HR PERIOD OF HEAVY SNOW -
OR DUE TO MORE RAIN/MIX OCCURRING IN THE SOUTHERN HALF OF THE
AREA. HOWEVER...IT HAS BARELY STARTED SNOWING. LETS AT LEAST LET
IT START TO PLAY OUT. WILL NOT MAKE ANY TWEAKS TO SNOW OR ICE
ACCUMS OR CHANGES TO HEADLINES AT THIS POINT. BUT THE LATER
UPDATES TODAY MAY JUST FOLLOW THIS MILDER/DRIER TREND IF THE
NEWER GFS AND EC LOOK SIMILARLY MILD AND LESS WET.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
LOW PRESSURE MOVES UP THE OHIO RIVER TONIGHT. BY MONDAY MORNING
IT SHOULD BE OVER KPIT...AND ROLL OVER THE SOUTHERN HALF OF THE
LOCAL AREA. MAIN QPF FALLS IN THE 03Z TO 09Z TIMEFRAME FOR MANY...
AND THIS SIX HOUR PERIOD WILL BE CRITICAL FOR SNOW ACCUMS OVER THE
CENTRAL MOUNTAINS...JUST NORTH OF THE CHANGEOVER ZONE. FASTER/
GREATER MIXING WILL DECREASE SNOW AMOUNTS SUBSTANTIALLY. FOR NOW
HAVE NUDGED THE MIXING ZONE NORTH AND DECREASED SNOW AMOUNTS SOUTH
OF INTERSTATE 80 INTO THE 4-6" RANGE. AS A RESULT...GREATER FZRA
POTENTIAL EXISTS WITH THIS SOLUTION THAN PREVIOUS THINKING.
WHILE THE FARTHER NORTH/WARMER SOLUTION WILL CUT DOWN THE SNOW
AMOUNTS IN THE CENTRAL ZONES...WARNING CRITERIA SNOWFALL IS
EXPECTED NORTH OF INTERSTATE 80. ADVY AND SUB ADVISORY SNOW
AMOUNTS ARE EXPECTED ACROSS THE SOUTHERN THIRD OF CENTRAL PA...
BUT THE CHANCE FOR ICING IS ENOUGH TO WARRANT AT LEAST AN ADVY
FOR THEM.
SFC LOW RAPIDLY TRACKS EAST OF THE AREA BY MIDDAY MONDAY...WITH
COLDER AIR POURING BACK INTO THE COMMONWEALTH ON THE BACKSIDE OF
THE LOW. EXPECT LITTLE IF ANY ADDITIONAL SNOW ACCUMULATION BY MON
AFTERNOON ACROSS THE NORTH. PRECIP WILL HAVE SHUT OFF ACROSS
CENTRAL AND SOUTHERN AREAS BY MIDDAY. SHARPLY COLDER AIR IS POISED
TO OVERSPREAD CENTRAL PA AGAIN ON MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY
MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD
NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW
ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY
DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP
WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND
LAUREL HIGHLANDS LIKELY NEEDING A WIND CHILL ADVISORY /-15F/ MON
NIGHT INTO EARLY TUE. THIS COULD ADD TO STORM-RELATED
IMPACTS...INCLUDING POTENTIAL FOR PATCHY BLACK ICE.
HIGH PRESSURE WILL BRING COLD BUT GENERALLY QUIET WEATHER INTO
MIDWEEK. A WEAK SYSTEM MOVES THROUGH WED THAT MAY BRING LIGHT
ACCUMS TO THE NW HALF /BEFORE THE SYSTEM DEEPENS MORE RAPIDLY OVER
NEW ENGLAND/...WHICH WILL BE FOLLOWED BY A SHOT OF MORE ARCTIC AIR
AS COLD HIGH PRESSURE BUILDS IN FOR THU INTO FRI - INCLUDING A
RETURN OF BELOW ZERO WIND CHILLS.
TEMPS MODERATE A BIT...BUT REMAIN BELOW NORMAL...ON SAT. ANOTHER
LOW PRESSURE AREA MAY IMPACT THE REGION ON SUNDAY...BUT AT THIS
TIME IT LOOKS TO BE ON THE WEAKER SIDE.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
DETERIORATING FLYING CONDS EXPECTED THIS AFTN AND EVENING...AS LOW
PRES APPROACHES FROM THE MIDWEST...SPREADING SNOW AND LOWERING
CIGS ACROSS CENTRAL PA. AT 15Z...IFR CONDS ALREADY NOTED ACROSS
WESTERN PA. UPSTREAM RADAR RETURNS AND LATEST HRRR OUTPUT SUGGESTS
IFR CONDS WILL DEVELOP AT KAOO/KUNV ARND 16Z AND AT KIPT ARND
18Z. ACROSS THE SOUTHEAST COUNTIES...SOME MINOR VIS REDUCTIONS
APPEAR LIKELY THIS AFTN IN LGT SNOW. HOWEVER...IFR CONDS WILL LKLY
HOLD OFF AT KMDT/KLNS UNTIL LATE THIS EVENING.
WARMER AIR WORKING INTO THE STATE WILL CHANGE SNOW TO EITHER RAIN
OR FZRA ACROSS THE SOUTHERN HALF OF THE STATE LATE TONIGHT.
HOWEVER....WIDESPREAD IFR TO LIFR CONDS EXPECTED EVERYWHERE IN
CONTINUING PRECIP AND LOW CIGS RESULTING FROM MOIST SE FLOW
ASCENDING THE HIGHER TERRAIN OF CENTRAL PA. LLWS REMAINS A
POSSIBILITY LATE TONIGHT ACROSS THE S/SE AS LOW LEVEL JET ROTATES
THROUGH.
MARKED IMPROVEMENT IS EXPECTED BTWN 15Z-18Z MONDAY...AS LOW PRES
PASSES EAST OF THE AREA...AND DRIER NW FLOW DEVELOPS.
OUTLOOK...
MON...REDUCED CONDS EARLY...GRADUALLY IMPROVING AS THE STORM
MOVES AWAY FROM THE AREA. LLWS POSS MON AFT/NIGHT.
TUE...NO SIG WX.
WED...MVFR IN SHSN NW...VFR SE.
THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR PAZ004>006-
010>012-017>019-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY UNTIL 8 AM EST MONDAY FOR PAZ033>036-
064>066.
WINTER STORM WARNING UNTIL 8 AM EST MONDAY FOR PAZ024>028-056-
057-059-063.
&&
$$
SYNOPSIS...DANGELO/DEVOIR
NEAR TERM...DANGELO
SHORT TERM...DEVOIR
LONG TERM...RXR
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1042 AM EST SUN FEB 1 2015
.SYNOPSIS...
LOW PRESSURE WILL CROSS THE CENTRAL MISSISSIPPI RIVER VALLEY
TODAY AND MOVE INTO THE OHIO VALLEY TONIGHT...AND CROSS THE STATE
ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION
ACROSS THE AREA THIS AFTERNOON INTO MONDAY. A PERIOD OF FREEZING
RAIN IS LIKELY ACROSS THE SOUTH AND CENTRAL SECTIONS TONIGHT.
ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY AFTERNOON INTO
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BROKEN SHIELD OF LIGHT SNOW DEVELOPING WELL OUT AHEAD OF SFC LOW
OVER EASTERN KANSAS THIS MORNING...ALONG A COLD FRONTAL BOUNDARY
DROPPING SOUTHWARD ACROSS THE EASTERN GREAT LAKES AND OHIO VALLEY.
THE AFOREMENTIONED LOW PRESSURE CENTER WILL TRACK ALONG THIS
BOUNDARY THIS AFTERNOON AND TONIGHT...AND ACROSS THE SOUTHERN TIER
OF PENNSYLVANIA BY MONDAY MORNING.
EXPANDED POPS SLIGHTLY EARLY THIS MORNING AS RADAR TRENDS INDICATE
A FEW POCKETS OF LIGHT SNOW WILL REACH INTO THE LOWER SUSQ FOR A
TIME THIS MORNING. BACK EDGE OF INITIAL SNOWFALL LIES ACROSS
CENTRAL OH/IN THIS MORNING...AND EXPECT THIS LULL TO REACH INTO
AT LEAST PORTIONS OF CENTRAL AND SOUTHERN PA FOR A GOOD PART OF
THIS AFTERNOON.
ALL HEADLINES RETAINED FOR THIS FORECAST CYCLE. MAIN CONCERNS ARE
THAT POPS WERE TOO HIGH TO BEGIN THE STORM THIS AFTERNOON...WHERE
ONLY VERY LIGHT AMOUNTS OF QPF AND SNOW ARE EXPECTED. IN
FACT...HI RES HRRR AND HRW-ARW CONTINUE TO SHOW FRACTURED
MOTHEATEN PRECIP SHIELD DECREASING BY AFTERNOON...WITH A FEW TO
SEVERAL HOURS IN BETWEEN IN AND MAIN PRECIP EVENT SPINNING UP THIS
EVENING AS SFC LOW PUSHES INTO THE OHIO VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
LOW PRESSURE MOVES UP THE OHIO RIVER TONIGHT. BY MONDAY MORNING
IT SHOULD BE OVER KPIT...AND ROLL OVER THE SOUTHERN HALF OF THE
LOCAL AREA. MAIN QPF FALLS IN THE 03Z TO 09Z TIMEFRAME FOR MANY...
AND THIS SIX HOUR PERIOD WILL BE CRITICAL FOR SNOW ACCUMS OVER THE
CENTRAL MOUNTAINS...JUST NORTH OF THE CHANGEOVER ZONE. FASTER/
GREATER MIXING WILL DECREASE SNOW AMOUNTS SUBSTANTIALLY. FOR NOW
HAVE NUDGED THE MIXING ZONE NORTH AND DECREASED SNOW AMOUNTS SOUTH
OF INTERSTATE 80 INTO THE 4-6" RANGE. AS A RESULT...GREATER FZRA
POTENTIAL EXISTS WITH THIS SOLUTION THAN PREVIOUS THINKING.
WHILE THE FARTHER NORTH/WARMER SOLUTION WILL CUT DOWN THE SNOW
AMOUNTS IN THE CENTRAL ZONES...WARNING CRITERIA SNOWFALL IS
EXPECTED NORTH OF INTERSTATE 80. ADVY AND SUB ADVISORY SNOW
AMOUNTS ARE EXPECTED ACROSS THE SOUTHERN THIRD OF CENTRAL PA...
BUT THE CHANCE FOR ICING IS ENOUGH TO WARRANT AT LEAST AN ADVY
FOR THEM.
SFC LOW RAPIDLY TRACKS EAST OF THE AREA BY MIDDAY MONDAY...WITH
COLDER AIR POURING BACK INTO THE COMMONWEALTH ON THE BACKSIDE OF
THE LOW. EXPECT LITTLE IF ANY ADDITIONAL SNOW ACCUMULATION BY MON
AFTERNOON ACROSS THE NORTH. PRECIP WILL HAVE SHUT OFF ACROSS
CENTRAL AND SOUTHERN AREAS BY MIDDAY. SHARPLY COLDER AIR IS POISED
TO OVERSPREAD CENTRAL PA AGAIN ON MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY
MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD
NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW
ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY
DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP
WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND
LAUREL HIGHLANDS LIKELY NEEDING A WIND CHILL ADVISORY /-15F/ MON
NIGHT INTO EARLY TUE. THIS COULD ADD TO STORM-RELATED
IMPACTS...INCLUDING POTENTIAL FOR PATCHY BLACK ICE.
HIGH PRESSURE WILL BRING COLD BUT GENERALLY QUIET WEATHER INTO
MIDWEEK. A WEAK SYSTEM MOVES THROUGH WED THAT MAY BRING LIGHT
ACCUMS TO THE NW HALF /BEFORE THE SYSTEM DEEPENS MORE RAPIDLY OVER
NEW ENGLAND/...WHICH WILL BE FOLLOWED BY A SHOT OF MORE ARCTIC AIR
AS COLD HIGH PRESSURE BUILDS IN FOR THU INTO FRI - INCLUDING A
RETURN OF BELOW ZERO WIND CHILLS.
TEMPS MODERATE A BIT...BUT REMAIN BELOW NORMAL...ON SAT. ANOTHER
LOW PRESSURE AREA MAY IMPACT THE REGION ON SUNDAY...BUT AT THIS
TIME IT LOOKS TO BE ON THE WEAKER SIDE.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
DETERIORATING FLYING CONDS EXPECTED THIS AFTN AND EVENING...AS LOW
PRES APPROACHES FROM THE MIDWEST...SPREADING SNOW AND LOWERING
CIGS ACROSS CENTRAL PA. AT 15Z...IFR CONDS ALREADY NOTED ACROSS
WESTERN PA. UPSTREAM RADAR RETURNS AND LATEST HRRR OUTPUT SUGGESTS
IFR CONDS WILL DEVELOP AT KAOO/KUNV ARND 16Z AND AT KIPT ARND
18Z. ACROSS THE SOUTHEAST COUNTIES...SOME MINOR VIS REDUCTIONS
APPEAR LIKELY THIS AFTN IN LGT SNOW. HOWEVER...IFR CONDS WILL LKLY
HOLD OFF AT KMDT/KLNS UNTIL LATE THIS EVENING.
WARMER AIR WORKING INTO THE STATE WILL CHANGE SNOW TO EITHER RAIN
OR FZRA ACROSS THE SOUTHERN HALF OF THE STATE LATE TONIGHT.
HOWEVER....WIDESPREAD IFR TO LIFR CONDS EXPECTED EVERYWHERE IN
CONTINUING PRECIP AND LOW CIGS RESULTING FROM MOIST SE FLOW
ASCENDING THE HIGHER TERRAIN OF CENTRAL PA. LLWS REMAINS A
POSSIBILITY LATE TONIGHT ACROSS THE S/SE AS LOW LEVEL JET ROTATES
THROUGH.
MARKED IMPROVEMENT IS EXPECTED BTWN 15Z-18Z MONDAY...AS LOW PRES
PASSES EAST OF THE AREA...AND DRIER NW FLOW DEVELOPS.
OUTLOOK...
MON...AM RAIN/SNOW AND LOW CIGS. PM GUSTY NW WINDS.
TUE...NO SIG WX EXPECTED.
WED...AM LGT SNOW POSSIBLE NW MTNS.
THU...LGT SNOW POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR PAZ004>006-
010>012-017>019-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY UNTIL 8 AM EST MONDAY FOR PAZ033>036-
064>066.
WINTER STORM WARNING UNTIL 8 AM EST MONDAY FOR PAZ024>028-056-
057-059-063.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...RXR
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1018 AM EST SUN FEB 1 2015
.SYNOPSIS...
LOW PRESSURE WILL CROSS THE CENTRAL MISSISSIPPI RIVER VALLEY
TODAY AND MOVE INTO THE OHIO VALLEY TONIGHT...AND CROSS THE STATE
ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION
ACROSS THE AREA THIS AFTERNOON INTO MONDAY. A PERIOD OF FREEZING
RAIN IS LIKELY ACROSS THE SOUTH AND CENTRAL SECTIONS TONIGHT.
ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY AFTERNOON INTO
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BROKEN SHIELD OF LIGHT SNOW DEVELOPING WELL OUT AHEAD OF SFC LOW
OVER EASTERN KANSAS THIS MORNING...ALONG A COLD FRONTAL BOUNDARY
DROPPING SOUTHWARD ACROSS THE EASTERN GREAT LAKES AND OHIO VALLEY.
THE AFOREMENTIONED LOW PRESSURE CENTER WILL TRACK ALONG THIS
BOUNDARY THIS AFTERNOON AND TONIGHT...AND ACROSS THE SOUTHERN TIER
OF PENNSYLVANIA BY MONDAY MORNING.
EXPANDED POPS SLIGHTLY EARLY THIS MORNING AS RADAR TRENDS INDICATE
A FEW POCKETS OF LIGHT SNOW WILL REACH INTO THE LOWER SUSQ FOR A
TIME THIS MORNING. BACK EDGE OF INITIAL SNOWFALL LIES ACROSS
CENTRAL OH/IN THIS MORNING...AND EXPECT THIS LULL TO REACH INTO
AT LEAST PORTIONS OF CENTRAL AND SOUTHERN PA FOR A GOOD PART OF
THIS AFTERNOON.
ALL HEADLINES RETAINED FOR THIS FORECAST CYCLE. MAIN CONCERNS ARE
THAT POPS WERE TOO HIGH TO BEGIN THE STORM THIS AFTERNOON...WHERE
ONLY VERY LIGHT AMOUNTS OF QPF AND SNOW ARE EXPECTED. IN
FACT...HI RES HRRR AND HRW-ARW CONTINUE TO SHOW FRACTURED
MOTHEATEN PRECIP SHIELD DECREASING BY AFTERNOON...WITH A FEW TO
SEVERAL HOURS IN BETWEEN IN AND MAIN PRECIP EVENT SPINNING UP THIS
EVENING AS SFC LOW PUSHES INTO THE OHIO VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
LOW PRESSURE MOVES UP THE OHIO RIVER TONIGHT. BY MONDAY MORNING
IT SHOULD BE OVER KPIT...AND ROLL OVER THE SOUTHERN HALF OF THE
LOCAL AREA. MAIN QPF FALLS IN THE 03Z TO 09Z TIMEFRAME FOR MANY...
AND THIS SIX HOUR PERIOD WILL BE CRITICAL FOR SNOW ACCUMS OVER THE
CENTRAL MOUNTAINS...JUST NORTH OF THE CHANGEOVER ZONE. FASTER/
GREATER MIXING WILL DECREASE SNOW AMOUNTS SUBSTANTIALLY. FOR NOW
HAVE NUDGED THE MIXING ZONE NORTH AND DECREASED SNOW AMOUNTS SOUTH
OF INTERSTATE 80 INTO THE 4-6" RANGE. AS A RESULT...GREATER FZRA
POTENTIAL EXISTS WITH THIS SOLUTION THAN PREVIOUS THINKING.
WHILE THE FARTHER NORTH/WARMER SOLUTION WILL CUT DOWN THE SNOW
AMOUNTS IN THE CENTRAL ZONES...WARNING CRITERIA SNOWFALL IS
EXPECTED NORTH OF INTERSTATE 80. ADVY AND SUB ADVISORY SNOW
AMOUNTS ARE EXPECTED ACROSS THE SOUTHERN THIRD OF CENTRAL PA...
BUT THE CHANCE FOR ICING IS ENOUGH TO WARRANT AT LEAST AN ADVY
FOR THEM.
SFC LOW RAPIDLY TRACKS EAST OF THE AREA BY MIDDAY MONDAY...WITH
COLDER AIR POURING BACK INTO THE COMMONWEALTH ON THE BACKSIDE OF
THE LOW. EXPECT LITTLE IF ANY ADDITIONAL SNOW ACCUMULATION BY MON
AFTERNOON ACROSS THE NORTH. PRECIP WILL HAVE SHUT OFF ACROSS
CENTRAL AND SOUTHERN AREAS BY MIDDAY. SHARPLY COLDER AIR IS POISED
TO OVERSPREAD CENTRAL PA AGAIN ON MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY
MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD
NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW
ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY
DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP
WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND
LAUREL HIGHLANDS LIKELY NEEDING A WIND CHILL ADVISORY /-15F/ MON
NIGHT INTO EARLY TUE. THIS COULD ADD TO STORM-RELATED
IMPACTS...INCLUDING POTENTIAL FOR PATCHY BLACK ICE.
HIGH PRESSURE WILL BRING COLD BUT GENERALLY QUIET WEATHER INTO
MIDWEEK. A WEAK SYSTEM MOVES THROUGH WED THAT MAY BRING LIGHT
ACCUMS TO THE NW HALF /BEFORE THE SYSTEM DEEPENS MORE RAPIDLY OVER
NEW ENGLAND/...WHICH WILL BE FOLLOWED BY A SHOT OF MORE ARCTIC AIR
AS COLD HIGH PRESSURE BUILDS IN FOR THU INTO FRI - INCLUDING A
RETURN OF BELOW ZERO WIND CHILLS.
TEMPS MODERATE A BIT...BUT REMAIN BELOW NORMAL...ON SAT. ANOTHER
LOW PRESSURE AREA MAY IMPACT THE REGION ON SUNDAY...BUT AT THIS
TIME IT LOOKS TO BE ON THE WEAKER SIDE.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
DETERIORATING FLYING CONDS EXPECTED THIS AFTN AND EVENING...AS LOW
PRES APPROACHES FROM THE MIDWEST...SPREADING SNOW AND LOWERING
CIGS ACROSS CENTRAL PA. AT 15Z...IFR CONDS ALREADY NOTED ACROSS
WESTERN PA. UPSTREAM RADAR RETURNS AND LATEST HRRR OUTPUT SUGGESTS
IFR CONDS WILL DEVELOP AT KAOO/KUNV ARND 16Z AND AT KIPT ARND
18Z. ACROSS THE SOUTHEAST COUNTIES...SOME MINOR VIS REDUCTIONS
APPEAR LIKELY THIS AFTN IN LGT SNOW. HOWEVER...IFR CONDS WILL LKLY
HOLD OFF AT KMDT/KLNS UNTIL LATE THIS EVENING.
WARMER AIR WORKING INTO THE STATE WILL CHANGE SNOW TO EITHER RAIN
OR FZRA ACROSS THE SOUTHERN HALF OF THE STATE LATE TONIGHT.
HOWEVER....WIDESPREAD IFR TO LIFR CONDS EXPECTED EVERYWHERE IN
CONTINUING PRECIP AND LOW CIGS RESULTING FROM MOIST SE FLOW
ASCENDING THE HIGHER TERRAIN OF CENTRAL PA. LLWS REMAINS A
POSSIBILITY LATE TONIGHT ACROSS THE S/SE AS LOW LEVEL JET ROTATES
THROUGH.
MARKED IMPROVEMENT IS EXPECTED BTWN 15Z-18Z MONDAY...AS LOW PRES
PASSES EAST OF THE AREA...AND DRIER NW FLOW DEVELOPS.
OUTLOOK...
MON...REDUCED CONDS EARLY...GRADUALLY IMPROVING AS THE STORM
MOVES AWAY FROM THE AREA. LLWS POSS MON AFT/NIGHT.
TUE...NO SIG WX.
WED...MVFR IN SHSN NW...VFR SE.
THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR PAZ004>006-
010>012-017>019-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY UNTIL 8 AM EST MONDAY FOR PAZ033>036-
064>066.
WINTER STORM WARNING UNTIL 8 AM EST MONDAY FOR PAZ024>028-056-
057-059-063.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...RXR
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
712 AM EST SUN FEB 1 2015
.SYNOPSIS...
LOW PRESSURE WILL CROSS THE CENTRAL MISSISSIPPI RIVER VALLEY
TODAY AND MOVE INTO THE OHIO VALLEY TONIGHT...AND CROSS THE STATE
ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION
ACROSS THE AREA THIS AFTERNOON INTO MONDAY. A PERIOD OF FREEZING
RAIN IS LIKELY ACROSS THE SOUTH AND CENTRAL SECTIONS TONIGHT.
ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY AFTERNOON INTO
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BROKEN SHIELD OF LIGHT SNOW DEVELOPING WELL OUT AHEAD OF SFC LOW
OVER EASTERN KANSAS THIS MORNING...ALONG A COLD FRONTAL BOUNDARY
DROPPING SOUTHWARD ACROSS THE EASTERN GREAT LAKES AND OHIO VALLEY.
THE AFOREMENTIONED LOW PRESSURE CENTER WILL TRACK ALONG THIS
BOUNDARY THIS AFTERNOON AND TONIGHT...AND ACROSS THE SOUTHERN TIER
OF PENNSYLVANIA BY MONDAY MORNING.
EXPANDED POPS SLIGHTLY EARLY THIS MORNING AS RADAR TRENDS INDICATE
A FEW POCKETS OF LIGHT SNOW WILL REACH INTO THE LOWER SUSQ FOR A
TIME THIS MORNING. BACK EDGE OF INITIAL SNOWFALL LIES ACROSS
CENTRAL OH/IN THIS MORNING...AND EXPECT THIS LULL TO REACH INTO
AT LEAST PORTIONS OF CENTRAL AND SOUTHERN PA FOR A GOOD PART OF
THIS AFTERNOON.
ALL HEADLINES RETAINED FOR THIS FORECAST CYCLE. MAIN CONCERNS ARE
THAT POPS WERE TOO HIGH TO BEGIN THE STORM THIS AFTERNOON...WHERE
ONLY VERY LIGHT AMOUNTS OF QPF AND SNOW ARE EXPECTED. IN
FACT...HI RES HRRR AND HRW-ARW CONTINUE TO SHOW FRACTURED
MOTHEATEN PRECIP SHIELD DECREASING BY AFTERNOON...WITH A FEW TO
SEVERAL HOURS IN BETWEEN IN AND MAIN PRECIP EVENT SPINNING UP THIS
EVENING AS SFC LOW PUSHES INTO THE OHIO VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
LOW PRESSURE MOVES UP THE OHIO RIVER TONIGHT. BY MONDAY MORNING
IT SHOULD BE OVER KPIT...AND ROLL OVER THE SOUTHERN HALF OF THE
LOCAL AREA. MAIN QPF FALLS IN THE 03Z TO 09Z TIMEFRAME FOR MANY...
AND THIS SIX HOUR PERIOD WILL BE CRITICAL FOR SNOW ACCUMS OVER THE
CENTRAL MOUNTAINS...JUST NORTH OF THE CHANGEOVER ZONE. FASTER/
GREATER MIXING WILL DECREASE SNOW AMOUNTS SUBSTANTIALLY. FOR NOW
HAVE NUDGED THE MIXING ZONE NORTH AND DECREASED SNOW AMOUNTS SOUTH
OF INTERSTATE 80 INTO THE 4-6" RANGE. AS A RESULT...GREATER FZRA
POTENTIAL EXISTS WITH THIS SOLUTION THAN PREVIOUS THINKING.
WHILE THE FARTHER NORTH/WARMER SOLUTION WILL CUT DOWN THE SNOW
AMOUNTS IN THE CENTRAL ZONES...WARNING CRITERIA SNOWFALL IS
EXPECTED NORTH OF INTERSTATE 80. ADVY AND SUB ADVISORY SNOW
AMOUNTS ARE EXPECTED ACROSS THE SOUTHERN THIRD OF CENTRAL PA...
BUT THE CHANCE FOR ICING IS ENOUGH TO WARRANT AT LEAST AN ADVY
FOR THEM.
SFC LOW RAPIDLY TRACKS EAST OF THE AREA BY MIDDAY MONDAY...WITH
COLDER AIR POURING BACK INTO THE COMMONWEALTH ON THE BACKSIDE OF
THE LOW. EXPECT LITTLE IF ANY ADDITIONAL SNOW ACCUMULATION BY MON
AFTERNOON ACROSS THE NORTH. PRECIP WILL HAVE SHUT OFF ACROSS
CENTRAL AND SOUTHERN AREAS BY MIDDAY. SHARPLY COLDER AIR IS POISED
TO OVERSPREAD CENTRAL PA AGAIN ON MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY
MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD
NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW
ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY
DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP
WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND
LAUREL HIGHLANDS LIKELY NEEDING A WIND CHILL ADVISORY /-15F/ MON
NIGHT INTO EARLY TUE. THIS COULD ADD TO STORM-RELATED
IMPACTS...INCLUDING POTENTIAL FOR PATCHY BLACK ICE.
HIGH PRESSURE WILL BRING COLD BUT GENERALLY QUIET WEATHER INTO
MIDWEEK. A WEAK SYSTEM MOVES THROUGH WED THAT MAY BRING LIGHT
ACCUMS TO THE NW HALF /BEFORE THE SYSTEM DEEPENS MORE RAPIDLY OVER
NEW ENGLAND/...WHICH WILL BE FOLLOWED BY A SHOT OF MORE ARCTIC AIR
AS COLD HIGH PRESSURE BUILDS IN FOR THU INTO FRI - INCLUDING A
RETURN OF BELOW ZERO WIND CHILLS.
TEMPS MODERATE A BIT...BUT REMAIN BELOW NORMAL...ON SAT. ANOTHER
LOW PRESSURE AREA MAY IMPACT THE REGION ON SUNDAY...BUT AT THIS
TIME IT LOOKS TO BE ON THE WEAKER SIDE.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
LOWERING CONDITIONS WILL OCCUR FROM WEST TO EAST...BEGINNING SO
FAR AT BFD AND JST AT LIFR AND IFR RESPECTIVELY AS DEEPENING
MOISTURE /AND THE ONSET OF LIGHT SNOW/ STREAKS EASTWARD ALONG AND
AHEAD OF A SLOWLY SWD SAGGING COLD FRONT.
WIDESPREAD IFR TO LIFR CONDITIONS ARE IN STORE THIS
AFTERNOON...OVERNIGHT AND INTO EARLY MON AS HEAVIER SNOW IMPACTS
THE NORTHERN HALF OF THE STATE. THE SOUTHERN HALF WILL SEE A
WINTRY MIX WORK INTO THE SOUTHERN TAF SITES...FROM JST AND
AOO...TO KMDT- KLNS AREA WITH POTENTIAL FOR ICING. THIS IS DUE TO
WARM AIR ADVECTION INTO THE MID LEVELS...AND COLD TEMPERATURES AT
THE SURFACE. LLWS POSS SUNDAY NIGHT ACROSS THE S/SE AS LOW LEVEL
JET ROTATES THROUGH.
OUTLOOK...
SUN...WIDESPREAD IFR-MVFR CIGS AND IFR VSBYS DEVELOPING DURING THE
MORNING-EARLY AFTERNOON HOURS. LLWS POSS SUN NIGHT SE.
MON...REDUCED CONDS EARLY...GRADUALLY IMPROVING AS THE STORM
MOVES AWAY FROM THE AREA. LLWS POSS MON AFT/NIGHT.
TUE...NO SIG WX.
WED...MVFR IN SHSN NW...VFR SE.
THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR PAZ004>006-
010>012-017>019-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY UNTIL 8 AM EST MONDAY FOR PAZ033>036-
064>066.
WINTER STORM WARNING UNTIL 8 AM EST MONDAY FOR PAZ024>028-056-
057-059-063.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...RXR
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
621 AM EST SUN FEB 1 2015
.SYNOPSIS...
LOW PRESSURE WILL CROSS THE CENTRAL MISSISSIPPI RIVER VALLEY
TODAY AND MOVE INTO THE OHIO VALLEY TONIGHT...AND CROSS THE STATE
ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION
ACROSS THE AREA THIS AFTERNOON INTO MONDAY. A PERIOD OF FREEZING
RAIN IS LIKELY ACROSS THE SOUTH AND CENTRAL SECTIONS TONIGHT.
ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY AFTERNOON INTO
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BROKEN SHIELD OF LIGHT SNOW DEVELOPING WELL OUT AHEAD OF SFC LOW
OVER EASTERN KANSAS THIS MORNING...ALONG A COLD FRONTAL BOUNDARY
DROPPING SOUTHWARD ACROSS THE EASTERN GREAT LAKES AND OHIO VALLEY.
THE AFOREMENTIONED LOW PRESSURE CENTER WILL TRACK ALONG THIS
BOUNDARY THIS AFTERNOON AND TONIGHT...AND ACROSS THE SOUTHERN TIER
OF PENNSYLVANIA BY MONDAY MORNING.
EXPANDED POPS SLIGHTLY EARLY THIS MORNING AS RADAR TRENDS INDICATE
A FEW POCKETS OF LIGHT SNOW WILL REACH INTO THE LOWER SUSQ FOR A
TIME THIS MORNING. BACK EDGE OF INITIAL SNOWFALL LIES ACROSS
CENTRAL OH/IN THIS MORNING...AND EXPECT THIS LULL TO REACH INTO
AT LEAST PORTIONS OF CENTRAL AND SOUTHERN PA FOR A GOOD PART OF
THIS AFTERNOON.
ALL HEADLINES RETAINED FOR THIS FORECAST CYCLE. MAIN CONCERNS ARE
THAT POPS WERE TOO HIGH TO BEGIN THE STORM THIS AFTERNOON...WHERE
ONLY VERY LIGHT AMOUNTS OF QPF AND SNOW ARE EXPECTED. IN
FACT...HI RES HRRR AND HRW-ARW CONTINUE TO SHOW FRACTURED
MOTHEATEN PRECIP SHIELD DECREASING BY AFTERNOON...WITH A FEW TO
SEVERAL HOURS IN BETWEEN IN AND MAIN PRECIP EVENT SPINNING UP THIS
EVENING AS SFC LOW PUSHES INTO THE OHIO VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
LOW PRESSURE MOVES UP THE OHIO RIVER TONIGHT. BY MONDAY MORNING
IT SHOULD BE OVER KPIT...AND ROLL OVER THE SOUTHERN HALF OF THE
LOCAL AREA. MAIN QPF FALLS IN THE 03Z TO 09Z TIMEFRAME FOR MANY...
AND THIS SIX HOUR PERIOD WILL BE CRITICAL FOR SNOW ACCUMS OVER THE
CENTRAL MOUNTAINS...JUST NORTH OF THE CHANGEOVER ZONE. FASTER/
GREATER MIXING WILL DECREASE SNOW AMOUNTS SUBSTANTIALLY. FOR NOW
HAVE NUDGED THE MIXING ZONE NORTH AND DECREASED SNOW AMOUNTS SOUTH
OF INTERSTATE 80 INTO THE 4-6" RANGE. AS A RESULT...GREATER FZRA
POTENTIAL EXISTS WITH THIS SOLUTION THAN PREVIOUS THINKING.
WHILE THE FARTHER NORTH/WARMER SOLUTION WILL CUT DOWN THE SNOW
AMOUNTS IN THE CENTRAL ZONES...WARNING CRITERIA SNOWFALL IS
EXPECTED NORTH OF INTERSTATE 80. ADVY AND SUB ADVISORY SNOW
AMOUTNS ARE EXPECTED ACROSS THE SOUTHERN THIRD OF CENTRAL PA...
BUT THE CHANCE FOR ICING IS ENOUGH TO WARRANT AT LEAST AN ADVY
FOR THEM.
SFC LOW RAPIDLY TRACKS EAST OF THE AREA BY MIDDAY MONDAY...WITH
COLDER AIR POURING BACK INTO THE COMMONWEALTH ON THE BACKSIDE OF
THE LOW. EXPECT LITTLE IF ANY ADDITIONAL SNOW ACCUMULATION BY MON
AFTERNOON ACROSS THE NORTH. PRECIP WILL HAVE SHUT OFF ACROSS
CENTRAL AND SOUTHERN AREAS BY MIDDAY. SHARPLY COLDER AIR IS POISED
TO OVERSPREAD CENTRAL PA AGAIN ON MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY
MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD
NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW
ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY
DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP
WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND
LAUREL HIGHLANDS LIKELY NEEDING A WIND CHILL ADVISORY /-15F/ MON
NIGHT INTO EARLY TUE. THIS COULD ADD TO STORM-RELATED
IMPACTS...INCLUDING POTENTIAL FOR PATCHY BLACK ICE.
HIGH PRESSURE WILL BRING COLD BUT GENERALLY QUIET WEATHER INTO
MIDWEEK. A WEAK SYSTEM MOVES THROUGH WED THAT MAY BRING LIGHT
ACCUMS TO THE NW HALF /BEFORE THE SYSTEM DEEPENS MORE RAPIDLY OVER
NEW ENGLAND/...WHICH WILL BE FOLLOWED BY A SHOT OF MORE ARCTIC AIR
AS COLD HIGH PRESSURE BUILDS IN FOR THU INTO FRI - INCLUDING A
RETURN OF BELOW ZERO WIND CHILLS.
TEMPS MODERATE A BIT...BUT REMAIN BELOW NORMAL...ON SAT. ANOTHER
LOW PRESSURE AREA MAY IMPACT THE REGION ON SUNDAY...BUT AT THIS
TIME IT LOOKS TO BE ON THE WEAKER SIDE.
&&
.AVIATION /11Z SUNDAY THROUGH THURSDAY/...
THE RIDGE CONTINUES TO WEAKEN AS THE SHALLOW ARTIC AIR HAS MAINLY
DISSIPATED AS ITS MOVED EASTWARD. THIS HAS DELAYED THE ONSET OF
MVFR CIGS /AND ANY GRADUALLY DETERIORATING VSBYS TO IFR. THE ONSET
OF CONDITIONS HAS BEEN PUSHED BACK. THE LOWERING CONDITIONS WILL
OCCUR FROM WEST TO EAST BETWEEN 11-18Z AS DEEPENING MOISTURE /AND
THE ONSET OF LIGHT SNOW/ STREAKS EASTWARD ALONG AND AHEAD OF A
SLOWLY SWD SAGGING COLD FRONT.
WIDESPREAD IFR TO LIFR CONDITIONS ARE IN STORE FOR LATE SUNDAY
INTO EARLY MON AS HEAVIER SNOW IMPACTS THE NORTHERN HALF OF THE
STATE. THE SOUTHERN HALF WILL SEE A WINTRY MIX WORK INTO THE
SOUTHERN TAF SITES...FROM JST AND AOO...TO KMDT- KLNS AREA WITH
POTENTIAL FOR ICING. THIS IS DUE TO WARM AIR ADVECTION INTO THE
MID LEVELS...AND COLD TEMPERATURES AT THE SURFACE. LLWS POSS
SUNDAY NIGHT ACROSS THE S/SE AS LOW LEVEL JET ROTATES THROUGH.
OUTLOOK...
SUN...WIDESPREAD IFR-MVFR CIGS AND IFR VSBYS DEVELOPING DURING THE
MORNING-EARLY AFTERNOON HOURS. LLWS POSS SUN NIGHT SE.
MON...REDUCED CONDS EARLY...GRADUALLY IMPROVING AS THE STORM
MOVES AWAY FROM THE AREA. LLWS POSS MON AFT/NIGHT.
TUE...NO SIG WX.
WED...MVFR IN SHSN NW...VFR SE.
THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR PAZ004>006-
010>012-017>019-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY UNTIL 8 AM EST MONDAY FOR PAZ033>036-
064>066.
WINTER STORM WARNING UNTIL 8 AM EST MONDAY FOR PAZ024>028-056-
057-059-063.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...DEVOIR
SHORT TERM...DEVOIR
LONG TERM...RXR
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
948 AM CST SUN FEB 1 2015
.UPDATE...
SHOWERS CONTINUE ACROSS MUCH OF THE MIDSOUTH THIS MORNING. THE
SHOWERS ARE OCCURRING AHEAD OF A LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT. BACK EDGE OF SHOWERS HAVE ALREADY PUSHED
EAST OF RANDOLPH...LAWRENCE...CLAY AND GREENE COUNTIES IN
NORTHEAST ARKANSAS. MODELS INDICATE BACK EDGE WILL BE EAST OF THE
MISSISSIPPI RIVER BY NOON. WILL UPDATE TO TRIM POPS ACCORDINGLY.
STILL CAN/T RULE OUT ISOLATED SHOWERS POPPING UP WEST OF THE RIVER BUT
BULK OF RAIN WILL BE DONE WITH. THINK THE ONLY LOCATIONS WITH
CHANCES OF THUNDER WILL BE ACROSS NORTHEAST MISSISSIPPI AS PRECIP
IS MOVING EAST SO FAST.
MEANWHILE...COLD FRONT HAS JUST PUSHED INTO WESTERN ARKANSAS SO
THERE WILL BE A COUPLE OF HOURS OF NO PRECIP AND WARM AIR
ADVECTION OCCURRING ACROSS NE ARKANSAS THAT WILL NEED TO ALSO BUMP
UP HIGHS TO THE MID 50S.
KRM
&&
.DISCUSSION... /ISSUED 430 AM CST SUN FEB 1 2015/
AN ACTIVE WEATHER PATTERN CAN BE EXPECTED FOR THE FIRST WEEK OF
FEBRUARY ACROSS THE MIDSOUTH. EARLY THIS MORNING...SOUTHEAST WINDS
WERE PUSHING MILD AIR INTO THE REGION WITH TEMPERATURES IN SOME
LOCATIONS WARMER THAN THEY WERE DURING THE DAY YESTERDAY. THE
LOWER LEVELS WERE VERY DRY ACROSS MUCH OF THE AREA WITH SURFACE
DEW POINTS IN THE TEENS ALONG THE TN RIVER VALLEY. A WARM FRONT
WAS PUSHING TOWARD THE MIDSOUTH FROM THE SOUTHWEST WITH WIDESPREAD
SHOWERS...THE RAIN WAS HAVING A DIFFICULT TIME REACHING THE GROUND
IN OUR FORECAST AREA WITH THE DRY LOW LEVELS. SURFACE LOW PRESSURE
WAS DEVELOPING OVER THE CENTRAL PLAINS WITH MUCH COLDER AIR
LOCATED ACROSS THE NORTHERN PLAINS PUSHING SOUTHWARD BEHIND THE
LOW.
NOT MUCH CHANGE FROM THE EARLIER FORECAST. AS A UPPER LEVEL TROUGH
DIGS INTO THE MIDDLE MS RIVER VALLEY TODAY...THE SURFACE LOW WILL
STRENGTHEN TO NEAR 1000 MB AND BE LOCATED OVER SOUTHERN IN BY SUNSET.
A COLD FRONT TRAILING SOUTHWESTWARD FROM THE LOW WILL APPROACH
EASTERN AR BY NOON AND MOVE RAPIDLY TO NEAR THE TN RIVER AND THE MS /
AL BORDER BY SUNSET. SHOWERS WILL QUICKLY SPREAD ACROSS THE MIDSOUTH
THIS MORNING AHEAD OF THIS SYSTEM AS UPPER LIFT INCREASES
DRAMATICALLY AND THE LOWER LEVELS BECOME SATURATED. BASED ON THE
FORECAST ELEVATED INSTABILITY...ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG AND SOUTH OF INTERSTATE 40. ALSO...SOME SURFACE BASED
INSTABILITY MAY PUSH INTO NORTH MS DURING THE DAY. THE MODELS
INCLUDING THE HRRR AND RAP ARE SHOWING THE RAIN BEGINNING TO PUSH OUT
OF PORTIONS OF NORTHEAST AR AND PORTIONS OF THE MO BOOTHEEL BY EARLY
AFTERNOON...SO BEGAN TO SHOW THE POPS DECREASING FROM THE WEST AT
THIS TIME.
RAIN IS FORECAST TO QUICKLY END FROM THE WEST EARLY THIS EVENING.
LATEST MODELS ARE NOT SHOWING MUCH IF ANY PRECIP ONCE TEMPERATURES
BECOME COLD ENOUGH FOR SNOW...BUT DID CONTINUE TO MENTION A SLIGHT
CHANCE OF FLURRIES AFTER MIDNIGHT IN ASSOCIATION WITH A TRAILING
UPPER LEVEL TROUGH. OTHERWISE...STRONG AND GUSTY NORTHWEST WINDS
WILL PUSH MUCH COLDER AIR INTO THE AREA WITH WIND CHILL READINGS
DROPPING TO BETWEEN 10 AND 20 DEGREES AFTER MIDNIGHT.
