Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/05/16
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
830 PM MST MON JAN 4 2016
.SYNOPSIS...
SEVERAL STORM SYSTEMS WILL MOVE THROUGH THE AREA THIS WEEK...BRINGING
COOLER AFTERNOON HIGHS...MILD NIGHTS...CLOUDY SKIES...AND AN ELEVATED
CHANCE OF RAINFALL THROUGH THE END OF THE WEEK. CONDITIONS WILL
START TO DRY OUT FOR THE COMING WEEKEND...BUT TEMPERATURES WILL
REMAIN BELOW SEASONAL NORMALS.
&&
.DISCUSSION...
MAIN MID-TROPOSPHERIC TROUGH AXIS CONTINUES TO PIVOT CYCLONICALLY
INTO NORTHERN AND EASTERN AZ. FROM A QUASI-GEOSTROPHIC
PERSPECTIVE...FORCING FOR ASCENT HAS BEEN WANING. HOWEVER...WEAK
ISENTROPIC MOISTURE TRANSPORT HAS BEEN SUFFICIENT TO SUPPORT A SOLID
LINE OF LIGHT TO MODERATE RAIN ACROSS SOUTH-CENTRAL AZ. LATEST RUNS
OF THE HRRR INDICATE THE LINE WILL CONTINUE TO DISSIPATE AS IT SLIDES
EASTWARD THIS EVENING. SOME LOCATIONS HAVE PICKED UP AS MUCH AS A
HALF OF AN INCH OF RAIN IN THIS LINE AND ANOTHER TENTH OF AN INCH IS
POSSIBLE...MAINLY ACROSS PORTIONS OF THE EAST VALLEY. GENERAL
CONSENSUS AMONGST THE HI-RES GUIDANCE IS THAT THE ACTIVITY WILL THEN
BECOME MORE ISOLATED THROUGH MIDNIGHT...BEFORE SHIFTING INTO THE
FAVORED AREAS OF THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX. MINOR
ADJUSTMENTS WERE MADE TO THE SHORT-TERM TEMPERATURES...DEWPOINTS AND
WINDS. OTHERWISE...THE FORECAST REMAINS ON TRACK.
&&
.PREVIOUS DISCUSSION...
LOOKING AT A MIXED CONFIDENCE FORECAST OVER THE NEXT FEW DAYS AS A
SERIES OF TROUGHS WILL MOVE THROUGH AND IMPACT THE AREA. THERE IS
VERY HIGH CONFIDENCE THAT ALL LOCATIONS WILL SEE MEASURABLE
PRECIPITATION AT SOME POINT /IF NOT SEVERAL TIMES OVER/ BY THE END OF
THE WEEK. THE UNCERTAINTY RESIDES IN EXACTLY WHEN THE RAIN WILL
OCCUR. RAINFALL LOOKS TO TAPER OFF THIS EVENING AND OVERNIGHT AS THE
INITIAL TROUGH AND RESULTING SUBSIDENCE BEGINS TO DOMINATE OVER THE
REGION. BY SOME INDICATIONS...TUESDAY MORNING SHOULD START OFF
RELATIVELY DRY. HOWEVER...MOIST ADVECTION /MODEST IVT SIGNAL FROM GFS
AND GEFS/ AND WEAK ISENTROPIC FORCING WILL BEGIN DURING THE DAY IN
ADVANCE OF A SECOND TROUGH...WITH RAINFALL POSSIBLE AGAIN TUESDAY
AFTERNOON AND EVENING. SREF PRECIP PLUMES ARE ADMITTEDLY ALL OVER THE
MAP UNTIL 06Z WEDNESDAY...AT WHICH POINT NEARLY ALL 26 MEMBERS
SUGGEST MEASURABLE PRECIP ACROSS THE DESERTS. DECIDING EXACTLY WHEN
THE RAIN WILL START IS A CHALLENGE...BUT POPS HAVE BEEN ADJUSTED TO
HIGHLIGHT THE LATE TUESDAY/EARLY WEDNESDAY TIME PERIOD AS ANOTHER
OPPORTUNITY FOR RAINFALL. THIS SECONDARY TROUGH SHOULD RAPIDLY MOVE
THROUGH THE AREA WEDNESDAY MORNING AND THE OPERATIONAL RUNS OF THE
ECMWF...NAM...AND GFS ARE EVEN TRYING TO SUGGEST SOME BREAKS IN THE
CLOUDS WEDNESDAY AFTERNOON.
TROUGH NUMBER 3 APPEARS POISED TO ARRIVE LATE WEDNESDAY NIGHT/EARLY
THURSDAY MORNING WITH ANOTHER NARROW BAND OF ENHANCED IVT AND
ISENTROPIC FORCING. ONCE AGAIN IT APPEARS THAT ELEVATED POPS ARE
WARRANTED AT THIS POINT AND THEY WERE NUDGED TOWARD THE LATEST RUN OF
THE NAEFS. FOLLOWING A BRIEF BREAK...THE FOURTH AND POSSIBLY FINAL
TROUGH LOOKS TO BE QUEUED UP FRIDAY MORNING WITH DRYING AND WEAK
UPPER RIDGING BEGINNING TO TAKE HOLD EARLY SATURDAY MORNING. QUITE A
BUSY WEEK TO SAY THE LEAST.
IN TERMS OF PRECIP AMOUNTS FOR THE WEEK AS A WHOLE...A HEALTHY BLEND
OF 50TH PERCENTILE QPF FROM ALL AVAILABLE GUIDANCE WEIGHTED TOWARD
WPC VALUES YIELDS ABOUT 1.5 TO 1.75 INCHES OVER THE DESERTS...WITH
SOME TOTALS PUSHING 3 INCHES NORTH/EAST OF PHOENIX. IT WOULD APPEAR
AT NO TIME SHOULD WE BE LOOKING AT MORE THAN A QUARTER TO A HALF INCH
OVER A 6 HR PERIOD. WASHES WILL LIKELY BEGIN RUNNING IN SOME AREAS
THIS WEEK AND SOME LOW-LYING AREAS COULD SEE MINOR HYDRO ISSUES...BUT
WIDESPREAD FLOODING DOESN`T APPEAR LIKELY AT THIS POINT. SHOULD THE
FORECAST VERIFY AS ADVERTISED...THIS SHOULD BE A STRATIFORM/BENEFICIAL
RAIN FOR THE AREA VS. A MAJOR HYDRO OR FLOODING EVENT. COLDER AIR
WILL EVENTUALLY WORK ITS WAY INTO THE AREA LATE IN THE WEEK RESULTING
IN SOME MIXED PRECIPITATION ACROSS THE HIGHEST MOUNTAIN PEAKS
NORTH/EAST OF PHOENIX. AT THIS POINT IT APPEARS ANY NOTEWORTHY
ACCUMULATIONS WILL BE CONFINED TO THE VERY HIGHEST PEAKS AND LOWEST
IMPACT AREAS ABOVE 6000 FT.
NORTHWEST FLOW AND WEAK DRY ADVECTION ACROSS THE AREA LOOKS LIKELY
THROUGH THE WEEKEND INTO NEXT WEEK...ALTHOUGH THERE`S SOME HINT AT A
DRY TROUGH MOVING THROUGH THE AREA ON SUNDAY /SOME INCREASED CLOUD
COVER AND THAT`S ABOUT IT/. SHOULD THIS TROUGH NOT DEVELOP...WE`LL NEED
TO KEEP AN EYE ON FOG POTENTIAL THIS WEEKEND /SATURDAY OR SUNDAY/ IF
THE BL DOESN`T SUFFICIENTLY DRY OUT. THE PATTERN IS CERTAINLY
CONDUCIVE FOR WIDESPREAD FOG DEVELOPMENT ACROSS THE AREA AND IT
WARRANTS MENTIONING. FAIRLY GOOD AGREEMENT OF STRONG UPPER RIDGING
ACROSS THE AREA BY MONDAY OF NEXT WEEK WITH TEMPERATURES RETURNING TO
EARLY JANUARY NORMALS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
EXPECT SHOWERS WITH CIGS AT AREA TERMINALS AS LOW AS 5000 FEET
THIS AFTERNOON WITH A COUPLE HOURS OF IMPROVEMENT POSSIBLE THROUGH
03Z. CIGS WILL CONTINUE TO LOWER THIS EVENING/OVERNIGHT THRU TUESDAY
MORNING TO AS LOW AS 3000 FEET...ESPECIALLY AT KSDL. WINDS WILL
FAVOR THE EAST NEXT 24 HOURS THROUGH 15Z TUESDAY...MOSTLY LESS THAN
12KT. IT IS POSSIBLE THAT VISIBILITIES MAY LOWER NEAR OR BELOW 5SM
LATER OVERNIGHT IN AN ISOLATED HEAVIER SHOWER.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
EXPECT CIGS PERSIST 3000-5000 FEET AND ISOLATED SHOWERS TO PERSIST
INTO THE EVENING...WITH SOME IMPROVEMENT AFTER 06Z TUESDAY TO AROUND
6000 FEET ACROSS THE AREA. DO NOT EXPECT VISIBILITY RESTRICTIONS...
BUT ITS POSSIBLE TO DIP TO 5SM FOR SHORT PERIODS OF TIME...HOWEVER
CONFIDENCE IS LOW TO PUT IN THE TAFS AT THIS TIME.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
SEVERAL WEATHER DISTURBANCES WILL MOVE THROUGH THE DISTRICTS IN CLOSE
SUCCESSION THIS WEEK WITH HIGHLY VARIABLE RAINFALL OCCURRING EACH
DAY THROUGH FRIDAY...MAINLY EAST OF THE LOWER COLORADO RIVER VALLEY.
RAIN CHANCES TAPER OFF FOR THE WEEKEND. HUMIDITY WILL BE MUCH ABOVE
AVERAGE WITH MINIMUM VALUES NEAR AND ABOVE 45 PERCENT MOST DAYS ON
THE LOWER DESERTS AND MAX VALUES NEAR AND ABOVE 80 PERCENT MUCH OF
THE TIME. VALUES TREND DOWN FROM WEST TO EAST SATURDAY INTO SUNDAY
BUT GENERALLY REMAIN ABOVE 30 PERCENT MOST PLACES. EXPECT WELL BELOW
NORMAL HIGH TEMPERATURES THROUGH FRIDAY WITH DESERT HIGHS IN THE
50S...AND SLIGHT WARMING OVER THE WEEKEND AS HUMIDITIES START TO
FALL OFF. DESPITE THE ACTIVE WEATHER PATTERN NO STRONG WIND EVENTS
ARE EXPECTED BUT JUST BREEZY AT TIMES...MAINLY WEDNESDAY AND
THURSDAY.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
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DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...LEINS
AVIATION...MEYERS
FIRE WEATHER...AJ/CB
AREA FORECAST DISCUSSION
NWS TUCSON AZ
300 PM MST SUN JAN 3 2016
.SYNOPSIS...A SERIES OF WET STORM SYSTEMS WILL BRING VALLEY
RAIN...MOUNTAIN SNOW AND COOLER TEMPERATURES THIS WEEK.
&&
.DISCUSSION...GUSTY EASTERLY SURFACE WINDS...OTHERWISE ANOTHER MILD
DAY FOR SOUTHEAST ARIZONA. SOME MOISTURE INCREASE ALREADY OCCURRING
IN THE STRENGTHENING SOUTHWESTERLY FLOW (BEHIND THE RIDGE AMPLIFYING
IMMEDIATELY DOWNSTREAM AND AHEAD OF THE FIRST IN A SERIES OF WET
PACIFIC STORMS THIS WEEK). 12Z KTWC SOUNDING WAS UP TO 1/2 INCH
PRECIPITABLE WATER WITH 3/4 INCH VALUES ALREADY BREACHING THE
SIERRAS OF SOUTHERN CALIFORNIA AND NORTHERN BAJA CIRA LAYERED PW
IMAGERY. LATEST HRRR TRENDS SHOW INCREASING SURFACE DEW POINTS FROM
THE NORTHERN GULF OF CALIFORNIA INTO LOWER WESTERN DESERTS OVER THE
NEXT 15 HOURS.
CONFIDENCE REMAINS VERY HIGH FOR A SERIES WET-TRAJECTORY STORMS FROM
THE PACIFIC WITH POTENTIALLY SIGNIFICANT VALLEY RAIN AND MOUNTAIN
SNOW AMOUNTS THIS COMING WEEK. JUDGING BY OPERATIONAL MODEL BLENDS
AS WELL AS ENSEMBLE MEANS...THE INITIAL IMPULSE WILL HAVE THE
GREATEST IMPACT ON OUR PART OF THE STATE FROM MONDAY AFTERNOON INTO
TUESDAY MORNING. FOLLOWING THAT...THE BEST PERIODS FOR OUR PART OF
THE STATE APPEAR TO BE WEDNESDAY...THURSDAY NIGHT AND FRIDAY
AFTERNOON INTO SATURDAY MORNING.
AS MENTIONED ABOVE OUR AVAILABLE MOISTURE SHOULD BE PLENTIFUL WITH
RELATIVELY EFFICIENT PRECIPITATION PROCESSES. FOR THE ENTIRE MONDAY
THROUGH FRIDAY PERIOD WE CONTINUE TO INCREASE OUR QPF VALUES WITH
CONSERVATIVE ESTIMATES OF 1/2 TO 1.25 INCHES IN VALLEYS AND 1 TO 2.5
INCHES IN MOUNTAINS. SNOW LEVELS ABOVE 7000 FEET FOR MOST OF THE
WEEK WITH SNOW AMOUNTS IN EXCESS OF 1 FT POSSIBLE AT HIGHER MOUNTAIN
LOCATIONS (AND WELL ABOVE THAT ON HIGHEST MOUNTAIN PEAKS).
THE LAST IMPULSE ON FRIDAY INTO SATURDAY MAY HAVE A HYBRID MOIST AND
COOLER TRAJECTORY FROM THE NORTHWEST. THAT WOULD MAKE FOR COOLER
TEMPERATURES AND LOWER SNOW LEVELS FRIDAY AND SATURDAY. THE ECMWF
HAS ANOTHER IMPULSE JUST NORTH OF THE AREA SUNDAY.
&&
.AVIATION...VALID THRU 04/23Z.
SKC CONDITIONS-SCT CLOUDS AROUND 15K FT AGL THRU 04/05Z. THEN EXPECT
INCREASING CLOUDS AND LOWERING CLOUD DECKS THROUGH THE REST OF THE
FORECAST PERIOD. SCT-BKN CLOUDS AT 8-12K FT AGL AND BKN-OVC CLOUDS
AT 12-16K FT AGL BY 04/12Z...AND THEN BKN-OVC CLOUDS AT 4-7K FT AGL
BY 04/23Z. SCATTERED VALLEY -SHRA AND MOUNTAIN -SHSN DEVELOPING AFT
04/15Z...BECOMING NUMEROUS BY 04/21Z WITH LOCAL MVFR CONDITIONS AND
MOUNTAIN OBSCURATIONS. ELY/SELY SURFACE WIND AT 7-15 KTS...WITH
GUSTS TO BETWEEN 15-20 KTS THRU 04/03Z. ELY/SELY SURFACE WIND WILL
THEN DECREASE TO 12 KTS OR LESS AFT 04/03Z. SELY/SLY SURFACE WIND AT
10-15 KTS AFT 04/20Z. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.
&&
.FIRE WEATHER...DRY CONDITIONS WITH LOCALLY GUSTY EAST WINDS WILL
CONTINUE THROUGH THE EVENING HOURS TONIGHT. THERE WILL THEN BE A BIG
CHANGE IN THE WEATHER PATTERN THIS WEEK...WITH PERIODS OF VALLEY
RAIN AND MOUNTAIN SNOW...AND MUCH COOLER TEMPERATURES MONDAY THROUGH
FRIDAY. LINGERING SHOWERS WILL OCCUR MAINLY EAST OF TUCSON SATURDAY
FOLLOWED BY DRY CONDITIONS AREA-WIDE NEXT SUNDAY.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
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MEYER/ZELL
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
251 PM PST SUN JAN 3 2016
...HEAVY RAIN AND STRONG SOUTHEASTERLY WINDS POSSIBLE LATE MONDAY
NIGHT AND TUESDAY...
.SYNOPSIS...RAIN WILL SPREAD OVER MOST OF THE REGION BY LATE
TODAY. THIS WILL BE THE FIRST IN A SERIES OF WEATHER SYSTEMS
EXPECTED TO IMPACT CALIFORNIA THROUGH THE UPCOMING WEEK. THE
SECOND STORM ON MONDAY NIGHT AND TUESDAY WILL BE STRONGER AND
COULD PRODUCE HEAVY RAIN AND LOCALLY STRONG WINDS. AT LEAST TWO
MORE STORMS WILL FOLLOW ON WEDNESDAY AND THURSDAY.
&&
.DISCUSSION...AS OF 2:47 PM PST SUNDAY...ONE WORD TO DESCRIBE THE
UPCOMING WEEK...WET. STORMS THUS FAR THIS WINTER HAVE BEEN FAIRLY
TYPICAL...COLD AND MORE FROM THE NORTHWEST. FOR THE UPCOMING WEEK
THE BAY AREA MAY FINALLY START SEEING A MORE EL NINO TYPE STORM
TRACK FROM THE WEST- SOUTHWEST WITH A GOOD SUB-TROPICAL JET.
THAT BEING SAID...A SERIES OF STORMS ARE STILL ON TRACK TO IMPACT
THE BAY AREA TODAY THROUGH NEXT WEEKEND. LATEST SATELLITE IMAGERY
OVER THE PACIFIC ACTUALLY SHOWS A PARADE OF STORMS MARCHING TOWARD
THE COAST. THE FIRST LOW PRESSURE IS ALREADY BRINGING RAIN TO THE
BAY AREA. KMUX RADAR IMAGERY HAS BEEN SHOWING ECHOES SINCE THIS
MORNING WITH MAINLY LIGHT TO LOCALLY MODERATE RAIN. HIGHEST
RAINFALL HAS BEEN MAINLY CONFINED TO THE NORTH BAY WHERE SIX HOUR
RAINFALL TOTALS ARE JUST UNDER 0.5 INCHES. FARTHER SOUTH RAIN HAS
BEEN HARD TO COME BY...SAN FRANCISCO AND OAKLAND ONLY TRACED AND
SAN JOSE HAS NOT REPORTED ANY RAIN. THE DRIER CONDITIONS ARE
LIKELY DUE TO THE UPPER TROUGH BECOME MORE NEGATIVELY TILTED AND
DRIER SOUTHEASTERLY FLOW. HOWEVER...LATEST MODEL GUIDANCE
CONTINUES TO MARCH THE COLD FRONT CURRENTLY OFF THE COAST INLAND
WITH RAIN EVENTUALLY DEVELOPING AFTER 02Z THIS EVENING. RAIN WILL
CONTINUE TONIGHT THROUGH EARLY MONDAY. RAINFALL TOTALS THROUGH
MONDAY EVENING WILL BE 1 TO 1.5 INCHES NORTH BAY AND COASTAL
MOUNTAINS...ELSEWHERE 0.5 TO 1 INCHES...EXCEPT INLAND VALLEYS
0.25-0.75 INCHES.
THE SECOND STORM SYSTEM HAS SPED UP A LITTLE ON THE LATEST
GUIDANCE AND IS NOW MORE TIMED FOR LATE MONDAY NIGHT THROUGH
TUESDAY. IF THE LATEST GUIDANCE IS CORRECT...MODERATE TO LOCALLY
HEAVY RAIN WILL IMPACT THE MORNING COMMUTE TUESDAY. THE SECOND
SYSTEM STILL APPEARS TO BE THE WETTEST OF THE BUNCH. RAINFALL
TOTALS 1.5 TO 2.5 INCHES NORTH BAY AND COASTAL MOUNTAINS...
ELSEWHERE GENERALLY 0.5 TO 1.5 INCHES. THIS FRONTAL BOUNDARY ALSO
HAS A LITTLE MORE CONVECTIVE ELEMENT TO IT WITH DECENT SFC
CAPE...NEG LI/S AND GOOD LAPSE RATES. THEREFORE...HAVE ADDED A
SLIGHT CHC FOR THUNDER MAINLY SAN JOSE NORTHWARD TUESDAY
AFTERNOON. SHORTWAVE RIDGING DEVELOPS TUESDAY EVENING WITH A
BRIEF BREAK/OR SCATTERED SHOWERS. COLDER AIR MOVES IN DURING THIS
TIME PERIOD AS WELL WITH SNOW LEVELS DROPPING TO 4000-4500 FEET.
A THIRD SYSTEM WILL QUICKLY FOLLOW FOR MORE PRECIP WEDNESDAY
THROUGH THURSDAY NIGHT. LIGHT TO MODERATE RAINFALL WILL ACCOMPANY
THIS FRONTAL PASSAGE. GIVEN THE LOWER SNOW LEVELS...RAIN/SNOW WILL
BE POSSIBLE OVER THE HIGHER PEAKS OF MONTEREY/SAN BENITO COUNTIES.
NO ACCUMULATION IS EXPECTED. THE HIGHEST RAINFALL LOOKS TO MORE
FOCUSED OVER THE SANTA CRUZ MTS AND THE BIG SUR COAST WITH ANOTHER
1 TO 2 INCHES POSSIBLE.
SOME DRYING IS EXPECTED ON FRIDAY AND FRIDAY NIGHT...BUT LONG
RANGE MODELS BRING YET ANOTHER SYSTEM WITH MORE PRECIP NEXT
WEEKEND. DETAILS AND TIMING ARE A LITTLE UNCERTAIN GIVEN THAT IT
IS PRETTY FAR OUT. NEEDLESS TO SAY...RAINFALL AMOUNTS OVER THE
NEXT 6 DAYS WILL BE PRETTY DECENT WITH A FEW SPOTS ECLIPSING 6-7
INCHES. LOOKING EVEN FURTHER INTO THE FUTURE...THE LATEST CPC 6-10
DAY AND 8-14 DAY OUTLOOKS SHOW HIGHER THAN NORMAL CHANCES FOR
RAINFALL. STAY TUNED.
&&
.AVIATION...AS OF 9:45 AM PST SUNDAY...RAIN HAS MOVED INTO THE
NORTH BAY WITH THE MAIN BAND STILL AROUND 20 NM TO THE WEST OF THE
COAST. LATEST RUN OF THE HRRR SHOWS THAT EASTWARD PROGRESSION WILL
BE SLOW WITH ONSET AT MOST TERMINALS AFTER 0Z. VFR WILL GIVE WAY
TO MVFR AT MOST SPOTS BY LATE IN THE AFTERNOON OR THE EVENING.
WINDS FROM 100 TO 130 OF 10 TO 20 KT EXPECTED NEAR 0Z. MODERATE
CONFIDENCE.
VICINITY OF KSFO...VFR THROUGH AT LEAST 22Z AND POSSIBLY UNTIL 02Z
TOMORROW DEPENDING ON THE ARRIVAL TIME OF THE RAIN. MVFR EXPECTED
AFTER THAT WITH BOTH VIS AND CIG. WINDS WILL BE MOSTLY 100 TO 130
WITH SPEEDS UNDER 12 KT. POSSIBLE WE COULD SEE SOME LLWS DUE TO
SPEEDS. MODERATE CONFIDENCE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR UNTIL AROUND 0Z THEN MVFR AFTER
THAT DUE TO RAIN. MVFR CIGS AND VIS FORECAST FROM AROUND 0Z UNTIL
16Z OR SO. 110 TO 130 WINDS TO 25 KT AT KSNS. MODERATE
CONFIDENCE.
&&
.MARINE...AS OF 9:40 AM PST SUNDAY...UNSETTLED WEATHER WITH
MODERATE WINDS CAN BE EXPECTED ALL WEEK AS A SERIES OF STORM
SYSTEMS WILL PASS OVER THE COASTAL WATERS. IN ADDITION A SERIES OF
LARGE WESTERLY SWELL TRAINS WILL ALSO IMPACT THE WATERS THIS
WEEK...THE FIRST IS EXPECTED TO ARRIVE TUESDAY WITH A SECOND
LARGER SET ANTICIPATED FOR THURSDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PT REYES TO PIGEON PT 0-10 NM
SCA...PIGEON PT TO PT PINOS 0-10 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT ARENA TO PIGEON PT 10-60 NM
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: MM
AVIATION: BELL
MARINE: BELL
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
959 AM PST SUN JAN 3 2016
...HEAVY RAIN AND STRONG SOUTHEASTERLY WINDS POSSIBLE LATE MONDAY
NIGHT AND TUESDAY...
.SYNOPSIS...RAIN WILL SPREAD OVER MOST OF THE REGION BY LATE
TODAY. THIS WILL BE THE FIRST IN A SERIES OF WEATHER SYSTEMS
EXPECTED TO IMPACT CALIFORNIA THROUGH THE UPCOMING WEEK. THE
SECOND STORM ON MONDAY NIGHT AND TUESDAY WILL BE STRONGER AND
COULD PRODUCE HEAVY RAIN AND LOCALLY STRONG WINDS. AT LEAST TWO
MORE STORMS WILL FOLLOW ON WEDNESDAY AND THURSDAY.
&&
.DISCUSSION...AS OF 08:37 AM PST SUNDAY...A COLD FRONT KNOCKING
ON THE DOOR STEP WILL BRING RAINFALL TO THE BAY AREA THIS
AFTERNOON AND OVERNIGHT. IN THE MEANTIME...SCATTERED SHOWERS WILL
BE POSSIBLE THIS MORNING...ESPECIALLY THE NORTH BAY. THE LEADING
EDGE OF PRECIP WILL BE MAINLY LIGHT. A FEW BUCKETS HAVE ALREADY
TIPPED IN THE NORTH BAY OVER THE LAST THREE HOURS. VENADO AND PT
REYES BOTH SHOW 0.04 INCHES. LATEST SFC ANALYSIS SHOWS THE COLD
FRONT ABOUT 100-150 MILES WEST OF THE COAST. INTERESTING TO
NOTE...THERE HAS ALSO BEEN SOME NOCTURNAL CONVECTION ALONG THE
BOUNDARY WITH LIGHTNING ABOUT 200-250 WEST OF PT CONCEPTION.
FOR THE REST OF TODAY...THE LATEST HRRR CONTINUES TO BRING THE
FRONT EASTWARD WITH INCREASING PRECIP COVERAGE. THE HEAVIER RAIN
SHOWERS CAN ALREADY BE SEEN ON THE KMUX RADAR IMAGERY. AS NOTED ON
PREVIOUS DISCUSSIONS...DYNAMICS ARE SOMEWHAT WEAK AND THE
ORIENTATION OF THE UPPER TROUGH BECOMES NEGATIVELY TILTED.
THEREFORE...THE INLAND AREAS WILL SEE LESS RAINFALL...ESPECIALLY
THE CENTRAL VALLEY. HIGHEST RAINFALL TOTALS THROUGH MONDAY WILL BE OVER
THE NORTH BAY AND COASTAL MOUNTAINS. NO UPDATE IS PLANNED THIS
MORNING.
STRONGER AND WETTER STORMS ARE EXPECTED MIDWEEK. SEE BELOW FOR
DETAILS.
&&
.PREV DISCUSSION...AS OF 3:08 AM PST SUNDAY...
THE SECOND SYSTEM IS FORECAST TO MOVE ACROSS THE DISTRICT MONDAY
NIGHT AND TUESDAY. THIS SECOND SYSTEM IS EXPECTED TO BE STRONGER
AND COULD BRING PERIODS OF HEAVY RAIN TO SOME AREAS LATE MONDAY
NIGHT INTO TUESDAY MORNING. WINDS ARE ALSO EXPECTED TO BE STRONGER.
THE STRONGEST WINDS AND HEAVIEST RAINFALL ARE EXPECTED TO BE OVER
THE COASTAL HILLS...MAINLY SOUTH OF THE GOLDEN GATE.
THE NEXT SYSTEM IS SLATED TO MOVE THROUGH ON WEDNESDAY WITH
ANOTHER ROUND OF RAIN AND GUSTY WINDS...WITH YET ANOTHER SYSTEM
EXPECTED ON THURSDAY. PROJECTED RAINFALL TOTALS THROUGH THURSDAY
GIVE 2 TO 5 INCHES TO THE FORECAST AREA...WITH HEAVIEST AMOUNTS
EXPECTED IN THE SANTA CRUZ AND SANTA LUCIA MOUNTAIN RANGES.
A FEW SHOWERS COULD PERSIST THROUGH FRIDAY...BUT MEDIUM RANGE
MODELS INDICATE A RIDGE WILL BRIEFLY BUILD OVER THE WEST DURING
NEXT WEEKEND FOR DRIER CONDITIONS. A RETURN TO A MORE ACTIVE
PATTERN IS POSSIBLE AFTER THE WEEKEND.
&&
.AVIATION...AS OF 9:45 AM PST SUNDAY...RAIN HAS MOVED INTO THE
NORTH BAY WITH THE MAIN BAND STILL AROUND 20 NM TO THE WEST OF THE
COAST. LATEST RUN OF THE HRRR SHOWS THAT EASTWARD PROGRESSION WILL
BE SLOW WITH ONSET AT MOST TERMINALS AFTER 0Z. VFR WILL GIVE WAY
TO MVFR AT MOST SPOTS BY LATE IN THE AFTERNOON OR THE EVENING.
WINDS FROM 100 TO 130 OF 10 TO 20 KT EXPECTED NEAR 0Z. MODERATE
CONFIDENCE.
VICINITY OF KSFO...VFR THROUGH AT LEAST 22Z AND POSSIBLY UNTIL 02Z
TOMORROW DEPENDING ON THE ARRIVAL TIME OF THE RAIN. MVFR EXPECTED
AFTER THAT WITH BOTH VIS AND CIG. WINDS WILL BE MOSTLY 100 TO 130
WITH SPEEDS UNDER 12 KT. POSSIBLE WE COULD SEE SOME LLWS DUE TO
SPEEDS. MODERATE CONFIDENCE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR UNTIL AROUND 0Z THEN MVFR AFTER
THAT DUE TO RAIN. MVFR CIGS AND VIS FORECAST FROM AROUND 0Z UNTIL
16Z OR SO. 110 TO 130 WINDS TO 25 KT AT KSNS. MODERATE
CONFIDENCE.
&&
.MARINE...AS OF 9:40 AM PST SUNDAY...UNSETTLED WEATHER WITH
MODERATE WINDS CAN BE EXPECTED ALL WEEK AS A SERIES OF STORM
SYSTEMS WILL PASS OVER THE COASTAL WATERS. IN ADDITION A SERIES OF
LARGE WESTERLY SWELL TRAINS WILL ALSO IMPACT THE WATERS THIS
WEEK...THE FIRST IS EXPECTED TO ARRIVE TUESDAY WITH A SECOND
LARGER SET ANTICIPATED FOR THURSDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PIGEON PT TO PT PINOS 0-10 NM
SCA...PT ARENA TO PIGEON PT 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 1 PM
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: MM
AVIATION: BELL
MARINE: BELL
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
837 AM PST SUN JAN 3 2016
...HEAVY RAIN AND STRONG SOUTHEASTERLY WINDS POSSIBLE LATE MONDAY
NIGHT AND TUESDAY...
.SYNOPSIS...RAIN WILL SPREAD OVER MOST OF THE REGION BY LATE
TODAY. THIS WILL BE THE FIRST IN A SERIES OF WEATHER SYSTEMS
EXPECTED TO IMPACT CALIFORNIA THROUGH THE UPCOMING WEEK. THE
SECOND STORM ON MONDAY NIGHT AND TUESDAY WILL BE STRONGER AND
COULD PRODUCE HEAVY RAIN AND LOCALLY STRONG WINDS. AT LEAST TWO
MORE STORMS WILL FOLLOW ON WEDNESDAY AND THURSDAY.
&&
.DISCUSSION...AS OF 08:37 AM PST SUNDAY...A COLD FRONT KNOCKING
ON THE DOOR STEP WILL BRING RAINFALL TO THE BAY AREA THIS
AFTERNOON AND OVERNIGHT. IN THE MEANTIME...SCATTERED SHOWERS WILL
BE POSSIBLE THIS MORNING...ESPECIALLY THE NORTH BAY. THE LEADING
EDGE OF PRECIP WILL BE MAINLY LIGHT. A FEW BUCKETS HAVE ALREADY
TIPPED IN THE NORTH BAY OVER THE LAST THREE HOURS. VENADO AND PT
REYES BOTH SHOW 0.04 INCHES. LATEST SFC ANALYSIS SHOWS THE COLD
FRONT ABOUT 100-150 MILES WEST OF THE COAST. INTERESTING TO
NOTE...THERE HAS ALSO BEEN SOME NOCTURNAL CONVECTION ALONG THE
BOUNDARY WITH LIGHTNING ABOUT 200-250 WEST OF PT CONCEPTION.
FOR THE REST OF TODAY...THE LATEST HRRR CONTINUES TO BRING THE
FRONT EASTWARD WITH INCREASING PRECIP COVERAGE. THE HEAVIER RAIN
SHOWERS CAN ALREADY BE SEEN ON THE KMUX RADAR IMAGERY. AS NOTED ON
PREVIOUS DISCUSSIONS...DYNAMICS ARE SOMEWHAT WEAK AND THE
ORIENTATION OF THE UPPER TROUGH BECOMES NEGATIVELY TILTED.
THEREFORE...THE INLAND AREAS WILL SEE LESS RAINFALL...ESPECIALLY
THE CENTRAL VALLEY. HIGHEST RAINFALL TOTALS THROUGH MONDAY WILL BE OVER
THE NORTH BAY AND COASTAL MOUNTAINS. NO UPDATE IS PLANNED THIS
MORNING.
STRONGER AND WETTER STORMS ARE EXPECTED MIDWEEK. SEE BELOW FOR
DETAILS.
&&
.PREV DISCUSSION...AS OF 3:08 AM PST SUNDAY...
THE SECOND SYSTEM IS FORECAST TO MOVE ACROSS THE DISTRICT MONDAY
NIGHT AND TUESDAY. THIS SECOND SYSTEM IS EXPECTED TO BE STRONGER
AND COULD BRING PERIODS OF HEAVY RAIN TO SOME AREAS LATE MONDAY
NIGHT INTO TUESDAY MORNING. WINDS ARE ALSO EXPECTED TO BE STRONGER.
THE STRONGEST WINDS AND HEAVIEST RAINFALL ARE EXPECTED TO BE OVER
THE COASTAL HILLS...MAINLY SOUTH OF THE GOLDEN GATE.
THE NEXT SYSTEM IS SLATED TO MOVE THROUGH ON WEDNESDAY WITH
ANOTHER ROUND OF RAIN AND GUSTY WINDS...WITH YET ANOTHER SYSTEM
EXPECTED ON THURSDAY. PROJECTED RAINFALL TOTALS THROUGH THURSDAY
GIVE 2 TO 5 INCHES TO THE FORECAST AREA...WITH HEAVIEST AMOUNTS
EXPECTED IN THE SANTA CRUZ AND SANTA LUCIA MOUNTAIN RANGES.
A FEW SHOWERS COULD PERSIST THROUGH FRIDAY...BUT MEDIUM RANGE
MODELS INDICATE A RIDGE WILL BRIEFLY BUILD OVER THE WEST DURING
NEXT WEEKEND FOR DRIER CONDITIONS. A RETURN TO A MORE ACTIVE
PATTERN IS POSSIBLE AFTER THE WEEKEND.
&&
.AVIATION...AS OF 4:05 AM PST SUNDAY...THE CURRENT IR SATELLITE
IMAGE IS SHOWING HIGH CLOUDS PUSHING OVER THE FORECAST AREA THIS
MORNING AHEAD OF AN APPROACHING STORM SYSTEM. AT THIS POINT DRY
AIR IS PREVENTING RAIN FROM REACHING THE GROUND. HOWEVER AS THE
STORM SYSTEM CONTINUES TO PUSH TOWARDS THE COAST THE ATMOSPHERE
WILL MOISTEN ENOUGH FOR RAIN TO REACH THE GROUND. FORECAST MODELS
ARE SUGGESTING THAT THIS WILL OCCUR BY LATE MORNING EARLY
AFTERNOON.
VICINITY OF KSFO...VFR CONDITIONS ARE EXPECTED TO PERSIST INTO
THE EVENING HOURS WITH BASES DEVELOPING AT SCT035 BY 2000Z WITH
LIGHT RAIN. A PERIOD OF MODERATE SHOWERS WILL BE POSSIBLE BETWEEN
2200Z AND 0200Z. WET RUNWAYS CAN BE EXPECTED INTO MONDAY MORNING.
EASTERLY WINDS ARE EXPECTED TO REACH 12 KT WITH GUSTS TO 15 KT.
CONFIDENCE IS MODERATE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR CONDITIONS ARE EXPECTED TO
PERSIST INTO THE EVENING HOURS WITH BASES DEVELOPING AT SCT035 BY
2000Z WITH LIGHT RAIN. A PERIOD OF MODERATE SHOWERS WILL BE
POSSIBLE BETWEEN 0402Z AND 0405Z. WET RUNWAYS CAN BE EXPECTED
INTO MONDAY MORNING. EASTERLY WINDS ARE EXPECTED TO BE GENERALLY
LIGHT IN MONTEREY...HOWEVER SOUTHEASTERLY WINDS ARE ANTICIPATED TO
REACH 20 TO 25 KT WITH GUSTS TO 30 KT IN THE SALINAS VALLEY.
CONFIDENCE IS MODERATE.
&&
.MARINE...AS OF 02:01 AM PST SUNDAY...A SERIES OF STORM SYSTEMS
WILL PASS OVER THE COASTAL WATERS THIS WEEK BRINGING RAIN AND
PERIODS OF MODERATE TO STRONG WINDS. IN ADDITION A SERIES OF LARGE
WESTERLY SWELL TRAINS WILL ALSO IMPACT THE WATERS THIS WEEK...THE
FIRST IS EXPECTED TO ARRIVE TUESDAY WITH A SECOND LARGER SET
ANTICIPATED FOR THURSDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PIGEON PT TO PT PINOS 0-10 NM
SCA...PT ARENA TO PIGEON PT 10-60 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 1 PM
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: MM
AVIATION: LARRY
MARINE: LARRY
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
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AREA FORECAST DISCUSSION...CORRECTED
NWS NEW YORK NY
1002 PM EST MON JAN 4 2016
.SYNOPSIS...
CANADIAN HIGH PRESSURE BUILDS OVER THE AREA THROUGH
TUESDAY...THEN BUILDS TO THE SOUTH TUESDAY NIGHT THROUGH THURSDAY.
ANOTHER AREA OF HIGH PRESSURE BUILDS TO THE NORTH THURSDAY NIGHT
AND FRIDAY...RETREATING TO THE CANADIAN MARITIMES FRIDAY NIGHT AND
SATURDAY. AN UNSETTLED WEATHER PATTERN LOOKS IN STORE FOR THE
AREA OVER THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
MADE MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN
OBSERVATIONS AND GUIDANCE. THE FORECAST APPEARS GENERALLY ON
TRACK.
700-300 HPA TROUGH AXIS SWINGS THROUGH INTO THE EARLY MORNING
HOURS...THEN DEEP LAYERED RIDGING BEGINS TO BUILD IN TOWARDS
MORNING. FLURRIES HAVE BASICALLY EXITED TO THE S/E...AND ANY
LINGERING STRATO-CUMULUS SHOULD DISSIPATE AS THE TROUGH AXIS
SLIDES TO THE EAST/RIDGING BEGINS TO BUILD IN. STILL ON TRACK FOR
CLEAR SKY CONDITIONS OVERNIGHT.
COLD AIR ADVECTION AND A TIGHT PRESSURE GRADIENT WILL RESULT IN A
CONTINUATION OF GUSTY WINDS AND PLUMMETING TEMPS. AFTER RECORD
WARMTH FOR NOVEMBER AND DECEMBER...THE COLDEST NIGHT OF THE SEASON
IS ANTICIPATED. WITH COLD BEING LIMITED BY STRENGTH OF WIND TO
WHAT COLD ADVECTION BRINGS IN. NOTING ALREADY TEMPERATURES UNDER
CUTTING FORECAST BY 2-4 DEGREES AT MANY LOCATIONS. HAVE UPDATED
USING A BLEND OF THE LOWEST VALUE OF LAV/MAV/MET GUIDANCE AND NAM
AND HRRR 2-METER TEMPERATURES AND THOSE INDIVIDUAL CONSTITUENTS.
THE BLEND WAS WEIGHED TOWARDS THE COLDEST VALUE AT ANY GIVEN
POINT. LOWS GENERALLY 10-15 NEAR THE COAST...EXCEPT UPPER TEENS
EASTERN TWIN FORKS OF LONG ISLAND...AND SINGLE DIGITS ELSEWHERE.
ALSO...WINDS RUNNING A TAD STRONGER THAN PREVIOUSLY FORECAST...SO
IMPACT OF GUSTY NORTH WINDS WITH A SLIGHTLY COLDER TEMPERATURE
FORECASTS...WILL PRODUCE WIND CHILLS SLIGHTLY COLDER THAN
PREVIOUSLY FORECAST AT MOST LOCATIONS. WIND CHILL VALUES
OVERNIGHT WILL RUN AROUND ZERO TO 5 BELOW ACROSS NYC/LONG ISLAND
AND 5 TO 10 BELOW ELSEWHERE.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/...
RIDGE BUILDS THIS TIME FRAME BEHIND THE DEPARTING TROUGH.
SUBSIDENCE WILL ENSURE CLEAR SKIES THROUGH WED.
AS THE CENTER OF HIGH PRESSURE NEARS...ANY RESIDUAL GUSTS
WILL DIMINISH TUESDAY...AND WINDS REMAIN LIGHT OR CALM TUESDAY NIGHT.
A VERY COLD START TO THE DAY IS EXPECTED...AND TEMPS REMAIN QUITE
CHILLY TUESDAY...REMAINING BELOW FREEZING FOR THE MOST PART ACROSS
THE CWA.
AT NIGHT...TEMP FORECAST IS A BIT MORE CHALLENGING. WARM AIR
ADVECTION WILL BE UNDERWAY...BUT CLEAR SKIES AND LIGHT WINDS WILL
PROMOTE RADIATIONAL COOLING. THERE IS A TEMP DISPARITY IN THE MOS
GUIDANCE...AND AMONG ENSEMBLE GUIDANCE. WILL NOT STRAY TOO FAR
FROM PREVIOUS FORECAST...TAKING A BLEND OF AVAILABLE GUIDANCE BUT
SIDING ON THE LOWER END OF THE SPREAD.
TEMPS MODIFY ON WEDNESDAY AS THE CENTER OF THE HIGH PASSES TO THE
SOUTH AND RETURN FLOW W/SW WINDS PREVAIL.
TEMPS LIKELY RISE CLOSE TO IF NOT JUST ABOVE SEASONAL NORMS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
THE H5 FLOW IS IN GOOD AGREEMENT THROUGH FRI...BUT THEN DIFFERENCES
BEGIN TO TAKE SHAPE FROM THE INTERACTION BETWEEN A LARGE CANADIAN
VORTEX OVER HUDSON BAY AND A CUTOFF LOW PRES SYSTEM MOVING ONSHORE
OUT WEST. THE 12Z MODELS SEEM TO BE IN SOMEWHAT BETTER AGREEMENT
THAN THE 00Z RUNS WITH THE OVERALL PATTERN...THAT BEING THE
ELONGATED E-W ORIENTED VORTEX BECOMING N-S ORIENTED WITH A COLDER
AIRMASS DIVING INTO THE NORTHERN PLAINS/UPPER MIDWEST/GREAT LAKES
FOR THE WEEKEND. THIS VORTEX WILL THEN MEANDER ABOUT ERN ONTARIO
THROUGH THE MIDDLE OF NEXT WEEK.
IN TERMS OF SENSIBLE WEATHER...DRY AND NEAR TO SLIGHTLY ABOVE NORMAL
TEMPERATURES THROUGH FRI WITH HIGH PRES IN CONTROL. WARM AIR
ADVECTION RAINS MOVE INTO THE AREA FRI NIGHT THROUGH
SAT...ALTHOUGH THE RETREATING HIGH TO THE NORTH WILL RESULT IN
COLD AIR DAMMING WITH A POSSIBILITY OF A WINTRY MIX OF
PRECIPITATION ACROSS THE INTERIOR TO START. SHOULD TURN TO PLAIN
RAIN AT ALL LOCATIONS BY SAT AFTERNOON. THE AMOUNT OF QPF REMAINS
IN QUESTIONS AS THERE IS THE POTENTIAL FOR A WAVE OF LOW PRES TO
DEVELOP OFF THE MID ATLANTIC COAST AND PASS SOUTH OF LONG ISLAND
ON SAT. HAVE KEPT LOW CHANCE POPS IN THE FORECAST SAT NIGHT INTO
SUN...ALTHOUGH WE MAY END UP SEEING A LULL IN PRECIPITATION BEFORE
THE NEXT POTENTIAL SYSTEM TRACKS UP FROM THE S. THIS SYSTEM
CURRENTLY LOOKS WARM ENOUGH FOR ALL RAIN...BUT IF THE UPPER
PATTERN CHANGES AND THE STORM SHIFTS A BIT FURTHER OFFSHORE...IT
P-TYPE COULD BE MIXED OR IN SOLID FORM. WEAK HIGH PRES RETURNS FOR
MONDAY.
TEMPS ARE EXPECTED TO BE ABOVE NORMAL LEVELS THROUGH THE REMAINDER
OF THE PERIOD.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE CENTERED OVER THE GREAT LAKES REGION BUILDS SLOWLY
OVER THE TERMINALS THROUGH 00Z WEDNESDAY.
VFR THROUGH THE TAF PERIOD.
NORTH WINDS REMAIN SUSTAINED 15 TO 20 KT WITH GUSTS AROUND 25 KT
THROUGH THE OVERNIGHT. SUSTAINED WINDS AND GUSTS DIMINISH TOWARD 10Z
WITH GUSTS EXPECTED TO END 14Z TO 17Z. WINDS BACK TO NORTHWEST
DURING THE AFTERNOON...REMAINING MAINLY TO THE RIGHT OF 310 TRUE.
.OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
.TUESDAY NIGHT-FRIDAY...VFR.
.FRIDAY NIGHT...MVFR OR LOWER PROBABLE. E WINDS G15-20KT
POSSIBLE. WINTRY MIX POSSIBLE AT NORTHERN TERMINALS.
.SATURDAY...MVFR OR LESS POSSIBLE IN RAIN.
&&
.MARINE...
WIND GUSTS RUNNING HIGHER THAN EXPECTED. WITH LOW LEVEL WINDS
FORECAST TO INCREASE INTO THE OVERNIGHT HOURS...BEFORE DIMINISHING
TOWARDS SUNRISE...HAVE ISSUED A GALE WARNING FOR ALL WATERS
THROUGH 12Z.
THE WINDS WILL DECREASE ON TUESDAY AS THE PRESSURE GRADIENT
SLACKENS OVER THE REGION. WOULD EXPECT GUSTS TO 25-30 KT TO
CONTINUE OVER THE OCEAN WATERS/BAYS OF LONG ISLAND/EASTERN SOUND
INTO THE MORNING HOURS. SEAS SHOULD REMAIN ABOVE SCA LEVELS ON THE
COASTAL OCEAN WATERS INTO TUESDAY AFTERNOON...DEPENDING ON EXACTLY
HOW QUICKLY THE WINDS SUBSIDE.
TRANQUIL CONDITIONS ARE ANTICIPATED LATE TUESDAY THROUGH
WEDNESDAY.
SUB-ADVISORY CONDITIONS PREVAIL WED NIGHT THROUGH FRIDAY WITH A
WEAK PRES GRADIENT OVER THE AREA. WINDS AND SEAS WILL INCREASE FRI
NIGHT IN RESPONSE TO AN STRENGTHENING EASTERLY FLOW. WINDS SHOULD
SUBSIDE ON SAT...BUT SEAS ON THE OCEAN WILL LIKELY LINGER.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS FORECAST THROUGH FRIDAY. THE NEXT
CHANCE FOR RAIN IS FRIDAY NIGHT CONTINUING THROUGH SATURDAY.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR ANZ330-335-338-
340-345.
SMALL CRAFT ADVISORY UNTIL 4 PM EST TUESDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...MALOIT/PW/24
NEAR TERM...MALOIT
SHORT TERM...PW
LONG TERM...24
AVIATION...MET
MARINE...MALOIT/PW/24
HYDROLOGY...PW/24
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
937 AM EST SUN JAN 3 2016
.SYNOPSIS...
LOW PRESSURE JUST NORTHEAST OF THE GREAT LAKES WILL MOVE TO
THE CANADIAN MARITIMES BY LATE TODAY. ITS ASSOCIATED ARCTIC FRONT
WILL PUSH THROUGH OUR REGION THIS EVENING, BRINGING THE COLDEST
AIR OF THE WINTER SO FAR. HIGH PRESSURE WILL MOVE IN FOR MOST OF
THE UPCOMING WEEK AS TEMPERATURES SLOWLY MODERATE. A WARM FRONT
WILL THEN LIFT INTO OUR AREA LATE IN THE WEEK AS ANOTHER LOW MAY
APPROACH THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A COLD START TO THE DAY WILL BE FOLLOWED BY MODERATION AHEAD OF AN
ARCTIC FRONT. A POTENT SHORT WAVE DIGGING FROM THE GREAT LAKES TO
THE NORTHEAST TODAY WILL HELP AMPLIFY AN UPPER-LEVEL TROUGH. THIS
FEATURE IS FORECAST TO SHARPEN UP WITH TIME THROUGH THE DAY. AS THIS
ALL UNFOLDS, LOW PRESSURE WILL TRACK FROM JUST NORTHEAST OF THE
GREAT LAKES REGION EARLY THIS MORNING TO THE CANADIAN MARITIMES BY
LATE IN THE DAY. AN ASSOCIATED ARCTIC FRONT WILL PUSH SOUTHEASTWARD
TOWARD OUR REGION. AHEAD OF IT, A SURFACE TROUGH IS ANTICIPATED TO
MOVE THROUGH OUR CWA THIS AFTERNOON ALLOWING FOR A WIND SHIFT.
PRIOR TO THE ARCTIC FRONTS ARRIVAL AND AS A SURFACE TROUGH ARRIVES,
THE FLOW BRIEFLY TURNS MORE WEST TO SOUTHWEST ALONG WITH SOME
WARMING IN THE LOW TO MID LEVELS. THIS WAA WILL BE SHORT IN
DURATION THOUGH, AND THE WATER VAPOR IMAGERY SHOWS NO CONNECTION
TO DEEPER MOISTURE. HOWEVER, ENOUGH WAA AT 850 MB NEAR THE EASTERN
GREAT LAKES AND SPREADING EASTWARD IS RESULTING IN A WEALTH OF
CLOUDINESS THERE. THIS CONTINUES TO SPREAD SOUTH AND EASTWARD
EARLY THIS MORNING. THE RAP 850 MB RELATIVE HUMIDITY FIELD HAS A
DECENT HANDLE CURRENTLY WITH THIS CLOUD MASS, AND IT BRINGS IT INTO
OUR WESTERN ZONES BY LATE THIS MORNING. AS A RESULT, WE BUMPED UP
THE CLOUD COVER MORE ACROSS THE WESTERN AREAS. FARTHER TO THE
SOUTH AND EAST, WE ARE THINKING THAT ENOUGH DOWNSLOPING MAY HELP
ERODE SOME OF THE INCOMING OR DEVELOPING STRATOCUMULUS. NO
PRECIPITATION IS ANTICIPATED WITH THE SURFACE TROUGH OR AHEAD OF
THE FRONT GIVEN THE LACK OF DEEPER MOISTURE.
AS THE BOUNDARY LAYER WARMS TODAY ENOUGH MIXING IS ANTICIPATED WHICH
WILL RESULT IN AN INCREASING BREEZE THROUGH THE DAY, AND IT WILL
BECOME A LITTLE GUSTY AT TIMES. AS FOR THE HIGH TEMPERATURES, WE
USED A MOS/CONTINUITY BLEND. THE 850 MB THERMAL TROUGH ARRIVES THIS
AFTERNOON FROM WEST TO EAST WITH SOME CAA STARTING TO DEVELOP,
HOWEVER MILDER TEMPERATURES ARE EXPECTED ESPECIALLY ALONG AND
SOUTH/EAST OF INTERSTATE 95.
ADJUSTED THE GRIDS TO BETTER REFLECT THE CURRENT TEMPERATURE AND
DEW POINT TRENDS BUT OVERALL THE FORECAST LOOKS TO BE RIGHT ON
TRACK.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
AN UPPER-LEVEL TROUGH IS FORECAST TO UNDERGO AMPLIFICATION TONIGHT
AS IT ARRIVES ACROSS THE EAST, AND THIS WILL PUSH AN ARCTIC FRONT TO
OUR SOUTH AND EAST. THIS WILL BE ACCOMPANIED BY STRONG SHORT WAVE
ENERGY, ALTHOUGH MUCH OF IT IS THE CHANNELIZED VARIETY. AS THIS
OCCURS, THE CAA WILL CONTINUE TO STRENGTHEN ACROSS THE AREA AND THIS
WILL DRIVE A COLDER AIRMASS OUR WAY. THE WINDS SHOULD SETTLE DOWN
SOME THIS EVENING, BEFORE SOME INCREASE OVERNIGHT DUE TO THE ARRIVAL
OF ADDITIONAL CAA.
SOME STRATOCUMULUS SHOULD OCCUR AT LEAST IN THE EVENING AS THE CAA
DEEPENS AND IN PARTICULAR ACROSS THE NORTHWEST ZONES, AND THEN WE
TURN TO LAKE EFFECT. THE FLOW TURNS MORE NORTHERLY AT 850 MB AND
THIS WOULD PUT MORE OF THE LAKE INDUCED CLOUDINESS TO OUR WEST. WE
DO HAVE THE ENTIRE SHARPENING UPPER-LEVEL TROUGH ARRIVING PLUS
CHANNELIZED VORTICITY, HOWEVER THE AIRMASS SHOULD BE DRYING OVERALL
AS WELL. THEREFORE, WE PLACED SOMEWHAT HIGHER SKY COVER ACROSS THE
NORTHWEST AND WESTERN ZONES FOR A TIME. WE OPTED TO KEEP THE
FORECAST DRY AS WELL GIVEN THE 850 MB FLOW TURNING MORE FROM THE
NORTH WITH TIME.
AS FOR THE LOW TEMPERATURES, WE USED MOSTLY AN EVEN MOS/CONTINUITY
BLEND.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
THE EXTENDD STARTS OUT WITH A REMINDER OF WHAT WINTER FEELS LIKE
BEFORE TEMPS MODERATE BY THE END OF THE PD.
BEHIND AN ARCTIC FRONT, TEMPS WILL STRUGGLE TO MAKE IT OUT OF THE
30S ON MON, WITH NRN AND WRN AREAS NOT MAKING IT ABV 30 DEGREES.
TUESDAY WILL BE A TAD WARMER IN SOME LOCATIONS, AND A TAD COOLER
IN OTHERS, BUT MON NIGHT IS GOING TO BE THE COLDEST NIGHT OF THE
WINTER, BY FAR, ACROSS THE AREA. GRANTED, THAT IS A LOW BAR TO
CLEAR DUE TO THE WARMTH OF DECEMBER, BUT MOST LOCATIONS WILL BE IN
THE TEENS WITH SINGLE DIGITS N AND W.
HIGH PRES WILL OCCUPY THE MIDDLE PORTION OF THE NATION ERLY IN
THE WEEK AND WE WILL HAVE A GUSTY N TO NW FLOW, WHICH WILL MAKE
THINGS FEEL EVEN COLDER. BY THE MIDDLE OF THE WEEK, THE HIGH WILL
MOVE EWD, AND TEMPS WILL BEGIN TO WARM UP. CLIMATOLOGICAL NRMLS
ARE ONLY IN THE 30S TO LWR 40S THIS TIME OF YEAR AND WE WILL BE
BACK TO NRML BY MIDWEEK AND ABV NRML IN RETURN SLY FLOW BY THE END
OF THE PD.
AS THE HIGH MOVES EWD, A LEESIDE LOW WILL DEVELOP AND EJECT INTO
THE CNTRL PLAINS BY THU. THIS LOW WILL MOVE EWD, THEN NEWD. ITS
ASSOCD WM FNT WILL CROSS THE AREA FRI NIGHT OR SAT. PRECIP WILL
PRECEDE THE FRONT AS ERLY AS FRI. DEPENDING ON TEMPS AND TIMING,
THE PRECIP COULD BEGIN AS THE WINTRY VARIETY, ESPECIALLY N AND W,
BEFORE TEMPS WARM AND CHANGE EVERYTHING TO RAIN BEFORE THEM
STEADIER PRECIP MOVES IN LATER FRI. PRECIP WILL CONTINUE INTO SAT,
AND SHOULD BE WARM ENOUGH TO BE ALL RAIN EVERYWHERE, WITH THE PSBL
EXCEPTION OF THE EXTREME NW.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR WITH SCATTERED CLOUD COVERAGE DEVELOPING WITH BASES
BETWEEN 3500-5000 FEET. A CEILING SHOULD DEVELOP MOSTLY AT KABE
AND KRDG FOR A TIME LATER THIS MORNING AND THIS AFTERNOON.
SOUTHWEST TO WEST WINDS INCREASE TO 10-15 KNOTS STARTING AROUND
15Z WITH GUSTS TO 20 KNOTS, TURNING NORTHWEST IN THE AFTERNOON.
TONIGHT...VFR. NORTHWEST WINDS SHOULD DROP BELOW 10 KNOTS FOR
AWHILE, THEN SOME INCREASE IS ANTICIPATED LATE.
OUTLOOK...
MON AND MON NIGHT...A FEW FLURRIES MAY RESULT IN BRIEF MVFR
CONDITIONS, OTHERWISE VFR CONDITIONS EXPECTED. GUSTY
NORTHWEST WINDS 15 TO 20 KT WITH GUSTS TO 30 KT. HIGH CONFIDENCE.
TUE THROUGH THU...VFR. HIGH PRES. HIGH CONFIDENCE.
&&
.MARINE...
THE AIRMASS MODIFIES SOME TODAY AHEAD OF AN ARCTIC FRONT. THIS WILL
ALLOW SOUTHWESTERLY WINDS FOR A TIME BEFORE TURNING WEST TO
NORTHWEST THROUGH TONIGHT. SOME INCREASE TODAY IS ANTICIPATED
ESPECIALLY ACROSS THE NORTHERN ATLANTIC COASTAL WATERS. WE AWAIT THE
CAA TO DEVELOP LATE THIS AFTERNOON AND ESPECIALLY DURING TONIGHT IN
THE WAKE OF AN ARCTIC FRONT. THE STRONGEST CAA LOOKS TO DEVELOP
LATER TONIGHT, AND THIS IS WHEN THE WINDS ARE ANTICIPATED TO RAMP UP
MORE. WE ARE ANTICIPATING GUSTS OF 25-30 KNOTS AT TIMES THROUGH
TONIGHT, WITH MORE FREQUENCY LATER TONIGHT. THE FLOW TURNING MORE
NORTHWEST TONIGHT SHOULD ALSO HELP FAVOR SOME FUNNELING DOWN
DELAWARE BAY, THEREFORE A SMALL CRAFT ADVISORY STARTS AT MIDNIGHT
TONIGHT. THE ADVISORY REMAINS AS IS FOR THE REST OF THE ZONES,
HOWEVER THERE WILL BE A PERIOD ESPECIALLY TODAY WHERE CONDITIONS
ARE BELOW CRITERIA.
