Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/13/16
AREA FORECAST DISCUSSION
NWS ALBANY NY
950 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL SWEEP ACROSS THE REGION
OVERNIGHT WITH SCATTERED SNOW SHOWERS AND ISOLATED SNOW SQUALLS
AHEAD OF IT. BEHIND THE ARCTIC COLD FRONT...THE COLDEST AIRMASS OF
THE SEASON WILL BUILD ACROSS THE REGION FOR THE WEEKEND WITH
BITTERLY COLD TEMPERATURES AND WIND CHILLS. A STORM SYSTEM MAY
IMPACT THE REGION MONDAY INTO THE MID WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 949 PM EST...AN ARCTIC COLD FRONT WILL BE MOVING THROUGH
THE REGION BTWN 04Z /11 PM/ AND 10Z /5 AM/ FROM NW TO SE. AHEAD OF
THIS FRONTAL BOUNDARY THERE WILL BE SCATTERED SNOW SHOWERS AND
PERHAPS A FEW EMBEDDED SNOW SQUALLS...ESPECIALLY NORTH AND WEST OF
THE CAPITAL REGION. THE LATEST 3-KM HRRR SHOWS THE CURRENT BAND OF
SNOW SHOWERS CURRENTLY WEST OF THE FCST ON THE LOCAL AND MOSAIC
RADAR IMAGERY MOVING INTO THE MOHAWK VALLEY...ADIRONDACKS...AND
CATSKILLS...AND THEN WEAKENING AS IT MOVES FURTHER DOWN STREAM
TOWARDS THE HUDSON RIVER VALLEY. SNOWFALL AMOUNTS ARE EXPECTED TO
BE ON THE LIGHT SIDE WITH GENERALLY A DUSTING TO 2 INCHES. THE
HIGHER TOTALS WILL BE OVER THE WRN DACKS. ANY SNOW SQUALLS WOULD
LIKELY REDUCE VISIBILITIES TO UNDER A QUARTER MILE BRIEFLY FOR A
SHORT PERIOD OF TIME. SOME CHANGES WERE MADE TO THE
POPS/CLOUDS/TEMPS BASED ON THE LATEST HRRR AND NAM12.
IT WILL BE ANOTHER VERY COLD NIGHT...BUT NOT AS COLD AS THE
TEMPERATURES LATER IN THE WEEKEND. LOWS OVERNIGHT WILL RANGE FROM
10 BELOW ZERO NORTHWEST AREAS TO 15 ABOVE ZERO SOUTHEAST TOWARDS
NW CT AND THE MID HUDSON RIVER VALLEY. WINDS WILL ALSO INCREASE
OVERNIGHT ACROSS THE FCST AREA WITH A WIND CHILL WARNING STARTING
AT 3 AM FOR THE SOUTHERN ADIRONDACKS...WESTERN MOHAWK
VALLEY...EASTERN CATSKILLS AND SOUTHERN VERMONT. THE JAIL BREAK OF
ARCTIC AIR KICKS IN...AS THE WINDS BEHIND THE FRONT WILL BE
MAINLY WEST TO SOUTHWEST AT 10 TO 20 MPH WITH GUSTS TO 30-40 MPH.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
WIND CHILL WARNINGS IN EFFECT FOR SATURDAY-SUNDAY MORNING FOR ALL
OF EASTERN NEW YORK AND ADJACENT WESTERN NEW ENGLAND.
THE COLDEST AIRMASS OF THE SEASON WILL BE WITH US OVER THE WEEKEND
IN THE WAKE OF THE ARCTIC FRONT AS AN ARCTIC AREA OF HIGH PRESSURE
SETTLES OVER THE REGION BY SUNDAY. H8 TEMPS DROP TO 27 TO 34
DEGREES BELOW ZERO BY SATURDAY EVENING. HAVE GONE WITH A NON-
DIURNAL RANGE OF TEMPS ON SATURDAY AS THE LOWS FRIDAY NIGHT AND
THE HIGHS ON SATURDAY SHOULD BE THE SAME WITH THE TEMPS DROPPING
ALL DAY ON SATURDAY. TEMPS ARE EXPECTED TO DROP FROM 10 BELOW TO
15 ABOVE ZERO EARLY SATURDAY MORNING TO 15 BELOW ZERO TO 5 ABOVE
ZERO BY EARLY SATURDAY EVENING. WIND CHILLS ON SATURDAY WILL RANGE
FROM 10 BELOW TO 35 BELOW ZERO WITH NORTHWEST WINDS 10 TO 20 MPH
WITH GUSTS 30 TO 40 MPH.
SATURDAY NIGHT WILL BE ESPECIALLY BRUTAL AS AIR TEMPERATURES ARE
EXPECTED TO DROP TO 5 BELOW TO NEAR 30 BELOW ZERO WITH WIND CHILL
VALUES 25 BELOW TO NEAR 50 BELOW ZERO.
SUNDAY INTO SUNDAY NIGHT...HIGH PRESSURE WILL MOVE OVER OUR REGION
ON SUNDAY AND OFF THE EASTERN SEABOARD LATE SUNDAY NIGHT. WINDS
WILL STILL BE FAIRLY STRONG ON SUNDAY MORNING BEFORE SUBSIDING
LATER SUNDAY INTO SUNDAY NIGHT. HIGHS ON SUNDAY WILL BE IN THE
ZERO TO 15 ABOVE ZERO RANGE WITH THE LOWS SUNDAY NIGHT BETWEEN 10
BELOW AND 5 ABOVE ZERO.
MONDAY WILL FEATURE INCREASING CLOUDS AS THE NEXT SYSTEM STARTS TO
TRACK NORTHEASTWARD FROM THE SOUTHEAST COAST. HIGHS WILL MODERATE
ON MONDAY RANGING FROM THE UPPER TEENS NORTHWEST TO UPPER 20S
SOUTHEAST WITH A CHANCE OF SNOW ACROSS THE SOUTHERN HALF OF THE FA
LATE IN THE DAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A SIGNIFICANT STORM IS EXPECTED TO IMPACT THE REGION DURING THE
EARLY PART OF THE EXTENDED PERIOD. THERE IS INCREASING CONFIDENCE
AS TO THE TRACK AND INTENSITY OF THIS SYSTEM... AT LEAST IN ITS
EARLY STAGES. TWO TO SIX INCH ACCUMULATIONS ARE EXPECTED MONDAY
NIGHT... WHICH IS MORE OR LESS THE START OF THE EVENT. BEYOND THAT
THERE IS STILL UNCERTAINTY AS TO PRECIPITATION TYPE AS THERE IS
PLENTY OF MILD AIR TO BE DRAWN IN OUT AHEAD OF THIS SYSTEM...THUS
THE EXACT TRACK AND INTENSITY WILL BE CRUCIAL. RIGHT NOW...THE
TRACK IS EXPECTED TO BE FROM ABOUT CHARLOTTE NORTH CAROLINA
THROUGH ALBANY.
BECAUSE THE TRACK IS NOT SEEN AS GOING FAR ENOUGH TO THE EAST TO
GIVE US AN ALL SNOW EVENT...INDICATIONS ARE PRECIPITATION WILL
LIKELY CHANGE OVER TO RAIN FOR A TIME ON TUESDAY...PARTICULARLY
OUTSIDE OF THE ADIRONDACKS...BEFORE EVERYTHING TAPERS OFF AS SNOW
TUESDAY NIGHT. THERE IS THE POTENTIAL FOR VERY SIGNIFICANT
ACCUMULATIONS...BUT ANY DECENT PERIOD OF RAIN...AS IS EXPECTED RIGHT
NOW...WILL KEEP SNOW ACCUMULATIONS AT BAY.
BROAD LAKE ENHANCEMENT ON INCREASING WESTERLY WINDS BEHIND THE
DEPARTING STORM WILL KEEP SNOW SHOWERS OF LIGHT AMOUNTS GOING FOR
MANY AREAS TUESDAY NIGHT...WITH MIXED RAIN AND SNOW SHOWERS FOR
WEDNESDAY. BUT THE ACTIVITY WILL WIND DOWN RAPIDLY ON THURSDAY AS
HIGH PRESSURE SETTLES IN...BUT WITHOUT THE EXTREME COLD WE/RE
EXPECTING THIS WEEKEND.
HIGH TEMPERATURES ARE EXPECTED TO RANGE FROM THE MID 30S THROUGH THE
UPPER 40S ON TUESDAY...THE UPPER 20S TO AROUND 40 DEGREES ON
WEDNESDAY...AND THE MID TEENS TO AROUND 30 DEGREES ON THURSDAY.
FRIDAY HIGHS WILL REBOUND SOMEWHAT. OVERNIGHT LOWS MONDAY NIGHT
WILL RANGE FROM THE UPPER TEENS IN THE MOUNTAINS TO THE UPPER 20S IN
THE LOWER MID HUDSON VALLEY. TUESDAY NIGHT...THEY WILL RANGE FROM
THE MID 20S IN THE WESTERN ADIRONDACKS...TO THE LOWER 30S DOWN THE
HUDSON VALLEY. WEDNESDAY NIGHT WILL TURN SHARPLY COLDER...AND
THURSDAY NIGHT WILL BE COLDEST...WITH LOWS RANGING FROM THE LOW
SINGLE DIGITS IN THE WESTERN ADIRONDACKS...TO THE UPPER TEENS DOWN
THE MID HUDSON VALLEY.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
A CLIPPER LOW WILL PASS NORTH OF THE REGION TONIGHT...AS THE
ARCTIC COLD FRONT WILL MOVE THROUGH OVERNIGHT. A NW FLOW OF ARCTIC
AIR WILL IMPACT THE REGION THROUGH THE DAY INTO THE NIGHT PERIOD
WITH GUSTY WINDS.
THE ARCTIC FRONT WILL FOCUS SOME ISOLATED TO SCATTERED SNOW
SHOWERS OR A SQUALL FROM THE CAPITAL REGION NORTH...IMPACTING
KGFL/KALB/KPSF BTWN 04Z-09Z. THE SNOW SHOWERS WILL BE FAIRLY
ISOLATED TO SCATTERED IN COVERAGE DUE TO VERY LIMITED LOW-LEVEL
MOISTURE. A VCSH WAS USED AT KALB/KPSF AFTER 05Z...AND A TEMPO
WAS USED FOR MVFR CONDITIONS AT KGFL BTWN 04Z-06Z.
VFR CONDITIONS WILL BE DOMINATE...ASIDE FOR SOME MVFR CIGS/VSBYS
WITH ANY SNOW SHOWERS/ISOLD SQUALLS ESPECIALLY AT KPSF/KGFL. CIGS
WILL BE MAINLY IN THE 4-9 KFT AGL RANGE. IN THE WAKE OF THE FRONT
LATE TOMORROW MORNING...SOME LINGERING STRATOCUMULUS OR MID LEVEL
CLOUDS WILL LINGER. OVERALL...VFR CONDITIONS WILL CONTINUE IN THE
FRIGID NORTHWEST FLOW THROUGH THE PM.
THE WINDS WILL BE FROM THE SOUTH TO SOUTHWEST AT 4-10 KTS PRIOR TO
MIDNIGHT...THEN VEER TO THE W TO NW AT 6-12 KTS BEFORE DAYBREAK
WITH SOME GUSTS TO 20-25 KTS. THE WINDS WILL INCREASE IN THE WAKE
OF THE ARCTIC FRONT LATE TOMORROW MORNING INTO THE AFTERNOON AT
12-20 KTS WITH SOME GUSTS AROUND 30 KTS...ESPECIALLY AT KALB/KPSF.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
SUNDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE SN.
WASHINGTONS BIRTHDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...SN.
MONDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA...SN.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
WITH BITTER COLD AIR IN PLACE...ICE COVERAGE ON RIVERS AND LAKES
WILL CONTINUE TO INCREASE AND STRENGTHEN OVER THE NEXT FEW DAYS. A
FEW LIGHT SNOW SHOWERS ARE POSSIBLE...MAINLY THIS EVENING...BUT THIS
WILL AMOUNT TO LITTLE IF ANY HYDROLOGIC SIGNIFICANCE.
HOWEVER...THERE IS THE POTENTIAL FOR A HEAVY PRECIPITATION EVENT TO
IMPACT THE REGION FROM MONDAY NIGHT THROUGH WEDNESDAY. THERE
REMAINS CONSIDERABLE UNCERTAINTY REGARDING THE TYPES OF
PRECIPITATION THAT MAY OCCUR...WHICH WILL ULTIMATELY DEPEND ON THE
EXACT TRACK OF THIS POTENTIAL STORM SYSTEM. AT THIS TIME...MODEL
GUIDANCE IS SUGGESTING ONE TO THREE INCHES OF LIQUID EQUIVALENT
COULD OCCUR...AND MUCH OF THIS COULD BE IN THE FORM OF RAIN. IF
THIS RAIN WERE TO MATERIALIZE...IT COULD HAVE A HIGH IMPACT ON
RIVERS AND STREAMS...ESP CONSIDERING THE GROUND WILL BE FULLY
FROZEN BY THAT TIME...ALLOWING MUCH OF THE PRECIP TO BE RUNOFF.
DETAILS WILL BECOME MORE CERTAIN OVER THE NEXT FEW DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WIND CHILL WARNING FROM 1 PM SATURDAY TO 1 PM EST SUNDAY FOR
CTZ001-013.
NY...WIND CHILL WARNING FROM 3 AM SATURDAY TO 1 PM EST SUNDAY FOR
NYZ032-033-038-042-047-051-058-063-082.
WIND CHILL WARNING FROM 1 PM SATURDAY TO 1 PM EST SUNDAY FOR
NYZ039>041-043-048>050-052>054-059>061-064>066-083-084.
MA...WIND CHILL WARNING FROM 1 PM SATURDAY TO 1 PM EST SUNDAY FOR
MAZ001-025.
VT...WIND CHILL WARNING FROM 3 AM SATURDAY TO 1 PM EST SUNDAY FOR
VTZ013>015.
&&
$$
SYNOPSIS...IRL/WASULA
NEAR TERM...11/WASULA
SHORT TERM...11
LONG TERM...ELH
AVIATION...WASULA
HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS ALBANY NY
714 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL SWEEP ACROSS THE REGION TONIGHT WITH
SCATTERED SNOW SHOWERS AND ISOLATED SNOW SQUALLS AHEAD OF IT.
BEHIND THE ARCTIC COLD FRONT...THE COLDEST AIRMASS OF THE SEASON
WILL BUILD ACROSS THE REGION FOR THE WEEKEND WITH BITTERLY COLD
TEMPERATURES AND WIND CHILLS.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 635 PM EST...AN ARCTIC COLD FRONT WILL BE MOVING THROUGH
THE REGION LATER THIS EVENING THROUGH THE OVERNIGHT HOURS. AHEAD
OF THIS FRONTAL BOUNDARY THERE WILL BE SCATTERED SNOW SHOWERS AND
PERHAPS A FEW EMBEDDED SNOW SQUALLS. SNOWFALL AMOUNTS ARE EXPECTED
TO BE ON THE LIGHT SIDE WITH GENERALLY A DUSTING TO 2 INCHES. ANY
SNOW SQUALLS WOULD LIKELY REDUCE VISIBILITY SIGNIFICANTLY FOR A
SHORT PERIOD OF TIME. THE CLOUDS ARE TAKING THERE TIME FILLING IN
NORTH AND EAST OF THE CAPITAL REGION...SO SOME MINOR CHANGES WERE
MADE TO SKYCOVER PRIOR TO 10 PM...THE INITIAL SURGE OF SNOW
SHOWERS/EMBEDDED SQUALLS IS MOVING EAST OF LAKES ONTARIO...AND
ERIE...AND WILL REACH THE WRN DACKS BETWEEN 8-10 PM EST WITH THE
LIGHT ACCUMS. THE LATEST 3-KM HRRR CONTINUES TO SHOW THIS BAND
WEAKENING AS IT MOVES EAST OF THE DACKS AROUND MIDNIGHT. SOME
MINOR CHANGES WERE ALSO MADE TO THE POP TRENDS.
IT WILL BE ANOTHER COLD NIGHT...BUT NOT AS COLD AS THE
TEMPERATURES LATER IN THE WEEKEND. LOWS OVERNIGHT WILL RANGE FROM
10 BELOW ZERO NORTHWEST TO 15 ABOVE ZERO SOUTHEAST. WINDS WILL
ALSO INCREASE OVERNIGHT ACROSS THE FA WITH A WIND CHILL WARNING
STARTING AT 3 AM FOR THE SOUTHERN ADIRONDACKS...WESTERN MOHAWK
VALLEY...EASTERN CATSKILLS AND SOUTHERN VERMONT. WINDS BEHIND THE
FRONT WILL BE MAINLY WEST TO SOUTHWEST AT 10 TO 20 MPH WITH GUSTS
TO 30 MPH.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
WIND CHILL WARNINGS IN EFFECT FOR SATURDAY-SUNDAY MORNING FOR ALL
OF EASTERN NEW YORK AND ADJACENT WESTERN NEW ENGLAND.
THE COLDEST AIRMASS OF THE SEASON WILL BE WITH US OVER THE WEEKEND
IN THE WAKE OF THE ARCTIC FRONT AS AN ARCTIC AREA OF HIGH PRESSURE
SETTLES OVER THE REGION BY SUNDAY. H8 TEMPS DROP TO 27 TO 34
DEGREES BELOW ZERO BY SATURDAY EVENING. HAVE GONE WITH A NON-
DIURNAL RANGE OF TEMPS ON SATURDAY AS THE LOWS FRIDAY NIGHT AND
THE HIGHS ON SATURDAY SHOULD BE THE SAME WITH THE TEMPS DROPPING
ALL DAY ON SATURDAY. TEMPS ARE EXPECTED TO DROP FROM 10 BELOW TO
15 ABOVE ZERO EARLY SATURDAY MORNING TO 15 BELOW ZERO TO 5 ABOVE
ZERO BY EARLY SATURDAY EVENING. WIND CHILLS ON SATURDAY WILL RANGE
FROM 10 BELOW TO 35 BELOW ZERO WITH NORTHWEST WINDS 10 TO 20 MPH
WITH GUSTS 30 TO 40 MPH.
SATURDAY NIGHT WILL BE ESPECIALLY BRUTAL AS AIR TEMPERATURES ARE
EXPECTED TO DROP TO 5 BELOW TO NEAR 30 BELOW ZERO WITH WIND CHILL
VALUES 25 BELOW TO NEAR 50 BELOW ZERO.
SUNDAY INTO SUNDAY NIGHT...HIGH PRESSURE WILL MOVE OVER OUR REGION
ON SUNDAY AND OFF THE EASTERN SEABOARD LATE SUNDAY NIGHT. WINDS
WILL STILL BE FAIRLY STRONG ON SUNDAY MORNING BEFORE SUBSIDING
LATER SUNDAY INTO SUNDAY NIGHT. HIGHS ON SUNDAY WILL BE IN THE
ZERO TO 15 ABOVE ZERO RANGE WITH THE LOWS SUNDAY NIGHT BETWEEN 10
BELOW AND 5 ABOVE ZERO.
MONDAY WILL FEATURE INCREASING CLOUDS AS THE NEXT SYSTEM STARTS TO
TRACK NORTHEASTWARD FROM THE SOUTHEAST COAST. HIGHS WILL MODERATE
ON MONDAY RANGING FROM THE UPPER TEENS NORTHWEST TO UPPER 20S
SOUTHEAST WITH A CHANCE OF SNOW ACROSS THE SOUTHERN HALF OF THE FA
LATE IN THE DAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A SIGNIFICANT STORM IS EXPECTED TO IMPACT THE REGION DURING THE
EARLY PART OF THE EXTENDED PERIOD. THERE IS INCREASING CONFIDENCE
AS TO THE TRACK AND INTENSITY OF THIS SYSTEM... AT LEAST IN ITS
EARLY STAGES. TWO TO SIX INCH ACCUMULATIONS ARE EXPECTED MONDAY
NIGHT... WHICH IS MORE OR LESS THE START OF THE EVENT. BEYOND THAT
THERE IS STILL UNCERTAINTY AS TO PRECIPITATION TYPE AS THERE IS
PLENTY OF MILD AIR TO BE DRAWN IN OUT AHEAD OF THIS SYSTEM...THUS
THE EXACT TRACK AND INTENSITY WILL BE CRUCIAL. RIGHT NOW...THE
TRACK IS EXPECTED TO BE FROM ABOUT CHARLOTTE NORTH CAROLINA
THROUGH ALBANY.
BECAUSE THE TRACK IS NOT SEEN AS GOING FAR ENOUGH TO THE EAST TO
GIVE US AN ALL SNOW EVENT...INDICATIONS ARE PRECIPITATION WILL
LIKELY CHANGE OVER TO RAIN FOR A TIME ON TUESDAY...PARTICULARLY
OUTSIDE OF THE ADIRONDACKS...BEFORE EVERYTHING TAPERS OFF AS SNOW
TUESDAY NIGHT. THERE IS THE POTENTIAL FOR VERY SIGNIFICANT
ACCUMULATIONS...BUT ANY DECENT PERIOD OF RAIN...AS IS EXPECTED RIGHT
NOW...WILL KEEP SNOW ACCUMULATIONS AT BAY.
BROAD LAKE ENHANCEMENT ON INCREASING WESTERLY WINDS BEHIND THE
DEPARTING STORM WILL KEEP SNOW SHOWERS OF LIGHT AMOUNTS GOING FOR
MANY AREAS TUESDAY NIGHT...WITH MIXED RAIN AND SNOW SHOWERS FOR
WEDNESDAY. BUT THE ACTIVITY WILL WIND DOWN RAPIDLY ON THURSDAY AS
HIGH PRESSURE SETTLES IN...BUT WITHOUT THE EXTREME COLD WE/RE
EXPECTING THIS WEEKEND.
HIGH TEMPERATURES ARE EXPECTED TO RANGE FROM THE MID 30S THROUGH THE
UPPER 40S ON TUESDAY...THE UPPER 20S TO AROUND 40 DEGREES ON
WEDNESDAY...AND THE MID TEENS TO AROUND 30 DEGREES ON THURSDAY.
FRIDAY HIGHS WILL REBOUND SOMEWHAT. OVERNIGHT LOWS MONDAY NIGHT
WILL RANGE FROM THE UPPER TEENS IN THE MOUNTAINS TO THE UPPER 20S IN
THE LOWER MID HUDSON VALLEY. TUESDAY NIGHT...THEY WILL RANGE FROM
THE MID 20S IN THE WESTERN ADIRONDACKS...TO THE LOWER 30S DOWN THE
HUDSON VALLEY. WEDNESDAY NIGHT WILL TURN SHARPLY COLDER...AND
THURSDAY NIGHT WILL BE COLDEST...WITH LOWS RANGING FROM THE LOW
SINGLE DIGITS IN THE WESTERN ADIRONDACKS...TO THE UPPER TEENS DOWN
THE MID HUDSON VALLEY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
A CLIPPER LOW WILL PASS NORTH OF THE REGION TONIGHT...AS THE
ARCTIC COLD FRONT WILL MOVE THROUGH OVERNIGHT. A NW FLOW OF ARCTIC
AIR WILL IMPACT THE REGION THROUGH THE DAY INTO THE NIGHT PERIOD
WITH GUSTY WINDS.
THE ARCTIC FRONT WILL FOCUS SOME ISOLATED TO SCATTERED SNOW
SHOWERS OR A SQUALL FROM THE CAPITAL REGION NORTH...IMPACTING
KGFL/KALB/KPSF BTWN 04Z-09Z. THE SNOW SHOWERS WILL BE FAIRLY
ISOLATED TO SCATTERED IN COVERAGE DUE TO VERY LIMITED LOW-LEVEL
MOISTURE. A VCSH WAS USED AT KALB/KPSF AFTER 05Z...AND A TEMPO
WAS USED FOR MVFR CONDITIONS AT KGFL BTWN 04Z-06Z.
VFR CONDITIONS WILL BE DOMINATE...ASIDE FOR SOME MVFR CIGS/VSBYS
WITH ANY SNOW SHOWERS/ISOLD SQUALLS ESPECIALLY AT KPSF/KGFL. CIGS
WILL BE MAINLY IN THE 4-9 KFT AGL RANGE. IN THE WAKE OF THE FRONT
LATE TOMORROW MORNING...SOME LINGERING STRATOCUMULUS OR MID LEVEL
CLOUDS WILL LINGER. OVERALL...VFR CONDITIONS WILL CONTINUE IN THE
FRIGID NORTHWEST FLOW THROUGH THE PM.
THE WINDS WILL BE FROM THE SOUTH TO SOUTHWEST AT 4-10 KTS PRIOR TO
MIDNIGHT...THEN VEER TO THE W TO NW AT 6-12 KTS BEFORE DAYBREAK
WITH SOME GUSTS TO 20-25 KTS. THE WINDS WILL INCREASE IN THE WAKE
OF THE ARCTIC FRONT LATE TOMORROW MORNING INTO THE AFTERNOON AT
12-20 KTS WITH SOME GUSTS AROUND 30 KTS...ESPECIALLY AT KALB/KPSF.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
SUNDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE SN.
WASHINGTONS BIRTHDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...SN.
MONDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA...SN.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
WITH BITTER COLD AIR IN PLACE...ICE COVERAGE ON RIVERS AND LAKES
WILL CONTINUE TO INCREASE AND STRENGTHEN OVER THE NEXT FEW DAYS. A
FEW LIGHT SNOW SHOWERS ARE POSSIBLE...MAINLY THIS EVENING...BUT THIS
WILL AMOUNT TO LITTLE IF ANY HYDROLOGIC SIGNIFICANCE.
HOWEVER...THERE IS THE POTENTIAL FOR A HEAVY PRECIPITATION EVENT TO
IMPACT THE REGION FROM MONDAY NIGHT THROUGH WEDNESDAY. THERE
REMAINS CONSIDERABLE UNCERTAINTY REGARDING THE TYPES OF
PRECIPITATION THAT MAY OCCUR...WHICH WILL ULTIMATELY DEPEND ON THE
EXACT TRACK OF THIS POTENTIAL STORM SYSTEM. AT THIS TIME...MODEL
GUIDANCE IS SUGGESTING ONE TO THREE INCHES OF LIQUID EQUIVALENT
COULD OCCUR...AND MUCH OF THIS COULD BE IN THE FORM OF RAIN. IF
THIS RAIN WERE TO MATERIALIZE...IT COULD HAVE A HIGH IMPACT ON
RIVERS AND STREAMS...ESP CONSIDERING THE GROUND WILL BE FULLY
FROZEN BY THAT TIME...ALLOWING MUCH OF THE PRECIP TO BE RUNOFF.
DETAILS WILL BECOME MORE CERTAIN OVER THE NEXT FEW DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WIND CHILL WARNING FROM 1 PM SATURDAY TO 1 PM EST SUNDAY FOR
CTZ001-013.
NY...WIND CHILL WARNING FROM 3 AM SATURDAY TO 1 PM EST SUNDAY FOR
NYZ032-033-038-042-047-051-058-063-082.
WIND CHILL WARNING FROM 1 PM SATURDAY TO 1 PM EST SUNDAY FOR
NYZ039>041-043-048>050-052>054-059>061-064>066-083-084.
MA...WIND CHILL WARNING FROM 1 PM SATURDAY TO 1 PM EST SUNDAY FOR
MAZ001-025.
VT...WIND CHILL WARNING FROM 3 AM SATURDAY TO 1 PM EST SUNDAY FOR
VTZ013>015.
&&
$$
SYNOPSIS...IRL/WASULA
NEAR TERM...11/WASULA
SHORT TERM...11
LONG TERM...ELH
AVIATION...WASULA
HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS ALBANY NY
635 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL SWEEP ACROSS THE REGION TONIGHT WITH
SCATTERED SNOW SHOWERS AND ISOLATED SNOW SQUALLS AHEAD OF IT.
BEHIND THE ARCTIC COLD FRONT...THE COLDEST AIRMASS OF THE SEASON
WILL BUILD ACROSS THE REGION FOR THE WEEKEND WITH BITTERLY COLD
TEMPERATURES AND WIND CHILLS.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 634 PM EST...AN ARCTIC COLD FRONT WILL BE MOVING THROUGH
THE REGION LATER THIS EVENING THROUGH THE OVERNIGHT HOURS. AHEAD
OF THIS FRONTAL BOUNDARY THERE WILL BE SCATTERED SNOW SHOWERS AND
PERHAPS A FEW EMBEDDED SNOW SQUALLS. SNOWFALL AMOUNTS ARE EXPECTED
TO BE ON THE LIGHT SIDE WITH GENERALLY A DUSTING TO 2 INCHES. ANY
SNOW SQUALLS WOULD LIKELY REDUCE VISIBILITY SIGNIFICANTLY FOR A
SHORT PERIOD OF TIME. THE CLOUDS ARE TAKING THERE TIME FILLING IN
NORTH AND EAST OF THE CAPITAL REGION...SO SOME MINOR CHANGES WERE
MADE TO SKYCOVER PRIOR TO 10 PM...THE INITIAL SURGE OF SNOW
SHOWERS/EMBEDDED SQUALLS IS MOVING EAST OF LAKES ONTARIO...AND
ERIE...AND WILL REACH THE WRN DACKS BETWEEN 8-10 PM EST WITH THE
LIGHT ACCUMS. THE LATEST 3-KM HRRR CONTINUES TO SHOW THIS BAND
WEAKENING AS IT MOVES EAST OF THE DACKS AROUND MIDNIGHT. SOME
MINOR CHANGES WERE ALSO MADE TO THE POP TRENDS.
IT WILL BE ANOTHER COLD NIGHT...BUT NOT AS COLD AS THE
TEMPERATURES LATER IN THE WEEKEND. LOWS OVERNIGHT WILL RANGE FROM
10 BELOW ZERO NORTHWEST TO 15 ABOVE ZERO SOUTHEAST. WINDS WILL
ALSO INCREASE OVERNIGHT ACROSS THE FA WITH A WIND CHILL WARNING
STARTING AT 3 AM FOR THE SOUTHERN ADIRONDACKS...WESTERN MOHAWK
VALLEY...EASTERN CATSKILLS AND SOUTHERN VERMONT. WINDS BEHIND THE
FRONT WILL BE MAINLY WEST TO SOUTHWEST AT 10 TO 20 MPH WITH GUSTS
TO 30 MPH.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
WIND CHILL WARNINGS IN EFFECT FOR SATURDAY-SUNDAY MORNING FOR ALL
OF EASTERN NEW YORK AND ADJACENT WESTERN NEW ENGLAND.
THE COLDEST AIRMASS OF THE SEASON WILL BE WITH US OVER THE WEEKEND
IN THE WAKE OF THE ARCTIC FRONT AS AN ARCTIC AREA OF HIGH PRESSURE
SETTLES OVER THE REGION BY SUNDAY. H8 TEMPS DROP TO 27 TO 34
DEGREES BELOW ZERO BY SATURDAY EVENING. HAVE GONE WITH A NON-
DIURNAL RANGE OF TEMPS ON SATURDAY AS THE LOWS FRIDAY NIGHT AND
THE HIGHS ON SATURDAY SHOULD BE THE SAME WITH THE TEMPS DROPPING
ALL DAY ON SATURDAY. TEMPS ARE EXPECTED TO DROP FROM 10 BELOW TO
15 ABOVE ZERO EARLY SATURDAY MORNING TO 15 BELOW ZERO TO 5 ABOVE
ZERO BY EARLY SATURDAY EVENING. WIND CHILLS ON SATURDAY WILL RANGE
FROM 10 BELOW TO 35 BELOW ZERO WITH NORTHWEST WINDS 10 TO 20 MPH
WITH GUSTS 30 TO 40 MPH.
SATURDAY NIGHT WILL BE ESPECIALLY BRUTAL AS AIR TEMPERATURES ARE
EXPECTED TO DROP TO 5 BELOW TO NEAR 30 BELOW ZERO WITH WIND CHILL
VALUES 25 BELOW TO NEAR 50 BELOW ZERO.
SUNDAY INTO SUNDAY NIGHT...HIGH PRESSURE WILL MOVE OVER OUR REGION
ON SUNDAY AND OFF THE EASTERN SEABOARD LATE SUNDAY NIGHT. WINDS
WILL STILL BE FAIRLY STRONG ON SUNDAY MORNING BEFORE SUBSIDING
LATER SUNDAY INTO SUNDAY NIGHT. HIGHS ON SUNDAY WILL BE IN THE
ZERO TO 15 ABOVE ZERO RANGE WITH THE LOWS SUNDAY NIGHT BETWEEN 10
BELOW AND 5 ABOVE ZERO.
MONDAY WILL FEATURE INCREASING CLOUDS AS THE NEXT SYSTEM STARTS TO
TRACK NORTHEASTWARD FROM THE SOUTHEAST COAST. HIGHS WILL MODERATE
ON MONDAY RANGING FROM THE UPPER TEENS NORTHWEST TO UPPER 20S
SOUTHEAST WITH A CHANCE OF SNOW ACROSS THE SOUTHERN HALF OF THE FA
LATE IN THE DAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A SIGNIFICANT STORM IS EXPECTED TO IMPACT THE REGION DURING THE
EARLY PART OF THE EXTENDED PERIOD. THERE IS INCREASING CONFIDENCE
AS TO THE TRACK AND INTENSITY OF THIS SYSTEM... AT LEAST IN ITS
EARLY STAGES. TWO TO SIX INCH ACCUMULATIONS ARE EXPECTED MONDAY
NIGHT... WHICH IS MORE OR LESS THE START OF THE EVENT. BEYOND THAT
THERE IS STILL UNCERTAINTY AS TO PRECIPITATION TYPE AS THERE IS
PLENTY OF MILD AIR TO BE DRAWN IN OUT AHEAD OF THIS SYSTEM...THUS
THE EXACT TRACK AND INTENSITY WILL BE CRUCIAL. RIGHT NOW...THE
TRACK IS EXPECTED TO BE FROM ABOUT CHARLOTTE NORTH CAROLINA
THROUGH ALBANY.
BECAUSE THE TRACK IS NOT SEEN AS GOING FAR ENOUGH TO THE EAST TO
GIVE US AN ALL SNOW EVENT...INDICATIONS ARE PRECIPITATION WILL
LIKELY CHANGE OVER TO RAIN FOR A TIME ON TUESDAY...PARTICULARLY
OUTSIDE OF THE ADIRONDACKS...BEFORE EVERYTHING TAPERS OFF AS SNOW
TUESDAY NIGHT. THERE IS THE POTENTIAL FOR VERY SIGNIFICANT
ACCUMULATIONS...BUT ANY DECENT PERIOD OF RAIN...AS IS EXPECTED RIGHT
NOW...WILL KEEP SNOW ACCUMULATIONS AT BAY.
BROAD LAKE ENHANCEMENT ON INCREASING WESTERLY WINDS BEHIND THE
DEPARTING STORM WILL KEEP SNOW SHOWERS OF LIGHT AMOUNTS GOING FOR
MANY AREAS TUESDAY NIGHT...WITH MIXED RAIN AND SNOW SHOWERS FOR
WEDNESDAY. BUT THE ACTIVITY WILL WIND DOWN RAPIDLY ON THURSDAY AS
HIGH PRESSURE SETTLES IN...BUT WITHOUT THE EXTREME COLD WE/RE
EXPECTING THIS WEEKEND.
HIGH TEMPERATURES ARE EXPECTED TO RANGE FROM THE MID 30S THROUGH THE
UPPER 40S ON TUESDAY...THE UPPER 20S TO AROUND 40 DEGREES ON
WEDNESDAY...AND THE MID TEENS TO AROUND 30 DEGREES ON THURSDAY.
FRIDAY HIGHS WILL REBOUND SOMEWHAT. OVERNIGHT LOWS MONDAY NIGHT
WILL RANGE FROM THE UPPER TEENS IN THE MOUNTAINS TO THE UPPER 20S IN
THE LOWER MID HUDSON VALLEY. TUESDAY NIGHT...THEY WILL RANGE FROM
THE MID 20S IN THE WESTERN ADIRONDACKS...TO THE LOWER 30S DOWN THE
HUDSON VALLEY. WEDNESDAY NIGHT WILL TURN SHARPLY COLDER...AND
THURSDAY NIGHT WILL BE COLDEST...WITH LOWS RANGING FROM THE LOW
SINGLE DIGITS IN THE WESTERN ADIRONDACKS...TO THE UPPER TEENS DOWN
THE MID HUDSON VALLEY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
VFR FLYING CONDITIONS ARE EXPECTED TO PREVAIL THROUGHOUT THE TAF
PERIOD AS AN ARCTIC COLD FRONT AND SOME SCATTERED SNOW SHOWERS
MOVE ACROSS THE REGION TONIGHT.
THIS AFTERNOON...WINDS WILL BE S-SW AT AROUND 5-10 KTS. SKIES WILL
FEATURE BKN/OVC PASSING CIRRUS WITH SOME FEW-SCT DIURNAL CU
DEVELOPING LATE THIS AFTERNOON. CLOUDS WILL EVENTUALLY INCREASE
THIS EVENING AS AN ARCTIC FRONTAL BOUNDARY STARTS TO APPROACH FROM
THE EASTERN GREAT LAKES.
TONIGHT INTO SATURDAY...THIS FRONTAL BOUNDARY MAY ALLOW FOR A
ROGUE SNOW SHOWER OR SNOW SQUALL FOR LATE TONIGHT...MAINLY AFTER
MIDNIGHT AT KALB AND KPSF...BUT AS EARLY AS 03Z AT KGFL. SNOW
SHOWERS WILL BE FAIRLY SCATTERED IN COVERAGE DUE TO LIMITED
MOISTURE IN PLACE...SO WILL ONLY ADDRESS WITH VCSH. DID NOT
INCLUDE MENTION OF VCSH AT KPOU AS ANY SNOW SHOWER ACTIVITY IS
EXPECTED TO STAY PRIMARILY NORTH. OTHERWISE...IT SHOULD CONTINUE
TO BE VFR TONIGHT WITH BKN-OVC CIGS AROUND 4-8 KFT...AND SW WINDS
AROUND 5 KTS. WINDS WILL EVENTUALLY SWITCH TO THE WEST BEHIND THE
FRONTAL BOUNDARY TOWARDS 12Z SATURDAY AND INCREASE TO 10-15 KTS.
WINDS WILL BE GUSTY AT TIMES BY THE END OF THE TAF PERIOD...IN THE
20-25 KNOT RANGE ESPECIALLY AT KALB.
OUTLOOK...
SATURDAY THROUGH SATURDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO
SIG WX.
SUNDAY THROUGH SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
WASHINGTONS BIRTHDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SN.
MONDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SN...SLEET.
TUESDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...FZRA.
&&
.HYDROLOGY...
WITH BITTER COLD AIR IN PLACE...ICE COVERAGE ON RIVERS AND LAKES
WILL CONTINUE TO INCREASE AND STRENGTHEN OVER THE NEXT FEW DAYS. A
FEW LIGHT SNOW SHOWERS ARE POSSIBLE...MAINLY THIS EVENING...BUT THIS
WILL AMOUNT TO LITTLE IF ANY HYDROLOGIC SIGNIFICANCE.
HOWEVER...THERE IS THE POTENTIAL FOR A HEAVY PRECIPITATION EVENT TO
IMPACT THE REGION FROM MONDAY NIGHT THROUGH WEDNESDAY. THERE
REMAINS CONSIDERABLE UNCERTAINTY REGARDING THE TYPES OF
PRECIPITATION THAT MAY OCCUR...WHICH WILL ULTIMATELY DEPEND ON THE
EXACT TRACK OF THIS POTENTIAL STORM SYSTEM. AT THIS TIME...MODEL
GUIDANCE IS SUGGESTING ONE TO THREE INCHES OF LIQUID EQUIVALENT
COULD OCCUR...AND MUCH OF THIS COULD BE IN THE FORM OF RAIN. IF
THIS RAIN WERE TO MATERIALIZE...IT COULD HAVE A HIGH IMPACT ON
RIVERS AND STREAMS...ESP CONSIDERING THE GROUND WILL BE FULLY
FROZEN BY THAT TIME...ALLOWING MUCH OF THE PRECIP TO BE RUNOFF.
DETAILS WILL BECOME MORE CERTAIN OVER THE NEXT FEW DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WIND CHILL WARNING FROM 1 PM SATURDAY TO 1 PM EST SUNDAY FOR
CTZ001-013.
NY...WIND CHILL WARNING FROM 3 AM SATURDAY TO 1 PM EST SUNDAY FOR
NYZ032-033-038-042-047-051-058-063-082.
WIND CHILL WARNING FROM 1 PM SATURDAY TO 1 PM EST SUNDAY FOR
NYZ039>041-043-048>050-052>054-059>061-064>066-083-084.
MA...WIND CHILL WARNING FROM 1 PM SATURDAY TO 1 PM EST SUNDAY FOR
MAZ001-025.
VT...WIND CHILL WARNING FROM 3 AM SATURDAY TO 1 PM EST SUNDAY FOR
VTZ013>015.
&&
$$
SYNOPSIS...IRL/WASULA
NEAR TERM...11/WASULA
SHORT TERM...11
LONG TERM...ELH
AVIATION...IRL
HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
931 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC FRONT WILL CROSS THE AREA TONIGHT. HIGH PRESSURE WILL
BUILD ACROSS THE AREA LATER THIS WEEKEND AND THEN MOVE EAST
SUNDAY NIGHT. LOW PRESSURE WILL DEEPEN ACROSS THE LOWER MISSISSIPPI
VALLEY MONDAY AND THEN MOVE ALONG THE APPALACHIANS TUESDAY AND THEN
NORTH INTO CANADA WEDNESDAY. MORE HIGH PRESSURE WILL BUILD IN FOR
THE END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
ONE BAND OF SNOW SHOWERS IS EXITING OFF THE NJ CST. ANOTHER IS
MOVG THRU ERN PA ATTM. THE HRRR INDICATES THIS AREA WILL DISSIPATE
AS IT MOVES EWD. HOWEVER, THE HRRR DID NOT DO WELL WITH THE
EARLIER BAND SO CONFIDENCE IS LOW. WILL KEEP HIGH POPS W AND LWR
POPS FOR THE NEXT FEW HOURS FOR THIS BAND.
A STRONG CDFNT WILL CROSS THE REGION LATE TONIGHT THEN A WIND
SHIFT TO NORTHWEST AND GUSTY 20-30 MPH BY DAWN
SATURDAY....POSSIBLE ISOLATED GUSTS 40-45 MPH AT SUNRISE PER
ARRIVING STRONG CAA AND PRES RISES.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
WIND CHILL ADVY AND WIND ADVY POSTED IN ADDITION TO PRIOR WIND
CHILL WARNING. SPS FROM YDY NO LONGER NEEDED.
DEEPENING BOUNDARY LAYER MOMENTUM TRANSFER IS FEATURED ASSOCIATED
WITH THE ONCOMING ARCTIC AIRMASS INVASION. LARGE LOW LVL LAPSE
RATES AND BTV SNOW SQUALL PARAMETER INDICATING A POSSIBILITY OF
FLURRIES OR SQUALLS BUT WILL THE SFC TT/TD SPREAD EXCEED 25F AND
MAKE THOSE SQUALLS JUST VIRGA? SEEMS LIKE BEST CHC FOR A SQUALL
WOULD BE THE MORNING AND IN THE REGION S OF THE PA TURNPIKE.
AM THINKING OF GUSTS 50 MPH IN THE POCONOS AND ALSO SCATTERED 50
MPH GUSTS DEVELOPING IN THE KRDG-KPHL-KILG KACY AND NORTH SIDE OF
DE BAY SLOT FOR THE AFTN. WIND ADVY ISSUED. NOT SURE HOW MANY
NOTICED BUT THE NAM AND OP ECMWF HAVE BEEN A LITTLE CONSERVATIVE
ON WIND. JUST LOOKS LIKE TOO DEEP A MIXED LAYER TO AVOID CONNECTING
A FEW EDDIES OF 50 KT GUSTS DOWN FROM 6000 TO 7000 FT ALOFT. THE
INVERSION SINKS TO NEAR 850 MB LATE IN THE DAY SATURDAY.
STRONGEST WINDS ASIDE FROM THE INITIAL BURST NEAR 11-12Z, MAY BE
LATE AFTN AND EVENING. FOR NOW WANTED TO LIMIT ADVY ONLY TO THE
DAY AND IF ITS GUSTING 40 KT AT 3 PM SATURDAY, THEN SUSPECT IT CAN
GUST 40-45 KT THROUGH 10 PM. CONFIDENCE ON VERIFICATION IS
AVERAGE. THIS COULD BE OVERDONE BUT HAVE SEEN REPEATEDLY THE POCS
WIND MATCH THE OVERWATER WIND NEAR 44065, AND NW FLOW STRONGEST
GUSTS NEAR A RDG-PHL LINE. ALSO ADDED MD E SHORE ALONG THE STILL
WARM CHES BAY AND DELAWARE ALONG THE BAY FROM WILMINGTON TO LEWES
WHERE I THINK SOME HEFTY GUSTS COULD ADD TO THE CHILL.
OTHERWISE WIDESPREAD GUSTS 40 MPH SATURDAY WITH PARTLY TO MOSTLY
SUNNY SKIES .. TENDING TO CLEAR LATE DAY.
WINDS WERE DERIVED FROM THE GFS, THE TEMPS FROM THE NAM MOS BLENDED
WITH THE 2M TEMPS OF THE 12Z GFS/NAM. HRRX INDICATED NEAR 0 AT KMPO
AT 17Z SATURDAY...WITHOUT A WIND CHILL. CANT SEE IT MORE THAN 17F
AT PHL AT 18Z SAT...MAYBE EVEN A DEGREE OR 2 COLDER?.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
THE HEART OF THE ARCTIC AIR MASS WILL BE ACROSS THE AREA SATURDAY
NIGHT AND INTO SUNDAY. DANGEROUSLY COLD TEMPERATURES AND WIND CHILL
READINGS WILL BE ACROSS THE ENTIRE FORECAST AREA. NO PRECIPITATION
IS EXPECTED. WINDS WILL DIMINISH THROUGH THE DAY SUNDAY. LOW
TEMPERATURES SAT NIGHT AROUND -10 ACROSS THE FAR NORTH AND CLOSER TO
5 DEGREES ACROSS THE METRO PHILLY AREAS AND OVER THE DELMARVA. HIGH
TEMPS SUNDAY IN THE TEENS MOST AREAS...BUT SINGLE DIGITS OVER THE
SRN POCONOS. WIND CHILL READINGS -20 TO -32 FAR NORTH AND -5 TO -10
OVER THE DELMARVA.
THE NEXT STORM SYSTEM WILL DEEPEN ACROSS THE SOUTH MONDAY AND MOVE
UP THE INLAND EAST COAST TUESDAY/WEDNESDAY. THE TRACK OF THE SYSTEM
THAT SEEMS TO BE COMING INTO BETTER AGREEMENT AMONGST THE OP MODELS
FAVOR A LOW TRACK ACROSS THE CENTRAL/WESTERN PART OF OUR AREA. THIS
WILL ALLOW A DECENT FLOW OF WARMER AIR TO OVERSPREAD THE REGION. THE
PRECIPITATION WILL BEGIN ACROSS THE AREA MONDAY AS SNOW...BUT WILL
CHANGE TO RAIN LATER MON NIGHT AND REMAIN MOSTLY RAIN TUESDAY. THE
QPF COULD BE UP TO 2 INCHES OF RAIN IN MANY AREAS. THERE IS ALSO
SOME CHC FOR AN ACCUMULATING SNOW MONDAY ACROSS (MOST LIKELY)
ERN/NERN PA BEFORE THE CHANGE TO RAIN. EARLIEST PREDICTIONS FOR SNOW
ACCUMS WOULD BE AROUND 1-3 INCHES AT THIS POINT. THE DETAILS WILL BE
TUNED UP AS THE WEEKEND PROGRESSES.
THE STORM MOVES UP INTO CANADA WEDNESDAY AND WILL BE FOLLOWED BY HIGH
PRESSURE AND DRIER COOLER AIR FOR THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
VFR CONDS WILL CONTINUE. HOWEVER, BASED ON LATEST RADAR SHOWING
SOME ENHANCED ECHOES, HAVE MOVED UP THE TIMING OF THE SHSN. MUCH
OF ACTIVITY IS NOT REACHING THE GROUND, BUT AS CLOSE AS KPNE IS
REPORTING SOME -SN. SO FAR THE SHSN HAS BEEN LIGHT ENOUGH TO BE
VFR. HOWEVER, SOME MVFR CAN NOT BE RULED OUT, AND WILL CONTINUE TO
INCLUDE IN THE FCSTS.
SATURDAY...THE BIGGEST ISSUE AFFECTING AVIATION TRAVEL ON
SATURDAY WILL BE THE WINDS. BEHIND THE AFOREMENTIONED COLD FRONT,
THE WINDS WILL QUICKLY TURN TO THE WEST THEN NORTHWEST AND BECOME
VERY GUSTY. SUSTAINED WINDS WILL BE AROUND 15-20 KNOTS BY 12-15Z
AND INCREASE INTO THE AFTERNOON. WIND GUSTS FROM 25 KNOTS EARLY
WILL INCREASE TO NEAR 40 KNOTS BY THE AFTERNOON.
OUTLOOK...
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED. NORTHWEST
WINDS 10 TO 25 KNOTS WITH GUSTS 30-35 KNOTS EARLY, DIMINISHING
SOME OVERNIGHT INTO SUNDAY. GUSTS STILL 20-25 KNOTS OVERNIGHT INTO
EARLY SUNDAY.
MONDAY-MONDAY NIGHT...DEGRADING CONDITIONS WITH MVFR/IFR LIKELY
THROUGH THE DAY MONDAY INTO MONDAY NIGHT. SNOW POSSIBLY
BEGINNING MONDAY FOR MANY AREAS, POSSIBLY MIXING WITH RAIN AT
TIMES FOR SOME AREAS.
TUESDAY-TUESDAY NIGHT...WIDESPREAD MVFR/IFR CONDITIONS. WINDY.
WEDNESDAY...IMPROVING CONDITIONS. WINDY.
&&
.MARINE...
LULL IN THE WIND AND SEAS WILL END SHORTLY AFTER MIDNIGHT.
GALES AND FREEZING SPRAY WARNINGS-ADVISORIES POSTED. THE HEAVIEST
FREEZING SPRAY WILL BE MIDNIGHT TO 7 AM ALONG THE SHORE WHERE SSTS
NOW DOWN TO ABOUT 35-36F AND USED 35 FOR THE ZY THRESHOLD.
ISOLATED 50 KT GUSTS POSSIBLE SATURDAY IN FUNNELED NW WIND DOWN DE
BAY.
OUTLOOK...
SATURDAY-SATURDAY NIGHT...GALE WARNING CONTINUES WITH STRONG
NORTHWEST FLOW ACROSS THE AREA. FREEZING SPRAY ADVISORY REMAINS IN
EFFECT AS VERY COLD AIR AND STRONG WINDS WILL LEAD TO AT LEAST
MODERATE FREEZING SPRAY.
SUNDAY-SUNDAY NIGHT...GALE WARNING AND FREEZING SPRAY ADVISORY
CONTINUE INTO SUNDAY MORNING. HOWEVER, WINDS WILL DIMINISH THROUGH
THE DAY AND SUNDAY NIGHT AS HIGH PRESSURE BUILDS INTO THE AREA.
MONDAY...SUB-SCA CONDITIONS.
MONDAY NIGHT-WEDNESDAY...SMALL CRAFT ADVISORY CONDITIONS
LIKELY...GALES POSSIBLE AS STRONG LOW PRESSURE MOVES UP THE EAST
COAST.
&&
.HYDROLOGY...
BEFORE EVERYONE HEADS INTO THE WEEKEND, I WANTED TO BRING NEXT
WEEK`S STORM INTO LIGHT AND MENTION THAT THERE IS A POTENTIAL FOR
FLOODING ACROSS THE HSA. THERE`S STILL A LOT THAT NEEDS TO UNFOLD,
BUT THE 5-DAY WPC QPF OF 1.50 TO 2.50 INCHES OF LIQUID COMBINED WITH
ANOTHER 0.25 TO 0.50 INCH OF SWE ON THE GROUND WOULD VERY LIKELY
CAUSE NUISANCE LOW-LYING FLOODING AND POSSIBLY SOME MINOR TO
MODERATE RIVER FLOODING (RIVERS ASSOCIATED WITH OUR FORECAST
POINTS). THIS ASSUMES MOST, IF NOT ALL, THE PRECIPITATION FALLS AS
RAIN.
THE UNCERTAINTY THIS AFTERNOON IS LARGE. YESTERDAY AT THIS TIME, THE
PRECIPITATION WAS HEAVIEST TUESDAY AND TUESDAY NIGHT. NOW IT`S LATE
MONDAY NIGHT INTO TUESDAY. BESIDES TIMING, TRACK IS QUITE DIFFERENT
BETWEEN THE GFS AND EURO WITH THE EURO BEING FURTHER WEST AND MORE
LIQUIDY. TRACK WILL PLAY A ROLE IN TEMPS AND NOT ONLY AFFECT WHAT
TYPE OF PRECIPITATION FALLS, BUT ALSO AFFECT WHAT REMAINING SWE
MELTS. THERE`S ABOUT 0.25 TO 0.50 SCATTERED ACROSS THE AREA. I CAN
SAY WE ARE IN A BETTER SPOT THAN ON THE 3RD AND 4TH WHEN THERE WAS
IN EXCESS OF 2.00 OF SWE ALONG THE I-78 CORRIDOR. AS AN FYI, ONE OF
THE MAIN REASONS WE DIDN`T SEE THE FLOODING, THAT MODELS SUGGESTED,
ON THE 3RD AND 4TH WAS BECAUSE ALL THE SWE DID NOT RAPIDLY COME OUT
OF THE SNOWPACK. SNOWMELT CAN BE A TOUGH NUT TO CRACK.
WHILE THE LACK OF SWE IS LOOKING BETTER ACROSS THE HSA, NOT ALL THE
RIVERS HAVE RECEDED BACK TO WHERE THEY WERE PRIOR TO THE 3RD. SO
RIVERS WILL START HIGHER AND THE COLD THIS WEEKEND WILL SURELY GET
THE GROUND HARD FOR A VERY EFFICIENT RUNOFF.
SO THE TAKE AWAY HEADING INTO THE WEEKEND IS TO UNDERSTAND THAT IF
THE MONDAY INTO TUESDAY (OR TUESDAY INTO WEDNESDAY) EVENT IS ALL
LIQUID ACROSS THE AREA, LOW-LYING, POOR DRAINAGE FLOODING IS LIKELY
AND MINOR TO MODERATE RIVER FLOODING IS POSSIBLE. IF THE
PRECIPITATION STARTS OFF AS SNOW OR ICE, THE FLOODING THREAT
DECREASES. IF ALL SNOW FALLS, WE`RE POTENTIALLY JUST KICKING THE CAN
DOWN THE ROAD FOR FUTURE FLOODING. TIME WILL TELL.
&&
.CLIMATE...
NEAR RECORD COLD IS STILL EXPECTED FOR PORTIONS OF OUR AREA SUNDAY
MORNING, DESPITE THE MOS GUIDANCE...AND BY FAR THE COLDEST AIR OF
THE SEASON SO FAR.
BEST CHANCE FOR RECORD EQUALING OR EXCEEDING FOR VALENTINES DAY:
KABE, KTTN, KPHL AND KMPO.
RECORD LOW MAX`S CAN ONLY OCCUR FOR THIS EVENT ON SUNDAY THE 14TH,
IF THEN. THOSE HAVE BEEN ADDED RECENTLY BELOW.
SITE 2015-16 COLDEST SO FAR RECORD LOW FEB. 14TH ----RER LOW MAX
---------------------- --------------------
ABE 8 -1 IN 1979 14-1979
ACY 10 -6 IN 1979 13-1979
PHL 12 +2 IN 1979 14-1979
ILG 12 -4 IN 1979 13-1979
RDG 10 -4 IN 1983
TTN 9 0 IN 1916
GED 13 -7 IN 1979
MPO -1 -12 IN 1970
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL ADVISORY FROM 6 PM SATURDAY TO 9 AM EST SUNDAY FOR
PAZ060>062-070-071-101>106.
WIND ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR PAZ054-055-
060-061-070-071-101>106.
WIND CHILL WARNING FROM 6 AM SATURDAY TO 1 PM EST SUNDAY FOR
PAZ054-055.
NJ...WIND CHILL ADVISORY FROM 6 PM SATURDAY TO 9 AM EST SUNDAY FOR
NJZ007>010-012>027.
WIND ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR NJZ001-014-
016>027.
WIND CHILL WARNING FROM 6 AM SATURDAY TO 1 PM EST SUNDAY FOR
NJZ001.
DE...WIND CHILL ADVISORY FROM 6 PM SATURDAY TO 9 AM EST SUNDAY FOR
DEZ001-002.
WIND ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR DEZ001>004.
MD...WIND CHILL ADVISORY FROM 6 PM SATURDAY TO 9 AM EST SUNDAY FOR
MDZ008-012.
WIND ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR MDZ008-012-
015-020.
MARINE...HEAVY FREEZING SPRAY WARNING FROM MIDNIGHT SATURDAY NIGHT TO 9
AM EST SUNDAY FOR ANZ450>453.
GALE WARNING FROM 4 AM SATURDAY TO 10 AM EST SUNDAY FOR ANZ430-
431-450>455.
FREEZING SPRAY ADVISORY FROM 4 AM SATURDAY TO 10 AM EST SUNDAY
FOR ANZ430-431-454-455.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...DRAG/NIERENBERG
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...DRAG/NIERENBERG/O`HARA
MARINE...DRAG/O`HARA
HYDROLOGY...
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
955 AM EST THU FEB 11 2016
.SYNOPSIS...
HIGH PRESSURE WILL BUILD EASTWARD INTO THE REGION TODAY AND THEN
MOVE THROUGH THE REGION TONIGHT. AN ARCTIC COLD FRONTAL BOUNDARY
WILL THEN MOVE THROUGH THE AREA FRIDAY NIGHT. BY SUNDAY, ANOTHER
AREA OF HIGH PRESSURE WILL BUILD SOUTHWARD INTO THE REGION AS LOW
PRESSURE FORMS ACROSS THE SOUTHERN UNITED STATES BY MONDAY. THIS
AREA OF LOW PRESSURE WILL THEN TRACK UP THE EAST COAST TUESDAY INTO
WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
954 AM: MAY START HAMMERING I-80 AREA IN AN 11AM UPDATE...PENDING
A LITTLE MORE MODEL GUIDANCE. HRRR TRYING TO LATCH ONTO SNOW
SHOWERS IN MOST RECENT CYCLE...STILL WAY BEHIND REALITY.
930 AM ESTF: WE THINK 1 TO 2 INCHES POSSIBLE IN NARROW BANDS. ALREADY
UNCONFIRMED REPORT 1.5". HANDLING WITH SPS`S AND VIGOROUSLY
UPDATED LEGACY AND POINT CLICK PRODUCTS. SNOW MAP UPDATING NOW BUT
STILL GENERAL LESS THAN 1".
730 AM ESTF: UPDATED FOR THE SNOW BAND IN SE PA INTO SW NJ. ITS
PUTTING DOWN A DUSTING THAT IS CAUSING SOME TRAVEL DIFFICULTY. A
NOWCAST IS POSTED AS WELL UPDATED SNOWMAP AND FORECASTS FOR THIS
MORNING. NO MODEL HAS THIS..N PART ..IN PART LES BAND TRAILING
INTO OUR AREA. IF WE SEE VSBY 1 MI OR LESS WE WILL UPGRADE TO AN
SPS. OUR RADAR CONTINUES IN VCP31 TO BETTER SEE THE FINER DETAILS,
PLUS ITS LOW TOP AND VERY LOW WATER CONTENT.
FROM THE MID SHIFT BELOW...
FOR A RELATIVELY QUIET WEATHER DAY, STILL HAVE THREE MAIN STORIES TO
TALK ABOUT FOR THE TODAY PERIOD.
SNOW...AS MENTIONED BY THE PREVIOUS SHIFT, LOW TO MID LEVEL LAPSE
RATES WILL BE QUITE STEEP ACROSS THE POCONOS AND NORTHERN NJ THROUGH
AT LEAST MID DAY. IN ADDITION, THE MID AND UPPER LEVEL SHORT WAVE
TROUGH WILL BE CROSSING THE REGION THROUGH THIS TIME. THESE FACTORS
ARE CONDUCIVE FOR SCATTERED SNOW SHOWERS, OR MAYBE EVEN A FAST
MOVING SNOW SQUALL, ACROSS THE NORTHERN HALF OF OUR REGION. WITH
PERSISTENT DRY AIR ADVECTION, MOISTURE IS LIMITED. SO EVEN THOUGH
SNOW/LIQUID RATIOS COULD BE ABOVE NORMAL THANKS TO THE VERY COLD AIR
IN PLACE, STILL EXPECT SNOW ACCUMULATIONS TO REMAIN BELOW ONE INCH.
WINDS...A TIGHT PRESSURE GRADIENT WILL REMAIN OVER THE REGION
THROUGH AT LEAST 18Z BEFORE IT STARTS TO DECREASE AS THE SURFACE LOW
LIFTS FURTHER AWAY FROM OUR REGION. THUS, EXPECT WINDY CONDITIONS
THROUGH THE DAY. AT THIS POINT THOUGH, WIND ADVISORY CONDITIONS
(SUSTAINED WINDS OF AT LEAST 31 MPH FOR AT LEAST ONE HOUR OR GUSTS
OF 46 MPH) ARE NOT ANTICIPATED, SINCE THE TIGHTEST PRESSURE GRADIENT
WILL BE EARLY IN THE DAY BEFORE THE MIXING LAYER GETS VERY DEEP.
HAVING SAID THAT THOUGH, THE GFS DOES SHOW THAT THE SUSTAINED
CRITERIA COULD BE REACHED FOR LOCATIONS ADJACENT TO THE DE BAY,
SINCE THE DIRECTION IS A FAVORED DIRECTION FOR THE FUNNELING EFFECT
OVER THE BAY. IN ADDITION, VAD WIND PROFILES SHOW THAT 40 KT WINDS ARE
ABOUT 4000 TO 5000 FT MSL. IF THE MIXING LAYER GETS DEEP ENOUGH,
SOME OF THAT COULD MIX DOWN FOR THE HIGHEST TERRAIN IN THE POCONOS
AND NW NJ. FOR NOW THOUGH, CONFIDENCE IS LOW THAT IT WILL BE
REACHED SO WILL NOT ISSUE AN ADVISORY AT THIS TIME.
COLD...TODAY BEGINS THE COLD STRETCH WHICH WE ARE EXPECTING TO
CONTINUE INTO THE WEEKEND. WHILE TODAY WILL PROBABLY BE THE WARMEST
OF THE NEXT 4 DAYS, THE REGION SHOULD STAY BELOW FREEZING, AND
PORTIONS OF THE POCONOS AND NW NJ MAY NOT GET OUT OF THE TEENS.
THIS WILL BE 15 TO 20 DEGREES BELOW NORMAL. GIVEN THE WINDY
CONDITIONS, WIND CHILL VALUES ACROSS THE REGION WILL ONLY TOP OUT IN
THE TEENS AT BEST.
TONIGHT...HIGH BEGINS TO BUILD IN, AND CONSEQUENTLY WINDS
DIMINISH, AND CLOUDS WILL DISSIPATE. AS A RESULT, SHOULD SEE
CONSIDERABLE RADIATIONAL COOLING, WITH LOWS IN THE SINGLE DIGITS
AND TEENS AND WIND CHILL VALUES IN THE SINGLE DIGITS ABOVE AND
BELOW ZERO.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
RIGHT NOW SIMILAR TO THE PRIOR FORECAST THROUGH ANTICIPATE
BEEFING UP POPS LATE FRI DAY AFTERNOON IN THE POCONOS.
NO CHANGES ATTM FOR FRI NIGHT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
OUR UPDATED BRIEFING PACKAGE AT MIDDAY WILL INCLUDE MORE INFORMATION
ON THE UPCOMING DANGEROUS COLD, INCLUDING A POSSIBLE WIND CHILL
WATCH FOR SAT NIGHT WHICH IS ALREADY A HIGH CONFIDENCE LIKELIHOOD.
THE EXTENDED WILL FEATURE BOTH THE PROSPECTS FOR THE COLDEST AIR
OF THE SEASON CENTERED ON SUNDAY MORNING AND A STRENGTHENING LOW
PRESSURE SYSTEM TRACKING UP THE EAST COAST EARLY NEXT WEEK.
FRIDAY AND SATURDAY: HIGH PRESSURE WILL MOVE THROUGH THE REGION ON
FRIDAY. THIS HIGH PRESSURE SYSTEM WILL GIVE WAY TO ANOTHER ARCTIC
COLD FRONT FRIDAY NIGHT. THE COLD FRONT SHOULD PROVIDE ENOUGH
LIFT AND MOISTURE FOR SOME SCATTERED SNOW SHOWERS TO DEVELOP.
THESE MAY PRODUCE SOME LIGHT ACCUMULATIONS OF UNDER AN INCH.
BEHIND THE FRONT, IT WILL BE A VERY COLD AND WINDY PERIOD WITH
SOME ADDITIONAL SNOW SHOWERS AND/OR FLURRIES IN ASSOCIATION WITH
THE NW FLOW OFF OF THE EASTERN GREAT LAKES. THE FAVORED REGIONS TO
SEE SNOW SHOWERS ARE IN THE HIGH TERRAIN AREAS OF EASTERN PA AND
NW NJ. BUFKIT ANALYSIS YIELDS THE POTENTIAL FOR 30-40 MPH GUSTS
SATURDAY AFTERNOON ACROSS THE REGION WITH THE GFS BEING THE MOST
AGGRESSIVE WITH THE GUST POTENTIAL. THE STRONG CAA WILL NOT ALLOW
TEMPERATURES TO RISE MUCH DURING THE DAY.
SATURDAY NIGHT THROUGH SUNDAY NIGHT: ANOTHER POTENT AREA OF ARCTIC
HIGH PRESSURE WILL BUILD INTO THE REGION WITH THE COLDEST SHOT OF
AIR OF THE SEASON SO FAR. MODELING HAS BEEN HOLDING STEADY ON THE
IDEA THAT 850 MB TEMPERATURES LOOK TO DIVE BELOW -25C. WILL
NUDGE TEMPERATURES A COUPLE OF DEGREES COOLER THAN MOST ENSEMBLE
GUIDANCE THROUGH THE WEEKEND DUE TO THE DEGREE OF THE COLD AIR
BEING MODELED. STRONG NORTHWEST WIND GUSTS, THOUGH NOT AS STRONG
AS ON SATURDAY WILL CONTINUE IN THE WAKE OF THE DEPARTING SYSTEM.
THE COLD AND WIND WILL RESULT IN WIND CHILLS FROM -10 TO -30 BELOW
ZERO SATURDAY NIGHT AND SUNDAY MORNING. PLEASE TO MAKE SURE TO
PREPARE FOR THE COLD WEATHER THAT IS COMING. PREPARATIONS INCLUDE
CHECKING PIPES AND MAKING SURE YOUR VEHICLE IS IN GOOD WORKING
CONDITION. LOW TEMPERATURES SUNDAY MORNING WILL LIKELY NEAR OR
BELOW ZERO AS WELL. PLEASE REFER TO THE CLIMATE SECTION ON RECORD
POTENTIAL.
PRESIDENTS DAY THROUGH TUESDAY NIGHT: HIGH PRESSURE WILL GRADUALLY
MOVE EAST OF THE REGION AND WILL GIVE WAY TO A STORM SYSTEM THAT IS
CURRENTLY MODELED TO FORM ACROSS THE SOUTHERN UNITED STATES AND
INTENSIFY AS IT MOVES UP THE EAST COAST. THE 00Z 2/11 OPERATIONAL
MODELS HAVE NARROWED THE GOAL POSTS OF POSSIBLE TRACKS FROM
EARLIER MODEL RUNS. THIS ALSO MATCHES OR IS JUST EAST OF THE 12Z
2/10 ECMWF ENSEMBLE MEAN TRACK. THIS TRACK GOES FROM SOUTH CENTRAL
AL/GA NORTHEAST TO THE CAROLINA COASTLINE THEN DUE NORTH UP THE
EAST COAST INTO SOUTHERN NEW ENGLAND. TWO MAIN FEATURES ARE
PRESENT TO TRACK WITH REGARDS TO MODELS OR RESPECTIVE ENSEMBLES
CHANGING THE FORECAST TRACK OF THIS SYSTEM IN FUTURE RUNS. THIS
FIRST IS A LEADING SHORTWAVE WHICH MOVES INTO THE THE OHIO VALLEY
ON MONDAY AND THE SECOND IS THE DEGREE OF MID- LEVEL HEIGHT RISES
THAT OCCUR AHEAD OF THE STORM SYSTEM. A STRONGER SHORTWAVE WOULD
TEND TO PUSH THE OVERALL TROUGH WITH THIS STORM FURTHER EAST.
WHILE A WEAKER SHORTWAVE WOULD ALLOW FOR HIGHER MID- LEVEL HEIGHT
RISES LEADING TO A FURTHER WEST TRACK OF THE LOW. RIGHT NOW THE
FAVORED TRACK WOULD RESULT IN SNOW CHANGING TO RAIN ACROSS MOST OF
THE REGION WITH THE HIGHEST CHANCES FOR PRECIPITATION MONDAY NIGHT
AND TUESDAY. IT WILL LIKELY BE WINDY AS WELL WITH THE
STRENGTHENING LOW PRESSURE SYSTEM TRACKING NEAR THE REGION.
WEDNESDAY: THE REGION SHOULD GRADUALLY BEGIN TO CLEAR OUT AS
ANOTHER HIGH PRESSURE SYSTEM BUILDS EASTWARD TOWARD THE REGION.
SOME UNCERTAINTY THOUGH AS 2/11 00Z ECMWF BRINGS ANOTHER SYSTEM
INTO THE REGION BY THIS PERIOD.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR SCT-BKN AOA 4000 FT. BRIEF IFR CONDS IN SNOW SHOWERS
VCNTY KPHL NORTH THROUGH KTTN, KABE, AND KRDG. TIMING UNCERTAIN
AND HANDLING AS NEAR TERM FCST. THESE MESOSCALE BANDS DONT APPEAR
TO BE WELL HANDLED BY OUR HRRR HRRRX PRODUCTS NOR RUC/RAP. NEW
12Z/11 NAM HAS A NEW BAND DEVELOPING NEAR AND N OF I-80 THIS AFTN.
LATEST HRRR TRYING TO GRASP THE SITN. CERTAINLY VERY LARGE LOW LVL
LAPSE RATES AS COLD POOL ALOFT TEMPORARILY LIFTS ENE.
BASICALLY THERE APPEARS TO BE A LAKE EFFECT SNOW - MOISTURE PLUME
CONNECTION TO THE STILL WIDE OPEN LERIE, THEN SEWD INTO SWRN PA
AND FROM THERE EWD TO NEAR PHL. THAT MAY REFOCUS NEAR I-80 OR I-78
THIS AFTN.
WEST WIND GUSTS INCREASING TO 30 KT BY 16Z. ISOLATED 35 KT POSSIBLE.
TONIGHT...VFR SCT-BKN CLOUDS AOA 4000 FT DURING THE EVENING BECOMING
CLEAR. GUSTY WNW WINDS 20-30 KT SLOWLY DIMINISHING DURING THE
NIGHT.
FRIDAY...VFR.
OUTLOOK...
FRIDAY NIGHT AND SATURDAY: MAINLY VFR, POSSIBLE MVFR RESTRICTIONS
IN SCATTERED SNOW SHOWERS. NORTHWEST WINDS INCREASING SATURDAY
FROM 15-25 KNOTS WITH GUSTS UP TO 40 KNOTS SATURDAY AFTERNOON.
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED. NORTHWEST WINDS
10 TO 25 KNOTS.
MONDAY...VFR CONDITIONS FOR MOST OF THE DAY THEN BECOMING MVFR AND
IFR BY EVENING WITH RAIN AND SNOW.
&&
.MARINE...
GALES IN PROGRESS AND GLW CONTINUES AS POSTED. AN SCA WILL BE NEEDED
FOR MUCH IF NOT ALL OF THE OVER NIGHT HOURS ONCE THE GALES SUBSIDE.
LIGHT FREEZING SPRAY IS OCCURRING AND CONTINUES TO BE EXPECTED ON
THE BAY AS WELL AS THE NEAR COASTAL WATERS.
OUTLOOK...
OUR AFTERNOON MARINE PRODUCTS WILL HEADLINE A NEW HIGH CONFIDENCE
GALE WATCH FOR THE PERIOD ROUGHLY 4 AM SATURDAY THROUGH 8 AM SUNDAY.
SO WHILE, SEAS AND WINDS WILL START OUT FAIRLY LIGHT ON FRIDAY.
HOWEVER, A QUICK RAMP UP IS EXPECTED AFTER THE PASSAGE OF AN
ARCTIC COLD FRONTAL BOUNDARY FRIDAY NIGHT. NORTHWEST WINDS WILL
INCREASE AND REACH GALE FORCE BY SATURDAY AND CONTINUE GALE FORCE
THROUGH SATURDAY NIGHT. CONFIDENCE FOR GALES ON SATURDAY IS
VERY HIGH. SEAS WILL RISE TO BETWEEN 5 AND 7 FEET FOR A PERIOD AS
WELL ON SATURDAY. SEAS AND WINDS ARE EXPECTED TO DECREASE ON
SUNDAY. WAVE HEIGHTS WILL LIKELY START INCREASING AGAIN BY MONDAY
NIGHT IN RESPONSE TO A DEVELOPING LOW PRESSURE SYSTEM TO OUR
SOUTH.
&&
.CLIMATE...
NEAR RECORD COLD IS EXPECTED FOR PORTIONS OF OUR AREA SUNDAY
MORNING AND BY FAR THE COLDEST AIR OF THE SEASON SO FAR.
ANTICIPATING TEMPS THROUGHOUT OUR FORECAST AREA WITHIN SEVERAL
DEGREES OF ZERO (WIND IS THE EQUALIZER) ANYTIME FROM MIDNIGHT
THROUGH 8 AM SUNDAY EXCEPT COLDER KMPO (NEAR -12F). THIS HAS BEEN
ADVERTISED BY THE GFS/ECMWF 2M TEMPS CYCLICALLY SINCE AT LEAST THE
00Z/7 OPERATIONAL CYCLES. THEREFORE, BEST CHANCE FOR RECORD
EQUALING OR EXCEEDING FOR VALENTINES DAY THE 14TH WOULD BE KABE,
KTTN, KPHL AND KMPO.
SNOW COVER MAY HELP A BIT I-95 NORTHWESTWARD...AND WE`LL SEE
WHERE WE ARE WITH SNOW COVER BY THURSDAY EVENING. NEW DUSTINGS
APPEAR ON THE WAY THROUGH FRIDAY NIGHT.
PLEASE NOTE... GUIDANCE IN PART IS BEING CLIMO BIASED HIGHER THAN
WHAT THE ONCOMING GFS/ECMWF LITERAL AIRMASS AND 2M TEMPS ARE INDICATING
FOR SUNDAY MORNING. TEMPS SUNDAY MORNING IN THE URBAN AREAS SHOULD
BE ABOUT 25 COLDER THAN NORMAL. THAT MEANS GUIDANCE TEMPS FOR PHL
OF 5 AND 6 DEGREES APPEAR TOO WARM...ESPECIALLY WITH A NORMAL
PHILADELPHIA LOW ON SUNDAY OF 28.
HAVE SEEN THE 12Z/11 2M TEMPS FOR PHL...1 ABOVE RANGING DOWN TO
-11 AT KMPO AND AM LIKING THOSE VALUES AS WITHIN 2F OF THE
UPCOMING REALITY.
RECORD LOW MAX`S CAN ONLY OCCUR FOR THIS EVENT ON SUNDAY THE
14TH, IF THEN. THOSE HAVE BEEN ADDED RECENTLY BELOW.
SITE 2015-16 COLDEST SO FAR RECORD LOW FEB. 14TH ----RER LOW MAX
---------------------- --------------------
ABE 8 -1 IN 1979 14-1979
ACY 10 -6 IN 1979 13-1979
PHL 12 +2 IN 1979 14-1979
ILG 12 -4 IN 1979 13-1979
RDG 10 -4 IN 1983
TTN 9 0 IN 1916
GED 13 -7 IN 1979
MPO -1 -12 IN 1970
SO, THIS WILL BE WIND DRIVEN COLD WITH MANY AREAS EXPERIENCING
WIND CHILL VALUES OF 15 TO 25 BELOW ZERO...POSSIBLY 30 BELOW IN
THE HILLS AND MOUNTAINS OF NORTHWEST NEW JERSEY AND NORTHEAST
PENNSYLVANIA.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...GALE WARNING UNTIL 1 AM EST FRIDAY FOR ANZ450>455.
GALE WARNING UNTIL 11 PM EST THIS EVENING FOR ANZ430-431.
&&
$$
SYNOPSIS...FRANCK
NEAR TERM...DRAG 954
SHORT TERM...DRAG
LONG TERM...GAINES
AVIATION...DRAG/GAINES 954
MARINE...DRAG/GAINES
CLIMATE...954
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
930 AM EST THU FEB 11 2016
.SYNOPSIS...
HIGH PRESSURE WILL BUILD EASTWARD INTO THE REGION TODAY AND THEN
MOVE THROUGH THE REGION TONIGHT. AN ARCTIC COLD FRONTAL BOUNDARY
WILL THEN MOVE THROUGH THE AREA FRIDAY NIGHT. BY SUNDAY, ANOTHER
AREA OF HIGH PRESSURE WILL BUILD SOUTHWARD INTO THE REGION AS LOW
PRESSURE FORMS ACROSS THE SOUTHERN UNITED STATES BY MONDAY. THIS
AREA OF LOW PRESSURE WILL THEN TRACK UP THE EAST COAST TUESDAY INTO
WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
930 AM ESTF: WE THINK 1 TO 2 INCHES POSSIBLE IN NARROW BANDS. ALREADY
UNCONFIRMED REPORT 1.5". HANDLING WITH SPS`S AND VIGOROUSLY
UPDATED LEGACY AND POINT CLICK PRODUCTS. SNOW MAP UPDATING NOW BUT
STILL GENERAL LESS THAN 1".
730 AM ESTF: UPDATED FOR THE SNOW BAND IN SE PA INTO SW NJ. ITS
PUTTING DOWN A DUSTING THAT IS CAUSING SOME TRAVEL DIFFICULTY. A
NOWCAST IS POSTED AS WELL UPDATED SNOWMAP AND FORECASTS FOR THIS
MORNING. NO MODEL HAS THIS..N PART ..IN PART LES BAND TRAILING
INTO OUR AREA. IF WE SEE VSBY 1 MI OR LESS WE WILL UPGRADE TO AN
SPS. OUR RADAR CONTINUES IN VCP31 TO BETTER SEE THE FINER DETAILS,
PLUS ITS LOW TOP AND VERY LOW WATER CONTENT.
FROM THE MID SHIFT BELOW...
FOR A RELATIVELY QUIET WEATHER DAY, STILL HAVE THREE MAIN STORIES TO
TALK ABOUT FOR THE TODAY PERIOD.
SNOW...AS MENTIONED BY THE PREVIOUS SHIFT, LOW TO MID LEVEL LAPSE
RATES WILL BE QUITE STEEP ACROSS THE POCONOS AND NORTHERN NJ THROUGH
AT LEAST MID DAY. IN ADDITION, THE MID AND UPPER LEVEL SHORT WAVE
TROUGH WILL BE CROSSING THE REGION THROUGH THIS TIME. THESE FACTORS
ARE CONDUCIVE FOR SCATTERED SNOW SHOWERS, OR MAYBE EVEN A FAST
MOVING SNOW SQUALL, ACROSS THE NORTHERN HALF OF OUR REGION. WITH
PERSISTENT DRY AIR ADVECTION, MOISTURE IS LIMITED. SO EVEN THOUGH
SNOW/LIQUID RATIOS COULD BE ABOVE NORMAL THANKS TO THE VERY COLD AIR
IN PLACE, STILL EXPECT SNOW ACCUMULATIONS TO REMAIN BELOW ONE INCH.
WINDS...A TIGHT PRESSURE GRADIENT WILL REMAIN OVER THE REGION
THROUGH AT LEAST 18Z BEFORE IT STARTS TO DECREASE AS THE SURFACE LOW
LIFTS FURTHER AWAY FROM OUR REGION. THUS, EXPECT WINDY CONDITIONS
THROUGH THE DAY. AT THIS POINT THOUGH, WIND ADVISORY CONDITIONS
(SUSTAINED WINDS OF AT LEAST 31 MPH FOR AT LEAST ONE HOUR OR GUSTS
OF 46 MPH) ARE NOT ANTICIPATED, SINCE THE TIGHTEST PRESSURE GRADIENT
WILL BE EARLY IN THE DAY BEFORE THE MIXING LAYER GETS VERY DEEP.
HAVING SAID THAT THOUGH, THE GFS DOES SHOW THAT THE SUSTAINED
CRITERIA COULD BE REACHED FOR LOCATIONS ADJACENT TO THE DE BAY,
SINCE THE DIRECTION IS A FAVORED DIRECTION FOR THE FUNNELING EFFECT
OVER THE BAY. IN ADDITION, VAD WIND PROFILES SHOW THAT 40 KT WINDS ARE
ABOUT 4000 TO 5000 FT MSL. IF THE MIXING LAYER GETS DEEP ENOUGH,
SOME OF THAT COULD MIX DOWN FOR THE HIGHEST TERRAIN IN THE POCONOS
AND NW NJ. FOR NOW THOUGH, CONFIDENCE IS LOW THAT IT WILL BE
REACHED SO WILL NOT ISSUE AN ADVISORY AT THIS TIME.
COLD...TODAY BEGINS THE COLD STRETCH WHICH WE ARE EXPECTING TO
CONTINUE INTO THE WEEKEND. WHILE TODAY WILL PROBABLY BE THE WARMEST
OF THE NEXT 4 DAYS, THE REGION SHOULD STAY BELOW FREEZING, AND
PORTIONS OF THE POCONOS AND NW NJ MAY NOT GET OUT OF THE TEENS.
THIS WILL BE 15 TO 20 DEGREES BELOW NORMAL. GIVEN THE WINDY
CONDITIONS, WIND CHILL VALUES ACROSS THE REGION WILL ONLY TOP OUT IN
THE TEENS AT BEST.
&&
.SHORT TERM /FRIDAY/...
HIGH BEGINS TO BUILD IN, AND CONSEQUENTLY WINDS DIMINISH, AND CLOUDS
WILL DISSIPATE. AS A RESULT, SHOULD SEE CONSIDERABLE RADIATIONAL
COOLING, WITH LOWS IN THE SINGLE DIGITS AND TEENS AND WIND CHILL
VALUES IN THE SINGLE DIGITS ABOVE AND BELOW ZERO.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
OUR UPDATED BRIEFING PACKAGE AT MIDDAY WILL INCLUDE MORE INFORMATION
ON THE UPCOMING DANGEROUS COLD, INCLUDING A POSSIBLE WIND CHILL
WATCH FOR SAT NIGHT WHICH IS ALREADY A HIGH CONFIDENCE LIKELIHOOD.
THE EXTENDED WILL FEATURE BOTH THE PROSPECTS FOR THE COLDEST AIR
OF THE SEASON CENTERED ON SUNDAY MORNING AND A STRENGTHENING LOW
PRESSURE SYSTEM TRACKING UP THE EAST COAST EARLY NEXT WEEK.
FRIDAY AND SATURDAY: HIGH PRESSURE WILL MOVE THROUGH THE REGION ON
FRIDAY. THIS HIGH PRESSURE SYSTEM WILL GIVE WAY TO ANOTHER ARCTIC
COLD FRONT FRIDAY NIGHT. THE COLD FRONT SHOULD PROVIDE ENOUGH
LIFT AND MOISTURE FOR SOME SCATTERED SNOW SHOWERS TO DEVELOP.
THESE MAY PRODUCE SOME LIGHT ACCUMULATIONS OF UNDER AN INCH.
BEHIND THE FRONT, IT WILL BE A VERY COLD AND WINDY PERIOD WITH
SOME ADDITIONAL SNOW SHOWERS AND/OR FLURRIES IN ASSOCIATION WITH
THE NW FLOW OFF OF THE EASTERN GREAT LAKES. THE FAVORED REGIONS TO
SEE SNOW SHOWERS ARE IN THE HIGH TERRAIN AREAS OF EASTERN PA AND
NW NJ. BUFKIT ANALYSIS YIELDS THE POTENTIAL FOR 30-40 MPH GUSTS
SATURDAY AFTERNOON ACROSS THE REGION WITH THE GFS BEING THE MOST
AGGRESSIVE WITH THE GUST POTENTIAL. THE STRONG CAA WILL NOT ALLOW
TEMPERATURES TO RISE MUCH DURING THE DAY.
SATURDAY NIGHT THROUGH SUNDAY NIGHT: ANOTHER POTENT AREA OF ARCTIC
HIGH PRESSURE WILL BUILD INTO THE REGION WITH THE COLDEST SHOT OF
AIR OF THE SEASON SO FAR. MODELING HAS BEEN HOLDING STEADY ON THE
IDEA THAT 850 MB TEMPERATURES LOOK TO DIVE BELOW -25C. WILL
NUDGE TEMPERATURES A COUPLE OF DEGREES COOLER THAN MOST ENSEMBLE
GUIDANCE THROUGH THE WEEKEND DUE TO THE DEGREE OF THE COLD AIR
BEING MODELED. STRONG NORTHWEST WIND GUSTS, THOUGH NOT AS STRONG
AS ON SATURDAY WILL CONTINUE IN THE WAKE OF THE DEPARTING SYSTEM.
THE COLD AND WIND WILL RESULT IN WIND CHILLS FROM -10 TO -30 BELOW
ZERO SATURDAY NIGHT AND SUNDAY MORNING. PLEASE TO MAKE SURE TO
PREPARE FOR THE COLD WEATHER THAT IS COMING. PREPARATIONS INCLUDE
CHECKING PIPES AND MAKING SURE YOUR VEHICLE IS IN GOOD WORKING
CONDITION. LOW TEMPERATURES SUNDAY MORNING WILL LIKELY NEAR OR
BELOW ZERO AS WELL. PLEASE REFER TO THE CLIMATE SECTION ON RECORD
POTENTIAL.
PRESIDENTS DAY THROUGH TUESDAY NIGHT: HIGH PRESSURE WILL GRADUALLY
MOVE EAST OF THE REGION AND WILL GIVE WAY TO A STORM SYSTEM THAT IS
CURRENTLY MODELED TO FORM ACROSS THE SOUTHERN UNITED STATES AND
INTENSIFY AS IT MOVES UP THE EAST COAST. THE 00Z 2/11 OPERATIONAL
MODELS HAVE NARROWED THE GOAL POSTS OF POSSIBLE TRACKS FROM
EARLIER MODEL RUNS. THIS ALSO MATCHES OR IS JUST EAST OF THE 12Z
2/10 ECMWF ENSEMBLE MEAN TRACK. THIS TRACK GOES FROM SOUTH CENTRAL
AL/GA NORTHEAST TO THE CAROLINA COASTLINE THEN DUE NORTH UP THE
EAST COAST INTO SOUTHERN NEW ENGLAND. TWO MAIN FEATURES ARE
PRESENT TO TRACK WITH REGARDS TO MODELS OR RESPECTIVE ENSEMBLES
CHANGING THE FORECAST TRACK OF THIS SYSTEM IN FUTURE RUNS. THIS
FIRST IS A LEADING SHORTWAVE WHICH MOVES INTO THE THE OHIO VALLEY
ON MONDAY AND THE SECOND IS THE DEGREE OF MID- LEVEL HEIGHT RISES
THAT OCCUR AHEAD OF THE STORM SYSTEM. A STRONGER SHORTWAVE WOULD
TEND TO PUSH THE OVERALL TROUGH WITH THIS STORM FURTHER EAST.
WHILE A WEAKER SHORTWAVE WOULD ALLOW FOR HIGHER MID- LEVEL HEIGHT
RISES LEADING TO A FURTHER WEST TRACK OF THE LOW. RIGHT NOW THE
FAVORED TRACK WOULD RESULT IN SNOW CHANGING TO RAIN ACROSS MOST OF
THE REGION WITH THE HIGHEST CHANCES FOR PRECIPITATION MONDAY NIGHT
AND TUESDAY. IT WILL LIKELY BE WINDY AS WELL WITH THE
STRENGTHENING LOW PRESSURE SYSTEM TRACKING NEAR THE REGION.
WEDNESDAY: THE REGION SHOULD GRADUALLY BEGIN TO CLEAR OUT AS
ANOTHER HIGH PRESSURE SYSTEM BUILDS EASTWARD TOWARD THE REGION.
SOME UNCERTAINTY THOUGH AS 2/11 00Z ECMWF BRINGS ANOTHER SYSTEM
INTO THE REGION BY THIS PERIOD.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR SCT-BKN AOA 4000 FT. BRIEF IFR CONDS IN SNOW SHOWERS
VCNTY KPHL NORTH THROUGH TTN ABE AND RDG. TIMING UNCERTAIN AND
HANDLING AS NEAR TERM FCST. THESE MESOSCALE BANDS DONT APPEAR TO
BE WELL HANDLED BY OUR HRRR HRRRX PRODUCTS NOR RUC/RAP. NEW 12Z/11
NAM HAS A NEW BAND DEVELOPING NEAR AND N OF I-80 THIS AFTN.
BASICALLY A LES CONNECTION FROM LERIE SEWD INTO SRN PA AND THEN
EWD TO NEAR PHL. THAT MAY REFOCUS NEAR I80 OR I78 THIS AFTN.
WEST WIND GUSTS INCREASING TO 30 KT BY 16Z. ISOLATED 35 KT POSSIBLE.
TONIGHT...VFR SCT-BKN CLOUDS AOA 4000 FT DURING THE EVENING BECOMING
CLEAR. GUSTY WNW WINDS 20-30 KT SLOWLY DIMINISHING DURING THE
NIGHT.
OUTLOOK...
FRIDAY: VFR.
FRIDAY NIGHT AND SATURDAY: MAINLY VFR, POSSIBLE MVFR RESTRICTIONS
IN SCATTERED SNOW SHOWERS. NORTHWEST WINDS INCREASING SATURDAY
FROM 15-25 KNOTS WITH GUSTS UP TO 40 KNOTS SATURDAY AFTERNOON.
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED. NORTHWEST WINDS
10 TO 25 KNOTS.
MONDAY...VFR CONDITIONS FOR MOST OF THE DAY THEN BECOMING MVFR AND
IFR BY EVENING WITH RAIN AND SNOW.
&&
.MARINE...
GALES IN PROGRESS AND GLW CONTINUES AS POSTED. AN SCA WILL BE NEEDED
FOR MUCH IF NOT ALL OF THE OVER NIGHT HOURS ONCE THE GALES SUBSIDE.
LIGHT FREEZING SPRAY IS OCCURRING AND CONTINUES TO BE EXPECTED ON
THE BAY AS WELL AS THE NEAR COASTAL WATERS.
OUTLOOK...
OUR AFTERNOON MARINE PRODUCTS WILL HEADLINE A NEW HIGH CONFIDENCE
GALE WATCH FOR THE PERIOD ROUGHLY 4 AM SATURDAY THROUGH 8 AM
SUNDAY.
SO WHILE, SEAS AND WINDS WILL START OUT FAIRLY LIGHT ON FRIDAY.
HOWEVER, A QUICK RAMP UP IS EXPECTED AFTER THE PASSAGE OF AN
ARCTIC COLD FRONTAL BOUNDARY FRIDAY NIGHT. NORTHWEST WINDS WILL
INCREASE AND REACH GALE FORCE BY SATURDAY AND CONTINUE GALE FORCE
THROUGH SATURDAY NIGHT. CONFIDENCE FOR GALES ON SATURDAY IS
VERY HIGH. SEAS WILL RISE TO BETWEEN 5 AND 7 FEET FOR A PERIOD AS
WELL ON SATURDAY. SEAS AND WINDS ARE EXPECTED TO DECREASE ON
SUNDAY. WAVE HEIGHTS WILL LIKELY START INCREASING AGAIN BY MONDAY
NIGHT IN RESPONSE TO A DEVELOPING LOW PRESSURE SYSTEM TO OUR
SOUTH.
&&
.CLIMATE...
NEAR RECORD COLD IS EXPECTED FOR PORTIONS OF OUR AREA SUNDAY
MORNING AND BY FAR THE COLDEST AIR OF THE SEASON SO FAR.
ANTICIPATING TEMPS THROUGHOUT OUR FORECAST AREA WITHIN SEVERAL
DEGREES OF ZERO (WIND IS THE EQUALIZER) ANYTIME FROM MIDNIGHT
THROUGH 8 AM SUNDAY EXCEPT COLDER KMPO (NEAR -12F). THIS HAS BEEN
ADVERTISED BY THE GFS/ECMWF 2M TEMPS CYCLICALLY SINCE AT LEAST THE
00Z/7 OPERATIONAL CYCLES. THEREFORE, BEST CHANCE FOR RECORD
EQUALING OR EXCEEDING FOR VALENTINES DAY THE 14TH WOULD BE KABE,
KTTN, KPHL AND KMPO.