MONDAY WILL BE A VERY COLD DAY AS MODIFIED ARCTIC AIR SETTLES OVER
THE MIDSOUTH. HIGHS WILL ONLY BE IN THE 30S WITH SOME LOCATIONS
NEAR THE MO AND KY BORDERS REMAINING A LITTLE BELOW FREEZING. CLOUDS
ARE EXPECTED TO BEGIN CLEARING BY AFTERNOON. MONDAY NIGHT WILL
SEE LOW TEMPERATURES DIP INTO THE LOWER AND MIDDLE 20S.
HIGH PRESSURE WILL MOVE TO ALONG THE ATLANTIC COAST BY LATE TUESDAY
WITH WINDS TURNING TO THE SOUTH ACROSS THE MIDSOUTH. THIS WILL
ALLOW TEMPERATURES TO WARM TO BETWEEN THE MIDDLE 40S AND LOWER 50S
DURING THE AFTERNOON WITH ABUNDANT SUNSHINE.
ATTENTION TURNS TO OUR THE NEXT WEATHER SYSTEM WEDNESDAY...AN
UPPER LOW OVER TX IN THE SOUTHERN STREAM. THE UPPER LOW IS
FORECAST TO BECOME AN OPEN TROUGH AS IT MOVES INTO THE WESTERN GULF.
SURFACE LOW PRESSURE WILL DEVELOP OVER THE WESTERN GULF WEDNESDAY AS
AN ARCTIC FRONT APPROACHES THE MIDSOUTH FROM THE NORTH LATE IN THE
DAY. LOOKS LIKE THE MIDSOUTH WILL BE BETWEEN THESE TWO SYSTEMS
WEDNESDAY WITH MOST RAIN BEING TO OUR SOUTH ALONG THE NORTHWEST
GULF COAST.
THE WEATHER BECOMES INTERESTING AND COMPLICATED WEDNESDAY NIGHT AND
THURSDAY...ALTHOUGH THE GFS AND ECMWF STILL ARE NOT IN GOOD
AGREEMENT. AS THE UPPER LEVEL TROUGH AND ASSOCIATED SURFACE LOW TO
OUR SOUTH MOVE EASTWARD WITH THE UPPER TROUGH WEAKENING...IT LOOKS
LIKE MOST OF THE RAIN WITH THIS SYSTEM WILL STAY TO OUR SOUTH
POSSIBLY MOVING INTO PORTIONS OF NORTH MS. MEANWHILE...MODELS SHOW
THE ARCTIC FRONT CONTINUING TO PUSH SOUTHWARD THROUGH THE MIDSOUTH.
THE GFS IS FASTER WITH THE COLDER AIR THAN THE ECMWF. SOME LIGHT RAIN
IS INDICATED WITH THIS FRONT WEDNESDAY NIGHT...CHANGING TO LIGHT
SNOW FROM THE NORTH WITH SOME SLEET OR FREEZING POSSIBLE IN THE
TRANSITION ZONE. FOR THURSDAY...THE ECMWF SHOWS THE LIGHT WINTRY
PRECIP MOVING FURTHER SOUTH AS THE ARCTIC FRONT CONTINUES SOUTH...
BUT THE ECMWF QUICKLY MOVES THE PRECIP OUT OF THE AREA BY
AFTERNOON. ON THE OTHER HAND...THE GFS SHOWS A STRONGER UPPER LEVEL
TROUGH FROM THE NORTHWEST INTERACTING WITH THE COLD AIR THURSDAY
WHICH COULD LEAD TO SOME LIGHT SNOW ACCUMULATIONS. FOR NOW...LOTS OF
UNCERTAINTY DURING THIS TIME FRAME. WILL HAVE TO SEE HOW THE MODELS
COME TOGETHER ON THIS SITUATION REGARDING PRECIP IF ANY AND PRECIP
TYPES.
JCL
&&
.AVIATION...
12Z TAF CYCLE
EXPECTING FLIGHT CATEGORIES TO DROP QUICKLY THIS MORNING AS A
BAND OF RAINFALL HAS ALREADY OVERSPREAD JBR AND MEM...MKL AND TUP
SHORTLY. LOOKING AT OBS TO THE WEST...WIDESPREAD IFR CIGS EXIST
WHICH WILL DEVELOP AT JBR AND MEM JUST AFTER 12Z SUNDAY. RAINFALL
COULD BE MODERATE AT TIMES THROUGH ABOUT 21Z AT ALL TAF SITES.
ADDED TEMPO THUNDER AT TUP WHERE SOME INSTABILITY IS FORECAST TO
DEVELOP AHEAD OF THE FRONTAL BOUNDARY. BEST WINDOW FOR THIS LOOKS
TO BE BETWEEN APPROX 20-23Z. WINDS WILL ALSO INCREASE INTO THE
10-15 KT RANGE WITH GUSTS NEAR 18-20 KTS THROUGH THE DAY FROM THE
SOUTH...GRADUALLY VEERING TO SOUTHWEST...THEN WEST-NORTHWESTERLY
BEHIND THE FRONTAL BOUNDARY. LIGHT SHOWERS WILL END FROM WEST TO
EAST SUNDAY NIGHT WITH WINDS REMAINING IN THE 10-15 KT RANGE FROM
THE NORTHWEST. CIGS WILL SLOWLY RISE THROUGH EARLY MONDAY MORNING.
TVT
&&
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
525 AM CST SUN FEB 1 2015
.UPDATE...
UPDATED FOR 12Z AVIATION DISCUSSION BELOW...
&&
.PREV DISCUSSION... /ISSUED 430 AM CST SUN FEB 1 2015/
DISCUSSION...
AN ACTIVE WEATHER PATTERN CAN BE EXPECTED FOR THE FIRST WEEK OF
FEBRUARY ACROSS THE MIDSOUTH. EARLY THIS MORNING...SOUTHEAST WINDS
WERE PUSHING MILD AIR INTO THE REGION WITH TEMPERATURES IN
SOME LOCATIONS WARMER THAN THEY WERE DURING THE DAY YESTERDAY. THE
LOWER LEVELS WERE VERY DRY ACROSS MUCH OF THE AREA WITH SURFACE DEW
POINTS IN THE TEENS ALONG THE TN RIVER VALLEY. A WARM FRONT WAS
PUSHING TOWARD THE MIDSOUTH FROM THE SOUTHWEST WITH WIDESPREAD
SHOWERS...THE RAIN WAS HAVING A DIFFICULT TIME REACHING THE GROUND
IN OUR FORECAST AREA WITH THE DRY LOW LEVELS. SURFACE LOW PRESSURE
WAS DEVELOPING OVER THE CENTRAL PLAINS WITH MUCH COLDER AIR LOCATED
ACROSS THE NORTHERN PLAINS PUSHING SOUTHWARD BEHIND THE LOW.
NOT MUCH CHANGE FROM THE EARLIER FORECAST. AS A UPPER LEVEL TROUGH
DIGS INTO THE MIDDLE MS RIVER VALLEY TODAY...THE SURFACE LOW WILL
STRENGTHEN TO NEAR 1000 MB AND BE LOCATED OVER SOUTHERN IN BY SUNSET.
A COLD FRONT TRAILING SOUTHWESTWARD FROM THE LOW WILL APPROACH
EASTERN AR BY NOON AND MOVE RAPIDLY TO NEAR THE TN RIVER AND THE MS /
AL BORDER BY SUNSET. SHOWERS WILL QUICKLY SPREAD ACROSS THE MIDSOUTH
THIS MORNING AHEAD OF THIS SYSTEM AS UPPER LIFT INCREASES
DRAMATICALLY AND THE LOWER LEVELS BECOME SATURATED. BASED ON THE
FORECAST ELEVATED INSTABILITY...ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG AND SOUTH OF INTERSTATE 40. ALSO...SOME SURFACE BASED
INSTABILITY MAY PUSH INTO NORTH MS DURING THE DAY. THE MODELS
INCLUDING THE HRRR AND RAP ARE SHOWING THE RAIN BEGINNING TO PUSH OUT
OF PORTIONS OF NORTHEAST AR AND PORTIONS OF THE MO BOOTHEEL BY EARLY
AFTERNOON...SO BEGAN TO SHOW THE POPS DECREASING FROM THE WEST AT
THIS TIME.
RAIN IS FORECAST TO QUICKLY END FROM THE WEST EARLY THIS EVENING.
LATEST MODELS ARE NOT SHOWING MUCH IF ANY PRECIP ONCE TEMPERATURES
BECOME COLD ENOUGH FOR SNOW...BUT DID CONTINUE TO MENTION A SLIGHT
CHANCE OF FLURRIES AFTER MIDNIGHT IN ASSOCIATION WITH A TRAILING
UPPER LEVEL TROUGH. OTHERWISE...STRONG AND GUSTY NORTHWEST WINDS
WILL PUSH MUCH COLDER AIR INTO THE AREA WITH WIND CHILL READINGS
DROPPING TO BETWEEN 10 AND 20 DEGREES AFTER MIDNIGHT.
MONDAY WILL BE A VERY COLD DAY AS MODIFIED ARCTIC AIR SETTLES OVER
THE MIDSOUTH. HIGHS WILL ONLY BE IN THE 30S WITH SOME LOCATIONS
NEAR THE MO AND KY BORDERS REMAINING A LITTLE BELOW FREEZING. CLOUDS
ARE EXPECTED TO BEGIN CLEARING BY AFTERNOON. MONDAY NIGHT WILL
SEE LOW TEMPERATURES DIP INTO THE LOWER AND MIDDLE 20S.
HIGH PRESSURE WILL MOVE TO ALONG THE ATLANTIC COAST BY LATE TUESDAY
WITH WINDS TURNING TO THE SOUTH ACROSS THE MIDSOUTH. THIS WILL
ALLOW TEMPERATURES TO WARM TO BETWEEN THE MIDDLE 40S AND LOWER 50S
DURING THE AFTERNOON WITH ABUNDANT SUNSHINE.
ATTENTION TURNS TO OUR THE NEXT WEATHER SYSTEM WEDNESDAY...AN
UPPER LOW OVER TX IN THE SOUTHERN STREAM. THE UPPER LOW IS
FORECAST TO BECOME AN OPEN TROUGH AS IT MOVES INTO THE WESTERN GULF.
SURFACE LOW PRESSURE WILL DEVELOP OVER THE WESTERN GULF WEDNESDAY AS
AN ARCTIC FRONT APPROACHES THE MIDSOUTH FROM THE NORTH LATE IN THE
DAY. LOOKS LIKE THE MIDSOUTH WILL BE BETWEEN THESE TWO SYSTEMS
WEDNESDAY WITH MOST RAIN BEING TO OUR SOUTH ALONG THE NORTHWEST
GULF COAST.
THE WEATHER BECOMES INTERESTING AND COMPLICATED WEDNESDAY NIGHT AND
THURSDAY...ALTHOUGH THE GFS AND ECMWF STILL ARE NOT IN GOOD
AGREEMENT. AS THE UPPER LEVEL TROUGH AND ASSOCIATED SURFACE LOW TO
OUR SOUTH MOVE EASTWARD WITH THE UPPER TROUGH WEAKENING...IT LOOKS
LIKE MOST OF THE RAIN WITH THIS SYSTEM WILL STAY TO OUR SOUTH
POSSIBLY MOVING INTO PORTIONS OF NORTH MS. MEANWHILE...MODELS SHOW
THE ARCTIC FRONT CONTINUING TO PUSH SOUTHWARD THROUGH THE MIDSOUTH.
THE GFS IS FASTER WITH THE COLDER AIR THAN THE ECMWF. SOME LIGHT RAIN
IS INDICATED WITH THIS FRONT WEDNESDAY NIGHT...CHANGING TO LIGHT
SNOW FROM THE NORTH WITH SOME SLEET OR FREEZING POSSIBLE IN THE
TRANSITION ZONE. FOR THURSDAY...THE ECMWF SHOWS THE LIGHT WINTRY
PRECIP MOVING FURTHER SOUTH AS THE ARCTIC FRONT CONTINUES SOUTH...
BUT THE ECMWF QUICKLY MOVES THE PRECIP OUT OF THE AREA BY
AFTERNOON. ON THE OTHER HAND...THE GFS SHOWS A STRONGER UPPER LEVEL
TROUGH FROM THE NORTHWEST INTERACTING WITH THE COLD AIR THURSDAY
WHICH COULD LEAD TO SOME LIGHT SNOW ACCUMULATIONS. FOR NOW...LOTS OF
UNCERTAINTY DURING THIS TIME FRAME. WILL HAVE TO SEE HOW THE MODELS
COME TOGETHER ON THIS SITUATION REGARDING PRECIP IF ANY AND PRECIP
TYPES.
JCL
AVIATION...
12Z TAF CYCLE
EXPECTING FLIGHT CATEGORIES TO DROP QUICKLY THIS MORNING AS A
BAND OF RAINFALL HAS ALREADY OVERSPREAD JBR AND MEM...MKL AND TUP
SHORTLY. LOOKING AT OBS TO THE WEST...WIDESPREAD IFR CIGS EXIST
WHICH WILL DEVELOP AT JBR AND MEM JUST AFTER 12Z SUNDAY. RAINFALL
COULD BE MODERATE AT TIMES THROUGH ABOUT 21Z AT ALL TAF SITES.
ADDED TEMPO THUNDER AT TUP WHERE SOME INSTABILITY IS FORECAST TO
DEVELOP AHEAD OF THE FRONTAL BOUNDARY. BEST WINDOW FOR THIS LOOKS
TO BE BETWEEN APPROX 20-23Z. WINDS WILL ALSO INCREASE INTO THE
10-15 KT RANGE WITH GUSTS NEAR 18-20 KTS THROUGH THE DAY FROM THE
SOUTH...GRADUALLY VEERING TO SOUTHWEST...THEN WEST-NORTHWESTERLY
BEHIND THE FRONTAL BOUNDARY. LIGHT SHOWERS WILL END FROM WEST TO
EAST SUNDAY NIGHT WITH WINDS REMAINING IN THE 10-15 KT RANGE FROM
THE NORTHWEST. CIGS WILL SLOWLY RISE THROUGH EARLY MONDAY MORNING.
TVT
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
430 AM CST SUN FEB 1 2015
.DISCUSSION...
AN ACTIVE WEATHER PATTERN CAN BE EXPECTED FOR THE FIRST WEEK OF
FEBRUARY ACROSS THE MIDSOUTH. EARLY THIS MORNING...SOUTHEAST WINDS
WERE PUSHING MILD AIR INTO THE REGION WITH TEMPERATURES IN
SOME LOCATIONS WARMER THAN THEY WERE DURING THE DAY YESTERDAY. THE
LOWER LEVELS WERE VERY DRY ACROSS MUCH OF THE AREA WITH SURFACE DEW
POINTS IN THE TEENS ALONG THE TN RIVER VALLEY. A WARM FRONT WAS
PUSHING TOWARD THE MIDSOUTH FROM THE SOUTHWEST WITH WIDESPREAD
SHOWERS...THE RAIN WAS HAVING A DIFFICULT TIME REACHING THE GROUND
IN OUR FORECAST AREA WITH THE DRY LOW LEVELS. SURFACE LOW PRESSURE
WAS DEVELOPING OVER THE CENTRAL PLAINS WITH MUCH COLDER AIR LOCATED
ACROSS THE NORTHERN PLAINS PUSHING SOUTHWARD BEHIND THE LOW.
NOT MUCH CHANGE FROM THE EARLIER FORECAST. AS A UPPER LEVEL TROUGH
DIGS INTO THE MIDDLE MS RIVER VALLEY TODAY...THE SURFACE LOW WILL
STRENGTHEN TO NEAR 1000 MB AND BE LOCATED OVER SOUTHERN IN BY SUNSET.
A COLD FRONT TRAILING SOUTHWESTWARD FROM THE LOW WILL APPROACH
EASTERN AR BY NOON AND MOVE RAPIDLY TO NEAR THE TN RIVER AND THE MS /
AL BORDER BY SUNSET. SHOWERS WILL QUICKLY SPREAD ACROSS THE MIDSOUTH
THIS MORNING AHEAD OF THIS SYSTEM AS UPPER LIFT INCREASES
DRAMATICALLY AND THE LOWER LEVELS BECOME SATURATED. BASED ON THE
FORECAST ELEVATED INSTABILITY...ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG AND SOUTH OF INTERSTATE 40. ALSO...SOME SURFACE BASED
INSTABILITY MAY PUSH INTO NORTH MS DURING THE DAY. THE MODELS
INCLUDING THE HRRR AND RAP ARE SHOWING THE RAIN BEGINNING TO PUSH OUT
OF PORTIONS OF NORTHEAST AR AND PORTIONS OF THE MO BOOTHEEL BY EARLY
AFTERNOON...SO BEGAN TO SHOW THE POPS DECREASING FROM THE WEST AT
THIS TIME.
RAIN IS FORECAST TO QUICKLY END FROM THE WEST EARLY THIS EVENING.
LATEST MODELS ARE NOT SHOWING MUCH IF ANY PRECIP ONCE TEMPERATURES
BECOME COLD ENOUGH FOR SNOW...BUT DID CONTINUE TO MENTION A SLIGHT
CHANCE OF FLURRIES AFTER MIDNIGHT IN ASSOCIATION WITH A TRAILING
UPPER LEVEL TROUGH. OTHERWISE...STRONG AND GUSTY NORTHWEST WINDS
WILL PUSH MUCH COLDER AIR INTO THE AREA WITH WIND CHILL READINGS
DROPPING TO BETWEEN 10 AND 20 DEGREES AFTER MIDNIGHT.
MONDAY WILL BE A VERY COLD DAY AS MODIFIED ARCTIC AIR SETTLES OVER
THE MIDSOUTH. HIGHS WILL ONLY BE IN THE 30S WITH SOME LOCATIONS
NEAR THE MO AND KY BORDERS REMAINING A LITTLE BELOW FREEZING. CLOUDS
ARE EXPECTED TO BEGIN CLEARING BY AFTERNOON. MONDAY NIGHT WILL
SEE LOW TEMPERATURES DIP INTO THE LOWER AND MIDDLE 20S.
HIGH PRESSURE WILL MOVE TO ALONG THE ATLANTIC COAST BY LATE TUESDAY
WITH WINDS TURNING TO THE SOUTH ACROSS THE MIDSOUTH. THIS WILL
ALLOW TEMPERATURES TO WARM TO BETWEEN THE MIDDLE 40S AND LOWER 50S
DURING THE AFTERNOON WITH ABUNDANT SUNSHINE.
ATTENTION TURNS TO OUR THE NEXT WEATHER SYSTEM WEDNESDAY...AN
UPPER LOW OVER TX IN THE SOUTHERN STREAM. THE UPPER LOW IS
FORECAST TO BECOME AN OPEN TROUGH AS IT MOVES INTO THE WESTERN GULF.
SURFACE LOW PRESSURE WILL DEVELOP OVER THE WESTERN GULF WEDNESDAY AS
AN ARCTIC FRONT APPROACHES THE MIDSOUTH FROM THE NORTH LATE IN THE
DAY. LOOKS LIKE THE MIDSOUTH WILL BE BETWEEN THESE TWO SYSTEMS
WEDNESDAY WITH MOST RAIN BEING TO OUR SOUTH ALONG THE NORTHWEST
GULF COAST.
THE WEATHER BECOMES INTERESTING AND COMPLICATED WEDNESDAY NIGHT AND
THURSDAY...ALTHOUGH THE GFS AND ECMWF STILL ARE NOT IN GOOD
AGREEMENT. AS THE UPPER LEVEL TROUGH AND ASSOCIATED SURFACE LOW TO
OUR SOUTH MOVE EASTWARD WITH THE UPPER TROUGH WEAKENING...IT LOOKS
LIKE MOST OF THE RAIN WITH THIS SYSTEM WILL STAY TO OUR SOUTH
POSSIBLY MOVING INTO PORTIONS OF NORTH MS. MEANWHILE...MODELS SHOW
THE ARCTIC FRONT CONTINUING TO PUSH SOUTHWARD THROUGH THE MIDSOUTH.
THE GFS IS FASTER WITH THE COLDER AIR THAN THE ECMWF. SOME LIGHT RAIN
IS INDICATED WITH THIS FRONT WEDNESDAY NIGHT...CHANGING TO LIGHT
SNOW FROM THE NORTH WITH SOME SLEET OR FREEZING POSSIBLE IN THE
TRANSITION ZONE. FOR THURSDAY...THE ECMWF SHOWS THE LIGHT WINTRY
PRECIP MOVING FURTHER SOUTH AS THE ARCTIC FRONT CONTINUES SOUTH...
BUT THE ECMWF QUICKLY MOVES THE PRECIP OUT OF THE AREA BY
AFTERNOON. ON THE OTHER HAND...THE GFS SHOWS A STRONGER UPPER LEVEL
TROUGH FROM THE NORTHWEST INTERACTING WITH THE COLD AIR THURSDAY
WHICH COULD LEAD TO SOME LIGHT SNOW ACCUMULATIONS. FOR NOW...LOTS OF
UNCERTAINTY DURING THIS TIME FRAME. WILL HAVE TO SEE HOW THE MODELS
COME TOGETHER ON THIS SITUATION REGARDING PRECIP IF ANY AND PRECIP
TYPES.
JCL
&&
.AVIATION...
06Z TAF CYCLE
DEFINITELY NOT GOOD CONDITIONS FOR FLYING OVER THE NEXT 24 HOURS.
CONDITIONS ARE VFR CURRENTLY AT ALL SITES...BUT DETERIORATING
CONDITIONS ARE EXPECTED TONIGHT...WITH IFR CONDITIONS PREVAILING
TOMORROW. EXPECT CIGS TO LOWER TO IFR BY MID MORNING...01/14Z-01/17Z.
LIGHT SOUTHEAST WINDS WILL VEER SOUTHERLY OVERNIGHT...INCREASE AND
BECOME GUSTY SUNDAY MORNING. SUSTAINED SPEEDS SHOULD BE 10-15KT
WITH GUSTS TO 20KTS. FURTHER VEERING IS EXPECTED TOMORROW
AFTERNOON WHEN SOUTHWEST WINDS ARE EXPECTED. VIS WILL BE MVFR FOR
MOST OF THE DAY TOMORROW DUE TO RAIN. ALTHOUGH THUNDERSTORMS
CANNOT BE RULED OUT...DO NOT FEEL THEY WILL BE NUMEROUS TO INCLUDE
IN TAFS AT THIS TIME. SOME IMPROVEMENT TO CIGS IS POSSIBLE LATE
TOMORROW...NEAR AND AFTER 00Z. HOWEVER GUIDANCE TYPICALLY CLEARS
LOW CLOUDS OUT TOO QUICKLY SO WILL HOLD ONTO LOW CLOUDS THROUGH
THE TAF CYCLE. RAIN SHOULD COME TO AN END FOR JBR BEFORE
00Z...AROUND 00Z AT MEM...AND A COUPLE OF HOURS LATER AT MKL.
WILL KEEP PREVAILING RAIN AT TUP THROUGH 06Z.
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS EL PASO TX/SANTA TERESA NM
357 AM MST SUN FEB 1 2015
.SYNOPSIS...
UPPER LOW OVER THE CENTRAL BAJA PENINSULA WHICH BROUGHT THE LOWLAND
RAIN AND MOUNTAIN SNOW ON SATURDAY...CONTINUES TO DRIFT SOUTHEAST
AND TAKE ANY REMAINING MOISTURE WITH IT. AN UPPER RIDGE WILL BEGIN
BUILDING OVER THE DESERT SOUTHWEST OVER THE NEXT SEVERAL DAYS. THIS
WILL KEEP THE SKIES MOSTLY CLEAR FOR MUCH OF THE UPCOMING WEEK.
TEMPERATURES TODAY WILL STILL BE A BIT BELOW NORMAL BEFORE WARMING
BACK TO NORMAL MONDAY. TUESDAY AND BEYOND...TEMPERATURES WILL
CONTINUE TO WARM MUCH ABOVE NORMAL.
&&
.DISCUSSION...
WINTER STORM SYSTEM ABOUT OVER. DOUBLE LOW FROM YESTERDAY HAS
DEVOLVED INTO SINGLE LOW OVER THE CENTRAL BAJA AS NORTHERN LOW FROM
SATURDAY FILLED IN OVER NORTHERN ARIZONA. IN CONCERT WITH AN UPPER
TROUGH DROPPING DOWN FROM THE NORTH NOW OVER CENTRAL NEW MEXICO...
REMAINING MOISTURE WILL SHEAR OUT TO THE EAST OF THE CWA. WOULDN`T
RULE OUT A FEW SPRINKLES YET THIS MORNING BUT LEFT POPS OUT OF THE
ZONES OTHER THAN EARLY THIS MORNING OVER THE BOOTHEEL...CLOSEST TO
THE UPPER LOW. DENSE FOG WAS A CONCERN AS LOW DEWPOINT DEPRESSIONS
DEVELOPED MOST AREAS WITH THE WET GROUND. HRRR ALSO SHOWED THE LOW
DEPRESSIONS BECOMING WIDESPREAD AFTER 11Z...BUT IN THE END FIGURED
WITH CLOUDS STICKING AROUND THROUGH THE MORNING HOURS WOULD JUST
MENTION FOG IN THE ZONES/GRIDS. ONE OTHER NOTE...MODERATE RAINFALL
OVER THE GILA REGION ON SATURDAY PRODUCED DECENT RISES IN THE GILA
RIVER. THE GILA RIVER AT VIRDEN ACTUALLY BRIEFLY TOPPED ACTION STAGE
BUT IS FORECAST TO QUICKLY DROP TODAY. ALL OTHER GILA RIVER GAGES
REMAINED BELOW ACTION STAGE.
OTHERWISE UPPER RIDGE WILL BUILD IN OVER THE DESERT SOUTHWEST TODAY
AND MONDAY. THIS SHOULD KEEP LOWER CLOUDS OUT ALTHOUGH SOME PATCHES
OF HIGHER CLOUDS WILL PUSH THROUGH...ESPECIALLY WITH OLD WEAKENED
PACIFIC FRONT ALOFT ON WEDNESDAY AND AGAIN ON FRIDAY. WEAK BACK DOOR
COLD FRONT MOVES IN ON THURSDAY AS UPPER TROUGH RUNS DOWN THE FRONT
SIDE OF THE RIDGE. NOT MUCH COLD ADVECTION WITH THIS BUT ENOUGH TO
STUNT THE WARMING FOR A DAY. TEMPERATURES WILL CLIMB TO NEAR NORMAL
MONDAY AND THEN TO MUCH ABOVE NORMAL THE REST OF THE WEEK. BY NEXT
SATURDAY AND SUNDAY LOWLAND TEMPS COULD TOP 70 DEGREES.
&&
.AVIATION...VALID 01/12Z-02/12Z...
CONDITIONS MOSTLY VFR NOW WITH SCT/BKN100 WITH FEW LAYERS TO 250.
EXPECT PATCHY IFR FOG TO DEVELOP AT THIS TIME...WITH VISIBILITIES OF
ONE-QUARTER TO ONE MILE. CONDITIONS DISSIPATING AFTER 17Z. CLOUDS
DECREASING AFTER 20Z.
&&
.FIRE WEATHER...
UPPER LOW NOW WELL SOUTH OF THE AREA AND TAKING MOST OF THE CLOUDS
OFF TO OUR EAST THIS MORNING. SOME PATCHY FOG MAY DEVELOP THROUGH
MID MORNING. MIN RH`S TODAY WILL BE IN THE 50S AND DECREASING TO THE
40S BY TUESDAY. OTHERWISE THE NEXT 5 TO 7 DAYS LOOKS VERY
UNEVENTFUL...WITH VERY FEW CLOUDS AND TEMPERATURES WARMING BACK TO
ABOVE NORMAL BY MONDAY AND BEYOND. BY THE END OF THE WEEK HIGH TEMPS
COULD BE AROUND 10 DEGREES ABOVE NORMAL.
&&
.PRELIMINARY POINT TEMPS/POPS...
EL PASO 57 34 61 37 65 / 0 0 0 0 0
SIERRA BLANCA 55 31 59 35 63 / 0 0 0 0 0
LAS CRUCES 56 32 59 35 64 / 0 0 0 0 0
ALAMOGORDO 56 30 57 33 62 / 0 0 0 0 0
CLOUDCROFT 40 22 45 27 48 / 0 0 0 0 0
TRUTH OR CONSEQUENCES 54 33 58 34 62 / 0 0 0 0 0
SILVER CITY 51 31 54 33 60 / 0 0 0 0 0
DEMING 57 31 60 33 64 / 0 0 0 0 0
LORDSBURG 57 30 60 33 63 / 10 0 0 0 0
WEST EL PASO METRO 59 35 61 39 65 / 0 0 0 0 0
DELL CITY 55 29 60 32 64 / 0 0 0 0 0
FORT HANCOCK 56 35 61 37 64 / 0 0 0 0 0
LOMA LINDA 52 31 55 35 59 / 0 0 0 0 0
FABENS 57 33 60 35 64 / 0 0 0 0 0
SANTA TERESA 57 32 60 35 64 / 0 0 0 0 0
WHITE SANDS HQ 57 34 59 35 63 / 0 0 0 0 0
JORNADA RANGE 56 29 58 32 63 / 0 0 0 0 0
HATCH 59 32 62 33 65 / 0 0 0 0 0
COLUMBUS 58 35 60 36 63 / 0 0 0 0 0
OROGRANDE 56 32 59 35 63 / 0 0 0 0 0
MAYHILL 45 26 52 33 58 / 0 0 0 0 0
MESCALERO 46 24 48 28 53 / 0 0 0 0 0
TIMBERON 47 27 50 33 55 / 0 0 0 0 0
WINSTON 49 29 54 32 57 / 0 0 0 0 0
HILLSBORO 52 33 55 35 60 / 0 0 0 0 0
SPACEPORT 56 31 59 34 64 / 0 0 0 0 0
LAKE ROBERTS 51 29 54 31 58 / 0 0 0 0 0
HURLEY 53 31 55 31 60 / 0 0 0 0 0
CLIFF 55 25 57 22 63 / 0 0 0 0 0
MULE CREEK 52 22 56 19 60 / 0 0 0 0 0
FAYWOOD 53 33 55 34 60 / 0 0 0 0 0
ANIMAS 58 30 62 33 65 / 10 0 0 0 0
HACHITA 58 31 61 32 66 / 0 0 0 0 0
ANTELOPE WELLS 58 30 62 31 66 / 0 0 0 0 0
CLOVERDALE 54 32 60 33 63 / 10 0 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
17/99
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1115 AM MST SUN FEB 1 2015
.UPDATE...UPDATED AVIATION DISCUSSION...
&&
.SYNOPSIS...
IN THE WAKE OF AN EXITING LOW PRESSURE SYSTEM...AREAS OF FOG...
POTENTIALLY DENSE ACROSS THE SOUTH CENTRAL DESERTS...WILL BE
POSSIBLE THROUGH THE MORNING HOURS DUE TO ABUNDANT MOISTURE AND
CLEARING SKIES. HIGH PRESSURE WILL QUICKLY COVER THE AREA TODAY
BRINGING CLEARING SKIES...DRY WEATHER...AND WARMER TEMPERATURES. THE
DRY CONDITIONS WILL PERSIST THROUGH THE WEEK WHILE A WARMING TREND
ALLOWS FOR HIGHS TO REACH NEAR 80 DEGREES ACROSS THE LOWER DESERTS
BY THE END OF THE WORK WEEK.
&&
.DISCUSSION...
AFTER A RATHER WET COUPLE OF DAYS...WHICH HAS LEFT THE BOUNDARY
LAYER AND SOILS QUITE MOIST OVER SOUTH-CENTRAL AND SOUTHWEST
AZ...CLEAR SKIES EARLY THIS MORNING HAS ALLOWED DENSE FOG TO DEVELOP
OVER THE REGION. ALTHOUGH CLEAR SKIES ABOVE THIS FOG WILL ALLOW FOR
MAXIMUM SOLAR HEATING TODAY...IT APPEARS THAT BURN-OFF WILL TAKE
SOME TIME...WITH THE LATEST HRRR NOT SHOWING FULL CLEARING UNTIL
AROUND NOON...LIKELY DUE TO THE FACT THAT THE FOG LAYERS ARE RATHER
DEEP...WITH AIRCRAFT REPORTS INDICATING TOPS OF 700-1000FT AGL. ONCE
THE FOG DOES CLEAR...STILL EXPECTING MOSTLY CLEAR SKIES FOR THE REST
OF THE DAY AS HIGH PRESSURE CONTINUES TO BUILD OVER THE REGION.
OTHER THEN EXTENDING THE DENSE FOG ADVISORY UNTIL NOON AND MAKING
MINOR ADJUSTMENTS TO THE HOURLY TEMP AND DEWPOINT GRIDS...CURRENT
INHERITED FORECASTS STILL LOOK GOOD...NO FURTHER UPDATES ARE PLANNED
AT THIS TIME.
&&
.PREVIOUS DISCUSSION...
UPPER LOW THAT BROUGHT WIDESPREAD PRECIPITATION TO THE CENTRAL
DESERTS DURING THE PAST COUPLE OF DAYS HAS FINALLY SHIFTED OFF TO
THE SOUTHEAST...ALLOWING A SUBSIDENT NELY FLOW ALOFT TO OVERSPREAD
THE AREA. STRONG SUBSIDENCE ALOFT HAS BROUGHT CONSIDERABLE CLEARING
TO SOUTH CENTRAL AZ...AND IR IMAGERY AT 2 AM SHOWED GENLY CLEAR
SKIES FROM PHOENIX WESTWARD. A FEW MID/HIGH CLOUDS PERSISTED WELL TO
THE SOUTH AND EAST OF CENTRAL PHOENIX. ALTHOUGH MOISTURE HAS STARTED
TO THIN A BIT AS SEEN BY THE LATEST SOUNDINGS WHICH SHOWED PWAT
VALUES OF 0.86 AT SAN DIEGO AND 0.74 INCHES AT TUS...BOUNDARY LAYER
MOISTURE REMAINED HIGH AFTER ALL OF THE RAIN THAT HAS RECENTLY
FALLEN. SURFACE DEWPOINTS OVER THE DESERTS WERE RUNNING MOSTLY IN
THE UPPER 40S TO AROUND 50 AND RH VALUES WERE 100 PERCENT OR CLOSE
TO IT ACROSS MUCH OF THE CENTRAL DESERTS. OBSERVED AND FORECAST
SOUNDINGS FOR THIS MORNING SHOWED A VERY FAVORABLE DENSE FOG PROFILE
AND SPOTTER REPORTS AS WELL AS WEBCAMS HAVE BEEN INDICATING DENSE
FOG FORMING ACROSS THE SOUTHEAST VALLEY AND ACROSS NW PINAL COUNTY.
AS SUCH A DENSE FOG ADVISORY HAS BEEN ISSUED FOR NWRN/NCNTRL PINAL
COUNTY AS WELL AS THE GREATER PHOENIX AREA THRU 10 AM THIS MORNING.
WE MAY HAVE TO EXPAND THE ADVISORY INTO WESTERN MARICOPA COUNTY
SHOULD FOG DEVELOP OR SPREAD WESTWARD INTO THAT AREA. OTHERWISE...
EXPECT FOG TO DISSIPATE LATER THIS MORNING LEAVING MOSTLY SUNNY
SKIES ACROSS THE CENTRAL DESERTS. UNDER MOSTLY SUNNY SKIES...HIGH
TEMPS WILL BE ABLE TO CLIMB A HANDFUL OF DEGREES AND APPROACH
SEASONAL NORMALS.
MODEL GUIDANCE REMAINS VERY CONSISTENT IN CALLING FOR DRY AND WARMER
CONDITIONS FOR THE ENTIRE WEEK...AS A STRONG UPPER LEVEL HIGH
PRESSURE RIDGE STEADILY BUILDS INTO THE DESERT SOUTHWEST. AS THE
RIDGE BUILDS...THERE WILL BE PERIODS OF HIGH CLOUDS SPREADING
THROUGH THE RIDGE AND ACROSS THE DESERTS...BUT OVERALL WE SHOULD SEE
MOSTLY SUNNY DAYS AND MOSTLY CLEAR NIGHTS. HIGH TEMPS ARE FORECAST
TO CLIMB INTO THE MID TO UPPER 70S BY TUESDAY...THEN RISE FURTHER
AND INTO THE UPPER 70S TO LOW 80S ACROSS THE WARMER DESERTS BY
FRIDAY. H5 HEIGHTS ARE FORECAST TO RISE IN EXCESS OF 585DM OVER THE
SOUTHWEST AZ AND SERN CA DESERTS BY THIS WEEKEND AND WE COULD SEE
HIGH TEMPS REACH INTO THE MID TO UPPER 80S ACROSS THE WARMER LOWER
DESERTS AS A RESULT. WE HAVE RAISED OUR FORECAST HIGH TEMPS 2-3
DEGREES FOR THE LATTER PORTION OF THE WEEK AS A RESULT OF INCREASED
CONFIDENCE IN THE VERY WARM FORECAST CONDITIONS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...
FOG IS QUICKLY BURNING OFF AND EXPECTING IMPROVING VSBYS AND VFR
CONDITIONS BY 19-20Z. EXPECTING TO SEE SOME AFTERNOON CU DEVELOPMENT
AFTER 21Z...BUT COVERAGE SHOULD REMAIN FEW TO SCATTERED WITH BASES
AROUND 5-6K FEET. FOR WINDS...LIGHT DIURNALLY DRIVEN AT ALL SITES
WITH VERY LIGHT EAST WINDS EXPECTED MONDAY MORNING. THERE IS THE
POTENTIAL FOR ANOTHER ROUND OF FOG LATE SUNDAY NIGHT INTO MONDAY
MORNING...BUT NOT ANTICIPATING ANY DENSE FOG THIS TIME AND
CONFIDENCE IN OCCURRENCE IS STILL LOW. BEST TIME FRAME FOR ANY VSBY
IMPACTS AT TERMINALS WOULD BE BETWEEN 11Z-16Z.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NO AVIATION IMPACTS FOR SOUTHEAST CALIFORNIA AS SKIES WILL REMAIN
CLEAR THROUGH MONDAY MORNING. SFC WINDS WILL RETAIN A LIGHT
NORTHERLY COMPONENT...THOUGH WILL BECOME VARIABLE AT TIMES AS THE
UNDER A WEAK PRESSURE GRADIENT.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
WARMER TEMPERATURES ARE EXPECTED ACROSS THE REGION THIS WEEK ALONG
WITH DRIER AIR. DESPITE THIS...AFTERNOON HUMIDITIES WILL ONLY DROP
INTO THE 15-25 PERCENT RANGE EACH AFTERNOON WITH GOOD OVERNIGHT
RECOVERIES EXPECTED. NO MAJOR WIND EVENTS ARE ANTICIPATED WITH WINDS
FOLLOWING THE TYPICAL DIURNAL PATTERNS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...DENSE FOG ADVISORY UNTIL NOON TODAY FOR AZZ021>023-025>028.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA/CB
AVIATION...KUHLMAN
FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
252 PM EST Sun Feb 1 2015
.Near Term [Through Today]...
Rain continues to spread into the western part of our area,
roughly on schedule with the consensus of high-resolution models.
As such, there are no substantial changes from the forecast edits
that were made this morning. The best rain chances should spread
east to the Apalachicola, to Tallahassee, to Tifton corridor in
the mid-to-late evening hours before exiting the eastern part of
our area later in the overnight or early Monday morning. There is
some marginal instability on the latest objective RAP analysis,
but it is mainly focused to the west of our area as of 19Z. This
should spread into the area overnight, so there will still be a
slight chance of a thunderstorm or two tonight. The WAA pattern in
advance of the surface cold front should hold temperatures
relatively steady in the low 60s overnight before beginning to
fall in the few hours before sunrise as the cold front arrives.
.Short Term [Tonight Through Tuesday]...
Cold front will be situated across the eastern half of the
forecast area by sunrise Monday morning, with showers ongoing
along and ahead of the boundary. The rain will end during the
morning, with skies clearing from west to east during the day.
Temperatures will vary widely across the area to start the day,
with mid 40s in the northwest and mid 60s in the southeast.
Temperatures will generally fall or remain steady through most of
the day as strong cold air advection kicks in behind the front.
Afternoon temperatures will range from the mid 40s in the
northwest to the mid 50s in the southeast.
Seasonably cool conditions are expected Monday night and Tuesday,
with lows near freezing and highs in the mid 50s to lower 60s.
Temperatures will moderate Tuesday night ahead of the next system.
At this time, it appears the rain will hold off until daylight on
Wednesday.
.Long Term [Tuesday Night Through Sunday]...
An upper low ejecting from the desert southwest will induce
cyclogenesis over the western Gulf early Wednesday morning. While
the upper low will deamplify as it is absorbed by a developing
large scale trough, the surface low will continue to move east
along the northern Gulf Coast through the day on Wednesday into
Thursday. Lift ahead of the upper trough as well as isentropic
lift in the lower levels will produce a broad area of rain across
the area from early Wednesday to early Thursday.
A cooler and drier airmass will move into the region late on
Thursday as the storm system exits. This will keep the weather
dry and slightly cooler than normal from Friday through the
weekend.
&&
.Aviation...
[Through 18Z Monday] We should see MVFR CIGS gradually develop
and spread east through the rest of the afternoon and early
evening, affecting all terminals as rain begins to move into the
area. S-SE winds may be gusty at times prior to 00Z. As some of
the steadier rain comes to an end overnight from west to east,
some IFR CIGS may develop before a cold front arrives to scour
them out around sunrise. Northwest winds behind the front tomorrow
may be gusty to between 20-30 knots as CIGS quickly improve to
VFR.
&&
.Marine...
Small Craft Advisory conditions will continue through Monday ahead
of (and behind) the approaching cold front. Winds will shift from
southwest to northwest as the front passes. Following a brief lull
early on Tuesday, easterly winds will return to exercise caution
levels and continue into Thursday. Strong offshore flow will be
possible again by Friday in the wake of another front.
&&
.Fire Weather...
A wetting rain is expected today into tonight for the entire
region. Red Flag conditions are not expected for the next week.
&&
.Hydrology...
The first system for this afternoon through Monday morning is
expected to produce mainly less than 1" of rain across the area,
although a couple of isolated amounts heavier than 1" are possible
across portions of southeast Alabama and the Florida panhandle.