OUTLOOK...
MON AND MON NIGHT...NWLY WIND WILL INCREASE DUG THE DAY AND
SCA FLAGS ARE ANTICIPATED. BY MONDAY EVENING, GUSTS MAY APPROACH
GALE AND WILL CONTINUE TO MONITOR FOR GALE HEADLINES. SEAS WILL
SUBSEQUENTLY INCREASE TO NEAR OR JUST ABOVE 5 FT.
TUE...WIND WILL SUBSIDE THROUGH THE DAY AND SHOULD DROP BELOW SCA
CRITERIA BY LATE AFTN. HOWEVER SEAS WILL REMAIN ELEVATED ON THE
OCEAN AND SCA FLAGS SHUD STILL BE NEEDED FOR MUCH OF THE DAY.
TUE NIGHT THRU THU...NO MARINE HEADLINES ANTICIPATED.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 7 AM EST TUESDAY
FOR ANZ430-431.
&&
$$
SYNOPSIS...NIERENBERG
NEAR TERM...GORSE/MEOLA
SHORT TERM...GORSE
LONG TERM...NIERENBERG
AVIATION...GORSE/NIERENBERG
MARINE...GORSE/NIERENBERG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
601 AM EST SUN JAN 3 2016
.SYNOPSIS...
LOW PRESSURE JUST NORTHEAST OF THE GREAT LAKES WILL MOVE TO
THE CANADIAN MARITIMES BY LATE TODAY. ITS ASSOCIATED ARCTIC FRONT
WILL PUSH THROUGH OUR REGION THIS EVENING, BRINGING THE COLDEST
AIR OF THE WINTER SO FAR. HIGH PRESSURE WILL MOVE IN FOR MOST OF
THE UPCOMING WEEK AS TEMPERATURES SLOWLY MODERATE. A WARM FRONT
WILL THEN LIFT INTO OUR AREA LATE IN THE WEEK AS ANOTHER LOW MAY
APPROACH THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A COLD START TO THE DAY WILL BE FOLLOWED BY MODERATION AHEAD OF AN
ARCTIC FRONT. A POTENT SHORT WAVE DIGGING FROM THE GREAT LAKES TO
THE NORTHEAST TODAY WILL HELP AMPLIFY AN UPPER-LEVEL TROUGH. THIS
FEATURE IS FORECAST TO SHARPEN UP WITH TIME THROUGH THE DAY. AS THIS
ALL UNFOLDS, LOW PRESSURE WILL TRACK FROM JUST NORTHEAST OF THE
GREAT LAKES REGION EARLY THIS MORNING TO THE CANADIAN MARITIMES BY
LATE IN THE DAY. AN ASSOCIATED ARCTIC FRONT WILL PUSH SOUTHEASTWARD
TOWARD OUR REGION. AHEAD OF IT, A SURFACE TROUGH IS ANTICIPATED TO
MOVE THROUGH OUR CWA THIS AFTERNOON ALLOWING FOR A WIND SHIFT.
PRIOR TO THE ARCTIC FRONTS ARRIVAL AND AS A SURFACE TROUGH ARRIVES,
THE FLOW BRIEFLY TURNS MORE WEST TO SOUTHWEST ALONG WITH SOME
WARMING IN THE LOW TO MID LEVELS. THIS WAA WILL BE SHORT IN
DURATION THOUGH, AND THE WATER VAPOR IMAGERY SHOWS NO CONNECTION
TO DEEPER MOISTURE. HOWEVER, ENOUGH WAA AT 850 MB NEAR THE EASTERN
GREAT LAKES AND SPREADING EASTWARD IS RESULTING IN A WEALTH OF
CLOUDINESS THERE. THIS CONTINUES TO SPREAD SOUTH AND EASTWARD
EARLY THIS MORNING. THE RAP 850 MB RELATIVE HUMIDITY FIELD HAS A
DECENT HANDLE CURRENTLY WITH THIS CLOUD MASS, AND IT BRINGS IT INTO
OUR WESTERN ZONES BY LATE THIS MORNING. AS A RESULT, WE BUMPED UP
THE CLOUD COVER MORE ACROSS THE WESTERN AREAS. FARTHER TO THE
SOUTH AND EAST, WE ARE THINKING THAT ENOUGH DOWNSLOPING MAY HELP
ERODE SOME OF THE INCOMING OR DEVELOPING STRATOCUMULUS. NO
PRECIPITATION IS ANTICIPATED WITH THE SURFACE TROUGH OR AHEAD OF
THE FRONT GIVEN THE LACK OF DEEPER MOISTURE.
AS THE BOUNDARY LAYER WARMS TODAY ENOUGH MIXING IS ANTICIPATED WHICH
WILL RESULT IN AN INCREASING BREEZE THROUGH THE DAY, AND IT WILL
BECOME A LITTLE GUSTY AT TIMES. AS FOR THE HIGH TEMPERATURES, WE
USED A MOS/CONTINUITY BLEND. THE 850 MB THERMAL TROUGH ARRIVES THIS
AFTERNOON FROM WEST TO EAST WITH SOME CAA STARTING TO DEVELOP,
HOWEVER MILDER TEMPERATURES ARE EXPECTED ESPECIALLY ALONG AND
SOUTH/EAST OF INTERSTATE 95. THE HOURLY TEMPERATURE AND DEW POINT
GRIDS EARLY THIS MORNING ARE BEING ADJUSTED WITH THE LATEST
OBSERVATIONS, THEN THE LAMP/LAV GUIDANCE IS BLENDED IN TO HELP
ASSIST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
AN UPPER-LEVEL TROUGH IS FORECAST TO UNDERGO AMPLIFICATION TONIGHT
AS IT ARRIVES ACROSS THE EAST, AND THIS WILL PUSH AN ARCTIC FRONT TO
OUR SOUTH AND EAST. THIS WILL BE ACCOMPANIED BY STRONG SHORT WAVE
ENERGY, ALTHOUGH MUCH OF IT IS THE CHANNELIZED VARIETY. AS THIS
OCCURS, THE CAA WILL CONTINUE TO STRENGTHEN ACROSS THE AREA AND THIS
WILL DRIVE A COLDER AIRMASS OUR WAY. THE WINDS SHOULD SETTLE DOWN
SOME THIS EVENING, BEFORE SOME INCREASE OVERNIGHT DUE TO THE ARRIVAL
OF ADDITIONAL CAA.
SOME STRATOCUMULUS SHOULD OCCUR AT LEAST IN THE EVENING AS THE CAA
DEEPENS AND IN PARTICULAR ACROSS THE NORTHWEST ZONES, AND THEN WE
TURN TO LAKE EFFECT. THE FLOW TURNS MORE NORTHERLY AT 850 MB AND
THIS WOULD PUT MORE OF THE LAKE INDUCED CLOUDINESS TO OUR WEST. WE
DO HAVE THE ENTIRE SHARPENING UPPER-LEVEL TROUGH ARRIVING PLUS
CHANNELIZED VORTICITY, HOWEVER THE AIRMASS SHOULD BE DRYING OVERALL
AS WELL. THEREFORE, WE PLACED SOMEWHAT HIGHER SKY COVER ACROSS THE
NORTHWEST AND WESTERN ZONES FOR A TIME. WE OPTED TO KEEP THE
FORECAST DRY AS WELL GIVEN THE 850 MB FLOW TURNING MORE FROM THE
NORTH WITH TIME.
AS FOR THE LOW TEMPERATURES, WE USED MOSTLY AN EVEN MOS/CONTINUITY
BLEND.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
THE EXTENDD STARTS OUT WITH A REMINDER OF WHAT WINTER FEELS LIKE
BEFORE TEMPS MODERATE BY THE END OF THE PD.
BEHIND AN ARCTIC FRONT, TEMPS WILL STRUGGLE TO MAKE IT OUT OF THE
30S ON MON, WITH NRN AND WRN AREAS NOT MAKING IT ABV 30 DEGREES.
TUESDAY WILL BE A TAD WARMER IN SOME LOCATIONS, AND A TAD COOLER
IN OTHERS, BUT MON NIGHT IS GOING TO BE THE COLDEST NIGHT OF THE
WINTER, BY FAR, ACROSS THE AREA. GRANTED, THAT IS A LOW BAR TO
CLEAR DUE TO THE WARMTH OF DECEMBER, BUT MOST LOCATIONS WILL BE IN
THE TEENS WITH SINGLE DIGITS N AND W.
HIGH PRES WILL OCCUPY THE MIDDLE PORTION OF THE NATION ERLY IN
THE WEEK AND WE WILL HAVE A GUSTY N TO NW FLOW, WHICH WILL MAKE
THINGS FEEL EVEN COLDER. BY THE MIDDLE OF THE WEEK, THE HIGH WILL
MOVE EWD, AND TEMPS WILL BEGIN TO WARM UP. CLIMATOLOGICAL NRMLS
ARE ONLY IN THE 30S TO LWR 40S THIS TIME OF YEAR AND WE WILL BE
BACK TO NRML BY MIDWEEK AND ABV NRML IN RETURN SLY FLOW BY THE END
OF THE PD.
AS THE HIGH MOVES EWD, A LEESIDE LOW WILL DEVELOP AND EJECT INTO
THE CNTRL PLAINS BY THU. THIS LOW WILL MOVE EWD, THEN NEWD. ITS
ASSOCD WM FNT WILL CROSS THE AREA FRI NIGHT OR SAT. PRECIP WILL
PRECEDE THE FRONT AS ERLY AS FRI. DEPENDING ON TEMPS AND TIMING,
THE PRECIP COULD BEGIN AS THE WINTRY VARIETY, ESPECIALLY N AND W,
BEFORE TEMPS WARM AND CHANGE EVERYTHING TO RAIN BEFORE THEM
STEADIER PRECIP MOVES IN LATER FRI. PRECIP WILL CONTINUE INTO SAT,
AND SHOULD BE WARM ENOUGH TO BE ALL RAIN EVERYWHERE, WITH THE PSBL
EXCEPTION OF THE EXTREME NW.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR WITH SCATTERED CLOUD COVERAGE DEVELOPING WITH BASES
BETWEEN 3500-5000 FEET. A CEILING SHOULD DEVELOP MOSTLY AT KABE
AND KRDG FOR A TIME LATER THIS MORNING AND THIS AFTERNOON.
SOUTHWEST TO WEST WINDS INCREASE TO 10-15 KNOTS STARTING AROUND
15Z WITH GUSTS TO 20 KNOTS, TURNING NORTHWEST IN THE AFTERNOON.
TONIGHT...VFR. NORTHWEST WINDS SHOULD DROP BELOW 10 KNOTS FOR
AWHILE, THEN SOME INCREASE IS ANTICIPATED LATE.
OUTLOOK...
MON AND MON NIGHT...A FEW FLURRIES MAY RESULT IN BRIEF MVFR
CONDITIONS, OTHERWISE VFR CONDITIONS EXPECTED. GUSTY
NORTHWEST WINDS 15 TO 20 KT WITH GUSTS TO 30 KT. HIGH CONFIDENCE.
TUE THROUGH THU...VFR. HIGH PRES. HIGH CONFIDENCE.
&&
.MARINE...
THE AIRMASS MODIFIES SOME TODAY AHEAD OF AN ARCTIC FRONT. THIS WILL
ALLOW SOUTHWESTERLY WINDS FOR A TIME BEFORE TURNING WEST TO
NORTHWEST THROUGH TONIGHT. SOME INCREASE TODAY IS ANTICIPATED
ESPECIALLY ACROSS THE NORTHERN ATLANTIC COASTAL WATERS. WE AWAIT THE
CAA TO DEVELOP LATE THIS AFTERNOON AND ESPECIALLY DURING TONIGHT IN
THE WAKE OF AN ARCTIC FRONT. THE STRONGEST CAA LOOKS TO DEVELOP
LATER TONIGHT, AND THIS IS WHEN THE WINDS ARE ANTICIPATED TO RAMP UP
MORE. WE ARE ANTICIPATING GUSTS OF 25-30 KNOTS AT TIMES THROUGH
TONIGHT, WITH MORE FREQUENCY LATER TONIGHT. THE FLOW TURNING MORE
NORTHWEST TONIGHT SHOULD ALSO HELP FAVOR SOME FUNNELING DOWN
DELAWARE BAY, THEREFORE A SMALL CRAFT ADVISORY STARTS AT MIDNIGHT
TONIGHT. THE ADVISORY REMAINS AS IS FOR THE REST OF THE ZONES,
HOWEVER THERE WILL BE A PERIOD ESPECIALLY TODAY WHERE CONDITIONS
ARE BELOW CRITERIA.
OUTLOOK...
MON AND MON NIGHT...NWLY WIND WILL INCREASE DUG THE DAY AND
SCA FLAGS ARE ANTICIPATED. BY MONDAY EVENING, GUSTS MAY APPROACH
GALE AND WILL CONTINUE TO MONITOR FOR GALE HEADLINES. SEAS WILL
SUBSEQUENTLY INCREASE TO NEAR OR JUST ABOVE 5 FT.
TUE...WIND WILL SUBSIDE THROUGH THE DAY AND SHOULD DROP BELOW SCA
CRITERIA BY LATE AFTN. HOWEVER SEAS WILL REMAIN ELEVATED ON THE
OCEAN AND SCA FLAGS SHUD STILL BE NEEDED FOR MUCH OF THE DAY.
TUE NIGHT THRU THU...NO MARINE HEADLINES ANTICIPATED.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 7 AM EST TUESDAY
FOR ANZ430-431.
&&
$$
SYNOPSIS...NIERENBERG
NEAR TERM...GORSE
SHORT TERM...GORSE
LONG TERM...NIERENBERG
AVIATION...GORSE/NIERENBERG
MARINE...GORSE/NIERENBERG
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
400 PM EST SUN JAN 3 2016
.DISCUSSION...
CURRENTLY...
MID LEVEL SHORT WAVE TROUGH AXIS OVER THE CTRL GULF COAST/NORTHERN
GOMEX HAS BACKED THE H85-50 FLOW TO SWRLY NORTH OF THE STALLED FRONT
TO OUR SOUTH. ADDITIONAL FORCED ASCENT BEING PROVIDED BY RR QUAD OF
DEPARTING 110-130KT JET STREAK ACROSS THE SE ATLC COASTAL STATES...
WITH LF QUAD OF APPROACHING JET PUSHING TOWARD THE N-CTRL/NE GOMEX.
TWO LARGE SW-NE ORIENTED SWATHS OF LIGHT-MDT RAIN HAVE OVERSPREAD
THE FAR NORTHERN AND CENTRAL-SOUTHERN CWA...WITH VERY LIGHT RETURNS
(SPRINKLES) ON EITHER SIDE OF THESE TWO FEATURES. OTRW...SKIES OVC
WITH TEMPS PRETTY MUCH RIGHT WHERE THEY WERE THIS MORNING.
THROUGH TONIGHT...
MID LEVEL TROUGH SLIDES E AND THEN TURNS ENE AS IT MOVES OFFSHORE
INTO THE ATLC. THIS WILL SPIN UP SURFACE LOW NE OF THE BAHAMAS ALONG
THE STALLED FRONT...AND BEGIN TO DRAG DRIER AIR INTO THE NRN-CTRL
CWA LATE TONIGHT. UNTIL THEN...PERIODS OF RAIN WILL CONTINUE FROM
LATE AFTERNOON WELL INTO THE EVENING/OVERNIGHT WITH ACTIVITY
SHIFTING E/S AND TAPERING OFF OR ENDING LATE. EVEN WITH ALL THE
CLOUDS/RAIN...TEMPS LOOK QUITE CHILLY TOWARD SUNRISE MONDAY WITH
MINS PROGGED TO DROP BELOW 50F N/W OF FORT DRUM-KMLB LINE. L-M40S NW
OF I-4...MAINLY L-M50S TO THE S/E.
MONDAY...
COOL DAY ON TAP WITH TEMPS SLOWLY RISING INTO/THROUGH THE 50S AND
ONLY REACHING THE L60S NORTH TO MID 60S SOUTH UNDER RAPIDLY CLEARING
SKIES (WITH SOME LINGERING HIGH CLOUDS) AND A NW BREEZE OF 10-15MPH.
MAYBE A FEW LINGERING SPRINKLES OVER THE FAR SOUTH IN THE
MORNING...BUT JUST ABOUT ALL THE PRECIP WILL BE LONG GONE BY THEN.
00Z TUE - 12Z WED...
A PREVAILING ZONAL FLOW PATTERN IN THE H30-H20 LYR WILL PUSH A
STRONG HI PRES RIDGE DIVING OUT OF THE NRN PLAINS E OF THE MS RIVER
VALLEY ON TUE...THEN OFF THE ERN SEABOARD BY DAYBREAK WED. H100-H85
FLOW WILL RESPOND BY VEERING STEADILY FROM N/NW MON NIGHT TO DUE E
BY DAYBREAK WED.
CENTER OF THE RIDGE AXIS WILL TRACK FROM THE NRN PLAINS ACRS THE OH
RIVER VALLEY THRU TUE...THEN OFF THE MID ATLC COAST BY 12Z WED.
BECAUSE OF ITS RAPID MOVEMENT...THE N/NWRLY FLOW ACRS THE FL
PENINSULA WILL NOT PREVAIL LONG ENOUGH FOR IT TO SCOUR OUT POST
FRONTAL MOISTURE FROM THE H100-H85 LYR LINGERING OVER THE W ATLC. AS
SUCH...AS WINDS VEER TO A BRISK...ALBEIT RELATIVELY SHALLOW...
ONSHORE FLOW...THIS MOISTURE WILL PUSH BACK INTO CENTRAL FL AFT
DAYBREAK TUE. THE RIDGE WILL MAINTAIN A STRONG SUBSIDENCE INVERSION
THRU THE H85-H70 LYR THAT WILL PRECLUDE DEEP CONVECTION...BUT THERE
WILL BE A SLGT CHC OF COASTAL SHRA ACTIVITY WILL IS EXPECTED ON
TUE...BCMG ISOLD/SCT AREAWIDE TUE NIGHT.
SHALLOW COLD AIR ADVECTION PATTERN MON NIGHT WILL RESULT IN MIN
TEMPS DROPPING INTO THE L/M40S ACRS THE INTERIOR. THE ONSHORE WIND
SHIFT WILL BEGIN IN THE PREDAWN HRS TUE MRNG THAT WILL ALLOW SOME
OCEAN MODIFICATION OF THE COASTAL TEMPS WITH COASTAL MINS HOLDING IN
THE U40S/L50 N OF THE CAPE...AND IN THE M/U50S TO THE S. PATTERN
WILL CONT THRU THE DAY TUE AS WINDS SLOWLY VEER THRU NE...MAX TEMPS
IN THE L/M60S ALONG AN N OF THE I-4 CORRIDOR...U60S/L70S TO THE S.
PREVAILING ONSHORE FLOW TUE NIGHT WILL KEEP MIN TEMPS NOTICEABLY
WARMER FROM MON NIGHT...L/M50S INTERIOR...M/U50S FROM THE CAPE
NWD...L/M60S TREASURE COAST.
WED-SAT...(PREV DISC)
RATHER STRONG ERN CONUS HIGH PRESSURE RIDGE EXPANDS AND SHIFTS EWD
OVER THE WRN ATLC THROUGH WED NIGHT. MODEL TIMING AND INTENSITY
DIFFS START TO SHOW UP THU WITH NEXT FAST MOVING SHORT WAVE TROUGH
IN THE DEVELOPING (ENSO ANTICIPATED) ENERGETIC PATTERN OVER THE SRN
TIER OF THE CONUS.
LTST GUID FROM 00Z SHOWS THE GULF WAVE IN A VARYING DEGREE OF SFC
DEVELOPMENT OVER THE EASTERN GULF LATE THU/EARLY FRI WITH THE ECM
MOST ENERGETIC WITH FEATURE AS IS APCHS THE STATE. GIVEN A MORE
OPEN/WEAKER PORTRAYAL CONTINUES WITH GFS IN THIS TIME PERIOD A LACK
OF CONSENSUS WL PRECLUDE THUNDER MENTION ATTM. HOWEVER NOTEWORTHY
THAT RAIN CHCS SHOULD REMAIN IN THE SCT CATEGORY WITH THE GENERAL
INFLUENCE OF UPR WAVE ALONG WITH INFLUENCE OF SOUTHERN STREAM AND
AVBL MOISTURE INTO THE WEEKEND.
&&
.AVIATION...NOSIG CHGS TO THE MORNING DISC. IFR-NEAR IFR CIGS OVC-
BKN008-013. AS ANTICIPATED...CIGS HAVE LOWERED TO AROUND OVC012-15
FROM VRB-SUA. OCNL MVFR VSBYS IN -RABR WITH SPOTTY IFR NEAR 2SM IN
MODERATE RAIN. CONDITIONS TO GRADUALLY IMPROVE FROM N/W TO S/E
STARTING ABOUT 04Z-06Z. LOWER CIGS CLEARING OUT OF MLB-SUA 12Z-16Z.
&&
.MARINE...
TONIGHT/MON...NOSIG CHGS TO THE ONGOING FCST OR ADVISORY. 12Z NWPS
LOOKED TOO HIGH GIVEN THE FCST WINDS A LITTLE EITHER SIDE OF
20KT...SO WENT WITH A BLEND WHICH KEPT PEAK SEAS AROUND 7FT THRU
MONDAY AFTERNOON...WITH A BRIEF PERIOD OF 7-8FT SEAS IN THE GULF
STREAM OVERNIGHT. WINDS/SEAS WILL AT BEST BARELY MEET SCA CRITERIA
OVER THE OUTER PORTION OF THE 0-20NM LEGS THROUGH OVERNIGHT...BUT
GIVEN THE SHORT PERIOD CHOP AND INCREASING TREND IN WINDS FCST JUST
BEYOND THE SHORT RANGE...WILL LEAVE IT IN PLACE.
TUE-WED...STRONG HI PRES RIDGE DIVING OUT OF THE NRN PLAINS WILL
BECOME ENTRAINED IN STRONG UPR LVL ZONAL FLOW THAT WILL PUSH IT OFF
THE ERN SEABOARD THRU MIDWEEK. TIGHT PGRAD ACRS THE LCL ATLC WILL
MAINTAIN A MODERATE TO FRESH NERLY BREEZE THRU THE DAY TUE AS THE
RIDGE PASSES ACRS THE APPALACHIAN RANGE...VEERING TO AN ERLY BREEZE
ON WED AS IT MOVES INTO THE W ATLC. SEAS 5-7FT NEARSHORE AND 7-9FT
OFFSHORE.
THU-FRI...HI PRES WILL WEAKEN OVER THE W ATLC WHILE A WEAK SFC LOW
DVLPS NE OF THE BAHAMAS. PGRAD WILL LOOSEN...ALLOWING SFC/BNDRY LYR
WINDS TO DIMINISH TO A LIGHT TO GENTLE E/NE BREEZE ON THU...VEERING
TO A LIGHT TO GENTLE SRLY BREEZE THU NIGHT/FRI...THEN BCMG A GENTLE
TO MODERATE S/SWRLY BREEZE FRI NIGHT. ERLY SWELLS WILL ENHANCE THE
LCL WIND WAVES...KEEPING SEAS 5-7FT NEARSHORE AND 6-8FT OFFSHORE ON
THU. SEAS SUBSIDING TO 4-5FT NEARSHORE AND 5-6FT OFFSHORE THRU
SUNSET FRI AS THE DVLPG SW FLOW GRADUALLY BEATS DOWN THE SWELL.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 46 62 49 62 / 90 0 10 20
MCO 45 64 46 66 / 100 0 0 10
MLB 48 64 55 67 / 100 10 10 20
VRB 52 64 56 69 / 100 10 10 20
LEE 42 63 42 64 / 90 0 0 10
SFB 43 63 44 64 / 90 0 0 10
ORL 46 63 46 66 / 100 0 0 10
FPR 53 64 56 69 / 100 10 10 20
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 4 AM EST WEDNESDAY FOR FLAGLER BEACH
TO VOLUSIA-BREVARD COUNTY LINE 0-20 NM-FLAGLER BEACH TO
VOLUSIA-BREVARD COUNTY LINE 20-60 NM-VOLUSIA-BREVARD COUNTY
LINE TO SEBASTIAN INLET 0-20 NM-VOLUSIA-BREVARD COUNTY LINE
TO SEBASTIAN INLET 20-60 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM EST WEDNESDAY FOR SEBASTIAN
INLET TO JUPITER INLET 0-20 NM-SEBASTIAN INLET TO JUPITER
INLET 20-60 NM.
&&
$$
SHORT TERM/AVIATION...CRISTALDI
LONG TERM/IMPACT WX...BRAGAW
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
247 PM EST SUN JAN 3 2016
.SYNOPSIS...
19Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A COMPLEX UPPER LEVEL
PATTERN OVER THE CONUS. WV IMAGERY SHOWS A CLOSED LOW FEATURE OVER
THE PACIFIC NORTHWEST...WITH A BROAD BAND OF DEEP MOISTURE
ARRIVING OVER THE OREGON/CALIFORNIA COASTS. FURTHER DOWNSTREAM WE
FIND AN AMPLIFYING NORTHERN STREAM TROUGH OVER THE GREAT LAKES/NEW
ENGLAND STATES. THE FEATURE THAT WILL PLAY THE BIGGEST ROLE IN OUR
SHORT TERM FORECAST IS AN ACTIVE SOUTHERN STREAM CROSSING THE GULF
OF MEXICO AND OVER THE FLORIDA PENINSULA. A FAIRLY STRONG
MID/UPPER LEVEL SHORTWAVE IS CURRENTLY EJECTING ACROSS THE CENTRAL
GULF OF MEXICO...AND WILL BE ARRIVING OVERHEAD LATER TONIGHT.
SYNOPTIC FORCING FOR ASCENT AHEAD OF THIS ENERGY HAS ARRIVED OVER
THE FLORIDA PENINSULA AND MUCH OF THE AREA CAN EXPECT A WET LATE
AFTERNOON/EVENING PERIOD.
AT THE SURFACE WE FIND AN ANAFRONT QUASI-STATIONARY FRONTAL
BOUNDARY OVER FAR SOUTH FLORIDA/FLORIDA STRAITS...WITH A TRAILING
REGION OF HIGH PRESSURE DROPPING SOUTH ACROSS THE PLAINS STATES.
THE TERM ANAFRONT IS USED FOR FRONTAL BOUNDARIES WHEN THE FORCING
ASSOCIATED WITH THE FRONT RESULTS IN THE MAIN CLOUD/PRECIP SHIELD
DEVELOPS WITHIN THE POST FRONTAL ENVIRONMENT (THE COOL SIDE OF
THE FRONT). KATAFRONT CONFIGURATION IS THE ONE WE SEE MORE
OFTEN...WHERE A BAND OF SHOWERS AND STORMS CROSSES AHEAD OF THE
FRONT...AND THINGS CLEAR OUT BEHIND THE BOUNDARY.
RAINFALL HAS FILLED IN ACROSS THE REGION IN PAST COUPLE OF HOURS.
THE I-4 CORRIDOR WAS CURIOUSLY THE LAST PLACE TO SEE THE RAINFALL
ARRIVE...AS ORGANIZED BANDS OF RAIN ORGANIZED OVER THE NATURE
COAST AND DOWN ACROSS THE SUNCOAST DURING THE PAST FEW HOURS.
HOWEVER...THE NEARING OF THE EARLIER MENTIONED SHORTWAVE ENERGY
ACROSS THE GULF...COMBINED WITH A FAVORABLE POSITION UNDER A
COUPLED JET STRUCTURE IS FINALLY OVERWHELMING ANY NEGATIVE
FACTORS.
THE OVERALL SYNOPTIC FORCING IS RATHER ROBUST OVER THE FORECAST
AREA INTO THE EVENING HOURS. ALTHOUGH THE NORTHERN EDGE OF THE
RAINFALL WILL BE SLOWLY DROPPING SOUTH...DEEP LAYER Q-VECTOR
CONVERGENCE REMAINS IMPRESSIVE FROM THE I-4 CORRIDOR SOUTHWARD
THROUGH AT LEAST EARLY EVENING....AND THIS WORKING IN TANDEM WITH
THE JET STREAK DIVERGENCE/DIFFLUENCE ALOFT SHOULD KEEP THE WEATHER
UNSETTLED.
TEMPERATURES STAY ON THE COOL SIDE THE REST OF THE AFTERNOON...
ESPECIALLY WHEN COMPARED TO HOW WARM DECEMBER WAS. NORTHERLY FLOW
BEHIND THE COLD FRONT IS DELIVERING A STEADY SUPPLY OF DRIER AIR
NEAR THE SURFACE. RAINFALL DESCENDING INTO THIS DRIER AIR WILL
CONTINUE TO UNDERGO EVAPORATIVE EFFECTS. METEOROLOGISTS CALL THIS
PROCESS THE "WET BULB EFFECT". THE MAIN INFLUENCE OF THE "WET BULB
EFFECT" IS TO COOL THE AIR VIA EVAPORATION DOWN TOWARD THE
DEWPOINT. WITH THE AIR HOLDING MORE AND MORE MOISTURE AS RAIN
EVAPORATES. THE DEWPOINT RISES AS THE TEMPERATURE DROPS. WHEN THE
TWO FINALLY MEET...THE AIR IS SATURATED...THE EVAPORATION PROCESS
ENDS...AND TEMPERATURES HOLD STEADY.
&&
.SHORT TERM (TONIGHT THROUGH MONDAY)...
RAIN WILL TAPER OFF TO THE NORTH OF THE I-4 CORRIDOR THIS
EVENING...AND THEN TAPER OFF FOR THE SOUTHERN HALF OF THE
FORECAST AREA OVERNIGHT. EXCELLENT AGREEMENT AMONG THE GUIDANCE
MEMBERS THAT THE FORCING AHEAD OF THE SHORTWAVE WILL EXIT TO OUR
EAST BY SUNRISE MONDAY MORNING. A REINFORCING SHOT OF COOL AND DRY
AIR WILL BE WORKING SOUTH ACROSS THE PENINSULA IN THE WAKE OF THIS
SYSTEM DURING THE SECOND HALF OF THE NIGHT. THE LAST OF THE
RAIN/SHOWERS SHOULD EXIT DURING THE EARLY MORNING HOURS DOWN BY THE
FORT MYERS AREA. FORECASTING A RATHER CHILLY NIGHT...WITH LOW
TEMPS BY SUNRISE RANGING FROM THE UPPER 30S AROUND CHIEFLAND...TO
THE 40S ACROSS THE I-4 CORRIDOR...TO THE LOWER/MIDDLE 50S DOWN BY
CHARLOTTE AND LEE COUNTIES.
DEEP MOISTURE CONTINUES TO BE SCOURED OUT DURING THE DAY ON
MONDAY...AND SHOULD SEE A FAIR AMOUNT OF SUNSHINE AND TEMPERATURES
CLIMBING INTO THE 60S. PW VALUES DROP FROM AROUND 1.5" THIS
AFTERNOON ACROSS THE REGION TO WELL BELOW ONE INCH REGION-WIDE BY
MONDAY AFTERNOON. WILL HAVE TO KEEP ANY EYE ON THE POTENTIAL FOR
SOME LOW LEVEL STATOCU MIGRATING OFF THE GULF IN THE NW FLOW
MONDAY MORNING...HOWEVER DOES APPEAR THAT THE LOW COLUMN TEMPS
WILL BE A BIT TOO WARM TO RESULT IN WIDESPREAD LOW CLOUD
DEVELOPMENT...AND CERTAINLY TOO WARM TO SUPPORT ANY INSTABILITY
SPRINKLES MOVING ASHORE.
&&
.LONG TERM (MONDAY NIGHT-SUNDAY)...
FOR MONDAY NIGHT INTO TUESDAY...AN UPPER-LEVEL TROUGH WILL SHIFT
OVER THE WESTERN ATLANTIC AS MID-LEVEL RIDGING BEGINS TO BUILD OVER
THE SOUTHEAST. AT THE SURFACE...AN AREA OF HIGH PRESSURE WILL
DOMINATE THE EASTERN PORTION OF THE COUNTRY...WITH COOL AND DRY
CONDITIONS FOR THE FORECAST AREA. TEMPERATURES WILL RUN FROM THE
UPPER 50S ACROSS THE NATURE COAST TO AROUND 70 ACROSS SOUTHWEST
FLORIDA.
A SERIES OF SHORTWAVES ARE FORECAST TO MOVE ACROSS THE REGION
WEDNESDAY AND THURSDAY...WITH THE SURFACE HIGH SHIFTING EASTWARD
OVER THE WESTERN ATLANTIC. WILL KEEP A CHANCE FOR SHOWERS IN THE
FORECAST FOR BOTH DAYS WITH FLOW OFF THE ATLANTIC...AND HIGHS WILL
WARM BY A FEW DEGREES EACH DAY.
AN UPPER-LEVEL LOW WILL SHIFT NORTHEAST TOWARD THE GREAT LAKES
REGION ON FRIDAY WITH A FRONTAL BOUNDARY MOVING INTO THE SOUTHEAST
AND A WEAK AREA OF LOW PRESSURE TRYING TO FORM IN THE GULF. THIS
WILL KEEP A CHANCE FOR SHOWERS IN THE FORECAST...ESPECIALLY FOR THE
WESTERN PART OF THE FORECAST AREA. CONDITIONS WILL BE RATHER WARM
AND HUMID AHEAD OF THE FRONT WITH TEMPERATURES IN THE MID TO UPPER
70S.
ANOTHER SHORTWAVE WILL MOVE ACROSS THE SOUTHERN PART OF THE COUNTRY
SATURDAY AND SATURDAY NIGHT...WITH GLOBAL MODELS DEPICTING A SURFACE
LOW DEVELOPING SOMEWHERE ALONG THE NORTHERN GULF COAST REGION OR
CENTRAL GULF AND THEN MOVING ACROSS THE FLORIDA BIG BEND INTO THE
SOUTHEAST. THIS WOULD GIVE US ANOTHER PERIOD OF UNSETTLED WEATHER
SATURDAY AND INTO SUNDAY MORNING...WITH CLEARING BY THE END OF
SUNDAY.
&&
.AVIATION...
WIDESPREAD RAIN/SHOWERS FOR ALL TERMINALS INTO THE EARLY EVENING
HOURS. RAIN THEN TAPERS OFF FROM NORTH TO SOUTH THIS EVENING AND
OVERNIGHT. WILL GO WITH GENERAL MVFR CONDITIONS INTO THE EVENING
HOURS...ALTHOUGH A FEW PERIODS OF IFR WILL BE POSSIBLE WITH
HEAVIER BOUTS OF RAIN. THE LAST OF THE SHOWERS SHOULD EXIT SOUTH
OF KFMY/KRSW DURING THE PRE-DAWN HOURS MONDAY. AN EXTENDED PERIOD
OF VFR CONDITIONS ARE THEN LIKELY FOR MONDAY INTO TUESDAY.
&&
.MARINE...
ELEVATED WINDS AND SEAS WILL BE IN PLACE THROUGH TUESDAY NIGHT IN
THE WAKE OF A DEPARTING COLD FRONT. AN EXTENDED PERIOD OF
CAUTIONARY LEVEL CONDITIONS IS EXPECTED...WITH PERIODS OF
ADVISORY LEVEL WINDS. A SMALL CRAFT ADVISORY WILL LIKELY BE
REQUIRED FOR MONDAY NIGHT INTO TUESDAY. THE GRADIENT DOES LOOK TO
BRIEFLY RELAX DURING THE SECOND HALF OF THE WEEK...BEFORE THE NEXT
FRONT APPROACHES THE EASTERN GULF EARLY NEXT WEEKEND.
&&
.FIRE WEATHER...
A WETTING RAINFALL FOR ALL AREAS UNDERWAY INTO THE EVENING HOURS.
RAIN THEN TAPERS OFF FROM NORTH TO SOUTH THIS EVENING AND
OVERNIGHT. DRIER AIR FILTERS IN FROM THE NORTH ON MONDAY...AND A
FEW INLAND LOCATIONS MAY BRIEFLY SEE RELATIVE HUMIDITY VALUES DROP
BELOW 35 PERCENT MONDAY AFTERNOON. FAIR WEATHER AND NO SIGNIFICANT
FIRE WEATHER CONCERNS ARE ANTICIPATED FOR TUESDAY.
FOG POTENTIAL...NO SIGNIFICANT AREA OF FOG OR REDUCED VISIBILITY
ARE EXPECTED THE NEXT SEVERAL NIGHTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 50 65 47 67 / 80 0 0 0
FMY 54 67 49 71 / 100 0 0 10
GIF 47 64 46 67 / 90 0 0 10
SRQ 54 65 49 70 / 90 0 0 0
BKV 44 63 40 65 / 60 0 0 10
SPG 53 64 51 66 / 90 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
LONG TERM/DECISION SUPPORT...CARLISLE
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
822 AM EST SUN JAN 3 2016
.UPDATE...
13Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A COMPLEX UPPER LEVEL
PATTERN OVER THE CONUS. WV IMAGERY SHOWS A CLOSED LOW FEATURE OVER
THE PACIFIC NORTHWEST...WITH A BROAD BAND OF DEEP MOISTURE
ARRIVING OVER THE OREGON/CALIFORNIA COASTS. FURTHER DOWNSTREAM WE
FIND AN AMPLIFYING NORTHERN STREAM TROUGH OVER THE GREAT
LAKES/NEW ENGLAND STATES. THE FEATURE THAT WILL PLAY THE BIGGEST
ROLE IN OUR SHORT TERM FORECAST IS AN ACTIVE SOUTHERN STREAM
CROSSING THE GULF OF MEXICO AND OVER THE FLORIDA PENINSULA. A
FAIRLY STRONG MID/UPPER LEVEL SHORTWAVE IS CURRENTLY EJECTING
ACROSS THE WESTERN/CENTRAL GULF OF MEXICO. THIS ENERGY WILL
QUICKLY MIGRATE EASTWARD WITH ITS ASSOCIATED HEIGHT FALLS TO
INCREASE THE LEVEL OF SYNOPTIC FORCING FOR LIFT OVER THE CENTRAL
AND SOUTHERN PENINSULA BY THE AFTERNOON HOURS.
AT THE SURFACE WE FIND AN ANAFRONT QUASI-STATIONARY FRONTAL
BOUNDARY OVER FAR SOUTH FLORIDA/FLORIDA STRAITS...WITH A TRAILING
REGION OF HIGH PRESSURE DROPPING SOUTH ACROSS THE PLAINS STATES.
THE TERM ANAFRONT IS USED FOR FRONTAL BOUNDARIES WHEN THE FORCING
ASSOCIATED WITH THE FRONT RESULTS IN THE MAIN CLOUD/PRECIP SHIELD
DEVELOPS WITHIN THE POST FRONTAL ENVIRONMENT (THE COOL SIDE OF
THE FRONT). KATAFRONT CONFIGURATION IS THE ONE WE SEE MORE
OFTEN...WHERE A BAND OF SHOWERS AND STORMS CROSSES AHEAD OF THE
FRONT...AND THINGS CLEAR OUT BEHIND THE BOUNDARY.
REGIONAL RADARS SHOW A LARGE SWATH OF RAINFALL TO THE NORTH OF
THE I-4 CORRIDOR...OVER THE NATURE COAST ZONES THIS MORNING...WITH
MORE SCT VARIETY SHOWERS FURTHER SOUTH MOVING ASHORE FROM THE
GULF. SO FAR THE PAST FEW HOURS HAS SEEN LIMITED SOUTHWARD
MOVEMENT OF THIS MAIN RAIN SHIELD. HOWEVER...AS TIME PROGRESSES
TODAY...THE APPROACHING SHORTWAVE ENERGY ACROSS THE GULF COMBINED
WITH A FAVORABLE POSITION UNDER A COUPLED JET STRUCTURE WILL LEAD
TO MORE NUMEROUS SHOWERS EXPANDING SOUTHWARD INTO THE CENTRAL AND
SOUTHERN PORTIONS OF THE FORECAST AREA. WHILE THE I-4 CORRIDOR IS
EXPECTED TO BECOME RATHER WET FOR THE SECOND HALF OF THE DAY...THE
MORE STEADY SHOWERS ACTIVITY MAY HOLD OFF UNTIL THIS EVENING DOWN
TOWARD THE FORT MYERS AREA. THIS IS NOT TO SAY THERE WILL BE NO
RAIN SOUTH OF THE TAMPA BAY AREA...BUT IT SHOULD BE MORE SPORADIC
AND LIGHT FOR AT LEAST THE NEXT SEVERAL HOURS.
THE OVERALL SYNOPTIC FORCING IS ACTUALLY RATHER ROBUST OVER THE
PENINSULA LATER TODAY. DEEP LAYER Q-VECTOR CONVERGENCE IS
IMPRESSIVE...AND THIS WORKING IN TANDEM WITH THE JET STREAK
DIVERGENCE/DIFFLUENCE ALOFT SHOULD KEEP THE WEATHER UNSETTLED
THROUGH THE DAYLIGHT HOURS.
TEMPERATURES WILL BE COOL TODAY...ESPECIALLY WHEN COMPARED TO HOW
WARM DECEMBER WAS. NORTHERLY FLOW BEHIND THE COLD FRONT IS
DELIVERING A STEADY SUPPLY OF DRIER AIR NEAR THE SURFACE.
RAINFALL DESCENDING INTO THIS DRIER AIR WILL UNDERGO SOME
EVAPORATION. METEOROLOGISTS CALL THIS PROCESS THE "WET BULB EFFECT".
THE MAIN INFLUENCE OF THE "WET BULB EFFECT" IS TO COOL THE AIR
VIA EVAPORATION DOWN TOWARD THE DEWPOINT. WITH THE AIR HOLDING
MORE AND MORE MOISTURE AS RAIN EVAPORATES. THE DEWPOINT RISES AS
THE TEMPERATURE DROPS. WHEN THE TWO FINALLY MEET...THE AIR IS
SATURATED...THE EVAPORATION PROCESS ENDS...AND TEMPERATURES HOLD
STEADY.
RAIN WILL TAPER OFF TO THE NORTH OF THE I-4 CORRIDOR LATER
TODAY...AND THEN SLOWLY TAPER OFF FOR THE SOUTHERN HALF OF THE
FORECAST AREA OVERNIGHT. EXCELLENT AGREEMENT AMONG THE GUIDANCE
MEMBERS THAT THE FORCING AHEAD OF THE SHORTWAVE WILL EXIT TO OUR
EAST BY MONDAY MORNING. A REINFORCING SHOT OF COOL AND DRY AIR
WILL BE WORKING SOUTH ACROSS THE PENINSULA IN THE WAKE OF THIS
SYSTEM. BY SUNRISE ALL RAIN/SHOWERS SHOULD HAVE EXITED...EVEN THE
FORT MYERS AREA. FORECASTING A RATHER CHILLY NIGHT TONIGHT...WITH
LOW TEMPS BY SUNRISE MONDAY MORNING RANGING FROM THE UPPER 30S
AROUND CHIEFLAND...TO THE 40S ACROSS THE I-4 CORRIDOR...TO THE
LOWER/MIDDLE 50S DOWN BY CHARLOTTE AND LEE COUNTIES.
DEEP MOISTURE CONTINUES TO BE SCOURED OUT DURING THE DAY ON
MONDAY...AND SHOULD SEE A FAIR AMOUNT OF SUNSHINE AND TEMPERATURES
CLIMBING INTO THE 60S. WILL HAVE TO KEEP ANY EYE ON THE POTENTIAL
FOR SOME STATOCU MIGRATING OFF THE GULF IN THE NW FLOW MONDAY
MORNING...HOWEVER DOES APPEAR THAT THE LOW COLUMN TEMPS WILL BE
JUST A BIT TOO WARM TO RESULT IN WIDESPREAD LOW CLOUD
DEVELOPMENT...AND CERTAINLY TOO WARM TO SUPPORT ANY INSTABILITY
SPRINKLES MOVING ASHORE.
MORE FAIR WEATHER WITH SEASONABLY COOL TEMPERATURES FOR THE DAY ON
TUESDAY. BY WEDNESDAY...CLOUDS ARE ON THE INCREASE AHEAD OF THE
NEXT SOUTHERN STREAM IMPULSE TO APPROACH THE REGION.
HOWEVER...TEMPERATURES WILL ALSO BE ON THE INCREASE...WITH MANY
LOCATIONS ONCE AGAIN REACHING THE LOWER 70S.
&&
.AVIATION...
BAND OF RAINFALL SLOWLY PIVOTS SOUTHWARD THROUGH THE DAY...REACHING
KTPA/KPIE/KLAL/KSRQ LATE MORNING. A FEW SHOWERS ARE LIKELY EVEN
DOWN TOWARD KFMY/KRSW...BUT STEADIER SHOWER ACTIVITY LOOKS TO HOLD
OFF UNTIL THE EVENING. CONDITIONS WILL LIKELY BOUNCE AROUND
BETWEEN MVFR/VFR WITHIN THE RAIN SHIELD...BUT NOT SIGNIFICANT
RESTRICTIONS ARE ANTICIPATED. THE LAST OF THE RAINFALL SHOULD EXIT
SOUTH OF KFMY/KRSW BEFORE SUNRISE MONDAY. AN EXTENDED PERIOD OF
VFR CONDITIONS ARE THEN LIKELY FOR MONDAY AND TUESDAY.
&&
.MARINE...
ELEVATED WINDS AND SEAS WILL BE IN PLACE THROUGH TUESDAY NIGHT IN
THE WAKE OF A DEPARTING COLD FRONT. AN EXTENDED PERIOD OF
CAUTIONARY LEVEL CONDITIONS IS EXPECTED...WITH PERIODS OF
ADVISORY LEVEL WINDS. A SMALL CRAFT ADVISORY WILL LIKELY BE
REQUIRED FOR MONDAY NIGHT INTO TUESDAY. THE GRADIENT DOES LOOK TO
BRIEFLY RELAX DURING THE SECOND HALF OF THE WEEK...BEFORE THE NEXT
FRONT APPROACHES THE EASTERN GULF EARLY NEXT WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 62 49 66 47 / 90 70 0 0
FMY 71 55 69 49 / 80 90 10 0
GIF 61 45 63 46 / 90 80 0 10
SRQ 66 50 67 48 / 90 80 0 0
BKV 59 43 65 41 / 100 60 0 0
SPG 63 53 64 51 / 90 70 0 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION/MARINE...MROCZKA
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
843 PM CST MON JAN 4 2016
.UPDATE...
ISSUED AT 835 PM CST MON JAN 4 2016
Quiet weather is expected across central and southeast Illinois
overnight as a ridge of high pressure crosses the area. The main
weather feature of note is a plume of clouds streaming southwest
across parts of central Illinois from Lake Michigan. The other low
clouds that had been across the area faded with the loss of
diurnal heating. 00Z ILX and forecast soundings indicate a strong
capping inversion around 850 mb, which is about the height of the
lake clouds. The flow beneath this inversion is progged to turn
easterly within the next hour or two, and southerly by morning.
These shifting winds should help to remove these clouds from the
local area within the next few hours. The mostly clear skies and
light winds expected over the area for the rest of the night will
provide good radiational cooling conditions. This will allow
temperatures to fall a few degrees cooler than the past couple
nights, but overnight lows are still expected to be above normal
for early January.
Going forecast is in good shape overall. Updated sky grids to
better depict the lake clouds and their expected disposition.
Otherwise, only made a few hourly grid tweaks for the latest and
expected overnight trends.
&&
.SHORT TERM...(Tonight)
ISSUED AT 240 PM CST MON JAN 4 2016
Earlier hole in the stratocumulus has filled in across much of the
forecast area this afternoon, due to diurnal development and
additional clouds advecting in from Lake Michigan. Latest NAM 925 mb
humidity guidance suggesting the mostly cloudy trend to persist
through about 9 pm before clearing out, while the HRRR scatters the
clouds out closer to 6 pm. With the diurnal nature of most of the
clouds, leaned more toward the faster solution. As ridge axis pushes
east across the state, winds will trend toward the southeast after
midnight. Most locations should fall into the lower 20s overnight,
but some teens likely across the I-74 corridor.
.LONG TERM...(Tuesday through Monday)
ISSUED AT 240 PM CST MON JAN 4 2016
Quiet weather pattern to hold across the area through Wednesday
evening as upper level heights build over the Midwest allowing
warmer air to filter back into the region. Temperatures will
moderate a few degrees on Tuesday with the stronger return flow
setting up Tuesday night into Wednesday. This should push temps
Wednesday afternoon to around 40 degrees with the above normal
temperatures holding into Saturday. The storm system that is slated
to push out of the Southern Plains later Wednesday will begin to
spread precip into our area by Thursday morning. If the precip does
arrive before dawn Thursday, most of the forecast models suggest
more of a rain or freezing rain threat across our far northern
areas. For now, will keep it rain or snow and refine any precip
type issues as we draw closer to the event. The better rain
chances will move in late Thursday, Thursday night into Friday as
the main area of forcing/lift from the southern stream wave
pushes across our area, with rainfall amounts still looking to be
around one half inch.
As the storm system shifts to our northeast on Saturday, colder air
poised to our northwest will shift southeast into the region with
steady or slowly falling temperatures for the afternoon. We will
still have low chance POPs going during the day with a transition
from rain, to a rain snow mixture as the colder air filters in
during the afternoon as gusty northwest winds build in. Much colder
air will shift into the area Saturday night and Sunday accompanied
by gusty northwest winds. Most models suggest 850 temps of around
-20C by late Saturday night or Sunday as the center of the cold
air mass slides southeast into our area. This should result in
morning lows of 10 to 20 degrees by Monday morning with daytime
highs struggling mostly through the 20s Monday afternoon with the
below normal temperatures expected to hold through most of next
week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
ISSUED AT 549 PM CST MON JAN 4 2016
Mainly quiet/VFR aviation weather conditions expected across the
central Illinois terminals through the 00Z TAF valid time. High
pressure will build across the area tonight, accompanied by
light/variable winds. The high will drift off to the east by
Tuesday, with winds increasing above 10 kts out of the south on
the back side of the high. Some low clouds, mainly low-end VFR,
will impact the terminals for the next several hours, largely
streaming in off Lake Michigan. Then, high clouds will begin to
stream into the area Tuesday ahead of an approaching storm system.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...BAK
SHORT TERM...Geelhart
LONG TERM...Smith
AVIATION...BAK
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
553 PM CST MON JAN 4 2016
.SHORT TERM...(Tonight)
ISSUED AT 240 PM CST MON JAN 4 2016
Earlier hole in the stratocumulus has filled in across much of the
forecast area this afternoon, due to diurnal development and
additional clouds advecting in from Lake Michigan. Latest NAM 925 mb
humidity guidance suggesting the mostly cloudy trend to persist
through about 9 pm before clearing out, while the HRRR scatters the
clouds out closer to 6 pm. With the diurnal nature of most of the
clouds, leaned more toward the faster solution. As ridge axis pushes
east across the state, winds will trend toward the southeast after
midnight. Most locations should fall into the lower 20s overnight,
but some teens likely across the I-74 corridor.
.LONG TERM...(Tuesday through Monday)
ISSUED AT 240 PM CST MON JAN 4 2016
Quiet weather pattern to hold across the area through Wednesday
evening as upper level heights build over the Midwest allowing
warmer air to filter back into the region. Temperatures will
moderate a few degrees on Tuesday with the stronger return flow
setting up Tuesday night into Wednesday. This should push temps
Wednesday afternoon to around 40 degrees with the above normal
temperatures holding into Saturday. The storm system that is slated
to push out of the Southern Plains later Wednesday will begin to
spread precip into our area by Thursday morning. If the precip does
arrive before dawn Thursday, most of the forecast models suggest
more of a rain or freezing rain threat across our far northern
areas. For now, will keep it rain or snow and refine any precip
type issues as we draw closer to the event. The better rain
chances will move in late Thursday, Thursday night into Friday as
the main area of forcing/lift from the southern stream wave
pushes across our area, with rainfall amounts still looking to be
around one half inch.
As the storm system shifts to our northeast on Saturday, colder air
poised to our northwest will shift southeast into the region with
steady or slowly falling temperatures for the afternoon. We will
still have low chance POPs going during the day with a transition
from rain, to a rain snow mixture as the colder air filters in
during the afternoon as gusty northwest winds build in. Much colder
air will shift into the area Saturday night and Sunday accompanied
by gusty northwest winds. Most models suggest 850 temps of around
-20C by late Saturday night or Sunday as the center of the cold
air mass slides southeast into our area. This should result in
morning lows of 10 to 20 degrees by Monday morning with daytime
highs struggling mostly through the 20s Monday afternoon with the
below normal temperatures expected to hold through most of next
week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
ISSUED AT 549 PM CST MON JAN 4 2016
Mainly quiet/VFR aviation weather conditions expected across the
central Illinois terminals through the 00Z TAF valid time. High
pressure will build across the area tonight, accompanied by
light/variable winds. The high will drift off to the east by
Tuesday, with winds increasing above 10 kts out of the south on
the back side of the high. Some low clouds, mainly low-end VFR,
will impact the terminals for the next several hours, largely
streaming in off Lake Michigan. Then, high clouds will begin to
stream into the area Tuesday ahead of an approaching storm system.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...Smith
AVIATION...BAK
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1143 AM CST SUN JAN 3 2016
.SHORT TERM /TODAY/...
ISSUED AT 332 AM CST SUN JAN 3 2016
MAIN CONCERNS FOR TODAY WILL FOCUS ON CLOUDS/STRATUS DECK ADVANCING
INTO THE STATE AND IMPACT ON TEMPERATURES. CURRENTLY...FRONT HAS
PASSED THROUGH THE STATE WITH COLD ADVECTION INCREASING. BROAD
STRATUS FIELD ASSOCIATED WITH THE COLD ADVECTION HAS PUSHED RAPIDLY
SOUTHEAST THROUGH MINNESOTA OVERNIGHT AND INTO NORTHERN IOWA. BOTH
RAP AND HRRR CONTINUE TO ADVECT THIS QUICKLY SOUTH THIS
MORNING...EXPANDING ACROSS THE ENTIRE FORECAST AREA BY MID TO LATE
MORNING. NOT ALL MODELS ARE AS ROBUST AS THE HRRR AND RAP WITH THE
CLOUD COVER BUT GIVEN THE COLD ADVECTION AND CLIMATOLOGICALLY
FAVORABLE TIME OF YEAR...ANTICIPATE THE CLOUDS TO MOVE IN AND LINGER
THROUGH THE REST OF THE DAY. TEMPERATURES WILL NOT RISE MUCH TODAY
AS COLD AIR ARRIVES FROM THE NORTH ALONG WITH THE CLOUDS LIMITING
SOLAR INSOLATION. THE WINDS WILL REMAIN SOMEWHAT BRISK FROM THE
NORTHWEST THROUGH THE DAY AS WIND CHILLS HOLD IN THE SINGLE DIGITS
TO MID TEENS BY AFTERNOON.
.LONG TERM /TONIGHT THROUGH SATURDAY/...
ISSUED AT 332 AM CST SUN JAN 3 2016
THE FIRST CHALLENGE IN THIS LONG TERM FORECAST ISSUANCE WILL BE
HOW TO DEAL WITH THE STRATUS THAT WILL MAKE STEADY PROGRESS SOUTH
FROM TODAY. WE WILL REMAIN IN COLD ADVECTION TONIGHT AND I JUST DO
NOT SEE THE STRATUS GOING AWAY AT THIS POINT. FORECAST SOUNDINGS
ALL SHOW SOME LOW LEVEL MOISTURE HANGING IN HOWEVER THEY ALSO
SHOW...IN VARYING DEGREES...QUITE A BIT OF DRY AIR ALOFT SO I DO
GRADUALLY DIMINISH BUT DO NOT GET RID OF...THE STRATUS. BUT THIS
MAYBE TOO AGGRESSIVE. STRATUS TENDS TO HANG TOUGH THIS TIME OF
YEAR. OTHERWISE NOT MUCH CHANGE TO THE FORECAST THROUGH TUESDAY AS
WE REMAIN IN A NORTHERLY FLOW AND SEASONABLY COLD. I DID WARM
TEMPS A BIT MORE ON TUESDAY. THE UPPER RIDGING AND SURFACE HIGH
PRESSURE SHIFT EAST A BIT FASTER WHICH PUTS IOWA IN RETURN FLOW
FOR TUESDAY SO I NUDGED HIGHS WARMER ACROSS THE SOUTH AND
ESPECIALLY SOUTHWEST. AT THIS POINT I DIDN`T GET TOO CRAZY...JUST
NUDGING HIGHS A COUPLE DEGREES BUT THE SOUTH COULD BE SLIGHTLY
WARMER THAN THAT YET.
CHANGES WERE MADE FROM WEDNESDAY AND BEYOND...MAINLY BRINGING POPS
IN FOR WEDNESDAY AND NUDGING THEM HIGHER IN LATER PERIODS. THE
FIRST IN A SERIES OF SHORTWAVES MOVES ACROSS THE REGION DURING THE
DAY WEDNESDAY AND NOW FORCING WHICH DID NOT EXIST YESTERDAY IS
PRESENT DURING THE AFTERNOON AND WHILE IT IS WEAK...IT SHOULD BE
ENOUGH TO PRODUCE SOME PRECIP AS FORECAST SOUNDINGS DEFINITELY DO
SATURATE TO BY AFTERNOON. PTYPE WILL BE A HEADACHE GOING FORWARD
WITH NORTHERN AREAS SEEING MORE POTENTIAL FOR SNOW THAN THE SOUTH.
WEDNESDAY DOES LOOK COLD ENOUGH MOST LOCATIONS FOR A MORE WIDESPREAD
SNOW ALTHOUGH MORE OF A MIX COULD OCCUR ACROSS THE FAR SOUTH LATER
IN THE AFTERNOON.
DURING THE THURSDAY/FRIDAY PERIOD WHEN THE MAIN SYSTEM LIFTS
NORTHEAST AND THE BEST FORCING IS ACROSS US SOUNDINGS INDICATE THAT
PTYPE WILL BE MUCH MORE CHALLENGING WITH WARM ADVECTION ALOFT. TEMPS
ACROSS SOUTHERN IOWA WILL BE +3 OR SO ALOFT SO MIXED PRECIP...MAYBE
EVEN A PERIOD OR TWO OF FREEZING RAIN IS LIKELY. EVEN AS FAR NORTH
AS MASON CITY TEMPS ALOFT HOVER AROUND 0 TO +1 AND WHILE THIS
PROBABLY WON`T BE ENOUGH TO KICK PRECIP OVER TO SOMETHING OTHER THAN
SNOW IF WE GET A LITTLE WARMER THAN MODELS SUGGEST THE POSSIBILITY
WILL BE THERE.
BY LATE FRIDAY INTO SATURDAY THE SYSTEM LIFTS FAR ENOUGH TO THE
NORTHEAST TO ALLOW COLDER AIR TO MOVE INTO THE STATE AND ANY
REMAINING PRECIP WILL BE SNOW BY THIS PERIOD ALTHOUGH MODELS STILL
VARY AS TO THE SPEED AT WHICH THE SYSTEM DEPARTS. IF THE EURO IS
CORRECT THEN PRECIP SHOULD BE DONE IN THE MORNING. THE GFS HANGS ON
TO SNOW THROUGH MUCH OF THE DAY AND OVER A BROADER AREA AS WELL.