SNOW COVER MAY HELP A BIT I-95 NORTHWESTWARD...AND WE`LL SEE
WHERE WE ARE WITH SNOW COVER BY THURSDAY EVENING. NEW DUSTINGS
APPEAR ON THE WAY THROUGH FRIDAY NIGHT.
AS AN ADDED NOTE HERE... GUIDANCE IN PART IS BEING CLIMO BIASED
HIGHER THAN WHAT THE ONCOMING GFS/ECMWF LITERAL AIRMASS AND 2M
TEMPS ARE INDICATING FOR SUNDAY MORNING. TEMPS SUNDAY MORNING IN
THE URBAN AREAS SHOULD BE ABOUT 25 COLDER THAN NORMAL. THAT MEANS
GUIDANCE TEMPS FOR PHL OF 5 AND 6 DEGREES APPEAR TOO WARM...ESPECIALLY
WITH A NORMAL PHILADELPHIA LOW ON SUNDAY OF 28.
RECORD LOW MAX`S CAN ONLY OCCUR FOR THIS EVENT ON SUNDAY THE
14TH, IF THEN.
SITE 2015-16 COLDEST SO FAR RECORD LOW FEB. 14TH ----RER LOW MAX
---------------------- --------------------
ABE 8 -1 IN 1979 14-1979
ACY 10 -6 IN 1979 13-1979
PHL 12 +2 IN 1979 14-1979
ILG 12 -4 IN 1979 13-1979
RDG 10 -4 IN 1983
TTN 9 0 IN 1916
GED 13 -7 IN 1979
MPO -1 -12 IN 1970
SO, THIS WILL BE WIND DRIVEN COLD WITH MANY AREAS EXPERIENCING
WIND CHILL VALUES OF 15 TO 25 BELOW ZERO...POSSIBLY 30 BELOW IN
THE HILLS AND MOUNTAINS OF NORTHWEST NEW JERSEY AND NORTHEAST
PENNSYLVANIA.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...GALE WARNING UNTIL 1 AM EST FRIDAY FOR ANZ450>455.
GALE WARNING UNTIL 11 PM EST THIS EVENING FOR ANZ430-431.
&&
$$
SYNOPSIS...FRANCK
NEAR TERM...DRAG/JOHNSON 930A
SHORT TERM...JOHNSON
LONG TERM...GAINES
AVIATION...DRAG/GAINES/JOHNSON 930A
MARINE...DRAG/GAINES/JOHNSON 930A
CLIMATE...
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
859 PM CST FRI FEB 12 2016
.UPDATE...
ISSUED AT 859 PM CST FRI FEB 12 2016
Skies have become clear this evening and should remain that way
the rest of the night. Any additional clouds will be very late
tonight or early tomorrow morning and be cirrus clouds. Winds
remain gusty and am expecting this to continue as forecast as
well. Gusty winds will keep air mixed, but dewpoints are in the
single digits over most of the area, so still think temps by
morning will be in the single digits to just below zero in the
northwest. Only change needed is to adjust cloud cover to better
reflect current conditions. Update will be out shortly.
&&
.SHORT TERM...(Tonight)
ISSUED AT 255 PM CST FRI FEB 12 2016
A weak clipper system will exit southeast of central IL late this
afternoon, with its diminishing area of very light snow/flurries
se of the IL river ending soon, with best light snow chances east
of IL over central IN. MVFR clouds already scattering nw of the IL
river like at PIA and HRRR model handling this clearing well.
These clouds to decrease se of the IL river during late
afternoon/early evening, and over southeast IL by mid evening.
Brisk NW winds of 15-25 mph and gusts to 30 mph will gradually
diminish during the night, reaching 5-15 mph later tonight. Strong
1046 mb polar high pressure west of Lake Winnipeg Canada to settle
se into MN/IA by sunrise Sat and bring a frigid night to the
region. Lows by early Saturday morning range from around zero
north of I-72 to 4-8F in southeast IL from I-70 southeast. Wind
chills by dawn will range from 5-15 below zero with a few spots
from I-74 north dipping to 15-17 below zero like at Bloomington,
Galesburg and Champaign. Will hold off on a wind chill advisory
overnight into mid Sat morning, but will issue SPS to address
these bitter cold wind chills especially in our northern CWA.
.LONG TERM...(Saturday through Friday)
ISSUED AT 255 PM CST FRI FEB 12 2016
Very cold conditions expected to start the day Saturday across
central and southeast Illinois as Arctic high pressure builds across
the area. The relatively slight pressure gradient that will
accompany the surface high should keep Wind Chill values warmer than
advisory criteria for the most part, but high temperatures should
only top out in the teens.
Beyond the initially cold conditions, our attention turns to an
approaching clipper system, which is likely to be the most
significant weather system to impact the area over the next week.
This clipper has trended faster in recent model runs, with snow now
expected to start breaking locally after midnight Saturday
night/Sunday morning. The system will be pushing into a very dry
airmass which should limit the snow accumulation to some degree.
However, fairly strong isentropic ascent and mixing ratios of 2-3
G/KG over at least a 12 hour period should be able to produce 2"=4"
snow totals. In fact, would not be surprised if we need to boost
accumulations further once the exact track of the system is more
clear (it has trended s bit south in the latest runs). One other
thing that will need to be monitored is that the moisture depth is
progged to be rather shallow during the period of potential snow.
This fact is also a reason to limit snow accumulations for now, and
we also need to monitor the threat for freezing drizzle due to a
potential lack of ice crystals.
The faster trend of the clipper system should now have Monday ending
up dry. Another weak clipper system may impact the area Tuesday into
Tuesday night, but it does not appear significant at this time.
After that, the next chance for precipitation should not occur
before the end of the week. However, model agreement in the details
of the late week system is weak at best. Temperatures should
gradually be trending warmer next week, with well above normal
temperatures likely by the end of the week (near 50 degrees for
highs). If these trends hold, the late week system, if/when it
impacts the area, should be a rain producer.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
ISSUED AT 518 PM CST FRI FEB 12 2016
VFR conditions will continue at all TAF sites next 24hrs. Clouds
are clearing from the area so all sites will be SKC to start and
then continue that way remainder of the night and into tomorrow
morning. Models bring in some high cirrus tomorrow in advance of
the next weather system, so have added SCT250 at all sites from
morning and through the day. Main issue is the wind speeds...with
gusty winds continuing this evening and into the overnight hours.
Then winds taper and sites will loose the gusts. Tomorrow winds
should be around 12kts of less. Wind direction will continue to be
northwest through the next 24hrs.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Auten
SHORT TERM...07
LONG TERM...BAK
AVIATION...Auten
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
517 PM CST FRI FEB 12 2016
.SHORT TERM...(Tonight)
ISSUED AT 255 PM CST FRI FEB 12 2016
A weak clipper system will exit southeast of central IL late this
afternoon, with its diminishing area of very light snow/flurries
se of the IL river ending soon, with best light snow chances east
of IL over central IN. MVFR clouds already scattering nw of the IL
river like at PIA and HRRR model handling this clearing well.
These clouds to decrease se of the IL river during late
afternoon/early evening, and over southeast IL by mid evening.
Brisk NW winds of 15-25 mph and gusts to 30 mph will gradually
diminish during the night, reaching 5-15 mph later tonight. Strong
1046 mb polar high pressure west of Lake Winnipeg Canada to settle
se into MN/IA by sunrise Sat and bring a frigid night to the
region. Lows by early Saturday morning range from around zero
north of I-72 to 4-8F in southeast IL from I-70 southeast. Wind
chills by dawn will range from 5-15 below zero with a few spots
from I-74 north dipping to 15-17 below zero like at Bloomington,
Galesburg and Champaign. Will hold off on a wind chill advisory
overnight into mid Sat morning, but will issue SPS to address
these bitter cold wind chills especially in our northern CWA.
.LONG TERM...(Saturday through Friday)
ISSUED AT 255 PM CST FRI FEB 12 2016
Very cold conditions expected to start the day Saturday across
central and southeast Illinois as Arctic high pressure builds across
the area. The relatively slight pressure gradient that will
accompany the surface high should keep Wind Chill values warmer than
advisory criteria for the most part, but high temperatures should
only top out in the teens.
Beyond the initially cold conditions, our attention turns to an
approaching clipper system, which is likely to be the most
significant weather system to impact the area over the next week.
This clipper has trended faster in recent model runs, with snow now
expected to start breaking locally after midnight Saturday
night/Sunday morning. The system will be pushing into a very dry
airmass which should limit the snow accumulation to some degree.
However, fairly strong isentropic ascent and mixing ratios of 2-3
G/KG over at least a 12 hour period should be able to produce 2"=4"
snow totals. In fact, would not be surprised if we need to boost
accumulations further once the exact track of the system is more
clear (it has trended s bit south in the latest runs). One other
thing that will need to be monitored is that the moisture depth is
progged to be rather shallow during the period of potential snow.
This fact is also a reason to limit snow accumulations for now, and
we also need to monitor the threat for freezing drizzle due to a
potential lack of ice crystals.
The faster trend of the clipper system should now have Monday ending
up dry. Another weak clipper system may impact the area Tuesday into
Tuesday night, but it does not appear significant at this time.
After that, the next chance for precipitation should not occur
before the end of the week. However, model agreement in the details
of the late week system is weak at best. Temperatures should
gradually be trending warmer next week, with well above normal
temperatures likely by the end of the week (near 50 degrees for
highs). If these trends hold, the late week system, if/when it
impacts the area, should be a rain producer.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
ISSUED AT 518 PM CST FRI FEB 12 2016
VFR conditions will continue at all TAF sites next 24hrs. Clouds
are clearing from the area so all sites will be SKC to start and
then continue that way remainder of the night and into tomorrow
morning. Models bring in some high cirrus tomorrow in advance of
the next weather system, so have added SCT250 at all sites from
morning and through the day. Main issue is the wind speeds...with
gusty winds continuing this evening and into the overnight hours.
Then winds taper and sites will loose the gusts. Tomorrow winds
should be around 12kts of less. Wind direction will continue to be
northwest through the next 24hrs.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...07
LONG TERM...BAK
AVIATION...Auten
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
324 PM CST THU FEB 11 2016
.SHORT TERM...(Tonight)
ISSUED AT 323 PM CST THU FEB 11 2016
A fast moving clipper will produce light snow starting this evening
across western Illinois, with most of the focused lift overnight
primarily remaining across our southwestern counties. The general
trend in the 12z models has been to focus the better chances of
measurable snowfall over our southwestern and southern counties.
Have increased PoPs to likely in a narrow corridor southwest of a
line from Jacksonville to Effingham, progressing from SW to SE with
time overnight. The HRRR is the farthest southwest with the latest
updated path of forcing for precip, with the NAM80, Canadian GEM,
and ECMWF still extending at least some snow accumulation across all
of our CWA except the far NE counties NE of CMI. The NAM12 is
similar to the HRRR in limiting snow to the SW half of our CWA. Have
reduced the PoPs in our N and NE counties, north of I-74, to slight
chance. Chance PoPs were limited to generally south of a line from
Galesburg to Lincoln to Paris. Snow amounts from Jacksonville to
Effingham could reach between a half inch and one inch, with a
dusting to a half inch as far north as Rushville to Lincoln to
Decatur. South to southwest winds should remain less than 10 mph
during the snowfall, so drifting should not be a big problem
overnight.
Low temps tonight will generally settle out in the mid-teens, as
cloud cover limits the diurnal swing to only around a 10 degree drop-
off.
&&
.LONG TERM...(Friday through Thursday)
ISSUED AT 323 PM CST THU FEB 11 2016
Friday may start out with a few lingering snow showers south of
I-70, but little additional accumulation is expected after
sunrise. The bigger story will be the arrival of very cold air on
increasing northwest winds Friday afternoon, as strong pressure
rises develop ahead of the surface high center. The tight pressure
gradient will produce wind gusts over 30 mph at times, which could
cause minor drifting of the snowfall from tonight, so slippery
travel could develop from that Friday afternoon and evening.
Wind chills late Friday night will drop very close to advisory
levels of -15F north of Peoria, with wind chills below zero in all
of our forecast area. Actual air temps will be range from zero to 8
above zero, but NW winds will remain strong enough to push wind
chills well below zero.
The next main concern will be the system for Sunday into Monday.
Model differences remain with the 12z model updates. The Canadian
GEM has started showing the splitting of energy as the trough
reaches Illinois, similar to what the ECMWF was showing yesterday.
The ECMWF has changed and now maintains the trough energy across
Illinois Sunday evening, with total QPF amounts that support snow
amounts of 1 to 2". The Canadian GEM QPF amounts support around 1
inch west of I-55, with little to no snow accum east of I-55. The
GFS remains the only model that develops a distinct surface
low/circulation that tracks across northern IL Sunday evening, with
total QPF amounts that support snowfall of 4" to 7" in our northern
counties, and 3-4" in the south. The 12z NAM now includes forecast
info through 6 pm Sunday, and is showing plenty of snow as well,
despite no surface low moving across IL. The NAM has 3-5" across our
counties for just the first 12 hours of the event through 6 pm
Sunday. We have increased PoPs into the likely category for Sunday
nearly everywhere, and likely PoPs east of I-57 Sunday night.
Our compromise forecast for QPF came out to 0.23-0.30", correlating
to snowfall amounts of 2-4", with the higher totals from Peoria and
north. There still remains quite a bit of uncertainty with how much
moisture will fall, so updates to QPF and resultant snow accums are
likely with subsequent model runs.
The accumulating snows should primarily be done by Monday morning,
but lingering light snow or flurries could continue into afternoon.
If precip does linger into the afternoon, the snow may mix
with or change to rain.
All of the extended models show a low deepening south of Illinois on
Monday, and progressing up into the Appalachian mountains Monday
night, with precip mainly southeast of our area. However, the
blended initialization kept slight chance PoPs in the eastern half
of Illinois Monday night through Tuesday night, mainly due to that
strong system.
A warming trend is indicated for next week, as upper level ridging
gradually pushes east into Illinois. We should see mid-level warming
increase enough to support high temps climbing into the upper 30s to
low 40s Tuesday and Wed, with sunshine and mid 40s to around 50 for
Thursday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1155 AM CST THU FEB 11 2016
1030 MB Canadian high pressure over the upper MS river valley and
ridging into eastern IA and nw IL will slide se into eastern IL
and central/southern IN by 00Z/6 pm and into WV by 06Z/midnight
tonight. Nearby high pressure will continue light winds through
this evening across the central TAF sites. A northern stream short
wave/Alberta clipper over western SD will track se across MO
during this evening and into the TN valley by 12Z/6 am Friday.
Models have trended further sw track with this clipper so best
chances of light snow tonight have shifted sw into sw IL from SPI
sw. Have light snow/flurries with vsbys 4-6 miles and MVFR
ceilings spreading se along I-74 corridor 02-06Z. Steadier light
snow and vsbys down to 2-3 miles at DEC and especially SPI from
03Z-05Z along with MVFR ceilings. Light snow chances should end
late tonight from nw-se from 10-13Z as MVFR clouds linger. Light
winds this evening to become WNW by dawn Friday and increase to
10-15 kts with gusts 15-20 kts after 15Z/9 am Fri.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...Shimon
AVIATION...07
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1019 PM EST FRI FEB 12 2016
.SYNOPSIS...
ISSUED AT 1016 PM EST FRI FEB 12 2016
ARCTIC AIR WILL CONTINUE TO SPREAD ACROSS THE REGION OVERNIGHT
ACCOMPANIED BY GUSTY WINDS AND NUMEROUS LAKE EFFECT SNOW SHOWERS.
THE LAKE EFFECT SNOW WILL MAINLY IMPACT SOUTHWEST MICHIGAN AND
NORTH CENTRAL INDIANA WHERE 3 TO 6 INCHES OF ADDITIONAL
ACCUMULATION ARE EXPECTED TONIGHT AND SATURDAY. LOWS TONIGHT WILL
BE IN THE SINGLE DIGITS WITH HIGHS SATURDAY NEAR 15.
&&
.UPDATE...
ISSUED AT 734 PM EST FRI FEB 12 2016
POST FNTL SHSN WITHIN EMERGING ARCTIC AIRMASS QUITE INTENSE IN
SPOTS YET THIS EVENING BUT WILL CONT TO DIMINISH AS UNSTABLE SFC
BASED LAPSE RATES DECAY W/SUNSET. REGARDLESS GROWING QUITE CONCERNED
W/UPSTREAM LAKE RESPONSE WITHIN EVOLVING/INTENSIFYING LL THERMAL
TROUGH. GENERAL CONSOLIDATION IN BANDING NOTED OVR THE LAST 3 HOURS
ALG A MUSKEGON TO ALLEGAN LINE...MIMICKING RECENT RAP MODEL
INDICATIONS AS LL FLW VEERS CONSIDERABLY W/UPSTREAM EXTENT. THIS
PRIMARY PLUME XPCD/MODELED TO INTENSIFY AS IT COMES SOUTH THROUGH
LT EVENING BFR LOCKING IN WITHIN ROUGHLY ALG A SOUTH
HAVEN...CASSOPOLIS...ELKHART...WARSAW LINE. BASED ON OBSVD RADAR
TRENDS...SUSPECT NR 1" PER HOUR PEAK SNOWFALL RATES WHICH MAY
REQUIRE SOME FORM OF HEADLINE ADJUSTMENT. WILL ATTM FOLLOW
EVOLUTION OF THIS BAND THROUGH MID EVENING AND MAKE A DECISION IF
NEEDED WELL BFR 11 PM.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 306 PM EST FRI FEB 12 2016
CDFNT MOVG RAPIDLY E-SE ACROSS THE CWA THIS AFTN ACCOMPANIED BY A
BAND OF SNOW SHOWERS. LAKE EFFECT SNOW SHOWERS DVLPG BEHIND THE
FRONT SHOULD GRDLY INTENSIFY THIS EVE AS CAA CONTS AND WINDS VEER
FROM AROUND 300 DEGREES TO 340 DEGREES AS A SECONDARY CDFNT
CURRENTLY OVER NRN LWR MI MOVES THROUGH OUR AREA. INVERSION BASE
FORECAST TO PEAK LATE THIS EVE AROUND 6500FT WITH SIGNIFICANT LAKE
INDUCED INSTABILITY (0-2KM THETA-E LAPSE RATES OVER THE LAKE
AROUND -2.5C/KM). CONVECTION ALLOWING MODELS SUGGEST A DOMINANT
BAND OR TWO WILL SET UP AROUND THIS TIME IMPACTING NORTHWEST
PORTION OF OUR CWA. HWVR, THESE OPTIMAL CONDITIONS FOR LES SHOULD
BE SHORT LIVED AS INVERSION FCST TO LOWER/LAKE INDUCED INSTABILITY
DECREASE LATE TONIGHT AND THROUGH THE DAY SATURDAY. DGZ WILL ALSO
BE VERY LOW GIVEN ARCTIC AIRMASS MOVG IN WHICH SHOULD LIMIT ACCUMS
BLO WHAT OTRWS MIGHT BE EXPECTED. ONLY MINOR CHANGE MADE TO
PREVIOUS FCST ACCUMS WITH TOTALS TONIGHT AND SATURDAY EXPECTED TO
BE IN THE 3-6" RANGE IN THE ADVISORY AREA WITH 1-3" IN COUNTIES
SURROUNDING ADVISORY AND <1" OVER THE REST OF THE CWA. LOCALLY
HIGHER AMOUNTS PSBL IF DOMINANT BAND PERSISTS OVER ANY GIVEN AREA
VERY LONG THIS EVENING. BOUNDARY LAYER WINDS FCST 15-25KT TONIGHT
WHICH SHOULD CAUSE CONSIDERABLE BLOWING DRIFTING OF THE POWDERY
LES, MAINLY IN THE NW ADVISORY AREA. LITTLE CHANGE MADE TO TEMPS
WITH LOWS TONIGHT IN THE 0-5 RANGE NE AND SW WHERE SOME PARTIAL
CLEARING EXPECTED AND 5-10 UNDER THE LAKE EFFECT CLOUD PLUME OVER
MOST OF THE REST OF THE CWA, WITH HIGHS SATURDAY ONLY 12-16.
MINIMUM WIND CHILLS TONIGHT AND SATURDAY MORNING EXPECTED TO BE IN
THE -5 TO -15 RANGE.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 306 PM EST FRI FEB 12 2016
LAKE EFFECT SNOW WILL TAPER OFF SATURDAY EVENING AS LOW LEVEL RIDGE
AXIS SHIFTS OVERHEAD AND INVERSION HEIGHTS LOWER. DGZ REMAINS ACTIVE
IN THE 00-06Z TIMEFRAME SO SOME LIGHT FLURRIES/SNOW SHOWERS EXPECTED
BUT ANY ADDITIONAL ACCUMULATION WILL BE VERY LIGHT. MAIN STORY FOR
SATURDAY NIGHT WILL BE VERY COLD TEMPS. LIGHT WINDS...PARTIALLY
CLEAR SKIES...AND FRESH SNOW WILL SUPPORT GOOD RADIATIONAL COOLING
POTENTIAL IN SPOTS. GRADIENT WIND/WAA AND CLOUDS BEGIN TO INCREASE
TOWARD 12Z BUT SHOULD STILL BE ENOUGH TIME FOR TEMPS TO DROP. KEPT
CLOSE TO INHERITED FORECAST...WHICH IS ON THE COLD SIDE OF
GUIDANCE...WITH LOWS AROUND ZERO. WILL LIKELY BE A HIGH DEGREE OF
VARIANCE IN FINAL NUMBERS THOUGH...DEPENDING ON EXACT CLOUD TRENDS.
CHANCE FOR LIGHT SNOW THEN QUICKLY RETURNS LATE SUNDAY AS NEXT
SHORTWAVE ROTATES THROUGH THE REGION. CONFLUENT FLOW OVER THE
EASTERN CONUS WILL INCREASINGLY SHEAR OUT AND WEAKEN THIS WAVE. CVA
BECOMES NEGLIGIBLE BY SUNDAY NIGHT WITH JUST SOME BROAD/WEAK 280-
285K ISENTROPIC ASCENT. DO SEE A DECENT MOISTURE SURGE THOUGH WITH
MIXING RATIOS OVER 2 G/KG. GIVEN STEADY...ALBEIT WEAK...ASCENT AND
POTENTIAL FOR HIGHER THAN CLIMO SNOW RATIOS...COULD CHURN OUT 1-2"
BY LATE MONDAY MORNING. BEST CHANCES FOR HIGHER AMOUNTS WILL BE IN
OUR SOUTHWEST WHERE BETTER MOISTURE AND FORCING RESIDE.
AFTER A BRIEF BREAK MONDAY NIGHT...THERE IS ANOTHER CHANCE FOR SNOW
TUESDAY/TUESDAY NIGHT AS POTENT NORTHERN STREAM SHORTWAVE DIVES
SOUTHEAST AND STRENGTHENS EAST COAST LOW. MODELS HAVE BEEN KEEPING
PRECIP SHIELD OF PRIMARY LOW JUST EAST OF OUR CWA BUT CONTINUE TO
STRUGGLE IMMENSELY WITH EXACT TRACK OF SECONDARY VORT MAX.
CONFIDENCE IN SNOW CHANCES REMAINS LOW AT THIS POINT WITH PARENT JET
ENERGY STILL WELL OUT OVER THE DATA-SPARSE NORTH PACIFIC. WILL
CONTINUE TO WATCH THIS PERIOD AND ADJUST AS MODELS GET A BETTER
HANDLE ON SITUATION. SOME MINOR LAKE EFFECT THEN POSSIBLE WEDNESDAY
WITH MUCH WARMER TEMPS (AND POTENTIAL FOR RAIN) STILL EXPECTED BY
THE END OF THE WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 651 PM EST FRI FEB 12 2016
PRIMARY LAKE SNOW BANDING ALREADY WELL UNDERWAY FROM STONY POINT
SWD TO NR SAUGATUCK INLINE W/RAP TRENDS AS LL FLW CONTS TO VEER IN
WAKE OF SW PASSAGE. GIVEN GOOD CONTINUITY OF NR TERM MODEL SIGNALS
HAVE SHIFTED FWD TIME OF GREATEST IMPACT INVOF OF KSBN AND FULLY
XPC A PD OF LIFR CONDS TO MANIFEST AFT 06Z. INLAND REACH OF THIS
PRIMARY BAND MAY AFFECT FWA TERMINAL BRIEFLY PRIOR TO 06Z BUT OF
QUITE LIMITED DURATION AND LEFT OUT ATTM. WILL AMEND ACCORDINGLY
AS NEEDED.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 4 PM EST /3 PM CST/ SATURDAY FOR
INZ003>005.
MI...WINTER WEATHER ADVISORY UNTIL 4 PM EST SATURDAY FOR MIZ077>079.
OH...NONE.
LM...HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST SATURDAY FOR LMZ043-
046.
GALE WARNING UNTIL 7 AM EST SATURDAY FOR LMZ043-046.
&&
$$
UPDATE...T
SYNOPSIS...JT/SKIPPER
SHORT TERM...JT
LONG TERM...AGD
AVIATION...T
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
735 PM EST FRI FEB 12 2016
.SYNOPSIS...
ISSUED AT 306 PM EST FRI FEB 12 2016
AN ARCTIC FRONT WILL CONTINUE TO MOVE THROUGH THE AREA LATE THIS
AFTERNOON ACCOMPANIED BY NUMEROUS SNOW SHOWERS. LAKE EFFECT SNOW
AND BITTER COLD WILL FOLLOW THE ARCTIC FRONT TONIGHT AND
SATURDAY. THE LAKE EFFECT SNOW WILL MAINLY IMPACT SOUTHWEST
MICHIGAN AND NORTH CENTRAL INDIANA WHERE 3 TO 6 INCHES OF
ADDITIONAL ACCUMULATION ARE EXPECTED TONIGHT AND SATURDAY. LOWS
TONIGHT WILL BE IN THE SINGLE DIGITS WITH HIGHS SATURDAY NEAR 15.
&&
.UPDATE...
ISSUED AT 734 PM EST FRI FEB 12 2016
POST FNTL SHSN WITHIN EMERGING ARCTIC AIRMASS QUITE INTENSE IN
SPOTS YET THIS EVENING BUT WILL CONT TO DIMINISH AS UNSTABLE SFC
BASED LAPSE RATES DECAY W/SUNSET. REGARDLESS GROWING QUITE CONCERNED
W/UPSTREAM LAKE RESPONSE WITHIN EVOLVING/INTENSIFYING LL THERMAL
TROUGH. GENERAL CONSOLIDATION IN BANDING NOTED OVR THE LAST 3 HOURS
ALG A MUSKEGON TO ALLEGAN LINE...MIMICKING RECENT RAP MODEL
INDICATIONS AS LL FLW VEERS CONSIDERABLY W/UPSTREAM EXTENT. THIS
PRIMARY PLUME XPCD/MODELED TO INTENSIFY AS IT COMES SOUTH THROUGH
LT EVENING BFR LOCKING IN WITHIN ROUGHLY ALG A SOUTH
HAVEN...CASSOPOLIS...ELKHART...WARSAW LINE. BASED ON OBSVD RADAR
TRENDS...SUSPECT NR 1" PER HOUR PEAK SNOWFALL RATES WHICH MAY
REQUIRE SOME FORM OF HEADLINE ADJUSTMENT. WILL ATTM FOLLOW
EVOLUTION OF THIS BAND THROUGH MID EVENING AND MAKE A DECISION IF
NEEDED WELL BFR 11 PM.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 306 PM EST FRI FEB 12 2016
CDFNT MOVG RAPIDLY E-SE ACROSS THE CWA THIS AFTN ACCOMPANIED BY A
BAND OF SNOW SHOWERS. LAKE EFFECT SNOW SHOWERS DVLPG BEHIND THE
FRONT SHOULD GRDLY INTENSIFY THIS EVE AS CAA CONTS AND WINDS VEER
FROM AROUND 300 DEGREES TO 340 DEGREES AS A SECONDARY CDFNT
CURRENTLY OVER NRN LWR MI MOVES THROUGH OUR AREA. INVERSION BASE
FORECAST TO PEAK LATE THIS EVE AROUND 6500FT WITH SIGNIFICANT LAKE
INDUCED INSTABILITY (0-2KM THETA-E LAPSE RATES OVER THE LAKE
AROUND -2.5C/KM). CONVECTION ALLOWING MODELS SUGGEST A DOMINANT
BAND OR TWO WILL SET UP AROUND THIS TIME IMPACTING NORTHWEST
PORTION OF OUR CWA. HWVR, THESE OPTIMAL CONDITIONS FOR LES SHOULD
BE SHORT LIVED AS INVERSION FCST TO LOWER/LAKE INDUCED INSTABILITY
DECREASE LATE TONIGHT AND THROUGH THE DAY SATURDAY. DGZ WILL ALSO
BE VERY LOW GIVEN ARCTIC AIRMASS MOVG IN WHICH SHOULD LIMIT ACCUMS
BLO WHAT OTRWS MIGHT BE EXPECTED. ONLY MINOR CHANGE MADE TO
PREVIOUS FCST ACCUMS WITH TOTALS TONIGHT AND SATURDAY EXPECTED TO
BE IN THE 3-6" RANGE IN THE ADVISORY AREA WITH 1-3" IN COUNTIES
SURROUNDING ADVISORY AND <1" OVER THE REST OF THE CWA. LOCALLY
HIGHER AMOUNTS PSBL IF DOMINANT BAND PERSISTS OVER ANY GIVEN AREA
VERY LONG THIS EVENING. BOUNDARY LAYER WINDS FCST 15-25KT TONIGHT
WHICH SHOULD CAUSE CONSIDERABLE BLOWING DRIFTING OF THE POWDERY
LES, MAINLY IN THE NW ADVISORY AREA. LITTLE CHANGE MADE TO TEMPS
WITH LOWS TONIGHT IN THE 0-5 RANGE NE AND SW WHERE SOME PARTIAL
CLEARING EXPECTED AND 5-10 UNDER THE LAKE EFFECT CLOUD PLUME OVER
MOST OF THE REST OF THE CWA, WITH HIGHS SATURDAY ONLY 12-16.
MINIMUM WIND CHILLS TONIGHT AND SATURDAY MORNING EXPECTED TO BE IN
THE -5 TO -15 RANGE.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 306 PM EST FRI FEB 12 2016
LAKE EFFECT SNOW WILL TAPER OFF SATURDAY EVENING AS LOW LEVEL RIDGE
AXIS SHIFTS OVERHEAD AND INVERSION HEIGHTS LOWER. DGZ REMAINS ACTIVE
IN THE 00-06Z TIMEFRAME SO SOME LIGHT FLURRIES/SNOW SHOWERS EXPECTED
BUT ANY ADDITIONAL ACCUMULATION WILL BE VERY LIGHT. MAIN STORY FOR
SATURDAY NIGHT WILL BE VERY COLD TEMPS. LIGHT WINDS...PARTIALLY
CLEAR SKIES...AND FRESH SNOW WILL SUPPORT GOOD RADIATIONAL COOLING
POTENTIAL IN SPOTS. GRADIENT WIND/WAA AND CLOUDS BEGIN TO INCREASE
TOWARD 12Z BUT SHOULD STILL BE ENOUGH TIME FOR TEMPS TO DROP. KEPT
CLOSE TO INHERITED FORECAST...WHICH IS ON THE COLD SIDE OF
GUIDANCE...WITH LOWS AROUND ZERO. WILL LIKELY BE A HIGH DEGREE OF
VARIANCE IN FINAL NUMBERS THOUGH...DEPENDING ON EXACT CLOUD TRENDS.
CHANCE FOR LIGHT SNOW THEN QUICKLY RETURNS LATE SUNDAY AS NEXT
SHORTWAVE ROTATES THROUGH THE REGION. CONFLUENT FLOW OVER THE
EASTERN CONUS WILL INCREASINGLY SHEAR OUT AND WEAKEN THIS WAVE. CVA
BECOMES NEGLIGIBLE BY SUNDAY NIGHT WITH JUST SOME BROAD/WEAK 280-
285K ISENTROPIC ASCENT. DO SEE A DECENT MOISTURE SURGE THOUGH WITH
MIXING RATIOS OVER 2 G/KG. GIVEN STEADY...ALBEIT WEAK...ASCENT AND
POTENTIAL FOR HIGHER THAN CLIMO SNOW RATIOS...COULD CHURN OUT 1-2"
BY LATE MONDAY MORNING. BEST CHANCES FOR HIGHER AMOUNTS WILL BE IN
OUR SOUTHWEST WHERE BETTER MOISTURE AND FORCING RESIDE.
AFTER A BRIEF BREAK MONDAY NIGHT...THERE IS ANOTHER CHANCE FOR SNOW
TUESDAY/TUESDAY NIGHT AS POTENT NORTHERN STREAM SHORTWAVE DIVES
SOUTHEAST AND STRENGTHENS EAST COAST LOW. MODELS HAVE BEEN KEEPING
PRECIP SHIELD OF PRIMARY LOW JUST EAST OF OUR CWA BUT CONTINUE TO
STRUGGLE IMMENSELY WITH EXACT TRACK OF SECONDARY VORT MAX.
CONFIDENCE IN SNOW CHANCES REMAINS LOW AT THIS POINT WITH PARENT JET
ENERGY STILL WELL OUT OVER THE DATA-SPARSE NORTH PACIFIC. WILL
CONTINUE TO WATCH THIS PERIOD AND ADJUST AS MODELS GET A BETTER
HANDLE ON SITUATION. SOME MINOR LAKE EFFECT THEN POSSIBLE WEDNESDAY
WITH MUCH WARMER TEMPS (AND POTENTIAL FOR RAIN) STILL EXPECTED BY
THE END OF THE WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 651 PM EST FRI FEB 12 2016
PRIMARY LAKE SNOW BANDING ALREADY WELL UNDERWAY FROM STONY POINT
SWD TO NR SAUGATUCK INLINE W/RAP TRENDS AS LL FLW CONTS TO VEER IN
WAKE OF SW PASSAGE. GIVEN GOOD CONTINUITY OF NR TERM MODEL SIGNALS
HAVE SHIFTED FWD TIME OF GREATEST IMPACT INVOF OF KSBN AND FULLY
XPC A PD OF LIFR CONDS TO MANIFEST AFT 06Z. INLAND REACH OF THIS
PRIMARY BAND MAY AFFECT FWA TERMINAL BRIEFLY PRIOR TO 06Z BUT OF
QUITE LIMITED DURATION AND LEFT OUT ATTM. WILL AMEND ACCORDINGLY
AS NEEDED.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 4 PM EST /3 PM CST/ SATURDAY FOR
INZ003>005.
MI...WINTER WEATHER ADVISORY UNTIL 4 PM EST SATURDAY FOR MIZ077>079.
OH...NONE.
LM...HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST SATURDAY FOR LMZ043-
046.
GALE WARNING UNTIL 7 AM EST SATURDAY FOR LMZ043-046.
&&
$$
UPDATE...T
SYNOPSIS...JT
SHORT TERM...JT
LONG TERM...AGD
AVIATION...T
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
327 PM CST THU FEB 11 2016
.SYNOPSIS...
ISSUED AT 327 PM CST THU FEB 11 2016
HIGH PRESSURE CENTERED OVER THE EASTERN CWA THIS AFTERNOON AS
LEADING TO CLEAR SKIES AND DRY WEATHER FOR MOST OF THE AREA. A
FAST MOVING CLIPPER IS FORECAST TO AFFECT THE AREA LATER TODAY AND
TONIGHT AND WILL BE THE MAIN FORECAST CONCERN IN THE SHORT TERM
FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 327 PM CST THU FEB 11 2016
MAIN FORECAST CONCERN FOR THE SHORT TERM ARE THE CHANCES FOR SNOW
ASSOCIATED WITH A FAST CLIPPER ACROSS THE AREA TODAY. DRY AIR IN
PLACE WITH THE HIGH OVERHEAD WILL LIMIT OVERALL SNOWFALL TOTALS TO
AROUND AN INCH...WITH LOCALLY HIGHER AMOUNTS JUST OVER AN INCH.
HIRES GUIDANCE IS IN GOOD AGREEMENT THAT THIS WILL START NEAR 00Z
AND BE OUT OF THE AREA BY 08Z.
GUIDANCE TODAY HELD STRONG WITH THE CONSENSUS ON TIMING AND
STRONGEST FORCING WILL REMAIN ACROSS OUR FAR SOUTHERN ZONES. WWD
HAS AROUND AN INCH OF SNOW FOR THIS AREA AND OUR FORECAST
REPRESENTS THIS. LATEST RUNS OF THE HRRR SUGGESTS THAT THE BEST
SNOW WILL BE OUT OF THE AREA BY 06Z WITH LINGERING FLURRIES
THROUGH 09Z ACROSS THE FAR SOUTHERN CWA. WINDS WILL REMAIN LIGHT
SO LITTLE TO NO IMPACTS ARE EXPECTED FROM THIS SNOW. ANY SNOW THAT
ACCUMULATES SHOULD BE DONE BY THE EARLY HOURS.
FRIDAY WILL BE QUIET AND SLIGHTLY WARMER..WITH CLEARING SKIES.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 327 PM CST THU FEB 11 2016
FRIDAY NIGHT...LATEST SUITE OF 12Z RUN MODELS SUGGEST 1045 MB ARCTIC
HIGH PRESSURE STILL ON TRACK TO SURGE DOWN THE UPPER TO MID MS RVR
VALLEY FRI NIGHT INTO SAT WITH A SCOURING EFFECT. THIS FEATURE TO
COLD DUMP LLVL TEMPS/THICKNESS VALUES TO PRODUCE SUB-ZERO LOWS ACRS
MOST OF THE CWA...BUT SOME CONCERN THAT ONGOING MIXING SFC WINDS IN
INCOMING HIGH PRESSURE GRADIENT TO LIMIT A COMPLETE BOTTOM OUT.
BUT DUE TO BRUTE FORCE COLD AIR ADVECTION...WILL STILL GO WITH LOWS
FROM 5 TO NEAR 10 BELOW ZERO ACRS THE NORTHWESTERN THIRD OF THE
CWA...0 TO 5 BELOW ALONG AND NORTH OF I80...AND TO THE LOW SINGLE
DIGITS ABOVE ZERO IN THE SOUTHERN CWA. SFC WINDS DECREASING TO 7-10
MPH TOWARD SUNRISE SAT STILL TO PRODUCE ADVISORY LEVEL WIND CHILLS
ACRS AT LEAST THE NORTHWESTERN THIRD OF THE DVN CWA...AND POSSIBLY
ALONG THE HWY 20 CORRIDOR IN NW IL.
SATURDAY AND SUNDAY...THE ARCTIC HIGH OVERHEAD WILL MAKE FOR
TEMPORARY CLEAR AND CALM/LIGHT WIND CONDITIONS FOR FIRST PART OF THE
DAY SAT...WITH HIGH CLOUDS ON THE INCREASE AS THE AFTERNOON
PROGRESSES. THIS AHEAD OF THE ORGANIZING SHORT WAVE UPPER TROF THAT
WILL LOOK TO PROPAGATE TOWARD THE SOUTHWESTERN GRT LKS AND MID MS
RVR VALLEY ON SUNDAY IN BROADENING WEST-NORTHWESTERLY STEERING FLOW.
THE VARIOUS MEDIUM RANGE SOLUTIONS SUGGEST SOME TYPE OF ASSOCIATED
WARM AIR ADVECTION WING OF SNOW WILL LOOK TO TRY TO GET INTO THE
WESTERN OR SOUTHWESTERN CWA BY EARLY SAT EVENING...BUT FEEL MODELS
MAY BE TOO QUICK WITH THIS TAKING INTO ACCOUNT STRENGTH OF DRY SFC
RIDGE AXIS STILL ON THE MOVE OVER AND EAST OF THE CWA AT THAT TIME.
BUT BY MIDNIGHT SAT NIGHT...BOTH THE 12Z RUN ECMWF AND GEM SUGGEST
SOME LIGHT SNOW ACCUMS STARTING TO TAKE PLACE ALREADY IN THE FAR
SOUTHWESTERN CWA. AGAIN SIDING WITH THE 12Z GEM/ECMWF WHICH ARE IN
DECENT AGREEMENT...THE WAA WING OF SNOW AHEAD OF THE MAIN UPPER TROF
WILL LOOK TO CONTINUE TO SPREAD EASTWARD ACRS MUCH OF THE WESTERN
2/3S OF THE CWA THROUGH 12Z SUNDAY...BUT MAY GET ERODED SOME AS IT
DOES BY ONGOING DRY AIR IN PLACE AND ALSO SOME IMPACT OF MUCH OF THE
INITIAL LIFT GOING INTO THE TOP-DOWN SATURATION PROCESS. THE LATEST
GEM MAY HAVE THE BEST HANDLE ON THIS IDEA WITH JUST A DUSTING TO
HALF INCH WEST OF THE MS RVR BY 12Z SUNDAY...BUT WILL GO WITH A FEW
TENTHS TO NEAR AN INCH SOUTHWEST OF A LINE FROM DBQ...TO THE QUAD
CITIES...AND TO MACOMB IN WESTERN IL.
THEN THE MAIN SNOW EVENT WITH THE UPPER TROF WILL LOOK TO OCCUR ON
SUNDAY AND WILL CONTINUE TO ADJUST POPS UP INTO LIKELY OR EVEN
CATEGORICAL. BUT THE 12Z RUN AMERICAN MODELS/ESPECIALLY THE 12Z GFS/
WHICH HINT AT HIGH END ADVISORY OR EVEN LOW END WARNING CRITERIA
AMOUNT SNOWS BY SUNDAY EVENING COMBINING THE TWO SNOW MAKING
PROCESSES...SEEM TOO WET...TOO STRONG LOOKING AT MID AND UPPER LEVEL
JET DYNAMICS MORE FAVORABLE TO THE SOUTH...AND THEIR DEEP SATURATION
IN THE DENDRITIC GROWTH ZONE FOR MUCH OF SUNDAY MORNING INTO EARLY
AFTERNOON. SO CURRENTLY FAVOR A BLEND OF THE 12Z GEM/ECMWF MOISTURE
AND FORCING PROFILES WHICH SUGGEST MOST OF THE CWA TO GET 1-3 OR 2-4
INCHES OF SNOW BY SUNDAY EVENING. INCREASING SOUTH WINDS OF 15-20
MPH MAY PRODUCE SOME DRIFTING TROUBLE BY SUNDAY AFTERNOON AS
WELL...SO THERE MAY BE A NEED FOR AN EVENTUAL ADVISORY EVEN WITH THE
LIGHTER AMOUNTS PRODUCED BY THESE FAVORED SOLUTIONS. STILL 1-3 MORE
MODEL RUNS NEEDED TO FURTHER DEFINE THIS SNOW EVENT FOR MORE
CONFIDENCE.
MONDAY THROUGH NEXT THU...AS THE PASSING TROF CONTINUES TO EVOLVE
ALONG AND EAST OF THE REGION EARLY NEXT WEEK..RESULTANT MAJOR STORM
SHOULD TAKE OFF WELL TO THE EAST/SOUTHEAST OF LOCAL AREA OF CONCERN.
BUT THERE MAY BE SOME NUISANCE LIGHT SNOW AT TIMES ACRS THE AREA IN
THE WAKE OF THE MAIN SYSTEM...OR EVEN A SECONDARY WEAK CLIPPER LATE
MONDAY INTO TUE. LONGER RANGE INDICATIONS THEN SUGGEST THE CLIPPER
INDUCING NORTHWESTERLIES WILL EVENTUALLY GIVE WAY TO MILDER UPPER
RIDGING BY MID TO LATE NEXT WEEK...BUT THE TREND HAS BEEN TO DELAY
IT/S ARRIVAL ESPECIALLY IF RE-ENFORCING TROFFINESS ESTABLISHES ACRS
THE WESTERN GRT LKS TUE INTO WED LIKE SOME OF THE LATEST ENSEMBLES
SUGGEST. ..12..
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1132 AM CST THU FEB 11 2016
VFR CONDITIONS GIVING WAY TO MVFR CIGS AND POSSIBLY IFR VSBYS
DURING SNOW LATE THIS AFTERNOON AND THROUGH THE EVENING IS
EXPECTED AT MOST TAF SITES. BRL HAS THE BEST CHANCE FOR SNOW.
OTHERWISE WINDS SHOULD TURN TO THE SW AND THEN THE WNW LATE IN THE
PERIOD INTO TOMORROW WHERE SOME STRONG SUSTAINED WINDS ARE
POSSIBLE WITH GUSTS POSSIBLY TO 25KT. VFR CONDITIONS SHOULD RETURN
BY 09Z AT MOST TAF SITES.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...12
AVIATION...GIBBS
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
1119 AM CST THU FEB 11 2016
...Updated for Aviation...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CST THU FEB 11 2016
High pressure sinking south through the plains states will affect
temperatures to the negative side over the next couple of days.
Stratus was advancing across the Missouri valley into central
Nebraska and northern Kansas. The latest HRRR model runs have
continued to advect stratus of around 1000ft bases through the Hays
area and perhaps as far south as Dodge City after 12 UTC. So
stratus dissipation and local visibilities due to fog may be the
main forecast problems of the morning influencing temperature
trends. Afternoon highs will be not as warm today, however drier dew
points and downslope trajectories should still help temperatures
warm toward 70 in the far west.
.LONG TERM...(Friday THROUGH Wednesday)
ISSUED AT 346 AM CST THU FEB 11 2016
Very low precipitation probabilities were included associated with
mainly a freezing drizzle and fog possibility on Friday night into
very early Saturday morning, however, this only glances the
northwest most sections of west central Kansas as the model signal
is focused over the northwest part of the state. A general cooling
trend each day ends by Sunday as the easterly surface wind gets
whipped around from the west once again as a shortwave dives through
the Northern Plains. A short period of weakly cyclonic flow aloft
will continue into the Monday timeframe and pops may need to be
revisited in the coming forecast cycles, but at this point the
confidence is extremely low for precipitation chances.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Friday AFTERNOON)
ISSUED AT 1113 AM CST THU FEB 11 2016
Some low stratus at KHYS is forecast to dissipate early this
afternoon, then reform early Friday am after 12Z as wind shifts
back to the light north-northeast. Elsewhere expect VFR with light
south to southwest winds shifting northwesterly at 5-12kt after
00-03Z as a weak surface trough moves across western Kansas.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 57 31 51 22 / 0 0 0 10
GCK 61 29 53 24 / 0 0 0 10
EHA 67 33 59 29 / 0 0 0 10
LBL 63 31 58 26 / 0 0 0 10
HYS 49 30 42 20 / 0 0 0 20
P28 54 32 52 22 / 0 0 0 10
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Kruse
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
541 AM CST THU FEB 11 2016
...Updated aviation discussion...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CST THU FEB 11 2016
High pressure sinking south through the plains states will affect
temperatures to the negative side over the next couple of days.
Stratus was advancing across the Missouri valley into central
Nebraska and northern Kansas. The latest HRRR model runs have
continued to advect stratus of around 1000ft bases through the Hays
area and perhaps as far south as Dodge City after 12 UTC. So
stratus dissipation and local visibilities due to fog may be the
main forecast problems of the morning influencing temperature
trends. Afternoon highs will be not as warm today, however drier dew
points and downslope trajectories should still help temperatures
warm toward 70 in the far west.
.LONG TERM...(Friday THROUGH Wednesday)
ISSUED AT 346 AM CST THU FEB 11 2016
Very low precipitation probabilities were included associated with
mainly a freezing drizzle and fog possibility on Friday night into
very early Saturday morning, however, this only glances the
northwest most sections of west central Kansas as the model signal
is focused over the northwest part of the state. A general cooling
trend each day ends by Sunday as the easterly surface wind gets
whipped around from the west once again as a shortwave dives through
the Northern Plains. A short period of weakly cyclonic flow aloft
will continue into the Monday timeframe and pops may need to be
revisited in the coming forecast cycles, but at this point the
confidence is extremely low for precipitation chances.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Friday MORNING)
ISSUED AT 541 AM CST THU FEB 11 2016
IFR stratus is currently spreading south toward central Kansas. It
should be moving into the Hays area shortly after the beginning of
this TAF issuance. The stratus should impact operations through the
morning hours but should erode east of the area by midday. Do not see
the stratus moving too much more to the southwest so Garden City and
Dodge City should remain VFR.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 57 31 51 22 / 0 0 0 10
GCK 61 29 53 24 / 0 0 0 10
EHA 66 33 59 29 / 0 0 0 10
LBL 62 31 58 26 / 0 0 0 10
HYS 49 30 42 20 / 0 0 0 20
P28 54 32 52 22 / 0 0 0 10
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Gerard
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
348 AM CST THU FEB 11 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CST THU FEB 11 2016
High pressure sinking south through the plains states will affect
temperatures to the negative side over the next couple of days.
Stratus was advancing across the Missouri valley into central
Nebraska and northern Kansas. The latest HRRR model runs have
continued to advect stratus of around 1000ft bases through the Hays
area and perhaps as far south as Dodge City after 12 UTC. So
stratus dissipation and local visibilities due to fog may be the
main forecast problems of the morning influencing temperature
trends. Afternoon highs will be not as warm today, however drier dew
points and downslope trajectories should still help temperatures
warm toward 70 in the far west.
.LONG TERM...(Friday THROUGH Wednesday)
ISSUED AT 346 AM CST THU FEB 11 2016
Very low precipitation probabilities were included associated with
mainly a freezing drizzle and fog possibility on Friday night into
very early Saturday morning, however, this only glances the
northwest most sections of west central Kansas as the model signal
is focused over the northwest part of the state. A general cooling
trend each day ends by Sunday as the easterly surface wind gets
whipped around from the west once again as a shortwave dives through
the Northern Plains. A short period of weakly cyclonic flow aloft
will continue into the Monday timeframe and pops may need to be
revisited in the coming forecast cycles, but at this point the
confidence is extremely low for precipitation chances.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Thursday NIGHT)
ISSUED AT 1134 PM CST WED FEB 10 2016
VFR category is forecast with fairly high confidence at GCK.
However IFR category may be possible at HAYS toward the 11-14Z
timeframe as the cooler airmass over the Missouri valley advects
stratus clouds westward. Winds remain light through the period.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 57 31 51 22 / 0 0 0 10
GCK 61 29 53 24 / 0 0 0 10
EHA 66 33 59 29 / 0 0 0 10
LBL 62 31 58 26 / 0 0 0 10
HYS 49 30 42 20 / 0 0 0 20
P28 54 32 52 22 / 0 0 0 10
&&
.DDC Watches/Warnings/Advisories...NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS GRAY ME
1024 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL CROSS THE REGION TONIGHT THROUGH SATURDAY
USHERING IN THE COLDEST AIRMASS OF THE SEASON THUS FAR. AS THIS
COLD AIR INTERACTS WITH A TROUGH OF LOW PRESSURE OVER THE GULF OF
MAINE...A PERIOD OF MODERATE TO HEAVY SNOW WILL BE POSSIBLE ALONG
THE MIDCOAST REGION OF MAINE. BEYOND THIS...THE COMBINATION OF COLD
TEMPERATURES AND STRONG NORTHWEST WINDS WILL CAUSE DANGEROUSLY COLD
WIND CHILLS SATURDAY NIGHT AND SUNDAY. TEMPERATURES WILL RAPIDLY
MODERATE NEXT WEEK WITH A WINTRY MIX OF PRECIPITATION POTENTIALLY
TRANSITIONING TO RAIN ON MONDAY NIGHT AND TUESDAY ALONG WITH STRONG
SOUTHERLY WINDS.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
1015 PM UPDATE...HAVE MADE THE TRANSITION TO WINTER STORM WARNINGS
AND ADVISORIES FOR THE MID COAST OF MAINE BASED ON THE LATEST
SREF...NAM...4 KM NAM...HRRR...AND RAP. MUCH IF NOT ALL OF THE
EVENING GUIDANCE HAS SHIFTED TO THE SOUTHWEST WITH THE AXIS OF THE
NORLUN TROF AND SUBSEQUENT HEAVY SNOW BAND. THERE IS STILL
CONSIDERABLE UNCERTAINTY AS THERE ALWAYS IS RIGHT UP TO THE BUZZER
WITH THESE MESOSCALE FEATURES. HOWEVER...BASED ON A BLEND OF
GUIDANCE THAT REFLECTS A REAL SW TREND...FELT CONFIDENT ENOUGH TO
SHIFT THE SNOW AXIS SOUTHWESTWARD AS WELL. THE RESULT IS A WINTER
STORM WARNING FOR COASTAL WALDO AND KNOX COUNTIES. A WINTER
WEATHER ADVISORY HAS BEEN ISSUED FOR INTERIOR WALDO AND LINCOLN
COUNTIES. AGAIN...CONSIDERABLE UNCERTAINTY REMAINS...AND THERE IS
EVEN SOME CHANCE THAT THE HEAVIEST SNOW REMAINS ON THE PENINSULAS
AND ISLANDS...AND PERHAPS EVEN FURTHER EAST THAN THAT. IF IT
APPEARS AS THOUGH THE HEAVIEST SNOW WILL SHIFT FURTHER NORTH AND
WEST...THE ADVISORIES COULD BE UPGRADED TO WARNINGS.
635 PM UPDATE...HAVE CONTINUED TO POUR OVER LATEST OBERVATIONAL
AND MESOSCALE MODEL DATA EARLY THIS EVENING TO TRY AND PIN DOWN
THE FORMATION AND MOVEMENT OF AN INVERTED TROF THAT MAY BRING
HEAVY SNOWFALL TO A PORTION OF THE MID COAST. UNFORTUNATELY AT
THIS TIME IT IS A LITTLE TO EARLY TO SEE ANYTHING SIGNIFICANT IN
THE LATEST OBSERVATIONAL DATA SUCH AS BUOYS AND RADAR. AS FAR AS
THE MESOSCALE MODELS GO...THERE IS STILL A LOT OF SPREAD IN WHERE
THIS BAND WILL /OR WILL NOT/ DEVELOP OVER LAND. THE LATEST RUNS OF
THE NAM AND RGEM AS WELL AS THE 2.5 KM CANADIAN HIT KNOX AND
WALDO COUNTIES PRETTY HARD. HOWEVER...THE LATEST RUNS OF THE HRRR
AND RAP KEEP MUCH OF THE ACCUMULATING SNOWFALL OFFSHORE EXCEPT
PERHAPS THE PENINSULAS AND ISLANDS OF THE MID COAST. WITH SO MUCH
UNCERTAINTY REMAINING AND NO SIGN OF DEVELOPMENT YET IN
OBSERVATIONAL DATA...CAN/T REALLY JUSTIFY A WINTER STORM WARNING.
WILL HOLD ONTO THE WATCH FOR A FEW MORE HOURS. WILL LIKELY MAKE A
DECISION BY 10 PM...AND IF THERE IS STILL A LOT OF UNCERAINTY BY
THEN WE MAY JUST GO WITH AN ADVISORY AND LET THE NEXT SHIFT
UPGRADE TO A WARNING IF NEED BE.
PREVIOUSLY...
HIGH IMPACT WEATHER POTENTIAL: SNOW DEVELOPS ALONG THE MIDCOAST
OVERNIGHT. CURRENT PATTERN: EARLY AFTERNOON WATER VAPOR IMAGERY
REVEALS RIDGE- TROUGH PATTERN ACROSS THE CONUS...WITH IMPRESSIVE
PORTION OF THE POLAR VORTEX CURRENTLY CENTERED OVER JAMES BAY.
SOUTH OF THIS FEATURE...WATER VAPOR IMAGERY DEFINES A DIGGING
SHORTWAVE /DARKENING OF THE IMAGERY/ OVER THE NORTHERN OHIO
VALLEY. THIS WILL HELP FORCE CYCLOGENESIS OFF THE MID ATLANTIC
COAST THAT WILL RACE NORTHEAST WELL SOUTH AND EAST OF NEW ENGLAND
THROUGH SATURDAY. A WEAKER SURFACE LOW IS CURRENTLY DEPICTED OVER
THE EASTERN GREAT LAKES ASSOCIATED WITH FORCING AHEAD OF THE H5
LOW OVER JAMES BAY. AS THIS LATTER FEATURE DIVES SOUTH AND EAST
TOWARDS NEW ENGLAND THIS WEEKEND...THE ASSOCIATED SURFACE LOW WILL
BE ABSORBED INTO THE DEVELOPING SYSTEM OFFSHORE. OUR PRIMARY
WEATHER IMPACTS WILL BE 1- WHAT HAPPENS BETWEEN THESE SYSTEMS AS
IMPRESSIVE MID AND UPPER LEVEL FORCING COMBINES WITH VERY
SUBSTANTIAL INSTABILITY OVER THE RELATIVELY WARM GULF OF MAINE
WATERS AND 2- THE RAMIFICATIONS OF ARRIVING ARCTIC AIR. TEMPS AT
H8 THIS MORNING WERE -35C OVER JAMES BAY WITH TEMPERATURES CLOSE
TO THIS REACHING NEW ENGLAND ON SATURDAY...PRESENTING WIND CHILL
CONCERNS AS IMPRESSIVE COLD ADVECTION DRIVES THIS AIR INTO THE
REGION.
TONIGHT: EXPECT A GENERAL INCREASE IN MID AND UPPER LEVEL
CLOUDINESS PER A LOOK AT AFTERNOON VISIBLE SATELLITE IMAGERY AS
WEAK WARM ADVECTION CONTINUES AHEAD OF APPROACHING SURFACE LOW NOW
NORTH OF LAKE ONTARIO. FORCING FOR ASCENT WILL BE ON THE INCREASE
WITH TOP DOWN SATURATION LIKELY BRINGING SNOW SHOWER ACTIVITY INTO
THE MOUNTAINS OVERNIGHT. WE/LL TALK MORE ABOUT THE NORLUN EVENT IN
THE SHORT TERM SECTION BELOW...BUT EXPERIMENTAL HRRR IS ON BOARD
WITH THE 12Z GUIDANCE SUITE IN DEVELOPING LLEVEL CONVERGENCE IN THE
VICINITY OF PENOBSCOT BAY BY MIDNIGHT TONIGHT...WITH SNOW DEVELOPING
IN THIS REGION AND CONTINUING THROUGH THE MORNING. WITH A GOOD
FLUFF FACTOR HELPING ACCUMULATIONS...COULD SEE 1-3 INCHES OVER
KNOX/WALDO COUNTIES BY DAYBREAK.
TEMPERATURES: WITH SOUTHWEST FLOW ONGOING AND CLOUDS ON THE
INCREASE...TEMPERATURES WILL BE A GOOD BIT WARMER THAN THE PREVIOUS
NIGHT BUT GIVEN THE CHILLY HIGHS OF TODAY...WILL CERTAINLY NOT BE
WARM. EXPECT LOWS IN THE SINGLE DIGITS IN THE MOUNTAINS THROUGH THE
LOWER TEENS ALONG THE COAST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
SIGNIFICANT SNOW ALONG THE MID COAST BECOMING INCREASINGLY
LIKELY SATURDAY...
DANGEROUSLY COLD WIND CHILLS SATURDAY NIGHT THROUGHOUT THE
REGION...
HIGH IMPACT WEATHER POTENTIAL: HEAVY SNOW TOTALS POSSIBLE IN THE
VICINITY OF PENOBSCOT BAY SATURDAY WITH ATTENTION THEN TURNING TO
ADVISORY-WARNING LEVEL WIND CHILLS SATURDAY NIGHT.
SATURDAY: CORE OF H5 LOW ALOFT SINKS FROM JAMES BAY AT DAYBREAK
SOUTH AND EAST INTO NORTHERN NEW ENGLAND TOWARDS EVENING WITH T8S
NEARING -30C OVER MY WESTERN ZONES BY 00Z/SUN. COL REGION BETWEEN
LOW LEVEL REFLECTION OF THIS H5 LOW AND THE DEVELOPING SYSTEM WELL
SOUTH AND EAST OF THE BENCHMARK APPEARS TO BE ALLOWING ALL THE
INGREDIENTS FOR A BONA-FIDE NORLUN EVENT TO BE PRESENT AS THE H8
FLOW GOES SLACK ALONG WITH A DEVELOPING LLEVEL CONVERGENCE ZONE.
THERE WILL BE AMPLE INSTABILITY IN THE LLEVELS WITH WATER SURFACE TO
H8 DELTA TS NEAR -15 AND DELTA TS TO H7 NEARING -30C. THIS ALLOWS
FOR A TREMENDOUS AMOUNT OF LLEVEL INSTABILITY...WITH OCEAN-INDUCED
CAPE VALUES OF 500-1000 J/KG PORTRAYED ON THE 12Z NAM AND GFS.
THIS COULD VERY WELL PROMOTE THUNDER WITH ANY SNOW BAND THAT DOES
DEVELOP.
SNOW RATIOS: THE DENDRITIC GROWTH ZONE WILL BE BELOW THE PRIMARY
AREA OF LIFT DURING THE HEIGHT OF THE EVENT...BUT IT WILL STILL GET
CLIPPED AND SEE NO REASON WHY WE CAN/T FORCE 15-20:1 RATIOS OUT OF
THIS SETUP.
THERE IS UNCANNY AGREEMENT IN THE 12Z SUITE /NAM-GFS-ECMWF-GEM/ ON
THE PLACEMENT OF THE MESOSCALE BAND OVER PENOBSCOT BAY. WHILE THIS
WOULD TEND TO SUGGEST ABOVE NORMAL CONFIDENCE...THE FACT THAT THIS
IS A NORLUN EVENT BEGS CAUTION. A LOOK A THE 00Z NCAR ENSEMBLE
SHOWS ABOUT 40% OF THE MEMBERS DIRECTLY IMPACTING OUR AREA. WOULD
REALLY LIKE TO SEE THIS EVENT COME INTO THE NEAR TERM-HIGH
RESOLUTION GUIDANCE WINDOW AND AS SUCH...WITH THE WORD OUT RIGHT NOW
WITH THE WATCH...WILL LET THE EVENING SHIFT TAKE A FINAL LOOK AT
THINGS BEFORE MAKING A FINAL DECISION ON WINTER STORM WARNINGS VS.
WINTER WEATHER ADVISORIES. THAT BEING SAID...CERTAINLY CANNOT RULE
OUT SOME 1 FOOT+ SNOWFALL AMOUNTS SOMEWHERE IN THE MID COAST REGION
GIVEN THE SETUP ABOVE.
TEMPERATURES: MAY RISE SLIGHTLY IN THE EARLY MORNING...BUT WILL
THEN REVERSE COURSE AND FALL THROUGH THE AFTERNOON WITH ALL
LOCATIONS IN THE SINGLE DIGITS ABOVE AND BELOW ZERO BY EVENING. WIND
CHILLS WILL REACH ADVISORY LEVELS IN THE MOUNTAINS IN THE
AFTERNOON...WITH THE MOST DANGEROUS VALUES HOLDING OFF UNTIL
SATURDAY NIGHT. NONETHELESS...WIND CHILLS WILL BECOME
INCREASINGLY DANGEROUS BY LATE AFTERNOON/EVENING.
WINDS: VERY IMPRESSIVE COLD AIR ADVECTION WILL YIELD STEEP LLEVEL
LAPSE RATES...WHICH SHOULD BE ABLE TO MIX ANYTHING THE ATMOSPHERE
HAS TO OFFER WIND-WISE IN THE LOWEST 5KFT. HIGHEST WINDS IN THE
COLUMN ARE AROUND 30KTS /A BIT HIGHER OFFSHORE/ SO WILL PAINT GUSTS
AROUND 30MPH INLAND /HIGHER ON THE HILLTOPS/ AND 30-40MPH ALONG THE
COAST. NOTE: WINDS WILL NOT BE THIS STRONG IN THE VICINITY OF THE
NORLUN TROUGH AND THUS SIGNIFICANT BLOWING/DRIFTING WILL NOT
INITIALLY BE A PROBLEM. HOWEVER...BY SATURDAY EVENING...THERE
WILL LIKELY BE SIGNIFICANT BLOWING/DRIFTING...AND WILL HAVE TO
WATCH FOR THIS IF THE SNOW DOES MATERIALIZE.
SATURDAY NIGHT: H5 LOW OPENS UP AND SHIFTS EAST WITH THE CORE OF THE
COLDEST AIR ALOFT OVERHEAD UNDER CONTINUED STRONG NORTHWEST WINDS AS
GRADIENT BETWEEN 1035 MB HIGH OVER THE GREAT LAKES COMBINES WITH
OFFSHORE-MOVING NORLUN TO CONTINUE WINDS OF 15G25KTS. CONCERNS WILL
TURN TO DANGEROUSLY COLD WIND CHILLS...WHICH SHOULD HAVE NO PROBLEM
HITTING WARNING CRITERIA IN THE MOUNTAINS AND FOOTHILLS...BUT LIKELY
REMAIN AT ADVISORY LEVELS ALONG THE COAST. AM HONESTLY A BIT
SURPRISED IN THE MET/MAV LOW TEMPERATURE SPREAD AS WE SHOULD
REMAIN WELL-MIXED THROUGH THE NIGHT. DID GIVE SOME NOD TO THE
COLDER MET...WITH LOWS BELOW ZERO IN ALL LOCATIONS...AND PERHAPS
AS LOW AS -20 IN THE MOUNTAINS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH IMPACT WEATHER: DANGEROUSLY COLD WIND CHILLS LINGER INTO AT
LEAST SUNDAY MORNING. A STORM COULD BRING SNOW/FREEZING RAIN/RAIN
TO THE REGION MONDAY NIGHT INTO TUESDAY NIGHT. STRONG WINDS ARE
POSSIBLE WITH THIS SYSTEM AS WELL.
DEEP PERSISTENT 500 TROUGH OVER THE ERN CONUS ON SUNDAY WILL SHIFT
NE AND WEAKEN BY EARLY NEXT WEEK...AND THIS ALLOWS THE HEMISPHERIC
WAVE PATTERN TO BECOME LESS AMPLIFIED WITH A HIGHER WAVE NUMBER.
THE OVERALL +PNA PATTERN WEAKENS EARLY TO MID-WEEK...AND TRIES TO
BREAK DOWN BY THE END OF THE WEEK. OF NOTE THOUGH...IS SRN STREAM
WAVE THAT DIGS OVER S CENTRAL CONUS MON AND LIFTS NWD TUE AND WED
AS NRN STREAM DIVES INTO IT AND THIS COULD PRODUCE THE HIGH IMPACT
STORM OVER NEW ENGLAND AROUND TUESDAY.
SUNDAY START IN THE THROES OF THE THE VERY COLD AIR MASS IN THE
REGION WITH STRONG PRES GRAD IN PLACE AND GUSTY NW WINDS. THE
DANGEROUS WIND CHILLS LINGER THRU THE MORNING BUT AS TEMPS WARM
FROM LOWS BELOW ZERO EVERYWHERE...AND WITH PRES GRADIENT
SLACKENING AS SFC HIGH BUILDS IN SHOULD SEE WIND CHILLS RISE TO
MORE BEARABLE LVLS BY AFTERNOON. STILL...THE TAIL OF THE CAA WILL
HOLD THRU MOST OF THE DAY AND HIGHS WILL STRUGGLE TO REACH ZERO IN
THE N...AND TO REACH 10F IN THE SOUTH. AS THE SFC HIGH MOVES OVER
THE REGION LOOK FOR DECOUPLING IN MOST PLACES AND VERY GIVEN GOOD RAD
COOLING GIVEN COLD AIR IN PLACE AND A STARTING POINT NEAR OR BELOW
ZERO. WENT BELOW SUPERBLEND FOR MINS IN MOST PLACES...AND
SIGNIFICANTLY BELOW IN THE MORE SHELTERED SPOTS. THIS SHOULD BRINGUS
LOWS 10 BELOW TO ZERO IN THE COASTAL PLAIN...WITH LOWS DROPPING
TO -20 OR LOWER IN THE SHELTERED MOUNTAIN VALLEYS.
ON MONDAY LOOK FOR WARMER AIR TO START WORKING IN...AND HIGHS
REBOUND INTO THE TEENS TO MID 20S...WITH INCREASING CLOUDS IN THE
AFTERNOON.
THE NEXT SYSTEM MOVES IN ON MON NIGHT AND TUE. SOME DIFFERENCES IN
THE MODEL AS TO HAVE FAR W THE SFC LOW TRACKS...WITH THE GFS AND
GGEM PASSING IT S-N THRU THE MIDDLE OF ME...AND THE EURO AND GEFS
MEAN BRINGING IT NWD ALONG THE NY/VT BORDER...WHICH WOULD BE THE
WARMER SOLN...AND LIKELY LEAD TO SNOW TO FZRA/PL TO RAIN SOLN IN
MANY SPOTS. THE MORE EASTERLY TRACK WOULD SEE SNOW LAST LONGER
INTO THE STORM AWAY FROM THE COAST. P-TYPE WILL BE ONE OF THE BIG
ISSUES WITH THIS SYSTEM AND CONFIDENCE IS LOW AS TO HOW IT WILL
ALL UNFOLD. ONE THING TO NOTE IS THAT WE ARE COMING OUT OF VERY
COLD AIRMASS...AND DESPITE THE BEST WINDS ABOVE THE INVERSION IT
WILL BE SLOW TO BREAK OUT OF THAT LOW LVL COLD AIR...WHICH WILL
PROBABLY HOLD ON LONGER THAN THE MODELS SUGGEST. ANOTHER ISSUE
COULD BE STRONG WINDS...ALTHOUGH WITH THE INVERSION MAY BE TOUGH
FOR THOSE WINDS TO MIX TO THE SFC...AT LEAST FOR ANY SIGNIFICANT
LENGTH OF TIME.
THE WHOLE SYSTEM WILL MOVE OUT LATE TUE NIGHT AND WED. COULD BUST
OUT INTO WARMER AIR ON WED BEHIND THE SYSTEM WITH HIGHS CLIMBING
INTO THE UPPER 30S TO LOW 40S. COLD FRONT SWINGS THRU WED NIGHT
WITH UPPER LVL TROUGH ON THU AND TEMPS DROP BACK AGAIN...BELOW
NORMAL...BUT NOT TOO FAR...WITH HIGHS IN THE 20S TO AROUND 30.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...VFR UNDER MOSTLY CLEAR CONDITIONS ATTM. EXPECT
DETERIORATING CONDITIONS THROUGH THE COMING TAF PERIOD WITH SNOW
DEVELOPING OVERNIGHT AT RKD AND LIKELY AUG WITH IFR/LIFR
RESTRICTIONS. FOR A PERIOD SATURDAY...INCH PER HOUR SNOWFALL RATES
ARE POSSIBLE...MOST LIKELY AT RKD. FURTHER WEST...ARCTIC FRONT
WILL BRING A ROUND OF SNOW SHOWERS...MOST LIKELY TO BRING
RESTRICTIONS TO LEB/HIE...BUT BRIEF RESTRICTIONS ARE POSSIBLE
SOUTH AND EAST OF THIS AS WELL. CONDITIONS IMPROVE SATURDAY NIGHT
WITH VFR CONDITIONS RETURNING FOR SUNDAY.
AFTER LIGHT WINDS OVERNIGHT...STRONG NORTHWEST WINDS /15G25KTS/
WILL DEVELOP BY LATE MORNING SATURDAY AND CONTINUE THROUGH
SATURDAY NIGHT.
LONG TERM...MAINLY VFR SUN THRU MON WITH GUSTY NW WINDS
DIMINISHING DURING SUN AFTERNOON. COULD SEE EXTENDED PERIOD OF
IFR OR LOWER IN SN/FZRA/RA MON NIGHT INTO TUE NIGHT.
&&
.MARINE...
SHORT TERM...WINDS/WAVES BELOW SMALL CRAFT LEVELS INTO TOMORROW
MORNING BEFORE INTENSE COLD ADVECTION BEHIND AN ARCTIC COLD FRONT
BRINGS A PERIOD OF GALES TO THE OUTER WATERS BY LATE SATURDAY
AFTERNOON THROUGH SUNDAY MORNING WITH WINDS LIKELY REMAINING BELOW
GALE FORCE IN THE BAYS. IN ADDITION...HEAVY FREEZING SPRAY
WARNINGS HAVE BEEN HOISTED SATURDAY EVENING THROUGH SUNDAY MORNING
GIVEN THE COMBINATION OF THE AFOREMENTIONED WINDS AND THE COLDEST
AIRMASS OF THE SEASON THUS FAR.
LONG TERM...NW WIND DIMINISH SLOWLY THRU SUNDAY...AS DOES
INTENSITY OF FREEZING SPRAY...BUT WILL LKLY HOLD TO SCA WINDS
THRU SUN EVE. AFTER A BRIEF BREAK IN THE WINDS ON MON AND MON
NIGHT...LOOK FOR S WINDS TO REACH SCA LVLS EARLY TUE AND COULD
REACH GALES BY TUE AFTERNOON AND EVE...BEFORE DIMINISHING WED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WIND CHILL WARNING FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR MEZ012>014-018>022.
WIND CHILL WARNING FROM 7 PM SATURDAY TO 10 AM EST SUNDAY FOR
MEZ007>009.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST SATURDAY NIGHT FOR
MEZ022-026.
WIND CHILL ADVISORY FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR MEZ023>028.
WINTER STORM WARNING UNTIL MIDNIGHT EST SATURDAY NIGHT FOR
MEZ027-028.
NH...WIND CHILL WARNING FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR NHZ004>013-015.
WIND CHILL WARNING FROM 7 PM SATURDAY TO 10 AM EST SUNDAY FOR
NHZ001>003.
WIND CHILL ADVISORY FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR NHZ014.
MARINE...HEAVY FREEZING SPRAY WARNING FROM 7 PM SATURDAY TO NOON EST
SUNDAY FOR ANZ150>154.
SMALL CRAFT ADVISORY FROM NOON SATURDAY TO NOON EST SUNDAY FOR
ANZ151-153.
GALE WARNING FROM 4 PM SATURDAY TO NOON EST SUNDAY FOR ANZ150-
152-154.
&&
$$
NEAR TERM UPDATE...EKSTER
SHORT TERM...ARNOTT
LONG TERM...CEMPA
AVIATION...ARNOTT/CEMPA
MARINE...ARNOTT/CEMPA
AREA FORECAST DISCUSSION
NWS GRAY ME
645 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL CROSS THE REGION TONIGHT THROUGH SATURDAY
USHERING IN THE COLDEST AIRMASS OF THE SEASON THUS FAR. AS THIS
COLD AIR INTERACTS WITH A TROUGH OF LOW PRESSURE OVER THE GULF OF
MAINE...A PERIOD OF MODERATE TO HEAVY SNOW WILL BE POSSIBLE ALONG
THE MIDCOAST REGION OF MAINE. BEYOND THIS...THE COMBINATION OF COLD
TEMPERATURES AND STRONG NORTHWEST WINDS WILL CAUSE DANGEROUSLY COLD
WIND CHILLS SATURDAY NIGHT AND SUNDAY. TEMPERATURES WILL RAPIDLY
MODERATE NEXT WEEK WITH A WINTRY MIX OF PRECIPITATION POTENTIALLY
TRANSITIONING TO RAIN ON MONDAY NIGHT AND TUESDAY ALONG WITH STRONG
SOUTHERLY WINDS.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
635 PM UPDATE...HAVE CONTINUED TO POUR OVER LATEST OBERVATIONAL
AND MESOSCALE MODEL DATA EARLY THIS EVENING TO TRY AND PIN DOWN
THE FORMATION AND MOVEMENT OF AN INVERTED TROF THAT MAY BRING
HEAVY SNOWFALL TO A PORTION OF THE MID COAST. UNFORTUNATELY AT
THIS TIME IT IS A LITTLE TO EARLY TO SEE ANYTHING SIGNIFICANT IN
THE LATEST OBSERVATIONAL DATA SUCH AS BUOYS AND RADAR. AS FAR AS
THE MESOSCALE MODELS GO...THERE IS STILL A LOT OF SPREAD IN WHERE
THIS BAND WILL /OR WILL NOT/ DEVELOP OVER LAND. THE LATEST RUNS OF
THE NAM AND RGEM AS WELL AS THE 2.5 KM CANADIAN HIT KNOX AND
WALDO COUNTIES PRETTY HARD. HOWEVER...THE LATEST RUNS OF THE HRRR
AND RAP KEEP MUCH OF THE ACCUMULATING SNOWFALL OFFSHORE EXCEPT
PERHAPS THE PENINSULAS AND ISLANDS OF THE MID COAST. WITH SO MUCH
UNCERTAINTY REMAINING AND NO SIGN OF DEVELOPMENT YET IN
OBSERVATIONAL DATA...CAN/T REALLY JUSTIFY A WINTER STORM WARNING.
WILL HOLD ONTO THE WATCH FOR A FEW MORE HOURS. WILL LIKELY MAKE A
DECISION BY 10 PM...AND IF THERE IS STILL A LOT OF UNCERAINTY BY
THEN WE MAY JUST GO WITH AN ADVISORY AND LET THE NEXT SHIFT
UPGRADE TO A WARNING IF NEED BE.
PREVIOUSLY...
HIGH IMPACT WEATHER POTENTIAL: SNOW DEVELOPS ALONG THE MIDCOAST
OVERNIGHT. CURRENT PATTERN: EARLY AFTERNOON WATER VAPOR IMAGERY
REVEALS RIDGE- TROUGH PATTERN ACROSS THE CONUS...WITH IMPRESSIVE
PORTION OF THE POLAR VORTEX CURRENTLY CENTERED OVER JAMES BAY.
SOUTH OF THIS FEATURE...WATER VAPOR IMAGERY DEFINES A DIGGING
SHORTWAVE /DARKENING OF THE IMAGERY/ OVER THE NORTHERN OHIO
VALLEY. THIS WILL HELP FORCE CYCLOGENESIS OFF THE MID ATLANTIC
COAST THAT WILL RACE NORTHEAST WELL SOUTH AND EAST OF NEW ENGLAND
THROUGH SATURDAY. A WEAKER SURFACE LOW IS CURRENTLY DEPICTED OVER
THE EASTERN GREAT LAKES ASSOCIATED WITH FORCING AHEAD OF THE H5
LOW OVER JAMES BAY. AS THIS LATTER FEATURE DIVES SOUTH AND EAST
TOWARDS NEW ENGLAND THIS WEEKEND...THE ASSOCIATED SURFACE LOW WILL
BE ABSORBED INTO THE DEVELOPING SYSTEM OFFSHORE. OUR PRIMARY
WEATHER IMPACTS WILL BE 1- WHAT HAPPENS BETWEEN THESE SYSTEMS AS
IMPRESSIVE MID AND UPPER LEVEL FORCING COMBINES WITH VERY
SUBSTANTIAL INSTABILITY OVER THE RELATIVELY WARM GULF OF MAINE
WATERS AND 2- THE RAMIFICATIONS OF ARRIVING ARCTIC AIR. TEMPS AT
H8 THIS MORNING WERE -35C OVER JAMES BAY WITH TEMPERATURES CLOSE
TO THIS REACHING NEW ENGLAND ON SATURDAY...PRESENTING WIND CHILL
CONCERNS AS IMPRESSIVE COLD ADVECTION DRIVES THIS AIR INTO THE
REGION.
TONIGHT: EXPECT A GENERAL INCREASE IN MID AND UPPER LEVEL
CLOUDINESS PER A LOOK AT AFTERNOON VISIBLE SATELLITE IMAGERY AS
WEAK WARM ADVECTION CONTINUES AHEAD OF APPROACHING SURFACE LOW NOW
NORTH OF LAKE ONTARIO. FORCING FOR ASCENT WILL BE ON THE INCREASE
WITH TOP DOWN SATURATION LIKELY BRINGING SNOW SHOWER ACTIVITY INTO
THE MOUNTAINS OVERNIGHT. WE/LL TALK MORE ABOUT THE NORLUN EVENT IN
THE SHORT TERM SECTION BELOW...BUT EXPERIMENTAL HRRR IS ON BOARD
WITH THE 12Z GUIDANCE SUITE IN DEVELOPING LLEVEL CONVERGENCE IN THE
VICINITY OF PENOBSCOT BAY BY MIDNIGHT TONIGHT...WITH SNOW DEVELOPING
IN THIS REGION AND CONTINUING THROUGH THE MORNING. WITH A GOOD
FLUFF FACTOR HELPING ACCUMULATIONS...COULD SEE 1-3 INCHES OVER
KNOX/WALDO COUNTIES BY DAYBREAK.
TEMPERATURES: WITH SOUTHWEST FLOW ONGOING AND CLOUDS ON THE
INCREASE...TEMPERATURES WILL BE A GOOD BIT WARMER THAN THE PREVIOUS
NIGHT BUT GIVEN THE CHILLY HIGHS OF TODAY...WILL CERTAINLY NOT BE
WARM. EXPECT LOWS IN THE SINGLE DIGITS IN THE MOUNTAINS THROUGH THE
LOWER TEENS ALONG THE COAST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
SIGNIFICANT SNOW ALONG THE MID COAST BECOMING INCREASINGLY
LIKELY SATURDAY...
DANGEROUSLY COLD WIND CHILLS SATURDAY NIGHT THROUGHOUT THE
REGION...
HIGH IMPACT WEATHER POTENTIAL: HEAVY SNOW TOTALS POSSIBLE IN THE
VICINITY OF PENOBSCOT BAY SATURDAY WITH ATTENTION THEN TURNING TO
ADVISORY-WARNING LEVEL WIND CHILLS SATURDAY NIGHT.
SATURDAY: CORE OF H5 LOW ALOFT SINKS FROM JAMES BAY AT DAYBREAK
SOUTH AND EAST INTO NORTHERN NEW ENGLAND TOWARDS EVENING WITH T8S
NEARING -30C OVER MY WESTERN ZONES BY 00Z/SUN. COL REGION BETWEEN
LOW LEVEL REFLECTION OF THIS H5 LOW AND THE DEVELOPING SYSTEM WELL
SOUTH AND EAST OF THE BENCHMARK APPEARS TO BE ALLOWING ALL THE
INGREDIENTS FOR A BONA-FIDE NORLUN EVENT TO BE PRESENT AS THE H8
FLOW GOES SLACK ALONG WITH A DEVELOPING LLEVEL CONVERGENCE ZONE.
THERE WILL BE AMPLE INSTABILITY IN THE LLEVELS WITH WATER SURFACE TO
H8 DELTA TS NEAR -15 AND DELTA TS TO H7 NEARING -30C. THIS ALLOWS
FOR A TREMENDOUS AMOUNT OF LLEVEL INSTABILITY...WITH OCEAN-INDUCED
CAPE VALUES OF 500-1000 J/KG PORTRAYED ON THE 12Z NAM AND GFS.
THIS COULD VERY WELL PROMOTE THUNDER WITH ANY SNOW BAND THAT DOES
DEVELOP.
SNOW RATIOS: THE DENDRITIC GROWTH ZONE WILL BE BELOW THE PRIMARY
AREA OF LIFT DURING THE HEIGHT OF THE EVENT...BUT IT WILL STILL GET
CLIPPED AND SEE NO REASON WHY WE CAN/T FORCE 15-20:1 RATIOS OUT OF
THIS SETUP.
THERE IS UNCANNY AGREEMENT IN THE 12Z SUITE /NAM-GFS-ECMWF-GEM/ ON
THE PLACEMENT OF THE MESOSCALE BAND OVER PENOBSCOT BAY. WHILE THIS
WOULD TEND TO SUGGEST ABOVE NORMAL CONFIDENCE...THE FACT THAT THIS
IS A NORLUN EVENT BEGS CAUTION. A LOOK A THE 00Z NCAR ENSEMBLE
SHOWS ABOUT 40% OF THE MEMBERS DIRECTLY IMPACTING OUR AREA. WOULD
REALLY LIKE TO SEE THIS EVENT COME INTO THE NEAR TERM-HIGH
RESOLUTION GUIDANCE WINDOW AND AS SUCH...WITH THE WORD OUT RIGHT NOW
WITH THE WATCH...WILL LET THE EVENING SHIFT TAKE A FINAL LOOK AT
THINGS BEFORE MAKING A FINAL DECISION ON WINTER STORM WARNINGS VS.
WINTER WEATHER ADVISORIES. THAT BEING SAID...CERTAINLY CANNOT RULE
OUT SOME 1 FOOT+ SNOWFALL AMOUNTS SOMEWHERE IN THE MID COAST REGION
GIVEN THE SETUP ABOVE.
TEMPERATURES: MAY RISE SLIGHTLY IN THE EARLY MORNING...BUT WILL
THEN REVERSE COURSE AND FALL THROUGH THE AFTERNOON WITH ALL
LOCATIONS IN THE SINGLE DIGITS ABOVE AND BELOW ZERO BY EVENING. WIND
CHILLS WILL REACH ADVISORY LEVELS IN THE MOUNTAINS IN THE
AFTERNOON...WITH THE MOST DANGEROUS VALUES HOLDING OFF UNTIL
SATURDAY NIGHT. NONETHELESS...WIND CHILLS WILL BECOME
INCREASINGLY DANGEROUS BY LATE AFTERNOON/EVENING.
WINDS: VERY IMPRESSIVE COLD AIR ADVECTION WILL YIELD STEEP LLEVEL
LAPSE RATES...WHICH SHOULD BE ABLE TO MIX ANYTHING THE ATMOSPHERE
HAS TO OFFER WIND-WISE IN THE LOWEST 5KFT. HIGHEST WINDS IN THE
COLUMN ARE AROUND 30KTS /A BIT HIGHER OFFSHORE/ SO WILL PAINT GUSTS
AROUND 30MPH INLAND /HIGHER ON THE HILLTOPS/ AND 30-40MPH ALONG THE
COAST. NOTE: WINDS WILL NOT BE THIS STRONG IN THE VICINITY OF THE
NORLUN TROUGH AND THUS SIGNIFICANT BLOWING/DRIFTING WILL NOT
INITIALLY BE A PROBLEM. HOWEVER...BY SATURDAY EVENING...THERE
WILL LIKELY BE SIGNIFICANT BLOWING/DRIFTING...AND WILL HAVE TO
WATCH FOR THIS IF THE SNOW DOES MATERIALIZE.
SATURDAY NIGHT: H5 LOW OPENS UP AND SHIFTS EAST WITH THE CORE OF THE
COLDEST AIR ALOFT OVERHEAD UNDER CONTINUED STRONG NORTHWEST WINDS AS
GRADIENT BETWEEN 1035 MB HIGH OVER THE GREAT LAKES COMBINES WITH
OFFSHORE-MOVING NORLUN TO CONTINUE WINDS OF 15G25KTS. CONCERNS WILL
TURN TO DANGEROUSLY COLD WIND CHILLS...WHICH SHOULD HAVE NO PROBLEM
HITTING WARNING CRITERIA IN THE MOUNTAINS AND FOOTHILLS...BUT LIKELY
REMAIN AT ADVISORY LEVELS ALONG THE COAST. AM HONESTLY A BIT
SURPRISED IN THE MET/MAV LOW TEMPERATURE SPREAD AS WE SHOULD
REMAIN WELL-MIXED THROUGH THE NIGHT. DID GIVE SOME NOD TO THE
COLDER MET...WITH LOWS BELOW ZERO IN ALL LOCATIONS...AND PERHAPS
AS LOW AS -20 IN THE MOUNTAINS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH IMPACT WEATHER: DANGEROUSLY COLD WIND CHILLS LINGER INTO AT
LEAST SUNDAY MORNING. A STORM COULD BRING SNOW/FREEZING RAIN/RAIN
TO THE REGION MONDAY NIGHT INTO TUESDAY NIGHT. STRONG WINDS ARE
POSSIBLE WITH THIS SYSTEM AS WELL.
DEEP PERSISTENT 500 TROUGH OVER THE ERN CONUS ON SUNDAY WILL SHIFT
NE AND WEAKEN BY EARLY NEXT WEEK...AND THIS ALLOWS THE HEMISPHERIC
WAVE PATTERN TO BECOME LESS AMPLIFIED WITH A HIGHER WAVE NUMBER.
THE OVERALL +PNA PATTERN WEAKENS EARLY TO MID-WEEK...AND TRIES TO
BREAK DOWN BY THE END OF THE WEEK. OF NOTE THOUGH...IS SRN STREAM
WAVE THAT DIGS OVER S CENTRAL CONUS MON AND LIFTS NWD TUE AND WED
AS NRN STREAM DIVES INTO IT AND THIS COULD PRODUCE THE HIGH IMPACT
STORM OVER NEW ENGLAND AROUND TUESDAY.
SUNDAY START IN THE THROES OF THE THE VERY COLD AIR MASS IN THE
REGION WITH STRONG PRES GRAD IN PLACE AND GUSTY NW WINDS. THE
DANGEROUS WIND CHILLS LINGER THRU THE MORNING BUT AS TEMPS WARM
FROM LOWS BELOW ZERO EVERYWHERE...AND WITH PRES GRADIENT
SLACKENING AS SFC HIGH BUILDS IN SHOULD SEE WIND CHILLS RISE TO
MORE BEARABLE LVLS BY AFTERNOON. STILL...THE TAIL OF THE CAA WILL
HOLD THRU MOST OF THE DAY AND HIGHS WILL STRUGGLE TO REACH ZERO IN
THE N...AND TO REACH 10F IN THE SOUTH. AS THE SFC HIGH MOVES OVER
THE REGION LOOK FOR DECOUPLING IN MOST PLACES AND VERY GIVEN GOOD RAD
COOLING GIVEN COLD AIR IN PLACE AND A STARTING POINT NEAR OR BELOW
ZERO. WENT BELOW SUPERBLEND FOR MINS IN MOST PLACES...AND
SIGNIFICANTLY BELOW IN THE MORE SHELTERED SPOTS. THIS SHOULD BRINGUS
LOWS 10 BELOW TO ZERO IN THE COASTAL PLAIN...WITH LOWS DROPPING
TO -20 OR LOWER IN THE SHELTERED MOUNTAIN VALLEYS.
ON MONDAY LOOK FOR WARMER AIR TO START WORKING IN...AND HIGHS
REBOUND INTO THE TEENS TO MID 20S...WITH INCREASING CLOUDS IN THE
AFTERNOON.
THE NEXT SYSTEM MOVES IN ON MON NIGHT AND TUE. SOME DIFFERENCES IN
THE MODEL AS TO HAVE FAR W THE SFC LOW TRACKS...WITH THE GFS AND
GGEM PASSING IT S-N THRU THE MIDDLE OF ME...AND THE EURO AND GEFS
MEAN BRINGING IT NWD ALONG THE NY/VT BORDER...WHICH WOULD BE THE
WARMER SOLN...AND LIKELY LEAD TO SNOW TO FZRA/PL TO RAIN SOLN IN
MANY SPOTS. THE MORE EASTERLY TRACK WOULD SEE SNOW LAST LONGER
INTO THE STORM AWAY FROM THE COAST. P-TYPE WILL BE ONE OF THE BIG
ISSUES WITH THIS SYSTEM AND CONFIDENCE IS LOW AS TO HOW IT WILL
ALL UNFOLD. ONE THING TO NOTE IS THAT WE ARE COMING OUT OF VERY
COLD AIRMASS...AND DESPITE THE BEST WINDS ABOVE THE INVERSION IT
WILL BE SLOW TO BREAK OUT OF THAT LOW LVL COLD AIR...WHICH WILL
PROBABLY HOLD ON LONGER THAN THE MODELS SUGGEST. ANOTHER ISSUE
COULD BE STRONG WINDS...ALTHOUGH WITH THE INVERSION MAY BE TOUGH
FOR THOSE WINDS TO MIX TO THE SFC...AT LEAST FOR ANY SIGNIFICANT
LENGTH OF TIME.
THE WHOLE SYSTEM WILL MOVE OUT LATE TUE NIGHT AND WED. COULD BUST
OUT INTO WARMER AIR ON WED BEHIND THE SYSTEM WITH HIGHS CLIMBING
INTO THE UPPER 30S TO LOW 40S. COLD FRONT SWINGS THRU WED NIGHT
WITH UPPER LVL TROUGH ON THU AND TEMPS DROP BACK AGAIN...BELOW
NORMAL...BUT NOT TOO FAR...WITH HIGHS IN THE 20S TO AROUND 30.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM...VFR UNDER MOSTLY CLEAR CONDITIONS ATTM. EXPECT
DETERIORATING CONDITIONS THROUGH THE COMING TAF PERIOD WITH SNOW
DEVELOPING OVERNIGHT AT RKD AND LIKELY AUG WITH IFR/LIFR
RESTRICTIONS. FOR A PERIOD SATURDAY...INCH PER HOUR SNOWFALL RATES
ARE POSSIBLE...MOST LIKELY AT RKD. FURTHER WEST...ARCTIC FRONT
WILL BRING A ROUND OF SNOW SHOWERS...MOST LIKELY TO BRING
RESTRICTIONS TO LEB/HIE...BUT BRIEF RESTRICTIONS ARE POSSIBLE
SOUTH AND EAST OF THIS AS WELL. CONDITIONS IMPROVE SATURDAY NIGHT
WITH VFR CONDITIONS RETURNING FOR SUNDAY.