The second system during the Wednesday-Thursday time frame is
expected to produce a bit more rainfall with a general 1-2"
possible. When combined with the rains from the first system and
already above average stream flows, a few rivers may approach minor
flood stage late in the week. At this time, the progressive nature
of the pattern is expected to keep rainfall amounts from getting
high enough to produce more significant flooding.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 58 64 32 58 40 / 80 50 0 0 10
Panama City 54 62 34 55 44 / 80 30 0 0 10
Dothan 48 50 30 55 39 / 80 20 0 0 10
Albany 52 58 29 55 36 / 80 40 0 0 10
Valdosta 58 63 32 58 41 / 80 60 0 0 10
Cross City 60 67 30 62 43 / 70 60 0 0 10
Apalachicola 59 65 36 56 46 / 70 40 0 0 10
&&
.TAE Watches/Warnings/Advisories...
FL...RIP CURRENT RISK through Monday evening for Coastal Bay-Coastal
Franklin-Coastal Gulf-South Walton.
GA...None.
AL...None.
GM...Small Craft Advisory until 10 PM EST Monday for Coastal waters
From Ochlockonee River to Apalachicola FL out to 20 NM-
Coastal waters from Apalachicola to Destin FL out 20 NM-
Waters from Suwannee River to Apalachicola FL from 20 to 60
NM-Waters from Apalachicola to Destin FL from 20 to 60 NM.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...CAMP
LONG TERM...CAMP
AVIATION...LAMERS
MARINE...CAMP
FIRE WEATHER...MCDERMOTT
HYDROLOGY...DVD
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
200 PM CST SUN FEB 1 2015
.UPDATE...
WE HAVE INCREASED SNOWFALL AMOUNTS SOME THIS AFTERNOON...ESPECIALLY
ACROSS NORTHERN ILLINOIS AND FAR NORTHWESTERN INDIANA. A VERY
IMPRESSIVE SYSTEM CONTINUES TO DEVELOP ACROSS THE CENTRAL CONUS THIS
MORNING IN RESPONSE TO A STRONG PV ANOMALY OVER THE CENTRAL PLAINS.
AS THIS STORM CONTINUES TO INTENSIFY THIS AFTERNOON...MODEL GUIDANCE
SUGGESTS THAT A BAND OF STRONG FRONTOGENESIS WILL DEVELOP IN AN
EMERGING DEFORMATION ZONE ASSOCIATED WITH THE 700 MB LOW...RIGHT
ACROSS NORTHERN ILLINOIS. THIS ALSO LOOKS TO OCCUR DURING THE
PERIOD OF BEST STRONG MID/UPPER LEVEL Q-VECTOR DIVERGENCE
ASSOCIATED WITH THE MID/UPPER LEVEL SYSTEM. ALL IN ALL THIS POINTS
TO STRONG DYANAMICS SUPPORTIVE OF PERIODS OF HEAVY SNOW THROUGH
THE DAY TODAY...AND LINGERING THIS EVENING. IT APPEARS THE
HEAVIEST AMOUNTS WILL EXCEED A FOOT IN MANY AREAS...WITH A FOOT
AND A HALF NOT OUT OF THE QUESTION FOR NORTHERN ILLINOIS.
THE OTHER CONCERN IS BLIZZARD CONDITIONS...WE ARE UPGRADING THE REST
OF NORTH CENTRAL ILLINOIS TO A BLIZZARD WARNING. NORTHEASTERLY
WINDS WILL ONLY INCREASE THROUGH THE AFTERNOON...WITH GUSTS
POTENTIAL UP AROUND 40 KT AT TIMES GIVEN THE STRONG GRADIENT SETTING
UP ON THE BACK SIDE OF THIS SYSTEM. THIS HAS ME SERIOUSLY CONCERNED
THAT AS THE SNOW CONTINUES TO BECOME MORE POWDERY THROUGH THE
DAY...THAT WHITE OUT CONDITIONS WILL BE OBSERVED ACROSS NORTHERN
ILLINOIS. THE OTHER CONCERN IS FOR DOWNED TREE BRANCHES AND POWER
LINES. THE SNOW THAT HAS FALLEN THUS FAR ACROSS THE AREA HAS BEEN A
STICKY WET SNOW AND HAS PRODUCED SIGNIFICANT ACCUMULATIONS ON TREES
AND POWER LINES. THE INCREASING WINDS COULD BRING DOWN POWER
LINES...LEADING TO SOME ISOLATED POWER OUTAGES.
NEW UPDATES SHOULD BE OUT SHORTLY.
KJB
&&
.SHORT TERM...
347 AM CST
THROUGH MONDAY...
HAVE BEEN SWAMPED THIS MORNING AND AM RUNNING BEHIND...SO GOING TO
KEEP DISCUSSION BRIEF THIS MORNING AND JUST HIT THE IMPORTANT
CHANGES. THE BIGGEST CHANGES TO GOING FORECAST IS THE UPGRADE TO
A BLIZZARD WARNING FOR PORTIONS OF NE IL/CHICAGO METRO AND TO
LOWER SNOW AMOUNTS AND ADD MIXED PRECIP BACK INTO GRIDS FAR SE
CWA.
GUIDANCE HAS CONTINUED TO TREND NORTH AND STRONGER WITH THE TRACK OF
THIS SYSTEM AND COMPARING GUIDANCE WITH SFC OBS AND BEST SFC
PRESSURE FALLS IT WOULD SEEM TO SUPPORT THE FARTHER NORTH TRACK THAT
THE RAP IN PARTICULAR HAS LATCHED ONTO. THE SOMEWHAT DEEPER LOW
ALONG WITH THE VERY STRONG ARCTIC HIGH SPREADING SOUTHEAST WILL
RESULT IN VERY STRONG WINDS DEVELOPING THIS AFTERNOON. INCREASING
LOW LEVEL COLD AIR ADVECTION AND SFC HEIGHT RISES FAVOR PRETTY GOOD
MIXING IN THE BOUNDARY LAYER...WHICH IS WHAT ALL MODEL FORECAST
SOUNDINGS ARE ADVERTISING. TAKING EVEN THE BEST CASE SCENARIO AND
ONE OF THE WEAKEST MODELS BUFKIT MOMENTUM TRANSFER VALUES SUPPORT
4-7 HOURS OF WIND GUSTS BETWEEN 35-40 MPH LATER THIS AFTERNOON AND
EVENING...WITH MORE AGGRESSIVE GFS/RAP SUPPORTING EVEN STRONGER
WINDS OVER A LONGER DURATION. SNOW HAS BEEN WET THUS FAR BUT WITH
TIME SHOULD SEE THE TRANSITION TOWARD DRIER/MORE BLOWABLE SNOW THIS
AFTERNOON FROM NORTH TO SOUTH AS THE COLUMN COOLS AND THE SNOW
LIQUID CONTENT DECREASES. BIGGEST UNCERTAINTY REVOLVES AROUND
REGARDING UPGRADE TO BLIZZARD WARNING WAS THE SNOW LIQUID CONTENT
AND PROBABILITY AND CONFIDENCE IS CERTAINLY HIGHER THE FARTHER NORTH
FROM I-80 THAT YOU GET...BUT EVEN AS FAR SOUTH AS I-80 FELT FAIRLY
CONFIDENT THAT WHITE OUT CONDITIONS COULD DEVELOP LATE THIS
AFTERNOON AND ESPECIALLY THIS EVENING. FARTHER WEST ACROSS NORTH
CENTRAL ILLINOIS FEEL THAT A BLIZZARD WARNING COULD EASILY BE
JUSTIFIED...BUT IN COORDINATION WITH MKX/DVN HAVE OPTED TO HOLD OFF
FOR NOW AS SNOW INTENSITY COULD BE DECREASING AS WINDS PICK UP.
QUITE POSSIBLE DAY SHIFT MAY NEED TO RE-ACCESS THIS AND AN UPGRADE
TO BLIZZARD WARNING FOR RFD AND POINTS WEST COULD OCCUR ON THE DAY
SHIFT.
OTHER BIG CHANGE TO FORECAST WAS TO ADD SLEET AND THEN DRIZZLE TO
THE FAR SOUTHEAST CWA. SFC TEMPS HAVE BEEN A BIT WARMER AND THE
FARTHER NORTH TRACK OF THE SFC LOW SHOULD KEEP LOW LEVEL WAA GOING
INTO EARLY AFTERNOON WITH AT LEAST THE THREAT OF MIXED
PRECIP...POSSIBLY TRANSITIONING OVER TO JUST DRIZZLE/SNIZZLE AS MID
LEVEL DRY SLOT OVERSPREADS THAT AREA REMOVING ICE NUCLEI FROM THE
CLOUDS LATE THIS AFTERNOON INTO THIS EVENING. THE WETTER SNOW SOUTH
OF I-80 SHOULD RESULT IN LESS SEVERE AND LESS IMPACTFUL
BLOWING/DRIFTING SNOW. GIVEN THE MARGINAL TEMPS AND POTENTIAL MIX
PRECIP HAVE CUT BACK ON ACCUMS IN THE FAR SOUTHEAST COUNTIES OF THE
CWA.
ACCUMULATING LAKE EFFECT POTENTIAL ACTUALLY LOOKS SOMEWHAT LESS
IMPRESSIVE THAN IT DID LAST NIGHT...AND IT WAS ALREADY LOOKING
MARGINAL. SOME SYSTEM SNOWS SHOULD LINGER INTO THIS EVENING BUT LAKE
CONTRIBUTIONS LOOK MINOR WITH LOW INVERSION HEIGHTS AND DECREASING
BOUNDARY LAYER RH AS THE THERMODYNAMICS IMPROVE EVER SO SLIGHTLY.
ANY LAKE ENHANCEMENT TO SNOW TOTALS SHOULD END UP BEING TRIVIAL.
FINALLY...GOING SNOWFALL TOTALS LOOK RIGHT ON TARGET AND MADE VERY
FEW CHANGES OTHER THAN IN SE AS NOTED ABOVE. A RESPECTABLY LARGE
SWATH OF A FOOT OR MORE OF SNOW STILL LOOKS LIKELY AND PROBABLY
CENTERED RELATIVELY CLOSE TO THE I-80 TO I-88/290 CORRIDORS.
ACTUALLY THINKING THAT MAX SNOWFALL TOTALS IN THE CWA COULD END UP
BEING ON THE HIGH END OF THE 10-14 INCH RANGE WITH LOCALIZED TOTALS
POTENTIALLY PUSHING A FOOT AND A HALF IF THE DEFO BAND IS INDEED AS
IMPRESSIVE AS SOME OF THE GUIDANCE WOULD SUGGEST. WHILE SNOWFALL
TOTALS WILL BE VERY IMPRESSIVE OVER MOST OF THE CWA...IT IS
IMPORTANT TO REMEMBER THE BLIZZARD WARNING IS ISSUED NOT FOR
SNOWFALL AMOUNTS BUT RATHER FOR VISIBILITY AND WINDS. THE CRITERIA
FOR BLIZZARD WARNING IS 3+ HOURS OF LESS THAN 1/4SM VSBY IN FALLING
AND/OR BLOWING SNOW ALONG WITH SUSTAINED WINDS OR FREQUENT GUSTS
OVER 35 MPH.
IZZI
&&
.LONG TERM...
118 PM CST
MONDAY THROUGH MONDAY NIGHT...
LOW PRESSURE WILL CONTINUE TO DEPART THE REGION TO THE EAST...WITH
ANTI-CYCLONIC FLOW REPLACING IT OVER THE FORECAST AREA FOR MON.
LONGWAVE FLOW PATTERN CONTINUES TO BE IN A SOMEWHAT NORTHWEST
ORIENTATION. THIS COUPLED WITH THE SFC RIDGE CENTER POSITIONED
JUST SOUTH OF THE CWFA WILL KEEP WINDS GENERALLY FROM THE
WEST/NORTHWEST. ENOUGH DRY AIR SHUD MIX DOWN TO THE SFC AND ERODE
THE BULK OF THE CLOUDS...HOWEVER NOT TOO CONFIDENT THAT CLEAR
SKIES WILL LINGER VERY LONG. THE FLOW WILL REMAIN PROGRESSIVE AND
HELP TO PUSH THE SFC RIDGE EAST/SOUTHEAST OF THE AREA BY LATE MON
NGT.
THIS WILL SETUP A WEAK MID-LVL WAVE SLIDING SOUTHEAST ACROSS THE
NORTHERN PLAINS TO ARRIVE LATE MON NGT IN THE FAR WESTERN CWFA. LLVL
FLOW WILL TURN SOUTHWESTERLY AND COULD KEEP SOME DRY AIR LOCKED IN
LONG ENOUGH TO KEEP ANY PRECIP WEST OF THE FORECAST AREA UNTIL LATE
MON NGT.
HIGHS MON WILL STRUGGLE TO WARM DESPITE THE THINNING SOLAR
SHIELDING...WITH TEMPS GENERALLY IN THE LOW/MID TEENS. THEN MON NGT
TEMPS ALOFT WILL EASILY RADIATE WITH LGT WINDS AND THIN CLOUD COVER.
FRESH SNOW PACK WILL LIKELY HELP TEMPS TO COOL INTO THE SINGLE
DIGITS ABOVE ZERO. WITH CLOUDS RETURNING LATE MON NGT FROM A WEAK
MID-LVL SYSTEM...TEMPS COULD RISE A DEGREE OR TWO AFTER
MIDNIGHT/EARLY TUE.
CURRENT EXPECTATION IS THAT ANY ACCUMULATIONS MON NGT WOULD BE LESS
THAN ONE HALF INCH.
TUESDAY THROUGH WEDNESDAY...
WITH A MID-LVL WAVE PIVOTING EAST OVERHEAD TUE MORNING...LLVL FLOW
WILL REMAIN SOUTHWESTERLY WITH SOME WEAK WARM AIR ADVECTING INTO THE
FORECAST AREA. TEMPS SHUD WARM INTO THE 20S TUE...AND WITH A GOOD
PUSH OF WARM AIR ADVECTION IN THE SOUTHERN TIER OF COUNTIES...TEMPS
COULD TAG 30 DEGREES TUE AFTN.
500MB TROUGH AXIS IS PROGGED TO SEND YET ANOTHER MID-LVL WAVE DIVING
SOUTHEAST ACROSS THE NORTHERN PLAINS TUE MORNING. GUIDANCE HAS
CONTINUED TO PROG THE ARRIVAL OF THIS FEATURE INTO THE CWFA TUE NGT.
FORCING APPEARS TO BE RATHER WEAK...HOWEVER ENOUGH MOISTURE AND LIFT
COULD EASILY PRODUCE SOME LGT SNOW ONCE AGAIN LATE TUE NGT. AT THIS
TIME IT WOULD APPEAR AROUND 1 INCH OF SNOW.
CONSIDERABLE CLOUDINESS TUE NGT WILL HELP TO HOLD TEMPS UP...WITH
OVERNIGHT LOWS IN THE UPR TEENS TO MID 20S.
SOME LINGERING LGT SNOW WED MORNING...WITH FLOW STARTING TO FLATTEN
BY MIDDAY WED. AS THE LOW LIFTS NORTHEAST WED MORNING ACROSS LOWER
MI...A TRAILING BOUNDARY WILL SLOWLY SAG SOUTH ACROSS THE WESTERN
GREAT LAKES AND MID-MISSOURI VALLEY. A WEAK WAVE WILL TRY TO DEVELOP
OVER THE CENTRAL PLAINS EARLY WED...AND COULD BRING ADDTL LGT PRECIP
BACK INTO THE FAR WEST/SOUTHWEST CWFA LATE WED AFTN.
WEDNESDAY NIGHT THROUGH SATURDAY...
ENSEMBLES CONTINUE THE THEME OF AN ACTIVE FLOW...WITH TROUGHING
GENERALLY OVER THE GREAT LAKES REGION AND RIDGING REMAINING OVER
WESTERN CANADA. THERE IS SOME WEAK FLATTENING IN THE LONGWAVE
PATTERN THUR...BUT THIS APPEARS TO BE ONLY FOR ONE PERIOD.
THEN ENSEMBLES ARE BEGINNING TO SUGGEST BROAD RIDGING WILL DEVELOP
ACROSS THE SOUTHWEST CONUS...WHICH COULD SHIFT THE NORTHWEST FLOW
ORIENTATION TO THE NORTHEAST. ROBUST THERMAL TROUGH SWINGS OVER THE
REGION THUR...BRINGING MUCH COOLER AIR BACK WITH HIGHS IN THE SINGLE
DIGITS TO LOW TEENS. THUR NGT TEMPS COULD THEN DROP BELOW ZERO.
THEN FOR THE START OF THE UPCOMING WEEKEND TEMPS COULD WARM BACK
INTO THE LOW 30S.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SNOW THROUGH TONIGHT. LIGHT LAKE EFFECT SNOW EARLY MONDAY MAINLY
FOR MDW. PREVAILING VIS AT OR UNDER 1SM THROUGH THIS EVENING.
* NELY WINDS GUSTING TO 30-35 KT LATE THIS AFTERNOON/EARLY
EVENING.
* BLOWING AND DRIFTING SNOW LIKELY THIS AFTERNOON AND TONIGHT.
* PERIODS OF VIS 1/4SM OR LESS THIS AFTERNOON WHEN GUSTS INCREASE
TO 30 KT AND HIGHER.
* IFR-LIFR CIGS THROUGH LATE EVENING.
KMD
//DISCUSSION...UPDATED 18Z...
STEADY SNOWFALL CONTINUES THROUGH THE AFTERNOON AND EVENING. THE
SNOW HAS BEEN WET TO THIS POINT...BUT FROM NORTH TO SOUTH IT WILL
SHIFT TO A DRIER SNOW AS THE AFTERNOON AND EVENING GO ON.
VISIBILITIES HAVE BEEN LARGELY STEADY AROUND 1/2 MILE...AND WHILE
FLUCTUATIONS IN THIS WILL OCCUR FROM TIME TO TIME...EXPECT 1/2 TO
3/4 VSBYS TO GENERALLY BE THE RULE. AS THE WINDS RAMP UP LATER THIS
AFTERNOON AND EVENING...FEEL THAT THERE WILL BE OCCASIONAL 1/4 MILE
VISIBILITIES AS THE SNOW GETS A BIT MORE BLOWABLE...BUT STILL NOT
CONFIDENT IN THIS CONDITION PREVAILING. WILL HAVE TO MONITOR AS THE
WINDS RAMP UP. IF THIS WERE TO OCCUR...IT WOULD BE THE LATE
AFTERNOON AND EARLY EVENING PERIOD WHEN THE SURFACE LOW MOVES A BIT
FARTHER NORTH AND EAST. THINK THAT THE 22Z-02Z TIME FRAME WOULD BE
THE BEST BET FOR THIS. WINDS HOLD IN THE 050 DIRECTION THEN BACK
THROUGH THE EVENING TO 020 BY MID EVENING...THEN NNW OVERNIGHT.
SHOULD SEE SOME SLIGHTY IMPROVEMENT IN VSBY AND DECREASE IN SNOWFALL
FROM 4Z-6Z...AND AFTER 6Z SNOWFALL SHOULD DECREASE SIGNIFICANTLY
THOUGH NOT END...AND WINDS SHOULD START A MORE SIGNIFICANT
DOWNWARD TREND. EXPECT LIGHT LAKE EFFECT SNOW SHOWERS OVERNIGHT.
MOST TERMINALS EXCEPT MDW AND GYY SHOULD BE DRY BY DAYBREAK WITH A
WEAKENING WESTERLY WIND.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE IN WX/VIS TRENDS.
* MEDIUM CONFIDENCE IN CIG TRENDS.
* MEDIUM CONFIDENCE IN TIMING OF IMPROVING CIG/VIS.
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR/WX NIL EARLY. CHANCE SNOW WITH MVFR CIGS/VIS
LATE.
TUESDAY...SLIGHT CHANCE SNOW EARLY WITH MVFR CIGS/VIS. VFR/WX NIL
AFTERNOON. SNOW LIKELY WITH IFR CIG/VIS OVERNIGHT.
WEDNESDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS EARLY. VFR/WX NIL
OVERNIGHT.
THURSDAY...VFR/WX NIL.
FRIDAY...VFR/WX NIL.
SATURDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS POSSIBLE.
KREIN
&&
.MARINE...
135 PM CST
LOW PRESSURE HAS BEEN SLOW TO LIFT NORTHEAST ACROSS THE OHIO
VALLEY...REACHING EAST CENTRAL IL BY EARLY THIS AFTERNOON. THIS
LOW CONTINUES TO DEEPEN AND WILL ALLOW FOR GALES TO INCREASE FROM
35 KT TO LIKELY CLOSER TO 40 KT. THE FAR NORTHERN PORTIONS OF LAKE
MICHIGAN MAY STRUGGLE TO SEE THE STRONGER GRADIENT DEVELOP AND
STRONGER GALES...BUT THE EXPECTATION IS THAT GALES WILL EVENTUALLY
REACH THE NORTHERN PORTIONS LATER THIS EVENING. WITH MUCH COLDER
AIR SLIDING ACROSS THE LAKE WITH GALE CONDITIONS...HEAVY FREEZING
SPRAY WILL BE LIKELY. LOW PRESSURE WILL THEN SLIDE NORTHEAST LATE
TONIGHT...AND THIS WILL ALLOW THE GRADIENT TO STEADILY RELAX
OVERNIGHT. THIS WILL GALES/FREEZING SPRAY TO COME TO AN END LATE
TONIGHT. BROAD HIGH PRESSURE WILL BUILD IN EARLY MONDAY...BRINGING
MUCH LIGHTER WINDS TO LAKE MICHIGAN.
THE FLOW REMAINS RELATIVELY ACTIVE...WITH THE HIGH PRESSURE
QUICKLY SLIDING EAST MONDAY EVENING AND FLOW TURNING
SOUTHWESTERLY. THE GRADIENT BEGINS TO INCREASE LATE MONDAY NIGHT
INTO TUESDAY...BUT AT THIS TIME IT APPEARS WINDS WILL REMAIN
BETWEEN 10-20KT POSSIBLY UP TO 25KT.
A SERIES OF LOW PRESSURE SYSTEMS WILL CONTINUE TO FEED FROM WEST
TO EAST ACROSS LAKE MICHIGAN THROUGH MID-WEEK...BUT AT THIS TIME
THE SYSTEMS ARE NOT EXPECTED TO BE STRONG.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...LAKESHORE FLOOD ADVISORY...ILZ006-ILZ014 UNTIL 10 AM MONDAY.
BLIZZARD WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022
UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...ILZ023-ILZ032-ILZ033-ILZ039 UNTIL
MIDNIGHT MONDAY.
IN...BLIZZARD WARNING...INZ001 UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...INZ002-INZ010-INZ011-INZ019 UNTIL
MIDNIGHT MONDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
119 PM CST SUN FEB 1 2015
.UPDATE...
WE HAVE INCREASED SNOWFALL AMOUNTS SOME THIS AFTERNOON...ESPECIALLY
ACROSS NORTHERN ILLINOIS AND FAR NORTHWESTERN INDIANA. A VERY
IMPRESSIVE SYSTEM CONTINUES TO DEVELOP ACROSS THE CENTRAL CONUS THIS
MORNING IN RESPONSE TO A STRONG PV ANOMALY OVER THE CENTRAL PLAINS.
AS THIS STORM CONTINUES TO INTENSIFY THIS AFTERNOON...MODEL GUIDANCE
SUGGESTS THAT A BAND OF STRONG FRONTOGENESIS WILL DEVELOP IN AN
EMERGING DEFORMATION ZONE ASSOCIATED WITH THE 700 MB LOW...RIGHT
ACROSS NORTHERN ILLINOIS. THIS ALSO LOOKS TO OCCUR DURING THE
PERIOD OF BEST STRONG MID/UPPER LEVEL Q-VECTOR DIVERGENCE
ASSOCIATED WITH THE MID/UPPER LEVEL SYSTEM. ALL IN ALL THIS POINTS
TO STRONG DYANAMICS SUPPORTIVE OF PERIODS OF HEAVY SNOW THROUGH
THE DAY TODAY...AND LINGERING THIS EVENING. IT APPEARS THE
HEAVIEST AMOUNTS WILL EXCEED A FOOT IN MANY AREAS...WITH A FOOT
AND A HALF NOT OUT OF THE QUESTION FOR NORTHERN ILLINOIS.
THE OTHER CONCERN IS BLIZZARD CONDITIONS...WE ARE UPGRADING THE REST
OF NORTH CENTRAL ILLINOIS TO A BLIZZARD WARNING. NORTHEASTERLY
WINDS WILL ONLY INCREASE THROUGH THE AFTERNOON...WITH GUSTS
POTENTIAL UP AROUND 40 KT AT TIMES GIVEN THE STRONG GRADIENT SETTING
UP ON THE BACK SIDE OF THIS SYSTEM. THIS HAS ME SERIOUSLY CONCERNED
THAT AS THE SNOW CONTINUES TO BECOME MORE POWDERY THROUGH THE
DAY...THAT WHITE OUT CONDITIONS WILL BE OBSERVED ACROSS NORTHERN
ILLINOIS. THE OTHER CONCERN IS FOR DOWNED TREE BRANCHES AND POWER
LINES. THE SNOW THAT HAS FALLEN THUS FAR ACROSS THE AREA HAS BEEN A
STICKY WET SNOW AND HAS PRODUCED SIGNIFICANT ACCUMULATIONS ON TREES
AND POWER LINES. THE INCREASING WINDS COULD BRING DOWN POWER
LINES...LEADING TO SOME ISOLATED POWER OUTAGES.
NEW UPDATES SHOULD BE OUT SHORTLY.
KJB
&&
.SHORT TERM...
347 AM CST
THROUGH MONDAY...
HAVE BEEN SWAMPED THIS MORNING AND AM RUNNING BEHIND...SO GOING TO
KEEP DISCUSSION BRIEF THIS MORNING AND JUST HIT THE IMPORTANT
CHANGES. THE BIGGEST CHANGES TO GOING FORECAST IS THE UPGRADE TO
A BLIZZARD WARNING FOR PORTIONS OF NE IL/CHICAGO METRO AND TO
LOWER SNOW AMOUNTS AND ADD MIXED PRECIP BACK INTO GRIDS FAR SE
CWA.
GUIDANCE HAS CONTINUED TO TREND NORTH AND STRONGER WITH THE TRACK OF
THIS SYSTEM AND COMPARING GUIDANCE WITH SFC OBS AND BEST SFC
PRESSURE FALLS IT WOULD SEEM TO SUPPORT THE FARTHER NORTH TRACK THAT
THE RAP IN PARTICULAR HAS LATCHED ONTO. THE SOMEWHAT DEEPER LOW
ALONG WITH THE VERY STRONG ARCTIC HIGH SPREADING SOUTHEAST WILL
RESULT IN VERY STRONG WINDS DEVELOPING THIS AFTERNOON. INCREASING
LOW LEVEL COLD AIR ADVECTION AND SFC HEIGHT RISES FAVOR PRETTY GOOD
MIXING IN THE BOUNDARY LAYER...WHICH IS WHAT ALL MODEL FORECAST
SOUNDINGS ARE ADVERTISING. TAKING EVEN THE BEST CASE SCENARIO AND
ONE OF THE WEAKEST MODELS BUFKIT MOMENTUM TRANSFER VALUES SUPPORT
4-7 HOURS OF WIND GUSTS BETWEEN 35-40 MPH LATER THIS AFTERNOON AND
EVENING...WITH MORE AGGRESSIVE GFS/RAP SUPPORTING EVEN STRONGER
WINDS OVER A LONGER DURATION. SNOW HAS BEEN WET THUS FAR BUT WITH
TIME SHOULD SEE THE TRANSITION TOWARD DRIER/MORE BLOWABLE SNOW THIS
AFTERNOON FROM NORTH TO SOUTH AS THE COLUMN COOLS AND THE SNOW
LIQUID CONTENT DECREASES. BIGGEST UNCERTAINTY REVOLVES AROUND
REGARDING UPGRADE TO BLIZZARD WARNING WAS THE SNOW LIQUID CONTENT
AND PROBABILITY AND CONFIDENCE IS CERTAINLY HIGHER THE FARTHER NORTH
FROM I-80 THAT YOU GET...BUT EVEN AS FAR SOUTH AS I-80 FELT FAIRLY
CONFIDENT THAT WHITE OUT CONDITIONS COULD DEVELOP LATE THIS
AFTERNOON AND ESPECIALLY THIS EVENING. FARTHER WEST ACROSS NORTH
CENTRAL ILLINOIS FEEL THAT A BLIZZARD WARNING COULD EASILY BE
JUSTIFIED...BUT IN COORDINATION WITH MKX/DVN HAVE OPTED TO HOLD OFF
FOR NOW AS SNOW INTENSITY COULD BE DECREASING AS WINDS PICK UP.
QUITE POSSIBLE DAY SHIFT MAY NEED TO RE-ACCESS THIS AND AN UPGRADE
TO BLIZZARD WARNING FOR RFD AND POINTS WEST COULD OCCUR ON THE DAY
SHIFT.
OTHER BIG CHANGE TO FORECAST WAS TO ADD SLEET AND THEN DRIZZLE TO
THE FAR SOUTHEAST CWA. SFC TEMPS HAVE BEEN A BIT WARMER AND THE
FARTHER NORTH TRACK OF THE SFC LOW SHOULD KEEP LOW LEVEL WAA GOING
INTO EARLY AFTERNOON WITH AT LEAST THE THREAT OF MIXED
PRECIP...POSSIBLY TRANSITIONING OVER TO JUST DRIZZLE/SNIZZLE AS MID
LEVEL DRY SLOT OVERSPREADS THAT AREA REMOVING ICE NUCLEI FROM THE
CLOUDS LATE THIS AFTERNOON INTO THIS EVENING. THE WETTER SNOW SOUTH
OF I-80 SHOULD RESULT IN LESS SEVERE AND LESS IMPACTFUL
BLOWING/DRIFTING SNOW. GIVEN THE MARGINAL TEMPS AND POTENTIAL MIX
PRECIP HAVE CUT BACK ON ACCUMS IN THE FAR SOUTHEAST COUNTIES OF THE
CWA.
ACCUMULATING LAKE EFFECT POTENTIAL ACTUALLY LOOKS SOMEWHAT LESS
IMPRESSIVE THAN IT DID LAST NIGHT...AND IT WAS ALREADY LOOKING
MARGINAL. SOME SYSTEM SNOWS SHOULD LINGER INTO THIS EVENING BUT LAKE
CONTRIBUTIONS LOOK MINOR WITH LOW INVERSION HEIGHTS AND DECREASING
BOUNDARY LAYER RH AS THE THERMODYNAMICS IMPROVE EVER SO SLIGHTLY.
ANY LAKE ENHANCEMENT TO SNOW TOTALS SHOULD END UP BEING TRIVIAL.
FINALLY...GOING SNOWFALL TOTALS LOOK RIGHT ON TARGET AND MADE VERY
FEW CHANGES OTHER THAN IN SE AS NOTED ABOVE. A RESPECTABLY LARGE
SWATH OF A FOOT OR MORE OF SNOW STILL LOOKS LIKELY AND PROBABLY
CENTERED RELATIVELY CLOSE TO THE I-80 TO I-88/290 CORRIDORS.
ACTUALLY THINKING THAT MAX SNOWFALL TOTALS IN THE CWA COULD END UP
BEING ON THE HIGH END OF THE 10-14 INCH RANGE WITH LOCALIZED TOTALS
POTENTIALLY PUSHING A FOOT AND A HALF IF THE DEFO BAND IS INDEED AS
IMPRESSIVE AS SOME OF THE GUIDANCE WOULD SUGGEST. WHILE SNOWFALL
TOTALS WILL BE VERY IMPRESSIVE OVER MOST OF THE CWA...IT IS
IMPORTANT TO REMEMBER THE BLIZZARD WARNING IS ISSUED NOT FOR
SNOWFALL AMOUNTS BUT RATHER FOR VISIBILITY AND WINDS. THE CRITERIA
FOR BLIZZARD WARNING IS 3+ HOURS OF LESS THAN 1/4SM VSBY IN FALLING
AND/OR BLOWING SNOW ALONG WITH SUSTAINED WINDS OR FREQUENT GUSTS
OVER 35 MPH.
IZZI
&&
.LONG TERM...
118 PM CST
MONDAY THROUGH MONDAY NIGHT...
LOW PRESSURE WILL CONTINUE TO DEPART THE REGION TO THE EAST...WITH
ANTI-CYCLONIC FLOW REPLACING IT OVER THE FORECAST AREA FOR MON.
LONGWAVE FLOW PATTERN CONTINUES TO BE IN A SOMEWHAT NORTHWEST
ORIENTATION. THIS COUPLED WITH THE SFC RIDGE CENTER POSITIONED
JUST SOUTH OF THE CWFA WILL KEEP WINDS GENERALLY FROM THE
WEST/NORTHWEST. ENOUGH DRY AIR SHUD MIX DOWN TO THE SFC AND ERODE
THE BULK OF THE CLOUDS...HOWEVER NOT TOO CONFIDENT THAT CLEAR
SKIES WILL LINGER VERY LONG. THE FLOW WILL REMAIN PROGRESSIVE AND
HELP TO PUSH THE SFC RIDGE EAST/SOUTHEAST OF THE AREA BY LATE MON
NGT.
THIS WILL SETUP A WEAK MID-LVL WAVE SLIDING SOUTHEAST ACROSS THE
NORTHERN PLAINS TO ARRIVE LATE MON NGT IN THE FAR WESTERN CWFA. LLVL
FLOW WILL TURN SOUTHWESTERLY AND COULD KEEP SOME DRY AIR LOCKED IN
LONG ENOUGH TO KEEP ANY PRECIP WEST OF THE FORECAST AREA UNTIL LATE
MON NGT.
HIGHS MON WILL STRUGGLE TO WARM DESPITE THE THINNING SOLAR
SHIELDING...WITH TEMPS GENERALLY IN THE LOW/MID TEENS. THEN MON NGT
TEMPS ALOFT WILL EASILY RADIATE WITH LGT WINDS AND THIN CLOUD COVER.
FRESH SNOW PACK WILL LIKELY HELP TEMPS TO COOL INTO THE SINGLE
DIGITS ABOVE ZERO. WITH CLOUDS RETURNING LATE MON NGT FROM A WEAK
MID-LVL SYSTEM...TEMPS COULD RISE A DEGREE OR TWO AFTER
MIDNIGHT/EARLY TUE.
CURRENT EXPECTATION IS THAT ANY ACCUMULATIONS MON NGT WOULD BE LESS
THAN ONE HALF INCH.
TUESDAY THROUGH WEDNESDAY...
WITH A MID-LVL WAVE PIVOTING EAST OVERHEAD TUE MORNING...LLVL FLOW
WILL REMAIN SOUTHWESTERLY WITH SOME WEAK WARM AIR ADVECTING INTO THE
FORECAST AREA. TEMPS SHUD WARM INTO THE 20S TUE...AND WITH A GOOD
PUSH OF WARM AIR ADVECTION IN THE SOUTHERN TIER OF COUNTIES...TEMPS
COULD TAG 30 DEGREES TUE AFTN.
500MB TROUGH AXIS IS PROGGED TO SEND YET ANOTHER MID-LVL WAVE DIVING
SOUTHEAST ACROSS THE NORTHERN PLAINS TUE MORNING. GUIDANCE HAS
CONTINUED TO PROG THE ARRIVAL OF THIS FEATURE INTO THE CWFA TUE NGT.
FORCING APPEARS TO BE RATHER WEAK...HOWEVER ENOUGH MOISTURE AND LIFT
COULD EASILY PRODUCE SOME LGT SNOW ONCE AGAIN LATE TUE NGT. AT THIS
TIME IT WOULD APPEAR AROUND 1 INCH OF SNOW.
CONSIDERABLE CLOUDINESS TUE NGT WILL HELP TO HOLD TEMPS UP...WITH
OVERNIGHT LOWS IN THE UPR TEENS TO MID 20S.
SOME LINGERING LGT SNOW WED MORNING...WITH FLOW STARTING TO FLATTEN
BY MIDDAY WED. AS THE LOW LIFTS NORTHEAST WED MORNING ACROSS LOWER
MI...A TRAILING BOUNDARY WILL SLOWLY SAG SOUTH ACROSS THE WESTERN
GREAT LAKES AND MID-MISSOURI VALLEY. A WEAK WAVE WILL TRY TO DEVELOP
OVER THE CENTRAL PLAINS EARLY WED...AND COULD BRING ADDTL LGT PRECIP
BACK INTO THE FAR WEST/SOUTHWEST CWFA LATE WED AFTN.
WEDNESDAY NIGHT THROUGH SATURDAY...
ENSEMBLES CONTINUE THE THEME OF AN ACTIVE FLOW...WITH TROUGHING
GENERALLY OVER THE GREAT LAKES REGION AND RIDGING REMAINING OVER
WESTERN CANADA. THERE IS SOME WEAK FLATTENING IN THE LONGWAVE
PATTERN THUR...BUT THIS APPEARS TO BE ONLY FOR ONE PERIOD.
THEN ENSEMBLES ARE BEGINNING TO SUGGEST BROAD RIDGING WILL DEVELOP
ACROSS THE SOUTHWEST CONUS...WHICH COULD SHIFT THE NORTHWEST FLOW
ORIENTATION TO THE NORTHEAST. ROBUST THERMAL TROUGH SWINGS OVER THE
REGION THUR...BRINGING MUCH COOLER AIR BACK WITH HIGHS IN THE SINGLE
DIGITS TO LOW TEENS. THUR NGT TEMPS COULD THEN DROP BELOW ZERO.
THEN FOR THE START OF THE UPCOMING WEEKEND TEMPS COULD WARM BACK
INTO THE LOW 30S.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SNOW THROUGH TONIGHT. LIGHT LAKE EFFECT SNOW EARLY MONDAY MAINLY
FOR MDW. PREVAILING VIS AT OR UNDER 1SM THROUGH THIS EVENING.
* NELY WINDS GUSTING TO 30-35 KT LATE THIS AFTERNOON/EARLY
EVENING.
* BLOWING AND DRIFTING SNOW LIKELY THIS AFTERNOON AND TONIGHT.
* PERIODS OF VIS 1/4SM OR LESS THIS AFTERNOON WHEN GUSTS INCREASE
TO 30 KT AND HIGHER.
* IFR-LIFR CIGS THROUGH LATE EVENING.
KMD
//DISCUSSION...UPDATED 18Z...
STEADY SNOWFALL CONTINUES THROUGH THE AFTERNOON AND EVENING. THE
SNOW HAS BEEN WET TO THIS POINT...BUT FROM NORTH TO SOUTH IT WILL
SHIFT TO A DRIER SNOW AS THE AFTERNOON AND EVENING GO ON.
VISIBILITIES HAVE BEEN LARGELY STEADY AROUND 1/2 MILE...AND WHILE
FLUCTUATIONS IN THIS WILL OCCUR FROM TIME TO TIME...EXPECT 1/2 TO
3/4 VSBYS TO GENERALLY BE THE RULE. AS THE WINDS RAMP UP LATER THIS
AFTERNOON AND EVENING...FEEL THAT THERE WILL BE OCCASIONAL 1/4 MILE
VISIBILITIES AS THE SNOW GETS A BIT MORE BLOWABLE...BUT STILL NOT
CONFIDENT IN THIS CONDITION PREVAILING. WILL HAVE TO MONITOR AS THE
WINDS RAMP UP. IF THIS WERE TO OCCUR...IT WOULD BE THE LATE
AFTERNOON AND EARLY EVENING PERIOD WHEN THE SURFACE LOW MOVES A BIT
FARTHER NORTH AND EAST. THINK THAT THE 22Z-02Z TIME FRAME WOULD BE
THE BEST BET FOR THIS. WINDS HOLD IN THE 050 DIRECTION THEN BACK
THROUGH THE EVENING TO 020 BY MID EVENING...THEN NNW OVERNIGHT.
SHOULD SEE SOME SLIGHTY IMPROVEMENT IN VSBY AND DECREASE IN SNOWFALL
FROM 4Z-6Z...AND AFTER 6Z SNOWFALL SHOULD DECREASE SIGNIFICANTLY
THOUGH NOT END...AND WINDS SHOULD START A MORE SIGNIFICANT
DOWNWARD TREND. EXPECT LIGHT LAKE EFFECT SNOW SHOWERS OVERNIGHT.
MOST TERMINALS EXCEPT MDW AND GYY SHOULD BE DRY BY DAYBREAK WITH A
WEAKENING WESTERLY WIND.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE IN WX/VIS TRENDS.
* MEDIUM CONFIDENCE IN CIG TRENDS.
* MEDIUM CONFIDENCE IN TIMING OF IMPROVING CIG/VIS.
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR/WX NIL EARLY. CHANCE SNOW WITH MVFR CIGS/VIS
LATE.
TUESDAY...SLIGHT CHANCE SNOW EARLY WITH MVFR CIGS/VIS. VFR/WX NIL
AFTERNOON. SNOW LIKELY WITH IFR CIG/VIS OVERNIGHT.
WEDNESDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS EARLY. VFR/WX NIL
OVERNIGHT.
THURSDAY...VFR/WX NIL.
FRIDAY...VFR/WX NIL.
SATURDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS POSSIBLE.
KREIN
&&
.MARINE...
315 AM CST
THE SFC LOW OVER THE PLAINS LOOKS TO BE DEEPENING A LITTLE FASTER
AND LOWER WHILE THE HIGH PRESSURE RIDGING OVER THE UPPER GREAT
LAKES IS TRENDING A LITTLE STRONGER. THIS COMBINATION WITH STRONG
COLD ADVECTION SETTING UP OVER THE LAKE TODAY...HAVE EXPANDED THE
GALE WARNING OVER THE ENTIRE OPEN WATERS OF LAKE MICHIGAN AS WELL
AS EXTENDING IN TIME...STARTING A LITTLE EARLIER...AT 15Z THIS
MORNING AND GOING A LITTLE LATER...TO 09Z TONIGHT. ALSO...HAVE
INCREASED GALES TO 40KT OVER THE SOUTHERN PORTIONS OF THE LAKE
WHERE THE PRESSURE GRADIENT AND PRESSURE FALLS ARE STRONGEST. AS
THE WINDS PICK UP TO GALE FORCE AND MUCH COLDER AIR FILTERS OVER
THE LAKE LATER TODAY...HEAVY FREEZING SPRAY WILL BE LIKELY...SO
HAVE ALSO ISSUED A HEAVY FREEZING SPRAY WARNING FROM 15Z THIS
MORNING TO 09Z TONIGHT. THE COLDER AIR WILL SPREAD OVER THE
NORTHERN PORTIONS OF THE LAKE EARLIER THAN THE SOUTHERN
PORTIONS...SO IT IS POSSIBLE THAT THE HEAVY FREEZING SPRAY
POTENTIAL MAY NOT REACH THE SOUTHERN PORTIONS OF THE LAKE UNTIL
THIS AFTERNOON...BUT WENT WITH ONE SEGMENT TO THE WARNING TO
COINCIDE WITH THE GALE WARNING TIMING. THE LOW SHOULD PUSH EAST
INTO THE MID ATLANTIC REGION BE MONDAY AFTERNOON...WHILE HIGH
PRESSURE SPREADS ACROSS THE MISSISSIPPI RIVER INTO THE WESTERN
GREAT LAKES REGION. THIS WILL LEAD TO SUBSIDING WINDS AND
WAVES...ESPECIALLY AS WEAK HIGH PRESSURE PRESSURE CROSSES THE LAKE
MONDAY NIGHT AND TUESDAY.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...LAKESHORE FLOOD ADVISORY...ILZ006-ILZ014 UNTIL 10 AM MONDAY.