AFTER THIS SYSTEM PASSES WE WILL BE DEALING WITH SIGNIFICANTLY
COLDER AIR OVER THE REGION SO WE MAY BE IN FOR SOME OF THE COLDEST
AIR YET THIS WINTER.
&&
.AVIATION...03/18Z
ISSUED AT 1139 AM CST SUN JAN 3 2016
WIDESPREAD STRATUS DECK OVER IOWA THIS AFTERNOON AND WILL LIKELY
PERSIST THROUGH MUCH OF THE TAF PERIOD. IFR CONDITIONS ARE
CURRENTLY LOCATED ON THE WESTERN EDGE OF THE STRATUS WITH MVFR
MOVING INTO THE TAF SITES. EXPECT MAINLY MVFR CONDITIONS THROUGH
THE PERIOD THOUGH POSSIBLE CIGS RISE ABOVE 2 KFT AT TIMES. THAT
SAID...VISIBLE SATELLITE SHOWS HOW THIN THE STRATUS IS SO SOME
BREAKS MAY DEVELOP. A FEW SMALL BREAKS ARE APPARENT OVER SOUTHEAST
MN NOW.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COGIL
LONG TERM...FAB
AVIATION...DONAVON
AREA FORECAST DISCUSSION
NWS DES MOINES IA
527 AM CST SUN JAN 3 2016
.SHORT TERM /TODAY/...
ISSUED AT 332 AM CST SUN JAN 3 2016
MAIN CONCERNS FOR TODAY WILL FOCUS ON CLOUDS/STRATUS DECK ADVANCING
INTO THE STATE AND IMPACT ON TEMPERATURES. CURRENTLY...FRONT HAS
PASSED THROUGH THE STATE WITH COLD ADVECTION INCREASING. BROAD
STRATUS FIELD ASSOCIATED WITH THE COLD ADVECTION HAS PUSHED RAPIDLY
SOUTHEAST THROUGH MINNESOTA OVERNIGHT AND INTO NORTHERN IOWA. BOTH
RAP AND HRRR CONTINUE TO ADVECT THIS QUICKLY SOUTH THIS
MORNING...EXPANDING ACROSS THE ENTIRE FORECAST AREA BY MID TO LATE
MORNING. NOT ALL MODELS ARE AS ROBUST AS THE HRRR AND RAP WITH THE
CLOUD COVER BUT GIVEN THE COLD ADVECTION AND CLIMATOLOGICALLY
FAVORABLE TIME OF YEAR...ANTICIPATE THE CLOUDS TO MOVE IN AND LINGER
THROUGH THE REST OF THE DAY. TEMPERATURES WILL NOT RISE MUCH TODAY
AS COLD AIR ARRIVES FROM THE NORTH ALONG WITH THE CLOUDS LIMITING
SOLAR INSOLATION. THE WINDS WILL REMAIN SOMEWHAT BRISK FROM THE
NORTHWEST THROUGH THE DAY AS WIND CHILLS HOLD IN THE SINGLE DIGITS
TO MID TEENS BY AFTERNOON.
.LONG TERM /TONIGHT THROUGH SATURDAY/...
ISSUED AT 332 AM CST SUN JAN 3 2016
THE FIRST CHALLENGE IN THIS LONG TERM FORECAST ISSUANCE WILL BE
HOW TO DEAL WITH THE STRATUS THAT WILL MAKE STEADY PROGRESS SOUTH
FROM TODAY. WE WILL REMAIN IN COLD ADVECTION TONIGHT AND I JUST DO
NOT SEE THE STRATUS GOING AWAY AT THIS POINT. FORECAST SOUNDINGS
ALL SHOW SOME LOW LEVEL MOISTURE HANGING IN HOWEVER THEY ALSO
SHOW...IN VARYING DEGREES...QUITE A BIT OF DRY AIR ALOFT SO I DO
GRADUALLY DIMINISH BUT DO NOT GET RID OF...THE STRATUS. BUT THIS
MAYBE TOO AGGRESSIVE. STRATUS TENDS TO HANG TOUGH THIS TIME OF
YEAR. OTHERWISE NOT MUCH CHANGE TO THE FORECAST THROUGH TUESDAY AS
WE REMAIN IN A NORTHERLY FLOW AND SEASONABLY COLD. I DID WARM
TEMPS A BIT MORE ON TUESDAY. THE UPPER RIDGING AND SURFACE HIGH
PRESSURE SHIFT EAST A BIT FASTER WHICH PUTS IOWA IN RETURN FLOW
FOR TUESDAY SO I NUDGED HIGHS WARMER ACROSS THE SOUTH AND
ESPECIALLY SOUTHWEST. AT THIS POINT I DIDN`T GET TOO CRAZY...JUST
NUDGING HIGHS A COUPLE DEGREES BUT THE SOUTH COULD BE SLIGHTLY
WARMER THAN THAT YET.
CHANGES WERE MADE FROM WEDNESDAY AND BEYOND...MAINLY BRINGING POPS
IN FOR WEDNESDAY AND NUDGING THEM HIGHER IN LATER PERIODS. THE
FIRST IN A SERIES OF SHORTWAVES MOVES ACROSS THE REGION DURING THE
DAY WEDNESDAY AND NOW FORCING WHICH DID NOT EXIST YESTERDAY IS
PRESENT DURING THE AFTERNOON AND WHILE IT IS WEAK...IT SHOULD BE
ENOUGH TO PRODUCE SOME PRECIP AS FORECAST SOUNDINGS DEFINITELY DO
SATURATE TO BY AFTERNOON. PTYPE WILL BE A HEADACHE GOING FORWARD
WITH NORTHERN AREAS SEEING MORE POTENTIAL FOR SNOW THAN THE SOUTH.
WEDNESDAY DOES LOOK COLD ENOUGH MOST LOCATIONS FOR A MORE WIDESPREAD
SNOW ALTHOUGH MORE OF A MIX COULD OCCUR ACROSS THE FAR SOUTH LATER
IN THE AFTERNOON.
DURING THE THURSDAY/FRIDAY PERIOD WHEN THE MAIN SYSTEM LIFTS
NORTHEAST AND THE BEST FORCING IS ACROSS US SOUNDINGS INDICATE THAT
PTYPE WILL BE MUCH MORE CHALLENGING WITH WARM ADVECTION ALOFT. TEMPS
ACROSS SOUTHERN IOWA WILL BE +3 OR SO ALOFT SO MIXED PRECIP...MAYBE
EVEN A PERIOD OR TWO OF FREEZING RAIN IS LIKELY. EVEN AS FAR NORTH
AS MASON CITY TEMPS ALOFT HOVER AROUND 0 TO +1 AND WHILE THIS
PROBABLY WON`T BE ENOUGH TO KICK PRECIP OVER TO SOMETHING OTHER THAN
SNOW IF WE GET A LITTLE WARMER THAN MODELS SUGGEST THE POSSIBILITY
WILL BE THERE.
BY LATE FRIDAY INTO SATURDAY THE SYSTEM LIFTS FAR ENOUGH TO THE
NORTHEAST TO ALLOW COLDER AIR TO MOVE INTO THE STATE AND ANY
REMAINING PRECIP WILL BE SNOW BY THIS PERIOD ALTHOUGH MODELS STILL
VARY AS TO THE SPEED AT WHICH THE SYSTEM DEPARTS. IF THE EURO IS
CORRECT THEN PRECIP SHOULD BE DONE IN THE MORNING. THE GFS HANGS ON
TO SNOW THROUGH MUCH OF THE DAY AND OVER A BROADER AREA AS WELL.
AFTER THIS SYSTEM PASSES WE WILL BE DEALING WITH SIGNIFICANTLY
COLDER AIR OVER THE REGION SO WE MAY BE IN FOR SOME OF THE COLDEST
AIR YET THIS WINTER.
&&
.AVIATION...03/12Z
ISSUED AT 522 AM CST SUN JAN 3 2016
STRATUS WILL OVERSPREAD THE STATE BY 15Z WITH MVFR TO IFR CEILINGS
TODAY INTO TONIGHT. SOME DIFFERENCES NOTED IN MODELS IN REGARDS TO
DISSIPATION OVERNIGHT BUT GIVEN TIME OF YEAR AND CLIMATOLOGICALLY
FAVORABLE TO KEEP CLOUDS...HAVE GENERALLY KEPT THE CEILINGS
THROUGH THE END OF THE FORECAST PERIOD. SURFACE WINDS WILL REMAIN
FROM THE NORTHWEST THROUGH TONIGHT. VISIBILITIES MOSTLY
UNRESTRICTED.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...COGIL
LONG TERM...FAB
AVIATION...COGIL
AREA FORECAST DISCUSSION
NWS DES MOINES IA
335 AM CST SUN JAN 3 2016
.SHORT TERM /TODAY/...
ISSUED AT 332 AM CST SUN JAN 3 2016
MAIN CONCERNS FOR TODAY WILL FOCUS ON CLOUDS/STRATUS DECK ADVANCING
INTO THE STATE AND IMPACT ON TEMPERATURES. CURRENTLY...FRONT HAS
PASSED THROUGH THE STATE WITH COLD ADVECTION INCREASING. BROAD
STRATUS FIELD ASSOCIATED WITH THE COLD ADVECTION HAS PUSHED RAPIDLY
SOUTHEAST THROUGH MINNESOTA OVERNIGHT AND INTO NORTHERN IOWA. BOTH
RAP AND HRRR CONTINUE TO ADVECT THIS QUICKLY SOUTH THIS
MORNING...EXPANDING ACROSS THE ENTIRE FORECAST AREA BY MID TO LATE
MORNING. NOT ALL MODELS ARE AS ROBUST AS THE HRRR AND RAP WITH THE
CLOUD COVER BUT GIVEN THE COLD ADVECTION AND CLIMATOLOGICALLY
FAVORABLE TIME OF YEAR...ANTICIPATE THE CLOUDS TO MOVE IN AND LINGER
THROUGH THE REST OF THE DAY. TEMPERATURES WILL NOT RISE MUCH TODAY
AS COLD AIR ARRIVES FROM THE NORTH ALONG WITH THE CLOUDS LIMITING
SOLAR INSOLATION. THE WINDS WILL REMAIN SOMEWHAT BRISK FROM THE
NORTHWEST THROUGH THE DAY AS WIND CHILLS HOLD IN THE SINGLE DIGITS
TO MID TEENS BY AFTERNOON.
.LONG TERM /TONIGHT THROUGH SATURDAY/...
ISSUED AT 332 AM CST SUN JAN 3 2016
THE FIRST CHALLENGE IN THIS LONG TERM FORECAST ISSUANCE WILL BE
HOW TO DEAL WITH THE STRATUS THAT WILL MAKE STEADY PROGRESS SOUTH
FROM TODAY. WE WILL REMAIN IN COLD ADVECTION TONIGHT AND I JUST DO
NOT SEE THE STRATUS GOING AWAY AT THIS POINT. FORECAST SOUNDINGS
ALL SHOW SOME LOW LEVEL MOISTURE HANGING IN HOWEVER THEY ALSO
SHOW...IN VARYING DEGREES...QUITE A BIT OF DRY AIR ALOFT SO I DO
GRADUALLY DIMINISH BUT DO NOT GET RID OF...THE STRATUS. BUT THIS
MAYBE TOO AGGRESSIVE. STRATUS TENDS TO HANG TOUGH THIS TIME OF
YEAR. OTHERWISE NOT MUCH CHANGE TO THE FORECAST THROUGH TUESDAY AS
WE REMAIN IN A NORTHERLY FLOW AND SEASONABLY COLD. I DID WARM
TEMPS A BIT MORE ON TUESDAY. THE UPPER RIDGING AND SURFACE HIGH
PRESSURE SHIFT EAST A BIT FASTER WHICH PUTS IOWA IN RETURN FLOW
FOR TUESDAY SO I NUDGED HIGHS WARMER ACROSS THE SOUTH AND
ESPECIALLY SOUTHWEST. AT THIS POINT I DIDN`T GET TOO CRAZY...JUST
NUDGING HIGHS A COUPLE DEGREES BUT THE SOUTH COULD BE SLIGHTLY
WARMER THAN THAT YET.
CHANGES WERE MADE FROM WEDNESDAY AND BEYOND...MAINLY BRINGING POPS
IN FOR WEDNESDAY AND NUDGING THEM HIGHER IN LATER PERIODS. THE
FIRST IN A SERIES OF SHORTWAVES MOVES ACROSS THE REGION DURING THE
DAY WEDNESDAY AND NOW FORCING WHICH DID NOT EXIST YESTERDAY IS
PRESENT DURING THE AFTERNOON AND WHILE IT IS WEAK...IT SHOULD BE
ENOUGH TO PRODUCE SOME PRECIP AS FORECAST SOUNDINGS DEFINITELY DO
SATURATE TO BY AFTERNOON. PTYPE WILL BE A HEADACHE GOING FORWARD
WITH NORTHERN AREAS SEEING MORE POTENTIAL FOR SNOW THAN THE SOUTH.
WEDNESDAY DOES LOOK COLD ENOUGH MOST LOCATIONS FOR A MORE WIDESPREAD
SNOW ALTHOUGH MORE OF A MIX COULD OCCUR ACROSS THE FAR SOUTH LATER
IN THE AFTERNOON.
DURING THE THURSDAY/FRIDAY PERIOD WHEN THE MAIN SYSTEM LIFTS
NORTHEAST AND THE BEST FORCING IS ACROSS US SOUNDINGS INDICATE THAT
PTYPE WILL BE MUCH MORE CHALLENGING WITH WARM ADVECTION ALOFT. TEMPS
ACROSS SOUTHERN IOWA WILL BE +3 OR SO ALOFT SO MIXED PRECIP...MAYBE
EVEN A PERIOD OR TWO OF FREEZING RAIN IS LIKELY. EVEN AS FAR NORTH
AS MASON CITY TEMPS ALOFT HOVER AROUND 0 TO +1 AND WHILE THIS
PROBABLY WON`T BE ENOUGH TO KICK PRECIP OVER TO SOMETHING OTHER THAN
SNOW IF WE GET A LITTLE WARMER THAN MODELS SUGGEST THE POSSIBILITY
WILL BE THERE.
BY LATE FRIDAY INTO SATURDAY THE SYSTEM LIFTS FAR ENOUGH TO THE
NORTHEAST TO ALLOW COLDER AIR TO MOVE INTO THE STATE AND ANY
REMAINING PRECIP WILL BE SNOW BY THIS PERIOD ALTHOUGH MODELS STILL
VARY AS TO THE SPEED AT WHICH THE SYSTEM DEPARTS. IF THE EURO IS
CORRECT THEN PRECIP SHOULD BE DONE IN THE MORNING. THE GFS HANGS ON
TO SNOW THROUGH MUCH OF THE DAY AND OVER A BROADER AREA AS WELL.
AFTER THIS SYSTEM PASSES WE WILL BE DEALING WITH SIGNIFICANTLY
COLDER AIR OVER THE REGION SO WE MAY BE IN FOR SOME OF THE COLDEST
AIR YET THIS WINTER.
&&
.AVIATION...03/06Z
ISSUED AT 1143 PM CST SAT JAN 2 2016
PRIMARY CONCERN REMAINS STRATUS APPROACHING IA FROM MN...MOVING
AROUND 325/25KTS...AND CONFIDENCE HAS INCREASED IN AT LEAST SUB
2KFT MVFR CIGS FOR A PROLONGED PERIOD. MODELS STILL HAVE VARIED
SOLUTIONS BUT MORE AGGRESSIVE END BETTER FITS REALITY AND SUGGESTS
IT WILL AFFECT SITES THROUGH MUCH IF NOT THE ENTIRE PERIOD. A
PERIOD OF IFR CIGS IS ALSO LIKELY...BUT CONFIDENCE IN TIMING IS
NOT THERE YET SO STAYED WITH LOW END MVFR CIGS UNTIL TRENDS
BECOME MORE CLEAR.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...COGIL
LONG TERM...FAB
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1144 PM CST SAT JAN 2 2016
.SHORT TERM /TONIGHT/...
ISSUED AT 256 PM CST SAT JAN 2 2016
BREEZY WESTERLY WINDS WILL SWITCH FROM THE NORTHWEST OVERNIGHT AS A
BOUNDARY PASSES THROUGH THE STATE. A BROAD STRATUS DECK OVER
ONTARIO THROUGH MUCH OF MANITOBA WILL DROP SOUTH ALONG WITH THE
BOUNDARY OVERNIGHT. STILL SOME UNCERTAINTY ON HOW MUCH AREAL
COVERAGE THE STRATUS WILL HAVE ONCE IT ARRIVES. THE LATEST RAP 925
MB RH ANALYSIS MATCHES WELL WITH CURRENT PLACEMENT OF THE STRATUS.
USING THIS RH AND THE 925 MB WIND AS THE STEERING FLOW WIND...THE
STRATUS SHOULD BE NEAR HIGHWAY 20 BY 12Z FROM NORTH CENTRAL TO
NORTHEAST IOWA. THE CURRENT MOVEMENT IS SOUTH AT 38 KTS...WHICH
WOULD PLACE TIME OF ARRIVAL OVER NORTHERN IOWA AROUND 06Z. PRIMARY
IMPACT ON TIME OF ARRIVAL IS AVIATION CONCERNS BUT ALSO OVERNIGHT
LOW TEMPERATURES. HAVE KEPT THE NORTH A BIT WARMER BASED ON ARRIVAL
OF CLOUD COVER. NO FLURRIES ADDED AT THIS TIME WITH THE MOIST LAYER
TEMPERATURES WARMER THAN THE PREFERRED DENDRITIC GROWTH ZONE.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
ISSUED AT 256 PM CST SAT JAN 2 2016
CONTINUED QUIET WEATHER FOR THE NEXT SEVERAL DAYS...THOUGH WITH THE
COLD FRONT AND UPPER LEVEL TROUGH APPROACHING OUR AREA BY TOMORROW
MORNING...STRATUS SHIELD NOW OVER NORTHERN MINNESOTA WILL EVENTUALLY
BRING SIGNIFICANT CLOUD COVER TO THE REGION SUNDAY THROUGH EARLY
MONDAY. ONCE THE UPPER LEVEL RIDGE BEGINS TO PULL EAST...
ANTICYCLONIC ROTATION AND SUBSIDENCE WILL ACT TO CLEAR SKIES BY
MONDAY AFTERNOON MOST AREAS. TEMPERATURES WILL BE HELD DOWN A BIT
MORE OVER THE NORTHEAST HALF OF THE AREA ON SUNDAY...WHILE THE WEST
MAY SEE ENOUGH SUNSHINE FOR A FEW DEGREES WARMER TEMPERATURES. BY
LATE SUNDAY NIGHT CLOUDS WILL SLOWLY ERODE...WITH COLDER OVERNIGHT
LOWS IN THE WEST. BY MONDAY AFTERNOON THE RIDGE IS BEGINNING TO
BUILD EAST. EARLIER FORECASTS SUGGESTED THE TROUGH TO HOLD ON LONGER
OVER THE GREAT LAKES...BUT ALL MEDIUM RANGE MODELS HAVE COME AROUND
TO A SLIGHTLY MORE PROGRESSIVE SOLUTION. THE BEST MODEL EARLIER WAS
THE GFS...THOUGH IT INITIALLY HAD THE COLD AIR MOVING OUT TOO FAST
WHILE THE GEM/EURO WERE BOTH TOO SLOW. TEMPERATURES WILL ALREADY BE
WARMING UP LATE MONDAY EVENING ALOFT...SO MINS OVER THE WEST WILL BE
MILDER. ACROSS THE EAST...LIGHTER SFC WINDS WILL STILL ALLOW FOR
SOME LOCATIONS TO REACH THE SINGLE DIGITS TUESDAY MORNING.
THE MAIN WEATHER MAKER WILL CONTINUES TO BE THE MID TO LATE WEEK
SYSTEM PROGGED TO REACH THE CALIFORNIA COAST TUESDAY NIGHT. A WEAKER
LESS AMPLIFIED SHORT WAVE WILL TRACK INTO THE CENTRAL PLAINS ALREADY
ON WEDNESDAY. WITH LITTLE MOISTURE RETURN AND SOME LIFT DUE TO BOTH
THE WAVE AND WARM AIR ADVECTION...EXPECTING SOME VERY LIGHT
PRECIPITATION OR A MIX OF DRIZZLE/LIGHT SNOW TO OCCUR DURING THE
DAYTIME HOURS. GFS BUFR SOUNDINGS SUGGEST A RATHER SHALLOW LAYER
OF MOISTURE INITIALLY...WITH LITTLE ICE INTRODUCTION ON WEDNESDAY.
THE MORE DYNAMIC SYSTEM IS EXPECTED TO REACH THE REGION ON
THURSDAY INTO FRIDAY...BEGINNING AS A MIX OF PRECIPITATION
THURSDAY AND FRIDAY...CHANGING TO ALL SNOW BY FRIDAY NIGHT AND
LINGERING LIGHT SNOW ON SATURDAY. TEMPERATURES OVER THE SOUTHEAST
ARE EXPECTED TO WARM TO ABOVE THE FREEZING MARK INTO THE MID 30S
FOR WEDNESDAY/THURSDAY/FRIDAY...SO MUCH OF THE PRECIPITATION MAY
EITHER END UP AS A MIX OR PLAIN RAIN. OVERNIGHT AND EARLY MORNING
MAY SEE THE PRECIP SWITCH BACK OVER TO A FROZEN MIX. WITH GULF
MOISTURE MORE AVAILABLE BY WEEKS END...SOME ACCUMULATING SNOW
SHOULD OCCUR ON THE BACKSIDE OF THE SYSTEM AS IT DEPARTS FRIDAY
EVENING INTO SATURDAY. AT THIS TIME AMOUNTS ARE EXPECTED TO BE ON
THE LIGHT SIDE.
AS MENTIONED YESTERDAY COLD AIR REALLY DOES NOT REACH THE SYSTEM
FAST ENOUGH FOR STRONGER AMPLIFICATION PRIOR TO THE STORMS
DEPARTURE. AS WE GET CLOSER TO THE EVENT...MORE DETAILS WILL BE
AVAILABLE FOR PRECIPITATION TYPES THURSDAY INTO FRIDAY. ONCE THE
SYSTEM DEPARTS THE REGION LATE ON SATURDAY COLDER AIR WILL BEGIN
DRIVING SOUTH INTO THE NORTHERN PLAINS AND EVENTUALLY IOWA.
CURRENTLY...THE CLIMATE PREDICTION CENTERS 8/14 DAY OUTLOOK IS FOR
COLDER THAN NORMAL TEMPERATURES...AND JUDGING BY THE UPSTREAM
AIRMASS AND SOME CONSISTENCY OVER THE PAST TWO MEDIUM RANGE MODEL
RUNS OF THE EURO/GFS...THIS LOOKS LIKE A GOOD BET FOR NOW.
&&
.AVIATION...03/06Z
ISSUED AT 1143 PM CST SAT JAN 2 2016
PRIMARY CONCERN REMAINS STRATUS APPROACHING IA FROM MN...MOVING
AROUND 325/25KTS...AND CONFIDENCE HAS INCREASED IN AT LEAST SUB
2KFT MVFR CIGS FOR A PROLONGED PERIOD. MODELS STILL HAVE VARIED
SOLUTIONS BUT MORE AGGRESSIVE END BETTER FITS REALITY AND SUGGESTS
IT WILL AFFECT SITES THROUGH MUCH IF NOT THE ENTIRE PERIOD. A
PERIOD OF IFR CIGS IS ALSO LIKELY...BUT CONFIDENCE IN TIMING IS
NOT THERE YET SO STAYED WITH LOW END MVFR CIGS UNTIL TRENDS
BECOME MORE CLEAR.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...DONAVON
LONG TERM...REV
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
449 PM MST MON JAN 4 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 1245 PM MST MON JAN 4 2016
A RIDGE WILL REMAIN OVER THE PLAINS TONIGHT AND THEN SHIFT EAST
TUESDAY WITH SOUTHWEST FLOW ACROSS THE REGION. SURFACE HIGH PRESSURE
WILL REMAIN OVER THE PLAINS TONIGHT. HIGH PRESSURE WILL MOVE EAST
TUESDAY AS A SURFACE TROUGH MOVES INTO EASTERN COLORADO.
THE FORECAST WILL REMAIN DRY TONIGHT DUE TO SUBSIDENCE. A SHORTWAVE
WILL MOVE ACROSS THE FA TUESDAY BUT FORCING AND MOISTURE ARE BOTH
LACKING. POPS WILL BE NIL TONIGHT AND TUESDAY.
THE HRRR INDICATES THE POSSIBILITY OF SOME PATCHY FREEZING FOG EARLY
TUESDAY MORNING FOR A FEW HOURS NEAR NORTON AND GRAHAM COUNTIES.
CONFIDENCE IS RATHER LOW BUT CANNOT RULE IT OUT. PLAN TO INSERT SOME
PATCHY FREEZING FOG IN THAT AREA.
MIN TEMPERATURES TONIGHT SHOULD FALL BACK TO THE TEENS IN EASTERN
COLORADO WITH LOWER 20S ELSEWHERE. MAX TEMPERATURES TUESDAY SHOULD
REACH THE MID 40S.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 157 PM MST MON JAN 4 2016
THE UPPER SHORT WAVE TROUGH WILL CONTINUE TO LIFT OUT ACROSS THE
CENTRAL HIGH PLAINS REGION TUESDAY NIGHT AND WEDNESDAY MORNING
WITH THE SURFACE TROUGH PUSHING FAR ENOUGH EAST THAT PRECIPITATION
ASSOCIATED WITH THE OPEN WAVE WILL LIKELY REMAIN SOUTH AND EAST
OF THE FORECAST AREA. THERE WILL BE BRIEF SHORT WAVE RIDGING ALOFT
WEDNESDAY AND WEDNESDAY NIGHT WITH DRY CONDITIONS.
A SURFACE LOW REDEVELOPS OVER SOUTHEAST COLORADO AHEAD OF THE
NEXT TROUGH THAT MOVES ACROSS THE FORECAST AREA THURSDAY INTO
THURSDAY EVENING. THE SOUTHERLY FETCH OF GULF MOISTURE STREAMING
INTO THE PLAINS STATES TURNS IT`S FOCUS ON THE CENTRAL HIGH PLAINS
WITH A MORE SOUTHEASTERLY FLOW AS THE SURFACE LOW MOVES INTO THE
PANHANDLE REGION. MOISTURE INCREASES IN THE COLUMN THURSDAY...BUT
INITIALLY REMAINS DRYER BETWEEN 850-700MB...SO PRECIPITATION THAT
MOVES INTO THE AREA EARLY THURSDAY MORNING LOOKS LIKE IT MAY START
AS FREEZING DRIZZLE BEFORE SURFACE TEMPERATURES WARM DURING THE
DAY AND THE COLUMN APPROACHES SATURATION AROUND 18Z. THE SURFACE
LOW MOVES INTO SOUTHEAST KANSAS BY THURSDAY NIGHT WITH
TEMPERATURES FALLING AND QUICKLY CHANGING PRECIPITATION OVER TO
ALL SNOW. THE LOW MOVES INTO NORTHERN MISSOURI BY
FRIDAY...BRINGING THE LIGHT SNOW TO AN END FROM WEST TO EAST BY
FRIDAY NIGHT.
BEYOND FRIDAY...MODEL SOLUTIONS FALL OUT OF AGREEMENT. HOWEVER...BOTH
THE ECMWF AND GFS SHOW STRONG SURFACE COLD AIR ADVECTION AS THE
MAIN UPPER FLOW MOVES WELL SOUTH OVER NORTHERN MEXICO...SURFACE
HIGH PRESSURE MOVES INTO THE REGION SATURDAY AND CONTINUES INTO
THE SOUTHERN PLAINS ON SUNDAY. LOW TEMPERATURES IN THE SINGLE
DIGITS...AND POSSIBLY BELOW ZERO...MAY BE OBSERVED THROUGH THE
WEEKEND WITH HIGH TEMPERATURES ONLY REACHING INTO THE UPPER TEENS
TO MIDDLE 20S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 448 PM MST MON JAN 4 2016
VFR CONDITIONS FOR BOTH TAF SITES WITH BKN150-250. WINDS SSE
10-20KTS WITH GUSTS TO 30KTS(FOR KGLD) BEFORE 06Z TUESDAY AND
AFTER 14Z TUESDAY. LOW LEVEL WIND SHEAR 06Z-15Z 18040KTS(190 FOR
KGLD).
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...FS
LONG TERM...LOCKHART
AVIATION...JN
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
332 PM CST SUN JAN 3 2016
.SHORT TERM...(This Evening through Monday)
Issued at 329 PM CST SUN JAN 3 2016
Tonight and Monday
Mid level ridging over the central CONUS continues to increase this
afternoon as broad troughing occurs from the Midwest towards the
Great Lakes region. Low stratus on the eastern edge of the high
pressure over Iowa into northern Missouri has slowly sank southward
through the day today. As the sun sets, temps currently in the
mid and upper 30s will quickly cool, carrying the stratus westward.
Forecast soundings develop a low stratus layer between 00 and 06Z at
the 950 mb layer. Some uncertainty exists between guidance on
timing of the stratus moving into the area, given the poor handling
of todays temperatures and lack of cloud cover. Forecast sided
closer to the RAP and HRRR solutions which have seemed to handled
trends through the afternoon. This result will also result in warmer
lows tonight in the upper teens and lower 20s given the mostly
cloudy skies. Patchy fog is also of concern, especially over north
central Kansas where cool temps and slower onset of cloud cover
could result in dense fog. Coverage and confidence is not high
enough for a headline at this time.
Sfc ridge progresses slowly eastward into northern Missouri Monday
shifting winds to the east and southeast below 10 mph. If widespread
stratus forms overnight, it will be difficult to mix out especially
over far east central Kansas where mixing remains very weak within
the boundary layer. Clearing is likely for most of the area by late
afternoon as better dry advection and mixing from the southeast will
help temps reach the low and middle 30s.
.LONG TERM...(Monday Night through Sunday)
Issued at 329 PM CST SUN JAN 3 2016
An upper ridge over the Central CONUS Monday
evening will move east Tuesday as a series of shortwave troughs move
into the plains from the desert southwest. The first shortwave
appears to be weakening as it moves through the central plains
Tuesday night and early Wednesday. The second, stronger wave,
should move through Thursday night and Friday. The northern stream
finally gets into the action late in the forecast period as
shortwave energy moves into the northern rockies and plains late in
the period. The models are in general agreement concerning these
large-scale features.
For northeast Kansas, we should have a few rounds of precipitation
associated with the passage of the upper troughs. The initial wave
will have limited moisture to work with Tuesday night and Wednesday.
Only brief focused forcing is expected and deeper moisture around
12Z Wednesday morning. While there is ice in the sounding, light
snow looks favored. However, in the absence of deep moisture and
forcing, soundings suggest a chance of freezing drizzle. Will have a
mixture of light freezing drizzle/light snow Tuesday night and early
Wednesday with small pops. Once the shortwave energy passes, low-
levels should remain nearly saturated over eastern Kansas with
sustained southerly flow in that layer. With only marginal UVV, will
keep a small chances of drizzle/light rain Wednesday into Wednesday
night.
The second round of precipitation Thursday and Friday should be more
significant, but based on temperature profiles at the time, it
should be all liquid precipitation over northeast Kansas. As the
system pulls out Friday night, what is left of the precipitation may
change over to light snow. However, by that point, the precipitation
chances are diminishing quickly.
Dry for the rest of the forecast next weekend with seasonally cold
temperatures. True arctic air should remain out of the area until
after the forecast period, but it may arrive next week.
As for temperatures, small diurnal ranges look likely with the
cloudiness and precipitation expected. Close to normal for highs,
but above normal lows.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1126 AM CST SUN JAN 3 2016
Difficult aviation forecast with respect to the stratus and fog
potential commencing between 00Z and 06Z. Short term guidance
differs on if and when band of stratus currently over southern IA
will reach terminals. Sided closer to the HRRR and RAP models who
have had a better handle on current trends with MVFR developing
near 02Z as high pressure develops a stout sfc inversion. As the
near sfc saturates, a mix of IFR stratus and MVFR visibilities are
likely through 15Z. LIFR is more likely at KFOE while patches of
IFR fog is possible over KMHK where stratus coverage is more
uncertain. Will need to monitor as amendments are likely.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Bowen
LONG TERM...Johnson
AVIATION...Bowen
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
318 PM CST SUN JAN 3 2016
...Updated...
.SYNOPSIS...
ISSUED AT 236 PM CST SUN JAN 3 2016
Upper level ridging will develop over the high plains through
early Monday. Meanwhile, cool surface high pressure over the
central plains will slowly slide off to the east. A series of
upper level disturbances will move onshore into California and
then traverse the central and southern plains starting Tuesday. A
weak surface trough will persist in the lee of the Rockies Monday
through Wednesday. By this weekend, a deep upper level trough is
advertised to swing southward out of Canada into the northern
Rockies, with arctic surface high pressure progressing into the
northern plains.
&&
.SHORT TERM...(THIS EVENING THROUGH Monday)
ISSUED AT 236 PM CST SUN JAN 3 2016
Winds will be fairly light for most of tonight, but should become
southeasterly by morning due to the aforementioned lee trough
development. Temperatures should easily fall into the upper teens
to lower 20s. The NAM and RAP hint at fog development, but
current thinking is that any fog would be confined to the
Interstate 70 corridor in central Kansas. Despite the south-
southeast winds on Monday, highs will probably only top out in the
upper 30s to lower 40s due to the light upslope wind component. A
few high clouds may move into western Kansas in the afternoon.
.LONG TERM...(Monday NIGHT THROUGH Sunday)
ISSUED AT 236 PM CST SUN JAN 3 2016
Weak lee troughing and southerly flow will allow for
some moisture return and milder overnight lows by mid-week.
Seasonable high temperatures can be expected through much of next
week in the absence of strong downslope flow or arctic air. There
are slight chances for rain Wednesday night into Thursday night
as upper level disturbances arrive from the southwest in the
presence of increasing low to mid level moisture and isentropic
lift. It is unclear whether it will be cold enough by Thursday
night for a changeover to snow across central and west central
Kansas. Most of the precipitation, albeit fairly light, should be
over by Friday. Colder air will move into western Kansas by
Saturday and Sunday as the leading edge of an arctic airmass
passes western Kansas.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Monday AFTERNOON)
ISSUED AT 1150 AM CST SUN JAN 3 2016
Surface high pressure will be situated across the central plains
through the period, resulting in light winds at the terminals.
VFR conditions will generally persist. However, the NAM and RAP
develop fog in central Kansas between 06 and 12z as weak upslope
flow develops after a night of radiational cooling. The NAM seems
to be too aggressive with the fog all the way south to KDDC. We
opted to keep the fog at KHYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 18 40 23 40 / 0 0 0 0
GCK 17 41 22 40 / 0 0 0 0
EHA 20 43 25 43 / 0 0 0 0
LBL 20 42 23 40 / 0 0 0 0
HYS 15 37 21 41 / 0 0 0 0
P28 18 40 21 40 / 0 0 0 0
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SYNOPSIS...Finch
SHORT TERM...Finch
LONG TERM...Finch
AVIATION...Finch
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1141 AM CST SUN JAN 3 2016
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 343 AM CST SUN JAN 3 2016
Forecast getting much more complicated in the short term. Upper
trough swinging southeast through the Great Lakes bringing a cold
front through the area with pressure change observations suggesting
it was south of the local area at 08Z with only minor wind
differences around it. Low stratus deck lagging behind, just
entering northern Iowa at 07Z and back west into eastern South
Dakota on north winds.
Models giving various depictions of the cloud through tonight, with
their recent cold/wet bias in the boundary layer further
complicating matters. Using merely a timing tool brings the stratus
into northeast Kansas around 16Z though expect at least a bit of
mixing to eat into it in daytime heating. Will bring some increased
cloud into northern and eastern areas this afternoon similar to
latest HRRR. North winds bring cold air advection through the day
for highs several degrees colder than Saturday, though again have
lower confidence in specifics with model cold bias and stratus
questions. Center of surface high comes SSE into eastern Nebraska
tonight for a continued backing and weakening of low level winds.
This could further usher the stratus in, and if not the stratus, at
least a rather humid boundary layer with light winds. Have expanded
the fog mention a bit more south and east, but winds may stay up
enough to keep fog in at least east central Kansas.
.LONG TERM...(Monday through Saturday)
Issued at 343 AM CST SUN JAN 3 2016
Monday is likely to be the coolest day of the week. There is some
potential to start the day with stratus or fog, but this should
erode by mid day with ample sunshine thereafter. Also expect a
rather cool start to the day so while a good recovery is expected,
still only will top out in the lower to middle 30s. Monday night
through Tuesday will see southerly flow return to the region. Low
level moisture will also make a return by late Tuesday. This is
in response to short wave energy moving across the southwestern
CONUS with an increasing jet aloft. The initial short wave trough
to cross the area will do so on Tuesday night, with modest upward
vertical motion contributing to deeper saturation. Temperatures on
Tuesday night will be near and probably just a bit colder than
freezing. Model forecast soundings support light snow with a
change over to drizzle and/or freezing drizzle as the system
passes. Any snow is likely to be quite light while the potential
for freezing drizzle is potentially more impactful. The main issue
with freezing drizzle potential is if there will be any drizzle
prior to temperatures warming above freezing given a likelihood
for steady or rising temperatures around sunrise. For now, this
is a period to keep a close eye on in terms of having some small
potential for travel hazards before temperatures warm on
Wednesday.
A stronger short wave trough will quickly follow the initial trough,
and while there will be a period of drying aloft on Wednesday,
drizzle or light rain showers will probably remain in the area
during the day. Stronger lift and deeper saturation will overspread
the area Wednesday night and persist into Friday night as this
system pivots and interacts with another incoming strong vort max
during the period. This should result in a prolonged period of
scattered to widespread precipitation. The primary precip type is
likely to be rain and drizzle with some chance to mix with snow
again as the event winds down. Feel pretty confident in a mainly
rain forecast, but temperature profiles will not be particularly
warm and it is a fairly complex system evolution so will want to
keep a close eye on the storm track and temperature profiles as
areas just to the north over Nebraska could be looking at some
healthy snow accumulations.
Cooler air builds in for the weekend but our first real shot of cold
winter air is on track for next week as ensemble and analog guidance
paints a rather high likelihood for much cooler than normal
temperatures.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1126 AM CST SUN JAN 3 2016
Difficult aviation forecast with respect to the stratus and fog
potential commencing between 00Z and 06Z. Short term guidance
differs on if and when band of stratus currently over southern IA
will reach terminals. Sided closer to the HRRR and RAP models who
have had a better handle on current trends with MVFR developing
near 02Z as high pressure develops a stout sfc inversion. As the
near sfc saturates, a mix of IFR stratus and MVFR visibilities are
likely through 15Z. LIFR is more likely at KFOE while patches of
IFR fog is possible over KMHK where stratus coverage is more
uncertain. Will need to monitor as amendments are likely.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...65
LONG TERM...Barjenbruch
AVIATION...Bowen
AREA FORECAST DISCUSSION
NWS JACKSON KY
1243 PM EST SUN JAN 3 2016
.UPDATE...
ISSUED AT 1244 PM EST SUN JAN 3 2016
STRATUS DECK IS MAKING SOME HEADWAY SOUTH...BUT SOME OF THIS DECK
IS ERODING ON THE EDGES. RIGHT NOW WILL STICK WITH WHAT WE HAVE
GOING AT THIS POINT. OTHERWISE SUNNY SKIES AND TEMPS IN THE LOW TO
MID 40S ARE THE STORY THIS AFTERNOON...WITH A FEW HIGH CLOUDS
NEARER THE VA/TN BORDER. UPDATED TEMPS/DEWS/WINDS WITH LATEST OBS
AND TRENDS.
UPDATE ISSUED AT 1043 AM EST SUN JAN 3 2016
THE BIGGEST ISSUE IN THE NEAR TERM WILL BE WHEN DOES THE STRATUS
MAKE IT INTO THE REGION...RIGHT NOW KEEPING THE MORE ROBUST
CLOUDS IN THE FAR NORTH. THE HRRR SEEMS TO HAVE A DECENT HANDLE ON
THIS SO WENT IN THAT DIRECTION. OTHERWISE MOST SHOULD REMAIN
MOSTLY SUNNY THOUGH MUCH OF THE DAY WITH TEMPS IN THE LOW TO MID
40S. UPDATED TEMPS/DEWS/WINDS WITH LATEST OBS AND TRENDS.
UPDATE ISSUED AT 735 AM EST SUN JAN 3 2016
HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT OBSERVATIONS. THE
VALLEYS IN THE COUNTIES NEAR INTERSTATE 64 REMAINED A BIT MORE
MIXED THAN ANTICIPATED AHEAD OF THE APPROACHING BOUNDARY SO
TEMPERATURES THERE WERE RAISED A BIT FOR THE NEXT COUPLE OF HOURS.
OTHERWISE...NO CHANGES WERE NECESSARY AT THIS TIME.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 258 AM EST SUN JAN 3 2016
EARLY THIS MORNING...A CLOSED LOW AND UPPER LEVEL TROUGH WAS
CENTERED OVER EASTERN CANADA AND EXTENDED SOUTH INTO THE GREAT
LAKES AND EASTERN CONUS. WITHIN THIS TROUGH A COUPLE OF SHORTWAVE
TROUGHS WERE ROTATING INTO AND THROUGH THE GREAT LAKES REGION WITH
ANOTHER FURTHER NORTH. AT THE SFC...A RIDGE OF HIGH PRESSURE WAS
CENTERED FROM THE SOUTHERN PLAINS INTO THE SOUTHEAST WITH ANOTHER
SFC HIGH ACROSS THE NORTHERN ROCKIES TO NORTHERN PLAINS AND
CANADIAN PLAINS REGIONS. IN BETWEEN A SFC TROUGH OR WEAK COLD
FRONT WAS NEARING THE OH VALLEY WHILE A STRONGER COLD FRONT
EXTENDED ACROSS THE NORTHERN GREAT LAKES FROM A SFC LOW OVER
EASTERN ONTARIO AND WESTERN QUEBEC.
LATE TONIGHT AND INTO THE DAY ON SUNDAY...THE FIRST WEAKER COLD
FRONT/SFC TROUGH IS EXPECTED TO MOVE ACROSS EASTERN KY WHILE THE
NEXT BOUNDARY IS EXPECTED TO SAG INTO THE CENTRAL GREAT LAKES AS
THE SFC LOW MOVES INTO THE CANADIAN MARITIMES. A COUPLE OF
SHORTWAVE TROUGHS WILL MOVE FROM THE GREAT LAKES AND INTO THE
NORTHEASTERN CONUS DURING THIS TIME...WITH ANOTHER MOVING INTO THE
LOWER OH VALLEY AND YET ANOTHER ONE MOVING INTO THE NORTHERN AND
WESTERN GREAT LAKES. ACROSS THE LOCAL AREA...TEMPERATURES SHOULD
AVERAGE NEAR TO SLIGHTLY ABOVE NORMAL FOR EARLY JANUARY AS THE
LOW LEVEL AND UPPER LEVEL FLOW BEGIN TO MOVE FROM SOUTHWESTERLY TO
WEST TO MORE WESTERLY TO EVEN NORTHWESTERLY. 850 MB TEMPS
INITIALLY WILL BE A COUPLE OF DEGREES ABOVE 0C BUT AS A SHORTWAVE
TROUGH APPROACHES WILL SLIDE TO BELOW 0C BY LATE AFTERNOON TO
EARLY EVENING.
TONIGHT INTO THE DAY ON MONDAY...A SHORTWAVE WILL MOVE ACROSS THE
LOWER OH VALLEY AND INTO THE APPALACHIANS EARLY IN THE PERIOD AND
BRING SOME LOW LEVEL MOISTURE AND LEAD TO A FURTHER DROP IN 850
MB TEMPS FROM THE SINGLE DIGITS BELOW 0C TO THE -10C TO -12C
RANGE. ANOTHER SHORTWAVE WILL BRING THE COLDEST OF THE 850 MB AIR
ACROSS THE AREA ON TUESDAY WITH 850 MB TEMPS FALLING TO ABOUT THE
-11C TO -14C RANGE.
THE MAIN FORECAST CONCERN AND CHALLENGE DURING THE SHORT TERM
PERIOD WILL BE THE UPPER LEVEL DISTURBANCES AND COLD FRONT THAT
MOVE ACROSS THE AREA OR APPROACH AREA LATE TONIGHT AND THEN MOVE
ACROSS THE REGION ON MONDAY AND ASSOCIATED SNOW SHOWERS AND OR
SNOW SQUALLS. STEEPENING LAPSE RATES AND INCREASING LOW LEVEL
MOISTURE SHOULD LEAD TO SOME FLURRIES OR ISOLATED TO SCATTERED SNOW
SHOWERS BY LATE TONIGHT.
THEN ON MONDAY...THE SNOW SHOW SHOWERS WILL PROBABLY BRING THE FIRST
MEASURABLE SNOW OF THE SEASON TO SEVERAL LOCATIONS. CURRENT MODEL
GUIDANCE HAS THE SNOW SQUALL PARAMETER PEAKING IN THE 2 TO 3 RANGE
GENERALLY DOWN THE MIDDLE OF THE CWA FROM 14Z TO 20Z OR MID TO LATE
MONDAY MORNING INTO EARLY TO MID AFTERNOON ON MONDAY. THE NAM
HOLDS ONTO THESE HIGHER INSTABILITY NUMBERS A BIT LONGER AND
FURTHER NORTH AS LATE AS 21Z ON MONDAY WHILE THE GFS AND ECMWF
HAVE DRIER AIR MOVING IN AND SHUTTING OF THE SNOW SHOWERS...SO
SOME UNCERTAINTY REMAINS IN THE EXACT TIMING AND LOCATIONS OF
THESE.
THE NAM HAS A PEAK IN QPF GENERALLY EAST OF A SYM TO JKL TO
I35 LINE TO NEAR LNP...WHILE THE GFS AND ECMWF ALSO HAVE A MORE
SUBTLE MAX ACROSS THE CENTRAL OR EASTERN PART OF THE AREA. AT
THIS POINT...WE HAVE WENT WITH A FEW HUNDREDTHS OF QPF A LITTLE
CLOSER TO OPERATION MODELS THAN THE SUPERBLEND...WITH GENERALLY A
TENTH TO LESS THAN A HALF OF AN INCH OF TOTAL SNOW. SOME ISOLATED
HIGHER AMOUNTS CANNOT BE RULED OUT IF A LOCATION WERE TO RECEIVE
MULTIPLE SNOW SHOWERS OR SOME NORTH TO SOUTH ORIENTED BANDING WERE
TO SET UP. OVERALL...THE HIGHER AMOUNTS SHOULD OCCUR ON THE
RIDGETOPS WHICH WILL REMAIN A DEGREE OR TWO COLDER THROUGHOUT THE
DAY ON MONDAY IN THE COLD ADVECTION PATTERN. THIS EVENT WILL
CONTINUE TO BE HIGHLIGHTED IN THE HWO AND IN THE WEATHER STORY...WITH
REDUCTIONS IN VISIBILITY AND SOME LIGHT QUICK ACCUMULATIONS
POSSIBLE IN ANY HEAVIER SNOW SHOWERS OR SNOW SQUALLS.
THE COLD AIRMASS WILL SET THE STAGE FOR ONLY A SLIGHT RISE IN
TEMPERATURES ON MONDAY...WITH FALLING TEMPERATURES POSSIBLE IN THE
AFTERNOON PENDING CLOUD COVER AND ASSOCIATED SOLAR INSOLATION.
SEVERAL LOCATIONS MAY NOT REACH THE FREEZING MARK ON MONDAY...WITH
TEMPERATURES AVERAGING 10 TO 15 DEGREES BELOW NORMAL. THE COLDEST
LOW TEMPERATURES SO FAR THIS WINTER DURING THE START OF THE LONG
TERM PERIOD.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 317 AM EST SUN JAN 3 2016
THE MODELS WERE IN PRETTY GOOD AGREEMENT IN THE EXTENDED. THE FIRST
FEW HOURS OF THE PERIOD ARE EXPECTED TO FEATURE A FEW SNOW FLURRIES
ACROSS THE AREA...AS NORTHWESTERLY UPSLOPE FLOW BEHIND A DEPARTING
WEATHER SYSTEM BEGINS TO WIND DOWN. THE SNOW SHOULD BE GONE BY 3Z
TUESDAY. AFTER THAT...WE CAN EXPECT A PERIOD OF DRY AND GRADUALLY
WARMER WEATHER...WITH NO PRECIPITATION EXPECTED UNTIL THURSDAY
EVENING. THE GFS AND ECMWF MODELS BOTH HAVE A LARGE AREA OF LOW
PRESSURE FORMING OVER AND MOVING OUT OF THE WEST CENTRAL PLAINS
THURSDAY AND THURSDAY NIGHT. THIS SYSTEM IS ON TRACK TO MOVE ACROSS
THE MID MISSISSIPPI VALLEY REGION FRIDAY AND FRIDAY NIGHT AND INTO
THE WESTERN GREAT LAKES. AS THIS SYSTEM MAKES ITS WAY EASTWARD...A
SURGE OF MOISTURE OFF THE GULF OF MEXICO IS FORECAST TO PUSH INTO
THE TENNESSEE AND OHIO VALLEY REGIONS TOWARD THE END OF THE WEEK.
THIS MOISTURE...COMBINED WITH LIFT ASSOCIATED WITH THE APPROACHING
AREA OF LOW PRESSURE AND ITS SURFACE COLD FRONT...WILL BRING
WIDESPREAD RAIN SHOWERS TO EASTERN KENTUCKY. THERE MAY EVEN BE
ENOUGH LIFT AND MOISTURE LINGERING BEHIND THE DEPARTED AREA OF LOW
PRESSURE TO KEEP PRECIPITATION AROUND THROUGH THE UPCOMING WEEKEND.
HOWEVER...THE MODEL DATA WAS NOT IN THE BEST OF AGREEMENT REGARDING
HOW WELL CONDITIONS WILL BE SUITED FOR POST FRONTAL PRECIPITATION
FRIDAY NIGHT THROUGH SATURDAY NIGHT...SO THAT PART OF THE FORECAST
SHOULD BE TAKEN WITH A GRAIN OF SALT AT THIS POINT...AT LEAST UNTIL
THE MODELS COME INTO BETTER AGREEMENT.
TEMPERATURES IN THE EXTENDED ARE FORECAST TO BE WELL BELOW NORMAL
THE FEW FIRST COUPLE OF DAYS. LOW TEMPERATURES COULD EASILY FALL
INTO THE LOW TO MID TEENS ACROSS THE ENTIRE AREA ON TUESDAY MORNING
WITH HIGHS ON THAT DAY PROBABLY ONLY CLIMBING INTO THE MID TO UPPER
30S ACROSS THE AREA. A GRADUAL WARM UP IS EXPECTED FROM WEDNESDAY
ONWARD...WITH HIGHS EACH DAY REACHING THE 40S AND 50S AND OVERNIGHT
LOWS IN THE 30S AND 40S ENTERING THE WEEKEND. LOW TEMPERATURES
TUESDAY NIGHT AND WEDNESDAY NIGHT WILL STILL BE QUITE COLD WITH MIN
VALUES AROUND 20 EXPECTED FOR TUESDAY NIGHT AND AROUND 30 WEDNESDAY
NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1223 PM EST SUN JAN 3 2016
SITES STARTING THE PERIOD VFR AND MOST SITES WILL REMAIN THAT WAY
MUCH OF THE AFTERNOON INTO EARLY EVENING. TRACKING A MOSTLY MVFR
STRATUS DECK TO THE NORTH IN OH AND NUDGING INTO FAR NORTHERN KY.
SLOWLY CREEP THIS DECK SOUTH AFTERNOON NORTH AND TONIGHT FAR
SOUTHWEST. THEN FOCUS SHIFTS TO A APPROACHING UPPER LEVEL TROUGH
AND COLD FRONT THAT WILL BRING A CHANCE OF SNOW SHOWERS/SNOW
SQUALLS TO THE REGION MONDAY MORNING INTO THE AFTERNOON. GIVEN
THERE IS STILL SOME UNCERTAINTY WILL ONLY INTRODUCE SNOW SHOWERS
AT THE MORE NORTHERN SITE OF SYM...JKL...AND SYM. THESE SNOW
SHOWERS WILL LEAD TO SUDDEN REDUCTIONS IN VIS AND WOULD BE ONE OF
THE BIGGEST CONCERNS AVIATION WISE. A FEW GUSTS OF 15 KTS ARE
POSSIBLE AS WE MIX THIS AFTERNOON...THEN GUSTY CONDITIONS WILL BE
POSSIBLE WITH ANY SNOW SQUALLS THAT DEVELOP. OTHERWISE MOST SITES
WILL SEE LIGHT WINDS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...JP
LONG TERM...AR
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
1223 PM EST SUN JAN 3 2016
.UPDATE...
ISSUED AT 1043 AM EST SUN JAN 3 2016
THE BIGGEST ISSUE IN THE NEAR TERM WILL BE WHEN DOES THE STRATUS
MAKE IT INTO THE REGION...RIGHT NOW KEEPING THE MORE ROBUST
CLOUDS IN THE FAR NORTH. THE HRRR SEEMS TO HAVE A DECENT HANDLE ON
THIS SO WENT IN THAT DIRECTION. OTHERWISE MOST SHOULD REMAIN
MOSTLY SUNNY THOUGH MUCH OF THE DAY WITH TEMPS IN THE LOW TO MID
40S. UPDATED TEMPS/DEWS/WINDS WITH LATEST OBS AND TRENDS.
UPDATE ISSUED AT 735 AM EST SUN JAN 3 2016
HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT OBSERVATIONS. THE
VALLEYS IN THE COUNTIES NEAR INTERSTATE 64 REMAINED A BIT MORE
MIXED THAN ANTICIPATED AHEAD OF THE APPROACHING BOUNDARY SO
TEMPERATURES THERE WERE RAISED A BIT FOR THE NEXT COUPLE OF HOURS.
OTHERWISE...NO CHANGES WERE NECESSARY AT THIS TIME.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 258 AM EST SUN JAN 3 2016
EARLY THIS MORNING...A CLOSED LOW AND UPPER LEVEL TROUGH WAS
CENTERED OVER EASTERN CANADA AND EXTENDED SOUTH INTO THE GREAT
LAKES AND EASTERN CONUS. WITHIN THIS TROUGH A COUPLE OF SHORTWAVE
TROUGHS WERE ROTATING INTO AND THROUGH THE GREAT LAKES REGION WITH
ANOTHER FURTHER NORTH. AT THE SFC...A RIDGE OF HIGH PRESSURE WAS
CENTERED FROM THE SOUTHERN PLAINS INTO THE SOUTHEAST WITH ANOTHER
SFC HIGH ACROSS THE NORTHERN ROCKIES TO NORTHERN PLAINS AND
CANADIAN PLAINS REGIONS. IN BETWEEN A SFC TROUGH OR WEAK COLD
FRONT WAS NEARING THE OH VALLEY WHILE A STRONGER COLD FRONT
EXTENDED ACROSS THE NORTHERN GREAT LAKES FROM A SFC LOW OVER
EASTERN ONTARIO AND WESTERN QUEBEC.
LATE TONIGHT AND INTO THE DAY ON SUNDAY...THE FIRST WEAKER COLD
FRONT/SFC TROUGH IS EXPECTED TO MOVE ACROSS EASTERN KY WHILE THE
NEXT BOUNDARY IS EXPECTED TO SAG INTO THE CENTRAL GREAT LAKES AS
THE SFC LOW MOVES INTO THE CANADIAN MARITIMES. A COUPLE OF
SHORTWAVE TROUGHS WILL MOVE FROM THE GREAT LAKES AND INTO THE
NORTHEASTERN CONUS DURING THIS TIME...WITH ANOTHER MOVING INTO THE
LOWER OH VALLEY AND YET ANOTHER ONE MOVING INTO THE NORTHERN AND
WESTERN GREAT LAKES. ACROSS THE LOCAL AREA...TEMPERATURES SHOULD
AVERAGE NEAR TO SLIGHTLY ABOVE NORMAL FOR EARLY JANUARY AS THE
LOW LEVEL AND UPPER LEVEL FLOW BEGIN TO MOVE FROM SOUTHWESTERLY TO
WEST TO MORE WESTERLY TO EVEN NORTHWESTERLY. 850 MB TEMPS
INITIALLY WILL BE A COUPLE OF DEGREES ABOVE 0C BUT AS A SHORTWAVE
TROUGH APPROACHES WILL SLIDE TO BELOW 0C BY LATE AFTERNOON TO
EARLY EVENING.
TONIGHT INTO THE DAY ON MONDAY...A SHORTWAVE WILL MOVE ACROSS THE
LOWER OH VALLEY AND INTO THE APPALACHIANS EARLY IN THE PERIOD AND
BRING SOME LOW LEVEL MOISTURE AND LEAD TO A FURTHER DROP IN 850
MB TEMPS FROM THE SINGLE DIGITS BELOW 0C TO THE -10C TO -12C
RANGE. ANOTHER SHORTWAVE WILL BRING THE COLDEST OF THE 850 MB AIR
ACROSS THE AREA ON TUESDAY WITH 850 MB TEMPS FALLING TO ABOUT THE
-11C TO -14C RANGE.
THE MAIN FORECAST CONCERN AND CHALLENGE DURING THE SHORT TERM
PERIOD WILL BE THE UPPER LEVEL DISTURBANCES AND COLD FRONT THAT
MOVE ACROSS THE AREA OR APPROACH AREA LATE TONIGHT AND THEN MOVE
ACROSS THE REGION ON MONDAY AND ASSOCIATED SNOW SHOWERS AND OR
SNOW SQUALLS. STEEPENING LAPSE RATES AND INCREASING LOW LEVEL
MOISTURE SHOULD LEAD TO SOME FLURRIES OR ISOLATED TO SCATTERED SNOW
SHOWERS BY LATE TONIGHT.
THEN ON MONDAY...THE SNOW SHOW SHOWERS WILL PROBABLY BRING THE FIRST
MEASURABLE SNOW OF THE SEASON TO SEVERAL LOCATIONS. CURRENT MODEL
GUIDANCE HAS THE SNOW SQUALL PARAMETER PEAKING IN THE 2 TO 3 RANGE
GENERALLY DOWN THE MIDDLE OF THE CWA FROM 14Z TO 20Z OR MID TO LATE
MONDAY MORNING INTO EARLY TO MID AFTERNOON ON MONDAY. THE NAM
HOLDS ONTO THESE HIGHER INSTABILITY NUMBERS A BIT LONGER AND
FURTHER NORTH AS LATE AS 21Z ON MONDAY WHILE THE GFS AND ECMWF
HAVE DRIER AIR MOVING IN AND SHUTTING OF THE SNOW SHOWERS...SO
SOME UNCERTAINTY REMAINS IN THE EXACT TIMING AND LOCATIONS OF
THESE.