AFTER LIGHT WINDS OVERNIGHT...STRONG NORTHWEST WINDS /15G25KTS/
WILL DEVELOP BY LATE MORNING SATURDAY AND CONTINUE THROUGH
SATURDAY NIGHT.
LONG TERM...MAINLY VFR SUN THRU MON WITH GUSTY NW WINDS
DIMINISHING DURING SUN AFTERNOON. COULD SEE EXTENDED PERIOD OF
IFR OR LOWER IN SN/FZRA/RA MON NIGHT INTO TUE NIGHT.
&&
.MARINE...
SHORT TERM...WINDS/WAVES BELOW SMALL CRAFT LEVELS INTO TOMORROW
MORNING BEFORE INTENSE COLD ADVECTION BEHIND AN ARCTIC COLD FRONT
BRINGS A PERIOD OF GALES TO THE OUTER WATERS BY LATE SATURDAY
AFTERNOON THROUGH SUNDAY MORNING WITH WINDS LIKELY REMAINING BELOW
GALE FORCE IN THE BAYS. IN ADDITION...HEAVY FREEZING SPRAY
WARNINGS HAVE BEEN HOISTED SATURDAY EVENING THROUGH SUNDAY MORNING
GIVEN THE COMBINATION OF THE AFOREMENTIONED WINDS AND THE COLDEST
AIRMASS OF THE SEASON THUS FAR.
LONG TERM...NW WIND DIMINISH SLOWLY THRU SUNDAY...AS DOES
INTENSITY OF FREEZING SPRAY...BUT WILL LKLY HOLD TO SCA WINDS
THRU SUN EVE. AFTER A BRIEF BREAK IN THE WINDS ON MON AND MON
NIGHT...LOOK FOR S WINDS TO REACH SCA LVLS EARLY TUE AND COULD
REACH GALES BY TUE AFTERNOON AND EVE...BEFORE DIMINISHING WED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WIND CHILL WARNING FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR MEZ012>014-018>022.
WIND CHILL WARNING FROM 7 PM SATURDAY TO 10 AM EST SUNDAY FOR
MEZ007>009.
WIND CHILL ADVISORY FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR MEZ023>028.
WINTER STORM WATCH FROM MIDNIGHT EST TONIGHT THROUGH SATURDAY
EVENING FOR MEZ022-027-028.
NH...WIND CHILL WARNING FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR NHZ004>013-015.
WIND CHILL WARNING FROM 7 PM SATURDAY TO 10 AM EST SUNDAY FOR
NHZ001>003.
WIND CHILL ADVISORY FROM MIDNIGHT SATURDAY NIGHT TO 10 AM EST
SUNDAY FOR NHZ014.
MARINE...HEAVY FREEZING SPRAY WARNING FROM 7 PM SATURDAY TO NOON EST
SUNDAY FOR ANZ150>154.
SMALL CRAFT ADVISORY FROM NOON SATURDAY TO NOON EST SUNDAY FOR
ANZ151-153.
GALE WARNING FROM 4 PM SATURDAY TO NOON EST SUNDAY FOR ANZ150-
152-154.
&&
$$
NEAR TERM UPDATE...EKSTER
SHORT TERM...ARNOTT
LONG TERM...CEMPA
AVIATION...ARNOTT/CEMPA
MARINE...ARNOTT/CEMPA
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
632 PM EST FRI FEB 12 2016
.SYNOPSIS...
AN ARCTIC FRONT WILL BRING SNOW SHOWERS TO THE AREA THROUGH
SATURDAY. MUCH COLDER TEMPERATURES AND DANGEROUS WIND CHILLS WILL
CONTINUE INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH SATURDAY/...
BASED ON LATEST OBSERVATIONS AND RADAR TRENDS CURRENT TIMING OF
POTENTIAL SQUALL CONDITIONS STILL LOOKS GOOD AS WV IMAGERY SHOWS
THE JET CORE ROUNDING THE BASE OF THE LONGWAVE PIVOTING OVER THE
AREA. NOT MUCH CHANGE IS NEEDED AT THIS TIME TO THE ONGOING
FORECAST OTHER THAN MINOR ADJUSTMENTS TO HOURLY TEMPERATURES.
PREV DISCUSSION FOLLOWS..
SHORTWAVE PIVOTING ALONG THE BASE OF THE UPPER TROUGH WILL SUPPORT
INCREASING SNOW CHANCES IN THE RIDGES AHEAD OF THE ARCTIC FRONT
PASSAGE PROGGED FOR THIS EVENING/OVERNIGHT. BOTH HI RES AND LONGER
RANGE MODEL SOUNDINGS IN BUFKIT SUGGEST A PERIOD WHERE DEEP
MOISTURE...IN A LAYER FROM ABOUT 600MB TO 850MB...WILL BE WELL
WITHIN THE DENDRITIC GROWTH ZONE. THIS SHOULD SUPPORT EFFICIENT
SNOWFALL FOR A PERIOD...WITH ADDITIONAL SNOW SHOWERS ANTICIPATED
WITH AND BEHIND THE FRONT IN UPSLOPE SNOW UNTIL THE WHOLE BOUNDARY
LAYER FALLS WELL BELOW THE GROWTH ZONE. WITH THIS IN MIND...A
WINTER WEATHER ADVISORY WAS ISSUED FOR THE RIDGES OF PRESTON
TUCKER AND GARRETT COUNTIES THROUGH SATURDAY MORNING.
ELSEWHERE...THE MODEL GUIDANCE HAS CHANGED LITTLE WITH THE TIMING
OF THE SNOW SHOWERS AND POTENTIAL SQUALLS AHEAD OF THE FRONT
PROGGED FOR PASSAGE OVERNIGHT. EXPECT THE LINE TO BE INTO EASTERN
OHIO AND NORTHWESTERN PA BY 00Z AND PITTSBURGH BY 03Z. VARIOUS
RUNS OF THE HRRR AND TO A LESSER DEGREE OTHER SNOW SQUALLS PROGS
SUGGEST THAT THERE WILL BE SOME WEAKENING AS THE LINE COMES
ACROSS. GENERALLY ANTICIPATE A HALF TO AN INCH OF SNOW...WITH
SLIGHTLY HIGHER AMOUNTS NORTH OF PITTSBURGH.
BEHIND THE FRONT...STRONG COLD ADVECTION WILL STEEPEN LAPSE RATES
AND PROVIDE FOR A PERIOD OF GUSTY WINDS AREAWIDE UNTIL LATE
SATURDAY WITH MAXIMUM WIND IN THE BOUNDARY LAYER APPROACHING 25
TO 35KTS. THIS...ADDED TO TEMPERATURES FALLING INTO THE SINGLE
DIGITS WILL LEAD TO WIND CHILL VALUES WELL BELOW ZERO. THIS
SUPPORTS THE WIND CHILL ADVISORY THAT WAS ISSUED. 40MPH WIND
GUSTS OVERNIGHT IN THE RIDGES WILL ALLOW VALUES TO GET VERY CLOSE
TO WARNING CRITERIA BUT AT THIS POINT...THE WATCH HAS BEEN
UPGRADED TO AN ADVISORY WITH SOME -25 VALUES POSSIBLE IN THE
HIGHEST TERRAIN OF TUCKER COUNTY.
IN ADDITION TO THE WIND...LAKE EFFECT SNOW SHOWERS WILL BE
POSSIBLE IN NORTHWEST FLOW WITH MOST IF NOT ALL OF THE MODEL
GUIDANCE SUGGESTING SEVERAL DUAL-LAKE SNOW BANDS. THE LATEST
ITERATION OF MODELS HAS THE MORE PROMINENT BAND SHIFTED SLIGHTLY
SOUTH FROM LAST NIGHT SO WITH UNCERTAINTY IN THE ACTUAL PLACEMENT
OF SNOW BANDS...HAVE OPTED TO UPGRADE THE LAKE EFFECT SNOW WATCH
FOR VENANGO COUNTY TO AN ADVISORY FOR MERCER...VENANGO...AND
FOREST COUNTIES. ADDITIONAL LAKE PLUMES MAY SUPPORT SNOW BEYOND
THESE ADVISORIES THROUGH SATURDAY AFTERNOON...BUT WITH UNCERTAINTY
IN THEIR PLACEMENT...NO ADDITIONAL HEADLINES WERE ADDED.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO TAPER OFF AND SHIFT
NORTHWARD AS A SURFACE RIDGE ATTEMPTS TO BUILD OVERHEAD FOR
SUNDAY. THIS SHOULD ALLOW FOR THE WIND TO BACK OFF...WITH WIND
CHILL CONCERNS DIMINISHING IN OHIO. HOWEVER...WITH THE HIGH
PRESSURE AND LIGHT WIND...TEMPERATURES WILL FALL CLOSE TO OR BELOW
ZERO SATURDAY NIGHT...SO ADVISORIES WILL REMAIN AS IS FOR THE REST
OF THE CWA UNTIL SUNDAY MORNING. TEMPERATURES WILL MODERATE A FEW
DEGREES ON SUNDAY WITH A RETURN OF SOUTHERLY FLOW AND SCATTERING
OF THE CLOUDS. TEMPERATURE FORECAST WAS A BLEND OF GUIDANCE FOR
BOTH PERIODS.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
SHORTWAVE MOVING EAST ACROSS THE GREAT LAKES WILL BRING WARM
ADVECTION ALONG WITH AN INCREASE IN DEEPER MOISTURE SUNDAY NIGHT
INTO MONDAY. THIS WILL GIVE A PERIOD OF SNOW ESPECIALLY SOUTH OF
PITTSBURGH WITH SOME ACCUMULATION EXPECTED. TEMPERATURES LOOK TO
RISE LATER SUNDAY NIGHT AND WILL PUSH TO NEAR THE SEASONAL AVERAGE
MONDAY. BY LATER MONDAY THROUGH TUESDAY A STRONG SOUTHERN STREAM
SHORTWAVE WILL INDUCE LOW PRESSURE ALONG THE GULF COAST WHICH WILL
QUICKLY MOVE ACROSS THE MID ATLANTIC STATES. MODELS STILL DIFFER
ON EXACT TRACK BUT SYSTEM WILL CROSS THE SOUTHERN APPALACHIANS AND
INTENSIFY AS IT MOVES TOWARD NEW ENGLAND BY TUESDAY NIGHT.
POTENTIAL FOR SIGNIFICANT SNOW...BUT ALSO POTENTIAL FOR A MIX WITH
RAIN OR ALL RAIN WHERE BETTER QPF IS FORECAST. FOR NOW HAVE NOT
STRAYED FAR FROM PREVIOUS FORECAST ALTHOUGH EVEN THE WARMER ECMWF
WRAPS COLD AIR BACK IN LATER TUESDAY SO HAVE KEPT MAINLY SNOW.
SYSTEM EXITS TUESDAY NIGHT...BUT WILL BE FOLLOWED BY FAST MOVING
CLIPPER SYSTEM WEDNESDAY WHICH WILL DELIVER ANOTHER PERIOD OF SNOW
SHOWERS FOLLOWED BY A QUICK SHOT OF COLD AIR. HEIGHTS ALOFT THEN
BEGIN TO RISE THURSDAY INTO FRIDAY WITH STRONG WARM
ADVECTION...ESPECIALLY ON FRIDAY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
MOST IMPORTANT FEATURE THROUGH THE BEGINNING OF THE TAFS WILL BE
THE ARRIVAL OF AN ARCTIC FRONT. UPSTREAM OBSERVATIONS AT
CLEVELAND SHOW 1/4SM VISIBILITY WITH HEAVY SNOW AND NORTHWEST WIND
GUSTS TO 30KT. ALTHOUGH THE LINE OF SNOW SHOWERS ALONG THE FRONT
WILL WEAKEN SOMEWHAT AS IT MOVES INLAND OFF LAKE ERIE...STILL
THINK THAT WIDESPREAD 1/2 TO 1 MILE VISIBILITIES AND WIND GUSTS TO
25-30KT ARE POSSIBLE AT EACH TERMINAL AS THE LINE MOVES THROUGH.
THIS LINE SHOULD HAVE MOVED THROUGH ALL LOCAL TERMINALS BY
06Z.
ALTHOUGH SNOW WITH MVFR/IFR VISIBILITIES WILL CONTINUE OVERNIGHT
BEHIND THE FRONT AT MOST TERMINALS...FKL IS LIKELY TO BE THE
TERMINAL WITH THE LOWEST FLIGHT CONDITIONS DUE TO THE POTENTIAL OF
A LAKE HURON- ERIE SNOWBAND TO SET UP WITH NORTHWEST WINDS. THE
POTENTIAL FOR MODERATE SNOW WILL CONTINUE THERE THROUGH MUCH OF
SATURDAY. ZZV COULD MANAGE TO EITHER SCATTER OUT OR HAVE CEILINGS
LIFT TO VFR ON SATURDAY. WIND GUSTS TO 25 KT WILL CONTINUE BEHIND
THE FRONT AND SHOULD LAST THROUGH THE TAF PERIOD.
.OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
LOW PRESSURE SYSTEMS WILL BRING WIDESPREAD RESTRICTIONS LATER
SUNDAY NIGHT THROUGH WEDNESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR MDZ001.
WINTER WEATHER ADVISORY UNTIL 10 AM EST SATURDAY FOR MDZ001.
OH...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST
SATURDAY FOR OHZ039-048-049-057>059-068-069.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR OHZ040-041-050.
PA...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR PAZ007>009-013>016-020>023-029-031-073>076.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST SATURDAY FOR
PAZ007>009.
WV...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST
SATURDAY FOR WVZ003-004-012.
WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR WVZ001-002-021-509>514.
WINTER WEATHER ADVISORY UNTIL 10 AM EST SATURDAY FOR
WVZ512>514.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
559 PM EST THU FEB 11 2016
.SYNOPSIS...
SCATTERED SNOW SHOWERS SHOULD END TONIGHT AS HIGH PRESSURE BUILDS
IN. A COLD FRONT WILL BRING MORE SNOW CHANCES FRIDAY AND
SATURDAY...WITH MUCH COLDER TEMPERATURES FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
WITH 6PM UPDATE...TWEAKED HOURLY POPS AND TEMPERATURES...KEEPING
SCATTERED SNOW SHOWERS IN THE FORECAST SLIGHTLY LONGER FOR THE
TIER OF COUNTIES JUST NORTH OF PITTSBURGH WHERE ECHOES HAVE HELD
ON THE LONGEST. ALTHOUGH THE VERY COLD AIR IS NOT EXPECTED TO MOVE
INTO THE REGION UNTIL TOMORROW NIGHT...LATEST HRRR RUNS SUGGEST
TEMPERATURES COULD PLUMMET ALONG INTERSTATE 80 IF SKIES MANAGE TO
CLEAR OUT. THINK THE CLOUDS WILL HANG IN LONG ENOUGH TO PREVENT
THIS FROM HAPPENING...BUT WILL KEEP AN EYE ON THIS THROUGHOUT THE
NIGHT. PREVIOUS DISCUSSION FOLLOWS.
SCATTERED LAKE ENHANCED SNOW SHOULD CONTINUE TO TAPER OFF THRU THE
EVE AS MDL PROGGED AND OBSERVED UPSTREAM SOUNDINGS SHOW LWRG TEMP
INVERSIONS...AND WKNG LAPSE RATES. BLDG HIGH PRESSURE SHOULD
BRING CLRG SKIES TONIGHT. TEMPS SHOULD AVG AROUND 15 DEG BELOW
SEASONAL LVLS USING THE LATEST NR TERM CONSENSUS BLENDED
GUIDANCE.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
THE NEXT SHORTWAVE IS PROGGED TO CROSS THE LWR OH VLY/MID ATLANTIC
RGN FRI BRINGING INCRG LGT SNOW CHCS. ANOTHER SHORTWAVE...AND
ASSOCIATED COLD FRONT...IS EXPD TO CROSS THE RGN FRI EVE WITH
BETTER CHCS FOR SNOW SHOWERS. THE SNOW SHOWERS SHOULD CONTINUE
UNDER UPR TROFG AND LAKE/TERRAIN ENHANCEMENT LATER FRI NGT AND
SAT...THOUGH ACCUMULATIONS ARE EXPD TO REMAIN BELOW ADVISORY
CRITERIA AS DRY ARCTIC AIR RESULTS IN UNFAVORABLE MOISTURE CONTENT
IN THE SNOW GROWTH RGN. BLDG HIGH PRESSURE SAT NGT/SUN SHOULD
BRING DRY WEATHER.
WIND WITH SUFFICIENT PRES GRADIENT AND COLD TEMPS FRIDAY NIGHT
THRU SOMETIME SAT WILL LIKELY RESULT IN ADVISORY LVL WIND CHILLS
ACRS MUCH OF THE AREA. DIMINISHING WINDS MAY PROVIDE FOR LESSER
CHCS OF WIND CHILL ADVISORIES SAT NGT/ERLY SUN...THOUGH TEMPS NR
OR BELOW ZERO ARE EXPD. TEMPS WERE MODIFIED SLIGHTLY FROM
SUPERBLENDED GUIDANCE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
FAST MOVING SHORTWAVE WILL BRING A CHANCE FOR SNOW LATER SUNDAY
NIGHT INTO MONDAY AS TEMPERATURES MOVE TOWARD SEASONAL AVERAGES
TO START THE WEEK. MODELS HAVE DIFFERING SOLUTIONS FOR SOUTHERN
STREAM STORM SYSTEM INTENSIFYING AND MOVING NORTHEAST LATER
MONDAY INTO TUESDAY. SPLIT THE DIFFERENCE BETWEEN WPC PROGS AND
THE SUPERBLEND...WITH HIGHEST POPS INTO THE SOUTHEAST RIDGES.
THIS WILL BE FOLLOWED BY A CLIPPER TYPE SYSTEM WEDNESDAY WITH
CHANCE POPS. TEMPERATURES WILL BE NEAR THE SEASONAL NORM. HIGH
PRESSURE LOOKS TO GIVE A DRY DAY THURSDAY.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
SCT SNOW SHOWERS WILL STILL GIVE MVFR AT TIMES FOR NRN PORTS INTO
LATE AFTERNOON...BEFORE HIGH PRESSURE TURNS THE FLOW AND BEGINS TO
CLEAR SKIES THIS EVENING FOR VFR CONDITIONS. WEST WINDS 10-15KTS
WILL SUBSIDE AFTER SUNSET.
.OUTLOOK.../FRIDAY THROUGH TUESDAY/...
RESTRICTIONS WILL BE POSSIBLE IN SNOW SHOWERS LATER FRIDAY INTO
SATURDAY. THE NEXT CHANCE FOR WIDESPREAD IFR WILL BE WITH LOW
PRESSURE MONDAY AND TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
316 PM CST THU FEB 11 2016
.SHORT TERM: (Through Late Tonight)
Issued at 1230 PM CST Thu Feb 11 2016
A northwest flow shortwave now dropping southeastward into western
SD will move quickly through our area tonight. Light snow will
spread southeastward into northeast MO early this evening, then
through the St Louis metro area around midnight. Still looking like
a quick shot of dry, powdery snow with most places picking up to 1
inch of accumulation, but there may be a narrow band of 1-2 inches
extending from near IRK southeast through the St Louis metro area.
Latest NAM and HRRR model runs have the band a little further west
than previous model runs. Most of the accumulating snow should
shift southeast of our forecast area by 12Z Friday. Low
temperatures will be similar to the previous night, and around 5
degrees below normal.
GKS
.LONG TERM: (Friday through Next Thursday)
Issued at 316 PM CST Thu Feb 11 2016
A strong cold front will move southeastward through our forecast
area on Friday with strengthening winds as the surface pressure
gradient tightens as a strong 1040-1045 mb surface high builds
southeastward into the area from the northern Plains behind the cold
front. Temperatures may begin to fall in northeast MO behind the
front already by Friday afternoon. Much colder temperatures are
expected for Friday night and Saturday with wind chills down to
around 10 below zero late Friday night and early Saturday morning
across northeast MO and west central IL. Snow should spread
southeastward into at least northeast MO and west central IL late
Saturday night as low-mid level warm air advection increases ahead
of an approaching northern stream shortwave. It still appears that
the ECMWF model is a little too quick bringing precipitation into
our forecast area already be Saturday afternoon and evening with an
initially very dry boundary layer on the backside of the surface
ridge. The better chance of precipitation should occur on Sunday as
a southwesterly low level jet brings increasing low level moisture
into our area ahead of the shortwave. It is too early to pin down
exact snow totals, but it initially appears that 2-4 inches is
possible across northeast MO and west central IL with lesser amounts
of 1-2 inches further south for Saturday night and Sunday. Another
round of precipitation is expected, mainly on Monday, as a southern
stream shortwave and associated surface low pass south of our area.
This precipitation should be confined mainly to southeast MO and
southwest IL. With temperatures trending up as we head into the
next work week there may also be precipitation type issues with a
mix of snow, sleet and rain possible. Will keep the rest of the
forecast dry with a warming trend, although the ECMWF model does
depict some weaker weather systems bringing a brief period or two of
light QPF to our area. The GFS model is dry for the remainder of
the period after Monday with a dry cold frontal passage on Tuesday
afternoon and evening. Both the GFS and ECMWF models depict a warm
weather pattern by Thursday with upper level ridging over the region
along with strong s-swly low level winds likely leading to well
above normal temperatures.
GKS
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1237 PM CST Thu Feb 11 2016
SC has dissipated over taf sites, so will see VFR conditions
through early this evening as mid and high clouds stream in ahead
of next clipper system. Timing still similar to last set of tafs
with snow moving into KUIN/KCOU by 02z Friday and STL metro area
by 04z Friday. With onset of light snow, will see cigs dip down to
MVFR with brief IFR visbys as heavier bands of snow move through.
Snow to taper off between 09z and 10z Friday for taf sites, though
mvfr cigs to persist. KCOU on western periphery so should see
mvfr cigs scatter out by 16z Friday. As for winds, to remain from
the northeast to east as system moves through, then become light
and variable. By mid morning on Friday, winds to pickup from the
northwest.
Specifics for KSTL:
SC has dissipated over metro area, so will see VFR conditions
through early this evening as mid and high clouds stream in ahead
of next clipper system. Timing still similar to last set of tafs
with snow moving into STL metro area by 04z Friday. With onset of
light snow, will see cigs dip down to MVFR with brief IFR visbys
as heavier bands of snow move through. Snow to taper off by 10z
Friday, though mvfr cigs to persist for rest of taf forecast
period. As for winds, to remain from the northeast to east as
system moves through, then become light and variable by 10z Friday.
By 17z Friday, winds to pickup from the northwest around 10 kts.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1248 PM CST THU FEB 11 2016
.SHORT TERM: (Through Late Tonight)
Issued at 1230 PM CST Thu Feb 11 2016
A northwest flow shortwave now dropping southeastward into western
SD will move quickly through our area tonight. Light snow will
spread southeastward into northeast MO early this evening, then
through the St Louis metro area around midnight. Still looking like
a quick shot of dry, powdery snow with most places picking up to 1
inch of accumulation, but there may be a narrow band of 1-2 inches
extending from near IRK southeast through the St Louis metro area.
Latest NAM and HRRR model runs have the band a little further west
than previous model runs. Most of the accumulating snow should
shift southeast of our forecast area by 12Z Friday. Low
temperatures will be similar to the previous night, and around 5
degrees below normal.
GKS
.LONG TERM: (Tonight through Wednesday)
Issued at 225 AM CST Thu Feb 11 2016
...Light Snow Expected This Evening...
Next shortwave will be diving southeast in a similar manner to
yesterday`s and provide the area with another round of light snow.
It appears that this snow will be a little later in its arrival with
the main window of accumulation occurring from 6 pm to Midnight.
Once again have about an inch, give or take a few tenths, of snow
accumulation forecast from northeast Missouri to southwest Illinois.
This includes the Greater St. Louis Metropolitan Area.
Snow should taper off after midnight from northwest to southeast,
with a few flurries possible Friday morning. Thereafter, a very
cold air mass builds into the region Friday night and Saturday.
Low temperatures below zero are certainly possible Saturday
morning across the northern CWA.
The arctic high pressure quickly moves east though and by
Saturday night we could already have a band of warm advection snow
racing across the CWA. Better chance of accumulating snow appears
to occur on Sunday, but to be honest, medium range model guidance
has been flip flopping all over the place with this system the
past five days and still hasn`t landed on a common solution. Best
to leave PoPs at a chance for the period in question and give it a
few more runs before trying to nail down specifics.
Warm up looks on tap next week as the pattern changes with highs in
the 50s and maybe even 60s!
CVKING
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1237 PM CST Thu Feb 11 2016
SC has dissipated over taf sites, so will see VFR conditions
through early this evening as mid and high clouds stream in ahead
of next clipper system. Timing still similar to last set of tafs
with snow moving into KUIN/KCOU by 02z Friday and STL metro area
by 04z Friday. With onset of light snow, will see cigs dip down to
MVFR with brief IFR visbys as heavier bands of snow move through.
Snow to taper off between 09z and 10z Friday for taf sites, though
mvfr cigs to persist. KCOU on western periphery so should see
mvfr cigs scatter out by 16z Friday. As for winds, to remain from
the northeast to east as system moves through, then become light
and variable. By mid morning on Friday, winds to pickup from the
northwest.
Specifics for KSTL:
SC has dissipated over metro area, so will see VFR conditions
through early this evening as mid and high clouds stream in ahead
of next clipper system. Timing still similar to last set of tafs
with snow moving into STL metro area by 04z Friday. With onset of
light snow, will see cigs dip down to MVFR with brief IFR visbys
as heavier bands of snow move through. Snow to taper off by 10z
Friday, though mvfr cigs to persist for rest of taf forecast
period. As for winds, to remain from the northeast to east as
system moves through, then become light and variable by 10z Friday.
By 17z Friday, winds to pickup from the northwest around 10 kts.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
1231 PM CST THU FEB 11 2016
.SHORT TERM: (Through Late Tonight)
Issued at 1230 PM CST Thu Feb 11 2016
A northwest flow shortwave now dropping southeastward into western
SD will move quickly through our area tonight. Light snow will
spread southeastward into northeast MO early this evening, then
through the St Louis metro area around midnight. Still looking like
a quick shot of dry, powdery snow with most places picking up to 1
inch of accumulation, but there may be a narrow band of 1-2 inches
extending from near IRK southeast through the St Louis metro area.
Latest NAM and HRRR model runs have the band a little further west
than previous model runs. Most of the accumulating snow should
shift southeast of our forecast area by 12Z Friday. Low
temperatures will be similar to the previous night, and around 5
degrees below normal.
GKS
.LONG TERM: (Tonight through Wednesday)
Issued at 225 AM CST Thu Feb 11 2016
...Light Snow Expected This Evening...
Next shortwave will be diving southeast in a similar manner to
yesterday`s and provide the area with another round of light snow.
It appears that this snow will be a little later in its arrival with
the main window of accumulation occurring from 6 pm to Midnight.
Once again have about an inch, give or take a few tenths, of snow
accumulation forecast from northeast Missouri to southwest Illinois.
This includes the Greater St. Louis Metropolitan Area.
Snow should taper off after midnight from northwest to southeast,
with a few flurries possible Friday morning. Thereafter, a very
cold air mass builds into the region Friday night and Saturday.
Low temperatures below zero are certainly possible Saturday
morning across the northern CWA.
The arctic high pressure quickly moves east though and by
Saturday night we could already have a band of warm advection snow
racing across the CWA. Better chance of accumulating snow appears
to occur on Sunday, but to be honest, medium range model guidance
has been flip flopping all over the place with this system the
past five days and still hasn`t landed on a common solution. Best
to leave PoPs at a chance for the period in question and give it a
few more runs before trying to nail down specifics.
Warm up looks on tap next week as the pattern changes with highs in
the 50s and maybe even 60s!
CVKING
&&
.AVIATION: (For the 12z TAFs through 12z Friday Morning)
Issued at 544 AM CST Thu Feb 11 2016
VFR flight conditions expected today with band of cigs from 4-5kt
feet stretching from northern MO into southern Il slowly sinking
south this morning. In the wake of these clouds, mid-high clouds
will move into the area this afternoon in advance of the next
fast-moving system. Another band of light snow will spread into
the region early this evening and exit the area after 09z. KUIN
and the St. Louis region terminals will likely have a period of
MVFR- IFR flight conditions. Impacts at KCOU are a bit more
uncertain and MVFR conditions appear to be possible. Snow amounts
will be similar to yesterdays event, averaging near 1 inch.
Specifics for KSTL:
VFR flight conditions are expected today with band of cigs from
4-5kt during the morning. In the wake of these clouds, mid-high
clouds will move into the area this afternoon in advance of the
next fast-moving system. Light snow will spread into the terminal
mid-late evening and exit the area after 09z, bringing a period
of MVFR-IFR flight conditions. Snow amounts will be similar to
yesterdays event, averaging near 1 inch.
Glass
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
534 PM CST FRI FEB 12 2016
.SYNOPSIS...
ISSUED AT 330 PM CST FRI FEB 12 2016
ANALYSIS OF THE 18Z MSL DATA SHOWED HIGH PRESSURE FROM EASTERN
SASKATCHEWAN TO EASTERN SOUTH DAKOTA. THERE WAS A QUASI-STATIONARY
FRONT FROM NORTHWEST MONTANA...THROUGH EASTERN WYOMING...TO
SOUTHEAST COLORADO. IN THE WATER VAPOR IMAGERY...A PLUME OF MID-
LEVEL MOISTURE WAS INDICATED FROM THE PACIFIC OFF THE CALIFORNIA
COAST...ACROSS THE ROCKIES...AND ACROSS THE NORTHERN PLAINS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 330 PM CST FRI FEB 12 2016
ISENTROPIC UPGLIDE DEVELOPS IN THE 280-285K LAYER BY EARLY THIS
EVENING IN SOUTHWEST NEBRASKA OVER THE STATIONARY FRONT. THE LIFT IS
WEAK AND NOT IN A THICK LAYER IN THE SOUTHWEST AND THE WESTERN
SANDHILLS. THIS WOULD BE CONDUCIVE FOR THE DEVELOPMENT OF LIGHT
FREEZING DRIZZLE. BY EARLY SATURDAY...THE LIFT EXTENDS TO NEAR 500MB
IN THE 290-305K LAYER AND INTO THE DENDRITIC GROWTH ZONE OVER
CENTRAL AND NORTH CENTRAL NEBRASKA...THUS FAVORING LIGHT SNOW. BY
EARLY AFTERNOON SATURDAY...THE LOW LEVEL TEMPERATURES WARM ENOUGH
THAT THE THREAT OF FREEZING DRIZZLE DIMINISHES IN THE SANDHILLS AND
SOUTHWEST BUT THE LOW STRATUS IS LIKELY TO CONTINUE THROUGH LATE
SATURDAY AFTERNOON OR EARLY EVENING.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 330 PM CST FRI FEB 12 2016
MID TERM...SATURDAY NIGHT THROUGH MONDAY...IN THE MIDTERM...THE
THREAT FOR LIGHT SNOW IN THE NORTH SATURDAY NIGHT...FOLLOWED BY A
THREAT FOR LIGHT PCPN IN THE WEST SUNDAY NIGHT WILL BE THE MAIN
FORECAST CONCERNS. FOR SATURDAY NIGHT...A MID LEVEL TROUGH WILL
APPROACH THE WESTERN DAKOTAS SATURDAY EVENING. STRONG MID LEVEL
FRONTOGENESIS AND DECENT MID LEVEL WAA WILL SPREAD EAST ACROSS SOUTH
DAKOTA SATURDAY NIGHT. THIS WILL LEAD TO SNOWFALL ACROSS SOUTH
DAKOTA. SOME WEAK LIFT WITH THIS SYSTEM WILL TRACK ACROSS FAR SRN
SOUTH DAKOTA AND FAR NRN NEBRASKA IN ASSOCIATION WITH THIS MAIN
UPPER LEVEL SYSTEM SATURDAY NIGHT...AND LOW CHANCES FOR LIGHT SNOW
WERE RETAINED ROUGHLY NORTH OF A LINE FROM HAY SPRINGS TO EWING. ANY
ACCUMULATIONS ACROSS NORTHERN NEBRASKA WILL BE VERY LIGHT...ON THE
ORDER OF A HALF AN INCH TO AN INCH. AFTER MAINLY DRY CONDS ON
SUNDAY...A JET STREAK AND SECONDARY MID LEVEL DISTURBANCE WILL DROP
SOUTH FROM EASTERN WYOMING INTO NERN COLORADO AND WESTERN KANSAS.
THESE LOCATIONS...ALONG WITH FAR SWRN NEBRASKA WILL BE IN THE
FAVORABLE LEFT FRONT QUAD OF THE JET STREAK SUNDAY NIGHT...AND
INSERTED SOME SLIGHT CHANCE POPS ACROSS FAR SWRN NEBRASKA. THIS
SYSTEM WILL BE FAIRLY MOISTURE STARVED GIVEN THE EXITING SYSTEM
SATURDAY NIGHT...SO WILL KEEP POPS AND QPF/S MINIMAL. ON MONDAY INTO
MONDAY NIGHT...RIDGING WILL BUILD INTO THE NORTHERN
ROCKIES...FORCING A WARM FRONT THROUGH THE DAKOTAS AND NORTHERN
NEBRASKA. AS THIS FEATURE PROGRESSES EAST MONDAY NIGHT...A FAVORABLE
SET UP FOR PCPN WILL EXIST ACROSS THE DAKOTAS...AND NORTHERN
NEBRASKA. ATTM...THE BEST DYNAMICS WILL BE LOCATED OVER EASTERN
SOUTH DAKOTA IN CLOSEST PROXIMITY TO THE LEFT FRONT QUAD OF THE JET.
HOWEVER...WEAK LIFT IS NOTED WITH THIS FRONT OVER FAR NORTHWESTERN
AND NORTHEASTERN PORTIONS OF THE FORECAST AREA MONDAY NIGHT.
TEMPERATURES WILL BE WARM ENOUGH MONDAY EVENING TO SUPPORT ALL
RAIN...WITH A RAIN SNOW MIX POSSIBLE OVERNIGHT AS TEMPERATURES
BOTTOM OUT IN THE LOWER 30S.
LONG RANGE...TUESDAY THROUGH FRIDAY...RIDGING ALOFT WILL BUILD INTO
THE INTER MOUNTAIN WEST AND CENTRAL CONUS NEXT WEEK. THE RIDGE WILL
AMPLIFY FURTHER BY THE END OF THE WEEK WITH VERY WARM AIR PUSHING
INTO THE REGION. GUIDANCE TEMPERATURES HAVE TRENDED HIGHER THIS
MORNING AND ARE HINTING AT 60S BY THE END OF NEXT WEEK. DECIDED TO
TREND TEMPS HIGHER IN THE EXTENDED...BUT NOT AS WARM AS THE
OPERATIONAL ECM AND MEX GUIDANCE IS INDICATING. THE ENSEMBLE SPREADS
FOR TEMPS AFTER MIDWEEK NEXT WEEK BEGIN TO INCREASE...PARTICULARLY
ON THURSDAY AND FRIDAY. WITH THIS IN MIND...WILL TAKE A MORE
CONSERVATIVE APPROACH TO INCREASING HIGHS WITH THIS FCST PACKAGE.
FWIW...H85 TEMPS THURSDAY AFTERNOON PEAK OUT AT AROUND 16 TO 18C
ACROSS FAR SWRN NEBRASKA PER THE LATEST GFS AND ECMWF SOLNS. IF THIS
VERIFIES...WE COULD SEE HIGHS NEXT THURSDAY APPROACHING THE 70
DEGREE MARK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 533 PM CST FRI FEB 12 2016
VFR CIGS ACROSS NCNTL NEB SHOULD FILL IN AND BECOME IFR IN LIGHT-
FZDZSN AS UPSLOPE WINDS BECOME SOUTH AND SOUTHEAST THIS EVENING.
MVFR/IFR CIGS ARE EXPECTED ELSEWHERE. THE RAP MODEL APPEARED TO
HAVE THE BEST HANDLE ON THE PCPN.
MVFR/IFR CIGS ARE EXPECTED SATURDAY. LIGHT -FZDZSN IS POSSIBLE
AGAIN AS A WARM FRONT SHARPENS UP ACROSS WRN NEB. THE GFS LOOKED
THE BEST IN THIS REGARD.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SPRINGER
SHORT TERM...SPRINGER
LONG TERM...BUTTLER
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1147 AM CST THU FEB 11 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CST THU FEB 11 2016
SATELLITE AND OBSERVATIONS SHOW STRATUS THAT HAS BEEN MOVING TO THE
SOUTH ACROSS THE FORECAST AREA OVERNIGHT. SO FAR IT HAS MADE IT
ACROSS MOST OF THE NEBRASKA PORTION OF THE FORECAST AREA AND WILL BE
MOVING INTO THE KANSAS PORTION.
THE FIRST CONCERN WITH THIS IS THERE WAS QUITE A BIT OF SNOW MELTING
YESTERDAY SO THERE IS GOOD LOW LEVEL MOISTURE. WINDS HAVE BEEN FROM
THE NORTH AND FAIRLY LIGHT. WITH THE EDGE OF THE STRATUS ACROSS THE
AREA THERE COULD BE A LITTLE FOG. THE HRRR AND THE SREF BOTH HAVE
THE LOWEST VISIBILITIES IN THE WEST. SO FAR THERE HAS BEEN LITTLE
INDICATION OF ANY FOG. WILL KEEP SOME MENTION OF PATCHY FOG WITH A
FEW AREAS OF FOG IN THE FAR WEST. WILL HAVE TO WATCH TO SEE IF THE
VISIBILITY DROPS AS WE GET CLOSER TO SUNRISE. THE MAIN DIFFERENCE
SEEMS TO BE THE MODELS THAT BRING THE LOWEST VISIBILITIES ALSO HAVE
EASTERLY WINDS AND THE CURRENT WINDS ARE MORE NORTH.
THERE COULD BE A LITTLE OF THE PATCHY FOG THAT LINGERS INTO THE
MORNING HOURS. THE CLOUDS SHOULD HANG AROUND FOR MUCH OF THE
DAY...BUT TOWARD THE END OF THE DAY THE CLOUDS SHOULD START TO
RECEDE TO THE EAST AGAIN. TEMPERATURES WILL BE A LITTLE COOLER TODAY
THAN YESTERDAY.
ANOTHER WEAK COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE
THIS AFTERNOON AND EVENING. THIS SHOULD HELP TO MOVE THE CLOUDS OUT
OF THE AREA...BUT TEMPERATURES WILL NOT BE VERY COLD BEHIND THE
FRONT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 350 AM CST THU FEB 11 2016
THE END OF THE WORK WEEK WILL BE SLIGHTLY COOLER AS SURFACE HIGH
PRESSURE MOVES EAST ACROSS THE AREA. WINDS WILL BECOME SOUTHERLY
FRIDAY NIGHT. THE PLAINS SITS UNDER NORTHWESTERLY UPPER LEVEL FLOW
AND A DISTURBANCE WILL MOVE SOUTH INTO THE UPPER TROUGH OVER THE
EAST CAUSING A CHANCE FOR LIGHT PRECIPITATION OVERNIGHT FRIDAY AND
INTO SATURDAY. CONFIDENCE IS NOT OVERLY HIGH...THE LOWEST LEVELS
REMAIN THE MOST SATURATED...BUT EARLY ON THERE IS ENOUGH DEPTH AND
IT IS COLD ENOUGH TO BEGIN AS SNOW BEFORE FREEZING DRIZZLE LOOKS TO
BE THE MAIN PRECIP TYPE. NOT EXPECTING MUCH IN THE WAY OF SNOW
ACCUMULATION. DRYER AIR WILL MOVE IN FROM THE NORTHEAST ALLOWING
OVERNIGHT TEMPERATURES FRIDAY NIGHT TO PLUMMET INTO THE SINGLE
DIGITS AND TEENS...THE COLDEST NIGHT OF THE FORECAST.
A MORE POTENT DISTURBANCE WILL DIVE ACROSS THE CENTRAL PLAINS
SATURDAY NIGHT WHICH WILL AID IN THE DEVELOPMENT OF PRECIPITATION.
THE BEST CHANCES FOR PRECIP LOOK TO BE OVER NORTH AND EASTERN
NEBRASKA...BUT SOME LIGHT PRECIP MAY OCCUR OVER SOUTH CENTRAL
NEBRASKA. THE COLUMN OF AIR WILL BE COLD ENOUGH FOR SNOW TO BE THE
MAIN PRECIP TYPE WITH THIS.
SUNDAY AFTER THIS DISTURBANCE MOVES OVERHEAD THE ASSOCIATED FRONT
WILL CAUSE WINDS TO BECOME WESTERLY TO NORTHWESTERLY. DOWNSLOPE
FLOW WILL AID TEMPERATURES TO RISE BACK INTO THE 40S ACROSS THE
AREA.
ANOTHER BRIEF DISTURBANCE WILL MOVE OVERHEAD SUNDAY NIGHT...THIS
COULD BRING ANOTHER BRIEF CHANCE FOR PRECIP...BUT CONFIDENCE IS
LOW ON THIS FEATURE.
THE FIRST HALF OF THE WORK WEEK WILL HAVE A WARMING TREND AS
UPPER LEVEL RIDGING BUILDS INTO THE AREA. TEMPERATURES WILL WARM
EACH DAY FROM MONDAY THROUGH WEDNESDAY WITH HIGHS REACHING INTO
THE 50S BY MID WEEK.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1130 AM CST THU FEB 11 2016
PLENTY OF LOW LEVEL STRATUS WILL CONTINUE TO STREAM ACROSS THE
REGION THROUGH THE SHORT TERM PERIODS. EXPECT IFR CIGS TO LIFT TO
MVFR LEVELS LATE THIS AFTERNOON...ONLY TO DROP BACK DOWN TO IFR
LEVELS DURING THE EVENING HOURS. WHILE MODELS ONCE AGAIN ARE
INDICATING WE COULD SEE SOME LOWERED VSBYS...OPTED TO ONLY INCLUDE
MVFR VSBYS FOR THE TIME BEING AS CONDITIONS DO NOT LOOK ANY MORE
FAVORABLE FOR FOG DEVELOPMENT OVERNIGHT THAN THEY DID THIS
MORNING. OTHERWISE...EXPECT WINDS TO SHIFT AND BECOME MORE
NORTHERLY OVERNIGHT AS A COLD FRONT DROPS SOUTH ACROSS THE
REGION...GENERALLY REMAINING 12KTS OF LESS THROUGH THE PERIOD.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...BILLINGS WRIGHT
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS HASTINGS NE
524 AM CST THU FEB 11 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CST THU FEB 11 2016
SATELLITE AND OBSERVATIONS SHOW STRATUS THAT HAS BEEN MOVING TO THE
SOUTH ACROSS THE FORECAST AREA OVERNIGHT. SO FAR IT HAS MADE IT
ACROSS MOST OF THE NEBRASKA PORTION OF THE FORECAST AREA AND WILL BE
MOVING INTO THE KANSAS PORTION.
THE FIRST CONCERN WITH THIS IS THERE WAS QUITE A BIT OF SNOW MELTING
YESTERDAY SO THERE IS GOOD LOW LEVEL MOISTURE. WINDS HAVE BEEN FROM
THE NORTH AND FAIRLY LIGHT. WITH THE EDGE OF THE STRATUS ACROSS THE
AREA THERE COULD BE A LITTLE FOG. THE HRRR AND THE SREF BOTH HAVE
THE LOWEST VISIBILITIES IN THE WEST. SO FAR THERE HAS BEEN LITTLE
INDICATION OF ANY FOG. WILL KEEP SOME MENTION OF PATCHY FOG WITH A
FEW AREAS OF FOG IN THE FAR WEST. WILL HAVE TO WATCH TO SEE IF THE
VISIBILITY DROPS AS WE GET CLOSER TO SUNRISE. THE MAIN DIFFERENCE
SEEMS TO BE THE MODELS THAT BRING THE LOWEST VISIBILITIES ALSO HAVE
EASTERLY WINDS AND THE CURRENT WINDS ARE MORE NORTH.
THERE COULD BE A LITTLE OF THE PATCHY FOG THAT LINGERS INTO THE
MORNING HOURS. THE CLOUDS SHOULD HANG AROUND FOR MUCH OF THE
DAY...BUT TOWARD THE END OF THE DAY THE CLOUDS SHOULD START TO
RECEDE TO THE EAST AGAIN. TEMPERATURES WILL BE A LITTLE COOLER TODAY
THAN YESTERDAY.
ANOTHER WEAK COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE
THIS AFTERNOON AND EVENING. THIS SHOULD HELP TO MOVE THE CLOUDS OUT
OF THE AREA...BUT TEMPERATURES WILL NOT BE VERY COLD BEHIND THE
FRONT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 350 AM CST THU FEB 11 2016
THE END OF THE WORK WEEK WILL BE SLIGHTLY COOLER AS SURFACE HIGH
PRESSURE MOVES EAST ACROSS THE AREA. WINDS WILL BECOME SOUTHERLY
FRIDAY NIGHT. THE PLAINS SITS UNDER NORTHWESTERLY UPPER LEVEL FLOW
AND A DISTURBANCE WILL MOVE SOUTH INTO THE UPPER TROUGH OVER THE
EAST CAUSING A CHANCE FOR LIGHT PRECIPITATION OVERNIGHT FRIDAY AND
INTO SATURDAY. CONFIDENCE IS NOT OVERLY HIGH...THE LOWEST LEVELS
REMAIN THE MOST SATURATED...BUT EARLY ON THERE IS ENOUGH DEPTH AND
IT IS COLD ENOUGH TO BEGIN AS SNOW BEFORE FREEZING DRIZZLE LOOKS TO
BE THE MAIN PRECIP TYPE. NOT EXPECTING MUCH IN THE WAY OF SNOW
ACCUMULATION. DRYER AIR WILL MOVE IN FROM THE NORTHEAST ALLOWING
OVERNIGHT TEMPERATURES FRIDAY NIGHT TO PLUMMET INTO THE SINGLE
DIGITS AND TEENS...THE COLDEST NIGHT OF THE FORECAST.
A MORE POTENT DISTURBANCE WILL DIVE ACROSS THE CENTRAL PLAINS
SATURDAY NIGHT WHICH WILL AID IN THE DEVELOPMENT OF PRECIPITATION.
THE BEST CHANCES FOR PRECIP LOOK TO BE OVER NORTH AND EASTERN
NEBRASKA...BUT SOME LIGHT PRECIP MAY OCCUR OVER SOUTH CENTRAL
NEBRASKA. THE COLUMN OF AIR WILL BE COLD ENOUGH FOR SNOW TO BE THE
MAIN PRECIP TYPE WITH THIS.
SUNDAY AFTER THIS DISTURBANCE MOVES OVERHEAD THE ASSOCIATED FRONT
WILL CAUSE WINDS TO BECOME WESTERLY TO NORTHWESTERLY. DOWNSLOPE
FLOW WILL AID TEMPERATURES TO RISE BACK INTO THE 40S ACROSS THE
AREA.
ANOTHER BRIEF DISTURBANCE WILL MOVE OVERHEAD SUNDAY NIGHT...THIS
COULD BRING ANOTHER BRIEF CHANCE FOR PRECIP...BUT CONFIDENCE IS
LOW ON THIS FEATURE.
THE FIRST HALF OF THE WORK WEEK WILL HAVE A WARMING TREND AS
UPPER LEVEL RIDGING BUILDS INTO THE AREA. TEMPERATURES WILL WARM
EACH DAY FROM MONDAY THROUGH WEDNESDAY WITH HIGHS REACHING INTO
THE 50S BY MID WEEK.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 521 AM CST THU FEB 11 2016
LOW STRATUS WILL CONTINUE ACROSS THE AREA THROUGH MUCH OF THE
PERIOD. THE LOWEST CEILINGS WILL BE EARLY THIS MORNING THEN
CEILINGS WILL INCREASE A LITTLE AND THERE COULD BE A FEW IN AND
OUT PERIODS DURING THE AFTERNOON. HAVE SEEN LITTLE IN THE WAY OF
FOG THIS MORNING SO HAVE LEFT IT OUT FOR NOW.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...BILLINGS WRIGHT
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
350 AM CST THU FEB 11 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CST THU FEB 11 2016
SATELLITE AND OBSERVATIONS SHOW STRATUS THAT HAS BEEN MOVING TO THE
SOUTH ACROSS THE FORECAST AREA OVERNIGHT. SO FAR IT HAS MADE IT
ACROSS MOST OF THE NEBRASKA PORTION OF THE FORECAST AREA AND WILL BE
MOVING INTO THE KANSAS PORTION.
THE FIRST CONCERN WITH THIS IS THERE WAS QUITE A BIT OF SNOW MELTING
YESTERDAY SO THERE IS GOOD LOW LEVEL MOISTURE. WINDS HAVE BEEN FROM
THE NORTH AND FAIRLY LIGHT. WITH THE EDGE OF THE STRATUS ACROSS THE
AREA THERE COULD BE A LITTLE FOG. THE HRRR AND THE SREF BOTH HAVE
THE LOWEST VISIBILITIES IN THE WEST. SO FAR THERE HAS BEEN LITTLE
INDICATION OF ANY FOG. WILL KEEP SOME MENTION OF PATCHY FOG WITH A
FEW AREAS OF FOG IN THE FAR WEST. WILL HAVE TO WATCH TO SEE IF THE
VISIBILITY DROPS AS WE GET CLOSER TO SUNRISE. THE MAIN DIFFERENCE
SEEMS TO BE THE MODELS THAT BRING THE LOWEST VISIBILITIES ALSO HAVE
EASTERLY WINDS AND THE CURRENT WINDS ARE MORE NORTH.
THERE COULD BE A LITTLE OF THE PATCHY FOG THAT LINGERS INTO THE
MORNING HOURS. THE CLOUDS SHOULD HANG AROUND FOR MUCH OF THE
DAY...BUT TOWARD THE END OF THE DAY THE CLOUDS SHOULD START TO
RECEDE TO THE EAST AGAIN. TEMPERATURES WILL BE A LITTLE COOLER TODAY
THAN YESTERDAY.
ANOTHER WEAK COLD FRONT WILL MOVE THROUGH THE FORECAST AREA LATE
THIS AFTERNOON AND EVENING. THIS SHOULD HELP TO MOVE THE CLOUDS OUT
OF THE AREA...BUT TEMPERATURES WILL NOT BE VERY COLD BEHIND THE
FRONT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 350 AM CST THU FEB 11 2016
THE END OF THE WORK WEEK WILL BE SLIGHTLY COOLER AS SURFACE HIGH
PRESSURE MOVES EAST ACROSS THE AREA. WINDS WILL BECOME SOUTHERLY
FRIDAY NIGHT. THE PLAINS SITS UNDER NORTHWESTERLY UPPER LEVEL FLOW
AND A DISTURBANCE WILL MOVE SOUTH INTO THE UPPER TROUGH OVER THE
EAST CAUSING A CHANCE FOR LIGHT PRECIPITATION OVERNIGHT FRIDAY AND
INTO SATURDAY. CONFIDENCE IS NOT OVERLY HIGH...THE LOWEST LEVELS
REMAIN THE MOST SATURATED...BUT EARLY ON THERE IS ENOUGH DEPTH AND
IT IS COLD ENOUGH TO BEGIN AS SNOW BEFORE FREEZING DRIZZLE LOOKS TO
BE THE MAIN PRECIP TYPE. NOT EXPECTING MUCH IN THE WAY OF SNOW
ACCUMULATION. DRYER AIR WILL MOVE IN FROM THE NORTHEAST ALLOWING
OVERNIGHT TEMPERATURES FRIDAY NIGHT TO PLUMMET INTO THE SINGLE
DIGITS AND TEENS...THE COLDEST NIGHT OF THE FORECAST.
A MORE POTENT DISTURBANCE WILL DIVE ACROSS THE CENTRAL PLAINS
SATURDAY NIGHT WHICH WILL AID IN THE DEVELOPMENT OF PRECIPITATION.
THE BEST CHANCES FOR PRECIP LOOK TO BE OVER NORTH AND EASTERN
NEBRASKA...BUT SOME LIGHT PRECIP MAY OCCUR OVER SOUTH CENTRAL
NEBRASKA. THE COLUMN OF AIR WILL BE COLD ENOUGH FOR SNOW TO BE THE
MAIN PRECIP TYPE WITH THIS.
SUNDAY AFTER THIS DISTURBANCE MOVES OVERHEAD THE ASSOCIATED FRONT
WILL CAUSE WINDS TO BECOME WESTERLY TO NORTHWESTERLY. DOWNSLOPE
FLOW WILL AID TEMPERATURES TO RISE BACK INTO THE 40S ACROSS THE
AREA.
ANOTHER BRIEF DISTURBANCE WILL MOVE OVERHEAD SUNDAY NIGHT...THIS
COULD BRING ANOTHER BRIEF CHANCE FOR PRECIP...BUT CONFIDENCE IS
LOW ON THIS FEATURE.
THE FIRST HALF OF THE WORK WEEK WILL HAVE A WARMING TREND AS
UPPER LEVEL RIDGING BUILDS INTO THE AREA. TEMPERATURES WILL WARM
EACH DAY FROM MONDAY THROUGH WEDNESDAY WITH HIGHS REACHING INTO
THE 50S BY MID WEEK.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1120 PM CST WED FEB 10 2016
STRATUS CONTINUES TO PUSH SOUTH INTO THE TERMINAL AREAS IN THE
NEXT FEW HOURS. EXPECT THE LOWEST CEILINGS TO BE A FEW HOURS
EITHER SIDE OF SUNRISE. CEILINGS SHOULD INCREASE A LITTLE DURING
THE DAY...BUT THE STRATUS SHOULD LINGER THROUGH MUCH OF THE
PERIOD. DUE TO SNOW MELT TODAY...LIGHT WINDS AND THE EDGE OF THE
STRATUS AROUND THE AREA...THERE COULD BE SOME FOG. THE LOCATION
AND HOW DENSE IT GETS IS STILL IN QUESTION AT THIS TIME.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...BILLINGS WRIGHT
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
333 AM CST THU FEB 11 2016
.SYNOPSIS...
ISSUED AT 333 AM CST THU FEB 11 2016
A BACKDOOR COLD FRONT HAS USHERED IN STRATUS ACROSS THE NORTHEASTERN
HALF OF THE FA. SOME LIGHT FOG INDICATED AT THEDFORD AND PINE RIDGE
AS OF 08Z. TEMPERATURES RANGING FROM THE MID 20S TO LOW 30S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CST THU FEB 11 2016
THE MAIN FORECAST CONCERNS WILL BE A DISTURBANCE DROPPING SOUTHEAST
FROM THE DAKOTAS INTO NORTHEAST NEBRASKA TODAY AND THE EFFECTS THIS
HAS ON HIGH TEMPERATURES. SURFACE LOW PRESSURE ON THE SOUTHWEST SIDE
OF THE DISTURBANCE WILL VEER SURFACE WINDS TO THE WEST AND NORTHWEST
ACROSS THE WESTERN HALF OF THE FA AND ALLOWING HIGHS TO RISE TO 45
TO 50 DEGREES. THE MORNING STRATUS SHOULD BREAK UP IN THE
AFTERNOON WITH MAINLY HIGH CLOUDINESS LINGERING.
FURTHER EAST...HIGHS FROM THE MID 30S TO LOW 40S AFFECTED BY
SOUTHERLY WINDS AND PERSISTENT STRATUS. HAVE INTRODUCED A 20-30 POP
ACROSS BOYD COUNTY AND FAR NRN HOLT COUNTY MAINLY BETWEEN 10
AM AND 3 PM ON THE FAR WESTERN EDGE OF THE DISTURBANCE.
FOR TONIGHT...AN ARCTIC HIGH WILL BEGIN TO BUILD INTO THE REGION
WITH STRATUS LIKELY TO PUSH BACK INTO WESTERN NEBRASKA. THERE COULD
BE SOME VERY LIGHT PRECIPITATION AFTER MIDNIGHT AND SOUNDING
PROFILES FAVOR SOME CHANCE FOR FREEZING DRIZZLE. HAVE NOT INTRODUCED
MENTION YET...AND IF IT WOULD OCCUR IT WOULD FAVOR AREAS ACROSS THE
NORTHEAST HALF OF THE FA. LOWS TONIGHT FROM THE UPPER 20S CENTRAL
SANDHILLS AND SOUTHWEST TO NEAR 25 NORTH.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 333 AM CST THU FEB 11 2016
ARCTIC HIGH PRESSURE WILL BUILD SOUTHEAST ACROSS THE NORTHERN PLAINS
ON FRIDAY AND WILL FORCE A FRONT SOUTHWEST ACROSS THE SANDHILLS. THE
FORECAST CALLS FOR MUCH COOLER TEMPERATURES FRIDAY AFTERNOON...WITH
HIGHS RANGING FROM THE MID TO UPPER 20S ACROSS OUR FAR NORTHEASTERN
ZONES...TO NEAR 40 OVER THE HIGHEST TERRAIN OF THE SOUTHWEST. THE
FRONT STALLS FRIDAY EVENING ACROSS SOUTHWEST NEB AND THE PANHANDLE
AS A WEAK AREA OF MID LEVEL WARM AIR ADVECTION LIFTS EAST ATOP THE
FRONT. PROXIMITY SOUNDINGS ACROSS THE SANDHILLS AND EASTERN
PANHANDLE INITIALLY REVEAL SUFFICIENT MOISTURE AND FAVORABLE THERMAL
PROFILES FOR ALL SNOW...BUT INTO THE OVERNIGHT SOUNDINGS FAVOR MORE
LIGHT FREEZING DRIZZLE OVER SNOW. THE FOCUS OF THE DRIZZLE WILL
SPREAD EAST TOWARD DAWN AND ON SATURDAY AS A WARM FRONT PUSHES EAST
ACROSS THE SANDHILLS. TEMPERATURES ON SATURDAY WILL MODERATE
SLIGHTLY BEHIND THE WARM FRONT...WITH HIGHS ANTICIPATED TO TOP OUT
IN THE LOWER TO MID 40S ACROSS SW NEB AND THE EASTERN PANHANDLE.
ACROSS NORTH CENTRAL NEBRASKA...THE LATEST GUIDANCE INDICATES HIGHS
OF ONLY THE MID 20S.
THE NEXT POTENTIAL PRECIPITATION PRODUCER ARRIVES OVER NORTHERN
NEBRASKA SATURDAY NIGHT. THE BEST LIFT GENERALLY IS INDICATED
ACROSS THE DAKOTAS...BUT THE ECMWF CONTINUES TO PUT DOWN QPF ACROSS
THE NORTHERN ZONES. WILL RETAIN THE SLIGHT CHANCE TO LOW END CHANCE
POPS ACROSS OUR NORTH.
FOR SUNDAY AND BEYOND...THE SYSTEM EJECTS TO THE EAST...BUT
FAVORABLE UPPER LEVEL DYNAMICS FOR ADDITIONAL LIGHT QPF CHANCES
REMAIN ACROSS THE REGION. WARMING TEMPERATURES THOUGH ARE LIKELY AS
LOWER AND MID LEVEL WAA SPREADS EAST FROM THE ROCKY MOUNTAIN WEST.
BEYOND SUNDAY THE WARMING TEMPERATURES CONTINUE WITH HIGHS
APPROACHING 60 SOUTH OF I80 BY TUESDAY. THE WARM TEMPERATURES LOOK
TO REMAIN THROUGH AT LEAST MID-WEEK AS RIDGING PREVAILS TO THE WEST
OF THE CWA. ARCTIC HIGH PRESSURE IS SHOWN TO DROP SOUTHEAST FROM
THE CANADIAN PRAIRIES MID-WEEK...BUT THE GFS AND ECMWF ARE AT ODDS
AS TO HOW FAR WEST THE COOL AIR BUILDS. FOR NOW WILL NOT MAKE ANY
CHANGES TO THE BLENDED EXTENDED PROCEDURE...WHICH SUGGEST THE WARMER
TEMPERATURES. PRECIPITATION CHANCES WILL BE LIMITED BEYOND SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1126 PM CST WED FEB 10 2016
THE RAP MODEL HAS DONE WELL WITH THE MVFR/IFR CIGS MOVING INTO
NEB THIS EVENING AND IT IS THE BASIS FOR THE FORECAST. THE MODEL
IS SIMILAR TO THE FASTER GFS AND SUGGESTS MOST OF THE FCST AREA
WOULD BE VFR BY 22Z THURSDAY.
LIFR IS POSSIBLE FOG OVERNIGHT ALONG I-80 AND HIGHWAY 61. MVFR/IFR
IS GENERALLY EXPECTED FROM 16Z-20Z.
MVFR CIGS MOVE IN AGAIN THURSDAY EVENING WITH THE NEXT ARCTIC
FRONT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1126 PM CST WED FEB 10 2016
.SYNOPSIS...
ISSUED AT 324 PM CST WED FEB 10 2016
MILD AIR HAS PUSHED INTO ALL OF WESTERN AND NORTH CENTRAL
NEBRASKA THIS AFTERNOON AS THE ARCTIC FRONT HAS RETREATED EAST...ALL
THE WAY TO FAR NORTHEASTERN NEBRASKA. WITH CLEAR SKIES AND WESTERLY
WINDS...TEMPERATURES HAVE SURGED INTO THE UPPER 50S TO LOWER 60S OVER
NON SNOW COVERED AREAS OF THE CENTRAL SANDHILLS AND PORTIONS OF
NORTH CENTRAL NEBRASKA. OVER SNOW COVERED AREAS...TEMPERATURES
WERE IN THE UPPER 40S TO LOWER 50S. THE H5 PATTERN TODAY REMAINED
HIGHLY AMPLIFIED...AND HAS SHIFTED 100 TO 200 MILES FURTHER EAST
TDY. RIDGING EXTENDED FROM SRN NEVADA...NORTH INTO SRN YUKON WHILE
A TROUGH EXTENDED FROM THE NRN GREAT LAKES...SOUTH TO EASTERN
PORTIONS OF THE GULF OF MEXICO AND SRN FLORIDA. IN BETWEEN THE
TROUGH AND RIDGE...A TIGHT NWRLY H5 GRADIENT WAS NOTED AND
EXTENDED FROM SASKATCHEWAN INTO THE BOOT HEEL OF MISSOURI.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 324 PM CST WED FEB 10 2016
TEMPS IN THE 50S AND 60S TODAY HAVE RESULTED IN SOME DECENT SNOW
MELT. MEANWHILE A BACK DOOR COLD FRONT WILL DRIFT SW INTO THE
REGION. THIS FRONT WILL STALL ACROSS CENTRAL NEBRASKA. THIS WILL
CREATE SOME CONCERNS FOR TEMPS...AS WARM TEMPS TO THE WEST OF THE
FRONT AND COOL TEMPS TO THE EAST. FOR NOW WILL MODEL BLEND THE
LOCATION OF THE FRONT...WITH THE WEST AND SNOW FREE AREAS TO WARM
TOMORROW AFTERNOON TO NEAR 50. LIKELY GOING TO HOLD IN THE 30S TO
AROUND 40 IN THE EAST.
FOR TONIGHT WILL AGAIN BE FOLLOWING THE MEANDERING FRONT. SOME
SATURATION AND WEAK LIFT IN THE BL COULD BE ENOUGH FOR SOME FREEZING
DRIZZLE ALONG AND EAST OF THE FRONT. THIS WILL MAINLY IMPACT N
CENTRAL...ALTHOUGH CONFIDENCE IS LOW SO ONLY INCLUDED PATCHY
WORDING. ELSEWHERE...THE ADDED MOISTURE IN THE BL FROM THE SNOW MELT
SHOULD CREATE A RICH ENVIRONMENT FOR AT LEAST PATCHY FOG. WILL HAVE
TO MONITOR FOR POSSIBLE PATCHY DENSE FOG. DEW PTS HAVE INCREASED
INTO THE LOWER 30S...WHILE EXPECTED LOW TEMPS TONIGHT IN THE LOWER
TO MID 20S.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 324 PM CST WED FEB 10 2016
MID TERM...THURSDAY NIGHT THROUGH SATURDAY...A COUPLE OF FORECAST
CONCERNS HIGHLIGHT THE MID RANGE. THE FIRST IS
TEMPERATURES...PARTICULARLY ON FRIDAY THROUGH SATURDAY...THEN THE
THREAT FOR LIGHT SNOW FRIDAY...FOLLOWED BY A FREEZING DRIZZLE/LIGHT
SNOW THREAT FOR LATE FRIDAY NIGHT INTO SATURDAY. FOR THURSDAY
NIGHT...THE ARCTIC FRONT WILL BE ORIENTED ACROSS THE FAR NERN CWA.
SURFACE LOW PRESSURE WILL TRACK ALONG THIS FRONT FROM WEST CENTRAL
SOUTH DAKOTA INTO NERN NEBRASKA THURSDAY EVENING. AS THE LOW
APPROACHES...WEAK LIFT ALONG THE FRONT WILL BE PRESENT IN BOYD AND
NERN HOLT COUNTIES. WITH THIS IN MIND...DECIDED TO PLACE SOME SLIGHT
CHANCE POPS FOR SNOW IN THESE AREAS. THE FRONT WILL SURGE NORTHEAST
AHEAD OF THE LOWS TRACK...THEN QUICKLY SURGE SOUTHWEST OVERNIGHT AS
THE SURFACE LOW TRACKS INTO SERN NEBRASKA. ARCTIC HIGH PRESSURE WILL
BEGIN TO BUILD INTO THE EASTERN DAKOTAS LATE THURSDAY NIGHT INTO
FRIDAY...FORCING THE ARCTIC FRONT SOUTHWEST INTO WESTERN AND NORTH
CENTRAL NEBRASKA. BY FRIDAY EVENING...THE FRONT WILL BE ORIENTED
ACROSS THE PANHANDLE. HIGHS WERE LOWERED SIGNIFICANTLY FOR FRIDAY AS
THE FRONTAL TIMING IS NOW 6 TO 12 HRS EARLIER THAN WHAT WAS
INDICATED WITH YESTERDAY/S MODEL SOLNS. THAT BEING SAID...WITH THE
COMBINATION OF CLOUDS AND EASTERLY WINDS...HIGHS FRIDAY WILL BE
STUCK IN THE 20S AND 30S. ON FRIDAY EVENING...THE FRONT WILL STALL
ACROSS WESTERN NEBRASKA TEMPORARILY BEFORE TRACKING SLOWLY EAST
OVERNIGHT. AT THE SAME TIME...A WEAK AREA OF MID LEVEL WARM AIR
ADVECTION WILL LIFT EAST OVER THE FRONT AS A H750 WARM FRONT BEGINS
TO PUSH INTO WESTERN PORTIONS OF THE FORECAST AREA. THERMAL PROFILES
INITIALLY SUPPORT ALL SNOW FRIDAY NIGHT EAST OF THE PANHANDLE AND
FIRST TIER OF COUNTIES FROM MERRIMAN TO HAYES CENTER. HOWEVER...WEST
OF THIS LINE...FCST SOUNDINGS ARE INDICATIVE OF SOME FREEZING
DRIZZLE POTENTIAL. THIS FREEZING DRIZZLE POTENTIAL WILL SPREAD EAST
SATURDAY AS THE WARM FRONT PUSHES EAST ACROSS THE FORECAST AREA. BY
SATURDAY AFTERNOON THE FZDZ THREAT WILL LIE PRIMARILY EAST OF A
AINSWORTH TO TAYLOR LINE. HIGHS SATURDAY WILL RANGE FROM THE MID 20S
IN THE FAR NORTHEASTERN CWA...TO LOWER 40S IN THE EASTERN PANHANDLE
AND FAR SWRN NEBRASKA.
LONG RANGE...SATURDAY NIGHT THROUGH WEDNESDAY...ON SATURDAY
NIGHT...AN EMBEDDED SHORTWAVE WILL LIFT ACROSS THE DAKOTAS AND
NORTHERN NEBRASKA. THE INHERITED FCST DID HAVE A MENTION OF LIGHT
PCPN ACROSS THE NRN THIRD OF THE FORECAST AREA SAT NIGHT AND THIS
WAS RETAINED IN THE CURRENT FORECAST. ON SUNDAY THE UPPER LEVEL
SYSTEM WILL TRACK FROM NORTHERN NEBRASKA AND AND THE CENTRAL DAKOTAS
INTO THE UPPER MISISSIPPI VALLEY. THERE WILL STILL BE A LIMITED
THREAT FOR LIGHT RAIN OR SNOW ACROSS NORTHERN...THEN NORTHEASTERN
NEBRASKA SUNDAY. DECIDED TO LEAVE POPS AT SLIGHT CHANCES FOR
NOW...AS FORCING IS WEAK AND AVAILABLE MOISTURE IS LIMITED WITH THIS
DISTURBANCE. AFTER SUNDAY...TEMPERATURES WILL CONTINUE TO CLIMB INTO
MIDWEEK NEXT WEEK WITH HIGHS TRANSITIONING FROM THE 40S MONDAY...TO
THE 50S TO AROUND 60 TUESDAY...THEN THE 50S FOR WEDNESDAY. THE
PATTERN ALOFT WILL TRANSITION TO MORE OF A ZONAL PATTERN...WHICH
WILL ALLOW WARMER PACIFIC AIR TO INFILTRATE THE CENTRAL PLAINS. ANY
ARCTIC AIR NEXT WEEK...IS EXPECTED TO REMAIN WELL NORTH OF THE
FORECAST AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1126 PM CST WED FEB 10 2016
THE RAP MODEL HAS DONE WELL WITH THE MVFR/IFR CIGS MOVING INTO
NEB THIS EVENING AND IT IS THE BASIS FOR THE FORECAST. THE MODEL
IS SIMILAR TO THE FASTER GFS AND SUGGESTS MOST OF THE FCST AREA
WOULD BE VFR BY 22Z THURSDAY.
LIFR IS POSSIBLE FOG OVERNIGHT ALONG I-80 AND HIGHWAY 61. MVFR/IFR
IS GENERALLY EXPECTED FROM 16Z-20Z.
MVFR CIGS MOVE IN AGAIN THURSDAY EVENING WITH THE NEXT ARCTIC
FRONT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BUTTLER
SHORT TERM...MASEK
LONG TERM...BUTTLER
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1124 PM CST WED FEB 10 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 342 PM CST WED FEB 10 2016
AFTER A SEASONABLY NICE AFTERNOON...EXPECT TEMPERATURES TO
RAPIDLY FALL BACK BELOW FREEZING THIS EVENING AS THE SUN GOES
DOWN...WITH CLOUDS BEGINNING TO ROLL BACK IN ACROSS THE LOCAL
AREA FROM THE NORTHEAST OVERNIGHT. COULD SEE SOME FOG DEVELOPMENT
ON THE LEADING EDGE OF THIS STRATUS...AND OPTED TO INTRODUCE THIS
INTO THE FORECAST AFTER ABOUT MIDNIGHT TONIGHT. WHILE THE BEST
CHANCE FOR THE MORE DENSE FOG IS WEST OF THE LOCAL AREA...THE
LATEST RUN OF THE HRRR IS INDICATING THIS MORE DENSE AREA OF FOG
COULD AT LEAST CREEP IN ON OUR WESTERN COUNTIES TOWARDS
DAYBREAK...AND THIS WILL BE SOMETHING FOR THE EVENING SHIFT TO
MONITOR AS NEW MODEL DATA COMES IN.
OTHERWISE...EXPECT LITTLE SHIFT IN THE OVERALL SYNOPTIC PATTERN
THROUGH THE SHORT TERM PERIODS AS NORTHWESTERLY FLOW ALOFT WILL
CONTINUE WITH A WEAK UPPER LEVEL WAVE MAKING ITS WAY OVER THE TOP
OF THE UPPER LEVEL RIDGE AND TOWARDS THE LOCAL AREA TOMORROW
AFTERNOON. AS THE LOW LEVEL FLOW TURNS MORE EASTERLY AND THEN
SOUTHEASTERLY OVERNIGHT...EXPECT THE FRONTAL BOUNDARY TO OUR EAST
TO INCH BACK ACROSS THE LOCAL AREA...BRINGING SIGNIFICANT LOW
LEVEL STRATUS AND COOLER TEMPERATURES BACK TOWARDS THE REGION
TOMORROW...WITH A MOSTLY CLOUDY DAY AND MORE SEASONAL TEMPERATURES
EXPECTED FOR TOMORROW AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM CST WED FEB 10 2016
MODELS ARE IN GOOD AGREEMENT AT THE START OF THE LONG TERM PERIOD
THURSDAY NIGHT LOOKING AT THE OVERALL PICTURE...UPPER LEVEL NWRLY
FLOW EXPECTED TO REMAIN IN PLACE ACROSS THE REGION. LOW PRESSURE
OVER THE HUDSON BAY AREA KEEPS THE ERN CONUS UNDER BROAD
TROUGHING...WHILE A RIDGE OF HIGH PRESSURE EXTENDS NORTH THROUGH THE
ROCKIES. AT THIS POINT...KEPT THE FORECAST DRY THURS NIGHT AND
FRIDAY...AS MODELS CONTINUE TO KEEP THE BETTER PRECIP CHANCES
ASSOCIATED WITH AN UPPER LEVEL JET STREAK JUST OFF TO THE N/NE OF
THE CWA. THE MAIN STORY THROUGH FRIDAY LIES WITH THE PASSAGE OF A
COLD FRONT...BEING PUSHED SOUTH BY SHORTWAVE ENERGY SWINGING THROUGH
TO THE N/NE. WHILE THE SFC PATTERN STARTS THE PERIOD OUT FAIRLY
RELAXED...THIS FRONT WITH USHER IN NRLY WINDS BY SUNRISE
FRIDAY...GRADUALLY TURNING MORE NERLY THROUGH THE DAY. COLDER AIR
STARTS TO ADVECT INTO THE CWA...AND DID LOWER FORECAST HIGHS FOR
FRIDAY...WITH NEAR 30 NOW IN THE NORTHEAST TO NEAR 40 IN THE SW.
CONFIDENCE IN THIS WEEKEND...MAINLY REGARDING PRECIP
CHANCES/LACK OF...IS NOT HIGH. OVERALL UPPER LEVEL REMAIN LOOKS TO
REMAIN NORTHWESTERLY...BUT THERE IS BETTER POTENTIAL FOR THE CWA TO
BE AFFECTED BY SHORTWAVE ENERGY MOVING THROUGH THE MAIN FLOW. LATE
FRIDAY NIGHT INTO SATURDAY MORNING IS THE FIRST SHOT OF THIS ENERGY
MOVING THROUGH...WITH MODELS ALSO SHOWING THE CWA SITTING ON THE ERN
EDGE OF A 25-30KT LLJ SITTING OVER THE HIGH PLAINS. MODELS HINTING
AT THE POTENTIAL FOR SOME LIGHT PRECIPITATION AFFECTING MAINLY WRN
AND NRN PORTIONS OF THE CWA...WITH FORECAST SOUNDINGS DIFFERING SOME
WITH THE OVERALL THICKNESS OF THE SATURATED LAYER...LEAVING THE
QUESTION WHETHER THERE WOULD BE ANYTHING MEASURABLE...OR IF IT WOULD BE MORE
FZDZ OR FLURRIES. HAVE A 20 POP/SNOW GOING AS WELL AS A SLGT CHANCE
FOR FZDZ. ONLY KEPT THE MENTION GOING THROUGH THE FIRST HALF OF THE
DAY...THOUGH IF YOU BELIEVE THE NAM QPF FIELDS THERE WOULD BE
SOMETHING AROUND ALL DAY SATURDAY. AS FAR AS TEMPERATURES
GO...SATURDAY STILL FORECAST TO BE THE COLDEST DAY OF THE LONG TERM
PERIOD. BY SUNRISE SATURDAY...SFC HIGH PRESSURE IS EXPECTED TO BE
LOCATED OVER NERN IA...WITH ERN PORTIONS OF THE CWA NOT TOO FAR AWAY
FROM DOUBLE DIGIT BELOW ZERO TEMPS AT 850MB. EVEN WITH THE BRUNT OF
THE COLDEST AIR OFF TO OUR EAST...FORECAST HIGHS CURRENTLY RANGE
FROM NEAR 20 IN THE NORTHEAST TO LOWER 30S IN THE SW. LOOKING TO
SUNDAY...THE FORECAST IS DRY...BUT AS MENTIONED ABOVE CONFIDENCE IS
NOT HIGH. MODELS SHOW THE POTENTIAL FOR 1 /PERHAPS 2/ WEAK WAVES TO
MOVE THROUGH THE PLAINS THROUGH SUNDAY NIGHT...JUST SOME DIFFERENCES
IN LOCATION. WILL SEE HOW THINGS TREND BEFORE INSERTING POPS.
EXPECTING TO SEE REBOUNDING TEMPS FOR SUNDAY AS THAT COLDER AIR
PUSHES EAST AND WARMER TEMPS START TO BUILD IN...WITH 40S CURRENTLY
FORECAST FOR MOST OF THE CWA.
THROUGH THE FIRST HALF OF THE NEXT WORK WEEK...THE FORECAST REMAINS
DRY...WITH MODELS IN PRETTY GOOD AGREEMENT SHOWING BROAD UPPER LEVEL
RIDGING TAKING OVER THE WRN CONUS AND GRADUALLY BUILDING EAST. NICE
WARM UP CURRENTLY GOING IN THE FORECAST...WITH 50S FORECAST FOR
TUE/WED.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1120 PM CST WED FEB 10 2016
STRATUS CONTINUES TO PUSH SOUTH INTO THE TERMINAL AREAS IN THE
NEXT FEW HOURS. EXPECT THE LOWEST CEILINGS TO BE A FEW HOURS
EITHER SIDE OF SUNRISE. CEILINGS SHOULD INCREASE A LITTLE DURING
THE DAY...BUT THE STRATUS SHOULD LINGER THROUGH MUCH OF THE
PERIOD. DUE TO SNOW MELT TODAY...LIGHT WINDS AND THE EDGE OF THE
STRATUS AROUND THE AREA...THERE COULD BE SOME FOG. THE LOCATION
AND HOW DENSE IT GETS IS STILL IN QUESTION AT THIS TIME.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...ROSSI
LONG TERM...ADP
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
302 PM EST THU FEB 11 2016
.SYNOPSIS...
LAKE EFFECT SNOW WILL BE HEAVY AT TIMES THROUGH TONIGHT IN PARTS
OF CENTRAL NEW YORK...GENERALLY SOUTHEAST OF LAKE ONTARIO.
SCATTERED SNOW SHOWERS AND FLURRIES WILL OCCUR ELSEWHERE WITH
LIGHT ACCUMULATIONS. A STRONG ARCTIC FRONT WILL DROP THROUGH THE
REGION LATE FRIDAY...BRINGING THE COLDEST AIR MASS SINCE LAST
WINTER. WIND CHILLS WILL BE DANGEROUSLY LOW...WELL BELOW
ZERO...SATURDAY THROUGH SATURDAY NIGHT. A MODERATING TREND IS
EXPECTED EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATED AT 1130 AM... MAIN LAKE EFFECT BANDS CONTINUE E-SE OF LAKE
ONTARIO ON ABOUT A 290 FLOW LATE THIS MORNING WITH NUMEROUS
SECONDARY WEAKER BANDS FARTHER SOUTH EXTENDING INTO NORTHERN PA.
BANDS STILL APPEAR TO BE SHIFTING SLOWLY SOUTH AND ARE NEAR THE
THRUWAY LATE THIS MORNING WITH STILL THE POTENTIAL FOR SOME HEAVY
BANDS TO GET INTO THE CITIES OF SYRACUSE AND UTICA AT SOME POINT
THIS AFTERNOON. STILL EXPECTING SEVERAL INCHES THIS AFTERNOON
FROM NORTHERN ONONDAGA COUNTY EAST TO WEST CENTRAL ONEIDA COUNTY
WITH LESS TO THE SOUTH. ATMOSPHERE UPSTREAM FROM THESE BANDS IS
BECOMING INCREASINGLY DRY AND NO GOOD CONNECTION WITH LAKE HURON /
GEORGIAN BAY CAN BE SEEN ON LATEST VISIBLE IMAGERY. ALSO DENDRITIC
SNOW GROWTH POTENTIAL IS NOT OPTIMAL AS THE ATMOSPHERE HAS BECOME
COLD ENOUGH SO THAT ONLY A SHALLOW LAYER ABOVE -20 C EXISTS BELOW
900 MB.
WILL KEEP CURRENT WARNINGS AND ADVISORIES GOING THROUGH THIS
AFTERNOON AS SNOW SHOWERS AND BLOWING SNOW WILL MAKE FOR HAZARDOUS
TRAVEL... ALTHOUGH WARNING TYPE ACCUMULATIONS LOOK TO REMAIN JUST
NORTH OF THE CITY OF SYRACUSE THROUGH TODAY... WITH JUST ANOTHER
COUPLE OF INCHES IN THE ADVISORY AREAS TO THE SOUTH. TEMPERATURES
ARE ONLY EXPECTED TO RISE A FEW DEGREES FROM CURRENT LEVELS WITH
TEENS IN MOST AREAS TO NEAR 20 IN THE LOWER ELEVATIONS OF NORTHERN
PA. PREVIOUS DISCUSSION IS BELOW.
315 AM UPDATE...
WANTED TO SEND OUT AN "EARLY" UPDATE TO REFLECT ON THE CURRENT
SITUATION REGARDING OUR LAKE EFFECT EVENT. WILL SEND OUT A
SEPARATE AFD FOR THE SHORT TERM PERIOD TO GO OVER THE DANGEROUS
COLD OVER THE WEEKEND. FIRST THINGS FIRST, THE LAKE EFFECT. SEE
OUR WEBSITE FOR OUR LATEST SNOWFALL MAP THAT I JUST POSTED.
WARNINGS AND ADVISORIES WILL REMAIN IN PLACE. I DID SHIFT THE
HEAVIER AXIS OF SNOW FARTHER NORTH, TO REFLECT RADAR TRENDS FROM
YESTERDAY EVENING THROUGH NOW. THE CHANGE WILL INCREASE AMOUNTS IN
WEST CENTRAL ONEIDA COUNTY QUITE A BIT, WHILE DROPPING OFF
SHARPLY TOWARD THE CITY OF UTICA. I KEPT NORTHERN ONONDAGA IN THE
HIGHER AMOUNTS AS WELL, ALTHOUGH THEY WILL PROBABLY END UP BEING
LOWER OVERALL THAN WEST CENTRAL ONEIDA. THE HIGHER TOTALS ACROSS
NORTHERN ONONDAGA COUNTY IS A REFLECTION OF WHAT WE EXPECT TO
COME, NOT UNDERSTANDING WE HAVEN`T SEE MUCH SNOW HERE YET. WHILE
THE FORECAST GOING FORECAST IS LARGELY UNCHANGED FROM THIS POINT
FORWARD, WE HAVEN`T SEE MUCH SNOW AT ALL FROM THE NEAR THE CITY
OF SYRACUSE SOUTH. THUS I HAVE ADJUSTED TOTALS DOWN ACROSS
SOUTHERN ONONDAGA/MADISON COUNTIES, ALONG WITH NORTHERN
CORTLAND/CHENANGO/OTSEGO.
WHILE THE BAND HAS BEEN MAINLY NORTH OF KSYR AND HAS EVEN WAVERED
BACK INTO NORTHERN ONEIDA, CONFIDENCE IS HIGH THAT THE BAND WILL
SINK SOUTH BETWEEN 09Z AND 12Z. THE LATEST HRRR AND RAP SOUNDINGS
SHOW A MEAN WIND OF 275 NOW, ABRUPTLY SHIFTING TOWARD 290 BY 12Z,
THEN LOCKING IN FOR THE REST OF THE DAY. KBUF RADAR SHOWS THE
WESTERN SIDE OF THE BAND NEAR KROC IS ALREADY SHOWING SIGNS OF
THIS CHANGE AND WILL FOLLOW. SO WHILE THE EVENT HAS PLAYED OUT
WELL THUS FAR ACROSS WEST CENTRAL ONEIDA COUNTY, MANY IN METRO
SYRACUSE AND ALONG THE THRUWAY MAY BE WONDERING WHAT LAKE SNOWS?
DON`T LET YOUR GUARD DOWN YET AS HEAVIER SNOWS WILL SHIFT SOUTH
TODAY. WITH INVERSION HEIGHTS GRADUALLY LOWERING TOWARD 5KFT BY
LATE AFTERNOON, THE OVERALL INTENSITY WILL BE HIGHEST THIS
MORNING, THEN A GRADUAL WEAKENING TREND INTO EARLY TONIGHT.
SNOWFALL RATES THROUGH MID MORNING WILL STILL BE IN THE 1 TO 2"+
RANGE. THE FLOW REMAINS AROUND 290-300 THROUGH 06Z TONIGHT, BEFORE
THE FLOW BACKS ENOUGH TOWARD THE SOUTHWEST TO LIFT THE BAND OUT OF
OUR AREA TOWARD DAYBREAK FRIDAY. IN ALL A WIDESPREAD, LONG
DURATION 6"+ LOOKS GOOD ACROSS MUCH OF CENTRAL NY, WITH CLOSER TO
1 1/2 FEET OVER WESTERN ONEIDA COUNTY. I CONTINUE TO MENTION BLOW
AND DRIFTING SNOW WITHIN AND NEAR THE SNOW BANDS THEMSELVES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
4 AM UPDATE...
OVERVIEW...SNOW SQUALLS LIKELY FRIDAY NIGHT ALONG AN ARCTIC FRONT
THAT WILL DELIVER BRUTAL COLD SATURDAY AND SATURDAY NIGHT, WHICH
WILL RIVAL WHAT WE SAW LAST FEBRUARY.
FRIDAY/FRIDAY NIGHT....MOST OF FRIDAY WILL BE QUIET WITH A
SOUTHWEST FLOW AHEAD OF AN ARCTIC FRONT. THIS FLOW WILL KEEP MOST
OF THE AREA DRY THROUGH THE DAYLIGHT HOURS. FRIDAY EVENING THE
ARCTIC FRONT WILL CROSS THE AREA BETWEEN 0Z AND 06Z SATURDAY. SNOW
SQUALLS LOOK LIKELY, WITH THE POTENTIAL FOR POOR VISIBILITY AND
SNOWFALL RATES OF MORE THAN AN INCH PER HOUR. MODEL SOUNDINGS SHOW
STEEP LAPSE RATES OF MORE THAN 8.0 C/KM UP THROUGH 650 MB! IN
ADDITION STRONG OMEGA (LIFT/RISING AIR IN THE ATMOSPHERE) IS FOUND
WITH PLENTY OF MOISTURE RIGHT IN THE SNOW GROWTH REGION. THINK BIG
FLAKES, HIGH EFFICIENCY OF ACCUMULATING SNOWS. WILL ADD CHANCE OF
HEAVY SNOW FOR THE FRIDAY EVENING FORECAST. SNOWFALL AMOUNTS OF A
FEW INCHES LIKELY BUT AGAIN IT WILL BE THE RATE OF FALL WHICH WILL
CAUSE POOR VISIBILITIES AND DANGEROUS ROADS.
SATURDAY/SATURDAY NIGHT...BRUTAL COLD. 850 TEMPS FALL TO BETWEEN
-28C AND -30C! "OFFICIAL" HIGHS SATURDAY WILL BE IN THE TEENS AT
MIDNIGHT FRIDAY NIGHT, WITH TEMPS FALLING INTO THE SINGLE DIGITS
BY SATURDAY AFTERNOON. SOME AREAS WILL LIKELY DROP BELOW ZERO FOR
TEMPS SATURDAY AFTERNOON, ESPECIALLY IN NY STATE! THIS ALONE IS
COLD BUT A PRESSURE GRADIENT BETWEEN AN OCEAN STORM AND HIGH
PRESSURE OVER THE MIDWEST WILL PRODUCE ENOUGH WIND FOR WIND CHILL
READINGS BETWEEN -10 AND -30. WE WILL CONTINUE TO HIGHLIGHT THE
HIGH CONFIDENCE FOR EXTREME COLD AND DANGEROUS WIND CHILLS IN OUR
HWO, ON SOCIAL MEDIA, AND IN OUR ONLINE BRIEFING PACKAGE FOUND AT
WEATHER.GOV/BGM UNDER WEATHER HAZARD BRIEFING AT THE BOTTOM OF THE
PAGE. LOWS SATURDAY NIGHT WILL BE BELOW ZERO EVERYWHERE, WITH -20
READINGS POSSIBLE IN OUR COLDER SPOTS. IMPRESSIVE COLD AND THE
ONLY SILVER LINING IS THE FACT IT WON`T LAST LONG. SEE BELOW FOR
MORE ON MILDER WEATHER NEXT WEEK.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
245 PM THU UPDATE...
WE START OFF WELL SUBZERO DAWN SUNDAY. WINDS WILL BE
SIGNIFICANTLY LESS THAN SATURDAY...YET STILL ENOUGH TO YIELD
DANGEROUSLY LOW WIND CHILLS FOR AT LEAST THE FIRST HALF OF THE DAY
BECAUSE IT WILL TAKE UNTIL LATE SUNDAY- SUNDAY NIGHT FOR HIGH
PRESSURE TO ACTUALLY BUILD IN. LAKE MOISTURE STILL TRAPPED UNDER
THE DEVELOPING SUBSIDENCE INVERSION WILL ALSO CONTINUE SCATTERED
SNOW SHOWERS AND FLURRIES FROM STEUBEN COUNTY THROUGH THE FINGER
LAKES TO SYRACUSE REGIONS...BUT WITH ONLY LIGHT DRY FLUFFY
ACCUMULATIONS. HIGHS WILL ONLY BE IN THE SINGLE DIGITS TO AROUND
12 DEGREES.
BUSY PATTERN COMES TOGETHER FOR MONDAY THROUGH WEDNESDAY. SHARP
TROUGH FROM THIS WEEKEND LIFTS OUT...ONLY FOR MEAN UPPER TROUGH
POSITIONING TO RETROGRADE SLIGHTLY WEST AS A NEW ONE DIGS INTO THE
GREAT LAKES REGION. PHASING OF NORTHERN AND SOUTHERN STREAMS LOOKS
LIKELY TO PRODUCE A LOW PRESSURE SYSTEM SOMEWHERE IN THE
SOUTHEAST...WHICH THEN DEEPENS WHILE HEADING NORTHEAST. WITH
RETROGRADED TROUGH...WARMER AIR WILL BE ABLE TO ADVECT IN AS THE
SYSTEM APPROACHES. THE DEVIL IS IN THE DETAILS...AND WHILE THE
MODELS AGREE ON EXISTENCE OF THE SYSTEM...THEY HAVE BEEN
INCONSISTENT ON ITS TRACK AND AMOUNT OF WARM AIR RUN-TO-RUN AND
MODEL-TO-MODEL. ONE THING THAT APPEARS MISSING IS HIGH PRESSURE IN
THE NORTHEAST FOR ANCHORING THE COLD AIR...SO THE WARMER TREND IN
LATEST GUIDANCE MAKES SENSE. ALL WE CAN SAY AT THIS POINT IS A
FAIR AMOUNT OF PRECIPITATION IS LOOKING PROBABLE ESPECIALLY MONDAY
NIGHT THROUGH TUESDAY NIGHT...BUT PRECIPITATION TYPE IS VERY
QUESTIONABLE. STAY TUNED.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
LAKE EFFECT BANDS WITH IFR TO BELOW ALT MINS FOR VIS WILL
CONTINUE TO IMPACT KSYR AND KRME THIS AFTERNOON...PERSISTING INTO
EVENING FOR KSYR BEFORE LIFTING BACK BRIEFLY INTO KRME LATE
TONIGHT BEFORE ENDING. BLSN WILL ALSO HAMPER VIS THIS AFTERNOON
UNTIL THE WNW WINDS DIMINISH THIS EVENING...AND THEN BACK
SOUTHWESTERLY FRIDAY MORNING /VRB TO SE KRME/. FURTHER
SOUTH...THINNER BANDS WILL BRIEFLY VISIT THE OTHER NY
TERMINALS...INCLUDING INTERMITTENT IFR VIS FOR KBGM THROUGH 20Z
AND MVFR VIS FOR KITH. KAVP AND KELM WILL GET FLURRIES BUT LIKELY
NON-RESTRICTING. EXCEPT FOR THE LINGERING KSYR-KRME ISSUES
MENTIONED ABOVE...ALL TERMINALS GO VFR TONIGHT THROUGH FRIDAY
MORNING.
.OUTLOOK...
FRI AFTN-NGT...VFR UNTIL STRONG ARCTIC FRONT BLASTS THROUGH WITH
A PROBABLE LOW VIS SNOW SQUALL ROUGHLY 01Z SAT NW TO 07Z SAT SE.
SAT...OCCASIONAL RESTRICTIONS FROM SCT -SHSN AND GUSTY WINDS/BLSN.
SAT NGT-SUN...LAKE EFFECT SCT -SHSN AND ASSOCIATED BRIEF
RESTRICTIONS KSYR AND PERHAPS KITH-KELM.