BLIZZARD WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022
UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...ILZ023-ILZ032-ILZ033-ILZ039 UNTIL
MIDNIGHT MONDAY.
IN...BLIZZARD WARNING...INZ001 UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...INZ002-INZ010-INZ011-INZ019 UNTIL
MIDNIGHT MONDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1230 PM CST SUN FEB 1 2015
.UPDATE...
WE HAVE INCREASED SNOWFALL AMOUNTS SOME THIS AFTERNOON...ESPECIALLY
ACROSS NORTHERN ILLINOIS AND FAR NORTHWESTERN INDIANA. A VERY
IMPRESSIVE SYSTEM CONTINUES TO DEVELOP ACROSS THE CENTRAL CONUS THIS
MORNING IN RESPONSE TO A STRONG PV ANOMALY OVER THE CENTRAL PLAINS.
AS THIS STORM CONTINUES TO INTENSIFY THIS AFTERNOON...MODEL GUIDANCE
SUGGESTS THAT A BAND OF STRONG FRONTOGENESIS WILL DEVELOP IN AN
EMERGING DEFORMATION ZONE ASSOCIATED WITH THE 700 MB LOW...RIGHT
ACROSS NORTHERN ILLINOIS. THIS ALSO LOOKS TO OCCUR DURING THE
PERIOD OF BEST STRONG MID/UPPER LEVEL Q-VECTOR DIVERGENCE
ASSOCIATED WITH THE MID/UPPER LEVEL SYSTEM. ALL IN ALL THIS POINTS
TO STRONG DYANAMICS SUPPORTIVE OF PERIODS OF HEAVY SNOW THROUGH
THE DAY TODAY...AND LINGERING THIS EVENING. IT APPEARS THE
HEAVIEST AMOUNTS WILL EXCEED A FOOT IN MANY AREAS...WITH A FOOT
AND A HALF NOT OUT OF THE QUESTION FOR NORTHERN ILLINOIS.
THE OTHER CONCERN IS BLIZZARD CONDITIONS...WE ARE UPGRADING THE REST
OF NORTH CENTRAL ILLINOIS TO A BLIZZARD WARNING. NORTHEASTERLY
WINDS WILL ONLY INCREASE THROUGH THE AFTERNOON...WITH GUSTS
POTENTIAL UP AROUND 40 KT AT TIMES GIVEN THE STRONG GRADIENT SETTING
UP ON THE BACK SIDE OF THIS SYSTEM. THIS HAS ME SERIOUSLY CONCERNED
THAT AS THE SNOW CONTINUES TO BECOME MORE POWDERY THROUGH THE
DAY...THAT WHITE OUT CONDITIONS WILL BE OBSERVED ACROSS NORTHERN
ILLINOIS. THE OTHER CONCERN IS FOR DOWNED TREE BRANCHES AND POWER
LINES. THE SNOW THAT HAS FALLEN THUS FAR ACROSS THE AREA HAS BEEN A
STICKY WET SNOW AND HAS PRODUCED SIGNIFICANT ACCUMULATIONS ON TREES
AND POWER LINES. THE INCREASING WINDS COULD BRING DOWN POWER
LINES...LEADING TO SOME ISOLATED POWER OUTAGES.
NEW UPDATES SHOULD BE OUT SHORTLY.
KJB
&&
.SHORT TERM...
347 AM CST
THROUGH MONDAY...
HAVE BEEN SWAMPED THIS MORNING AND AM RUNNING BEHIND...SO GOING TO
KEEP DISCUSSION BRIEF THIS MORNING AND JUST HIT THE IMPORTANT
CHANGES. THE BIGGEST CHANGES TO GOING FORECAST IS THE UPGRADE TO
A BLIZZARD WARNING FOR PORTIONS OF NE IL/CHICAGO METRO AND TO
LOWER SNOW AMOUNTS AND ADD MIXED PRECIP BACK INTO GRIDS FAR SE
CWA.
GUIDANCE HAS CONTINUED TO TREND NORTH AND STRONGER WITH THE TRACK OF
THIS SYSTEM AND COMPARING GUIDANCE WITH SFC OBS AND BEST SFC
PRESSURE FALLS IT WOULD SEEM TO SUPPORT THE FARTHER NORTH TRACK THAT
THE RAP IN PARTICULAR HAS LATCHED ONTO. THE SOMEWHAT DEEPER LOW
ALONG WITH THE VERY STRONG ARCTIC HIGH SPREADING SOUTHEAST WILL
RESULT IN VERY STRONG WINDS DEVELOPING THIS AFTERNOON. INCREASING
LOW LEVEL COLD AIR ADVECTION AND SFC HEIGHT RISES FAVOR PRETTY GOOD
MIXING IN THE BOUNDARY LAYER...WHICH IS WHAT ALL MODEL FORECAST
SOUNDINGS ARE ADVERTISING. TAKING EVEN THE BEST CASE SCENARIO AND
ONE OF THE WEAKEST MODELS BUFKIT MOMENTUM TRANSFER VALUES SUPPORT
4-7 HOURS OF WIND GUSTS BETWEEN 35-40 MPH LATER THIS AFTERNOON AND
EVENING...WITH MORE AGGRESSIVE GFS/RAP SUPPORTING EVEN STRONGER
WINDS OVER A LONGER DURATION. SNOW HAS BEEN WET THUS FAR BUT WITH
TIME SHOULD SEE THE TRANSITION TOWARD DRIER/MORE BLOWABLE SNOW THIS
AFTERNOON FROM NORTH TO SOUTH AS THE COLUMN COOLS AND THE SNOW
LIQUID CONTENT DECREASES. BIGGEST UNCERTAINTY REVOLVES AROUND
REGARDING UPGRADE TO BLIZZARD WARNING WAS THE SNOW LIQUID CONTENT
AND PROBABILITY AND CONFIDENCE IS CERTAINLY HIGHER THE FARTHER NORTH
FROM I-80 THAT YOU GET...BUT EVEN AS FAR SOUTH AS I-80 FELT FAIRLY
CONFIDENT THAT WHITE OUT CONDITIONS COULD DEVELOP LATE THIS
AFTERNOON AND ESPECIALLY THIS EVENING. FARTHER WEST ACROSS NORTH
CENTRAL ILLINOIS FEEL THAT A BLIZZARD WARNING COULD EASILY BE
JUSTIFIED...BUT IN COORDINATION WITH MKX/DVN HAVE OPTED TO HOLD OFF
FOR NOW AS SNOW INTENSITY COULD BE DECREASING AS WINDS PICK UP.
QUITE POSSIBLE DAY SHIFT MAY NEED TO RE-ACCESS THIS AND AN UPGRADE
TO BLIZZARD WARNING FOR RFD AND POINTS WEST COULD OCCUR ON THE DAY
SHIFT.
OTHER BIG CHANGE TO FORECAST WAS TO ADD SLEET AND THEN DRIZZLE TO
THE FAR SOUTHEAST CWA. SFC TEMPS HAVE BEEN A BIT WARMER AND THE
FARTHER NORTH TRACK OF THE SFC LOW SHOULD KEEP LOW LEVEL WAA GOING
INTO EARLY AFTERNOON WITH AT LEAST THE THREAT OF MIXED
PRECIP...POSSIBLY TRANSITIONING OVER TO JUST DRIZZLE/SNIZZLE AS MID
LEVEL DRY SLOT OVERSPREADS THAT AREA REMOVING ICE NUCLEI FROM THE
CLOUDS LATE THIS AFTERNOON INTO THIS EVENING. THE WETTER SNOW SOUTH
OF I-80 SHOULD RESULT IN LESS SEVERE AND LESS IMPACTFUL
BLOWING/DRIFTING SNOW. GIVEN THE MARGINAL TEMPS AND POTENTIAL MIX
PRECIP HAVE CUT BACK ON ACCUMS IN THE FAR SOUTHEAST COUNTIES OF THE
CWA.
ACCUMULATING LAKE EFFECT POTENTIAL ACTUALLY LOOKS SOMEWHAT LESS
IMPRESSIVE THAN IT DID LAST NIGHT...AND IT WAS ALREADY LOOKING
MARGINAL. SOME SYSTEM SNOWS SHOULD LINGER INTO THIS EVENING BUT LAKE
CONTRIBUTIONS LOOK MINOR WITH LOW INVERSION HEIGHTS AND DECREASING
BOUNDARY LAYER RH AS THE THERMODYNAMICS IMPROVE EVER SO SLIGHTLY.
ANY LAKE ENHANCEMENT TO SNOW TOTALS SHOULD END UP BEING TRIVIAL.
FINALLY...GOING SNOWFALL TOTALS LOOK RIGHT ON TARGET AND MADE VERY
FEW CHANGES OTHER THAN IN SE AS NOTED ABOVE. A RESPECTABLY LARGE
SWATH OF A FOOT OR MORE OF SNOW STILL LOOKS LIKELY AND PROBABLY
CENTERED RELATIVELY CLOSE TO THE I-80 TO I-88/290 CORRIDORS.
ACTUALLY THINKING THAT MAX SNOWFALL TOTALS IN THE CWA COULD END UP
BEING ON THE HIGH END OF THE 10-14 INCH RANGE WITH LOCALIZED TOTALS
POTENTIALLY PUSHING A FOOT AND A HALF IF THE DEFO BAND IS INDEED AS
IMPRESSIVE AS SOME OF THE GUIDANCE WOULD SUGGEST. WHILE SNOWFALL
TOTALS WILL BE VERY IMPRESSIVE OVER MOST OF THE CWA...IT IS
IMPORTANT TO REMEMBER THE BLIZZARD WARNING IS ISSUED NOT FOR
SNOWFALL AMOUNTS BUT RATHER FOR VISIBILITY AND WINDS. THE CRITERIA
FOR BLIZZARD WARNING IS 3+ HOURS OF LESS THAN 1/4SM VSBY IN FALLING
AND/OR BLOWING SNOW ALONG WITH SUSTAINED WINDS OR FREQUENT GUSTS
OVER 35 MPH.
IZZI
&&
.LONG TERM...
MONDAY NIGHT THROUGH SATURDAY...
134 AM...FORECAST CONCERNS INCLUDE A CHANCE OF LIGHT SNOW MONDAY
NIGHT INTO TUESDAY...THEN A BETTER CHANCE FOR ACCUMULATING LIGHT
SNOW TUESDAY NIGHT INTO WEDNESDAY MORNING.
A RIDGE OF HIGH PRESSURE WILL BE MOVING SOUTHEAST OF THE AREA
MONDAY EVENING AS A WEAK WAVE MOVES ACROSS THE REGION MONDAY NIGHT.
FAIRLY LIGHT QPF FROM ALL THE MODELS WITH THIS WAVE BUT PLENTY COLD
ENOUGH FOR THE LOW QPF AMOUNTS TO POTENTIALLY FLUFF UP TO A HALF
INCH MONDAY NIGHT. WHILE TEMPS BY THIS TIME WILL LIKELY BE IN THE
SINGLE DIGITS OR LOW TEENS...CLOUD COVER AND WEAK WARM AIR ADVECTION
MAY ALLOW TEMPS TO HOLD STEADY OR RISE A FEW DEGREES OVERNIGHT.
NEXT WAVE QUICKLY SHIFTS SOUTHEAST ACROSS THE AREA BY TUESDAY
EVENING WITH QPF AMOUNTS BETWEEN ONE AND TWO TENTHS. THIS HAS BEEN
A FAIRLY CONSISTENT FEATURE ON THE MODELS AND IF THIS MATERIALIZES
AS ADVERTISED...A FEW INCHES OF SNOW WILL BE POSSIBLE. TIMING AND
LOCATION ALSO ARE A BIT UNCERTAIN...EARLIER COULD IMPACT THE TUESDAY
EVENING RUSH...LATER COULD IMPACT THE WEDNESDAY MORNING RUSH. BUT
GIVEN THE POTENTIAL FOR SOME ACCUMULATION...OPTED TO BUMP POPS UP TO
LIKELY FOR TUESDAY NIGHT.
HIGH PRESSURE THEN SETTLES SOUTH ACROSS THE MIDWEST AND LAKES REGION
WEDNESDAY INTO THURSDAY AND WITH IT...SOME VERY COLD AIR. WITH A
DEEP SNOWPACK BY THAT TIME AND DIMINISHING WINDS WEDNESDAY NIGHT
INTO THURSDAY...EXPECT MANY LOCATIONS TO DROP BELOW ZERO FOR LOWS
THURSDAY MORNING. THE AIRMASS MODIFIES/WARMS SOME THURSDAY BUT
STILL EXPECTING LOWS IN THE LOWER SINGLE DIGITS THURSDAY EVENING...
POSSIBLY BELOW ZERO BUT WARM AIR ADVECTION BY MORNING WITH
INCREASING SOUTHERLY WINDS MAY PUT THE BRAKES ON HOW LOW TEMPS FALL
THURSDAY NIGHT. STRONG SOUTHERLY WINDS CONTINUE INTO SATURDAY WITH
WARMING TEMPS...THAT WILL LIKELY BE MUTED SOME BY THE SNOWPACK. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SNOW THROUGH TONIGHT. LIGHT LAKE EFFECT SNOW EARLY MONDAY MAINLY
FOR MDW. PREVAILING VIS AT OR UNDER 1SM THROUGH THIS EVENING.
* NELY WINDS GUSTING TO 30-35 KT LATE THIS AFTERNOON/EARLY
EVENING.
* BLOWING AND DRIFTING SNOW LIKELY THIS AFTERNOON AND TONIGHT.
* PERIODS OF VIS 1/4SM OR LESS THIS AFTERNOON WHEN GUSTS INCREASE
TO 30 KT AND HIGHER.
* IFR-LIFR CIGS THROUGH LATE EVENING.
KMD
//DISCUSSION...UPDATED 18Z...
STEADY SNOWFALL CONTINUES THROUGH THE AFTERNOON AND EVENING. THE
SNOW HAS BEEN WET TO THIS POINT...BUT FROM NORTH TO SOUTH IT WILL
SHIFT TO A DRIER SNOW AS THE AFTERNOON AND EVENING GO ON.
VISIBILITIES HAVE BEEN LARGELY STEADY AROUND 1/2 MILE...AND WHILE
FLUCTUATIONS IN THIS WILL OCCUR FROM TIME TO TIME...EXPECT 1/2 TO
3/4 VSBYS TO GENERALLY BE THE RULE. AS THE WINDS RAMP UP LATER THIS
AFTERNOON AND EVENING...FEEL THAT THERE WILL BE OCCASIONAL 1/4 MILE
VISIBILITIES AS THE SNOW GETS A BIT MORE BLOWABLE...BUT STILL NOT
CONFIDENT IN THIS CONDITION PREVAILING. WILL HAVE TO MONITOR AS THE
WINDS RAMP UP. IF THIS WERE TO OCCUR...IT WOULD BE THE LATE
AFTERNOON AND EARLY EVENING PERIOD WHEN THE SURFACE LOW MOVES A BIT
FARTHER NORTH AND EAST. THINK THAT THE 22Z-02Z TIME FRAME WOULD BE
THE BEST BET FOR THIS. WINDS HOLD IN THE 050 DIRECTION THEN BACK
THROUGH THE EVENING TO 020 BY MID EVENING...THEN NNW OVERNIGHT.
SHOULD SEE SOME SLIGHTY IMPROVEMENT IN VSBY AND DECREASE IN SNOWFALL
FROM 4Z-6Z...AND AFTER 6Z SNOWFALL SHOULD DECREASE SIGNIFICANTLY
THOUGH NOT END...AND WINDS SHOULD START A MORE SIGNIFICANT
DOWNWARD TREND. EXPECT LIGHT LAKE EFFECT SNOW SHOWERS OVERNIGHT.
MOST TERMINALS EXCEPT MDW AND GYY SHOULD BE DRY BY DAYBREAK WITH A
WEAKENING WESTERLY WIND.
KMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE IN WX/VIS TRENDS.
* MEDIUM CONFIDENCE IN CIG TRENDS.
* MEDIUM CONFIDENCE IN TIMING OF IMPROVING CIG/VIS.
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR/WX NIL EARLY. CHANCE SNOW WITH MVFR CIGS/VIS
LATE.
TUESDAY...SLIGHT CHANCE SNOW EARLY WITH MVFR CIGS/VIS. VFR/WX NIL
AFTERNOON. SNOW LIKELY WITH IFR CIG/VIS OVERNIGHT.
WEDNESDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS EARLY. VFR/WX NIL
OVERNIGHT.
THURSDAY...VFR/WX NIL.
FRIDAY...VFR/WX NIL.
SATURDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS POSSIBLE.
KREIN
&&
.MARINE...
315 AM CST
THE SFC LOW OVER THE PLAINS LOOKS TO BE DEEPENING A LITTLE FASTER
AND LOWER WHILE THE HIGH PRESSURE RIDGING OVER THE UPPER GREAT
LAKES IS TRENDING A LITTLE STRONGER. THIS COMBINATION WITH STRONG
COLD ADVECTION SETTING UP OVER THE LAKE TODAY...HAVE EXPANDED THE
GALE WARNING OVER THE ENTIRE OPEN WATERS OF LAKE MICHIGAN AS WELL
AS EXTENDING IN TIME...STARTING A LITTLE EARLIER...AT 15Z THIS
MORNING AND GOING A LITTLE LATER...TO 09Z TONIGHT. ALSO...HAVE
INCREASED GALES TO 40KT OVER THE SOUTHERN PORTIONS OF THE LAKE
WHERE THE PRESSURE GRADIENT AND PRESSURE FALLS ARE STRONGEST. AS
THE WINDS PICK UP TO GALE FORCE AND MUCH COLDER AIR FILTERS OVER
THE LAKE LATER TODAY...HEAVY FREEZING SPRAY WILL BE LIKELY...SO
HAVE ALSO ISSUED A HEAVY FREEZING SPRAY WARNING FROM 15Z THIS
MORNING TO 09Z TONIGHT. THE COLDER AIR WILL SPREAD OVER THE
NORTHERN PORTIONS OF THE LAKE EARLIER THAN THE SOUTHERN
PORTIONS...SO IT IS POSSIBLE THAT THE HEAVY FREEZING SPRAY
POTENTIAL MAY NOT REACH THE SOUTHERN PORTIONS OF THE LAKE UNTIL
THIS AFTERNOON...BUT WENT WITH ONE SEGMENT TO THE WARNING TO
COINCIDE WITH THE GALE WARNING TIMING. THE LOW SHOULD PUSH EAST
INTO THE MID ATLANTIC REGION BE MONDAY AFTERNOON...WHILE HIGH
PRESSURE SPREADS ACROSS THE MISSISSIPPI RIVER INTO THE WESTERN
GREAT LAKES REGION. THIS WILL LEAD TO SUBSIDING WINDS AND
WAVES...ESPECIALLY AS WEAK HIGH PRESSURE PRESSURE CROSSES THE LAKE
MONDAY NIGHT AND TUESDAY.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...LAKESHORE FLOOD ADVISORY...ILZ006-ILZ014 UNTIL 10 AM MONDAY.
BLIZZARD WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022
UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...ILZ023-ILZ032-ILZ033-ILZ039 UNTIL
MIDNIGHT MONDAY.
IN...BLIZZARD WARNING...INZ001 UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...INZ002-INZ010-INZ011-INZ019 UNTIL
MIDNIGHT MONDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1036 AM CST SUN FEB 1 2015
.UPDATE...1031 AM CST
WE HAVE INCREASED SNOWFALL AMOUNTS SOME THIS AFTERNOON...ESPECIALLY
ACROSS NORTHERN ILLINOIS AND FAR NORTHWESTERN INDIANA. A VERY
IMPRESSIVE SYSTEM CONTINUES TO DEVELOP ACROSS THE CENTRAL CONUS THIS
MORNING IN RESPONSE TO A STRONG PV ANOMALY OVER THE CENTRAL PLAINS.
AS THIS STORM CONTINUES TO INTENSIFY THIS AFTERNOON...MODEL GUIDANCE
SUGGESTS THAT A BAND OF STRONG FRONTOGENESIS WILL DEVELOP IN AN
EMERGING DEFORMATION ZONE ASSOCIATED WITH THE 700 MB LOW...RIGHT
ACROSS NORTHERN ILLINOIS. THIS ALSO LOOKS TO OCCUR DURING THE
PERIOD OF BEST STRONG MID/UPPER LEVEL Q-VECTOR DIVERGENCE
ASSOCIATED WITH THE MID/UPPER LEVEL SYSTEM. ALL IN ALL THIS POINTS
TO STRONG DYANAMICS SUPPORTIVE OF PERIODS OF HEAVY SNOW THROUGH
THE DAY TODAY...AND LINGERING THIS EVENING. IT APPEARS THE
HEAVIEST AMOUNTS WILL EXCEED A FOOT IN MANY AREAS...WITH A FOOT
AND A HALF NOT OUT OF THE QUESTION FOR NORTHERN ILLINOIS.
THE OTHER CONCERN IS BLIZZARD CONDITIONS...WE ARE UPGRADING THE REST
OF NORTH CENTRAL ILLINOIS TO A BLIZZARD WARNING. NORTHEASTERLY
WINDS WILL ONLY INCREASE THROUGH THE AFTERNOON...WITH GUSTS
POTENTIAL UP AROUND 40 KT AT TIMES GIVEN THE STRONG GRADIENT SETTING
UP ON THE BACK SIDE OF THIS SYSTEM. THIS HAS ME SERIOUSLY CONCERNED
THAT AS THE SNOW CONTINUES TO BECOME MORE POWDERY THROUGH THE
DAY...THAT WHITE OUT CONDITIONS WILL BE OBSERVED ACROSS NORTHERN
ILLINOIS. THE OTHER CONCERN IS FOR DOWNED TREE BRANCHES AND POWER
LINES. THE SNOW THAT HAS FALLEN THUS FAR ACROSS THE AREA HAS BEEN A
STICKY WET SNOW AND HAS PRODUCED SIGNIFICANT ACCUMULATIONS ON TREES
AND POWER LINES. THE INCREASING WINDS COULD BRING DOWN POWER
LINES...LEADING TO SOME ISOLATED POWER OUTAGES.
NEW UPDATES SHOULD BE OUT SHORTLY.
KJB
&&
.SHORT TERM...
347 AM CST
THROUGH MONDAY...
HAVE BEEN SWAMPED THIS MORNING AND AM RUNNING BEHIND...SO GOING TO
KEEP DISCUSSION BRIEF THIS MORNING AND JUST HIT THE IMPORTANT
CHANGES. THE BIGGEST CHANGES TO GOING FORECAST IS THE UPGRADE TO
A BLIZZARD WARNING FOR PORTIONS OF NE IL/CHICAGO METRO AND TO
LOWER SNOW AMOUNTS AND ADD MIXED PRECIP BACK INTO GRIDS FAR SE
CWA.
GUIDANCE HAS CONTINUED TO TREND NORTH AND STRONGER WITH THE TRACK OF
THIS SYSTEM AND COMPARING GUIDANCE WITH SFC OBS AND BEST SFC
PRESSURE FALLS IT WOULD SEEM TO SUPPORT THE FARTHER NORTH TRACK THAT
THE RAP IN PARTICULAR HAS LATCHED ONTO. THE SOMEWHAT DEEPER LOW
ALONG WITH THE VERY STRONG ARCTIC HIGH SPREADING SOUTHEAST WILL
RESULT IN VERY STRONG WINDS DEVELOPING THIS AFTERNOON. INCREASING
LOW LEVEL COLD AIR ADVECTION AND SFC HEIGHT RISES FAVOR PRETTY GOOD
MIXING IN THE BOUNDARY LAYER...WHICH IS WHAT ALL MODEL FORECAST
SOUNDINGS ARE ADVERTISING. TAKING EVEN THE BEST CASE SCENARIO AND
ONE OF THE WEAKEST MODELS BUFKIT MOMENTUM TRANSFER VALUES SUPPORT
4-7 HOURS OF WIND GUSTS BETWEEN 35-40 MPH LATER THIS AFTERNOON AND
EVENING...WITH MORE AGGRESSIVE GFS/RAP SUPPORTING EVEN STRONGER
WINDS OVER A LONGER DURATION. SNOW HAS BEEN WET THUS FAR BUT WITH
TIME SHOULD SEE THE TRANSITION TOWARD DRIER/MORE BLOWABLE SNOW THIS
AFTERNOON FROM NORTH TO SOUTH AS THE COLUMN COOLS AND THE SNOW
LIQUID CONTENT DECREASES. BIGGEST UNCERTAINTY REVOLVES AROUND
REGARDING UPGRADE TO BLIZZARD WARNING WAS THE SNOW LIQUID CONTENT
AND PROBABILITY AND CONFIDENCE IS CERTAINLY HIGHER THE FARTHER NORTH
FROM I-80 THAT YOU GET...BUT EVEN AS FAR SOUTH AS I-80 FELT FAIRLY
CONFIDENT THAT WHITE OUT CONDITIONS COULD DEVELOP LATE THIS
AFTERNOON AND ESPECIALLY THIS EVENING. FARTHER WEST ACROSS NORTH
CENTRAL ILLINOIS FEEL THAT A BLIZZARD WARNING COULD EASILY BE
JUSTIFIED...BUT IN COORDINATION WITH MKX/DVN HAVE OPTED TO HOLD OFF
FOR NOW AS SNOW INTENSITY COULD BE DECREASING AS WINDS PICK UP.
QUITE POSSIBLE DAY SHIFT MAY NEED TO RE-ACCESS THIS AND AN UPGRADE
TO BLIZZARD WARNING FOR RFD AND POINTS WEST COULD OCCUR ON THE DAY
SHIFT.
OTHER BIG CHANGE TO FORECAST WAS TO ADD SLEET AND THEN DRIZZLE TO
THE FAR SOUTHEAST CWA. SFC TEMPS HAVE BEEN A BIT WARMER AND THE
FARTHER NORTH TRACK OF THE SFC LOW SHOULD KEEP LOW LEVEL WAA GOING
INTO EARLY AFTERNOON WITH AT LEAST THE THREAT OF MIXED
PRECIP...POSSIBLY TRANSITIONING OVER TO JUST DRIZZLE/SNIZZLE AS MID
LEVEL DRY SLOT OVERSPREADS THAT AREA REMOVING ICE NUCLEI FROM THE
CLOUDS LATE THIS AFTERNOON INTO THIS EVENING. THE WETTER SNOW SOUTH
OF I-80 SHOULD RESULT IN LESS SEVERE AND LESS IMPACTFUL
BLOWING/DRIFTING SNOW. GIVEN THE MARGINAL TEMPS AND POTENTIAL MIX
PRECIP HAVE CUT BACK ON ACCUMS IN THE FAR SOUTHEAST COUNTIES OF THE
CWA.
ACCUMULATING LAKE EFFECT POTENTIAL ACTUALLY LOOKS SOMEWHAT LESS
IMPRESSIVE THAN IT DID LAST NIGHT...AND IT WAS ALREADY LOOKING
MARGINAL. SOME SYSTEM SNOWS SHOULD LINGER INTO THIS EVENING BUT LAKE
CONTRIBUTIONS LOOK MINOR WITH LOW INVERSION HEIGHTS AND DECREASING
BOUNDARY LAYER RH AS THE THERMODYNAMICS IMPROVE EVER SO SLIGHTLY.
ANY LAKE ENHANCEMENT TO SNOW TOTALS SHOULD END UP BEING TRIVIAL.
FINALLY...GOING SNOWFALL TOTALS LOOK RIGHT ON TARGET AND MADE VERY
FEW CHANGES OTHER THAN IN SE AS NOTED ABOVE. A RESPECTABLY LARGE
SWATH OF A FOOT OR MORE OF SNOW STILL LOOKS LIKELY AND PROBABLY
CENTERED RELATIVELY CLOSE TO THE I-80 TO I-88/290 CORRIDORS.
ACTUALLY THINKING THAT MAX SNOWFALL TOTALS IN THE CWA COULD END UP
BEING ON THE HIGH END OF THE 10-14 INCH RANGE WITH LOCALIZED TOTALS
POTENTIALLY PUSHING A FOOT AND A HALF IF THE DEFO BAND IS INDEED AS
IMPRESSIVE AS SOME OF THE GUIDANCE WOULD SUGGEST. WHILE SNOWFALL
TOTALS WILL BE VERY IMPRESSIVE OVER MOST OF THE CWA...IT IS
IMPORTANT TO REMEMBER THE BLIZZARD WARNING IS ISSUED NOT FOR
SNOWFALL AMOUNTS BUT RATHER FOR VISIBILITY AND WINDS. THE CRITERIA
FOR BLIZZARD WARNING IS 3+ HOURS OF LESS THAN 1/4SM VSBY IN FALLING
AND/OR BLOWING SNOW ALONG WITH SUSTAINED WINDS OR FREQUENT GUSTS
OVER 35 MPH.
IZZI
&&
.LONG TERM...
MONDAY NIGHT THROUGH SATURDAY...
134 AM...FORECAST CONCERNS INCLUDE A CHANCE OF LIGHT SNOW MONDAY
NIGHT INTO TUESDAY...THEN A BETTER CHANCE FOR ACCUMULATING LIGHT
SNOW TUESDAY NIGHT INTO WEDNESDAY MORNING.
A RIDGE OF HIGH PRESSURE WILL BE MOVING SOUTHEAST OF THE AREA
MONDAY EVENING AS A WEAK WAVE MOVES ACROSS THE REGION MONDAY NIGHT.
FAIRLY LIGHT QPF FROM ALL THE MODELS WITH THIS WAVE BUT PLENTY COLD
ENOUGH FOR THE LOW QPF AMOUNTS TO POTENTIALLY FLUFF UP TO A HALF
INCH MONDAY NIGHT. WHILE TEMPS BY THIS TIME WILL LIKELY BE IN THE
SINGLE DIGITS OR LOW TEENS...CLOUD COVER AND WEAK WARM AIR ADVECTION
MAY ALLOW TEMPS TO HOLD STEADY OR RISE A FEW DEGREES OVERNIGHT.
NEXT WAVE QUICKLY SHIFTS SOUTHEAST ACROSS THE AREA BY TUESDAY
EVENING WITH QPF AMOUNTS BETWEEN ONE AND TWO TENTHS. THIS HAS BEEN
A FAIRLY CONSISTENT FEATURE ON THE MODELS AND IF THIS MATERIALIZES
AS ADVERTISED...A FEW INCHES OF SNOW WILL BE POSSIBLE. TIMING AND
LOCATION ALSO ARE A BIT UNCERTAIN...EARLIER COULD IMPACT THE TUESDAY
EVENING RUSH...LATER COULD IMPACT THE WEDNESDAY MORNING RUSH. BUT
GIVEN THE POTENTIAL FOR SOME ACCUMULATION...OPTED TO BUMP POPS UP TO
LIKELY FOR TUESDAY NIGHT.
HIGH PRESSURE THEN SETTLES SOUTH ACROSS THE MIDWEST AND LAKES REGION
WEDNESDAY INTO THURSDAY AND WITH IT...SOME VERY COLD AIR. WITH A
DEEP SNOWPACK BY THAT TIME AND DIMINISHING WINDS WEDNESDAY NIGHT
INTO THURSDAY...EXPECT MANY LOCATIONS TO DROP BELOW ZERO FOR LOWS
THURSDAY MORNING. THE AIRMASS MODIFIES/WARMS SOME THURSDAY BUT
STILL EXPECTING LOWS IN THE LOWER SINGLE DIGITS THURSDAY EVENING...
POSSIBLY BELOW ZERO BUT WARM AIR ADVECTION BY MORNING WITH
INCREASING SOUTHERLY WINDS MAY PUT THE BRAKES ON HOW LOW TEMPS FALL
THURSDAY NIGHT. STRONG SOUTHERLY WINDS CONTINUE INTO SATURDAY WITH
WARMING TEMPS...THAT WILL LIKELY BE MUTED SOME BY THE SNOWPACK. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SNOW THROUGH TOMORROW MORNING. PREVAILING VIS UNDER 1SM THROUGH
THIS EVENING. VIS ARND 1/2SM THROUGH EARLY EVENING.
* NELY WINDS INCREASING THROUGH THE MORNING...GUSTING TO 30-35KT
THIS AFTERNOON. OCNL HIGHER GUSTS POSSIBLE.
* BLOWING AND DRIFTING SNOW LIKELY THIS AFTERNOON AND TONIGHT.
* PERIODS OF VIS 1/4SM OR LESS THIS AFTERNOON WHEN GUSTS INCREASE
TO 30KT AND HIGHER.
* IFR-LIFR CIGS THROUGH LATE EVENING.
KREIN/KMD
//DISCUSSION...UPDATED 16Z...
SOLID SWATH OF SNOW ACROSS THE TERMINALS THIS MORNING WITH VSBYS
GENERALLY HOLDING AROUND 1/2 MILE. CIGS ARE GENERALLY IN THE
500-900 FT RANGE NORTH OF KARR...300-500 SOUTH WHERE HIGHER
DEWPOINTS EXIST. A BRIEF LET-UP IN SNOW IS POSSIBLE EARLY
AFTERNOON BUT EXPECT THIS WOULD NOT LAST LONG. CONFIDENCE IS NOT
HIGH ENOUGH TO GO PREVAILING 1/4 MILE JUST YET WITH SOME
UNCERTAINTY AS TO SNOWFALL RATES AND HOW FLUFFY THE SNOW WILL BE THIS
AFTERNOON AND ALSO GIVEN THE WET SNOW THAT HAS FALLEN TO THIS POINT...BUT
WINDS WILL INCREASE SIGNIFICANTLY AND WILL HOLD THAT WAY THROUGH
THE EVENING. TRIED TO PEG THE BEST TIME FRAME FOR THIS...BUT THE
TEMPO 1/4 COULD BECOME MORE PREVAILNG...AND MAY LAST LONGER THIS
EVENING IF THE WINDS REACH THE LEVELS THAT THE GFS/GFS LAMP IS
PROGGING.
SHOULD SEE SOME IMPROVEMENT IN VSBY AND DECREASE IN SNOWFALL FROM
3Z-6Z...AND AFTER 6Z SNOWFALL SHOULD DECREASE SIGNIFICANTLY
THOUGH NOT END...AND WINDS SHOULD START A MORE SIGNIFICANT
DOWNWARD TREND.
PREVIOUS DISCUSSION FROM 12Z...
LONG DURATION SNOW EVENT UNDERWAY AS LOW PRESSURE OVER MISSOURI
MOVES EAST THROUGH SOUTHERN ILLINOIS AND INDIANA BY THIS EVENING
AS IT SLOWLY STRENGTHENS. MOISTURE STREAMING NORTH FROM THE GULF
OF MEXICO WILL ALLOW THIS SYSTEM TO PRODUCE MODERATE SNOW THROUGH
THIS EVENING...BEFORE SLOWLY TAPERING OFF LATE TONIGHT INTO EARLY
MONDAY MORNING. VISIBILITIES WILL LIKELY FLUCTUATE WITH HEAVIER
BANDS OF SNOW...BUT PREVAILING VIS LIKELY TO BE AROUND 1/2SM FOR
MUCH OF THE EVENT. AS WINDS STRENGTHEN WITH GUSTS OF 30-35KT...OR
POSSIBLY HIGHER...THIS AFTERNOON AND EARLY EVENING...VIS COULD
DROP TO 1/4SM OR LOWER IN PERIODS OF HEAVIER SNOWFALL AND STRONGER
WIND GUSTS. WINDS WILL TURN MORE NORTHERLY LATE THIS EVENING AND
THEN BEGIN TO DIMINISH EARLY MONDAY MORNING AS HIGH PRESSURE
BUILDS IN FROM THE WEST.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH CONFIDENCE IN WX/VIS TRENDS.
* MEDIUM CONFIDENCE IN CIG TRENDS.
* MEDIUM CONFIDENCE IN TIMING OF IMPROVING CIG/VIS.
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
KREIN/KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR/WX NIL EARLY. CHANCE SNOW WITH MVFR CIGS/VIS
LATE.
TUESDAY...SLIGHT CHANCE SNOW EARLY WITH MVFR CIGS/VIS. VFR/WX NIL
AFTERNOON. SNOW LIKELY WITH IFR CIG/VIS OVERNIGHT.
WEDNESDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS EARLY. VFR/WX NIL
OVERNIGHT.
THURSDAY...VFR/WX NIL.
FRIDAY...VFR/WX NIL.
SATURDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS POSSIBLE.
KREIN
&&
.MARINE...
315 AM CST
THE SFC LOW OVER THE PLAINS LOOKS TO BE DEEPENING A LITTLE FASTER
AND LOWER WHILE THE HIGH PRESSURE RIDGING OVER THE UPPER GREAT
LAKES IS TRENDING A LITTLE STRONGER. THIS COMBINATION WITH STRONG
COLD ADVECTION SETTING UP OVER THE LAKE TODAY...HAVE EXPANDED THE
GALE WARNING OVER THE ENTIRE OPEN WATERS OF LAKE MICHIGAN AS WELL
AS EXTENDING IN TIME...STARTING A LITTLE EARLIER...AT 15Z THIS
MORNING AND GOING A LITTLE LATER...TO 09Z TONIGHT. ALSO...HAVE
INCREASED GALES TO 40KT OVER THE SOUTHERN PORTIONS OF THE LAKE
WHERE THE PRESSURE GRADIENT AND PRESSURE FALLS ARE STRONGEST. AS
THE WINDS PICK UP TO GALE FORCE AND MUCH COLDER AIR FILTERS OVER
THE LAKE LATER TODAY...HEAVY FREEZING SPRAY WILL BE LIKELY...SO
HAVE ALSO ISSUED A HEAVY FREEZING SPRAY WARNING FROM 15Z THIS
MORNING TO 09Z TONIGHT. THE COLDER AIR WILL SPREAD OVER THE
NORTHERN PORTIONS OF THE LAKE EARLIER THAN THE SOUTHERN
PORTIONS...SO IT IS POSSIBLE THAT THE HEAVY FREEZING SPRAY
POTENTIAL MAY NOT REACH THE SOUTHERN PORTIONS OF THE LAKE UNTIL
THIS AFTERNOON...BUT WENT WITH ONE SEGMENT TO THE WARNING TO
COINCIDE WITH THE GALE WARNING TIMING. THE LOW SHOULD PUSH EAST
INTO THE MID ATLANTIC REGION BE MONDAY AFTERNOON...WHILE HIGH
PRESSURE SPREADS ACROSS THE MISSISSIPPI RIVER INTO THE WESTERN
GREAT LAKES REGION. THIS WILL LEAD TO SUBSIDING WINDS AND
WAVES...ESPECIALLY AS WEAK HIGH PRESSURE PRESSURE CROSSES THE LAKE
MONDAY NIGHT AND TUESDAY.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...LAKESHORE FLOOD ADVISORY...ILZ006-ILZ014 UNTIL 10 AM MONDAY.
BLIZZARD WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022
UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...ILZ023-ILZ032-ILZ033-ILZ039 UNTIL
MIDNIGHT MONDAY.
IN...BLIZZARD WARNING...INZ001 UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...INZ002-INZ010-INZ011-INZ019 UNTIL
MIDNIGHT MONDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1031 AM CST SUN FEB 1 2015
.UPDATE...
1031 AM CST
WE HAVE INCREASED SNOWFALL AMOUNTS SOME THIS AFTERNOON...ESPECIALLY
ACROSS NORTHERN ILLINOIS AND FAR NORTHWESTERN INDIANA. A VERY
IMPRESSIVE SYSTEM CONTINUES TO DEVELOP ACROSS THE CENTRAL CONUS THIS
MORNING IN RESPONSE TO A STRONG PV ANOMALY OVER THE CENTRAL PLAINS.
AS THIS STORM CONTINUES TO INTENSIFY THIS AFTERNOON...MODEL GUIDANCE
SUGGESTS THAT THE DEFORMATION ZONE...FEATURING A BAND OF STRONG
FRONTOGENESIS COINCIDENT WITH STRONG MID/UPPER LEVEL Q-VECTOR
DIVERGENCE. ALL IN ALL THIS POINTS TO PERIODS OF HEAVY SNOW THROUGH
THE DAY TODAY...AND LINGERING THIS EVENING. IT APPEARS THE HEAVIEST
AMOUNTS WILL EXCEED A FOOT IN MANY AREAS...WITH A FOOT AND A HALF
NOT OUT OF THE QUESTION FOR NORTHERN ILLINOIS.
THE OTHER CONCERN IS BLIZZARD CONDITIONS...WE ARE UPGRADING THE REST
OF NORTH CENTRAL ILLINOIS TO A BLIZZARD WARNING. NORTHEASTERLY
WINDS WILL ONLY INCREASE THROUGH THE AFTERNOON...WITH GUSTS
POTENTIAL UP AROUND 40 KT AT TIMES GIVEN THE STRONG GRADIENT SETTING
UP ON THE BACK SIDE OF THIS SYSTEM. THIS HAS ME SERIOUSLY CONCERNED
THAT AS THE SNOW CONTINUES TO BECOME MORE POWDERY THROUGH THE
DAY...THAT WHITE OUT CONDITIONS WILL BE OBSERVED ACROSS NORTHERN
ILLINOIS. THE OTHER CONCERN IS FOR DOWNED TREE BRANCHES AND POWER
LINES. THE SNOW THAT HAS FALLEN THUS FAR ACROSS THE AREA HAS BEEN A
STICKY WET SNOW AND HAS PRODUCED SIGNIFICANT ACCUMULATIONS ON TREES
AND POWER LINES. THE INCREASING WINDS COULD BRING DOWN POWER
LINES...LEADING TO SOME ISOLATED POWER OUTAGES.
NEW UPDATES SHOULD BE OUT SHORTLY.
KJB
&&
.SHORT TERM...
347 AM CST
THROUGH MONDAY...
HAVE BEEN SWAMPED THIS MORNING AND AM RUNNING BEHIND...SO GOING TO
KEEP DISCUSSION BRIEF THIS MORNING AND JUST HIT THE IMPORTANT
CHANGES. THE BIGGEST CHANGES TO GOING FORECAST IS THE UPGRADE TO
A BLIZZARD WARNING FOR PORTIONS OF NE IL/CHICAGO METRO AND TO
LOWER SNOW AMOUNTS AND ADD MIXED PRECIP BACK INTO GRIDS FAR SE
CWA.