THE NAM HAS A PEAK IN QPF GENERALLY EAST OF A SYM TO JKL TO
I35 LINE TO NEAR LNP...WHILE THE GFS AND ECMWF ALSO HAVE A MORE
SUBTLE MAX ACROSS THE CENTRAL OR EASTERN PART OF THE AREA. AT
THIS POINT...WE HAVE WENT WITH A FEW HUNDREDTHS OF QPF A LITTLE
CLOSER TO OPERATION MODELS THAN THE SUPERBLEND...WITH GENERALLY A
TENTH TO LESS THAN A HALF OF AN INCH OF TOTAL SNOW. SOME ISOLATED
HIGHER AMOUNTS CANNOT BE RULED OUT IF A LOCATION WERE TO RECEIVE
MULTIPLE SNOW SHOWERS OR SOME NORTH TO SOUTH ORIENTED BANDING WERE
TO SET UP. OVERALL...THE HIGHER AMOUNTS SHOULD OCCUR ON THE
RIDGETOPS WHICH WILL REMAIN A DEGREE OR TWO COLDER THROUGHOUT THE
DAY ON MONDAY IN THE COLD ADVECTION PATTERN. THIS EVENT WILL
CONTINUE TO BE HIGHLIGHTED IN THE HWO AND IN THE WEATHER STORY...WITH
REDUCTIONS IN VISIBILITY AND SOME LIGHT QUICK ACCUMULATIONS
POSSIBLE IN ANY HEAVIER SNOW SHOWERS OR SNOW SQUALLS.
THE COLD AIRMASS WILL SET THE STAGE FOR ONLY A SLIGHT RISE IN
TEMPERATURES ON MONDAY...WITH FALLING TEMPERATURES POSSIBLE IN THE
AFTERNOON PENDING CLOUD COVER AND ASSOCIATED SOLAR INSOLATION.
SEVERAL LOCATIONS MAY NOT REACH THE FREEZING MARK ON MONDAY...WITH
TEMPERATURES AVERAGING 10 TO 15 DEGREES BELOW NORMAL. THE COLDEST
LOW TEMPERATURES SO FAR THIS WINTER DURING THE START OF THE LONG
TERM PERIOD.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 317 AM EST SUN JAN 3 2016
THE MODELS WERE IN PRETTY GOOD AGREEMENT IN THE EXTENDED. THE FIRST
FEW HOURS OF THE PERIOD ARE EXPECTED TO FEATURE A FEW SNOW FLURRIES
ACROSS THE AREA...AS NORTHWESTERLY UPSLOPE FLOW BEHIND A DEPARTING
WEATHER SYSTEM BEGINS TO WIND DOWN. THE SNOW SHOULD BE GONE BY 3Z
TUESDAY. AFTER THAT...WE CAN EXPECT A PERIOD OF DRY AND GRADUALLY
WARMER WEATHER...WITH NO PRECIPITATION EXPECTED UNTIL THURSDAY
EVENING. THE GFS AND ECMWF MODELS BOTH HAVE A LARGE AREA OF LOW
PRESSURE FORMING OVER AND MOVING OUT OF THE WEST CENTRAL PLAINS
THURSDAY AND THURSDAY NIGHT. THIS SYSTEM IS ON TRACK TO MOVE ACROSS
THE MID MISSISSIPPI VALLEY REGION FRIDAY AND FRIDAY NIGHT AND INTO
THE WESTERN GREAT LAKES. AS THIS SYSTEM MAKES ITS WAY EASTWARD...A
SURGE OF MOISTURE OFF THE GULF OF MEXICO IS FORECAST TO PUSH INTO
THE TENNESSEE AND OHIO VALLEY REGIONS TOWARD THE END OF THE WEEK.
THIS MOISTURE...COMBINED WITH LIFT ASSOCIATED WITH THE APPROACHING
AREA OF LOW PRESSURE AND ITS SURFACE COLD FRONT...WILL BRING
WIDESPREAD RAIN SHOWERS TO EASTERN KENTUCKY. THERE MAY EVEN BE
ENOUGH LIFT AND MOISTURE LINGERING BEHIND THE DEPARTED AREA OF LOW
PRESSURE TO KEEP PRECIPITATION AROUND THROUGH THE UPCOMING WEEKEND.
HOWEVER...THE MODEL DATA WAS NOT IN THE BEST OF AGREEMENT REGARDING
HOW WELL CONDITIONS WILL BE SUITED FOR POST FRONTAL PRECIPITATION
FRIDAY NIGHT THROUGH SATURDAY NIGHT...SO THAT PART OF THE FORECAST
SHOULD BE TAKEN WITH A GRAIN OF SALT AT THIS POINT...AT LEAST UNTIL
THE MODELS COME INTO BETTER AGREEMENT.
TEMPERATURES IN THE EXTENDED ARE FORECAST TO BE WELL BELOW NORMAL
THE FEW FIRST COUPLE OF DAYS. LOW TEMPERATURES COULD EASILY FALL
INTO THE LOW TO MID TEENS ACROSS THE ENTIRE AREA ON TUESDAY MORNING
WITH HIGHS ON THAT DAY PROBABLY ONLY CLIMBING INTO THE MID TO UPPER
30S ACROSS THE AREA. A GRADUAL WARM UP IS EXPECTED FROM WEDNESDAY
ONWARD...WITH HIGHS EACH DAY REACHING THE 40S AND 50S AND OVERNIGHT
LOWS IN THE 30S AND 40S ENTERING THE WEEKEND. LOW TEMPERATURES
TUESDAY NIGHT AND WEDNESDAY NIGHT WILL STILL BE QUITE COLD WITH MIN
VALUES AROUND 20 EXPECTED FOR TUESDAY NIGHT AND AROUND 30 WEDNESDAY
NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1223 PM EST SUN JAN 3 2016
SITES STARTING THE PERIOD VFR AND MOST SITES WILL REMAIN THAT WAY
MUCH OF THE AFTERNOON INTO EARLY EVENING. TRACKING A MOSTLY MVFR
STRATUS DECK TO THE NORTH IN OH AND NUDGING INTO FAR NORTHERN KY.
SLOWLY CREEP THIS DECK SOUTH AFTERNOON NORTH AND TONIGHT FAR
SOUTHWEST. THEN FOCUS SHIFTS TO A APPROACHING UPPER LEVEL TROUGH
AND COLD FRONT THAT WILL BRING A CHANCE OF SNOW SHOWERS/SNOW
SQUALLS TO THE REGION MONDAY MORNING INTO THE AFTERNOON. GIVEN
THERE IS STILL SOME UNCERTAINTY WILL ONLY INTRODUCE SNOW SHOWERS
AT THE MORE NORTHERN SITE OF SYM...JKL...AND SYM. THESE SNOW
SHOWERS WILL LEAD TO SUDDEN REDUCTIONS IN VIS AND WOULD BE ONE OF
THE BIGGEST CONCERNS AVIATION WISE. A FEW GUSTS OF 15 KTS ARE
POSSIBLE AS WE MIX THIS AFTERNOON...THEN GUSTY CONDITIONS WILL BE
POSSIBLE WITH ANY SNOW SQUALLS THAT DEVELOP. OTHERWISE MOST SITES
WILL SEE LIGHT WINDS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...JP
LONG TERM...AR
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
1043 AM EST SUN JAN 3 2016
.UPDATE...
ISSUED AT 1043 AM EST SUN JAN 3 2016
THE BIGGEST ISSUE IN THE NEAR TERM WILL BE WHEN DOES THE STRATUS
MAKE IT INTO THE REGION...RIGHT NOW KEEPING THE MORE ROBUST
CLOUDS IN THE FAR NORTH. THE HRRR SEEMS TO HAVE A DECENT HANDLE ON
THIS SO WENT IN THAT DIRECTION. OTHERWISE MOST SHOULD REMAIN
MOSTLY SUNNY THOUGH MUCH OF THE DAY WITH TEMPS IN THE LOW TO MID
40S. UPDATED TEMPS/DEWS/WINDS WITH LATEST OBS AND TRENDS.
UPDATE ISSUED AT 735 AM EST SUN JAN 3 2016
HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT OBSERVATIONS. THE
VALLEYS IN THE COUNTIES NEAR INTERSTATE 64 REMAINED A BIT MORE
MIXED THAN ANTICIPATED AHEAD OF THE APPROACHING BOUNDARY SO
TEMPERATURES THERE WERE RAISED A BIT FOR THE NEXT COUPLE OF HOURS.
OTHERWISE...NO CHANGES WERE NECESSARY AT THIS TIME.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 258 AM EST SUN JAN 3 2016
EARLY THIS MORNING...A CLOSED LOW AND UPPER LEVEL TROUGH WAS
CENTERED OVER EASTERN CANADA AND EXTENDED SOUTH INTO THE GREAT
LAKES AND EASTERN CONUS. WITHIN THIS TROUGH A COUPLE OF SHORTWAVE
TROUGHS WERE ROTATING INTO AND THROUGH THE GREAT LAKES REGION WITH
ANOTHER FURTHER NORTH. AT THE SFC...A RIDGE OF HIGH PRESSURE WAS
CENTERED FROM THE SOUTHERN PLAINS INTO THE SOUTHEAST WITH ANOTHER
SFC HIGH ACROSS THE NORTHERN ROCKIES TO NORTHERN PLAINS AND
CANADIAN PLAINS REGIONS. IN BETWEEN A SFC TROUGH OR WEAK COLD
FRONT WAS NEARING THE OH VALLEY WHILE A STRONGER COLD FRONT
EXTENDED ACROSS THE NORTHERN GREAT LAKES FROM A SFC LOW OVER
EASTERN ONTARIO AND WESTERN QUEBEC.
LATE TONIGHT AND INTO THE DAY ON SUNDAY...THE FIRST WEAKER COLD
FRONT/SFC TROUGH IS EXPECTED TO MOVE ACROSS EASTERN KY WHILE THE
NEXT BOUNDARY IS EXPECTED TO SAG INTO THE CENTRAL GREAT LAKES AS
THE SFC LOW MOVES INTO THE CANADIAN MARITIMES. A COUPLE OF
SHORTWAVE TROUGHS WILL MOVE FROM THE GREAT LAKES AND INTO THE
NORTHEASTERN CONUS DURING THIS TIME...WITH ANOTHER MOVING INTO THE
LOWER OH VALLEY AND YET ANOTHER ONE MOVING INTO THE NORTHERN AND
WESTERN GREAT LAKES. ACROSS THE LOCAL AREA...TEMPERATURES SHOULD
AVERAGE NEAR TO SLIGHTLY ABOVE NORMAL FOR EARLY JANUARY AS THE
LOW LEVEL AND UPPER LEVEL FLOW BEGIN TO MOVE FROM SOUTHWESTERLY TO
WEST TO MORE WESTERLY TO EVEN NORTHWESTERLY. 850 MB TEMPS
INITIALLY WILL BE A COUPLE OF DEGREES ABOVE 0C BUT AS A SHORTWAVE
TROUGH APPROACHES WILL SLIDE TO BELOW 0C BY LATE AFTERNOON TO
EARLY EVENING.
TONIGHT INTO THE DAY ON MONDAY...A SHORTWAVE WILL MOVE ACROSS THE
LOWER OH VALLEY AND INTO THE APPALACHIANS EARLY IN THE PERIOD AND
BRING SOME LOW LEVEL MOISTURE AND LEAD TO A FURTHER DROP IN 850
MB TEMPS FROM THE SINGLE DIGITS BELOW 0C TO THE -10C TO -12C
RANGE. ANOTHER SHORTWAVE WILL BRING THE COLDEST OF THE 850 MB AIR
ACROSS THE AREA ON TUESDAY WITH 850 MB TEMPS FALLING TO ABOUT THE
-11C TO -14C RANGE.
THE MAIN FORECAST CONCERN AND CHALLENGE DURING THE SHORT TERM
PERIOD WILL BE THE UPPER LEVEL DISTURBANCES AND COLD FRONT THAT
MOVE ACROSS THE AREA OR APPROACH AREA LATE TONIGHT AND THEN MOVE
ACROSS THE REGION ON MONDAY AND ASSOCIATED SNOW SHOWERS AND OR
SNOW SQUALLS. STEEPENING LAPSE RATES AND INCREASING LOW LEVEL
MOISTURE SHOULD LEAD TO SOME FLURRIES OR ISOLATED TO SCATTERED SNOW
SHOWERS BY LATE TONIGHT.
THEN ON MONDAY...THE SNOW SHOW SHOWERS WILL PROBABLY BRING THE FIRST
MEASURABLE SNOW OF THE SEASON TO SEVERAL LOCATIONS. CURRENT MODEL
GUIDANCE HAS THE SNOW SQUALL PARAMETER PEAKING IN THE 2 TO 3 RANGE
GENERALLY DOWN THE MIDDLE OF THE CWA FROM 14Z TO 20Z OR MID TO LATE
MONDAY MORNING INTO EARLY TO MID AFTERNOON ON MONDAY. THE NAM
HOLDS ONTO THESE HIGHER INSTABILITY NUMBERS A BIT LONGER AND
FURTHER NORTH AS LATE AS 21Z ON MONDAY WHILE THE GFS AND ECMWF
HAVE DRIER AIR MOVING IN AND SHUTTING OF THE SNOW SHOWERS...SO
SOME UNCERTAINTY REMAINS IN THE EXACT TIMING AND LOCATIONS OF
THESE.
THE NAM HAS A PEAK IN QPF GENERALLY EAST OF A SYM TO JKL TO
I35 LINE TO NEAR LNP...WHILE THE GFS AND ECMWF ALSO HAVE A MORE
SUBTLE MAX ACROSS THE CENTRAL OR EASTERN PART OF THE AREA. AT
THIS POINT...WE HAVE WENT WITH A FEW HUNDREDTHS OF QPF A LITTLE
CLOSER TO OPERATION MODELS THAN THE SUPERBLEND...WITH GENERALLY A
TENTH TO LESS THAN A HALF OF AN INCH OF TOTAL SNOW. SOME ISOLATED
HIGHER AMOUNTS CANNOT BE RULED OUT IF A LOCATION WERE TO RECEIVE
MULTIPLE SNOW SHOWERS OR SOME NORTH TO SOUTH ORIENTED BANDING WERE
TO SET UP. OVERALL...THE HIGHER AMOUNTS SHOULD OCCUR ON THE
RIDGETOPS WHICH WILL REMAIN A DEGREE OR TWO COLDER THROUGHOUT THE
DAY ON MONDAY IN THE COLD ADVECTION PATTERN. THIS EVENT WILL
CONTINUE TO BE HIGHLIGHTED IN THE HWO AND IN THE WEATHER STORY...WITH
REDUCTIONS IN VISIBILITY AND SOME LIGHT QUICK ACCUMULATIONS
POSSIBLE IN ANY HEAVIER SNOW SHOWERS OR SNOW SQUALLS.
THE COLD AIRMASS WILL SET THE STAGE FOR ONLY A SLIGHT RISE IN
TEMPERATURES ON MONDAY...WITH FALLING TEMPERATURES POSSIBLE IN THE
AFTERNOON PENDING CLOUD COVER AND ASSOCIATED SOLAR INSOLATION.
SEVERAL LOCATIONS MAY NOT REACH THE FREEZING MARK ON MONDAY...WITH
TEMPERATURES AVERAGING 10 TO 15 DEGREES BELOW NORMAL. THE COLDEST
LOW TEMPERATURES SO FAR THIS WINTER DURING THE START OF THE LONG
TERM PERIOD.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 317 AM EST SUN JAN 3 2016
THE MODELS WERE IN PRETTY GOOD AGREEMENT IN THE EXTENDED. THE FIRST
FEW HOURS OF THE PERIOD ARE EXPECTED TO FEATURE A FEW SNOW FLURRIES
ACROSS THE AREA...AS NORTHWESTERLY UPSLOPE FLOW BEHIND A DEPARTING
WEATHER SYSTEM BEGINS TO WIND DOWN. THE SNOW SHOULD BE GONE BY 3Z
TUESDAY. AFTER THAT...WE CAN EXPECT A PERIOD OF DRY AND GRADUALLY
WARMER WEATHER...WITH NO PRECIPITATION EXPECTED UNTIL THURSDAY
EVENING. THE GFS AND ECMWF MODELS BOTH HAVE A LARGE AREA OF LOW
PRESSURE FORMING OVER AND MOVING OUT OF THE WEST CENTRAL PLAINS
THURSDAY AND THURSDAY NIGHT. THIS SYSTEM IS ON TRACK TO MOVE ACROSS
THE MID MISSISSIPPI VALLEY REGION FRIDAY AND FRIDAY NIGHT AND INTO
THE WESTERN GREAT LAKES. AS THIS SYSTEM MAKES ITS WAY EASTWARD...A
SURGE OF MOISTURE OFF THE GULF OF MEXICO IS FORECAST TO PUSH INTO
THE TENNESSEE AND OHIO VALLEY REGIONS TOWARD THE END OF THE WEEK.
THIS MOISTURE...COMBINED WITH LIFT ASSOCIATED WITH THE APPROACHING
AREA OF LOW PRESSURE AND ITS SURFACE COLD FRONT...WILL BRING
WIDESPREAD RAIN SHOWERS TO EASTERN KENTUCKY. THERE MAY EVEN BE
ENOUGH LIFT AND MOISTURE LINGERING BEHIND THE DEPARTED AREA OF LOW
PRESSURE TO KEEP PRECIPITATION AROUND THROUGH THE UPCOMING WEEKEND.
HOWEVER...THE MODEL DATA WAS NOT IN THE BEST OF AGREEMENT REGARDING
HOW WELL CONDITIONS WILL BE SUITED FOR POST FRONTAL PRECIPITATION
FRIDAY NIGHT THROUGH SATURDAY NIGHT...SO THAT PART OF THE FORECAST
SHOULD BE TAKEN WITH A GRAIN OF SALT AT THIS POINT...AT LEAST UNTIL
THE MODELS COME INTO BETTER AGREEMENT.
TEMPERATURES IN THE EXTENDED ARE FORECAST TO BE WELL BELOW NORMAL
THE FEW FIRST COUPLE OF DAYS. LOW TEMPERATURES COULD EASILY FALL
INTO THE LOW TO MID TEENS ACROSS THE ENTIRE AREA ON TUESDAY MORNING
WITH HIGHS ON THAT DAY PROBABLY ONLY CLIMBING INTO THE MID TO UPPER
30S ACROSS THE AREA. A GRADUAL WARM UP IS EXPECTED FROM WEDNESDAY
ONWARD...WITH HIGHS EACH DAY REACHING THE 40S AND 50S AND OVERNIGHT
LOWS IN THE 30S AND 40S ENTERING THE WEEKEND. LOW TEMPERATURES
TUESDAY NIGHT AND WEDNESDAY NIGHT WILL STILL BE QUITE COLD WITH MIN
VALUES AROUND 20 EXPECTED FOR TUESDAY NIGHT AND AROUND 30 WEDNESDAY
NIGHT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 739 AM EST SUN JAN 3 2016
VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR ABOUT THE FIRST 12
HOURS OF THE PERIOD...WITH INCREASING LOW LEVEL MOISTURE POSSIBLY
BRINGING SOME MVFR CIGS TO NORTHERN LOCATIONS BY 0Z. MVFR CIGS
SHOULD SPREAD ACROSS THE AREA LATE IN THE PERIOD...BEHIND AN
INITIAL COLD FRONT AND IN ADVANCE OF AN APPROACHING STRONGER COLD
FRONT AND ASSOCIATED UPPER LEVEL DISTURBANCE. SOME -SHSN OR
FLURRIES ARE POSSIBLE BETWEEN 6Z AND 12Z...BUT CONFIDENCE IN
TIMING AND LOCATION WAS NOT HIGH ENOUGH TO INCLUDE ATTM. WINDS
WILL BE FROM THE SOUTHWEST TO WEST AT GENERALLY 10 KT OR LESS
THROUGH THE FIRST 6 HOURS OF THE PERIOD...BEFORE BECOMING WEST TO
NORTHWEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...JP
LONG TERM...AR
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
438 PM EST SUN JAN 3 2016
.SYNOPSIS...
LOW PRESSURE WILL MOVE SLOWLY EAST ACROSS SOUTHERN QUEBEC...DRIVING
AN ARCTIC COLD FRONT THROUGH THE REGION THIS EVENING. HIGH
PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST TONIGHT AND CREST
OVER THE REGION ON TUESDAY. THE HIGH WILL SHIFT OFFSHORE SOUTH OF
NEW ENGLAND ON WEDNESDAY...HOLDING OFF THE COAST THROUGH THURSDAY.
LOW PRESSURE WILL MOVE NORTH UP THE EAST COAST FRIDAY THROUGH
SATURDAY. ANOTHER AREA OF LOW PRESSURE WILL MOVE UP THE MID
ATLANTIC COAST ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
UPDATE...A FEW MINOR CHANGES AFTER ANALYZING SOME OF THE LATEST
HI-RES MODEL GUIDANCE. WIND SHIFT IS OCCURRING ALONG THE ST.
LAWRENCE AND IN THE ADIRONDACKS. AS THIS COLD FRONT DROPS SWD
THIS EVENING...SN SHOWERS WILL INTENSIFY ALONG THE LEADING EDGE.
LATEST RUNS OF THE HRRR INDICATE HOURLY SNWFL RATES OF 0.5 TO 1
INCH PER HOUR. THESE RATES ARE UNLIKELY TO LAST A FULL HOUR...BUT
FOR THE BRIEF THEY ARE OCCURRING VISIBILITIES IN NRN NH AND WRN ME
WILL BE NEAR ZERO. HAVE ISSUED A SPECIAL WX STATEMENT THRU 7 PM TO
MENTION THIS THREAT. ALSO HAVE TO CONSIDER ABOVE FREEZING TEMPS
TODAY RAPIDLY DROPPING BELOW BEHIND THE FRONT. REFREEZING WILL BE
AN ISSUE FOR UNTREATED ROADS.
PREVIOUS DISCUSSION...SNOW SHOWERS WILL CONTINUE IN THE MOUNTAINS
THIS EVENING AS LOW PRESSURE EXITS INTO THE CANADIAN MARITIMES. A
TRAILING ARCTIC FRONT WILL PUSH SOUTHWARD THROUGH THE FORECAST
AREA THIS EVENING. WITH STRONG COLD AIR ADVECTION...UPPER LEVEL
SUPPORT AND SUFFICIENT LOW LEVEL MOISTURE...ISOLATED SQUALLS WILL
BE POSSIBLE AS WELL ACROSS THE HIGHER TERRAIN. FURTHER
SOUTH...BREAKS IN THE CLOUD COVER WILL CONTINUE OVER THE
DOWNSLOPING REGIONS.
FAR NORTHERN AREAS WILL DROP DOWN TO NEAR ZERO BY MORNING. WITH
GUSTY NORTHWESTERLY WINDS...WIND CHILL VALUES WILL FALL INTO THE
-10 TO -15 RANGE OR LOWER.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
ARCTIC AIR WILL BE FULLY ESTABLISHED ON MONDAY WITH THE GREATEST
AMOUNT OF UPSLOPE CLOUDINESS CONTINUING OVER THE NORTHWEST FACING
HIGHER TERRAIN.
TEMPERATURES WILL CONTINUE TO FALL THROUGH MONDAY EVENING AS H850
TEMPERATURES DROP TO AROUND -18C IN THE MOUNTAINS. WITH A
NORTHWEST BREEZE AT AROUND 10 TO 15 MPH...EXPECT WIND CHILL VALUES
TO DROP INTO THE -20 TO -30 RANGE. WIND CHILL ADVISORIES MAY BE
NEEDED.
THIS WILL BE THE COLDEST NIGHT SO FAR OF THIS WINTER SEASON. WITH
CLEAR SKIES MONDAY NIGHT...TEMPERATURES WILL FALL TO AROUND -10 IN
THE NORTH AND SINGLE NUMBERS IN THE SOUTH.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE WEEK IS STILL LOOKING PRETTY QUIET ACROSS THE REGION IN THE
EXTENDED FORECAST AS HIGH PRESSURE REMAINS IN CONTROL OVER THE
NORTHEAST....
WINDS WILL FINALLY DIMINISH ACROSS THE AREA AS HIGH PRESSURE
CONTINUES TO BUILD IN FROM THE WEST ON TUESDAY. ASIDE FROM A FEW
HIGH CLOUDS...EXPECT A MOSTLY SUNNY BUT COLD DAY. HIGHS WILL RANGE
FROM THE LOWER TO MID TEENS NORTH TO THE MID TEENS TO LOWER 20S
SOUTH.
HIGH PRESSURE WILL SETTLE ALONG THE MID ATLANTIC COAST SOUTH OF NEW
ENGLAND TUESDAY NIGHT. CLEAR SKIES AND VERY DRY AIRMASS WILL
ALLOW FOR GOOD RADIATIONAL COOLING. LOWS WILL BOTTOM OUT AT ZERO
TO 5 ABOVE NORTH AND 5 TO 15 SOUTH.
HIGH PRESSURE WILL GENERALLY REMAIN ANCHORED SOUTH OF NEW ENGLAND
WEDNESDAY AND THURSDAY WITH RETURN FLOW BRINGING MODERATING TEMPS.
WEDNESDAY WILL FEATURE VARIABLE HIGH CLOUDS WITH HIGHS FROM THE
MID 20S TO MID 30S. THURSDAY WILL BE A LITTLE WARMER WITH MORE IN
THE WAY OF HIGH CLOUDS. HIGHS WILL RANGE THROUGH THE 30S TO NEAR
40.
DECAYING FRONTAL BOUNDARY WILL WASH OUT AS IT SAGS SOUTH INTO THE REGION
ON FRIDAY. NET RESULT WILL BE VARIABLE CLOUDINESS WITH
LITTLE CHANGE IN TEMPS FROM THURSDAY. QUIET WEATHER WILL CONTINUE
FRIDAY NIGHT AS HIGH PRESSURE BUILDS BY TO THE NORTH.
UNSETTLED WEATHER WILL MAKE A RETURN FOR THIS WEEKEND BUT
MODELS STILL COMING INTO LINE ON SHORTWAVE LIFTING OUT OF THE
GREAT LAKES. AFTER A PARTLY SUNNY START TO THE DAY EXPECT
INCREASING CLOUDS WITH SOME LIGHT SNOW SHIFTING IN FROM THE
SOUTHWEST IN AFTERNOON. GFS SHOWING STRONG COLD AIR DAMMING
PERSISTING INTO SATURDAY NIGHT WITH LITTLE IN THE WAY OF WARMING
ALOFT SO WOULD EXPECT SNOW POSSIBLY MIXING WITH SLEET IN SOUTHERN
ZONES SATURDAY NIGHT.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
SHORT TERM...MAINLY VFR CONDITIONS. HOWEVER...AREAS OF IFR AND
POSSIBLY LIFR CONDITIONS IN THE MOUNTAINS THROUGH THIS EVENING
WITH SNOW SHOWERS AND ISOLATED SNOW SQUALLS.
LONG TERM...VFR TUESDAY THROUGH FRIDAY.
&&
.MARINE...
SHORT TERM...SMALL CRAFT ADVISORIES HAVE BEEN EXTENDED THROUGH
MONDAY NIGHT. INCREASING GRADIENT AND STRONG COLD AIR ADVECTION
WILL CONTINUE OVER THE WATERS. WIND GUSTS OUT OF THE NORTHWEST
WILL TOP 30 KTS AT TIMES.
LONG TERM...NO FLAGS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR ANZ150-152-154.
&&
$$
NEAR TERM...LEGRO
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
625 PM EST MON JAN 4 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 359 PM EST MON JAN 4 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW THAT THE TROF THAT DROPPED
INTO THE GREAT LAKES REGION OVER THE WEEKEND IS WEAKENING AND
QUICKLY SHIFTING INTO NEW ENGLAND IN RESPONSE TO A STRONG RIDGE
MOVING OUT OVER THE PLAINS AND SCNTRL CANADA. 12HR 500MB HEIGHT
RISES WERE 90M/160M AT KINL/CWPL RESPECTIVELY AT 12Z TODAY. THE
ASSOCIATED SFC HIGH PRES RIDGE IS ALREADY EXITING TO THE E OF THE
FCST AREA AND SW RETURN FLOW IS RAPIDLY INCREASING TO THE W AND NW
IN THE TIGHTENING PRES GRADIENT BTWN THE DEPARTING RIDGE AND LOW
PRES APPROACHING HUDSON BAY. AS A RESULT...LINGERING/DIMINISHING LES
OFF LAKE SUPERIOR HAS MOSTLY SHIFTED OFFSHORE EARLY THIS AFTN WITH
ONLY A FEW RESIDUAL FLURRIES OVER THE NCNTRL. FLURRIES HAVE ALSO
MOVED ONSHORE AROUND MENOMINEE AS WINDS VEER OVER NRN LAKE MI.
A QUIET SHORT TERM PORTION OF THE FCST IS SHAPING UP...AT LEAST PCPN-
WISE. SW FLOW WILL DOMINATE BTWN THE HIGH PRES RIDGE SHIFTING TO THE
E COAST AND LOW PRES TRACKING ACROSS HUDSON BAY. DESPITE
WAA/ISENTROPIC ASCENT...FCST SOUNDINGS SHOW COLUMN REMAINING VERY
DRY...SO PCPN WON`T BE AN ISSUE UNDER THE WAA REGIME TONIGHT/TUE.
HOWEVER...AS WINDS VEER TO THE SW OVER NRN LAKE MI...SOME FLURRIES
SHOULD BRUSH AREAS NEAR LAKE MI THIS EVENING...AND ONCE THE SW FLOW
LOCKS IN...THE WRN EDGE OF LIGHT LES/FLURRIES MAY OCCASIONALLY
AFFECT SE LUCE COUNTY OVERNIGHT. ELSEHWERE...AN ISSUE TONIGHT/TUE IS
THE POTENTIAL FOR LOW CLOUDS TO DEVELOP AS NAM/RAP SHOW SHALLOW
MOISTENING IN THE NEAR SFC LAYER...THE RAP MUCH SOONER THAN THE NAM.
SFC OBS/3.9 MICRON IMAGERY DO SHOW LOW STRATUS OVER MUCH OF IA INTO
PORTIONS OF SCNTRL MN THIS AFTN. TRAJECTORIES INITIALLY CARRY THIS
STRATUS NORTHWARD...BUT OVER TIME THESE LOW CLOUDS MAY SLIP INTO THE
HIGH TERRAIN OF WRN UPPER MI LATE TONIGHT OR TUE MORNING. WILL WAIT
TO SEE HOW THE STRATUS EVOLVES THIS EVENING WITHIN STRENGTHENING LOW-
LEVEL FLOW BEFORE SHIFTING TO A MUCH MORE PESSIMISTIC SKY COVER FCST
OVER THE HIGHER TERRAIN OF THE W HALF. ON TUE...TIGHT PRES GRADIENT
WILL LEAD TO GUSTY WINDS. LIMITED MIXING DEPTH WILL WORK TO KEEP
WINDS IN CHECK...BUT STILL EXPECT SOME GUSTS TO 30-35MPH OVER THE
HIGHER TERRAIN...DOWNSLOPE AREAS NEAR LAKE SUPERIOR AND DOWNWIND OF
LAKE MICHIGAN.
AS FOR TEMPS...TEMPS WILL HAVE A CHANCE TO FALL INITIALLY THIS
EVENING BEFORE GRADIENT TIGHTENS. TOUGH TO SAY HOW LOW TEMPS WILL
GET...BUT THE FAR E SHOULD HAVE THE BEST CHANCE FOR A QUICK FALL
THIS EVENING BEFORE CLOUDS AND/OR WINDS INCREASE AS THAT AREA IS
CLOSER TO THE DEPARTING HIGH PRES RIDGE. WILL SHOW TEMPS AS LOW AS
AROUND 5F ABOVE IN LUCE COUNTY/PORTIONS OF SCHOOLCRAFT COUNTY.
TRADITIONAL COLD SPOTS OVER THE INTERIOR W SHOULD SLIP JUST BLO 10F.
EXPECT HIGHS ON TUE IN THE MID/UPPER 20S FOR THE MOST PART.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 323 PM EST MON JAN 4 2016
NO SIGNIFICANT WEATHER CONCERNS FOR THE LONG TERM FORECAST...BUT
THERE WILL BE SEVERAL NUISANCE EVENTS THAT COULD LEAD TO OCCASIONAL
PERIODS OF SLIPPERY ROADS.
HIGH PRESSURE WILL BE OVER THE ATLANTIC SEABOARD AT THE START OF
THE LONG TERM PERIOD...WHILE A SHORTWAVE AND SURFACE LOW MOVE
THROUGH SOUTHERN HUDSON BAY. A WEAKENING TROUGH ASSOCIATED WITH THE
LOW WILL BE SLIDING SOUTHEAST TOWARDS THE AREA TUESDAY NIGHT AND
INTO WEDNESDAY (ACROSS NORTHWEST ONTARIO)...EVENTUALLY SETTLING
OVER WESTERN LAKE SUPERIOR. THAT TROUGH WILL REMAIN NEARLY
STATIONARY THROUGH THURSDAY...AS A WEAK SHORTWAVE LIFTS NORTHEAST
ACROSS THE UPPER GREAT LAKES REGION. EXPECT LIMITED PRECIPITATION
ALONG THE FRONT TUESDAY NIGHT INTO WEDNESDAY BEFORE THE SHORTWAVE
MOVES THROUGH...WITH THE BEST CHANCES TIED TO SOME LAKE ENHANCEMENT
NEAR THE KEWEENAW PENINSULA. THE GENERAL IDEA WITH THE HIGHER
RESOLUTION MODELS IS TO KEEP THE TROUGH OVER WESTERN LAKE SUPERIOR
AND THE HEAVIER BAND JUST BRUSHING THE NORTHERN PORTIONS OF
KEWEENAW COUNTY. WILL FOLLOW THAT IDEA WITH THE POPS/SNOW
FORECAST...BUT WILL NEED TO KEEP AN EYE ANY TRENDS TO THE SOUTH AS
THAT WOULD LEAD TO SOME HEAVIER SNOW AFFECTING KEWEENAW COUNTY.
OTHERWISE...EXPECT LOW CLOUDS TO SPREAD INTO THE AREA UNDER THE
STRONG INVERSION JUST ABOVE 900MB TUESDAY EVENING...ASSUMING THEY
DON/T OCCUR BEFORE THAT AS SHOWN ON THE NAM. WITH THE LOW CLOUD
POTENTIAL AND CLOUDS FROM THE TROUGH...SHOULD SEE A MOSTLY CLOUDY
PERIOD TUESDAY NIGHT INTO WEDNESDAY.
PRECIPITATION SHOULD MOVE INTO THE WESTERN U.P. WEDNESDAY
AFTERNOON/EVENING ALONG THE STALLED TROUGH AND ASSOCIATED WITH
INCREASING MOISTURE AND MID LEVEL Q-VECTOR CONVERGENCE WITH THE
SHORTWAVE. WILL LIKELY SEE TWO WAVES...WITH THE FIRST AN ELONGATED
WSW TO ENE AREA OF SNOW STRETCHING ACROSS THE WEST/CENTRAL U.P. AND
ASSOCIATED WITH 850-750MB FGEN FORCING. THE SECOND PUSH ARRIVES
LATE WEDNESDAY NIGHT INTO THURSDAY AS THE SHORTWAVE AND 850-700MB
WARM AIR ADVECTION PUSHES THROUGH. EXPECT ALL OF THIS PRECIP TO
FALL AS SNOW LATE WEDNESDAY AFTERNOON INTO THURSDAY...BUT WITH MUCH
OF THE FORCING BELOW THE DGZ...THINK SNOW-TO-LIQUID RATIOS WILL BE
RIGHT AROUND 10-1 FOR MUCH OF THE EVENT (MAYBE SLIGHTLY LOWER
INITIALLY AND SLIGHTLY HIGHER TOWARDS THE END). THUS...WITH QPF
AMOUNTS OF 0.1 TO 0.25 OVER THE WEST/CENTRAL U.P. WOULD EXPECT
SNOWFALL AMOUNTS AROUND 2 INCHES FOR MUCH OF THE WEST/CENTRAL U.P.
SHOULD SEE A BRIEF BREAK BEFORE THE NEXT WAVE OF LIGHT PRECIPITATION
MOVES NORTHEAST INTO THE AREA FRIDAY INTO SATURDAY AS A WEAK LOW
LIFTS FROM MISSOURI AT 12Z FRIDAY TO JAMES BAY BY 12Z SUNDAY. AT
THIS POINT...IT LOOKS LIKE THE BEST FORCING WILL BE OVER THE EASTERN
U.P. WITH THE BEST PUSH OF SNOW MOVING THROUGH DURING THE DAY ON
FRIDAY (GENERALLY 1-3 INCHES). THERE MAY BE ENOUGH LOW LEVEL WARMING
TO RAISE WETBULB0 HEIGHTS TO LEAD TO A LITTLE BIT OF RAIN MIXING IN
WITH THE SNOW ALONG THE BAY OF GREEN BAY SHORELINE SOUTH OF
ESCANABA...SO DID INCLUDE A SLIGHT CHANCE TO CHANCE OF RAIN THERE.
WHILE THE LOW IS FAIRLY WEAK AND BRINGS SOME LIGHT SNOW FRIDAY
INTO FRIDAY NIGHT...A STRONG WAVE FROM THE ARCTIC WILL BE DIVING
SOUTH ACROSS THE CANADIAN PRAIRIES AND BE MOVING TOWARDS THE GREAT
LAKES REGION FOR THE SECOND HALF OF THE WEEKEND AND FOR EARLY NEXT
WEEK. THAT WILL LEAD TO A SIGNIFICANT TRANSITION IN TEMPERATURES...
FROM THE LOWER 30S FOR THE LATER HALF OF THIS WEEK TO HIGHS IN THE
SINGLE DIGITS TO LOWER TEENS ABOVE ZERO ON MONDAY. THAT COLD AIR
WILL ALSO MARK THE FIRST TIME OUR OFFICE WILL FALL BELOW ZERO SINCE
MARCH 28...2015. THROUGH JANUARY 3...THAT MAKES A 281 DAY STREAK
AND IS CURRENTLY TIED FOR THE 16TH LONGEST STREAK. IF THE CURRENT
FORECAST HOLDS...WE WILL MAKE IT TO AROUND 288 OR 289 DAYS...WHICH
WOULD BE RIGHT AROUND THE 9TH LONGEST STREAK OF TEMPERATURES AT OR
ABOVE ZERO. THAT COLD AIR (850MB TEMPS FALLING TO -24C ON SUNDAY)
WILL KICK THE LAKE EFFECT MACHINE BACK INTO GEAR FOR THE AREA...BUT
THE COLD TEMPERATURES WILL KEEP THE CLOUD GENERALLY ABOVE THE DGZ
LEADING TO SMALLER FLAKES. THAT WILL KEEP SNOWFALL AMOUNTS IN CHECK
AND LIKELY WOULD ONLY SEE ADVISORY AMOUNTS IN THE TRADITIONAL
WEST-NORTHWEST WIND SNOWBELTS. THE GREATER IMPACT WITH THE SMALLER
FLAKES WILL BE THE REDUCED VISIBILITIES...ESPECIALLY IF THERE IS
ENOUGH WIND TO BLOW THE SNOW AROUND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 624 PM EST MON JAN 4 2016
INCRSG SW WIND TNGT ABOVE LLVL INVRN ENHANCED BY NOCTURNAL COOLING
WL RESULT IN LLWS AT ALL 3 SITES TNGT INTO TUE MRNG. HOW QUICKLY
THIS SW FLOW TAPS MOISTER AIR WELL TO THE SW OF UPR MI IS ANOTHER
FCST CONCERN. RIGHT NOW...EXPECT VFR CONDITIONS TO PREVAIL THRU THE
FCST PERIOD...WITH DOWNSLOPE NATURE OF THE SW FLOW HELPING TO
MAINTAIN LOWER RH. DID SHOW SOME LO CLDS MOVING INTO IWD LATE TUE
AFTN AS THE MOISTER AIR SLOWLY ADVECTS TO THE NE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EST MON JAN 4 2016
TIGHTENING PRES GRADIENT BTWN DEPARTING HIGH PRES RIDGE AND LOW PRES
MOVING OVER HUDSON BAY WILL RESULT IN SW WINDS INCREASING TO GALES
TONIGHT ACROSS LAKE SUPERIOR. THE GALES WILL CONTINUE TUE BEFORE
WINDS BEGIN TO DIMINISH TUE NIGHT. WINDS WILL DIMINISH FURTHER
WED/THU TO MOSTLY UNDER 20KT AS A LOW PRES TROF SETTLES OVER THE
UPPER GREAT LAKES. WINDS WILL INCREASE SOME ON FRI/SAT AS LOW PRES
LIFTS NE INTO THE GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TUESDAY TO 1 AM EST WEDNESDAY FOR
LSZ265>267.
GALE WARNING FROM 10 PM EST /9 PM CST/ THIS EVENING TO 10 PM EST
/9 PM CST/ TUESDAY FOR LSZ162.
GALE WARNING FROM 10 PM THIS EVENING TO 1 AM EST WEDNESDAY FOR
LSZ263-264.
GALE WARNING FROM 6 AM TUESDAY TO 1 AM EST WEDNESDAY FOR LSZ243-
244.
LAKE MICHIGAN...
GALE WARNING FROM 7 AM TUESDAY TO 1 AM EST WEDNESDAY FOR LMZ221-
248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
255 PM EST SUN JAN 3 2016
.UPDATE...
ISSUED AT 1036 AM EST SUN JAN 3 2016
LES SEEMS TO BE BECOMING A LITTLE MORE DISORGANIZED THIS MORNING
/ALTHOUGH STILL LOCALLY HEAVY/ AS THE PBL WINDS BACK SLIGHTLY AND
INVERSION CRASHES BEHIND THE SHORT WAVE EARLIER THIS MORNING. WITH
WINDS BEING 330-340...EXPECT THE BEST SNOW TO REMAIN OVER WESTERN AND
CENTRAL ALGER COUNTY AND PERHAPS INTO NORTHWEST SCHOOLCRAFT NEAR
STEUBEN WHERE A LOCALIZED 3 TO 5 INCHES ARE POSSIBLE TODAY. AS
SUCH...WILL KEEP ALL ADVISORIES AS IS. AS THE NEXT SHORT WAVE OVER
ONTARIO MOVES ACROSS TONIGHT...EXPECT THE PBL FLOW TO VEER TO N-NE AS
THE INVERTED SFC TROUGH PASSES SOUTH...WHILE THE INVERSION RAISES
RATHER SIGNIFICANTLY. THIS SHOULD ALLOW FOR A BURST OF HEAVIER SNOW
TO MOVE INTO MARQUETTE COUNTY THIS EVENING INTO THE OVERNIGHT HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 526 AM EST SUN JAN 3 2016
WV IMAGERY AND RAP ANALYSIS INDICATED NNW MID/UPPER LEVEL FROM CNTRL
CANADA THROUGH THE WRN GREAT LAKES DOWNSTREAM FROM A MID/UPPER LEVEL
RIDGE FROM THE CNTRL ROCKIES INTO ALBERTA. ONE WEAK SHORTWAVE TROUGH
THAT BROUGHT A COLD FRONT THROUGH UPPER MI WAS SLIDING TO THE SE OF
THE AREA WHILE ANOTHER UPSTREAM SHRTWV WAS LOCATED OVER NE MANITOBA.
CAA IN THE WAKE OF THE FRONT DROPPING 850 MB TEMPS TO AROUND -15C
HAS ALONG WITH INCREASING NNW WINDS HAS BROUGHT AN INCREASE IN LES
INTO N CNTRL UPPER MI WITH A FEW MODERATE TO HEAVY BANDS.
HOWEVER...THE WINDS HAVE SHIFTED ENOUGH TO LIMIT THE
ORGANIZATION/INTENSITY OF THE BAND AND RESIDENCE TIME IN ANY ONE
LOCATION. SO...ACCUMULATIONS OVERNIGHT HAVE BEEN LIGHT.
TODAY...THE MODELS WERE IN GOOD AGREEMENT THAT LOW LEVEL WINDS WILL
BACK IN ADVANCE OF THE SHRTWV MOVING SSE THROUGH NW ONTARIO. THIS
WILL SHIFT THE BEST LOW LEVEL CONV FROM ERN MARQUETTE COUNTY TOWARD
MUNISING THIS AFTERNOON. ALTHOUGH UPSTREAM MOISTURE IS
FAVORABLE...INVERSION HEIGHTS NEAR 5K-6K FT WILL KEEP THE LES IN
CHECK. SNOWFALL AMOUNTS IN THE 2 TO 4 INCH RANGE ARE STILL EXPECTED
BUT WITH THE HIGHEST TOTALS OVER WRN ALGER COUNTY. SNOW SHOWERS WILL
ALSO BE LIKELY ALONG THE REST OF THE LAKE SUPERIOR SHORE FAVORED BY
NNW FLOW BUT WITH LOWER INVERSION HEIGHTS AND/OR A SHORTER FETCH
ACCUMULATIONS OF ONLY AN INCH OR TWO ARE EXPECTED.
TONIGHT...AS THE SHRTWV MOVES IN FROM LATE AFTERNOON INTO THIS
EVENING WITH 700 MB TEMPS DROPPING TO NEAR -24C...LES WILL INCREASE
AS INVERSION HEIGHTS CLIMB TO 8K-10K FT WITH LAKE INDUCED CAPE
VALUES TO 500 J/KG. WITH THE DGZ IN MID PORTION OF THE CONVECTIVE
LAYER...SLR VALUES SHOULD ALSO EXCEED 20/1. SNOWFALL RATES AOA 1
INCH/HOUR ARE EXPECTED AS THE AREA OF STRONGEST LOW LEVEL CONV
SHIFTS BACK TO THE WEST INTO MARQUETTE COUNTY AS WINDS VEER FROM NNW
TO NNE. EVEN THOUGH THE MOST FAVORABLE CONDITIONS ONLY LAST A FEW
HOURS...ADDITIONAL ACCUMULATIONS IN THE 2 TO 5 INCH RANGE ARE
LIKELY. ACCUMULATIONS OF 1 TO 3 INCHES WILL ALSO BE POSSIBLE OVER
THE REST OF NRN UPPER MI. THE SHRTWV WILL ALSO BRING INLAND
LOCATIONS SOME LIGHT SNOW AMOUNTS OF AN INCH OR LESS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 251 PM EST SUN JAN 3 2016
...SOME SNOW WED AND WED NIGHT THEN ANOTHER CHANCE OF WIDESPREAD
SNOW OR MIXED PRECIP FRI INTO SAT...
QUIET TO START THE LONG TERM THEN IT BECOMES MORE ACTIVE AS THE
FIRST FULL WEEK OF 2016 PROGRESSES. HIGH PRESSURE RIDGE DROPPING
SOUTHEAST WILL BE OVER THE OHIO VALLEY ON MONDAY NIGHT. DRY WEATHER
SHOULD LAST INTO TUE...THOUGH SW WINDS AND LOW-LEVEL MOISTENING OFF
LK MICHIGAN COULD LEAD TO LIGHT LAKE EFFECT OVER FAR EAST CWA.
DESPITE MOISTURE DEPTH NOT EVEN EXCEEEDING 2KFT...TEMPS BLO -10C IN
THE MOIST LAYER SHOULD LIMIT FZDZ AND KEEP PTYPE SNOW.
OTHERWISE...SHOULD SEE FILTERED SUNSHINE OVER REST OF CWA WITH SCT-
BKN HIGH CLOUDS. INVERSION ONLY UP TO H9 ON TUE SO STRONG WINDS
ALOFT OVER 40 MPH SHOULD NOT MIX DOWN. MAY SEE GUSTS 20-30 MPH
DURING AFTN THOUGH. WITH SOME SUN HIGH TEMPS WILL MAKE IT TO THE MID-
UPR 20S INLAND AND COULD REACH LOW 30S NEAR LK SUPERIOR.
TUE NIGHT INTO WED...STRONG SHORTWAVE TROUGH CROSSES HUDSON BAY WITH
ASSOCIATED SFC TROUGH MOVING FM WESTERN LK SUPERIOR ACROSS AT LEAST
WESTERN UPR MICHIGAN. WEAK WIND SHIFT NOTED AT H85 WITH POCKET OF
COOLER AIR /H85 TEMPS BLO -10C/ MOVING ACROSS LK SUPERIOR. MAY SEE
LIGHT LAKE EFFECT/FLURRIES OVER KEWEENAW WITH WESTERLY WINDS. DUE TO
INCREASING TEMP GRADIENT AT H85...RIBBON OF FRONTOGENESIS FORMS
SOUTHERN MN INTO WESTERN UPR MICHIGAN. FGEN MAY BE ENHANCED FURTHER
DUE TO RIGHT ENTRANCE JET FORCING WITH JET STREAK OVER QUEBEC INTO
NORTHERN ONTARIO. AREA OF LGT SNOW IS FURTHER ENHANCED BY LARGER
SCALE LIFT FM SHORTWAVE/DEEP LAYER Q-VECTOR CONVERGENCE AND WAVE OF
LOW PRESSURE THAT APPROACH FM THE NORTHERN PLAINS AND RIDE ALONG THE
PRE-EXISTING SFC TROUGH. WHOLE SETUP COULD YIELD WIDESPREAD LIGHT TO
MODERATE SNOW AMOUNTS SOMEWHERE OVER UPR MICHIGAN. MODELS ARE NOT IN
AGREEMENT WITH OTHER MODELS OR EVEN PREVIOUS RUNS FM SAME MODEL
WHERE VARIOUS FORCING LINKS UP FOR THAT STRIPE OF MODERATE SNOW.
WILL BE SOMETHING TO KEEP AWARE OF FOR LATE WED INTO WED NIGHT.
SHORTWAVE TROUGH HEADS EAST ON THU AND EXPECT SNOW TO DIMINISH FM
WEST TO EAST AS A RESULT. WEAK SFC TROUGH SHOULD REMAIN VCNTY OF THE
UPPER GREAT LAKES BUT OVERALL SHOULD BE DOWNWARD TREND FOR THE SNOW
THU AFTN INTO THU NIGHT AS SHORTWAVE RIDGE CROSSES. DEPENDING ON
LOCATION OF SFC TROUGH...EAST-SOUTHEAST LOW-LEVEL WINDS AND
LINGERING MOISTURE WITH TEMPS NO LOWER THAN -3C MAY RESULT IN
DZ/FZDZ OVER CNTRL CWA INTO THE KEWEENAW THU NIGHT INTO FRI MORNING
DUE TO UPSLOPE LIFT ACCORDING TO THE GFS. ECMWF IS QUICKER IN
BRINGING DEEPER MOISTURE IN THOUGH. A BIT EARLY TO INCLUDE LOW
CHANCE FZDZ. WILL JUST KEEP WITH SNOW CHANCE ATTM.
ATTN FOR FRI AND INTO SAT IS ON SHORTWAVE TROUGH THAT IS STILL
SOUTHWEST OF THE ALEUTIAN ISLANDS OVER THE NORTHERN PACIFIC OCEAN
THIS AFTN. THIS SHORTWAVE TROUGH OR AT LEAST A PIECE OF IT SHOULD
REACH SOUTHERN CALIFORNIA ON THU AND RIDE ACROSS THE SOUTHERN PLAINS
INTO FRI. SFC LOW TIED TO THIS TROUGH DEVELOPS LEE OF ROCKIES ON THU
AND REACHES VCNTY OF WICHITA KS BY FRI MORNING. SHORTWAVE TROUGH AND
THE SFC LOW WILL THEN TRACK ACROSS MISSISSIPPI RIVER VALLEY BY FRI
EVENING AND REACH VCNTY OF UPPER GREAT LAKES ON SAT. DISAGREEMENT ON
TIMING WITH MAIN SFC LOW AND WHEN MOST PRECIP WOULD AFFECT UPR
MICHIGAN. GFS IS SLOWER IN THIS REGARD KEEPING LOW OVER UPPER GREAT
LAKES THROUGH WEEKEND WHILE ECMWF AND GEM-NH AND WPC HAND DRAWN
PROGS SHOW MAIN LOW INTO QUEBEC. CONSENSUS GIVES CHANCE POPS FRI
INTO SAT WITH ENOUGH COOLING BY LATE WEEKEND FOR NORTH-NORTHWEST
FLOW LAKE EFFECT SOME OF WHICH MAY BE ENHANCED AS ADDITIONAL WAVES
MOVE THROUGH IN THE LARGER SCALE TROUGHING. PTYPE WILL BE FORECAST
ISSUE FRI INTO FRI NIGHT...ESPECIALLY CENTRAL AND EAST CWA. BEST
CHANCE FOR PTYPE TO STAY MAINLY SNOW WOULD BE WEST AND ACROSS
KEWEENAW. ECMWF AND GEM NOT AS WEST WITH WARM AIR COMPARED TO GFS.
KEPT IT SIMPLE AND CARRIED MIX OF RAIN/SNOW SOUTH AND EAST THEN
SWITCHED BACK TO ONLY SNOW BY SAT. GULF IS OPEN AHEAD OF THE SFC LOW
BUT MUCH HIGHER PWATS TIED UP WITH ANOTHER SYSTEM LIFTING UP THE
EAST COAST AT THE SAME TIME SHOULD LIMIT HEAVY PRECIP POTENTIAL WITH
THIS SYSTEM BUT MODERATE SNOW AMOUNTS SPREAD OUT OVER A LONGER
DURATION MAY STILL OCCUR...ESPECIALLY WEST AND NORTH CENTRAL.
BEYOND DAY 7 INTO THE SECOND WEEK OF 2016...SIGNALS FM OPERATIONAL
MODELS AND LONGER RANGE MODEL CFS INDICATE POTENTIAL FOR COLDEST AIR
OF THE SEASON OVER MUCH OF CNTRL CONUS INTO THE GREAT LAKES WITH H85
TEMPS FORECAST TO DROP WELL BLO -20C. THOUGH NOT ATYPICAL AT ALL FOR
JANUARY WOULD CERTAINLY BE SHARP CONTRAST TO THE RATHER MILD WINTER
EXPERIENCED THUS FAR. ALSO WITH THE WIDE OPEN WATERS OF LK SUPERIOR
MORE LIKELY THAN NOT WOULD SEE AN ACTIVE LAKE EFFECT SNOW PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1253 PM EST SUN JAN 3 2016
LAKE EFFECT SNOW SHOWERS HAVE GENERALLY MOVED AWAY FROM ALL OF THE
TERMINALS THIS AFTERNOON. THIS HAS LED TO MVFR OR VFR CONDITIONS AT
ALL SITES. HOWEVER...ANOTHER DISBURBANCE OVER ONTARIO WILL MOVE
ACROSS THE UPPER GREAT LAKES THIS EVNEING ALLOWING FOR THE LES BANDS
TO MOVE BACK INTO THE TERMINALS LATE THIS AFTERNOON INTO TONIGHT.
CONDITIONS WILL LIKELY DROP TO IFR AT SAW AND POSSIBLY IWD UNDER N-
NW FLOW...WHILE CMX WILL LIKELY STAY MVFR AND POSSIBLY DROP TO IFR
BRIEFLY UNDER THE HEAVIER BANDS. LES ENDS ON MONDAY MORNING
LEADING TO ALL SITES BECOMING VFR BY LUNCH TIME ON MONDAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 534 AM EST SUN JAN 3 2016
NRLY GALES WILL DIMINISH EARLY TODAY BUT WINDS TO 30 KNOTS WILL
PERSIST INTO TONIGHT. WINDS WILL DIMINISH BLO 20 KNOT MON MORNING
BUT WILL INCREASE LATE WITH ANOTHER PERIOD OF SW GALES EXPECTED LATE
MON NIGHT THROUGH TUE AS HIGH PRES SLIDES EAST OF THE WRN LAKES AND
TROUGH DEVELOPS OVER THE PLAINS. WINDS WILL DIMINISH TUE NIGHT AND
REMAIN BLO 25 KNOT FROM WED THROUGH THU.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST MONDAY FOR MIZ005-006.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...MRD
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
100 PM EST SUN JAN 3 2016
.UPDATE...
ISSUED AT 1036 AM EST SUN JAN 3 2016
LES SEEMS TO BE BECOMING A LITTLE MORE DISORGANIZED THIS MORNING
/ALTHOUGH STILL LOCALLY HEAVY/ AS THE PBL WINDS BACK SLIGHTLY AND
INVERSION CRASHES BEHIND THE SHORT WAVE EARLIER THIS MORNING. WITH
WINDS BEING 330-340...EXPECT THE BEST SNOW TO REMAIN OVER WESTERN AND
CENTRAL ALGER COUNTY AND PERHAPS INTO NORTHWEST SCHOOLCRAFT NEAR
STEUBEN WHERE A LOCALIZED 3 TO 5 INCHES ARE POSSIBLE TODAY. AS
SUCH...WILL KEEP ALL ADVISORIES AS IS. AS THE NEXT SHORT WAVE OVER
ONTARIO MOVES ACROSS TONIGHT...EXPECT THE PBL FLOW TO VEER TO N-NE AS
THE INVERTED SFC TROUGH PASSES SOUTH...WHILE THE INVERSION RAISES
RATHER SIGNIFICANTLY. THIS SHOULD ALLOW FOR A BURST OF HEAVIER SNOW
TO MOVE INTO MARQUETTE COUNTY THIS EVENING INTO THE OVERNIGHT HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 526 AM EST SUN JAN 3 2016
WV IMAGERY AND RAP ANALYSIS INDICATED NNW MID/UPPER LEVEL FROM CNTRL
CANADA THROUGH THE WRN GREAT LAKES DOWNSTREAM FROM A MID/UPPER LEVEL
RIDGE FROM THE CNTRL ROCKIES INTO ALBERTA. ONE WEAK SHORTWAVE TROUGH
THAT BROUGHT A COLD FRONT THROUGH UPPER MI WAS SLIDING TO THE SE OF
THE AREA WHILE ANOTHER UPSTREAM SHRTWV WAS LOCATED OVER NE MANITOBA.
CAA IN THE WAKE OF THE FRONT DROPPING 850 MB TEMPS TO AROUND -15C
HAS ALONG WITH INCREASING NNW WINDS HAS BROUGHT AN INCREASE IN LES
INTO N CNTRL UPPER MI WITH A FEW MODERATE TO HEAVY BANDS.
HOWEVER...THE WINDS HAVE SHIFTED ENOUGH TO LIMIT THE
ORGANIZATION/INTENSITY OF THE BAND AND RESIDENCE TIME IN ANY ONE
LOCATION. SO...ACCUMULATIONS OVERNIGHT HAVE BEEN LIGHT.
TODAY...THE MODELS WERE IN GOOD AGREEMENT THAT LOW LEVEL WINDS WILL
BACK IN ADVANCE OF THE SHRTWV MOVING SSE THROUGH NW ONTARIO. THIS
WILL SHIFT THE BEST LOW LEVEL CONV FROM ERN MARQUETTE COUNTY TOWARD
MUNISING THIS AFTERNOON. ALTHOUGH UPSTREAM MOISTURE IS
FAVORABLE...INVERSION HEIGHTS NEAR 5K-6K FT WILL KEEP THE LES IN
CHECK. SNOWFALL AMOUNTS IN THE 2 TO 4 INCH RANGE ARE STILL EXPECTED
BUT WITH THE HIGHEST TOTALS OVER WRN ALGER COUNTY. SNOW SHOWERS WILL
ALSO BE LIKELY ALONG THE REST OF THE LAKE SUPERIOR SHORE FAVORED BY
NNW FLOW BUT WITH LOWER INVERSION HEIGHTS AND/OR A SHORTER FETCH
ACCUMULATIONS OF ONLY AN INCH OR TWO ARE EXPECTED.