MON-TUE...RESTRICTIONS IN POTENTIAL SNOW-TO-MIX AS AN EAST COAST
SYSTEM MOVES THROUGH...BEST CHANCE MON NGT-TUE.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ016-017-044>046.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST FRIDAY FOR NYZ009-018-
036-037.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN/MSE
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1253 PM EST THU FEB 11 2016
.SYNOPSIS...
LAKE EFFECT SNOW WILL BE HEAVY AT TIMES THROUGH TONIGHT IN PARTS
OF CENTRAL NEW YORK...GENERALLY SOUTHEAST OF LAKE ONTARIO.
SCATTERED SNOW SHOWERS AND FLURRIES WILL OCCUR ELSEWHERE WITH
LIGHT ACCUMULATIONS. A STRONG ARCTIC FRONT WILL DROP THROUGH THE
REGION LATE FRIDAY...BRINGING THE COLDEST AIR MASS SINCE LAST
WINTER. WIND CHILLS WILL BE DANGEROUSLY LOW...WELL BELOW
ZERO...SATURDAY THROUGH SATURDAY NIGHT. A MODERATING TREND IS
EXPECTED EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATED AT 1130 AM... MAIN LAKE EFFECT BANDS CONTINUE E-SE OF LAKE
ONTARIO ON ABOUT A 290 FLOW LATE THIS MORNING WITH NUMEROUS
SECONDARY WEAKER BANDS FARTHER SOUTH EXTENDING INTO NORTHERN PA.
BANDS STILL APPEAR TO BE SHIFTING SLOWLY SOUTH AND ARE NEAR THE
THRUWAY LATE THIS MORNING WITH STILL THE POTENTIAL FOR SOME HEAVY
BANDS TO GET INTO THE CITIES OF SYRACUSE AND UTICA AT SOME POINT
THIS AFTERNOON. STILL EXPECTING SEVERAL INCHES THIS AFTERNOON
FROM NORTHERN ONONDAGA COUNTY EAST TO WEST CENTRAL ONEIDA COUNTY
WITH LESS TO THE SOUTH. ATMOSPHERE UPSTREAM FROM THESE BANDS IS
BECOMING INCREASINGLY DRY AND NO GOOD CONNECTION WITH LAKE HURON /
GEORGIAN BAY CAN BE SEEN ON LATEST VISIBLE IMAGERY. ALSO DENDRITIC
SNOW GROWTH POTENTIAL IS NOT OPTIMAL AS THE ATMOSPHERE HAS BECOME
COLD ENOUGH SO THAT ONLY A SHALLOW LAYER ABOVE -20 C EXISTS BELOW
900 MB.
WILL KEEP CURRENT WARNINGS AND ADVISORIES GOING THROUGH THIS
AFTERNOON AS SNOW SHOWERS AND BLOWING SNOW WILL MAKE FOR HAZARDOUS
TRAVEL... ALTHOUGH WARNING TYPE ACCUMULATIONS LOOK TO REMAIN JUST
NORTH OF THE CITY OF SYRACUSE THROUGH TODAY... WITH JUST ANOTHER
COUPLE OF INCHES IN THE ADVISORY AREAS TO THE SOUTH. TEMPERATURES
ARE ONLY EXPECTED TO RISE A FEW DEGREES FROM CURRENT LEVELS WITH
TEENS IN MOST AREAS TO NEAR 20 IN THE LOWER ELEVATIONS OF NORTHERN
PA. PREVIOUS DISCUSSION IS BELOW.
315 AM UPDATE...
WANTED TO SEND OUT AN "EARLY" UPDATE TO REFLECT ON THE CURRENT
SITUATION REGARDING OUR LAKE EFFECT EVENT. WILL SEND OUT A
SEPARATE AFD FOR THE SHORT TERM PERIOD TO GO OVER THE DANGEROUS
COLD OVER THE WEEKEND. FIRST THINGS FIRST, THE LAKE EFFECT. SEE
OUR WEBSITE FOR OUR LATEST SNOWFALL MAP THAT I JUST POSTED.
WARNINGS AND ADVISORIES WILL REMAIN IN PLACE. I DID SHIFT THE
HEAVIER AXIS OF SNOW FARTHER NORTH, TO REFLECT RADAR TRENDS FROM
YESTERDAY EVENING THROUGH NOW. THE CHANGE WILL INCREASE AMOUNTS IN
WEST CENTRAL ONEIDA COUNTY QUITE A BIT, WHILE DROPPING OFF
SHARPLY TOWARD THE CITY OF UTICA. I KEPT NORTHERN ONONDAGA IN THE
HIGHER AMOUNTS AS WELL, ALTHOUGH THEY WILL PROBABLY END UP BEING
LOWER OVERALL THAN WEST CENTRAL ONEIDA. THE HIGHER TOTALS ACROSS
NORTHERN ONONDAGA COUNTY IS A REFLECTION OF WHAT WE EXPECT TO
COME, NOT UNDERSTANDING WE HAVEN`T SEE MUCH SNOW HERE YET. WHILE
THE FORECAST GOING FORECAST IS LARGELY UNCHANGED FROM THIS POINT
FORWARD, WE HAVEN`T SEE MUCH SNOW AT ALL FROM THE NEAR THE CITY
OF SYRACUSE SOUTH. THUS I HAVE ADJUSTED TOTALS DOWN ACROSS
SOUTHERN ONONDAGA/MADISON COUNTIES, ALONG WITH NORTHERN
CORTLAND/CHENANGO/OTSEGO.
WHILE THE BAND HAS BEEN MAINLY NORTH OF KSYR AND HAS EVEN WAVERED
BACK INTO NORTHERN ONEIDA, CONFIDENCE IS HIGH THAT THE BAND WILL
SINK SOUTH BETWEEN 09Z AND 12Z. THE LATEST HRRR AND RAP SOUNDINGS
SHOW A MEAN WIND OF 275 NOW, ABRUPTLY SHIFTING TOWARD 290 BY 12Z,
THEN LOCKING IN FOR THE REST OF THE DAY. KBUF RADAR SHOWS THE
WESTERN SIDE OF THE BAND NEAR KROC IS ALREADY SHOWING SIGNS OF
THIS CHANGE AND WILL FOLLOW. SO WHILE THE EVENT HAS PLAYED OUT
WELL THUS FAR ACROSS WEST CENTRAL ONEIDA COUNTY, MANY IN METRO
SYRACUSE AND ALONG THE THRUWAY MAY BE WONDERING WHAT LAKE SNOWS?
DON`T LET YOUR GUARD DOWN YET AS HEAVIER SNOWS WILL SHIFT SOUTH
TODAY. WITH INVERSION HEIGHTS GRADUALLY LOWERING TOWARD 5KFT BY
LATE AFTERNOON, THE OVERALL INTENSITY WILL BE HIGHEST THIS
MORNING, THEN A GRADUAL WEAKENING TREND INTO EARLY TONIGHT.
SNOWFALL RATES THROUGH MID MORNING WILL STILL BE IN THE 1 TO 2"+
RANGE. THE FLOW REMAINS AROUND 290-300 THROUGH 06Z TONIGHT, BEFORE
THE FLOW BACKS ENOUGH TOWARD THE SOUTHWEST TO LIFT THE BAND OUT OF
OUR AREA TOWARD DAYBREAK FRIDAY. IN ALL A WIDESPREAD, LONG
DURATION 6"+ LOOKS GOOD ACROSS MUCH OF CENTRAL NY, WITH CLOSER TO
1 1/2 FEET OVER WESTERN ONEIDA COUNTY. I CONTINUE TO MENTION BLOW
AND DRIFTING SNOW WITHIN AND NEAR THE SNOW BANDS THEMSELVES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
4 AM UPDATE...
OVERVIEW...SNOW SQUALLS LIKELY FRIDAY NIGHT ALONG AN ARCTIC FRONT
THAT WILL DELIVER BRUTAL COLD SATURDAY AND SATURDAY NIGHT, WHICH
WILL RIVAL WHAT WE SAW LAST FEBRUARY.
FRIDAY/FRIDAY NIGHT....MOST OF FRIDAY WILL BE QUIET WITH A
SOUTHWEST FLOW AHEAD OF AN ARCTIC FRONT. THIS FLOW WILL KEEP MOST
OF THE AREA DRY THROUGH THE DAYLIGHT HOURS. FRIDAY EVENING THE
ARCTIC FRONT WILL CROSS THE AREA BETWEEN 0Z AND 06Z SATURDAY. SNOW
SQUALLS LOOK LIKELY, WITH THE POTENTIAL FOR POOR VISIBILITY AND
SNOWFALL RATES OF MORE THAN AN INCH PER HOUR. MODEL SOUNDINGS SHOW
STEEP LAPSE RATES OF MORE THAN 8.0 C/KM UP THROUGH 650 MB! IN
ADDITION STRONG OMEGA (LIFT/RISING AIR IN THE ATMOSPHERE) IS FOUND
WITH PLENTY OF MOISTURE RIGHT IN THE SNOW GROWTH REGION. THINK BIG
FLAKES, HIGH EFFICIENCY OF ACCUMULATING SNOWS. WILL ADD CHANCE OF
HEAVY SNOW FOR THE FRIDAY EVENING FORECAST. SNOWFALL AMOUNTS OF A
FEW INCHES LIKELY BUT AGAIN IT WILL BE THE RATE OF FALL WHICH WILL
CAUSE POOR VISIBILITIES AND DANGEROUS ROADS.
SATURDAY/SATURDAY NIGHT...BRUTAL COLD. 850 TEMPS FALL TO BETWEEN
-28C AND -30C! "OFFICIAL" HIGHS SATURDAY WILL BE IN THE TEENS AT
MIDNIGHT FRIDAY NIGHT, WITH TEMPS FALLING INTO THE SINGLE DIGITS
BY SATURDAY AFTERNOON. SOME AREAS WILL LIKELY DROP BELOW ZERO FOR
TEMPS SATURDAY AFTERNOON, ESPECIALLY IN NY STATE! THIS ALONE IS
COLD BUT A PRESSURE GRADIENT BETWEEN AN OCEAN STORM AND HIGH
PRESSURE OVER THE MIDWEST WILL PRODUCE ENOUGH WIND FOR WIND CHILL
READINGS BETWEEN -10 AND -30. WE WILL CONTINUE TO HIGHLIGHT THE
HIGH CONFIDENCE FOR EXTREME COLD AND DANGEROUS WIND CHILLS IN OUR
HWO, ON SOCIAL MEDIA, AND IN OUR ONLINE BRIEFING PACKAGE FOUND AT
WEATHER.GOV/BGM UNDER WEATHER HAZARD BRIEFING AT THE BOTTOM OF THE
PAGE. LOWS SATURDAY NIGHT WILL BE BELOW ZERO EVERYWHERE, WITH -20
READINGS POSSIBLE IN OUR COLDER SPOTS. IMPRESSIVE COLD AND THE
ONLY SILVER LINING IS THE FACT IT WON`T LAST LONG. SEE BELOW FOR
MORE ON MILDER WEATHER NEXT WEEK.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
430 PM UPDATE...
ONLY SOME MODERATION IN TEMPERATURES EXPECTED SUNDAY AS ARCTIC
HIGH SLIDES EAST RIGHT OVER THE AREA BY LATE DAY. WINDS WILL BE
SIGNIFICANTLY LESS...YET WE START THE DAY WITH SUBZERO
TEMPERATURES SO VERY COLD ANYWAYS. STILL EXPECT SOME LAKE EFFECT,
THOUGH THIS WILL TEND TO BE DIMINISHING THROUGH THE DAY HAS THE
HIGH MOVES IN. HIGHS LOOK TO RANGE FROM THE SINGLE DIGITS THROUGH
MUCH OF THE CATSKILLS NORTH TO THE TUG HILL WITH LOW TO MID TEENS
ELSEWHERE.
PATTERN WILL BE PROGRESSIVE ENOUGH FOR CORE OF ARCTIC AIR TO MOVE
OUT EARLY NEXT WEEK WITH MORE SIGNIFICANT MODERATION BACK TO AT
LEAST SEASONAL. MODELS INDICATE THE NEXT UPPER TROUGH MOVING INTO
THE EAST WITH LOW PRESSURE DEVELOPMENT BUT THERE IS MODEL
DISAGREEMENT ON TIMING, TRACK, AND INTENSITY. FOR NOW, INDICATE
CHANCE OF SNOW IN GRIDS FOR MONDAY THROUGH WEDNESDAY BUT THERE IS A
CHANCE LOW COULD TRACK FAR ENOUGH WEST TO BRING RAIN TO SOME AREAS
AS EARLY AS TUESDAY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
LAKE EFFECT BANDS WITH IFR TO BELOW ALT MINS FOR VIS WILL
CONTINUE TO IMPACT KSYR AND KRME THIS AFTERNOON...PERSISTING INTO
EVENING FOR KSYR BEFORE LIFTING BACK BRIEFLY INTO KRME LATE
TONIGHT BEFORE ENDING. BLSN WILL ALSO HAMPER VIS THIS AFTERNOON
UNTIL THE WNW WINDS DIMINISH THIS EVENING...AND THEN BACK
SOUTHWESTERLY FRIDAY MORNING /VRB TO SE KRME/. FURTHER
SOUTH...THINNER BANDS WILL BRIEFLY VISIT THE OTHER NY
TERMINALS...INCLUDING INTERMITTENT IFR VIS FOR KBGM THROUGH 20Z
AND MVFR VIS FOR KITH. KAVP AND KELM WILL GET FLURRIES BUT LIKELY
NON-RESTRICTING. EXCEPT FOR THE LINGERING KSYR-KRME ISSUES
MENTIONED ABOVE...ALL TERMINALS GO VFR TONIGHT THROUGH FRIDAY
MORNING.
.OUTLOOK...
FRI AFTN-NGT...VFR UNTIL STRONG ARCTIC FRONT BLASTS THROUGH WITH
A PROBABLE LOW VIS SNOW SQUALL ROUGHLY 01Z SAT NW TO 07Z SAT SE.
SAT...OCCASIONAL RESTRICTIONS FROM SCT -SHSN AND GUSTY WINDS/BLSN.
SAT NGT-SUN...LAKE EFFECT SCT -SHSN AND ASSOCIATED BRIEF
RESTRICTIONS KSYR AND PERHAPS KITH-KELM.
MON-TUE...RESTRICTIONS IN POTENTIAL SNOW AS AN EAST COAST SYSTEM
MOVES THROUGH...BEST CHANCE MON NGT-TUE.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ016-017-044>046.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST FRIDAY FOR NYZ009-018-
036-037.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN/MSE
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1152 AM EST THU FEB 11 2016
.SYNOPSIS...
LAKE EFFECT SNOW WILL BE HEAVY AT TIMES THROUGH TONIGHT IN PARTS
OF CENTRAL NEW YORK...GENERALLY SOUTHEAST OF LAKE ONTARIO.
SCATTERED SNOW SHOWERS AND FLURRIES WILL OCCUR ELSEWHERE WITH
LIGHT ACCUMULATIONS. A STRONG ARCTIC FRONT WILL DROP THROUGH THE
REGION LATE FRIDAY...BRINGING THE COLDEST AIR MASS SINCE LAST
WINTER. WIND CHILLS WILL BE DANGEROUSLY LOW...WELL BELOW
ZERO...SATURDAY THROUGH SATURDAY NIGHT. A MODERATING TREND IS
EXPECTED EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATED AT 1130 AM... MAIN LAKE EFFECT BANDS CONTINUE E-SE OF LAKE
ONTARIO ON ABOUT A 290 FLOW LATE THIS MORNING WITH NUMEROUS
SECONDARY WEAKER BANDS FARTHER SOUTH EXTENDING INTO NORTHERN PA.
BANDS STILL APPEAR TO BE SHIFTING SLOWLY SOUTH AND ARE NEAR THE
THRUWAY LATE THIS MORNING WITH STILL THE POTENTIAL FOR SOME HEAVY
BANDS TO GET INTO THE CITIES OF SYRACUSE AND UTICA AT SOME POINT
THIS AFTERNOON. STILL EXPECTING SEVERAL INCHES THIS AFTERNOON
FROM NORTHERN ONONDAGA COUNTY EAST TO WEST CENTRAL ONEIDA COUNTY
WITH LESS TO THE SOUTH. ATMOSPHERE UPSTREAM FROM THESE BANDS IS
BECOMING INCREASINGLY DRY AND NO GOOD CONNECTION WITH LAKE HURON /
GEORGIAN BAY CAN BE SEEN ON LATEST VISIBLE IMAGERY. ALSO DENDRITIC
SNOW GROWTH POTENTIAL IS NOT OPTIMAL AS THE ATMOSPHERE HAS BECOME
COLD ENOUGH SO THAT ONLY A SHALLOW LAYER ABOVE -20 C EXISTS BELOW
900 MB.
WILL KEEP CURRENT WARNINGS AND ADVISORIES GOING THROUGH THIS
AFTERNOON AS SNOW SHOWERS AND BLOWING SNOW WILL MAKE FOR HAZARDOUS
TRAVEL... ALTHOUGH WARNING TYPE ACCUMULATIONS LOOK TO REMAIN JUST
NORTH OF THE CITY OF SYRACUSE THROUGH TODAY... WITH JUST ANOTHER
COUPLE OF INCHES IN THE ADVISORY AREAS TO THE SOUTH. TEMPERATURES
ARE ONLY EXPECTED TO RISE A FEW DEGREES FROM CURRENT LEVELS WITH
TEENS IN MOST AREAS TO NEAR 20 IN THE LOWER ELEVATIONS OF NORTHERN
PA. PREVIOUS DISCUSSION IS BELOW.
315 AM UPDATE...
WANTED TO SEND OUT AN "EARLY" UPDATE TO REFLECT ON THE CURRENT
SITUATION REGARDING OUR LAKE EFFECT EVENT. WILL SEND OUT A
SEPARATE AFD FOR THE SHORT TERM PERIOD TO GO OVER THE DANGEROUS
COLD OVER THE WEEKEND. FIRST THINGS FIRST, THE LAKE EFFECT. SEE
OUR WEBSITE FOR OUR LATEST SNOWFALL MAP THAT I JUST POSTED.
WARNINGS AND ADVISORIES WILL REMAIN IN PLACE. I DID SHIFT THE
HEAVIER AXIS OF SNOW FARTHER NORTH, TO REFLECT RADAR TRENDS FROM
YESTERDAY EVENING THROUGH NOW. THE CHANGE WILL INCREASE AMOUNTS IN
WEST CENTRAL ONEIDA COUNTY QUITE A BIT, WHILE DROPPING OFF
SHARPLY TOWARD THE CITY OF UTICA. I KEPT NORTHERN ONONDAGA IN THE
HIGHER AMOUNTS AS WELL, ALTHOUGH THEY WILL PROBABLY END UP BEING
LOWER OVERALL THAN WEST CENTRAL ONEIDA. THE HIGHER TOTALS ACROSS
NORTHERN ONONDAGA COUNTY IS A REFLECTION OF WHAT WE EXPECT TO
COME, NOT UNDERSTANDING WE HAVEN`T SEE MUCH SNOW HERE YET. WHILE
THE FORECAST GOING FORECAST IS LARGELY UNCHANGED FROM THIS POINT
FORWARD, WE HAVEN`T SEE MUCH SNOW AT ALL FROM THE NEAR THE CITY
OF SYRACUSE SOUTH. THUS I HAVE ADJUSTED TOTALS DOWN ACROSS
SOUTHERN ONONDAGA/MADISON COUNTIES, ALONG WITH NORTHERN
CORTLAND/CHENANGO/OTSEGO.
WHILE THE BAND HAS BEEN MAINLY NORTH OF KSYR AND HAS EVEN WAVERED
BACK INTO NORTHERN ONEIDA, CONFIDENCE IS HIGH THAT THE BAND WILL
SINK SOUTH BETWEEN 09Z AND 12Z. THE LATEST HRRR AND RAP SOUNDINGS
SHOW A MEAN WIND OF 275 NOW, ABRUPTLY SHIFTING TOWARD 290 BY 12Z,
THEN LOCKING IN FOR THE REST OF THE DAY. KBUF RADAR SHOWS THE
WESTERN SIDE OF THE BAND NEAR KROC IS ALREADY SHOWING SIGNS OF
THIS CHANGE AND WILL FOLLOW. SO WHILE THE EVENT HAS PLAYED OUT
WELL THUS FAR ACROSS WEST CENTRAL ONEIDA COUNTY, MANY IN METRO
SYRACUSE AND ALONG THE THRUWAY MAY BE WONDERING WHAT LAKE SNOWS?
DON`T LET YOUR GUARD DOWN YET AS HEAVIER SNOWS WILL SHIFT SOUTH
TODAY. WITH INVERSION HEIGHTS GRADUALLY LOWERING TOWARD 5KFT BY
LATE AFTERNOON, THE OVERALL INTENSITY WILL BE HIGHEST THIS
MORNING, THEN A GRADUAL WEAKENING TREND INTO EARLY TONIGHT.
SNOWFALL RATES THROUGH MID MORNING WILL STILL BE IN THE 1 TO 2"+
RANGE. THE FLOW REMAINS AROUND 290-300 THROUGH 06Z TONIGHT, BEFORE
THE FLOW BACKS ENOUGH TOWARD THE SOUTHWEST TO LIFT THE BAND OUT OF
OUR AREA TOWARD DAYBREAK FRIDAY. IN ALL A WIDESPREAD, LONG
DURATION 6"+ LOOKS GOOD ACROSS MUCH OF CENTRAL NY, WITH CLOSER TO
1 1/2 FEET OVER WESTERN ONEIDA COUNTY. I CONTINUE TO MENTION BLOW
AND DRIFTING SNOW WITHIN AND NEAR THE SNOW BANDS THEMSELVES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
4 AM UPDATE...
OVERVIEW...SNOW SQUALLS LIKELY FRIDAY NIGHT ALONG AN ARCTIC FRONT
THAT WILL DELIVER BRUTAL COLD SATURDAY AND SATURDAY NIGHT, WHICH
WILL RIVAL WHAT WE SAW LAST FEBRUARY.
FRIDAY/FRIDAY NIGHT....MOST OF FRIDAY WILL BE QUIET WITH A
SOUTHWEST FLOW AHEAD OF AN ARCTIC FRONT. THIS FLOW WILL KEEP MOST
OF THE AREA DRY THROUGH THE DAYLIGHT HOURS. FRIDAY EVENING THE
ARCTIC FRONT WILL CROSS THE AREA BETWEEN 0Z AND 06Z SATURDAY. SNOW
SQUALLS LOOK LIKELY, WITH THE POTENTIAL FOR POOR VISIBILITY AND
SNOWFALL RATES OF MORE THAN AN INCH PER HOUR. MODEL SOUNDINGS SHOW
STEEP LAPSE RATES OF MORE THAN 8.0 C/KM UP THROUGH 650 MB! IN
ADDITION STRONG OMEGA (LIFT/RISING AIR IN THE ATMOSPHERE) IS FOUND
WITH PLENTY OF MOISTURE RIGHT IN THE SNOW GROWTH REGION. THINK BIG
FLAKES, HIGH EFFICIENCY OF ACCUMULATING SNOWS. WILL ADD CHANCE OF
HEAVY SNOW FOR THE FRIDAY EVENING FORECAST. SNOWFALL AMOUNTS OF A
FEW INCHES LIKELY BUT AGAIN IT WILL BE THE RATE OF FALL WHICH WILL
CAUSE POOR VISIBILITIES AND DANGEROUS ROADS.
SATURDAY/SATURDAY NIGHT...BRUTAL COLD. 850 TEMPS FALL TO BETWEEN
-28C AND -30C! "OFFICIAL" HIGHS SATURDAY WILL BE IN THE TEENS AT
MIDNIGHT FRIDAY NIGHT, WITH TEMPS FALLING INTO THE SINGLE DIGITS
BY SATURDAY AFTERNOON. SOME AREAS WILL LIKELY DROP BELOW ZERO FOR
TEMPS SATURDAY AFTERNOON, ESPECIALLY IN NY STATE! THIS ALONE IS
COLD BUT A PRESSURE GRADIENT BETWEEN AN OCEAN STORM AND HIGH
PRESSURE OVER THE MIDWEST WILL PRODUCE ENOUGH WIND FOR WIND CHILL
READINGS BETWEEN -10 AND -30. WE WILL CONTINUE TO HIGHLIGHT THE
HIGH CONFIDENCE FOR EXTREME COLD AND DANGEROUS WIND CHILLS IN OUR
HWO, ON SOCIAL MEDIA, AND IN OUR ONLINE BRIEFING PACKAGE FOUND AT
WEATHER.GOV/BGM UNDER WEATHER HAZARD BRIEFING AT THE BOTTOM OF THE
PAGE. LOWS SATURDAY NIGHT WILL BE BELOW ZERO EVERYWHERE, WITH -20
READINGS POSSIBLE IN OUR COLDER SPOTS. IMPRESSIVE COLD AND THE
ONLY SILVER LINING IS THE FACT IT WON`T LAST LONG. SEE BELOW FOR
MORE ON MILDER WEATHER NEXT WEEK.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
430 PM UPDATE...
ONLY SOME MODERATION IN TEMPERATURES EXPECTED SUNDAY AS ARCTIC
HIGH SLIDES EAST RIGHT OVER THE AREA BY LATE DAY. WINDS WILL BE
SIGNIFICANTLY LESS...YET WE START THE DAY WITH SUBZERO
TEMPERATURES SO VERY COLD ANYWAYS. STILL EXPECT SOME LAKE EFFECT,
THOUGH THIS WILL TEND TO BE DIMINISHING THROUGH THE DAY HAS THE
HIGH MOVES IN. HIGHS LOOK TO RANGE FROM THE SINGLE DIGITS THROUGH
MUCH OF THE CATSKILLS NORTH TO THE TUG HILL WITH LOW TO MID TEENS
ELSEWHERE.
PATTERN WILL BE PROGRESSIVE ENOUGH FOR CORE OF ARCTIC AIR TO MOVE
OUT EARLY NEXT WEEK WITH MORE SIGNIFICANT MODERATION BACK TO AT
LEAST SEASONAL. MODELS INDICATE THE NEXT UPPER TROUGH MOVING INTO
THE EAST WITH LOW PRESSURE DEVELOPMENT BUT THERE IS MODEL
DISAGREEMENT ON TIMING, TRACK, AND INTENSITY. FOR NOW, INDICATE
CHANCE OF SNOW IN GRIDS FOR MONDAY THROUGH WEDNESDAY BUT THERE IS A
CHANCE LOW COULD TRACK FAR ENOUGH WEST TO BRING RAIN TO SOME AREAS
AS EARLY AS TUESDAY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
LE SNOW BAND IS XPCTD TO DROP SWRD ACROSS RME AND STALL IN THE SYR
AREA FOR SVRL HRS TODAY. THIS WEILL BRING BRIEF IFR CONDS TO
RME...AND PROLONGED IFR CIGS AND VSBY TO SYR FOR MUCH OF THE DAY.
ELSEWHERE...SCT SNOW SHWRS WILL BRING BRIEF LWR CONDS BUT MUCH OF
THE DAY WILL BE VFR ELSEWHERE. BAND IS XPCTD TO LIFT NWRD LTR THIS
EVE LVG VFR CONDS AT ALL STATIONS.
.OUTLOOK...
FRI THRU SUN...VARIABLE CEILING AND VSBY RESTRICTIONS DUE TO
PERIODS OF WIDESPREAD LIGHT SNOW AND BANDS OF MORE INTENSE LAKE
EFFECT SNOW...ESPECIALLY NORTHERN HALF. LESS COVERAGE AND TIME
AFFECTED FOR THE SOUTHERN AREAS.
MON...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ016-017-044>046.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST FRIDAY FOR NYZ009-018-
036-037.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN/MSE
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1101 AM EST THU FEB 11 2016
.SYNOPSIS...
COLD WEST-NORTHWESTERLY FLOW WILL REMAIN IN PLACE ACROSS THE LOWER
GREAT LAKES WITH AREAS OF LAKE EFFECT SNOW TODAY. TONIGHT AND
FRIDAY...AHEAD OF THE ARCTIC FRONT SOUTHWESTERLY FLOW WILL DEVELOP
SHIFTING LAKE EFFECT SNOWS BACK NORTHWARD ACROSS BUFFALO AND
WATERTOWN AREAS. BEHIND THE ARCTIC FRONT EXPECT DANGEROUSLY COLD
TEMPERATURES AND WIND CHILLS THROUGH SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WEST-NORTHWESTERLY FLOW OF COLD AIR WILL CONTINUE LAKE EFFECT
SNOWS EAST-SOUTHEAST OF THE LAKES TODAY IN A MULTIBANDED
ORIENTATION DUE TO SHORTER FETCH ACROSS THE LAKES. HIGH PRESSURE
OVER THE OHIO VALLEY WILL EXPAND NORTH AND EAST THROUGH THIS
AFTERNOON AND SHOULD WEAKEN THE LAKE SNOWS SOME FROM WHAT WE SAW
LAST NIGHT AS THE CAPPING INVERSION LOWERS TO AROUND 8KFT.
KBUF RADAR SHOWS A NARROW BAND OF SNOW WITH A GEORGIAN BAY
CONNECTION EXTENDING FROM NIAGARA COUNTY SOUTHEAST TO NORTHERN
ERIE...GENESEE AND LIVINGSTON COUNTIES. THIS SHOULD CONTINUE TO
SETTLE SOUTH THROUGH THIS MORNING WHICH WOULD BRING IT ACROSS METRO
BUFFALO AND INTO WYOMING COUNTIES. THIS BAND COULD BRING A BRIEF
PERIOD OF INTENSE SNOWS WITH REDUCED VISIBILITY AND A QUICK FRESH
COATING OF MAYBE AN INCH OF SNOW AS IT SHIFTS SOUTH.
ACROSS THE SOUTHERN LAKE ONTARIO SHORELINE MULTIPLE NARROW BANDS OF
LAKE EFFECT SNOW WILL CONTINUE TO IMPACT THE SOUTHERN SHORELINE
COUNTIES WHERE WARNINGS WILL REMAIN UP. AN ADDITIONAL INCH OR TWO OF
SNOW IS POSSIBLE FROM NIAGARA EAST TO MONROE COUNTIES FROM THESE
LAKE SNOWS.
FURTHER SOUTH...LAKE SNOWS HAVE LARGELY SETTLED SOUTH TOWARD ERIE PA
WITH JUST SOME SCATTERED SNOW SHOWERS ACROSS THE SOUTHERN TIER. THE
LATEST HRRR MODEL INDICATES THE NARROW BAND OF SNOW NEAR ERIE WILL
SHIFT BACK NORTH ACROSS CHAUTAUQUA AND CATTARAUGUS COUNTIES THIS
AFTERNOON WITH A POTENTIAL FOR 2-3 ADDITIONAL INCHES OF SNOW WHICH
IS WHY THE LAKE EFFECT SNOW WARNINGS WILL REMAIN IN EFFECT DESPITE
THIS THE CURRENT LULL IN ACTIVITY.
KTYX RADAR CONTINUES TO SHOW SEVERAL NARROW BANDS OF LAKE EFFECT
SNOW IMPACTING NORTHEAST WAYNE...NORTHERN CAYUGA AND OSWEGO COUNTY
WHICH MAY BRING AN ADDITIONAL 1-3 INCHES THROUGH TODAY. THERE ARE
ALSO SOME LIGHT SNOW SHOWERS FURTHER NORTH DRIFTING ACROSS JEFFERSON
AND LEWIS COUNTIES WHICH SHOULD ONLY BRING UP TO AN ADDITIONAL INCH
THROUGH TODAY.
OUTSIDE OF THE MAIN LAKE EFFECT SNOW AREAS...THE REMAINDER OF THE
REGION WILL JUST EXPERIENCE MUCH LIGHTER AND MUCH MORE SCATTERED
TRANSIENT LAKE AND OROGRAPHICALLY-DRIVEN LIGHT SNOW SHOWERS...WITH
ONLY MINOR ADDITIONAL ACCUMULATIONS EXPECTED. OTHERWISE IT WILL
BE COLD AND ON THE BRISK SIDE AGAIN...WITH DAYTIME HIGHS ONLY
RANGING FROM AROUND 10 ABOVE ACROSS THE HIGHEST TERRAIN TO THE MID
TEENS ELSEWHERE.
TONIGHT...A CONTINUED WEST-NORTHWESTERLY FLOW WILL CONTINUE TO
MAINTAIN WEAKER LAKE SNOWS SOUTHEAST OF THE LAKES FOR A GOOD
PORTION OF THIS EVENING...WITH THIS ACTIVITY BEING HELD MORE
IN CHECK BY THE AFOREMENTIONED LOWERING CAPPING INVERSION...
WHICH WILL RUN BETWEEN 3 AND 5 KFT OFF LAKE ERIE...AND WILL DROP
TO BETWEEN 4 AND 5 KFT OFF LAKE ONTARIO. AFTER THAT TIME...GRADUAL
BACKING OF THE LOW LEVEL FLOW TO WESTERLY AND THEN WEST-SOUTHWESTERLY
IN ADVANCE OF AN APPROACHING ARCTIC FRONT WILL RESULT IN THE LAKE
BANDS SLOWLY MIGRATING NORTHWARD THROUGH THE BALANCE OF THE NIGHT...
WITH THE LAKE ERIE ACTIVITY REACHING THE BUFFALO SOUTHTOWNS...AND
THE LAKE ONTARIO LAKE SNOWS REACHING THE TUG HILL REGION BY
DAYBREAK. WHILE A CONTINUED LOWER CAP AND INCREASING AMOUNTS
OF DIRECTIONAL SHEAR BELOW IT SHOULD KEEP THE MIGRATING LAKE
SNOWS FROM BECOMING TERRIBLY ORGANIZED...THE GRADUALLY INCREASING
FETCH ACROSS BOTH LAKES SHOULD ALLOW FOR AT LEAST SOME INCREASE
IN STRENGTH LATE...ENOUGH FOR THE BANDS TO PRODUCE AN ADDITIONAL
INCH OR TWO OF ACCUMULATION DURING THEIR NORTHWARD MIGRATION.
AT THIS POINT IT APPEARS THAT THE MORE SIGNIFICANT ACCUMULATIONS
FROM THESE WILL HOLD OFF UNTIL DURING THE DAY ON FRIDAY...WHEN
DEEPENING MOISTURE AND A RISING CAP OUT IN ADVANCE OF THE
APPROACHING ARCTIC BOUNDARY SHOULD ALLOW FOR A NOTEWORTHY UPTICK
IN BAND ORGANIZATION...MORE ON WHICH IS DISCUSSED IN THE SHORT
TERM SECTION BELOW.
OUTSIDE OF THE LAKE SNOWS...EXPECT A QUIET AND LARGELY DRY NIGHT
TONIGHT...WITH LOWS RANGING FROM AROUND ZERO ACROSS THE NORTH
COUNTRY TO THE 5 TO 10 ABOVE RANGE ELSEWHERE. GIVEN A DEVELOPING
WARM AIR ADVECTION REGIME...THESE WILL LIKELY OCCUR AROUND
MIDNIGHT...BEFORE GIVING WAY TO SLOWLY RISING TEMPERATURES
OVERNIGHT.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
LAKE SNOWS WILL REORGANIZE AND INTENSIFY FRIDAY AS THE FLOW BACKS
TO SOUTHWEST IN RESPONSE TO A WEAK LOW DROPPING SOUTH FROM CANADA
AND AHEAD OF THE ADVANCING ARCTIC BOUNDARY.
OFF LAKE ERIE...FORECAST SOUNDINGS CONTINUE TO SHOW A FAIRLY WELL
ALIGNED SOUTHWEST FLOW LOW LEVEL FLOW DEVELOPING EARLY FRIDAY.
INITIALLY MOISTURE WILL BE LIMITED...BUT WITH THE APPROACH OF THE
LOW AND LONG FETCH DOWN THE LAKE...EXPECT A FAIRLY CONSOLIDATED AND
INTENSE LAKE EFFECT BAND TO DEVELOP. CONSENSUS HIGH RESOLUTION
GUIDANCE CONTINUES TO REFLECT THESE TRENDS. THE RGEM ALONG WITH THE
NAM/GFS ALL SUGGEST A STRONG CONVERGENCE SHOULD CONTINUE TO LIFT
NORTHWARD INTO BUFFALO METRO AREA DURING THE DAY FRIDAY. FAVORABLE
LAKE PARAMETERS WILL EXIST WITH PLENTY OF OVER-LAKE INSTABILITY AS
INVERSION HEIGHTS APPROACH 10K FEET WITHIN A WELL ALIGNED SOUTHWEST
FLOW...WITH THE BAND POSSIBLY EXTENDING INLAND ACROSS WYOMING AND
GENESEE COUNTIES...AND EVEN PERHAPS AS FAR NORTH AS NIAGARA AND
ORLEANS COUNTIES IF THE FLOW CAN BACK ENOUGH. FOR NOW WILL MAINTAIN
THE LAKE EFFECT SNOW DUE TO UNCERTAINTIES IN THE EXACT PLACEMENT OF
THE HEAVIEST BAND.
OFF LAKE ONTARIO...A WELL ALIGNED SOUTHWESTERLY FLOW IS FORECAST TO
DEVELOP FRIDAY SIMILAR TO LAKE ERIE. THIS WILL NOT ONLY TAP INTO
MOISTURE FROM AN APPROACHING SHORTWAVE...BUT ALSO MOISTURE FROM
WHATEVER FORMS OFF LAKE ERIE. THIS WILL BRING THE POTENTIAL FOR
SIGNIFICANT SNOWS ON FRIDAY INTO FRIDAY NIGHT FOR WATERTOWN AND
VICINITY...WITH THE BAND POSSIBLY EXTENDING INLAND ACROSS NORTHERN
LEWIS COUNTY. 850 MB TEMPERATURES AROUND -16C AND INVERSION HEIGHTS
FORECAST TO RISE TO NEARLY 15K FT AND A FAVORABLY DENDRITIC SNOW
GROWTH ZONE SHOULD PROVIDE FAVORABLE PARAMETERS FOR SIGNIFICANT
SNOWS. WILL MAINTAIN THE LAKE EFFECT SNOW WATCH FOR JEFFERSON COUNTY
AND ADD LEWIS COUNTY WITH THE POTENTIAL FOR SIGNIFICANT LAKE SNOWS
REACHING THE NORTHERN PART OF THE COUNTY.
ON FRIDAY EVENING...A POWERFUL ARCTIC FRONT WILL SURGE SOUTH ACROSS
THE REGION. THIS ARCTIC FRONT WILL LIKELY CAPTURE AND MERGE WITH THE
LAKE EFFECT SNOW BAND OFF LAKE ONTARIO...WITH A VERY HEAVY SNOW
SQUALL PASSING SOUTH ACROSS THE EASTERN LAKE ONTARIO REGION. THIS
WILL LIKELY PRODUCE AN INCH OR TWO OF SNOW IN MANY AREAS...WITH
LOCALLY HIGHER AMOUNTS SOUTHEAST OF THE LAKES WHERE THE LAKE
CONTRIBUTION MAXIMIZES. BEHIND THE ARCTIC FRONT...MULTIPLE STREAMERS
OF LAKE EFFECT SNOW SHOWERS WILL DEVELOP SOUTH OF THE LAKES LATE
FRIDAY NIGHT AS FLOW BECOMES NORTHWEST AND EVENTUALLY NORTH
NORTHWEST. THE FRONT WILL ALSO USHER IN BITTERLY COLD TEMPERATURES
WHICH WILL BE BELOW ZERO IN MOST AREAS BY DAYBREAK SATURDAY.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A FRIGID ARCTIC AIRMASS WILL TAKE HOLD OF THE EASTERN GREAT LAKES
AND NEW ENGLAND THIS WEEKEND. A CONSENSUS OF 12Z GUIDANCE DROPS
850MB TEMPERATURES TO AROUND -30C AT BUFFALO DURING THE DAY AT
BUFFALO...WITH -33C ACROSS THE EASTERN LAKE ONTARIO REGION. THE
COLDEST TEMPERATURE EVER RECORDED AT 850MB ON A KBUF SOUNDING IN THE
MONTH OF FEBRUARY IS -28C...AND THE COLDEST EVER RECORDED FOR ANY
MONTH IS -32C.
THIS WILL RESULT IN BITTERLY COLD TEMPERATURES DURING THE DAY
SATURDAY WITH DAYTIME TEMPERATURES STRUGGLING TO RISE ABOVE ZERO.
DAYTIME HIGHS WILL ALMOST CERTAINLY BE BELOW ZERO IN THE EASTERN
LAKE ONTARIO REGION. PERSISTENT WINDS OF 10 TO 15 MPH ON SATURDAY
NIGHT WILL LIMIT RADIATIONAL COOLING...BUT EVEN SO IT WILL BE VERY
COLD WITH BELOW ZERO LOWS REGION-WIDE. LOWS OF -20F OR COLDER ARE
POSSIBLE ACROSS THE NORTH COUNTRY WITH NO MODERATING LAKE INFLUENCE.
THE COMBINATION OF MODERATE WINDS AND FRIGID TEMPERATURES WILL
PRODUCE DANGEROUSLY COLD WIND CHILLS LATE FRIDAY NIGHT THROUGH EARLY
SUNDAY MORNING. ISSUING A WIND CHILL WATCH FOR THE ENTIRE
CWA...AREAS NEAR THE LAKESHORES MAY ONLY REACH ADVISORY CRITERIA
HOWEVER NEED TO HIGHLIGHT THIS DANGEROUSLY COLD WEATHER.
THE FRIGID NORTH FLOW OVER THE LAKES WILL PRODUCE WIDESPREAD LAKE
EFFECT SNOW SHOWERS ACROSS WESTERN AND CENTRAL NY. DESPITE THE
EXTREME INSTABILITY...AIRMASSES THIS COLD ARE ALSO VERY DRY AND
TEMPERATURES BECOME TOO COLD FOR DENDRITES. THIS WILL FORCE
SNOWFLAKES TO BE VERY SMALL AND LIMIT ACCUMULATIONS...ALTHOUGH
SEVERAL INCHES ARE LIKELY SOUTH OF BOTH LAKES. THE LAKE EFFECT SNOW
WILL DIMINISH IN COVERAGE AND INTENSITY SUNDAY. 12Z GUIDANCE IS A
BIT FASTER MOVING THE SURFACE RIDGE ACROSS THE REGION...WITH LAKE
EFFECT SNOW LIKELY TO TAPER OFF BY SUNDAY NIGHT.
AFTER THIS THERE IS GENERAL MODEL AGREEMENT THAT TEMPERATURES WILL
WARM BACK TO NEAR NORMAL EARLY NEXT WEEK. HOWEVER...THE 12Z ECMWF
IS SIGNIFICANTLY DIFFERENT FROM THE GFS/GGEM. THE ECMWF HAS
CONSISTENTLY DEVELOPED A STRONG WAVE OF LOW PRESSURE WITH
SIGNIFICANT QPF ACROSS OUR REGION WHICH WOULD FALL AS RAIN OR
SNOW. THE GGEM/GFS HAVE THIS SYSTEM BUT KEEP IT WELL TO OUR
EAST...AND INSTEAD ARE A BIT COLDER WITH A CHANCE FOR LIGHT SNOW
SHOWERS. THE FORECAST WILL REFLECT A CONSENSUS BETWEEN THIS
GUIDANCE...WITH NEAR NORMAL TEMPERATURES AND CHANCE POPS.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
LAKE EFFECT SNOWS AND ATTENDANT IFR/LIFR WILL BE FOUND EAST-
SOUTHEAST OF THE LAKES TODAY AND INTO THIS EVENING...WITH MVFR/VFR
CONDITIONS AND MUCH MORE SCATTERED SNOW SHOWERS PREVAILING
ELSEWHERE. EXPECT THE MOST SIGNIFICANT LAKE SNOWS OF THE DAY TO
COME THIS MORNING...WITH THE ACTIVITY THEN GRADUALLY WEAKENING
FROM WEST TO EAST THIS AFTERNOON AND EVENING IN CONJUNCTION WITH
DIMINISHING UPSTREAM CONNECTIONS...THE INTRUSION OF DRIER AIR
ALOFT...AND A LOWERING CAPPING INVERSION.
FROM THE LATE EVENING HOURS ON THROUGH THE REMAINDER OF
TONIGHT... GRADUAL BACKING OF THE LOW LEVEL FLOW TO WESTERLY AND
THEN WEST- SOUTHWESTERLY IN ADVANCE OF AN APPROACHING ARCTIC FRONT
WILL RESULT IN WEAKER LAKE SNOWS SLOWLY MIGRATING NORTHWARD...WITH
THE LAKE ERIE ACTIVITY REACHING THE BUFFALO SOUTHTOWNS...AND THE
LAKE ONTARIO LAKE SNOWS REACHING THE TUG HILL REGION BY 12Z
FRIDAY. EXPECT IFR/MVFR TO PREVAIL WITHIN THE MIGRATING LAKE
SNOWS...WITH GENERAL VFR CONDITIONS THE RULE ELSEWHERE.
OUTLOOK...
FRIDAY...IFR/MVFR WITH SNOW SHOWERS LIKELY...AND AREAS OF
HEAVIER LAKE EFFECT SNOW EAST/NORTHEAST OF THE LAKES.
SATURDAY...IFR/MVFR IN LAKE EFFECT SNOW SHOWERS SOUTH OF THE LAKES...
WITH MVFR/VFR ACROSS THE NORTH COUNTRY.
SUNDAY...A CHANCE OF IFR/MVFR IN WEAKENING LAKE EFFECT SNOW SHOWERS
SOUTH OF THE LAKES...OTHERWISE MVFR/VFR.
MONDAY...MAINLY VFR WITH A CHANCE OF SNOW SHOWERS.
&&
.MARINE...
A BRISK FLOW OF PROGRESSIVELY COLDER ARCTIC AIR WILL CONTINUE TO
OVERSPREAD THE REGION THROUGH THE WEEKEND...RESULTING IN A PROLONGED
PERIOD OF ADVISORY-WORTHY WINDS AND WAVES ACROSS THE LOWER LAKES.
IN ADDITION TO THE ABOVE...THE PASSAGE OF AN ARCTIC COLD FRONT LATER
FRIDAY AFTERNOON AND FRIDAY EVENING WILL ALSO USHER IN A TRULY FRIGID
AIRMASS FOR LATER FRIDAY NIGHT AND THE UPCOMING WEEKEND...WHICH IN
CONJUNCTION WITH THE AFOREMENTIONED WINDS WILL RESULT IN A GREATLY
HEIGHTENED POTENTIAL FOR HEAVY FREEZING SPRAY.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...LAKE EFFECT SNOW WATCH FROM LATE TONIGHT THROUGH LATE FRIDAY
NIGHT FOR NYZ007-008.
WIND CHILL WATCH FROM LATE FRIDAY NIGHT THROUGH SUNDAY MORNING
FOR NYZ001>008-010>014-019>021-085.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST FRIDAY FOR NYZ004>006.
LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THIS AFTERNOON FOR
NYZ001>003-019-020.
LAKE EFFECT SNOW WATCH FROM LATE TONIGHT THROUGH FRIDAY
EVENING FOR NYZ012-019-020-085.
LAKE EFFECT SNOW WATCH FROM LATE TONIGHT THROUGH FRIDAY
EVENING FOR NYZ010-011.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LEZ020.
SMALL CRAFT ADVISORY UNTIL 7 PM EST SATURDAY FOR LEZ040-
041.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR
LOZ030.
SMALL CRAFT ADVISORY UNTIL 7 PM EST SATURDAY FOR
LOZ042>045.
&&
$$
SYNOPSIS...AR/JJR
NEAR TERM...JJR/SMITH
SHORT TERM...LEVAN/TMA
LONG TERM...APFFEL/LEVAN
AVIATION...JJR/SMITH
MARINE...JJR/SMITH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1029 AM EST THU FEB 11 2016
.SYNOPSIS...
A GENERAL WEST-NORTHWESTERLY FLOW OF COLD AIR WILL CONTINUE
ACROSS THE LOWER GREAT LAKES TODAY AND INTO THIS EVENING...WHICH
WILL MAINTAIN AREAS OF LAKE EFFECT SNOW SOUTHEAST OF THE LAKES.
WINDS WILL THEN TURN MORE SOUTHWESTERLY LATER TONIGHT AND FRIDAY
OUT IN ADVANCE OF AN APPROACHING ARCTIC COLD FRONT...RESULTING IN
THE LAKE SNOWS LIFTING NORTHWARD TO THE BUFFALO AND WATERTOWN
AREAS. THE ARCTIC FRONT ITSELF WILL THEN CROSS THE REGION LATE
FRIDAY AFTERNOON AND FRIDAY EVENING WHILE BRINGING A BURST OF SNOW
TO MOST AREAS... WITH DOWNRIGHT FRIGID CONDITIONS AND DANGEROUSLY
COLD WIND CHILLS THEN FOLLOWING IN ITS WAKE FOR FRIDAY NIGHT
THROUGH SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WEST-NORTHWESTERLY FLOW OF COLD AIR WILL CONTINUE LAKE EFFECT
SNOWS EAST-SOUTHEAST OF THE LAKES TODAY IN A MULTIBANDED
ORIENTATION DUE TO SHORTER FETCH ACROSS THE LAKES. HIGH PRESSURE
OVER THE OHIO VALLEY WILL EXPAND NORTH AND EAST THROUGH THIS
AFTERNOON AND SHOULD WEAKEN THE LAKE SNOWS SOME FROM WHAT WE SAW
LAST NIGHT AS THE CAPPING INVERSION LOWERS TO AROUND 8KFT.
KBUF RADAR SHOWS A NARROW BAND OF SNOW WITH A GEORGIAN BAY
CONNECTION EXTENDING FROM NIAGARA COUNTY SOUTHEAST TO NORTHERN
ERIE...GENESEE AND LIVINGSTON COUNTIES. THIS SHOULD CONTINUE TO
SETTLE SOUTH THROUGH THIS MORNING WHICH WOULD BRING IT ACROSS METRO
BUFFALO AND INTO WYOMING COUNTIES. THIS BAND COULD BRING A BRIEF
PERIOD OF INTENSE SNOWS WITH REDUCED VISIBILITY AND A QUICK FRESH
COATING OF MAYBE AN INCH OF SNOW AS IT SHIFTS SOUTH.
ACROSS THE SOUTHERN LAKE ONTARIO SHORELINE MULTIPLE NARROW BANDS OF
LAKE EFFECT SNOW WILL CONTINUE TO IMPACT THE SOUTHERN SHORELINE
COUNTIES WHERE WARNINGS WILL REMAIN UP. AN ADDITIONAL INCH OR TWO OF
SNOW IS POSSIBLE FROM NIAGARA EAST TO MONROE COUNTIES FROM THESE
LAKE SNOWS.
FURTHER SOUTH...LAKE SNOWS HAVE LARGELY SETTLED SOUTH TOWARD ERIE PA
WITH JUST SOME SCATTERED SNOW SHOWERS ACROSS THE SOUTHERN TIER. THE
LATEST HRRR MODEL INDICATES THE NARROW BAND OF SNOW NEAR ERIE WILL
SHIFT BACK NORTH ACROSS CHAUTAUQUA AND CATTARAUGUS COUNTIES THIS
AFTERNOON WITH A POTENTIAL FOR 2-3 ADDITIONAL INCHES OF SNOW WHICH
IS WHY THE LAKE EFFECT SNOW WARNINGS WILL REMAIN IN EFFECT DESPITE
THIS THE CURRENT LULL IN ACTIVITY.
KTYX RADAR CONTINUES TO SHOW SEVERAL NARROW BANDS OF LAKE EFFECT
SNOW IMPACTING NORTHEAST WAYNE...NORTHERN CAYUGA AND OSWEGO COUNTY
WHICH MAY BRING AN ADDITIONAL 1-3 INCHES THROUGH TODAY. THERE ARE
ALSO SOME LIGHT SNOW SHOWERS FURTHER NORTH DRIFTING ACROSS JEFFERSON
AND LEWIS COUNTIES WHICH SHOULD ONLY BRING UP TO AN ADDITIONAL INCH
THROUGH TODAY.
OUTSIDE OF THE MAIN LAKE EFFECT SNOW AREAS...THE REMAINDER OF THE
REGION WILL JUST EXPERIENCE MUCH LIGHTER AND MUCH MORE SCATTERED
TRANSIENT LAKE AND OROGRAPHICALLY-DRIVEN LIGHT SNOW SHOWERS...WITH
ONLY MINOR ADDITIONAL ACCUMULATIONS EXPECTED. OTHERWISE IT WILL
BE COLD AND ON THE BRISK SIDE AGAIN...WITH DAYTIME HIGHS ONLY
RANGING FROM AROUND 10 ABOVE ACROSS THE HIGHEST TERRAIN TO THE MID
TEENS ELSEWHERE.
TONIGHT...A CONTINUED WEST-NORTHWESTERLY FLOW WILL CONTINUE TO
MAINTAIN WEAKER LAKE SNOWS SOUTHEAST OF THE LAKES FOR A GOOD
PORTION OF THIS EVENING...WITH THIS ACTIVITY BEING HELD MORE
IN CHECK BY THE AFOREMENTIONED LOWERING CAPPING INVERSION...
WHICH WILL RUN BETWEEN 3 AND 5 KFT OFF LAKE ERIE...AND WILL DROP
TO BETWEEN 4 AND 5 KFT OFF LAKE ONTARIO. AFTER THAT TIME...GRADUAL
BACKING OF THE LOW LEVEL FLOW TO WESTERLY AND THEN WEST-SOUTHWESTERLY
IN ADVANCE OF AN APPROACHING ARCTIC FRONT WILL RESULT IN THE LAKE
BANDS SLOWLY MIGRATING NORTHWARD THROUGH THE BALANCE OF THE NIGHT...
WITH THE LAKE ERIE ACTIVITY REACHING THE BUFFALO SOUTHTOWNS...AND
THE LAKE ONTARIO LAKE SNOWS REACHING THE TUG HILL REGION BY
DAYBREAK. WHILE A CONTINUED LOWER CAP AND INCREASING AMOUNTS
OF DIRECTIONAL SHEAR BELOW IT SHOULD KEEP THE MIGRATING LAKE
SNOWS FROM BECOMING TERRIBLY ORGANIZED...THE GRADUALLY INCREASING
FETCH ACROSS BOTH LAKES SHOULD ALLOW FOR AT LEAST SOME INCREASE
IN STRENGTH LATE...ENOUGH FOR THE BANDS TO PRODUCE AN ADDITIONAL
INCH OR TWO OF ACCUMULATION DURING THEIR NORTHWARD MIGRATION.
AT THIS POINT IT APPEARS THAT THE MORE SIGNIFICANT ACCUMULATIONS
FROM THESE WILL HOLD OFF UNTIL DURING THE DAY ON FRIDAY...WHEN
DEEPENING MOISTURE AND A RISING CAP OUT IN ADVANCE OF THE
APPROACHING ARCTIC BOUNDARY SHOULD ALLOW FOR A NOTEWORTHY UPTICK
IN BAND ORGANIZATION...MORE ON WHICH IS DISCUSSED IN THE SHORT
TERM SECTION BELOW.
OUTSIDE OF THE LAKE SNOWS...EXPECT A QUIET AND LARGELY DRY NIGHT
TONIGHT...WITH LOWS RANGING FROM AROUND ZERO ACROSS THE NORTH
COUNTRY TO THE 5 TO 10 ABOVE RANGE ELSEWHERE. GIVEN A DEVELOPING
WARM AIR ADVECTION REGIME...THESE WILL LIKELY OCCUR AROUND
MIDNIGHT...BEFORE GIVING WAY TO SLOWLY RISING TEMPERATURES
OVERNIGHT.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
LAKE SNOWS WILL REORGANIZE AND INTENSIFY FRIDAY AS THE FLOW BACKS
TO SOUTHWEST IN RESPONSE TO A WEAK LOW DROPPING SOUTH FROM CANADA
AND AHEAD OF THE ADVANCING ARCTIC BOUNDARY.
OFF LAKE ERIE...FORECAST SOUNDINGS CONTINUE TO SHOW A FAIRLY WELL
ALIGNED SOUTHWEST FLOW LOW LEVEL FLOW DEVELOPING EARLY FRIDAY.
INITIALLY MOISTURE WILL BE LIMITED...BUT WITH THE APPROACH OF THE
LOW AND LONG FETCH DOWN THE LAKE...EXPECT A FAIRLY CONSOLIDATED AND
INTENSE LAKE EFFECT BAND TO DEVELOP. CONSENSUS HIGH RESOLUTION
GUIDANCE CONTINUES TO REFLECT THESE TRENDS. THE RGEM ALONG WITH THE
NAM/GFS ALL SUGGEST A STRONG CONVERGENCE SHOULD CONTINUE TO LIFT
NORTHWARD INTO BUFFALO METRO AREA DURING THE DAY FRIDAY. FAVORABLE
LAKE PARAMETERS WILL EXIST WITH PLENTY OF OVER-LAKE INSTABILITY AS
INVERSION HEIGHTS APPROACH 10K FEET WITHIN A WELL ALIGNED SOUTHWEST
FLOW...WITH THE BAND POSSIBLY EXTENDING INLAND ACROSS WYOMING AND
GENESEE COUNTIES...AND EVEN PERHAPS AS FAR NORTH AS NIAGARA AND
ORLEANS COUNTIES IF THE FLOW CAN BACK ENOUGH. FOR NOW WILL MAINTAIN
THE LAKE EFFECT SNOW DUE TO UNCERTAINTIES IN THE EXACT PLACEMENT OF
THE HEAVIEST BAND.
OFF LAKE ONTARIO...A WELL ALIGNED SOUTHWESTERLY FLOW IS FORECAST TO
DEVELOP FRIDAY SIMILAR TO LAKE ERIE. THIS WILL NOT ONLY TAP INTO
MOISTURE FROM AN APPROACHING SHORTWAVE...BUT ALSO MOISTURE FROM
WHATEVER FORMS OFF LAKE ERIE. THIS WILL BRING THE POTENTIAL FOR
SIGNIFICANT SNOWS ON FRIDAY INTO FRIDAY NIGHT FOR WATERTOWN AND
VICINITY...WITH THE BAND POSSIBLY EXTENDING INLAND ACROSS NORTHERN
LEWIS COUNTY. 850 MB TEMPERATURES AROUND -16C AND INVERSION HEIGHTS
FORECAST TO RISE TO NEARLY 15K FT AND A FAVORABLY DENDRITIC SNOW
GROWTH ZONE SHOULD PROVIDE FAVORABLE PARAMETERS FOR SIGNIFICANT
SNOWS. WILL MAINTAIN THE LAKE EFFECT SNOW WATCH FOR JEFFERSON COUNTY
AND ADD LEWIS COUNTY WITH THE POTENTIAL FOR SIGNIFICANT LAKE SNOWS
REACHING THE NORTHERN PART OF THE COUNTY.
ON FRIDAY EVENING...A POWERFUL ARCTIC FRONT WILL SURGE SOUTH ACROSS
THE REGION. THIS ARCTIC FRONT WILL LIKELY CAPTURE AND MERGE WITH THE
LAKE EFFECT SNOW BAND OFF LAKE ONTARIO...WITH A VERY HEAVY SNOW
SQUALL PASSING SOUTH ACROSS THE EASTERN LAKE ONTARIO REGION. THIS
WILL LIKELY PRODUCE AN INCH OR TWO OF SNOW IN MANY AREAS...WITH
LOCALLY HIGHER AMOUNTS SOUTHEAST OF THE LAKES WHERE THE LAKE
CONTRIBUTION MAXIMIZES. BEHIND THE ARCTIC FRONT...MULTIPLE STREAMERS
OF LAKE EFFECT SNOW SHOWERS WILL DEVELOP SOUTH OF THE LAKES LATE
FRIDAY NIGHT AS FLOW BECOMES NORTHWEST AND EVENTUALLY NORTH
NORTHWEST. THE FRONT WILL ALSO USHER IN BITTERLY COLD TEMPERATURES
WHICH WILL BE BELOW ZERO IN MOST AREAS BY DAYBREAK SATURDAY.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A FRIGID ARCTIC AIRMASS WILL TAKE HOLD OF THE EASTERN GREAT LAKES
AND NEW ENGLAND THIS WEEKEND. A CONSENSUS OF 12Z GUIDANCE DROPS
850MB TEMPERATURES TO AROUND -30C AT BUFFALO DURING THE DAY AT
BUFFALO...WITH -33C ACROSS THE EASTERN LAKE ONTARIO REGION. THE
COLDEST TEMPERATURE EVER RECORDED AT 850MB ON A KBUF SOUNDING IN THE
MONTH OF FEBRUARY IS -28C...AND THE COLDEST EVER RECORDED FOR ANY
MONTH IS -32C.
THIS WILL RESULT IN BITTERLY COLD TEMPERATURES DURING THE DAY
SATURDAY WITH DAYTIME TEMPERATURES STRUGGLING TO RISE ABOVE ZERO.
DAYTIME HIGHS WILL ALMOST CERTAINLY BE BELOW ZERO IN THE EASTERN
LAKE ONTARIO REGION. PERSISTENT WINDS OF 10 TO 15 MPH ON SATURDAY
NIGHT WILL LIMIT RADIATIONAL COOLING...BUT EVEN SO IT WILL BE VERY
COLD WITH BELOW ZERO LOWS REGION-WIDE. LOWS OF -20F OR COLDER ARE
POSSIBLE ACROSS THE NORTH COUNTRY WITH NO MODERATING LAKE INFLUENCE.
THE COMBINATION OF MODERATE WINDS AND FRIGID TEMPERATURES WILL
PRODUCE DANGEROUSLY COLD WIND CHILLS LATE FRIDAY NIGHT THROUGH EARLY
SUNDAY MORNING. ISSUING A WIND CHILL WATCH FOR THE ENTIRE
CWA...AREAS NEAR THE LAKESHORES MAY ONLY REACH ADVISORY CRITERIA
HOWEVER NEED TO HIGHLIGHT THIS DANGEROUSLY COLD WEATHER.
THE FRIGID NORTH FLOW OVER THE LAKES WILL PRODUCE WIDESPREAD LAKE
EFFECT SNOW SHOWERS ACROSS WESTERN AND CENTRAL NY. DESPITE THE
EXTREME INSTABILITY...AIRMASSES THIS COLD ARE ALSO VERY DRY AND
TEMPERATURES BECOME TOO COLD FOR DENDRITES. THIS WILL FORCE
SNOWFLAKES TO BE VERY SMALL AND LIMIT ACCUMULATIONS...ALTHOUGH
SEVERAL INCHES ARE LIKELY SOUTH OF BOTH LAKES. THE LAKE EFFECT SNOW
WILL DIMINISH IN COVERAGE AND INTENSITY SUNDAY. 12Z GUIDANCE IS A
BIT FASTER MOVING THE SURFACE RIDGE ACROSS THE REGION...WITH LAKE
EFFECT SNOW LIKELY TO TAPER OFF BY SUNDAY NIGHT.
AFTER THIS THERE IS GENERAL MODEL AGREEMENT THAT TEMPERATURES WILL
WARM BACK TO NEAR NORMAL EARLY NEXT WEEK. HOWEVER...THE 12Z ECMWF
IS SIGNIFICANTLY DIFFERENT FROM THE GFS/GGEM. THE ECMWF HAS
CONSISTENTLY DEVELOPED A STRONG WAVE OF LOW PRESSURE WITH
SIGNIFICANT QPF ACROSS OUR REGION WHICH WOULD FALL AS RAIN OR
SNOW. THE GGEM/GFS HAVE THIS SYSTEM BUT KEEP IT WELL TO OUR
EAST...AND INSTEAD ARE A BIT COLDER WITH A CHANCE FOR LIGHT SNOW
SHOWERS. THE FORECAST WILL REFLECT A CONSENSUS BETWEEN THIS
GUIDANCE...WITH NEAR NORMAL TEMPERATURES AND CHANCE POPS.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
LAKE EFFECT SNOWS AND ATTENDANT IFR/LIFR WILL BE FOUND EAST-
SOUTHEAST OF THE LAKES TODAY AND INTO THIS EVENING...WITH MVFR/VFR
CONDITIONS AND MUCH MORE SCATTERED SNOW SHOWERS PREVAILING
ELSEWHERE. EXPECT THE MOST SIGNIFICANT LAKE SNOWS OF THE DAY TO
COME THIS MORNING...WITH THE ACTIVITY THEN GRADUALLY WEAKENING
FROM WEST TO EAST THIS AFTERNOON AND EVENING IN CONJUNCTION WITH
DIMINISHING UPSTREAM CONNECTIONS...THE INTRUSION OF DRIER AIR
ALOFT...AND A LOWERING CAPPING INVERSION.
FROM THE LATE EVENING HOURS ON THROUGH THE REMAINDER OF
TONIGHT... GRADUAL BACKING OF THE LOW LEVEL FLOW TO WESTERLY AND
THEN WEST- SOUTHWESTERLY IN ADVANCE OF AN APPROACHING ARCTIC FRONT
WILL RESULT IN WEAKER LAKE SNOWS SLOWLY MIGRATING NORTHWARD...WITH
THE LAKE ERIE ACTIVITY REACHING THE BUFFALO SOUTHTOWNS...AND THE
LAKE ONTARIO LAKE SNOWS REACHING THE TUG HILL REGION BY 12Z
FRIDAY. EXPECT IFR/MVFR TO PREVAIL WITHIN THE MIGRATING LAKE
SNOWS...WITH GENERAL VFR CONDITIONS THE RULE ELSEWHERE.
OUTLOOK...
FRIDAY...IFR/MVFR WITH SNOW SHOWERS LIKELY...AND AREAS OF
HEAVIER LAKE EFFECT SNOW EAST/NORTHEAST OF THE LAKES.
SATURDAY...IFR/MVFR IN LAKE EFFECT SNOW SHOWERS SOUTH OF THE LAKES...
WITH MVFR/VFR ACROSS THE NORTH COUNTRY.
SUNDAY...A CHANCE OF IFR/MVFR IN WEAKENING LAKE EFFECT SNOW SHOWERS
SOUTH OF THE LAKES...OTHERWISE MVFR/VFR.
MONDAY...MAINLY VFR WITH A CHANCE OF SNOW SHOWERS.
&&
.MARINE...
A BRISK FLOW OF PROGRESSIVELY COLDER ARCTIC AIR WILL CONTINUE TO
OVERSPREAD THE REGION THROUGH THE WEEKEND...RESULTING IN A PROLONGED
PERIOD OF ADVISORY-WORTHY WINDS AND WAVES ACROSS THE LOWER LAKES.
IN ADDITION TO THE ABOVE...THE PASSAGE OF AN ARCTIC COLD FRONT LATER
FRIDAY AFTERNOON AND FRIDAY EVENING WILL ALSO USHER IN A TRULY FRIGID
AIRMASS FOR LATER FRIDAY NIGHT AND THE UPCOMING WEEKEND...WHICH IN
CONJUNCTION WITH THE AFOREMENTIONED WINDS WILL RESULT IN A GREATLY
HEIGHTENED POTENTIAL FOR HEAVY FREEZING SPRAY.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...LAKE EFFECT SNOW WATCH FROM LATE TONIGHT THROUGH LATE FRIDAY
NIGHT FOR NYZ007-008.
WIND CHILL WATCH FROM LATE FRIDAY NIGHT THROUGH SUNDAY MORNING
FOR NYZ001>008-010>014-019>021-085.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST FRIDAY FOR NYZ004>006.
LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THIS AFTERNOON FOR
NYZ001>003-019-020.
LAKE EFFECT SNOW WATCH FROM LATE TONIGHT THROUGH FRIDAY
EVENING FOR NYZ012-019-020-085.
LAKE EFFECT SNOW WATCH FROM LATE TONIGHT THROUGH FRIDAY
EVENING FOR NYZ010-011.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LEZ020.
SMALL CRAFT ADVISORY UNTIL 7 PM EST SATURDAY FOR LEZ040-
041.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR
LOZ030.
SMALL CRAFT ADVISORY UNTIL 7 PM EST SATURDAY FOR
LOZ042>045.
&&
$$
SYNOPSIS...JJR
NEAR TERM...JJR/SMITH
SHORT TERM...TMA
LONG TERM...APFFEL/LEVAN
AVIATION...JJR/SMITH
MARINE...JJR/SMITH
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
639 AM EST THU FEB 11 2016
.SYNOPSIS...
LAKE EFFECT SNOW WILL BE HEAVY AT TIMES THROUGH TONIGHT IN PARTS
OF CENTRAL NEW YORK...GENERALLY SOUTHEAST OF LAKE ONTARIO.
SCATTERED SNOW SHOWERS AND FLURRIES WILL OCCUR ELSEWHERE WITH
LIGHT ACCUMULATIONS. A STRONG ARCTIC FRONT WILL DROP THROUGH THE
REGION LATE FRIDAY...BRINGING THE COLDEST AIR MASS SINCE LAST
WINTER. WIND CHILLS WILL BE DANGEROUSLY LOW...WELL BELOW
ZERO...SATURDAY THROUGH SATURDAY NIGHT. A MODERATING TREND IS
EXPECTED EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
315 AM UPDATE...
WANTED TO SEND OUT AN "EARLY" UPDATE TO REFLECT ON THE CURRENT
SITUATION REGARDING OUR LAKE EFFECT EVENT. WILL SEND OUT A
SEPARATE AFD FOR THE SHORT TERM PERIOD TO GO OVER THE DANGEROUS
COLD OVER THE WEEKEND. FIRST THINGS FIRST, THE LAKE EFFECT. SEE
OUR WEBSITE FOR OUR LATEST SNOWFALL MAP THAT I JUST POSTED.
WARNINGS AND ADVISORIES WILL REMAIN IN PLACE. I DID SHIFT THE
HEAVIER AXIS OF SNOW FARTHER NORTH, TO REFLECT RADAR TRENDS FROM
YESTERDAY EVENING THROUGH NOW. THE CHANGE WILL INCREASE AMOUNTS IN
WEST CENTRAL ONEIDA COUNTY QUITE A BIT, WHILE DROPPING OFF
SHARPLY TOWARD THE CITY OF UTICA. I KEPT NORTHERN ONONDAGA IN THE
HIGHER AMOUNTS AS WELL, ALTHOUGH THEY WILL PROBABLY END UP BEING
LOWER OVERALL THAN WEST CENTRAL ONEIDA. THE HIGHER TOTALS ACROSS
NORTHERN ONONDAGA COUNTY IS A REFLECTION OF WHAT WE EXPECT TO
COME, NOT UNDERSTANDING WE HAVEN`T SEE MUCH SNOW HERE YET. WHILE
THE FORECAST GOING FORECAST IS LARGELY UNCHANGED FROM THIS POINT
FORWARD, WE HAVEN`T SEE MUCH SNOW AT ALL FROM THE NEAR THE CITY
OF SYRACUSE SOUTH. THUS I HAVE ADJUSTED TOTALS DOWN ACROSS
SOUTHERN ONONDAGA/MADISON COUNTIES, ALONG WITH NORTHERN
CORTLAND/CHENANGO/OTSEGO.
WHILE THE BAND HAS BEEN MAINLY NORTH OF KSYR AND HAS EVEN WAVERED
BACK INTO NORTHERN ONEIDA, CONFIDENCE IS HIGH THAT THE BAND WILL
SINK SOUTH BETWEEN 09Z AND 12Z. THE LATEST HRRR AND RAP SOUNDINGS
SHOW A MEAN WIND OF 275 NOW, ABRUPTLY SHIFTING TOWARD 290 BY 12Z,
THEN LOCKING IN FOR THE REST OF THE DAY. KBUF RADAR SHOWS THE
WESTERN SIDE OF THE BAND NEAR KROC IS ALREADY SHOWING SIGNS OF
THIS CHANGE AND WILL FOLLOW. SO WHILE THE EVENT HAS PLAYED OUT
WELL THUS FAR ACROSS WEST CENTRAL ONEIDA COUNTY, MANY IN METRO
SYRACUSE AND ALONG THE THRUWAY MAY BE WONDERING WHAT LAKE SNOWS?
DON`T LET YOUR GUARD DOWN YET AS HEAVIER SNOWS WILL SHIFT SOUTH
TODAY. WITH INVERSION HEIGHTS GRADUALLY LOWERING TOWARD 5KFT BY
LATE AFTERNOON, THE OVERALL INTENSITY WILL BE HIGHEST THIS
MORNING, THEN A GRADUAL WEAKENING TREND INTO EARLY TONIGHT.
SNOWFALL RATES THROUGH MID MORNING WILL STILL BE IN THE 1 TO 2"+
RANGE. THE FLOW REMAINS AROUND 290-300 THROUGH 06Z TONIGHT, BEFORE
THE FLOW BACKS ENOUGH TOWARD THE SOUTHWEST TO LIFT THE BAND OUT OF
OUR AREA TOWARD DAYBREAK FRIDAY. IN ALL A WIDESPREAD, LONG
DURATION 6"+ LOOKS GOOD ACROSS MUCH OF CENTRAL NY, WITH CLOSER TO
1 1/2 FEET OVER WESTERN ONEIDA COUNTY. I CONTINUE TO MENTION BLOW
AND DRIFTING SNOW WITHIN AND NEAR THE SNOW BANDS THEMSELVES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
4 AM UPDATE...
OVERVIEW...SNOW SQUALLS LIKELY FRIDAY NIGHT ALONG AN ARCTIC FRONT
THAT WILL DELIVER BRUTAL COLD SATURDAY AND SATURDAY NIGHT, WHICH
WILL RIVAL WHAT WE SAW LAST FEBRUARY.
FRIDAY/FRIDAY NIGHT....MOST OF FRIDAY WILL BE QUIET WITH A
SOUTHWEST FLOW AHEAD OF AN ARCTIC FRONT. THIS FLOW WILL KEEP MOST
OF THE AREA DRY THROUGH THE DAYLIGHT HOURS. FRIDAY EVENING THE
ARCTIC FRONT WILL CROSS THE AREA BETWEEN 0Z AND 06Z SATURDAY. SNOW
SQUALLS LOOK LIKELY, WITH THE POTENTIAL FOR POOR VISIBILITY AND
SNOWFALL RATES OF MORE THAN AN INCH PER HOUR. MODEL SOUNDINGS SHOW
STEEP LAPSE RATES OF MORE THAN 8.0 C/KM UP THROUGH 650 MB! IN
ADDITION STRONG OMEGA (LIFT/RISING AIR IN THE ATMOSPHERE) IS FOUND
WITH PLENTY OF MOISTURE RIGHT IN THE SNOW GROWTH REGION. THINK BIG
FLAKES, HIGH EFFICIENCY OF ACCUMULATING SNOWS. WILL ADD CHANCE OF
HEAVY SNOW FOR THE FRIDAY EVENING FORECAST. SNOWFALL AMOUNTS OF A
FEW INCHES LIKELY BUT AGAIN IT WILL BE THE RATE OF FALL WHICH WILL
CAUSE POOR VISIBILITIES AND DANGEROUS ROADS.
SATURDAY/SATURDAY NIGHT...BRUTAL COLD. 850 TEMPS FALL TO BETWEEN
-28C AND -30C! "OFFICIAL" HIGHS SATURDAY WILL BE IN THE TEENS AT
MIDNIGHT FRIDAY NIGHT, WITH TEMPS FALLING INTO THE SINGLE DIGITS
BY SATURDAY AFTERNOON. SOME AREAS WILL LIKELY DROP BELOW ZERO FOR
TEMPS SATURDAY AFTERNOON, ESPECIALLY IN NY STATE! THIS ALONE IS
COLD BUT A PRESSURE GRADIENT BETWEEN AN OCEAN STORM AND HIGH
PRESSURE OVER THE MIDWEST WILL PRODUCE ENOUGH WIND FOR WIND CHILL
READINGS BETWEEN -10 AND -30. WE WILL CONTINUE TO HIGHLIGHT THE
HIGH CONFIDENCE FOR EXTREME COLD AND DANGEROUS WIND CHILLS IN OUR
HWO, ON SOCIAL MEDIA, AND IN OUR ONLINE BRIEFING PACKAGE FOUND AT
WEATHER.GOV/BGM UNDER WEATHER HAZARD BRIEFING AT THE BOTTOM OF THE
PAGE. LOWS SATURDAY NIGHT WILL BE BELOW ZERO EVERYWHERE, WITH -20
READINGS POSSIBLE IN OUR COLDER SPOTS. IMPRESSIVE COLD AND THE
ONLY SILVER LINING IS THE FACT IT WON`T LAST LONG. SEE BELOW FOR
MORE ON MILDER WEATHER NEXT WEEK.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
430 PM UPDATE...
ONLY SOME MODERATION IN TEMPERATURES EXPECTED SUNDAY AS ARCTIC
HIGH SLIDES EAST RIGHT OVER THE AREA BY LATE DAY. WINDS WILL BE
SIGNIFICANTLY LESS...YET WE START THE DAY WITH SUBZERO
TEMPERATURES SO VERY COLD ANYWAYS. STILL EXPECT SOME LAKE EFFECT,
THOUGH THIS WILL TEND TO BE DIMINISHING THROUGH THE DAY HAS THE
HIGH MOVES IN. HIGHS LOOK TO RANGE FROM THE SINGLE DIGITS THROUGH
MUCH OF THE CATSKILLS NORTH TO THE TUG HILL WITH LOW TO MID TEENS
ELSEWHERE.
PATTERN WILL BE PROGRESSIVE ENOUGH FOR CORE OF ARCTIC AIR TO MOVE
OUT EARLY NEXT WEEK WITH MORE SIGNIFICANT MODERATION BACK TO AT
LEAST SEASONAL. MODELS INDICATE THE NEXT UPPER TROUGH MOVING INTO
THE EAST WITH LOW PRESSURE DEVELOPMENT BUT THERE IS MODEL
DISAGREEMENT ON TIMING, TRACK, AND INTENSITY. FOR NOW, INDICATE
CHANCE OF SNOW IN GRIDS FOR MONDAY THROUGH WEDNESDAY BUT THERE IS A
CHANCE LOW COULD TRACK FAR ENOUGH WEST TO BRING RAIN TO SOME AREAS
AS EARLY AS TUESDAY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
LE SNOW BAND IS XPCTD TO DROP SWRD ACROSS RME AND STALL IN THE SYR
AREA FOR SVRL HRS TODAY. THIS WEILL BRING BRIEF IFR CONDS TO
RME...AND PROLONGED IFR CIGS AND VSBY TO SYR FOR MUCH OF THE DAY.
ELSEWHERE...SCT SNOW SHWRS WILL BRING BRIEF LWR CONDS BUT MUCH OF
THE DAY WILL BE VFR ELSEWHERE. BAND IS XPCTD TO LIFT NWRD LTR THIS
EVE LVG VFR CONDS AT ALL STATIONS.
.OUTLOOK...
FRI THRU SUN...VARIABLE CEILING AND VSBY RESTRICTIONS DUE TO
PERIODS OF WIDESPREAD LIGHT SNOW AND BANDS OF MORE INTENSE LAKE
EFFECT SNOW...ESPECIALLY NORTHERN HALF. LESS COVERAGE AND TIME
AFFECTED FOR THE SOUTHERN AREAS.
MON...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ016-017-044>046.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST FRIDAY FOR NYZ009-018-
036-037.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
415 AM EST THU FEB 11 2016
.SYNOPSIS...
LAKE EFFECT SNOW WILL BE HEAVY AT TIMES THROUGH TONIGHT IN PARTS
OF CENTRAL NEW YORK...GENERALLY SOUTHEAST OF LAKE ONTARIO.
SCATTERED SNOW SHOWERS AND FLURRIES WILL OCCUR ELSEWHERE WITH
LIGHT ACCUMULATIONS. A STRONG ARCTIC FRONT WILL DROP THROUGH THE
REGION LATE FRIDAY...BRINGING THE COLDEST AIR MASS SINCE LAST
WINTER. WIND CHILLS WILL BE DANGEROUSLY LOW...WELL BELOW
ZERO...SATURDAY THROUGH SATURDAY NIGHT. A MODERATING TREND IS
EXPECTED EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
315 AM UPDATE...
WANTED TO SEND OUT AN "EARLY" UPDATE TO REFLECT ON THE CURRENT
SITUATION REGARDING OUR LAKE EFFECT EVENT. WILL SEND OUT A
SEPARATE AFD FOR THE SHORT TERM PERIOD TO GO OVER THE DANGEROUS
COLD OVER THE WEEKEND. FIRST THINGS FIRST, THE LAKE EFFECT. SEE
OUR WEBSITE FOR OUR LATEST SNOWFALL MAP THAT I JUST POSTED.
WARNINGS AND ADVISORIES WILL REMAIN IN PLACE. I DID SHIFT THE
HEAVIER AXIS OF SNOW FARTHER NORTH, TO REFLECT RADAR TRENDS FROM
YESTERDAY EVENING THROUGH NOW. THE CHANGE WILL INCREASE AMOUNTS IN
WEST CENTRAL ONEIDA COUNTY QUITE A BIT, WHILE DROPPING OFF
SHARPLY TOWARD THE CITY OF UTICA. I KEPT NORTHERN ONONDAGA IN THE
HIGHER AMOUNTS AS WELL, ALTHOUGH THEY WILL PROBABLY END UP BEING
LOWER OVERALL THAN WEST CENTRAL ONEIDA. THE HIGHER TOTALS ACROSS
NORTHERN ONONDAGA COUNTY IS A REFLECTION OF WHAT WE EXPECT TO
COME, NOT UNDERSTANDING WE HAVEN`T SEE MUCH SNOW HERE YET. WHILE
THE FORECAST GOING FORECAST IS LARGELY UNCHANGED FROM THIS POINT
FORWARD, WE HAVEN`T SEE MUCH SNOW AT ALL FROM THE NEAR THE CITY
OF SYRACUSE SOUTH. THUS I HAVE ADJUSTED TOTALS DOWN ACROSS
SOUTHERN ONONDAGA/MADISON COUNTIES, ALONG WITH NORTHERN
CORTLAND/CHENANGO/OTSEGO.
WHILE THE BAND HAS BEEN MAINLY NORTH OF KSYR AND HAS EVEN WAVERED
BACK INTO NORTHERN ONEIDA, CONFIDENCE IS HIGH THAT THE BAND WILL
SINK SOUTH BETWEEN 09Z AND 12Z. THE LATEST HRRR AND RAP SOUNDINGS
SHOW A MEAN WIND OF 275 NOW, ABRUPTLY SHIFTING TOWARD 290 BY 12Z,
THEN LOCKING IN FOR THE REST OF THE DAY. KBUF RADAR SHOWS THE
WESTERN SIDE OF THE BAND NEAR KROC IS ALREADY SHOWING SIGNS OF
THIS CHANGE AND WILL FOLLOW. SO WHILE THE EVENT HAS PLAYED OUT
WELL THUS FAR ACROSS WEST CENTRAL ONEIDA COUNTY, MANY IN METRO
SYRACUSE AND ALONG THE THRUWAY MAY BE WONDERING WHAT LAKE SNOWS?
DON`T LET YOUR GUARD DOWN YET AS HEAVIER SNOWS WILL SHIFT SOUTH
TODAY. WITH INVERSION HEIGHTS GRADUALLY LOWERING TOWARD 5KFT BY
LATE AFTERNOON, THE OVERALL INTENSITY WILL BE HIGHEST THIS
MORNING, THEN A GRADUAL WEAKENING TREND INTO EARLY TONIGHT.
SNOWFALL RATES THROUGH MID MORNING WILL STILL BE IN THE 1 TO 2"+
RANGE. THE FLOW REMAINS AROUND 290-300 THROUGH 06Z TONIGHT, BEFORE
THE FLOW BACKS ENOUGH TOWARD THE SOUTHWEST TO LIFT THE BAND OUT OF
OUR AREA TOWARD DAYBREAK FRIDAY. IN ALL A WIDESPREAD, LONG
DURATION 6"+ LOOKS GOOD ACROSS MUCH OF CENTRAL NY, WITH CLOSER TO
1 1/2 FEET OVER WESTERN ONEIDA COUNTY. I CONTINUE TO MENTION BLOW
AND DRIFTING SNOW WITHIN AND NEAR THE SNOW BANDS THEMSELVES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
4 AM UPDATE...
OVERVIEW...SNOW SQUALLS LIKELY FRIDAY NIGHT ALONG AN ARCTIC FRONT
THAT WILL DELIVER BRUTAL COLD SATURDAY AND SATURDAY NIGHT, WHICH
WILL RIVAL WHAT WE SAW LAST FEBRUARY.
FRIDAY/FRIDAY NIGHT....MOST OF FRIDAY WILL BE QUIET WITH A
SOUTHWEST FLOW AHEAD OF AN ARCTIC FRONT. THIS FLOW WILL KEEP MOST
OF THE AREA DRY THROUGH THE DAYLIGHT HOURS. FRIDAY EVENING THE
ARCTIC FRONT WILL CROSS THE AREA BETWEEN 0Z AND 06Z SATURDAY. SNOW
SQUALLS LOOK LIKELY, WITH THE POTENTIAL FOR POOR VISIBILITY AND
SNOWFALL RATES OF MORE THAN AN INCH PER HOUR. MODEL SOUNDINGS SHOW
STEEP LAPSE RATES OF MORE THAN 8.0 C/KM UP THROUGH 650 MB! IN
ADDITION STRONG OMEGA (LIFT/RISING AIR IN THE ATMOSPHERE) IS FOUND
WITH PLENTY OF MOISTURE RIGHT IN THE SNOW GROWTH REGION. THINK BIG
FLAKES, HIGH EFFICIENCY OF ACCUMULATING SNOWS. WILL ADD CHANCE OF
HEAVY SNOW FOR THE FRIDAY EVENING FORECAST. SNOWFALL AMOUNTS OF A
FEW INCHES LIKELY BUT AGAIN IT WILL BE THE RATE OF FALL WHICH WILL
CAUSE POOR VISIBILITIES AND DANGEROUS ROADS.
SATURDAY/SATURDAY NIGHT...BRUTAL COLD. 850 TEMPS FALL TO BETWEEN
-28C AND -30C! "OFFICIAL" HIGHS SATURDAY WILL BE IN THE TEENS AT
MIDNIGHT FRIDAY NIGHT, WITH TEMPS FALLING INTO THE SINGLE DIGITS
BY SATURDAY AFTERNOON. SOME AREAS WILL LIKELY DROP BELOW ZERO FOR
TEMPS SATURDAY AFTERNOON, ESPECIALLY IN NY STATE! THIS ALONE IS
COLD BUT A PRESSURE GRADIENT BETWEEN AN OCEAN STORM AND HIGH
PRESSURE OVER THE MIDWEST WILL PRODUCE ENOUGH WIND FOR WIND CHILL
READINGS BETWEEN -10 AND -30. WE WILL CONTINUE TO HIGHLIGHT THE
HIGH CONFIDENCE FOR EXTREME COLD AND DANGEROUS WIND CHILLS IN OUR
HWO, ON SOCIAL MEDIA, AND IN OUR ONLINE BRIEFING PACKAGE FOUND AT
WEATHER.GOV/BGM UNDER WEATHER HAZARD BRIEFING AT THE BOTTOM OF THE
PAGE. LOWS SATURDAY NIGHT WILL BE BELOW ZERO EVERYWHERE, WITH -20
READINGS POSSIBLE IN OUR COLDER SPOTS. IMPRESSIVE COLD AND THE
ONLY SILVER LINING IS THE FACT IT WON`T LAST LONG. SEE BELOW FOR
MORE ON MILDER WEATHER NEXT WEEK.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
430 PM UPDATE...
ONLY SOME MODERATION IN TEMPERATURES EXPECTED SUNDAY AS ARCTIC
HIGH SLIDES EAST RIGHT OVER THE AREA BY LATE DAY. WINDS WILL BE
SIGNIFICANTLY LESS...YET WE START THE DAY WITH SUBZERO
TEMPERATURES SO VERY COLD ANYWAYS. STILL EXPECT SOME LAKE EFFECT,
THOUGH THIS WILL TEND TO BE DIMINISHING THROUGH THE DAY HAS THE
HIGH MOVES IN. HIGHS LOOK TO RANGE FROM THE SINGLE DIGITS THROUGH
MUCH OF THE CATSKILLS NORTH TO THE TUG HILL WITH LOW TO MID TEENS
ELSEWHERE.
PATTERN WILL BE PROGRESSIVE ENOUGH FOR CORE OF ARCTIC AIR TO MOVE
OUT EARLY NEXT WEEK WITH MORE SIGNIFICANT MODERATION BACK TO AT
LEAST SEASONAL. MODELS INDICATE THE NEXT UPPER TROUGH MOVING INTO
THE EAST WITH LOW PRESSURE DEVELOPMENT BUT THERE IS MODEL
DISAGREEMENT ON TIMING, TRACK, AND INTENSITY. FOR NOW, INDICATE
CHANCE OF SNOW IN GRIDS FOR MONDAY THROUGH WEDNESDAY BUT THERE IS A
CHANCE LOW COULD TRACK FAR ENOUGH WEST TO BRING RAIN TO SOME AREAS
AS EARLY AS TUESDAY.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
LE BAND WILL LINGER IN THE SYR/RME CORRIDOR AND BRING OCNL IFR
CONDS INTO THU. BAND IS XPCTD TO GRADUALLY SLIP SOPUTH AND WILL
BRING OCNL MVFR CIGS AND VSBYS TO ITH ANBD BGM LTR IN THE DAY.
WEAKENING FLOW AND DRIER AIR WILL ERODE THE LAKE EFFECT LVG GNRL
VFR CONDS TO ALL STATIONS AFT 00Z. GUSTY WEST WNDS TODAY WILL
BECOME LGTR AFT SUNSET THIS EVE.
.OUTLOOK...
THU NGT THROUGH SUN...VARIABLE CEILING AND VSBY RESTRICTIONS DUE
TO PERIODS OF WIDESPREAD LIGHT SNOW AND BANDS OF MORE INTENSE LAKE
EFFECT SNOW...ESPECIALLY NORTHERN HALF. LESS COVERAGE AND TIME
AFFECTED FOR THE SOUTHERN AREAS.
MON...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ016-017-044>046.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST FRIDAY FOR NYZ009-018-
036-037.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN
SHORT TERM...HEDEN
LONG TERM...MDP
AVIATION...DGM/PCF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
320 AM EST THU FEB 11 2016
.SYNOPSIS...
LAKE EFFECT SNOW WILL BE HEAVY AT TIMES TONIGHT THROUGH THURSDAY
IN PARTS OF CENTRAL NEW YORK...GENERALLY SOUTHEAST OF LAKE
ONTARIO. SCATTERED SNOW SHOWERS AND FLURRIES WILL OCCUR ELSEWHERE
WITH LIGHT ACCUMULATIONS. A STRONG ARCTIC FRONT WILL DROP THROUGH
THE REGION LATE FRIDAY...BRINGING THE COLDEST AIR MASS SINCE LAST
WINTER. WIND CHILLS WILL BE DANGEROUSLY LOW...WELL BELOW
ZERO...SATURDAY THROUGH SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
315 AM UPDATE...
WANTED TO SEND OUT AN "EARLY" UPDATE TO REFLECT ON THE CURRENT
SITUATION REGARDING OUR LAKE EFFECT EVENT. WILL SEND OUT A
SEPARATE AFD FOR THE SHORT TERM PERIOD TO GO OVER THE DANGEROUS
COLD OVER THE WEEKEND. FIRST THINGS FIRST, THE LAKE EFFECT. SEE
OUR WEBSITE FOR OUR LATEST SNOWFALL MAP THAT I JUST POSTED.
WARNINGS AND ADVISORIES WILL REMAIN IN PLACE. I DID SHIFT THE
HEAVIER AXIS OF SNOW FARTHER NORTH, TO REFLECT RADAR TRENDS FROM
YESTERDAY EVENING THROUGH NOW. THE CHANGE WILL INCREASE AMOUNTS IN
WEST CENTRAL ONEIDA COUNTY QUITE A BIT, WHILE DROPPING OFF
SHARPLY TOWARD THE CITY OF UTICA. I KEPT NORTHERN ONONDAGA IN THE
HIGHER AMOUNTS AS WELL, ALTHOUGH THEY WILL PROBABLY END UP BEING
LOWER OVERALL THAN WEST CENTRAL ONEIDA. THE HIGHER TOTALS ACROSS
NORTHERN ONONDAGA COUNTY IS A REFLECTION OF WHAT WE EXPECT TO
COME, NOT UNDERSTANDING WE HAVEN`T SEE MUCH SNOW HERE YET. WHILE
THE FORECAST GOING FORECAST IS LARGELY UNCHANGED FROM THIS POINT
FORWARD, WE HAVEN`T SEE MUCH SNOW AT ALL FROM THE NEAR THE CITY
OF SYRACUSE SOUTH. THUS I HAVE ADJUSTED TOTALS DOWN ACROSS
SOUTHERN ONONDAGA/MADISON COUNTIES, ALONG WITH NORTHERN
CORTLAND/CHENANGO/OTSEGO.