GUIDANCE HAS CONTINUED TO TREND NORTH AND STRONGER WITH THE TRACK OF
THIS SYSTEM AND COMPARING GUIDANCE WITH SFC OBS AND BEST SFC
PRESSURE FALLS IT WOULD SEEM TO SUPPORT THE FARTHER NORTH TRACK THAT
THE RAP IN PARTICULAR HAS LATCHED ONTO. THE SOMEWHAT DEEPER LOW
ALONG WITH THE VERY STRONG ARCTIC HIGH SPREADING SOUTHEAST WILL
RESULT IN VERY STRONG WINDS DEVELOPING THIS AFTERNOON. INCREASING
LOW LEVEL COLD AIR ADVECTION AND SFC HEIGHT RISES FAVOR PRETTY GOOD
MIXING IN THE BOUNDARY LAYER...WHICH IS WHAT ALL MODEL FORECAST
SOUNDINGS ARE ADVERTISING. TAKING EVEN THE BEST CASE SCENARIO AND
ONE OF THE WEAKEST MODELS BUFKIT MOMENTUM TRANSFER VALUES SUPPORT
4-7 HOURS OF WIND GUSTS BETWEEN 35-40 MPH LATER THIS AFTERNOON AND
EVENING...WITH MORE AGGRESSIVE GFS/RAP SUPPORTING EVEN STRONGER
WINDS OVER A LONGER DURATION. SNOW HAS BEEN WET THUS FAR BUT WITH
TIME SHOULD SEE THE TRANSITION TOWARD DRIER/MORE BLOWABLE SNOW THIS
AFTERNOON FROM NORTH TO SOUTH AS THE COLUMN COOLS AND THE SNOW
LIQUID CONTENT DECREASES. BIGGEST UNCERTAINTY REVOLVES AROUND
REGARDING UPGRADE TO BLIZZARD WARNING WAS THE SNOW LIQUID CONTENT
AND PROBABILITY AND CONFIDENCE IS CERTAINLY HIGHER THE FARTHER NORTH
FROM I-80 THAT YOU GET...BUT EVEN AS FAR SOUTH AS I-80 FELT FAIRLY
CONFIDENT THAT WHITE OUT CONDITIONS COULD DEVELOP LATE THIS
AFTERNOON AND ESPECIALLY THIS EVENING. FARTHER WEST ACROSS NORTH
CENTRAL ILLINOIS FEEL THAT A BLIZZARD WARNING COULD EASILY BE
JUSTIFIED...BUT IN COORDINATION WITH MKX/DVN HAVE OPTED TO HOLD OFF
FOR NOW AS SNOW INTENSITY COULD BE DECREASING AS WINDS PICK UP.
QUITE POSSIBLE DAY SHIFT MAY NEED TO RE-ACCESS THIS AND AN UPGRADE
TO BLIZZARD WARNING FOR RFD AND POINTS WEST COULD OCCUR ON THE DAY
SHIFT.
OTHER BIG CHANGE TO FORECAST WAS TO ADD SLEET AND THEN DRIZZLE TO
THE FAR SOUTHEAST CWA. SFC TEMPS HAVE BEEN A BIT WARMER AND THE
FARTHER NORTH TRACK OF THE SFC LOW SHOULD KEEP LOW LEVEL WAA GOING
INTO EARLY AFTERNOON WITH AT LEAST THE THREAT OF MIXED
PRECIP...POSSIBLY TRANSITIONING OVER TO JUST DRIZZLE/SNIZZLE AS MID
LEVEL DRY SLOT OVERSPREADS THAT AREA REMOVING ICE NUCLEI FROM THE
CLOUDS LATE THIS AFTERNOON INTO THIS EVENING. THE WETTER SNOW SOUTH
OF I-80 SHOULD RESULT IN LESS SEVERE AND LESS IMPACTFUL
BLOWING/DRIFTING SNOW. GIVEN THE MARGINAL TEMPS AND POTENTIAL MIX
PRECIP HAVE CUT BACK ON ACCUMS IN THE FAR SOUTHEAST COUNTIES OF THE
CWA.
ACCUMULATING LAKE EFFECT POTENTIAL ACTUALLY LOOKS SOMEWHAT LESS
IMPRESSIVE THAN IT DID LAST NIGHT...AND IT WAS ALREADY LOOKING
MARGINAL. SOME SYSTEM SNOWS SHOULD LINGER INTO THIS EVENING BUT LAKE
CONTRIBUTIONS LOOK MINOR WITH LOW INVERSION HEIGHTS AND DECREASING
BOUNDARY LAYER RH AS THE THERMODYNAMICS IMPROVE EVER SO SLIGHTLY.
ANY LAKE ENHANCEMENT TO SNOW TOTALS SHOULD END UP BEING TRIVIAL.
FINALLY...GOING SNOWFALL TOTALS LOOK RIGHT ON TARGET AND MADE VERY
FEW CHANGES OTHER THAN IN SE AS NOTED ABOVE. A RESPECTABLY LARGE
SWATH OF A FOOT OR MORE OF SNOW STILL LOOKS LIKELY AND PROBABLY
CENTERED RELATIVELY CLOSE TO THE I-80 TO I-88/290 CORRIDORS.
ACTUALLY THINKING THAT MAX SNOWFALL TOTALS IN THE CWA COULD END UP
BEING ON THE HIGH END OF THE 10-14 INCH RANGE WITH LOCALIZED TOTALS
POTENTIALLY PUSHING A FOOT AND A HALF IF THE DEFO BAND IS INDEED AS
IMPRESSIVE AS SOME OF THE GUIDANCE WOULD SUGGEST. WHILE SNOWFALL
TOTALS WILL BE VERY IMPRESSIVE OVER MOST OF THE CWA...IT IS
IMPORTANT TO REMEMBER THE BLIZZARD WARNING IS ISSUED NOT FOR
SNOWFALL AMOUNTS BUT RATHER FOR VISIBILITY AND WINDS. THE CRITERIA
FOR BLIZZARD WARNING IS 3+ HOURS OF LESS THAN 1/4SM VSBY IN FALLING
AND/OR BLOWING SNOW ALONG WITH SUSTAINED WINDS OR FREQUENT GUSTS
OVER 35 MPH.
IZZI
&&
.LONG TERM...
MONDAY NIGHT THROUGH SATURDAY...
134 AM...FORECAST CONCERNS INCLUDE A CHANCE OF LIGHT SNOW MONDAY
NIGHT INTO TUESDAY...THEN A BETTER CHANCE FOR ACCUMULATING LIGHT
SNOW TUESDAY NIGHT INTO WEDNESDAY MORNING.
A RIDGE OF HIGH PRESSURE WILL BE MOVING SOUTHEAST OF THE AREA
MONDAY EVENING AS A WEAK WAVE MOVES ACROSS THE REGION MONDAY NIGHT.
FAIRLY LIGHT QPF FROM ALL THE MODELS WITH THIS WAVE BUT PLENTY COLD
ENOUGH FOR THE LOW QPF AMOUNTS TO POTENTIALLY FLUFF UP TO A HALF
INCH MONDAY NIGHT. WHILE TEMPS BY THIS TIME WILL LIKELY BE IN THE
SINGLE DIGITS OR LOW TEENS...CLOUD COVER AND WEAK WARM AIR ADVECTION
MAY ALLOW TEMPS TO HOLD STEADY OR RISE A FEW DEGREES OVERNIGHT.
NEXT WAVE QUICKLY SHIFTS SOUTHEAST ACROSS THE AREA BY TUESDAY
EVENING WITH QPF AMOUNTS BETWEEN ONE AND TWO TENTHS. THIS HAS BEEN
A FAIRLY CONSISTENT FEATURE ON THE MODELS AND IF THIS MATERIALIZES
AS ADVERTISED...A FEW INCHES OF SNOW WILL BE POSSIBLE. TIMING AND
LOCATION ALSO ARE A BIT UNCERTAIN...EARLIER COULD IMPACT THE TUESDAY
EVENING RUSH...LATER COULD IMPACT THE WEDNESDAY MORNING RUSH. BUT
GIVEN THE POTENTIAL FOR SOME ACCUMULATION...OPTED TO BUMP POPS UP TO
LIKELY FOR TUESDAY NIGHT.
HIGH PRESSURE THEN SETTLES SOUTH ACROSS THE MIDWEST AND LAKES REGION
WEDNESDAY INTO THURSDAY AND WITH IT...SOME VERY COLD AIR. WITH A
DEEP SNOWPACK BY THAT TIME AND DIMINISHING WINDS WEDNESDAY NIGHT
INTO THURSDAY...EXPECT MANY LOCATIONS TO DROP BELOW ZERO FOR LOWS
THURSDAY MORNING. THE AIRMASS MODIFIES/WARMS SOME THURSDAY BUT
STILL EXPECTING LOWS IN THE LOWER SINGLE DIGITS THURSDAY EVENING...
POSSIBLY BELOW ZERO BUT WARM AIR ADVECTION BY MORNING WITH
INCREASING SOUTHERLY WINDS MAY PUT THE BRAKES ON HOW LOW TEMPS FALL
THURSDAY NIGHT. STRONG SOUTHERLY WINDS CONTINUE INTO SATURDAY WITH
WARMING TEMPS...THAT WILL LIKELY BE MUTED SOME BY THE SNOWPACK. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SNOW THROUGH TOMORROW MORNING. PREVAILING VIS UNDER 1SM THROUGH
THIS EVENING. VIS ARND 1/2SM THROUGH EARLY EVENING.
* NELY WINDS INCREASING THROUGH THE MORNING...GUSTING TO 30-35KT
THIS AFTERNOON. OCNL HIGHER GUSTS POSSIBLE.
* BLOWING AND DRIFTING SNOW LIKELY THIS AFTERNOON AND TONIGHT.
* PERIODS OF VIS 1/4SM OR LESS THIS AFTERNOON WHEN GUSTS INCREASE
TO 30KT AND HIGHER.
* IFR-LIFR CIGS THROUGH LATE EVENING.
KREIN/KMD
//DISCUSSION...UPDATED 16Z...
SOLID SWATH OF SNOW ACROSS THE TERMINALS THIS MORNING WITH VSBYS
GENERALLY HOLDING AROUND 1/2 MILE. CIGS ARE GENERALLY IN THE
500-900 FT RANGE NORTH OF KARR...300-500 SOUTH WHERE HIGHER
DEWPOINTS EXIST. A BRIEF LET-UP IN SNOW IS POSSIBLE EARLY
AFTERNOON BUT EXPECT THIS WOULD NOT LAST LONG. CONFIDENCE IS NOT
HIGH ENOUGH TO GO PREVAILING 1/4 MILE JUST YET WITH SOME
UNCERTAINTY AS TO SNOWFALL RATES AND HOW FLUFFY THE SNOW WILL BE THIS
AFTERNOON AND ALSO GIVEN THE WET SNOW THAT HAS FALLEN TO THIS POINT...BUT
WINDS WILL INCREASE SIGNIFICANTLY AND WILL HOLD THAT WAY THROUGH
THE EVENING. TRIED TO PEG THE BEST TIME FRAME FOR THIS...BUT THE
TEMPO 1/4 COULD BECOME MORE PREVAILNG...AND MAY LAST LONGER THIS
EVENING IF THE WINDS REACH THE LEVELS THAT THE GFS/GFS LAMP IS
PROGGING.
SHOULD SEE SOME IMPROVEMENT IN VSBY AND DECREASE IN SNOWFALL FROM
3Z-6Z...AND AFTER 6Z SNOWFALL SHOULD DECREASE SIGNIFICANTLY
THOUGH NOT END...AND WINDS SHOULD START A MORE SIGNIFICANT
DOWNWARD TREND.
PREVIOUS DISCUSSION FROM 12Z...
LONG DURATION SNOW EVENT UNDERWAY AS LOW PRESSURE OVER MISSOURI
MOVES EAST THROUGH SOUTHERN ILLINOIS AND INDIANA BY THIS EVENING
AS IT SLOWLY STRENGTHENS. MOISTURE STREAMING NORTH FROM THE GULF
OF MEXICO WILL ALLOW THIS SYSTEM TO PRODUCE MODERATE SNOW THROUGH
THIS EVENING...BEFORE SLOWLY TAPERING OFF LATE TONIGHT INTO EARLY
MONDAY MORNING. VISIBILITIES WILL LIKELY FLUCTUATE WITH HEAVIER
BANDS OF SNOW...BUT PREVAILING VIS LIKELY TO BE AROUND 1/2SM FOR
MUCH OF THE EVENT. AS WINDS STRENGTHEN WITH GUSTS OF 30-35KT...OR
POSSIBLY HIGHER...THIS AFTERNOON AND EARLY EVENING...VIS COULD
DROP TO 1/4SM OR LOWER IN PERIODS OF HEAVIER SNOWFALL AND STRONGER
WIND GUSTS. WINDS WILL TURN MORE NORTHERLY LATE THIS EVENING AND
THEN BEGIN TO DIMINISH EARLY MONDAY MORNING AS HIGH PRESSURE
BUILDS IN FROM THE WEST.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH CONFIDENCE IN WX/VIS TRENDS.
* MEDIUM CONFIDENCE IN CIG TRENDS.
* MEDIUM CONFIDENCE IN TIMING OF IMPROVING CIG/VIS.
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
KREIN/KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR/WX NIL EARLY. CHANCE SNOW WITH MVFR CIGS/VIS
LATE.
TUESDAY...SLIGHT CHANCE SNOW EARLY WITH MVFR CIGS/VIS. VFR/WX NIL
AFTERNOON. SNOW LIKELY WITH IFR CIG/VIS OVERNIGHT.
WEDNESDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS EARLY. VFR/WX NIL
OVERNIGHT.
THURSDAY...VFR/WX NIL.
FRIDAY...VFR/WX NIL.
SATURDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS POSSIBLE.
KREIN
&&
.MARINE...
315 AM CST
THE SFC LOW OVER THE PLAINS LOOKS TO BE DEEPENING A LITTLE FASTER
AND LOWER WHILE THE HIGH PRESSURE RIDGING OVER THE UPPER GREAT
LAKES IS TRENDING A LITTLE STRONGER. THIS COMBINATION WITH STRONG
COLD ADVECTION SETTING UP OVER THE LAKE TODAY...HAVE EXPANDED THE
GALE WARNING OVER THE ENTIRE OPEN WATERS OF LAKE MICHIGAN AS WELL
AS EXTENDING IN TIME...STARTING A LITTLE EARLIER...AT 15Z THIS
MORNING AND GOING A LITTLE LATER...TO 09Z TONIGHT. ALSO...HAVE
INCREASED GALES TO 40KT OVER THE SOUTHERN PORTIONS OF THE LAKE
WHERE THE PRESSURE GRADIENT AND PRESSURE FALLS ARE STRONGEST. AS
THE WINDS PICK UP TO GALE FORCE AND MUCH COLDER AIR FILTERS OVER
THE LAKE LATER TODAY...HEAVY FREEZING SPRAY WILL BE LIKELY...SO
HAVE ALSO ISSUED A HEAVY FREEZING SPRAY WARNING FROM 15Z THIS
MORNING TO 09Z TONIGHT. THE COLDER AIR WILL SPREAD OVER THE
NORTHERN PORTIONS OF THE LAKE EARLIER THAN THE SOUTHERN
PORTIONS...SO IT IS POSSIBLE THAT THE HEAVY FREEZING SPRAY
POTENTIAL MAY NOT REACH THE SOUTHERN PORTIONS OF THE LAKE UNTIL
THIS AFTERNOON...BUT WENT WITH ONE SEGMENT TO THE WARNING TO
COINCIDE WITH THE GALE WARNING TIMING. THE LOW SHOULD PUSH EAST
INTO THE MID ATLANTIC REGION BE MONDAY AFTERNOON...WHILE HIGH
PRESSURE SPREADS ACROSS THE MISSISSIPPI RIVER INTO THE WESTERN
GREAT LAKES REGION. THIS WILL LEAD TO SUBSIDING WINDS AND
WAVES...ESPECIALLY AS WEAK HIGH PRESSURE PRESSURE CROSSES THE LAKE
MONDAY NIGHT AND TUESDAY.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...LAKESHORE FLOOD ADVISORY...ILZ006-ILZ014 UNTIL 10 AM MONDAY.
BLIZZARD WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022
UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...ILZ023-ILZ032-ILZ033-ILZ039 UNTIL
MIDNIGHT MONDAY.
IN...BLIZZARD WARNING...INZ001 UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...INZ002-INZ010-INZ011-INZ019 UNTIL
MIDNIGHT MONDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1025 AM CST SUN FEB 1 2015
.SHORT TERM...
347 AM CST
THROUGH MONDAY...
HAVE BEEN SWAMPED THIS MORNING AND AM RUNNING BEHIND...SO GOING TO
KEEP DISCUSSION BRIEF THIS MORNING AND JUST HIT THE IMPORTANT
CHANGES. THE BIGGEST CHANGES TO GOING FORECAST IS THE UPGRADE TO
A BLIZZARD WARNING FOR PORTIONS OF NE IL/CHICAGO METRO AND TO
LOWER SNOW AMOUNTS AND ADD MIXED PRECIP BACK INTO GRIDS FAR SE
CWA.
GUIDANCE HAS CONTINUED TO TREND NORTH AND STRONGER WITH THE TRACK OF
THIS SYSTEM AND COMPARING GUIDANCE WITH SFC OBS AND BEST SFC
PRESSURE FALLS IT WOULD SEEM TO SUPPORT THE FARTHER NORTH TRACK THAT
THE RAP IN PARTICULAR HAS LATCHED ONTO. THE SOMEWHAT DEEPER LOW
ALONG WITH THE VERY STRONG ARCTIC HIGH SPREADING SOUTHEAST WILL
RESULT IN VERY STRONG WINDS DEVELOPING THIS AFTERNOON. INCREASING
LOW LEVEL COLD AIR ADVECTION AND SFC HEIGHT RISES FAVOR PRETTY GOOD
MIXING IN THE BOUNDARY LAYER...WHICH IS WHAT ALL MODEL FORECAST
SOUNDINGS ARE ADVERTISING. TAKING EVEN THE BEST CASE SCENARIO AND
ONE OF THE WEAKEST MODELS BUFKIT MOMENTUM TRANSFER VALUES SUPPORT
4-7 HOURS OF WIND GUSTS BETWEEN 35-40 MPH LATER THIS AFTERNOON AND
EVENING...WITH MORE AGGRESSIVE GFS/RAP SUPPORTING EVEN STRONGER
WINDS OVER A LONGER DURATION. SNOW HAS BEEN WET THUS FAR BUT WITH
TIME SHOULD SEE THE TRANSITION TOWARD DRIER/MORE BLOWABLE SNOW THIS
AFTERNOON FROM NORTH TO SOUTH AS THE COLUMN COOLS AND THE SNOW
LIQUID CONTENT DECREASES. BIGGEST UNCERTAINTY REVOLVES AROUND
REGARDING UPGRADE TO BLIZZARD WARNING WAS THE SNOW LIQUID CONTENT
AND PROBABILITY AND CONFIDENCE IS CERTAINLY HIGHER THE FARTHER NORTH
FROM I-80 THAT YOU GET...BUT EVEN AS FAR SOUTH AS I-80 FELT FAIRLY
CONFIDENT THAT WHITE OUT CONDITIONS COULD DEVELOP LATE THIS
AFTERNOON AND ESPECIALLY THIS EVENING. FARTHER WEST ACROSS NORTH
CENTRAL ILLINOIS FEEL THAT A BLIZZARD WARNING COULD EASILY BE
JUSTIFIED...BUT IN COORDINATION WITH MKX/DVN HAVE OPTED TO HOLD OFF
FOR NOW AS SNOW INTENSITY COULD BE DECREASING AS WINDS PICK UP.
QUITE POSSIBLE DAY SHIFT MAY NEED TO RE-ACCESS THIS AND AN UPGRADE
TO BLIZZARD WARNING FOR RFD AND POINTS WEST COULD OCCUR ON THE DAY
SHIFT.
OTHER BIG CHANGE TO FORECAST WAS TO ADD SLEET AND THEN DRIZZLE TO
THE FAR SOUTHEAST CWA. SFC TEMPS HAVE BEEN A BIT WARMER AND THE
FARTHER NORTH TRACK OF THE SFC LOW SHOULD KEEP LOW LEVEL WAA GOING
INTO EARLY AFTERNOON WITH AT LEAST THE THREAT OF MIXED
PRECIP...POSSIBLY TRANSITIONING OVER TO JUST DRIZZLE/SNIZZLE AS MID
LEVEL DRY SLOT OVERSPREADS THAT AREA REMOVING ICE NUCLEI FROM THE
CLOUDS LATE THIS AFTERNOON INTO THIS EVENING. THE WETTER SNOW SOUTH
OF I-80 SHOULD RESULT IN LESS SEVERE AND LESS IMPACTFUL
BLOWING/DRIFTING SNOW. GIVEN THE MARGINAL TEMPS AND POTENTIAL MIX
PRECIP HAVE CUT BACK ON ACCUMS IN THE FAR SOUTHEAST COUNTIES OF THE
CWA.
ACCUMULATING LAKE EFFECT POTENTIAL ACTUALLY LOOKS SOMEWHAT LESS
IMPRESSIVE THAN IT DID LAST NIGHT...AND IT WAS ALREADY LOOKING
MARGINAL. SOME SYSTEM SNOWS SHOULD LINGER INTO THIS EVENING BUT LAKE
CONTRIBUTIONS LOOK MINOR WITH LOW INVERSION HEIGHTS AND DECREASING
BOUNDARY LAYER RH AS THE THERMODYNAMICS IMPROVE EVER SO SLIGHTLY.
ANY LAKE ENHANCEMENT TO SNOW TOTALS SHOULD END UP BEING TRIVIAL.
FINALLY...GOING SNOWFALL TOTALS LOOK RIGHT ON TARGET AND MADE VERY
FEW CHANGES OTHER THAN IN SE AS NOTED ABOVE. A RESPECTABLY LARGE
SWATH OF A FOOT OR MORE OF SNOW STILL LOOKS LIKELY AND PROBABLY
CENTERED RELATIVELY CLOSE TO THE I-80 TO I-88/290 CORRIDORS.
ACTUALLY THINKING THAT MAX SNOWFALL TOTALS IN THE CWA COULD END UP
BEING ON THE HIGH END OF THE 10-14 INCH RANGE WITH LOCALIZED TOTALS
POTENTIALLY PUSHING A FOOT AND A HALF IF THE DEFO BAND IS INDEED AS
IMPRESSIVE AS SOME OF THE GUIDANCE WOULD SUGGEST. WHILE SNOWFALL
TOTALS WILL BE VERY IMPRESSIVE OVER MOST OF THE CWA...IT IS
IMPORTANT TO REMEMBER THE BLIZZARD WARNING IS ISSUED NOT FOR
SNOWFALL AMOUNTS BUT RATHER FOR VISIBILITY AND WINDS. THE CRITERIA
FOR BLIZZARD WARNING IS 3+ HOURS OF LESS THAN 1/4SM VSBY IN FALLING
AND/OR BLOWING SNOW ALONG WITH SUSTAINED WINDS OR FREQUENT GUSTS
OVER 35 MPH.
IZZI
&&
.LONG TERM...
MONDAY NIGHT THROUGH SATURDAY...
134 AM...FORECAST CONCERNS INCLUDE A CHANCE OF LIGHT SNOW MONDAY
NIGHT INTO TUESDAY...THEN A BETTER CHANCE FOR ACCUMULATING LIGHT
SNOW TUESDAY NIGHT INTO WEDNESDAY MORNING.
A RIDGE OF HIGH PRESSURE WILL BE MOVING SOUTHEAST OF THE AREA
MONDAY EVENING AS A WEAK WAVE MOVES ACROSS THE REGION MONDAY NIGHT.
FAIRLY LIGHT QPF FROM ALL THE MODELS WITH THIS WAVE BUT PLENTY COLD
ENOUGH FOR THE LOW QPF AMOUNTS TO POTENTIALLY FLUFF UP TO A HALF
INCH MONDAY NIGHT. WHILE TEMPS BY THIS TIME WILL LIKELY BE IN THE
SINGLE DIGITS OR LOW TEENS...CLOUD COVER AND WEAK WARM AIR ADVECTION
MAY ALLOW TEMPS TO HOLD STEADY OR RISE A FEW DEGREES OVERNIGHT.
NEXT WAVE QUICKLY SHIFTS SOUTHEAST ACROSS THE AREA BY TUESDAY
EVENING WITH QPF AMOUNTS BETWEEN ONE AND TWO TENTHS. THIS HAS BEEN
A FAIRLY CONSISTENT FEATURE ON THE MODELS AND IF THIS MATERIALIZES
AS ADVERTISED...A FEW INCHES OF SNOW WILL BE POSSIBLE. TIMING AND
LOCATION ALSO ARE A BIT UNCERTAIN...EARLIER COULD IMPACT THE TUESDAY
EVENING RUSH...LATER COULD IMPACT THE WEDNESDAY MORNING RUSH. BUT
GIVEN THE POTENTIAL FOR SOME ACCUMULATION...OPTED TO BUMP POPS UP TO
LIKELY FOR TUESDAY NIGHT.
HIGH PRESSURE THEN SETTLES SOUTH ACROSS THE MIDWEST AND LAKES REGION
WEDNESDAY INTO THURSDAY AND WITH IT...SOME VERY COLD AIR. WITH A
DEEP SNOWPACK BY THAT TIME AND DIMINISHING WINDS WEDNESDAY NIGHT
INTO THURSDAY...EXPECT MANY LOCATIONS TO DROP BELOW ZERO FOR LOWS
THURSDAY MORNING. THE AIRMASS MODIFIES/WARMS SOME THURSDAY BUT
STILL EXPECTING LOWS IN THE LOWER SINGLE DIGITS THURSDAY EVENING...
POSSIBLY BELOW ZERO BUT WARM AIR ADVECTION BY MORNING WITH
INCREASING SOUTHERLY WINDS MAY PUT THE BRAKES ON HOW LOW TEMPS FALL
THURSDAY NIGHT. STRONG SOUTHERLY WINDS CONTINUE INTO SATURDAY WITH
WARMING TEMPS...THAT WILL LIKELY BE MUTED SOME BY THE SNOWPACK. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SNOW THROUGH TOMORROW MORNING. PREVAILING VIS UNDER 1SM THROUGH
THIS EVENING. VIS ARND 1/2SM THROUGH EARLY EVENING.
* NELY WINDS INCREASING THROUGH THE MORNING...GUSTING TO 30-35KT
THIS AFTERNOON. OCNL HIGHER GUSTS POSSIBLE.
* BLOWING AND DRIFTING SNOW LIKELY THIS AFTERNOON AND TONIGHT.
* PERIODS OF VIS 1/4SM OR LESS THIS AFTERNOON WHEN GUSTS INCREASE
TO 30KT AND HIGHER.
* IFR-LIFR CIGS THROUGH LATE EVENING.
KREIN/KMD
//DISCUSSION...UPDATED 16Z...
SOLID SWATH OF SNOW ACROSS THE TERMINALS THIS MORNING WITH VSBYS
GENERALLY HOLDING AROUND 1/2 MILE. CIGS ARE GENERALLY IN THE
500-900 FT RANGE NORTH OF KARR...300-500 SOUTH WHERE HIGHER
DEWPOINTS EXIST. A BRIEF LET-UP IN SNOW IS POSSIBLE EARLY
AFTERNOON BUT EXPECT THIS WOULD NOT LAST LONG. CONFIDENCE IS NOT
HIGH ENOUGH TO GO PREVAILING 1/4 MILE JUST YET WITH SOME
UNCERTAINTY AS TO SNOWFALL RATES AND HOW FLUFFY THE SNOW WILL BE THIS
AFTERNOON AND ALSO GIVEN THE WET SNOW THAT HAS FALLEN TO THIS POINT...BUT
WINDS WILL INCREASE SIGNIFICANTLY AND WILL HOLD THAT WAY THROUGH
THE EVENING. TRIED TO PEG THE BEST TIME FRAME FOR THIS...BUT THE
TEMPO 1/4 COULD BECOME MORE PREVAILNG...AND MAY LAST LONGER THIS
EVENING IF THE WINDS REACH THE LEVELS THAT THE GFS/GFS LAMP IS
PROGGING.
SHOULD SEE SOME IMPROVEMENT IN VSBY AND DECREASE IN SNOWFALL FROM
3Z-6Z...AND AFTER 6Z SNOWFALL SHOULD DECREASE SIGNIFICANTLY
THOUGH NOT END...AND WINDS SHOULD START A MORE SIGNIFICANT
DOWNWARD TREND.
PREVIOUS DISCUSSION FROM 12Z...
LONG DURATION SNOW EVENT UNDERWAY AS LOW PRESSURE OVER MISSOURI
MOVES EAST THROUGH SOUTHERN ILLINOIS AND INDIANA BY THIS EVENING
AS IT SLOWLY STRENGTHENS. MOISTURE STREAMING NORTH FROM THE GULF
OF MEXICO WILL ALLOW THIS SYSTEM TO PRODUCE MODERATE SNOW THROUGH
THIS EVENING...BEFORE SLOWLY TAPERING OFF LATE TONIGHT INTO EARLY
MONDAY MORNING. VISIBILITIES WILL LIKELY FLUCTUATE WITH HEAVIER
BANDS OF SNOW...BUT PREVAILING VIS LIKELY TO BE AROUND 1/2SM FOR
MUCH OF THE EVENT. AS WINDS STRENGTHEN WITH GUSTS OF 30-35KT...OR
POSSIBLY HIGHER...THIS AFTERNOON AND EARLY EVENING...VIS COULD
DROP TO 1/4SM OR LOWER IN PERIODS OF HEAVIER SNOWFALL AND STRONGER
WIND GUSTS. WINDS WILL TURN MORE NORTHERLY LATE THIS EVENING AND
THEN BEGIN TO DIMINISH EARLY MONDAY MORNING AS HIGH PRESSURE
BUILDS IN FROM THE WEST.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH CONFIDENCE IN WX/VIS TRENDS.
* MEDIUM CONFIDENCE IN CIG TRENDS.
* MEDIUM CONFIDENCE IN TIMING OF IMPROVING CIG/VIS.
* MEDIUM TO HIGH CONFIDENCE IN WIND TRENDS.
KREIN/KMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR/WX NIL EARLY. CHANCE SNOW WITH MVFR CIGS/VIS
LATE.
TUESDAY...SLIGHT CHANCE SNOW EARLY WITH MVFR CIGS/VIS. VFR/WX NIL
AFTERNOON. SNOW LIKELY WITH IFR CIG/VIS OVERNIGHT.
WEDNESDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS EARLY. VFR/WX NIL
OVERNIGHT.
THURSDAY...VFR/WX NIL.
FRIDAY...VFR/WX NIL.
SATURDAY...SLIGHT CHANCE SNOW WITH MVFR CIG/VIS POSSIBLE.
KREIN
&&
.MARINE...
315 AM CST
THE SFC LOW OVER THE PLAINS LOOKS TO BE DEEPENING A LITTLE FASTER
AND LOWER WHILE THE HIGH PRESSURE RIDGING OVER THE UPPER GREAT
LAKES IS TRENDING A LITTLE STRONGER. THIS COMBINATION WITH STRONG
COLD ADVECTION SETTING UP OVER THE LAKE TODAY...HAVE EXPANDED THE
GALE WARNING OVER THE ENTIRE OPEN WATERS OF LAKE MICHIGAN AS WELL
AS EXTENDING IN TIME...STARTING A LITTLE EARLIER...AT 15Z THIS
MORNING AND GOING A LITTLE LATER...TO 09Z TONIGHT. ALSO...HAVE
INCREASED GALES TO 40KT OVER THE SOUTHERN PORTIONS OF THE LAKE
WHERE THE PRESSURE GRADIENT AND PRESSURE FALLS ARE STRONGEST. AS
THE WINDS PICK UP TO GALE FORCE AND MUCH COLDER AIR FILTERS OVER
THE LAKE LATER TODAY...HEAVY FREEZING SPRAY WILL BE LIKELY...SO
HAVE ALSO ISSUED A HEAVY FREEZING SPRAY WARNING FROM 15Z THIS
MORNING TO 09Z TONIGHT. THE COLDER AIR WILL SPREAD OVER THE
NORTHERN PORTIONS OF THE LAKE EARLIER THAN THE SOUTHERN
PORTIONS...SO IT IS POSSIBLE THAT THE HEAVY FREEZING SPRAY
POTENTIAL MAY NOT REACH THE SOUTHERN PORTIONS OF THE LAKE UNTIL
THIS AFTERNOON...BUT WENT WITH ONE SEGMENT TO THE WARNING TO
COINCIDE WITH THE GALE WARNING TIMING. THE LOW SHOULD PUSH EAST
INTO THE MID ATLANTIC REGION BE MONDAY AFTERNOON...WHILE HIGH
PRESSURE SPREADS ACROSS THE MISSISSIPPI RIVER INTO THE WESTERN
GREAT LAKES REGION. THIS WILL LEAD TO SUBSIDING WINDS AND
WAVES...ESPECIALLY AS WEAK HIGH PRESSURE PRESSURE CROSSES THE LAKE
MONDAY NIGHT AND TUESDAY.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...LAKESHORE FLOOD ADVISORY...ILZ006-ILZ014 UNTIL 10 AM MONDAY.
BLIZZARD WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022
UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...ILZ023-ILZ032-ILZ033-ILZ039 UNTIL
MIDNIGHT MONDAY.
IN...BLIZZARD WARNING...INZ001 UNTIL MIDNIGHT MONDAY.
WINTER STORM WARNING...INZ002-INZ010-INZ011-INZ019 UNTIL
MIDNIGHT MONDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-LMZ742-
LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364-
LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-
LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-
LMZ868-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 3 AM MONDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
359 PM CST SUN FEB 1 2015
.DISCUSSION...
THE SCT CONVECTION HAS RAPIDLY MOVED E ACROSS LOWER E TX/NCNTRL LA
THIS AFTERNOON ALONG THE COLD FRONT...WHICH EXTENDS FROM THE MS RIVER
ALONG THE AR/MS BORDER SW TO LLQ...TO ELD...TO JUST N OF A IER...TO S
OF A LFK LINE AS OF 21Z. THE HRRR CONTINUES TO HAVE THE BEST HANDLE ON
THE ONGOING CONVECTION...WHICH SHOULD COMPLETELY EXIT THE AREA
BY/SHORTLY AFTER 00Z. BEHIND THE FRONT...GUSTY NW WINDS CONTINUE TO
EXPAND SE...WITH GUSTS TO 25KTS COMMON ACROSS EXTREME NE TX/SE OK/SW
AR. THE SHORT TERM PROGS DO AGREE ON A 6MB PRESSURE DIFFERENCE FROM W
TO E ACROSS THE CWA THIS EVENING...AND GIVEN THIS...HAVE EXPANDED THE
LAKE WIND ADVISORY THROUGH 10Z MONDAY TO COVER THE REMAINDER OF THE
CWA EXCEPT THE LOWER SAM RAYBURN COUNTRY OF DEEP E TX AS WELL AS THE
SRN PARISHES OF NCNTRL LA...WHERE WINDS SHOULD BE A BIT MORE MARGINAL.
STRONG COLD ADVECTION BEHIND THE FRONT SHOULD RESULT IN FREEZING TEMPS
OVER ALL BUT THE SRN AND ERN SECTIONS OF THE REGION...DESPITE THE
POST-FRONTAL STRATOCU OVER CNTRL/ERN OK NOT CLEARING UNTIL LATE
TONIGHT ACROSS SE OK/SW AR/NCNTRL LA.
CANADIAN SFC RIDGING WILL BEGIN TO SETTLE S ACROSS THE SRN PLAINS
MONDAY...THUS WEAKENING THE GRADIENT BY DAYBREAK. HOWEVER...EVEN WITH
ABUNDANT SUNSHINE...TEMPS WILL STRUGGLE TO CLIMB MUCH INTO THE
40S...STILL SOME 10-15 DEGREES BELOW NORMAL. WINDS SHOULD MOSTLY
DECOUPLE BY MONDAY NIGHT AS THE SFC RIDGE MOVES OVER THE REGION...BUT
SHOULD START TO SEE AN INCREASE IN CIRRUS LATE AS THE CLOSED LOW OVER
SRN BAJA THIS AFTERNOON...BEGINS TO NUDGE E INTO NW OLD MX MONDAY
NIGHT AND INTO S TX BY WEDNESDAY MORNING. THE INCREASED CIRRUS MAY
HELP OFFSET THE MORE IDEAL RADIATIONAL COOLING THAT WOULD NORMALLY
TAKE PLACE...BUT STILL EXPECTING MUCH OF THE AREA TO SEE SEVERAL HOURS
OF SUBFREEZING TEMPS. THE PROGS HAVE REMAINED FAIRLY CONSISTENT WITH
THE TRACK OF THIS LOW THE LAST 24 HOURS...WITH THE ELEVATED MOISTURE
INCREASING BY TUESDAY AFTERNOON...WITH AREAS OF -RA DEVELOPING MAINLY
OVER E TX/N LA. THE PROGS HAVE BACKED OFF CONSIDERABLY ON QPF WITH
THIS SYSTEM AS IT BEGINS TO OPEN UP AND ACCELERATE E ACROSS S LA
WEDNESDAY...WITH THE BEST FORCING MAINLY FOCUSED ALONG THE EXTREME SE
TX/SRN LA COASTS. HAVE LOWERED POPS TO LOW CHANCE TUESDAY NIGHT AND
WEDNESDAY FOR AREAS ALONG/S OF I-20...BEFORE THE NEXT SHORTWAVE
CLIPPER ROUNDS THE GREAT LAKES REGION WEDNESDAY AFTERNOON. THIS NEXT
SHORTWAVE SHOULD ALLOW FOR ANOTHER COLD FRONT TO NUDGE S WEDNESDAY
NIGHT/THURSDAY MORNING...DRIVING TEMPS BACK DOWN TO SOME 10 DEGREES
BELOW NORMAL ONCE AGAIN. CAN/T RULE OUT ISOLATED AREAS OF -RA
DEVELOPING NEAR/BEHIND THE FROPA...BUT THE MOISTURE PROFILE WILL
REMAIN SHALLOW WHILE THE BEST FORCING WILL BE NE OF THE AREA.
SHOULD AGAIN BEGIN TO SEE A MODERATION OF TEMPS BY FRIDAY AND
ESPECIALLY NEXT WEEKEND...AS TEMPS RETURN BACK ABOVE NORMAL. DRY
CONDITIONS SHOULD PERSIST THROUGH NEXT WEEKEND AS WELL.
PRELIMS TO FOLLOW BELOW...
15
&&
.PREV DISCUSSION... /ISSUED 1229 PM CST SUN FEB 1 2015/
AVIATION...
LOW CIGS THIS MORNING HAVE LIFTED TO MOSTLY MVFR LVLS ACROSS THE
AREA. A STG COLD FRONT JUST REACHING THE KTYR AND KTXK TERMINALS.
WSHFT ALONG FRONT TO INCREASE NW 15 KTS...WITH GUSTS OVER 25 KTS
INTO NE TX/SE OK. NARROW BAND OF HEAVY SHOWERS...CURRENTLY NEAR
KSHV AND KELD...JUST AHEAD OF FRONT. ISOLD TSTMS POSSIBLE...MAINLY
SOUTH OF I-20 AS PREFRONTAL TEMPS WARM INTO UPPER 60S TO LOWER 70S.
PREFRONTAL WINDS S-SW 10 TO 15 KTS. SKIES BECMG VFR SKC FROM THE
WEST BEGINNING AROUND 02/00Z. GUSTY NW WINDS TO CONTINUE UNTIL
AROUND 02/06Z...THEN BECMG NORTHERLY AT 5 TO 10 KTS THRU REMAINDER
OF FCST PERIOD. /VII/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 30 46 26 53 39 / 5 0 0 0 20
MLU 34 44 25 52 35 / 20 0 0 0 20
DEQ 24 42 22 52 32 / 0 0 0 0 0
TXK 28 43 25 52 37 / 5 0 0 0 10
ELD 29 43 23 52 34 / 5 0 0 0 10
TYR 27 43 30 53 40 / 5 0 0 0 20
GGG 28 44 27 53 39 / 5 0 0 0 20
LFK 33 49 29 53 41 / 10 0 0 10 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING
ZONES: ARZ050-051-059>061-070>073.
LA...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING
ZONES: LAZ001>006-010>014-021.
OK...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING
ZONES: OKZ077.
TX...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING
ZONES: TXZ096-097-108>112-124>126-136>138-149>153.
&&
$$
15
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1229 PM CST SUN FEB 1 2015
.AVIATION...
LOW CIGS THIS MORNING HAVE LIFTED TO MOSTLY MVFR LVLS ACROSS THE
AREA. A STG COLD FRONT JUST REACHING THE KTYR AND KTXK TERMINALS.
WSHFT ALONG FRONT TO INCREASE NW 15 KTS...WITH GUSTS OVER 25 KTS
INTO NE TX/SE OK. NARROW BAND OF HEAVY SHOWERS...CURRENTLY NEAR
KSHV AND KELD...JUST AHEAD OF FRONT. ISOLD TSTMS POSSIBLE...MAINLY
SOUTH OF I-20 AS PREFRONTAL TEMPS WARM INTO UPPER 60S TO LOWER 70S.
PREFRONTAL WINDS S-SW 10 TO 15 KTS. SKIES BECMG VFR SKC FROM THE
WEST BEGINNING AROUND 02/00Z. GUSTY NW WINDS TO CONTINUE UNTIL
AROUND 02/06Z...THEN BECMG NORTHERLY AT 5 TO 10 KTS THRU REMAINDER
OF FCST PERIOD./VII/.
&&
.PREV DISCUSSION... /ISSUED 1141 AM CST SUN FEB 1 2015/
DISCUSSION...
A 20-30NM WIDE BAND OF SHOWERS AND ISOLATED THUNDERSTORMS HAS
DEVELOPED ALONG A COLD FRONT...WHICH EXTENDS FROM NEAR LIT...TO
ADF...TO TXK...TO JXI/TYR...TO JUST E OF CRS AND TPL AS OF 17Z.
THIS CONVECTION HAS RESULTED IN 20-25KT WIND GUSTS ACROSS SW AR/NE
TX WITH ITS PASSAGE...ALTHOUGH WEAK CIN CONTRIBUTED BY THE LOW
LEVEL INVERSION NOTED ON THE 12Z KSHV RAOB CONTINUES TO HOLD
ACROSS SW AR/EXTREME NRN LA. FARTHER S...SOME BREAKS IN THE
STRATUS HAS BEEN NOTED...WITH LFK HAVING JUMPED INTO THE MID 70S.