TONIGHT...AS THE SHRTWV MOVES IN FROM LATE AFTERNOON INTO THIS
EVENING WITH 700 MB TEMPS DROPPING TO NEAR -24C...LES WILL INCREASE
AS INVERSION HEIGHTS CLIMB TO 8K-10K FT WITH LAKE INDUCED CAPE
VALUES TO 500 J/KG. WITH THE DGZ IN MID PORTION OF THE CONVECTIVE
LAYER...SLR VALUES SHOULD ALSO EXCEED 20/1. SNOWFALL RATES AOA 1
INCH/HOUR ARE EXPECTED AS THE AREA OF STRONGEST LOW LEVEL CONV
SHIFTS BACK TO THE WEST INTO MARQUETTE COUNTY AS WINDS VEER FROM NNW
TO NNE. EVEN THOUGH THE MOST FAVORABLE CONDITIONS ONLY LAST A FEW
HOURS...ADDITIONAL ACCUMULATIONS IN THE 2 TO 5 INCH RANGE ARE
LIKELY. ACCUMULATIONS OF 1 TO 3 INCHES WILL ALSO BE POSSIBLE OVER
THE REST OF NRN UPPER MI. THE SHRTWV WILL ALSO BRING INLAND
LOCATIONS SOME LIGHT SNOW AMOUNTS OF AN INCH OR LESS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 351 AM EST SUN JAN 3 2016
AT 12Z MON...SIGNIFICANT LAKE EFFECT/ENHANCED SNOW FALLING SUN NIGHT
WILL DEFINITELY BE ON THE DOWNTURN. NNE-NE LOW LEVEL WINDS AND 850MB
TEMPS WILL BE AROUND -17C AT 12Z...SO IT WILL BE SNOWING ACROSS MUCH
OF THE CWA (BEST OVER NCENTRAL UPPER MI)...BUT INTENSITIES WILL BE
KEPT IN CHECK BY FALLING INVERSIONS AND DRIER AIR ASSOCIATED WITH A
1030MB RIDGE OVER NORTHWESTERN LAKE SUPERIOR. THE RIDGE SHIFTS
COMPLETELY THROUGH THE AREA BY 18Z MON...WITH WITH SW WINDS AND
RAPIDLY WARMING 850MB TEMPS BEHIND THE RIDGE LEADING TO A DRY
FORECAST BY MID AFTERNOON MON.
A SHORTWAVE MOVING ACROSS HUDSON BAY WILL DROP A SFC TROUGH/COLD
FRONT INTO THE CWA TUE NIGHT. THE TROUGH/FRONT STALLS OVER THE CWA
INTO LATE WEEK AS A SYSTEM BEGINS TO MOVE INTO THE REGION FROM THE
SW. COULD SOME LIGHT SNOW OVER PORTIONS OF THE AREA WED AND THU.
WILL HAVE TO CONTINUE TO WATCH WHERE MODELS HAVE THE FRONT HANGING
UP TO DETERMINE WHICH AREAS WILL SEE SNOW.
MODELS SHOW A BROAD LOW MOVING FROM WRN KS AT 00Z FRI TO THE
VICINITY OF LAKE MICHIGAN BY 12Z SAT. AFTER THAT...MODELS DIFFER ON
PROGRESSION OF THE LOW THE 00Z/03 GFS KEEPS THE LOW OVER THE UPPER
GREAT LAKES INTO THE MIDDLE OF NEXT WEEK...WHILE THE ECMWF SHIFTS
THE LOW TO QUEBEC BY SUN AFTERNOON. ALSO...MODELS ARE HAVING RUN TO
RUN DISCONTINUITIES. AHEAD OF THE SYSTEM...PRECIP OVERSPREADS THE
REGION AS WARM AIR PUMPS INTO THE AREA...MAKING FOR A MIXED PRECIP
SCENARIO IF CURRENT RUNS VERIFY. COLD AIR ON THE BACK SIDE OF THE
SYSTEM WILL TURN ALL PRECIP BACK TO SNOW. OF COURSE...THERMAL FIELDS
ARE UNCERTAIN...SO WILL HAVE TO KEEP AN EYE ON THIS SYSTEM AS
MODERATE SNOWFALL AMOUNTS ARE POSSIBLE...ESPECIALLY ON THE BACK SIDE
OF THE SYSTEM AT THIS POINT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1253 PM EST SUN JAN 3 2016
LAKE EFFECT SNOW SHOWERS HAVE GENERALLY MOVED AWAY FROM ALL OF THE
TERMINALS THIS AFTERNOON. THIS HAS LED TO MVFR OR VFR CONDITIONS AT
ALL SITES. HOWEVER...ANOTHER DISBURBANCE OVER ONTARIO WILL MOVE
ACROSS THE UPPER GREAT LAKES THIS EVNEING ALLOWING FOR THE LES BANDS
TO MOVE BACK INTO THE TERMINALS LATE THIS AFTERNOON INTO TONIGHT.
CONDITIONS WILL LIKELY DROP TO IFR AT SAW AND POSSIBLY IWD UNDER N-
NW FLOW...WHILE CMX WILL LIKELY STAY MVFR AND POSSIBLY DROP TO IFR
BRIEFLY UNDER THE HEAVIER BANDS. LES ENDS ON MONDAY MORNING
LEADING TO ALL SITES BECOMING VFR BY LUNCH TIME ON MONDAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 534 AM EST SUN JAN 3 2016
NRLY GALES WILL DIMINISH EARLY TODAY BUT WINDS TO 30 KNOTS WILL
PERSIST INTO TONIGHT. WINDS WILL DIMINISH BLO 20 KNOT MON MORNING
BUT WILL INCREASE LATE WITH ANOTHER PERIOD OF SW GALES EXPECTED LATE
MON NIGHT THROUGH TUE AS HIGH PRES SLIDES EAST OF THE WRN LAKES AND
TROUGH DEVELOPS OVER THE PLAINS. WINDS WILL DIMINISH TUE NIGHT AND
REMAIN BLO 25 KNOT FROM WED THROUGH THU.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST MONDAY FOR MIZ005-006.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...MRD
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1037 AM EST SUN JAN 3 2016
.UPDATE...
ISSUED AT 1036 AM EST SUN JAN 3 2016
LES SEEMS TO BE BECOMING A LITTLE MORE DISORGANIZED THIS MORNING
/ALTHOUGH STILL LOCALLY HEAVY/ AS THE PBL WINDS BACK SLIGHTLY AND
INVERSION CRASHES BEHIND THE SHORT WAVE EARLIER THIS MORNING. WITH
WINDS BEING 330-340...EXPECT THE BEST SNOW TO REMAIN OVER WESTERN AND
CENTRAL ALGER COUNTY AND PERHAPS INTO NORTHWEST SCHOOLCRAFT NEAR
STEUBEN WHERE A LOCALIZED 3 TO 5 INCHES ARE POSSIBLE TODAY. AS
SUCH...WILL KEEP ALL ADVISORIES AS IS. AS THE NEXT SHORT WAVE OVER
ONTARIO MOVES ACROSS TONIGHT...EXPECT THE PBL FLOW TO VEER TO N-NE AS
THE INVERTED SFC TROUGH PASSES SOUTH...WHILE THE INVERSION RAISES
RATHER SIGNIFICANTLY. THIS SHOULD ALLOW FOR A BURST OF HEAVIER SNOW
TO MOVE INTO MARQUETTE COUNTY THIS EVENING INTO THE OVERNIGHT HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 526 AM EST SUN JAN 3 2016
WV IMAGERY AND RAP ANALYSIS INDICATED NNW MID/UPPER LEVEL FROM CNTRL
CANADA THROUGH THE WRN GREAT LAKES DOWNSTREAM FROM A MID/UPPER LEVEL
RIDGE FROM THE CNTRL ROCKIES INTO ALBERTA. ONE WEAK SHORTWAVE TROUGH
THAT BROUGHT A COLD FRONT THROUGH UPPER MI WAS SLIDING TO THE SE OF
THE AREA WHILE ANOTHER UPSTREAM SHRTWV WAS LOCATED OVER NE MANITOBA.
CAA IN THE WAKE OF THE FRONT DROPPING 850 MB TEMPS TO AROUND -15C
HAS ALONG WITH INCREASING NNW WINDS HAS BROUGHT AN INCREASE IN LES
INTO N CNTRL UPPER MI WITH A FEW MODERATE TO HEAVY BANDS.
HOWEVER...THE WINDS HAVE SHIFTED ENOUGH TO LIMIT THE
ORGANIZATION/INTENSITY OF THE BAND AND RESIDENCE TIME IN ANY ONE
LOCATION. SO...ACCUMULATIONS OVERNIGHT HAVE BEEN LIGHT.
TODAY...THE MODELS WERE IN GOOD AGREEMENT THAT LOW LEVEL WINDS WILL
BACK IN ADVANCE OF THE SHRTWV MOVING SSE THROUGH NW ONTARIO. THIS
WILL SHIFT THE BEST LOW LEVEL CONV FROM ERN MARQUETTE COUNTY TOWARD
MUNISING THIS AFTERNOON. ALTHOUGH UPSTREAM MOISTURE IS
FAVORABLE...INVERSION HEIGHTS NEAR 5K-6K FT WILL KEEP THE LES IN
CHECK. SNOWFALL AMOUNTS IN THE 2 TO 4 INCH RANGE ARE STILL EXPECTED
BUT WITH THE HIGHEST TOTALS OVER WRN ALGER COUNTY. SNOW SHOWERS WILL
ALSO BE LIKELY ALONG THE REST OF THE LAKE SUPERIOR SHORE FAVORED BY
NNW FLOW BUT WITH LOWER INVERSION HEIGHTS AND/OR A SHORTER FETCH
ACCUMULATIONS OF ONLY AN INCH OR TWO ARE EXPECTED.
TONIGHT...AS THE SHRTWV MOVES IN FROM LATE AFTERNOON INTO THIS
EVENING WITH 700 MB TEMPS DROPPING TO NEAR -24C...LES WILL INCREASE
AS INVERSION HEIGHTS CLIMB TO 8K-10K FT WITH LAKE INDUCED CAPE
VALUES TO 500 J/KG. WITH THE DGZ IN MID PORTION OF THE CONVECTIVE
LAYER...SLR VALUES SHOULD ALSO EXCEED 20/1. SNOWFALL RATES AOA 1
INCH/HOUR ARE EXPECTED AS THE AREA OF STRONGEST LOW LEVEL CONV
SHIFTS BACK TO THE WEST INTO MARQUETTE COUNTY AS WINDS VEER FROM NNW
TO NNE. EVEN THOUGH THE MOST FAVORABLE CONDITIONS ONLY LAST A FEW
HOURS...ADDITIONAL ACCUMULATIONS IN THE 2 TO 5 INCH RANGE ARE
LIKELY. ACCUMULATIONS OF 1 TO 3 INCHES WILL ALSO BE POSSIBLE OVER
THE REST OF NRN UPPER MI. THE SHRTWV WILL ALSO BRING INLAND
LOCATIONS SOME LIGHT SNOW AMOUNTS OF AN INCH OR LESS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 351 AM EST SUN JAN 3 2016
AT 12Z MON...SIGNIFICANT LAKE EFFECT/ENHANCED SNOW FALLING SUN NIGHT
WILL DEFINITELY BE ON THE DOWNTURN. NNE-NE LOW LEVEL WINDS AND 850MB
TEMPS WILL BE AROUND -17C AT 12Z...SO IT WILL BE SNOWING ACROSS MUCH
OF THE CWA (BEST OVER NCENTRAL UPPER MI)...BUT INTENSITIES WILL BE
KEPT IN CHECK BY FALLING INVERSIONS AND DRIER AIR ASSOCIATED WITH A
1030MB RIDGE OVER NORTHWESTERN LAKE SUPERIOR. THE RIDGE SHIFTS
COMPLETELY THROUGH THE AREA BY 18Z MON...WITH WITH SW WINDS AND
RAPIDLY WARMING 850MB TEMPS BEHIND THE RIDGE LEADING TO A DRY
FORECAST BY MID AFTERNOON MON.
A SHORTWAVE MOVING ACROSS HUDSON BAY WILL DROP A SFC TROUGH/COLD
FRONT INTO THE CWA TUE NIGHT. THE TROUGH/FRONT STALLS OVER THE CWA
INTO LATE WEEK AS A SYSTEM BEGINS TO MOVE INTO THE REGION FROM THE
SW. COULD SOME LIGHT SNOW OVER PORTIONS OF THE AREA WED AND THU.
WILL HAVE TO CONTINUE TO WATCH WHERE MODELS HAVE THE FRONT HANGING
UP TO DETERMINE WHICH AREAS WILL SEE SNOW.
MODELS SHOW A BROAD LOW MOVING FROM WRN KS AT 00Z FRI TO THE
VICINITY OF LAKE MICHIGAN BY 12Z SAT. AFTER THAT...MODELS DIFFER ON
PROGRESSION OF THE LOW THE 00Z/03 GFS KEEPS THE LOW OVER THE UPPER
GREAT LAKES INTO THE MIDDLE OF NEXT WEEK...WHILE THE ECMWF SHIFTS
THE LOW TO QUEBEC BY SUN AFTERNOON. ALSO...MODELS ARE HAVING RUN TO
RUN DISCONTINUITIES. AHEAD OF THE SYSTEM...PRECIP OVERSPREADS THE
REGION AS WARM AIR PUMPS INTO THE AREA...MAKING FOR A MIXED PRECIP
SCENARIO IF CURRENT RUNS VERIFY. COLD AIR ON THE BACK SIDE OF THE
SYSTEM WILL TURN ALL PRECIP BACK TO SNOW. OF COURSE...THERMAL FIELDS
ARE UNCERTAIN...SO WILL HAVE TO KEEP AN EYE ON THIS SYSTEM AS
MODERATE SNOWFALL AMOUNTS ARE POSSIBLE...ESPECIALLY ON THE BACK SIDE
OF THE SYSTEM AT THIS POINT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 648 AM EST SUN JAN 3 2016
EXPECT NMRS LK EFFECT -SHSN TO IMPACT THE TAF SITES THIS FCST PERIOD
AS A NNW WIND ADVECTS COLDER AIR OVER THE RELATIVELY WARM WATERS OF
LAKE SUPERIOR. THE BEST CHANCE FOR THE LOWER IFR VSBYS WL BE AT
SAW...WHICH WILL BE CLOSE TO THE WRN EDGE OF HEAVIER BANDS OF LES.
ALTHOUGH THE BANDS MAY SHIFT TO THE E FOR A TIME THIS AFTN...THE
ARRIVAL OF ANOTHER DISTURBANCE AND LOW PRES TROUGH/AXIS OF FOCUSED
LOW LEVEL CONVERGECNE WILL LIKELY BRING SOME IFR VSBYS TO ALL THE
SITES AT LEAST FOR A PERIOD LATE TODAY AND THIS EVENING. ONCE
AGAIN...THE SAW SITE APPEARS MOST LIKELY TO BE IMPACTED BY THE
LOWEST IFR VSBY. THE LES SHOULD DIMINISH LATE TONIGHT WITH VSBY
IMPROVING TO MVFR OR VFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 534 AM EST SUN JAN 3 2016
NRLY GALES WILL DIMINISH EARLY TODAY BUT WINDS TO 30 KNOTS WILL
PERSIST INTO TONIGHT. WINDS WILL DIMINISH BLO 20 KNOT MON MORNING
BUT WILL INCREASE LATE WITH ANOTHER PERIOD OF SW GALES EXPECTED LATE
MON NIGHT THROUGH TUE AS HIGH PRES SLIDES EAST OF THE WRN LAKES AND
TROUGH DEVELOPS OVER THE PLAINS. WINDS WILL DIMINISH TUE NIGHT AND
REMAIN BLO 25 KNOT FROM WED THROUGH THU.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST MONDAY FOR MIZ005-006.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...MRD
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
649 AM EST SUN JAN 3 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 526 AM EST SUN JAN 3 2016
WV IMAGERY AND RAP ANALYSIS INDICATED NNW MID/UPPER LEVEL FROM CNTRL
CANADA THROUGH THE WRN GREAT LAKES DOWNSTREAM FROM A MID/UPPER LEVEL
RIDGE FROM THE CNTRL ROCKIES INTO ALBERTA. ONE WEAK SHORTWAVE TROUGH
THAT BROUGHT A COLD FRONT THROUGH UPPER MI WAS SLIDING TO THE SE OF
THE AREA WHILE ANOTHER UPSTREAM SHRTWV WAS LOCATED OVER NE MANITOBA.
CAA IN THE WAKE OF THE FRONT DROPPING 850 MB TEMPS TO AROUND -15C
HAS ALONG WITH INCREASING NNW WINDS HAS BROUGHT AN INCREASE IN LES
INTO N CNTRL UPPER MI WITH A FEW MODERATE TO HEAVY BANDS.
HOWEVER...THE WINDS HAVE SHIFTED ENOUGH TO LIMIT THE
ORGANIZATION/INTENSITY OF THE BAND AND RESIDENCE TIME IN ANY ONE
LOCATION. SO...ACCUMULATIONS OVERNIGHT HAVE BEEN LIGHT.
TODAY...THE MODELS WERE IN GOOD AGREEMENT THAT LOW LEVEL WINDS WILL
BACK IN ADVANCE OF THE SHRTWV MOVING SSE THROUGH NW ONTARIO. THIS
WILL SHIFT THE BEST LOW LEVEL CONV FROM ERN MARQUETTE COUNTY TOWARD
MUNISING THIS AFTERNOON. ALTHOUGH UPSTREAM MOISTURE IS
FAVORABLE...INVERSION HEIGHTS NEAR 5K-6K FT WILL KEEP THE LES IN
CHECK. SNOWFALL AMOUNTS IN THE 2 TO 4 INCH RANGE ARE STILL EXPECTED
BUT WITH THE HIGHEST TOTALS OVER WRN ALGER COUNTY. SNOW SHOWERS WILL
ALSO BE LIKELY ALONG THE REST OF THE LAKE SUPERIOR SHORE FAVORED BY
NNW FLOW BUT WITH LOWER INVERSION HEIGHTS AND/OR A SHORTER FETCH
ACCUMULATIONS OF ONLY AN INCH OR TWO ARE EXPECTED.
TONIGHT...AS THE SHRTWV MOVES IN FROM LATE AFTERNOON INTO THIS
EVENING WITH 700 MB TEMPS DROPPING TO NEAR -24C...LES WILL INCREASE
AS INVERSION HEIGHTS CLIMB TO 8K-10K FT WITH LAKE INDUCED CAPE
VALUES TO 500 J/KG. WITH THE DGZ IN MID PORTION OF THE CONVECTIVE
LAYER...SLR VALUES SHOULD ALSO EXCEED 20/1. SNOWFALL RATES AOA 1
INCH/HOUR ARE EXPECTED AS THE AREA OF STRONGEST LOW LEVEL CONV
SHIFTS BACK TO THE WEST INTO MARQUETTE COUNTY AS WINDS VEER FROM NNW
TO NNE. EVEN THOUGH THE MOST FAVORABLE CONDITIONS ONLY LAST A FEW
HOURS...ADDITIONAL ACCUMULATIONS IN THE 2 TO 5 INCH RANGE ARE
LIKELY. ACCUMULATIONS OF 1 TO 3 INCHES WILL ALSO BE POSSIBLE OVER
THE REST OF NRN UPPER MI. THE SHRTWV WILL ALSO BRING INLAND
LOCATIONS SOME LIGHT SNOW AMOUNTS OF AN INCH OR LESS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 351 AM EST SUN JAN 3 2016
AT 12Z MON...SIGNIFICANT LAKE EFFECT/ENHANCED SNOW FALLING SUN NIGHT
WILL DEFINITELY BE ON THE DOWNTURN. NNE-NE LOW LEVEL WINDS AND 850MB
TEMPS WILL BE AROUND -17C AT 12Z...SO IT WILL BE SNOWING ACROSS MUCH
OF THE CWA (BEST OVER NCENTRAL UPPER MI)...BUT INTENSITIES WILL BE
KEPT IN CHECK BY FALLING INVERSIONS AND DRIER AIR ASSOCIATED WITH A
1030MB RIDGE OVER NORTHWESTERN LAKE SUPERIOR. THE RIDGE SHIFTS
COMPLETELY THROUGH THE AREA BY 18Z MON...WITH WITH SW WINDS AND
RAPIDLY WARMING 850MB TEMPS BEHIND THE RIDGE LEADING TO A DRY
FORECAST BY MID AFTERNOON MON.
A SHORTWAVE MOVING ACROSS HUDSON BAY WILL DROP A SFC TROUGH/COLD
FRONT INTO THE CWA TUE NIGHT. THE TROUGH/FRONT STALLS OVER THE CWA
INTO LATE WEEK AS A SYSTEM BEGINS TO MOVE INTO THE REGION FROM THE
SW. COULD SOME LIGHT SNOW OVER PORTIONS OF THE AREA WED AND THU.
WILL HAVE TO CONTINUE TO WATCH WHERE MODELS HAVE THE FRONT HANGING
UP TO DETERMINE WHICH AREAS WILL SEE SNOW.
MODELS SHOW A BROAD LOW MOVING FROM WRN KS AT 00Z FRI TO THE
VICINITY OF LAKE MICHIGAN BY 12Z SAT. AFTER THAT...MODELS DIFFER ON
PROGRESSION OF THE LOW THE 00Z/03 GFS KEEPS THE LOW OVER THE UPPER
GREAT LAKES INTO THE MIDDLE OF NEXT WEEK...WHILE THE ECMWF SHIFTS
THE LOW TO QUEBEC BY SUN AFTERNOON. ALSO...MODELS ARE HAVING RUN TO
RUN DISCONTINUITIES. AHEAD OF THE SYSTEM...PRECIP OVERSPREADS THE
REGION AS WARM AIR PUMPS INTO THE AREA...MAKING FOR A MIXED PRECIP
SCENARIO IF CURRENT RUNS VERIFY. COLD AIR ON THE BACK SIDE OF THE
SYSTEM WILL TURN ALL PRECIP BACK TO SNOW. OF COURSE...THERMAL FIELDS
ARE UNCERTAIN...SO WILL HAVE TO KEEP AN EYE ON THIS SYSTEM AS
MODERATE SNOWFALL AMOUNTS ARE POSSIBLE...ESPECIALLY ON THE BACK SIDE
OF THE SYSTEM AT THIS POINT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 648 AM EST SUN JAN 3 2016
EXPECT NMRS LK EFFECT -SHSN TO IMPACT THE TAF SITES THIS FCST PERIOD
AS A NNW WIND ADVECTS COLDER AIR OVER THE RELATIVELY WARM WATERS OF
LAKE SUPERIOR. THE BEST CHANCE FOR THE LOWER IFR VSBYS WL BE AT
SAW...WHICH WILL BE CLOSE TO THE WRN EDGE OF HEAVIER BANDS OF LES.
ALTHOUGH THE BANDS MAY SHIFT TO THE E FOR A TIME THIS AFTN...THE
ARRIVAL OF ANOTHER DISTURBANCE AND LOW PRES TROUGH/AXIS OF FOCUSED
LOW LEVEL CONVERGECNE WILL LIKELY BRING SOME IFR VSBYS TO ALL THE
SITES AT LEAST FOR A PERIOD LATE TODAY AND THIS EVENING. ONCE
AGAIN...THE SAW SITE APPEARS MOST LIKELY TO BE IMPACTED BY THE
LOWEST IFR VSBY. THE LES SHOULD DIMINISH LATE TONIGHT WITH VSBY
IMPROVING TO MVFR OR VFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 534 AM EST SUN JAN 3 2016
NRLY GALES WILL DIMINISH EARLY TODAY BUT WINDS TO 30 KNOTS WILL
PERSIST INTO TONIGHT. WINDS WILL DIMINISH BLO 20 KNOT MON MORNING
BUT WILL INCREASE LATE WITH ANOTHER PERIOD OF SW GALES EXPECTED LATE
MON NIGHT THROUGH TUE AS HIGH PRES SLIDES EAST OF THE WRN LAKES AND
TROUGH DEVELOPS OVER THE PLAINS. WINDS WILL DIMINISH TUE NIGHT AND
REMAIN BLO 25 KNOT FROM WED THROUGH THU.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST MONDAY FOR MIZ005-006.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 AM EST THIS MORNING FOR LSZ249-250-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
535 AM EST SUN JAN 3 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 526 AM EST SUN JAN 3 2016
WV IMAGERY AND RAP ANALYSIS INDICATED NNW MID/UPPER LEVEL FROM CNTRL
CANADA THROUGH THE WRN GREAT LAKES DOWNSTREAM FROM A MID/UPPER LEVEL
RIDGE FROM THE CNTRL ROCKIES INTO ALBERTA. ONE WEAK SHORTWAVE TROUGH
THAT BROUGHT A COLD FRONT THROUGH UPPER MI WAS SLIDING TO THE SE OF
THE AREA WHILE ANOTHER UPSTREAM SHRTWV WAS LOCATED OVER NE MANITOBA.
CAA IN THE WAKE OF THE FRONT DROPPING 850 MB TEMPS TO AROUND -15C
HAS ALONG WITH INCREASING NNW WINDS HAS BROUGHT AN INCREASE IN LES
INTO N CNTRL UPPER MI WITH A FEW MODERATE TO HEAVY BANDS.
HOWEVER...THE WINDS HAVE SHIFTED ENOUGH TO LIMIT THE
ORGANIZATION/INTENSITY OF THE BAND AND RESIDENCE TIME IN ANY ONE
LOCATION. SO...ACCUMULATIONS OVERNIGHT HAVE BEEN LIGHT.
TODAY...THE MODELS WERE IN GOOD AGREEMENT THAT LOW LEVEL WINDS WILL
BACK IN ADVANCE OF THE SHRTWV MOVING SSE THROUGH NW ONTARIO. THIS
WILL SHIFT THE BEST LOW LEVEL CONV FROM ERN MARQUETTE COUNTY TOWARD
MUNISING THIS AFTERNOON. ALTHOUGH UPSTREAM MOISTURE IS
FAVORABLE...INVERSION HEIGHTS NEAR 5K-6K FT WILL KEEP THE LES IN
CHECK. SNOWFALL AMOUNTS IN THE 2 TO 4 INCH RANGE ARE STILL EXPECTED
BUT WITH THE HIGHEST TOTALS OVER WRN ALGER COUNTY. SNOW SHOWERS WILL
ALSO BE LIKELY ALONG THE REST OF THE LAKE SUPERIOR SHORE FAVORED BY
NNW FLOW BUT WITH LOWER INVERSION HEIGHTS AND/OR A SHORTER FETCH
ACCUMULATIONS OF ONLY AN INCH OR TWO ARE EXPECTED.
TONIGHT...AS THE SHRTWV MOVES IN FROM LATE AFTERNOON INTO THIS
EVENING WITH 700 MB TEMPS DROPPING TO NEAR -24C...LES WILL INCREASE
AS INVERSION HEIGHTS CLIMB TO 8K-10K FT WITH LAKE INDUCED CAPE
VALUES TO 500 J/KG. WITH THE DGZ IN MID PORTION OF THE CONVECTIVE
LAYER...SLR VALUES SHOULD ALSO EXCEED 20/1. SNOWFALL RATES AOA 1
INCH/HOUR ARE EXPECTED AS THE AREA OF STRONGEST LOW LEVEL CONV
SHIFTS BACK TO THE WEST INTO MARQUETTE COUNTY AS WINDS VEER FROM NNW
TO NNE. EVEN THOUGH THE MOST FAVORABLE CONDITIONS ONLY LAST A FEW
HOURS...ADDITIONAL ACCUMULATIONS IN THE 2 TO 5 INCH RANGE ARE
LIKELY. ACCUMULATIONS OF 1 TO 3 INCHES WILL ALSO BE POSSIBLE OVER
THE REST OF NRN UPPER MI. THE SHRTWV WILL ALSO BRING INLAND
LOCATIONS SOME LIGHT SNOW AMOUNTS OF AN INCH OR LESS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 351 AM EST SUN JAN 3 2016
AT 12Z MON...SIGNIFICANT LAKE EFFECT/ENHANCED SNOW FALLING SUN NIGHT
WILL DEFINITELY BE ON THE DOWNTURN. NNE-NE LOW LEVEL WINDS AND 850MB
TEMPS WILL BE AROUND -17C AT 12Z...SO IT WILL BE SNOWING ACROSS MUCH
OF THE CWA (BEST OVER NCENTRAL UPPER MI)...BUT INTENSITIES WILL BE
KEPT IN CHECK BY FALLING INVERSIONS AND DRIER AIR ASSOCIATED WITH A
1030MB RIDGE OVER NORTHWESTERN LAKE SUPERIOR. THE RIDGE SHIFTS
COMPLETELY THROUGH THE AREA BY 18Z MON...WITH WITH SW WINDS AND
RAPIDLY WARMING 850MB TEMPS BEHIND THE RIDGE LEADING TO A DRY
FORECAST BY MID AFTERNOON MON.
A SHORTWAVE MOVING ACROSS HUDSON BAY WILL DROP A SFC TROUGH/COLD
FRONT INTO THE CWA TUE NIGHT. THE TROUGH/FRONT STALLS OVER THE CWA
INTO LATE WEEK AS A SYSTEM BEGINS TO MOVE INTO THE REGION FROM THE
SW. COULD SOME LIGHT SNOW OVER PORTIONS OF THE AREA WED AND THU.
WILL HAVE TO CONTINUE TO WATCH WHERE MODELS HAVE THE FRONT HANGING
UP TO DETERMINE WHICH AREAS WILL SEE SNOW.
MODELS SHOW A BROAD LOW MOVING FROM WRN KS AT 00Z FRI TO THE
VICINITY OF LAKE MICHIGAN BY 12Z SAT. AFTER THAT...MODELS DIFFER ON
PROGRESSION OF THE LOW THE 00Z/03 GFS KEEPS THE LOW OVER THE UPPER
GREAT LAKES INTO THE MIDDLE OF NEXT WEEK...WHILE THE ECMWF SHIFTS
THE LOW TO QUEBEC BY SUN AFTERNOON. ALSO...MODELS ARE HAVING RUN TO
RUN DISCONTINUITIES. AHEAD OF THE SYSTEM...PRECIP OVERSPREADS THE
REGION AS WARM AIR PUMPS INTO THE AREA...MAKING FOR A MIXED PRECIP
SCENARIO IF CURRENT RUNS VERIFY. COLD AIR ON THE BACK SIDE OF THE
SYSTEM WILL TURN ALL PRECIP BACK TO SNOW. OF COURSE...THERMAL FIELDS
ARE UNCERTAIN...SO WILL HAVE TO KEEP AN EYE ON THIS SYSTEM AS
MODERATE SNOWFALL AMOUNTS ARE POSSIBLE...ESPECIALLY ON THE BACK SIDE
OF THE SYSTEM AT THIS POINT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1243 AM EST SUN JAN 3 2016
EXPECT NMRS LK EFFECT -SHSN TO IMPACT THE TAF SITES THIS FCST PERIOD
AS A SLOWLY DIMINISHING NNW WIND ADVECTS COLDER AIR OVER THE
RELATIVELY WARM WATERS OF LK SUP. LARGER SCALE SUBSIDENCE HAS SLOWED
THE DEVELOPMENT OF THE HEAVIER SHSN...BUT AS DEEPER MSTR NOW N OF LK
SUP IN ONTARIO ARRIVES THIS MRNG...EXPECT THE SHSN COVERAGE/
INTENSITY TO INCREASE A BIT. THE BEST CHANCE FOR THE LOWER IFR VSBYS
WL BE AT SAW...WHICH WL BE CLOSE TO THE WRN EDGE OF A HEAVIER BAND
OF LES. ALTHOUGH THIS BAND MAY SHIFT TO THE E FOR A TIME THIS
AFTN...THE ARRIVAL OF ANOTHER DISTURBANCE/LO PRES TROF/AXIS OF
FOCUSED LLVL CNVGC WL LIKELY BRING SOME IFR VSBYS TO ALL THE SITES
AT LEAST FOR A PERIOD LATER TDAY/THIS EVNG. ONCE AGAIN...THE SAW
SITE APPEARS MOST LIKELY TO BE IMPACTED BY THE MOST AUSTERE LOWER
IFR CONDITIONS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 534 AM EST SUN JAN 3 2016
NRLY GALES WILL DIMINISH EARLY TODAY BUT WINDS TO 30 KNOTS WILL
PERSIST INTO TONIGHT. WINDS WILL DIMINISH BLO 20 KNOT MON MORNING
BUT WILL INCREASE LATE WITH ANOTHER PERIOD OF SW GALES EXPECTED LATE
MON NIGHT THROUGH TUE AS HIGH PRES SLIDES EAST OF THE WRN LAKES AND
TROUGH DEVELOPS OVER THE PLAINS. WINDS WILL DIMINISH TUE NIGHT AND
REMAIN BLO 25 KNOT FROM WED THROUGH THU.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST MONDAY FOR MIZ005-006.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 AM EST THIS MORNING FOR LSZ249-250-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
527 AM EST SUN JAN 3 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 526 AM EST SUN JAN 3 2016
WV IMAGERY AND RAP ANALYSIS INDICATED NNW MID/UPPER LEVEL FROM CNTRL
CANADA THROUGH THE WRN GREAT LAKES DOWNSTREAM FROM A MID/UPPER LEVEL
RIDGE FROM THE CNTRL ROCKIES INTO ALBERTA. ONE WEAK SHORTWAVE TROUGH
THAT BROUGHT A COLD FRONT THROUGH UPPER MI WAS SLIDING TO THE SE OF
THE AREA WHILE ANOTHER UPSTREAM SHRTWV WAS LOCATED OVER NE MANITOBA.
CAA IN THE WAKE OF THE FRONT DROPPING 850 MB TEMPS TO AROUND -15C
HAS ALONG WITH INCREASING NNW WINDS HAS BROUGHT AN INCREASE IN LES
INTO N CNTRL UPPER MI WITH A FEW MODERATE TO HEAVY BANDS.
HOWEVER...THE WINDS HAVE SHIFTED ENOUGH TO LIMIT THE
ORGANIZATION/INTENSITY OF THE BAND AND RESIDENCE TIME IN ANY ONE
LOCATION. SO...ACCUMULATIONS OVERNIGHT HAVE BEEN LIGHT.
TODAY...THE MODELS WERE IN GOOD AGREEMENT THAT LOW LEVEL WINDS WILL
BACK IN ADVANCE OF THE SHRTWV MOVING SSE THROUGH NW ONTARIO. THIS
WILL SHIFT THE BEST LOW LEVEL CONV FROM ERN MARQUETTE COUNTY TOWARD
MUNISING THIS AFTERNOON. ALTHOUGH UPSTREAM MOISTURE IS
FAVORABLE...INVERSION HEIGHTS NEAR 5K-6K FT WILL KEEP THE LES IN
CHECK. SNOWFALL AMOUNTS IN THE 2 TO 4 INCH RANGE ARE STILL EXPECTED
BUT WITH THE HIGHEST TOTALS OVER WRN ALGER COUNTY. SNOW SHOWERS WILL
ALSO BE LIKELY ALONG THE REST OF THE LAKE SUPERIOR SHORE FAVORED BY
NNW FLOW BUT WITH LOWER INVERSION HEIGHTS AND/OR A SHORTER FETCH
ACCUMULATIONS OF ONLY AN INCH OR TWO ARE EXPECTED.
TONIGHT...AS THE SHRTWV MOVES IN FROM LATE AFTERNOON INTO THIS
EVENING WITH 700 MB TEMPS DROPPING TO NEAR -24C...LES WILL INCREASE
AS INVERSION HEIGHTS CLIMB TO 8K-10K FT WITH LAKE INDUCED CAPE
VALUES TO 500 J/KG. WITH THE DGZ IN MID PORTION OF THE CONVECTIVE
LAYER...SLR VALUES SHOULD ALSO EXCEED 20/1. SNOWFALL RATES AOA 1
INCH/HOUR ARE EXPECTED AS THE AREA OF STRONGEST LOW LEVEL CONV
SHIFTS BACK TO THE WEST INTO MARQUETTE COUNTY AS WINDS VEER FROM NNW
TO NNE. EVEN THOUGH THE MOST FAVORABLE CONDITIONS ONLY LAST A FEW
HOURS...ADDITIONAL ACCUMULATIONS IN THE 2 TO 5 INCH RANGE ARE
LIKELY. ACCUMUATIONS OF 1 TO 3 INCHES WILL ALSO BE POSSIBLE OVER
THEREST OF NRN UPPER MI. THE SHRTWV WILL ALSO BRING INLAND LOCATIONS
SOME LIGHT SNOW AMOUNTS OF AN INCH OR LESS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 351 AM EST SUN JAN 3 2016
AT 12Z MON...SIGNIFICANT LAKE EFFECT/ENHANCED SNOW FALLING SUN NIGHT
WILL DEFINITELY BE ON THE DOWNTURN. NNE-NE LOW LEVEL WINDS AND 850MB
TEMPS WILL BE AROUND -17C AT 12Z...SO IT WILL BE SNOWING ACROSS MUCH
OF THE CWA (BEST OVER NCENTRAL UPPER MI)...BUT INTENSITIES WILL BE
KEPT IN CHECK BY FALLING INVERSIONS AND DRIER AIR ASSOCIATED WITH A
1030MB RIDGE OVER NORTHWESTERN LAKE SUPERIOR. THE RIDGE SHIFTS
COMPLETELY THROUGH THE AREA BY 18Z MON...WITH WITH SW WINDS AND
RAPIDLY WARMING 850MB TEMPS BEHIND THE RIDGE LEADING TO A DRY
FORECAST BY MID AFTERNOON MON.
A SHORTWAVE MOVING ACROSS HUDSON BAY WILL DROP A SFC TROUGH/COLD
FRONT INTO THE CWA TUE NIGHT. THE TROUGH/FRONT STALLS OVER THE CWA
INTO LATE WEEK AS A SYSTEM BEGINS TO MOVE INTO THE REGION FROM THE
SW. COULD SOME LIGHT SNOW OVER PORTIONS OF THE AREA WED AND THU.
WILL HAVE TO CONTINUE TO WATCH WHERE MODELS HAVE THE FRONT HANGING
UP TO DETERMINE WHICH AREAS WILL SEE SNOW.
MODELS SHOW A BROAD LOW MOVING FROM WRN KS AT 00Z FRI TO THE
VICINITY OF LAKE MICHIGAN BY 12Z SAT. AFTER THAT...MODELS DIFFER ON
PROGRESSION OF THE LOW THE 00Z/03 GFS KEEPS THE LOW OVER THE UPPER
GREAT LAKES INTO THE MIDDLE OF NEXT WEEK...WHILE THE ECMWF SHIFTS
THE LOW TO QUEBEC BY SUN AFTERNOON. ALSO...MODELS ARE HAVING RUN TO
RUN DISCONTINUITIES. AHEAD OF THE SYSTEM...PRECIP OVERSPREADS THE
REGION AS WARM AIR PUMPS INTO THE AREA...MAKING FOR A MIXED PRECIP
SCENARIO IF CURRENT RUNS VERIFY. COLD AIR ON THE BACK SIDE OF THE
SYSTEM WILL TURN ALL PRECIP BACK TO SNOW. OF COURSE...THERMAL FIELDS
ARE UNCERTAIN...SO WILL HAVE TO KEEP AN EYE ON THIS SYSTEM AS
MODERATE SNOWFALL AMOUNTS ARE POSSIBLE...ESPECIALLY ON THE BACK SIDE
OF THE SYSTEM AT THIS POINT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1243 AM EST SUN JAN 3 2016
EXPECT NMRS LK EFFECT -SHSN TO IMPACT THE TAF SITES THIS FCST PERIOD
AS A SLOWLY DIMINISHING NNW WIND ADVECTS COLDER AIR OVER THE
RELATIVELY WARM WATERS OF LK SUP. LARGER SCALE SUBSIDENCE HAS SLOWED
THE DEVELOPMENT OF THE HEAVIER SHSN...BUT AS DEEPER MSTR NOW N OF LK
SUP IN ONTARIO ARRIVES THIS MRNG...EXPECT THE SHSN COVERAGE/
INTENSITY TO INCREASE A BIT. THE BEST CHANCE FOR THE LOWER IFR VSBYS
WL BE AT SAW...WHICH WL BE CLOSE TO THE WRN EDGE OF A HEAVIER BAND
OF LES. ALTHOUGH THIS BAND MAY SHIFT TO THE E FOR A TIME THIS
AFTN...THE ARRIVAL OF ANOTHER DISTURBANCE/LO PRES TROF/AXIS OF
FOCUSED LLVL CNVGC WL LIKELY BRING SOME IFR VSBYS TO ALL THE SITES
AT LEAST FOR A PERIOD LATER TDAY/THIS EVNG. ONCE AGAIN...THE SAW
SITE APPEARS MOST LIKELY TO BE IMPACTED BY THE MOST AUSTERE LOWER
IFR CONDITIONS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 258 PM EST SAT JAN 2 2016
UPPER GREAT LAKES REMAINS SITUATED BTWN LARGE HIGH PRESSURE OVER THE
ROCKIES AND LOW PRESSURE IN FAR NE CANADA. THE TIGHT PRESSURE
GRADIENT WILL REMAIN INTO TONIGHT RESULTING IN GALES INTO TONIGHT.
NEXT GALE EVENT LOOKS TO BE MON NIGHT INTO TUE ACROSS CENTRAL LAKE
SUPERIOR WITH SW GALES TO 35 KNOTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST MONDAY FOR MIZ005-006.
LAKE SUPERIOR...
GALE WARNING UNTIL 7 AM EST THIS MORNING FOR LSZ249-250-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...KC
MARINE...07
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
342 PM CST SUN JAN 3 2016
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 330 PM CST SUN JAN 3 2016
THE SHORT TERM FORECAST CONCERNS ARE CLOUD COVER...HOW FAR SOUTH
AND EAST THE CLEARING LOCATED IN NW MN WILL EXTEND AS WELL AS
OVERNIGHT TEMPERATURES ASSOCIATED WITH CLOUDS OR NO CLOUDS.
SATELLITE SHOWS CLEAR SKIES OVER NW MN AND ALL OF ND AND MOST OF SD.
THIS AREA OF CLEARING IS SLOWLY MOVING SOUTHEAST AND IT IS
QUESTIONABLE AS TO HOW FAR SOUTH AND EAST IT WILL GO. MODEL
SOLUTIONS ARE SOMEWHAT MIXED. THE HRRR WANTS TO MIX OUT CLOUDS IN A
SOMEWHAT NATURAL PROGRESSION FROM NW TO SE. THE VARIOUS HOPWRF RUNS
ARE SOMEWHAT CONFLICTING TOO. IF YOU USE H875 OR H900 RH AS A PROXY
FOR WHERE CLOUDS ARE AND ARE NOT...THE GFS SHUNTS RH EAST OF THE
AREA AROUND 06Z. THE NAM IS EVEN FASTER. THE CHALLENGE IS WITH HIGH
PRESSURE WEST OF THE AREA AND DRIFTING SE TOWARD SW MN THERE IS NO
COMPELLING ARGUMENT FOR UNLOADING ENOUGH OF THE LOW LEVEL MOISTURE
TO SCATTER THE CLOUDS OUT. TO MAKE THINGS MORE CHALLENGING AREA THAT
WERE DOMINATED BY THE HIGH PRESSURE TODAY SAW VIRTUALLY NO LOSS OF
CLOUD COVER. AS A RESULT WILL SLOWLY SCATTER THE CLOUDS BETWEEN THE
I-94 CORRIDOR AND THE MN RIVER VALLEY TONIGHT. THERE MAY BE SOME
BREAK IN THE CLOUDS AS FAR SOUTH AND EAST AS THE TWIN
CITIES. SO WILL CONTINUE THAT TREND INTO MONDAY. WESTERN WI WILL
REMAIN OVERCAST. OVERNIGHT LOWS WERE ADJUSTED TO ACCOUNT FOR THE
VARYING CLOUD COVER. MORE SCATTERING OF CLOUDS IS EXPECT ON MONDAY
AS THE HIGH MOVES SOUTHEAST AND WINDS BECOME MORE SOUTHEASTERLY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 330 PM CST SUN JAN 3 2016
SEVERAL CONCERNS OVER THE NEXT 7 DAYS IN TERMS OF PRECIPITATION
TYPE/SNOWFALL RATIOS AND SFC TEMPS WHICH WILL LEAD TO
UNCERTAINTIES OF SNOWFALL AMTS.
TUESDAY/TUESDAY NIGHT WILL BE DRY...BUT WINDS WILL SHIFT TO THE
SOUTH AND COMMENCE THE MUCH MILDER CONDS FOR WED/THU/FRI BEFORE
PROBABLY THE COLDEST AIR OF THE SEASON MOVES IN NEXT WEEKEND.
FIRST...THE SYSTEM MOVING INTO SOUTHERN CALIFORNIA OVER THE NEXT
12-24 HRS WILL BE THE FIRST INGREDIENT FOR PRECIPITATION TO
DEVELOP LATE WEDNESDAY AFTN/EVENING AS ENERGY FROM THIS SYSTEM
MOVES NE ACROSS THE UPPER MIDWEST. THIS SYSTEM WILL BE RELATIVELY
MOISTURE STARVED INITIALLY...BUT WITH THE INCREASING SOUTHERLY
FLOW AHEAD AND BEHIND IT...QPF AMTS WILL LIKELY INCREASE IN FUTURE
MODEL RUNS. ALSO THIS WILL SET THE STAGE FOR LATE IN THE WEEK AS
ANOTHER SYSTEM MOVES IN...WITH PRECIPITABLE WATER VALUES
INCREASING TO OVER 0.50". ALTHOUGH WEDNESDAY SYSTEM WILL BE COLD
ENOUGH INITIALLY FOR ALL SNOW...AM CONCERN AT THE END AS WET-BULB
TEMPS IN THE FIRST 0-1KM INCREASES TO AROUND +0.5C ALONG THE MN/IA
BORDER. AT LEAST ONCE SNOW DEVELOPS AND SFC TEMPS RISE TO NEAR
FREEZING OR SLIGHTLY ABV...SNOWFALL WILL LIKELY BE LIMITED WITH
SNOWFALL RATIOS DROPPING TO AROUND 8-1 OR 5-1. THIS LEADS TO
SNOWFALL AMOUNTS OF LESS THAN ONE INCH FOR MOST AREAS THAT STAY
ALL SNOW. OUR SNOWFALL PROBABILITIES HAVE A BETTER CHANCE OF 1-2"
OUTSIDE OUR GREATEST QPF AREAS WEST/NW OF THE TWIN CITIES METRO
AREA. SEE THE LATEST TRENDS ON OUR WEB PAGE.
WWW.WEATHER.GOV/MPX/WINTER.
ONCE WEDNESDAY SYSTEM MOVES OFF...THERE SHOULD BE A BREAK IN THE
PRECIPITATION UNTIL LATE THURSDAY NIGHT/FRIDAY DEPENDING UPON THE
SPEED OF THE NEXT SHORTWAVE MOVING OUT OF THE DESERT SW LATE IN
THE WEEK. MOST MODELS HAVE THE BEST TIME FRAME OF PRECIPITATION
DEVELOPING FRIDAY AFTERNOON/EVENING...AND SLOWLY EXITING THE AREA
SATURDAY. HAVE INCREASED POPS TO LIKELY FOR PORTIONS OF MPX CWA
FRIDAY/FRIDAY NIGHT...BUT STILL SOME UNCERTAINTIES ON LOCATION OF
THE BEST LIFT AND SFC FEATURES. BASED ON THE LATEST MODEL
RUNS...IT IS LIKELY THAT THIS SYSTEM WILL BE WARM ENOUGH FOR A
PERIOD OF RAIN OR RAIN/SNOW MIX IN MPX SE CWA. OR BASICALLY FROM
SC TO EC MN AND INTO WC WI. DEPENDING UPON THE UPPER LEVEL
FEATURES...THE WARMER AIR COULD ACTUALLY MOVE FURTHER TO THE NW
ALLOWING FOR MOST OF THE AREA TO SEE RAIN/SNOW BEFORE COLDER AIR
ARRIVES SATURDAY. AGAIN...THIS IS BASED ON THE CURRENT MODEL RUNS
WHICH IS TOO FAR OUT TO GUARANTEE ANY EXACT QPF AND SNOWFALL AMTS.
EVEN IF THE SYSTEM IS COLD ENOUGH FOR ALL SNOW...SNOWFALL RATIOS
WILL LIKELY BE NEAR 10-1 OR LOWER AROUND 6 OR 8-1.
THEREFORE...KEEPING SNOWFALL AMOUNTS ON THE LOW SIDE. SFC TEMPS
WILL REFLECT THE MILDER AIR WITH READINGS HOLDING NEAR FREEZING OR
SLIGHTLY ABOVE ONCE THE PRECIPITATION DEVELOPS.
DUE TO THE FACT THE MODELS HAVE TRENDED TOWARD A LARGE AREA OF
COLD AIR FROM NORTHEAST CANADA TO MOVE SOUTHWARD NEXT
WEEKEND...THE PROBABILITY OF THE COLDEST AIR OF THE SEASON WILL
ARRIVE LATE NEXT WEEKEND AND INTO EARLY NEXT WEEK. OUR FIRST BELOW
ZERO READING /MPX CWA WIDE/ IS ALSO LIKELY DURING THIS TIME
FRAME. IN ADDITION...THE EPO /EASTERN PACIFIC OSCILLATION/ WHICH
IS CURRENTLY NEGATIVE AND WILL REMAIN NEGATIVE THROUGH THE 13TH OF
JANUARY...LEADS TO MUCH COLDER AIR PROBABILITIES ACROSS THE
NORTHERN PLAINS/UPPER MIDWEST. THIS IS THE SAME SCENARIO WITH WPC
BELOW NORMAL TEMPS FOR THE 6-14 DAY TIME PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1151 AM CST SUN JAN 3 2016
SATELLITE SHOWS NICE CLEARING OVER NORTHWEST MN SLIDING SOUTH.
THIS TREND SHOULD CONTINUE FOR THE NEXT FEW HOURS AND THEN CLOUDS
SHOULD BUILD BACK TO THE NORTH AND WEST AFTER 22Z. KAXN SHOULD
SCATTER OUT FOR A COUPLE OF HOURS. OVERALL IT LOOKS LIKE THE MVFR
STRATUS DECK WILL BE HERE TO STAY THE REMAINDER OF THE AFTERNOON
EVERYWHERE BUT KAXN. SOME MODEL SOLUTIONS TRY SCATTERING CLOUDS
OUT THIS EVENING...HOWEVER...GIVEN THE CLOUD DEPTH/EXTENT AND THE
TIME OF YEAR...WE THINK IT IS BETTER TO KEEP THE CLOUDS IN PLACE
AT MOST LOCATIONS FOR AWHILE. WOULD NOT BE SURPRISED TO SEE DECKS
LOWER TO THE LOW END OF MVFR AS WINDS BECOME SOUTHEAST AND VERY
LIGHT. ONCE WE GET PAST MID DAY MONDAY WE SHOULD SEE SCATTERING AT
MOST LOCATIONS WEST OF THE MN- WI BORDER. CEILINGS WILL REMAIN
ALL DAY MONDAY IN WESTERN WI.
KMSP...
CEILINGS ARE SLOWING RAISING AS SLIGHTLY DRIER AIR MOVES TOWARD
THE FIELD FROM THE NORTHWEST AND THE NORTH. WILL SEE A SCATTERING
OF THE CEILING IN THE OVERNIGHT HOURS. IT WOULD BE EASY ENOUGH TO
FORM A CEILING SO CONFIDENCE IS NOT HIGH AT THE MOMENT. CONFIDENCE
IS HIGH REGARDING A CEILING AND A LOWERING OF THE CEILING IN THE
MORNING HOURS AS LOW END MVFR CONDITIONS BUILD NORTH TOWARD MSP.
DO NOT EXPECT TO KEEP THE MVFR CONDITIONS ALL AFTERNOON.
/OUTLOOK FOR KMSP/
TUE...VFR. WINDS S 8-16 KTS.
WED...VFR. WINDS 5-12 KTS. SLIGHT CHANCE OF LIGHT SNOW.
THU...VFR. WINDS SE 5-10 KTS. CHANCE OF LIGHT SNOW.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...DRL
LONG TERM...JLT
AVIATION...DRL
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
446 AM CST SUN JAN 3 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 446 AM CST SUN JAN 3 2016
THE BIGGEST WEATHER CHALLENGE TODAY IS THE CLOUD FORECAST. THE
WIDESPREAD STRATUS DECK WITH BASES AT 1000-2000FT HAS FORMED IN
RESPONSE TO ROBUST COLD ADVECTION BETWEEN 925MB-700MB. DEEPER
MOISTURE AND A BETTER CHANCE FOR LIGHT SNOW/FLURRIES REMAINS WELL TO
THE NORTHEAST OF THE FORECAST AREA IN THE WAKE OF THE SURFACE LOW
MOVING ACROSS THE GREAT LAKES. THE NORTHWEST WINDS THIS MORNING ARE
THE RESULT OF THIS SURFACE LOW TO THE EAST AND A 1030-1035MB HIGH
BUILDING IN ACROSS THE NORTHERN PLAINS. THE CLOUDS WILL BE SLOW TO
CLEAR TODAY AND WITH THE HIGH MOVING OVERHEAD THIS EVENING...ANY
CLOUDS THAT DONT CLEAR BY SUNSET WILL LIKELY HAVE A HARD TIME
SCATTERING OUT OVERNIGHT. THIS WILL THEREFORE INFLUENCE OUR SUNDAY
NIGHT LOWS. THE CLOUDS COULD KEEP US FROM BOTTOMING OUT BELOW MOST
OF THE MODEL GUIDANCE...WHICH WOULD BE POSSIBLE GIVEN THE SNOW COVER
AND LIKELIHOOD OF STRONG RADIATIONAL COOLING WITH SUBSIDENCE UNDER
THE HIGH. ASIDE FROM THE CLOUD COVER...DRY CONDITIONS AND NEAR
NORMAL TEMPS ARE EXPECTED TODAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 446 AM CST SUN JAN 3 2016
MAIN AREA OF FOCUS REVOLVES AROUND THE STORM SYSTEM FOR THE LATTER
HALF OF THE WEEK THAT WILL BRING A WINTRY MIX OF SNOW AND RAIN
ACROSS THE REGION. THIS STORM SYSTEM NEVER REALLY GETS
ORGANIZED...SO AT THIS POINT IT LOOKS LIKE LIGHT TO MODERATE SNOW
ACCUMULATIONS ARE POSSIBLE. TEMPERATURES WILL BE NEAR TO ABOVE
NORMAL THROUGH THE PERIOD.
THIS SYSTEM CAN BE TRACED BACK TO A SERIES OF PV ANOMALIES CURRENTLY
LOCATED IN THE NORTHERN PACIFIC ON THE POLEWARD SIDE OF AN UPPER LEVEL
JET. BY THE TIME WEDNESDAY NIGHT ROLLS AROUND THE TROUGH AND JET MAX
WILL BE ACROSS THE BAJA TOWARD THE TEXAS PANHANDLE. OVER THE NEXT
FEW DAYS A INVERTED SURFACE TROUGH WILL PERSIST ACROSS THE
MIDWEST...WITH A LONG DURATION OF LIGHT PRECIPITATION EXPECTED.
SURFACE TEMPS HOOVER AROUND 30 TO 34F...SO PTYPE AND ACCUMULATIONS
ARE SUBJECT TO CHANGE OVER THE NEXT FEW DAYS. FOR EXAMPLE...THE
03.00Z GFS HAS OVER AN INCH OF QPF AT KMSP...BUT LESS THAN 3 INCHES
OF SNOWFALL ACCUMULATION. MEANWHILE...KAXN ALSO HAS OVER AN INCH OF
SNOW...WITH OVER 10 INCHES OF SNOWFALL.
AS OF NOW...THERE IS NOT AN ELEVATED WARM LAYER...SO DONT ANTICIPATE
FREEZING RAIN TO BE A PROBLEM. THE WEATHER TYPE SHOULD BE EITHER
RAIN OR SNOW. ALSO...THERE DOESNT APPEAR TO BE MUCH POTENTIAL FOR
THIS STORM TO DEVELOP INTO A MAJOR CYCLONE BECAUSE OF THE LACK
LUSTER LOW LEVEL THERMAL GRADIENT. THE MODEL SOLUTIONS MAY VERY WELL
CHANGE OVER THE NEXT COUPLE OF DAYS...BUT THIS BAGGY TEMPERATURE
GRADIENT SEEMS TO BE THE LIMITING FACTOR FOR RAPID CYCLOGENESIS. IN
FACT...FROM THURSDAY MORNING THROUGH SATURDAY NIGHT...THE SURFACE
PRESSURE FLUCTUATES FROM 1003MB TO 998MB.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 615 PM CST SAT JAN 2 2016
MAIN CONCERN IS LARGE AREA OF MVFR CEILINGS MOVING SOUTHWARD THIS
EVENING. SATELLITE AND OBS INDICATE IT EXTENDING ACROSS THE
NORTHERN 1/4 OF MN AND WELL INTO MANITOBA AND NW ONTARIO.
SATELLITE SUGGESTS THERE ARE A COUPLE POCKETS OF CLEARING IN NW
ONTARIO... BUT NOT ENOUGH OBS TO CORROBORATE HOW EXTENSIVE IT
REALLY IS. THIS WILL PLAY A ROLE IN CEILINGS IN OUR AREA TOMORROW.
THERE ARE HINTS IN THE LAMP AND LATEST RAP GUIDANCE OF MAYBE 2-3
HOURS OF SCATTERED SKIES. THUS HAVE ADDED THIS POSSIBILITY OF
SCATTERED CLOUDS AROUND 12Z TO THE WISCONSIN SITES...BUT THIS WILL
NEED TO BE WATCHED AND POSSIBLY EXTENDED WESTWARD.
ONE INTERESTING ITEM IN SOME OF THE GUIDANCE SUGGESTS PART OF
WEST CENTRAL MN...INCLUDING KAXN...MAY CLEAR OUT ENOUGH FOR
RADIATIONAL FOG TO DEVELOP AROUND 12Z WITH IFR A SMALL
POSSIBILITY. WILL SEE IF THIS TREND CONTINUES IN THE GUIDANCE.
KMSP...
MVFR CEILINGS AROUND 020 SEEM TO BE ON TRACK FOR AROUND
04Z...THEN SHOULD LOWER BELOW 017 LATER TONIGHT INTO SUNDAY
MORNING. MAIN QUESTION IS WHETHER A POCKET OF DRY AIR NOW IN NW
ONTARIO REACHES KMSP 12Z-15Z SUNDAY. NOT CONFIDENT ENOUGH TO ADD
THIS YET. THUS HAVE JUST GONE OVC OR BKN THROUGH MUCH OF THE
TAF...WITH LITTLE IMPROVEMENT UNTIL SUNDAY EVENING.
/OUTLOOK FOR KMSP/
MON...VFR. WINDS N 5 KTS BECOMING SE AT 5-10 KTS.
TUE...VFR. WINDS S 8-15 KTS.
WED...VFR. SLIGHT CHANCE LIGHT SNOW. WINDS S 5-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...CLF
LONG TERM...JRB
AVIATION...TDK
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
506 PM CST MON JAN 4 2016
.DISCUSSION...