WHILE THE BAND HAS BEEN MAINLY NORTH OF KSYR AND HAS EVEN WAVERED
BACK INTO NORTHERN ONEIDA, CONFIDENCE IS HIGH THAT THE BAND WILL
SINK SOUTH BETWEEN 09Z AND 12Z. THE LATEST HRRR AND RAP SOUNDINGS
SHOW A MEAN WIND OF 275 NOW, ABRUPTLY SHIFTING TOWARD 290 BY 12Z,
THEN LOCKING IN FOR THE REST OF THE DAY. KBUF RADAR SHOWS THE
WESTERN SIDE OF THE BAND NEAR KROC IS ALREADY SHOWING SIGNS OF
THIS CHANGE AND WILL FOLLOW. SO WHILE THE EVENT HAS PLAYED OUT
WELL THUS FAR ACROSS WEST CENTRAL ONEIDA COUNTY, MANY IN METRO
SYRACUSE AND ALONG THE THRUWAY MAY BE WONDERING WHAT LAKE SNOWS?
DON`T LET YOUR GUARD DOWN YET AS HEAVIER SNOWS WILL SHIFT SOUTH
TODAY. WITH INVERSION HEIGHTS GRADUALLY LOWERING TOWARD 5KFT BY
LATE AFTERNOON, THE OVERALL INTENSITY WILL BE HIGHEST THIS
MORNING, THEN A GRADUAL WEAKENING TREND INTO EARLY TONIGHT.
SNOWFALL RATES THROUGH MID MORNING WILL STILL BE IN THE 1 TO 2"+
RANGE. THE FLOW REMAINS AROUND 290-300 THROUGH 06Z TONIGHT, BEFORE
THE FLOW BACKS ENOUGH TOWARD THE SOUTHWEST TO LIFT THE BAND OUT OF
OUR AREA TOWARD DAYBREAK FRIDAY. IN ALL A WIDESPREAD, LONG
DURATION 6"+ LOOKS GOOD ACROSS MUCH OF CENTRAL NY, WITH CLOSER TO
1 1/2 FEET OVER WESTERN ONEIDA COUNTY. I CONTINUE TO MENTION BLOW
AND DRIFTING SNOW WITHIN AND NEAR THE SNOW BANDS THEMSELVES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
430 PM UPDATE...
MAIN ATTENTION TURNS TO A SIGNIFICANT BLAST OF ARCTIC AIR...THE
COLDEST SINCE LAST WINTER...WHICH WILL PRODUCE DANGEROUSLY LOW
WIND CHILLS BY SATURDAY.
BEFORE THAT...LAKE EFFECT SNOW WILL CONTINUE INTO THURSDAY
EVENING ACROSS THE WARNING ZONES...BUT OVERNIGHT THE LOW LEVEL
FLOW WILL BACK WELL AHEAD OF NEXT FRONT...WHICH WILL DIMINISH AND
SHIFT LAKE EFFECT SNOW NORTH OF THE AREA.
FRIDAY...SURFACE LOW WILL TRACK FROM THE UPPER GREAT LAKES EAST
ACROSS NEARBY SOUTHERN CANADA AND DRAG AN ARCTIC FRONT THROUGH THE
REGION FRIDAY EVENING. THE FRONT LOOKS PRIMED TO PICK UP GREAT
LAKES MOISTURE AS IT DROPS. IT LOOKS QUITE PROBABLE THAT THE FRONT
WILL BE ACCOMPANIED BY A PRETTY STOUT SNOW SQUALL FRIDAY EVENING.
WHILE IT MAY ONLY PRODUCE A QUICK INCH OR SO OF ACCUMULATION...IT
WILL LIKELY COME DOWN VERY ABRUPTLY.
FORECAST MODELS IN GREAT OVERALL AGREEMENT ON 500 MB TROUGH AND
ASSOCIATED UPPER LOW DROPPING INTO THE NORTHEAST WITH 1000-500 MB
THICKNESS PROGGED TO ONLY BE AROUND 490 DM AND 850 MB TEMPS AROUND
-30 C...ABOUT AS COLD AS IS SEEN AROUND HERE. VERY RUDE AWAKENING
SATURDAY MORNING...WITH WIND CHILLS ALREADY WELL BELOW ZERO...AND
ACTUAL TEMPERATURES MAINLY SINGLE DIGITS AND FALLING THROUGH THE
DAY. WIND CHILLS TEENS-20S BELOW ZERO ARE FIGURED BY SATURDAY
AFTERNOON...SOME PLACES EVEN COLDER SATURDAY NIGHT. UNPROTECTED
VULNERABLE PLUMBING MAY EXPERIENCE FREEZING/BREAKING...AND ANYONE
NOT TAKING PROPER PRECAUTIONS OUTSIDE COULD EXPERIENCE FROSTBITE
HYPOTHERMIA. THIS ARCTIC AIR MASS SHOULD BE TAKEN SERIOUSLY.
DENDRITIC GROWTH LAYER WILL ACTUALLY CRASH TO THE GROUND IN THIS
ARCTIC AIR MASS...SO LAKE EFFECT WILL BE LIMITED YET DRY FLUFFY
FLURRIES CAN BE EXPECTED OUT OF JUST ABOUT ANY CLOUD.
SATURDAY NIGHT WILL BE THE COLDEST NIGHT WITH WIDESPREAD SUBZERO
LOWS EXPECTED...POSSIBLY EVEN MINUS DOUBLE DIGIT LOWS...ESPECIALLY
IN EASTERN ZONES NORTH THROUGH ONEIDA COUNTY. WINDS LOOK TO STAY
UP DUE TO CONTINUING GRADIENT BETWEEN LOW TO THE EAST AND HIGH TO
THE WEST AND THIS WILL MAKE IT FEEL EVEN COLDER BUT MAY ACT TO
LIMIT TEMPS FROM BOTTOMING OUT TO REALLY EXTREME VALUES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
430 PM UPDATE...
ONLY SOME MODERATION IN TEMPERATURES EXPECTED SUNDAY AS ARCTIC
HIGH SLIDES EAST RIGHT OVER THE AREA BY LATE DAY. WINDS WILL BE
SIGNIFICANTLY LESS...YET WE START THE DAY WITH SUBZERO
TEMPERATURES SO VERY COLD ANYWAYS. STILL EXPECT SOME LAKE EFFECT,
THOUGH THIS WILL TEND TO BE DIMINISHING THROUGH THE DAY HAS THE
HIGH MOVES IN. HIGHS LOOK TO RANGE FROM THE SINGLE DIGITS THROUGH
MUCH OF THE CATSKILLS NORTH TO THE TUG HILL WITH LOW TO MID TEENS
ELSEWHERE.
PATTERN WILL BE PROGRESSIVE ENOUGH FOR CORE OF ARCTIC AIR TO MOVE
OUT EARLY NEXT WEEK WITH MORE SIGNIFICANT MODERATION BACK TO AT
LEAST SEASONAL. MODELS INDICATE THE NEXT UPPER TROUGH MOVING INTO
THE EAST WITH LOW PRESSURE DEVELOPMENT BUT THERE IS MODEL
DISAGREEMENT ON TIMING, TRACK, AND INTENSITY. FOR NOW, INDICATE
CHANCE OF SNOW IN GRIDS FOR MONDAY THROUGH WEDNESDAY BUT THERE IS A
CHANCE LOW COULD TRACK FAR ENOUGH WEST TO BRING RAIN TO SOME AREAS
AS EARLY AS TUESDAY.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
LE BAND WILL LINGER IN THE SYR/RME CORRIDOR AND BRING OCNL IFR
CONDS INTO THU. BAND IS XPCTD TO GRADUALLY SLIP SOPUTH AND WILL
BRING OCNL MVFR CIGS AND VSBYS TO ITH ANBD BGM LTR IN THE DAY.
WEAKENING FLOW AND DRIER AIR WILL ERODE THE LAKE EFFECT LVG GNRL
VFR CONDS TO ALL STATIONS AFT 00Z. GUSTY WEST WNDS TODAY WILL
BECOME LGTR AFT SUNSET THIS EVE.
.OUTLOOK...
THU NGT THROUGH SUN...VARIABLE CEILING AND VSBY RESTRICTIONS DUE
TO PERIODS OF WIDESPREAD LIGHT SNOW AND BANDS OF MORE INTENSE LAKE
EFFECT SNOW...ESPECIALLY NORTHERN HALF. LESS COVERAGE AND TIME
AFFECTED FOR THE SOUTHERN AREAS.
MON...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR
NYZ016-017-044>046.
LAKE EFFECT SNOW WARNING UNTIL 4 AM EST FRIDAY FOR NYZ009-018-
036-037.
&&
$$
SYNOPSIS...RRM
NEAR TERM...HEDEN
SHORT TERM...MDP
LONG TERM...MDP
AVIATION...DGM/PCF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
940 PM EST FRI FEB 12 2016
.SYNOPSIS...ARCTIC HIGH PRESSURE WILL BUILD OVER THE REGION OVER THE
WEEKEND. A DEVELOPING STORM SYSTEM WILL APPROACH FROM THE WEST
SUNDAY NIGHT AND THEN MOVE EASTWARD THROUGH THE AREA MONDAY THROUGH
TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 PM FRIDAY...
STARTING TO FINALLY SEE BETTER WEST TO EAST CLEARING OF MOISTURE
AROUND 6000-7000 FT AS A JET ON THE BACK SIDE OF THE UPPER TROUGH
APPROACHES AND NORTHWEST FLOW STRENGTHENS. LOW-LEVEL MOISTURE IS
STILL MORE PREVALENT ON THE COASTAL PLAIN WHERE SOME SUB-1000 FT
STRATUS IS LINGERING. A PERIOD OF PATCHY FOG MAY DEVELOP IN THE
SOUTHERN COASTAL PLAIN AS THE HIGHER LEVEL CLOUDS CLEARING (HINTED AT
BY SREF PROBS AND KFAY/KGSB RAP SOUNDINGS)...BUT IT WOULD LIKELY BE
BRIEF...PRIOR TO 06Z...WITH A NORTHWEST WIND AND COLD ADVECTION
FORECAST TO SLOWLY STRENGTHEN AFTER MIDNIGHT. OTHERWISE...WHILE WE
MAY SEE A SOME PATCHES OF STRATOCU DRIFT ACROSS THE AREA GIVEN ALL
THE MOISTURE BANKED UPSTREAM OF THE MOUNTAINS...CLEARING SKIES AND
COLD ADVECTION WILL PUSH LOWS INTO THE LOWER 20S NORTH AND WEST TO
UPPER 20S SOUTH AND EAST.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...
AS EAST COAST TROUGH TRIES TO PULL OFF THE COAST...VERY STRONG COLD
AIR ADVECTION WILL ENSUE BEHIND THE EXITING COASTAL SYSTEM. WITH
VERY STRONG PRESSURE GRADIENT ACROSS THE AREA...COLD TEMPERATURES
AND STRONG WINDS WILL BE THE FORECAST PROBLEM OF THE DAY. EXPECT
WINDS TO REMAIN SUSTAINED OUT OF THE NORTH OR NORTHWEST AT 10-15 KTS
WITH GUSTS OF 25-30 KTS FOR MUCH OF THE DAYLIGHT HOURS. AFTER SUNSET
GUSTS WILL SUBSIDE. HIGH TEMPERATURES ONLY IN THE LOW TO MID 30S AND
WITH WIND CHILL VALUES IN THE UPPER 10S TO LOW 20S FOR MUCH OF THE
DAY. AS AN ASIDE...WITH THE COLD BUT ALSO DRY AIRMASS IN PLACE...MIN
RH VALUES WILL DIP DOWN INTO THE LOW 20S. COMBINE THESE VALUES WITH
THE HIGHER WINDS AND THERE WILL BE A SMALL INCREASE IN FIRE DANGER
SATURDAY IN OUR SOUTHERN COUNTIES THAT MAY SQUEAK INTO THE LOWER
40S.
SATURDAY NIGHT WILL SEE THE GUSTS SLACK OFF BUT SUSTAINED WINDS TO
REMAIN UP IN THE 5 TO 10 KT RANGE KEEP THINGS MIXED A LITTLE.
COMBINE THIS WITH VERY COLD EXPECTED LOW TEMPERATURES IN THE LOW TO
MID TEENS...WIND CHILL VALUES SATURDAY NIGHT WILL RESIDE IN THE 5-10
DEGREE RANGE. PREPARATIONS SHOULD BE MADE NOW TO PROTECT ANYTHING
SUSCEPTIBLE TO THE COLD WIND CHILLS...ESPECIALLY PETS. SOME CLOUDS
WILL BEGIN TO APPROACH THE AREA LATE SATURDAY NIGHT INTO SUNDAY
MORNING FROM THE WEST IN ADVANCE OF THE NEXT STORM SYSTEM.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 315 PM FRIDAY...
...STORM SYSTEM LIKELY TO BRING WINTRY WEATHER THREAT SUN NIGHT/MON
FOLLOWED BY HEAVY RAIN THREAT AND A FEW STORMS MON NIGHT/TUE...
SUNDAY: CONTINUED CHILLY WITH THE ARCTIC HIGH PRESSURE EXTENDING
FROM THE ERN GREAT LAKES DOWN THROUGH NC. WILL HAVE INCREASING
CLOUDS AHEAD OF THE APPROACHING STORM... AS OUR MID LEVEL FLOW
SHIFTS FROM FAST NORTHWESTERLY TO WEST-SOUTHWEST... A FUNCTION OF
PACIFIC NORTHWEST ENERGY DIVING INTO AN INITIALLY FLAT/BROAD CENTRAL
CONUS TROUGH CAUSING ITS AMPLIFICATION. STATISTICAL GUIDANCE STILL
SUPPORTS HIGHS FROM 29 NE TO 35 SW. -GIH
SUN NIGHT THROUGH TUE:
OVERVIEW: CONFIDENCE IS BEGINNING TO INCREASE REGARDING THE
TIMING... MOST PROBABLE PRECIP TYPE PATTERN... AND PRIMARY WEATHER
THREATS FOR THE INCOMING SYSTEM. LATEST GUIDANCE SHOWS A BIT QUICKER
ONSET... WITH PRECIP ARRIVING IN THE NRN/WRN CWA SUN NIGHT... AS
WELL AS A SLIGHTLY EARLIER DEPARTURE ON TUE. LONGWAVE TROUGHING WILL
CONTINUE TO AMPLIFY ALONG THE MISS VALLEY AS NRN STREAM ENERGY DROPS
INTO ITS BASE OVER THE GULF STATES... CULMINATING IN A NARROW DEEP
SHORTWAVE TROUGH TAKING ON A POSITIVE TILT AS IT SWINGS ENE INTO THE
CAROLINAS. AT THE SURFACE... THE POLAR HIGH SITUATED OVER THE
NORTHEAST AND MIDATLANTIC STATES SUN NIGHT CONTINUES TO PUSH
STEADILY NORTHEAST AND OFFSHORE THROUGH MON... WHILE A COASTAL FRONT
FORMS ALONG THE CAROLINA COAST EXTENDING BACK TO DEVELOPING LOW
PRESSURE OVER THE CENTRAL GULF STATES. THIS LOW THEN TRACKS EAST
THEN NE THROUGH WRN NC MON NIGHT/TUE MORNING BEFORE MOVING QUICKLY
INTO THE NORTHEAST STATES... WITH A TRAILING FRONT SWEEPING THROUGH
CENTRAL/ERN NC BY EARLY TUE AFTERNOON.
PRECIPITATION CHANCES: THE INITIAL PROCESSES TO FORCE ASCENT SUNDAY
NIGHT INTO EARLY MONDAY INCLUDING DPVA AND MOIST ISENTROPIC UPGLIDE
ARE RATHER WEAK AND FOCUSED PRIMARILY ON WRN AND NRN PORTIONS OF
CENTRAL NC. WILL TREND POPS UP TO LIKELY NW AND RETAIN HIGH CHANCES
ACROSS THE SOUTH AND EAST SUN NIGHT INTO MON MORNING... WITH QPF
FAIRLY LIGHT... UNDER A QUARTER INCH MAINLY IN THE NW. BUT THIS
CHANGES QUICKLY WITH THE ADDITION OF STRONG UPPER DIVERGENCE (DUE TO
IDEALLY JUXTAPOSED POLAR AND SUBTROPICAL JETS) AND VIGOROUS LOW
LEVEL MOISTURE TRANSPORT EAST OF THE LOW. WILL RAMP UP POPS FURTHER
TO CATEGORICAL WEST/LIKELY EAST LATE MON... THEN TO CATEGORICAL
EVERYWHERE MON NIGHT THROUGH TUE MORNING... ENDING SW TO NE TUE
AFTERNOON.
PTYPES: USING THE TOP-DOWN METHODOLOGY WITH CONSIDERATION OF THE
INITIALLY VERY COLD/DENSE NATURE OF THE SURFACE AIR MASS... THE
INITIAL COLD AIR ALOFT GIVING WAY TO A WARM NOSE... AND THE STRONG
LOW LEVEL WARM ADVECTION APT TO DISLODGE THIS SURFACE AIR MASS
GRADUALLY FROM SE TO NW MON EVENING... EXPECT THIS TO START AS
MOSTLY LIGHT SNOW WITH PERHAPS PATCHY LIGHT SLEET SUN NIGHT ACROSS
THE NRN AND WRN CWA... FOLLOWED BY A SLOW STEADY TRANSITION FROM SSE
TO NNW TO FREEZING RAIN/SLEET THEN TO ALL RAIN... WITH THE FAR NW
COUNTIES INCLUDING THE TRIAD THE LAST TO SEE AN END TO THE WINTRY
PRECIP MON EVENING. TENTATIVE ACCUMULATIONS ARE UP TO ONE TO TWO
HUNDREDTHS OF AN INCH OF ICING (TRACE AMOUNTS) FOR MUCH OF THE
CWA... AND SNOW TOTALS OF 1-3" NW QUARTER WITH AN INCH OR LESS
ELSEWHERE... ALL OF WHICH SHOULD BE QUICKLY SWEPT AWAY BY MODERATE
TO POTENTIALLY HEAVY RAINFALL LATE MON NIGHT INTO TUE MORNING.
RAINFALL TOTALS AND STORM POTENTIAL: AT THIS TIME STORM TOTAL LIQUID
QPF IS EXPECTED TO BE 1-2" WITH LOCALLY HIGHER AMOUNTS POSSIBLE...
GIVEN THE HIGH WATER CONTENT AND STRONG LIFT MON NIGHT/TUE MORNING.
BASED ON THE ANTECEDENT CONDITIONS AND SEVERAL RIVERS AND CREEKS
RUNNING HIGH... A FLOOD WATCH MAY BE NEEDED FOR SOME PORTION OF THE
AREA. ALSO... WHILE LAPSE RATES ARE UNLIKELY TO BE VERY
IMPRESSIVE... THE STRONG AND FOCUSED LIFT POSSIBLE WITH THIS SYSTEM
AND WARMING LOW LEVELS ESPECIALLY IN THE SANDHILLS AND COASTAL PLAIN
MAY SUPPORT A FEW LIGHTNING STRIKES ON TUE.
TEMPS: EXPECT LOWS SUN NIGHT OF 22-26. TEMPS SHOULD SLOWLY RISE MON
THROUGH MON NIGHT... REACHING THE LOW 30S NW TO LOW 40S SE LATE
MON... RISING TO THE MID 30S NW TO MID 40S SE MON NIGHT... AND
PEAKING AT 48-56 TUE PRIOR TO FRONTAL PASSAGE.
WED THROUGH FRI: WE MAY SEE A PERTURBATION SWING THROUGH THE
LONGWAVE ERN TROUGH BASE ACROSS VA ON WED... BUT MODELS VARY ON THE
STRENGTH AND LATITUDE OF ANY SUCH WAVE... AND REGARDLESS THE
MOISTURE WILL BE LIMITED YIELDING NO IMPACTS ON CENTRAL NC OTHER
THAN SOME CLOUDS ACROSS THE NORTH. OTHERWISE... THIS PERIOD WILL
FEATURE A TRANSITION AWAY FROM WRN RIDGE/ERN TROUGH OVER THE
CONUS... AS FLAT RIDGING BUILDS OVER THE GULF/SOUTHEAST STATES FROM
THE WEST... WITH A NET RESULT OF DRY WEATHER AND NEAR TO SLIGHTLY
ABOVE NORMAL TEMPS FOR CENTRAL NC. -GIH
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 730 PM FRIDAY...
24 HOUR TAF PERIOD: ASIDE FROM LINGERING IFR/MVFR CEILINGS THROUGH 01-
02Z AT THE FAY TERMINAL...VFR CONDITIONS WILL PREVAIL AT ALL
TERMINALS FOR THE DURATION OF THE TAF PERIOD. THE ONLY AVIATION
CONCERN WILL BE GUSTY NORTHWEST WINDS DURING THE DAY SATURDAY (ESP
MORNING)...IN THE WAKE OF AN ARCTIC COLD FRONTAL PASSAGE LATE
TONIGHT. EXPECT WINDS TO INCREASE TO ~15 KT WITH GUSTS UP TO 25 KT
DURING THE STRONGEST COLD ADVECTION (09-15Z)...REMAINING STEADY AT
12-16 KT FOR THE REMAINDER OF THE DAY. WINDS WILL DECREASE TO 5-10
KT AFTER SUNSET SAT EVENING.
LOOKING AHEAD: VFR CONDITIONS WILL PREVAIL THROUGH MID-DAY SUNDAY AS
AN ARCTIC AIRMASS ADVECTS INTO/OVER THE REGION. HIGH PRESSURE WILL
QUICKLY MOVE OFFSHORE...WITH MVFR CEILINGS RETURNING FROM WEST-EAST
SUNDAY EVENING/NIGHT IN ASSOC/W A STRENGTHENING SOUTHERLY RETURN
FLOW. CONFIDENCE IN THE FORECAST DECREASES SIGNIFICANTLY EARLY NEXT
WEEK...HOWEVER...ADVERSE CONDITIONS IN THE FORM OF LOW CEILINGS AND
PRECIPITATION (PERHAPS MIXED PTYPE) WILL BE POSSIBLE. -VINCENT
&&
.CLIMATE...
HERE ARE THE RECORD LOWS AND RECORD LOW MAXIMUM TEMPERATURES FOR SAT
FEB 13TH AND SUN FEB 14TH AT GSO... RDU... AND FAY:
REC YR REC YR
LOW LOW MAX
----------------------------------------------
GSO:
02/13 11 1955 31 1986
02/14 6 1905 22 1914
RDU:
02/13 4 1899 10 1899
02/14 -2 1899 27 1916
FAY:
02/13 14 1973 32 1955
02/14 12 1968 33 1916
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...SMITH
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...VINCENT
CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1145 PM CST WED FEB 10 2016
.UPDATE...
ISSUED AT 1145 PM CST WED FEB 10 2016
REGIONAL RADAR SHOWS REFLECTIVITYS INCREASING ACROSS SOUTHWEST
SASKATCHEWAN AND INTO EASTERN MONTANA. SOME ENHANCEMENT ALSO
SHOWING UP IN NORTHWEST NORTH DAKOTA. 00Z MODEL GUIDANCE IN GOOD
AGREEMENT WITH LIGHT SNOW DEVELOPING NORTHWEST TO SOUTHEAST
OVERNIGHT. THUS LIGHT SNOW WILL BE INTO WILLISTON WITHIN THE NEXT
HOUR OR TWO...AND THEN INTO BISMARCK AROUND 6AM CST THURSDAY.
THE LEFT EXIT REGION OF A JET STREAK PROPAGATING ACROSS CENTRAL
MONTANA WILL PROVIDE LARGE SCALE ASCENT UNTIL MID AFTERNOON
THURSDAY. THUS LIKELY TO CATEGORICAL POPS WEST AND SOUTH CENTRAL
LATE TONIGHT INTO THURSDAY. NAM/RAP/HRRR BUFKIT SOUNDINGS ALL
POINT TO A QUICK SATURATION THROUGH THE COLUMN OVERNIGHT. THUS
RISK OF PATCHY LIGHT FREEZING DRIZZLE WILL WANE FROM WEST TO EAST
THROUGH 12Z THURSDAY.
UPDATE ISSUED AT 932 PM CST WED FEB 10 2016
MAIN UPDATE LATE THIS EVENING WAS TO ADD A MENTION OF PATCHY
FREEZING DRIZZLE BACK TO THE FORECAST THIS EVENING. LOWER LAYERS
HAVE BEEN MOISTENING UP ACROSS THE NORTHWEST INTO THE WEST
CENTRAL. ALSO RECEIVED A REPORT OF LIGHT FREEZING DRIZZLE AT
GRASSY BUTTE. LATEST RAP BUFKIT SOUNDINGS DO SUPPORT A PERIOD OF
DRIZZLE MAINLY BEFORE MIDNIGHT ACROSS THIS AREA...BEFORE THE
ENTIRE COLUMN MOISTENS. THUS ADDED A MENTION BACK TO THE NORTHWEST
THROUGH 06Z AND THEN SHIFTED IT INTO THE SOUTHWEST THROUGH 09Z.
TEMPERATURES LOOK REASONABLE. ROLLA IN THE FAR NORTH CENTRAL HAS
DROPPED TO ZERO IN A SMALL CLEAR PATCH AND COULD DROP A FEW MORE
DEGREES. TREND THOUGH IS FOR STEADY OR SLOWLY RISING TEMPERATURES
AS CLOUDS INCREASE FROM THE WEST.
UPDATE ISSUED AT 637 PM CST WED FEB 10 2016
SURFACE LOW PRESSURE THAT MOVED THROUGH THE AREA LAST NIGHT INTO
TODAY HAS MOVED WELL SOUTH. HIGH PRESSURE CONTINUES TO DROP SOUTH
FROM MANITOBA INTO EASTERN NORTH DAKOTA AND MINNESOTA...WHILE A
LEE SIDE TROUGH IS TAKING SHAPE OVER THE NORTHERN AND CANADIAN
ROCKIES.
THE SURFACE TROUGH WILL MOVE INTO EASTERN MONTANA TONIGHT AND
COMBINED WITH SHORTWAVE ENERGY ALONG THE BAROCLINIC ZONE WILL
PRODUCE LIGHT SNOW WHICH IS EXPECTED TO SPREAD INTO WESTERN
NORTH DAKOTA AFTER MIDNIGHT. UNTIL THEN...T/TD SPREAD REMAIN
PRETTY HIGH ACROSS THE WEST WITH WIDESPREAD STRATUS OVER ALL BUT
THE FAR SOUTHWEST CORNER OF THE STATE. THUS THINK THE RISK OF
FREEZING DRIZZLE THIS EVENING IS MINIMAL. AS WE HEAD INTO THE
OVERNIGHT HOURS...MOISTURE INCREASES THROUGHOUT THE ATMOSPHERIC
COLUMN AND DRY LAYERS ALOFT...CONDUCIVE TO DRIZZLE QUICKLY MOISTEN
UP. THUS HAVE ALSO REMOVED THE MENTION OF DRIZZLE AFTER MIDNIGHT.
WILL KEEP A MENTION OF FOG AS SURFACE MOISTURE WILL INCREASE AS
WE MOVE INTO THE OVERNIGHT HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 254 PM CST WED FEB 10 2016
CURRENT SURFACE ANALYSIS PLACES LOW/BOUNDARY STRETCHING THROUGH
WESTERN NORTH DAKOTA INTO CENTRAL SOUTH DAKOTA/NEBRASKA WHILE HIGH
REMAINS OVER THE GREAT BASIN. UPPER LEVEL ANALYSIS PLACES BROAD RIDGE
OVER THE WESTERN CONUS WITH BROAD TROUGH OVER THE EASTERN CONUS
BRINGING FAST NORTHWESTERLY FLOW OVER OUR AREA. SOME LIGHT SNOW
LINGERS OVER EASTERN PORTIONS OF THE AREA AS RIGHT ENTRANCE REGION
OF AN UPPER JET STREAK WORKS ITS WAY OFF TO THE SOUTHEAST.
FOR THE REST OF THIS AFTERNOON INTO TONIGHT...SOME LIGHT SNOW MAY
LINGER OVER THE EASTERN PART OF THE AREA THROUGH THE AFTERNOON AS
THE AFOREMENTIONED JET CONTINUES ON ITS WAY. CLOUDY CONDITIONS
WILL REMAIN OVER THE AREA...WHILE OVER THE SOUTHWEST LATEST
FORECAST SOUNDINGS SUGGEST SOME FOG WITH PATCHY FREEZING DRIZZLE
MAY DEVELOP. LATER TONIGHT BROAD SHORT WAVE MOVES INTO THE REGION
RESULTING IN AN ELONGATED AREA OF MODEST LIFT OVER WESTERN PARTS
OF NORTH DAKOTA. THEREFORE...EXPECT SOME LIGHT SNOW TO DEVELOP AND
GRADUALLY SPREAD SOUTHERLY.
FOR THURSDAY...BROAD AREA OF MODEST LIFT SPREADS EASTERLY INTO
CENTRAL PARTS OF NORTH DAKOTA WITH THE GREATEST CHANCES FOR SNOW
SPREADING FROM WEST CENTRAL TO SOUTH CENTRAL PORTIONS OF THE
STATE WHERE A BROAD SWATH OF 1 TO 3 INCHES MAY FALL. OVER THE FAR
SOUTHWEST...WARMER CONDITIONS MAY LEAD TO PERIODS OF RAIN
DEVELOPING BY MID-DAY INTO THE AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 254 PM CST WED FEB 10 2016
AN ACTIVE WEATHER PATTERN CONTINUES THROUGH THE LONG TERM.
NORTHWEST FLOW WILL CONTINUE INTO THE WEEKEND. THIS WILL BRING
SEVERAL WAVES ACROSS THE REGION.
THE FIRST WAVE IS EXPECTED TO ARRIVE THURSDAY. AS THE BAROCLINIC
ZONE SHIFTS WEST...SNOW WILL LIKELY OVERSPREAD WESTERN AND SOUTH
CENTRAL NORTH DAKOTA. HOWEVER...ONLY MINOR ACCUMULATIONS ARE
EXPECTED...GENERALLY AROUND ONE INCH.
THE NEXT WAVE IS EXPECTED TO IMPACT NORTH DAKOTA BEGINNING FRIDAY
NIGHT AND PERSIST THROUGH SUNDAY MORNING. THIS WAVE IS EXPECTED TO
BRING A LITTLE MORE MOISTURE TO THE REGION THAN PREVIOUS SYSTEMS
AS THIS WAVE WILL HAVE MORE OF A PACIFIC COMPONENT TO IT. WHILE
FORCING DOES NOT APPEAR TOO STRONG WITH THIS WAVE...PERSISTENT
LIGHT SNOW WITH BROAD SCALE LIFT OVER A 36 HOUR PERIOD COULD
BRING SNOWFALL AMOUNTS INTO THE 2 TO 4 INCH RANGE. MODELS ARE JUST
BEGINNING TO COME INTO BETTER AGREEMENT ON THE EVOLUTION OF THIS
SYSTEM...SO DETAILS WILL BE FURTHER REFINED OVER THE NEXT COUPLE
OF DAYS AND AMOUNTS/PRECIP TYPE COULD CHANGE QUITE A BIT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1145 PM CST WED FEB 10 2016
LIGHT SNOW AND FOG WILL RESULT IN CIGS/VSBYS TO DETERIORATE INTO
THE IFR/LIFR RANGE AT KISN/KDIK/KBIS 06Z-12Z THURSDAY AND
CONTINUE UNTIL AROUND 00Z FRIDAY. KMOT AND KJMS WILL REMAIN ON
THE EASTERN FRINGE OF THE LIGHT SNOW/PRECIPITATION SHIELD...THUS
VSBYS WILL REMAIN IN THE MVFR TO VFR CATEGORY...WHILE CIGS WILL BE
IN THE MVFR RANGE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...JJS
LONG TERM...AJ
AVIATION...KS
AREA FORECAST DISCUSSION
NWS MEDFORD OR
241 PM PST THU FEB 11 2016
.DISCUSSION...SKIES ARE THINNING OUT IN THE WAKE OF THE WEAK
SHORTWAVE THAT MOVED THROUGH THE AREA THIS MORNING. THIS IS IN
RESPONSE TO AN UPPER RIDGE BUILDING AHEAD OF A DEEPENING TROUGH NEAR
35N/140W. THIS SHOULD SLOW DOWN THE EASTWARD PROGRESSION OF THE
FRONT LATE TONIGHT. CURRENT HRRR MODEL SUGGEST THIS AND IS IN LINE
WITH THE NAM AND GFS. THEREFORE HAVE ADJUSTED POPS DOWN FOR THIS
EVENING AND TONIGHT, KEEPING THE BEST CHANCE FOR ANY RAIN OVER THE
MARINE WATERS AND ALONG THE COAST, NORTH OF CAPE BLANCO. I DON`T
THINK RAINFALL WILL MAKE MUCH IF ANY PROGRESS INLAND TONIGHT, BUT
STILL KEPT IN A SLIGHT CHANCE TO CHANCE ALONG THE SOUTH COAST AND IN
PORTIONS OF COOS AND NORTHWEST DOUGLAS COUNTY. SKIES SHOULD REMAIN
MOSTLY CLEAR THROUGH THIS EVENING BEFORE INCREASING AHEAD OF THE
COLD FRONT TONIGHT.
THE COLD FRONT WILL REACH THE COAST FRIDAY MORNING, THEN MOVING
ONSHORE DURING THE DAY FRIDAY. THIS WILL BRING THE BEST CHANCE FOR
MEASURABLE RAIN WITH MOST OF THE RAIN CENTERED ALONG THE COASTAL
MOUNTAINS AND CASCADES. EVEN THEN, QPF AMOUNTS ARE NOT EXPECTED TO
BE SIGNIFICANT AND MODELS HAVE BEEN TRENDING LOWER WITH QPF AMOUNTS.
SNOW LEVELS WILL LOWER ON FRIDAY, BUT WILL REMAIN ABOVE ALL THE
PASSES THROUGH FRIDAY.
A MOIST WESTERLY FLOW WILL SET UP FRIDAY NIGHT WITH A WEAK SHORT
WAVE MOVING THROUGH. MOST SHOWERS ARE EXPECTED TO REMAIN ALONG AND
WEST OF THE CASCADES, BUT THEY ARE EXPECTED TO BE LIGHT WITH SNOW
LEVELS BETWEEN 4500 AND 5000 FEET. THEREFORE WERE NOT EXPECTING
MUCH, IF ANY IMPACT ON ANY OF THE ROADS IN THE CASCADES.
500 MB HEIGHTS INCREASE SOME AS WEAK RIDGING BUILDS INTO THE AREA
SATURDAY. CONDITIONS SHOULD BE DRY DURING THE DAY, THEN A WARM FRONT
WILL ARRIVE SATURDAY NIGHT BRINGING STEADY LIGHT TO MODERATE
PRECIPITATION. THE BEST CHANCE FOR HEAVIER PRECIPITATION WILL BE IN
THE NORTHERN PART OF THE AREA SATURDAY EVENING, THEN THE FOCUS WILL
SHIFT SOUTH SATURDAY NIGHT THROUGH SUNDAY. SNOW LEVELS SATURDAY NIGHT
WILL INCREASE AND LIKELY BE ABOVE ALL THE PASSES THROUGH SUNDAY.
THE UPPER RIDGE WILL BUILD BACK INTO THE AREA SUNDAY NIGHT WITH
RAIN DECREASING, THEN ENDING FROM SOUTH TO NORTH. -PETRUCELLI
.LONG TERM DISCUSSION...MONDAY THROUGH THURSDAY. MODELS AND THE
ENSEMBLE PLOTS START IN REMARKABLY GOOD AGREEMENT MONDAY WITH AN
UPPER LEVEL RIDGE OVER THE WEST COAST SHUNTING SYSTEMS JUST TO THE
NORTH OF THE FORECAST AREA. IT IS NOT UNTIL WEDNESDAY MORNING THAT
THE MODEL PLOTS SHOW ANY SIGNIFICANT DIVERGENCE...BUT THE MAIN
DIFFERENCES ARE WITH TIMING OF THE SHIFTING OF THE UPPER LEVEL RIDGE
TO THE EAST. THE GFS IS SLIGHTLY FASTER ON WEDNESDAY BRINGING
PRECIPITATION ONTO THE COAST WEDNESDAY MORNING, WITH THE ECMWF
BRINGING IT IN IN THE AFTERNOON. FROM THERE THE OVERALL PATTERN OF
AN UPPER LEVEL TROUGH OVER THE WEST COAST REMAINS FOR ALL OF THE
PLOTS...BUT THAT IS THE ONLY AGREEMENT WITH PLOTS ALL OVER THE
PLACE WITH DEPTH AND PLACEMENT OF THESE UPPER TROUGHS. WITH THIS IN
MIND HAVE GONE WITH THE ENSEMBLE MEAN POPS FOR THE REMAINDER OF THE
EXTENDED FORECAST. -SVEN
&&
.AVIATION...FOR THE 12/00Z TAF CYCLE... VFR CONDITIONS WILL PREVAIL
INTO TONIGHT. AREAS OF MVFR CIGS/VSBYS IN LIGHT RAIN WILL DEVELOP
ALONG THE COAST LATE TONIGHT AND SPREAD INLAND TO THE CASCADES DURING
THE DAY FRIDAY WITH AREAS OF HIGHER TERRAIN BECOMING OBSCURED.
-JRS
&&
.MARINE...UPDATED 200 PM PST THU FEB 11 2016...MIXED WEST SWELL AT
19 TO 20 SECONDS AND SOUTHWEST SWELL AT 10 TO 11 SECONDS WILL BECOME
WESTERLY AT 17 TO 18 SECONDS TONIGHT...THEN REMAIN WESTERLY WITH A
GRADUALLY DIMINISHING PERIOD THROUGH SUNDAY. COMBINED SEAS WILL
BUILD TO 13 TO 14 FEET THROUGH FRIDAY MORNING...SUBSIDE TO 12 FEET
FRIDAY AFTERNOON THROUGH SATURDAY...REBUILD TO 12 TO 13 FEET
SATURDAY NIGHT...THEN SUBSIDE BELOW 10 FEET SUNDAY AFTERNOON. A WEAK
COLD FRONT WILL MOVE ONSHORE FRIDAY MORNING...AND THIS WILL BRING
SMALL CRAFT WINDS TO THE NORTHERN OUTER WATERS TONIGHT. OFFSHORE
HIGH PRESSURE WILL BUILD FRIDAY...THEN WEAKEN SATURDAY. A SLIGHTLY
STRONGER COLD FRONT WILL MOVE ONSHORE SATURDAY NIGHT. OFFSHORE HIGH
PRESSURE WILL REBUILD SUNDAY...THEN WEAKEN TUESDAY AS A STRONGER
FRONT APPROACHES THE AREA. -JRS
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST SUNDAY
FOR PZZ350-356-370-376.
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 4 AM PST FRIDAY
FOR PZZ370.
$$
AREA FORECAST DISCUSSION
NWS MEDFORD OR
902 AM PST THU FEB 11 2016
.DISCUSSION...THE WEAK SHORTWAVE THAT BROUGHT ISOLATED LIGHT
SHOWERS IS MOVING NORTHEAST AND SHOULD BE OUT OF THE FORECAST AREA
IN THE NEXT COUPLE OF HOURS TAKING ALL THE SHOWERS WITH IT. IN
IT`S WAKE SOME CLEARING IS DEVELOPING IN NORTHERN CAL AND
SOUTHWEST OREGON AND SOME OF THIS COULD MAKE IT INTO OUR AREA LATE
THIS MORNING INTO THIS AFTERNOON. THE LATEST HRRR MODEL SUGGEST
MOST HOURS AND LOCATIONS WILL BE DRY THIS AFTERNOON. THE GFS AND
NAM ALSO SHOW SIMILAR SOLUTIONS. THEREFORE, POPS WILL BE LOWERED
FOR THIS AFTERNOON.
DRY CONDITIONS ARE EXPECTED FOR MOST OF TONIGHT, THEN A COLD FRONT
WILL REACH THE COAST EARLY FRIDAY MORNING, THEN MOVE ONSHORE
DURING THE DAY FRIDAY. -PETRUCELLI
&&
.AVIATION...FOR THE 11/12Z TAF CYCLE...
VFR CONDITIONS ARE EXPECTED TO PREVAIL ACROSS THE VALLEYS AND
PRIMARY AIRFIELDS THROUGH THE TAF PERIOD. A WARM FRONT MOVING
THROUGH THIS MORNING INTO EARLY AFTERNOON WILL RESULT IN SOME LIGHT
SHOWER ACTIVITY. EXPECT SOME PARTIAL TERRAIN OBSCURATIONS THIS
MORNING INTO THE EARLY AFTERNOON MAINLY FROM THE CASCADES WESTWARD,
AND GREATEST OVER THE COAST RANGE. A BRIEF PERIOD OF MVFR IS
POSSIBLE ALONG THE COAST LATE THIS MORNING THROUGH EARLY AFTERNOON.
BTL
&&
.MARINE...UPDATED 305 AM PST THU FEB 11 2016...LONG PERIOD WEST
SWELL WILL BUILD TODAY THROUGH FRIDAY AND THEN PERSIST THROUGH
SATURDAY. A WARM FRONT WILL MOVE THROUGH TODAY FOLLOWED BY
INCREASING SOUTH WINDS AHEAD OF A COLD FRONT TONIGHT.
THIS COLD FRONT WILL MOVE THROUGH LATE TONIGHT THROUGH FRIDAY
MORNING. AFTER A BREAK ON FRIDAY AND MOST OF SATURDAY ANOTHER FRONT
WILL MOVE THROUGH SATURDAY NIGHT INTO SUNDAY. HIGH PRESSURE IS THEN
LIKELY TO REBUILD ALONG THE WEST COAST EARLY NEXT WEEK BEFORE A
STRONGER FRONT ARRIVES WEDNESDAY THROUGH THURSDAY. BTL
&&
.PREV DISCUSSION... /ISSUED 354 AM PST THU FEB 11 2016/
SHORT TERM...A SHORTWAVE RIDING UP THROUGH THE SOUTHWEST FLOW
ALOFT HAS KICKED OFF A FEW SHOWERS OVER OUR AREA THIS MORNING. NO
RAIN HAS HIT ANY OF THE OBSERVING SITES YET, BUT RADAR SHOWS
ISOLATED SHOWERS DRIFTING THROUGH RIGHT NOW. SHOWER COVERAGE WILL
INCREASE THIS MORNING AS THE MAIN PART OF THE SHORTWAVE ARRIVES,
AND RADAR IS SHOWING A LOT MORE SHOWERS OFF THE NW CALIFORNIA
COAST MOVING OUR WAY. MODELS SHOW THESE SHOWERS BEING CONFINED
MOSTLY TO THE CASCADE CREST AND WEST SIDE, BUT SOME SHOWERS
CERTAINLY COULD DRIFT OVER ONTO THE EAST SIDE. POPS HAVE BEEN
RAISED THIS MORNING.
WE WILL PROBABLY SEE AT LEAST SOME LINGERING SHOWERS THIS
AFTERNOON AND EVENING AS A WEAK COLD FRONT APPROACHES. THIS COLD
FRONT WILL MOVE ONSHORE TONIGHT AND FRIDAY MORNING AND BRING LIGHT
RAIN TO MOST WEST SIDE LOCATIONS AS IT MOVES INLAND FRIDAY. WE`RE
NOT EXPECTING A LOT OF RAIN WITH VALLEY LOCATIONS PROBABLY ONLY
SEEING A FEW HUNDREDTHS OF RAIN. HOWEVER, MOUNTAIN LOCATIONS COULD
SEE UP TO A QUARTER OF AN INCH OF RAIN. SNOW LEVELS WILL BE HIGH
(ABOVE 8000 FEET MOST OF THE DAY), SO IT WILL BE RAIN EXCEPT AT
THE HIGHEST PEAKS. SNOW MAY MAKE IT DOWN TO CRATER LAKE AND MT
ASHLAND BY DAY`S END, BUT MOST OF THE PRECIPITATION WILL HAVE
ALREADY FALLEN BY THEN. POPS WERE RAISED TO AT LEAST LIKELY ON THE
WEST SIDE FOR FRIDAY.
SATURDAY SHOULD BE A BIT OF A BREAK WITH LEFTOVER MORNING SHOWERS
OVER THE NORTH DECREASING THROUGH THE DAY. ELSEWHERE, THE DAY
OUGHT TO BE DRY. THE PREVIOUS SHIFT`S THINKING REGARDING SUNDAY`S
SYSTEM STILL LOOKS REASONABLE AND THE PREVIOUS LONG TERM
DISCUSSION FOLLOWS. THE ONE CHANGE MADE TO THE EXTENDED FORECAST
THIS MORNING WAS TO RAISE POPS ON SUNDAY. -WRIGHT
LONG TERM...SUNDAY THROUGH WEDNESDAY...A WARM FRONT WITH GOOD
ISENTROPIC ASCENT WILL RIDE OVER THE TOP OF A FLAT RIDGE ON
SUNDAY. THIS COMBINED WITH DEEP ONSHORE WEST-NORTHWEST FLOW WILL
RESULT IN RAIN, FOCUSED ON NORTH AND WEST FACING TERRAIN ALONG
AND WEST OF THE CASCADES WITH LIGHTER RAIN IN THE VALLEYS. RAIN
CHANCES DIMINISH SOUTH AND EAST OF THE MOUNTAINS. SNOW LEVELS WILL
BE WELL ABOVE THE MAJOR PASSES AND LIKELY ABOVE 8000 FEET IN MOST
AREAS. THE WARM FRONT WILL SHIFT NORTHWARD IN THE AFTERNOON AND
ISENTROPIC LIFT WILL EASE...EFFECTIVELY SHUTTING OFF RAINFALL
FROM SOUTH TO NORTH ACROSS THE CWA LATE SUNDAY AFTERNOON AND
NIGHT.
MODELS INDICATE THE RIDGE WILL STRENGTHEN A BIT OVER THE AREA
MONDAY WITH MOST, IF NOT ALL PRECIPITATION REMAINING TO THE
NORTH OF THE CWA. MODELS DIFFER A BIT WITH RESPECT TO ANOTHER
SHORTWAVE RIDING OVER THE RIDGE MONDAY NIGHT INTO TUESDAY. THE GFS
KEEPS IT WAY TO THE NORTH WHERE IT WOULD HAVE NO IMPACT ON OUR
WEATHER. THE ECMWF THOUGH HAS IT FARTHER SOUTH. DUE TO THE
UNCERTAINTY, WE HAVE INDICATED SLIGHT CHANCE TO CHANCE POPS FROM
THE COAST TO THE CASCADES AND NORTH OF THE UMPQUA DIVIDE. IT
SHOULD STAY DRY IN THE ROGUE VALLEY.
CONFIDENCE IS FAIRLY HIGH THAT THE NEXT SIGNIFICANT UPPER TROUGH
TO IMPACT THE AREA WILL ARRIVE TUESDAY NIGHT INTO WEDNESDAY. THE
SURFACE COLD FRONT WILL BE JUST OFFSHORE LATE TUESDAY NIGHT, THEN
MOVE ACROSS THE AREA WEDNESDAY INTO WEDNESDAY NIGHT. RAIN IS
LIKELY FROM THE COAST TO THE CASCADES WITH HIGH CHANCES EVEN OVER
THE EAST SIDE. SNOW LEVELS START OUT HIGH AHEAD OF THE FRONT, BUT
COULD DROP DOWN TO 3000 FEET BEHIND THE FRONT BY THURSDAY MORNING.
-SPILDE
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST SUNDAY
FOR PZZ350-356-370-376.
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 4 AM PST FRIDAY
FOR PZZ350-370.
$$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
434 PM EST THU FEB 11 2016
.SYNOPSIS...
A PERSISTENT NORTHWEST WIND WILL KEEP LAKE EFFECT AND UPSLOPE
SNOW SHOWERS GOING THE REST OF THIS AFTERNOON. AN ARCTIC BLAST
WILL DELIVER THE COLDEST AIR OF THE SEASON FOR VALENTINES WEEKEND.
THE ARCTIC FRONTAL BOUNDARY WILL BE ACCOMPANIED BY A ROUND OF
BLINDING SNOW SQUALLS LATE FRIDAY AND FRIDAY NIGHT...FOLLOWED BY
DANGEROUS COLD AND VERY LOW WIND CHILLS THAT ARE EXPECTED TO
IMPACT THE AREA SATURDAY INTO SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
NUMEROUS...NARROW BANDS OF SNOW SHOWERS AND BRIEF SQUALLS
CONTINUE TO STREAM SE AND WELL INLAND FROM THE GLAKES THIS
AFTERNOON...MAKING IT ALL THE WAY INTO PORTIONS OF THE LOWER SUSQ
VALLEY REGION /AND IN FACT...RIGHT TO THE MID ATLANTIC SEABOARD/.
BRIEF...REDUCED VSBYS TO BETWEEN 1/4-1/2SM WILL IMPACT TRAVEL
WITHIN THESE NARROW SNOW BANDS THAT COULD DROP UP TO ONE INCH OF
FLUFF IN JUST A 30 MINUTE PERIOD.
18Z HRRR COMBINED WITH A LOOK AT THE LOW-MID LEVEL LAPSE RATES
VIA THE NAM INDICATE THAT THE SNOW SHOWERS/BRIEF SQUALLS WILL
CONTINUE UNTIL 23 THU-01Z FRIDAY BEFORE QUICKLY DISSIPATING AS THE
SUBSIDENCE INVERSION DROPS FROM 7-8 KFT AGL...TO UNDER 4 KFT AGL.
WILL MAINTAIN CURRENT WINTER WEATHER ADVISORIES OVER THE LAURELS
AND WRN MTNS...AND LES WARNINGS AND ADVISORIES FOR THE FAR NW
SNOWBELT WHERE PERSISTENT UPSLOPE AND LES SNOWS ARE EXPECTED TO
CONTINUE INTO THIS EVENING.
THE WIND WILL MAKE IT FEEL MUCH COLDER LATE TDY WITH WIND CHILLS
BETWEEN -10 AND +10 ACROSS THE ENTIRE AREA. THE BLUSTERY
CONDITIONS WILL JUST BE A TASTE OF WHAT LOOKS LIKE IS ON THE
HORIZON FOR LATER FRIDAY NIGHT RIGHT INTO SUNDAY.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
SFC HIGH PRESSURE WILL SLIDE SOUTH OF THE STATE LATE TONIGHT
BRINGING GRADUAL CLEARING. FLURRIES AND SCATTERED SNOW SHOWERS
WILL LIFT NORTH EARLY TONIGHT AND BE CONFINED MAINLY TO THE
NORTHERN TIER BY AROUND MIDNIGHT.
TEMPS DROP INTO THE SINGLE DIGITS TONIGHT AS SOME CLEARING TAKES
PLACE IN THE NW...BUT THE CALM AIR IN THE SE COULD CAUSE THE TEMPS
THERE TO BECOME COLDER IN A FEW OF THE PERENNIAL COLD RURAL
AREAS...SUCH AS SEG AND THV - MAKING THEM 3-5F COLDER THAN THE
SURROUNDING LOCALES.
THE FIRST PART OF FRIDAY SHOULD BE QUIET WITH PARTLY TO MOSTLY
SUNNY SKIES AND RELATIVELY LIGHT WSW WIND. CLOUDS WILL QUICKLY
INCREASE FROM THE SW AS SOME MEAGER WARM ADVECTION KICKS IN AHEAD
OF THE WELL- ADVERTISED ARCTIC FRONT. SOME LIGHT SNOW/SNOW
SHOWERS WILL DEVELOP DURING THE AFTN...BUT ACCUMS SHOULD BE MEAGER
/GENERALLY UNDER 1/2 INCH. TEMPS WILL TRY TO GET INTO THE 20S ALL
OVER BUT THE PERSISTENT CLOUD COVER IN THE NW WILL LIKELY LIMIT
THEM TO THE UPPER TEENS.
ARCTIC FRONT AND AN EXPANSIVE AREA OF STEEP 850-700 MB LAPSE
RATES GREATER THAN 8C/KM WILL PLOW ACROSS THE STATE LATE
FRIDAY IN THE NW...AND AFTER DARK - FRIDAY NIGHT ELSEWHERE. THIS
SHOULD BE ONE OF THOSE ONCE IN A YEAR /OR SEVERAL YEAR/ EVENTS
COMPLETE WITH DANGEROUS BLINDING SNOW SQUALLS CREATING WIDESPREAD
TRAFFIC/TRAVEL PROBLEMS...FROM THE COMBINED EFFECT OF HEAVY
FALLING AND BLOWING SNOW - AMOUNTING TO BETWEEN 1-3 INCHES IN A
SHORT 30 TO 60 MINUTE PERIOD. THUNDER WAS ALSO MENTIONED IN THE
GRIDDED WEATHER FIELDS...ESP ACROSS THE NW HALF OF THE STATE BASED
ON THE LATE DAY/EVENING TIMING OF THE ARCTIC FROPA.
WIND CHILLS DIP TO UNDER ADVISORY CRITERIA /-15F/ EARLY SAT
MORNING ACROSS THE NRN MTNS...AND DROP TO NEAR OR SEVERAL DEG F
BELOW ZERO ELSEWHERE BY THEN.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
*IMPACT WEATHER HIGHLIGHTS: FRIGID TEMPERATURES AND DANGEROUS WIND
CHILLS FOR VALENTINES WEEKEND. POTENTIAL WINTER STORM EARLY NEXT
WEEK.
POLAR VORTEX DIVING INTO NORTHERN NEW ENGLAND WILL DELIVER THE
COLDEST AIR OF THE SEASON WITH ARCTIC BLAST INTO CENTRAL PA SAT-
SUN. THE GLOBAL MODELS AND ENSEMBLES KEEP A MEAN TROUGH IN PLACE
OVER THE EASTERN US INTO THE MIDDLE OF NEXT WEEK. THE MOST NOTABLE
FEATURE DURING THE PERIOD WILL BE A LOW PRESSURE SYSTEM TRACKING
UP THE EAST COAST ON TUESDAY. THE LATEST 11/12Z MODEL GUIDANCE
HAS TRENDED WEST WITH THE LOW TRACK...BUT THERE IS STILL A DECENT
SPREAD. AT THIS TIME PRECIPITATION WITH THIS SYSTEM APPEARS LIKELY
MON-TUE BUT THE TRACK WILL ULTIMATELY DETERMINE PRECIPITATION
TYPE. NEXT WEEK SHOULD END ON A MILDER NOTE.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
LIKELY WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM 0F IN THE LOWER SUSQ. VALLEY
TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA. A WIND
CHILL WATCH WAS ISSUED FOR NORTHERN PA WHERE CONFIDENCE IS HIGH IN
REACHING -25F WIND CHILLS. WIND CHILL HEADLINES ARE A GOOD BET
IN LATER SHIFTS FOR THE REMAINDER OF THE AREA AND PRECAUTIONS
SHOULD BE MADE NOW TO PROTECT/PREPARE FOR THE UPCOMING COLD SNAP.
A MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT WEEK.
THE MODEL SPREAD HAS NARROWED A BIT CONCERNING A POTENTIAL WINTER
STORM SYSTEM IMPACTING THE MID ATLC/NORTHEAST NEXT MON-TUE. THE
11/12Z OPERATIONAL EC REMAINS ON THE WWD EDGE OF THE ENVELOPE
FOLLOWED BY THE CANADIAN GEM AND GFS/GEFS. THE GFS/GEFS HAVE BOTH
TRENDED WWD FROM THE PREVIOUS RUN. CONFIDENCE REMAINS LOW ON
PTYPES BUT ALL THE MODELS ARE SIGNALING A SIGNIFICANT QPF
EVENT...AND THEREFORE HAVE INCREASED POPS IN THE THE LKLY RANGE
FOR DAY 5.5-6 /MON NGT-TUESDAY/.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
LAKE ENHANCED OROGRAPHIC SNOW WILL RESULT IN MAINLY IFR VSBYS AT
KBFD/KJST AND POSSIBLY MVFR AT AOO...THROUGH THE FIRST HALF OF THE
EVENING. THESE CONDITIONS WILL GRADUALLY IMPROVE WHEN THE MEAN
LLVL WIND BACKS FROM THE NW...TO A MORE WESTERLY DIRECTION AS HIGH
PRESSURE SLIDES BY JUST TO OUR SOUTH ACROSS THE MIDDLE OHIO RIVER
VALLEY...BY 06Z.
THROUGHOUT THE CENTRAL RIDGE...THE VALLEY REGION...AND OVER THE
SUSQ VALLEY AIRFIELDS...EXPECT MAINLY VFR CONDITIONS. THE SNOW
BANDS COULD POSSIBLY BRING IPT AT UNV TO MFR CIGS THROUGH 03Z...WITH
EVEN SOME VERY BRIEF IFR IN THE HEAVIER SNOW SHOWERS AND SQUALLS.
A TIGHT PRES GRADIENT WILL BRING GUSTY WINDS UP TO 35KTS FOR THE
REST OF THIS AFTERNOON AND EARLY EVENING AS DIURNAL
HEATING/MIXING WITHIN THE RATHER DEEP BOUNDARY LAYER ALLOWS
STRONGER WINDS ALOFT TO MIX TO GROUND LEVEL.
ARRIVAL OF SFC RIDGE SHOULD BRING WIDESPREAD VFR CONDS AND
DIMINISHING WIND TO CENTRAL PA THIS EVENING...AND CONTINUING
THROUGH AT LEAST THE FIRST HALF OF FRIDAY.
OUTLOOK...
FRI...PM SHSN/VIS REDUCTIONS LIKELY...ESP W MTNS. PERIODS OF
LIFR/VLIFR IN INTENSE SNOW SQUALLS LATE FRIDAY /NW/ AND FRIDAY
NIGHT EARLY SAT MORNING CENTRAL AND SE.
SAT...WINDY. SHSN/REDUCED VIS POSS W MTNS...MAINLY AM.
SUN...NO SIG WX EXPECTED.
MON...PM SNOW POSSIBLE.
MON NIGHT AND TUE...SNOW LIKELY NW HALF OF PENN...WITH RAIN OR
SNOW IN THE SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ005.
WIND CHILL WATCH FROM LATE FRIDAY NIGHT THROUGH SUNDAY MORNING
FOR PAZ004>006-037-041-042.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THIS EVENING FOR
PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ010-017-024-033.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
422 PM EST THU FEB 11 2016
.SYNOPSIS...
A PERSISTENT NORTHWEST WIND WILL KEEP LAKE EFFECT AND UPSLOPE
SNOW SHOWERS GOING THE REST OF THIS AFTERNOON. AN ARCTIC BLAST
WILL DELIVER THE COLDEST AIR OF THE SEASON FOR VALENTINES WEEKEND.
THE ARCTIC FRONTAL BOUNDARY WILL BE ACCOMPANIED BY A ROUND OF
BLINDING SNOW SQUALLS LATE FRIDAY AND FRIDAY NIGHT...FOLLOWED BY
DANGEROUS COLD AND VERY LOW WIND CHILLS THAT ARE EXPECTED TO
IMPACT THE AREA SATURDAY INTO SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
NUMEROUS...NARROW BANDS OF SNOW SHOWERS AND BRIEF SQUALLS
CONTINUE TO STREAM SE AND WELL INLAND FROM THE GLAKES THIS
AFTERNOON...MAKING IT ALL THE WAY INTO PORTIONS OF THE LOWER SUSQ
VALLEY REGION /AND IN FACT...RIGHT TO THE MID ATLANTIC SEABOARD/.
BRIEF...REDUCED VSBYS TO BETWEEN 1/4-1/2SM WILL IMPACT TRAVEL
WITHIN THESE NARROW SNOW BANDS THAT COULD DROP UP TO ONE INCH OF
FLUFF IN JUST A 30 MINUTE PERIOD.
18Z HRRR COMBINED WITH A LOOK AT THE LOW-MID LEVEL LAPSE RATES
VIA THE NAM INDICATE THAT THE SNOW SHOWERS/BRIEF SQUALLS WILL
CONTINUE UNTIL 23 THU-01Z FRIDAY BEFORE QUICKLY DISSIPATING AS THE
SUBSIDENCE INVERSION DROPS FROM 7-8 KFT AGL...TO UNDER 4 KFT AGL.
WILL MAINTAIN CURRENT WINTER WEATHER ADVISORIES OVER THE LAURELS
AND WRN MTNS...AND LES WARNINGS AND ADVISORIES FOR THE FAR NW
SNOWBELT WHERE PERSISTENT UPSLOPE AND LES SNOWS ARE EXPECTED TO
CONTINUE INTO THIS EVENING.
THE WIND WILL MAKE IT FEEL MUCH COLDER LATE TDY WITH WIND CHILLS
BETWEEN -10 AND +10 ACROSS THE ENTIRE AREA. THE BLUSTERY
CONDITIONS WILL JUST BE A TASTE OF WHAT LOOKS LIKE IS ON THE
HORIZON FOR LATER FRIDAY NIGHT RIGHT INTO SUNDAY.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
SFC HIGH PRESSURE WILL SLIDE SOUTH OF THE STATE LATE TONIGHT
BRINGING GRADUAL CLEARING. FLURRIES AND SCATTERED SNOW SHOWERS
WILL LIFT NORTH EARLY TONIGHT AND BE CONFINED MAINLY TO THE
NORTHERN TIER BY AROUND MIDNIGHT.
TEMPS DROP INTO THE SINGLE DIGITS TONIGHT AS SOME CLEARING TAKES
PLACE IN THE NW...BUT THE CALM AIR IN THE SE COULD CAUSE THE TEMPS
THERE TO BECOME COLDER IN A FEW OF THE PERENNIAL COLD RURAL
AREAS...SUCH AS SEG AND THV - MAKING THEM 3-5F COLDER THAN THE
SURROUNDING LOCALES.
THE FIRST PART OF FRIDAY SHOULD BE QUIET WITH PARTLY TO MOSTLY
SUNNY SKIES AND RELATIVELY LIGHT WSW WIND. CLOUDS WILL QUICKLY
INCREASE FROM THE SW AS SOME MEAGER WARM ADVECTION KICKS IN AHEAD
OF THE WELL- ADVERTISED ARCTIC FRONT. SOME LIGHT SNOW/SNOW
SHOWERS WILL DEVELOP DURING THE AFTN...BUT ACCUMS SHOULD BE MEAGER
/GENERALLY UNDER 1/2 INCH. TEMPS WILL TRY TO GET INTO THE 20S ALL
OVER BUT THE PERSISTENT CLOUD COVER IN THE NW WILL LIKELY LIMIT
THEM TO THE UPPER TEENS.
ARCTIC FRONT AND AN EXPANSIVE AREA OF STEEP 850-700 MB LAPSE
RATES GREATER THAN 8C/KM WILL PLOW ACROSS THE STATE LATE
FRIDAY IN THE NW...AND AFTER DARK - FRIDAY NIGHT ELSEWHERE. THIS
SHOULD BE ONE OF THOSE ONCE IN A YEAR /OR SEVERAL YEAR/ EVENTS
COMPLETE WITH DANGEROUS BLINDING SNOW SQUALLS CREATING WIDESPREAD
TRAFFIC/TRAVEL PROBLEMS...FROM THE COMBINED EFFECT OF HEAVY
FALLING AND BLOWING SNOW - AMOUNTING TO BETWEEN 1-3 INCHES IN A
SHORT 30 TO 60 MINUTE PERIOD. THUNDER WAS ALSO MENTIONED IN THE
GRIDDED WEATHER FIELDS...ESP ACROSS THE NW HALF OF THE STATE BASED
ON THE LATE DAY/EVENING TIMING OF THE ARCTIC FROPA.
WIND CHILLS DIP TO UNDER ADVISORY CRITERIA /-15F/ EARLY SAT
MORNING ACROSS THE NRN MTNS...AND DROP TO NEAR OR SEVERAL DEG F
BELOW ZERO ELSEWHERE BY THEN.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
*IMPACT WEATHER HIGHLIGHTS: FRIGID TEMPERATURES AND DANGEROUS WIND
CHILLS FOR VALENTINES WEEKEND. POTENTIAL WINTER STORM EARLY NEXT
WEEK.
POLAR VORTEX DIVING INTO NORTHERN NEW ENGLAND WILL DELIVER THE
COLDEST AIR OF THE SEASON WITH ARCTIC BLAST INTO CENTRAL PA SAT-
SUN. THE GLOBAL MODELS AND ENSEMBLES KEEP A MEAN TROUGH IN PLACE
OVER THE EASTERN US INTO THE MIDDLE OF NEXT WEEK. THE MOST NOTABLE
FEATURE DURING THE PERIOD WILL BE A LOW PRESSURE SYSTEM TRACKING
UP THE EAST COAST ON TUESDAY. THE LATEST 11/12Z MODEL GUIDANCE
HAS TRENDED WEST WITH THE LOW TRACK...BUT THERE IS STILL A DECENT
SPREAD. AT THIS TIME PRECIPITATION WITH THIS SYSTEM APPEARS LIKELY
MON-TUE BUT THE TRACK WILL ULTIMATELY DETERMINE PRECIPITATION
TYPE. NEXT WEEK SHOULD END ON A MILDER NOTE.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
LIKELY WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM 0F IN THE LOWER SUSQ. VALLEY
TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA. A WIND
CHILL WATCH WAS ISSUED FOR NORTHERN PA WHERE CONFIDENCE IS HIGH IN
REACHING -25F WIND CHILLS. WIND CHILL HEADLINES ARE A GOOD BET
IN LATER SHIFTS FOR THE REMAINDER OF THE AREA AND PRECAUTIONS
SHOULD BE MADE NOW TO PROTECT/PREPARE FOR THE UPCOMING COLD SNAP.
A MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT WEEK.
THE MODEL SPREAD HAS NARROWED A BIT CONCERNING A POTENTIAL WINTER
STORM SYSTEM IMPACTING THE MID ATLC/NORTHEAST NEXT MON-TUE. THE
11/12Z OPERATIONAL EC REMAINS ON THE WWD EDGE OF THE ENVELOPE
FOLLOWED BY THE CANADIAN GEM AND GFS/GEFS. THE GFS/GEFS HAVE BOTH
TRENDED WWD FROM THE PREVIOUS RUN. CONFIDENCE REMAINS LOW ON
PTYPES BUT ALL THE MODELS ARE SIGNALING A SIGNIFICANT QPF
EVENT...AND THEREFORE HAVE INCREASED POPS IN THE THE LKLY RANGE
FOR DAY 5.5-6 /MON NGT-TUESDAY/.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
LAKE ENHANCED OROGRAPHIC SNOW WILL RESULT IN MAINLY IFR VSBYS AT
KBFD/KJST THROUGH THIS AFTERNOON. THESE CONDITIONS WILL GRADUALLY
IMPROVE BEGINNING THIS EVENING WHEN THE MEAN LLVL WIND BACKS FROM
THE NW...TO A MORE WESTERLY DIRECTION AS HIGH PRESSURE SLIDES BY
JUST TO OUR SOUTH ACROSS THE MIDDLE OHIO RIVER VALLEY.
THROUGHOUT THE CENTRAL RIDGE AND VALLEY REGION AND OVER THE SUSQ
VALLEY AIRFIELDS...MAINLY VFR AT 19Z...MAY DROP BRIEFLY TO UPPER
MVFR CIGS AND VSBYS...WITH EVEN SOME VERY BRIEF IFR IN THE
HEAVIER SNOW SHOWERS AND SQUALLS.
A TIGHT PRES GRADIENT WILL BRING GUSTY WINDS UP TO 25KTS FOR THE
REST OF THIS AFTERNOON AS DIURNAL HEATING/MIXING WITHIN THE RATHER
DEEP BOUNDARY LAYER ALLOWS STRONGER WINDS ALOFT TO MIX TO GROUND
LEVEL.
ARRIVAL OF SFC RIDGE SHOULD BRING WIDESPREAD VFR CONDS AND
DIMINISHING WIND TO CENTRAL PA THIS EVENING...AND CONTINUING
THROUGH AT LEAST THE FIRST HALF OF FRIDAY.
OUTLOOK...
FRI...PM SHSN/VIS REDUCTIONS LIKELY...ESP W MTNS. PERIODS OF
LIFR/VLIFR IN INTENSE SNOW SQUALLS LATE FRIDAY /NW/ AND FRIDAY
NIGHT EARLY SAT MORNING CENTRAL AND SE.
SAT...WINDY. SHSN/REDUCED VIS POSS W MTNS...MAINLY AM.
SUN...NO SIG WX EXPECTED.
MON...PM SNOW POSSIBLE.
MON NIGHT AND TUE...SNOW LIKELY NW HALF OF PENN...WITH RAIN OR
SNOW IN THE SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ005.
WIND CHILL WATCH FROM LATE FRIDAY NIGHT THROUGH SUNDAY MORNING
FOR PAZ004>006-037-041-042.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THIS EVENING FOR
PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ010-017-024-033.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
305 PM EST THU FEB 11 2016
.SYNOPSIS...
A PERSISTENT NORTHWEST WIND WILL KEEP LAKE EFFECT AND UPSLOPE
SNOW SHOWERS GOING THE REST OF THIS AFTERNOON. AN ARCTIC BLAST
WILL DELIVER THE COLDEST AIR OF THE SEASON FOR VALENTINES WEEKEND.
THE ARCTIC FRONTAL BOUNDARY WILL BE ACCOMPANIED BY A ROUND OF
BLINDING SNOW SQUALLS LATE FRIDAY AND FRIDAY NIGHT... FOLLOWED BY
DANGEROUS COLD AND VERY LOW WIND CHILLS THAT ARE EXPECTED TO
IMPACT THE AREA SATURDAY INTO SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
NUMEROUS...NARROW BANDS OF SNOW SHOWERS AND BRIEF SQUALLS
CONTINUE TO STREAM SE AND WELL INLAND FROM THE GLAKES THIS
AFTERNOON...MAKING IT ALL THE WAY INTO PORTIONS OF THE LOWER SUSQ
VALLEY REGION /AND IN FACT...RIGHT TO THE MID ATLANTIC SEABOARD/.
BRIEF...REDUCED VSBYS TO BETWEEN 1/4-1/2SM WILL IMPACT TRAVEL
WITHIN THESE NARROW SNOW BANDS THAT COULD DROP UP TO ONE INCH OF
FLUFF IN JUST A 30 MINUTE PERIOD.
18Z HRRR COMBINED WITH A LOOK AT THE LOW-MID LEVEL LAPSE RATES
VIA THE NAM INDICATE THAT THE SNOW SHOWERS/BRIEF SQUALLS WILL
CONTINUE UNTIL 23 THU-01Z FRIDAY BEFORE QUICKLY DISSIPATING AS THE
SUBSIDENCE INVERSION DROPS FROM 7-8 KFT AGL...TO UNDER 4 KFT AGL.
WILL MAINTAIN CURRENT WINTER WEATHER ADVISORIES OVER THE LAURELS
AND WRN MTNS...AND LES WARNINGS AND ADVISORIES FOR THE FAR NW
SNOWBELT WHERE PERSISTENT UPSLOPE AND LES SNOWS ARE EXPECTED TO
CONTINUE INTO THIS EVENING.
THE WIND WILL MAKE IT FEEL MUCH COLDER LATE TDY WITH WIND CHILLS
BETWEEN -10 AND +10 ACROSS THE ENTIRE AREA. THE BLUSTERY
CONDITIONS WILL JUST BE A TASTE OF WHAT LOOKS LIKE IS ON THE
HORIZON FOR LATER FRIDAY NIGHT RIGHT INTO SUNDAY.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
SFC HIGH PRESSURE WILL SLIDE SOUTH OF THE STATE LATE TONIGHT
BRINGING GRADUAL CLEARING. FLURRIES AND SCATTERED SNOW SHOWERS
WILL LIFT NORTH EARLY TONIGHT AND BE CONFINED MAINLY TO THE
NORTHERN TIER BY AROUND MIDNIGHT.
TEMPS DROP INTO THE SINGLE DIGITS TONIGHT AS SOME CLEARING TAKES
PLACE IN THE NW...BUT THE CALM AIR IN THE SE COULD CAUSE THE TEMPS
THERE TO BECOME COLDER IN A FEW OF THE PERENNIAL COLD RURAL
AREAS...SUCH AS SEG AND THV - MAKING THEM 3-5F COLDER THAN THE
SURROUNDING LOCALES.
THE FIRST PART OF FRIDAY SHOULD BE QUIET WITH PARTLY TO MOSTLY
SUNNY SKIES AND RELATIVELY LIGHT WSW WIND. CLOUDS WILL QUICKLY
INCREASE FROM THE SW AS SOME MEAGER WARM ADVECTION KICKS IN AHEAD
OF THE WELL- ADVERTISED ARCTIC FRONT. SOME LIGHT SNOW/SNOW
SHOWERS WILL DEVELOP DURING THE AFTN...BUT ACCUMS SHOULD BE MEAGER
/GENERALLY UNDER 1/2 INCH. TEMPS WILL TRY TO GET INTO THE 20S ALL
OVER BUT THE PERSISTENT CLOUD COVER IN THE NW WILL LIKELY LIMIT
THEM TO THE UPPER TEENS.
ARCTIC FRONT AND AN EXPANSIVE AREA OF STEEP 850-700 MB LAPSE
RATES GREATER THAN 8C/KM WILL PLOW ACROSS THE STATE LATE
FRIDAY IN THE NW...AND AFTER DARK - FRIDAY NIGHT ELSEWHERE. THIS
SHOULD BE ONE OF THOSE ONCE IN A YEAR /OR SEVERAL YEAR/ EVENTS
COMPLETE WITH DANGEROUS BLINDING SNOW SQUALLS CREATING WIDESPREAD
TRAFFIC/TRAVEL PROBLEMS...FROM THE COMBINED EFFECT OF HEAVY
FALLING AND BLOWING SNOW - AMOUNTING TO BETWEEN 1-3 INCHES IN A
SHORT 30 TO 60 MINUTE PERIOD. THUNDER WAS ALSO MENTIONED IN THE
GRIDDED WEATHER FIELDS...ESP ACROSS THE NW HALF OF THE STATE BASED
ON THE LATE DAY/EVENING TIMING OF THE ARCTIC FROPA.
WIND CHILLS DIP TO UNDER ADVISORY CRITERIA /-15F/ EARLY SAT
MORNING ACROSS THE NRN MTNS...AND DROP TO NEAR OR SEVERAL DEG F
BELOW ZERO ELSEWHERE BY THEN.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS LIKELY WITH ARCTIC FRONT
FRIDAY NIGHT-SATURDAY. FRIGID TEMPERATURES AND DANGEROUS WIND
CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
EASTERN US INTO NEXT WEEK. EMERGENCE OF SOUTHERN STREAM SHORTWAVE
AND ITS INTERACTION WITH THE NORTHERN STREAM FLOW CREATES THE
POTENTIAL FOR WINTER PRECIPITATION MON-WED BUT WITH A HIGH DEGREE
OF UNCERTAINTY/LOW CONFIDENCE. A PATTERN SHIFT TO PACIFIC ZONAL-TO
SOUTHWEST FLOW ALOFT WITH RISING/ABOVE NORMAL HEIGHTS IS FCST BY
THE END OF NEXT WEEK. THIS FAVORS A RETURN TO MILDER WEATHER.
LAKE EFFECT AND UPSLOPE SNOW SHOWERS CONTINUE INTO THE WEEKEND
BEFORE TAPERING OFF ON SUNDAY...AS ARCTIC HIGH BUILDS OVER THE
REGION. ADDITIONAL LIGHT SNOW ACCUMULATIONS ARE LIKELY IN THE
FAVORED NORTHWEST SNOWBELT AND HIGHER TERRAIN ALONG THE
ALLEGHENIES/LAUREL HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
LIKELY WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM 0F IN THE LOWER SUSQ. VALLEY
TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA. WIND
CHILL HEADLINES ARE A GOOD BET AND PRECAUTIONS SHOULD BE MADE NOW
TO PROTECT/PREPARE FOR THE UPCOMING COLD SNAP.
A MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT WEEK.
THERE IS STILL A LOT OF SPREAD CONCERNING A POTENTIAL STORM SYSTEM
IMPACTING THE NORTHEAST EARLY NEXT WEEK. THE OPERATIONAL EC
REMAINS MORE BULLISH THAN THE GFS IN DEVELOPING A SIGNIFICANT
CYCLONE AND HAS TRENDED EVEN FURTHER TO THE WEST WITH IS 10/12Z
RUN. CONFIDENCE REMAINS LOW BUT THE SYSTEM WILL NEED TO BE MONITORED.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
LAKE ENHANCED OROGRAPHIC SNOW WILL RESULT IN MAINLY IFR VSBYS AT
KBFD/KJST THROUGH THIS AFTERNOON. THESE CONDITIONS WILL GRADUALLY
IMPROVE BEGINNING THIS EVENING WHEN THE MEAN LLVL WIND BACKS FROM
THE NW...TO A MORE WESTERLY DIRECTION AS HIGH PRESSURE SLIDES BY
JUST TO OUR SOUTH ACROSS THE MIDDLE OHIO RIVER VALLEY.
THROUGHOUT THE CENTRAL RIDGE AND VALLEY REGION AND OVER THE SUSQ
VALLEY AIRFIELDS...MAINLY VFR AT 19Z...MAY DROP BRIEFLY TO UPPER
MVFR CIGS AND VSBYS...WITH EVEN SOME VERY BRIEF IFR IN THE
HEAVIER SNOW SHOWERS AND SQUALLS.
A TIGHT PRES GRADIENT WILL BRING GUSTY WINDS UP TO 25KTS FOR THE
REST OF THIS AFTERNOON AS DIURNAL HEATING/MIXING WITHIN THE RATHER
DEEP BOUNDARY LAYER ALLOWS STRONGER WINDS ALOFT TO MIX TO GROUND
LEVEL.
ARRIVAL OF SFC RIDGE SHOULD BRING WIDESPREAD VFR CONDS AND
DIMINISHING WIND TO CENTRAL PA THIS EVENING...AND CONTINUING
THROUGH AT LEAST THE FIRST HALF OF FRIDAY.
OUTLOOK...
FRI...PM SHSN/VIS REDUCTIONS LIKELY...ESP W MTNS. PERIODS OF
LIFR/VLIFR IN INTENSE SNOW SQUALLS LATE FRIDAY /NW/ AND FRIDAY
NIGHT EARLY SAT MORNING CENTRAL AND SE.
SAT...WINDY. SHSN/REDUCED VIS POSS W MTNS...MAINLY AM.
SUN...NO SIG WX EXPECTED.
MON...PM SNOW POSSIBLE.
MON NIGHT AND TUE...SNOW LIKELY NW HALF OF PENN...WITH RAIN OR
SNOW IN THE SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THIS EVENING FOR
PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ010-017-024-033.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1206 PM EST THU FEB 11 2016
.SYNOPSIS...
A PERSISTENT NORTHWEST WIND WILL KEEP LAKE EFFECT AND UPSLOPE
SNOW SHOWERS GOING THROUGH THIS AFTERNOON. AN ARCTIC BLAST WILL
DELIVER THE COLDEST AIR OF THE SEASON FOR VALENTINES
WEEKEND...PRECEDED BY A ROUND OF BLINDING SNOW SQUALLS LATE
FRIDAY AND FRIDAY NIGHT...AND FOLLOWED BY DANGEROUS COLD AND VERY
LOW WIND CHILLS THAT ARE EXPECTED TO IMPACT THE AREA SATURDAY INTO
SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MULTIPLE NARROW BANDS OF SNOW SQUALLS CONTINUE TO STREAM SE AND
WELL INLAND FROM THE GLAKES LATE THIS MORNING...MAKING IT ALL THE
WAY INTO PORTIONS OF THE LOWER SUSQ VALLEY REGION /AND IN
FACT...RIGHT TO THE MID ATLANTIC SEABOARD/. BRIEF...GREATLY
REDUCED VSBYS POSE A SIGNIF IMPACT TO TRAVEL WITHIN THESE NARROW
BUT RATHER INTENSE SNOW BANDS THAT COULD DROP UP TO ONE INCH OF
FLUFF IN JUST A 15-20 MINUTE PERIOD.
LATEST...15Z HRRR COMBINED WITH A LOOK AT THE LOW-MID LEVEL LAPSE
RATES VIA THE NAM INDICATE THAT THE TARGET AREA FOR ONE OR TWO
EXTENSIVE/INTENSE SQUALL BANDS SHOULD SHIFT TO THE NE HALF OF THE
CWA THIS AFTERNOON AS MEAN BLYR WINDS BACK JUST 5-10 DEGREES.
THESE SNOW BANDS WILL CONTINUE TO HAVE A GOOD DUAL LAKE CONNECTION
FLOWING OVER THE LONG AXIS OF LAKE HURON. WILL FORECAST MAINLY A
COATING TO ONE INCH ALONG AND NORTH OF A LINE FROM KUNV TO
KSEG...HOWEVER SOME LOCATIONS IN THE CENTRAL MTNS AND WEST
BRANCH/MIDDLE SUSQ VALLEY COULD SEE ANOTHER QUICK 2-3 INCHES OF
FLUFFY/WIND BLOWN SNOW BETWEEN 14Z AND 23Z.
SOME LOCATIONS MAY NEED TO BE PLACED IN A SHORT FUSED WINT
WEATHER ADVIS DEPENDING ON EXACTLY WHERE THIS MESOSCALE FEATURE
SETS UP. WILL BE MONITORING RADAR TRENDS AND HIGH RES MESO MODELS
CLOSELY THIS AFTERNOON.
WILL MAINTAIN CURRENT WINTER WEATHER ADVISORIES OVER THE LAURELS
AND WRN MTNS...AND LES WARNINGS AND ADVISORIES FOR THE FAR NW
SNOWBELT WHERE PERSISTENT UPSLOPE AND LES SNOWS ARE EXPECTED TO
CONTINUE INTO THIS EVENING BEFORE THE MEAN LLVL FLOW BACKS MORE TO
THE WEST AND THE SUBSIDENCE INVERSION BEGINS TO DROP QUICKLY FROM
7-8 KFT AGL...TO UNDER 4 KFT AGL.
THE WIND WILL MAKE IT FEEL MUCH COLDER TODAY WITH WIND CHILLS
BETWEEN -10 AND +10 ACROSS THE ENTIRE AREA ALL DAY LONG. THE
BLUSTERY CONDITIONS WILL JUST BE A TASTE OF WHAT LOOKS LIKE IS ON
THE HORIZON FOR SATURDAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
THE SNOW SHOWERS DO BEGIN TO TAPER OFF IN THE LATE AFTN AND
EVENING. THE ACCUMS SHOULD BECOME NEGLIGABLE NOT TOO LONG AFTER
SUNSET. THE END TIMING OF THE ADVYS/WARNING WILL BE KEPT AS IS AT
03Z. HOWEVER...MANY PLACES S OF ELK CO WILL SEE JUST A FLURRY OR
TWO IN THE EVENING. TEMPS DROP INTO THE SINGLE DIGITS TONIGHT AS
SOME CLEARING TAKES PLACE IN THE NW...BUT THE CALM AIR IN THE SE
COULD CAUSE THE TEMPS THERE TO BECOME COLDER. SNOW PACK AND CALM
AIR DO WONDERS TO MAKE IT COLDER THAN WE THINK IT WILL BE. WILL
PAINT IN A DIP AROUND THE TYPICAL FRIDGES OF SEG AND THV - MAKING
THEM 3-5F COLDER THAN THE SURROUNDING LOCALES.
THE FIRST PART OF FRIDAY SHOULD BE QUIET SAVE A QUICK INCREASE IN
CLOUDS FROM THE SW AS SOME MEAGER WARM ADVECTION KICKS IN AHEAD OF
THE WELL-ADVERTISED ARCTIC FRONT. SOME LIGHT SNOW WILL PROBABLY
BREAK OUT/SLIDE IN DURING THE AFTN. TEMPS WILL TRY TO GET INTO THE
20S ALL OVER BUT THE PERSISTENT CLOUD COVER IN THE NW WILL LIKELY
KEEP THEM U20.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS LIKELY WITH ARCTIC FRONT
FRIDAY NIGHT-SATURDAY. FRIGID TEMPERATURES AND DANGEROUS WIND
CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
EASTERN US INTO NEXT WEEK. EMERGENCE OF SOUTHERN STREAM SHORTWAVE
AND ITS INTERACTION WITH THE NORTHERN STREAM FLOW CREATES THE
POTENTIAL FOR WINTER PRECIPITATION MON-WED BUT WITH A HIGH DEGREE
OF UNCERTAINTY/LOW CONFIDENCE. A PATTERN SHIFT TO PACIFIC ZONAL-TO
SOUTHWEST FLOW ALOFT WITH RISING/ABOVE NORMAL HEIGHTS IS FCST BY
THE END OF NEXT WEEK. THIS FAVORS A RETURN TO MILDER WEATHER.
LAKE EFFECT AND UPSLOPE SNOW SHOWERS CONTINUE INTO THE WEEKEND
BEFORE TAPERING OFF ON SUNDAY...AS ARCTIC HIGH BUILDS OVER THE
REGION. ADDITIONAL LIGHT SNOW ACCUMULATIONS ARE LIKELY IN THE
FAVORED NORTHWEST SNOWBELT AND HIGHER TERRAIN ALONG THE
ALLEGHENIES/LAUREL HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
LIKELY WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM 0F IN THE LOWER SUSQ. VALLEY
TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA. WIND
CHILL HEADLINES ARE A GOOD BET AND PRECAUTIONS SHOULD BE MADE NOW
TO PROTECT/PREPARE FOR THE UPCOMING COLD SNAP.
A MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT WEEK.
THERE IS STILL A LOT OF SPREAD CONCERNING A POTENTIAL STORM SYSTEM
IMPACTING THE NORTHEAST EARLY NEXT WEEK. THE OPERATIONAL EC
REMAINS MORE BULLISH THAN THE GFS IN DEVELOPING A SIGNIFICANT
CYCLONE AND HAS TRENDED EVEN FURTHER TO THE WEST WITH IS 10/12Z
RUN. CONFIDENCE REMAINS LOW BUT THE SYSTEM WILL NEED TO BE MONITORED.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
LAKE ENHANCED OROGRAPHIC SNOW WILL RESULT IN MAINLY IFR VSBYS AT
KBFD/KJST THROUGH THIS AFTERNOON. THESE OCNDITIONS WILL GRADUALLY
IMPROVE BEGINNING THIS EVENING WHEN THE MEAN LLVL WINDS BACKS FROM
THE NW...TO A MORE WESTERLY DIRECTION AS HIGH PRESSURE SLIDES BY
JUST TO OUR SOUTH ACROSS THE MIDDLE OHIO RIVER VALLEY.
THROUGHOUT THE CENTRAL RIDGE AND VALLEY REGION AND OVER THE SUSQ
VALLEY AIRFIELDS...MAINLY VFR AT 17Z...WILL LIKELY DROP TO
FREQUENT MVFR CIGS AND VSBYS...WITH EVEN SOME VERY BRIEF IFR IN
THE HEAVIER SNOW SHOWERS AND SQUALLS.
A TIGHT PRES GRADIENT WILL BRING GUSTY WINDS UP TO 25KTS THIS
AFTERNOON AS DIURNAL HEATING/MIXING WITHIN DEEPENING BOUNDARY
ALLOWS WINDS ALOFT TO MIX TO GROUND LEVEL.
ARRIVAL OF SFC RIDGE SHOULD BRING WIDESPREAD VFR CONDS AND
DIMINISHING WIND TO CENTRAL PA THIS EVENING.
OUTLOOK...
FRI...PM SHSN/VIS REDUCTIONS LIKELY...ESP W MTNS.
SAT...WINDY. SHSN/REDUCED VIS POSS W MTNS...MAINLY AM.
SUN...NO SIG WX EXPECTED.
MON...PM SNOW POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THIS EVENING FOR
PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ010-017-024-033.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...STEINBUGL
AVIATION...ROSS/LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1035 AM EST THU FEB 11 2016
.SYNOPSIS...
A PERSISTENT NORTHWEST WIND WILL KEEP LAKE EFFECT AND UPSLOPE
SNOW SHOWERS GOING ALL DAY. AN ARCTIC BLAST WILL DELIVER THE
COLDEST AIR OF THE SEASON FOR VALENTINES WEEKEND WITH DANGEROUS
COLD AND WIND CHILLS EXPECTED TO IMPACT THE AREA SATURDAY INTO
SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
840 AM UPDATE...
MULTIPLE NARROW BANDS OF SNOW SQUALLS CONTINUE TO STREAM SE AND
WELL INLAND FROM THE GLAKES THIS MORNING...MAKING IT ALL THE WAY
INTO PORTIONS OF THE LOWER SUSQ VALLEY REGION. BRIEF...GREATLY
REDUCED VSBYS POSE A SIGNIF IMPACT TO TRAVEL WITHIN THESE VERY
NARROW BUT RATHER INTENSE SNOW BANDS THAT COULD DROP UP TO ONE
INCH OF FLUFF IN JUST A 15-20 MINUTE PERIOD.
LATEST HRRR AND LOW-MID LEVEL LAPSE RATES VIA THE NAM INDICATE
THAT THE TARGET AREA FOR ONE OR TWO EXTENSIVE/INTENSE SQUALL BANDS
SHOULD SHIFT TO THE NE HALF OF THE CWA THIS AFTERNOON AS MEAN BLYR
WINDS BACK JUST 5-10 DEGREES. THESE SNOW BANDS WILL CONTINUE TO
HAVE A GOOD DUAL LAKE CONNECTION FLOWING OVER THE LONG AXIS OF
LAKE HURON. WILL FORECAST MAINLY A COATING TO ONE INCH ALONG AND
NORTH OF A LINE FROM KUNV TO KSEG...HOWEVER SOME LOCATIONS IN THE
CENTRAL MTNS AND WEST BRANCH/MIDDLE SUSQ VALLEY COULD SEE ANOTHER
QUICK 2-3 INCHES OF FLUFFY/WIND BLOWN SNOW BETWEEN 14Z AND 23Z.
SOME LOCATIONS MAY NEED TO BE PLACED IN A SHORT FUSED WINT
WEATHER ADVIS DEPENDING ON EXACTLY WHERE THIS MESOSCALE FEATURE
SETS UP.
WILL MAINTAIN CURRENT WINTER WEATHER ADVISORIES OVER THE LAURELS
AND WRN MTNS...AND LES WARNINGS AND ADVISORIES FOR THE FAR NW
SNOWBELT.
THE WIND WILL MAKE IT FEEL MUCH COLDER TODAY WITH WIND CHILLS
BETWEEN -10 AND +10 ACROSS THE ENTIRE AREA ALL DAY LONG. THE
BLUSTERY CONDITIONS WILL JUST BE A TASTE OF WHAT LOOKS LIKE IS ON
THE HORIZON FOR SATURDAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
THE SNOW SHOWERS DO BEGIN TO TAPER OFF IN THE LATE AFTN AND
EVENING. THE ACCUMS SHOULD BECOME NEGLIGABLE NOT TOO LONG AFTER
SUNSET. THE END TIMING OF THE ADVYS/WARNING WILL BE KEPT AS IS AT
03Z. HOWEVER...MANY PLACES S OF ELK CO WILL SEE JUST A FLURRY OR
TWO IN THE EVENING. TEMPS DROP INTO THE SINGLE DIGITS TONIGHT AS
SOME CLEARING TAKES PLACE IN THE NW...BUT THE CALM AIR IN THE SE
COULD CAUSE THE TEMPS THERE TO BECOME COLDER. SNOW PACK AND CALM
AIR DO WONDERS TO MAKE IT COLDER THAN WE THINK IT WILL BE. WILL
PAINT IN A DIP AROUND THE TYPICAL FRIDGES OF SEG AND THV - MAKING
THEM 3-5F COLDER THAN THE SURROUNDING LOCALES.
THE FIRST PART OF FRIDAY SHOULD BE QUIET SAVE A QUICK INCREASE IN
CLOUDS FROM THE SW AS SOME MEAGER WARM ADVECTION KICKS IN AHEAD OF
THE WELL-ADVERTISED ARCTIC FRONT. SOME LIGHT SNOW WILL PROBABLY
BREAK OUT/SLIDE IN DURING THE AFTN. TEMPS WILL TRY TO GET INTO THE
20S ALL OVER BUT THE PERSISTENT CLOUD COVER IN THE NW WILL LIKELY
KEEP THEM U20.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS LIKELY WITH ARCTIC FRONT
FRIDAY NIGHT-SATURDAY. FRIGID TEMPERATURES AND DANGEROUS WIND
CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
EASTERN US INTO NEXT WEEK. EMERGENCE OF SOUTHERN STREAM SHORTWAVE
AND ITS INTERACTION WITH THE NORTHERN STREAM FLOW CREATES THE
POTENTIAL FOR WINTER PRECIPITATION MON-WED BUT WITH A HIGH DEGREE
OF UNCERTAINTY/LOW CONFIDENCE. A PATTERN SHIFT TO PACIFIC ZONAL-TO
SOUTHWEST FLOW ALOFT WITH RISING/ABOVE NORMAL HEIGHTS IS FCST BY
THE END OF NEXT WEEK. THIS FAVORS A RETURN TO MILDER WEATHER.