SHOULD SEE SOME WEAK SFC BASED INSTABILITY DEVELOP THIS AFTERNOON
FROM LOWER TOLEDO BEND COUNTRY NE ACROSS NCNTRL LA AS SOME OF
THESE BREAKS MAY EXTEND NE OVER THESE AREAS...WITH CONTINUED
MOISTURE ADVECTION/BNDRY LYR HEATING CONTRIBUTING TO 500-800 J/KG
OF MLCAPE. FRONTAL CONVERGENCE REMAINS STRONG LATE THIS MORNING
WHERE THE CONVECTION IS ONGOING...WITH THE SHORT TERM PROGS
ACTUALLY MAINTAINING THE FRONTAL CONVERGENCE THROUGH THE AFTERNOON
WHERE A LITTLE BETTER INSTABILITY IS EXPECTED. HOWEVER...LAPSE
RATES ALOFT WILL BE QUITE MARGINAL...WITH THE BEST FORCING
EXPECTED TO BE ON THE NRN FRINGE OF THE WEAK INSTABILITY AXIS.
WHILE BRIEF WIND GUSTS TO 30-35KTS WILL BE POSSIBLE WITH THE
STRONGER CONVECTION...HAVE LOW CONFIDENCE IN SVR CONVECTION DEVELOPING
OVER THE AREA THIS AFTERNOON GIVEN THE VERY MARGINAL THERMODYNAMIC
ENVIRONMENT.
HOWEVER...THE FRONT IS MAKING A LITTLE FASTER PROGRESS SE THAN
EARLIER ANTICIPATED...WITH THE LATEST HRRR RUN HANDLING THE
FRONTAL PROGRESSION QUITE WELL. THE 12Z NAM IS ABOUT 3 HOURS
SLOWER...WITH THE GFS POSITION VERY SIMILAR IF NOT A TAD SLOWER
THAN THE HRRR. THUS...THE CONVECTION SHOULD MOVE OUT OF THE REGION
A LITTLE FASTER THAN EXPECTED LATER THIS AFTERNOON.
HOWEVER...THE MSAS ANALYSIS DEPICTS 3-5MB/3 HOUR PRESSURE RISES
ARE NOTED BEHIND THE FRONT FROM N TX INTO CNTRL OK/KS...WITH A
TIGHTENING PRESSURE GRADIENT BEHIND A SFC LOW OVER SW MO. IN
FACT...THE VISIBLE SATELLITE IMAGERY INDICATES NW TO SE STRIATIONS
IN THE STRATOCU FIELD OVER N TX/MUCH OF CNTRL AND ERN
OK...INDICATIVE OF THE STRONGER WINDS NEAR 2.5-3KFT. THESE
STRONGER WINDS SHOULD WORK INTO MCCURTAIN COUNTY OK AND THE WRN
SECTIONS OF E TX THIS AFTERNOON...AND FOR THAT REASON...HAVE
HOISTED A LAKE WIND ADVISORY FOR THESE AREAS THROUGH 10Z MONDAY.
WILL LIKELY HAVE TO EXPAND THE ADVISORY E INTO SW AR/WRN LA
LATER...BUT WILL ADDRESS THAT WITH THE AFTERNOON FORECAST PACKAGE.
HAVE ALSO RAISED TEMPS A FEW DEGREES ACROSS THE WARM SECTOR PER
THE 17Z OBS...WHILE ALSO REFLECTING A TEMP FALL FOR THE AFTERNOON
BEHIND THE FRONT. ALSO ADUSTED POPS AS WELL PER CURRENT RADAR
TRENDS.
ZONE UPDATE/NPW ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 65 31 47 28 56 / 90 10 0 0 0
MLU 68 35 45 27 53 / 80 30 0 0 0
DEQ 55 26 45 24 54 / 60 10 0 0 0
TXK 59 29 43 27 54 / 90 10 0 0 0
ELD 62 30 45 25 53 / 90 10 0 0 0
TYR 64 27 45 31 55 / 60 10 0 0 0
GGG 65 29 44 30 55 / 80 10 0 0 0
LFK 75 33 49 30 57 / 60 10 0 0 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING
ZONES: OKZ077.
TX...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING
ZONES: TXZ096-108>111-124-125-136-137-149-150.
&&
$$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1141 AM CST SUN FEB 1 2015
.DISCUSSION...
A 20-30NM WIDE BAND OF SHOWERS AND ISOLATED THUNDERSTORMS HAS
DEVELOPED ALONG A COLD FRONT...WHICH EXTENDS FROM NEAR LIT...TO
ADF...TO TXK...TO JXI/TYR...TO JUST E OF CRS AND TPL AS OF 17Z.
THIS CONVECTION HAS RESULTED IN 20-25KT WIND GUSTS ACROSS SW AR/NE
TX WITH ITS PASSAGE...ALTHOUGH WEAK CIN CONTRIBUTED BY THE LOW
LEVEL INVERSION NOTED ON THE 12Z KSHV RAOB CONTINUES TO HOLD
ACROSS SW AR/EXTREME NRN LA. FARTHER S...SOME BREAKS IN THE
STRATUS HAS BEEN NOTED...WITH LFK HAVING JUMPED INTO THE MID 70S.
SHOULD SEE SOME WEAK SFC BASED INSTABILITY DEVELOP THIS AFTERNOON
FROM LOWER TOLEDO BEND COUNTRY NE ACROSS NCNTRL LA AS SOME OF
THESE BREAKS MAY EXTEND NE OVER THESE AREAS...WITH CONTINUED
MOISTURE ADVECTION/BNDRY LYR HEATING CONTRIBUTING TO 500-800 J/KG
OF MLCAPE. FRONTAL CONVERGENCE REMAINS STRONG LATE THIS MORNING
WHERE THE CONVECTION IS ONGOING...WITH THE SHORT TERM PROGS
ACTUALLY MAINTAINING THE FRONTAL CONVERGENCE THROUGH THE AFTERNOON
WHERE A LITTLE BETTER INSTABILITY IS EXPECTED. HOWEVER...LAPSE
RATES ALOFT WILL BE QUITE MARGINAL...WITH THE BEST FORCING
EXPECTED TO BE ON THE NRN FRINGE OF THE WEAK INSTABILITY AXIS.
WHILE BRIEF WIND GUSTS TO 30-35KTS WILL BE POSSIBLE WITH THE
STRONGER CONVECTION...HAVE LOW CONFIDENCE IN SVR CONVECTION DEVELOPING
OVER THE AREA THIS AFTERNOON GIVEN THE VERY MARGINAL THERMODYNAMIC
ENVIRONMENT.
HOWEVER...THE FRONT IS MAKING A LITTLE FASTER PROGRESS SE THAN
EARLIER ANTICIPATED...WITH THE LATEST HRRR RUN HANDLING THE
FRONTAL PROGRESSION QUITE WELL. THE 12Z NAM IS ABOUT 3 HOURS
SLOWER...WITH THE GFS POSITION VERY SIMILAR IF NOT A TAD SLOWER
THAN THE HRRR. THUS...THE CONVECTION SHOULD MOVE OUT OF THE REGION
A LITTLE FASTER THAN EXPECTED LATER THIS AFTERNOON.
HOWEVER...THE MSAS ANALYSIS DEPICTS 3-5MB/3 HOUR PRESSURE RISES
ARE NOTED BEHIND THE FRONT FROM N TX INTO CNTRL OK/KS...WITH A
TIGHTENING PRESSURE GRADIENT BEHIND A SFC LOW OVER SW MO. IN
FACT...THE VISIBLE SATELLITE IMAGERY INDICATES NW TO SE STRIATIONS
IN THE STRATOCU FIELD OVER N TX/MUCH OF CNTRL AND ERN
OK...INDICATIVE OF THE STRONGER WINDS NEAR 2.5-3KFT. THESE
STRONGER WINDS SHOULD WORK INTO MCCURTAIN COUNTY OK AND THE WRN
SECTIONS OF E TX THIS AFTERNOON...AND FOR THAT REASON...HAVE
HOISTED A LAKE WIND ADVISORY FOR THESE AREAS THROUGH 10Z MONDAY.
WILL LIKELY HAVE TO EXPAND THE ADVISORY E INTO SW AR/WRN LA
LATER...BUT WILL ADDRESS THAT WITH THE AFTERNOON FORECAST PACKAGE.
HAVE ALSO RAISED TEMPS A FEW DEGREES ACROSS THE WARM SECTOR PER
THE 17Z OBS...WHILE ALSO REFLECTING A TEMP FALL FOR THE AFTERNOON
BEHIND THE FRONT. ALSO ADUSTED POPS AS WELL PER CURRENT RADAR
TRENDS.
ZONE UPDATE/NPW ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 65 31 47 28 56 / 90 10 0 0 0
MLU 68 35 45 27 53 / 80 30 0 0 0
DEQ 55 26 45 24 54 / 60 10 0 0 0
TXK 59 29 43 27 54 / 90 10 0 0 0
ELD 62 30 45 25 53 / 90 10 0 0 0
TYR 64 27 45 31 55 / 60 10 0 0 0
GGG 65 29 44 30 55 / 80 10 0 0 0
LFK 75 33 49 30 57 / 60 10 0 0 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING
ZONES: OKZ077.
TX...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING
ZONES: TXZ096-108>111-124-125-136-137-149-150.
&&
$$
15
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
412 PM EST SUN FEB 1 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 411 PM EST SUN FEB 1 2015
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER
THE WRN CONUS AND A TROUGH FROM NRN HUDSON BAY INTO ERN CANADA
RESULTING IN WNW NRN STREAM FLOW THROUGH THE NRN GREAT LAKES. TO THE
SOUTH...A VIGOROUS SHRTWV TROUGH INTO NRN IL WAS BRINGING HEAVY SNOW
FROM IA INTO THE SRN LAKES. AT THE SFC...DRY NE FLOW PREVAILED
THROUGH LAKE SUPERIOR AND UPPER MI BETWEEN A 1036 MB HIGH OVER ERN
NORTH DAKOTA AND A 1003 MB LOW OVER ERN IL. 900 MB TEMPS AROUND -22C
PROVIDED ENOUGH INSTABILITY FOR PERSISTENT LES. HOWEVER...INVERSION
HEIGHTS AROUND 3K FT AND A DGZ BELOW 1K FT HAS LIMITED INTENSITY AND
ACCUMULATION POTENTIAL.
TONIGHT...EXPECT THE WINDS TO GRADUALLY BACK TO NRLY AS THE IL LOW
MOVES TO THE E AND THE HIGH BUILDS INTO THE CNTRL PLAINS. WITH A
RELATIVELY LIGHT WIND FIELD...LAND BREEZE EFFECTS AND THE
DEVELOPMENT OF LOCALIZED CIRCULATIONS OR AREAS OF CONVERGENCE WILL
BE MORE LIKELY. THE HIGHER RES MODELS SUGGEST THAT A BAND MAY
DEVELOP THAT WOULD AFFECT FAR ERN OR WRN ALGER COUNTY TONIGHT.
INVERSION HEIGHTS REMAINING AROUND 3K FT SHOULD LIMIT ACCUMULATION
POTENTIAL TO A FEW INCHES. THERE MAY ALSO BE A SHORELINE PARALLEL
BAND NEAR THE WEST BUT CONFIDENCE IN WHERE IT MAY AFFECT THE
SHORELINE IS LOW.
BESIDES THE LES...TEMPS WILL FALL BELOW ZERO TONIGHT...ESPECIALLY
OVER THE FAR ERN COUNTIES AND ALONG THE WI BORDER OF THE INTERIOR WEST.
FORTUNATELY...WITH THE LIGHT WINDS AND SOME LAKE MODERATION/LAKE
EFFECT CLOUDS...WIND CHILLS SHOULD REMAIN IN THE -10 TO -20
RANGE...NOT REACHING ADVY CRITERIA.
MON...SOME LINGERING LES IN THE N TO NW SNOWBELTS AS 900 MB TEMPS
WILL BE AROUND -22C WILL BE PUSHED OFFSHORE AS A TROUGH DEVELOPS
OVER NRN MN INTO NRN LAKE SUPERIOR AND THE HIGH PRES SHIFTS TO THE
OH VALLEY. TEMPS WILL REMAIN BELOW NORMAL IN THE 10-15F RANGE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 350 PM EST SUN FEB 1 2015
COLD CONDITIONS WITH BELOW NORMAL TEMPS EXPECTED THIS WEEK AS
RIDGING FROM EASTERN RUSSIA AND THE BERING SEA TO THE WESTERN CONUS
ALLOWS TROUGHING TO EXPAND ACROSS THE GREAT LAKES FM EASTERN CANADA.
RIDGING BEGINS TO FLATTEN BY END OF THE EXTENDED PERIOD SUGGESTING
THAT TEMPS WILL BOUNCE BACK TOWARD NORMAL OR MAYBE ABOVE BEYOND NEXT
WEEKEND. DAYTIME HIGHS FOR A COUPLE DAYS WILL STAY IN THE SINGLE
DIGITS BUT OTHERWISE WILL BE IN THE TEENS. NIGHTTIME LOWS WILL MAINLY
BE IN THE SINGLE DIGITS BLO ZERO TO THE SINGLE DIGITS ABOVE. MAY HAVE
TO DEAL WITH WIND CHILL ISSUES...ESPECIALLY ON THURSDAY MORNING.
COLDEST DAYS LIKELY WEDNESDAY AND THURSDAY AS CORE OF ARCTIC AIR WITH
H85 TEMPS BLO -25C SWEEPS OVER THE UPPER GREAT LAKES. WIDESPREAD SNOW
CHANCES STILL ON THE LOWER SIDE IN THIS PATTERN. FOR LAST COUPLE
DAYS...PRIMARY EXTENDED MODELS OF ECMWF/GFS AND GEM-NH ALONG WITH GFS
ENSEMBLES HAVE HINTED AT BETTER SHOT OF SNOW OVER MUCH OF THE UPPER
LAKES REGION FRIDAY AFTERNOON INTO SATURDAY AS A COLD FRONT SLIDES
ACROSS THE AREA. DETAILS STILL NEED TO BE SORTED OUT THOUGH AS MODEL
CONSISTENCY IS LACKING.
AT THE BEGINNING OF THE LONG TERM...HIGH PRESSURE CENTER SETTLES TO
THE LOWER MISSISSIPP RIVER VALLEY ON MONDAY EVENING. A TROUGH WILL
BE APPROACHING LK SUPERIOR FM NORTHERN ONTARIO. WEAK SHORTWAVE/PV
ANAMOLY SLIDES THROUGH AND SOUNDINGS EVEN INLAND SHOW MARGINAL DEEP
MOISTENING H8-H5 WITH WEAK LIFT. LGT SNOW OR FLURRIES MOST AREAS
LATER MONDAY EVENING INTO THE OVERNIGHT. BIGGER IMPACT MAY OCCUR
OVER NORTHERN KEWEENAW PENINSULA AS BAND OF MODERATE TO POSSIBLY
HEAVY LES COULD BE ONGOING. LIFT FM THE DISTURBANCE ALONG WITH H85
TEMPS NEAR -20C YIELDS 1000-850MB LAPSE RATES OVER 9C/KM WHERE
STRONGER CONVERGENCE COMES TOGETHER. LOCAL HIRES WRF MODEL SEEMS
REASONABLE SHOWING OVER 0.05 INCH OF QPF PER HOUR IN HEAVIER
BANDING. SO WITH SLR/S OVER 20:1...COULD BE OVER 1 INCH OF SNOW PER
HOUR...WHICH FITS THIS TYPE OF LES REGIME. DOES APPEAR THAT WITH
ARRIVAL OF TROUGH THE HEAVIEST SNOW WILL NOT LAST PROBABLY MORE THAN
A FEW HOURS. WIND GUSTS 20-25 MPH WILL BLOW/DRIFT SNOW AS WELL.
OVERALL...SEEMS LIKE MODELS/PATTERN RECOGNITION POINTS TO ADVY FOR
TIP OF KEWEENAW MONDAY EVENING...BEFORE THE LES SINKS ACROSS REST OF
KEWEENAW AND BECOMES MORE MULTIBAND IN TYPE. CONTINUE TO MENTION IN
HWO.
ONCE THE SFC TROUGH MOVES THROUGH LATE MONDAY NIGHT INTO TUESDAY
MORNING AND LARGER SCALE FORCING EVADES...EXPECT NW FLOW LES THROUGH
TUESDAY NIGHT. LOW INVERSIONS BLO 4KFT AND NEUTRAL TO ANTICYLONIC
FLOW WILL LIMIT INTENSITY OF LES DESPITE ALL OF THE CLOUD BEING
WITHIN THE DGZ. FLUFFY ACCUMS EXPECTED BUT LOW IMPACT AS WINDS WILL
BE LIGHT. AS THIS OCCURS...LOW PRESSURE SYSTEM MOVES OVER THE
NORTHERN PLAINS AND EVENTUALLY SPREADS LGT SNOW OVER THE WESTERN
GREAT LAKES REGION ON TUESDAY NIGHT. NAM FARTHER NORTH WITH THE QPF
COMPARED TO THE MORE CONSISTENT ECWMF/GFS AND GEM-NH. WILL SHOOT FOR
A MAINLY DRY FORECAST AWAY FM THE LK SUPERIOR LES.
PRIMARY HAZARDOUS WEATHER POTENTIAL WILL BE TIED TO LAKE EFFECT AND
BLSN/DRSN THAT RAMPS UP WEDNESDAY AND WEDNESDAY NIGHT FOR AREAS NEAR
LK SUPERIOR FAVORED BY NORTHWEST WINDS. THIS IS IN WAKE OF THE LOW
PRESSURE SYSTEM AND ASSOCIATED COLD FRONT THAT CROSS THE AREA ON
TUESDAY NIGHT. INVERSION HEIGHTS RISING TO AT LEAST 8KFT AND LAKE
EQL OVER 10KFT POINT TO MODERATE TO HEAVY SNOW. DUE TO DEPTH OF COLD
THOUGH...SOUNDINGS INDICATE MOST OF THE LAKE EFFECT CONVECTIVE LAYER
WILL BE AT TEMPS BLO -20C. SO...LOOKING AT SMALL SNOW FLAKES GOOD AT
REDUCING VSBY...BUT NOT PILING UP A LOT OF SNOW. WINDS IN THE MIXED
LAYER 25-30 KTS...SO BLSN/DRSN WILL BE PREVALENT WITH THE FINE SNOW
FLAKES. EXPECT THERE WILL NEED TO BE SOME WINTER WEATHER HEADLINES
CENTERED ON WEDNESDAY INTO WEDNESDAY NIGHT.
AWAY FM THE LES AND BLSN/DRSN...APPEARS CONDITIONS OVER AT LEAST
INTERIOR WEST WILL BE CLOSE TO WIND CHILL ADVISORY CRITERIA LATE
WEDNESDAY NIGHT INTO THURSDAY MORNING. EXPECT READINGS 20 TO 25 BLO
ZERO WHICH IS CLOSE TO...BUT NOT QUITE REACHING CRITERIA OF 25 TO 35
BLO. WILL CONTINUE TO MENTION THIS IN THE HWO...BUT IS NOT APPEARING
TO BE AN OVERWHELMING LOW WIND CHILL EVENT.
ANOTHER TROUGH...REALLY MORE OF A WARM FRONT ALOFT...SLIDES OVER
NORTHERN ONTARIO AND LK SUPERIOR THURSDAY AFTN THROUGH THURSDAY
NIGHT. WINDS BACKING SW AHEAD OF THE TROUGH IN LOW-LEVELS WILL PUSH
LES OVER LK SUPERIOR AND WINDS APPEAR TO HAVE TOO MUCH WESTERLY
COMPONENT TO RESULT IN LES OFF LK MICHIGAN FM KISQ TO KERY. MID-
LEVEL MOISTURE WITH WEAK LIFT MAY SQUEEZE OUT LGT SNOW OR FLURRIES
FOR MOST OF THE CWA.
CONSISTENCY NOT THERE YET FOR FRIDAY AND SATURDAY SO WILL RUN WITH
FORECAST CONSENSUS ATTM. BEST CHANCES OF A WIDESPREAD SNOW PROBABLY
FRIDAY NIGHT WITH INCREASING UNCERTAINTY FOR THAT ON SATURDAY. FRONT
WILL BE IN THE VCNTY AND LATEST INDICATIONS FM MODELS AND HAND DRAWN
PROG FM WPC SHOWS IT MAINLY SOUTH OF AREA ON SUNDAY WITH LOW CHANCES
FOR LES IN AN EASTERLY FLOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1251 PM EST SUN FEB 1 2015
MVFR CONDITIONS WITH OCNL IFR VSBY IN LAKE CLOUDS AND LIGHT SNOW
SHOWERS WILL CONTINUE AT KSAW AND KCMX THROUGH MUCH OF THE PERIOD IN
A NE-N FLOW. KIWD WILL SEE VFR CONDITIONS EARLY THIS AFTERNOON
MORNING BEFORE TRANSITIONING TO MVFR CONDITIONS THIS AFTERNOON AS
WINDS SHIFT FROM ENE TO MORE ONSHORE NNE FLOW. WITH ONSHORE FLOW
THIS AFTERNOON INTO TONIGHT...EXPECT MVFR CLOUD DECK AND POSSIBLE
LIGHT SNOW SHOWERS AT KIWD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 350 PM EST SUN FEB 1 2015
NORTHEAST WINDS BECOME WEST AHEAD OF APPROACHING TROUGH ON
MONDAY...THEN TURN TO THE NORTHWEST BEHIND THE TROUGH ON TUESDAY.
WINDS THROUGH TUESDAY AT OR BLO 30 KTS. HEAVY FREEZING SPRAY OVER
PORTIONS OF LK SUPERIOR ON MONDAY NIGHT. STRONG COLD FRONT MOVES
ACROSS LK SUPERIOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. NW
WINDS COULD REACH LOW-END GALES IN GUSTS WEDNESDAY AND WEDNESDAY
EVENING. HEAVY FREEZING SPRAY IS EXPECTED DURING THIS
TIME...ESPECIALLY FOR EAST HALF OF LK SUPERIOR. WINDS BACK SW ON
THURSDAY AHEAD OF ANOTHER TROUGH THAT CROSSES ON FRIDAY...THEN
BECOME NORTHERLY BEHIND THE TROUGH INTO NEXT WEEKEND. WINDS SHOULD
STAY AT OR BLO 30 KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
310 PM EST SUN FEB 1 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO/CLIMATE
.SYNOPSIS...
ISSUED AT 305 PM EST SUN FEB 1 2015
A MAJOR WINTER STORM WILL CONTINUE TO IMPACT THE REGION THROUGH
EARLY MONDAY MORNING BEFORE DEPARTING. BLOWING AND DRIFTING SNOW
WILL CONTINUE TO LEAD TO DANGEROUS TRAVEL ESPECIALLY NEAR AND
SOUTH OF I-96 AND TOWARD I-94. STORM TOTAL ACCUMULATIONS
(INCLUDING WHAT HAS FALLEN ALREADY) BY MONDAY MORNING WILL RANGE FROM A
COUPLE INCHES ALONG ROUTE 10 TO AS MUCH AS 12 TO 16 INCHES ALONG
I-94. WIND CHILL READINGS WILL FREQUENTLY BE BELOW ZERO FOR MOST
MORNINGS THIS WEEK. OCCASIONAL SNOW SHOWERS ARE POSSIBLE THROUGH
MID WEEK WITH ADDITIONAL SNOW SHOWERS ONCE AGAIN FOR THE WEEKEND.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 305 PM EST SUN FEB 1 2015
STORM TERM DISCUSSION: LITTLE CHANGE TO OUR EXISTING
FORECAST...WITH CONTINUED SNOW AND BLOWING SNOW THROUGH TONIGHT
WITH SNOW COVERED ROADS AND DRIFTING SNOW LEADING TO DANGEROUS
TRAVEL. RESIDUAL IMPACTS TO THE MONDAY MORNING COMMUTE ARE
LIKELY...ESPECIALLY FOR SECONDARY AND RURAL ROADS WHERE UNPLOWED
SNOW MAY BE A SIGNIFICANT PROBLEM FOR TRAVEL. THE GFS HAS LED THE
WAY WITH THIS SYSTEM AND WILL CONTINUE TO BE FOLLOWED CLOSELY. WV
AND IR IMAGERY SHOW THE WESTERN EDGE OF THIS STORM STILL EXTENDS
INTO EASTERN NEBRASKA AND WESTERN IOWA...SO STILL A WAYS TO GO YET
AS THE DEFORMATION ZONE WORKS INTO THE SOUTHERN CWA TONIGHT.
LOOKING AT THE 12Z GFS MULTI- LAYER FN VECTOR CONVERGENCE FROM
H925 UP TO H500...THERE ARE INDICATIONS THAT BOTH THE I-94 REGION
AND ALSO A SEPARATE AREA FROM SOUTH HAVEN TO GRR WILL BE
UNDERNEATH DEEP FORCING...WITH SOME MESOSCALE HEAVY BANDS POSSIBLE
WITH ENHANCED SNOWFALL RATES OF 1" OR MORE PER HOUR. THAT
SAID...THIS IS A VERY FINE SNOW...AND SETTLING/COMPRESSION
UNDOUBTEDLY WILL OCCUR. NEVERTHELESS...AMOUNTS WILL CONTINUE
PILING UP THROUGH TONIGHT AS THE WORST OF THE STORM IS EXPECTED TO
MANIFEST FROM 21Z THROUGH 06Z.
THE DRY SLOT IS EXPECTED TO MOVE AS FAR NORTH AS EXTREME SE
MICHIGAN...AND AS SUCH...WEAKLY POSITIVE OR EVEN NEGATIVE EPV ON
THE NOSE OF THIS DRY SLOT WILL IMPACT AREAS ALONG/EAST OF AN AZO TO
LAN LINE THROUGH 06Z. THIS WILL BE COINCIDENT WITH COMPLETE
SATURATION THROUGH THE COLUMN AND ALSO STRONG FGEN WITH THE
DEFORMATION ZONE FORECAST TO MOVE INTO THE SOUTHERN/SE CWA BY BOTH
THE NAM AND GFS. ALL THIS ADDS CONFIDENCE TO STEADY SNOWFALL RATES
OF AROUND OR EVEN A BIT MORE THAN 1"/HOUR TONIGHT NEAR AND SOUTH
OF I-96 AND PARTICULARLY NEAR/EAST OF AN AZO TO LAN LINE. BY 00Z
OR SHORTLY THEREAFTER...THE DGZ SPLITS INTO TWO REGIONS AS LOW
LEVEL TEMPS CONTINUE TO DECLINE...SO A "BONUS" REGION FOR
DENDRITIC GROWTH WILL EXIST FOR A SHORT TIME BEFORE THE STORM
WINDS DOWN. NOT SURE HOW MUCH THIS WILL ADD TO THE ACCUMS...BUT
SOME ENHANCEMENT IS POSSIBLE.
AMOUNTS SO FAR NEAR/SOUTH OF I-96 HAVE GENERALLY BEEN 4 TO 8
INCHES. AN ADDITIONAL 4 TO 8 INCHES IS EXPECTED TONIGHT...BRINGING
STORM TOTAL ACCUMULATIONS IN THE 8 TO 16 INCH RANGE. THIS IS BASED
ON A WEIGHTED BLEND OF ALL AVAILABLE SHORT/LONG RANGE MODELS AS
WELL AS WPC GUIDANCE. NORTH OF I-96...WHERE AN ADVISORY IS IN
PLACE...STORM TOTAL AMOUNTS WILL TAIL OFF TO AROUND 8 INCHES
ACROSS THE VERY SOUTHERN PORTION OF THE ADVISORY AREA TO AS LITTLE
AS 2 OR 3 INCHES NEAR ROUTE 10.
WINDS...AS ANTICIPATED...HAVE BEEN ON THE UPSWING TODAY. GRR AND
MKG HAVE ALREADY GUSTED TO 30 KNOTS OR GREATER. ALTHOUGH HRRR WIND
GUSTS ARE TOO HIGH BY 5-10 KNOTS...WILL KEEP THE GENERAL THEME IN
MIND WITH OUR GRIDS AND HOLD ONTO GUSTY WINDS THROUGH AT LEAST
06Z. WIND GUSTS TO 40 MPH ARE POSSIBLE BASED ON TRENDS THIS
AFTERNOON...MAINLY FROM MKG TO GRR TO LAN...WHERE NE FLOW SEEMS TO
BE MAXIMIZED IN THESE TYPES OF SYSTEMS. BLOWING AND DRIFTING
SNOW...ESPECIALLY IN RURAL/OPEN AREAS...WILL BE A SIGNIFICANT
PROBLEM FOR THE DURATION OF THIS EVENT GIVEN THE DRY NATURE OF THE
SNOW AND THE WIND GUSTS.
SHORT TERM DISCUSSION: AFTER THE STORM MOVES OUT AROUND
12Z...EXPECTING A MUCH QUIETER MONDAY ASIDE FROM SOME LAKE EFFECT
SNOW SHOWERS THAT WILL BLOW INLAND AS WINDS BACK FROM N TO W WITH
A RIDGE MOVING INTO THE OHIO VALLEY REGION. ACCUMS ARE ONLY
EXPECTED TO BE A FEW TENTHS OF AN INCH. BY TUESDAY NIGHT...A
CLIPPER WILL BE MOVING THROUGH THE MIDWEST AND WILL SPREAD SOME
LIGHT SNOW INTO SOUTHERN LOWER MICHIGAN. LIGHT ACCUMULATIONS LOOK
PROBABLE AT THIS POINT BASED ON MEDIUM RANGE MODEL QPF.
&&
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 305 PM EST SUN FEB 1 2015
A FEW LIGHT SNOW SHOWERS AND FLURRIES WILL LINGER WEDNESDAY AS A
STRONG UPPER LEVEL PV ANOMALY MOVES ACROSS THE NORTHERN GREAT LAKES
REGION AND IN THE WAKE OF THE ARCTIC COLD FRONT. WIDESPREAD SUB ZERO
READINGS ARE QUITE POSSIBLE BY EARLY THURSDAY MORNING AS A RESULT OF
CLEARING SKIES AND A DRY AIRMASS IN PLACE AS HIGH PRESSURE BUILDS IN
IN CONJUNCTION WITH WITH EXTENSIVE SNOW COVER ACROSS MUCH OF OUR
FCST AREA BY THEN.
HIGH PRESSURE WILL BRING FAIR WEATHER THURSDAY BUT IT WILL BE QUITE
COLD WITH MAX TEMPS ONLY REACHING THE TEENS. TEMPS WILL MODERATE
FRIDAY AND SATURDAY AS THE UPPER LEVEL PATTERN BECOMES ZONAL. A
COLD FRONT DROPPING DOWN FROM THE NW WILL BRING A CHANCE OF LIGHT
SNOW FRIDAY NIGHT AND/OR SATURDAY FOLLOWED BY THE ARRIVAL OF ANOTHER
COLDER AIRMASS BY SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY)
ISSUED AT 1145 AM EST SUN FEB 1 2015
A SNOWSTORM WILL CONTINUE IN PROGRESS THIS AFTERNOON THROUGH THIS
EVENING RESULTING IN WIDESPREAD LIFR CONDITIONS THROUGH LATE THIS
EVENING DUE TO MODERATE TO HEAVY SNOW AND BLOWING SNOW. NORTHEAST
WINDS WILL CONTINUE TO INCREASE TO 15 TO 25 KTS WITH FREQUENT GUSTS
TO AROUND 30 KTS LATE THIS AFTERNOON AND EVENING WHICH WILL FURTHER
REDUCE VISIBILITIES IN BLOWING SNOW. LIGHT RIME ICING WILL BE
POSSIBLE GENERALLY BELOW 2000 FT AGL.
CONDITIONS WILL GRADUALLY IMPROVE TO IFR THEN MVFR DURING THE EARLY
MORNING HOURS MONDAY AS THE SNOW MOVES OUT AND CIGS BEGIN TO
IMPROVE. NORTH WINDS WILL REMAIN BRISK AT 15 TO 25 KTS OVERNIGHT.
CONDITIONS WILL GRADUALLY IMPROVE TO VFR MID TO LATE MONDAY MORNING
WHEN WIND SPEEDS WILL DIMINISH A LITTLE BIT OUT OF THE NNW AT 15 TO
20 KTS. CONDITIONS SHOULD THEN REMAIN VFR THROUGH 18Z MON.
&&
.HYDROLOGY...
ISSUED AT 300 PM EST SUN FEB 1 2015
ICE FORMATION ON RIVERS IS THE IMMEDIATE HYDRO CONCERN. ARCTIC AIR
HAS ARRIVED WITH THE COLDEST TEMPS EXPECTED MONDAY WITH SIMILAR
TEMPS FOR THURSDAY AS ANOTHER ARCTIC FRONT MOVES THROUGH. LOWS
TONIGHT AND MONDAY MORNING WILL DROP INTO THE SINGLE DIGITS. COLD
TEMPERATURES ARE EXPECTED THROUGH THE REST OF THE WEEK SO ICE
DEVELOPMENT WILL CONTINUE...PLUS THE SNOW THAT FALLS THROUGH
MONDAY MORNING WILL ALSO HELP WITH ICE DEVELOPMENT. ICE IS
EXPECTED TO REMAIN FAIRLY STABLE AS TEMPS STAY CHILLY.
&&
.CLIMATE...
ISSUED AT 153 PM EST SUN FEB 1 2015
FEB 1ST RECORD SNOWFALL FOR GRR IS 6.1" IN 2001.
FEB 1ST RECORD SNOWFALL FOR LAN IS 6.2" IN 1967.
FEB 1ST RECORD SNOWFALL FOR MKG IS 14.2" IN 1965.
WHILE OFFICIAL LONG TERM SNOWFALL RECORDS ARE NOT MAINTAINED
OUTSIDE OF THESE LOCAL CLIMATOLOGICAL DATA (LCD) STATIONS...SNOWFALL
AMOUNTS OF 10" OR MORE IN A SINGLE CALENDAR DAY WILL LIKELY RANK
IN THE TOP 10 OR TOP 5 FOR THE ENTIRE MONTH OF FEBRUARY FOR MANY
LOCATIONS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING UNTIL 6 AM EST MONDAY FOR MIZ056>059-
064>067-071>074.
WINTER WEATHER ADVISORY UNTIL 6 AM EST MONDAY FOR MIZ037>040-
043>046-050>052.
LM...NONE.
&&
$$
SYNOPSIS...HOVING
SHORT TERM...HOVING
LONG TERM...LAURENS
AVIATION...LAURENS
HYDROLOGY...EBW/HOVING
CLIMATE...HOVING
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1153 AM CST Sun Feb 1 2015
...18Z Aviation Update...
.UPDATE...
Issued at 1030 AM CST SUN FEB 1 2015
The cold front has entered western Missouri during the past hour.
Low pressure currently located over the area is strengthening and
there is a widespread area of increasing pressure rises across
Kansas. This intensification will result in windy conditions
behind the advancing cold front, with frequent gusts to 35 mph.
Continuing to see light rainfall develop overhead at this time,
coincident with the surface low and associated cold front. This
area of light rain will eventually shift to the northeast. Will
continue to watch precipitation wrap around the back side of this
maturing storm system. The past several runs of the HRRR support
recent model output with bringing an area of flurries into the
region beginning mid/late afternoon across northern portions of
the area and spreading southeast deeper into the Missouri Ozarks
this evening. Brief loss of cloud ice will need to be monitored,
which would result in a brief period of drizzle/freezing drizzle
depending upon surface temperatures. However, deeper cold air
should quickly surge into the region and flurries should dominate
this evening. Cannot rule out a minor dusting of grassy surfaces
in some spots tonight, but overall, little if any accumulation is
expected.
&&
.SHORT TERM...(Today and Tonight)
It was a rainy night over extreme southeast Kansas and the
Missouri Ozarks. Temperatures were in the 30s, while winds were
breezy and generally from the south.
Nearly 100 percent coverage of measurable rain occurred this
morning as a large shield of precipitation was detected on radar
over the entire state of Missouri. More rain is expected this
morning, followed by a change over to flurries or light snow late
this morning and afternoon.
The forecast looks right on track as nearly all locations will not
experience any measurable snow accumulations. We can not rule out
a dusting to a half inch up north of Highway 54. Warm ground
temperatures, diurnal snowfall, and light rates will make
accumulating snow difficult.
A cold front will bring a colder air mass through southern Missouri
today, allowing for that change over to snow. Temperatures are
expected to drop throughout the day, while winds shift to the
northwest behind the front.
Lingering flurries or light snow are possible this evening,
particularly over central Missouri. Eventually this precipitation
will exit the area by early Monday morning. Overnight lows tonight
will drop into the teens.
.LONG TERM...(Monday through Saturday)
Zonal flow will quickly evolve Monday and Tuesday, allowing for a
brief warm up. We could observe temperatures warming into the 50s
by Tuesday afternoon. Both Monday and Tuesday will remain dry.
Our next cold front will arrive on Wednesday, forcing a band of
snow to impact the region behind it. We think this east to west
oriented band of snow will progress through the area quickly,
leaving behind some very minor accumulations. Air temperatures
will certainly be cold enough for snow to stick to the ground, and
we could see amounts ranging from zero up to two inches Wednesday
night into Thursday morning. We`re still four to five days out, so
this forecast could adjust in the future.
Beyond Thursday, it appears as though a strong upper level ridge
of high pressure will build into the nation`s mid section by
Friday, and persist through the weekend. This will set up a
beautiful upcoming weekend, with temperatures possibly warming
into the 50s and 60s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1145 AM CST SUN FEB 1 2015
Flight conditions will initially bounce around between MVFR and
IFR this afternoon, with both vis and cigs riding the line between
categories. Conditions should then improve to MVFR by evening, and
remain there overnight. A brief period of light snow/flurries is
possible at SGF late tonight, though at this time it doesn`t
appear that significant impacts will result.
In addition to cig/vis challenges, gusty west to northwest winds
will remain a concern through evening. Expect gusts to around 30
KT this afternoon.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
UPDATE...Gagan
SHORT TERM...Cramer
LONG TERM...Cramer
AVIATION...Boxell
AREA FORECAST DISCUSSION...UPDATED
NWS SPRINGFIELD MO
1030 AM CST Sun Feb 1 2015
.UPDATE...
Issued at 1030 AM CST SUN FEB 1 2015
The cold front has entered western Missouri during the past hour.
Low pressure currently located over the area is strengthening and
there is a widespread area of increasing pressure rises across
Kansas. This intensification will result in windy conditions
behind the advancing cold front, with frequent gusts to 35 mph.
Continuing to see light rainfall develop overhead at this time,
coincident with the surface low and associated cold front. This
area of light rain will eventually shift to the northeast. Will
continue to watch precipitation wrap around the back side of this
maturing storm system. The past several runs of the HRRR support
recent model output with bringing an area of flurries into the
region beginning mid/late afternoon across northern portions of
the area and spreading southeast deeper into the Missouri Ozarks
this evening. Brief loss of cloud ice will need to be monitored,
which would result in a brief period of drizzle/freezing drizzle
depending upon surface temperatures. However, deeper cold air
should quickly surge into the region and flurries should dominate
this evening. Cannot rule out a minor dusting of grassy surfaces
in some spots tonight, but overall, little if any accumulation is
expected.
&&
.SHORT TERM...(Today and Tonight)
It was a rainy night over extreme southeast Kansas and the
Missouri Ozarks. Temperatures were in the 30s, while winds were
breezy and generally from the south.
Nearly 100 percent coverage of measurable rain occurred this
morning as a large shield of precipitation was detected on radar
over the entire state of Missouri. More rain is expected this
morning, followed by a change over to flurries or light snow late
this morning and afternoon.
The forecast looks right on track as nearly all locations will not
experience any measurable snow accumulations. We can not rule out
a dusting to a half inch up north of Highway 54. Warm ground
temperatures, diurnal snowfall, and light rates will make
accumulating snow difficult.
A cold front will bring a colder air mass through southern Missouri
today, allowing for that change over to snow. Temperatures are
expected to drop throughout the day, while winds shift to the
northwest behind the front.
Lingering flurries or light snow are possible this evening,
particularly over central Missouri. Eventually this precipitation
will exit the area by early Monday morning. Overnight lows tonight
will drop into the teens.
.LONG TERM...(Monday through Saturday)
Zonal flow will quickly evolve Monday and Tuesday, allowing for a
brief warm up. We could observe temperatures warming into the 50s
by Tuesday afternoon. Both Monday and Tuesday will remain dry.
Our next cold front will arrive on Wednesday, forcing a band of
snow to impact the region behind it. We think this east to west
oriented band of snow will progress through the area quickly,
leaving behind some very minor accumulations. Air temperatures
will certainly be cold enough for snow to stick to the ground, and
we could see amounts ranging from zero up to two inches Wednesday
night into Thursday morning. We`re still four to five days out, so
this forecast could adjust in the future.
Beyond Thursday, it appears as though a strong upper level ridge
of high pressure will build into the nation`s mid section by
Friday, and persist through the weekend. This will set up a
beautiful upcoming weekend, with temperatures possibly warming
into the 50s and 60s.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 549 AM CST SUN FEB 1 2015
For the KSGF/KJLN/KBBG tafs: Low pressure and a cold front over
eastern KS will move quickly east through the taf sites over the
next few hours. Gusty winds will occur behind the front, especially at
KJLN and KSGF. IFR ceilings are common over the area, but progged
soundings and ensemble guidance indicate improving ceilings toward
18z with mvfr ceilings expected thereafter. Light rain/drizzle
should also diminish behind the front. Very light snow may briefly
occur as precipitation tapers off after 16z as colder air moves
in.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
UPDATE...Gagan
SHORT TERM...Cramer
LONG TERM...Cramer
AVIATION...DSA
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1139 AM CST SUN FEB 1 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 221 AM CST SUN FEB 1 2015
MAIN FORECAST CONCERN IS ADDITIONAL SNOW ACCUMULATION THIS MORNING
AND NEAR-BLIZZARD CONDITIONS EXPECTED LATE THIS MORNING AND MUCH
OF THE AFTERNOON.
LATEST RADAR SCANS SHOWS THAT THE SNOW IS BEGINNING TO WANE
OVERALL. SOME EMBEDDED STRONGER SNOW BANDS ARE PRESENT NEAR
SCHUYLER/NORTH BEND WITH ANOTHER ENHANCED AREA DRIFTING NORTHEAST
TO THE OMAHA/CB METRO AREA. METARS ARE SHOWING VISIBILITIES
GENERALLY 1 TO 2 MILES. WE DID HEAR OF ONE REPORT OF THUNDER...BUT
NEVER DID SEE THAT SHOW UP IN THE LIGHTNING DETECTION NET. THUS
FAR SNOW AMOUNTS HAVE BEEN AVERAGING 4 TO 9 INCHES IN THE WINTER
STORM WARNING AREA. MANY AREAS PROBABLY WON`T ACHIEVE THE WINTER
STORM CRITERIA AMOUNT OF 8 INCHES. BUT...WE FEEL THE WINTER STORM
WARNING REMAINS JUSTIFIED DUE TO THE EXTREMELY POOR ROAD
CONDITIONS BEING REPORTED AND THE EXPECTED NEAR-BLIZZARD
CONDITIONS POSSIBLE TODAY WHEN THE WINDS KICK IN. FOR THE
REMAINDER OF THIS MORNING...MOISTURE PROFILES REMAIN DEEP AND
STILL WELL LOCATED WITHIN THE DENDRITIC GROWTH ZONE. THUS SNOW
PRODUCTION REMAINS GOOD...THOUGH OVERALL SYSTEM LIFT IS PULLING
OUT TO THE NORTHEAST. FOR NOW THROUGH THIS AFTERNOON ANOTHER 1 TO
3 INCHES APPEARS LIKELY ACROSS THE COUNTY WARNING AREA WITH THE
HIGHEST AMOUNTS FOCUSED ACROSS EAST-CENTRAL NEBRASKA AND WESTERN
IOWA.