Issued at 340 PM CST MON JAN 4 2016
Near term concerns center around the stratus deck lying under the
western half of a departing surface high. The visible and 11u-3.9u
satellite imagery revealed how thin this cloud deck was over the CWA
and as a result we saw much scattering of the deck during the
afternoon hours. Do think the stratus will reform over northwest MO
this evening. However, also expect the clearing seen over central MO
will work its way northwest overnight. The latest RAP now is in line
with the clearing shown by NAM 950mb condensation pressure deficit
progs. Overnight shift will need to monitor for potential fog
development along the periphery of the stratus.
All operational progs continue to show a rather wet period starting
as early as Wednesday morning as the first in a serious of features
work their way through the Central Plains and Mid MO River Valley.
GFS, ECMWF and SREF are in synch timing-wise with the first
shortwave, currently lifting northeast out of AZ. Warm advection
zone preceding this feature will overspread the CWA Wednesday. Have
raised PoPs. Inspection of NAM/GFS Bufr soundings continue to
support a chance of mixed precipitation. Currently the models show a
minimal warm nose aloft so either light freezing rain or snow (no
warm nose) are possible. QPF will be quite light with either one,
but enough that travel problems are possible for the morning rush
commute to work.
While a second shortwave will arrive on Thursday the increasingly
moist isentropic ascent could yield areas of drizzle/patchy rain
overnight Wednesday so high chance PoPs used. Steady moderate warm
air advection through a deep layer will allow temperatures to remain
above freezing through Friday. So, precipitation will be all liquid.
Friday night could bring a mix of rain and snow to the region as the
deformation zone lifts through the region. Quite a bit of difference
between the strength of the upper system/associated surface low with
the GFS considerably stronger. Given how much energy remains back to
the southwest within an elongated longer upper trough have little
confidence in a strong or well developed surface low. So, have not
bit on the GFS snow output.
Much colder air filters into the region over the weekend with
temperatures struggling to recover on Saturday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
Issued at 501 PM CST MON JAN 4 2016
MVFR ceilings are beginning to redevelop upstream as low-level
stratus remains trapped underneath the boundary layer. A few pockets
may clear periodically overnight, though MVFR ceilings should hold on
until Tuesday morning. Winds will then transition to southerly while
increasing into the afternoon.
&&
.EAX Watches/Warnings/Advisories...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...MJ
AVIATION...Welsh
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1204 PM CST SUN JAN 3 2016
.SHORT TERM: (Today and Tonight)
Issued at 300 AM CST Sun Jan 3 2016
A longwave trof centered thru eastern NOAM is producing NW flow
aloft across the area. Models maintain this regime with some
deepening of the longwave as a short wave trof digs into the lower
Great Lakes/Ohio Valley region today. This will help bring a
secondary cold front through the region this morning with low
level winds veering to N/NW and good CAA in its wake. Clouds today
in the CAA pattern are the most difficult part of this forecast,
and overall the models are not doing a great job in resolving the
stratus presently to our north and its future. Extrapolation of
the stratus and 950 mb RH progs from the RAP and NAM collectively
indicate the stratus will overspread much of the area from the
north after 15z. Temps are tricky. The front is through KUIN, and
elsewhere ahead of the front they have been pretty steady and are
close to previously forecast max temps. I have boosted highs a tad
with the idea they will fall a little through sunrise and then
rebound slightly before the stronger CAA kicks in and clouds
arrive. Northwest flow persists tonight with an impressive 1035+
surface high building from the northern Plains into the MS Valley.
I have boosted sky cover tonight from the previous forecast
closely following the NAM 950 RH progs which suggests the clouds
will be maintained until at least Monday. Temps tonight will be
rather cold - this will be some of the coldest air we have seen
this winter.
Glass
.LONG TERM: (Tonight through Saturday)
Issued at 300 AM CST Sun Jan 3 2016
Clouds issues today and tonight carry into Monday. Confidence in
their future wanes in this time frame, especially with only the
NAM 950 RH progs suggesting any stratus at all. I have allowed
the clouds to break up on Monday, but I would not at all be
surprised to see significantly more cloud cover than I have
forecast and cooler temps given the dominant surface high.
Eventually a pattern change will ensue late Monday into Tuesday as
the surface high retreats and ridging aloft moves in from the
Plains in association with a more progressive pattern evolving.
The attendant low level WAA should help lead to the departure of
any remaining low clouds and also warmer temps on Tuesday.
The next threat of measurable precipitation looks to unfold
Wednesday night and ramp up into the later part of the week ahead.
We will need to keep an eye on pytpe late Wednesday Night into
Thursday morning for northeast MO and west central IL. Surface
temps could be close to freezing and its not completely out of
the question there could be a brief period of freezing rain.
However the preferred GFS and ECMWF 2m temps are above freezing
and suggest all rain. A formidable and progressive upper trof will
move into the area late Thursday into Friday producing the
greatest chance of rainfall. Present indications are the
precitation may be over by the time deeper cold air arrives on
Saturday morning, however will maintain a chance of rain/snow.
Glass
&&
.AVIATION: (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1155 AM CST Sun Jan 3 2016
Primary concern is the large area of stratus moving south into the
area. Stratus looks like it should be mostly MVFR over our area,
but IFR ceilings look likely over parts of northeast Missouri.
Looks like the stratus will keep moving south through the day to
overspread the entire area by early this evening. MVFR ceilings
will likely drop to IFR across much of central and northeast
Missouri...possibly into east central and southeast Missouri as
well before sunrise Monday. There`s a good possibility that MVFR
ceilings will prevail through much of if not all of the day on
Monday as well.
Specifics for KSTL:
Watching the area of stratus moving south out of Iowa toward
Lambert this afternoon. Current estimates given position and speed
are that the stratus should reach Lambert between 22-23Z. Ceilings
below 2000 FT should prevail at least through Monday morning...and
probably through Monday afternoon as well after the stratus
overspreads the terminal. There is a chance we could see ceilings
below 1,000 FT as well before sunrise, but current thinking is
that the IFR will stay west of the terminal.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
1159 AM CST SUN JAN 3 2016
.UPDATE...
Issued at 953 AM CST SUN JAN 3 2016
Based on satellite trend and short term model guidance of large
stratus deck over IA/MN/WI have made a significant adjustment to
cloud cover for today. Using NAM/RAP 950mb condensation pressure
deficit prog as a guide and will gradually overspread the CWA with
stratus deck...reaching the MO River between 21Z-00Z. Have also
raised max temperatures a few degrees over the far southern counties
where no snow/ice cover remains and cold air advection has been a
little slower to arrive.
&&
.DISCUSSION...
Issued at 322 AM CST SUN JAN 3 2016
In the short term, the main concern will be stratus currently
advancing southward across the northern Plains, and how much of the
CWA it will impact today. The only models with a grasp on the
current extent and progression of the stratus are the RAP and HRRR,
but earlier runs of these models have shown the southwestern edges
mixing out more than has yet occurred, and conceptually expect the
cold air advection to help reinforce and push the stratus southward.
As a result, have significantly increased cloud cover through most
of the forecast area from late morning through the early afternoon,
then begin to pull the back edge of the stratus eastward as the
trough dipping into the Great Lakes begins to also shift east. The
combination of reduce insolation and CAA will also support chilly
temperatures, so have kept the 10 to 15 degree departure in highs
from yesterday, and even shied a bit cooler as a trend toward the
HRRR/RAP solutions.
Stratus may linger in the eastern third of the CWA overnight and
into early Monday morning before dissipating, possibly holding low
temperatures up a few degrees over model guidance. Chilly Canadian
surface high pressure will then advance across the region on Monday,
holding temperatures in the upper 20s to lower 30s even as northerly
winds become light and variable and at least partial sunshine
spreads throughout the area. After the surface high drifts out of
the region, southerly flow will gradually return, allowing for a
warming trend from Tuesday through the end of the work week.
The next chance for precipitation will still begin midweek as a
broad upper trough pushes developing surface low pressure out of the
central High Plains and into the forecast area by Friday. The open
character of the wave and the west-to-east track of the surface low,
in addition to the limited window for moisture return, both indicate
that precipitation with this system will be light. Models are still
in agreement that the majority of precipitation will be liquid as
warmer air surges northward ahead of the surface low, except a short
period late Tuesday night into Wednesday morning when a few flurries
or perhaps some patchy freezing drizzle is possible as the column
begins to saturate at low levels and isentropic lift begins. Model
consensus still drives temperatures a few degrees below freezing on
Wednesday night despite the continued agreement that precipitation
will fall through an entirely above-freezing column, so have
included a small chance for mixed wintry precipitation on the north
side of the precipitation shield where temperatures are a bit
cooler. Otherwise, do not expect any mix with or changeover to snow
until the surface low passes east of the forecast area, and although
some light precipitation does wrap around the back side of the low
where temperatures aloft begin to cool, currently not anticipating
any snow accumulations due to low moisture availability and the
brevity of the window for precipitation coincident with supportive
temperatures.
Colder temperatures do look possible in the wake of this system,
and more likely just beyond the end of the forecast period, possibly
bringing some of the coldest conditions yet this season by next
weekend into early in the following week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1154 AM CST SUN JAN 3 2016
Extensive area of IFR/low-end MVFR stratus deck over IA/MN will
continue to spread southward, reaching the MO River around 00Z. The
southward progress has slowed due to mixing and solar heating but
believe the stratus will accelerate after sunset. Once the stratus
arrives it will likely last well into Monday afternoon. If no breaks
in the cloud cover occur by afternoon there is a good chance MVFR
ceilings would then last through Monday night. Could also see a few
flurries here and there but no accumulating snow.
&&
.EAX Watches/Warnings/Advisories...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...MJ
DISCUSSION...Laflin
AVIATION...MJ
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
958 AM CST SUN JAN 3 2016
.UPDATE...
Issued at 953 AM CST SUN JAN 3 2016
Based on satellite trend and short term model guidance of large
stratus deck over IA/MN/WI have made a significant adjustment to
cloud cover for today. Using NAM/RAP 950mb condensation pressure
deficit prog as a guide and will gradually overspread the CWA with
stratus deck...reaching the MO River between 21Z-00Z. Have also
raised max temperatures a few degrees over the far southern counties
where no snow/ice cover remains and cold air advection has been a
little slower to arrive.
&&
.DISCUSSION...
Issued at 322 AM CST SUN JAN 3 2016
In the short term, the main concern will be stratus currently
advancing southward across the northern Plains, and how much of the
CWA it will impact today. The only models with a grasp on the
current extent and progression of the stratus are the RAP and HRRR,
but earlier runs of these models have shown the southwestern edges
mixing out more than has yet occurred, and conceptually expect the
cold air advection to help reinforce and push the stratus southward.
As a result, have significantly increased cloud cover through most
of the forecast area from late morning through the early afternoon,
then begin to pull the back edge of the stratus eastward as the
trough dipping into the Great Lakes begins to also shift east. The
combination of reduce insolation and CAA will also support chilly
temperatures, so have kept the 10 to 15 degree departure in highs
from yesterday, and even shied a bit cooler as a trend toward the
HRRR/RAP solutions.
Stratus may linger in the eastern third of the CWA overnight and
into early Monday morning before dissipating, possibly holding low
temperatures up a few degrees over model guidance. Chilly Canadian
surface high pressure will then advance across the region on Monday,
holding temperatures in the upper 20s to lower 30s even as northerly
winds become light and variable and at least partial sunshine
spreads throughout the area. After the surface high drifts out of
the region, southerly flow will gradually return, allowing for a
warming trend from Tuesday through the end of the work week.
The next chance for precipitation will still begin midweek as a
broad upper trough pushes developing surface low pressure out of the
central High Plains and into the forecast area by Friday. The open
character of the wave and the west-to-east track of the surface low,
in addition to the limited window for moisture return, both indicate
that precipitation with this system will be light. Models are still
in agreement that the majority of precipitation will be liquid as
warmer air surges northward ahead of the surface low, except a short
period late Tuesday night into Wednesday morning when a few flurries
or perhaps some patchy freezing drizzle is possible as the column
begins to saturate at low levels and isentropic lift begins. Model
consensus still drives temperatures a few degrees below freezing on
Wednesday night despite the continued agreement that precipitation
will fall through an entirely above-freezing column, so have
included a small chance for mixed wintry precipitation on the north
side of the precipitation shield where temperatures are a bit
cooler. Otherwise, do not expect any mix with or changeover to snow
until the surface low passes east of the forecast area, and although
some light precipitation does wrap around the back side of the low
where temperatures aloft begin to cool, currently not anticipating
any snow accumulations due to low moisture availability and the
brevity of the window for precipitation coincident with supportive
temperatures.
Colder temperatures do look possible in the wake of this system,
and more likely just beyond the end of the forecast period, possibly
bringing some of the coldest conditions yet this season by next
weekend into early in the following week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 536 AM CST SUN JAN 3 2016
Stratus will continue to push southward out of IA and into northern
MO today, but may stay just east of the terminals. If stratus does
brush any of the TAF sites, it is currently progged to arrive between
20z-23z this afternoon. Otherwise, north northwest winds around 10
kts are expected today, then will become light and variable by Monday
morning.
&&
.EAX Watches/Warnings/Advisories...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...MJ
DISCUSSION...Laflin
AVIATION...Laflin
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
539 AM CST SUN JAN 3 2016
.SHORT TERM: (Today and Tonight)
Issued at 300 AM CST Sun Jan 3 2016
A longwave trof centered thru eastern NOAM is producing NW flow
aloft across the area. Models maintain this regime with some
deepening of the longwave as a short wave trof digs into the lower
Great Lakes/Ohio Valley region today. This will help bring a
secondary cold front through the region this morning with low
level winds veering to N/NW and good CAA in its wake. Clouds today
in the CAA pattern are the most difficult part of this forecast,
and overall the models are not doing a great job in resolving the
stratus presently to our north and its future. Extrapolation of
the stratus and 950 mb RH progs from the RAP and NAM collectively
indicate the stratus will overspread much of the area from the
north after 15z. Temps are tricky. The front is through KUIN, and
elsewhere ahead of the front they have been pretty steady and are
close to previously forecast max temps. I have boosted highs a tad
with the idea they will fall a little through sunrise and then
rebound slightly before the stronger CAA kicks in and clouds
arrive. Northwest flow persists tonight with an impressive 1035+
surface high building from the northern Plains into the MS Valley.
I have boosted sky cover tonight from the previous forecast
closely following the NAM 950 RH progs which suggests the clouds
will be maintained until at least Monday. Temps tonight will be
rather cold - this will be some of the coldest air we have seen
this winter.
Glass
.LONG TERM: (Tonight through Saturday)
Issued at 300 AM CST Sun Jan 3 2016
Clouds issues today and tonight carry into Monday. Confidence in
their future wanes in this time frame, especially with only the
NAM 950 RH progs suggesting any stratus at all. I have allowed
the clouds to break up on Monday, but I would not at all be
surprised to see significantly more cloud cover than I have
forecast and cooler temps given the dominant surface high.
Eventually a pattern change will ensue late Monday into Tuesday as
the surface high retreats and ridging aloft moves in from the
Plains in association with a more progressive pattern evolving.
The attendant low level WAA should help lead to the departure of
any remaining low clouds and also warmer temps on Tuesday.
The next threat of measurable precipitation looks to unfold
Wednesday night and ramp up into the later part of the week ahead.
We will need to keep an eye on pytpe late Wednesday Night into
Thursday morning for northeast MO and west central IL. Surface
temps could be close to freezing and its not completely out of
the question there could be a brief period of freezing rain.
However the preferred GFS and ECMWF 2m temps are above freezing
and suggest all rain. A formidable and progressive upper trof will
move into the area late Thursday into Friday producing the
greatest chance of rainfall. Present indications are the
precitation may be over by the time deeper cold air arrives on
Saturday morning, however will maintain a chance of rain/snow.
Glass
&&
.AVIATION: (For the 12z TAFs through 12z Monday Morning)
Issued at 530 AM CST Sun Jan 3 2016
Main forecast concern for the valid forecast period will be on
MVFR stratus deck currently across the Upper Midwest. RAP has
handled this stratus event very well overnight so relied on it for
timing and ceiling trends through this afternoon. Thereafter...NAM
model seemed to be handling it best as it holds in clouds
overnight tonight as well as slightly lowers ceilings. Timing of
stratus onset at KUIN looks to be around 1700 UTC...and KCOU and
the metro TAFS around 2000-2100 UTC. A lowering below 2000 feet
appears likely at all sites by this evening.
Specifics for KSTL:
Stratus should arrive at Lambert around 2000 UTC this afternoon
and then lower below 2000 feet this evening. Guidance suggests
ceilings should not only rise by late Monday morning...but also
scatter out...though would not be shocked if once again models are
too optimistic.
Gosselin
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 37 23 33 23 / 0 0 0 0
Quincy 31 19 30 19 / 0 0 0 0
Columbia 34 21 32 20 / 0 0 0 0
Jefferson City 38 21 34 20 / 0 0 0 0
Salem 37 24 33 22 / 0 0 0 0
Farmington 38 21 33 20 / 0 0 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
536 AM CST SUN JAN 3 2016
.DISCUSSION...
Issued at 322 AM CST SUN JAN 3 2016
In the short term, the main concern will be stratus currently
advancing southward across the northern Plains, and how much of the
CWA it will impact today. The only models with a grasp on the
current extent and progression of the stratus are the RAP and HRRR,
but earlier runs of these models have shown the southwestern edges
mixing out more than has yet occurred, and conceptually expect the
cold air advection to help reinforce and push the stratus southward.
As a result, have significantly increased cloud cover through most
of the forecast area from late morning through the early afternoon,
then begin to pull the back edge of the stratus eastward as the
trough dipping into the Great Lakes begins to also shift east. The
combination of reduce insolation and CAA will also support chilly
temperatures, so have kept the 10 to 15 degree departure in highs
from yesterday, and even shied a bit cooler as a trend toward the
HRRR/RAP solutions.
Stratus may linger in the eastern third of the CWA overnight and
into early Monday morning before dissipating, possibly holding low
temperatures up a few degrees over model guidance. Chilly Canadian
surface high pressure will then advance across the region on Monday,
holding temperatures in the upper 20s to lower 30s even as northerly
winds become light and variable and at least partial sunshine
spreads throughout the area. After the surface high drifts out of
the region, southerly flow will gradually return, allowing for a
warming trend from Tuesday through the end of the work week.
The next chance for precipitation will still begin midweek as a
broad upper trough pushes developing surface low pressure out of the
central High Plains and into the forecast area by Friday. The open
character of the wave and the west-to-east track of the surface low,
in addition to the limited window for moisture return, both indicate
that precipitation with this system will be light. Models are still
in agreement that the majority of precipitation will be liquid as
warmer air surges northward ahead of the surface low, except a short
period late Tuesday night into Wednesday morning when a few flurries
or perhaps some patchy freezing drizzle is possible as the column
begins to saturate at low levels and isentropic lift begins. Model
consensus still drives temperatures a few degrees below freezing on
Wednesday night despite the continued agreement that precipitation
will fall through an entirely above-freezing column, so have
included a small chance for mixed wintry precipitation on the north
side of the precipitation shield where temperatures are a bit
cooler. Otherwise, do not expect any mix with or changeover to snow
until the surface low passes east of the forecast area, and although
some light precipitation does wrap around the back side of the low
where temperatures aloft begin to cool, currently not anticipating
any snow accumulations due to low moisture availability and the
brevity of the window for precipitation coincident with supportive
temperatures.
Colder temperatures do look possible in the wake of this system,
and more likely just beyond the end of the forecast period, possibly
bringing some of the coldest conditions yet this season by next
weekend into early in the following week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 536 AM CST SUN JAN 3 2016
Stratus will continue to push southward out of IA and into northern
MO today, but may stay just east of the terminals. If stratus does
brush any of the TAF sites, it is currently progged to arrive between
20z-23z this afternoon. Otherwise, north northwest winds around 10
kts are expected today, then will become light and variable by Monday
morning.
&&
.EAX Watches/Warnings/Advisories...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...Laflin
AVIATION...Laflin
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
322 AM CST SUN JAN 3 2016
.DISCUSSION...
Issued at 322 AM CST SUN JAN 3 2016
In the short term, the main concern will be stratus currently
advancing southward across the northern Plains, and how much of the
CWA it will impact today. The only models with a grasp on the
current extent and progression of the stratus are the RAP and HRRR,
but earlier runs of these models have shown the southwestern edges
mixing out more than has yet occurred, and conceptually expect the
cold air advection to help reinforce and push the stratus southward.
As a result, have significantly increased cloud cover through most
of the forecast area from late morning through the early afternoon,
then begin to pull the back edge of the stratus eastward as the
trough dipping into the Great Lakes begins to also shift east. The
combination of reduce insolation and CAA will also support chilly
temperatures, so have kept the 10 to 15 degree departure in highs
from yesterday, and even shied a bit cooler as a trend toward the
HRRR/RAP solutions.
Stratus may linger in the eastern third of the CWA overnight and
into early Monday morning before dissipating, possibly holding low
temperatures up a few degrees over model guidance. Chilly Canadian
surface high pressure will then advance across the region on Monday,
holding temperatures in the upper 20s to lower 30s even as northerly
winds become light and variable and at least partial sunshine
spreads throughout the area. After the surface high drifts out of
the region, southerly flow will gradually return, allowing for a
warming trend from Tuesday through the end of the work week.
The next chance for precipitation will still begin midweek as a
broad upper trough pushes developing surface low pressure out of the
central High Plains and into the forecast area by Friday. The open
character of the wave and the west-to-east track of the surface low,
in addition to the limited window for moisture return, both indicate
that precipitation with this system will be light. Models are still
in agreement that the majority of precipitation will be liquid as
warmer air surges northward ahead of the surface low, except a short
period late Tuesday night into Wednesday morning when a few flurries
or perhaps some patchy freezing drizzle is possible as the column
begins to saturate at low levels and isentropic lift begins. Model
consensus still drives temperatures a few degrees below freezing on
Wednesday night despite the continued agreement that precipitation
will fall through an entirely above-freezing column, so have
included a small chance for mixed wintry precipitation on the north
side of the precipitation shield where temperatures are a bit
cooler. Otherwise, do not expect any mix with or changeover to snow
until the surface low passes east of the forecast area, and although
some light precipitation does wrap around the back side of the low
where temperatures aloft begin to cool, currently not anticipating
any snow accumulations due to low moisture availability and the
brevity of the window for precipitation coincident with supportive
temperatures.
Colder temperatures do look possible in the wake of this system,
and more likely just beyond the end of the forecast period, possibly
bringing some of the coldest conditions yet this season by next
weekend into early in the following week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1136 PM CST SAT JAN 2 2016
Widespread MVFR/IFR stratus is currently located over the eastern
Dakotas and Minnesota area and advancing south. The trajectory of
this advancing stratus would give it a glancing blow to the terminals
during the day on Sunday. There is some conflicting signals as to
whether or not the clouds will actually make it to the terminals and
bring flight restrictions. Current thinking is that there could be a
few hours of very thin scattered to broken low level clouds that
could bring off and on periods of MVFR CIGS through the day.
Confidence in prevailing MVFR CIGS was not very high as of this
forecast so entered a SCT015 grouping to indicate the general time
frame of the clouds` arrival. As the stratus advances south being
able to predict its effects on the area might be a bit higher.
&&
.EAX Watches/Warnings/Advisories...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...Laflin
AVIATION...Leighton
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
314 AM CST SUN JAN 3 2016
.SHORT TERM: (Today and Tonight)
Issued at 300 AM CST Sun Jan 3 2016
A longwave trof centered thru eastern NOAM is producing NW flow
aloft across the area. Models maintain this regime with some
deepening of the longwave as a short wave trof digs into the lower
Great Lakes/Ohio Valley region today. This will help bring a
secondary cold front through the region this morning with low
level winds veering to N/NW and good CAA in its wake. Clouds today
in the CAA pattern are the most difficult part of this forecast,
and overall the models are not doing a great job in resolving the
stratus presently to our north and its future. Extrapolation of
the stratus and 950 mb RH progs from the RAP and NAM collectively
indicate the stratus will overspread much of the area from the
north after 15z. Temps are tricky. The front is through KUIN, and
elsewhere ahead of the front they have been pretty steady and are
close to previously forecast max temps. I have boosted highs a tad
with the idea they will fall a little through sunrise and then
rebound slightly before the stronger CAA kicks in and clouds
arrive. Northwest flow persists tonight with an impressive 1035+
surface high building from the northern Plains into the MS Valley.
I have boosted sky cover tonight from the previous forecast
closely following the NAM 950 RH progs which suggests the clouds
will be maintained until at least Monday. Temps tonight will be
rather cold - this will be some of the coldest air we have seen
this winter.
Glass
.LONG TERM: (Tonight through Saturday)
Issued at 300 AM CST Sun Jan 3 2016
Clouds issues today and tonight carry into Monday. Confidence in
their future wanes in this time frame, especially with only the
NAM 950 RH progs suggesting any stratus at all. I have allowed
the clouds to break up on Monday, but I would not at all be
surprised to see significantly more cloud cover than I have
forecast and cooler temps given the dominant surface high.
Eventually a pattern change will ensue late Monday into Tuesday as
the surface high retreats and ridging aloft moves in from the
Plains in association with a more progressive pattern evolving.
The attendant low level WAA should help lead to the departure of
any remaining low clouds and also warmer temps on Tuesday.
The next threat of measurable precipitation looks to unfold
Wednesday night and ramp up into the later part of the week ahead.
We will need to keep an eye on pytpe late Wednesday Night into
Thursday morning for northeast MO and west central IL. Surface
temps could be close to freezing and its not completely out of
the question there could be a brief period of freezing rain.
However the preferred GFS and ECMWF 2m temps are above freezing
and suggest all rain. A formidable and progressive upper trof will
move into the area late Thursday into Friday producing the
greatest chance of rainfall. Present indications are the
precitation may be over by the time deeper cold air arrives on
Saturday morning, however will maintain a chance of rain/snow.
Glass
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1145 PM CST Sat Jan 2 2016
Short range models still showing stratus/sc deck making slow
progress to the south behind cold front. Has slowed down a bit, so
backed off on MVFR cigs til between 18z-22z Sunday. Otherwise,
west winds to veer to the northwest then to the north as system
moves through.
Specifics for KSTL:
Short range models still showing stratus/sc deck making slow
progress to the south behind cold front. Has slowed down a bit, so
backed off on MVFR cigs til between 21z-22z Sunday in metro area.
Otherwise, west winds to veer to the northwest by 11z Sunday then
to the north by 21z Sunday as system moves through.
Byrd
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 37 23 33 23 / 0 0 0 0
Quincy 31 19 30 19 / 0 0 0 0
Columbia 34 21 32 20 / 0 0 0 0
Jefferson City 38 21 34 20 / 0 0 0 0
Salem 37 24 33 22 / 0 0 0 0
Farmington 38 21 33 20 / 0 0 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1148 PM CST SAT JAN 2 2016
.UPDATE:
Issued at 928 PM CST Sat Jan 2 2016
No major changes to going forecast. Still watching stratus drop
south from MN and WI, but extrapolation of leading edge of cloud
deck indicates it wont arrive in northern sections of our CWA
until late tomorrow morning (at the earliest). It`s also possible
cloudiness will be more extensive over northeast sections of the
CWA by tomorrow afternoon. I have adjusted clouds up just a bit in
this area, and will let mid shift get a better handle on low cloud
trends before making additional adjustments.
Truett
&&
.SHORT TERM: (Through Late Tonight)
Issued at 323 PM CST Sat Jan 2 2016
Cold front over the Upper Midwest and northeast Plains will dive
south tonight, reaching the I-70 corridor by around 12Z. The latest
runs of the RAP, HRRR and NARRE-TL are now showing about the same,
while the GFS and GFS LAMP guidance are much drier in the low
levels. Ended up hinting at some clouds coming into the area late
tonight, but did not go as cloudy as what most short range guidance
suggests. Latest satellite pictures tho are tending to agree with
the short range guidance...so this forecast may need to be
overhauled later tonight if the clouds continue their march
southward. Used a blend of temperature guidance for lows tonight,
but ended up leaning toward the colder side which is closer to
persistence.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 323 PM CST Sat Jan 2 2016
Pcpn-free weather will persist across our region thru at least
Wednesday, as northwest flow aloft, and a mainly northerly flow at
the surface persists, keeping the column very dry. Thru Monday,
temps will be a bit below seasonal averages, but with a shift of the
low level flow from the south by Tuesday, temps are expected to
return to above average for daytime maxes.
Another interesting forecast issue will be what looks to be an
increasing chance for an extensive area of low level stratus clouds
to invade our region from the north late tonight or Sunday morning.
This stratus, if it does make it down here to any large degree, may
very well persist until Tuesday, when low level flow turns from the
south. Will take it a day at a time for now, with some clearing on
Monday, as confidence increases. Thicker more persistent clouds
will also favor more the lower MET MOS max temps Sunday, and perhaps
into Monday.
The next chance for widespread pcpn look to still be set for late
week, as flow aloft backs from the southwest and different Pacific
systems track across the country. A persistent model signal has
settled on the onset beginning at some point Wednesday night,
peaking Thursday night, and lingering to some extent into the
weekend.
Some good news with a slightly earlier onset is that it looks less
likely temps will cool down sufficiently for wintry pcpn types, and
with above freezing temps now expected, have kept the pcpn all rain
for now. Only on the back-end this weekend where colder air spills
in as the pcpn is pulling out may there be a relatively brief spat
of snow.
Temps should remain above average thru late week.
TES
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1145 PM CST Sat Jan 2 2016
Short range models still showing stratus/sc deck making slow
progress to the south behind cold front. Has slowed down a bit, so
backed off on MVFR cigs til between 18z-22z Sunday. Otherwise,
west winds to veer to the northwest then to the north as system
moves through.
Specifics for KSTL:
Short range models still showing stratus/sc deck making slow
progress to the south behind cold front. Has slowed down a bit, so
backed off on MVFR cigs til between 21z-22z Sunday in metro area.
Otherwise, west winds to veer to the northwest by 11z Sunday then
to the north by 21z Sunday as system moves through.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
544 PM CST MON JAN 4 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 404 PM CST MON JAN 4 2016
THE PRIMARY FORECAST CHALLENGES WILL CENTER AROUND LOW STRATUS AND
FOG DEVELOPMENT...ALONG WITH POTENTIAL IMPACT OF CLOUDS/FOG ON
TEMPERATURES.
THIS AFTERNOON THROUGH TONIGHT...LOW STRATUS HAS BEEN SLOW TO ERODE
AND REMAINS ACROSS PORTIONS OF OUR EASTERN FORECAST AREA THIS
AFTERNOON. THESE LOW STRATUS CLOUDS ARE EXPECTED TO EXPAND BACK
ACROSS THE AREA OVERNIGHT AS MOIST SOUTHERLY WINDS KICK UP ACROSS
THE REGION. RECENT RUNS OF THE HRRR HAVE BEEN VERY AGGRESSIVE WITH
GRADUALLY DEVELOPING FOG ACROSS MUCH OF THE FORECAST AREA AS WE HEAD
THROUGH THE OVERNIGHT HOURS. THEREFORE...WILL FORECAST AREAS OF FOG
TONIGHT AND MAY EVEN END UP NEEDING A DENSE FOG HEADLINE SHOULD THE
FOG FORM AND BECOME DENSE ENOUGH. NOT ENOUGH CONFIDENCE THIS FAR OUT
TO ISSUE A HEADLINE AS OF THIS AFTERNOON...BUT WOULD NOT BE
SURPRISED IF A DENSE FOG HEADLINE IS EVENTUALLY NEEDED LATER TONIGHT.
TUESDAY...MOST FORECAST MODELS KEEP A MAJORITY OF OUR FORECAST AREA
STUCK UNDER A LOW STRATUS DECK THROUGHOUT THE DAY. SOUTHWESTERN
ZONES SEEM TO STAND THE BEST CHANCE AT CATCHING SOME LATE DAY
SUNSHINE...BUT NO GRANTEES AS THIS FOG/LOW CLOUD FORECAST IS VERY
CHALLENGING. FOG WILL BE AT ITS WORST DURING THE CLIMATOLOGICALLY
FAVORABLE TIME...TUESDAY MORNING...AND THEN SHOULD BEGIN TO LIFT
INTO MORE OF A LOW STRATUS BY LATER IN THE MORNING/AFTERNOON. THE
SOUTHERLY WINDS WILL ADVECT WARMER AIR INTO THE REGION...BUT WITH
THICK LOW CLOUDS TEMPERATURES MAY HAVE A DIFFICULT TIME RISING
MUCH...ESPECIALLY OVER SNOW COVERED AREAS. CONFIDENCE IN THE
TEMPERATURE FORECAST IS LOWER THAN NORMAL WITH A WIDE SPREAD IN
MODEL TEMPERATURES DEPENDING ON IF ANY SUN CAN POKE THROUGH THE
CLOUDS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 404 PM CST MON JAN 4 2016
THIS 6-DAY PERIOD CAN BASICALLY BE BROKEN DOWN INTO 3 TIME
FRAMES WITH THEIR OWN UNIQUE HIGHLIGHTS/CHALLENGES...AND WILL
START OUT BY BREAKING THESE DOWN:
1) TUESDAY NIGHT-WEDNESDAY NIGHT: ALTHOUGH NO ACCUMULATING SNOW IS
CURRENTLY EXPECTED DURING THESE 36 HOURS DUE TO LACK OF SATURATION
ALOFT...THERE ARE LEGITIMATE CONCERNS FOR AT LEAST SOME SPOTTY
LIGHT FREEZING DRIZZLE/FREEZING RAIN MAINLY DURING THE NIGHT AND
EARLY MORNING HOURS. THERE COULD ALSO BE MORE FOG ISSUES AS
WELL...BUT GIVEN HOW UNCERTAIN/TRICKY FOG TRENDS CAN BE IN THIS
PATTERN...AND THAT WE ALREADY HAVE FOG MENTIONED IN THE SHORT TERM
PERIOD DESCRIBED ABOVE...WILL DEFER TO LATER SHIFTS TO INTRODUCE
ANY POSSIBLE NEED FOR FOG INTO THE OFFICIAL FORECAST FOR TUESDAY
NIGHT AND BEYOND.
2) THURSDAY DAYTIME-FRIDAY NIGHT: AS HAS BEEN THE CASE FOR THE
PAST SEVERAL DAYS...THIS 48-HOUR PERIOD STILL FEATURES THE
POTENTIAL "MAIN EVENT" OF THE WEEK IN TERMS OF POTENTIAL SNOW
ACCUMULATION. ALTHOUGH WE ARE CREEPING EVER-CLOSER...BECAUSE WE
ONLY ADVERTISE OFFICIAL SNOW ACCUMULATION FORECASTS THROUGH 72
HOURS...OUR CURRENT FORECAST DOES NOT INCLUDE ANY ACCUMULATION
DATA FOR THURSDAY NIGHT-FRIDAY...WHICH IS WHEN MOST SNOW IS
EXPECTED TO FALL. THAT BEING SAID...WITH THIS POSSIBLE SNOW EVENT
WITHIN 4 DAYS NOW...AND WITH MODELS SUCH AS THE 12Z ECMWF/GFS
SUGGESTING THAT AT LEAST A FEW INCHES COULD AFFECT PARTS OF THE
CWA...HAVE OPTED TO INTRODUCE A MENTION IN OUR LATEST HAZARDOUS
WEATHER OUTLOOK (HWOGID). OF COURSE...THERE IS STILL PLENTY OF
UNCERTAINTY ESPECIALLY REGARDING THE LOW-LEVEL TEMPERATURE PROFILE
AND JUST HOW QUICKLY/SLOWLY ESPECIALLY OUR SOUTHERN/SOUTHEAST
COUNTIES WILL CHANGE OVER FROM RAIN TO SNOW...AS RAIN COULD BE THE
PREDOMINANT PRECIPITATION TYPE MUCH OF THE TIME IN THIS AREA.
CONVERSELY...ALTHOUGH SNOW APPEARS TO BE THE MORE DOMINANT TYPE IN
ESPECIALLY NORTHERN/WEST-CENTRAL COUNTIES...THERE ARE QUESTIONS
HERE ABOUT HOW MUCH PRECIPITATION MIGHT ACTUALLY FALL COMPARED TO
COUNTIES FARTHER SOUTH AND EAST. THUS...IN THEORY...THIS COULD BE
A SITUATION WHERE CENTRAL PORTIONS OF THE CWA ACTUALLY SEE THE
HIGHEST SNOWFALL AMOUNTS IF TRENDS CONTINUE ON THEIR CURRENT
TRACK...WITH LESSER AMOUNTS NORTHWEST AND SOUTHEAST. STILL TOO
SOON TO SAY FOR SURE THOUGH...AND PLEASE NOTE THAT WE ARE 24-36
HOURS AWAY FROM ADVERTISING SNOW ACCUMULATION TOTALS THAT WILL
CAPTURE THE ENTIRE EVENT.
3) SATURDAY DAYTIME-MONDAY DAYTIME: THESE LAST 3 DAYS OF THE
FORECAST HAVE BEEN KEPT AS/INTRODUCED AS OFFICIALLY DRY...AS
ALTHOUGH IT`S NOT OUT OF THE QUESTION THAT SOME VERY LIGHT
SNOW/FLURRIES COULD MAYBE LINGER INTO AT LEAST SATURDAY MORNING
IN LATER FORECASTS (ESPECIALLY PER THE ECMWF SOLUTION)...THERE
APPEARS TO BE VERY LITTLE IF ANY CHANCE OF ANOTHER LEGITIMATE
WINTRY PRECIPITATION EVENT THROUGH THIS TIME. THAT MEANS THAT THE
MAIN STORY WILL TURN TOWARD COLDER-THAN-NORMAL TEMPERATURES.
ALTHOUGH MODELS ARE CERTAINLY NOT IN LOCK-STEP AT THIS DAY 5-7
RANGE (AS IS TYPICAL)...AT LEAST FOR NOW WE ARE AIMING HIGH
TEMPERATURES ONLY INTO THE 18-28 DEGREES RANGE ACROSS MOST OF THE
CWA...WHICH IS ROUGHLY 7-15 DEGREES BELOW AVERAGE/NORMAL FOR EARLY
JANUARY. IN TURN...OVERNIGHT LOW TEMPERATURES FROM SATURDAY NIGHT
ONWARD ARE EXPECTED TO DROP INTO THE SINGLE DIGITS ABOVE ZERO
ACROSS MUCH OF THE CWA.
WITH THE PRIMARY 3 WEATHER "REGIMES" AND THEIR CONCERNS BROKEN
DOWN ABOVE...WILL FINISH WITH A FAIRLY BRIEF LOOK AT A BIT MORE
METEOROLOGICAL DETAIL IN 12-60 HOUR BLOCKS:
TUESDAY EVENING/NIGHT: ALTHOUGH PREVIOUS FORECAST ALREADY
INTRODUCED THE POSSIBILITY OF SOME LIGHT FREEZING DRIZZLE IN FAR
SOUTHEAST COUNTIES...THIS LATEST PACKAGE HAS EXPANDED THIS "SLIGHT
CHANCE" MENTION OF FREEZING DRIZZLE AND/OR DRIZZLE TO ENCOMPASS
THE MAJORITY OF THE CWA...ASSUMING OF COURSE THAT WIDESPREAD LOW
STRATUS CLOUDS DO IN FACT DOMINATE THE AREA IN INCREASINGLY-MOIST
LOW LEVEL SOUTHERLY FLOW. VARIOUS 12Z/18Z MODELS ARE IN GOOD
AGREEMENT IN TRACKING THE FIRST LEGITIMATE-BUT-LOW-AMPLITUDE MID
LEVEL SHORTWAVE TROUGH OF THE WEEK NORTHEASTWARD ACROSS THE HEART
OF NEB/KS...THUS PROVIDING AT LEAST LOW-LEVEL LIFT FOR SOME
DRIZZLY ACTIVITY. THERE ARE HINTS THAT MAINLY THE FAR SOUTHEAST
CWA COULD SEE A QUICK BURST OF SNOW/POSSIBLY SLEET...BUT THIS
SEEMS MORE FAVORED OUTSIDE THE CWA WITHIN EASTERN KS. ASSUMING
PLENTIFUL CLOUDS AND SOUTHERLY SURFACE BREEZES GENERALLY 10-15
MPH...THIS SHOULD BE A SEASONABLY "MILD" NIGHT WITH LOWS ONLY
DROPPING TO AROUND 30 MOST PLACES.
WEDNESDAY/WEDNESDAY NIGHT: WHILE THE LOCAL AREA LARGELY SITS "IN
BETWEEN" UPPER LEVEL WAVES/FORCING DURING THIS TIME...THE PESKY
LOW-LEVEL STRATUS/SATURATION LOOKS TO PERSIST...AND THUS HAVE KEPT
A MENTION OF LIGHT RAIN/FREEZING RAIN OR LIGHT DRIZZLE/FREEZING
DRIZZLE GOING MUCH OF THIS TIME...DEPENDING ON SURFACE TEMPS.
SPEAKING OF WHICH...CONFIDENCE IS BELOW AVERAGE REGARDING WED HIGH
TEMPS DEPENDING ON THE BATTLE OF SOUTHERLY WARM AIR ADVECTION
VERSUS CLOUD COVER...BUT IF ANYTHING NUDGED HIGHS DOWN 1-2 DEGREES
FROM PREVIOUS WITH MID-UPPER 30S IN MOST NEB ZONES.
THURSDAY-THURSDAY NIGHT: SEE NUMBER "2" ABOVE FOR VARIOUS COMMENTS
ON THIS POSSIBLE SNOW EVENT...BUT IT WOULD GET UNDERWAY DURING
THIS TIME FRAME AS THE NEXT BATCH OF MID-UPPER FORCING ARRIVES
FROM THE SOUTHWEST...ALTHOUGH NOT IN AN OVERLY-ORGANIZED FASHION.
LATER FORECASTS MAY HAVE TO CONSIDER EXTENDING DRIZZLE/FREEZING
DRIZZLE POTENTIAL INTO AT LEAST THURSDAY DAYTIME BEFORE STEADIER
SNOW AND/OR RAIN BECOMES THE MORE DOMINANT TYPE. HAVE LOW END
"LIKELY" 60 PERCENT PRECIP CHANCES ACROSS MOST OF THE CWA FOR
THURSDAY NIGHT.
FRIDAY-FRIDAY NIGHT: ALTHOUGH ITS POSSIBLE THAT A LITTLE RAIN
POTENTIAL COULD STILL BE PRESENT BY SUNRISE FRIDAY IN FAR
SOUTHEAST ZONES...DEEPENING COLD AIR BEHIND A PASSING SURFACE COLD
FRONT SHOULD TRANSITION PRECIP TYPE TO SNOW ACROSS THE ENTIRE AREA
IF IT HASN`T ALREADY. WHILE SOME MODELS SUCH AS THE GFS PRETTY
MUCH SHUT DOWN ACCUMULATING SNOW BY FRIDAY NIGHT...OTHERS SUCH AS
THE ECMWF KEEP IT GOING.
SATURDAY DAYTIME-MONDAY DAYTIME: NOTHING MORE TO SAY HERE OTHER
THAN WHAT WAS ALREADY COVERED IN NUMBER "3" EARLIER ON: CONFIDENCE
IS REASONABLY HIGH IN A MAINLY SNOW-FREE STRETCH OF WEATHER WITH
THE ONLY REAL QUESTION SURROUNDING HOW COLD IT ACTUALLY GETS.
&&
.AVIATION...(FOR THE 00Z KGRI/KEAR TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 544 PM CST MON JAN 4 2016
FOG AND LOW CEILINGS ARE STILL A CONCERN FOR TONIGHT AND TUESDAY.
STRATUS IS EXPECTED TO SPREAD EASTWARD TONIGHT. IFR TO LIFR
CONDITIONS WILL BE POSSIBLE. SOME PATCHY FOG IS ALSO EXPECTED
DURING THE EARLY MORNING HOURS. THERE IS STILL SOME UNCERTAINTY AS
TO HOW WIDESPREAD THE FOG WILL BE AND HOW DENSE IT WILL BE...TAFS
WILL BE UPDATED AS NECESSARY. LOW MVFR STRATUS IS EXPECTED TO TAKE
HOLD AND REMAIN ACROSS THE AREA THROUGH TUESDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...WESELY
LONG TERM...PFANNKUCH
AVIATION...BILLINGS WRIGHT
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1135 AM CST SUN JAN 3 2016
.UPDATE...
ISSUED AT 613 AM CST SUN JAN 3 2016
THE RAP MODEL FORECASTS THE BANK OF STRATUS ACROSS MN TO MOVE INTO
NCNTL NEB AS EARLY AS 19Z THIS AFTN. A NEW FORECAST IS IN PLACE
WHICH BRINGS THE STRATUS TO NEAR NORTH PLATTE LATE TONIGHT. FOG
MAY FORM ALSO TONIGHT AND LATER FORECASTS WILL ADDRESS THIS
FEATURE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CST SUN JAN 3 2016
H850 MB TEMPERATURES HAVE COOLED A FEW DEGREES
TO AROUND 1C AND WINDS AT THIS LEVEL DECREASE TO 5 TO 15 KT.
NORTHWEST WINDS TODAY AND TONIGHT ARE VERY LIGHT AS A 1034 MB HIGH
MOVES OVER CNTL NEB TOWARD OMAHA BY MONDAY MORNING. A BLEND OF THE
MAV AND ECS GUIDANCE PLUS BIAS CORRECTION PRODUCES HIGHS IN THE 30S
TO AROUND 40. THE MET GUIDANCE WAS SEVERAL DEGREES COOLER THAN THE
MAV AND ECS DATA.
CLEAR SKIES AND LIGHT NORTHWEST WINDS GENERALLY LESS THAN 10 MPH
CONTINUE TODAY AND TONIGHT AS THE HIGH PRESSURE MOVES OVERHEAD.
LOWS TONIGHT FALL INTO THE SINGLE DIGITS TO AROUND 12F. IT LOOKS
LIKE THE AIRMASS OVERHEAD WILL REMAIN VERY DRY WITH LIGHT WINDS.
LOWS WOULD LIKELY OCCUR BEFORE SOUTH WINDS DEVELOP AROUND MIDNIGHT
IN THE WEST AND 6 AM IN THE EAST.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 AM CST SUN JAN 3 2016
MID RANGE...MONDAY THROUGH TUESDAY NIGHT...RIDGING CENTERED ACROSS
THE CENTRAL CONUS...WILL BEGIN TO BREAK DOWN MONDAY WITH SWRLY FLOW
ALOFT DEVELOPING ACROSS THE CENTRAL PLAINS MONDAY NIGHT INTO TUESDAY
NIGHT. AT THE SURFACE...HIGH PRESSURE WILL BUILD SOUTH ALONG THE
MISSOURI RIVER FROM EASTERN NEBRASKA INTO NORTHERN MISSOURI ON
MONDAY INTO MONDAY NIGHT. WINDS WILL BE VERY LIGHT IN THE EAST FOR
MONDAY WHICH WILL LIMIT MIXING AS WELL AS HOLDING HIGHS BACK INTO
THE MIDDLE 30S. FURTHER WEST...A TIGHTENING PRESSURE GRADIENT...WILL
LEAD TO INCREASING SRLY WINDS BY MONDAY AFTERNOON. THIS WILL
FACILITATE BETTER MIXING WITH HIGHS REACHING THE LOWER 40S. ON
MONDAY NIGHT SRLY WINDS WILL CONTINUE TO INCREASE AS HIGH PRESSURE
MOVES INTO EASTERN MO...AND A SURFACE TROUGH OF LOW PRESSURE DEEPENS
OFF TO THE WEST IN EASTERN WYOMING AND ERN COLORADO. WITH WINDS NOT
EXPECTED TO TOTALLY DECOUPLE OVERNIGHT...LOWS WILL BE MILD WITH
READINGS IN THE UPPER TEENS TO AROUND 20 DEGREES. CLOUDS WERE
INCREASED AS WELL IN THE WEST AND CENTRAL CWA MONDAY NIGHT AS THE
NAM AND GFS SOLNS INDICATE A NICE PLUME OF H850 TO H900 MOISTURE
PUSHING INTO AREA FROM THE SOUTH. WAS A TAD CONCERNED ABOUT FREEZING
DRIZZLE POTENTIAL PER BUFKIT SOUNDINGS...BUT WILL HOLD OFF MENTION
FOR NOW AS LIFT IN THE MOIST LAYER APPEARS WEAK AT THIS TIME. ON
TUESDAY...A LEAD WAVE LIFT ACROSS SRN COLORADO INTO WESTERN KANSAS
AND SWRN NEBRASKA. LOW LEVEL MOISTURE...PRESENT ACROSS THE WESTERN
AND CENTRAL CWA...WILL TRANSITION EAST DURING THE DAY...BECOMING
FOCUSED OVER EASTERN NEBRASKA BY WEDNESDAY MORNING. MID LEVEL
MOISTURE WILL BE VERY LIMITED ACROSS THE FORECAST AREA ON
TUESDAY...SO NOT EXPECTING ANY PRECIPITATION AT THIS TIME. HIGHS ON
TUESDAY WILL BE IN THE UPPER 30S TO LOWER 40S...HOWEVER THESE
READINGS MAY BE A LITTLE TOO OPTIMISTIC IF LOW CLOUDINESS PERSISTS
INTO THE AFTERNOON HOURS.
LONG RANGE...WEDNESDAY THROUGH SATURDAY...FOR THE LONG TERM...THE
MAIN FORECAST CHALLENGE IS THE POTENTIAL FOR PRECIPITATION
THURSDAY INTO FRIDAY. THE GFS AND ECMWF SOLNS CONTINUE TO DEVELOP
A CLOSED LOW OVER EASTERN COLORADO WEDNESDAY NIGHT...LIFTING THIS
FEATURE INTO WESTERN KANSAS THURSDAY...THEN EASTERN NEBRASKA
OVERNIGHT THURSDAY NIGHT INTO FRIDAY. A LEAD DISTURBANCE WILL
SPREAD LIGHT PRECIPITATION TO WESTERN NEBRASKA THURSDAY
MORNING...FOLLOWED BY A MORE SUSTAINED PRECIPITATION EVENT
THURSDAY NIGHT/FRIDAY AS THE MAIN UPPER LEVEL LOW TRACKS ACROSS KS
INTO EASTERN NEBRASKA. SNOW IS EXPECTED WITH THE MAIN UPPER LEVEL
LOW...HOWEVER THERE IS SOME UNCERTAINTY AS TO PTYPE WITH THE
INITIAL WAVE ON THURSDAY. BOTH THE ECMWF AND GFS SOLNS PUSH A
TONGUE OF WARM AIR INTO SOUTHWESTERN...THEN PORTIONS OF CENTRAL
NEBRASKA THURSDAY MORNING. FOR NOW...WILL MENTION RAIN OR SNOW IN
THE SOUTHWEST AND CENTRAL CWA THURSDAY PER BUFKIT SOUNDINGS WITH
ALL SNOW EXPECTED THURSDAY NIGHT THROUGH FRIDAY. AS FOR THE THREAT
FOR FREEZING DRIZZLE...THE ECMWF SOLN HAS A NICE MID LEVEL MOIST
LAYER THURSDAY WHICH WOULD LIMIT THE FZDZ THREAT. THE GFS DOES
PUSH A BRIEF MID LEVEL DRY LAYER INTO THE CWA THURSDAY
AFTERNOON...BETWEEN DISTURBANCES WHICH WOULD BE MORE FAVORABLE FOR
FZDZ. GIVEN THE MODEL DIFFERENCES ATTM...WILL FORGO A MENTION OF
FZDZ AT THIS TIME. THE UPPER LEVEL SYSTEM WILL EXIT THE AREA ON
FRIDAY NIGHT. IN ITS WAKE...MUCH COLDER AIR WILL PUSH INTO WESTERN
AND NORTH CENTRAL NEBRASKA FOR SATURDAY WITH H85 TEMPS SAT MORNING
RANGING FROM MINUS 12 TO MINUS 14C.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1135 AM CST SUN JAN 3 2016
VFR CONDITIONS AND WINDS UNDER 10 KTS WILL CONTINUE THROUGH THIS
EVENING ACROSS WESTERN NEBRASKA. TONIGHT...A COLD FRONT BACKS INTO
NORTH CENTRAL NEBRASKA...LOWERING CIGS DUE TO STRATUS. ON THE
WESTERN EDGE OF THE STRATUS...FOG WILL LIKELY FORM. HIGHEST
CONFIDENCE OF MVFR OR IFR IS GENERALLY NEAR KONL AND
EAST...HOWEVER SOME PATCHY FOG MAY WORK AS FAR WEST AS KLBF TO
KTIF TO KANW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...BUTTLER
AVIATION...SNIVELY
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
615 AM CST SUN JAN 3 2016
.UPDATE...
ISSUED AT 613 AM CST SUN JAN 3 2016
THE RAP MODEL FORECASTS THE BANK OF STRATUS ACROSS MN TO MOVE INTO
NCNTL NEB AS EARLY AS 19Z THIS AFTN. A NEW FORECAST IS IN PLACE
WHICH BRINGS THE STRATUS TO NEAR NORTH PLATTE LATE TONIGHT. FOG
MAY FORM ALSO TONIGHT AND LATER FORECASTS WILL ADDRESS THIS
FEATURE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CST SUN JAN 3 2016
H850 MB TEMPERATURES HAVE COOLED A FEW DEGREES
TO AROUND 1C AND WINDS AT THIS LEVEL DECREASE TO 5 TO 15 KT.
NORTHWEST WINDS TODAY AND TONIGHT ARE VERY LIGHT AS A 1034 MB HIGH
MOVES OVER CNTL NEB TOWARD OMAHA BY MONDAY MORNING. A BLEND OF THE
MAV AND ECS GUIDANCE PLUS BIAS CORRECTION PRODUCES HIGHS IN THE 30S
TO AROUND 40. THE MET GUIDANCE WAS SEVERAL DEGREES COOLER THAN THE
MAV AND ECS DATA.
CLEAR SKIES AND LIGHT NORTHWEST WINDS GENERALLY LESS THAN 10 MPH
CONTINUE TODAY AND TONIGHT AS THE HIGH PRESSURE MOVES OVERHEAD.
LOWS TONIGHT FALL INTO THE SINGLE DIGITS TO AROUND 12F. IT LOOKS
LIKE THE AIRMASS OVERHEAD WILL REMAIN VERY DRY WITH LIGHT WINDS.
LOWS WOULD LIKELY OCCUR BEFORE SOUTH WINDS DEVELOP AROUND MIDNIGHT
IN THE WEST AND 6 AM IN THE EAST.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 AM CST SUN JAN 3 2016
MID RANGE...MONDAY THROUGH TUESDAY NIGHT...RIDGING CENTERED ACROSS
THE CENTRAL CONUS...WILL BEGIN TO BREAK DOWN MONDAY WITH SWRLY FLOW
ALOFT DEVELOPING ACROSS THE CENTRAL PLAINS MONDAY NIGHT INTO TUESDAY
NIGHT. AT THE SURFACE...HIGH PRESSURE WILL BUILD SOUTH ALONG THE
MISSOURI RIVER FROM EASTERN NEBRASKA INTO NORTHERN MISSOURI ON
MONDAY INTO MONDAY NIGHT. WINDS WILL BE VERY LIGHT IN THE EAST FOR
MONDAY WHICH WILL LIMIT MIXING AS WELL AS HOLDING HIGHS BACK INTO
THE MIDDLE 30S. FURTHER WEST...A TIGHTENING PRESSURE GRADIENT...WILL
LEAD TO INCREASING SRLY WINDS BY MONDAY AFTERNOON. THIS WILL
FACILITATE BETTER MIXING WITH HIGHS REACHING THE LOWER 40S. ON
MONDAY NIGHT SRLY WINDS WILL CONTINUE TO INCREASE AS HIGH PRESSURE
MOVES INTO EASTERN MO...AND A SURFACE TROUGH OF LOW PRESSURE DEEPENS
OFF TO THE WEST IN EASTERN WYOMING AND ERN COLORADO. WITH WINDS NOT
EXPECTED TO TOTALLY DECOUPLE OVERNIGHT...LOWS WILL BE MILD WITH
READINGS IN THE UPPER TEENS TO AROUND 20 DEGREES. CLOUDS WERE
INCREASED AS WELL IN THE WEST AND CENTRAL CWA MONDAY NIGHT AS THE
NAM AND GFS SOLNS INDICATE A NICE PLUME OF H850 TO H900 MOISTURE
PUSHING INTO AREA FROM THE SOUTH. WAS A TAD CONCERNED ABOUT FREEZING
DRIZZLE POTENTIAL PER BUFKIT SOUNDINGS...BUT WILL HOLD OFF MENTION
FOR NOW AS LIFT IN THE MOIST LAYER APPEARS WEAK AT THIS TIME. ON
TUESDAY...A LEAD WAVE LIFT ACROSS SRN COLORADO INTO WESTERN KANSAS
AND SWRN NEBRASKA. LOW LEVEL MOISTURE...PRESENT ACROSS THE WESTERN
AND CENTRAL CWA...WILL TRANSITION EAST DURING THE DAY...BECOMING
FOCUSED OVER EASTERN NEBRASKA BY WEDNESDAY MORNING. MID LEVEL
MOISTURE WILL BE VERY LIMITED ACROSS THE FORECAST AREA ON
TUESDAY...SO NOT EXPECTING ANY PRECIPITATION AT THIS TIME. HIGHS ON
TUESDAY WILL BE IN THE UPPER 30S TO LOWER 40S...HOWEVER THESE
READINGS MAY BE A LITTLE TOO OPTIMISTIC IF LOW CLOUDINESS PERSISTS
INTO THE AFTERNOON HOURS.
LONG RANGE...WEDNESDAY THROUGH SATURDAY...FOR THE LONG TERM...THE
MAIN FORECAST CHALLENGE IS THE POTENTIAL FOR PRECIPITATION
THURSDAY INTO FRIDAY. THE GFS AND ECMWF SOLNS CONTINUE TO DEVELOP
A CLOSED LOW OVER EASTERN COLORADO WEDNESDAY NIGHT...LIFTING THIS
FEATURE INTO WESTERN KANSAS THURSDAY...THEN EASTERN NEBRASKA
OVERNIGHT THURSDAY NIGHT INTO FRIDAY. A LEAD DISTURBANCE WILL
SPREAD LIGHT PRECIPITATION TO WESTERN NEBRASKA THURSDAY
MORNING...FOLLOWED BY A MORE SUSTAINED PRECIPITATION EVENT
THURSDAY NIGHT/FRIDAY AS THE MAIN UPPER LEVEL LOW TRACKS ACROSS KS
INTO EASTERN NEBRASKA. SNOW IS EXPECTED WITH THE MAIN UPPER LEVEL
LOW...HOWEVER THERE IS SOME UNCERTAINTY AS TO PTYPE WITH THE
INITIAL WAVE ON THURSDAY. BOTH THE ECMWF AND GFS SOLNS PUSH A
TONGUE OF WARM AIR INTO SOUTHWESTERN...THEN PORTIONS OF CENTRAL
NEBRASKA THURSDAY MORNING. FOR NOW...WILL MENTION RAIN OR SNOW IN
THE SOUTHWEST AND CENTRAL CWA THURSDAY PER BUFKIT SOUNDINGS WITH
ALL SNOW EXPECTED THURSDAY NIGHT THROUGH FRIDAY. AS FOR THE THREAT
FOR FREEZING DRIZZLE...THE ECMWF SOLN HAS A NICE MID LEVEL MOIST
LAYER THURSDAY WHICH WOULD LIMIT THE FZDZ THREAT. THE GFS DOES
PUSH A BRIEF MID LEVEL DRY LAYER INTO THE CWA THURSDAY
AFTERNOON...BETWEEN DISTURBANCES WHICH WOULD BE MORE FAVORABLE FOR
FZDZ. GIVEN THE MODEL DIFFERENCES ATTM...WILL FORGO A MENTION OF
FZDZ AT THIS TIME. THE UPPER LEVEL SYSTEM WILL EXIT THE AREA ON
FRIDAY NIGHT. IN ITS WAKE...MUCH COLDER AIR WILL PUSH INTO WESTERN
AND NORTH CENTRAL NEBRASKA FOR SATURDAY WITH H85 TEMPS SAT MORNING
RANGING FROM MINUS 12 TO MINUS 14C.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 535 AM CST SUN JAN 3 2016
THE AREA OF IFR CIGS ACROSS THE UPPER MIDWEST IS FCST TO MOVE
WEST THIS MORNING BY THE RAP MODEL AND REACH HIGHWAY 183 THIS
EVENING. THEREAFTER...THE NAM AND SREF SUGGEST THIS CLOUD AREA
WILL REMAIN STATIONARY. THESE SOLNS...INCLUDING THE RAP...INDICATE
FOG MAY FORM TONIGHT EAST OF HIGHWAY 83. VFR IS EXPECTED
ELSEWHERE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CDC
SHORT TERM...CDC
LONG TERM...BUTTLER
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1138 PM CST SAT JAN 2 2016
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 315 PM CST SAT JAN 2 2016
THE PRIMARY FORECAST CONCERNS INCLUDE THE POTENTIAL FOR LOW CLOUDS
LATE TONIGHT INTO SUNDAY AND TEMPERATURES THE NEXT FEW DAYS.