LAKE EFFECT AND UPSLOPE SNOW SHOWERS CONTINUE INTO THE WEEKEND
BEFORE TAPERING OFF ON SUNDAY...AS ARCTIC HIGH BUILDS OVER THE
REGION. ADDITIONAL LIGHT SNOW ACCUMULATIONS ARE LIKELY IN THE
FAVORED NORTHWEST SNOWBELT AND HIGHER TERRAIN ALONG THE
ALLEGHENIES/LAUREL HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
LIKELY WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM 0F IN THE LOWER SUSQ. VALLEY
TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA. WIND
CHILL HEADLINES ARE A GOOD BET AND PRECAUTIONS SHOULD BE MADE NOW
TO PROTECT/PREPARE FOR THE UPCOMING COLD SNAP.
A MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT WEEK.
THERE IS STILL A LOT OF SPREAD CONCERNING A POTENTIAL STORM SYSTEM
IMPACTING THE NORTHEAST EARLY NEXT WEEK. THE OPERATIONAL EC
REMAINS MORE BULLISH THAN THE GFS IN DEVELOPING A SIGNIFICANT
CYCLONE AND HAS TRENDED EVEN FURTHER TO THE WEST WITH IS 10/12Z
RUN. CONFIDENCE REMAINS LOW BUT THE SYSTEM WILL NEED TO BE MONITORED.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
LAKE ENHANCED OROGRAPHIC SNOW WILL RESULT IN MAINLY IFR VSBYS AT
KBFD/KJST FEW NEXT SEVERAL HOURS. DRYING/DOWNSLOPING FLOW WILL
RESULT IN PROGRESSIVELY MORE FAVORABLE CONDS EAST OF THE
MTNS...WITH OCNL MVFR CIGS/FLURRIES POSSIBLE AT KAOO/KUNV AND A
HIGH CONFIDENCE OF PREDOMINATELY VFR CONDS AT KIPT/KMDT/KLNS. SFC
RIDGE BUILDING IN FROM THE OHIO VALLEY SHOULD CAUSE LAKE EFFECT
SNOW SHOWERS TO DWINDLE THIS AFTN...WITH PREDOMINANTLY MVFR CONDS
RETURNING TO KBFD/KJST AND VFR ELSEWHERE.
A TIGHT PRES GRADIENT WILL BRING GUSTY WINDS UP TO 25KTS THIS
AFTERNOON AS DIURNAL HEATING/MIXING WITHIN DEEPENING BOUNDARY
ALLOWS WINDS ALOFT TO MIX TO GROUND LEVEL.
ARRIVAL OF SFC RIDGE SHOULD BRING WIDESPREAD VFR CONDS AND
DIMINISHING WIND TO CENTRAL PA THIS EVENING.
OUTLOOK...
FRI...PM SHSN/VIS REDUCTIONS LIKELY...ESP W MTNS.
SAT...WINDY. SHSN/REDUCED VIS POSS W MTNS...MAINLY AM.
SUN...NO SIG WX EXPECTED.
MON...PM SNOW POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THIS EVENING FOR
PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ010-017-024-033.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...ROSS/FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
856 AM EST THU FEB 11 2016
.SYNOPSIS...
A PERSISTENT NORTHWEST WIND WILL KEEP LAKE EFFECT AND UPSLOPE
SNOW SHOWERS GOING ALL DAY. AN ARCTIC BLAST WILL DELIVER THE
COLDEST AIR OF THE SEASON FOR VALENTINES WEEKEND WITH DANGEROUS
COLD AND WIND CHILLS EXPECTED TO IMPACT THE AREA SATURDAY INTO
SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
840 AM UPDATE...
MULTIPLE NARROW BANDS OF SNOW SQUALLS CONTINUE TO STREAM SE AND
WELL INLAND FROM THE GLAKES THIS MORNING...MAKING IT ALL THE WAY
INTO PORTIONS OF THE LOWER SUSQ VALLEY REGION. BRIEF...GREATLY
REDUCED VSBYS POSE A SIGNIF IMPACT TO TRAVEL WITHIN THESE VERY
NARROW BUT RATHER INTENSE SNOW BANDS THAT COULD DROP UP TO ONE
INCH OF FLUFF IN JUST A 15-20 MINUTE PERIOD.
LATEST HRRR AND LOW-MID LEVEL LAPSE RATES VIA THE NAM INDICATE
THAT THE TARGET AREA FOR ONE OR TWO EXTENSIVE/INTENSE SQUALL BANDS
SHOULD SHIFT TO THE NE HALF OF THE CWA THIS AFTERNOON AS MEAN BLYR
WINDS BACK JUST 5-10 DEGREES. THESE SNOW BANDS WILL CONTINUE TO
HAVE A GOOD DUAL LAKE CONNECTION FLOWING OVER THE LONG AXIS OF
LAKE HURON. WILL FORECAST MAINLY A COATING TO ONE INCH ALONG AND
NORTH OF A LINE FROM KUNV TO KSEG...HOWEVER SOME LOCATIONS IN THE
CENTRAL MTNS AND WEST BRANCH/MIDDLE SUSQ VALLEY COULD SEE ANOTHER
QUICK 2-3 INCHES OF FLUFFY/WIND BLOWN SNOW BETWEEN 14Z AND 23Z.
SOME LOCATIONS MAY NEED TO BE PLACED IN A SHORT FUSED WINT
WEATHER ADVIS DEPENDING ON EXACTLY WHERE THIS MESOSCALE FEATURE
SETS UP.
WILL MAINTAIN CURRENT WINTER WEATHER ADVISORIES OVER THE LAURELS
AND WRN MTNS...AND LES WARNINGS AND ADVISORIES FOR THE FAR NW
SNOWBELT.
THE WIND WILL MAKE IT FEEL MUCH COLDER TODAY WITH WIND CHILLS
BETWEEN -10 AND +10 ACROSS THE ENTIRE AREA ALL DAY LONG. THE
BLUSTERY CONDITIONS WILL JUST BE A TASTE OF WHAT LOOKS LIKE IS ON
THE HORIZON FOR SATURDAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
THE SNOW SHOWERS DO BEGIN TO TAPER OFF IN THE LATE AFTN AND
EVENING. THE ACCUMS SHOULD BECOME NEGLIGABLE NOT TOO LONG AFTER
SUNSET. THE END TIMING OF THE ADVYS/WARNING WILL BE KEPT AS IS AT
03Z. HOWEVER...MANY PLACES S OF ELK CO WILL SEE JUST A FLURRY OR
TWO IN THE EVENING. TEMPS DROP INTO THE SINGLE DIGITS TONIGHT AS
SOME CLEARING TAKES PLACE IN THE NW...BUT THE CALM AIR IN THE SE
COULD CAUSE THE TEMPS THERE TO BECOME COLDER. SNOW PACK AND CALM
AIR DO WONDERS TO MAKE IT COLDER THAN WE THINK IT WILL BE. WILL
PAINT IN A DIP AROUND THE TYPICAL FRIDGES OF SEG AND THV - MAKING
THEM 3-5F COLDER THAN THE SURROUNDING LOCALES.
THE FIRST PART OF FRIDAY SHOULD BE QUIET SAVE A QUICK INCREASE IN
CLOUDS FROM THE SW AS SOME MEAGER WARM ADVECTION KICKS IN AHEAD OF
THE WELL-ADVERTISED ARCTIC FRONT. SOME LIGHT SNOW WILL PROBABLY
BREAK OUT/SLIDE IN DURING THE AFTN. TEMPS WILL TRY TO GET INTO THE
20S ALL OVER BUT THE PERSISTENT CLOUD COVER IN THE NW WILL LIKELY
KEEP THEM U20.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS LIKELY WITH ARCTIC FRONT
FRIDAY NIGHT-SATURDAY. FRIGID TEMPERATURES AND DANGEROUS WIND
CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
EASTERN US INTO NEXT WEEK. EMERGENCE OF SOUTHERN STREAM SHORTWAVE
AND ITS INTERACTION WITH THE NORTHERN STREAM FLOW CREATES THE
POTENTIAL FOR WINTER PRECIPITATION MON-WED BUT WITH A HIGH DEGREE
OF UNCERTAINTY/LOW CONFIDENCE. A PATTERN SHIFT TO PACIFIC ZONAL-TO
SOUTHWEST FLOW ALOFT WITH RISING/ABOVE NORMAL HEIGHTS IS FCST BY
THE END OF NEXT WEEK. THIS FAVORS A RETURN TO MILDER WEATHER.
LAKE EFFECT AND UPSLOPE SNOW SHOWERS CONTINUE INTO THE WEEKEND
BEFORE TAPERING OFF ON SUNDAY...AS ARCTIC HIGH BUILDS OVER THE
REGION. ADDITIONAL LIGHT SNOW ACCUMULATIONS ARE LIKELY IN THE
FAVORED NORTHWEST SNOWBELT AND HIGHER TERRAIN ALONG THE
ALLEGHENIES/LAUREL HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
LIKELY WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM 0F IN THE LOWER SUSQ. VALLEY
TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA. WIND
CHILL HEADLINES ARE A GOOD BET AND PRECAUTIONS SHOULD BE MADE NOW
TO PROTECT/PREPARE FOR THE UPCOMING COLD SNAP.
A MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT WEEK.
THERE IS STILL A LOT OF SPREAD CONCERNING A POTENTIAL STORM SYSTEM
IMPACTING THE NORTHEAST EARLY NEXT WEEK. THE OPERATIONAL EC
REMAINS MORE BULLISH THAN THE GFS IN DEVELOPING A SIGNIFICANT
CYCLONE AND HAS TRENDED EVEN FURTHER TO THE WEST WITH IS 10/12Z
RUN. CONFIDENCE REMAINS LOW BUT THE SYSTEM WILL NEED TO BE MONITORED.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
LAKE ENHANCED OROGRAPHIC SNOW WILL RESULT IN PREDOMINANTLY IFR
VSBYS AT KBFD/KJST THIS MORNING. DRYING/DOWNSLOPING FLOW WILL
RESULT IN PROGRESSIVELY MORE FAVORABLE CONDS EAST OF THE MTNS...WITH
OCNL MVFR CIGS/FLURRIES POSSIBLE AT KAOO/KUNV AND A HIGH CONFIDENCE
OF PREDOMINATELY VFR CONDS AT KIPT/KMDT/KLNS. SFC RIDGE BUILDING
IN FROM THE OHIO VALLEY SHOULD CAUSE LAKE EFFECT SNOW SHOWERS TO
DWINDLE BY THIS AFTN...WITH PREDOMINANTLY MVFR CONDS RETURNING TO
KBFD/KJST AND VFR ELSEWHERE.
A TIGHT PRES GRADIENT OVR THE REGION IS ALREADY PRODUCING
GUSTS IN EXCESS OF 20KTS ACROSS PARTS OF CENTRAL PA AT 12Z...AND
MDL SOUNDINGS INDICATE GUSTS TO ARND 25KTS WILL BECOME WIDESPREAD
BY LATE AM...AS DIURNAL HEATING/MIXING WITHIN DEEPENING BOUNDARY
ALLOWS WINDS ALOFT TO MIX TO GROUND LEVEL.
ARRIVAL OF SFC RIDGE SHOULD BRING WIDESPREAD VFR CONDS AND
DIMINISHING WIND TO CENTRAL PA THIS EVENING.
OUTLOOK...
FRI...PM SHSN/VIS REDUCTIONS LIKELY...ESP W MTNS.
SAT...WINDY. SHSN/REDUCED VIS POSS W MTNS...MAINLY AM.
SUN...NO SIG WX EXPECTED.
MON...PM SNOW POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THIS EVENING FOR
PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ010-017-024-033.
&&
$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
248 AM EST THU FEB 11 2016
.SYNOPSIS...
A PERSISTENT NORTHWEST FLOW WILL BRING A PROLONGED PERIOD OF LAKE
EFFECT AND UPSLOPE SNOW SHOWERS THROUGHOUT THE NORTHWEST SNOWBELT
AND ACROSS THE LAUREL HIGHLANDS. AN ARCTIC BLAST WILL DELIVER THE
COLDEST AIR OF THE SEASON FOR VALENTINES WEEKEND WITH DANGEROUS
COLD AND WIND CHILLS EXPECTED TO IMPACT THE AREA SATURDAY INTO
SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
IN THE NEAR TERM...OUR LINE OF SNOW SHOWERS AND SQUALLS HAS BEGUN
TO WEAKEN AND BECOME MORE DISORGANIZED...MORE OR LESS ALONG THE
LINES OF THE HIGH RES MESO MODELS. STILL LOOKING AT THE
POSSIBILITY OF A QUICK COATING OF SNOW IN A FEW LOCATIONS AS THIS
FEATURE SLIDES OFF TO THE SOUTHEAST.
FOR THE LARGER PICTURE...PERSISTENT UPSLOPE SNOW SHOWERS AND
FREQUENT LES FROM MEANDERING SNOW BANDS ACROSS THE FAR NW ZONES
WILL BRING AN ADDITIONAL 1 TO 2 INCHES EVERY 4 TO 6 HOURS THROUGH
TONIGHT...THOUGH PORTIONS OF NW WARREN COUNTY COULD SEE NEARLY
DOUBLE THOSE SNOWFALL RATES.
THE WELL-ALIGNED SFC-800 MB FLOW FROM ABOUT 270 DEGREES...WILL
VEER TO ABOUT 295 DEG OVERNIGHT AS A SECONDARY COLD FRONT SWINGS
SE THROUGH THE AREA.
BASED ON THE MODERATELY STRONG...WELL ALIGNED...AND PERSISTENT 280-290
DEG FLOW THROUGH ABOUT 04Z FRIDAY...WE EXTENDED THE WINTER WX AND
LES ADVISORIES AND WARNINGS OUT IN TIME THROUGH 03Z FRIDAY...AND
EXPANDED THE WINT WX ADVIS NORTH TO COVER ELK AND CLEARFIELD
COUNTIES.
LATER TONIGHT...LOOK FOR VARIABLE AMOUNTS OF CLOUDS WITH SCATTERED
FLURRIES ACROSS THE SUSQ VALLEY AND SOUTHERN TIER...WHILE A FEW
BRIEF SNOW SHOWERS IN NARROW NW-SE STREAMERS OFF LAKE ERIE COULD
ADD AN ADDITIONAL LIGHT COATING FROM KAOO TO KUNV.
LOWS TONIGHT WILL VARY FROM 5-10F ACROSS THE NORTHERN AND WESTERN
MTNS...TO THE UPPER TEENS IN THE SUSQ VALLEY. WIND CHILLS COULD
DIP TO NEAR -10F AT TIMES LATE TONIGHT ACROSS THE NRN AND WRN
MTNS...AND IN THE ZERO TO 10 ABOVE RANGE ACROSS THE CENTRAL AND SE
ZONES...BUT WILL BE A GOOD 5 TO 10 DEG F ABOVE WIND CHILL ADVISORY
CRITERIA IN ANY OF THESE LOCATIONS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
PERSISTENT...MEAN BLYR FLOW FROM 280-290 DEGREES WILL LEAD TO
WIDESPREAD STRATO CU WITH CLOUD TEMPS ACROSS MUCH OF CENTRAL PENN
FALLING WITHIN THE FAVORABLE DGZ OF -12 TO -18C.
THIS WILL LEAD TO WIDESPREAD FLURRIES AND BRIEF SNOW SHOWERS FROM
NARROW...AND SLOWLY MEANDERING BANDS. MESOSCALE MODELS SUCH AS
THE HRRR AND 3 KM NCAR ENSEMBLE WILL PLAY AN IMPORTANT ROLE IN
FORECASTING THE LOCATION...MVMT...AND SNOW FROM THESE FAIRLY WELL-
ORGANIZED BUT NARROW SNOW BANDS THAT WILL REACH INTO THE CENTRAL
RIDGE AND VALLEY REGION AT TIMES.
ADDITIONAL SNOW ACCUMS OF A FEW TO SEVERAL INCHES WILL OCCUR
DURING THE DAYLIGHT HOURS THURSDAY ACROSS THE NW MTNS AND LAUREL
HIGHLANDS WHERE THE WINT WX AND LES ADVISORIES...AND LES WARNINGS
WILL CONTINUE.
MAX TEMPS THURSDAY WILL BE ONLY 12-25F WHICH IS AROUND 15 DEG F
BELOW NORMAL FOR THIS TIME OF YEAR.
THE BULK OF THE MORE SIGNIFICANT SNOW SHOWERS/LES SHOULD TAPER
OFF/LIFT TO THE NORTH...CLOSELY HUGGING THE I-90 CORRIDOR AS MEAN
BLYR WINDS BACK MORE TO THE WSW AFTER MIDNIGHT.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS LIKELY WITH ARCTIC FRONT
FRIDAY NIGHT-SATURDAY. FRIGID TEMPERATURES AND DANGEROUS WIND
CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
EASTERN US INTO NEXT WEEK. EMERGENCE OF SOUTHERN STREAM SHORTWAVE
AND ITS INTERACTION WITH THE NORTHERN STREAM FLOW CREATES THE
POTENTIAL FOR WINTER PRECIPITATION MON-WED BUT WITH A HIGH DEGREE
OF UNCERTAINTY/LOW CONFIDENCE. A PATTERN SHIFT TO PACIFIC ZONAL-TO
SOUTHWEST FLOW ALOFT WITH RISING/ABOVE NORMAL HEIGHTS IS FCST BY
THE END OF NEXT WEEK. THIS FAVORS A RETURN TO MILDER WEATHER.
LAKE EFFECT AND UPSLOPE SNOW SHOWERS CONTINUE INTO THE WEEKEND
BEFORE TAPERING OFF ON SUNDAY...AS ARCTIC HIGH BUILDS OVER THE
REGION. ADDITIONAL LIGHT SNOW ACCUMULATIONS ARE LIKELY IN THE
FAVORED NORTHWEST SNOWBELT AND HIGHER TERRAIN ALONG THE
ALLEGHENIES/LAUREL HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
LIKELY WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM 0F IN THE LOWER SUSQ. VALLEY
TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA. WIND
CHILL HEADLINES ARE A GOOD BET AND PRECAUTIONS SHOULD BE MADE NOW
TO PROTECT/PREPARE FOR THE UPCOMING COLD SNAP.
A MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT WEEK.
THERE IS STILL A LOT OF SPREAD CONCERNING A POTENTIAL STORM SYSTEM
IMPACTING THE NORTHEAST EARLY NEXT WEEK. THE OPERATIONAL EC
REMAINS MORE BULLISH THAN THE GFS IN DEVELOPING A SIGNIFICANT
CYCLONE AND HAS TRENDED EVEN FURTHER TO THE WEST WITH IS 10/12Z
RUN. CONFIDENCE REMAINS LOW BUT THE SYSTEM WILL NEED TO BE MONITORED.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
LAKE ENHANCED OROGRAPHIC SNOW WILL RESULT IN PREDOMINANTLY IFR
VSBYS AT KBFD/KJST THIS MORNING. A SLOW MOVING SFC TROUGH LYING
ACROSS CENTRAL PA WILL ALSO PRODUCE OCNL IFR VSBYS AT KUNV UNTIL
IT/S PASSAGE ARND 11Z.
AFTER PASSAGE OF SFC TROUGH...EXPECT A TYPICAL LAKE EFFECT REGIME
BTWN 11Z-17Z...WITH PREDOMINANTLY IFR VSBYS FROM LGT SNOW AT
KBFD/KJST...POSSIBLE MVFR CIGS AT KAOO/KUNV AND A HIGH CONFIDENCE
OF VFR CONDS AT THE LOWER ELEV AIRFIELDS FURTHER EAST...INCLUDING
KIPT/KMDT/KLNS. SFC RIDGE BUILDING IN FROM THE OHIO VALLEY SHOULD
CAUSE LAKE EFFECT SNOW SHOWERS TO DWINDLE BY THIS AFTN...WITH
PREDOMINANTLY MVFR CONDS RETURNING TO KBFD/KJST AND VFR
ELSEWHERE.
A TIGHT PRES GRADIENT OVR THE REGION IS ALREADY PRODUCING
GUSTS IN EXCESS OF 25KTS AT KJST EARLY THIS AM...AND MDL SOUNDINGS
INDICATE SIMILAR GUSTS WILL DEVELOP ACROSS THE REST OF CENTRAL PA
BY LATE AM...AS DIURNAL HEATING/MIXING WITHIN DEEPENING BOUNDARY
ALLOWS WINDS ALOFT TO MIX TO GROUND LEVEL.
ARRIVAL OF SFC RIDGE SHOULD BRING WIDESPREAD VFR CONDS AND
DIMINISHING WIND TO CENTRAL PA THIS EVENING.
OUTLOOK...
FRI...PM SHSN/VIS REDUCTIONS LIKELY...ESP W MTNS.
SAT...WINDY. SHSN/REDUCED VIS POSS W MTNS...MAINLY AM.
SUN...NO SIG WX EXPECTED.
MON...PM SNOW POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THIS EVENING FOR
PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ010-017-024-033.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1200 AM EST THU FEB 11 2016
.SYNOPSIS...
A PERSISTENT NORTHWEST FLOW WILL BRING A PROLONGED PERIOD OF LAKE
EFFECT AND UPSLOPE SNOW SHOWERS THROUGHOUT THE NORTHWEST SNOWBELT
AND ACROSS THE LAUREL HIGHLANDS. AN ARCTIC BLAST WILL DELIVER THE
COLDEST AIR OF THE SEASON FOR VALENTINES WEEKEND WITH DANGEROUS
COLD AND WIND CHILLS EXPECTED TO IMPACT THE AREA SATURDAY INTO
SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
IN THE NEAR TERM...OUR LINE OF SNOW SHOWERS AND SQUALLS HAS BEGUN
TO WEAKEN AND BECOME MORE DISORGANIZED...MORE OR LESS ALONG THE
LINES OF THE HIGH RES MESO MODELS. STILL LOOKING AT THE
POSSIBILITY OF A QUICK COATING OF SNOW IN A FEW LOCATIONS AS THIS
FEATURE SLIDES OFF TO THE SOUTHEAST.
FOR THE LARGER PICTURE...PERSISTENT UPSLOPE SNOW SHOWERS AND
FREQUENT LES FROM MEANDERING SNOW BANDS ACROSS THE FAR NW ZONES
WILL BRING AN ADDITIONAL 1 TO 2 INCHES EVERY 4 TO 6 HOURS THROUGH
TONIGHT...THOUGH PORTIONS OF NW WARREN COUNTY COULD SEE NEARLY
DOUBLE THOSE SNOWFALL RATES.
THE WELL-ALIGNED SFC-800 MB FLOW FROM ABOUT 270 DEGREES...WILL
VEER TO ABOUT 295 DEG OVERNIGHT AS A SECONDARY COLD FRONT SWINGS
SE THROUGH THE AREA.
BASED ON THE MODERATELY STRONG...WELL ALIGNED...AND PERSISTENT 280-290
DEG FLOW THROUGH ABOUT 04Z FRIDAY...WE EXTENDED THE WINTER WX AND
LES ADVISORIES AND WARNINGS OUT IN TIME THROUGH 03Z FRIDAY...AND
EXPANDED THE WINT WX ADVIS NORTH TO COVER ELK AND CLEARFIELD
COUNTIES.
LATER TONIGHT...LOOK FOR VARIABLE AMOUNTS OF CLOUDS WITH SCATTERED
FLURRIES ACROSS THE SUSQ VALLEY AND SOUTHERN TIER...WHILE A FEW
BRIEF SNOW SHOWERS IN NARROW NW-SE STREAMERS OFF LAKE ERIE COULD
ADD AN ADDITIONAL LIGHT COATING FROM KAOO TO KUNV.
LOWS TONIGHT WILL VARY FROM 5-10F ACROSS THE NORTHERN AND WESTERN
MTNS...TO THE UPPER TEENS IN THE SUSQ VALLEY. WIND CHILLS COULD
DIP TO NEAR -10F AT TIMES LATE TONIGHT ACROSS THE NRN AND WRN
MTNS...AND IN THE ZERO TO 10 ABOVE RANGE ACROSS THE CENTRAL AND SE
ZONES...BUT WILL BE A GOOD 5 TO 10 DEG F ABOVE WIND CHILL ADVISORY
CRITERIA IN ANY OF THESE LOCATIONS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
PERSISTENT...MEAN BLYR FLOW FROM 280-290 DEGREES WILL LEAD TO
WIDESPREAD STRATO CU WITH CLOUD TEMPS ACROSS MUCH OF CENTRAL PENN
FALLING WITHIN THE FAVORABLE DGZ OF -12 TO -18C.
THIS WILL LEAD TO WIDESPREAD FLURRIES AND BRIEF SNOW SHOWERS FROM
NARROW...AND SLOWLY MEANDERING BANDS. MESOSCALE MODELS SUCH AS
THE HRRR AND 3 KM NCAR ENSEMBLE WILL PLAY AN IMPORTANT ROLE IN
FORECASTING THE LOCATION...MVMT...AND SNOW FROM THESE FAIRLY WELL-
ORGANIZED BUT NARROW SNOW BANDS THAT WILL REACH INTO THE CENTRAL
RIDGE AND VALLEY REGION AT TIMES.
ADDITIONAL SNOW ACCUMS OF A FEW TO SEVERAL INCHES WILL OCCUR
DURING THE DAYLIGHT HOURS THURSDAY ACROSS THE NW MTNS AND LAUREL
HIGHLANDS WHERE THE WINT WX AND LES ADVISORIES...AND LES WARNINGS
WILL CONTINUE.
MAX TEMPS THURSDAY WILL BE ONLY 12-25F WHICH IS AROUND 15 DEG F
BELOW NORMAL FOR THIS TIME OF YEAR.
THE BULK OF THE MORE SIGNIFICANT SNOW SHOWERS/LES SHOULD TAPER
OFF/LIFT TO THE NORTH...CLOSELY HUGGING THE I-90 CORRIDOR AS MEAN
BLYR WINDS BACK MORE TO THE WSW AFTER MIDNIGHT.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
*IMPACT WEATHER HIGHLIGHTS: SNOW SQUALLS LIKELY WITH ARCTIC FRONT
FRIDAY NIGHT-SATURDAY. FRIGID TEMPERATURES AND DANGEROUS WIND
CHILLS FOR VALENTINES WEEKEND.
POLAR VORTEX DIVES FROM HUDSON BAY SOUTHEAST ACROSS QUEBEC AND
NORTHERN NEW ENGLAND THURSDAY-SUNDAY. THE GLOBAL MODELS AND
ENSEMBLE MEANS KEEP A `MILDER` TROUGH PATTERN IN PLACE OVER THE
EASTERN US INTO NEXT WEEK. EMERGENCE OF SOUTHERN STREAM SHORTWAVE
AND ITS INTERACTION WITH THE NORTHERN STREAM FLOW CREATES THE
POTENTIAL FOR WINTER PRECIPITATION MON-WED BUT WITH A HIGH DEGREE
OF UNCERTAINTY/LOW CONFIDENCE. A PATTERN SHIFT TO PACIFIC ZONAL-TO
SOUTHWEST FLOW ALOFT WITH RISING/ABOVE NORMAL HEIGHTS IS FCST BY
THE END OF NEXT WEEK. THIS FAVORS A RETURN TO MILDER WEATHER.
LAKE EFFECT AND UPSLOPE SNOW SHOWERS CONTINUE INTO THE WEEKEND
BEFORE TAPERING OFF ON SUNDAY...AS ARCTIC HIGH BUILDS OVER THE
REGION. ADDITIONAL LIGHT SNOW ACCUMULATIONS ARE LIKELY IN THE
FAVORED NORTHWEST SNOWBELT AND HIGHER TERRAIN ALONG THE
ALLEGHENIES/LAUREL HIGHLANDS.
THE COLDEST AIRMASS OF THE 2015-16 WINTER SEASON REMAINS POISED
TO ARRIVE THIS WEEKEND...AS A BLAST OF ARCTIC AIR DELIVERS A SHORT
DURATION COLD OUTBREAK TO CENTRAL PENNSYLVANIA. SNOW SQUALLS ARE
LIKELY WITH THE ARCTIC FRONTAL PASSAGE FRIDAY NIGHT INTO SATURDAY.
MAX/MIN TEMPERATURE DEPARTURES OF -20 TO -25 DEGREES BELOW CLIMO
ARE FCST SATURDAY AND SUNDAY. MINIMUM TEMPERATURES SATURDAY NIGHT
INTO EARLY SUNDAY MORNING RANGE FROM 0F IN THE LOWER SUSQ. VALLEY
TO -10F IN THE NORTHWEST ALLEGHENIES. THE FRIGID TEMPERATURES
COMBINED WITH DANGEROUS WIND CHILLS /-10 TO -25 BELOW ZERO/ WILL
RESULT IN AN INCREASED RISK FOR FROSTBITE AND HYPOTHERMIA. WIND
CHILL HEADLINES ARE A GOOD BET AND PRECAUTIONS SHOULD BE MADE NOW
TO PROTECT/PREPARE FOR THE UPCOMING COLD SNAP.
A MODERATION (WARMING TREND) IS EXPECTED INTO EARLY NEXT WEEK.
THERE IS STILL A LOT OF SPREAD CONCERNING A POTENTIAL STORM SYSTEM
IMPACTING THE NORTHEAST EARLY NEXT WEEK. THE OPERATIONAL EC
REMAINS MORE BULLISH THAN THE GFS IN DEVELOPING A SIGNIFICANT
CYCLONE AND HAS TRENDED EVEN FURTHER TO THE WEST WITH IS 10/12Z
RUN. CONFIDENCE REMAINS LOW BUT THE SYSTEM WILL NEED TO BE MONITORED.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
OVERALL VFR CIGS AND VBSYS WILL BEGIN TO DOMINATE OVERNIGHT. THE
SNOW CONVECTION SWITCHED FROM A WAVE TO A LINEAR BAND FEATURE. THE
HRRR DID A DECENT JOB OF SHOWING THE SWITCH...HOWEVER FAILED TO
SHOW THE INTENSITY. THE BIGGEST ISSUE WILL BE THE GUSTY WINDS
INTERACTION WITH ANY SNOW...WHICH COULD THEN BRING MVFR OR LOWER
VSBYS. THE BAND SHOULD BRIEFLY MOVE OVER UNV...BETWEEN 05 TO 07Z.
OTHERWISE VFR SHOULD DOMINATE THROUGH THE CENTRAL AND WESTERN TAF
SITES. BFD AND JST SHOULD REMAIN MAINLY MVFR WITH PERIODS OF IFR
POSSIBLE THROUGH THE FIRST HALF OF TOMORROW MORNING AND WILL
SLOWLY FADE BY TOMORROW EVENING.
OUTLOOK...
THU/THU NIGHT...MVFR WITH PERIODS OF IFR IN -SHSN ACROSS THE WRN
PENN MTNS. MAINLY VFR ELSEWHERE.
FRI...MVFR IN -SHSN...MAINLY LATE WITH STRONG COLD FRONT.
SAT...MVFR IN -SHSN W MTNS. VFR OTHERWISE. WINDY.
SUN...MVFR IN -SHSN IN W MTNS EARLY...OTHERWISE VFR.
MON...VFR POSSIBLE EARLY ACROSS THE EASTERN HALF OF PENN...THEN
LOWERING AND THICKENING CLOUDS LIKELY WITH A FEW PERIODS OF SNOW
POSSIBLE...YIELDING MVFR TO IFR VSBYS AND CIGS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THURSDAY FOR PAZ005.
LAKE EFFECT SNOW WARNING UNTIL 10 PM EST THURSDAY FOR PAZ004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THURSDAY FOR PAZ010-
017-024-033.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LAMBERT/CERU
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
914 PM CST FRI FEB 12 2016
.DISCUSSION...DEWPOINT TEMPERATURES HAVE RISEN TO THE UPPER 50S
TO NEAR 60 OVER THE COASTAL PLAINS THIS EVENING. WINDS WILL
CONTINUE TO DIMINISH TONIGHT AS A WEAK FRONTAL BOUNDARY FROM
NORTH OF HOUSTON TO SOUTH OF SAN ANTONIO REMAINS ESSENTIAL
QUASISTATIONARY TONIGHT. TEMP-DEWPOINT DEPRESSIONS WERE THE
LOWEST AROUND THE MID COAST AT 03Z. 00Z HRRR ALONG WITH 00Z
NAM SHOW FOG WILL FORM OVER THE MID COAST REGION INITIALLY
JUST AFTER 06Z AND SPREAD WESTWARD INTO THE BRUSH COUNTRY
OVERNIGHT. ADDED CALHOUN AND ARANSAS COUNTIES INTO THE DENSE
FOG ADVISORY. MAY NEED TO HAVE ADVISORY FOR WEBB AND LA SALLE
COUNTIES LATER TONIGHT BUT NOT CONFIDENT ENOUGH AT THIS POINT
TO INCLUDE IN THE ADVISORY.
&&
.PREV DISCUSSION... /ISSUED 601 PM CST FRI FEB 12 2016/
DISCUSSION...SEE AVIATION SECTION FOR 00Z TAFS.
AVIATION...SEA BREEZE BOUNDARY WILL CONTINUE TO PUSH INLAND
DURING THE EVENING HOURS...ALREADY PAST VCT AND ALI. HIGHER
BOUNDARY LAYER MOISTURE WILL BE OVER THE COASTAL PLAINS INTO
THE EASTERN BRUSH COUNTRY BY 06Z WHILE WINDS BECOME LIGHT.
FOG/MVFR VSBYS EXPECTED TO DEVELOP 05-06Z IN THIS REGION
WITH CONDITIONS DETERIORATING TO LIFR WITH DENSE FOG BY
07-08Z AND CONTINUE UNTIL AROUND 15Z. EXPECT THE LOW CLOUDS
AND FOG/IFR CIGS AND MVFR VSBYS WILL REACH LRD AREA BY 11Z
WITH LIFR VSBYS POSSIBLE IN NEAR DENSE FOG. VSBYS ARE
EXPECTED TO IMPROVE BY 15-16Z TO VFR WITH MVFR CIGS HOLDING
OVER VCT AREA THROUGH THE LATE MORNING BEFORE LIFTING.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 55 74 57 78 56 / 0 10 10 10 0
VICTORIA 50 71 54 75 57 / 0 10 10 10 10
LAREDO 54 82 55 83 53 / 0 0 0 0 0
ALICE 52 78 54 82 55 / 0 0 10 10 0
ROCKPORT 56 70 60 73 60 / 0 10 10 10 10
COTULLA 50 80 54 83 51 / 0 0 0 0 0
KINGSVILLE 52 77 54 78 56 / 0 0 0 10 10
NAVY CORPUS 56 71 60 73 59 / 0 10 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY FROM 2 AM TO 10 AM CST SATURDAY FOR THE
FOLLOWING ZONES: ARANSAS...BEE...CALHOUN...DUVAL...GOLIAD...
JIM WELLS...KLEBERG...LIVE OAK...MCMULLEN...NUECES...
REFUGIO...SAN PATRICIO...VICTORIA.
GM...NONE.
&&
$$
TMT/89...SHORT TERM
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1141 PM CST WED FEB 10 2016
.AVIATION...
VFR IS EXPECTED TO PREVAIL FOR THE 06Z TAFS. THE THOU/TIAH/KHGX
VAD WIND PROFILERS ARE ALL SHOWING SOUTHWESTERLY WINDS INCREASING
TO 35 TO 40 KNOTS AROUND 2000 FT AGL. HOUSTON IAH RAP FORECAST
WIND PROFILES SHOW THESE WINDS MAINTAINING THIS INTENSITY JUST OFF
THE SURFACE THROUGH 12Z AND THIS RAISES CONCERNS FOR AT LEAST
BRIEF LLWS CONDITIONS FOR THE HOUSTON TERMINALS. AMENDMENTS TO
INCLUDE LLWS MAY BE NEEDED IF SURFACE WINDS BECOME LIGHTER THAN
CURRENTLY ANTICIPATED.
OTHERWISE LIGHT SOUTHERLY/SOUTHWESTERLY WINDS OVERNIGHT WILL
INCREASE TO 10 TO 15 KNOTS DURING THE DAY ON THURSDAY... WITH
DAYTIME MIXING ALLOWING STRONGER GUSTS AROUND 20 TO POSSIBLY 25
KNOTS TO REACH THE SURFACE. AFTER 12/06Z... PATCHY RADIATION FOG
DEVELOPMENT MAY IMPACT THE TERMINALS WITH AT LEAST TEMPORARY
VISIBILITY/CEILING RESTRICTIONS POSSIBLE.
HUFFMAN
&&
.PREV DISCUSSION... /ISSUED 706 PM CST WED FEB 10 2016/
DISCUSSION...
CLEAR SKIES AND A COOL NIGHT AHEAD. SOUTHWEST WINDS WILL CONTINUE
MOST OF THE NIGHT ESPECIALLY ACROSS THE NORTHERN AND NORTHWESTERN
AREAS. TWEAKED THE MIN TEMPS DOWN A DEGREE IN THE EAST WHERE THE
AIR IS A LITTLE DRIER AND LIGHTER WINDS AND COOLER START TO THE
EVENING...VERY MINOR CHANGES.
MAY NEED TO DO AN UPDATE FOR SOME PATCHY SHALLOW FOG IN THE SW
AREAS AROUND EDNA/WHARTON/PALACIOS/WEST COLUMBIA. MODEL SOUNDINGS
SHOWING SOME VERY SHALLOW SATURATION OCCURRING BUT ATTM THINKING
JUST ENOUGH WIND MAY KEEP ANY FOG AT BAY.
45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 46 76 50 73 50 / 0 0 0 0 0
HOUSTON (IAH) 47 76 53 76 53 / 0 0 0 0 0
GALVESTON (GLS) 53 70 57 71 56 / 0 0 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 6 AM CST THURSDAY FOR
THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA
SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...45
AVIATION/MARINE...14
AREA FORECAST DISCUSSION
NWS PORTLAND OR
342 AM PST THU FEB 11 2016
.SYNOPSIS...SOUTHWEST WASHINGTON AND NORTHWEST OREGON REMAIN IN THE
SOUTHWEST FLOW ALOFT BETWEEN AN UPPER RIDGE INLAND OVER EASTERN
WASHINGTON AND OREGON AND A LOW PRESSURE SYSTEM OUT NEAR 140W. A
WEAK WARM FRONTAL BOUNDARY WILL LIFT NORTH TODAY...FOLLOWED BY THE
ASSOCIATED COLD FRONT MOVING ONSHORE TONIGHT AND THROUGH THE
FORECAST AREA ON FRIDAY. SNOW LEVELS WILL DROP DOWN TO PASS
ELEVATIONS FRIDAY NIGHT AS ANOTHER DISTURBANCE MOVES THROUGH FOR
SHOWERS. ANOTHER WARM FRONT WILL MOVE IN LATE SATURDAY AND SATURDAY
NIGHT FOR MORE RAIN AND FOR SOME SNOW IN THE MOUNTAINS...THEN LINGER
THROUGH SUNDAY AND PRODUCE MORE RAIN WHILE SNOW LEVELS RISE IN THE
CASCADES. THE WARM FRONT WILL MOVE MOSTLY NORTH OF THE AREA SUNDAY
NIGHT AND MONDAY. ANOTHER COLD FRONT WILL BRING SOME RAIN EARLY NEXT
WEEK BEFORE THE MAIN COLDER UPPER TROUGH MOVES THROUGH MID TO LATE
NEXT WEEK WITH FALLING SNOW LEVELS IN THE MOUNTAINS.
&&
.SHORT TERM...A FRONTAL BOUNDARY FROM THE WEAK SYSTEM THAT MOVED
THROUGH WEDNESDAY REMAINED OVER SOUTHWEST WASHINGTON AND NORTHWEST
OREGON OVERNIGHT...AND IS FORECAST TO LIFT NORTH AS A WARM FRONT
TODAY AND EARLY TONIGHT. THIS WILL BRING SOME AREAS OF RAIN TO
SOUTHWEST WASHINGTON AND NORTHWEST OREGON AT TIMES TODAY INTO
TONIGHT...ESPECIALLY ALONG THE COAST AND IN THE NORTH INTERIOR AREAS.
ECHOES HAVE BEGUN PICKING UP OFF THE NORTH OREGON COAST ALREADY EARLY
THIS MORNING...AND THIS MAY BE THE MAIN BOUNDARY. PRECIPITATION WILL
MOVE NORTH INTO WESTERN WASHINGTON TODAY AND THIS EVENING...BUT WILL
PROBABLY LINGER FROM ABOUT PORTLAND NORTH INLAND.
THE ASSOCIATED COLD FRONT OUT AROUND 135W THIS MORNING IS FORECAST TO
APPROACH THE COAST TONIGHT AND MOVE THROUGH IN THE INLAND AREAS IN
THE MORNING AND EARLY AFTERNOON ON FRIDAY...AND SHOULD BE EAST OF THE
CASCADES BY 4 PM FRIDAY. SNOW LEVELS WILL BE WELL ABOVE THE CASCADE
PASSES FOR MOST OF THIS EVENT.
SNOW LEVELS FALL TO BELOW THE PASSES FRIDAY NIGHT BEHIND THE FRONT
AND AS A SHORT WAVE MOVES THROUGH THAT WILL PRODUCE A DECENT SHOT OF
SHOWERS FRIDAY NIGHT AN SATURDAY MORNING. SNOW AMOUNTS LOOK A LITTLE
BELOW ADVISORY AMOUNTS AT THIS POINT.
THIS IS FORECAST TO BE FOLLOWED BY A WARM FRONT THAT WILL APPROACH
THE COAST LATE SATURDAY AND BE OVER THE FORECAST AREA SATURDAY NIGHT
AND SUNDAY. THE MODELS SHOW TWO GOOD WAVES MOVING ALONG THE WARM
FRONT DURING THIS TIME FRAME...ONE SATURDAY NIGHT AND THE OTHER ON
SUNDAY. SNOW LEVELS IN THE CASCADES WILL START BELOW THE CASCADE
PASSES SATURDAY NIGHT BUT LIKELY RISE WELL ABOVE THE PASSES ON
SUNDAY. THE BEST CHANCE OF SEEING ADVISORY AMOUNTS WOULD BE SATURDAY
NIGHT BEFORE THE SNOW LEVEL RISES...ESPECIALLY IN THE NORTH
CASCADES. TOLLESON
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
SATURDAY NIGHT THROUGH WEDNESDAY...THE PROGRESSIVE WEATHER PATTERN
WILL PERSIST INTO NEXT WEEK. MODELS CONTINUE TO SHOW A FRONT MOVING
ACROSS THE PAC NW LATE SATURDAY/EARLY SUNDAY. HAVE INCREASED POPS
ACROSS MUCH OF THE REGION SATURDAY EVENING TO ACCOUNT FOR THE FASTER
TIMING OF THE ECMWF. NOT EXPECTING TO SEE A LOT OF CASCADE SNOW WITH
THIS FRONT AS SNOW LEVELS QUICKLY RISE ABOVE 7000 FT EARLY SUNDAY. WE
COULD SEE A BRIEF BREAK FROM THE RAIN MONDAY AS A TRANSIENT UPPER
LEVEL RIDGE MOVES ACROSS THE REGION...BUT WILL MAINTAIN CHANCE POPS
DUE TO SOME LINGERING INSTABILITY. A WEAK SHORTWAVE COULD BRING SOME
LIGHT SHOWERS TUESDAY. ANOTHER FRONT ARRIVES LATE TUESDAY AND SHOULD
BRING MORE RAIN AND CASCADE SNOW TO THE REGION...WITH SNOW LEVELS
LOWERING TO AROUND 3500 FT WEDNESDAY AFTERNOON. TEMPS LOOK TO REMAIN
SLIGHTLY ABOVE NORMAL THROUGH THE FORECAST...BUT WILL TREND COOLER
AFTER MONDAY. /64
&&
.AVIATION...VFR ACROSS THE BOARD AT THIS HOUR.WITH CLOUD COVER LIKELY
INHIBITING ANY POTENTIAL FOR WIDESPREAD FOG DEVELOPMENT. 00Z GFS20
TIME HEIGHTS ARE PROVING TO BE THE BEST CIG GUIDANCE OF THE AVAILABLE
OPTIONS DURING THE DRY WEATHER OVER THE LAST COUPLE DAYS. CIGS MAY
LOWER CLOSER TO 050 EARLY THIS MORNING BUT APPEAR TO GET STUCK THERE.
MODELS HAVE CONTINUED TO WEAKEN THE INCOMING FRONT AND LAMP GUIDANCE
CONTINUES TO TREND AWAY FROM IFR VSBY IMPACTS AT THE COASTAL TAF
SITES OF KAST AND KONP AND ARE KEEPING CONDS AS MVFR CIG/VSBY
IMPACTS. INLAND TAF TERMINALS DO NOT REACH MVFR FOR VERY LONG, IF AT
ALL DURING THE NEXT 24 HOURS.
KPDX AND APPROACHES...VFR CONDITIONS ARE THE MOST LIKELY SCENARIO
THROUGH THE NEXT 24 HOURS. CIGS LOWERING TO MVFR OF 025-030 UNDER
RAIN BANDS TODAY ARE POSSIBLE BUT ONLY GIVE ABOUT A 10-20 PCT CHANCE.
BROAD OFFSHORE FLOW WILL BRING EASTERLY OUTFLOW WINDS FROM THE GORGE
TODAY. /JBONK
&&
.MARINE...NO SIGNIFICANTLY LARGE CHANGES TO THE FORECAST. ENP IS
GENERALLY ON TRACK WITH THE INCOMING SWELL AS 10 FT COMBINED SEAS
REACHED BUOY 89 AS OF THE 0200 HOUR. STILL COULD EXTEND THE SCA FOR
SEAS OUT THROUGH SUNDAY AFTERNOON PER ENP GUIDANCE BUT PREFER TO KEEP
IT COVERED FOR THE PERIODS OF HIGHER CONFIDENCE AT THIS TIME.
CONFUSED SEAS WILL PREVAIL THROUGH THE BETTER PART OF THE EVENING
BEFORE A SINGULAR WESTERLY SWELL WILL DOMINATE.
DID LOWER WINDS FOR THIS FIRST WARM FRONTAL PERIOD AS THE SURFACE LOW
WILL PIVOT NORTH AND WELL OFFSHORE WITH THE ASSOCIATED SURFACE TROUGH
AND TIGHTEST PRESSURE GRADIENT MAINLY STAYING OVER THE OFFSHORE
WATERS. IT WILL STILL COVER A DECENT PORTION OF THE OUTER WATERS. ITS
SOMEWHAT QUESTIONABLE WHETHER THE INNER WATERS WILL GET MANY GUSTS
ABOVE 21 KT TODAY BUT DONT FEEL CONFIDENT ENOUGH TO PULL DOWN THE
ADVISORY.
NEXT EVENT ON THE HORIZON APPEARS TO BE A POTENTIAL GALE EVENT
SATURDAY NIGHT. MODELS HAVE COME INTO BETTER AGREEMENT THOUGH STILL
DIFFER IN THE DETAILS. DECIDED TO TAKE A 50/50 BLEND OF THE GFS AND
ECMWF WINDS FIELDS. THIS APPROACH YIELDED PEAK GUSTS 35-37 KTS
SATURDAY NIGHT. PREFER TO SEE CONTINUED CONSISTENCY GIVEN THE
WISHY-WASHY AND DECAYING STRENGTH NATURE OF THE MODELS OVER THE LAST
COUPLE EVENTS. AFTER THAT...SEE A COUPLE SHORTER SCA TYPE EVENTS FOR
NEXT WEEK. /JBONK
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 10 AM THIS MORNING TO
4 AM PST FRIDAY FOR WATERS FROM CAPE SHOALWATER WA TO CASCADE
HEAD OR FROM 10 TO 60 NM-WATERS FROM CASCADE HEAD TO
FLORENCE OR FROM 10 TO 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PST
SATURDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR WINDS FROM 4 PM THIS AFTERNOON TO
4 AM PST FRIDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA
TO CASCADE HEAD OR OUT 10 NM-COASTAL WATERS FROM CASCADE HEAD
TO FLORENCE OR OUT 10 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
9 AM PST THIS MORNING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 4 PM
THIS AFTERNOON TO 11 PM PST THIS EVENING.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
Area Forecast Discussion
National Weather Service Spokane WA
307 AM PST THU FEB 11 2016
.SYNOPSIS...
A warm front will move across the Inland Northwest today and
tonight spreading a chance of rain across much of the area with
snow levels at the highest mountain elevation except near the
north Cascades. This front will be followed by the passage of a
cold front on Friday which will bring another chance of
precipitation to much of the area as well as slightly lower snow
levels. Unsettled weather will continue through the weekend into
early next week with valley rain, high mountain snow and breezy
winds expected. Temperatures will be quite mild on Monday with
many locations seeing highs in the mid 50s to low 60s.
&&
.DISCUSSION...
Today and tonight...The weather during this period will generally
revolve around a developing warm front. As of 2am, the water vapor
looper was showing a broad swath of moisture oriented from NNE-SSW
right off the coast. Meanwhile the upper level ridge of high
pressure remains poised over the Inland NW. The ridge is expected
to amplify slightly over the area today and tonight, as height
falls continue develop off the coast. Despite the presence of the
ridge we should see the first chance of precipitation this week,
the question is how soon will it develop and what will most of it
fall as. Looking closely at the latest radar mosaics it appears
the front will come through in two swaths. The first was
responsible for the east-west band of light echoes extending along
the WA/OR border and moving slowly northeastward. This one will
likely weaken as it moves farther northward with weakening
isentropic ascent, especially over the eastern third of Washington
and north Idaho. If anything falls out of this band it will likely
be very light. Over central Washington, the chances for measurable
precipitation are a little better due to slightly deeper moisture
combined with weak upslope flow into the Cascades. We suspect most
of the precipitation will fall as rain, however north of Lake
Chelan current wet-bulb temperatures are below freezing and they
may not climb much this morning. So we expect to see primarily
snow. The second surge of precipitation will bring a much better
chance of measurable precipitation. This wave is likely a
reflection of a compact shortwave located over northern California
moving steadily northward. The HRRR suggests this second band will
track into the Wenatchee and Moses Lake area around midday and
then into NE Washington and north Idaho by late afternoon or early
evening. Snow levels climb steadily with this portion of the warm
front. Wet-bulb zero heights reach 6000 feet or higher across the
entire forecast area save a small portion of the north Cascades
mainly impacting the Methow Valley. It`s a tough call as to how
effective the cold air damming will be in this area as the
surrounding air mass is awfully warm. The 850 mb flow maintains a
weak upslope orientation at least through early Friday which is
favorable for keeping snow levels locally down to the valley
floor, however surface temperature per bufkit profiles hover near
or slightly above freezing. We put several inches of snow in the
forecast across the upper Methow Valley however that`s assuming
any snow which falls is able to accumulate rather than melting as
it falls. Confidence is not high due to the precarious temperature
profiles. Elsewhere we are much more confident about primarily a
rain event. Rainfall totals should range from .15-35 inches across
the northern mountains and extending into the northern Idaho
Panhandle, with lighter amounts across southern Washington and the
central Panhandle. Near the Cascades, precipitation amounts could
range from 0.30-0.70 inches.
For Friday, the ridge finally gives way and a sw-ne oriented upper
level jet pokes into the southern portions of the region by
midday. This will turn the steady warm frontal precipitation to
more of a showery regime with most of the precipitation occurring
near the cold front. The cold front will likely end the
precipitation threat in the lee of the Cascades during the morning
hours as the upslope flow turns to a downslope westerly regime.
Meanwhile we expect the shower coverage to increase over the
eastern third of Washington and over the Panhandle during the
afternoon as the front destabilizes the atmosphere and enhances
any orographic ascent. Generally speaking the precipitation
amounts from the cold front will be lighter than whats produced
from the warm front.
Temperatures will remain milder both days
over the eastern third of Washington and the Idaho Panhandle with
highs in the 40s to middle 50s. Cooler temperatures will remain a
fixture over central Washington today due to the cold air damming
with highs in the 30s to lower 40s. The cold front should enhance
mixing on Friday bringing an end to the inversions with highs
climbing into the upper 30s to middle 40s. fx
Friday night through Wednesday...A mild and unsettled weather
pattern is expected this weekend through at least the middle of
next week. Initially a slightly cooler air mass will move in
Friday night and Saturday as an upper trough passes through. Mid
level westerly flow will favor most of these showers for the
Cascade crest and Idaho Panhandle. Snow levels by Saturday
morning lower to 3000-4000 feet with snow showers expected over
the mountain passes. Then an atmospheric river of subtropical
moisture becomes aimed at the area Saturday night into Sunday.
This will bring more rain and snow with snow levels rapidly rising
from 2500-4000 feet initially early Sunday to 6000-7000 feet
Monday as a warm front passes through. The atmospheric river
begins to lift north Sunday night into Monday to near or just
north of the Canadian border by Monday afternoon. Strong mid
level westerly flow throughout this event will favor moderate to
heavy precipitation for the Cascade crest and in the mountains of
the Idaho Panhandle with added orographic lift...with mainly
light amounts over Central and Eastern Washington as a strong rain
shadow develops. Meanwhile Monday into Tuesday a surface low
tracking into southern BC will result in a strengthening south-
southwest winds which combined with the warmer air mass will lead
to increased snow melt for areas that have snow currently. 850mb
winds increasing to 30-45 kts will likely result in breezy to
windy conditions over the region...especially the Upper Columbia
Basin, Spokane area, and Palouse. JW
&&
.AVIATION...
06Z TAFS: Weak wave exiting the forecast area this evening but a
few lingering spotty showers remain. The ridge still remains in
place with abundant low level moisture and overnight and early
morning temperatures not too far from their dewpints...therfore
another repeat of MVFR/IFR low stratus ceilings and IFR/LIFR fog
remains in store overnight tonight and early Thursday Morning.
Another weak disturbance will bring more light precipitation to
the aviation area tomorrow. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 45 38 47 34 45 35 / 10 60 70 50 40 60
Coeur d`Alene 46 37 47 36 45 34 / 10 70 70 70 60 70
Pullman 51 40 52 38 47 36 / 20 30 40 60 40 70
Lewiston 55 44 57 41 54 40 / 10 20 30 50 30 60
Colville 40 34 41 33 43 35 / 10 80 80 50 50 60
Sandpoint 41 35 41 34 42 34 / 10 80 80 90 60 70
Kellogg 42 37 43 35 39 33 / 10 70 60 90 80 90
Moses Lake 46 38 49 34 52 38 / 20 50 40 30 10 40
Wenatchee 39 34 44 33 47 35 / 50 80 50 20 10 50
Omak 38 35 37 30 42 33 / 30 90 70 30 20 40
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Air Stagnation Advisory until 10 AM PST Saturday for East Slopes
Northern Cascades-Moses Lake Area-Northeast Mountains-
Okanogan Highlands-Okanogan Valley-Upper Columbia Basin-
Waterville Plateau-Wenatchee Area.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS LOS ANGELES/OXNARD CA
1022 PM PST FRI FEB 12 2016
.SYNOPSIS...
A WEAK UPPER LEVEL TROUGH PASSING TO THE NORTH WILL PROVIDE A BRIEF
BREAK FROM THE RECORD HEAT THIS WEEKEND. A BUILDING RIDGE ALOFT
AND GUSTY OFFSHORE WINDS BRING A RETURN OF RECORD HEAT EARLY NEXT
WEEK. A SECOND UPPER LEVEL LOW WILL SUPPORT MUCH COOLER CONDITIONS
WITH THE CHANCE OF RAIN LATE WEDNESDAY INTO THURSDAY.
&&
.SHORT TERM...(FRI-MON)
UPPER LEVEL TROUGH MOVING INTO NORTHERN CALIFORNIA TONIGHT WITH
RIDGE AXIS SLIDING WELL EAST OF OUR AREA. THIS HAS RESULTED IN
SLIGHT ONSHORE TRENDS THIS EVENING...WITH CURRENT LAX-DAGGETT
GRADIENT AT -1.9 MB. SATELLITE IMAGERY SHOWING AREAS OF LOW
CLOUDS AND DENSE FOG ACROSS PORTIONS OF THE COASTAL WATERS
(WHICH WAS HIGHLIGHTED WITH A MARINE WEATHER STATEMENT)...LOCALLY
EXTENDING INTO THE CENTRAL COAST THIS EVENING. MOST OF THE FOG
OFFSHORE OF LOS ANGELES COUNTY IS FORMING NEAR CATALINA ISLAND
AND THE SAN PEDRO CHANNEL. BUT CONDITIONS ARE COMING TOGETHER FOR
SOME PATCHY DENSE FOG JUST ABOUT ANYWHERE ALONG THE IMMEDIATE
COAST TONIGHT...AND HAVE INCLUDED THAT IN ZONE UPDATE. COMBINATION
OF SHALLOW/STRONG MARINE INVERSION...WEAKENING PRESSURE
GRADIENTS...AND COASTAL DEWPOINTS RISING INTO THE MID 50S IS
REASONING FOR POTENTIAL DENSE FOG ALONG IMMEDIATE COAST.
AS THE TROUGH MOVES INLAND ON SATURDAY...THERE IS SOME INCREASING
NORTHERLY FLOW SETTING UP ACROSS THE FORECAST AREA...ESPECIALLY
TOMORROW NIGHT. INLAND AREAS NOT SHOWING A WHOLE LOT OF COOLING
ON SATURDAY AT 950 MB LEVEL...SO BUMPED UP MOST VALLEY
TEMPERATURES A FEW DEGREES IN EVENING UPDATE. TAKING A GLANCE
AT THE 00Z NAM MODEL...SEEING ANOTHER RESURGENCE OF OFFSHORE
FLOW FROM SUNDAY THROUGH TUESDAY WITH UPPER LEVEL RIDGE REBUILDING
OVER THE AREA. STILL LOOKING LIKE STRONGEST OFFSHORE WIND PUSH
WILL BE SUNDAY NIGHT INTO MONDAY WITH WIDESPREAD ADVISORIES
LIKELY ACROSS VENTURA AND LOS ANGELES COUNTIES. WITH PROJECTED
LAX-DAGGETT GRADIENT APPROACHING -7 MB ON SUNDAY MORNING AND
SOME UPPER LEVEL WIND/THERMAL SUPPORT...COULD SEE SOME ISOLATED
WIND GUSTS UP TO 60 MPH IN THE FAVORED MOUNTAIN AREAS. THE
OFFSHORE WINDS WITH LOW HUMIDITIES AND WARM TEMPERATURES WILL
BRING ANOTHER ROUND OF ELEVATED FIRE DANGER SUNDAY THROUGH
TUESDAY. THE OTHER BIG STORY WILL CONTINUE TO BE THE UNUSUALLY
HOT TEMPERATURES EXPECTED SUNDAY THROUGH TUESDAY...WITH MANY
COASTAL/VALLEY AREAS EXPECTED TO CLIMB WELL INTO THE 80S AND LOWER
90S. ON SUNDAY...COULD SEE A COUPLE OF RECORDS BROKEN THEN
EVEN BETTER CHANCE OF RECORDS BEING SET ON MONDAY AND TUESDAY.
.LONG TERM...(TUE-FRI)
FOR THE EXTENDED...12Z MODELS START OUT IN DECENT SYNOPTIC
AGREEMENT...BUT DIVERGE LATER IN THE PERIOD. AT UPPER LEVELS
RIDGE WILL LINGER ON TUESDAY THEN A TROUGH WILL APPROACH AND MOVES
ACROSS THE WEST COAST WEDNESDAY THROUGH FRIDAY. NEAR THE SURFACE
WEAK OFFSHORE FLOW WILL PREVAIL ON TUESDAY THEN SHIFT TO ONSHORE
WEDNESDAY THROUGH FRIDAY.
FORECAST-WISE...TUESDAY WILL BE AN UNREMARKABLE DAY WITH CLEAR
SKIES...LIGHT OFFSHORE BREEZES AND HIGH TEMPERATURES WELL ABOVE
NORMAL. FOR WEDNESDAY AND THURSDAY...THE MODELS DIVERGE NOTICEABLY
LEADING TO A LOW CONFIDENCE FORECAST. THE ECMWF MOVES A TROUGH
ACROSS THE AREA WEDNESDAY/THURSDAY AND GENERATES A DECENT RAIN
EVENT FOR THE AREA. CONVERSELY...THE GFS IS MUCH LESS BULLISH WITH
THIS TROUGH...HARDLY SPITTING OUT ANY PRECIPITATION. WITH SUCH
MODELS DIFFERENCES...WILL NOT DEVIATE FROM PREVIOUS FORECAST
THINKING WHICH INCLUDED CHANCE/SLIGHT CHANCE POPS FOR THE AREA
WEDNESDAY AND THURSDAY. HOPEFULLY...MODELS WILL COME INTO SOME
BETTER AGREEMENT OVER THE NEXT COUPLE OF DAYS. BY THURSDAY NIGHT
AND FRIDAY...BOTH MODELS PUSH TROUGH EAST OF THE AREA AND INDICATE
DRY CONDITIONS.
&&
.AVIATION...13/0600Z.
AT 0530Z...AT KLAX...THERE WAS A SURFACE BASED INVERSION LAYER TO
1700 FEET WITH A TEMP OF 24 DEG C.
FOR COASTAL TAF SITES INCLUDING KSMX & KPRB...LOW CONFIDENCE IN
THE 06Z TAFS THROUGH 16Z DUE THE POSSIBILITY OF FOG/LOW CLOUDS.
EXPECT IFR TO LIFR WITH LOCALIZED VLIFR IN AREAS WHERE FOG/LOW
CLOUDS DO DEVELOP. MODERATE TO HIGH CONFIDENCE FOR THE REMAINDER
OF THE TAF PERIOD.
INLAND TAF SITES...HIGH CONFIDENCE IN 06Z CAVU TAFS.
KLAX...LOW CONFIDENCE IN 06Z TAF THROUGH 16Z DUE TO THE
POSSIBILITY OF LOW FOG AND LOW CLOUDS. THERE IS A 40 PERCENT
CHANCE OF LIFR TO VLIFR CIGS/VSBYS DUE TO FOG/LOW CLOUDS THROUGH
16Z. MODERATE CONFIDENCE IN THE REMAINDER OF THE TAF PERIOD.
KBUR...HIGH CONFIDENCE IN 06Z CAVU TAF.
&&
.MARINE...12/800 PM...
A MARINE WEATHER STATEMENT WAS ISSUED THIS EVENING FOR THE
POSSIBILITY OF DENSE FOG FOR ALL AREAS THROUGH SATURDAY MORNING.
PLEASE SEE MWSLOX FOR DETAILS.
FOR THE OUTER WATERS...THERE IS HIGH CONFIDENCE IN SMALL CRAFT
ADVISORY (SCA) CONDITIONS THROUGH LATE SUNDAY NIGHT DUE TO EITHER
SCA WINDS OR A 10-13 FT...LONG PERIOD W-NW SWELL. THE STRONGEST
N-NW WINDS ACROSS THE OUTER WATERS ARE EXPECTED SATURDAY AFTERNOON
AND NIGHT...WHEN THERE COULD BE SOME LOCAL GALE FORCE WINDS. SCA
WINDS COULD LINGER INTO MONDAY...BUT SHOULD WEAKEN CONSIDERABLY BY
TUESDAY.
FOR THE INNER WATERS N OF PT CONCEPTION...THERE IS HIGH
CONFIDENCE IN SCA CONDITIONS FOR HAZARDOUS SEAS THROUGH SUNDAY
EVENING. THIS IS DUE TO THE 10-13 FT...LONG PERIOD W-NW SWELL.
WINDS WILL GENERALLY REMAIN BELOW SCA CRITERIA...THROUGH THE
FORECAST PERIOD...BUT THERE COULD BE SOME LOCAL N-NE GUSTS TO 25
KT SATURDAY EVENING THROUGH MONDAY EVENING.
FOR THE INNER WATERS S OF PT CONCEPTION...THERE IS GOOD CONFIDENCE
THAT WINDS AND SEAS WILL REMAIN BELOW SCA CRITERIA THROUGH SUNDAY
AFTERNOON. HOWEVER...SOME 10 FT SEAS ARE POSSIBLE IN WESTERN
PORTIONS OF THE SANTA BARBARA CHANNEL THROUGH SATURDAY
AFTERNOON...DUE TO THE LONG PERIOD SWELL. THERE IS ALSO A CHANCE
FOR SOME ISOLATED NE WIND GUSTS TO 25 KT ON SUNDAY MORNING BETWEEN
SANTA MONICA AND VENTURA. STRONGER NE WINDS ARE EXPECTED LATE
SUNDAY NIGHT INTO MONDAY...WHEN A SCA MAY BE NEEDED.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...HIGH SURF ADVISORY IN EFFECT UNTIL 9 AM PST SUNDAY FOR ZONES
34-35. (SEE LAXCFWLOX).
BEACH HAZARDS STATEMENT IN EFFECT THROUGH SUNDAY MORNING FOR
ZONE 39. (SEE LAXCFWLOX).
HIGH SURF ADVISORY IN EFFECT UNTIL NOON PST SUNDAY FOR ZONES
40-41-87. (SEE LAXCFWLOX).
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS IN EFFECT UNTIL 9 PM
PST SUNDAY FOR ZONE 645. (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 AM PST MONDAY FOR
ZONES 670-673-676. (SEE LAXMWWLOX).
&&
$$
PUBLIC...GOMBERG
AVIATION...MUNROE/DB
MARINE...SUKUP
SYNOPSIS...MUNROE
WEATHER.GOV/LOSANGELES
[top]
Area Forecast Discussion
National Weather Service Sacramento CA
1015 PM PST FRI FEB 12 2016
.SYNOPSIS...
Dry and mild weather through early next week with well above
normal temperatures. Wetter and cooler weather pattern expected
middle to latter portion of next week.
&&
.DISCUSSION...
Upper trof moving through Norcal with weakening surface front. CI/CS
streaming into Interior NorCal is now sagging SEwd with upper trof.
Moisture profiles from BUFKIT show high cloudiness eroding/
dissipating around 12z at the TAF sites in the Srn Sac/Nrn SJV with
winds turning NW. This should limit/preclude widespread fog
production. Subjective analysis is the HRRR is likely hitting the )
VSBYS too hard in the Vly Sat morning...and believe the fog will not
be as dense or cover as much area as forecast. The patchy fog
wording currently in the zones should suffice. JHM
Heights and thicknesses progged to increase over the weekend as
upper ridge amplifies off the West Coast. High temperatures
forecast mainly in the lower 70s Saturday for the Central Valley,
which is upwards of 10 to 12 degrees above normal and at record
values for KSAC/KSCK. Some short lived patchy morning valley fog
will continue to be possible over the weekend from Sacramento
southward.
Another weak weather system rides over the ridge Sunday with some
light overrunning precip possible into far northern portions of
CA. However associated precip continues to be modeled north of
our forecast area. Surface high pressure building through Oregon
into the Great Basin will result in some locally breezy northerly
wind from Sunday afternoon into Monday. High temps expected to
slowly trend up over the weekend into Monday. Max Ts in the
Central Valley expected in the mid to upper 70s Sun/Mon with
readings continuing right around record values for the Sacramento
and Stockton areas.
PCH
.EXTENDED DISCUSSION (Tuesday THROUGH Friday)
Conditions will remain dry through Tuesday. On Wednesday, NorCal
transitions into a wet pattern as a trough impacts the west coast.
Both the GFS & ECMWF models agree that this storm will start
impacting our region by Wednesday evening. However, the challenge
with this system is that the models disagree on the details. The
GFS shows a quickly moving trough that weakens by Thursday
morning and puts our region back into a dry, ridging pattern by
Thursday afternoon/evening. The ECMWF indicates a stronger,
wetter trough that keeps a threat of precipitation in our CWA
through Thursday evening. Have medium confidence that interior
NorCal will get light to moderate rain/snow Wednesday evening into
Thursday afternoon with snow levels around 5000 ft.
The models continue to diverge on Friday with the GFS maintaining
a dry ridge while the ECMWF brings in another wave of
precipitation that impacts area north of Interstate 80. Confidence
is lower, but have kept lingering chances of precipitation
through Friday until models come into better agreement.
JBB
&&
.AVIATION...
SWly flow alf vrg to NWly Sat. Vrbl clds AOA FL120 for Intr NorCal
nxt 24 hrs with VFR conds exc isold MVFR/IFR/LIFR poss in Srn
Sac/Nrn San Joaquin vlys in BR/FG btwn 10z-18z Sat.
&&
.STO Watches/Warnings/Advisories...
None.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBANY NY
1235 AM EST SAT FEB 13 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL SWEEP ACROSS THE REGION OVERNIGHT WITH
ISOLATED TO SCATTERED SNOW SHOWERS AHEAD OF IT. BEHIND THE ARCTIC
COLD FRONT...THE COLDEST AIRMASS OF THE SEASON WILL BUILD ACROSS
THE REGION FOR THE WEEKEND WITH BITTERLY COLD TEMPERATURES AND
WIND CHILLS. A STORM SYSTEM MAY IMPACT THE REGION MONDAY INTO THE
MID WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1235 AM EST...AN ARCTIC COLD FRONT WAS POSITIONED JUST
NORTH AND WEST OF THE FORECAST AREA AND POISED TO MOVE SOUTHWARD
THROUGH THE OVERNIGHT HOURS. THE FRONT WILL BE MOVING THROUGH THE
REGION BETWEEN 1 AM AND 6 AM FROM NW TO SE. AHEAD OF THIS FRONTAL
BOUNDARY THERE WILL BE ISOLATED TO SCATTERED SNOW
SHOWERS...ALTHOUGH THE INTENSITY AND COVERAGE OF SNOW SHOWERS HAS
DECREASED OVER THE PAST FEW HOURS REMOVED FROM THE MOISTURE SOURCE
/LAKE ONTARIO/. THE LATEST 3-KM HRRR SHOWS SNOW SHOWERS WEAKENING
AS THEY TRACK SOUTHEASTWARD THROUGH THE AREA ASSOCIATED WITH THE
BOUNDARY. SNOWFALL AMOUNTS ARE EXPECTED TO BE ON THE LIGHT SIDE
WITH GENERALLY A DUSTING TO 2 INCHES. THE HIGHER TOTALS WILL BE
OVER THE WRN DACKS.
IT WILL BE ANOTHER VERY COLD NIGHT...BUT NOT AS COLD AS
TEMPERATURES WILL BE LATER IN THE WEEKEND. LOWS OVERNIGHT WILL
RANGE FROM 10 BELOW ZERO NORTHWEST AREAS TO 15 ABOVE ZERO
SOUTHEAST TOWARDS NW CT AND THE MID HUDSON RIVER VALLEY. WINDS
WILL ALSO INCREASE OVERNIGHT ACROSS THE FCST AREA WITH A WIND
CHILL WARNING STARTING AT 3 AM FOR THE SOUTHERN
ADIRONDACKS...WESTERN MOHAWK VALLEY...EASTERN CATSKILLS AND
SOUTHERN VERMONT. THE JAIL BREAK OF ARCTIC AIR KICKS IN...AS THE
WINDS BEHIND THE FRONT WILL BE MAINLY WEST TO SOUTHWEST AT 10 TO
20 MPH WITH GUSTS TO 30-40 MPH.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
WIND CHILL WARNINGS IN EFFECT FOR SATURDAY-SUNDAY MORNING FOR ALL
OF EASTERN NEW YORK AND ADJACENT WESTERN NEW ENGLAND.
THE COLDEST AIRMASS OF THE SEASON WILL BE WITH US OVER THE WEEKEND
IN THE WAKE OF THE ARCTIC FRONT AS AN ARCTIC AREA OF HIGH PRESSURE
SETTLES OVER THE REGION BY SUNDAY. H8 TEMPS DROP TO 27 TO 34
DEGREES BELOW ZERO BY SATURDAY EVENING. HAVE GONE WITH A NON-
DIURNAL RANGE OF TEMPS ON SATURDAY AS THE LOWS FRIDAY NIGHT AND
THE HIGHS ON SATURDAY SHOULD BE THE SAME WITH THE TEMPS DROPPING
ALL DAY ON SATURDAY. TEMPS ARE EXPECTED TO DROP FROM 10 BELOW TO
15 ABOVE ZERO EARLY SATURDAY MORNING TO 15 BELOW ZERO TO 5 ABOVE
ZERO BY EARLY SATURDAY EVENING. WIND CHILLS ON SATURDAY WILL RANGE
FROM 10 BELOW TO 35 BELOW ZERO WITH NORTHWEST WINDS 10 TO 20 MPH
WITH GUSTS 30 TO 40 MPH.
SATURDAY NIGHT WILL BE ESPECIALLY BRUTAL AS AIR TEMPERATURES ARE
EXPECTED TO DROP TO 5 BELOW TO NEAR 30 BELOW ZERO WITH WIND CHILL
VALUES 25 BELOW TO NEAR 50 BELOW ZERO.
SUNDAY INTO SUNDAY NIGHT...HIGH PRESSURE WILL MOVE OVER OUR REGION
ON SUNDAY AND OFF THE EASTERN SEABOARD LATE SUNDAY NIGHT. WINDS
WILL STILL BE FAIRLY STRONG ON SUNDAY MORNING BEFORE SUBSIDING
LATER SUNDAY INTO SUNDAY NIGHT. HIGHS ON SUNDAY WILL BE IN THE
ZERO TO 15 ABOVE ZERO RANGE WITH THE LOWS SUNDAY NIGHT BETWEEN 10
BELOW AND 5 ABOVE ZERO.
MONDAY WILL FEATURE INCREASING CLOUDS AS THE NEXT SYSTEM STARTS TO
TRACK NORTHEASTWARD FROM THE SOUTHEAST COAST. HIGHS WILL MODERATE
ON MONDAY RANGING FROM THE UPPER TEENS NORTHWEST TO UPPER 20S
SOUTHEAST WITH A CHANCE OF SNOW ACROSS THE SOUTHERN HALF OF THE FA
LATE IN THE DAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A SIGNIFICANT STORM IS EXPECTED TO IMPACT THE REGION DURING THE
EARLY PART OF THE EXTENDED PERIOD. THERE IS INCREASING CONFIDENCE
AS TO THE TRACK AND INTENSITY OF THIS SYSTEM... AT LEAST IN ITS
EARLY STAGES. TWO TO SIX INCH ACCUMULATIONS ARE EXPECTED MONDAY
NIGHT... WHICH IS MORE OR LESS THE START OF THE EVENT. BEYOND THAT
THERE IS STILL UNCERTAINTY AS TO PRECIPITATION TYPE AS THERE IS
PLENTY OF MILD AIR TO BE DRAWN IN OUT AHEAD OF THIS SYSTEM...THUS
THE EXACT TRACK AND INTENSITY WILL BE CRUCIAL. RIGHT NOW...THE
TRACK IS EXPECTED TO BE FROM ABOUT CHARLOTTE NORTH CAROLINA
THROUGH ALBANY.
BECAUSE THE TRACK IS NOT SEEN AS GOING FAR ENOUGH TO THE EAST TO
GIVE US AN ALL SNOW EVENT...INDICATIONS ARE PRECIPITATION WILL
LIKELY CHANGE OVER TO RAIN FOR A TIME ON TUESDAY...PARTICULARLY
OUTSIDE OF THE ADIRONDACKS...BEFORE EVERYTHING TAPERS OFF AS SNOW
TUESDAY NIGHT. THERE IS THE POTENTIAL FOR VERY SIGNIFICANT
ACCUMULATIONS...BUT ANY DECENT PERIOD OF RAIN...AS IS EXPECTED RIGHT
NOW...WILL KEEP SNOW ACCUMULATIONS AT BAY.
BROAD LAKE ENHANCEMENT ON INCREASING WESTERLY WINDS BEHIND THE
DEPARTING STORM WILL KEEP SNOW SHOWERS OF LIGHT AMOUNTS GOING FOR
MANY AREAS TUESDAY NIGHT...WITH MIXED RAIN AND SNOW SHOWERS FOR
WEDNESDAY. BUT THE ACTIVITY WILL WIND DOWN RAPIDLY ON THURSDAY AS
HIGH PRESSURE SETTLES IN...BUT WITHOUT THE EXTREME COLD WE/RE
EXPECTING THIS WEEKEND.
HIGH TEMPERATURES ARE EXPECTED TO RANGE FROM THE MID 30S THROUGH THE
UPPER 40S ON TUESDAY...THE UPPER 20S TO AROUND 40 DEGREES ON
WEDNESDAY...AND THE MID TEENS TO AROUND 30 DEGREES ON THURSDAY.
FRIDAY HIGHS WILL REBOUND SOMEWHAT. OVERNIGHT LOWS MONDAY NIGHT
WILL RANGE FROM THE UPPER TEENS IN THE MOUNTAINS TO THE UPPER 20S IN
THE LOWER MID HUDSON VALLEY. TUESDAY NIGHT...THEY WILL RANGE FROM
THE MID 20S IN THE WESTERN ADIRONDACKS...TO THE LOWER 30S DOWN THE
HUDSON VALLEY. WEDNESDAY NIGHT WILL TURN SHARPLY COLDER...AND
THURSDAY NIGHT WILL BE COLDEST...WITH LOWS RANGING FROM THE LOW
SINGLE DIGITS IN THE WESTERN ADIRONDACKS...TO THE UPPER TEENS DOWN
THE MID HUDSON VALLEY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
A CLIPPER LOW WILL PASS NORTH OF THE REGION THROUGH THE EARLY
MORNING HOURS...AS THE ASSOCIATED ARCTIC COLD FRONT TRACKS THROUGH.
A NW FLOW OF ARCTIC AIR WILL IMPACT THE REGION THROUGH THE DAY INTO
THE NIGHT PERIOD WITH GUSTY WINDS.
THE ARCTIC FRONT WILL FOCUS SOME ISOLATED TO SCATTERED SNOW SHOWERS
OR A SQUALL FROM THE CAPITAL REGION NORTH...IMPACTING KGFL/KALB/KPSF
BETWEEN 04Z-09Z. THE SNOW SHOWERS WILL BE FAIRLY ISOLATED TO
SCATTERED IN COVERAGE DUE TO VERY LIMITED LOW-LEVEL MOISTURE. A VCSH
WAS USED AT KALB/KPSF/KGFL THROUGH ABOUT 10-11Z.
VFR CONDITIONS WILL BE DOMINATE...ASIDE FOR SOME MVFR CIGS/VSBYS
WITH ANY SNOW SHOWERS/ISOLD SQUALLS ESPECIALLY AT KPSF/KGFL. CIGS
WILL BE MAINLY IN THE 4-9 KFT AGL RANGE. IN THE WAKE OF THE FRONT
AFTER DAYBREAK...SOME LINGERING STRATOCUMULUS OR MID LEVEL CLOUDS
WILL LINGER. OVERALL...VFR CONDITIONS WILL CONTINUE IN THE FRIGID
NORTHWEST FLOW THROUGH THE PM.
THE WINDS WILL BE FROM THE SOUTH TO SOUTHWEST AT 4-10 KTS PRIOR TO
THE FRONTAL PASSAGE BEFORE DAYBREAK...THEN VEER TO THE W TO NW AT 6-
12 KTS WITH SOME GUSTS TO 20-25 KTS. THE WINDS WILL INCREASE IN THE
WAKE OF THE ARCTIC FRONT LATE IN THE MORNING INTO THE AFTERNOON AT
12-20 KTS WITH SOME GUSTS AROUND 30 KTS...ESPECIALLY AT KALB/KPSF.
WINDS WILL SLOWLY DIMINISH DURING THE EVENING BUT WILL STILL BE
GUSTY.
THE WINDS WILL BE FROM THE SOUTH TO SOUTHWEST AT 4-10 KTS PRIOR TO
MIDNIGHT...THEN VEER TO THE W TO NW AT 6-12 KTS BEFORE DAYBREAK
WITH SOME GUSTS TO 20-25 KTS. THE WINDS WILL INCREASE IN THE WAKE
OF THE ARCTIC FRONT LATE TOMORROW MORNING INTO THE AFTERNOON AT
12-20 KTS WITH SOME GUSTS AROUND 30 KTS...ESPECIALLY AT KALB/KPSF.
OUTLOOK...
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
SUNDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE SN.
WASHINGTONS BIRTHDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...SN.
MONDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA...SN.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
WITH BITTER COLD AIR IN PLACE...ICE COVERAGE ON RIVERS AND LAKES
WILL CONTINUE TO INCREASE AND STRENGTHEN OVER THE NEXT FEW DAYS. A
FEW LIGHT SNOW SHOWERS ARE POSSIBLE...MAINLY THIS EVENING...BUT THIS
WILL AMOUNT TO LITTLE IF ANY HYDROLOGIC SIGNIFICANCE.
HOWEVER...THERE IS THE POTENTIAL FOR A HEAVY PRECIPITATION EVENT TO
IMPACT THE REGION FROM MONDAY NIGHT THROUGH WEDNESDAY. THERE
REMAINS CONSIDERABLE UNCERTAINTY REGARDING THE TYPES OF
PRECIPITATION THAT MAY OCCUR...WHICH WILL ULTIMATELY DEPEND ON THE
EXACT TRACK OF THIS POTENTIAL STORM SYSTEM. AT THIS TIME...MODEL
GUIDANCE IS SUGGESTING ONE TO THREE INCHES OF LIQUID EQUIVALENT
COULD OCCUR...AND MUCH OF THIS COULD BE IN THE FORM OF RAIN. IF
THIS RAIN WERE TO MATERIALIZE...IT COULD HAVE A HIGH IMPACT ON
RIVERS AND STREAMS...ESP CONSIDERING THE GROUND WILL BE FULLY
FROZEN BY THAT TIME...ALLOWING MUCH OF THE PRECIP TO BE RUNOFF.
DETAILS WILL BECOME MORE CERTAIN OVER THE NEXT FEW DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WIND CHILL WARNING FROM 1 PM THIS AFTERNOON TO 1 PM EST SUNDAY
FOR CTZ001-013.
NY...WIND CHILL WARNING UNTIL 1 PM EST SUNDAY FOR NYZ032-033-038-
042-047-051-058-063-082.
WIND CHILL WARNING FROM 1 PM THIS AFTERNOON TO 1 PM EST SUNDAY
FOR NYZ039>041-043-048>050-052>054-059>061-064>066-083-
084.
MA...WIND CHILL WARNING FROM 1 PM THIS AFTERNOON TO 1 PM EST SUNDAY
FOR MAZ001-025.
VT...WIND CHILL WARNING UNTIL 1 PM EST SUNDAY FOR VTZ013>015.
&&
$$
SYNOPSIS...IRL/WASULA
NEAR TERM...11/JPV/WASULA
SHORT TERM...11
LONG TERM...ELH
AVIATION...NAS
HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
349 AM EST SAT FEB 13 2016
.DISCUSSION...
...POOR TO HAZARDOUS BOATING CONDITIONS THIS WEEKEND...
TODAY-TONIGHT...
LATEST ANALYSIS SHOWS A DRY COLD FRONT PUSHING INTO THE PANHANDLE...
A LITTLE SLOWER THAN ANTICIPATED. THE 00Z KJAX/KTAE RAOBS INDICATE
PWATS ONLY ARND 0.75"...WHILE LATEST SAT PICS SHOW A FEW CLOUD BANDS
DVLPG AHEAD OF THE FRONT IN TANDEM WITH A BAND OF H100-H85 DEWPOINT
DEPRESSIONS BTWN 3-5C OVER THE NRN PENINSULA. AHEAD OF THE FRONT...
HOWEVER...A DRY/STABLE AIRMASS REMAINS IN PLACE. THE 00Z RAOBS AT
KXMR/KTBW/KMFL MEASURED PWAT VALUES ARND 0.50"...WHILE RAP ANALYSIS
INDICATES H100-H85 DEWPOINT DEPRESSIONS BTWN 5-7C ALONG THE I-4
CORRIDOR...ARND 15C OVER LAKE OKEECHOBEE AND THE TREASURE COAST.
AS EXPECTED...THE APPROACHING FRONTAL TROF HAS ERODED THE H100-H70
RIDGE/ANTICYCLONE AXIS THAT WAS IN PLACE OVER THE FL PENINSULA ON
FRI. THE RIDGE HAS EFFECTIVELY SPLIT IN TWO WITH THE WRN HALF
RETROGRADING INTO THE WRN GOMEX...THE ERN HALF PUSHING WELL E OF THE
BAHAMA BANK TO MERGE WITH THE ATLC SUBTROPICAL RIDGE. THIS WILL
LEAVE THE FRONT WITH LITTLE IMPEDANCE TO SLOW ITS FORWARD MOTION...
ESPECIALLY GIVEN THE RAP40 INDICATES AVG H100-H70 FLOW BEHIND IT IS
NW AT 25-30KTS.
ANOTHER QUIET WX DAY IN STORE AS FRONTAL MOISTURE IS SIMPLY TOO LOW
TO SUPPORT THE FORMATION OF ANYTHING MORE THAN A LOW LVL CLOUD
DECK...MEAN RH VALUES THRU THE H100-H85 LYR ARE AOB 80PCT.
FURTHERMORE...RAOBS SHOW A LINGERING SUBSIDENCE INVERSION IN THE
H90-H80 LYR THAT WILL PANCAKE ANY CLOUD DECK BLO 5KFT.
TEMPS WILL BE A BIT ON THE COOL SIDE FROM BREVARD/OSCEOLA CO NWD
ONCE THE FRONT PUSHES THRU AS NWRLY FLOW DVLPS...KEEPING AFTN
READINGS IN THE L/M60S DESPITE NEAR FULL SUN. TREASURE COAST/LAKE
OKEECHOBEE AREAS WELL HAVE TIME TO WARM INTO THE L70S BEFORE THE
FROPA...BUT EVEN THESE WILL BE 3-5F BLO AVG. TIGHTENING PGRAD BEHIND
THE FRONT WILL ALLOW NRLY WINDS TO PERSIST OVERNIGHT...RESULTING IN
A COOL AIR ADVECTION PATTERN THAT WILL ALLOW MIN TEMPS TO FALL INTO
THE L/M40S W OF I-95. MARINE INFLUENCE WILL KEEP COASTAL TEMPS A FEW
DEGS WARMER...GENERALLY U40S/L50S.
SUNDAY...
A HIGH PRESSURE RIDGE ALONG THE EASTERN SEABOARD WILL SHIFT
OFFSHORE. AN EARLY MORNING COASTAL TROUGH WILL EXIST THEN
DISSIPATE...GIVING WAY TO AN EASTERLY WIND FLOW IN THE AFTERNOON.
THE AIR MASS WILL INITIALLY BE VERY DRY SO COASTAL RAIN CHANCES
LOOK TO BE 10-15 PERCENT. WILL LEAVE SMALL POPS ALONG THE IMMEDIATE
COAST THROUGH SUNDAY NIGHT. FORECAST SOUNDINGS ARE STILL SUPPORTIVE
OF STRATOCUMULUS SPREADING INLAND FROM THE ATLANTIC. SO DESPITE
THE MORE MILD EAST WIND FLOW...THIS CLOUDINESS SHOULD KEEP DAYTIME
HIGHS A LITTLE BELOW THOSE FROM TODAY...MAINLY MID 60S NORTH AND
UPPER 60S SOUTH. ONSHORE LOW LEVEL WINDS WILL KEEP OVERNIGHT LOWS
MORE MILD...LOWER 50S NORTH INTERIOR AND UPPER 50S SOUTH COAST.
MON INTO EARLY TUE...
THIS PERIOD IS THE MAIN ITEM OF INTEREST FOR THE UPCOMING WEEK. A
SHORTWAVE TROUGH IS FORECAST TO MOVE ACROSS THE SOUTHERN STATES
AND SPIN UP A SURFACE LOW. THE 00Z GFS SHOWS A WEAKER SYSTEM FARTHER
NORTH THAN 24 HOURS AGO. HENCE THE LOCAL LOW LEVEL WIND FIELDS ARE
FORECAST TO BE WEAKER. PRECIPITABLE WATER IS STILL SHOWN TO ONLY
RECOVER TO ABOUT 1.3 INCHES WITH SURFACE DEW POINTS IN THE UPPER
50S TO LOWER 60S. MOS POPS HAVE BACKED OFF TO 30-40 PERCENT FOR
MON NIGHT. THE ECMWF ALSO SHOWS A WEAKER SYSTEM BUT THE POP VALUES
ARE A LOT HIGHER THAN THE GFS.
DO NOT WANT TO MAKE SIGNIFICANT CHANGES TO THE FORECAST JUST YET
AS THE SUBTROPICAL JET CORE WILL BE NEARBY AND TEMPS ALOFT WILL
BE QUITE COLD...SO EXPECT THAT THERE COULD BE ENOUGH SUPPORT FOR
CONVECTION OVER THE GULF OF MEXICO TO SPREAD WELL INLAND. HAVE
TRIMMED POPS BACK TO 50 PERCENT FOR MON NIGHT BUT KEPT SLIGHT
CHANCE FOR THUNDER. RECENT WEAKER MODEL SOLUTIONS FOR THIS SYSTEM
SUGGEST SOME SHOWER CHANCES MAY LINGER INTO TUE.
REST OF WEEK...
COLD FRONT IS FORECAST TO PUSH EAST OF THE AREA TUE OR TUE NIGHT...
BRINGING DRYING AND WEAK COLD AIR ADVECTION. A SURFACE HIGH
PRESSURE RIDGE WILL THEN BUILD FROM THE MIDWEST TO OFF THE
ATLANTIC SEABOARD BY SAT...WITH A RIDGE AXIS SETTLING INTO THE
LOCAL AREA. TEMPS LOOK CLOSE TO NORMAL. LATE WEEK ONSHORE FLOW
SHOULD PUSH A FEW SHOWERS TOWARDS THE COAST...BUT POPS ARE TOO LOW
TO MENTION. OTHERWISE IT LOOKS DRY.
&&
.AVIATION...THRU 14/12Z
SFC WINDS: THRU 13/12Z...W/SW 4-8KTS. BTWN 13/12Z-13/15Z BCMG N/NW
8-12KTS. BTWN 13/15Z-13/23Z...N/NW 12-15KTS OCNL G18-22KTS. BTWN
13/23Z-14/02Z...BCMG N 4-7KTS.
VSBY/WX/CIGS: VFR ALL SITES.
&&
.MARINE...
TODAY-TONIGHT...POOR BOATING CONDITIONS AS A DRY COLD FRONT PUSHES
THRU THE LCL ATLC WATERS. A MODERATE TO FRESH WRLY BREEZE THRU
DAYBREAK WILL VEER TO N/NW BY MIDDAY AS THE FRONT PUSHES THRU. ROUGH
SEAS AS WINDS MAKE THE SHIFT FROM AN OFFSHORE COMPONENT TO A NRLY
COMPONENT THAT WILL BLOW OPPOSITE TO THE GULF STREAM CURRENT.
PREVAILING WAVE HEIGHTS INCREASING FROM 2-4FT TO 4-6FT NEARSHORE...
AND FROM 4-6FT TO 5-7FT OFFSHORE. STEEP WAVES WITH DOMINANT PDS BTWN
5-7SEC. CURRENT ADVISORY/CAUTION ORIENTATION LOOKS FINE FOR NOW...
BUT MAY NEED TO EXPAND THE ADVISORY TO INCLUDE NEARSHORE TREASURE
COAST WATERS BY LATE AFTN DUE TO THE GULF STREAM`S CLOSER PROXIMITY
TO THE COAST.
SUN-MON...BREEZY NORTHEAST/EAST WINDS SUN WILL VEER TO SOUTHEAST
ON MON. THIS WILL KEEP CONDITIONS POOR FOR SMALL CRAFT OPERATION.
MON NIGHT-WED...BREEZY SOUTH FLOW IS INDICATED FOR MON NIGHT. THIS
WILL TRANSPORT MOISTURE NORTHWARD AND BRING A CHANCE OF SHOWERS
AND A SLIGHT CHANCE FOR STORMS. MODELS DIFFER A BIT ON THE TUE-
WED WINDS BUT OVERALL THE TREND IS FOR A WEAKER FRONTAL PASSAGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 60 45 63 54 / 0 0 20 20
MCO 68 44 67 54 / 0 0 10 10
MLB 67 50 65 58 / 0 0 20 20
VRB 69 51 68 58 / 0 0 20 20
LEE 65 41 66 52 / 0 0 10 10
SFB 65 43 66 53 / 0 0 10 10
ORL 67 44 66 53 / 0 0 10 10
FPR 69 52 68 58 / 0 0 20 20
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 4 AM EST SUNDAY FOR SEBASTIAN INLET
TO JUPITER INLET 20-60 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM EST SUNDAY FOR FLAGLER BEACH TO
VOLUSIA-BREVARD COUNTY LINE 20-60 NM-VOLUSIA-BREVARD COUNTY
LINE TO SEBASTIAN INLET 20-60 NM.