AS OF 9Z WINDS HAVE ALREADY PICKED UP AT OFK/LCG/ONL AND EXPECT
ALL AREAS TO BE VERY WINDY BY LATE THIS MORNING. RUC SOUNDINGS
SUGGEST DECENT MIXING MAY OCCUR THIS AFTERNOON AND WIND GUSTS OVER
40 MPH AREN`T OUT OF THE QUESTION. NOT SURE IF THE STRONGEST WINDS
WILL BE SUSTAINED LONG ENOUGH ALONG WITH LOW VISIBILITIES TO
NECESSITATE A BLIZZARD WARNING. CONDITIONS WILL SURELY BE VERY
POOR...THUS WE ADDED NEAR-BLIZZARD WORDING TO THE LATEST WINTER
STORM WARNING UPDATE. THE SNOW SHOULD BE FINISHED JUST AFTER
SUNSET THIS EVENING AND WINDS WILL STEADILY DECREASE OVERNIGHT AS
WEAK SURFACE HIGH PRESSURE SETTLES IN OVER THE AREA. DECIDED TO
LOWER OVERNIGHT LOWS A FEW DEGREES GIVEN SIGNIFICANT SNOW COVER IN
PLACE.
LOOKS LIKE DRY WEATHER FOR MONDAY AND MONDAY NIGHT. BY TUESDAY A
WEAK CLIPPER SYSTEM TRACKS ACROSS NORTHEAST NEBRASKA AND NORTHWEST
IOWA. SOME LIGHT SNOW MAY OCCUR...OPTED FOR LOW CHANCES FOR NOW.
AS THIS FEATURE MOVES EAST IT STRENGTHENS AND OUR FAR NORTHEASTERN
COUNTIES COULD PICK UP A COUPLE INCHES OF SNOW DURING THE DAY ON
TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 221 AM CST SUN FEB 1 2015
NORTHWEST FLOW ALOFT WILL CONTINUE THROUGH THE END OF THE WEEK
BEFORE A MORE ZONAL FLOW PATTERN SETS UP BY SATURDAY. ONE
SIGNIFICANT SHORTWAVE ROLLING THROUGH THE FLOW WILL BRING ANOTHER
CHANCE FOR SNOW TUESDAY NIGHT AND WEDNESDAY WITH COLDER HIGH
PRESSURE SETTLING INTO THE PLAINS FOLLOWING SHORTWAVE. TIMING AND
TRACK OF SNOW WITH THIS SHORTWAVE IS STILL IN QUESTION...BUT MODELS
SEEM TO BE COMING TOGETHER SOMEWHAT IN SHOWING MUCH OF EASTERN
NEBRASKA AND SOUTHWEST IOWA GETTING LIGHT SNOW AT SOME POINT TUESDAY
NIGHT OR WEDNESDAY. AMOUNTS SHOULD REMAIN IN THE INCH OR TWO RANGE
GIVEN LOWER MOISTURE CONTENT AND PROGRESSIVE MOVEMENT. LOWS TUESDAY
NIGHT IN THE TEENS WILL ONLY GAIN A FEW DEGREES INTO THE 20S
WEDNESDAY GIVEN CLOUDS/PRECIP AND A SWITCH TO NORTHERLY WINDS.
COLDER AIR SETTLING SOUTH BEHIND SHORTWAVE WILL GIVE US A COLD START
THURSDAY MORNING WITH LOWS IN THE SINGLE DIGITS...WITH SOME SUB-ZERO
READINGS LIKELY.
A QUICK REBOUND STILL LOOKS ON TRACK THURSDAY WITH WINDS BECOMING
SOUTHERLY...WHICH CONTINUE FRIDAY AND SATURDAY. THUS A SLIGHT
WARMING TREND IS FORECAST...CLIMBING FROM THE 20S THURSDAY TO THE
30S AND PERHAPS LOWER 40S FRIDAY AND SATURDAY.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1131 AM CST SUN FEB 1 2015
LIFR TO IFR CONDITIONS WILL CONTINUE AT THE TAF SITES THIS
AFTERNOON AS STRONG NORTHWEST WINDS GUSTING TO 35 KTS COMBINED
WITH FALLING AND BLOWING SNOW REDUCE VISIBILITIES TO A HALF MILE
OR LESS. WINDS WILL BEGIN TO DIMINISH AND SNOW WILL TAPER OFF FROM
WEST TO EAST LATE THIS AFTERNOON INTO THE EARLY EVENING HOURS.
AFTER 03-06Z...CONDITIONS SHOULD BEGIN TO SLOWLY IMPROVE WITH VFR
CONDITIONS EXPECTED AT ALL SITES BY 09Z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ011-
016-017-030-031-090>093.
WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ012-015-
018-032>034-042>045-050>053-065>068-078-088-089.
IA...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR IAZ043-055-
056-069-080-091.
WINTER STORM WARNING UNTIL 6 PM CST THIS EVENING FOR IAZ079-090.
&&
$$
SHORT TERM...PEARSON
LONG TERM...DERGAN
AVIATION...KERN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
314 PM EST SUN FEB 1 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE UP THE OHIO VALLEY TONIGHT...AND CROSS THE
STATE ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION
ACROSS THE AREA INTO MONDAY MORNING. A PERIOD OF FREEZING RAIN IS
LIKELY ACROSS THE SOUTHERN AND CENTRAL SECTIONS OF THE STATE
OVERNIGHT. ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY
AFTERNOON INTO TUESDAY...WITH LOW WIND CHILLS TUESDAY MORNING. A
COLD FRONT MOVING THROUGH WEDNESDAY WILL BE ACCOMPANIED BY SOME
LIGHT SNOW...MAINLY IN THE NORTHWESTERN HALF OF THE STATE.
&&
.NEAR TERM /UNTIL 9 PM THIS EVENING/...
PRETTY SOLID BAND OF WAA SNOW IS PUSHING THROUGH WRN PA BUT NOT
MUCH BEHIND IT. MESO MODELS HAVE BEEN PLAYING THAT BREAK UP FOR A
LITTLE WHILE...AND IT LOOKS LIKE IT IS COMING TO FRUITION. THIS
WILL YIELD A 3-4 HOUR BREAK IN THE SNOW FOR MOST PLACES. WHILE IT
HAS BEEN SNOWING ALL DAY OUT THE WINDOW...IT STILL REALLY HAS NOT
STARTED STICKING TO ANYTHING. THIS APPEARS TO BE THE CASE ALMOST
EVERYWHERE IN THE CWA JUDGING BY WEB CAMS. BUT THE HIGHER ELEVS OF
THE LAURELS SHOULD BE GETTING WHITE ANY TIME NOW. WILL JUST WORK
THE POPS AROUND TO TRY TO SHOW THAT LITTLE BREAK...BUT IT IS SUCH
A SMALL-SCALE FEATURE THAT IT MAY JUST END UP WASHING OUT IN THE
BIGGER PICTURE. TEMPS DANCING AROUND 32F IN THE CENTRAL COS BUT
WELL INTO THE M30S IN THE SE. PRECIP THERE WILL BE VERY LIGHT
UNTIL MUCH LATER/THIS EVENING. SO...P-TYPE WILL BE DIFFICULT TO
PIN DOWN. CERTAINLY IF IT DECIDES TO SNOW HEAVILY...IT WILL BE
SNOW FOR THAT TIME...BUT WILL LIKELY BE A MIX WHEN LIGHT IN THE
S/SE. TEMPS MOVE LITTLE ALL EVENING...BUT WILL PROBABLY COOL JUST
A LITTLE WITH WET BULBING. DEWPOINTS ALREADY RISING SOME LOCALLY.
&&
.SHORT TERM /9 PM THIS EVENING THROUGH 6 PM MONDAY/...
THE BEST PERIOD OF SNOW CONTINUES TO LOOK LIKE IT WILL BE BETWEEN
00-09Z WITH THE WORST OF IT ACROSS THE NRN HALF OF THE AREA. THE
WARM AIR ALOFT LOOKS TO MAKE IN-ROADS ALL THE WAY TO I-80 BY
SUNRISE MONDAY. THUS...THE ICING POTENTIAL IS STILL THERE. SO
WHILE THE SNOW AMOUNTS - ESPECIALLY IF YOU ONLY MEASURE IN THE
MORNING - WILL BE LOWER THAN PREVIOUSLY ADVERTISED IN THE SRN HALF
OF THE AREA...THERE IS STILL SOME /WEAK/ JUSTIFICATION FOR HOLDING
ONTO THE WARNING ALONG THE RTE 22 CORRIDOR...FOR NOW.
THE QPF IS A MIXED-BAG OF SIGNALS RIGHT NOW. GFS AND EURO ARE
HOLDING ONTO 0.80 OR MORE IN THE NRN HALF OF THE AREA...WITH ONLY
REAL SNOW THERE. THE NAM AND THE SREF MEAN TOTALS THERE ARE ONLY
ABOUT 0.50. WILL CONTINUE WITH THE PARTY LINE OF 8-10 FOR A STORM
TOTAL...BUT REWORKED THE NUMBERS DOWN BARELY AN INCH ON THE WHOLE
SO THE TERRIBLE DARK BLUE OF 10-14 DOES NOT HIT PEOPLE IN THE
FACE. AGAIN...JUST HALF AN INCH TO AN INCH OF A DOWNWARD MOVE ON
THE SNOW. THIS IS DUE TO THE RELATIVELY HIGH UNCERTAINTY AT THIS
RANGE. STILL LOOKS LIKE A SOLID WARNING ANY WAY YOU SLICE IT UP
FOR OUR ENTIRE NRN HALF. SOME PRETTY WICKED SF RATES WILL BE HAD
OVERNIGHT AND VERY EARLY MONDAY IN THE NORTH AND PERHAPS AS FAR S
AS STATE COLLEGE AND SUNBURY BUT MOST LIKELY - THE HEAVIEST SNOW
WILL BE JUST TO THE NORTH OF THOSE TWO CITIES.
PRECIP CUTS OFF PRETTY QUICKLY AFTER 12Z/14Z IN THE CENTRAL COS.
THE EAST MAY SEE PRECIP LINGER INTO THE MID MORNING AS THE COLD
AIR MOVES IN AND TEMPS DROP. AFTER WHAT MAY ONLY BE A BRIEF
BREAK...THE NW WINDS WILL UPSLOPE INTO THE ALLEGHENIES AND
LAURELS. CAA WILL CREATE NUMEROUS SHSN OVER THE WRN HIGH TERRAIN
AND FLURRIES ELSEWHERE. THERE MAY EVEN BE SOME DECENT SHSN AS THE
PRECIP ENDS IN THE SERN THIRD OF THE AREA. YET ANOTHER REASON TO
NOT MONKEY WITH THE WARNINGS/ADVYS JUST YET. IT COULD BE A MESSY
COMMUTE FOR GROUNDHOG MORNING. WINDS WILL GET STRONG AND RATHER
GUSTY - ESP ON THE HILL TOPS AND IN THE SERN THIRD/DOWNSLOPE AREAS
CLOSEST TO THE DEEPENING LOW MOVING OFF THE COAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY
MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD
NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW
ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY
DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP
WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND
LAUREL HIGHLANDS POSSIBLY NEEDING A WIND CHILL ADVISORY /-15F/
MON NIGHT INTO EARLY TUE.
ENSEMBLE MEAN 5H PATTERN SHOWS AN ALBERTA CLIPPER DIVING SE INTO
THE REGION WED/THU. ALL MED RANGE GUIDANCE TRACKS ASSOC SFC LOW
NORTH OF THE STATE EARLY WED...LIKELY PRODUCING A BIT OF LGT SNOW
ACROSS NORTHERN PA. A WEAK LOW ON TRAILING COLD FRONT COULD
SUPPORT SOME LINGERING LGT SNOW ACROSS THE REGION /MAINLY
ALLEGHENIES/ INTO EARLY THURSDAY.
MODERATING TEMPS AHEAD OF CLIPPER COULD RESULT IN A DAY OF NEAR
NORMAL HIGHS WEDNESDAY. HOWEVER...A REINFORCING SHOT OF ARCTIC
AIR LOOKS NEARLY CERTAIN BEHIND CLIPPER LATE THIS WEEK.
NO RESPITE FROM THE BLW NORMAL TEMPS IN THE EXTENDED...AS LATEST
MED RANGE GUIDANCE MAINTAINS UPPER LVL TROF AXIS ACROSS THE
NORTHEAST CONUS.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
DETERIORATING FLYING CONDS EXPECTED THIS AFTN AND EVENING...AS LOW
PRES APPROACHES FROM THE MIDWEST...SPREADING SNOW AND LOWERING
CIGS ACROSS CENTRAL PA. AT 17Z...IFR CONDS ALREADY NOTED ACROSS
WESTERN PA. UPSTREAM RADAR RETURNS AND LATEST HRRR OUTPUT SUGGESTS
IFR CONDS WILL DEVELOP AT KAOO/KUNV/KIPT BTWN 19Z-21Z. ACROSS THE
SOUTHEAST COUNTIES...LATEST MDL DATA SUGGESTS A BAND OF LGT
SNOW/VIS REDUCTIONS COULD COME THROUGH BTWN 22Z-01Z AT KMDT/KLNS.
HOWEVER...CONFIDENCE IN IFR CONDS WILL INCREASE MARKEDLY AT
KMDT/KLNS BTWN 03Z-06Z...AS HEAVIEST SNOW ARRIVES.
WARMER AIR WORKING INTO THE STATE WILL CHANGE SNOW TO EITHER RAIN
OR FZRA ACROSS THE SOUTHERN HALF OF THE STATE LATE TONIGHT.
HOWEVER....WIDESPREAD IFR TO LIFR CONDS EXPECTED EVERYWHERE IN
CONTINUING PRECIP AND LOW CIGS RESULTING FROM MOIST SE FLOW
ASCENDING THE HIGHER TERRAIN OF CENTRAL PA. MARGINAL LLWS REMAINS
A POSSIBILITY LATE TONIGHT ACROSS SOUTHERN PA...AS CORE OF STRONG
WINDS ALOFT SLIDES ACROSS THE AREA. HOWEVER...LATEST MODEL
SOUNDINGS SUGGEST MOST PLACES WILL REMAIN JUST BLW CRITERIA.
MARKED IMPROVEMENT IS EXPECTED BTWN 15Z-18Z MONDAY...AS LOW PRES
PASSES EAST OF THE AREA...AND DRIER NW FLOW DEVELOPS. FOCUS WILL
SHIFT TOWARD STRONG GUSTY WINDS MON PM. GUSTS TO ARND 40KTS ARE
POSSIBLE MON AFTN AND EVENING...AS STRENGTHENING STORM SYSTEM
PASSES EAST OF PA.
OUTLOOK...
MON...AM RAIN/SNOW AND LOW CIGS. PM GUSTY NW WINDS.
TUE...NO SIG WX EXPECTED.
WED...AM LGT SNOW POSSIBLE NW MTNS.
THU...AM LGT SNOW POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR PAZ004>006-
010>012-017>019-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY UNTIL 8 AM EST MONDAY FOR PAZ033>036-
064>066.
WINTER STORM WARNING UNTIL 8 AM EST MONDAY FOR PAZ024>028-056-
057-059-063.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...FITZGERALD
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
206 PM EST SUN FEB 1 2015
.SYNOPSIS...
LOW PRESSURE WILL MOVE UP THE OHIO VALLEY TONIGHT...AND CROSS THE
STATE ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION
ACROSS THE AREA INTO MONDAY MORNING. A PERIOD OF FREEZING RAIN IS
LIKELY ACROSS THE SOUTHERN AND CENTRAL SECTIONS OF THE STATE
OVERNIGHT. ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY
AFTERNOON INTO TUESDAY...WITH LOW WIND CHILLS TUESDAY MORNING. A
COLD FRONT MOVING THROUGH WEDNESDAY WILL BE ACCOMPANIED BY SOME
LIGHT SNOW...MAINLY IN THE NORTHWESTERN HALF OF THE STATE.
&&
.NEAR TERM /UNTIL 9 PM THIS EVENING/...
PRETTY SOLID BAND OF WAA SNOW IS PUSHING THROUGH WRN PA BUT NOT
MUCH BEHIND IT. MESO MODELS HAVE BEEN PLAYING THAT BREAK UP FOR A
LITTLE WHILE...AND IT LOOKS LIKE IT IS COMING TO FRUITION. THIS
WILL YIELD A 3-4 HOUR BREAK IN THE SNOW FOR MOST PLACES. WHILE IT
HAS BEEN SNOWING ALL DAY OUT THE WINDOW...IT STILL REALLY HAS NOT
STARTED STICKING TO ANYTHING. THIS APPEARS TO BE THE CASE ALMOST
EVERYWHERE IN THE CWA JUDGING BY WEB CAMS. BUT THE HIGHER ELEVS OF
THE LAURELS SHOULD BE GETTING WHITE ANY TIME NOW. WILL JUST WORK
THE POPS AROUND TO TRY TO SHOW THAT LITTLE BREAK...BUT IT IS SUCH
A SMALL-SCALE FEATURE THAT IT MAY JUST END UP WASHING OUT IN THE
BIGGER PICTURE. TEMPS DANCING AROUND 32F IN THE CENTRAL COS BUT
WELL INTO THE M30S IN THE SE. PRECIP THERE WILL BE VERY LIGHT
UNTIL MUCH LATER/THIS EVENING. SO...P-TYPE WILL BE DIFFICULT TO
PIN DOWN. CERTAINLY IF IT DECIDES TO SNOW HEAVILY...IT WILL BE
SNOW FOR THAT TIME...BUT WILL LIKELY BE A MIX WHEN LIGHT IN THE
S/SE. TEMPS MOVE LITTLE ALL EVENING...BUT WILL PROBABLY COOL JUST
A LITTLE WITH WET BULBING. DEWPOINTS ALREADY RISING SOME LOCALLY.
&&
.SHORT TERM /9 PM THIS EVENING THROUGH 6 PM MONDAY/...
THE BEST PERIOD OF SNOW CONTINUES TO LOOK LIKE IT WILL BE BETWEEN
00-09Z WITH THE WORST OF IT ACROSS THE NRN HALF OF THE AREA. THE
WARM AIR ALOFT LOOKS TO MAKE IN-ROADS ALL THE WAY TO I-80 BY
SUNRISE MONDAY. THUS...THE ICING POTENTIAL IS STILL THERE. SO
WHILE THE SNOW AMOUNTS - ESPECIALLY IF YOU ONLY MEASURE IN THE
MORNING - WILL BE LOWER THAN PREVIOUSLY ADVERTISED IN THE SRN HALF
OF THE AREA...THERE IS STILL SOME /WEAK/ JUSTIFICATION FOR HOLDING
ONTO THE WARNING ALONG THE RTE 22 CORRIDOR...FOR NOW.
THE QPF IS A MIXED-BAG OF SIGNALS RIGHT NOW. GFS AND EURO ARE
HOLDING ONTO 0.80 OR MORE IN THE NRN HALF OF THE AREA...WITH ONLY
REAL SNOW THERE. THE NAM AND THE SREF MEAN TOTALS THERE ARE ONLY
ABOUT 0.50. WILL CONTINUE WITH THE PARTY LINE OF 8-10 FOR A STORM
TOTAL...BUT REWORKED THE NUMBERS DOWN BARELY AN INCH ON THE WHOLE
SO THE TERRIBLE DARK BLUE OF 10-14 DOES NOT HIT PEOPLE IN THE
FACE. AGAIN...JUST HALF AN INCH TO AN INCH OF A DOWNWARD MOVE ON
THE SNOW. THIS IS DUE TO THE RELATIVELY HIGH UNCERTAINTY AT THIS
RANGE. STILL LOOKS LIKE A SOLID WARNING ANY WAY YOU SLICE IT UP
FOR OUR ENTIRE NRN HALF. SOME PRETTY WICKED SF RATES WILL BE HAD
OVERNIGHT AND VERY EARLY MONDAY IN THE NORTH AND PERHAPS AS FAR S
AS STATE COLLEGE AND SUNBURY BUT MOST LIKELY - THE HEAVIEST SNOW
WILL BE JUST TO THE NORTH OF THOSE TWO CITIES.
PRECIP CUTS OFF PRETTY QUICKLY AFTER 12Z/14Z IN THE CENTRAL COS.
THE EAST MAY SEE PRECIP LINGER INTO THE MID MORNING AS THE COLD
AIR MOVES IN AND TEMPS DROP. AFTER WHAT MAY ONLY BE A BRIEF
BREAK...THE NW WINDS WILL UPSLOPE INTO THE ALLEGHENIES AND
LAURELS. CAA WILL CREATE NUMEROUS SHSN OVER THE WRN HIGH TERRAIN
AND FLURRIES ELSEWHERE. THERE MAY EVEN BE SOME DECENT SHSN AS THE
PRECIP ENDS IN THE SERN THIRD OF THE AREA. YET ANOTHER REASON TO
NOT MONKEY WITH THE WARNINGS/ADVYS JUST YET. IT COULD BE A MESSY
COMMUTE FOR GROUNDHOG MORNING. WINDS WILL GET STRONG AND RATHER
GUSTY - ESP ON THE HILL TOPS AND IN THE SERN THIRD/DOWNSLOPE AREAS
CLOSEST TO THE DEEPENING LOW MOVING OFF THE COAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY
MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD
NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW
ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY
DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP
WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND
LAUREL HIGHLANDS LIKELY NEEDING A WIND CHILL ADVISORY /-15F/ MON
NIGHT INTO EARLY TUE. THIS COULD ADD TO STORM-RELATED
IMPACTS...INCLUDING POTENTIAL FOR PATCHY BLACK ICE.
HIGH PRESSURE WILL BRING COLD BUT GENERALLY QUIET WEATHER INTO
MIDWEEK. A WEAK SYSTEM MOVES THROUGH WED THAT MAY BRING LIGHT
ACCUMS TO THE NW HALF /BEFORE THE SYSTEM DEEPENS MORE RAPIDLY OVER
NEW ENGLAND/...WHICH WILL BE FOLLOWED BY A SHOT OF MORE ARCTIC AIR
AS COLD HIGH PRESSURE BUILDS IN FOR THU INTO FRI - INCLUDING A
RETURN OF BELOW ZERO WIND CHILLS.
TEMPS MODERATE A BIT...BUT REMAIN BELOW NORMAL...ON SAT. ANOTHER
LOW PRESSURE AREA MAY IMPACT THE REGION ON SUNDAY...BUT AT THIS
TIME IT LOOKS TO BE ON THE WEAKER SIDE.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
DETERIORATING FLYING CONDS EXPECTED THIS AFTN AND EVENING...AS LOW
PRES APPROACHES FROM THE MIDWEST...SPREADING SNOW AND LOWERING
CIGS ACROSS CENTRAL PA. AT 17Z...IFR CONDS ALREADY NOTED ACROSS
WESTERN PA. UPSTREAM RADAR RETURNS AND LATEST HRRR OUTPUT SUGGESTS
IFR CONDS WILL DEVELOP AT KAOO/KUNV/KIPT BTWN 19Z-21Z. ACROSS THE
SOUTHEAST COUNTIES...LATEST MDL DATA SUGGESTS A BAND OF LGT
SNOW/VIS REDUCTIONS COULD COME THROUGH BTWN 22Z-01Z AT KMDT/KLNS.
HOWEVER...CONFIDENCE IN IFR CONDS WILL INCREASE MARKEDLY AT
KMDT/KLNS BTWN 03Z-06Z...AS HEAVIEST SNOW ARRIVES.
WARMER AIR WORKING INTO THE STATE WILL CHANGE SNOW TO EITHER RAIN
OR FZRA ACROSS THE SOUTHERN HALF OF THE STATE LATE TONIGHT.
HOWEVER....WIDESPREAD IFR TO LIFR CONDS EXPECTED EVERYWHERE IN
CONTINUING PRECIP AND LOW CIGS RESULTING FROM MOIST SE FLOW
ASCENDING THE HIGHER TERRAIN OF CENTRAL PA. MARGINAL LLWS REMAINS
A POSSIBILITY LATE TONIGHT ACROSS SOUTHERN PA...AS CORE OF STRONG
WINDS ALOFT SLIDES ACROSS THE AREA. HOWEVER...LATEST MODEL
SOUNDINGS SUGGEST MOST PLACES WILL REMAIN JUST BLW CRITERIA.
MARKED IMPROVEMENT IS EXPECTED BTWN 15Z-18Z MONDAY...AS LOW PRES
PASSES EAST OF THE AREA...AND DRIER NW FLOW DEVELOPS. FOCUS WILL
SHIFT TOWARD STRONG GUSTY WINDS MON PM. GUSTS TO ARND 40KTS ARE
POSSIBLE MON AFTN AND EVENING...AS STRENGTHENING STORM SYSTEM
PASSES EAST OF PA.
OUTLOOK...
MON...AM RAIN/SNOW AND LOW CIGS. PM GUSTY NW WINDS.
TUE...NO SIG WX EXPECTED.
WED...AM LGT SNOW POSSIBLE NW MTNS.
THU...AM LGT SNOW POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR PAZ004>006-
010>012-017>019-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY UNTIL 8 AM EST MONDAY FOR PAZ033>036-
064>066.
WINTER STORM WARNING UNTIL 8 AM EST MONDAY FOR PAZ024>028-056-
057-059-063.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1258 PM EST SUN FEB 1 2015
.SYNOPSIS...
LOW PRESSURE WILL CROSS THE CENTRAL MISSISSIPPI RIVER VALLEY
TODAY AND MOVE INTO THE OHIO VALLEY TONIGHT...AND CROSS THE STATE
ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION
ACROSS THE AREA THIS AFTERNOON INTO MONDAY. A PERIOD OF FREEZING
RAIN IS LIKELY ACROSS THE SOUTH AND CENTRAL SECTIONS TONIGHT.
ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY AFTERNOON INTO
TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONLY SOME REALLY PATCHY AND LIGHT SNOW IS FALLING OVER THE WRN
HALF OF THE AREA. BUT SOME MORE-INTENSE BANDS MOVING OVER PBZ/S
AREA AND INTO THE LAURELS ATTM. THESE SHOULD MAKE SOME
ACCUMULATIONIN THE WEST/CENTRAL COS BY MID- AFTERNOON...BUT THE
SUN IS MANAGING TO MAKE A BRIGHT SPOT IN THE CLOUDS OVER STATE
COLLEGE RIGHT NOW. IT IS STILL SNOWING WITH VSBY LT 4SM.
BUT...ANYTHING MORE THAN A FEW TENTHS OF SNOW ACCUM ARE UNLIKELY
BEFORE MID AFTN. MESO MDLS HINT AT A BREAK AFTER A FEW BANDS OF
SNOW SLIDE SW-NE THRU THE AREA THIS AFTN...THEN THE SNOW MOVES
BACK IN AND INTENSIFIES FROM SW-NE THIS EVENING. ALL THIS IS
PRETTY MUCH UNCHANGED.
WITH THAT SAID...
WITH EACH PASSING MODEL CYCLE IT LOOKS LIKE WE WILL GET LESS SNOW
ON THE WHOLE...WHETHER DUE TO LOWER QPF DUE TO ONLY A COUPLE OF
HEAVIER BANDS AND PERHAPS ONLY ONE 3-6 HR PERIOD OF HEAVY SNOW -
OR DUE TO MORE RAIN/MIX OCCURRING IN THE SOUTHERN HALF OF THE
AREA. HOWEVER...IT HAS BARELY STARTED SNOWING. LETS AT LEAST LET
IT START TO PLAY OUT. WILL NOT MAKE ANY TWEAKS TO SNOW OR ICE
ACCUMS OR CHANGES TO HEADLINES AT THIS POINT. BUT THE LATER
UPDATES TODAY MAY JUST FOLLOW THIS MILDER/DRIER TREND IF THE
NEWER GFS AND EC LOOK SIMILARLY MILD AND LESS WET.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
LOW PRESSURE MOVES UP THE OHIO RIVER TONIGHT. BY MONDAY MORNING
IT SHOULD BE OVER KPIT...AND ROLL OVER THE SOUTHERN HALF OF THE
LOCAL AREA. MAIN QPF FALLS IN THE 03Z TO 09Z TIMEFRAME FOR MANY...
AND THIS SIX HOUR PERIOD WILL BE CRITICAL FOR SNOW ACCUMS OVER THE
CENTRAL MOUNTAINS...JUST NORTH OF THE CHANGEOVER ZONE. FASTER/
GREATER MIXING WILL DECREASE SNOW AMOUNTS SUBSTANTIALLY. FOR NOW
HAVE NUDGED THE MIXING ZONE NORTH AND DECREASED SNOW AMOUNTS SOUTH
OF INTERSTATE 80 INTO THE 4-6" RANGE. AS A RESULT...GREATER FZRA
POTENTIAL EXISTS WITH THIS SOLUTION THAN PREVIOUS THINKING.
WHILE THE FARTHER NORTH/WARMER SOLUTION WILL CUT DOWN THE SNOW
AMOUNTS IN THE CENTRAL ZONES...WARNING CRITERIA SNOWFALL IS
EXPECTED NORTH OF INTERSTATE 80. ADVY AND SUB ADVISORY SNOW
AMOUNTS ARE EXPECTED ACROSS THE SOUTHERN THIRD OF CENTRAL PA...
BUT THE CHANCE FOR ICING IS ENOUGH TO WARRANT AT LEAST AN ADVY
FOR THEM.
SFC LOW RAPIDLY TRACKS EAST OF THE AREA BY MIDDAY MONDAY...WITH
COLDER AIR POURING BACK INTO THE COMMONWEALTH ON THE BACKSIDE OF
THE LOW. EXPECT LITTLE IF ANY ADDITIONAL SNOW ACCUMULATION BY MON
AFTERNOON ACROSS THE NORTH. PRECIP WILL HAVE SHUT OFF ACROSS
CENTRAL AND SOUTHERN AREAS BY MIDDAY. SHARPLY COLDER AIR IS POISED
TO OVERSPREAD CENTRAL PA AGAIN ON MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY
MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD
NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW
ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY
DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP
WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND
LAUREL HIGHLANDS LIKELY NEEDING A WIND CHILL ADVISORY /-15F/ MON
NIGHT INTO EARLY TUE. THIS COULD ADD TO STORM-RELATED
IMPACTS...INCLUDING POTENTIAL FOR PATCHY BLACK ICE.
HIGH PRESSURE WILL BRING COLD BUT GENERALLY QUIET WEATHER INTO
MIDWEEK. A WEAK SYSTEM MOVES THROUGH WED THAT MAY BRING LIGHT
ACCUMS TO THE NW HALF /BEFORE THE SYSTEM DEEPENS MORE RAPIDLY OVER
NEW ENGLAND/...WHICH WILL BE FOLLOWED BY A SHOT OF MORE ARCTIC AIR
AS COLD HIGH PRESSURE BUILDS IN FOR THU INTO FRI - INCLUDING A
RETURN OF BELOW ZERO WIND CHILLS.
TEMPS MODERATE A BIT...BUT REMAIN BELOW NORMAL...ON SAT. ANOTHER
LOW PRESSURE AREA MAY IMPACT THE REGION ON SUNDAY...BUT AT THIS
TIME IT LOOKS TO BE ON THE WEAKER SIDE.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
DETERIORATING FLYING CONDS EXPECTED THIS AFTN AND EVENING...AS LOW
PRES APPROACHES FROM THE MIDWEST...SPREADING SNOW AND LOWERING
CIGS ACROSS CENTRAL PA. AT 17Z...IFR CONDS ALREADY NOTED ACROSS
WESTERN PA. UPSTREAM RADAR RETURNS AND LATEST HRRR OUTPUT SUGGESTS
IFR CONDS WILL DEVELOP AT KAOO/KUNV/KIPT BTWN 19Z-21Z. ACROSS THE
SOUTHEAST COUNTIES...LATEST MDL DATA SUGGESTS A BAND OF LGT
SNOW/VIS REDUCTIONS COULD COME THROUGH BTWN 22Z-01Z AT KMDT/KLNS.
HOWEVER...CONFIDENCE IN IFR CONDS WILL INCREASE MARKEDLY AT
KMDT/KLNS BTWN 03Z-06Z...AS HEAVIEST SNOW ARRIVES.
WARMER AIR WORKING INTO THE STATE WILL CHANGE SNOW TO EITHER RAIN
OR FZRA ACROSS THE SOUTHERN HALF OF THE STATE LATE TONIGHT.
HOWEVER....WIDESPREAD IFR TO LIFR CONDS EXPECTED EVERYWHERE IN
CONTINUING PRECIP AND LOW CIGS RESULTING FROM MOIST SE FLOW
ASCENDING THE HIGHER TERRAIN OF CENTRAL PA. MARGINAL LLWS REMAINS
A POSSIBILITY LATE TONIGHT ACROSS SOUTHERN PA...AS CORE OF STRONG
WINDS ALOFT SLIDES ACROSS THE AREA. HOWEVER...LATEST MODEL
SOUNDINGS SUGGEST MOST PLACES WILL REMAIN JUST BLW CRITERIA.
MARKED IMPROVEMENT IS EXPECTED BTWN 15Z-18Z MONDAY...AS LOW PRES
PASSES EAST OF THE AREA...AND DRIER NW FLOW DEVELOPS. FOCUS WILL
SHIFT TOWARD STRONG GUSTY WINDS MON PM. GUSTS TO ARND 40KTS ARE
POSSIBLE MON AFTN AND EVENING...AS STRENGTHENING STORM SYSTEM
PASSES EAST OF PA.
OUTLOOK...
MON...AM RAIN/SNOW AND LOW CIGS. PM GUSTY NW WINDS.
TUE...NO SIG WX EXPECTED.
WED...AM LGT SNOW POSSIBLE NW MTNS.
THU...AM LGT SNOW POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR PAZ004>006-
010>012-017>019-037-041-042-045-046-049>053-058.
WINTER WEATHER ADVISORY UNTIL 8 AM EST MONDAY FOR PAZ033>036-
064>066.
WINTER STORM WARNING UNTIL 8 AM EST MONDAY FOR PAZ024>028-056-
057-059-063.
&&
$$
SYNOPSIS...DANGELO/DEVOIR
NEAR TERM...DANGELO
SHORT TERM...DEVOIR
LONG TERM...RXR
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1225 PM CST SUN FEB 1 2015
.DISCUSSION...
UPDATED FOR 18Z AVIATION DISCUSSION
&&
.PREV DISCUSSION... /ISSUED 948 AM CST SUN FEB 1 2015/
UPDATE...
SHOWERS CONTINUE ACROSS MUCH OF THE MIDSOUTH THIS MORNING. THE
SHOWERS ARE OCCURRING AHEAD OF A LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT. BACK EDGE OF SHOWERS HAVE ALREADY PUSHED
EAST OF RANDOLPH...LAWRENCE...CLAY AND GREENE COUNTIES IN
NORTHEAST ARKANSAS. MODELS INDICATE BACK EDGE WILL BE EAST OF THE
MISSISSIPPI RIVER BY NOON. WILL UPDATE TO TRIM POPS ACCORDINGLY.
STILL CAN/T RULE OUT ISOLATED SHOWERS POPPING UP WEST OF THE RIVER BUT
BULK OF RAIN WILL BE DONE WITH. THINK THE ONLY LOCATIONS WITH
CHANCES OF THUNDER WILL BE ACROSS NORTHEAST MISSISSIPPI AS PRECIP
IS MOVING EAST SO FAST.
MEANWHILE...COLD FRONT HAS JUST PUSHED INTO WESTERN ARKANSAS SO
THERE WILL BE A COUPLE OF HOURS OF NO PRECIP AND WARM AIR
ADVECTION OCCURRING ACROSS NE ARKANSAS THAT WILL NEED TO ALSO BUMP
UP HIGHS TO THE MID 50S.
KRM
DISCUSSION... /ISSUED 430 AM CST SUN FEB 1 2015/
AN ACTIVE WEATHER PATTERN CAN BE EXPECTED FOR THE FIRST WEEK OF
FEBRUARY ACROSS THE MIDSOUTH. EARLY THIS MORNING...SOUTHEAST WINDS
WERE PUSHING MILD AIR INTO THE REGION WITH TEMPERATURES IN SOME
LOCATIONS WARMER THAN THEY WERE DURING THE DAY YESTERDAY. THE
LOWER LEVELS WERE VERY DRY ACROSS MUCH OF THE AREA WITH SURFACE
DEW POINTS IN THE TEENS ALONG THE TN RIVER VALLEY. A WARM FRONT
WAS PUSHING TOWARD THE MIDSOUTH FROM THE SOUTHWEST WITH WIDESPREAD
SHOWERS...THE RAIN WAS HAVING A DIFFICULT TIME REACHING THE GROUND
IN OUR FORECAST AREA WITH THE DRY LOW LEVELS. SURFACE LOW PRESSURE
WAS DEVELOPING OVER THE CENTRAL PLAINS WITH MUCH COLDER AIR
LOCATED ACROSS THE NORTHERN PLAINS PUSHING SOUTHWARD BEHIND THE
LOW.
NOT MUCH CHANGE FROM THE EARLIER FORECAST. AS A UPPER LEVEL TROUGH
DIGS INTO THE MIDDLE MS RIVER VALLEY TODAY...THE SURFACE LOW WILL
STRENGTHEN TO NEAR 1000 MB AND BE LOCATED OVER SOUTHERN IN BY SUNSET.
A COLD FRONT TRAILING SOUTHWESTWARD FROM THE LOW WILL APPROACH
EASTERN AR BY NOON AND MOVE RAPIDLY TO NEAR THE TN RIVER AND THE MS /
AL BORDER BY SUNSET. SHOWERS WILL QUICKLY SPREAD ACROSS THE MIDSOUTH
THIS MORNING AHEAD OF THIS SYSTEM AS UPPER LIFT INCREASES
DRAMATICALLY AND THE LOWER LEVELS BECOME SATURATED. BASED ON THE
FORECAST ELEVATED INSTABILITY...ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG AND SOUTH OF INTERSTATE 40. ALSO...SOME SURFACE BASED
INSTABILITY MAY PUSH INTO NORTH MS DURING THE DAY. THE MODELS
INCLUDING THE HRRR AND RAP ARE SHOWING THE RAIN BEGINNING TO PUSH OUT
OF PORTIONS OF NORTHEAST AR AND PORTIONS OF THE MO BOOTHEEL BY EARLY
AFTERNOON...SO BEGAN TO SHOW THE POPS DECREASING FROM THE WEST AT
THIS TIME.
RAIN IS FORECAST TO QUICKLY END FROM THE WEST EARLY THIS EVENING.
LATEST MODELS ARE NOT SHOWING MUCH IF ANY PRECIP ONCE TEMPERATURES
BECOME COLD ENOUGH FOR SNOW...BUT DID CONTINUE TO MENTION A SLIGHT
CHANCE OF FLURRIES AFTER MIDNIGHT IN ASSOCIATION WITH A TRAILING
UPPER LEVEL TROUGH. OTHERWISE...STRONG AND GUSTY NORTHWEST WINDS
WILL PUSH MUCH COLDER AIR INTO THE AREA WITH WIND CHILL READINGS
DROPPING TO BETWEEN 10 AND 20 DEGREES AFTER MIDNIGHT.
MONDAY WILL BE A VERY COLD DAY AS MODIFIED ARCTIC AIR SETTLES OVER
THE MIDSOUTH. HIGHS WILL ONLY BE IN THE 30S WITH SOME LOCATIONS
NEAR THE MO AND KY BORDERS REMAINING A LITTLE BELOW FREEZING. CLOUDS
ARE EXPECTED TO BEGIN CLEARING BY AFTERNOON. MONDAY NIGHT WILL
SEE LOW TEMPERATURES DIP INTO THE LOWER AND MIDDLE 20S.
HIGH PRESSURE WILL MOVE TO ALONG THE ATLANTIC COAST BY LATE TUESDAY
WITH WINDS TURNING TO THE SOUTH ACROSS THE MIDSOUTH. THIS WILL
ALLOW TEMPERATURES TO WARM TO BETWEEN THE MIDDLE 40S AND LOWER 50S
DURING THE AFTERNOON WITH ABUNDANT SUNSHINE.
ATTENTION TURNS TO OUR THE NEXT WEATHER SYSTEM WEDNESDAY...AN
UPPER LOW OVER TX IN THE SOUTHERN STREAM. THE UPPER LOW IS
FORECAST TO BECOME AN OPEN TROUGH AS IT MOVES INTO THE WESTERN GULF.
SURFACE LOW PRESSURE WILL DEVELOP OVER THE WESTERN GULF WEDNESDAY AS
AN ARCTIC FRONT APPROACHES THE MIDSOUTH FROM THE NORTH LATE IN THE
DAY. LOOKS LIKE THE MIDSOUTH WILL BE BETWEEN THESE TWO SYSTEMS
WEDNESDAY WITH MOST RAIN BEING TO OUR SOUTH ALONG THE NORTHWEST
GULF COAST.
THE WEATHER BECOMES INTERESTING AND COMPLICATED WEDNESDAY NIGHT AND
THURSDAY...ALTHOUGH THE GFS AND ECMWF STILL ARE NOT IN GOOD
AGREEMENT. AS THE UPPER LEVEL TROUGH AND ASSOCIATED SURFACE LOW TO
OUR SOUTH MOVE EASTWARD WITH THE UPPER TROUGH WEAKENING...IT LOOKS
LIKE MOST OF THE RAIN WITH THIS SYSTEM WILL STAY TO OUR SOUTH
POSSIBLY MOVING INTO PORTIONS OF NORTH MS. MEANWHILE...MODELS SHOW
THE ARCTIC FRONT CONTINUING TO PUSH SOUTHWARD THROUGH THE MIDSOUTH.
THE GFS IS FASTER WITH THE COLDER AIR THAN THE ECMWF. SOME LIGHT RAIN
IS INDICATED WITH THIS FRONT WEDNESDAY NIGHT...CHANGING TO LIGHT
SNOW FROM THE NORTH WITH SOME SLEET OR FREEZING POSSIBLE IN THE
TRANSITION ZONE. FOR THURSDAY...THE ECMWF SHOWS THE LIGHT WINTRY
PRECIP MOVING FURTHER SOUTH AS THE ARCTIC FRONT CONTINUES SOUTH...