PATTERN ALOFT HAD NOT CHANGED A LOT COMPARED TO YESTERDAY. REX
BLOCK STILL REMAINED TO OUR WEST/NORTHWEST...WITH FAIRLY FAST
FLOW AT 500 MB FROM SASKATCHEWAN AND MANITOBA INTO THE GREAT LAKES
REGION. 850 MB TEMPERATURES HAD WARMED A BIT FROM MONTANA AND
WESTERN NORTH DAKOTA SOUTHEASTWARD INTO OUR AREA. SURFACE ANALYSIS
SHOWED LOW PRESSURE CENTERED NORTHEAST OF LAKE SUPERIOR WITH HIGH
PRESSURE LOCATED TO OUR WEST AND SOUTH. SURFACE WINDS VARIED FROM
SOUTHWEST TO NORTHWEST IN OUR FORECAST AREA.
SATELLITE IMAGERY LOOP SHOWED LOW CLOUDS TO OUR NORTH...DROPPING
DOWN INTO NORTHERN MINNESOTA AND THE FAR NORTHEAST CORNER OF NORTH
DAKOTA. LOOKING AT SOME OF THE SHORT RANGE HIGH RESOLUTION MODELS...
INCLUDING THE 18Z EXPERIMENTAL HRRR...BELIEVE LOW CLOUDS COULD
APPROACH THE NORTHERN PARTS OF THE FORECAST AREA BY 12Z. THE
PREVIOUSLY MENTIONED HRRR THEN BRINGS THESE SOUTH TO OMAHA AND
MUCH OF WESTERN IOWA BY MID TO LATE MORNING. THE GFS AND NAM SHOW
VARYING DEGREES OF LOWER TROPOSPHERIC RELATIVE HUMIDITY VALUES
(AREA AROUND 925 MB SEEMED TO BE BEST LEVEL TO LOOK AT) SO THE
AMOUNT OF CLOUD COVER FOR SUNDAY IS IN QUESTION. WILL COUNT ON
SKIES AT LEAST BECOMING PARTLY CLOUDY FOR NOW.
HIGH PRESSURE AT THE SURFACE WILL SETTLE DOWN ACROSS EASTERN
NEBRASKA AND SOUTHWEST IOWA FOR LATE SUNDAY NIGHT/EARLY MONDAY
MORNING. THINK THERE WILL BE AT LEAST PATCHY FOG WITH LIGHT WINDS.
RETURN FLOW STRENGTHENS MONDAY AND INTO MONDAY NIGHT/TUESDAY. AT
SOME POINT...LOW CLOUDS MAY RETURN...POSSIBLY BY TUESDAY NIGHT.
OVERALL THE NAM MOS TEMPERATURES SEEMED TOO COOL. USED A BLEND...
WITH A DECENT AMOUNT OF WEIGHT GIVEN TO GFS AND ECMWF...ESPECIALLY
FOR HIGHS.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 315 PM CST SAT JAN 2 2016
THIS PERIOD WILL GET MORE ACTIVE...ESPECIALLY BY THURSDAY. WILL
INCLUDE SOME LOW POPS PRIOR TO THAT...BUT IT MAY END UP BEING MORE
TRACE TYPE PCPN...DRIZZLE/FREEZING DRIZZLE/FLURRIES. LARGE SCALE
FORCING REMAINS WEAK TUESDAY NIGHT INTO WEDNESDAY NIGHT. DEEPER
MOISTURE AND BETTER LARGE SCALE LIFT ARE IN PLACE FROM LATE
THURSDAY INTO EARLY SATURDAY...BUT NOT CONTINUOUSLY. AFTER THAT...
IT APPEARS WE WILL TURN COLDER...AS CANADIAN AIR IS FILTERED DOWN
INTO THE NORTHERN AND CENTRAL PLAINS.
PCPN TYPE WILL LIKELY BE MIXED THURSDAY INTO FRIDAY...THEN MAINLY
JUST LIGHT SNOW BY FRIDAY NIGHT/SATURDAY. WILL REFINE THIS MORE AS
THE EVENT APPROACHES. SOME SNOW ACCUMULATIONS SEEM POSSIBLE.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1133 PM CST SAT JAN 2 2016
AREA OF LOW CLOUDS LOCATED OVER SOUTHERN MINNESOTA AND EASTERN
SOUTH DAKOTA AT THE START OF THE PERIOD IS EXPECTED TO CONTINUE TO
DROP SOUTH THROUGH 12Z. MVFR CIGS ARE EXPECTED TO REACH THE TAF
SITES BETWEEN 12Z AND 15Z THEN HANG ON INTO SUNDAY AFTERNOON WITH
MVFR VSBY ALSO POSSIBLE. MVFR CONDITIONS THEN LINGER PAST 00Z WITH
FOG BECOMING MORE LIKELY AND VSBYS DECREASING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
251 PM MST SUN JAN 3 2016
.SYNOPSIS...
ACTIVE WEEK OF WEATHER ON THE WAY. FOUR UPPER LEVEL DISTURBANCES TO
IMPACT NM OVER THE NEXT SEVEN DAYS. FIRST TROUGH WILL SWING THROUGH
MONDAY NIGHT INTO TUESDAY...SECOND ON WEDNESDAY...THIRD ON THURSDAY
AND THE FOURTH FRIDAY NIGHT. EACH WILL BE FAIRLY FAST MOVING BUT
ABLE TO PRODUCE LIGHT TO MODERATE AMOUNTS OF PRECIPITATION. EACH
SYSTEM WILL BRING A MIX OF RAIN AND SNOW WITH A GENERAL TREND
TOWARD COOLER TEMPERATURES BY LATE IN THE WEEK.
&&
.DISCUSSION...
LAND OF ENCHANTMENT ENJOYING ITS MILDEST TEMPERATURES SINCE
AROUND CHRISTMAS FOR MUCH OF NORTHERN AND CENTRAL NM. LOTS OF
SUNSHINE AND LIGHT WINDS HELPING IT FEEL PRETTY GOOD FOR AN EARLY
JANUARY DAY. SNOW COVER STILL IMPACTING SOME PLACES THOUGH WHERE
IT CONTINUES CHILLY...LIKE ROSWELL AT 41 AND CLINES CORNERS AT 35.
A QUIET NIGHT TONIGHT WILL BE FOLLOWED BY INCREASING CLOUDS AND
PRECIPITATION DEVELOPMENT FROM WEST TO EAST MONDAY. IT WILL BE
MILD ENOUGH FOR RAIN AT LOWER ELEVATIONS WHILE SNOW IS STILL
FAVORED IN THE MOUNTAINS. BUT AT NIGHT MOSTLY SNOW WILL FALL.
FAVORED AREAS WILL BE THE WESTERN AND CENTRAL HIGH TERRAIN. WE
WILL HOIST A WINTER STORM WATCH FOR THE UPPER GILA REGION OF THE
SW MOUNTAINS WHERE HIGHEST QPF EXPECTED. COORDINATED WITH EPZ.
PRECIPITATION WILL DIMINISH DURING THE DAY TUESDAY AS THE FIRST
TROUGH LIFTS NE.
DISTURBANCE NUMBER TWO WILL CROSS WEDNESDAY AND BE QUICKLY
FOLLOWED BY A WEAK TROUGH ON THURSDAY. MAY BE HARD TO DISTINGUISH
A BREAK BETWEEN THEM. WESTERN AND NORTHERN AREAS WILL BE FAVORED.
FOURTH SYSTEM FRIDAY INTO SATURDAY WILL BRING MOSTLY SNOW WITH
WESTERN AREAS FAVORED.
WHILE EACH TROUGH WILL NOT BRING COPIOUS AMOUNTS OF PRECIPITATION
DUE TO THEIR PROGRESSIVE NATURE...SIGNIFICANT SNOW ACCUMULATIONS
WILL BE POSSIBLE IN AREAS THAT ARE IMPACT BY ALL FOUR EVENTS. AS
OF NOW THAT WOULD BE OVER THE CENTRAL AND ESPECIALLY WESTERN
MOUNTAINS. CHJ
&&
.FIRE WEATHER...
TODAY WILL BE THE LAST DAY OF SUNSHINE AND RELATIVELY WARM
TEMPERATURES BEFORE A SERIES OF UPPER LEVEL DISTURBANCES PLAGUE THE
LAND OF ENCHANTMENT DURING THE WORK WEEK. IN SHORT...LOOK FOR
WETTING PRECIP...HIGH HUMIDITIES AND POOR VENTILATION FOR MUCH OF
THE PERIOD.
THE FIRST IN A SERIES OF SYSTEMS WILL ARRIVE TOMORROW AFTERNOON AND
SWEEP ACROSS THE STATE TOMORROW NIGHT INTO TUESDAY. THOUGH PRECIP AT
LOWER ELEVATIONS...BELOW 6500 FEET...MAY BEGIN AS RAIN...
TEMPERATURES SHOULD BE COLD ENOUGH FOR SNOW AT ALL LOCATIONS BY LATE
MONDAY NIGHT. MODELS ARE SUGGESTING THAT THE WEST CENTRAL HIGHLANDS
WILL SEE THE GREATEST SNOW AMOUNTS...THOUGH LIGHT AMOUNTS MAY SPREAD
ACROSS MUCH OF WESTERN AND CENTRAL NM. SOME MODELS ARE ALSO
SUGGESTING A BAND OF SNOW WILL DEVELOP ACROSS THE EAST CENTRAL
PLAINS EARLY TUESDAY. WILL WAIT TO SEE IF MODELS COME INTO BETTER
AGREEMENT ON THIS FEATURE.
THE 2ND TROUGH WILL IMPACT NM WEDNESDAY AND WED NIGHT AND LOOKS TO
FAVOR WESTERN AND CENTRAL NM FOR PRECIP...ESPECIALLY THE NW QUARTER
OF THE STATE. MID LEVEL TEMPS DO NOT DROP TOO MUCH FROM THE FIRST
TROUGH SO COULD STILL SEE SOME RAIN MIX IN AT LOWER ELEVATIONS WED
AFTN. WINDS WILL PICK UP BEHIND A PACIFIC FRONT ACROSS THE
WEST...ALLOWING FOR VENT RATES TO IMPROVE SOMEWHAT ALONG AND WEST OF
THE CONTINENTAL DIVIDE.
LOOKS LIKE ANOTHER TROUGH...THIS ONE A BIT COLDER...WILL SWING THRU
ON THURSDAY. PRECIP WILL AGAIN FAVOR CENTRAL AND WESTERN NM.
MEANWHILE...A SURFACE LOW OVER NE NM COMBINED WITH STRONGER MID
LEVEL WINDS AND SOMEWHAT IMPROVED MIXING HEIGHTS MAY INCREASE WINDS
INTO THE BREEZY OR EVEN WINDY CATEGORY ACROSS THE PLAINS.
VENTILATION RATES LOOK TO BE GOOD OR BETTER NEAR AND SOUTH OF I-40.
MUCH COLDER AIR FILTERS IN BEHIND THE 3RD SYSTEM...THUS PRECIP FROM
THE 4TH SHOULD BE MAINLY SNOW. THE 4TH TROUGH LOOKS TO HAVE A
GREATER IMPACT ON SOUTHERN NM AS IT TAKES A MUCH MORE SOUTHERLY
TRACK THAN THE PREVIOUS THREE. THIS ONE SHOULD IMPACTS AREAS
GENERALLY SOUTH OF I-40 STARTING FRIDAY AND CONTINUING THRU EARLY
SATURDAY.
THOUGH EACH STORM SYSTEM WILL BE QUICK-HITTING...SNOW FROM ALL FOUR
SYSTEMS MAY ADD UP TO BE SIGNIFICANT AMOUNTS. LOOK FOR CONTINUED
CHANGES AS MODELS CONTINUE TO STRUGGLE WITH THE STRENGTH...DEPTH AND
TIMING OF THESE SYSTEMS DUE TO THEIR RAPID SUCCESSION. CONFIDENCE IS
HIGH... HOWEVER...THAT TEMPERATURES WILL REMAIN BELOW NORMAL THRU
THE PERIOD AND THAT MANY AREAS WILL SEE WETTING PRECIP. 34
&&
.AVIATION...
18Z TAF CYCLE
VFR CONDITIONS SHOULD PREVAIL THROUGH THE DAYTIME HOURS ACROSS
THE AREA. MID AND HIGH CLOUDS SHOULD SLOWLY INCREASE FROM WEST
TO EAST. SUSPECT THAT KROW WILL HAVE LIFR CIGS AND VSBYS AGAIN
TONIGHT...BUT WHEN AND FOR HOW LONG REMAINS QUESTIONABLE. LOW
CIGS AND VSBYS ARE ALSO POSSIBLE AROUND K0E0 TONIGHT BASED ON
LATEST HRRR PROGS. 34
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 18 40 26 40 / 0 20 60 30
DULCE........................... 5 39 20 39 / 0 20 40 40
CUBA............................ 15 37 22 37 / 0 10 40 40
GALLUP.......................... 17 42 25 41 / 5 30 40 30
EL MORRO........................ 14 39 23 38 / 5 20 70 30
GRANTS.......................... 14 39 21 40 / 0 20 30 20
QUEMADO......................... 22 42 28 40 / 5 30 30 30
GLENWOOD........................ 24 48 30 46 / 5 40 60 40
CHAMA........................... 7 36 18 35 / 0 20 50 40
LOS ALAMOS...................... 18 36 24 36 / 0 5 50 40
PECOS........................... 14 35 21 35 / 0 0 30 40
CERRO/QUESTA.................... 1 35 16 35 / 0 0 20 20
RED RIVER....................... 2 31 16 30 / 0 0 30 20
ANGEL FIRE...................... -2 34 12 33 / 0 0 20 20
TAOS............................ 4 37 17 37 / 0 0 20 20
MORA............................ 13 37 19 36 / 0 0 20 20
ESPANOLA........................ 15 41 23 41 / 0 0 30 30
SANTA FE........................ 17 36 24 35 / 0 0 40 30
SANTA FE AIRPORT................ 16 37 22 37 / 0 5 40 30
ALBUQUERQUE FOOTHILLS........... 21 39 27 39 / 0 10 40 30
ALBUQUERQUE HEIGHTS............. 21 40 27 41 / 0 5 40 20
ALBUQUERQUE VALLEY.............. 19 41 28 42 / 0 10 40 20
ALBUQUERQUE WEST MESA........... 21 42 27 42 / 0 10 30 20
LOS LUNAS....................... 20 41 26 42 / 0 10 50 20
RIO RANCHO...................... 21 41 27 41 / 0 10 30 30
SOCORRO......................... 21 40 28 42 / 0 10 50 20
SANDIA PARK/CEDAR CREST......... 18 35 23 36 / 0 10 40 30
TIJERAS......................... 18 37 25 37 / 0 10 40 30
MORIARTY/ESTANCIA............... 8 35 17 38 / 0 5 50 20
CLINES CORNERS.................. 13 34 19 33 / 0 5 50 30
GRAN QUIVIRA.................... 16 35 23 36 / 0 10 50 30
CARRIZOZO....................... 20 41 25 40 / 0 10 40 30
RUIDOSO......................... 21 37 25 36 / 0 10 60 40
CAPULIN......................... 13 37 21 38 / 0 0 10 10
RATON........................... 12 41 18 43 / 0 0 10 10
SPRINGER........................ 13 40 17 40 / 0 0 20 10
LAS VEGAS....................... 14 36 19 38 / 0 0 40 20
CLAYTON......................... 20 42 24 41 / 0 0 5 5
ROY............................. 15 37 20 36 / 0 0 20 10
CONCHAS......................... 19 41 25 40 / 0 0 40 20
SANTA ROSA...................... 17 39 24 38 / 0 0 50 30
TUCUMCARI....................... 15 41 24 41 / 0 0 30 20
CLOVIS.......................... 19 40 23 37 / 0 0 30 30
PORTALES........................ 20 41 25 38 / 0 0 30 30
FORT SUMNER..................... 18 40 25 38 / 0 0 40 30
ROSWELL......................... 17 38 25 40 / 0 0 30 30
PICACHO......................... 18 37 24 37 / 0 5 40 40
ELK............................. 22 36 25 38 / 0 10 50 50
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY AFTERNOON
FOR THE FOLLOWING ZONES... NMZ508.
&&
$$
40/34
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
312 PM EST SUN JAN 3 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL DROP THROUGH THE AREA LATE THIS
AFTERNOON AND EVENING...ACCOMPANIED BY SCATTERED TO WIDESPREAD
SNOW SHOWERS PRIMARILY ACROSS CENTRAL NEW YORK. THE FRONT WILL
BRING IN THE COLDEST AIR MASS SO FAR THIS SEASON TONIGHT THROUGH
MONDAY NIGHT. THIS WILL INCLUDE WIND CHILLS DROPPING TO AROUND OR
BELOW ZERO MONDAY. ALSO...SCATTERED SNOW SHOWERS AND FLURRIES WILL
LINGER MAINLY IN THE FINGER LAKES REGION TO CENTRAL TWIN TIERS.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
ARCTIC COLD FRONT IS REACHING THE SOUTH SHORE OF LAKE ONTARIO AS
OF 3 PM. TEMPERATURES NORTH OF THE LAKE HAVE FALLEN INTO THE UPPER
TEENS TO MID 20S AND THIS AIR MASS WILL OVERSPREAD CENTRAL NEW
YORK AND NORTHEAST PA LATER THIS EVENING. IN THE MEANTIME A BAND
OF SNOW SHOWERS HAS DEVELOPED JUST AHEAD OF THE FRONT TO THE EAST
OF LAKE ONTARIO. THIS BAND WILL MOVE SOUTH LINKING UP WITH THE
ARCTIC FRONT LATE THIS AFTERNOON AND EARLY THIS EVENING... HOWEVER
IT IS EXPECTED TO WEAKEN AS IT LOOSES ITS FAVORABLE FETCH OFF OF
LAKE ONTARIO AS IT MOVES SOUTH OF SYRACUSE EARLY THIS EVENING. AS
A RESULT WE ARE EXPECTING A QUICK 1 TO 3 INCHES IN THE SYRACUSE
AND ROME AREAS WITH THE PASSAGE OF THIS BAND THROUGH EARLY THIS
EVENING... BUT ONLY AN INCH OR SO IN THE ITHACA AND CORTLAND
AREAS... AND LESS THAN AN INCH FARTHER SOUTH.
THE FLOW WILL SHIFT TO NORTHWEST BEHIND THE ARCTIC FRONT THIS
EVENING WITH A PERIOD OF MULTI-BAND LAKE EFFECT SNOW EXPECTED
AFFECTING THE AREA FROM SYR DOWN TO NEAR ITH AND BGM. MUCH OF THIS
AREA CAN EXPECT ANOTHER INCH OR TWO WITH A LITTLE LESS DOWN TOWARD
THE NY/PA BORDER. AFTER MIDNIGHT THE FLOW WILL SHIFT TO AROUND
330-340 DEGREES WHICH WILL FOCUS THE LAKE EFFECT SNOW SHOWERS
WEST OF I-81 MAINLY OVER AND SOUTH OF THE FINGER LAKES.
BASED ON THIS SCENARIO WE ARE EXPECTING THE SYR TO ROME AREA TO
PICK UP AROUND 2 TO 4 INCHES OF SNOW FROM LATE THIS AFTERNOON
THROUGH TONIGHT... 1 TO 3 INCHES FROM CORTLAND TO ITHACA... AND
AROUND AN INCH AT ELM AND BGM. THESE TOTALS ARE ALL BELOW ADVISORY
THRESHOLDS BUT MOTORISTS SHOULD BE AWARE THAT THERE WILL BE
LOCALIZED SLICK TRAVEL... ESPECIALLY LATE THIS AFTERNOON WITH THE
SQUALL FROM SYR TO ROME.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
THE FLOW STARTS OUT MONDAY MORNING FROM 330 TO 345 DEGREES WHICH
WILL FAVOR SNOW SHOWERS SOUTH-SOUTHEAST OF THE FINGER LAKES. THE
DEEPEST MOISTURE AND DENDRITIC SNOW GROWTH PROFILES ARE IN THE
MORNING. IN THE AFTERNOON THE FLOW GOES TO 340-350 WITH SNOW
SHOWERS CONTINUING TO SHIFT SLIGHTLY WESTWARD TO INCLUDE AREAS
SOUTH OF SENACA LAKE. HOWEVER BY MONDAY AFTERNOON THE MOISTURE
WILL BE DECREASING AND DIURNAL EFFECTS WILL RESULT IN A LITTLE
LESS ORGANIZATION. OVERALL WE ARE EXPECTING AROUND 2 TO 4 INCHES
OF SNOW SOUTH-SOUTHEAST OF THE FINGER LAKES FROM LATE TONIGHT
THROUGH EARLY AFTERNOON MONDAY.
ELSEWHERE ON MONDAY THE MAIN WEATHER STORY WILL BE BY FAR THE
COLDEST AIRMASS THAT WE HAVE SEEN YET THIS WINTER. NNW FLOW WILL
BRING A DIRECT SHOT OF ARCTIC AIR DOWN INTO THE AREA WITH
TEMPERATURES DURING THE DAY MONDAY HOLDING IN THE TEENS. WITH
CLEARING AND DIMINISHING WINDS MONDAY NIGHT A FEW NORMALLY COLDER
LOCATIONS IN CENTRAL NEW YORK WILL PROBABLY NEAR TO JUST BELOW
ZERO... WITH SINGLE DIGITS ELSEWHERE.
THE WEATHER TURNS VERY QUIET ON TUESDAY AND WEDNESDAY WITH HIGH
PRESSURE DIRECTLY OVER THE AREA TUESDAY THEN SHIFTING OFF THE
COAST ON WEDNESDAY. THE RESULT WILL BE DRY SUNNY WEATHER WITH A
WARMING TREND... BACK INTO THE 20S ON TUESDAY AND THE 30S ON
WEDNESDAY.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
VISIBLE SATELLITE IMAGERY SHOWS WIDESPREAD CLOUDS ACROSS ALL WFO
BGM TERMINALS. CIGS WERE MAINLY MVFR-VFR RUNNING FROM ROUGHLY 2500
TO 3500 FEET AGL. THERE WERE A FEW SNOW SHOWERS AROUND BUT THE
MAIN BAND OF SNOW SHOWERS WAS EAST OF LAKE ONTARIO NORTH OF ONEIDA
CO. RAP13...NAM12 AND THE HRRR ALL PROJECT THIS BAND TO DROP
SOUTH REACHING SYR AND RME BTWN 18Z AND 21Z, AND 20-23Z ITH. THIS
SNOW BAND SHOULD BE LIFR IN SN AND CIGS. FARTHER SOUTH BY THE
TIME IT REACHES ELM AND BGM IT WILL WEAKEN SOME SO WE EXPECT IFR
IN SN AND CIG BOTH SITES. THE SNOW BAND IS NOT EXPECTED TO MAKE IT
ALL THE WAY TO KAVP. AFTER THIS BAND PASSES SOUTH, WINDS TURN
MORE NRLY AND THE FINGER LAKES REGION WILL SEE THE BULK OF A
MULTI-BAND LAKE EFFECT SNOWS WITH FINGER LAKES ENHANCEMENT. HAVE
LIFR AT ITH FROM 6Z ON THRU 18Z MON. HAVE ELM DOWN TO IFR
OVERNIGHT AND MON AM AS WELL. REST OF TAFS WILL IMPROVE TO VFR BY
MON AM.
WESTERLY WINDS AROUND 10-15 KNOTS WITH GUSTS OF 20 TO 25 KNOTS AT
TIMES WITH TURN NORTH TO NORTHWEST BY THIS EVENING WITH ROUGHLY
THE SAME SPEEDS THRU MON AM.
.OUTLOOK...
MONDAY PM-MON NIGHT...BRIEF RESTRICTIONS IN LAKE EFFECT SNOW
SHOWERS KITH-KELM.
TUESDAY THROUGH THURSDAY...VFR.
FRIDAY...POSSIBLE RESTRICTIONS IN RAIN SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MSE
NEAR TERM...MSE
SHORT TERM...MSE
LONG TERM...DJN
AVIATION...DJN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
151 PM EST SUN JAN 3 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL DROP THROUGH THE AREA THIS AFTERNOON
AND EVENING...ACCOMPANIED BY SCATTERED TO WIDESPREAD SNOW SHOWERS
PRIMARILY ACROSS CENTRAL NEW YORK. THE FRONT WILL ABRUPTLY BRING
IN THE COLDEST AIR MASS SO FAR THIS SEASON TONIGHT THROUGH MONDAY
NIGHT. THIS WILL INCLUDE WIND CHILLS DROPPING TO AROUND OR BELOW
ZERO MONDAY. ALSO...SCATTERED SNOW SHOWERS AND FLURRIES WILL
LINGER MAINLY IN THE FINGER LAKES REGION TO CENTRAL TWIN TIERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATED AT NOON... ARCTIC COLD FRONT IS CURRENTLY LOCATED ALONG
THE NORTH SHORE OF LAKE ONTARIO DROPPING SOUTH. MEANWHILE... A
LARGE AREA OF LIGHT SNOW HAS DEVELOPD ACROSS MUCH OF CENTRAL NEW
YORK EARLY THIS AFTERNOON AND A HEAVIER BAND OF SNOW HAS
INTENSIFIED EAST OF LAKE ONTARIO. EXPECT THIS BAND OF HEAVIER SNOW
TO SLOWLY DROP SOUTH AND WILL PROBABLY BECOME LINKED WITH THE
ARCTIC FRONT LATER THIS AFTERNOON AS IT DROPS SOUTH ACROSS CENTRAL
NY. EXPECT A QUICK 2 TO 4 INCHES OF SNOW WITH THIS BAND AS IT
DROPS SOUTH INTO THE SYRACUSE AREA EARLY THIS AFTERNOON... THEN
LESS THAN 2 INCHES AS IT LOOSES IT BEST CONNECTION WITH THE LAKE
LATER THIS AFTERNOON. TEMPERATURES THIS AFTERNOON WILL BE IN THE
MID 30S... BUT WILL DROP RAPIDLY LATER THIS AFTERNOON WITH THE
PASSAGE OF THE ARCTIC FRONT. HAVE MADE SOME TWEAKS TO OUR SNOWFALL
FORECASTS TO ACCOUNT FOR THESE EXPECTATIONS THIS AFTERNOON AND
HAVE ALSO RAISED SNOW AMOUNTS SOUTH-SOUTHEAST OF THE FINGER LAKES
FOR LATER TONIGHT INTO MONDAY WITH NNW FLOW EXPECTED. PREVIOUS
DISCUSSION IS BELOW.
245 AM UPDATE...
MAIN CONCERN IS THE STRONG ARCTIC FRONT WHICH WILL DROP THROUGH
THE REGION THIS AFTERNOON AND EVENING...ACCOMPANIED BY GUSTY SNOW
SHOWERS-BRIEF SQUALLS MAINLY IN CENTRAL NEW YORK. THIS WILL BE
FOLLOWED BY SETTING UP OF SOME LAKE EFFECT SNOW IN THE FINGER
LAKES REGION LATE TONIGHT AS THE COLDEST AIR MASS OF THE SEASON
RUSHES SOUTHWARD FROM CANADA.
AHEAD OF THE FRONT...THINGS ARE PRETTY QUIET CURRENTLY WITH PATCHY
MID TO HIGH CLOUDS AND TEMPERATURES HOLDING IN THE MID 20S TO
LOWER 30S. HOWEVER...LOW PRESSURE IS CROSSING THE ONTARIO-QUEBEC
BORDER...WITH THE ARCTIC FRONT NOW SLIDING DOWN OVER THE NORTHERN
GREAT LAKES REGION. AS THE LOW QUICKLY TRANSLATES TO NORTHERN
MAINE THIS AFTERNOON...THE ARCTIC FRONT WILL DROP OUT OF CANADA
INTO NEW YORK...THEN CONTINUE THROUGH NORTHERN PA THIS EVENING.
WITH THE ENHANCEMENT OF GREAT LAKES MOISTURE...THE FRONT WILL BE
ACCOMPANIED BY GUSTY SNOW SHOWERS. OVERALL AMOUNTS WILL NOT BE
VERY MUCH THROUGH THIS EVENING...FROM 1-2 INCHES IN CENTRAL NEW
YORK TO LESS THAN AN INCH IN THE TWIN TIERS...BUT THE MANNER IN
WHICH IT FALLS COULD BE SQUALLY IN NATURE IMMEDIATELY ALONG THE
FRONT.
WIND WILL QUICKLY VEER NW TO NNW TONIGHT...WHICH ALONG WITH STRONG
COLD AIR ADVECTION ACROSS A SHORTENING FETCH OF LAKE
ONTARIO...WILL TEND TO COMPRESS LAKE EFFECT SNOW SHOWERS TO MAINLY
THE FINGER LAKES REGION TO CENTRAL TWIN TIERS OVERNIGHT...WITH
JUST SCATTERED FLURRIES ELSEWHERE. SATURATED LAYER WILL BE QUITE
SHALLOW YET ALMOST ENTIRELY CONTAINED WITHIN DENDRITIC GROWTH
LAYER BY LATE TONIGHT...TO THE POINT THAT JUST ABOUT ANY CLOUD
LAYER WILL BE PRODUCING FLUFFY SNOWFLAKES. FLOW BY MONDAY MORNING
WILL BE FAVORABLE FOR FINGER LAKE BANDS ESPECIALLY CAYUGA-
SENECA...THE SOUTH SHORES OF WHICH COULD EASILY PICK UP A COUPLE
INCHES OR SO OF FLUFFY ACCUMULATION. FLOW IN GENERAL WILL BE
TRANSIENT AS IT BACKS IN DIRECTION...BUT FOR THE WINDOWS OF TIME
THINGS LINE UP...DECENT FINGER LAKE SNOW BANDS MAY OCCUR.
DAWN MONDAY WILL BE A RUDE AWAKENING TO ANYONE NOT PREPARED FOR
THE COLDEST AIR MASS SINCE LAST WINTER...WITH WIND CHILLS MAINLY IN
THE SINGLE DIGITS ABOVE OR BELOW ZERO /AND ACTUAL TEMPERATURES
MAINLY TEENS/.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
430 AM UPDATE...
COLDEST AIR MASS OF THE SEASON WILL PROVIDE A VERY RAW DAY TO
START THE WEEK...THOUGH IT WILL NOT STAY VERY LONG. WIND CHILLS
WILL ACTUALLY START TO DIVE BELOW ZERO DURING THE DAY MONDAY. I
HOPE YOU HAVE YOUR BEST WINTER WEATHER CLOTHING READY FOR
YOURSELF AND FOR THE KIDS AT THE BUS STOP.
HIGHS FOR MONDAY WILL ACTUALLY OCCUR AT MIDNIGHT TONIGHT...BECAUSE
STRONG COLD AIR ADVECTION WILL SEND 1000-500MB THICKNESS TO ONLY ABOUT
510 DECAMETERS BY MORNING...ALONG WITH 850MB TEMPERATURES IN THE
UPPER TEENS-LOW 20S BELOW ZERO CELSIUS. WE HAVE NOT HAD ANYTHING
LIKE THAT SINCE LATE LAST WINTER. LOW LEVEL FLOW WILL BE NNW TO N.
AIR MASS WILL BE VERY DRY...AND ARCTIC SUNSHINE CAN EVEN BE
EXPECTED TO BREAK OUT EAST OF I-81. TO THE WEST HOWEVER...SHALLOW
DECK OF CLOUDS STRETCHING FROM LAKE ONTARIO THROUGH THE FINGER
LAKES...INCLUDING CONTINUED LAKE EFFECT SNOW SHOWERS ESPECIALLY IN
THE MORNING. THOUGH THE SATURATED LAYER WILL BE SHALLOW...IT WILL
STILL BE ALMOST ENTIRELY AT DENDRITIC GROWTH TEMPERATURES...WHICH
WILL CONTINUE TO BE SUPPORTIVE OF VERY FLUFFY LOW WATER CONTENT
SNOW BANDS IN THE FINGER LAKES AND IMMEDIATELY SOUTH.
HOWEVER...LIGHT ACCUMULATIONS WILL TEND TO SUBLIMATE SOME IN THE
AFTERNOON BECAUSE OF THE VERY DRY AIR.
WITH THE WIND PICKING UP TO A STEADY 10-15 MPH AND GUSTS OF 20-25
MPH...TEMPERATURES MAINLY IN THE UPPER SINGLE DIGITS TO TEENS WILL
YIELD WIND CHILLS DIPPING BELOW ZERO DURING THE DAY MONDAY. THE
WIND WILL SLACKEN SOME MONDAY NIGHT...YET ACTUAL TEMPERATURES WILL
FALL INTO MAINLY SINGLE DIGITS TO AROUND 10. BELOW ZERO WIND
CHILLS ARE THUS FIGURED TO BE WIDESPREAD MONDAY NIGHT...AND EVEN
SOME TEENS BELOW ZERO POSSIBLE IN HIGHER TERRAIN EAST OF I-81.
DESPITE THE VERY COLD START...TEMPERATURES WILL START TO MODERATE
TUESDAY AS AN EXPANSIVE 1039MB HIGH PRESSURE DRIFTS OVER THE
REGION. SUNSHINE WILL HELP ACHIEVE HIGHS OF MAINLY LOWER TO MID
20S TUESDAY...FOLLOWED BY TEENS FOR LOWS TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE WILL DOMINATE THE WEATHER WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT WITH MODERATING TEMPERATURES. ALL MEDIUM RANGE
MODELS INDICATE A MAIN LOW WILL TRACK UP THROUGH THE GREAT LAKES
FRIDAY INTO SATURDAY WITH SOME COASTAL DEVELOPMENT POSSIBLE.
TEMPERATURES WILL BE MARGINAL FOR RAIN OR SNOW ON MAINLY SOUTHERLY
WINDS. THE EURO AND CMC HAVE BACKED OFF ON PRECIP FOR FRIDAY NOW
WITH ONLY THE GFS SUGGESTING PRECIP FOR FRIDAY. USED SUPERBLEND
FOR POPS WHICH HAS SLIGHT CHC FRIDAY ANDTHIS MAKES THE MOST SENSE
BASED ON THE SLOWER EURO/CMC SOLTNS. FOR FRIDAY NIGHT AND
SATURDAY HAVE CHC POPS FOR A MIX OF RAIN AND SNOW SHOWERS WITH
THIS SYSTEM. THERE CUD EVEN BE SOME FREEZING RAIN. FOR NOW WILL
STICK TO RAIN AND SNOW AS THERE ARE MANY UNCERTAINITIES. HEAVILY
USED SUPERBLEND FOR TEMPS, DEWPOINTS, WINDS AND POPS FOR DAYS 4-8.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
VISIBLE SATELLITE IMAGERY SHOWS WIDESPREAD CLOUDS ACROSS ALL WFO
BGM TERMINALS. CIGS WERE MAINLY MVFR-VFR RUNNING FROM ROUGHLY 2500
TO 3500 FEET AGL. THERE WERE A FEW SNOW SHOWERS AROUND BUT THE
MAIN BAND OF SNOW SHOWERS WAS EAST OF LAKE ONTARIO NORTH OF ONEIDA
CO. RAP13...NAM12 AND THE HRRR ALL PROJECT THIS BAND TO DROP
SOUTH REACHING SYR AND RME BTWN 18Z AND 21Z, AND 20-23Z ITH. THIS
SNOW BAND SHOULD BE LIFR IN SN AND CIGS. FARTHER SOUTH BY THE
TIME IT REACHES ELM AND BGM IT WILL WEAKEN SOME SO WE EXPECT IFR
IN SN AND CIG BOTH SITES. THE SNOW BAND IS NOT EXPECTED TO MAKE IT
ALL THE WAY TO KAVP. AFTER THIS BAND PASSES SOUTH, WINDS TURN
MORE NRLY AND THE FINGER LAKES REGION WILL SEE THE BULK OF A
MULTI-BAND LAKE EFFECT SNOWS WITH FINGER LAKES ENHANCEMENT. HAVE
LIFR AT ITH FROM 6Z ON THRU 18Z MON. HAVE ELM DOWN TO IFR
OVERNIGHT AND MON AM AS WELL. REST OF TAFS WILL IMPROVE TO VFR BY
MON AM.
WESTERLY WINDS AROUND 10-15 KNOTS WITH GUSTS OF 20 TO 25 KNOTS AT
TIMES WITH TURN NORTH TO NORTHWEST BY THIS EVENING WITH ROUGHLY
THE SAME SPEEDS THRU MON AM.
.OUTLOOK...
MONDAY PM-MON NIGHT...BRIEF RESTRICTIONS IN LAKE EFFECT SNOW
SHOWERS KITH-KELM.
TUESDAY THROUGH THURSDAY...VFR.
FRIDAY...POSSIBLE RESTRICTIONS IN RAIN SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP/MSE
SHORT TERM...MDP
LONG TERM...DJN
AVIATION...DJN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1235 PM EST SUN JAN 3 2016
.SYNOPSIS...
AN ARCTIC COLD FRONT WILL DROP THROUGH THE AREA THIS AFTERNOON
AND EVENING...ACCOMPANIED BY SCATTERED TO WIDESPREAD SNOW SHOWERS
PRIMARILY ACROSS CENTRAL NEW YORK. THE FRONT WILL ABRUPTLY BRING
IN THE COLDEST AIR MASS SO FAR THIS SEASON TONIGHT THROUGH MONDAY
NIGHT. THIS WILL INCLUDE WIND CHILLS DROPPING TO AROUND OR BELOW
ZERO MONDAY. ALSO...SCATTERED SNOW SHOWERS AND FLURRIES WILL
LINGER MAINLY IN THE FINGER LAKES REGION TO CENTRAL TWIN TIERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATED AT NOON... ARCTIC COLD FRONT IS CURRENTLY LOCATED ALONG
THE NORTH SHORE OF LAKE ONTARIO DROPPING SOUTH. MEANWHILE... A
LARGE AREA OF LIGHT SNOW HAS DEVELOPD ACROSS MUCH OF CENTRAL NEW
YORK EARLY THIS AFTERNOON AND A HEAVIER BAND OF SNOW HAS
INTENSIFIED EAST OF LAKE ONTARIO. EXPECT THIS BAND OF HEAVIER SNOW
TO SLOWLY DROP SOUTH AND WILL PROBABLY BECOME LINKED WITH THE
ARCTIC FRONT LATER THIS AFTERNOON AS IT DROPS SOUTH ACROSS CENTRAL
NY. EXPECT A QUICK 2 TO 4 INCHES OF SNOW WITH THIS BAND AS IT
DROPS SOUTH INTO THE SYRACUSE AREA EARLY THIS AFTERNOON... THEN
LESS THAN 2 INCHES AS IT LOOSES IT BEST CONNECTION WITH THE LAKE
LATER THIS AFTERNOON. TEMPERATURES THIS AFTERNOON WILL BE IN THE
MID 30S... BUT WILL DROP RAPIDLY LATER THIS AFTERNOON WITH THE
PASSAGE OF THE ARCTIC FRONT. HAVE MADE SOME TWEAKS TO OUR SNOWFALL
FORECASTS TO ACCOUNT FOR THESE EXPECTATIONS THIS AFTERNOON AND
HAVE ALSO RAISED SNOW AMOUNTS SOUTH-SOUTHEAST OF THE FINGER LAKES
FOR LATER TONIGHT INTO MONDAY WITH NNW FLOW EXPECTED. PREVIOUS
DISCUSSION IS BELOW.
245 AM UPDATE...
MAIN CONCERN IS THE STRONG ARCTIC FRONT WHICH WILL DROP THROUGH
THE REGION THIS AFTERNOON AND EVENING...ACCOMPANIED BY GUSTY SNOW
SHOWERS-BRIEF SQUALLS MAINLY IN CENTRAL NEW YORK. THIS WILL BE
FOLLOWED BY SETTING UP OF SOME LAKE EFFECT SNOW IN THE FINGER
LAKES REGION LATE TONIGHT AS THE COLDEST AIR MASS OF THE SEASON
RUSHES SOUTHWARD FROM CANADA.
AHEAD OF THE FRONT...THINGS ARE PRETTY QUIET CURRENTLY WITH PATCHY
MID TO HIGH CLOUDS AND TEMPERATURES HOLDING IN THE MID 20S TO
LOWER 30S. HOWEVER...LOW PRESSURE IS CROSSING THE ONTARIO-QUEBEC
BORDER...WITH THE ARCTIC FRONT NOW SLIDING DOWN OVER THE NORTHERN
GREAT LAKES REGION. AS THE LOW QUICKLY TRANSLATES TO NORTHERN
MAINE THIS AFTERNOON...THE ARCTIC FRONT WILL DROP OUT OF CANADA
INTO NEW YORK...THEN CONTINUE THROUGH NORTHERN PA THIS EVENING.
WITH THE ENHANCEMENT OF GREAT LAKES MOISTURE...THE FRONT WILL BE
ACCOMPANIED BY GUSTY SNOW SHOWERS. OVERALL AMOUNTS WILL NOT BE
VERY MUCH THROUGH THIS EVENING...FROM 1-2 INCHES IN CENTRAL NEW
YORK TO LESS THAN AN INCH IN THE TWIN TIERS...BUT THE MANNER IN
WHICH IT FALLS COULD BE SQUALLY IN NATURE IMMEDIATELY ALONG THE
FRONT.
WIND WILL QUICKLY VEER NW TO NNW TONIGHT...WHICH ALONG WITH STRONG
COLD AIR ADVECTION ACROSS A SHORTENING FETCH OF LAKE
ONTARIO...WILL TEND TO COMPRESS LAKE EFFECT SNOW SHOWERS TO MAINLY
THE FINGER LAKES REGION TO CENTRAL TWIN TIERS OVERNIGHT...WITH
JUST SCATTERED FLURRIES ELSEWHERE. SATURATED LAYER WILL BE QUITE
SHALLOW YET ALMOST ENTIRELY CONTAINED WITHIN DENDRITIC GROWTH
LAYER BY LATE TONIGHT...TO THE POINT THAT JUST ABOUT ANY CLOUD
LAYER WILL BE PRODUCING FLUFFY SNOWFLAKES. FLOW BY MONDAY MORNING
WILL BE FAVORABLE FOR FINGER LAKE BANDS ESPECIALLY CAYUGA-
SENECA...THE SOUTH SHORES OF WHICH COULD EASILY PICK UP A COUPLE
INCHES OR SO OF FLUFFY ACCUMULATION. FLOW IN GENERAL WILL BE
TRANSIENT AS IT BACKS IN DIRECTION...BUT FOR THE WINDOWS OF TIME
THINGS LINE UP...DECENT FINGER LAKE SNOW BANDS MAY OCCUR.
DAWN MONDAY WILL BE A RUDE AWAKENING TO ANYONE NOT PREPARED FOR
THE COLDEST AIR MASS SINCE LAST WINTER...WITH WIND CHILLS MAINLY IN
THE SINGLE DIGITS ABOVE OR BELOW ZERO /AND ACTUAL TEMPERATURES
MAINLY TEENS/.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
430 AM UPDATE...
COLDEST AIR MASS OF THE SEASON WILL PROVIDE A VERY RAW DAY TO
START THE WEEK...THOUGH IT WILL NOT STAY VERY LONG. WIND CHILLS
WILL ACTUALLY START TO DIVE BELOW ZERO DURING THE DAY MONDAY. I
HOPE YOU HAVE YOUR BEST WINTER WEATHER CLOTHING READY FOR
YOURSELF AND FOR THE KIDS AT THE BUS STOP.
HIGHS FOR MONDAY WILL ACTUALLY OCCUR AT MIDNIGHT TONIGHT...BECAUSE
STRONG COLD AIR ADVECTION WILL SEND 1000-500MB THICKNESS TO ONLY ABOUT
510 DECAMETERS BY MORNING...ALONG WITH 850MB TEMPERATURES IN THE
UPPER TEENS-LOW 20S BELOW ZERO CELSIUS. WE HAVE NOT HAD ANYTHING
LIKE THAT SINCE LATE LAST WINTER. LOW LEVEL FLOW WILL BE NNW TO N.
AIR MASS WILL BE VERY DRY...AND ARCTIC SUNSHINE CAN EVEN BE
EXPECTED TO BREAK OUT EAST OF I-81. TO THE WEST HOWEVER...SHALLOW
DECK OF CLOUDS STRETCHING FROM LAKE ONTARIO THROUGH THE FINGER
LAKES...INCLUDING CONTINUED LAKE EFFECT SNOW SHOWERS ESPECIALLY IN
THE MORNING. THOUGH THE SATURATED LAYER WILL BE SHALLOW...IT WILL
STILL BE ALMOST ENTIRELY AT DENDRITIC GROWTH TEMPERATURES...WHICH
WILL CONTINUE TO BE SUPPORTIVE OF VERY FLUFFY LOW WATER CONTENT
SNOW BANDS IN THE FINGER LAKES AND IMMEDIATELY SOUTH.
HOWEVER...LIGHT ACCUMULATIONS WILL TEND TO SUBLIMATE SOME IN THE
AFTERNOON BECAUSE OF THE VERY DRY AIR.
WITH THE WIND PICKING UP TO A STEADY 10-15 MPH AND GUSTS OF 20-25
MPH...TEMPERATURES MAINLY IN THE UPPER SINGLE DIGITS TO TEENS WILL
YIELD WIND CHILLS DIPPING BELOW ZERO DURING THE DAY MONDAY. THE
WIND WILL SLACKEN SOME MONDAY NIGHT...YET ACTUAL TEMPERATURES WILL
FALL INTO MAINLY SINGLE DIGITS TO AROUND 10. BELOW ZERO WIND
CHILLS ARE THUS FIGURED TO BE WIDESPREAD MONDAY NIGHT...AND EVEN
SOME TEENS BELOW ZERO POSSIBLE IN HIGHER TERRAIN EAST OF I-81.
DESPITE THE VERY COLD START...TEMPERATURES WILL START TO MODERATE
TUESDAY AS AN EXPANSIVE 1039MB HIGH PRESSURE DRIFTS OVER THE
REGION. SUNSHINE WILL HELP ACHIEVE HIGHS OF MAINLY LOWER TO MID
20S TUESDAY...FOLLOWED BY TEENS FOR LOWS TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
425 AM UPDATE...
UPDATED FORECAST TO REFLECT LATEST SUPERBLEND. MODELS ARE TRENDING
SLIGHTLY SLOWER WITH NEXT EVENT...MORE LIKE INTO FRIDAY NIGHT-
SATURDAY...OTHERWISE NOT MUCH CHANGE.
PREVIOUS DISCUSSION...
HIGH PRESSURE WILL DOMINATE THE WEATHER WEDNESDAY THROUGH THURSDAY
NIGHT WITH MODERATING TEMPERATURES. ALL MEDIUM RANGE MODELS
INDICATE SOME SORT OF COASTAL SYSTEM THAT WILL AFFECT THE REGION
ON FRIDAY. FOR NOW IT LOOKS LIKE MAINLY A RAIN EVENT SO HAVE
CHANCE POPS FOR RAIN SHOWERS ON FRIDAY. HEAVILY USED SUPERBLEND
FOR TEMPS, DEWPOINTS, WINDS AND POPS.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VISIBLE SATELLITE IMAGERY SHOWS WIDESPREAD CLOUDS ACROSS ALL WFO
BGM TERMINALS. CIGS WERE MAINLY MVFR-VFR RUNNING FROM ROUGHLY 2500
TO 3500 FEET AGL. THERE WERE A FEW SNOW SHOWERS AROUND BUT THE
MAIN BAND OF SNOW SHOWERS WAS EAST OF LAKE ONTARIO NORTH OF ONEIDA
CO. RAP13...NAM12 AND THE HRRR ALL PROJECT THIS BAND TO DROP
SOUTH REACHING SYR AND RME BTWN 18Z AND 21Z, AND 20-23Z ITH. THIS
SNOW BAND SHOULD BE LIFR IN SN AND CIGS. FARTHER SOUTH BY THE
TIME IT REACHES ELM AND BGM IT WILL WEAKEN SOME SO WE EXPECT IFR
IN SN AND CIG BOTH SITES. THE SNOW BAND IS NOT EXPECTED TO MAKE IT
ALL THE WAY TO KAVP. AFTER THIS BAND PASSES SOUTH, WINDS TURN
MORE NRLY AND THE FINGER LAKES REGION WILL SEE THE BULK OF A
MULTI-BAND LAKE EFFECT SNOWS WITH FINGER LAKES ENHANCEMENT. HAVE
LIFR AT ITH FROM 6Z ON THRU 18Z MON. HAVE ELM DOWN TO IFR
OVERNIGHT AND MON AM AS WELL. REST OF TAFS WILL IMPROVE TO VFR BY
MON AM.
WESTERLY WINDS AROUND 10-15 KNOTS WITH GUSTS OF 20 TO 25 KNOTS AT
TIMES WITH TURN NORTH TO NORTHWEST BY THIS EVENING WITH ROUGHLY
THE SAME SPEEDS THRU MON AM.
.OUTLOOK...
MONDAY PM-MON NIGHT...BRIEF RESTRICTIONS IN LAKE EFFECT SNOW
SHOWERS KITH-KELM.
TUESDAY THROUGH THURSDAY...VFR.
FRIDAY...POSSIBLE RESTRICTIONS IN RAIN SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...MDP/MSE
SHORT TERM...MDP
LONG TERM...DJN/MDP
AVIATION...DJN
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1225 AM CST SUN JAN 3 2016
.UPDATE...
ISSUED AT 1222 AM CST SUN JAN 3 2016
NO CHANGES REQUIRED FOR THIS UPDATE. STRATUS REMAINS CONFINED TO
THE RED RIVER VALLEY.
UPDATE ISSUED AT 927 PM CST SAT JAN 2 2016
WE DECIDED TO CONTINUE HOLDING OFF ON ADDING ANY FOG MENTION TO
THE FORECAST TONIGHT SINCE CONFIDENCE IN ITS DEVELOPMENT REMAINS
MODEST AT BEST. OPERATIONAL HRRR SIMULATIONS ARE THE MOST ROBUST
WITH FOG POTENTIAL...WHILE THE EXPERIMENTAL /ESRL/ HRRR HAS ONLY
RECENTLY BEGUN TO HINT AT SOME POTENTIAL SUNDAY MORNING OVER THE
MISSOURI RIVER VALLEY REGION. THE 00 UTC NAM-NEST CALLS FOR VERY
LITTLE IF ANY FOG DEVELOPMENT...AND NEITHER DOES THE 00 UTC NAM
MOS /MET/ GUIDANCE. THUS...ALL WE DID FOR THIS UPDATE WAS BLEND
OBSERVED TRENDS INTO RECENT TIME-LAGGED SHORT RANGE MODEL OUTPUT
FOR ONLY MINOR CHANGES TO THE FORECAST.
UPDATE ISSUED AT 557 PM CST SAT JAN 2 2016
LITTLE IN THE WAY OF CHANGE WAS MADE WITH THIS UPDATE. WE ARE A
BIT CONCERNED ABOUT PATCHY FOG AND/OR STRATUS DEVELOPMENT LATE
TONIGHT OVER CENTRAL ND ON THE WESTERN EDGE OF THE WELL-FORMED
STRATUS DECK ENTERING THE RED RIVER VALLEY AS OF 2345 UTC...BUT
THERE/S NOT A COHESIVE SIGNAL IN HIGH-RESOLUTION MODEL GUIDANCE
FOR THAT POTENTIAL YET. WE THEREFORE LEFT IT OUT OF THE FORECAST
AT THIS POINT...BUT WILL REVISIT IT LATER THIS EVENING AS LIGHT
WIND FIELDS AND A BIT OF SNOWMELT TODAY COULD SUPPORT SOME FOG.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 229 PM CST SAT JAN 2 2016
CURRENT SURFACE ANALYSIS PLACES LOW OVER LAKE SUPERIOR INTO
SOUTHERN ONTARIO WITH HIGH STRETCHING FROM THE NORTHERN INTO THE
CENTRAL ROCKIES. BREEZY NORTHWESTERLY WINDS CONTINUE OVER CENTRAL
INTO EASTERN NORTH DAKOTA BETWEEN THESE TWO SYSTEMS. UPPER LEVEL
ANALYSIS PLACES A BLOCKING PATTERN TO THE WEST RESULTING IN
QUIET NORTHWESTERLY FLOW OVER OUR AREA.
FOR TONIGHT INTO SUNDAY...BLOCKING PATTERN REMAINS IN PLACE
BRINGING QUIET WEATHER TO THE REGION. A SLIGHTLY COOLER AIRMASS
WORKS INTO THE AREA BRINGING COOLER TEMPERATURES FOR SUNDAY...THOUGH
READINGS WILL STILL BE NEAR AVERAGE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 229 PM CST SAT JAN 2 2016
THE LATEST WATER VAPOR IMAGERY SHOWS A NORTHWEST FLOW INTO NORTH
DAKOTA WITH A REX BLOCK PATTERN CONTINUING FARTHER WEST...AS AN
UPPER HIGH REMAINS SITUATED OVER SOUTHERN ALBERTA WHILE AN UPPER LOW
CIRCULATES IN SOUTHERN OREGON. AS THE THE UPPER LOW MOVES NORTH
ALONG THE WEST COAST AND ELONGATES OUT TO THE EAST...A PORTION OF
ITS ENERGY UNDERCUTS THE RIDGE WITH A SEPARATE CLOSED LOW DEVELOPING
SUNDAY NIGHT IN SOUTHEAST ALBERTA/SOUTHWEST SASKATCHEWAN.
AS THE UPPER RIDGE REBUILDS OVER ALBERTA MONDAY...A DOWNSTREAM
SOUTHEAST PUSH OF THE UPPER LOW INITIATES. IN DOING SO...LOW LEVEL
WARM AIR ADVECTION SPREADS FROM WEST TO EAST SUNDAY NIGHT AND
CONTINUES THROUGH MONDAY. THEN A SUBTLE COLD FRONT ASSOCIATED WITH
THE ABOVE MENTIONED UPPER LOW SHIFTS THROUGH LATE MONDAY NIGHT
NORTHWEST...AND CENTRAL AREAS TUESDAY MORNING INTO THE EARLY TUESDAY
AFTERNOON. NO PRECIPITATION IS ASSOCIATED WITH THE FRONTAL
PASSAGE...HOWEVER TEMPERATURES WILL COOL TO NEAR NORMAL HIGHS FOR
THIS TIME OF YEAR. EXPECT HIGHS BETWEEN 10F AND 20F WEDNESDAY INTO
FRIDAY. THE UPPER LEVEL FLOW DOES SHIFT TO A WESTERLY AND
SOUTHWESTERLY DIRECTION TUESDAY INTO FRIDAY...ALLOWING A FEW WEAK
SHORTWAVES TO MIGRATE THROUGH. THE GFS AND ECMWF BOTH AGREE THAT
PERIODIC BOUTS OF LIGHT SNOW POSSIBLE THURSDAY AFTERNOON THROUGH
FRIDAY NIGHT. THE ECMWF ACTUALLY WANTS TO INITIATE LIGHT SNOW
CHANCES AS EARLY AS WEDNESDAY AFTERNOON. HOWEVER THE SUPERBLEND
CONSENSUS SUGGESTS NOT UNTIL THURSDAY NIGHT. BEYOND FRIDAY...A
SIGNIFICANT CHUNK OF COLD AIR...PER GFS AND ECMWF...WILL SLOWLY SAG
INTO NORTH DAKOTA BEGINNING SATURDAY AFTERNOON AND CONTINUE THROUGH
THE EARLY PART OF THE FOLLOWING WEEK. DIFFERENCES EXIST IN THE
TIMING AND OVERALL MAGNITUDE OF THE 850MB TEMPERATURES THAT WILL
ENCOMPASS WESTERN AND CENTRAL NORTH DAKOTA. IN ADDITION...THE 00Z
NAEFS IS STILL NOT SIGNALING ANY SIGNIFICANT H850 TEMPERATURE VALUES
OUTSIDE OF CLIMATOLOGY LATE NEXT WEEK. HOWEVER WILL NEED TO MONITOR
THE POTENTIAL FOR WINDCHILL HEADLINES LATE NEXT WEEKEND AND INTO THE
FOLLOWING WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1222 AM CST SUN JAN 3 2016
VFR CONDITIONS AT ALL TAF SITES THROUGH THE PERIOD. PATCHY FOG IS
POSSIBLE LATER TONIGHT...HOWEVER CONFIDENCE IS NOT HIGH ENOUGH TO
WARRANT ANY MENTION IN A TAF.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...JJS
LONG TERM...KS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS PORTLAND OR
1105 AM PST SUN JAN 3 2016
.SYNOPSIS...WITH COLD AIR ENTRENCHED OVER THE INTERIOR PACIFIC
NORTHWEST...A SERIES OF WEAK LOW PRESSURE SYSTEMS APPROACHING FROM
THE SOUTH WILL PRODUCE A MIX OF FREEZING RAIN AND SNOW FOR MUCH OF
THE AREA THROUGH MONDAY MORNING. COLD AIR WILL SLOWLY MODERATE...
ENDING THE THREAT OF WINTRY PRECIPITATION FOR ALL BUT THE CASCADES
AND AREAS NEAR THE COLUMBIA GORGE AS THE NEXT SYSTEM ARRIVES TUESDAY.
ADDITIONAL WEAK WEATHER SYSTEMS WILL BRING LIGHT PRECIPITATION AT
TIMES THROUGH THE END OF THE UPCOMING WEEK.