&&
$$
SHORT TERM...BRAGAW
LONG TERM....LASCODY
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
316 AM EST SAT FEB 13 2016
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS BROAD BUT AMPLIFIED
UPPER LEVEL TROUGHING IN PLACE OVER THE EASTERN THIRD OF THE
NATION. TROUGH IS ANCHORED BY A BROAD AND COLD UPPER LOW OVER
EASTERN CANADA. FURTHER UPSTREAM WE FIND RIDGING THROUGH THE
INTER-MOUNTAIN WEST...AND SHORTWAVE ENERGY ARRIVING OVER THE
PACIFIC NORTHWEST/BRITISH COLUMBIA. BACK TO HOME...OUR REGION
RESIDES WITHIN DEEP LAYER NW FLOW ON THE BACKSIDE OF THE EASTERN
LONGWAVE TROUGH. SHORTWAVE ENERGY EMBEDDED WITHIN THE FLOW HAS
EXITED OFF THE GA/CAROLINA COAST EARLY THIS MORNING. THIS PUSH IS
DRIVING A WEAK COLD FRONT AT THE SURFACE DOWN FROM THE NORTH INTO
THE FLORIDA PENINSULA. THE COLD FRONT IS CURRENTLY DROPPING SOUTH
OVER THE NATURE COAST ZONES...AND SHOULD REACH THE I-4 CORRIDOR
TOWARD SUNRISE...AND THEN EXIT SOUTH OF FORT MYERS BY MIDDAY.
THIS IS A DRY FRONTAL PASSAGE WITH VERY LITTLE ATMOSPHERIC
MOISTURE ABOVE 850MB. NARROW BAND OF LOW 2-4KFT CLOUDS LEADS THE
FRONT...BUT THAT IS JUST ABOUT IT. THE FRONT WILL BE MOST MARKED
BY A WIND SHIFT TO THE NORTH. LIKELY TO SEE SOME PATCHY FOG
DEVELOPMENT IN THE PRE-DAWN HOURS AS WE GET SOME LOW LEVEL
MOISTURE POOLING AHEAD OF THE FRONTAL BOUNDARY. THIS FOG MAY
RESULT IN SOME TRICKY SPOTS FOR THE MORNING COMMUTE...BUT IT WILL
NOT LAST LONG ONCE THE SUN COMES UP DUE TO THE COMBINATION OF
DIURNAL MIXING...DRY AIR ADVECTION BEHIND THE FRONT.
&&
.SHORT TERM (TODAY THROUGH SUNDAY)...
AS MENTIONED IN THE SYNOPSIS...WEAK COLD FRONT WILL CROSS THE
REGION THIS MORNING...AND BE SOUTH OF OUR ZONES BY THE AFTERNOON
HOURS. THE AIRMASS CHANGE BEHIND THIS FRONT IS A BIT COOLER...BUT
THE BIGGER CHANGE WILL BE IN THE MOISTURE AS DEWPOINTS QUICKLY
DROP FROM NORTH TO SOUTH DURING THE DAY. IN FACT...AFTERNOON HIGH
TEMPS WILL BE GENERALLY SEASONABLE...RANGING FROM THE LOWER 60S
FAR NORTH TO THE MID/UPPER 60S CENTRAL...AND INTO THE LOWER 70S
SOUTH. AFTER THE EARLY BAND OF CLOUDS...SKIES WILL BE MOSTLY SUNNY
FOR THE MAJORITY OF THE DAY.
THE FORECAST FOR TONIGHT IS COLDER...MAINLY DUE TO THE DRY AIR
THAT WILL BE IN PLACE. HIGH PRESSURE DOES BUILD IN FROM THE
NORTH...BUT THE RIDGE CENTER STAYS UP OVER THE MID-ATLANTIC STATES
AND NEVER REALLY ALLOWS THE GRADIENT TO SLACKEN SUFFICIENTLY FOR
IDEAL RADIATIONAL COOLING OVER OUR ZONES. AT THE VERY LEAST...THE
RADIATIVE PROCESS WILL BE SLOWED...AND DOUBT MOST PLACES (OTHER
THAN EXTREMELY WELL SHELTERED LOCATIONS) WILL BE ABLE TO DECOUPLE
OVERNIGHT. SO...WHILE THE WIND MAY HELP KEEP MORE LOCATIONS ABOVE
FREEZING...IT WILL LOWER THE POTENTIAL WIND CHILL VALUES FOR
EARLY SUNDAY MORNING. DEEPEST INTO THE AIRMASS AND BEST POTENTIAL
FOR RADIATIVE PROCESSES WILL BE OUR FAR NORTHERN ZONES. ALLOW
INTERIOR LEVY COUNTY TO TOUCH 32 BRIEFLY AT DAWN...BUT OTHERWISE
KEEP TEMPS ABOVE FREEZING. RANGE LOW TEMPS FROM THESE LOWER 30S
OVER LEVY COUNTY...TO THE UPPER 30S/LOWER 40S BY THE I-4
CORRIDOR...AND GENERALLY IN THE LOWER/MID 40S FURTHER SOUTH.
LOCATIONS SUCH AS SOUTHERN PINELLAS COUNTY AND THE ISLANDS/CAPES
OF CHARLOTTE HARBOR WILL BE A BIT WARMER WITH NORTHEAST FLOW OFF
WATER. AGAIN THOUGH...WINDS WILL NOT BE STRONG...BUT WILL NOT BE
CALM EITHER. WIND CHILL VALUES ARE CURRENTLY FORECAST TO DROP INTO
THE 30S LATE TONIGHT AS FAR SOUTH AS SARASOTA/DE SOTO/HIGHLANDS
COUNTIES. NORTH OF BROOKSVILLE...WIND CHILL VALUES MAY BRIEFLY
DROP INTO THE 20S.
HIGH PRESSURE SHIFTS OFF THE ATLANTIC SEABOARD DURING
SUNDAY...SHIFTING OUR WINDS TO THE EAST. THIS FLOW WILL BRING A
SLOW INCREASE IN LOW LEVEL MOISTURE BACK ACROSS THE PENINSULA FROM
THE ATLANTIC. FOR OUR FORECAST...THIS MAINLY JUST MEANS A RETURN
TO A SCT CUMULUS FIELD FOR THE AFTERNOON HOURS. MANY GUIDANCE
MEMBERS ARE SHOWING SOME CONVERGENCE SHOWERS ALONG THE FLORIDA
EAST COAST ON SUNDAY THAT WILL ATTEMPT TO MIGRATE INLAND. NOT
COMPLETELY SOLD ON THIS POTENTIAL AS THE MOISTURE DEPTH IS REALLY
LACKING. HOWEVER...WILL ADD MENTION OF A FEW ISOLATED SPRINKLES
AFTER 18Z SUNDAY ACROSS FAR EASTERN POLK/HIGHLANDS COUNTIES. ANY
SPRINKLES WILL HAVE LIMITED TO NO IMPACT ON ANY OUTDOOR
ACTIVITIES. TEMPERATURES REGION-WIDE FOR SUNDAY SHOULD RECOVER
FROM THE CHILLY MORNING TEMPS TO THE 60S FOR THE AFTERNOON.
&&
.LONG TERM (MONDAY THROUGH NEXT FRIDAY)...
AN UPPER TROUGH INITIALLY FROM MANITOBA TO THE WESTERN GULF OF
MEXICO WILL SHARPEN AND SHIFT INTO THE EASTERN COASTAL STATES
TUE...AS A SURFACE LOW FORMS ON THE GULF COAST AND TRACKS TO THE MID-
ATLANTIC STATES. THE LOW TRAILS A COLD FRONT INTO THE EASTERN GULF
MON NIGHT AND ACROSS FL TUE. AS THE UPPER TROUGH AND SURFACE LOW
MOVE EAST A RIDGE OF HIGH PRESSURE ALONG THEE EASTERN SEABOARD
SLIDES EAST. AS IT DOES THE LOW LEVEL FLOW VEERS FROM EASTERLY TO
SOUTHERLY BY MON NIGHT...HELPING TO MOISTEN THE ATMOSPHERE ALTHOUGH
MODELS ONLY INCREASE PWAT VALUES INTO THE 1 TO 1.5 INCH RANGE. BUT
THIS WILL BE ENOUGH ALONG WITH THE UPPER TROUGH AND COLD FRONT FOR
SHOWERS AND THUNDERSTORMS...STARTING MON AFTERNOON THEN ENDING TUE
AS THE FRONT EXITS TO THE EAST. THE GREATEST ODDS OF SHOWERS AND
STORMS WILL BE MON NIGHT AND EARLY TUE MORNING. CURRENTLY THE BEST
DYNAMICS FOR SEVERE STORMS APPEAR TO STAY NORTH OF THE AREA.
FOR WED THROUGH FRI - THE UPPER TROUGH SLOWLY SLIPS OFFSHORE AS AN
UPPER RIDGE BUILDS NORTHWARD OVER THE WESTERN STATES THEN MOVES
ACROSS THE EASTERN STATES AS IT FLATTENS SOME. SURFACE HIGH PRESSURE
BUILDS IN OVER THE MID-MISSISSIPPI VALLEY THEN MIGRATES TO THE
ATLANTIC COAST WATERS. A DRY AND STABLE AIRMASS WILL BE IN PLACE
TEMPERATURES RUNNING CLOSE TO SEASONAL. WINDS REMAIN RATHER
MODEST...ONLY BRIEFLY APPROACHING 20 KNOTS ON THE GULF MON AND
TUE AHEAD OF THE FRONT.
&&
.AVIATION...
A NARROW BAND OF BKN MVFR CIGS WILL CONTINUE TO DROP SOUTH THROUGH
THE REGION EARLY THIS MORNING IN ADVANCE OF A WEAK COLD FRONT.
THIS FRONT WILL CROSS THE TAMPA BAY AREA AROUND SUNRISE...AND THEN
PASS SOUTH OF KFMY/KRSW LATER IN THE MORNING. WINDS SHIFT
NORTHERLY BEHIND THIS FRONT...AND THE NORTHEASTERLY TONIGHT. A
BRIEF PERIOD OF MVFR CIGS IS POSSIBLE AHEAD OF THE FRONT...WITH
PATCHY FOG ALSO DEVELOPING BEFORE DAWN. A PERIOD OF IFR/MVFR VIS
IS ALSO POSSIBLE THROUGH 13Z...WITH KLAL/KPGD MOST LIKELY TO SEE
THE VIS RESTRICTIONS. PREVAILING VFR CONDITIONS ARE THEN FORECAST
THROUGH 12Z SUNDAY.
&&
.MARINE...
A WEAK COLD FRONT DROPS SOUTHWARD THROUGH THE FORECAST WATERS THIS
MORNING. WINDS WILL SHIFT TO THE NORTH BEHIND THIS FRONT REACHING
CAUTIONARY LEVELS AT TIMES...OUTSIDE OF THE BAYS AND HARBORS. HIGH
PRESSURE MOVING NORTH OF THE REGION TONIGHT WILL SHIFT WINDS TO
THE NORTHEAST...WITH THE POTENTIAL FOR A MORE WIDESPREAD PERIOD OF
CAUTIONARY LEVEL WINDS. WINDS SHIFT EAST ON SUNDAY AND DIMINISH
BELOW HEADLINE CRITERIA BY THE AFTERNOON HOURS. THE NEXT COLD
FRONT CROSSES THE EASTERN GULF OF MEXICO MONDAY NIGHT AND EARLY
TUESDAY. WINDS CURRENTLY ARE NOT EXPECTED TO REACH HEADLINE
CRITERIA BEHIND THIS FRONT THROUGH THE DAYLIGHT HOURS OF
WEDNESDAY.
&&
.FIRE WEATHER...
A MUCH DRIER AIRMASS WILL ARRIVE ON NORTHERLY WINDS TODAY IN THE
WAKE OF A WEAK COLD FRONT. WITH THE DRY AIR...RELATIVE HUMIDITY
VALUES ARE FORECAST TO DROP BELOW 35 PERCENT FOR SEVERAL HOURS
THIS AFTERNOON AS FAR SOUTH AS SARASOTA/DE SOTO/HIGHLANDS
COUNTIES. NORTH OF THE I-4 CORRIDOR...RELATIVE HUMIDITY IS
EXPECTED TO DROP INTO THE 20S FOR A TIME. ALTHOUGH IT WILL BE
DRY...RED FLAG CONDITIONS ARE NOT FORECAST AS ERC VALUES REMAIN
AT OR BELOW 25...AND WINDS WILL STAY BELOW CRITICAL LEVELS. LOW
LEVEL MOISTURE BEGINS TO INCREASE DURING SUNDAY ON LIGHT EASTERLY
FLOW...AND THIS MOISTURE RETURN CONTINUES INTO MONDAY. AFTER THIS
AFTERNOON...CRITICAL LEVELS OF RELATIVE HUMIDITY ARE NOT EXPECTED
THROUGH THE EARLY PORTION OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 65 43 68 54 / 0 0 0 0
FMY 73 47 72 55 / 0 0 0 0
GIF 69 43 66 53 / 0 0 10 10
SRQ 67 44 68 54 / 0 0 0 0
BKV 65 38 67 49 / 0 0 0 0
SPG 65 48 67 56 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...BEACH HAZARDS STATEMENT THROUGH SUNDAY EVENING FOR COASTAL
CHARLOTTE-COASTAL LEE-COASTAL MANATEE-COASTAL
SARASOTA.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WEATHER...MROCZKA
LONG TERM/DECISION SUPPORT...RUDE
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1128 PM CST FRI FEB 12 2016
.UPDATE...
ISSUED AT 859 PM CST FRI FEB 12 2016
Skies have become clear this evening and should remain that way
the rest of the night. Any additional clouds will be very late
tonight or early tomorrow morning and be cirrus clouds. Winds
remain gusty and am expecting this to continue as forecast as
well. Gusty winds will keep air mixed, but dewpoints are in the
single digits over most of the area, so still think temps by
morning will be in the single digits to just below zero in the
northwest. Only change needed is to adjust cloud cover to better
reflect current conditions. Update will be out shortly.
&&
.SHORT TERM...(Tonight)
ISSUED AT 255 PM CST FRI FEB 12 2016
A weak clipper system will exit southeast of central IL late this
afternoon, with its diminishing area of very light snow/flurries
se of the IL river ending soon, with best light snow chances east
of IL over central IN. MVFR clouds already scattering nw of the IL
river like at PIA and HRRR model handling this clearing well.
These clouds to decrease se of the IL river during late
afternoon/early evening, and over southeast IL by mid evening.
Brisk NW winds of 15-25 mph and gusts to 30 mph will gradually
diminish during the night, reaching 5-15 mph later tonight. Strong
1046 mb polar high pressure west of Lake Winnipeg Canada to settle
se into MN/IA by sunrise Sat and bring a frigid night to the
region. Lows by early Saturday morning range from around zero
north of I-72 to 4-8F in southeast IL from I-70 southeast. Wind
chills by dawn will range from 5-15 below zero with a few spots
from I-74 north dipping to 15-17 below zero like at Bloomington,
Galesburg and Champaign. Will hold off on a wind chill advisory
overnight into mid Sat morning, but will issue SPS to address
these bitter cold wind chills especially in our northern CWA.
.LONG TERM...(Saturday through Friday)
ISSUED AT 255 PM CST FRI FEB 12 2016
Very cold conditions expected to start the day Saturday across
central and southeast Illinois as Arctic high pressure builds across
the area. The relatively slight pressure gradient that will
accompany the surface high should keep Wind Chill values warmer than
advisory criteria for the most part, but high temperatures should
only top out in the teens.
Beyond the initially cold conditions, our attention turns to an
approaching clipper system, which is likely to be the most
significant weather system to impact the area over the next week.
This clipper has trended faster in recent model runs, with snow now
expected to start breaking locally after midnight Saturday
night/Sunday morning. The system will be pushing into a very dry
airmass which should limit the snow accumulation to some degree.
However, fairly strong isentropic ascent and mixing ratios of 2-3
G/KG over at least a 12 hour period should be able to produce 2"=4"
snow totals. In fact, would not be surprised if we need to boost
accumulations further once the exact track of the system is more
clear (it has trended s bit south in the latest runs). One other
thing that will need to be monitored is that the moisture depth is
progged to be rather shallow during the period of potential snow.
This fact is also a reason to limit snow accumulations for now, and
we also need to monitor the threat for freezing drizzle due to a
potential lack of ice crystals.
The faster trend of the clipper system should now have Monday ending
up dry. Another weak clipper system may impact the area Tuesday into
Tuesday night, but it does not appear significant at this time.
After that, the next chance for precipitation should not occur
before the end of the week. However, model agreement in the details
of the late week system is weak at best. Temperatures should
gradually be trending warmer next week, with well above normal
temperatures likely by the end of the week (near 50 degrees for
highs). If these trends hold, the late week system, if/when it
impacts the area, should be a rain producer.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 1128 PM CST FRI FEB 12 2016
VFR conditions will continue at all TAF sites next 24hrs. Clear
skies will continue overnight and through the afternoon. Models
bring in some high cirrus late tomorrow afternoon/early evening in
advance of the next weather system. The cirrus will thicken during
the evening hours, followed by some mid clouds around 12kft
reaching SPI and DEC later in the evening. Winds still a tad gusty
but not too bad so will not have any gusts in this forecast. Winds
will become lighter through the morning hours and then become
light and variable during the early evening. Later in the evening
winds will increase in speed some, but only reaching around
4-5kts. Wind direction will continue to be northwest through the
night but then switch so southeast during the evening after the
ridge goes by.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Auten
SHORT TERM...07
LONG TERM...BAK
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1241 AM EST SAT FEB 13 2016
.SYNOPSIS...
ISSUED AT 1235 AM EST SAT FEB 13 2016
THIS WEEKEND WILL FEATURE COLD TEMPERATURES WITH HIGHS INTO THE
MID TEENS TODAY AND NEAR 20 ON SUNDAY. LOWS TONIGHT WILL LIKELY
FALL TO NEAR ZERO DEGREES. LAKE EFFECT SNOW SHOWERS AND AREAS OF
BLOWING SNOW WILL CONTINUE TO IMPACT AREAS ACROSS FAR NORTHERN
INDIANA AND SOUTHWEST LOWER MICHIGAN TODAY...WITH LIGHTER
FLURRIES AND SNOW SHOWERS POSSIBLE ELSEWHERE. HIGH PRESSURE
BRIEFLY BUILDS IN FOR TONIGHT AND SUNDAY MORNING BEFORE SNOW
CHANCES RETURN LATER SUNDAY INTO EARLY MONDAY. TEMPERATURES WILL
MODERATE CLOSER TO NORMAL NEXT WEEK WITH SEVERAL CHANCES FOR LIGHT
PRECIPITATION.
&&
.UPDATE...
ISSUED AT 734 PM EST FRI FEB 12 2016
POST FNTL SHSN WITHIN EMERGING ARCTIC AIRMASS QUITE INTENSE IN
SPOTS YET THIS EVENING BUT WILL CONT TO DIMINISH AS UNSTABLE SFC
BASED LAPSE RATES DECAY W/SUNSET. REGARDLESS GROWING QUITE CONCERNED
W/UPSTREAM LAKE RESPONSE WITHIN EVOLVING/INTENSIFYING LL THERMAL
TROUGH. GENERAL CONSOLIDATION IN BANDING NOTED OVR THE LAST 3 HOURS
ALG A MUSKEGON TO ALLEGAN LINE...MIMICKING RECENT RAP MODEL
INDICATIONS AS LL FLW VEERS CONSIDERABLY W/UPSTREAM EXTENT. THIS
PRIMARY PLUME XPCD/MODELED TO INTENSIFY AS IT COMES SOUTH THROUGH
LT EVENING BFR LOCKING IN WITHIN ROUGHLY ALG A SOUTH
HAVEN...CASSOPOLIS...ELKHART...WARSAW LINE. BASED ON OBSVD RADAR
TRENDS...SUSPECT NR 1" PER HOUR PEAK SNOWFALL RATES WHICH MAY
REQUIRE SOME FORM OF HEADLINE ADJUSTMENT. WILL ATTM FOLLOW
EVOLUTION OF THIS BAND THROUGH MID EVENING AND MAKE A DECISION IF
NEEDED WELL BFR 11 PM.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 306 PM EST FRI FEB 12 2016
CDFNT MOVG RAPIDLY E-SE ACROSS THE CWA THIS AFTN ACCOMPANIED BY A
BAND OF SNOW SHOWERS. LAKE EFFECT SNOW SHOWERS DVLPG BEHIND THE
FRONT SHOULD GRDLY INTENSIFY THIS EVE AS CAA CONTS AND WINDS VEER
FROM AROUND 300 DEGREES TO 340 DEGREES AS A SECONDARY CDFNT
CURRENTLY OVER NRN LWR MI MOVES THROUGH OUR AREA. INVERSION BASE
FORECAST TO PEAK LATE THIS EVE AROUND 6500FT WITH SIGNIFICANT LAKE
INDUCED INSTABILITY (0-2KM THETA-E LAPSE RATES OVER THE LAKE
AROUND -2.5C/KM). CONVECTION ALLOWING MODELS SUGGEST A DOMINANT
BAND OR TWO WILL SET UP AROUND THIS TIME IMPACTING NORTHWEST
PORTION OF OUR CWA. HWVR, THESE OPTIMAL CONDITIONS FOR LES SHOULD
BE SHORT LIVED AS INVERSION FCST TO LOWER/LAKE INDUCED INSTABILITY
DECREASE LATE TONIGHT AND THROUGH THE DAY SATURDAY. DGZ WILL ALSO
BE VERY LOW GIVEN ARCTIC AIRMASS MOVG IN WHICH SHOULD LIMIT ACCUMS
BLO WHAT OTRWS MIGHT BE EXPECTED. ONLY MINOR CHANGE MADE TO
PREVIOUS FCST ACCUMS WITH TOTALS TONIGHT AND SATURDAY EXPECTED TO
BE IN THE 3-6" RANGE IN THE ADVISORY AREA WITH 1-3" IN COUNTIES
SURROUNDING ADVISORY AND <1" OVER THE REST OF THE CWA. LOCALLY
HIGHER AMOUNTS PSBL IF DOMINANT BAND PERSISTS OVER ANY GIVEN AREA
VERY LONG THIS EVENING. BOUNDARY LAYER WINDS FCST 15-25KT TONIGHT
WHICH SHOULD CAUSE CONSIDERABLE BLOWING DRIFTING OF THE POWDERY
LES, MAINLY IN THE NW ADVISORY AREA. LITTLE CHANGE MADE TO TEMPS
WITH LOWS TONIGHT IN THE 0-5 RANGE NE AND SW WHERE SOME PARTIAL
CLEARING EXPECTED AND 5-10 UNDER THE LAKE EFFECT CLOUD PLUME OVER
MOST OF THE REST OF THE CWA, WITH HIGHS SATURDAY ONLY 12-16.
MINIMUM WIND CHILLS TONIGHT AND SATURDAY MORNING EXPECTED TO BE IN
THE -5 TO -15 RANGE.
&&
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 306 PM EST FRI FEB 12 2016
LAKE EFFECT SNOW WILL TAPER OFF SATURDAY EVENING AS LOW LEVEL RIDGE
AXIS SHIFTS OVERHEAD AND INVERSION HEIGHTS LOWER. DGZ REMAINS ACTIVE
IN THE 00-06Z TIMEFRAME SO SOME LIGHT FLURRIES/SNOW SHOWERS EXPECTED
BUT ANY ADDITIONAL ACCUMULATION WILL BE VERY LIGHT. MAIN STORY FOR
SATURDAY NIGHT WILL BE VERY COLD TEMPS. LIGHT WINDS...PARTIALLY
CLEAR SKIES...AND FRESH SNOW WILL SUPPORT GOOD RADIATIONAL COOLING
POTENTIAL IN SPOTS. GRADIENT WIND/WAA AND CLOUDS BEGIN TO INCREASE
TOWARD 12Z BUT SHOULD STILL BE ENOUGH TIME FOR TEMPS TO DROP. KEPT
CLOSE TO INHERITED FORECAST...WHICH IS ON THE COLD SIDE OF
GUIDANCE...WITH LOWS AROUND ZERO. WILL LIKELY BE A HIGH DEGREE OF
VARIANCE IN FINAL NUMBERS THOUGH...DEPENDING ON EXACT CLOUD TRENDS.
CHANCE FOR LIGHT SNOW THEN QUICKLY RETURNS LATE SUNDAY AS NEXT
SHORTWAVE ROTATES THROUGH THE REGION. CONFLUENT FLOW OVER THE
EASTERN CONUS WILL INCREASINGLY SHEAR OUT AND WEAKEN THIS WAVE. CVA
BECOMES NEGLIGIBLE BY SUNDAY NIGHT WITH JUST SOME BROAD/WEAK 280-
285K ISENTROPIC ASCENT. DO SEE A DECENT MOISTURE SURGE THOUGH WITH
MIXING RATIOS OVER 2 G/KG. GIVEN STEADY...ALBEIT WEAK...ASCENT AND
POTENTIAL FOR HIGHER THAN CLIMO SNOW RATIOS...COULD CHURN OUT 1-2"
BY LATE MONDAY MORNING. BEST CHANCES FOR HIGHER AMOUNTS WILL BE IN
OUR SOUTHWEST WHERE BETTER MOISTURE AND FORCING RESIDE.
AFTER A BRIEF BREAK MONDAY NIGHT...THERE IS ANOTHER CHANCE FOR SNOW
TUESDAY/TUESDAY NIGHT AS POTENT NORTHERN STREAM SHORTWAVE DIVES
SOUTHEAST AND STRENGTHENS EAST COAST LOW. MODELS HAVE BEEN KEEPING
PRECIP SHIELD OF PRIMARY LOW JUST EAST OF OUR CWA BUT CONTINUE TO
STRUGGLE IMMENSELY WITH EXACT TRACK OF SECONDARY VORT MAX.
CONFIDENCE IN SNOW CHANCES REMAINS LOW AT THIS POINT WITH PARENT JET
ENERGY STILL WELL OUT OVER THE DATA-SPARSE NORTH PACIFIC. WILL
CONTINUE TO WATCH THIS PERIOD AND ADJUST AS MODELS GET A BETTER
HANDLE ON SITUATION. SOME MINOR LAKE EFFECT THEN POSSIBLE WEDNESDAY
WITH MUCH WARMER TEMPS (AND POTENTIAL FOR RAIN) STILL EXPECTED BY
THE END OF THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1235 AM EST SAT FEB 13 2016
NW FLOW LAKE EFFECT EVENT WILL CONTINUE TO PROVIDE VARIABLE
FLIGHT CONDITIONS AT KSBN THROUGH THE MORNING (VIS MAINLY IFR
WITH TIMES OF MVFR/LIFR)...WITH GRADUAL IMPROVEMENT ANTICIPATED
THIS AFTERNOON AS FLOW BACKS ALLOWING FOR DRY AIR ENTRAINMENT INTO
SHRINKING BOUNDARY LAYER. KFWA LIKELY TO GET CLIPPED BY PRIMARY
LAKE EFFECT BAND THROUGH 07Z WITH MVFR/IFR CONDITIONS ANTICIPATED.
IMPROVEMENT TO VFR/LIGHTER WINDS THEN EXPECTED FOR THE REMAINDER
OF THE NIGHT AT KFWA...WITH SCT SHSN/FLURRIES FILLING BACK IN
DURING THE DAY.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 4 PM EST /3 PM CST/ THIS AFTERNOON
FOR INZ003>005.
MI...WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ077>079.
OH...NONE.
LM...HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST THIS MORNING FOR
LMZ043-046.
GALE WARNING UNTIL 7 AM EST THIS MORNING FOR LMZ043-046.
&&
$$
UPDATE...T
SYNOPSIS...STEINWEDEL
SHORT TERM...JT
LONG TERM...AGD
AVIATION...STEINWEDEL
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
405 AM CST SAT FEB 13 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CST SAT FEB 13 2016
Areal expansion of stratus will be the main forecast challenge
heading through the morning hours, and should have a significant
impact of temperature trends through the day across the far north.
Some southeastward development of freezing fog is not out of the
question this morning, however the probability for freezing drizzle
in these areas of stratus is not looking quite as probable at this
time. A large temperatures gradient is expected this afternoon in
excess of 30 degrees from the Elkhart area which should be in the
60s...to Hays where highs will not likely exceed the 30s. A
shortwave now moving into the northern Rockies will affect the
northern and central high plains region by the overnight, having
very little impact on western Kansas other than pushing a cold
front/wind shift across the region before Sunday morning.
.LONG TERM...(Sunday THROUGH Friday)
ISSUED AT 348 AM CST SAT FEB 13 2016
Models
have been consistent with a followup/secondary vort lobe rotating
through a bit farther south about 24 hours later which will
improve chances for rain or snow late Sunday night into very early
Monday morning. The remainder of the forecast period will see
rising thicknesses and more northwest flow aloft, resulting in a
warming trend through at least Thursday. Could not rule out
another 80 degree reading by Thursday as a warm dry downslope
pattern once again develops and possibly critical fire weather
conditions.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Saturday NIGHT)
ISSUED AT 1209 AM CST SAT FEB 13 2016
The HRRR model develops/spreads near IFR stratus farther south
across the area over the next few hours and maintains it through
the mid to late moring hours. Freezing fog is not a given at any
of the terminals this morning, as the HRRR indicates the best
signal on the higher terrain in northeast CO, however we will
monitor trend going foreward incase it develops farther east.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 45 30 56 31 / 0 0 0 10
GCK 52 29 57 30 / 10 0 0 10
EHA 65 36 58 32 / 0 0 0 10
LBL 57 32 58 30 / 0 0 0 10
HYS 36 27 51 31 / 10 0 10 20
P28 43 31 58 33 / 0 10 0 10
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Russell
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
1226 AM CST SAT FEB 13 2016
...UPDATED AVIATION SECTION...
.SYNOPSIS...
ISSUED AT 213 PM CST FRI FEB 12 2016
An upper level ridge of high pressure is located over the Rockies
with a long wave trough over the east coast. This places the
Central High Plains under northwest flow aloft. High to mid levels
of the atmosphere over western Kansas are fairly dry leaving only
a few high clouds visible across western Nebraska and northwest
Kansas. Some of these clouds may make it into portions of west and
west central Kansas this afternoon. As we head to the surface, low
levels of the atmosphere are saturated across portions of central
and western Kansas leading to a deck of low stratus extending
north and east of a line from Colby to Kingman. This deck of
clouds is slowly shifting southeast, however, these clouds are
expected to dissipate over the next couple of hours. An area of
low pressure with associated stationary front is sprawled out
across eastern Colorado with a dome of high pressure filtering
into the Northern Plains. This will lead to winds backing from the
northeast this afternoon to more of an easterly direction this
evening.
&&
.SHORT TERM...(THIS EVENING THROUGH Saturday)
ISSUED AT 1245 PM CST FRI FEB 12 2016
Low clouds are expected to form once again over north, west
central, and north central Kansas tonight with mostly clear skies
expected elsewhere. This deck of clouds may be thick enough for
light freezing drizzle to fall, mainly north of Highway 96. Winds
look to back form an easterly direction this evening, then
shifting southeast by midnight. Low clouds are expected to extend
into Oklahoma by sunrise tomorrow but then slowly dissipate by mid
afternoon like we saw today. Winds take more of a southerly
direction with an increase in speed tomorrow as the area of low
pressure mentioned in the synopsis intensifies and slides into
southeastern Colorado. The dome of high pressure will continue to
build across Northern and Central Plains. As for temperatures,
lows tonight look to range from the upper teens across north
central Kansas to upper 20s across far southwestern Kansas. Highs
tomorrow are anticipated to range from the mid 30s across north
central Kansas to mid 60s across far southwestern Kansas.
.LONG TERM...(Saturday NIGHT THROUGH Friday)
ISSUED AT 213 PM CST FRI FEB 12 2016
The upper level ridge in mentioned in the short term gets pushed
south Friday night into the weekend as a shortwave moves into the
Intermountain West Saturday then Northern Plains Saturday night
into Sunday. Cloudiness will increase in coverage as this system
moves into the Plains Saturday night with decreasing cloudiness on
Sunday. No precipitation is expected with this system due to lake
of moisture. This system will also help push a cold front through
the area shifting winds to more of a northerly direction. A second
shortwave is progged to move through the area Sunday night into
Monday once again increasing cloud cover across western Kansas.
There may be enough low to mid level moisture to squeeze out some
light rain or snow Sunday night but most likely we will stay dry.
An upper level ridge builds into the western Untied States early
into the mid part of next week. This will allow warmer
temperatures to build back into the area but with the sacrifice of
no measurable precipitation expected. Models then suggest another
system moving into the area late next week but that being so far
out it is hard to tell the exact track. As for temperatures, highs
in the 50s are expected Sunday, then reaching to around 60 degrees
Monday. Lows Saturday night will start out around 30 degrees, with
lower 30s Sunday night and mid 30s Monday night. A warming trend
continues through the week with highs starting out Tuesday ranging
from upper 50s north to mid 60s south ending Thursday with highs
ranging from the upper 60s north to around 80 degrees across far
southwestern Kansas. Lows during this time frame start out in the
mid 50s Tuesday night ranging from the upper 30s to mid 40s
Thursday night.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z Saturday NIGHT)
ISSUED AT 1209 AM CST SAT FEB 13 2016
The HRRR model develops/spreads near IFR stratus farther south
across the area over the next few hours and maintains it through
the mid to late moring hours. Freezing fog is not a given at any
of the terminals this morning, as the HRRR indicates the best
signal on the higher terrain in northeast CO, however we will
monitor trend going foreward incase it develops farther east.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 45 30 56 32 / 0 0 10 20
GCK 52 30 57 31 / 10 0 10 20
EHA 64 37 58 33 / 0 0 10 10
LBL 57 32 58 32 / 0 0 10 10
HYS 36 27 52 31 / 10 0 10 20
P28 43 32 58 33 / 0 10 10 20
&&
.DDC Watches/Warnings/Advisories...NONE.
&&
$$
SYNOPSIS...Hovorka_42
SHORT TERM...Hovorka_42
LONG TERM...Hovorka_42
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1240 AM EST SAT FEB 13 2016
.SYNOPSIS...ARCTIC HIGH PRESSURE WILL BUILD INTO CENTRAL NC TODAY
AND SUNDAY. AN AREA OF LOW PRESSURE WILL APPROACH FROM THE WEST ON
MONDAY AND CROSS THE REGION MONDAY NIGHT AND TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 940 PM FRIDAY...
STARTING TO FINALLY SEE BETTER WEST TO EAST CLEARING OF MOISTURE
AROUND 6000-7000 FT AS A JET ON THE BACK SIDE OF THE UPPER TROUGH
APPROACHES AND NORTHWEST FLOW STRENGTHENS. LOW-LEVEL MOISTURE IS
STILL MORE PREVALENT ON THE COASTAL PLAIN WHERE SOME SUB-1000 FT
STRATUS IS LINGERING. A PERIOD OF PATCHY FOG MAY DEVELOP IN THE
SOUTHERN COASTAL PLAIN AS THE HIGHER LEVEL CLOUDS CLEARING (HINTED AT
BY SREF PROBS AND KFAY/KGSB RAP SOUNDINGS)...BUT IT WOULD LIKELY BE
BRIEF...PRIOR TO 06Z...WITH A NORTHWEST WIND AND COLD ADVECTION
FORECAST TO SLOWLY STRENGTHEN AFTER MIDNIGHT. OTHERWISE...WHILE WE
MAY SEE A SOME PATCHES OF STRATOCU DRIFT ACROSS THE AREA GIVEN ALL
THE MOISTURE BANKED UPSTREAM OF THE MOUNTAINS...CLEARING SKIES AND
COLD ADVECTION WILL PUSH LOWS INTO THE LOWER 20S NORTH AND WEST TO
UPPER 20S SOUTH AND EAST.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 300 PM FRIDAY...
AS EAST COAST TROUGH TRIES TO PULL OFF THE COAST...VERY STRONG COLD
AIR ADVECTION WILL ENSUE BEHIND THE EXITING COASTAL SYSTEM. WITH
VERY STRONG PRESSURE GRADIENT ACROSS THE AREA...COLD TEMPERATURES
AND STRONG WINDS WILL BE THE FORECAST PROBLEM OF THE DAY. EXPECT
WINDS TO REMAIN SUSTAINED OUT OF THE NORTH OR NORTHWEST AT 10-15 KTS
WITH GUSTS OF 25-30 KTS FOR MUCH OF THE DAYLIGHT HOURS. AFTER SUNSET
GUSTS WILL SUBSIDE. HIGH TEMPERATURES ONLY IN THE LOW TO MID 30S AND
WITH WIND CHILL VALUES IN THE UPPER 10S TO LOW 20S FOR MUCH OF THE
DAY. AS AN ASIDE...WITH THE COLD BUT ALSO DRY AIRMASS IN PLACE...MIN
RH VALUES WILL DIP DOWN INTO THE LOW 20S. COMBINE THESE VALUES WITH
THE HIGHER WINDS AND THERE WILL BE A SMALL INCREASE IN FIRE DANGER
SATURDAY IN OUR SOUTHERN COUNTIES THAT MAY SQUEAK INTO THE LOWER
40S.
SATURDAY NIGHT WILL SEE THE GUSTS SLACK OFF BUT SUSTAINED WINDS TO
REMAIN UP IN THE 5 TO 10 KT RANGE KEEP THINGS MIXED A LITTLE.
COMBINE THIS WITH VERY COLD EXPECTED LOW TEMPERATURES IN THE LOW TO
MID TEENS...WIND CHILL VALUES SATURDAY NIGHT WILL RESIDE IN THE 5-10
DEGREE RANGE. PREPARATIONS SHOULD BE MADE NOW TO PROTECT ANYTHING
SUSCEPTIBLE TO THE COLD WIND CHILLS...ESPECIALLY PETS. SOME CLOUDS
WILL BEGIN TO APPROACH THE AREA LATE SATURDAY NIGHT INTO SUNDAY
MORNING FROM THE WEST IN ADVANCE OF THE NEXT STORM SYSTEM.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 315 PM FRIDAY...
...STORM SYSTEM LIKELY TO BRING WINTRY WEATHER THREAT SUN NIGHT/MON
FOLLOWED BY HEAVY RAIN THREAT AND A FEW STORMS MON NIGHT/TUE...
SUNDAY: CONTINUED CHILLY WITH THE ARCTIC HIGH PRESSURE EXTENDING
FROM THE ERN GREAT LAKES DOWN THROUGH NC. WILL HAVE INCREASING
CLOUDS AHEAD OF THE APPROACHING STORM... AS OUR MID LEVEL FLOW
SHIFTS FROM FAST NORTHWESTERLY TO WEST-SOUTHWEST... A FUNCTION OF
PACIFIC NORTHWEST ENERGY DIVING INTO AN INITIALLY FLAT/BROAD CENTRAL
CONUS TROUGH CAUSING ITS AMPLIFICATION. STATISTICAL GUIDANCE STILL
SUPPORTS HIGHS FROM 29 NE TO 35 SW. -GIH
SUN NIGHT THROUGH TUE:
OVERVIEW: CONFIDENCE IS BEGINNING TO INCREASE REGARDING THE
TIMING... MOST PROBABLE PRECIP TYPE PATTERN... AND PRIMARY WEATHER
THREATS FOR THE INCOMING SYSTEM. LATEST GUIDANCE SHOWS A BIT QUICKER
ONSET... WITH PRECIP ARRIVING IN THE NRN/WRN CWA SUN NIGHT... AS
WELL AS A SLIGHTLY EARLIER DEPARTURE ON TUE. LONGWAVE TROUGHING WILL
CONTINUE TO AMPLIFY ALONG THE MISS VALLEY AS NRN STREAM ENERGY DROPS
INTO ITS BASE OVER THE GULF STATES... CULMINATING IN A NARROW DEEP
SHORTWAVE TROUGH TAKING ON A POSITIVE TILT AS IT SWINGS ENE INTO THE
CAROLINAS. AT THE SURFACE... THE POLAR HIGH SITUATED OVER THE
NORTHEAST AND MIDATLANTIC STATES SUN NIGHT CONTINUES TO PUSH
STEADILY NORTHEAST AND OFFSHORE THROUGH MON... WHILE A COASTAL FRONT
FORMS ALONG THE CAROLINA COAST EXTENDING BACK TO DEVELOPING LOW
PRESSURE OVER THE CENTRAL GULF STATES. THIS LOW THEN TRACKS EAST
THEN NE THROUGH WRN NC MON NIGHT/TUE MORNING BEFORE MOVING QUICKLY
INTO THE NORTHEAST STATES... WITH A TRAILING FRONT SWEEPING THROUGH
CENTRAL/ERN NC BY EARLY TUE AFTERNOON.
PRECIPITATION CHANCES: THE INITIAL PROCESSES TO FORCE ASCENT SUNDAY
NIGHT INTO EARLY MONDAY INCLUDING DPVA AND MOIST ISENTROPIC UPGLIDE
ARE RATHER WEAK AND FOCUSED PRIMARILY ON WRN AND NRN PORTIONS OF
CENTRAL NC. WILL TREND POPS UP TO LIKELY NW AND RETAIN HIGH CHANCES
ACROSS THE SOUTH AND EAST SUN NIGHT INTO MON MORNING... WITH QPF
FAIRLY LIGHT... UNDER A QUARTER INCH MAINLY IN THE NW. BUT THIS
CHANGES QUICKLY WITH THE ADDITION OF STRONG UPPER DIVERGENCE (DUE TO
IDEALLY JUXTAPOSED POLAR AND SUBTROPICAL JETS) AND VIGOROUS LOW
LEVEL MOISTURE TRANSPORT EAST OF THE LOW. WILL RAMP UP POPS FURTHER
TO CATEGORICAL WEST/LIKELY EAST LATE MON... THEN TO CATEGORICAL
EVERYWHERE MON NIGHT THROUGH TUE MORNING... ENDING SW TO NE TUE
AFTERNOON.
PTYPES: USING THE TOP-DOWN METHODOLOGY WITH CONSIDERATION OF THE
INITIALLY VERY COLD/DENSE NATURE OF THE SURFACE AIR MASS... THE
INITIAL COLD AIR ALOFT GIVING WAY TO A WARM NOSE... AND THE STRONG
LOW LEVEL WARM ADVECTION APT TO DISLODGE THIS SURFACE AIR MASS
GRADUALLY FROM SE TO NW MON EVENING... EXPECT THIS TO START AS
MOSTLY LIGHT SNOW WITH PERHAPS PATCHY LIGHT SLEET SUN NIGHT ACROSS
THE NRN AND WRN CWA... FOLLOWED BY A SLOW STEADY TRANSITION FROM SSE
TO NNW TO FREEZING RAIN/SLEET THEN TO ALL RAIN... WITH THE FAR NW
COUNTIES INCLUDING THE TRIAD THE LAST TO SEE AN END TO THE WINTRY
PRECIP MON EVENING. TENTATIVE ACCUMULATIONS ARE UP TO ONE TO TWO
HUNDREDTHS OF AN INCH OF ICING (TRACE AMOUNTS) FOR MUCH OF THE
CWA... AND SNOW TOTALS OF 1-3" NW QUARTER WITH AN INCH OR LESS
ELSEWHERE... ALL OF WHICH SHOULD BE QUICKLY SWEPT AWAY BY MODERATE
TO POTENTIALLY HEAVY RAINFALL LATE MON NIGHT INTO TUE MORNING.
RAINFALL TOTALS AND STORM POTENTIAL: AT THIS TIME STORM TOTAL LIQUID
QPF IS EXPECTED TO BE 1-2" WITH LOCALLY HIGHER AMOUNTS POSSIBLE...
GIVEN THE HIGH WATER CONTENT AND STRONG LIFT MON NIGHT/TUE MORNING.
BASED ON THE ANTECEDENT CONDITIONS AND SEVERAL RIVERS AND CREEKS
RUNNING HIGH... A FLOOD WATCH MAY BE NEEDED FOR SOME PORTION OF THE
AREA. ALSO... WHILE LAPSE RATES ARE UNLIKELY TO BE VERY
IMPRESSIVE... THE STRONG AND FOCUSED LIFT POSSIBLE WITH THIS SYSTEM
AND WARMING LOW LEVELS ESPECIALLY IN THE SANDHILLS AND COASTAL PLAIN
MAY SUPPORT A FEW LIGHTNING STRIKES ON TUE.
TEMPS: EXPECT LOWS SUN NIGHT OF 22-26. TEMPS SHOULD SLOWLY RISE MON
THROUGH MON NIGHT... REACHING THE LOW 30S NW TO LOW 40S SE LATE
MON... RISING TO THE MID 30S NW TO MID 40S SE MON NIGHT... AND
PEAKING AT 48-56 TUE PRIOR TO FRONTAL PASSAGE.
WED THROUGH FRI: WE MAY SEE A PERTURBATION SWING THROUGH THE
LONGWAVE ERN TROUGH BASE ACROSS VA ON WED... BUT MODELS VARY ON THE
STRENGTH AND LATITUDE OF ANY SUCH WAVE... AND REGARDLESS THE
MOISTURE WILL BE LIMITED YIELDING NO IMPACTS ON CENTRAL NC OTHER
THAN SOME CLOUDS ACROSS THE NORTH. OTHERWISE... THIS PERIOD WILL
FEATURE A TRANSITION AWAY FROM WRN RIDGE/ERN TROUGH OVER THE
CONUS... AS FLAT RIDGING BUILDS OVER THE GULF/SOUTHEAST STATES FROM
THE WEST... WITH A NET RESULT OF DRY WEATHER AND NEAR TO SLIGHTLY
ABOVE NORMAL TEMPS FOR CENTRAL NC. -GIH
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1240 AM SATURDAY
A LAYER OF SCATTERED-BROKEN STRATOCU WILL LINGER ACROSS THE NORTHERN
COUNTIES THROUGH 10Z...THEN GRADUALLY DIMINISH. THE LEADING EDGE OF
AN ARCTIC AIRMASS WILL OVERSPREAD CENTRAL NC THROUGH 11Z. SFC WINDS
WILL GUSTS BETWEEN 20-25KTS WITH THE PASSAGE OF THE BOUNDARY.
AFTER 11Z...EXPECT VFR CONDITIONS WITH FEW-SCATTERED STRATOCU. SFC
WINDS WILL BE BRISK WITH GUSTS 22-27KTS HIGHLY PROBABLE FROM THE NW.
THESE BRISK WINDS WILL SLOWLY SUBSIDE LATER TONIGHT.
VFR CONDITIONS TO CONTINUE INTO SUNDAY THOUGH MID-HIGH LEVEL CLOUDS
WILL BE INCREASING DURING THE DAY AS AN AREA OF LOW PRESSURE APPROACHES
FROM THE WEST. MOISTURE AHEAD OF THIS SYSTEM WILL LEAD TO SUB VFR
CEILINGS ALONG WITH PATCHES OF PRECIPITATION LATE SUNDAY NIGHT INTO
MONDAY MORNING. AT ONSET...THIS PRECIPITATION MAY OCCUR AS A WINTRY
MIX. THE SUB VFR CONDITIONS MAY LINGER INTO EARLY TUESDAY WITH
IMPROVING CONDITIONS LATE TUESDAY INTO WEDNESDAY.
&&
.CLIMATE...
HERE ARE THE RECORD LOWS AND RECORD LOW MAXIMUM TEMPERATURES FOR SAT
FEB 13TH AND SUN FEB 14TH AT GSO... RDU... AND FAY:
REC YR REC YR
LOW LOW MAX
----------------------------------------------
GSO:
02/13 11 1955 31 1986
02/14 6 1905 22 1914
RDU:
02/13 4 1899 10 1899
02/14 -2 1899 27 1916
FAY:
02/13 14 1973 32 1955
02/14 12 1968 33 1916
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE
&&
$$
SYNOPSIS...WSS
NEAR TERM...SMITH
SHORT TERM...ELLIS
LONG TERM...HARTFIELD
AVIATION...WSS
CLIMATE...RAH
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1041 PM CST FRI FEB 12 2016
.DISCUSSION...SEE AVIATION SECTION FOR 06Z TAFS.
&&
.AVIATION...HIGHER BOUNDARY LAYER MOISTURE IS OVER THE COASTAL
PLAINS INTO THE EASTERN BRUSH COUNTRY LATE THIS EVENING WHILE
WINDS DIMINISHED. TEMPERATURE/DEWPOINT DEPRESSIONS ARE NEAR
ZERO OVER THE VICTORIA CROSSROADS. FOG/MVFR VSBYS EXPECTED TO
DEVELOP 05-06Z IN THIS REGION WITH CONDITIONS DETERIORATING TO
LIFR WITH DENSE FOG BY 07-08Z AND CONTINUE UNTIL AROUND 15Z.
TIMING FOR FOG IN THE ALI/CRP AREA WILL BE DELAYED AN HOUR OR TWO
WITH LIFR CONDS FORMING BY 08-09Z. EXPECT THE LOW CLOUDS AND
FOG...IFR CIGS AND MVFR VSBYS...WILL REACH LRD AREA BY 11Z WITH
LIFR VSBYS POSSIBLE IN NEAR DENSE FOG. VSBYS ARE EXPECTED TO
IMPROVE BY 15-16Z TO VFR WITH MVFR CIGS HOLDING OVER VCT AREA
THROUGH THE LATE MORNING BEFORE LIFTING. STRATUS IS EXPECTED TO
MOVE BACK INTO THE VCT AREA AROUND 03Z SUNDAY.
&&
.PREV DISCUSSION... /ISSUED 914 PM CST FRI FEB 12 2016/
DISCUSSION...DEWPOINT TEMPERATURES HAVE RISEN TO THE UPPER 50S
TO NEAR 60 OVER THE COASTAL PLAINS THIS EVENING. WINDS WILL
CONTINUE TO DIMINISH TONIGHT AS A WEAK FRONTAL BOUNDARY FROM
NORTH OF HOUSTON TO SOUTH OF SAN ANTONIO REMAINS ESSENTIAL
QUASISTATIONARY TONIGHT. TEMP-DEWPOINT DEPRESSIONS WERE THE
LOWEST AROUND THE MID COAST AT 03Z. 00Z HRRR ALONG WITH 00Z
NAM SHOW FOG WILL FORM OVER THE MID COAST REGION INITIALLY
JUST AFTER 06Z AND SPREAD WESTWARD INTO THE BRUSH COUNTRY
OVERNIGHT. ADDED CALHOUN AND ARANSAS COUNTIES INTO THE DENSE
FOG ADVISORY. MAY NEED TO HAVE ADVISORY FOR WEBB AND LA SALLE
COUNTIES LATER TONIGHT BUT NOT CONFIDENT ENOUGH AT THIS POINT
TO INCLUDE IN THE ADVISORY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 55 74 57 78 56 / 0 10 10 10 0
VICTORIA 50 71 54 75 57 / 0 10 10 10 10
LAREDO 54 82 55 83 53 / 0 0 0 0 0
ALICE 52 78 54 82 55 / 0 0 10 10 0
ROCKPORT 56 70 60 73 60 / 0 10 10 10 10
COTULLA 50 80 54 83 51 / 0 0 0 0 0
KINGSVILLE 52 77 54 78 56 / 0 0 0 10 10
NAVY CORPUS 56 71 60 73 59 / 0 10 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY FROM 2 AM TO 10 AM CST SATURDAY FOR THE
FOLLOWING ZONES: ARANSAS...BEE...CALHOUN...DUVAL...GOLIAD...
JIM WELLS...KLEBERG...LIVE OAK...MCMULLEN...NUECES...
REFUGIO...SAN PATRICIO...VICTORIA.
GM...NONE.
&&
$$
TMT/89...AVIATION
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1013 PM MST FRI FEB 12 2016
.UPDATE...
ISSUED AT 1010 PM MST FRI FEB 12 2016
WEBCAMS NEAR CARPENTER IN EASTERN LARAMIE COUNTY...ALONG WITH
DECREASING VISIBILITIES REPORTED AT PINE BLUFFS...LED ME TO EXPAND
THE DENSE FOG ADVISORY FURTHER WEST. LATEST HRRR GUIDANCE AND
11-3.9U SATELLITE IMAGERY SHOWING THIS AS WELL...SO CONFIDENCE IS
HIGH ON EXPANDING THIS ADVISORY. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 806 PM MST FRI FEB 12 2016
LATEST IBM AND SNY OBSERVATIONS IN THE SOUTHERN PANHANDLE SHOWING
VISIBILITIES DOWN NEAR 1/4 MILE. THESE VISIBILITY REPORTS HAVE NOT
CHANGED MUCH OVER THE PAST HOUR. LATEST 11-3.9U SATELLITE IMAGERY
SHOWING THE LOW CLOUDS/FOG SPREADING WEST TOWARDS LARAMIE COUNTY
NEAR PINE BLUFFS. WILL CONTINUE TO MONITOR AND MAY NEED TO EXTEND
THE ADVISORY FURTHER WEST. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 708 PM MST FRI FEB 12 2016
GETTINGS REPORTS FROM THE SIDNEY AND KIMBALL ASOS/AWOS OF REDUCED
VISIBILITIES IN FOG ALREADY THIS EVENING. CERTAINLY NEED TO WATCH
CONDITIONS TO SEE IF THIS FOG BECOMES MORE WIDESPREAD. WENT AHEAD
AND EXPANDED FOG WEST UP THE PLATTE RIVER VALLEY INTO TORRINGTON
AND ACROSS THE NORTHERN PANHANDLE AS WELL. WILL CONTINUE
MONITORING. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 300 PM MST FRI FEB 12 2016
EARLY AFTERNOON WATER VAPOR IMAGERY SHOWED A UPPER RIDGE AXIS
SITUATED OVER THE INTERMTN WEST WITH A DEEP UPPER TROUGH FROM
HUDSON BAY CANADA TO FL. NORTHWEST FLOW ALOFT PREVAILED ACROSS
THE FRONT RANGE AND HIGH PLAINS. THE LEADING EDGE OF A SHALLOW
COLD AIR MASS HAD DRIFTED WEST INTO THE EASTERN 1/3 OF THE COWBOY
STATE. EAST-NORTHEAST WINDS AND WESTERN EDGE OF STRATUS CLOUD
DECK EXTENDED FROM NEAR LUSK WY TO JUST WEST OF SIDNEY NE.
TEMPERATURES EAST OF THE FRONT WERE IN THE 20S AND 30S...WHILE
WESTERLY WINDS AND 40S PREVAILED TO THE WEST.
DURING THE NEXT 12-18 HOURS...PRIMARY CONCERNS WILL DEAL WITH
POTENTIAL FOR PATCHY FREEZING DRIZZLE AND FOG OVER WESTERN
NE PANHANDLE ASSOCIATED WITH THE SHALLOW COLD AIR MASS. THERE
IS GOOD MODEL AGREEMENT PROGGING THE ARCTIC FRONT TO REMAIN
NEARLY STATIONARY TONIGHT ACROSS THE EASTERN WY PLAINS THEN
SLOWLY SHIFTING EAST INTO WESTERN NE SATURDAY MORNING. LATEST
GFS/NAM BUFR SOUNDINGS INDICATE A NEARLY SATURATED LAYER FROM
700-950MB ALONG WITH A LIGHT LOW LEVEL SOUTHEASTERLY FLOW
TONIGHT AND EARLY SATURDAY MORNING OVER WESTERN NE. PATCHY
FREEZING DRIZZLE AND FOG DEVELOPING LATER THIS EVENING AND
LINGERING THROUGH MID-LATE MORNING. THE FOG/DRIZZLE MAY EXTEND
AS FAR WEST AS A LUSK WY-KIMBALL NE LINE...BUT CONFIDENCE NOT
HIGH ATTM AND NEXT SHIFT CAN REEVALUATE WITH 00Z MODEL GUIDANCE.
A SHORTWAVE TROUGH ENTERING THE PACIFIC NORTHWEST TONIGHT WILL
QUICK MOVE ACROSS THE ID/MT SATURDAY MORNING...NORTHERN WY
SATURDAY AFTERNOON...AND SD/NORTHERN NE SATURDAY NIGHT. THIS
SHORTWAVE WILL INCREASE THE LEESIDE SURFACE PRESSURE GRADIENT
WITH THE POTENTIAL FOR A GAP WIND EPISODE FOR ARLINGTON AND
BORDEAUX SATURDAY AFTERNOON AND EVENING. THE CRAIG-CASPER HEIGHT
700-850MB GRADIENT EXCEEDS 60M BY 21Z SATURDAY...AND DECREASED
BELOW 50M BY 06Z SUNDAY. WINDS AT 700MB PEAK NEAR 60 KT AT 00Z
SUNDAY. ISSUED A HIGH WIND WATCH FOR WY ZONES 106 AND 110 FROM
NOON TO 9 PM SATURDAY FOR THE POTENTIAL FOR WEST WIND GUSTS TO
60 MPH. SATURDAY WILL BE MILDER...ESPECIALLY EAST OF I-25 AS
WESTERLY DOWNSLOPING WINDS SCOUR OUT THE SHALLOW COLD AIR MASS.
AFTER A BRIEF LULL IN THE HIGH WINDS SATURDAY NIGHT...THEY PICK
UP AGAIN SUNDAY MORNING WITH THE POTENTIAL FOR HIGH WINDS SPREADING
EAST TO I-25 SUNDAY AFTERNOON. IF THE MODELS REMAIN
CONSISTENT...HIGH WIND HEADLINES MAY BE ISSUED SATURDAY. SUNDAY
WILL BE 5-10 DEGREES FOLLOWING THE PASSAGE OF A PACIFIC COLD FRONT.
SOME LIGHT PRECIPITATION DEVELOPS INITIALLY ACROSS NORTHEAST
WY/WESTERN SD SATURDAY EVENING AND SHIFTS EAST SATURDAY NIGHT.
PACIFIC MOISTURE INCREASES WEST OF THE LARAMIE RANGE SUNDAY
MORNING WITH LIGHT SNOW BECOMING MORE WIDESPREAD SUNDAY
AFTERNOON. THERE IS A SLIGHT CHANCE OF LIGHT SNOW SPREADING EAST
ONTO THE SOUTHEAST WY PLAINS SUNDAY NIGHT. MOST OF THE
ACCUMULATING SNOW WILL OCCUR OVER THE SNOWY/SIERRA MADRE RANGES
WITH UP TO 3 INCHES POSSIBLE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 200 PM MST FRI FEB 12 2016
MONDAY...RELATIVELY MOIST NORTHWEST FLOW ALOFT WILL PRODUCE
OROGRAPHIC SNOWFALL ACROSS THE SNOWY AND SIERRA MADRE RANGES WITH
A SLIGHT CHANCE OF PRECIPITATION NORTH OF A DOUGLAS TO SCOTTSBLUFF
LINE.
TUESDAY...DRIER AND WARMER AS HEIGHTS AND THICKNESSES RISE AND THE
ATMOSPHERE DRIES OUT SOMEWHAT.
WEDNESDAY...PERHAPS THE WARMEST DAY NEXT WEEK AS THE RIDGE ALOFT
MOVES OVERHEAD AND SURFACE LEE TROUGHING BECOMES WELL ESTABLISHED
WITH VERY DRY ATMOSPHERE PROMOTING WARMING TEMPERATURES.
THURSDAY...CONTINUED MILD IN THE WARM SECTOR AHEAD OF APPROACHING
COLD FRONT. SOME OROGRAPHIC SNOW SHOWERS POSSIBLE NEAR THE SNOWY
AND SIERRA MADRE RANGES LATE IN THE DAY WITH A SHORTWAVE TROUGH
APPROACHING.
FRIDAY...COOLER IN THE WAKE OF THE SHORTWAVE TROUGH ALOFT AND ITS
ASSOCIATED COLD FRONT PASSAGE...THOUGH STILL RELATIVELY MILD FOR
MID FEBRUARY BASED ON PROJECTED HEIGHTS AND THICKNESSES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1010 PM MST FRI FEB 12 2016
BACKDOOR FRONT TO REMAIN ALONG THE EAST SLOPES OF THE LARAMIE
RANGE THROUGH THE OVERNIGHT HOURS. EASTERLY UPSLOPING WINDS OVER
THE PANHANDLE WILL CONTINUE WIDESPREAD IFR/LIFR CONDITIONS FOR OUR
NEBRASKA PANHANDLE AIRPORTS AT LEAST THROUGH 18Z. FOLLOWED LATEST
HRRR GUIDANCE AND CONFIDENCE IS HIGH THAT LOW CONDITIONS WILL
CONTINUE. WEST WINDS RETURN AFTER 18Z THAT WILL SCOUR OUT THE
LOWER STRATUS.
&&
.FIRE WEATHER...
ISSUED AT 200 PM MST FRI FEB 12 2016
NO FIRE WEATHER CONCERNS THROUGH THE WEEKEND WITH COOL TO MILD
TEMPERATURES AND RESIDUAL SNOW COVER. A NORTH-SOUTH ORIENTED COLD
FRONT OVER THE HIGH PLAINS WILL SHIFT EASTWARD SATURDAY AS A QUICK
MOVING UPPER LEVEL DISTURBANCE MOVES INTO NORTHERN WYOMING. THIS
DISTURBANCE WILL TIGHTEN THE LEESIDE SURFACE PRESSURE GRADIENT
WITH WEST WINDS BECOMING STRONG AND GUSTY ACROSS MUCH OF SOUTHEAST
WYOMING. THE WINDY CONDITIONS WILL CONTINUE SUNDAY AS WELL.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING
FOR WYZ106-110.
DENSE FOG ADVISORY UNTIL 5 AM MST SATURDAY FOR WYZ119.
NE...DENSE FOG ADVISORY UNTIL 5 AM MST SATURDAY FOR NEZ054-055.
&&
$$
UPDATE...GCC
SHORT TERM...MAJ
LONG TERM...RUBIN
AVIATION...GCC
FIRE WEATHER...MAJ
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
635 AM EST SAT FEB 13 2016
...UPDATED AVIATION DISCUSSION...
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS BROAD BUT AMPLIFIED
UPPER LEVEL TROUGHING IN PLACE OVER THE EASTERN THIRD OF THE
NATION. TROUGH IS ANCHORED BY A BROAD AND COLD UPPER LOW OVER
EASTERN CANADA. FURTHER UPSTREAM WE FIND RIDGING THROUGH THE
INTER-MOUNTAIN WEST...AND SHORTWAVE ENERGY ARRIVING OVER THE
PACIFIC NORTHWEST/BRITISH COLUMBIA. BACK TO HOME...OUR REGION
RESIDES WITHIN DEEP LAYER NW FLOW ON THE BACKSIDE OF THE EASTERN
LONGWAVE TROUGH. SHORTWAVE ENERGY EMBEDDED WITHIN THE FLOW HAS
EXITED OFF THE GA/CAROLINA COAST EARLY THIS MORNING. THIS PUSH IS
DRIVING A WEAK COLD FRONT AT THE SURFACE DOWN FROM THE NORTH INTO
THE FLORIDA PENINSULA. THE COLD FRONT IS CURRENTLY DROPPING SOUTH
OVER THE NATURE COAST ZONES...AND SHOULD REACH THE I-4 CORRIDOR
TOWARD SUNRISE...AND THEN EXIT SOUTH OF FORT MYERS BY MIDDAY.
THIS IS A DRY FRONTAL PASSAGE WITH VERY LITTLE ATMOSPHERIC
MOISTURE ABOVE 850MB. NARROW BAND OF LOW 2-4KFT CLOUDS LEADS THE
FRONT...BUT THAT IS JUST ABOUT IT. THE FRONT WILL BE MOST MARKED
BY A WIND SHIFT TO THE NORTH. LIKELY TO SEE SOME PATCHY FOG
DEVELOPMENT IN THE PRE-DAWN HOURS AS WE GET SOME LOW LEVEL
MOISTURE POOLING AHEAD OF THE FRONTAL BOUNDARY. THIS FOG MAY
RESULT IN SOME TRICKY SPOTS FOR THE MORNING COMMUTE...BUT IT WILL
NOT LAST LONG ONCE THE SUN COMES UP DUE TO THE COMBINATION OF
DIURNAL MIXING...DRY AIR ADVECTION BEHIND THE FRONT.
&&
.SHORT TERM (TODAY THROUGH SUNDAY)...
AS MENTIONED IN THE SYNOPSIS...WEAK COLD FRONT WILL CROSS THE
REGION THIS MORNING...AND BE SOUTH OF OUR ZONES BY THE AFTERNOON
HOURS. THE AIRMASS CHANGE BEHIND THIS FRONT IS A BIT COOLER...BUT
THE BIGGER CHANGE WILL BE IN THE MOISTURE AS DEWPOINTS QUICKLY
DROP FROM NORTH TO SOUTH DURING THE DAY. IN FACT...AFTERNOON HIGH
TEMPS WILL BE GENERALLY SEASONABLE...RANGING FROM THE LOWER 60S
FAR NORTH TO THE MID/UPPER 60S CENTRAL...AND INTO THE LOWER 70S
SOUTH. AFTER THE EARLY BAND OF CLOUDS...SKIES WILL BE MOSTLY SUNNY
FOR THE MAJORITY OF THE DAY.
THE FORECAST FOR TONIGHT IS COLDER...MAINLY DUE TO THE DRY AIR
THAT WILL BE IN PLACE. HIGH PRESSURE DOES BUILD IN FROM THE
NORTH...BUT THE RIDGE CENTER STAYS UP OVER THE MID-ATLANTIC STATES
AND NEVER REALLY ALLOWS THE GRADIENT TO SLACKEN SUFFICIENTLY FOR
IDEAL RADIATIONAL COOLING OVER OUR ZONES. AT THE VERY LEAST...THE
RADIATIVE PROCESS WILL BE SLOWED...AND DOUBT MOST PLACES (OTHER
THAN EXTREMELY WELL SHELTERED LOCATIONS) WILL BE ABLE TO DECOUPLE
OVERNIGHT. SO...WHILE THE WIND MAY HELP KEEP MORE LOCATIONS ABOVE
FREEZING...IT WILL LOWER THE POTENTIAL WIND CHILL VALUES FOR
EARLY SUNDAY MORNING. DEEPEST INTO THE AIRMASS AND BEST POTENTIAL
FOR RADIATIVE PROCESSES WILL BE OUR FAR NORTHERN ZONES. ALLOW
INTERIOR LEVY COUNTY TO TOUCH 32 BRIEFLY AT DAWN...BUT OTHERWISE
KEEP TEMPS ABOVE FREEZING. RANGE LOW TEMPS FROM THESE LOWER 30S
OVER LEVY COUNTY...TO THE UPPER 30S/LOWER 40S BY THE I-4
CORRIDOR...AND GENERALLY IN THE LOWER/MID 40S FURTHER SOUTH.
LOCATIONS SUCH AS SOUTHERN PINELLAS COUNTY AND THE ISLANDS/CAPES
OF CHARLOTTE HARBOR WILL BE A BIT WARMER WITH NORTHEAST FLOW OFF
WATER. AGAIN THOUGH...WINDS WILL NOT BE STRONG...BUT WILL NOT BE
CALM EITHER. WIND CHILL VALUES ARE CURRENTLY FORECAST TO DROP INTO
THE 30S LATE TONIGHT AS FAR SOUTH AS SARASOTA/DE SOTO/HIGHLANDS
COUNTIES. NORTH OF BROOKSVILLE...WIND CHILL VALUES MAY BRIEFLY
DROP INTO THE 20S.
HIGH PRESSURE SHIFTS OFF THE ATLANTIC SEABOARD DURING
SUNDAY...SHIFTING OUR WINDS TO THE EAST. THIS FLOW WILL BRING A
SLOW INCREASE IN LOW LEVEL MOISTURE BACK ACROSS THE PENINSULA FROM
THE ATLANTIC. FOR OUR FORECAST...THIS MAINLY JUST MEANS A RETURN
TO A SCT CUMULUS FIELD FOR THE AFTERNOON HOURS. MANY GUIDANCE
MEMBERS ARE SHOWING SOME CONVERGENCE SHOWERS ALONG THE FLORIDA
EAST COAST ON SUNDAY THAT WILL ATTEMPT TO MIGRATE INLAND. NOT
COMPLETELY SOLD ON THIS POTENTIAL AS THE MOISTURE DEPTH IS REALLY
LACKING. HOWEVER...WILL ADD MENTION OF A FEW ISOLATED SPRINKLES
AFTER 18Z SUNDAY ACROSS FAR EASTERN POLK/HIGHLANDS COUNTIES. ANY
SPRINKLES WILL HAVE LIMITED TO NO IMPACT ON ANY OUTDOOR
ACTIVITIES. TEMPERATURES REGION-WIDE FOR SUNDAY SHOULD RECOVER
FROM THE CHILLY MORNING TEMPS TO THE 60S FOR THE AFTERNOON.
&&
.LONG TERM (MONDAY THROUGH NEXT FRIDAY)...
AN UPPER TROUGH INITIALLY FROM MANITOBA TO THE WESTERN GULF OF
MEXICO WILL SHARPEN AND SHIFT INTO THE EASTERN COASTAL STATES
TUE...AS A SURFACE LOW FORMS ON THE GULF COAST AND TRACKS TO THE MID-
ATLANTIC STATES. THE LOW TRAILS A COLD FRONT INTO THE EASTERN GULF
MON NIGHT AND ACROSS FL TUE. AS THE UPPER TROUGH AND SURFACE LOW
MOVE EAST A RIDGE OF HIGH PRESSURE ALONG THEE EASTERN SEABOARD
SLIDES EAST. AS IT DOES THE LOW LEVEL FLOW VEERS FROM EASTERLY TO
SOUTHERLY BY MON NIGHT...HELPING TO MOISTEN THE ATMOSPHERE ALTHOUGH
MODELS ONLY INCREASE PWAT VALUES INTO THE 1 TO 1.5 INCH RANGE. BUT
THIS WILL BE ENOUGH ALONG WITH THE UPPER TROUGH AND COLD FRONT FOR
SHOWERS AND THUNDERSTORMS...STARTING MON AFTERNOON THEN ENDING TUE
AS THE FRONT EXITS TO THE EAST. THE GREATEST ODDS OF SHOWERS AND
STORMS WILL BE MON NIGHT AND EARLY TUE MORNING. CURRENTLY THE BEST
DYNAMICS FOR SEVERE STORMS APPEAR TO STAY NORTH OF THE AREA.
FOR WED THROUGH FRI - THE UPPER TROUGH SLOWLY SLIPS OFFSHORE AS AN
UPPER RIDGE BUILDS NORTHWARD OVER THE WESTERN STATES THEN MOVES
ACROSS THE EASTERN STATES AS IT FLATTENS SOME. SURFACE HIGH PRESSURE
BUILDS IN OVER THE MID-MISSISSIPPI VALLEY THEN MIGRATES TO THE
ATLANTIC COAST WATERS. A DRY AND STABLE AIRMASS WILL BE IN PLACE
TEMPERATURES RUNNING CLOSE TO SEASONAL. WINDS REMAIN RATHER
MODEST...ONLY BRIEFLY APPROACHING 20 KNOTS ON THE GULF MON AND
TUE AHEAD OF THE FRONT.
&&
.AVIATION (THROUGH 12Z SUNDAY)...
A NARROW BAND OF BKN MVFR CIGS WILL CONTINUE TO DROP SOUTH THROUGH THE
REGION EARLY THIS MORNING IN ADVANCE OF A WEAK COLD FRONT. THIS FRONT
IS CURRENTLY CROSSING THE I-4 CORRIDOR THROUGH KTPA/KPIE/KLAL...AND
WILL CONTINUE SOUTH OF KFMY/KRSW BY MIDDAY. MVFR CIGS AND PATCHY DENSE
FOG THROUGH THE I-4 TERMINALS WILL IMPROVE SHORTLY AFTER SUNRISE WITH
THE FRONTAL PASSAGE. WINDS SHIFT NORTHERLY BEHIND THE FRONT...AND THEN
NORTHEASTERLY TONIGHT. PREVAILING VFR CONDITIONS ARE FORECAST THROUGH
12Z SUNDAY FOR ALL TERMINALS AFTER THE PASSAGE OF THE FRONT THIS MORNING.
&&
.MARINE...
A WEAK COLD FRONT DROPS SOUTHWARD THROUGH THE FORECAST WATERS THIS
MORNING. WINDS WILL SHIFT TO THE NORTH BEHIND THIS FRONT REACHING
CAUTIONARY LEVELS AT TIMES...OUTSIDE OF THE BAYS AND HARBORS. HIGH
PRESSURE MOVING NORTH OF THE REGION TONIGHT WILL SHIFT WINDS TO
THE NORTHEAST...WITH THE POTENTIAL FOR A MORE WIDESPREAD PERIOD OF
CAUTIONARY LEVEL WINDS. WINDS SHIFT EAST ON SUNDAY AND DIMINISH
BELOW HEADLINE CRITERIA BY THE AFTERNOON HOURS. THE NEXT COLD
FRONT CROSSES THE EASTERN GULF OF MEXICO MONDAY NIGHT AND EARLY
TUESDAY. WINDS CURRENTLY ARE NOT EXPECTED TO REACH HEADLINE
CRITERIA BEHIND THIS FRONT THROUGH THE DAYLIGHT HOURS OF
WEDNESDAY.
&&
.FIRE WEATHER...
A MUCH DRIER AIRMASS WILL ARRIVE ON NORTHERLY WINDS TODAY IN THE
WAKE OF A WEAK COLD FRONT. WITH THE DRY AIR...RELATIVE HUMIDITY
VALUES ARE FORECAST TO DROP BELOW 35 PERCENT FOR SEVERAL HOURS
THIS AFTERNOON AS FAR SOUTH AS SARASOTA/DE SOTO/HIGHLANDS
COUNTIES. NORTH OF THE I-4 CORRIDOR...RELATIVE HUMIDITY IS
EXPECTED TO DROP INTO THE 20S FOR A TIME. ALTHOUGH IT WILL BE
DRY...RED FLAG CONDITIONS ARE NOT FORECAST AS ERC VALUES REMAIN
AT OR BELOW 25...AND WINDS WILL STAY BELOW CRITICAL LEVELS. LOW
LEVEL MOISTURE BEGINS TO INCREASE DURING SUNDAY ON LIGHT EASTERLY
FLOW...AND THIS MOISTURE RETURN CONTINUES INTO MONDAY. AFTER THIS
AFTERNOON...CRITICAL LEVELS OF RELATIVE HUMIDITY ARE NOT EXPECTED
THROUGH THE EARLY PORTION OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 65 43 68 54 / 0 0 0 0
FMY 73 47 72 55 / 0 0 0 0
GIF 69 43 66 53 / 0 0 10 10
SRQ 67 44 68 54 / 0 0 0 0
BKV 65 38 67 49 / 0 0 0 0
SPG 65 48 67 56 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...BEACH HAZARDS STATEMENT THROUGH SUNDAY EVENING FOR COASTAL
CHARLOTTE-COASTAL LEE-COASTAL MANATEE-COASTAL
SARASOTA.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WEATHER...MROCZKA
LONG TERM/DECISION SUPPORT...RUDE
AREA FORECAST DISCUSSION
NWS BISMARCK ND
951 AM CST SAT FEB 13 2016
.UPDATE...
ISSUED AT 947 AM CST SAT FEB 13 2016
NO SIGNIFICANT CHANGES WERE NEEDED FOR THIS UPDATE. DID INCREASE
PRECIPITATION CHANCES OVER THE WEST AND CENTRAL THROUGH 18Z...AS
MULTIPLE OBSERVATIONS ARE COMING IN WITH LIGHT SNOW WHERE THERE
HAVE BEEN LITTLE TO NO RADAR RETURNS. THINKING REMAINS THE SAME ON
WINTER WEATHER HEADLINES AS WE ENTER A HOLDING PATTERN...WITH LOW
PRESSURE NOW DEVELOPING OVER SOUTHERN SASKATCHEWAN AND NORTHERN
WYOMING.
UPDATE ISSUED AT 701 AM CST SAT FEB 13 2016
EXPANDED THE WINTER WEATHER ADVISORY INTO THE NORTH CENTRAL AND
TURTLE MOUNTAINS AREA FOR THIS AFTERNOON THROUGH TONIGHT WITH THIS
UPDATE.
THE FULL 00 AND 06 UTC DETERMINISTIC AND ENSEMBLE SUITES AND THE
08-11 UTC HRRR AND RAP ITERATIONS ALL SUPPORT THE POTENTIAL FOR
MODERATE SNOWFALL ACCUMULATIONS ACROSS THE NORTH CENTRAL AND
TURTLE MOUNTAINS AREA THIS AFTERNOON THROUGH TONIGHT. OVERALL...A
CONSENSUS OF THESE SOLUTIONS SUPPORTS GREATER QPF THAN THE
PREVIOUS FORECAST OVER MOST OF THE CWA THIS AFTERNOON THROUGH
TONIGHT...LEADING TO GREATER SNOWFALL TOTALS. OBSERVED TRENDS
ACROSS MONTANA THIS MORNING AND THE 12 UTC SUITE WILL HAVE TO BE
CLOSELY EVALUATED AS SOME LOCATIONS ACROSS CENTRAL NORTH DAKOTA
HAVE THE POTENTIAL TO APPROACH WARNING LEVEL SNOWFALL AS DEPICTED
IN 00 AND 06 UTC SUITES. HEAVY SNOWFALL RATES ARE POSSIBLE GIVEN
STEEP MID LEVEL LAPSE RATES ASSOCIATED WITH THE POTENT SHORTWAVE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CST SAT FEB 13 2016
THE FOCUS OF THE SHORT TERM FORECAST IS A WINTRY MIX IN WESTERN ND
AND SNOWFALL IN CENTRAL ND. A FREEZING RAIN ADVISORY WILL BE ISSUED
FOR SOUTHWESTERN NORTH DAKOTA...AND A WINTER WEATHER ADVISORY FOR
THE SOUTH CENTRAL.
CURRENTLY...ARCTIC HIGH PRESSURE EXTENDED FROM MANITOBA TO
IOWA...WITH LOW PRESSURE ALONG THE LEE OF THE ROCKIES. TEMPERATURES
HAVE BEEN RISING ACROSS WESTERN AND CENTRAL NORTH DAKOTA EARLY THIS
MORNING. LOWS RANGED FROM 5 TO 20 BELOW ZERO FROM THE TURTLE
MOUNTAINS TO THE JAMES RIVER VALLEY...BUT WERE CURRENTLY AROUND 5
BELOW ZERO. FARTHER WEST TEMPERATURES HAVE BEEN FAIRLY STEADY OR
RISING...WITH TEENS IN THE FAR WEST ALL NIGHT.
WARM ADVECTION FROM THE WEST...ACCOMPANIED BY ISENTROPIC LIFT...WAS
ASSOCIATED WITH A BAND OF LIGHT SNOW THAT EXTENDED FROM WILLISTON
AND STANLEY IN THE NORTHWEST TO GRANT AND SIOUX COUNTIES IN THE
SOUTH CENTRAL PART OF THE STATE. THE LATEST ITERATIONS OF THE
HIGHRES MODELS INDICATE THIS BAND OF LIGHT SNOW
WEAKENING/DISSIPATING AS IT PROGRESSES EASTWARD THIS MORNING.
A SIGNIFICANT UPPER LEVEL SHORTWAVE IS FORECAST TO MOVE EAST ACROSS
IDAHO AND MONTANA THIS MORNING...THEN MOVE SOUTHEAST ACROSS THE
DAKOTAS THIS AFTERNOON AND TONIGHT. PRECIPITATION IS EXPECTED TO
DEVELOP BEFORE NOON IN THE SOUTHWEST AND AROUND NOON IN CENTRAL
NORTH DAKOTA ASSOCIATED WITH THIS SHORTWAVE.
THE 00Z AND 06Z HIGHRES MODELS SUGGEST STRONG WARM ADVECTION
CONTINUING IN THE SOUTHWEST...WITH MAX TEMPERATURES ALOFT AROUND +3
TO +5 C. THUS THE THERMAL PROFILES SUGGEST A MIX OF LIGHT FREEZING
RAIN...SLEET...SNOW...OR RAIN AT TIMES THIS AFTERNOON. AS THE
SHORTWAVE PASSES THROUGH...COLD ADVECTION WILL ENSUE AND
PRECIPITATION WILL LIKELY CHANGE TO LIGHT SNOW THIS EVENING IN
SOUTHWESTERN NORTH DAKOTA.
IN SOUTH CENTRAL NORTH DAKOTA...THE THERMAL PROFILES SUGGEST MAINLY
SNOW...BUT A MIX OF SLEET OR FREEZING RAIN IS POSSIBLE AS WELL -
ESPECIALLY DURING THE AFTERNOON. MODELS ARE NOT IN THE BEST
AGREEMENT REGARDING SNOW AMOUNTS...BUT CONSENSUS SNOW AMOUNTS ARE IN
THE 3-5 INCH RANGE BY DAYBREAK SUNDAY MORNING. THUS CONFIDENT ON AT
LEAST WINTER WEATHER ADVISORY FOR THE SOUTH CENTRAL. SOME OF THE
LATEST ITERATIONS OF THE SHORT TERM MODELS ARE HINTING AT HIGHER
SNOW AMOUNTS...BUT CONFIDENCE IS LOWER - MAINLY BECAUSE IF THERMAL
PROFILES ARE WARMER/COOLER THAN FORECAST THIS WILL IMPACT SNOW
AMOUNTS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 346 AM CST SAT FEB 13 2016
ABOVE NORMAL TEMPERATURES HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC AND INCOMING 06 UTC DETERMINISTIC AND ENSEMBLE SUITES
ARE IN GOOD AGREEMENT ON A BROAD...LOW AMPLITUDE UPPER LEVEL RIDGE
BUILDING ACROSS THE CENTRAL CONUS THROUGHOUT THE EXTENDED FORECAST
PERIOD. THUS...ABOVE NORMAL HIGH TEMPERATURES IN THE 30S AND 40S
ARE EXPECTED OVER MUCH OF WESTERN AND CENTRAL NORTH DAKOTA
THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 701 AM CST SAT FEB 13 2016
A BAND OF LIGHT SNOW WAS OVER NORTHWEST AND CENTRAL NORTH DAKOTA
EARLY THIS MORNING WITH CEILINGS AND VSBYS LOWERING TO MVFR. EXPECT
MVFR CEILINGS TO REMAIN AT CENTRAL ND SITES ONCE THEY ARRIVE. BUT
PERHAPS A PERIOD OF LOW VFR CEILINGS AT KISN AND KDIK 12-18Z
BEFORE LOWERING BACK TO MVFR AFT 18Z SAT. MAIN CONCERN IS LATER ON
SATURDAY 15Z- 23Z IN WESTERN ND WHEN WARM ADVECTION FROM THE WEST
WOULD BRING A WINTRY MIX STARTING WITH SNOW...LEADING TO
SLEET...THEN FREEZING RAIN...BEFORE CHANGING BACK TO SNOW AFT 00Z.
WILL BE ANALYZING LATEST MODELS AND HOPE TO HAVE A HIGHER
CONFIDENCE LEVEL FOR THE 12Z TAF ISSUANCE FOR TIMING AT KISN AND
KDIK.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM CST /5 AM MST/ SUNDAY FOR
NDZ004-005-011>013-019>023-025-034>037-042-045>048-050-051.
FREEZING RAIN ADVISORY UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT
FOR NDZ017-018-031>033-040-041-043-044.
&&
$$
UPDATE...ZH
SHORT TERM...JV
LONG TERM...AYD
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1013 AM EST SAT FEB 13 2016
.SYNOPSIS...
POLAR VORTEX OVR S QUEBEC WILL RAPIDLY LIFT NE BY LATE IN THE
WEEKEND. A DEEPENING UPPER LVL TROF OVER THE CENTRAL CONUS WILL
SPAWN A LOW PRES SYSTEM...WHICH WILL LIKELY TRACK NORTHWARD ACROSS
EASTERN PA ON TUESDAY.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
ARCTIC AIR MASS CONTINUES TO PUSH THROUGH THE REGION TODAY.
TEMPERATURES WILL NOT MOVE TOO MUCH HIGHER THAN CURRENT VALUES.
STRONG NORTHWEST WINDS AND TEMPERATURES IN JUST ABOVE ZERO IN THE
NORTHWESTERN AREAS TO A BALMY MID-TEENS IN THE SOUTHEAST WILL
PROVIDE FOR A VERY COLD DAY. WIND CHILLS BELOW ZERO OVER MOST OF
THE REGION TODAY INTO SUNDAY.
WIND GUSTS OF 25 TO 35 MPH HAVE BEEN OBSERVED SO FAR TODAY. COVER
UP WELL IF OUTDOORS OVER THE NEXT 36 HOURS OF SO.
RADAR AND SATELLITE IMAGERY SHOW HURON CONNECTION SNOW BANDS. ONE
BAND MADE INTO STATE COLLEGE AROUND 9 AM FOR A QUICK COATING. THIS
BAND IS MOVING TO THE SOUTHEAST AND COULD BRING LIGHT
SNOW/FLURRIES TO LOWER SUSQUEHANNA VALLEY LATER THIS MORNING.
MORE FOCUSED SNOW IS OVER SOUTHWEST MOUNTAINS. SNOW IN NORTHWESTER
AREAS HAS BEEN QUITE LIMITED. THE NCAR 3KM EFS AND THE HRRR SEEM
TO FOCUS SNOW IN SOUTHWEST MOUNTAINS AND HAVE LIMITED SNOW IN
THEIR RESPECTIVE FORECASTS. THE AIR IS VERY DRY AND HAS NOT BEEN A
PROLIFIC LAKE AND MOUNTAIN SNOW PRODUCER. HIGH RESOLUTION MODELS
KEEP INDICATING THIS. HRRR AT TIMES SHOWS A POTENTIAL MODEST BAND
IN NORTHWESTERN PA THIS EVENING.
COLD WILL BE THE ISSUE OVER THE ENTIRE REGION. BEST ACCUMULATING
SNOW POTENTIAL IN THE SOUTHWEST MOUNTAINS.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH 7 PM SUNDAY/...
MODELS NOT VERY BIG IN SNOW OVERNIGHT INTO SUNDAY. SOME HINTS OF
SNOW EARLY IN THE HRRR AND SREF IN SW MOUNTAINS. COMBINED WITH THE
FALLING INVERSION HEIGHTS AHEAD OF APPROACHING HIGH...LES AND
MOUNTAIN SNOW THREATS WILL DIMINISH. THE HIGH SHOULD DECOUPLE SOME
AREAS OVERNIGHT AND WITH SNOW COVER A GOOD PERIOD OF RADIATIONAL
COOLING IS POSSIBLE IN CENTRAL AND WESTERN AREAS.
THE MASSIVE 1032 TO 1036 HIGH MOVES OVER THE REGION AND IS PARKED
OVERHEAD BY MIDDAY SUNDAY. THIS SHOULD ENSURE THE WINDS DIE AND
THE WINDCHILL ISSUE DIMINISH. BUT WILL STILL BE A VERY COLD
VALENTINES AT LEAST OUTDOORS.
THE EVENING SHOULD STILL HAVE NEAR IDEAL RADIATIONAL COOLING
CONDITIONS. VERY COLD START TO THE OVERNIGHT PERIOD SUNDAY INTO
MONDAY....BUT THE HIGH MOVES OFF FAST SUNDAY NIGHT. OVERNIGHT LOW
SUNDAY LIKELY WILL BE EARLY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
*IMPACT WEATHER HIGHLIGHTS: POTENTIAL WINTER STORM EARLY NEXT
WEEK.
BULK OF MED RANGE GUIDANCE INDICATES THE LIKELIHOOD OF SOME LGT
SNOW ARRIVING MONDAY...AS SFC HIGH DRIFTS OFF THE COAST AND MILDER
SOUTHERLY FLOW OVERRUNS RETREATING ARCTIC AIR MASS. HOWEVER...THE
BIGGER CONCERN INVOLVES DIGGING UPPER TROF OVR THE MISS VALLEY AND
ASSOC SFC LOW PRESSURE LIFTING UP THE APPALACHIANS. MDL SPREAD
CONTINUES TO NARROW...WITH MOST RUNS TRACKING SFC LOW ACROSS
EASTERN PA TUESDAY. THIS TRACK WOULD CERTAINLY FAVOR RAIN ACROSS
EASTERN PA AND RAIN OR SNOW ACROSS WESTERN PA. GIVEN INHERENT MDL
UNCERTAINTIES THIS FAR OUT...WILL MAINTAIN RAIN/SNOW IN THE FCST
FOR MOST OF CENTRAL PA MON NIGHT-TUES. HAVE RAISED POPS INTO THE
LIKELY CATEGORY BASED ON CONVERGING MDL SOLUTIONS.
WILL ALSO HAVE TO WATCH FOR THE POSSIBILITY OF FLOODING ACROSS
EASTERN PA...GIVEN RAINFALL AND SNOWMELT POTENTIAL. LATEST MDL
ENSEMBLE RIVER FORECASTS USING NAEFS SUGGESTS MINOR FLOODING IS A
POSSIBILITY ACROSS THE LOWER SUSQ VALLEY BY TUES. WPC ALSO HAS
HIGHLIGHTED SE PA FOR A SLIGHT RISK OF FLOODING TUESDAY.
NEAR TO ABOVE NORMAL TEMPS APPEAR LIKELY LATER NEXT WEEK...AS
HEIGHTS ARE FORECAST TO RISE AND A PSBL LOW PRESSURE SYSTEM LIFTS
THROUGH THE GREAT LAKES TO THE WEST OF PA.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
ARCTIC AIR MASS POURING INTO THE REGION EARLY THIS MORNING...
CURRENTLY ACCOMPANIED BY GUSTY NW WINDS OF 15G25KTS. WINDS WILL
PICK UP FURTHER DURING THE DAY...WITH GUSTS APPROACHING
40-45KTS...BEFORE GRADUALLY DIMINISHING TONIGHT.
RADAR AT 11Z SHOWING SCT SHSN ACCOMPANYING ARRIVAL OF ARCTIC AIR
MASS ACROSS WESTERN/CENTRAL MTNS. ARRIVAL OF LOW PWAT AIR MASS
SHOULD CAUSE MOST OF THESE SNOW SHOWERS TO DISSIPATE EARLY IN THE
DAY. SNOW SHOWERS WILL LINGER OVER WARREN COUNTY /WITH POSSIBLE
BRIEF EXCURSIONS TOWARD KBFD/ WITH MORE PERSISTENT SNOW
SHOWERS/BANDS ASSOC WITH LK HURON CONNECTION TO LAST THRU THE DAY
ACROSS THE LAUREL HIGHLANDS /KJST/. RESTRICTIONS WILL PERSIST OVER
WESTERN HIGHER TERRAIN. BUT WITH DOWNSLOPE FLOW KICKING IN FOR
CENTRAL MTNS AND SE...VFR WILL BE THE GENERAL RULE - WITH JUST A
CHANCE FOR SOME SCT SNOW BANDS TO CREEP INTO PORTIONS OF THE
CENTRAL MTNS LATE DAY.
OUTLOOK...
SUN...NO SIG WX EXPECTED.
MON...WIDESPREAD RESTRICTIONS DEVELOP WITH SNOW DEVELOPING.
MON NIGHT AND TUE...SNOW LIKELY NW HALF OF PENN...WITH RAIN AND/OR
SNOW IN THE SE. WIDESPREAD RESTRICTIONS CONTINUE. LLWS POSS SE.
WED...ANOTHER WAVE SLIDES THROUGH KEEPING RESTRICTIONS IN
PLACE ALONG WITH POTENTIAL FOR LIGHT SNOW...ESP OVER THE WEST.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WARNING UNTIL 11 AM EST SUNDAY FOR PAZ004>006-037-
041-042.
WIND CHILL ADVISORY UNTIL 11 AM EST SUNDAY FOR PAZ010>012-017-
018-024-033.
WIND ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR PAZ019-025>028-
034>036-045-046-049>053-056>059-063>066.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO 11 AM EST
SUNDAY FOR PAZ019-025>028-034>036-045-046-049>053-056>059-
063>066.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ024-
033.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...GRUMM
SHORT TERM...GRUMM/FITZGERALD
LONG TERM...FITZGERALD/GARTNER
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
925 AM CST SAT FEB 13 2016
.UPDATE...
FIRST VISIBILITY HAS IMPROVED SOUTH OF A FRONTAL BOUNDARY SO LET
DENSE FOG ADVISORY EXPIRE.
BASED ON 15Z SFC OBS...FRONTAL BOUNDARY LOCATED FROM LA GRANGE TO
SUGAR LAND TO GALVESTON. LATEST 14Z HRRR HAS THIS BOUNDARY FAIRLY
WELL RESOLVED AND BEGINS TO PUSH THE BOUNDARY BACK NORTH LATER
THIS AFTERNOON AND TURNS WINDS TO SE. THERE MAY BE ENOUGH CLOUD
COVER AND COOLER AIR TO KEEP MAX TEMPS IN THE 60S BUT MAY STILL
FEEL HUMID WITH DEWPOINTS IN THE 50S SOUTH OF THE BOUNDARY. MAIN
UPDATES TO THE FORECAST WERE TO ENSURE CONSISTENCY WITH ONGOING
TRENDS AND LATEST SHORT RANGE GUIDANCE. OVERALL NOT A LOT OF
CHANGE FROM THE PREVIOUS UPDATE.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 67 52 71 56 71 / 10 10 20 20 20
HOUSTON (IAH) 68 51 71 58 72 / 10 10 20 30 30
GALVESTON (GLS) 61 56 69 58 68 / 10 10 20 20 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
401 PM EST SAT FEB 13 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 401 PM EST SAT FEB 13 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A DEEP TROF OVER SE CANADA
INTO THE NE CONUS WITH THE CORE OF THE COLDEST AIR WELL E OF HERE
NOW. UPSTREAM...NEXT SHORTWAVE OF INTEREST IS MOVING ACROSS THE NRN
ROCKIES. CLOSER TO HOME...WITH LATEST RAP ANALYSIS SHOWING 850MB
TEMPS ACROSS LAKE SUPERIOR RANGING FROM AROUND -19C W TO -25C E...