BUT THE ECMWF QUICKLY MOVES THE PRECIP OUT OF THE AREA BY
AFTERNOON. ON THE OTHER HAND...THE GFS SHOWS A STRONGER UPPER LEVEL
TROUGH FROM THE NORTHWEST INTERACTING WITH THE COLD AIR THURSDAY
WHICH COULD LEAD TO SOME LIGHT SNOW ACCUMULATIONS. FOR NOW...LOTS OF
UNCERTAINTY DURING THIS TIME FRAME. WILL HAVE TO SEE HOW THE MODELS
COME TOGETHER ON THIS SITUATION REGARDING PRECIP IF ANY AND PRECIP
TYPES.
JCL
&&
.AVIATION...
18Z TAF CYCLE
MAINLY IFR CONDS PREVAIL ACROSS THE TERMINALS ATTM AS SHRAS
CONTINUE TO MOVE THROUGH THE AREA IN ADVANCE OF APPROACHING COLD
FRONT. COLD FRONT WILL PUSH THROUGH LATER THIS AFTERNOON AND A FEW
TSRAS ARE POSSIBLE...MAINLY AT KTUP. SHRAS WILL TAPER OFF EARLY
THIS EVENING AND CIGS WILL LIFT TO MVFR...BRIEF VFR POSSIBLE AT
KMEM. GUSTY SOUTH WINDS WILL VEER TO WEST WITH COLD FRONT PASSAGE AND
NW POST FRONTAL...REMAINING GUSTY.
SJM
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS EL PASO TX/SANTA TERESA NM
300 PM MST SUN FEB 1 2015
.SYNOPSIS...
A WEAK COLD FRONT HAS MOVED INTO THE AREA AND WILL HELP LOWER
OVERNIGHT TEMPERATURES TONIGHT. AT THE SAME TIME PATCHY FOG IS
EXPECTED TO AGAIN DEVELOP JUST BEFORE SUNRISE THANKS TO LEFT OVER
MOISTURE FROM RECENT RAINS. ONCE THE FOG BURNS OFF MOSTLY SUNNY
CONDITIONS WILL TAKE OVER AND DOMINATE FOR THE REST OF THE WEEK
AHEAD. TEMPS WILL CLIMB TO NEAR NORMAL MONDAY AND SHOULD BE AS MUCH
AS 10 DEGREES ABOVE NORMAL BY THE END OF THE WEEK.
&&
.DISCUSSION...
WITH THE UPPER LOW NOW WELL SOUTH OF THE THE REGION NORTHWESTERLY
FLOW ALOFT HAS TAKEN OVER. A WEAK SHORTWAVE EMBEDDED IN THIS FLOW IS
CURRENTLY PUSHING A WEAK BACK DOOR COLD FRONT THROUGH THE AREA AND
WILL RESULT IN EASTERLY SURFACE FLOW DURING THE OVERNIGHT HOURS.
GIVEN THE FACT THAT THE BOUNDARY LAYER HAS NOT DRIED MUCH IN THE
PAST 24 HOURS...ENOUGH RESIDUAL MOISTURE REMAINS TO HELP GENERATE
ADDITIONAL LOW CLOUDS OVER OUR EASTERN ZONES TONIGHT IN CONJUNCTION
WITH THE UPSLOPE COMPONENT OF THE EASTERLY SURFACE FLOW. IN ADDITION
BOTH THE HI RES WRF AND THE LATEST HRRR SHOW DEW PT DEPRESSIONS
DROPPING TO NEAR ZERO JUST PRIOR TO SUNRISE FOR LOWLAND LOCATIONS OF
SOUTHCENTRAL NEW MEXICO AND FAR WEST TEXAS. IT LOOKS AS IF PATCHY
DENSE FOG WILL FORM ONCE AGAIN IN MANY OF THE SAME AREAS THAT SAW
THE FOG THIS MORNING.
FOG AND LOW CLOUDS SHOULD MIX OUT FAIRLY QUICKLY MONDAY MORNING
AFTER SUNRISE. THIS WILL BE FOLLOWED BY MOSTLY CLEAR SKIES FOR
SEVERAL DAYS TO COME AS RIDGING DEVELOPS ACROSS THE SOUTHWESTERN
STATES. THE END RESULT WILL BE A WARMING TREND THAT SHOULD CARRY
THROUGH MUCH OF THE WEEK AHEAD. A SHORTWAVE WILL ROUND THE RIDGE AND
PASS TO OUR NORTHEAST WEDNESDAY RESULTING IN LEE TROUGHING AND A
SLIGHT UPTICK IN WESTERLY SURFACE WIND SPEEDS. THIS WILL BE FOLLOWED
BY A WEAK BACK DOOR COLD FRONT WEDNESDAY NIGHT. THIS FRONTAL PUSH
WILL ONLY SERVE TO STALL THE WARMING TREND BY ABOUT A DAY OR SO AS
THE RIDGE ALOFT WILL THEN MIGRATE OVERHEAD AS WE APPROACH THE
WEEKEND. IN GENERAL HIGH TEMPS SHOULD RUN A GOOD 10 DEGREES ABOVE
NORMAL BY FRIDAY AND SATURDAY WITH ONLY OCCASIONAL HIGH CLOUDS
PASSING BY.
&&
.AVIATION...VALID 02/00Z-03/00Z...
SATELLITE IMAGERY INDICATES A WEAK BACKDOOR FRONT PUSHING INTO THE
EAST SLOPES OF THE SACRAMENTO MOUNTAINS...DOWN TOWARDS THE EL
PASO/HUDSPETH COUNTY LINE. UPSLOPE LOW CLOUDS/FOG ARE ALREADY IN
PLACE ALONG THE EAST SLOPES OF THE SACRAMENTO MOUNTAINS...AND WILL
LIKELY SPREAD INTO PARTS OF EASTERN HUDSPETH COUNTY LATER TONIGHT.
ELSEWHERE...LIGHT NORTHERLY WINDS WILL BECOME VARIABLE OVERNIGHT
FROM THE TULAROSA BASIN AND ALL POINTS WEST. DEWPOINTS IN THE UPPER
30S TO AROUND 40 INDICATE THAT THE BOUNDARY LAYER HAS NOT MIXED OUT
MUCH OF THE LOW LEVEL MOISTURE TODAY. LACK OF ANY LOW LEVEL DRY
ADVECTION AND IDEAL CONDITIONS FOR RADIATIVE COOLING SUGGEST AREAS
OF FOG WILL RE-DEVELOP AGAIN TOWARDS DAWN. IT IS DIFFICULT TO
PINPOINT THE WORST SPOTS. PORTIONS OF SIERRA COUNTY ARE PERHAPS LESS
FAVORED GIVEN THEY ARE THE RELATIVE DRY SPOT AT THE MOMENT WITH
DEWPOINTS IN THE LOW 30S. VARIOUS MODELS INCLUDING WRF-NMM BROADLY
SUGGEST AN ARC FROM DMN-LRU INTO SOUTHERN SIERRA COUNTY MOST
FAVORED. GENERALLY WENT PESSIMISTIC WITH THE TAFS WITH LIFR VERTICAL
VISBYS AT DMN/LRU. WENT SLIGHTLY DENSER WITH THE FOG (1/4SM IN
TEMPO GROUPS) AT LRU WITH LIGHT SE FLOW POSSIBLE...WHICH FAVORS FOG
ALONG THE WEST MESA. LOW CONFIDENCE FOR ELP AND TCS BUT 1-3SM IN BR
IS POSSIBLE.
OTHERWISE...VFR CONDITIONS AND LIGHT WINDS TO PREVAIL AFTER 18Z.
&&
.FIRE WEATHER...
OBS SHOW LIGHT NORTHERLY WINDS HAVE PUSHED ACROSS MOST OF THE
AREA... WHILE A WEAK BACKDOOR FRONT MOST EVIDENT ON VISIBLE
SATELLITE IMAGERY...IS BRINGING LIGHT EASTERLY WINDS TO THE EAST
SLOPES OF THE SACRAMENTO MOUNTAINS AND PORTIONS OF THE OTERO MESA
AND HUDSPETH COUNTY. THIS WILL RESULT IN SOME UPSLOPE CLOUDS AND FOG
EAST OF THE OTERO MESA RIM AND IN THE SACRAMENTO MOUNTAINS
OVERNIGHT.
ELSEWHERE IN SW NEW MEXICO...MOIST BOUNDARY LAYER CONDITIONS WITH
LACK OF DRY ADVECTION COUPLED WITH WINDS BECOMING LIGHT AND VARIABLE
AFTER MIDNIGHT WILL RESULT IN SOME FOG DEVELOPING AGAIN TOWARDS
DAWN. RH RECOVERY WILL BE EXCELLENT EVEN WITHOUT FOG AS MAX RH
VALUES WILL BE AROUND 80 PERCENT AT THE LOWEST...LIKELY IN PARTS OF
SIERRA COUNTY WHERE BL MIXING WAS MAXIMIZED TODAY.
EXPECT A WARMING/DRYING TREND THROUGH THE WEEK AHEAD. TEMPERATURES
WILL CLIMB TO AROUND 5-8 DEGREES ABOVE AVERAGE BY WEDNESDAY. LIGHT
WINDS AND SHALLOW MIXING WILL LIMIT VENT RATES MONDAY...ESPECIALLY
IN THE LOWLANDS...WITH SOME IMPROVEMENTS ON TUESDAY AND WEDNESDAY
EXCEPT IN THE RIO GRANDE VALLEY.
&&
.PRELIMINARY POINT TEMPS/POPS...
EL PASO 35 61 37 65 39 / 0 0 0 0 0
SIERRA BLANCA 34 60 37 63 37 / 0 0 0 0 0
LAS CRUCES 32 58 35 62 37 / 0 0 0 0 0
ALAMOGORDO 30 57 32 61 36 / 0 0 0 0 0
CLOUDCROFT 23 44 26 44 30 / 0 0 0 0 0
TRUTH OR CONSEQUENCES 34 57 37 61 36 / 0 0 0 0 0
SILVER CITY 29 58 34 63 36 / 0 0 0 0 0
DEMING 31 62 32 64 34 / 0 0 0 0 0
LORDSBURG 32 61 33 62 35 / 0 0 0 0 0
WEST EL PASO METRO 38 61 39 66 41 / 0 0 0 0 0
DELL CITY 29 58 32 62 33 / 0 0 0 0 0
FORT HANCOCK 37 63 37 66 38 / 0 0 0 0 0
LOMA LINDA 34 56 35 60 40 / 0 0 0 0 0
FABENS 32 60 35 65 37 / 0 0 0 0 0
SANTA TERESA 33 60 34 64 38 / 0 0 0 0 0
WHITE SANDS HQ 33 59 36 64 39 / 0 0 0 0 0
JORNADA RANGE 28 58 31 61 34 / 0 0 0 0 0
HATCH 30 63 33 67 34 / 0 0 0 0 0
COLUMBUS 34 62 35 63 37 / 0 0 0 0 0
OROGRANDE 33 58 36 64 39 / 0 0 0 0 0
MAYHILL 26 55 32 56 36 / 0 0 0 0 0
MESCALERO 24 50 27 51 32 / 0 0 0 0 0
TIMBERON 28 52 32 52 35 / 0 0 0 0 0
WINSTON 32 54 35 58 34 / 0 0 0 0 0
HILLSBORO 33 57 38 60 39 / 0 0 0 0 0
SPACEPORT 32 60 33 63 36 / 0 0 0 0 0
LAKE ROBERTS 27 57 33 61 34 / 0 0 0 0 0
HURLEY 29 56 33 60 35 / 0 0 0 0 0
CLIFF 27 60 30 62 32 / 0 0 0 0 0
MULE CREEK 23 58 27 61 31 / 0 0 0 0 0
FAYWOOD 33 55 36 60 38 / 0 0 0 0 0
ANIMAS 31 65 32 65 36 / 0 0 0 0 0
HACHITA 29 65 31 65 34 / 0 0 0 0 0
ANTELOPE WELLS 29 65 30 64 34 / 0 0 0 0 0
CLOVERDALE 34 63 33 64 37 / 0 0 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
LANEY/HARDIMAN
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
505 PM CST SUN FEB 1 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 220 PM CST SUN FEB 1 2015
CONCERNS THROUGH MONDAY...
1. DIMINISHING SNOW/BLOWING SNOW THROUGH THE EVENING
2. NEED FOR WIND CHILL ADVISORY LATE TONIGHT/MONDAY MORNING
3. HIGHS MONDAY
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE WESTERN U.S....A SHORTWAVE TOPPING THE RIDGE
COMING INTO BRITISH COLUMBIA...A DEEP TROUGH OVER THE CENTRAL PLAINS
INTO SOUTHERN PORTIONS OF THE FORECAST AREA...AND A SHORTWAVE OVER
THE EASTERN DAKOTAS. MID-LEVEL FRONTOGENESIS ASSOCIATED ON THE NORTH
SIDE OF THE DEEP TROUGH CONTINUES TO BRING SNOW TO THE SOUTHEASTERN
2/3 OF THE FORECAST AREA. OVER THE NORTHWEST 1/3 AND THROUGH THE
REST OF MINNESOTA AND NORTHERN WI...DRIER AND COLDER AIR CONTINUES
TO ADVECT SOUTHWARD ON A BRISK NORTHERLY BREEZE. NUMEROUS SITES
NORTH OF I-94 REPORTING SURFACE DEWPOINTS BELOW ZERO...AND AS MUCH
AS 20 BELOW IN NORTHERN MN. TEMPERATURES TOO WERE IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO NORTH OF I-94. CLEARING SKIES REFLECT
THE DRIER...COLDER AIR. MAIN 1004MB SURFACE LOW ASSOCIATED WITH THE
TROUGH WELL TO OUR SOUTHEAST...JUST EAST OF LINCOLN IL. HOWEVER...A
TIGHT PRESSURE GRADIENT EXISTS NORTH OF THIS LOW KEEPING THE BRISK
NORTH BREEZE GOING...WITH A 1034MB HIGH OVER THE DAKOTAS.
THE SNOW REMAINS ON TRACK TO DIMINISH NORTHWEST TO SOUTHEAST THROUGH
THE REST OF THIS AFTERNOON INTO EARLY THIS EVENING. BY 00Z...GOOD
MODEL AGREEMENT EXISTS FOR SNOW SOUTHEAST OF A LINE FROM OELWEIN TO
TOMAH...AND THEN OUT OF THE FORECAST AREA BY 03Z. ALTHOUGH SNOW IS
DIMINISHING...WINDS LOOK TO REMAIN BRISK THROUGH AT LEAST A GOOD
PORTION OF THE EVENING. 925MB WINDS AT 00Z RANGE FROM 25-35KT...
DROPPING TO 10-25KT AT 06Z. THESE GUSTY WINDS SHOULD KEEP
SOME BLOWING AND DRIFTING SNOW GOING AT EXPOSED LOCATIONS...EVEN
WHEN THE SNOW ENDS...THUS HAVE DECIDED TO HOLD OFF CANCEL ANY
HAZARDS AT THIS TIME. HOWEVER...ITS POSSIBLE SOME AREAS MAY
GET CANCELLED EARLY OVER THE NEXT FEW HOURS SEEING DODGE CENTER HAS
IMPROVED TO 10 MILE VISIBILITY ALREADY.
DURING THE OVERNIGHT HOURS...THE SHORTWAVE CURRENTLY IN THE EASTERN
DAKOTAS IS PROGGED TO CROSS THE FORECAST AREA. ALTHOUGH NO
PRECIPITATION PRODUCTION IS EXPECTED WITH THIS SHORTWAVE DUE TO
PLENTIFUL DRY AIR AROUND AND AHEAD OF IT...THE SHORTWAVE WILL HELP
TO BRING THE DAKOTAS SURFACE RIDGE INTO THE FORECAST
AREA...THUS DIMINISHING THE WINDS AND CLEARING THE SKIES OUT. WITH
THE FRESH SNOW COVER...TEMPERATURES COULD REALLY PLUMMET...AIDED TOO
BY 925MB TEMPS FALLING TO -16 TO -18C. WOULD NOT BE SURPRISED TO SEE
A FEW READINGS OF 10 BELOW...WHICH WOULD MOST LIKELY OCCUR NEAR
AUSTIN MN AND IN TAYLOR COUNTY WI. DESPITE THE COLD READINGS...WIND
CHILLS SHOULD STAY UP JUST ABOVE THE -20F THRESHOLD FOR AN ADVISORY.
A MUCH QUIETER BUT COLD DAY ON TAP FOR MONDAY AS THE SURFACE RIDGE
CROSSES THE FORECAST AREA. THE SURFACE RIDGE GRADUALLY CROSSES THE
FORECAST AREA...WITH MOSTLY SUNNY SKIES TO START. SHOULD SEE SOME
INCREASE IN CLOUDS IN THE AFTERNOON AS THE SHORTWAVE COMING INTO
BRITISH COLUMBIA DROPS DOWN INTO THE SIOUX FALLS AREA BY 00Z. 925MB
TEMPS DONT START WARMING UNTIL LATE IN THE DAY...AND WITH FRESH
SNOW...HIGHS ONLY LOOK TO TOP OUT IN THE LOW TO MID TEENS. ITS
POSSIBLE SOME LOCATIONS IN NORTHEAST IOWA ONLY REACH THE SINGLE
DIGITS ABOVE ZERO AS SUGGESTED BY THE 01.12Z ECMWF/CANADIAN.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 220 PM CST SUN FEB 1 2015
LONG TERM CONCERNS...
1. BRIEF LIGHT SNOW MAKER MONDAY EVENING FOR MAINLY NORTHEAST IOWA
2. ANOTHER LIGHT SNOW MAKER FOR TUESDAY AFTERNOON/EVENING...MAINLY
SOUTH OF I-90
3. POSSIBLE WIND CHILL ADVISORY FOR THURSDAY MORNING
4. POSSIBILITY FOR A BRIEF WARM UP...BUT BREEZY...FOR FRIDAY INTO
SATURDAY.
SHORTWAVE OVER BRITISH COLUMBIA IS PROGGED TO DIG INTO SOUTHEAST
IOWA AND NORTHEAST MO BY 06Z TUESDAY. THIS TRACK HAS TRENDED
SOUTHWEST SLIGHTLY OVER THE PAST FEW DAYS. DESPITE ITS POTENT
NATURE/LOOK...MODELS DO NOT PRODUCE MUCH QPF WITH IT DUE TO
DRY AIR IN PLACE FROM MONDAY...WITH THE GFS ENTIRELY DRY. GIVEN ITS
STRENGTH FEEL THE NEED TO INCLUDE A LOW PRECIPITATION CHANCE FOR
MONDAY EVENING...SIMILAR TO THE PREVIOUS FORECAST. HOWEVER...WITH
THE SOUTHWEST TREND IN THE GUIDANCE...SHIFTED THE CHANCES A LITTLE
MORE SOUTHWEST AS WELL. SHOULD ANY SNOW OCCUR...MAYBE A FEW TENTHS
ACCUMULATE.
AFTER A QUIET OVERNIGHT MONDAY NIGHT INTO TUESDAY MORNING...POSSIBLY
A BIT COOL WITH A SURFACE RIDGE CROSSING...ANOTHER SHORTWAVE TROUGH
COMING TROUGH NORTHWEST FLOW IS PROGGED TO AFFECT THE AREA TUESDAY
AFTERNOON AND EVENING. THIS SHORTWAVE...ALTHOUGH WEAKER
COMPARED TO THE PREVIOUS ONE...HAS A LITTLE MORE MOISTURE TO WORK
WITH AND A STRONGER MID LEVEL FRONTOGENESIS ZONE. AS SUCH...01.12Z
NAM/GFS/ECMWF/CANADIAN ALL DEVELOP PRECIPITATION...WITH SOME EVEN
SHOWING POTENTIAL TO EXCEED 0.10 OF QPF IN 6 HOURS. SOME
TRACK ISSUES AGAIN EXIST...WITH THE STRONGEST CONSENSUS FOR THE SNOW
TO MOVE THROUGH LOCATIONS SOUTH OF I-90. UNLESS THE SHORTWAVE
BECOMES STRONGER IN LATER RUNS...FEEL THE PLACEMENT OF THIS SNOW
SHOULD STAY PERSISTENT. THUS...DID RAISE PRECIPITATION CHANCES
TOWARDS 50 ACROSS NORTHEAST IA/FAR SOUTHWEST WI. MAY END UP
ACCUMULATING 1-2 INCHES. SOME CONCERN TOO FOR THE PRECIPITATION TO
END AS FREEZING DRIZZLE AS ICE IS LOST ALOFT...BUT ITS VERY
POSSIBLE THE PRECIPITATION ENDS TOO ONCE WE LOSE THE ICE.
THEREFORE...HAVE YET TO INTRODUCE THIS INTO THE FORECAST.
SOMETHING TO MONITOR.
A STRONG UPPER TROUGH DROPS INTO THE REGION ON WEDNESDAY. THERE
COULD BE A LITTLE LIGHT SNOW IN OUR SOUTH DURING THE AFTERNOON WITH
ANOTHER FRONTOGENESIS BAND SETTING UP ACROSS IOWA AND ILLINOIS.
HOWEVER...THE MORE SIGNIFICANT PART IS THE ARCTIC AIR ACCOMPANY THE
UPPER TROUGH. 925MB TEMPS PLUMMET FROM -10 TO -13C AT 12Z WEDNESDAY
TO -18 TO -20C AT 12Z THURSDAY. A SOMEWHAT BRISK NORTHERLY BREEZE IS
PROGGED WEDNESDAY AFTERNOON AND EVENING BEFORE DIMINISHING
OVERNIGHT. THIS DIMINISHING COULD KEEP US JUST OUT OF A WIND CHILL
ADVISORY NEED FOR THURSDAY MORNING...BUT TEMPERATURES WOULD TANK
INSTEAD...ESPECIALLY IF SKIES ARE CLEAR. STAYED ON THE COOLER SIDE
OF GUIDANCE FOR LOWS WEDNESDAY NIGHT GIVEN THIS REGIME AND
THINKING ARCTIC AIR COMING IN WILL CLEAR SKIES OUT.
THE UPPER TROUGH IS FAST MOVING SUCH THAT WEAK UPPER RIDGING COMES
IN BY THURSDAY AFTERNOON...WITH NORTHWEST FLOW PERSISTING BEYOND
INTO SUNDAY. THUS...AFTER THE COLD START THURSDAY MORNING WE WILL BE
ON THE WARMING TREND HEADING INTO FRIDAY AND SATURDAY. STILL A LOT
OF SPREAD AMONGST ECMWF GUIDANCE REGARDING THE HIGHS FRIDAY AND
SATURDAY...BUT GENERAL TREND SHOULD BRING HIGHS BACK TO NORMAL.
GFS/ECMWF 925MB WINDS ALSO INCREASE TO 20-40KT ON FRIDAY...THUS
SUGGESTING IT COULD BE A BIT BREEZY. SOMETHING WELL HAVE TO WATCH
HEADING INTO NEXT WEEKEND IS A FRONTOGENETIC ZONE DROPPING SOUTHWEST
THROUGH THE FORECAST AREA. ACTUAL POSITION AND TIMING HAS VARIED
SOMEWHAT...REQUIRING LOW CHANCES OF PRECIPITATION THROUGH THE
WEEKEND. NEVERTHELESS...COULD SEE A COUPLE INCHES OF SNOW
ACCUMULATION. COOLER AIR FOLLOWS IN THE WAKE OF THIS ZONE FOR
SUNDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 505 PM CST SUN FEB 1 2015
THE SNOW HAS SHIFTED EAST OF KRST/KLSE AT EARLY EVENING...WITH
LATEST OBS INDICATING THAT BLSN IS BECOMING LESS OF A CONCERN AT
KRST. CIGS HAVE ALREADY IMPROVED TO VFR AT THE TAF SITES TOO...AND
EXPECT VFR CONDITIONS TO PREVAIL TONIGHT THROUGH MONDAY.
WINDS WILL BE ON A DECREASING TREND THIS EVENING AS THE LOW EXITS
EAST...HIGH PRESSURE APPROACHES...AND THE PRESSURE GRADIENT
SLACKENS. VARIABLE WINDS IN THE MORNING WILL BECOME SOUTHERLY BY
18Z MONDAY.
UPPER LEVEL SHORTWAVE TROUGH SLATED TO SPIN ACROSS IOWA MONDAY
NIGHT...LIKELY BRINGING A LITTLE LIGHT SNOW. CURRENT TRACK WOULD
KEEP THE BULK OF ANY -SN SOUTHWEST OF KRST/KLSE...BUT WOULD BRING AT
LEAST SOME LOW/MID LEVEL CIGS. MVFR IS POSSIBLE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR WIZ054-061.
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
WIZ041>044-053-055.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
MNZ086>088-094>096.
IA...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR IAZ008>011-
018-019-029-030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
220 PM CST SUN FEB 1 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 220 PM CST SUN FEB 1 2015
CONCERNS THROUGH MONDAY...
1. DIMINISHING SNOW/BLOWING SNOW THROUGH THE EVENING
2. NEED FOR WIND CHILL ADVISORY LATE TONIGHT/MONDAY MORNING
3. HIGHS MONDAY
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE WESTERN U.S....A SHORTWAVE TOPPING THE RIDGE
COMING INTO BRITISH COLUMBIA...A DEEP TROUGH OVER THE CENTRAL PLAINS
INTO SOUTHERN PORTIONS OF THE FORECAST AREA...AND A SHORTWAVE OVER
THE EASTERN DAKOTAS. MID-LEVEL FRONTOGENESIS ASSOCIATED ON THE NORTH
SIDE OF THE DEEP TROUGH CONTINUES TO BRING SNOW TO THE SOUTHEASTERN
2/3 OF THE FORECAST AREA. OVER THE NORTHWEST 1/3 AND THROUGH THE
REST OF MINNESOTA AND NORTHERN WI...DRIER AND COLDER AIR CONTINUES
TO ADVECT SOUTHWARD ON A BRISK NORTHERLY BREEZE. NUMEROUS SITES
NORTH OF I-94 REPORTING SURFACE DEWPOINTS BELOW ZERO...AND AS MUCH
AS 20 BELOW IN NORTHERN MN. TEMPERATURES TOO WERE IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO NORTH OF I-94. CLEARING SKIES REFLECT
THE DRIER...COLDER AIR. MAIN 1004MB SURFACE LOW ASSOCIATED WITH THE
TROUGH WELL TO OUR SOUTHEAST...JUST EAST OF LINCOLN IL. HOWEVER...A
TIGHT PRESSURE GRADIENT EXISTS NORTH OF THIS LOW KEEPING THE BRISK
NORTH BREEZE GOING...WITH A 1034MB HIGH OVER THE DAKOTAS.
THE SNOW REMAINS ON TRACK TO DIMINISH NORTHWEST TO SOUTHEAST THROUGH
THE REST OF THIS AFTERNOON INTO EARLY THIS EVENING. BY 00Z...GOOD
MODEL AGREEMENT EXISTS FOR SNOW SOUTHEAST OF A LINE FROM OELWEIN TO
TOMAH...AND THEN OUT OF THE FORECAST AREA BY 03Z. ALTHOUGH SNOW IS
DIMINISHING...WINDS LOOK TO REMAIN BRISK THROUGH AT LEAST A GOOD
PORTION OF THE EVENING. 925MB WINDS AT 00Z RANGE FROM 25-35KT...
DROPPING TO 10-25KT AT 06Z. THESE GUSTY WINDS SHOULD KEEP
SOME BLOWING AND DRIFTING SNOW GOING AT EXPOSED LOCATIONS...EVEN
WHEN THE SNOW ENDS...THUS HAVE DECIDED TO HOLD OFF CANCEL ANY
HAZARDS AT THIS TIME. HOWEVER...ITS POSSIBLE SOME AREAS MAY
GET CANCELLED EARLY OVER THE NEXT FEW HOURS SEEING DODGE CENTER HAS
IMPROVED TO 10 MILE VISIBILITY ALREADY.
DURING THE OVERNIGHT HOURS...THE SHORTWAVE CURRENTLY IN THE EASTERN
DAKOTAS IS PROGGED TO CROSS THE FORECAST AREA. ALTHOUGH NO
PRECIPITATION PRODUCTION IS EXPECTED WITH THIS SHORTWAVE DUE TO
PLENTIFUL DRY AIR AROUND AND AHEAD OF IT...THE SHORTWAVE WILL HELP
TO BRING THE DAKOTAS SURFACE RIDGE INTO THE FORECAST
AREA...THUS DIMINISHING THE WINDS AND CLEARING THE SKIES OUT. WITH
THE FRESH SNOW COVER...TEMPERATURES COULD REALLY PLUMMET...AIDED TOO
BY 925MB TEMPS FALLING TO -16 TO -18C. WOULD NOT BE SURPRISED TO SEE
A FEW READINGS OF 10 BELOW...WHICH WOULD MOST LIKELY OCCUR NEAR
AUSTIN MN AND IN TAYLOR COUNTY WI. DESPITE THE COLD READINGS...WIND
CHILLS SHOULD STAY UP JUST ABOVE THE -20F THRESHOLD FOR AN ADVISORY.
A MUCH QUIETER BUT COLD DAY ON TAP FOR MONDAY AS THE SURFACE RIDGE
CROSSES THE FORECAST AREA. THE SURFACE RIDGE GRADUALLY CROSSES THE
FORECAST AREA...WITH MOSTLY SUNNY SKIES TO START. SHOULD SEE SOME
INCREASE IN CLOUDS IN THE AFTERNOON AS THE SHORTWAVE COMING INTO
BRITISH COLUMBIA DROPS DOWN INTO THE SIOUX FALLS AREA BY 00Z. 925MB
TEMPS DONT START WARMING UNTIL LATE IN THE DAY...AND WITH FRESH
SNOW...HIGHS ONLY LOOK TO TOP OUT IN THE LOW TO MID TEENS. ITS
POSSIBLE SOME LOCATIONS IN NORTHEAST IOWA ONLY REACH THE SINGLE
DIGITS ABOVE ZERO AS SUGGESTED BY THE 01.12Z ECMWF/CANADIAN.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 220 PM CST SUN FEB 1 2015
LONG TERM CONCERNS...
1. BRIEF LIGHT SNOW MAKER MONDAY EVENING FOR MAINLY NORTHEAST IOWA
2. ANOTHER LIGHT SNOW MAKER FOR TUESDAY AFTERNOON/EVENING...MAINLY
SOUTH OF I-90
3. POSSIBLE WIND CHILL ADVISORY FOR THURSDAY MORNING
4. POSSIBILITY FOR A BRIEF WARM UP...BUT BREEZY...FOR FRIDAY INTO
SATURDAY.
SHORTWAVE OVER BRITISH COLUMBIA IS PROGGED TO DIG INTO SOUTHEAST
IOWA AND NORTHEAST MO BY 06Z TUESDAY. THIS TRACK HAS TRENDED
SOUTHWEST SLIGHTLY OVER THE PAST FEW DAYS. DESPITE ITS POTENT
NATURE/LOOK...MODELS DO NOT PRODUCE MUCH QPF WITH IT DUE TO
DRY AIR IN PLACE FROM MONDAY...WITH THE GFS ENTIRELY DRY. GIVEN ITS
STRENGTH FEEL THE NEED TO INCLUDE A LOW PRECIPITATION CHANCE FOR
MONDAY EVENING...SIMILAR TO THE PREVIOUS FORECAST. HOWEVER...WITH
THE SOUTHWEST TREND IN THE GUIDANCE...SHIFTED THE CHANCES A LITTLE
MORE SOUTHWEST AS WELL. SHOULD ANY SNOW OCCUR...MAYBE A FEW TENTHS
ACCUMULATE.
AFTER A QUIET OVERNIGHT MONDAY NIGHT INTO TUESDAY MORNING...POSSIBLY
A BIT COOL WITH A SURFACE RIDGE CROSSING...ANOTHER SHORTWAVE TROUGH
COMING TROUGH NORTHWEST FLOW IS PROGGED TO AFFECT THE AREA TUESDAY
AFTERNOON AND EVENING. THIS SHORTWAVE...ALTHOUGH WEAKER
COMPARED TO THE PREVIOUS ONE...HAS A LITTLE MORE MOISTURE TO WORK
WITH AND A STRONGER MID LEVEL FRONTOGENESIS ZONE. AS SUCH...01.12Z
NAM/GFS/ECMWF/CANADIAN ALL DEVELOP PRECIPITATION...WITH SOME EVEN
SHOWING POTENTIAL TO EXCEED 0.10 OF QPF IN 6 HOURS. SOME
TRACK ISSUES AGAIN EXIST...WITH THE STRONGEST CONSENSUS FOR THE SNOW
TO MOVE THROUGH LOCATIONS SOUTH OF I-90. UNLESS THE SHORTWAVE
BECOMES STRONGER IN LATER RUNS...FEEL THE PLACEMENT OF THIS SNOW
SHOULD STAY PERSISTENT. THUS...DID RAISE PRECIPITATION CHANCES
TOWARDS 50 ACROSS NORTHEAST IA/FAR SOUTHWEST WI. MAY END UP
ACCUMULATING 1-2 INCHES. SOME CONCERN TOO FOR THE PRECIPITATION TO
END AS FREEZING DRIZZLE AS ICE IS LOST ALOFT...BUT ITS VERY
POSSIBLE THE PRECIPITATION ENDS TOO ONCE WE LOSE THE ICE.
THEREFORE...HAVE YET TO INTRODUCE THIS INTO THE FORECAST.
SOMETHING TO MONITOR.
A STRONG UPPER TROUGH DROPS INTO THE REGION ON WEDNESDAY. THERE
COULD BE A LITTLE LIGHT SNOW IN OUR SOUTH DURING THE AFTERNOON WITH
ANOTHER FRONTOGENESIS BAND SETTING UP ACROSS IOWA AND ILLINOIS.
HOWEVER...THE MORE SIGNIFICANT PART IS THE ARCTIC AIR ACCOMPANY THE
UPPER TROUGH. 925MB TEMPS PLUMMET FROM -10 TO -13C AT 12Z WEDNESDAY
TO -18 TO -20C AT 12Z THURSDAY. A SOMEWHAT BRISK NORTHERLY BREEZE IS
PROGGED WEDNESDAY AFTERNOON AND EVENING BEFORE DIMINISHING
OVERNIGHT. THIS DIMINISHING COULD KEEP US JUST OUT OF A WIND CHILL
ADVISORY NEED FOR THURSDAY MORNING...BUT TEMPERATURES WOULD TANK
INSTEAD...ESPECIALLY IF SKIES ARE CLEAR. STAYED ON THE COOLER SIDE
OF GUIDANCE FOR LOWS WEDNESDAY NIGHT GIVEN THIS REGIME AND
THINKING ARCTIC AIR COMING IN WILL CLEAR SKIES OUT.
THE UPPER TROUGH IS FAST MOVING SUCH THAT WEAK UPPER RIDGING COMES
IN BY THURSDAY AFTERNOON...WITH NORTHWEST FLOW PERSISTING BEYOND
INTO SUNDAY. THUS...AFTER THE COLD START THURSDAY MORNING WE WILL BE
ON THE WARMING TREND HEADING INTO FRIDAY AND SATURDAY. STILL A LOT
OF SPREAD AMONGST ECMWF GUIDANCE REGARDING THE HIGHS FRIDAY AND
SATURDAY...BUT GENERAL TREND SHOULD BRING HIGHS BACK TO NORMAL.
GFS/ECMWF 925MB WINDS ALSO INCREASE TO 20-40KT ON FRIDAY...THUS
SUGGESTING IT COULD BE A BIT BREEZY. SOMETHING WELL HAVE TO WATCH
HEADING INTO NEXT WEEKEND IS A FRONTOGENETIC ZONE DROPPING SOUTHWEST
THROUGH THE FORECAST AREA. ACTUAL POSITION AND TIMING HAS VARIED
SOMEWHAT...REQUIRING LOW CHANCES OF PRECIPITATION THROUGH THE
WEEKEND. NEVERTHELESS...COULD SEE A COUPLE INCHES OF SNOW
ACCUMULATION. COOLER AIR FOLLOWS IN THE WAKE OF THIS ZONE FOR
SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1137 AM CST SUN FEB 1 2015
MESO MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE SNOW WILL END AT
BOTH TAF SITES BETWEEN 01.20Z AND 01.21Z. AT THE SAME TIME...THE
WIND GUSTS WILL BE DECREASING INTO THE 20 TO 30 KNOT RANGE. THE
WINDS WILL CONTINUE TO DECREASE RAPIDLY THIS EVENING AS THE
SURFACE PRESSURE GRADIENT RELAXES. MVRF CLOUDS WILL PERSIST INTO
THE EVENING...AND THEN QUICKLY DISSIPATE BETWEEN 02.03Z AND
02.06Z. SKIES WILL REMAIN MAINLY CLEAR THROUGH THE 02.18Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR WIZ054-061.
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
WIZ041>044-053-055.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
MNZ086>088-094>096.
IA...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR IAZ008>011-
018-019-029-030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1137 AM CST SUN FEB 1 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 323 AM CST SUN FEB 1 2015
CHALLENGES THIS MORNING INCLUDE SNOW AMOUNTS AND ASSOCIATED
HEADLINES. 01.00Z MODELS ARE IN GOOD OVERALL AGREEMENT AND WILL
USE A BLENDED SOLUTION.
CALLS TO LAW ENFORCEMENT EARLY THIS MORNING REVEALED 4 TO 5 INCHES
IN OSAGE AND 3 TO 4 INCHES IN DECORAH. FURTHER NORTH ALONG THE
I-90 CORRIDOR FROM ROCHESTER TO LA CROSSE...1 TO 2 INCHES IS
RELATIVELY COMMON. LATEST RAP SHOWS A MODEST BAND OF 850 HPA
FRONTOGENESIS RE-DEVELOPING ALONG THE MN/IA BORDER LATER THIS
MORNING. THIS LOWER LEVEL FORCING COMBINED WITH INCREASING
Q-VECTOR CONVERGENCE IN THE 500 TO 300 HPA LAYER ASSOCIATED WITH
THE APPROACHING CANADIAN TROUGH WILL RESULT IN 6-12 MORE HOURS OF
LIGHT SNOW ACROSS THE UPPER MS RIVER VALLEY.
LATEST REPORTS...MODEL/COBB DATA AND RADAR TRENDS PROVIDE ENOUGH
EVIDENCE TO JUSTIFY SOME CHANGES TO CURRENT HEADLINES. WILL EXTEND
THE WINTER STORM WARNING A TIER OF COUNTIES NORTHWARD FROM
MITCHELL TO CRAWFORD WHERE 6 TO 9 INCHES STORM TOTAL SNOW WILL
FALL. TO THE NORTH...WILL EXPAND THE WINTER WEATHER ADVISORY TO
INCLUDE THE I-90 CORRIDOR FROM OLMSTED TO JUNEAU/ADAMS COUNTIES
WHERE 3 TO 5 TOTAL INCHES ARE EXPECTED. FOR BOTH AREAS...THERE IS
LIKELY TO BE A SHARP GRADIENT IN SNOW AMOUNTS FROM NORTH TO SOUTH.
ALSO EXPECT AREAS OF BLOWING AND DRIFTING SNOW...ESPECIALLY ACROSS
WIND PRONE AREAS OF SOUTHEAST MN AND NORTHEAST IA GIVEN 30 TO 35
KTS AT THE TOP OF THE MIXED BOUNDARY LAYER. TRAVEL WILL REMAIN
DIFFICULT IF NOT HAZARDOUS FOR MUCH OF THE DAY.
ACCUMULATING SNOWFALL WILL QUICKLY TAPER OFF TO NOTHING NORTH OF
HIGHWAY 10 GIVEN VERY DRY AIRMASS ACROSS NORTHERN WI/MN WITH
SURFACE DEW POINTS DROPPING INTO THE TEENS TO LOWER 20S BELOW ZERO
ALONG THE CANADIAN BORDER. SNOW WILL SLOWLY DIMINISH AND MOVE OUT
OF THE REGION FROM NORTHWEST TO SOUTHEAST LATER THIS AFTERNOON.
TODAY WILL BE MARKEDLY COOLER WITH TEMPERATURES TOPPING OUT IN THE
TEENS...BUT WITH A STIFF NORTHERLY WIND...EXPECT WIND CHILL VALUES
IN THE SINGLE DIGITS BELOW ZERO. COLD CONDITIONS TO PERSIST
OVERNIGHT WITH CLEARING SKIES ALLOWING AIR TEMPERATURES TO DROP
BELOW ZERO. NORTHERLY WINDS FROM 5 TO 10 MPH WILL RESULT IN WIND
CHILLS FROM 10 TO 20 BELOW ZERO BY MONDAY MORNING.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 323 AM CST SUN FEB 1 2015
TEMPERATURES TO REMAIN AT OR BELOW EARLY FEBRUARY NORMALS THROUGH
THE UPCOMING WORK WEEK WITH DAILY HIGHS FROM THE MID TEENS TO MID
20S AND LOWS FROM THE SINGLE DIGITS BELOW AND ABOVE ZERO.
AFTER A DRY MONDAY...SNOW CHANCES RETURN MONDAY NIGHT THROUGH
MID-WEEK AND THEN AGAIN BY EARLY NEXT WEEKEND. CONFIDENCE IN
STRENGTH AND TIMING OF THE RESPONSIBLE SHORT-WAVES IN NORTHWEST
FLOW ALOFT ARE AVERAGE AT BEST. GIVEN OVERALL DRIER AIR PARCEL
SOURCE REGION...SNOW ACCUMULATIONS THROUGH THE WEEK APPEAR TO BE
RELATIVELY MINOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1137 AM CST SUN FEB 1 2015
MESO MODELS ARE IN FAIRLY GOOD AGREEMENT THAT THE SNOW WILL END AT
BOTH TAF SITES BETWEEN 01.20Z AND 01.21Z. AT THE SAME TIME...THE
WIND GUSTS WILL BE DECREASING INTO THE 20 TO 30 KNOT RANGE. THE
WINDS WILL CONTINUE TO DECREASE RAPIDLY THIS EVENING AS THE
SURFACE PRESSURE GRADIENT RELAXES. MVRF CLOUDS WILL PERSIST INTO
THE EVENING...AND THEN QUICKLY DISSIPATE BETWEEN 02.03Z AND
02.06Z. SKIES WILL REMAIN MAINLY CLEAR THROUGH THE 02.18Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR WIZ054-061.
WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
WIZ041>044-053-055.
MN...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
MNZ086>088-094>096.
IA...WINTER STORM WARNING UNTIL 9 PM CST THIS EVENING FOR IAZ008>011-
018-019-029-030.
&&
$$
SHORT TERM...ROGERS
LONG TERM...ROGERS
AVIATION...BOYNE