LES CONTINUES. HOWEVER...UNDER RISING HEIGHTS/SUBSIDENCE...
INVERSION IS DOWN TO AROUND 3KFT W AND 5KFT E. SO...LES IS LIGHT...
BUT STILL EFFECTIVE AT REDUCING VIS OVER THE E DUE TO SMALL
SNOWFLAKE SIZE. WELL AWAY FROM LAKE EFFECT...IT`S BEEN A MOSTLY
SUNNY DAY OVER SCNTRL UPPER MI.
LINGERING LIGHT LES WILL END FROM W TO E TONIGHT AS SFC HIGH PRES
RIDGE PASSES ACROSS THE FCST AREA. WITH MODERATING AIR MASS
RESULTING IN THE DGZ LIFTING INTO THE SHALLOW CONVECTIVE
LAYER...MIGHT BE ABLE TO FLUFF UP AN INCH OR TWO OF SNOW
ACCUMULATION WHERE STRENGTHENING LAND BREEZES FOCUS CONVERGENCE...
MOST LIKELY IN THE E HALF OF ALGER/NRN SCHOOLCRAFT COUNTIES. RIDGE
WILL ARRIVE OVER WRN UPPER MI EARLY THIS EVENING AND THE E
OVERNIGHT. LOSS OF LAKE EFFECT CLOUDS WITH BACKING WINDS WILL BE
REPLACED BY SOME INCREASE IN HIGH CLOUDS IN WAA PATTERN AHEAD OF
SHORTWAVE MOVING INTO THE NRN/CNTRL PLAINS. THAT SAID...ALL AREAS
WILL SEE AT LEAST A SHORT PERIOD OF VERY GOOD RADIATIONAL COOLING
CONDITIONS. IT STILL APPEARS THE CNTRL FCST AREA WILL HAVE THE
LONGEST PERIOD OF EXCELLENT RADIATIONAL COOLING DUE TO CLEAR SKIES
TO START THE EVENING...LATER ARRIVAL OF HIGH CLOUDS AND LONGER
PERIOD OF LIGHT/CALM WIND. AS WITH PREVIOUS FCSTS...MAINTAINED A MIN
TEMP FCST AT OR BLO THE LOWEST GUIDANCE WITH THE TRADITIONAL COLDEST
SPOTS FALLING TOWARD -20F. MOST IF NOT ALL LOCATIONS WILL FALL BLO
0F.
ON SUN...SHORTWAVE MOVING OUT OVER THE PLAINS TONIGHT WILL TRACK ESE
WITH ASSOCIATED DEEP LAYER FORCING PER QVECTORS AND BEST ISENTROPIC
ASCENT PASSING S OF UPPER MI. MODEL TREND OF RECENT DAYS TO PUSH
FORCING/PCPN FARTHER S HAS HELD UP IN LATEST MODEL RUNS. AS A
RESULT...DO NOT EXPECT ANY -SN ASSOCIATED WITH THIS FEATURE TO REACH
THE FCST AREA SUN. ATTENTION THEN TURNS TO LES OFF LAKE MICHIGAN
UNDER DEVELOPING/INCREASING SOUTHERLY FLOW ON THE BACKSIDE OF
DEPARTING HIGH PRES. 850MB TEMPS AROUND -17C AT 12Z RISE TO AROUND
-14C BY 00Z MON...CERTAINLY LOW ENOUGH TO SUPPORT LES. LARGE SCALE
ANTICYCLONIC FLOW AND INVERSIONS AT 4-5KFT WILL LIMIT INTENSITY OF
LES. IN ADDITION...MOST HIGH RES MODEL GUIDANCE DEPICT THE LES
MOSTLY AS A BAND LIFTING N ON A WIND CONVERGENCE ZONE. WHILE THIS
MAY LEAD TO A BURST OF MDT SNOWFALL...ESPECIALLY WITH DGZ SOLIDLY IN
THE CONVECTIVE LAYER...THE HEAVIER SNOW WOULD NOT LAST LONG. FOR
NOW...EXPECT SNOW ACCUMULATIONS UNDER 1 INCH...BUT NOT OUT OF THE
QUESTION FOR LOCALIZED INCH OR TWO OF SNOW ACCUMULATION IF THE
CONVERGENCE ZONE IS STRONG.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 320 PM EST SAT FEB 13 2016
LONG TERM STARTS 00Z MON WITH A SHORTWAVE NEAR SRN LAKE MICHIGAN
THAT WILL CROSS LAKE HURON BY 12Z MON AND THEN MOVE INTO
QUEBEC...AND ANOTHER SHORTWAVE OVER CENTRAL MN THAT WILL MOVE OVER
OR JUST S OF THE CWA LATE SUN NIGHT INTO MON AFTERNOON...AND YET
ANOTHER SHORTWAVE WILL FOLLOW THE SECOND BY ABOUT 12 HOURS. NOT
REALLY LOOKING FOR A LOT OF SYNOPTIC QPF...BUT THE FORCING/MOISTURE
WILL ENHANCE LES OFF LAKE MICHIGAN IN THE SLY FLOW AHEAD OF THE
ACCOMPANYING SFC TROUGH. SLY WIND LAKE EFFECT IS ALWAYS TRICKY...BUT
LOOKS LIKE IT SHOULD START UP AROUND 00Z MON AND REACH A PEAK
BETWEEN 06Z AND 18Z MON WHILE SHIFTING E AND ENDING BEFORE 00Z TUE.
AT THIS POINT...IT LOOKS LIKE THE MOST SNOW WILL FALL ACROSS
MENOMINEE...DELTA...AND SCHOOLCRAFT COUNTIES...AND POSSIBLY INTO
COUNTIES JUST N OF THOSE. THINK WITH S WINDS...THINK MENOMINEE
COUNTY SEEING MUCH LES IS NOT AS LIKELY. OVERALL...ONLY EXPECTING 2
TO MAYBE 3 INCHES IN THESE AREAS. ELSEWHERE...AROUND AN INCH OR LESS.
MAY SEE SOME LIGHT LES OVER W WIND SNOWBELTS MON NIGHT INTO TUE
MORNING AS 850MB TEMPS WILL BE MARGINAL BUT ADDITIONAL SHORTWAVE
WILL PROVIDE SOME ENHANCEMENT. NOT LOOKING AT SIGNIFICANT AMOUNTS.
SFC TROUGH MOVES THROUGH TUE AHEAD OF AN UPPER WAVE. THIS TURNS
WINDS OUT OF THE NW-NNW BY TUE AFTERNOON/EVENING AND DROPS 850MB
TEMPS TO AROUND-15Z BY 00Z WED AND -19C BY 12Z WED. A SFC RIDGE
MOVES THROUGH BY 00Z THU...ENDING MOST OR ALL LES. NOT EXPECTING
SIGNIFICANT SNOWFALL AMOUNTS GIVEN CHANGING WIND DIRECTIONS AND
QUICK ENTRANCE OF THE RIDGE.
COULD SEE A MORE POTENT SYSTEM LATE IN THE WEEK...WITH THE
POSSIBILITY OF SNOW...RAIN...AND FREEZING RAIN. HOWEVER...CONFIDENCE
EVEN IN THE GENERAL STRENGTH/TRACK OF THE SYSTEM IS LOW AS MODELS
VARY FROM RUN TO RUN AND DISAGREE MODEL TO MODEL. CERTAINLY LOOKS
LIKE A WARMUP IS IN STORE FOR AT LEAST THU NIGHT AND FRI...BUT CAN
NOT SAY MUCH ELSE WITH CONFIDENCE. MAINLY WENT WITH A WINTRY MIX OF
PRECIP IN THE FORECAST...WITH CONSENSUS POPS FIELDS OTHERWISE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1244 PM EST SAT FEB 13 2016
WITH WINDS BACKING AS HIGH PRES MOVES E...CROSSING UPPER MI
TONIGHT...LINGERING LAKE EFFECT SNOW SHOWERS AFFECTING KCMX WILL END
TONIGHT. UNTIL THEN...EXPECT IFR VIS TO PREVAIL THIS AFTN.
HOWEVER...AS IS TYPICAL FOR LAKE EFFECT...CONDITIONS WILL BE QUITE
VARIABLE AT TIMES...RANGING FROM BRIEF LIFR TO BRIEF MVFR. EXPECT
IMPROVEMENT TO MVFR AT KCMX THIS EVENING...THEN VFR OVERNIGHT. AT
KIWD...LAST OF THE STRATOCU/MVFR CIGS OFF THE LAKE SHOULD EXIT
WITHIN THE NEXT HR OR SO...LEAVING VFR CONDITIONS TO PREVAIL THRU
THE REMAINDER OF THE FCST PERIOD. AT KSAW...THERE MAY BE OCNL MVFR
CIGS THIS AFTN. OTHERWISE...VFR CONDITIONS WILL BE THE RULE THRU THE
FCST PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 401 PM EST SAT FEB 13 2016
AS HIGH PRES RIDGE PASSES ACROSS LAKE SUPERIOR TONIGHT...WINDS WILL
DIMINISH AND BECOME LIGHT UNDER 15KT FOR A TIME. ONCE THIS HIGH
SHIFTS E OF THE AREA...S WINDS WILL INCREASE UP TO 25-30KT SUN INTO
MON MORNING UNDER THE TIGHTENING PRES GRADIENT BETWEEN THE DEPARTING
HIGH AND AN APPROACHING LOW PRES TROF IN THE PLAINS. THERE COULD BE
A FEW GALE FORCE GUSTS SUN NIGHT OVER THE E HALF OF THE LAKE.
ALTHOUGH WINDS WILL DIMINISH LATER MON...ANOTHER ROUND OF STRONG NNW
WINDS UP TO 30KT WILL DEVELOP TUE/TUE NIGHT FOLLOWING A COLD FRONTAL
PASSAGE. NOT OUT OF THE QUESTION THERE COULD BE A FEW GALE FORCE
GUSTS. WINDS WILL THEN DIMINISH WED WITH ARRIVAL OF ANOTHER HIGH
PRES RIDGE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 6 PM EST THIS EVENING FOR MIZ006-
007-085.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 7 PM EST THIS EVENING FOR
LSZ265>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
328 PM CST SAT FEB 13 2016
.DISCUSSION...
Issued at 327 PM CST SAT FEB 13 2016
Main forecast challenges deal with weather type and headlines. The
forecast area is really being split by wintry weather, both
spatially and temporally, with snowfall in our northeast and light
freezing drizzle in our south. The snowfall will likely start earlier
(late this evening) than the freezing drizzle, which may hold off
unto closer to sunrise. Strong isentropic ascent will eventually
saturate the lowest several thousand feet of the atmosphere in north
central to northeastern Missouri. Have delayed onset of snow several
hours based on forecast soundings,the large temperature/ dewpoint
depressions on surface observations and the relatively high cloud
bases. Forecast soundings for the Kirksville area saturate around
midnight or perhaps a little later. Have waited until then to
increase PoPs into the likely range. Snow amounts in our northeastern
zones are still expected to be in the 1" to as much as 3" range in
Schuyler County. After coordination with neighbors, have issued a
winter weather advisory for our extreme northeastern counties,
including the Kirksville area.
The other aspect of this wintry episode is the potential for
freezing drizzle in the southern half of the forecast area.
Confidence in this is quite a bit lower than with the snowfall in
the northeast. First, the lowest several thousand feet never really
saturate. Second, by the time saturation begins to lower, the warm
front lifts through, warms the surface above freezing and desaturates
the sounding aloft. So there really only looks like a marginal
potential for several hours when lift is maximized coincident with
the greatest amount of saturation. This seems to be around the 12Z
time frame +/- an hour or two. However, freezing drizzle can have a
major impact on travel as it can be deceptive in it`s ability to
slicken roads. So it`ll be important for people who have to travel
Sunday morning to understand that roads may be slick. But for now,
confidence just isn`t high enough to issue an advisory at this time.
Another clipper system will move through Monday night/ Tuesday
morning. Forecast soundings show the lowest several thousand feet to
be above freezing, even all the way into the northeastern portions of
the forecast area. So for snow, the wave should have little impact
with regards to wintry weather in the forecast area and we should see
just rain or perhaps a rain/snow mix in our northern zones.
The rest of the forecast looks quiet regarding precipitation. An
upper level ridge will spread east with low level flow out of the
south. This will help temperatures soar to well above normal levels
by Thursday into Friday. Highs may be in the 70s in parts of the
forecast area Thursday and potentially into Friday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1118 AM CST SAT FEB 13 2016
VFR conditions with ceilings between 5 and 8 thousand feet are
expected through the rest of the afternoon and into the overnight.
Late tonight, ceilings are expected to lower to MVFR and possibly
into the 1500 to 2000 ft range. There is also a chance for light
freezing drizzle across eastern Kansas and western Missouri late
tonight and early tomorrow morning. The most likely timing for this
seems to be centered around 12Z give or take a few hours.
Temperatures are expected to warm above freezing late Sunday morning
with lower levels drying out, ending the potential for freezing
drizzle.
&&
.EAX Watches/Warnings/Advisories...
KS...NONE.
MO...Winter Weather Advisory from 9 PM this evening to 6 PM CST
Sunday for MOZ008-017-025-033.
&&
$$
DISCUSSION...CDB
AVIATION...CDB
[top]
Area Forecast Discussion
National Weather Service SPRINGFIELD MO
244 PM CST SAT FEB 13 2016
...A Light Wintry Mix Late Tonight into Early on Sunday...Much
Warmer Weather Returns Next Week...
.SHORT TERM...(This Evening through Sunday)
Issued at 0217 PM CST SAT FEB 13 2016
Cold and dry air has invaded much of the Missouri Ozarks region this
afternoon. There are some areas across central Missouri that has
barely reached 20 degrees. The main story for tonight into early
tomorrow will be the threat of a light wintry mix and freezing
drizzle. The latest Hi-Res forecast models all indicate very light
precip to begin to develop between midnight and 3 am across
western and southern Missouri. The latest RUC and HRRR even shows
some convective like precip which indicates pockets of sleet possible.
The overall message for late tonight into tomorrow morning is we
are expecting only very light amounts of a light wintry mix but
could be impacts on roads and travel in the morning. Ground and
road temperatures have had time to cool down over the past 24
hours. The freezing line will settle somewhere near the Missouri
and Kansas border tonight before it begins to retreat eastward
during the morning hours. There will be very light precip falling
across the Missouri Ozarks with the better potential for higher
amounts across the eastern Ozarks. Freezing drizzle and some light
sleet is expected across the western half of the area and a wintry
mix with some light snow is expected across the eastern half of
the area early on. This will slowly transition to just a cold
light rain or drizzle late tomorrow morning into the early
afternoon from west to east.
We will issue a winter weather advisory for light amounts and
possible travel impacts in the morning. Like what we saw a few
weeks ago...it does not take much freezing drizzle to cause big
travel problems in the Ozarks region. All areas in the advisory
area can expect a very light glaze of ice possible. A dusting of
light sleet or light snow can be expected east of Highway 65 with
up to an inch of snow possible from the Highway 63 corridor and
eastward. Most area will warm up above freezing by Sunday
afternoon with some areas out across far western Missouri near 50.
.LONG TERM...(Sunday Night through Saturday)
Issued at 0217 PM CST SAT FEB 13 2016
There may be some fog developing late Sunday night into Monday
morning. This will need to be watched because temperatures again
may be around or slightly below freezing. The best potential for
fog will be along and south of the I-44 corridor across southern
Missouri.
Milder temperatures return on Monday. A quick moving upper level
system across the Midwest on Tuesday may bring a few more clouds
and a slight chance of showers across central Missouri and the
eastern Ozarks. Decent upper Level ridging will develop across
the central U.S. for the middle and end of next week. This will
allow for way above average temperatures for the region. Highs
will be in the 60s and possible lower 70s. A preview of Spring is
coming next week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1156 AM CST SAT FEB 13 2016
An upper level disturbance will slide southeast across the region
from late tonight into Sunday. This system will bring a variety of
aviation impacts.
Ceilings will lower starting late tonight with MVFR expected
during the predawn hours. We are also expecting a light wintry mix
of precipitation to develop late tonight, however precipitation
onset time remains in question due to a very dry airmass which is
currently in place. We have therefore handled this uncertainty
with TEMPO groups.
Low level wind shear conditions are also expected from late
tonight into early Sunday morning.
By sunrise, precipitation should be ongoing over most areas with
freezing drizzle being the main precipitation type. Precipitation
will begin to diminish around Joplin and then Springfield by late
morning with temperatures warming to around the freezing mark by
midday. Ceilings will remain in the MVFR category.
&&
.SGF Watches/Warnings/Advisories...
MO...Winter Weather Advisory from 3 AM to noon CST Sunday for
MOZ055>058-066>071-077>083-088>098-101>106.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Schaumann
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1230 PM CST SAT FEB 13 2016
.UPDATE...
ISSUED AT 1215 PM CST SAT FEB 13 2016
ADDED A FREEZING RAIN ADVISORY FOR WILLIAMS AND DIVIDE COUNTY
THROUGH 00Z TONIGHT AND EXPANDED THE WINTER WEATHER ADVISORY INTO
BURKE...MOUNTRAIL...AND RENVILLE COUNTIES WITH THIS UPDATE.
LATEST OBSERVATIONS OUT OF NORTHEASTERN MONTANA AND FORECAST
SOUNDINGS NEAR WILLISTON SUPPORT A PERIOD OF FREEZING RAIN AND
SNOW MIX IN THE NORTHWEST THROUGH LATE AFTERNOON. BY
EVENING...PRECIPITATION SHOULD TRANSITION TO ALL SNOW. THE
FORECAST APPEARS ON TRACK FOR THE REST OF THE AREA.
UPDATE ISSUED AT 947 AM CST SAT FEB 13 2016
NO SIGNIFICANT CHANGES WERE NEEDED FOR THIS UPDATE. DID INCREASE
PRECIPITATION CHANCES OVER THE WEST AND CENTRAL THROUGH 18Z...AS
MULTIPLE OBSERVATIONS ARE COMING IN WITH LIGHT SNOW WHERE THERE
HAVE BEEN LITTLE TO NO RADAR RETURNS. THINKING REMAINS THE SAME ON
WINTER WEATHER HEADLINES AS WE ENTER A HOLDING PATTERN...WITH LOW
PRESSURE NOW DEVELOPING OVER SOUTHERN SASKATCHEWAN AND NORTHERN
WYOMING.
UPDATE ISSUED AT 701 AM CST SAT FEB 13 2016
EXPANDED THE WINTER WEATHER ADVISORY INTO THE NORTH CENTRAL AND
TURTLE MOUNTAINS AREA FOR THIS AFTERNOON THROUGH TONIGHT WITH THIS
UPDATE.
THE FULL 00 AND 06 UTC DETERMINISTIC AND ENSEMBLE SUITES AND THE
08-11 UTC HRRR AND RAP ITERATIONS ALL SUPPORT THE POTENTIAL FOR
MODERATE SNOWFALL ACCUMULATIONS ACROSS THE NORTH CENTRAL AND
TURTLE MOUNTAINS AREA THIS AFTERNOON THROUGH TONIGHT. OVERALL...A
CONSENSUS OF THESE SOLUTIONS SUPPORTS GREATER QPF THAN THE
PREVIOUS FORECAST OVER MOST OF THE CWA THIS AFTERNOON THROUGH
TONIGHT...LEADING TO GREATER SNOWFALL TOTALS. OBSERVED TRENDS
ACROSS MONTANA THIS MORNING AND THE 12 UTC SUITE WILL HAVE TO BE
CLOSELY EVALUATED AS SOME LOCATIONS ACROSS CENTRAL NORTH DAKOTA
HAVE THE POTENTIAL TO APPROACH WARNING LEVEL SNOWFALL AS DEPICTED
IN 00 AND 06 UTC SUITES. HEAVY SNOWFALL RATES ARE POSSIBLE GIVEN
STEEP MID LEVEL LAPSE RATES ASSOCIATED WITH THE POTENT SHORTWAVE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CST SAT FEB 13 2016
THE FOCUS OF THE SHORT TERM FORECAST IS A WINTRY MIX IN WESTERN ND
AND SNOWFALL IN CENTRAL ND. A FREEZING RAIN ADVISORY WILL BE ISSUED
FOR SOUTHWESTERN NORTH DAKOTA...AND A WINTER WEATHER ADVISORY FOR
THE SOUTH CENTRAL.
CURRENTLY...ARCTIC HIGH PRESSURE EXTENDED FROM MANITOBA TO
IOWA...WITH LOW PRESSURE ALONG THE LEE OF THE ROCKIES. TEMPERATURES
HAVE BEEN RISING ACROSS WESTERN AND CENTRAL NORTH DAKOTA EARLY THIS
MORNING. LOWS RANGED FROM 5 TO 20 BELOW ZERO FROM THE TURTLE
MOUNTAINS TO THE JAMES RIVER VALLEY...BUT WERE CURRENTLY AROUND 5
BELOW ZERO. FARTHER WEST TEMPERATURES HAVE BEEN FAIRLY STEADY OR
RISING...WITH TEENS IN THE FAR WEST ALL NIGHT.
WARM ADVECTION FROM THE WEST...ACCOMPANIED BY ISENTROPIC LIFT...WAS
ASSOCIATED WITH A BAND OF LIGHT SNOW THAT EXTENDED FROM WILLISTON
AND STANLEY IN THE NORTHWEST TO GRANT AND SIOUX COUNTIES IN THE
SOUTH CENTRAL PART OF THE STATE. THE LATEST ITERATIONS OF THE
HIGHRES MODELS INDICATE THIS BAND OF LIGHT SNOW
WEAKENING/DISSIPATING AS IT PROGRESSES EASTWARD THIS MORNING.
A SIGNIFICANT UPPER LEVEL SHORTWAVE IS FORECAST TO MOVE EAST ACROSS
IDAHO AND MONTANA THIS MORNING...THEN MOVE SOUTHEAST ACROSS THE
DAKOTAS THIS AFTERNOON AND TONIGHT. PRECIPITATION IS EXPECTED TO
DEVELOP BEFORE NOON IN THE SOUTHWEST AND AROUND NOON IN CENTRAL
NORTH DAKOTA ASSOCIATED WITH THIS SHORTWAVE.
THE 00Z AND 06Z HIGHRES MODELS SUGGEST STRONG WARM ADVECTION
CONTINUING IN THE SOUTHWEST...WITH MAX TEMPERATURES ALOFT AROUND +3
TO +5 C. THUS THE THERMAL PROFILES SUGGEST A MIX OF LIGHT FREEZING
RAIN...SLEET...SNOW...OR RAIN AT TIMES THIS AFTERNOON. AS THE
SHORTWAVE PASSES THROUGH...COLD ADVECTION WILL ENSUE AND
PRECIPITATION WILL LIKELY CHANGE TO LIGHT SNOW THIS EVENING IN
SOUTHWESTERN NORTH DAKOTA.
IN SOUTH CENTRAL NORTH DAKOTA...THE THERMAL PROFILES SUGGEST MAINLY
SNOW...BUT A MIX OF SLEET OR FREEZING RAIN IS POSSIBLE AS WELL -
ESPECIALLY DURING THE AFTERNOON. MODELS ARE NOT IN THE BEST
AGREEMENT REGARDING SNOW AMOUNTS...BUT CONSENSUS SNOW AMOUNTS ARE IN
THE 3-5 INCH RANGE BY DAYBREAK SUNDAY MORNING. THUS CONFIDENT ON AT
LEAST WINTER WEATHER ADVISORY FOR THE SOUTH CENTRAL. SOME OF THE
LATEST ITERATIONS OF THE SHORT TERM MODELS ARE HINTING AT HIGHER
SNOW AMOUNTS...BUT CONFIDENCE IS LOWER - MAINLY BECAUSE IF THERMAL
PROFILES ARE WARMER/COOLER THAN FORECAST THIS WILL IMPACT SNOW
AMOUNTS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 346 AM CST SAT FEB 13 2016
ABOVE NORMAL TEMPERATURES HIGHLIGHT THE EXTENDED FORECAST.
THE 00 UTC AND INCOMING 06 UTC DETERMINISTIC AND ENSEMBLE SUITES
ARE IN GOOD AGREEMENT ON A BROAD...LOW AMPLITUDE UPPER LEVEL RIDGE
BUILDING ACROSS THE CENTRAL CONUS THROUGHOUT THE EXTENDED FORECAST
PERIOD. THUS...ABOVE NORMAL HIGH TEMPERATURES IN THE 30S AND 40S
ARE EXPECTED OVER MUCH OF WESTERN AND CENTRAL NORTH DAKOTA
THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1215 PM CST SAT FEB 13 2016
FAST MOVING LOW PRESSURE WAS DEVELOPING OVER SOUTHEASTERN
MONTANA. THIS SYSTEM WILL BRING FROZEN PRECIPITATION TO MUCH OF
THE WESTERN AND CENTRAL PARTS OF NORTH DAKOTA THROUGH THE
AFTERNOON AND OVERNIGHT HOURS. PRECIPITATION WILL BEGIN AS A MIX
OF RAIN...FREEZING...AND SNOW IN THE WEST THIS
AFTERNOON...EVENTUALLY TRANSISTIONING TO ALL SNOW BY TONIGHT. MFVR
CEILINGS AND VISIBILITES WILL BE COMMON ACROSS ALL SITES...WITH
PERIODS OF IFR/LIFR CONDITIONS POSSIBLE WITHIN ANY HEAVIER SNOW
BANDS. WINDS OF 15-20 KNOTS WILL GENERALLY COME FROM THE SOUTH
THIS AFTERNOON...TRANSITIONING WEST/NORTHWESTERLY BY THE OVERNIGHT
HOURS. PRECIPITATION WILL BEGIN TO DIMINISH EARLY SUNDAY MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM CST /5 AM MST/ SUNDAY FOR
NDZ002>005-010>013-019>023-025-034>037-042-045>048-050-051.
FREEZING RAIN ADVISORY UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT
FOR NDZ017-018-031>033-040-041-043-044.
FREEZING RAIN ADVISORY UNTIL 6 PM CST THIS EVENING FOR NDZ001-
009.
&&
$$
UPDATE...ZH
SHORT TERM...JV
LONG TERM...AYD
AVIATION...ZH
AREA FORECAST DISCUSSION
NWS NORMAN OK
1207 PM CST SAT FEB 13 2016
.AVIATION...
GUSTY SOUTHEAST WINDS WILL PREVAIL THROUGH THE EVENING
WITH A FEW HIGH CLOUDS. MOISTURE RETURN LATE THIS EVENING
AND OVERNIGHT WILL RESULT IN AT LEAST MVFR CEILINGS...ESPECIALLY
AFTER 6Z. A LITTLE UNSURE HOW FAR LOW CEILINGS WILL EXTEND IN
WEST CENTRAL AND NORTHWEST OKLAHOMA. A FRONT WILL MOVE ACROSS
ALL TAF SITES BY 18Z SUNDAY WITH NORTH TO NORTHWEST WINDS BEHIND
THE FRONT. IFR CEILINGS MAY DEVELOP JUST AHEAD AND SHORTLY
BEHIND THE FRONTAL PASSAGE. WILL ALSO MENTION THE POTENTIAL FOR
FOG WITH BETTER CHANCES IN AND AROUND OKC/OUN.
&&
.PREV DISCUSSION... /ISSUED 1050 AM CST SAT FEB 13 2016/
DISCUSSION...
CIRCULATION FROM COLD HIGH PRESSURE OVER IOWA WILL KEEP NORTH
CENTRAL AND CENTRAL OKLAHOMA THE COOLEST THIS AFTERNOON.
SURFACE WINDS HAVE ALREADY SHIFTED TO A EAST AND SOUTHEAST
DIRECTION THIS MORNING...AND SHOULD KEEP A SOUTHEAST COMPONENT
DURING THE AFTERNOON. THE HRRR AND RAP APPEAR A LITTLE WARM WITH
HIGHS THIS AFTERNOON (SLIGHTLY VEERED FLOW)...BUT HAVE TRENDED A
LITTLE WARMER IN SOME AREAS.
PREV DISCUSSION... /ISSUED 604 AM CST SAT FEB 13 2016/
DISCUSSION...
AVIATION...
EAST WINDS WILL TURN SOUTH TODAY AND INCREASE AHEAD OF A SURFACE
TROUGH. MVFR CEILINGS ARE EXPECTED TO MOVE NORTHWARD TONIGHT FROM
TEXAS WHERE LOWER-LEVEL MOISTURE IS HIGHER.
PREV DISCUSSION... /ISSUED 324 AM CST SAT FEB 13 2016/
DISCUSSION...
SLIGHTLY COOLER WEATHER IS EXPECTED TODAY IN THE WAKE OF THE
AIRMASS THAT IS DRIFTING OFF TO THE NORTHEAST OF OKLAHOMA.
HOWEVER, THE SUNDAY AND NEXT WEEK WILL SEE INCREASING WARMING TO
THE POINT OF HOT BY THE LATER PART OF THE WEEK. BEFORE THAT, RAIN
CHANCES CROSS THROUGH EASTERN AND SOUTHEASTERN OKLAHOMA SUNDAY AND
EARLY MONDAY WHEN SEVERAL SURFACE TROUGHS AND WEAK UPPER WAVES
PASS BY. BEYOND THEN, NO PRECIPITATION IS EXPECTED THROUGH NEXT
WEEK. THE MAIN WEATHER IMPACT WILL LIKELY BE INCREASED FIRE
WEATHER POTENTIAL, ESPECIALLY THURSDAY WHEN GUSTY SOUTHWEST WINDS
AND TEMPERATURES IN THE 70S AND 80S ARE EXPECTED. A WEAK FRONT IN
THE WEEKEND WILL BRING LOWER, BUT STILL SEASONABLY HIGH
TEMPERATURES.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 53 43 62 38 / 0 10 10 10
HOBART OK 55 44 63 36 / 0 0 0 0
WICHITA FALLS TX 62 48 68 40 / 0 0 0 10
GAGE OK 55 34 60 29 / 0 0 0 10
PONCA CITY OK 45 34 58 33 / 0 10 10 0
DURANT OK 56 46 62 44 / 0 10 20 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
1050 AM CST SAT FEB 13 2016
.DISCUSSION...
CIRCULATION FROM COLD HIGH PRESSURE OVER IOWA WILL KEEP NORTH
CENTRAL AND CENTRAL OKLAHOMA THE COOLEST THIS AFTERNOON.
SURFACE WINDS HAVE ALREADY SHIFTED TO A EAST AND SOUTHEAST
DIRECTION THIS MORNING...AND SHOULD KEEP A SOUTHEAST COMPONENT
DURING THE AFTERNOON. THE HRRR AND RAP APPEAR A LITTLE WARM WITH
HIGHS THIS AFTERNOON (SLIGHTLY VEERED FLOW)...BUT HAVE TRENDED A
LITTLE WARMER IN SOME AREAS.
&&
.PREV DISCUSSION... /ISSUED 604 AM CST SAT FEB 13 2016/
DISCUSSION...
AVIATION...
EAST WINDS WILL TURN SOUTH TODAY AND INCREASE AHEAD OF A SURFACE
TROUGH. MVFR CEILINGS ARE EXPECTED TO MOVE NORTHWARD TONIGHT FROM
TEXAS WHERE LOWER-LEVEL MOISTURE IS HIGHER.
PREV DISCUSSION... /ISSUED 324 AM CST SAT FEB 13 2016/
DISCUSSION...
SLIGHTLY COOLER WEATHER IS EXPECTED TODAY IN THE WAKE OF THE
AIRMASS THAT IS DRIFTING OFF TO THE NORTHEAST OF OKLAHOMA.
HOWEVER, THE SUNDAY AND NEXT WEEK WILL SEE INCREASING WARMING TO
THE POINT OF HOT BY THE LATER PART OF THE WEEK. BEFORE THAT, RAIN
CHANCES CROSS THROUGH EASTERN AND SOUTHEASTERN OKLAHOMA SUNDAY AND
EARLY MONDAY WHEN SEVERAL SURFACE TROUGHS AND WEAK UPPER WAVES
PASS BY. BEYOND THEN, NO PRECIPITATION IS EXPECTED THROUGH NEXT
WEEK. THE MAIN WEATHER IMPACT WILL LIKELY BE INCREASED FIRE
WEATHER POTENTIAL, ESPECIALLY THURSDAY WHEN GUSTY SOUTHWEST WINDS
AND TEMPERATURES IN THE 70S AND 80S ARE EXPECTED. A WEAK FRONT IN
THE WEEKEND WILL BRING LOWER, BUT STILL SEASONABLY HIGH
TEMPERATURES.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 53 43 62 38 / 0 10 10 10
HOBART OK 55 44 63 36 / 0 0 0 0
WICHITA FALLS TX 62 48 68 40 / 0 0 0 10
GAGE OK 55 34 60 29 / 0 0 0 10
PONCA CITY OK 45 34 58 33 / 0 10 10 0
DURANT OK 56 46 62 44 / 0 10 20 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PORTLAND OR
201 PM PST SAT FEB 13 2016
.SYNOPSIS...A STRONG WARM FRONT IS SPREADING RAIN AND BREEZY
CONDITIONS INTO SOUTHWEST WASHINGTON AND NORTHWEST OREGON THIS
AFTERNOON. RAIN WILL BECOME HEAVY AT TIMES...ESPECIALLY ALONG THE
COAST AND IN THE HIGHER TERRAIN. SNOW LEVELS ARE STARTING OFF NEAR
THE CASCADE PASSES...BUT ARE EXPECTED TO RISE TONIGHT AS WARMER AIR
MOVES IN. THE FRONTAL ZONE WILL LINGER OVER THE AREA SUNDAY...THEN
LIFT NORTH SUNDAY NIGHT AND MONDAY FOR DECREASING RAIN. HIGH PRESSURE
WILL BRING DRIER WEATHER LATER MONDAY INTO TUESDAY...ESPECIALLY FOR
SOUTHERN ZONES. AN UPPER LEVEL TROUGH IS EXPECTED TO BRING COOLER AND
SHOWERY WEATHER LATER WEDNESDAY INTO THURSDAY...WITH SNOW POSSIBLE
FOR THE CASCADE PASSES AND ABOVE.
&&
.SHORT TERM...TONIGHT THROUGH TUESDAY...NWS DOPPLER RADAR SHOWS RAIN
SPREADING EASTWARD ACROSS THE FORECAST AREA THIS AFTERNOON...MAINLY
NORTH OF A LINCOLN CITY TO SALEM LINE. THIS IS ASSOCIATED WITH A
POTENT PACIFIC FRONTAL SYSTEM WHICH WILL PUSH A WARM FRONT ACROSS THE
FORECAST AREA TONIGHT. LOOKING AT THE BIGGER PICTURE...THIS FRONTAL
SYSTEM HAS A DECENT MOISTURE TAP ALL THE WAY BACK TO THE SUBTROPICAL
LATITUDES NEAR THE DATELINE. BLENDED PRECIPITABLE WATER VALUES SHOW
1.2 INCH OR HIGHER WITHIN THIS MOISTURE PLUME AS FAR EAST AS 130W.
12Z NAM/GFS SUGGEST PW VALUES AROUND 1 INCH REACHING OUR FORECAST
AREA THIS EVENING...COUPLED WITH OROGRAPHICALLY FAVORABLE W-SW WINDS
OF 40-50 KT AT 850 MB. THIS SHOULD YIELD A PERIOD OF FAIRLY HEAVY
RAINFALL FOR THE COAST AND HIGHER TERRAIN... ESPECIALLY NORTHERN
ZONES WHERE 2-4 INCHES OF RAIN ARE POSSIBLE BY SUNDAY. INLAND VALLEYS
WILL SEE LESS...RANGING FROM AROUND 0.50 INCH SOUTH OF SALEM TO
AROUND 1 INCH IN THE PDX METRO. 12Z GFS SHOWS THE BEST ISENTROPIC
LIFT MOVING THROUGH BY MIDNIGHT TONIGHT. AFTER THAT FORCING MOVES
EAST...THE WILLAMETTE VALLEY WILL LIKELY BE HEAVILY RAIN SHADOWED IN
LOW-LEVEL WESTERLY FLOW LATER TONIGHT INTO SUNDAY.
SNOW AMOUNTS REMAIN A CHALLENGING FORECAST FOR THE CASCADES WITH THIS
SYSTEM. OFTEN TIMES...LEFTOVER COLD AIR...WET-BULB EFFECTS AND LATENT
HEAT PROCESSES WILL HOLD ON TO LOWER SNOW LEVELS MOUNT HOOD NORTHWARD
A BIT LONGER THAN MODELS EXPECT. HOWEVER THIS DOES NOT APPEAR TO BE
ONE OF THOSE SCENARIOS AS FAIRLY STRONG WARM ADVECTION WILL BE MOVING
IN ON THE 40-50 KT W-SW 850-700 MB FLOW LATER TONIGHT. SOME WET SNOW
IS POSSIBLE FOR THE PASSES THIS AFTERNOON INTO THIS EVENING...BUT
ACCUMULATIONS SHOULD BE LIGHT. HIGHER SKI RESORT ELEVATIONS LOOK MORE
LIKELY TO SEE 5-10 INCHES BEFORE SNOW LEVELS SKYROCKET TO 7000 FEET
SUNDAY MORNING. IF SNOW LEVELS REMAIN LOWER THAN EXPECTED...SNOW
ACCUMULATIONS COULD BE SUBSTANTIALLY HIGHER GIVEN THE HEAVY QPF THAT
IS EXPECTED. HOWEVER...AM FAIRLY CONFIDENT THAT THE CHANGEOVER WILL
BE QUICK LATER TONIGHT OR SUNDAY MORNING. NOT EXPECTING TO CHANGE
MUCH WITH THE EXISTING WINTER WX ADVISORY FOR SNOW...THOUGH WILL
PROBABLY ADD SOME WORDING TO SUGGEST THE GREATEST ACCUMULATIONS WILL
LIKELY REMAIN UP IN THE HIGHER SKI RESORT ELEVATIONS.
THE HEAVY RAINFALL MAY CAUSE SOME MINOR HYDROLOGIC ISSUES...MAINLY
FOR CREEKS AND SMALL STREAMS DRAINING OUT OF THE COAST RANGE AND
CASCADES. THE GRAYS RIVER IN WAHKIAKUM COUNTY IS NOTORIOUSLY FAST-
RESPONDING...SO 2-4 INCHES OF RAIN IN A 24 HOUR PERIOD MAY PUSH IT
CLOSE TO BANKFULL. WILL BE KEEPING A CLOSE EYE ON THIS RIVER AMONG
OTHERS AS RAIN INCREASES LATER TODAY AND TONIGHT...BUT SIGNIFICANT
MAIN STEM RIVER FLOODING IS NOT EXPECTED AT THIS TIME.
UPPER LEVEL RIDGING WILL BEGIN BUILDING IN FROM THE SW SUNDAY...BUT
WEAK SHORTWAVES WILL LIKELY RIDE OVER THE TOP OF THE RIDGE AND REMAIN
INTACT TO KEEP SOME RAIN IN THE PICTURE THROUGH SUN EVENING. DRYING
TREND IS EXPECTED MON/TUE AS THE UPPER RIDGE SHOVES THE MAIN
BAROCLINIC ZONE NORTHWARD INTO WA/BC. SW WA MAY REMAIN CLOSE ENOUGH
TO THE FRONTAL ZONE TO KEEP SOME RAIN OR DRIZZLE AROUND...BUT AREAS
PDX METRO SOUTHWARD SHOULD BE MAINLY DRY MON/TUE. STRENGTHENING
INVERSIONS MAY PROMOTE NIGHT AND MORNING FOG... ESPECIALLY SOUTH OF
SALEM WHERE SKIES HAVE THE BEST CHANCE OF CLEARING. ANY FOG THAT DOES
DEVELOP MAY BE STUBBORN. DID NOT FACTOR THIS INTO MON/TUE MAX TEMP
FORECASTS YET...AS THERE REMAINS A GOOD DEAL OF UNCERTAINTY AS TO IF
AND WHERE FOG WILL DEVELOP. WEAGLE
.LONG TERM...TUESDAY NIGHT THROUGH FRIDAY...THE UPPER RIDGE
RESPONSIBLE FOR THE DRYING TREND MON/TUE WILL SHIFT EAST MIDWEEK...
WITH MODELS SHOWING GOOD CONSENSUS IN BRINGING A WELL DEFINED UPPER
TROUGH INTO THE PAC NW AND POSSIBLY CALIFORNIA WED NIGHT/THU. THIS
WILL CAUSE RAIN CHANCES TO INCREASE LATER WED...WITH COOL AND SHOWERY
WEATHER LINGERING INTO THU. AIR MASS WILL START OUT RATHER WARM WITH
SNOW LEVELS WELL ABOVE THE CASCADE PASSES WED. COLDER AIR WILL MOVE
IN WITH THE UPPER TROUGH...WITH SNOW LEVELS LOWERING TO 3000 TO 3500
FEET IN SHOWERS BY THURSDAY. EXPECT TEMPS TO DROP BACK TO NEAR NORMAL
LATE WEEK AS A RESULT OF THE UPPER TROUGH...POSSIBLY EVEN A LITTLE
BELOW NORMAL. MODELS SHOW DECENT AGREEMENT THAT THIS UPPER TROUGH
WILL BE FOLLOWED BY A MORE PROGRESSIVE FRONTAL SYSTEM FOR MORE RAIN
AND CASCADE SNOW FRI/FRI NIGHT. WEAGLE
&&
.AVIATION...WARM-FRONTAL PRECIP BEGINNING TO SPREAD INTO THE S
WASHINGTON AND N OREGON COAST EARLY THIS AFTERNOON. VFR ACROSS THE
AREA...EXCEPT AREAS OF MVFR ALONG THE COAST. FLIGHT CONDITIONS
ALONG THE COAST DETERIORATE THROUGH THE AFTERNOON AND EARLY
EVENING...DROPPING TO IFR BY 00Z SUN. MVFR COVERAGE TO INCREASE
OVER THE INTERIOR LOWLANDS AFTER 00Z SUN. INTERIOR VALLEYS MAY
SEE MORE VFR OVERNIGHT THROUGH SUN DUE TO RAIN-SHADOW EFFECTS.
STRONG 850 MB WEST FLOW WILL RESULT IN ENHANCED OROGRAPHIC LIFT
OVER THE HIGHER TERRAIN...RESULTING IN MOUNTAIN OBSCUREMENT AND
IFR OR WORSE FLIGHT CONDITIONS.
KPDX AND APPROACHES...VFR AT 21Z. CIGS WILL CONTINUE TO LOWER
THROUGH THE AFTERNOON AND EARLY EVENING...WITH MVFR CONDITIONS
LIKELY AFTER 02Z SUN...ESPECIALLY ALONG WRN APPROACHES. S WIND
SHOULD ALLOW FOR LONGER-DURATION VFR CONDITIONS OVERNIGHT THROUGH
SUN. WEISHAAR
&&
.MARINE...WIND GUSTS ON THE EDGE OF GALE FORCE OVER THE NRN OUTER
WATERS EARLY THIS AFTERNOON. THE 14Z RUC RUN WAS A LITTLE STRONGER
COMPARED TO THE 12Z NAM. GALE FORCE WIND GUSTS OVER THE OUTER NRN
WATERS THROUGH 06Z SUN. HELD ON TO THEM A LITTLE LONGER OVER THE
NRN INNER WATERS...EXTENDING THE GALE TO 08Z. WILL ALSO NEED TO
WATCH THE NRN PART OF PZZ255 AND PZZ275 AS GUSTS COULD TOUCH GALE
FORCE TONIGHT. MODELS IN DECENT AGREEMENT SHOWING SMALL CRAFT
ADVISORY SPEEDS LATE TONIGHT THROUGH EARLY SUN AFTERNOON. 12Z NAM
BOUNDARY LAYER WIND SPEEDS A LITTLE STRONGER 18Z SUN COMPARED TO
THE GFS. WIND SPEEDS EASE A BIT MON AS THE WARM FRONT LIFTS
N...REDUCING THE SURFACE GRADIENT. BASICALLY WENT WITH THE GFS FOR
WIND MON THROUGH TUE NIGHT. MODEL DIFFERENCES BECOME GREATER WED
THROUGH THU REGARDING THE NEXT SIGNIFICANT WEATHER SYSTEM. THE
ECMWF SEEMS TO BE MORE CONSISTENT...SHOWING POSSIBLE GALES LATE
WED THROUGH EARLY THU MORNING.
A LONG PERIOD NW SWELL WILL MAINTAIN SEAS 12 TO 15 FT THROUGH
TONIGHT AS THE WIND WAVE COMPONENT INCREASES. SEAS WILL SUBSIDE
TO AROUND 10 FT SUN AFTERNOON. LATEST ENP RUN HAS SEAS INCREASING
TO NEAR 15 FT LATE NEXT WEEK AND POSSIBLY NEAR 20 FT NEXT WEEKEND.
WANT TO SEE A FEW MORE RUNS BEFORE GOING THAT HIGH. CAPPED SEAS TO
AROUND 15 FT FOR NOW. WEISHAAR
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 PM PST THIS EVENING FOR
NORTHERN OREGON CASCADES.
WA...WINTER WEATHER ADVISORY UNTIL 4 AM PST SUNDAY FOR SOUTH
WASHINGTON CASCADES.
PZ...GALE WARNING UNTIL 10 PM PST THIS EVENING FOR WATERS FROM CAPE
SHOALWATER WA TO CASCADE HEAD OR FROM 10 TO 60 NM.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 6 PM PST SUNDAY FOR
COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST SUNDAY
FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60
NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10 AM
PST SUNDAY.
GALE WARNING UNTIL MIDNIGHT PST TONIGHT FOR COASTAL WATERS FROM
CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 10 NM.
&&
$$
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 PORTLAND OR
1009 AM PST SAT FEB 13 2016
.SYNOPSIS...A STRONG WARM FRONT WILL SPREAD INCREASING RAIN AND
BREEZY CONDITIONS INTO SOUTHWEST WASHINGTON AND NORTHWEST OREGON
THIS AFTERNOON AND TONIGHT...WITH RAIN HEAVY AT TIMES. SNOW LEVELS
WILL START NEAR THE CASCADE PASSES TODAY...BUT SHOULD RISE TONIGHT AS
WARMER AIR MOVES IN. THE FRONTAL ZONE WILL LINGER OVER THE AREA
SUNDAY...THEN LIFT NORTH SUNDAY NIGHT AND MONDAY FOR DECREASING RAIN.
HIGH PRESSURE WILL BRING DRIER WEATHER LATER MONDAY INTO TUESDAY...
ESPECIALLY FOR SOUTHERN ZONES. AN UPPER LEVEL TROUGH WILL BRING
COOLER AND SHOWERY WEATHER LATER WEDNESDAY INTO THURSDAY...WITH SNOW
POSSIBLE FOR THE CASCADE PASSES AND ABOVE.
&&
.MORNING UPDATE...NWS DOPPLER RADAR SHOWS WARM FRONTAL RAIN STARTING
TO MOVE ONSHORE TILLAMOOK NORTHWARD...THE START OF WHAT WILL BE A
VERY WET PERIOD WHICH SHOULD LAST INTO SUNDAY. LOOKING AT THE BIGGER
PICTURE...THIS FRONTAL SYSTEM HAS A DECENT MOISTURE TAP ALL THE WAY
BACK TO THE SUBTROPICAL LATITUDES NEAR THE DATELINE. BLENDED
PRECIPITABLE WATER VALUES SHOW 1.2 INCH OR HIGHER WITHIN THIS
MOISTURE PLUME AS FAR EAST AS 135W. 12Z NAM/GFS SUGGEST PW VALUES
AROUND 1 INCH REACHING OUR FORECAST AREA THIS EVENING...COUPLED WITH
OROGRAPHICALLY-FAVORABLE W-SW WINDS OF 40-50 KT AT 850 MB. THIS
SHOULD YIELD A PERIOD OF FAIRLY HEAVY RAINFALL FOR THE COAST AND
HIGHER TERRAIN...ESPECIALLY NORTHERN ZONES WHERE 2-4 INCHES OF RAIN
ARE POSSIBLE BY SUNDAY. INLAND VALLEYS WILL SEE LESS...RANGING FROM
ABOUT 0.50 INCH NEAR EUGENE TO 0.75-1.50 INCH IN THE PDX METRO. 12Z
GFS SHOWS THE BEST ISENTROPIC LIFT MOVING THROUGH BY MIDNIGHT
TONIGHT...AFTER THAT THE WILLAMETTE VALLEY IS LIKELY TO BE HEAVILY
RAIN SHADOWED IN LOW-LEVEL WESTERLY FLOW LATER TONIGHT INTO SUNDAY.
SNOW AMOUNTS WILL BE TRICKY FOR THE CASCADES WITH THIS SYSTEM. OFTEN
TIMES...LEFTOVER COLD AIR...WET-BULB EFFECTS AND LATENT HEAT
PROCESSES WILL HOLD ON TO LOWER SNOW LEVELS MOUNT HOOD NORTHWARD A
BIT LONGER THAN MODELS EXPECT. HOWEVER THIS DOES NOT APPEAR TO BE ONE
OF THOSE SCENARIOS AS FAIRLY STRONG WARM ADVECTION WILL BE MOVING IN
ON THE 40-50 KT W-SW 850-700 MB FLOW LATER TONIGHT. THERE WILL
PROBABLY BE SOME WET SNOW AT THE PASSES DURING THE ONSET OF
PRECIPITATION THIS AFTERNOON INTO THIS EVENING...BUT THIS SHOULD
CHANGE TO RAIN BY SUNDAY MORNING. HIGHER SKI RESORT ELEVATIONS LOOK
MORE LIKELY TO SEE 5-10 INCHES BEFORE SNOW LEVELS SKYROCKET TO 7000
FEET SUNDAY MORNING. IF SNOW LEVELS REMAIN LOWER THAN EXPECTED...
SNOW ACCUMULATIONS COULD BE SUBSTANTIALLY HIGHER GIVEN THE HEAVY QPF
THAT IS EXPECTED. HOWEVER...AM FAIRLY CONFIDENT THAT THE CHANGEOVER
WILL BE QUICK LATER TONIGHT OR SUNDAY MORNING. CURRENT WINTER WX
ADVISORY FOR SNOW APPEARS TO HANDLE ALL THIS WELL AND WILL NOT BE
MAKING ANY CHANGES FOR THE MORNING PACKAGE.
THE HEAVY RAINFALL MAY CAUSE SOME MINOR HYDROLOGIC ISSUES...MAINLY
FOR CREEKS AND SMALL STREAMS DRAINING OUT OF THE COAST RANGE AND
CASCADES. THE GRAYS RIVER IN WAHKIAKUM COUNTY IS NOTORIOUSLY FAST-
RESPONDING...SO 2-4 INCHES OF RAIN IN A 24 HOUR PERIOD MAY PUSH IT
CLOSE TO BANKFULL. WILL BE KEEPING A CLOSE EYE ON THIS RIVER AMONG
OTHERS AS RAIN INCREASES LATER TODAY AND TONIGHT. WEAGLE
/PREV DISC ISSUED 339 AM PST SAT FEB 13 2016/
.SHORT TERM...THE UPPER TROUGH ASSOCIATED WITH THE FRONTAL SYSTEM
FROM FRIDAY MOVED EASTWARD THROUGH SOUTHWEST WASHINGTON AND FAR
NORTHWEST OREGON OVERNIGHT...PRODUCING SHOWERS OVER MUCH OF THE
FORECAST AREA AND A FEW THUNDERSTORMS OVER THE NORTH COASTAL WATERS
AND THE IMMEDIATE COAST. THIS ACTIVITY WILL CONTINUE DECREASING THIS
MORNING.
ATTENTION THEN TURNS TO THE WARM FRONT APPROACHING 130W EARLY THIS
MORNING THAT WILL MOVE INTO THE FORECAST AREA THIS AFTERNOON AND
REMAIN OVER THE AREA THROUGH MUCH OF SUNDAY. THE FIRST WAVE ALONG
THIS WARM FRONT WILL SPREAD HEAVY RAIN INTO THE AREA THIS AFTERNOON
AND THROUGH AT LEAST THIS EVENING...WITH BRISK WINDS AT THE COAST
AND LOCALLY INLAND. THIS WAVE IS ACCOMPANIED BY 1.2 INCH
PRECIPITABLE WATER VALUES AND 850 MB WINDS OF NEARLY 50 KT. THIS
WAVE MOVES EAST OF THE AREA LATER SATURDAY NIGHT...BUT IS FOLLOWED
BY ONE OR TWO MORE SLIGHTLY WEAKER WAVES THAT KEEP THE RAIN GOING
THROUGH SUNDAY...THOUGH AT LESSER RAINFALL RATES.
SNOW LEVELS WILL START OUT IN THE CASCADES BETWEEN 3500 AND 4500 FEET
TODAY...AND WILL LINGER NEAR THE PASSES INTO TONIGHT. HAVE ISSUED A
SNOW ADVISORY OF THE SOUTH WASHINGTON CASCADES FROM NOON UNTIL AFTER
MIDNIGHT TONIGHT...ALSO THE NORTH OREGON CASCADES UNTIL 10 PM
TONIGHT. THE SNOW LEVEL DRAMATICALLY RISES FROM SOUTH TO NORTH
TONIGHT TO WELL ABOVE THE PASSES...TO WELL ABOVE 6000 FEET.
RAINFALL AMOUNTS OF 4 TENTHS OF TO OVER 1 INCH ARE POSSIBLE THIS
WEEKEND IN THE VALLEYS...WITH 2 TO 4 INCHES ALONG THE COAST AND IN
THE COAST RANGE AND THE CASCADES. THIS SURGE OF RAIN SHOULD CAUSE
MANY OF OUR FASTER RESPONDING RIVERS TO RISE RAPIDLY...PARTICULARLY
THE GRAYS RIVER IN WAHKIAKUM COUNTY...BUT MAIN STEM RIVER FLOODING
IS NOT ANTICIPATED. THE PERIOD WITH THE BEST CHANCE OF ANY URBAN
TYPE FLOODING WOULD BE LATER TODAY AND THIS EVENING.
THE WARM FRONT SHOULD MOVE MOSTLY NORTH OF OUR FORECAST AREA SUNDAY
NIGHT AND MONDAY WITH DECREASING RAIN. AS WE GET INTO THE WARM
SECTOR...WE COULD SEE TEMPS BACK INTO THE LOWER 60S AT LOWER
ELEVATIONS MONDAY. TOLLESON
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH FRIDAY...SHORTWAVE RIDGING EARLY IN THE WEEK
WILL ONCE AGAIN GIVE WAY TO A MORE ACTIVE WEATHER PATTERN DURING THE
MIDDLE TO LATTER HALF OF NEXT WEEK. THE REMNANTS OF AN ATMOSPHERIC
RIVER EVENT MAY DIP FAR ENOUGH SOUTH TO BRING SOME LIGHT RAIN TO THE
REGION TUESDAY...BUT CONFIDENCE IS LOW. MODELS HAVE BEEN IN MUCH
BETTER AGREEMENT THAT A SHORTWAVE TROUGH WILL SWING INTO THE WESTERN
UNITED STATES AND BRING WET AND COOLER WEATHER WEDNESDAY INTO
THURSDAY. AN ADDITIONAL STORM SYSTEM APPEARS POSSIBLE TOWARDS THE END
OF NEXT WEEK. TEMPERATURES FOR THE MOST PART SHOULD REMAIN NEAR TO
ABOVE NORMAL WITH ANY BOUTS OF PRECIPITATION LOOKING TO REMAIN LIGHT
ENOUGH THAT WE DO NOT FORESEE ANY MAJOR HYDROLOGIC ISSUES IN THE NEXT
WEEK. AB/NEUMAN
&&
.AVIATION...GENERALLY VFR AT 16Z...EXCEPT FOR AREAS OF MVFR ALONG
THE S WASHINGTON AND FAR N OREGON COAST. THE NEXT WARM FRONT WILL
IMPACT THE AREA LATE THIS AFTERNOON THROUGH SUNDAY. EXPECT
CONDITIONS TO DETERIORATE WITH INCREASING RAIN FROM NW TO SE MID
TO LATE AFTERNOON THROUGH TONIGHT...WITH IFR LIKELY ALONG THE
COAST. INTERIOR VALLEYS MAY ACTUALLY REMAIN VFR THIS AFTERNOON
THROUGH TONIGHT DUE TO SOME RAIN-SHADOW EFFECTS. STRONG 850 MB
WEST FLOW WILL RESULT IN ENHANCED OROGRAPHIC LIFT OVER THE HIGHER
TERRAIN...RESULTING IN MOUNTAIN OBSCUREMENT AND IFR OR WORSE
FLIGHT CONDITIONS.
KPDX AND APPROACHES...VFR PREVAILING TODAY...EXCEPT FOR POSSIBLE
MVFR CIGS MID TO LATE-AFTERNOON THROUGH EARLY EVENING AS PRECIP
INCREASES. S WIND SHOULD ALLOW FOR PRIMARILY VFR CONDITIONS LATER
THIS EVENING THROUGH SUN MORNING.
&&
.MARINE...WIND WILL INCREASE TODAY AS A WARM FRONT MOVES THROUGH
THE WATERS. 14Z RUC RUN A LITTLE STRONGER COMPARED TO THE LATEST
NAM. EXPECT SMALL CRAFT ADVISORY WIND SPEEDS TO RAMP UP TO GALE
FORCE WIND GUSTS LATE THIS EVENING OVER THE N OUTER WATERS. GALES
TO SPREAD INTO THE N INNER WATERS OVERNIGHT. GALES COULD LAST A
LITTLE LONGER THAN CURRENT FORECAST IMPLIES...BUT WILL LOOK AT
THAT MORE FOR THE AFTERNOON. RAMPED UP WIND SPEEDS A BIT SUN...WITH
SOLID SMALL CRAFT ADVISORY SPEEDS EXPECTED.
A LONG PERIOD NW SWELL WILL MAINTAIN 11 TO 13 FT SEAS TODAY THEN
12 TO 15 FT TONIGHT AS THE WIND WAVE COMPONENT INCREASES. SEAS
WILL SUBSIDE TO AROUND 10 FT SUN AFTERNOON. LATEST ENP RUN HAS
SEAS INCREASING TO NEAR 15 FT LATE NEXT WEEK.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 1 PM THIS AFTERNOON TO 10 PM
PST THIS EVENING FOR NORTHERN OREGON CASCADES.
WA...WINTER WEATHER ADVISORY FROM NOON TODAY TO 4 AM PST SUNDAY
FOR SOUTH WASHINGTON CASCADES.
PZ...GALE WARNING UNTIL 10 PM PST THIS EVENING FOR WATERS FROM
CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10 TO 60 NM.
SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM THIS AFTERNOON TO
6 PM PST SUNDAY FOR COASTAL WATERS FROM CASCADE HEAD OR TO
FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST SUNDAY
FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT
60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 6 AM
PST SUNDAY.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 10 PM PST THIS EVENING
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD
OR OUT 10 NM.
&&
$$
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
1230 PM EST SAT FEB 13 2016
.SYNOPSIS...
POLAR VORTEX OVR S QUEBEC WILL RAPIDLY LIFT NE BY LATE IN THE
WEEKEND. A DEEPENING UPPER LVL TROF OVER THE CENTRAL CONUS WILL
SPAWN A LOW PRES SYSTEM...WHICH WILL LIKELY TRACK NORTHWARD ACROSS
EASTERN PA ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED GRIDS FOR TEMPS/WINDS AND SNOW SHOWERS FOR QUICK LOOK AND
ACCIDENT ON I78 IN LEBANON COUNTY WHICH HAS EM PERSONNEL WORKING
ON SITE OF ACCIDENT.
PREVIOUS:
ARCTIC AIR MASS CONTINUES TO PUSH THROUGH THE REGION TODAY.
TEMPERATURES WILL NOT MOVE TOO MUCH HIGHER THAN CURRENT VALUES.
STRONG NORTHWEST WINDS AND TEMPERATURES IN JUST ABOVE ZERO IN THE
NORTHWESTERN AREAS TO A BALMY MID-TEENS IN THE SOUTHEAST WILL
PROVIDE FOR A VERY COLD DAY. WIND CHILLS BELOW ZERO OVER MOST OF
THE REGION TODAY INTO SUNDAY.
WIND GUSTS OF 25 TO 35 MPH HAVE BEEN OBSERVED SO FAR TODAY. COVER
UP WELL IF OUTDOORS OVER THE NEXT 36 HOURS OF SO.
RADAR AND SATELLITE IMAGERY SHOW HURON CONNECTION SNOW BANDS. ONE
BAND MADE INTO STATE COLLEGE AROUND 9 AM FOR A QUICK COATING. THIS
BAND IS MOVING TO THE SOUTHEAST AND COULD BRING LIGHT
SNOW/FLURRIES TO LOWER SUSQUEHANNA VALLEY LATER THIS MORNING.
MORE FOCUSED SNOW IS OVER SOUTHWEST MOUNTAINS. SNOW IN NORTHWESTER
AREAS HAS BEEN QUITE LIMITED. THE NCAR 3KM EFS AND THE HRRR SEEM
TO FOCUS SNOW IN SOUTHWEST MOUNTAINS AND HAVE LIMITED SNOW IN
THEIR RESPECTIVE FORECASTS. THE AIR IS VERY DRY AND HAS NOT BEEN A
PROLIFIC LAKE AND MOUNTAIN SNOW PRODUCER. HIGH RESOLUTION MODELS
KEEP INDICATING THIS. HRRR AT TIMES SHOWS A POTENTIAL MODEST BAND
IN NORTHWESTERN PA THIS EVENING.
COLD WILL BE THE ISSUE OVER THE ENTIRE REGION. BEST ACCUMULATING
SNOW POTENTIAL IN THE SOUTHWEST MOUNTAINS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
MODELS NOT VERY BIG IN SNOW OVERNIGHT INTO SUNDAY. SOME HINTS OF
SNOW EARLY IN THE HRRR AND SREF IN SW MOUNTAINS. COMBINED WITH THE
FALLING INVERSION HEIGHTS AHEAD OF APPROACHING HIGH...LES AND
MOUNTAIN SNOW THREATS WILL DIMINISH. THE HIGH SHOULD DECOUPLE SOME
AREAS OVERNIGHT AND WITH SNOW COVER A GOOD PERIOD OF RADIATIONAL
COOLING IS POSSIBLE IN CENTRAL AND WESTERN AREAS.
THE MASSIVE 1032 TO 1036 HIGH MOVES OVER THE REGION AND IS PARKED
OVERHEAD BY MIDDAY SUNDAY. THIS SHOULD ENSURE THE WINDS DIE AND
THE WINDCHILL ISSUE DIMINISH. BUT WILL STILL BE A VERY COLD
VALENTINES AT LEAST OUTDOORS.
THE EVENING SHOULD STILL HAVE NEAR IDEAL RADIATIONAL COOLING
CONDITIONS. VERY COLD START TO THE OVERNIGHT PERIOD SUNDAY INTO
MONDAY....BUT THE HIGH MOVES OFF FAST SUNDAY NIGHT. OVERNIGHT LOW
SUNDAY LIKELY WILL BE EARLY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
*IMPACT WEATHER HIGHLIGHTS: POTENTIAL WINTER STORM EARLY NEXT
WEEK.
BULK OF MED RANGE GUIDANCE INDICATES THE LIKELIHOOD OF SOME LGT
SNOW ARRIVING MONDAY...AS SFC HIGH DRIFTS OFF THE COAST AND MILDER
SOUTHERLY FLOW OVERRUNS RETREATING ARCTIC AIR MASS. HOWEVER...THE
BIGGER CONCERN INVOLVES DIGGING UPPER TROF OVR THE MISS VALLEY AND
ASSOC SFC LOW PRESSURE LIFTING UP THE APPALACHIANS. MDL SPREAD
CONTINUES TO NARROW...WITH MOST RUNS TRACKING SFC LOW ACROSS
EASTERN PA TUESDAY. THIS TRACK WOULD CERTAINLY FAVOR RAIN ACROSS
EASTERN PA AND RAIN OR SNOW ACROSS WESTERN PA. GIVEN INHERENT MDL
UNCERTAINTIES THIS FAR OUT...WILL MAINTAIN RAIN/SNOW IN THE FCST
FOR MOST OF CENTRAL PA MON NIGHT-TUES. HAVE RAISED POPS INTO THE
LIKELY CATEGORY BASED ON CONVERGING MDL SOLUTIONS.
WILL ALSO HAVE TO WATCH FOR THE POSSIBILITY OF FLOODING ACROSS
EASTERN PA...GIVEN RAINFALL AND SNOWMELT POTENTIAL. LATEST MDL
ENSEMBLE RIVER FORECASTS USING NAEFS SUGGESTS MINOR FLOODING IS A
POSSIBILITY ACROSS THE LOWER SUSQ VALLEY BY TUES. WPC ALSO HAS
HIGHLIGHTED SE PA FOR A SLIGHT RISK OF FLOODING TUESDAY.
NEAR TO ABOVE NORMAL TEMPS APPEAR LIKELY LATER NEXT WEEK...AS
HEIGHTS ARE FORECAST TO RISE AND A PSBL LOW PRESSURE SYSTEM LIFTS
THROUGH THE GREAT LAKES TO THE WEST OF PA.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
ARCTIC AIR HAS BROUGHT COLD TEMPERATURES AND STRONG GUSTY WINDS TO
THE REGION. SNOW SQUALLS ARE COMMON IN THE WESTERN MOUNTAINS WITH
IMPACTS ON KJST AND KBFD. SOME OF THE STRONGER LAKE STREAMERS AND
SNOW SHOWERS HAVE MADE TO THE MARYLAND BORDER IN SOUTHEASTERN PA.
SO SNOW AND BLOWING SNOW IS POSSIBLE WITH THE STRONG GUSTY WINDS.
GOOD GUST SPREADS TOO WHICH AFFECT TAKEOFF/LANDINGS. GUSTS OVER
30KTS HAVE BEEN OBSERVED.
IFR AND MVFR MOST OF WEST. VFR WITH TIME MVFR IN CENTRAL AREAS.
MOSTLY VFR WITH TIMES MVFR WITH SNOW/BLOWING SNOW IN SOME PARTS OF
SOUTHEAST TODAY.
THE SNOW SHOWERS AND WINDS WILL DIMINISH THIS EVENING AND
OVERNIGHT. THINGS SHOULD BE MUCH NICER SUNDAY...THOUGH A TAD COLD.
NEED A HEATED JOY STICK.
HIGH PRESSURE SUNDAY DRIFTS EAST OVERNIGHT SO THE PERIOD OF NICE
WEATHER WITH VFR WILL BE SHORT LIVED AS CLOUDS AND POTENTIAL
PRECIPITATION MOVE IN FOR MONDAY AND INTO TUESDAY. SNOW AND
ASSORTED WINTRY PRECIPITATION WILL LIKELY AFFECT FLYING MONDAY
INTO TUESDAY.
OUTLOOK...
SUN...NO SIG WX EXPECTED MAINLY VFR.
MON...WIDESPREAD RESTRICTIONS DEVELOP WITH SNOW DEVELOPING.
MON NIGHT AND TUE...SNOW LIKELY WRN HALF OF PENN...WITH RAIN
AND/OR SNOW IN THE SE. WIDESPREAD RESTRICTIONS SET IN. LLWS POSS
SE.
WED...ANOTHER WAVE SLIDES THROUGH KEEPING RESTRICTIONS IN
PLACE ALONG WITH POTENTIAL FOR LIGHT SNOW...ESP OVER THE WEST.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WIND CHILL WARNING UNTIL 11 AM EST SUNDAY FOR PAZ004>006-037-
041-042.
WIND CHILL ADVISORY UNTIL 11 AM EST SUNDAY FOR PAZ010>012-017-
018-024-033.
WIND ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR PAZ019-025>028-
034>036-045-046-049>053-056>059-063>066.
WIND CHILL ADVISORY FROM 5 PM THIS AFTERNOON TO 11 AM EST
SUNDAY FOR PAZ019-025>028-034>036-045-046-049>053-056>059-
063>066.
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ024-
033.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...GRUMM
SHORT TERM...GRUMM/FITZGERALD
LONG TERM...FITZGERALD/GARTNER
AVIATION...GRUMM
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
158 PM MST SAT FEB 13 2016
.UPDATE...
ISSUED AT 158 PM MST SAT FEB 13 2016
STRONG WINDS NOTED ALONG COLD FRONT MOVING INTO NORTHEAST
WY...GUSTING OVER 60 MPH FOR A BRIEF PERIOD IN SOME AREAS. BOTH
HRRR AND RUC SHOW THESE STRONG WINDS MOVING ACROSS NORTHEAST WY
DURING THE AFTERNOON AND INTO THE BLACK HILLS AREA LATE THIS
AFTERNOON/EARLY EVENING AS THE FRONT CROSSES. SHOWERS ACCOMPANYING
THE FRONT WILL ALSO HELP TO MIX STRONGER WINDS ALOFT DOWN. HAVE
DECIDED TO ISSUE A HIGH WIND WARNING FOR NORTHEAST WY AND MUCH OF
THE BLACK HILLS AREA. WINDS SHOULD DIMINISH WITH THE FRONT AS IT
MOVES EAST OF THE BLACK HILLS AND INTO COOLER AND MORE STABLE AIR
TO THE EAST.
UPDATE ISSUED AT 1238 AM MST SAT FEB 13 2016
CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER FAR SOUTHWEST SK...
WITH WARM FRONT EXTENDING SOUTHEAST INTO THE BLACK HILLS AREA AND
SOUTHWEST SD. COLD FRONT EXTENDS SOUTHWARD ACROSS CENTRAL MT INTO
NORTHWEST WY. UPPER LEVEL ANALYSIS SHOWS STRONG SHORTWAVE MOVING
EAST- SOUTHEAST ACROSS CENTRAL MT...WITH STRONG JET WRAPPING
AROUND IT FROM THE NORTHERN ROCKIES THROUGH SD. LATEST OBS SHOW
TEMPS RANGING FROM THE UPPER TEENS IN THE LEMMON AREA TO THE 50S
OVER CAMPBELL CO WY. THE FREEZING LINE RIGHT NOW EXTENDS FROM NEAR
BELLE FOURCHE TO NORTH OF PHILIP AND THEN SOUTH- SOUTHEAST TO
MELLETTE AND TODD COUNTIES IN SOUTH CENTRAL SD. KUDX RADAR SHOWING
SOME PCPN FROM MEADE CO INTO HAAKON AND ZIEBACH COUNTIES...MOSTLY
IN THE FORM OF RAIN...WITH SOME FREEZING RAIN OR SNOW LIKELY OVER
NORTHEAST MEADE INTO ZIEBACH CO. REGIONAL RADARS SHOW MORE
ACTIVITY DEVELOP TO THE WEST OVER SOUTH CENTRAL MT AND NORTH
CENTRAL WY NEAR THE SHORTWAVE AND COLD FRONT. SOME STRONG WINDS
HAVE ALSO BEEN NOTED NEAR THE FRONT AND WITH SHOWER ACTIVITY
THERE...AS TEMPS HAVE RISEN INTO THE 50S AND LOWER 60S. THESE
SHOWERS AND WIND WILL MOVE INTO NORTHEAST WY EARLY THIS AFTERNOON
AND REACH THE BLACK HILLS AREA LATE IN THE AFTERNOON. A SPECIAL
WEATHER STATEMENT HAS BEEN ISSUED FOR THE STRONG WIND GUSTS
EXPECTED WITH SHOWERS THIS AFTERNOON.
UPDATE HAS BEEN SENT TO ADJUST PCPN TYPE THIS AFTERNOON BASED ON
CURRENT TEMPS AND EXPECTED TRENDS. THE MAIN THREAT FOR FREEZING
RAIN AND A LITTLE SNOW WILL BE FROM PERKINS INTO ZIEBACH COUNTIES
THROUGH THE AFTERNOON. ICE ACCUMULATION UP TO A TENTH OF AN INCH
IS STILL EXPECTED. HARDING COUNTY WILL SEE TEMPS RISE TO ABOVE
FREEZING BY LATE AFTERNOON AS THE WARM FRONT MOVES THROUGH...
EVENTUALLY SWITCHING PCPN TO ALL RAIN. SOME ADJUSTMENTS WERE ALSO
MADE TO CLOUD COVER...WINDS...AND HIGH TEMPS.
&&
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT
ISSUED AT 327 AM MST SAT FEB 13 2016
UPPER TROUGH CONTINUES ACROSS THE ERN HALF OF THE CONUS WITH NW FLOW
OVER THE NRN PLAINS. A STRONG FAST MOVING SHORTWAVE IS CROSSING THE
CASCADES INTO THE NRN ROCKIES ATTM. CANADIAN HIGH PRES IS SITTING
ACROSS THE UPPER MIDWEST WITH A STRONG BAROCLINIC ZONE OVER THE
CNTRL TO ERN DAKOTAS. WARM AIR ADVECTION HAS BEGUN OVER THE CWA AS
THE FRONTAL BOUNDARY SLIDES E/NE. TEMPS AT 800MB HAVE RISEN ABOVE
FREEZING ACROSS MOST OF THE CWA...AND WILL DO SO INTO CNTRL SD OVER
THE NEXT 3 TO 6 HOURS. TEMPS WILL WARM ABOVE FREEZING TODAY ACROSS
NE WY TO MUCH OF WRN SD...HOWEVER FREEZING TEMPS ARE PROGGED ACROSS
PTNS OF NW/NCNTRL SD THROUGH MUCH OF TODAY. AS THE SHORTWAVE PUSHES
THROUGH THE REGION TODAY...PRECIP WILL DEVELOP ESPECIALLY ACROSS THE
NRN HALF OF THE AREA. WARM LOW LEVELS SHOW THIS WILL FALL AS RAIN.
CONCERN IS LINGERING SUB-FREEZING TEMPS ACROSS THE NRN PARTS OF
THE CWA WILL RESULT IN A PERIOD OF FREEZING RAIN ESPECIALLY
THROUGH THE AFTERNOON. WILL KEEP WINTER WEATHER ADVISORY ISSUED
YESTERDAY BUT HAVE EXPANDED IT ACROSS HARDING COUNTY WITH THE
SREF/HRRR SHOWING PRECIP POTENTIALLY BEGINNING LATE THIS MORNING
WHEN SURFACE TEMPS ARE STILL BELOW FREEZING. BEHIND THE SHORTWAVE
...SUB-FREEZING LOW LEVELS WILL QUICKLY PUSH BACK INTO THE REGION
ENDING THE THREAT FOR FREEZING RAIN AS IT BECOMES ALL SNOW IN THE
AFTERNOON/EVENING. PARTS OF NW/CNTRL SD COULD SEE 1 TO 3 INCHES
OF ACCUMULATION BEFORE PRECIP ENDS DURING THE OVERNIGHT HOURS.
WITH LOW LEVEL INSTABILITY THAT DEVELOPS...MAY EVEN A FEW
LIGHTNING STRIKES. MODELS SHOWING 700-850MB WINDS REACHING 50KT
BRIEFLY NEAR THE FRONTAL BOUNDARY WHICH WOULD CREATE A SHORT
PERIOD OF STRONG WINDS FOR NOT MORE THAN AN HOUR OR SO.
W/NW WINDS WILL CONTINUE ACROSS THE AREA SUNDAY AS LOW PRESSURE SITS
EAST OF THE AREA. WARMER TEMPS NEAR THE SURFACE WILL ALLOW HIGHS TO
REACH THE UPPER 30S TO UPPER 40S...HOWEVER COOLER 700MB TEMPS WILL
RESULT IN INSTABILITY IN THE LOW LEVELS WHICH WILL ALLOW FOR
UPSLOPING TO DEVELOP ACROSS THE NRN/WRN BLKHLS. PRECIP WILL BE RAIN
EXCEPT SOME SNOW AT THE HIGHEST ELEVATIONS. THIS LIGHT PRECIP WILL
LINGER INTO SUNDAY NIGHT.
.LONG TERM...MONDAY THROUGH FRIDAY
ISSUED AT 327 AM MST SAT FEB 13 2016
EASTERN NOAM TROUGH WILL BREAKDOWN IN THE PERIOD...ALLOWING MEAN
RIDGING TO SPREAD EAST INTO CENTRAL NOAM. THIS WILL RESULT IN A
TREND TO VERY MILD/DRY CONDS BY MID WEEK AS STAUNCH WAA SPREADS
INTO THE NORTHERN PLAINS. BEFORE THIS OCCURS...ANOTHER NW FLOW
IMPULSE WILL ADVECT ACROSS THE NORTHERN PLAINS...SUPPORTING RA/SN
SHOWERS MON INTO TUE. VERY WARM WEATHER CAN BE EXPECTED BY WED AND
ESP THUR. HIGHS ACROSS THE FA THUR LOOK TO APPROACH AND PASS 70 AT
SOME LOCATIONS...ESP IN THE LEE OF THE BH WHERE DOWNSLOPING WILL
BE IN PLACE AHEAD OF A DEEP SFC CYCLONE THAT WILL ADVECT EAST
THROUGH THE REGION SPURRED BY AMPLIFIED ACTIVE FLOW OVER THE
EASTERN PAC. THUR-FRI LOW PRESSURE SYSTEM MAY ALSO SUPPORT ANOTHER
HIGH WIND EVENT IN THE REGION TOWARD THE END OF THE WORK WEEK
GIVEN PROGGED CAA/PRESSURE RISE COUPLET. ACTIVE JET ACROSS THE PAC
LOOKS TO SUPPORT MILD ZONAL FLOW THROUGH THE MIDDLE/END OF NEXT
WEEK...KEEPING ARCTIC AIR BOTTLED UP IN NORTHERN CANADA AS RIDGING
REMAINS CONFINED TO LOWER LATITUDES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY)
ISSUED AT 1021 AM MST SAT FEB 13 2016
MVFR/IFR CIGS OVER NORTHWEST INTO CENTRAL SOUTH DAKOTA WILL
CONTINUE THROUGH THIS AFTERNOON AND EVENING AS AREA OF SN/FZRA
DEVELOPS. THE HEAVIEST PRECIPITATION WILL BE THIS AFTERNOON INTO
TONIGHT. FOR NORTHEAST WYOMING INTO SOUTHWEST SOUTH
DAKOTA...SHOWERS WILL DEVELOP THIS AFTERNOON/EVENING WITH LCL MVFR
CIGS/VSBY. COLD FRONT CROSSES THE AREA LATE AFTERNOON/EVENING
WITH A PERIOD OF GUSTY NORTHWEST WINDS. VFR CONDITIONS EXPECTED
ACROSS THE AREA SUNDAY MORNING.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 8 PM MST THIS EVENING FOR SDZ001-
002-014.
HIGH WIND WARNING UNTIL 8 PM MST THIS EVENING FOR SDZ012-024>031-
072>074.
WY...HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON FOR WYZ054>058-
071.
&&
$$
UPDATE...26
SHORT TERM...13
LONG TERM...JC
AVIATION...7
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
237 PM CST SAT FEB 13 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 235 PM CST SAT FEB 13 2016
FAIRLY ACTIVE SHORT TERM FORECAST FOR THE AREA AS TWO FEATURES
WILL COMBINE TO PRODUCE MODERATE TO OCCASIONALLY HEAVY SNOWFALL
OVER THE CWA. THE STRONG SHORTWAVE THAT WILL SLIDE SOUTHEAST
ACROSS SOUTHWEST SOUTH DAKOTA IS STILL LOCATED IN CENTRAL MONTANA
AT THIS TIME...AND IS LEADING TO A COUPLE AREAS OF PRECIPITATION
IN EASTERN MONTANA (ONE ALONG THE WARM FRONT AND ANOTHER TIED TO
THE SHORTWAVE AND COLD FRONT). CLOSER TO THE AREA...SEEING
PRECIPITATION JUST TO THE WEST OF THE MISSOURI RIVER THAT IS
SLOWLY MOVING EAST-SOUTHEAST. THIS PRECIPITATION IS DUE TO THE
INITIAL AREA OF MID-LEVEL WARM AIR ADVECTION AHEAD OF THE WARM
FRONT STRETCHING SOUTH-SOUTHEAST THROUGH FAR WESTERN SOUTH DAKOTA.
WEBCAMS SHOW THAT THE PRECIPITATION TOWARDS HAAKON/STANLEY
COUNTIES IS IN THE FORM OF RAIN AND WITH SURFACE TEMPERATURES IN
THAT AREA AROUND OR ABOVE FREEZING...DON/T THINK THERE IS TOO MUCH
FREEZING RAIN OCCURRING AT THIS POINT. FARTHER NORTH...RAP
ANALYSIS SOUNDINGS INDICATE THE WARM NOSE ALOFT WEAKENS WHICH
SHOULD TRANSITION THE PRECIP TO SNOW THE FARTHER NORTH YOU HEAD.
OVER THE REST OF THE AREA...CLOUDS HAVE BEEN LOWERING WITH THE
INCREASING LOW LEVEL MOISTURE AND DEPARTING SURFACE RIDGE.
TEMPERATURES ARE STILL FAIRLY COLD OVER NORTHEAST SD...WHERE 2PM
TEMPERATURES RANGE FROM THE UPPER SINGLE DIGITS AT K8D3 TO 13 AT
KABR AND THEN 17 AT KMBG.
MODELS CONTINUING TO STRUGGLE WITH THE TRACK/EVOLUTION OF THE
SHORTWAVE IN MONTANA...WHICH LEADS TO SOME UNCERTAINTY IN THE
FORECAST SNOWFALL OVER N.C./N.E. SOUTH DAKOTA THIS EVENING INTO
THE OVERNIGHT HOURS. LATEST RUNS OF THE RAP AND 12Z GLOBAL
MODELS HAVE TRENDED THE TRACK OF THE STRONGEST FORCING A LITTLE
FARTHER TO THE SOUTHWEST AND IN SOME CASES ONLY BARELY BRUSHING
SOUTHWESTERN SD. WHILE THAT BEST FORCING SLIDES SOUTHWEST OF
MUCH OF THE AREA...STILL HAVE SOME SUPPORT FROM THE UPPER TROUGH
AND ESPECIALLY FROM THE WARM AIR ADVECTION / ISENTROPIC ASCENT
ALONG AND AHEAD OF THAT TROUGH THROUGH THE EARLY OVERNIGHT
HOURS. FAIRLY STRONG LIFT WITH THE WAA (AND SEEN IN THE 700MB
OMEGA) WITH FAVORABLE 850-500MB Q-VECTOR DIVERGENCE.
THEREFORE...EXPECT TO SEE A FAIRLY QUICK HITTING (4-7HR PERIOD)
AREA OF PRECIPITATION MOVING THROUGH THE AREA...ESPECIALLY THIS
EVENING INTO THE EARLY OVERNIGHT HOURS. MODELS HAVE TRENDED QPF
AMOUNTS TO THE NORTH WITH THE MOST RECENT RUNS...SOME EVEN
SHOWING 12HR QPF AMOUNTS EXCEEDING 0.6IN BETWEEN
MOBRIDGE/ABERDEEN. THAT POTENTIAL (LIKELY SOMEWHAT CONVECTIVELY
DRIVEN WITH 750-500MB LAPSE RATES AROUND 7 C/KM) WILL NEED TO BE
WATCHED THROUGH THE EVENING AND IF IT SETS UP AS SHOWN WITH SOME
OF THE HIGHER RES RUNS...MAY NEED TO UPGRADE A FEW COUNTIES TO
WARNINGS. WITH THAT FARTHER NORTH TREND...EXPECT A LITTLE LESS
IMPACT FOR THE SOUTHWESTERN CWA...BUT STILL THINK THE POTENTIAL
FOR FREEZING RAIN THROUGH THE FIRST PART OF THE EVENING BEFORE
TRANSITIONING TO SNOW FOR A BRIEF PERIOD BEFORE ENDING. THAT
NORTHWARD SHIFT SHOULD KEEP SNOWFALL AMOUNTS BELOW 2 INCHES FROM
PIERRE AND SOUTHWEST (WHERE SOME AREAS WILL STAY MAINLY RAIN).
AS FOR SNOWFALL AMOUNTS OVER THE NORTH CENTRAL AND
NORTHEAST...HAVE A GENERAL 3-6 INCHES WITH SNOW RATIOS
INCREASING FROM AROUND 10-1 AROUND THE MISSOURI RIVER TO THE
12-14 TO 1 RANGE OVER THE NORTHEAST. OVER THE NORTHEAST...A GOOD
PORTION OF THE LIFT IS AT OR ABOVE THE DGZ...WHICH WILL LIKELY
LEAD TO MORE COLUMNS IN THE SNOW PROCESS AND MORE POTENTIAL FOR
COMPACTING (ALONG WITH AGGREGATION AS THE SNOW FALLS THROUGH THE
CLOUD LAYER BELOW THE DGZ). THUS...DIDN/T WANT TO GO MUCH HIGHER
THAN THE PREVIOUSLY MENTIONED VALUES ...ALTHOUGH RATIOS COULD
BRIEFLY INCREASE IF THE FORCING ALIGNS A LITTLE LOWER AND IN THE
DGZ. WITH THE HIGHER QPF AND RATIOS...HAVE NEAR WARNING SNOWFALL
AMOUNTS (5.5-6IN) OVER MCPHERSON/EDMUNDS/BROWN/MARSHALL/DAY
COUNTIES. WITH THE VARIABILITY IN THE MODEL RUNS TODAY...DIDN/T
HAVE ENOUGH CONFIDENCE TO UPGRADE TO A WARNING AT THIS POINT AND
THE EVENING SHIFT WILL NEED TO MONITOR FOR A POSSIBLE UPGRADE. IN
ADDITION...WITH THE SNOW OCCURRING LATE THIS EVENING AND DURING
THE EARLY OVERNIGHT HOURS...THOUGHT THE IMPACTS WOULD BE LOWER
THAN IF IT OCCURRED DURING THE DAY.
ONE OTHER ITEM TO MENTION WILL BE THE GUSTY SOUTH-SOUTHEAST
WINDS INITIALLY THIS EVENING AHEAD OF THE TROUGH (GUSTS TO
25-30MPH). THAT WILL LEAD TO PATCHY/AREAS OF BLOWING SNOW AND
WILL CONTINUE TO MENTION THAT IN THE FORECAST/WSW.
FOR THE REST OF THE PERIOD...THE SNOW WILL DIMINISH FROM WEST TO
EAST LATE TONIGHT AND THROUGH THE DAY ON SUNDAY (LARGELY OVER
THE EASTERN HALF/THIRD OF THE CWA). A BROAD SURFACE TROUGH WILL
BE OVER THE AREA AND LIMIT THE WINDS AND IN TURN ANY BLOWING SNOW
CONCERNS. IN ADDITION...WITH THE WARM AIR OVER THE
AREA BEHIND THE WARM FRONT THAT MOVED THROUGH...HIGHS WILL RISE
INTO THE MID/UPPER 20S OVER THE FAR EAST TO THE LOWER 40S ALONG
AND WEST OF THE MISSOURI RIVER.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 235 PM CST SAT FEB 13 2016
LOW TEMP FORECAST FOR SUNDAY NIGHT IS A BIT TRICKY. AREA WILL STILL
BE IN A RELATIVELY MILD AIR MASS WITH 925MB TEMPS AROUND 0C TO +2C
AND A LIGHT WEST TO SOUTHWEST SFC WIND. ALTHOUGH...WILL HAVE TO KEEP
IN MIND THE FRESH COAT OF SNOW THAT WILL BE OVER MUCH OF THE AREA.
THERE WILL BE SOME DEGREE OF CLOUD COVER AS WELL...SO TRYING TO
FIGURE OUT WHICH VARIABLES HAVE THE BIGGEST IMPACT ON TEMPS IS
TRICKY.
WILL THEN BE WATCHING THE NEXT PIECE OF SHORTWAVE ENERGY WHICH WILL
BE DROPPING SOUTHEAST THROUGH THE AREA MONDAY NIGHT. HAVE INCREASED
POPS FOR THIS EVENT AS MODELS ARE IN PRETTY GOOD AGREEMENT ON TIMING
AND PLACEMENT OF QPF. AGAIN...COULD BE DEALING WITH MIXED PRECIP
ISSUES AS THERE WILL BE WARM AIR IN PLACE.
YET ANOTHER WAVE MOVES THROUGH TUESDAY NIGHT BUT IS LOOKING RATHER
WEAK AT THIS POINT. SUPERBLEND GAVE SLIGHT CHANCE POPS AND THIS
LOOKS GOOD FOR THE TIME BEING. ONLY CHANGE HERE WAS TO REMOVE THE
SLIGHT CHANCES THEY INITIAL GAVE ON TUESDAY AND HELD THINGS OFF TO
TUESDAY NIGHT PER MODEL DATA.
TEMPS THROUGHOUT THE PERIOD STAY ON THE MILD SIDE...ESPECIALLY BY
THURSDAY WHEN MODELS TRY TO BRING IN SOME VERY MILD AIR. 925MB TEMPS
AROUND +20C SHOW UP IN THE MODELS OVER SOUTHWEST AND SOUTH CENTRAL
SD. SUPERBLEND TEMPS HAVE READINGS AS WARM AS THE 60S OVER THE
SOUTHWEST CWA ON THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1149 AM CST SAT FEB 13 2016
EXPECT DETERIORATING CONDITIONS FROM WEST TO EAST THROUGH THE
AFTERNOON AND EVENING ACROSS THE REGION...AS A STORM SYSTEM
SLIDES EAST-SOUTHEAST ACROSS THE AREA. HAVE ALREADY STARTED TO
SEE SOME REDUCTIONS IN VISIBILITY AT KMBG AND EXPECT
VISIBILITIES TO FALL TO LOW END IFR AT ALL THE SITES AS THE
HEAVIEST SNOW MOVES THROUGH. COULD BRIEFLY SEE LIFR VISIBILITIES
FIRST OVER THE WEST LATE THIS AFTERNOON THROUGH LATE EVENING AND
THEN AT KABR/KATY BETWEEN 02-08Z (COMBINATION OF THE HEAVY SNOW
AND BLOWING SNOW BEFORE WINDS DIMINISH). EXPECT VISIBILITIES TO
RAPIDLY IMPROVE OVER THE WEST AFTER MIDNIGHT AS THE SYSTEM SHIFTS
TO THE EAST (VFR CONDITIONS WEST BY MID MORNING)...ALTHOUGH MVFR
CONDITIONS WILL PREVAIL THROUGH SUNDAY MORNING OVER THE EAST.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 6 AM CST /5 AM MST/ SUNDAY FOR SDZ003-
004-009-015-016-033>036-045-048-051.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON CST SUNDAY
FOR SDZ005>008-010-011-017>023-037.
MN...WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON CST SUNDAY
FOR MNZ039-046.
&&
$$
SHORT TERM...SRF
LONG TERM...TDK
AVIATION...SRF
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1220 PM CST SAT FEB 13 2016
.AVIATION...
MVFR CIGS NOTED ACROSS THE SWRN TWO THIRDS OF THE CWFA THIS MORN/
AFTN...GENERALLY ALONG AND SOUTH OF THE WEAK FRONTAL BOUNDARY. AS
THE LINE WEAKENS/MOVES BACK FURTHER INLAND THIS EVENING/OVERNIGHT
WE COULD SEE WIDESPREAD LOWER/MVFR CIGS ACROSS SE TX BY SAT MORN.
SOME SPOTS MIGHT SEE PATCHY FOG OVERNIGHT AS WELL...BUT FOG COULD
BE MORE PREVALENT SUN MORN. 41
&&
.PREV DISCUSSION... /ISSUED 925 AM CST SAT FEB 13 2016/
UPDATE...
FIRST VISIBILITY HAS IMPROVED SOUTH OF A FRONTAL BOUNDARY SO LET
DENSE FOG ADVISORY EXPIRE.
BASED ON 15Z SFC OBS...FRONTAL BOUNDARY LOCATED FROM LA GRANGE TO
SUGAR LAND TO GALVESTON. LATEST 14Z HRRR HAS THIS BOUNDARY FAIRLY
WELL RESOLVED AND BEGINS TO PUSH THE BOUNDARY BACK NORTH LATER
THIS AFTERNOON AND TURNS WINDS TO SE. THERE MAY BE ENOUGH CLOUD
COVER AND COOLER AIR TO KEEP MAX TEMPS IN THE 60S BUT MAY STILL
FEEL HUMID WITH DEWPOINTS IN THE 50S SOUTH OF THE BOUNDARY. MAIN
UPDATES TO THE FORECAST WERE TO ENSURE CONSISTENCY WITH ONGOING
TRENDS AND LATEST SHORT RANGE GUIDANCE. OVERALL NOT A LOT OF
CHANGE FROM THE PREVIOUS UPDATE.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 67 52 71 56 71 / 10 10 20 20 20
HOUSTON (IAH) 68 51 71 58 72 / 10 10 20 30 30
GALVESTON (GLS) 61 56 69 58 68 / 10 10 20 20 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...99
AVIATION/MARINE...41