&&
.MORNING UPDATE...BUSY MORNING WITH A WIDE VARIETY OF PRECIPITATION
TYPES ACROSS SW WASHINGTON AND NW OREGON. LIGHT ISENTROPIC LIFT AND
SOME WEAK DEFORMATION ARE CONTRIBUTING TO A PERSISTENT BAND OF
PRECIPITATION FROM THE NORTH OREGON COAST THROUGH THE PDX METRO AND
MUCH OF INLAND SW WASHINGTON. ACCUMULATIONS GENERALLY AROUND AN INCH
SO FAR AROUND THE METRO AREA...WITH SEVERAL REPORTS OF CRASHES ON
AREA HIGHWAYS DUE TO SNOWY/ICY ROADS. THE NORTH COAST IS NOT FARING
MUCH BETTER...WITH SIGNIFICANT ICING LINCOLN CITY NORTHWARD. DECIDED
TO ADD THE NORTH COAST TO THE WINTER WX ADVISORY...AND ELIMINATE
MENTION OF ELEVATIONS AS IT APPEARS THE FOOTHILL ELEVATIONS WILL
PROBABLY SEE 2-4 INCHES OF SNOW BY THE TIME ALL IS SAID AND DONE MON
MORNING.
WATER VAPOR IMAGERY SUGGESTS THE UPPER LOW WHICH WAS EXPECTED TO MOVE
INTO SOUTHERN BC HAS ACTUALLY WOBBLED A BIT TO THE W-NW...AND REMAINS
NEAR THE WA COAST. THE POSITION OF THIS UPPER LOW IS LIKELY
CONTRIBUTING TO DEFORMATION AND A SLOWER LIFT NORTHWARD OF THE AREA
OF STRONGEST ISENTROPIC LIFT IN 850-700 MB. NATURAL FRONTOGENESIS IS
ALSO OCCURRING DUE TO COLD AIR CONTINUING TO STREAM WESTWARD THROUGH
THE GORGE...WITH RELATIVELY WARMER AIR HAVING DIFFICULTY CREATING A
SIGNIFICANT DENT IN THIS COLD AIR OUTFLOW. THIS SYSTEM IS JUST TOO
WEAK TO REALLY SCOUR OUT THE COLD AIR...THEREFORE WOULD NOT BE
SURPRISED TO SEE OCCASIONAL SNOW/SLEET CONTINUE THROUGH TONIGHT AND
POSSIBLY MON MORNING ACROSS THE PDX METRO.
FURTHER TO THE SOUTH...WARMER IS HAVING A LITTLE EASIER OF A TIME
MOVING IN ALOFT. EXPECT AREAS S OF SALEM TO BE PRIMARILY FREEZING
RAIN OR DRIZZLE DUE TO THE WARM NOSE MOVING IN NEAR 850 MB.
PRECIPITATION WILL ALSO BE LIGHTER AND LESS PERSISTENT SOUTH OF SALEM
WITH THE MAIN FGEN BAND STAYING TO THE NORTH. HOWEVER IT DOES APPEAR
ANOTHER BAND OF PRECIPITATION IS WORKING NORTHWARD FROM DOUGLAS INTO
LANE COUNTY...THIS IS LIKELY ANOTHER SURGE OF WARM AIR ALOFT AND WILL
PROBABLY FALL MOSTLY AS FREEZING RAIN AS IT WORKS NORTHWARD TO SALEM.
AGAIN IT DOES NOT APPEAR THE WARM ADVECTION ALOFT WILL BE STRONG
ENOUGH TO SCOUR OUT THE COLD AIR COMING FROM THE GORGE...SO THIS WILL
PROBABLY BE SNOW OR SLEET AS IT MOVES INTO THE PDX METRO. FINALLY
MODEL SOUNDINGS SUGGEST PRECIP WILL CHANGE TO SLEET OR FREEZING RAIN
IN THE PDX METRO THIS EVENING...BUT MODELS HAVE CONSISTENTLY BEEN TOO
BULLISH WITH THE WARM AIR ALOFT. SUSPECT IT WILL BE LATER TONIGHT OR
MON MORNING BEFORE SNOW/SLEET ARE COMPLETELY OUT OF THE PICTURE AS
THE PRIMARY PRECIP TYPE IN THE PDX METRO. HRRR RUNS ALSO SUGGEST
PRECIPITATION WILL BE TAPERING OFF AROUND 06Z...WHICH COULD CAUSE A
TRANSITION TO FREEZING DRIZZLE BEFORE TAPERING OFF ALTOGETHER MON
MORNING. WITH PERSISTENT FORCING...WOULD NOT BE SURPRISED IF SOME OF
THE PDX/VUO METRO AREA BUMPS UP AGAINST WARNING CRITERIA OF 4
INCHES...BUT 2-3 INCHES WILL PROBABLY BE MORE COMMON AND THE ADVISORY
LOOKS SUFFICIENT FOR NOW.
THIS IS A DYNAMIC SITUATION...SO THERE WILL LIKELY BE SOME CHANGES
COMING WITH THE AFTERNOON FORECAST PACKAGE. WITH COLD AIR ENTRENCHED
EAST OF THE CASCADES AND TEMPS IN THE TEENS...THERE MAY BE SOME
WINTER WX ISSUES IN AT LEAST EASTERN PORTIONS OF THE PDX METRO AS THE
NEXT SYSTEM LIFTS UP FROM THE SOUTH MON NIGHT/TUE. WEAGLE
/PREV SHORT AND LONG TERM DISC ISSUED 339 AM PST SUN JAN 3 2016/
.SHORT TERM...LOW ELEVATION WINTER WEATHER IS LOOKING VERY PROMISING
TODAY AS WIDESPREAD SUB FREEZING TEMPERATURES CONTINUES AS A BAND OF
PRECIPITATION APPROACHES FROM THE SOUTH. PORTIONS OF SW OREGON HAVE
ALREADY SEEN BRIEF SNOW OR FREEZING RAIN OVERNIGHT WHICH HAS BOOSTED
THE FORECAST CONFIDENCE FOR LOW ELEVATION SNOW FOR NW OREGON THIS
MORNING AND FOR SW WASHINGTON THIS AFTERNOON.
MOISTURE FROM A FRONT OFF OF CALIFORNIA IS BEING ENTRAINED AROUND A
LOW OVER WASHINGTON STATE...CREATING A BAROCLINIC BOUNDARY THAT WILL
PRODUCE THE INITIAL BAND OF WINTRY PRECIPITATION. CLOUDS ARE
BEGINNING TO STREAM OVER LANE COUNTY EARLY THIS MORNING. RADAR IS
SHOWING LIGHT REFLECTIVITIES ACROSS SOUTHERN LANE COUNTY AHEAD OF THE
MAIN BAROCLINIC BAND...AND WE HAVE RECEIVED ONE REPORT FROM A NWS
SPOTTER OF FREEZING RAIN WITH ACCUMULATING ICE. WEATHER STATIONS AND
WEB CAMS ARE ALSO SHOWING SOME LIGHT SNOW ON THE ROADS NEAR CORVALLIS
AND EUGENE.
ALTHOUGH THE PRECIPITATION MAY INITIALLY FALL AS FREEZING
RAIN...THINK EVAPORATIVE COOLING DUE TO THE PRECEDING DRY LOWER
LEVELS MAY RESULT IN THE PRECIPITATION TYPE TURNING TO SNOW OR SLEET
WHEN THE MAIN PRECIPITATION BAND MOVES IN IN A FEW HOURS. SOME
UNCERTAINTY LIES IN THE TIMING OF WHEN THIS WILL OCCUR...BUT
CURRENTLY THINK THE MAIN PRECIPITATION BAND WILL REACH EUGENE BY 7
AM...SALEM BY 10 AM AND PORTLAND AROUND NOON. THE PRECIPITATION TYPE
SHOULD THEN CHANGE BACK TO FREEZING RAIN...AND EVENTUALLY RAIN.
CLOUD COVER AND NO STRONG SOUTHERLY WINDS AT THE SURFACE WILL MAKE IT
DIFFICULT FOR THE TEMPERATURES TO RISE MUCH ABOVE FREEZING
TODAY...AND MIXED WINTRY PRECIPITATION MAY CONTINUE THROUGH MONDAY
MORNING. HAVE EXTENDED AND EXPANDED THE WINTER WEATHER ADVISORY TO
ACCOUNT FOR THIS.
EAST WINDS WILL CONTINUE THROUGH THE GORGE AND WILL PERSIST FOR THE
NEXT COUPLE OF DAYS. THE WINDS WILL GRADUALLY WEAKEN THIS
MORNING...BUT A 4 TO 6 MB DALLES TO TROUTDALE PRESSURE GRADIENT WILL
CONTINUE THROUGH AT LEAST TUESDAY. THIS WILL KEEP COLD AIR TRAPPED
NEAR THE SURFACE FOR THE COLUMBIA RIVER GORGE AND HOOD RIVER AREAS AS
THE NEXT SYSTEMS MOVE THROUGH. THERE SHOULD BE A BRIEF BREAK IN
PRECIPITATION LATE MONDAY MORNING BEFORE THE NEXT LOW BRINGS ANOTHER
ROUND OF PRECIPITATION MONDAY AFTERNOON THROUGH TUESDAY AFTERNOON. TJ
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...TUESDAY NIGHT
THROUGH SATURDAY...UPPER-LEVEL TROUGH OVER THE EASTERN PACIFIC KEEPS
PRECIPITATION IN THE FORECAST THROUGH MIDWEEK. SURFACE LOW SLIDING UP
THE COAST BRINGS GUSTY SOUTHERLY WINDS TO AT LEAST THE COAST TUESDAY
NIGHT...WITH BREEZY CONDITIONS POSSIBLE INLAND AS WELL IF THE MODELS
ARE CORRECT WITH THE TRACK OF THE LOW. THIS SYSTEM WILL BRING MORE
LIGHT RAIN AND SNOW TO OUR AREA THROUGH AT LEAST WEDNESDAY. MODELS
DIVERGE SIGNIFICANTLY ON THE FORECAST LATER NEXT WEEK...BUT THE
GENERAL TREND IS TO DRY OUT LATE THURSDAY INTO FRIDAY AS SHORTWAVE
RIDGING BUILDS IN. MODELS ARE ALL OVER THE PLACE ON SATURDAY...SO
LEANED A BIT TOWARDS CLIMATOLOGY AND PUT CHANCE POPS IN THE FORECAST.
THE GFS DOES BRING ANOTHER SYSTEM IN ON SATURDAY...BUT THE ECMWF HAS
IT DROPPING DOWN INTO CALIFORNIA
WHICH MAKES MORE SENSE WITH THE STORM TRACK SET UP DOWN IN THAT AREA.
-MCCOY
&&
.AVIATION...A FIRST BAND OF SN IS CURRENTLY AFFECTING KTTD TO KHIO
BUT WILL CONTINUE TO MOVE NORTH OUT OF THE AREA THROUGH ABOUT 18Z.
ADDITIONAL PRECIP IS DEVELOPING BEHIND IT AROUND KSLE AT THIS TIME
AND PRODUCING MORE OF A MIXED PRECIP TYPE INCLUDING
FZRA...PL...AND POSSIBLY STILL SOME SN. VIS WILL LIKELY BOUNCE
BETWEEN MVFR AND VFR WITH GENERALLY MVFR CIGS. ADDITIONAL PRECIP
WILL DEVELOP THROUGH THE FORECAST PERIOD...CONTINUING TO FALL AS A
WINTRY MIX WHICH MAY INCLUDE FZRA. GUSTY EAST WINDS CONTINUE OUT
OF THE GORGE BUT WILL LIKELY REMAIN AT OR BELOW 30 KT. ELSEWHERE
WINDS SHOULD REMAIN UNDER 10 KT.
KPDX AND APPROACHES...EAST WINDS GUSTING TO AROUND 30
KT...STRONGEST NEAR THE COLUMBIA RIVER GORGE. CURRENT SN BAND
SHOULD BE MOVING NORTH OF THE AREA BY AROUND 18Z WITH LESS STEADY
PRECIP MOVING IN BEHIND IT. HOWEVER PRECIP TYPE WILL LIKELY CHANGE
TO A MIX OF FZRA AND PL THIS AFTERNOON OR EVENING. VIS AND CIG
IMPROVING LIKELY TO MVFR BY AROUND 18Z BUT COULD SEE SOME
ADDITIONAL IFR CONDITIONS WITH PRECIP LATER TODAY.
&&
.MARINE...WINDS OUT OF THE EAST TO SOUTHEAST HAVE BEEN RIGHT
AROUND 20 KT FOR THE PAST NUMBER OF HOURS BUT DO NOT SEEM
CONSISTENTLY ABOVE THAT THRESHOLD SO WILL NOT ISSUE A SMALL CRAFT
ADVISORY AT THIS TIME. SWELL SLOWLY BUILDING TODAY TO AROUND 10 FT
WITH COMBINATION OF WESTERLY AND SOUTHERLY SWELL. WINDS WILL
REMAIN AROUND 20 KT THROUGH TODAY AND THEN DECREASE SOME TOMORROW.
SEAS REMAIN 9 TO 11 FT FOR THE NEXT FEW DAYS.
MEANWHILE...A SERIES OF STRONG STORM SYSTEMS SOUTH OF THE
ALEUTIANS WILL EVENTUALLY BUILD LONG PERIOD SWELL WHICH WILL
LIKELY ARRIVE ALONG THE WEST COAST MON NIGHT OR TUE...POSSIBLY
PUSHING SEAS TO THE 15 TO 20 RANGE FEET BY MIDWEEK. BOWEN/CULLEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 AM PST MONDAY FOR ALL
VALLEY...COAST RANGE...AND CASCADE FOOTHILLS ZONES...AS
WELL AS THE NORTH OREGON COAST...WESTERN AND CENTRAL GORGE
AND HOOD RIVER VALLEY.
WA...WINTER WEATHER ADVISORY UNTIL 10 AM PST MONDAY FOR GREATER
VANCOUVER AREA-I-5 CORRIDOR IN COWLITZ COUNTY-SOUTH
WASHINGTON CASCADE FOOTHILLS-WESTERN COLUMBIA RIVER GORGE.
WINTER WEATHER ADVISORY UNTIL 10 AM PST MONDAY FOR CENTRAL
COLUMBIA RIVER GORGE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL NOON PST MONDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT
60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 2 PM
PST THIS AFTERNOON.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 9 PM
THIS EVENING TO 1 AM PST MONDAY.
&&
$$
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 MEDFORD OR
904 PM PST SAT JAN 2 2016
.DISCUSSION...A FRONT ASSOCIATED WITH A LOW OFFSHORE TO THE
SOUTHWEST WILL GRADUALLY MOVE TOWARDS THE AREA AND LIGHT
PRECIPITATION WILL SPREAD INLAND LATE THIS EVENING THROUGH SUNDAY
MORNING. A COLD AND DRY AIRMASS OVER THE AREA WILL GRADUALLY
MOISTEN THIS EVENING. ANY PRECIPITATION IS EXPECTED TO BE VERY
LIGHT TONIGHT AND SUNDAY MORNING. PRECIPITATION MAY START OUT AS
SNOW THEN AS A WARM LAYER MOVES IN ALOFT TONIGHT AND SUNDAY
MORNING, EXPECT THE POTENTIAL FOR FREEZING RAIN, OR POSSIBLY
SLEET, IN SOME WESTERN VALLEYS. CURRENT OBSERVATIONS SUPPORT THE
NAM MODEL WHICH INDICATES THE WARM LAYER ALOFT MOVING INTO DEL
NORTE AND EVENTUALLY JOSEPHINE COUNTY THIS EVENING.
THE 00Z NAM AND THE LATEST HIGH RESOLUTION HRRR MODELS SUPPORT
THE BEST CHANCES FOR FREEZING RAIN TO DEVELOP THIS EVENING AND
TONIGHT IN JOSEPHINE COUNTY AS WELL AS FAR WESTERN SISKIYOU
COUNTY...THEN TONIGHT AND SUNDAY MORNING INTO DOUGLAS COUNTY. A
PERIOD OF FREEZING RAIN IS ALSO POSSIBLE IN THE ROGUE VALLEY IN
JACKSON COUNTY TONIGHT AND SUNDAY MORNING. FREEZING RAIN MAY BE
SPOTTY AND A MIX OF SNOW, FREEZING RAIN AND RAIN IS POSSIBLE IN
THESE WESTERN VALLEYS AS SNOW GRADUALLY CHANGES OVER TO RAIN.OF
NOTE, MODELS SHOW A BAND OF LIGHT PRECIPITATION BEGINNING IN
WESTERN SISKIYOU, CURRY AND JOSEPHINE COUNTIES AND SPREADING
NORTH AND EAST INTO COOS, DOUGLAS AND PORTIONS OF JACKSON,
KLAMATH, AND NORTHERN LAKE COUNTIES TONIGHT. SPOTTY LIGHT
PRECIPITATION IS ALSO POSSIBLE IN CENTRAL AND EASTERN SISKIYOU AND
MODOC COUNTIES TONIGHT. ADDITIONAL LIGHT PRECIPITATION IS FORECAST
TO MOVE UP FROM THE SOUTHWEST SUNDAY MORNING WITH AREAS OF LIGHT
PRECIPITATION CONTINUING, MAINLY FROM THE CASCADES WEST DURING
THE DAY SUNDAY AND INTO SUNDAY EVENING. A FREEZING RAIN ADVISORY
IS IN EFFECT FOR WESTERN VALLEYS. SEE THE WSWMFR PRODUCT FOR
DETAILS. HIGHER ELEVATIONS ABOVE 2000 TO 3000 FEET WILL LIKELY SEE
ONLY LIGHT SNOW TONIGHT, INCLUDING IN THE CASCADES AND TO THE
EAST. AS THE ATMOSPHERE WARMS SNOW LEVELS ARE EXPECTED TO RISE TO
AROUND 4000 FEET OR HIGHER LATE SUNDAY MORNING FOR LOCATIONS WEST
OF THE CASCADES. HOWEVER SNOW LEVELS WILL REMAIN LOW FROM THE
CASCADES EAST UNTIL LATE AFTERNOON AS THEY RISE TO AROUND 4000 TO
4500 FEET.
THE FORECAST REMAINS ON TRACK. HAVE LOWERED TEMPERATURES SLIGHTLY
EAST OF THE CASCADES BUT OTHERWISE MADE NO SIGNIFICANT CHANGES TO
THE FORECAST.
&&
.AVIATION...FOR THE 03/00Z TAF CYCLE...
CLOUDS ARE RAPIDLY ADVANCING NORTHWARD THIS AFTERNOON AS A WARM
FRONT OVERSPREADS THE AREA TONIGHT THROUGH SUNDAY MORNING. A WINTRY
MIX IS EXPECTED BETWEEN THE COAST RANGE AND THE CASCADES, THOUGH
AMOUNTS WILL BE LIGHT (AROUND 1 INCH OR LESS OF SNOW AND <0.10" OF
ICE). MVFR CONDITIONS AND MOUNTAIN OBSCURATIONS ARE EXPECTED TO PUSH
ACROSS SISKIYOU COUNTY IN CALIFORNIA THIS EVENING, WITH FREEZING
RAIN POSSIBLE WEST OF THE SHASTA VALLEY. FREEZING RAIN IS POSSIBLE
BEGINNING IN 06Z-09Z TIME FRAME ACROSS THE VALLEYS OF SOUTHWESTERN
OREGON. FROM ABOUT MEDFORD EASTWARD TO KLMT, SNOW FLURRIES OR LIGHT
SNOW IS EXPECTED TO BEGIN AROUND 09Z. A MIX OF MVFR AND IFR IS
EXPECTED AT THE PRIMARY AIR FIELDS EAST OF THE COAST SUNDAY MORNING,
WITH PRECIPITATION CHANGING TO RAIN BETWEEN 12Z AND 18Z. A WARMING
AIR MASS WILL LEAD TO IMPROVING CONDITIONS SUNDAY AFTERNOON. BTL
&&
.MARINE...UPDATED 300 PM PST SATURDAY, 2 JAN 2016... STRONG HIGH
PRESSURE INLAND WITH LOWER PRESSURE OFFSHORE WILL GIVE WAY TO A WARM
FRONT LIFTING NORTHWARD TONIGHT INTO SUNDAY BRINGING RAIN AND STEEP
BUILDING SEAS. BOUTS OF GUSTY SOUTHEAST TO SOUTH WINDS WITH STEEP
SEAS WILL CONTINUE EARLY NEXT WEEK WITH PERIODS OF RAIN. TUESDAY
THROUGH THURSDAY 14 TO 19 FOOT SEAS ARE POSSIBLE AS LONG PERIOD WEST
SWELL ARRIVES. BTL
&&
.PREV DISCUSSION... /ISSUED 612 PM PST SAT JAN 2 2016/
DISCUSSION...
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT...A CLOSED UPPER
LEVEL LOW CURRENTLY RESIDE OVER CENTRAL OREGON, BUT IT WILL NOT BE
STAYING LONG, AS ANOTHER STRONG WAVE OVER THE EASTERN PACIFIC IS
APPLYING PRESSURE IN ITS ATTEMPT TO TAKE OVER THE SAME REAL
ESTATE. BETWEEN THE TWO LOWS, A WEAK RIDGE OF WARM AIR WILL PASS
THROUGH OUR AREA, AND AT THE SURFACE, THIS WILL TAKE THE FORM OF
A WEAK WARM FRONT. HERE IS WHERE THE FORECAST TROUBLES OF THE
SHORT TERM ARISE.
VERY COLD, DRY AIR HAS BEEN IN PLACE OVER OUR FORECAST AREA FOR
THE PAST SEVERAL DAYS. ALTHOUGH THE WARM AIR WILL BE PUSHING NORTH
OVER US, MUCH OF THIS COLD AIR WILL REMAIN TRAPPED IN THE VALLEYS
WEST OF THE CASCADES. AS MOISTURE WITHIN THE WARM AIR FLOWS OVER
THE COLDER AIR, PRECIPITATION WILL FORM, AND IN THOSE COLD
VALLEYS, FREEZING RAIN APPEARS TO BE A LIKELY RESULT. FORTUNATELY
ENOUGH, WITH THE LOW LEVEL AIR SO DRY, MOST OF THE PRECIPITATION
WILL HAVE A HARD TIME MAKING IT TO THE SURFACE, SO ANY ICE
ACCUMULATIONS SHOULD BE LIGHT. MEANWHILE, SNOW LEVELS WILL BEGIN
THE EVENT TONIGHT AT AROUND 1000 FEET, THEN RISE QUICKLY TO ABOVE
4000 FEET BY NOON TOMORROW. THEREFORE, ANYONE TRAVELING ALONG
AREA ROADWAYS, PARTICULARLY INTERSTATE 5, COULD EXPERIENCE RAIN,
SNOW, FREEZING RAIN, OR A MIX OF ALL OF THE ABOVE. WHERE EXACTLY
WHICH TYPE OF PRECIPITATION OCCURS AND WHEN WILL DEPEND A GREAT
DEAL ON LOCAL FACTORS, SUCH AS SHELTERING, VARIANCES OF A DEGREE
OR TWO OF TEMPERATURE, CLOUD COVER, ETC., SO HAVE PAINTED A BROAD
BRUSH OF WHERE FREEING RAIN COULD OCCUR, AND ISSUED AN ADVISORY TO
COVER THE POSSIBILITY THROUGH TOMORROW MORNING. CONFIDENCE IS
HIGHER THAN PREVIOUS SHIFTS THAT ICY WEATHER WILL HAPPEN SOMEWHERE
WITHIN THE FORECAST AREA, BUT MUCH LOWER THAT IT WILL OCCUR AT ANY
SPECIFIC LOCATION.
WITH A TIGHT PRESSURE GRADIENT, PREDOMINANT FLOW WILL BE SOUTH TO
NORTH, AND THIS IS LIKELY TO RESULT IN SOME BREEZY TO GUSTY WINDS
ALONG EAST-WEST TRENDING RIDGE LINES, AS WELL AS IN THE SOUTHERN
SHASTA VALLEY AND THE ROGUE VALLEY NEAR ASHLAND. WHILE THIS TYPE
OF DOWNSLOPING WINDS IN THE VALLEYS CAN GREATLY INHIBIT
PRECIPITATION,AND THE WINDS NEAR ASHLAND SHOULD PRODUCE ENOUGH
WARMING TO PREVENT TEMPERATURES FROM DROPPING BELOW FREEZING, HAVE
KEPT FREEZING RAIN MENTION OUT OF ASHLAND. IN THE SHASTA VALLEY,
WINDS WILL BE STRONG ENOUGH TO WARRANT AN ADVISORY NEAR WEED, BUT
SNOW LEVELS SHOULD REMAIN LOW ENOUGH FOR ALL SNOW OR A SNOW-RAIN
MIX.
ALSO, IT IS POSSIBLE THAT AS THE WARM AIR PUSHES FARTHER INLAND
AND NORTH, THAT SNOW LEVELS WILL RISE ABOVE THE VALLEY FLOORS OF
THE EAST SIDE AND PORTIONS OF NORTHERN CALIFORNIA SUNDAY AFTERNOON
AND EVENING. HOWEVER, COLD AIR MAY STILL BE TRAPPED IN THE LOWER
LEVELS OF VALLEYS THERE, AND FREEZING RAIN IS NOT OUT OF THE
QUESTION FOR THESE AREAS AS WELL. THIS IS A NEW DEVELOPMENT IN THE
FORECAST, AND CONFIDENCE IN THIS SCENARIO IS MUCH MUCH LOWER THAN
FOR THE WEST SIDE, SO WILL LEAVE THIS FOR THE CONSIDERATION OF THE
EVENING AND NIGHT SHIFTS.
SUNDAY NIGHT, THE NEW LOW WILL BEGIN TO OPEN UP TO THE PARENT
TROUGH OVER THE EASTERN PACIFIC, THEN SLIDE NORTH INTO OUR AREA
ALONG WITH ITS ASSOCIATED COLD FRONT. THIS WILL BRING ANOTHER
ROUND OF PRECIPITATION TO THE REGION, AND PUSH SNOW LEVELS BACK
DOWN TO AROUND 3000 FEET. LIKE BEFORE, PRECIPITATION WILL BE
LIGHT, BUT THERE IS LITTLE CONCERN BY THIS POINT FOR ICY WEATHER,
ONLY THE NORMAL SNOW AND RAIN IS EXPECTED. PRECIPITATION CHANCES
WILL REMAIN IN THE AREA THROUGH TUESDAY NIGHT, AS THE TROUGH AXIS
PASSES OVERHEAD MONDAY NIGHT, AND YET ANOTHER WAVE ENTERS THE AREA
TUESDAY MORNING INTO THE AFTERNOON. -BPN
EXTENDED...(WEDNESDAY THROUGH SATURDAY)...SPLIT JET STREAM CONTINUES
DURING THIS PERIOD WITH THE SOUTHERN STREAM CARRYING MOST OF THE
ENERGY INTO NORTHERN CALIFORNIA. THIS DOES NOT MEAN SOUTHERN
OREGON WILL NOT SEE ANY PRECIPITATION...JUST THAT THE HEAVIER
AMOUNTS WILL BE FROM SISKIYOU MOUNTAINS SOUTH. BOTH THE GFS AND
THE ECMWF ARE FAIRLY CONSISTENT THROUGH THURSDAY AND BRING A BROAD
AREA OF LOW PRESSURE AND TROUGH INTO OUR AREA. THE MAIN TROUGH AND
THE LOW ARE FORECAST TO MOVE INTO NORTHERN CALIFORNIA. WITH THE
SNOW LEVELS AROUND 3500-4000 FEET THIS SYSTEM WILL BE A GOOD SNOW
PRODUCER FOR THE MOUNTAINS. SNOW AMOUNTS WILL ALSO BE REASONABLE
FOR THE CASCADES BUT IT DOES NOT APPEAR THAT THE FREMONT-WINEMA
FOREST WILL SEE AS MUCH SNOW AS IN RECENT STORMS.
BY THURSDAY NIGHT FLOW ALOFT TURNS MORE NORTH TO NORTHWEST AND
PRECIPITATION WILL TAPER OFF TO SHOWERS. BOTH MODELS BRING A RIDGE
INTO THE COASTAL WATERS ON FRIDAY BUT ALSO SHOW STRONG JET ENERGY
COMING INTO THE WEST SIDE OF THE RIDGE. WE ARE TRENDING THE POPS
DOWNWARD FOR FRIDAY EXCEPT FOR SOUTHERN SISKIYOU AND MODOC COUNTIES.
THE GFS WEAKENS THE RIDGE BY SATURDAY AND BRING ANOTHER FRONT AND
PRECIPITATION INLAND...WHEREAS THE ECMWF MAINTAINS THE RIDGE BUT
SLIDES A PIECE OF ENERGY UNDERNEATH AND INTO NORTHERN CALIFORNIA.
THE EC SOLUTION WOULD KEEP SOUTHERN OREGON DRY NEXT WEEKEND WHEREAS
THE GFS SOLUTION WOULD BE WET. WE ARE NOT TOTALLY CONFIDENT THAT THE
RIDGE WILL HOLD BUT INSTEAD MAY BE WEAK ENOUGH TO ALLOW SOME ENERGY
TO SLIP THROUGH AND THEREFORE WE WILL MAINTAIN A SLIGHT CHANCE OF
PRECIPITATION FOR NEXT WEEKEND. /FB
AVIATION...FOR THE 03/00Z TAF CYCLE... CLOUDS ARE RAPIDLY ADVANCING
NORTHWARD THIS AFTERNOON AS A WARM FRONT OVERSPREADS THE AREA
TONIGHT THROUGH SUNDAY MORNING. A WINTRY MIX IS EXPECTED BETWEEN THE
COAST RANGE AND THE CASCADES, THOUGH AMOUNTS WILL BE LIGHT (AROUND 1
INCH OR LESS OF SNOW AND <0.10" OF ICE). MVFR CONDITIONS AND
MOUNTAIN OBSCURATIONS ARE EXPECTED TO PUSH ACROSS SISKIYOU COUNTY IN
CALIFORNIA THIS EVENING, WITH FREEZING RAIN POSSIBLE WEST OF THE
SHASTA VALLEY. FREEZING RAIN IS POSSIBLE BEGINNING IN 06Z-09Z TIME
FRAME ACROSS THE VALLEYS OF SOUTHWESTERN OREGON. FROM ABOUT MEDFORD
EASTWARD TO KLMT, SNOW FLURRIES OR LIGHT SNOW IS EXPECTED TO BEGIN
AROUND 09Z. A MIX OF MVFR AND IFR IS EXPECTED AT THE PRIMARY AIR
FIELDS EAST OF THE COAST SUNDAY MORNING, WITH PRECIPITATION CHANGING
TO RAIN BETWEEN 12Z AND 18Z. A WARMING AIR MASS WILL LEAD TO
IMPROVING CONDITIONS SUNDAY AFTERNOON. BTL
MARINE...UPDATED 300 PM PST SATURDAY, 2 JAN 2016... STRONG HIGH
PRESSURE INLAND WITH LOWER PRESSURE OFFSHORE WILL GIVE WAY TO A WARM
FRONT LIFTING NORTHWARD TONIGHT INTO SUNDAY BRINGING RAIN AND STEEP
BUILDING SEAS. BOUTS OF GUSTY SOUTHEAST TO SOUTH WINDS WITH STEEP
SEAS WILL CONTINUE EARLY NEXT WEEK WITH PERIODS OF RAIN. TUESDAY
THROUGH THURSDAY 14 TO 19 FOOT SEAS ARE POSSIBLE AS LONG PERIOD WEST
SWELL ARRIVES. BTL
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR... FREEZING RAIN ADVISORY UNTIL 10 AM PST SUNDAY FOR ORZ024-026.
FREEZING RAIN ADVISORY FROM 1 AM TO 10 AM PST SUNDAY FOR
ORZ021-023-025.
CA...FREEZING RAIN ADVISORY UNTIL 10 AM PST SUNDAY FOR CAZ080-081.
WIND ADVISORY UNTIL 7 AM PST SUNDAY FOR CAZ081-083.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PST THURSDAY
FOR PZZ350-356.
HAZARDOUS SEAS WARNING FROM 10 AM TO 10 PM PST SUNDAY FOR
PZZ370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST WEDNESDAY
FOR PZZ370-376.
$$
CC/CC/CC
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
356 PM EST SUN JAN 3 2016
.SYNOPSIS...
NORTHWEST FLOW WILL CONTINUE TO DOMINATE THE PATTERN FOR THE NEXT
SEVERAL DAYS WITH THE COLDEST AIR OF THE SEASON EXPECTED TO START
THE FIRST FULL WEEK OF THE NEW YEAR. TEMPERATURES WILL BEGIN TO
MODERATE LATER IN THE WEEK AS HIGH PRESSURE BUILDS EASTWARD.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AN ARCTIC FRONT WILL PASS SOUTHWARD ACROSS PENNSYLVANIA THIS
EVENING INTO TONIGHT. THE LOW CLOUD SHIELD CONTINUES TO MAKE SLOW
PROGRESS SOUTHEASTWARD...AND SHOULD BE OVER THE LWR SUSQ VALLEY
BY SUNSET.
LATEST HRRR SHOWS SCATTERED SNOW SHOWERS WILL CONTINUE TO DEVELOP
DOWNWIND OF LAKE ERIE INTO WARREN AND MCKEAN COUNTIES THROUGH THE
LATE AFTERNOON HOURS.
THE BIG QUESTION IS TO WHAT EXTENT THE LAKE-EFFECT MACHINE CAN
GET CRANKED UP THIS EVENING INTO TONIGHT. MODEL SOUNDINGS DON`T
REALLY SHOW A FAVORABLE OVERLAKE ALIGNMENT TAKING PLACE FOR MUCH
MORE THAN A FEW HOURS BEFORE POST-FRONTAL LOW LEVEL WINDS COME
AROUND TO A MORE NORTHERLY/SHORTER OVERLAKE TRAJECTORY. STILL WITH
THE LAKES BEING UNSEASONABLY WARM...THE INSTABILITY SHOULD BE
ENOUGH FOR THE NORMAL SNOWBELT AREAS TO SEE ANYWHERE FROM A
COATING TO A FEW INCHES.
IT LOOKS LIKE OROGRAPHICALLY-ENHANCED SNOWS WILL FOCUS INTO THE
LAUREL HIGHLANDS FOR A TIME OVERNIGHT INTO EARLY MONDAY. THE
DRYNESS OF THE UPSTREAM AIRMASS AND THE SHORT DURATION OF BEST
ALIGNED FLOW SHOULD LIMIT ACCUMULATIONS THERE AS WELL...ALTHOUGH A
PERIOD OF STEADIER SNOW IS POSSIBLE OVERNIGHT.
OVERNIGHT LOWS IN THE TEENS TO LOW 20S WILL FEEL COLD COMPARED TO
WHAT THE SEASON HAS HAD TO OFFER TO DATE...BUT WILL ACTUALLY BE
VERY NEAR NORMAL FOR EARLY JANUARY.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
WINDS WILL BECOME MORE NORTHERLY MONDAY...AS HIGH PRESSURE BUILDS
IN AND BRINGS WITH IT THE COLDEST AIR OF THE SEASON TO DATE. 850MB
TEMPS OVER NRN PA WILL BE IN THE NEIGHBORHOOD OF -20C BY MONDAY
AFTERNOON...WHICH HAS NOT BEEN SEEN SINCE LAST WINTER.
AS THE SURFACE HIGH BUILDS EASTWARD AND THE UPPER TROUGH LIFTS
OUT...SNOW SHOWER ACTIVITY SHOULD GRADUALLY TAPER OFF THROUGH THE
DAY ON MONDAY.
IT WILL BE COLD ON MONDAY...WITH TEMPS NOT RISING MUCH FOR MOST
AREAS. HIGHS WILL HOLD IN THE TEENS IN THE NORTH AND THE 20S FOR
THE CENTRAL MTNS...AND A MODERATE BREEZE WILL ONLY ADD TO THE
CHILL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
TUESDAY MORNING WILL BRING THE COLDEST AIR OF THE WINTER
SEASON AS -22C 850MB AIR DIPS INTO NORTHERN PA...BUT A MODERATION
IS IN STORE FOR THE REMAINDER OF THE WEEK.
HIGH PRESSURE CENTERED OVER PENNSYLVANIA TUESDAY MORNING WILL
SLIDE OFF THE ATLANTIC COAST INTO THURSDAY. THIS WILL ALLOW FOR
MODERATING TEMPERATURES BOTH AT THE SURFACE AND ALOFT.
A 500 MB WAVE OVER THE CENTRAL PLAINS WILL LIFT TO THE NORTH LATE
IN THE WEEK. AN AREA OF MOISTURE OVER THE GULF COAST STATES WILL
BE DRAWN NORTH. AT THIS TIME...THE TROUGH AXIS REMAINS TO THE WEST
OF THE FORECAST AREA AS A WEAK LOW DEVELOPS NEAR THE MID ATLANTIC
COAST ON THURSDAY AND FRIDAY. BY SATURDAY...ANOTHER...STRONGER LOW
PRESSURE SYSTEM DEVELOPS OVER THE LOWER MISSISSIPPI VALLEY AND
MOVES NORTHEAST. THE LOW PRESSURE TRACK DIFFERS BETWEEN THE
LONGER RANGE MODELS AND THAT WILL AFFECT THE QPF. DOESN`T SEEM TO
BE ENOUGH COLD AIR IN THE CARDS TO GET EXCITED ABOUT THE PROSPECTS
FOR BIG SNOW.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
LOW CLOUDS CONTINUE TO PROGRESS SOUTHEASTWARD ACROSS CENTRAL
PA THIS AFTN. IFR CIGS NOW BEING REPORTED AT KBFD...WITH
GENERALLY MVFR IN THE CENTRAL MTNS. CLOUDS HAVE YET TO MAKE IT
INTO THE LWR SUSQ VALLEY...BUT THEY WILL AS THE AFTN PROGRESSES.
A COLD FRONT WILL DROP SOUTHEASTWARD ACROSS CENTRAL PA THIS
EVENING INTO TONIGHT...ACCOMPANIED BY SCTD SNOW SHOWERS AND
POSSIBLY A SQUALL. BEHIND THE FRONT...LAKE-EFFECT AND UPSLOPE
SNOW SHOWERS WILL CONTINUE TO AFFECT PRIMARILY THE WRN HIGHLANDS
/KBFD AND KJST/ OVERNIGHT INTO EARLY MONDAY...ACCOMPANIED BY
REDUCED CIGS AND VSBYS.
CONDITIONS SHOULD GRADUALLY IMPROVE ON MONDAY...AS HIGH PRES
BUILDS IN. AFTER THAT...HIGH PRES WILL REMAIN IN CONTROL THROUGH
THURS. THE NEXT WEATHER MAKER COULD BRING SOME RAIN SHOWERS INTO
CENTRAL PA BY FRI.
OUTLOOK...
SUN NIGHT-MON...REDUCTIONS ACROSS WESTERN HIGHER TERRAIN IN SNOW
SHOWERS AND POTENTIAL SQUALLS. MVFR CIG REDUCTIONS CENTRAL MTNS.
MAINLY VFR SE. BREEZY.
TUE-THU...NO SIG WX.
FRI...INCR CLOUDS...SHRA POSS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...EVANEGO
SHORT TERM...EVANEGO
LONG TERM...LA CORTE/TYBURSKI
AVIATION...EVANEGO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
201 PM EST SUN JAN 3 2016
.SYNOPSIS...
NORTHWEST FLOW WILL CONTINUE TO DOMINATE THE PATTERN FOR THE NEXT
SEVERAL DAYS WITH THE COLDEST AIR OF THE SEASON EXPECTED TO START
THE FIRST FULL WEEK OF THE NEW YEAR. TEMPERATURES WILL BEGIN TO
MODERATE LATER IN THE WEEK AS HIGH PRESSURE BUILDS EASTWARD.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN ARCTIC FRONT WILL PASS SOUTHWARD ACROSS PENNSYLVANIA THIS
EVENING INTO TONIGHT. THE LOW CLOUD SHIELD CONTINUES TO MAKE SLOW
PROGRESS SOUTHEASTWARD...AND SHOULD BE OVER THE LWR SUSQ VALLEY
BY SUNSET.
LATEST HRRR SHOWS SCATTERED SNOW SHOWERS WILL CONTINUE TO DEVELOP
DOWNWIND OF LAKE ERIE INTO WARREN AND MCKEAN COUNTIES THROUGH THE
LATE AFTERNOON HOURS.
THE BIG QUESTION IS TO WHAT EXTENT THE LAKE-EFFECT MACHINE CAN
GET CRANKED UP THIS EVENING INTO TONIGHT. MODEL SOUNDINGS DON`T
REALLY SHOW A FAVORABLE OVERLAKE ALIGNMENT TAKING PLACE FOR MUCH
MORE THAN A FEW HOURS BEFORE POST-FRONTAL LOW LEVEL WINDS COME
AROUND TO A MORE NORTHERLY/SHORTER OVERLAKE TRAJECTORY. STILL WITH
THE LAKES BEING UNSEASONABLY WARM...THE INSTABILITY SHOULD BE
ENOUGH FOR THE NORMAL SNOWBELT AREAS TO SEE ANYWHERE FROM A
COATING TO A FEW INCHES.
IT LOOKS LIKE OROGRAPHICALLY-ENHANCED SNOWS WILL FOCUS INTO THE
LAUREL HIGHLANDS FOR A TIME OVERNIGHT INTO EARLY MONDAY. THE
DRYNESS OF THE UPSTREAM AIRMASS AND THE SHORT DURATION OF BEST
ALIGNED FLOW SHOULD LIMIT ACCUMULATIONS THERE AS WELL...ALTHOUGH A
PERIOD OF STEADIER SNOW IS POSSIBLE OVERNIGHT.
OVERNIGHT LOWS IN THE TEENS TO LOW 20S WILL FEEL COLD COMPARED TO
WHAT THE SEASON HAS HAD TO OFFER TO DATE...BUT WILL ACTUALLY BE
VERY NEAR NORMAL FOR EARLY JANUARY.
&&
.SHORT TERM /MONDAY/...
WINDS WILL BECOME MORE NORTHERLY MONDAY...AS HIGH PRESSURE BUILDS
IN AND BRINGS WITH IT THE COLDEST AIR OF THE SEASON TO DATE. 850MB
TEMPS OVER NRN PA WILL BE IN THE NEIGHBORHOOD OF -20C BY MONDAY
AFTERNOON...WHICH HAS NOT BEEN SEEN SINCE LAST WINTER.
AS THE SURFACE HIGH BUILDS EASTWARD AND THE UPPER TROUGH LIFTS
OUT...SNOW SHOWER ACTIVITY SHOULD GRADUALLY TAPER OFF THROUGH THE
DAY ON MONDAY.
IT WILL BE COLD ON MONDAY...WITH TEMPS NOT RISING MUCH FOR MOST
AREAS. HIGHS WILL HOLD IN THE TEENS IN THE NORTH AND THE 20S FOR
THE CENTRAL MTNS...AND A MODERATE BREEZE WILL ONLY ADD TO THE
CHILL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AFTER THE COLDEST AIR OF THE YOUNG WINTER SEASON SETTLES OVER THE
AREA TUESDAY MORNING...QUIET WEATHER WILL RETURN AS WE START TO
ENJOY THE BENEFITS OF RAPIDLY BUILDING HEIGHTS ALOFT WITH THE
RETURN OF THE EASTERN RIDGE...FOR AT LEAST A FEW DAYS. MODERATING
TEMPERATURES WILL CONTINUE THROUGH THE EXTENDED PERIOD AFTER WE
WILL THE WEEK SEVERAL DEGREES COOLER THAN NORMAL BUT...BY MID TO
LAKE WEEK...THAT WILL REVERSE AND RETURN TO SEVERAL DEGREES WARMER
THAN NORMAL.
A COMPLEX STORM/FRONTAL SYSTEM WILL APPROACH FOR THE END OF THE
WEEK. LOW PRESSURE TRACK DIFFERS BETWEEN THE LONGER RANGE MODELS
AND THAT WILL AFFECT THE QPF. DOESN`T SEEM TO BE ENOUGH COLD AIR
IN THE CARDS TO GET EXCITED ABOUT THE PROSPECTS FOR BIG SNOW
HOWEVER.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
LOW CLOUDS CONTINUE TO PROGRESS SOUTHEASTWARD ACROSS CENTRAL
PA THIS AFTN. IFR CIGS NOW BEING REPORTED AT KBFD...WITH
GENERALLY MVFR IN THE CENTRAL MTNS. CLOUDS HAVE YET TO MAKE IT
INTO THE LWR SUSQ VALLEY...BUT THEY WILL AS THE AFTN PROGRESSES.
A COLD FRONT WILL DROP SOUTHEASTWARD ACROSS CENTRAL PA THIS
EVENING INTO TONIGHT...ACCOMPANIED BY SCTD SNOW SHOWERS AND
POSSIBLY A SQUALL. BEHIND THE FRONT...LAKE-EFFECT AND UPSLOPE
SNOW SHOWERS WILL CONTINUE TO AFFECT PRIMARILY THE WRN HIGHLANDS
/KBFD AND KJST/ OVERNIGHT INTO EARLY MONDAY...ACCOMPANIED BY
REDUCED CIGS AND VSBYS.
CONDITIONS SHOULD GRADUALLY IMPROVE ON MONDAY...AS HIGH PRES
BUILDS IN. AFTER THAT...HIGH PRES WILL REMAIN IN CONTROL THROUGH
THURS. THE NEXT WEATHER MAKER COULD BRING SOME RAIN SHOWERS INTO
CENTRAL PA BY FRI.
OUTLOOK...
SUN NIGHT-MON...REDUCTIONS ACROSS WESTERN HIGHER TERRAIN IN SNOW
SHOWERS AND POTENTIAL SQUALLS. MVFR CIG REDUCTIONS CENTRAL MTNS.
MAINLY VFR SE. BREEZY.
TUE-THU...NO SIG WX.
FRI...INCR CLOUDS...SHRA POSS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...EVANEGO
SHORT TERM...EVANEGO
LONG TERM...LA CORTE
AVIATION...EVANEGO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1024 AM EST SUN JAN 3 2016
.SYNOPSIS...
NORTHWEST FLOW WILL CONTINUE TO DOMINATE THE PATTERN FOR THE NEXT
SEVERAL DAYS WITH THE COLDEST AIR OF THE SEASON EXPECTED TO START
THE FIRST FULL WEEK OF THE NEW YEAR. TEMPERATURES WILL BEGIN TO
MODERATE LATER IN THE WEEK AS HIGH PRESSURE BUILDS EASTWARD.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN ARCTIC FRONT WILL PASS SOUTHWARD ACROSS PENNSYLVANIA THIS
AFTERNOON INTO TONIGHT...AND THE LOW CLOUD SHIELD CONTINUES TO
MAKE PROGRESS SOUTHEASTWARD.
LATEST HRRR SHOWS SCATTERED SNOW SHOWERS REDEVELOPING DOWNWIND OF
LAKE ERIE INTO WARREN AND MCKEAN COUNTIES AND CONTINUING THROUGH
AT LEAST THE AFTERNOON HOURS.
THE BIG QUESTION IS TO WHAT EXTENT THE LAKE-EFFECT MACHINE CAN
GET CRANKED UP. MODEL SOUNDINGS DON`T REALLY SHOW A FAVORABLE
OVER-LAKE ALIGNMENT TAKING PLACE FOR MUCH MORE THAN A FEW HOURS
THIS AFTERNOON BEFORE POST-FRONTAL LOW LEVEL WINDS COME AROUND TO
A MORE NORTHERLY/SHORTER OVERLAKE TRAJECTORY AND OVERALL INVERSION
HEIGHTS START TO FALL LATER DURING THE EVENING AND OVERNIGHT.
STILL WITH THE LAKES BEING UNSEASONABLY WARM...THE INSTABILITY
SHOULD BE ENOUGH FOR THE NORMAL SNOW BELT AREAS TO SEE ANYWHERE
FROM A COATING TO A FEW INCHES. AT THIS TIME...I DON`T HAVE HIGH
ENOUGH CONFIDENCE THAT ADVISORY NUMBERS CAN BE MET IN A 12 HOUR
WINDOW TO WARRANT A WINTER WX HEADLINE.
IT LOOKS LIKE OROGRAPHICALLY-ENHANCED SNOWS WILL FOCUS INTO THE
LAURELS FOR A TIME OVERNIGHT INTO EARLY MONDAY. THE DRYNESS OF THE
UPSTREAM AIRMASS AND THE SHORT DURATION OF BEST ALIGNED FLOW
SHOULD SIMILARLY LIMIT ACCUMULATIONS TO MAINLY NUISANCE NUMBERS
THERE.
OVERNIGHT LOWS IN THE TEENS TO LOWER TWENTIES WILL FEEL COLD
COMPARED TO WHAT THE SEASON HAS HAD TO OFFER TO DATE...BUT WILL
ACTUALLY BE VERY NEAR NORMAL FOR EARLY JANUARY.
&&
.SHORT TERM /MONDAY/...
THE COLD FRONT THAT WILL PASS LATER TONIGHT AND TURN THE WINDS
FLOW TO A MORE NORTHERLY TRAJECTORY...BRINGING IN THE COLDEST AIR
OF THE SEASON TO DATE.
850MB TEMPS OVER NRN PA WILL BE IN THE NEIGHBORHOOD OF -20C BY
MONDAY AFTERNOON...WHICH HAS NOT BEEN SEEN SINCE LAST WINTER.
AS THE SURFACE HIGH BULGES EAST AND THE UPPER TROUGH STARTS
LIFTING OUT...SNOW SHOWER ACTIVITY SHOULD BEGIN TO TAPER OFF
THROUGH THE DAY ON MONDAY.
WE ARE IN FOR A DEFINITE JANUARY-FEELING DAY ON MONDAY...WITH
TEMPS NOT RISING MUCH FOR MOST AREAS. HIGHS WILL HOLD IN THE
TEENS IN THE NORTH AND THE 20S FOR THE CENTRAL MTNS. A MODERATE
BREEZE WILL ONLY ADD TO THE CHILL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AFTER THE COLDEST AIR OF THE WINTER SEASON SETTLES OVER THE AREA
TUESDAY MORNING...QUIET WEATHER WILL RETURN AS WE START TO ENJOY
THE BENEFITS OF RAPIDLY BUILDING HEIGHTS ALOFT WITH THE RETURN OF THE
EASTERN RIDGE...FOR AT LEAST A FEW DAYS. MODERATING TEMPERATURES
WILL CONTINUE THROUGH THE EXTENDED PERIOD AFTER WE WILL THE WEEK
SEVERAL DEGREES COOLER THAN NORMAL BUT...BY MID TO LAKE
WEEK...THAT WILL REVERSE AND RETURN TO SEVERAL DEGREES WARMER THAN
NORMAL.
A COMPLEX STORM/FRONTAL SYSTEM WILL APPROACH FOR THE END OF THE
WEEK. LOW PRESSURE TRACK DIFFERS BETWEEN THE LONGER RANGE MODELS
AND THAT WILL AFFECT THE QPF. DOESN`T SEEM TO BE ENOUGH COLD AIR
IN THE CARDS TO GET EXCITED ABOUT THE PROSPECTS FOR BIG SNOW
HOWEVER.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
LOW CLOUDS CONTINUE TO PROGRESS SOUTHEASTWARD ACROSS CENTRAL
PA LATE THIS MORNING INTO THIS AFTN. WINDS ARE BECOMING GUSTY
ACROSS WRN TAF SITES.
A COLD FRONT WILL DROP SOUTHEASTWARD ACROSS CENTRAL PA THIS
AFTERNOON AND EVENING...ACCOMPANIED BY SCTD SNOW SHOWERS AND
POSSIBLY A FEW SQUALLS. BEHIND THE FRONT...LAKE-EFFECT AND
UPSLOPE SNOW SHOWERS WILL CONTINUE TO AFFECT PRIMARILY THE WRN
HIGHLANDS /KBFD AND KJST/ TONIGHT INTO EARLY MONDAY...ACCOMPANIED
BY REDUCED CIGS AND VSBYS.
HIGH PRESSURE WILL BUILD INTO THE AREA BY TUES AND PERSIST INTO
THURS.
OUTLOOK...
SUN NIGHT-MON...REDUCTIONS ACROSS WESTERN HIGHER TERRAIN IN SNOW
SHOWERS AND POTENTIAL SQUALLS. MVFR CIG REDUCTIONS CENTRAL MTNS.
MAINLY VFR SE. BREEZY.
TUE-THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE/EVANEGO
SHORT TERM...LA CORTE/EVANEGO
LONG TERM...LA CORTE
AVIATION...MARTIN/EVANEGO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
933 AM EST SUN JAN 3 2016
.SYNOPSIS...
NORTHWEST FLOW WILL CONTINUE TO DOMINATE THE PATTERN FOR THE NEXT
SEVERAL DAYS WITH THE COLDEST AIR OF THE SEASON EXPECTED TO START
THE FIRST FULL WEEK OF THE NEW YEAR. TEMPERATURES WILL BEGIN TO
MODERATE LATER IN THE WEEK AS HIGH PRESSURE BUILDS EASTWARD.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN ARCTIC FRONT WILL PASS SOUTHWARD ACROSS PENNSYLVANIA THIS
AFTERNOON INTO TONIGHT...AND THE LOW CLOUD SHIELD CONTINUES TO
MAKE PROGRESS SOUTHEASTWARD.
LATEST HRRR SHOWS SCATTERED SNOW SHOWERS REDEVELOPING DOWNWIND OF
LAKE ERIE INTO WARREN AND MCKEAN COUNTIES AND CONTINUING THROUGH
AT LEAST THE AFTERNOON HOURS.
THE BIG QUESTION IS TO WHAT EXTENT THE LAKE-EFFECT MACHINE CAN
GET CRANKED UP. MODEL SOUNDINGS DON`T REALLY SHOW A FAVORABLE
OVER-LAKE ALIGNMENT TAKING PLACE FOR MUCH MORE THAN A FEW HOURS
THIS AFTERNOON BEFORE POST-FRONTAL LOW LEVEL WINDS COME AROUND TO
A MORE NORTHERLY/SHORTER OVERLAKE TRAJECTORY AND OVERALL INVERSION
HEIGHTS START TO FALL LATER DURING THE EVENING AND OVERNIGHT.
STILL WITH THE LAKES BEING UNSEASONABLY WARM...THE INSTABILITY
SHOULD BE ENOUGH FOR THE NORMAL SNOW BELT AREAS TO SEE ANYWHERE
FROM A COATING TO A FEW INCHES. AT THIS TIME...I DON`T HAVE HIGH
ENOUGH CONFIDENCE THAT ADVISORY NUMBERS CAN BE MET IN A 12 HOUR
WINDOW TO WARRANT A WINTER WX HEADLINE.
IT LOOKS LIKE OROGRAPHICALLY-ENHANCED SNOWS WILL FOCUS INTO THE
LAURELS FOR A TIME OVERNIGHT INTO EARLY MONDAY. THE DRYNESS OF THE
UPSTREAM AIRMASS AND THE SHORT DURATION OF BEST ALIGNED FLOW
SHOULD SIMILARLY LIMIT ACCUMULATIONS TO MAINLY NUISANCE NUMBERS
THERE.
OVERNIGHT LOWS IN THE TEENS TO LOWER TWENTIES WILL FEEL COLD
COMPARED TO WHAT THE SEASON HAS HAD TO OFFER TO DATE...BUT WILL
ACTUALLY BE VERY NEAR NORMAL FOR EARLY JANUARY.
&&
.SHORT TERM /MONDAY/...
THE COLD FRONT THAT WILL PASS LATER TONIGHT AND TURN THE WINDS
FLOW TO A MORE NORTHERLY TRAJECTORY...BRINGING IN THE COLDEST AIR
OF THE SEASON TO DATE.
850MB TEMPS OVER NRN PA WILL BE IN THE NEIGHBORHOOD OF -20C BY
MONDAY AFTERNOON...WHICH HAS NOT BEEN SEEN SINCE LAST WINTER.
AS THE SURFACE HIGH BULGES EAST AND THE UPPER TROUGH STARTS
LIFTING OUT...SNOW SHOWER ACTIVITY SHOULD BEGIN TO TAPER OFF
THROUGH THE DAY ON MONDAY.
WE ARE IN FOR A DEFINITE JANUARY-FEELING DAY ON MONDAY...WITH
TEMPS NOT RISING MUCH FOR MOST AREAS. HIGHS WILL HOLD IN THE
TEENS IN THE NORTH AND THE 20S FOR THE CENTRAL MTNS. A MODERATE
BREEZE WILL ONLY ADD TO THE CHILL.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AFTER THE COLDEST AIR OF THE WINTER SEASON SETTLES OVER THE AREA
TUESDAY MORNING...QUIET WEATHER WILL RETURN AS WE START TO ENJOY
THE BENEFITS OF RAPIDLY BUILDING HEIGHTS ALOFT WITH THE RETURN OF THE
EASTERN RIDGE...FOR AT LEAST A FEW DAYS. MODERATING TEMPERATURES
WILL CONTINUE THROUGH THE EXTENDED PERIOD AFTER WE WILL THE WEEK
SEVERAL DEGREES COOLER THAN NORMAL BUT...BY MID TO LAKE
WEEK...THAT WILL REVERSE AND RETURN TO SEVERAL DEGREES WARMER THAN
NORMAL.
A COMPLEX STORM/FRONTAL SYSTEM WILL APPROACH FOR THE END OF THE
WEEK. LOW PRESSURE TRACK DIFFERS BETWEEN THE LONGER RANGE MODELS
AND THAT WILL AFFECT THE QPF. DOESN`T SEEM TO BE ENOUGH COLD AIR
IN THE CARDS TO GET EXCITED ABOUT THE PROSPECTS FOR BIG SNOW
HOWEVER.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
JUST SOME MINOR ADJUSTMENTS TO THE 12Z TAFS.
CLOUD LINE JUST NORTH OF THE OFFICE NOW.
12Z TAFS SENT.
EARLIER DISCUSSION BELOW.
MADE SOME CHANGES TO THE TAF PACKAGE ON THE 09Z TAF UPDATE.
GUSTY WINDS ACROSS THE WEST AND CENTRAL AREAS.
MAIN THING IS THE SHARP EDGE OF THE CLOUDS INTO BFD. DID SLOW
DOWN HOW FAST THE CLDS MAKE IT FURTHER S AND E.
RATHER STRONG WIND MAX AND COLD FRONT WILL DROP SE THIS AFTERNOON
AND EVENING. NOT REALLY THE RIGHT CONDITIONS FOR LAKE EFFECT...BUT
A BRIEF PERIOD OF SNOW COULD OCCUR ALONG AND JUST BEHIND THE COLD
FRONT...ESPECIALLY AT BFD AND JST. THE AIRMASS BEHIND THE FRONT IS
QUITE DRY...SO ANY HEAVIER SNOW WOULD NOT LAST LONG. LIGHT SNOW
COULD LINGER ACROSS THE WESTERN AREAS UNTIL LUNCH TIME ON MONDAY.
HIGH PRESSURE WILL BUILD INTO THE AREA ON TUE AND LINGER INTO THU.
OUTLOOK...
SUN NIGHT-MON...REDUCTIONS ACROSS WESTERN HIGHER TERRAIN IN SNOW
SHOWERS AND POTENTIAL SCT SQUALLS. MAINLY CIG REDUCTIONS CENTRAL
MTNS. MAINLY VFR SE. BREEZY.
TUE-THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE/EVANEGO
SHORT TERM...LA CORTE/EVANEGO
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
713 AM EST SUN JAN 3 2016
.SYNOPSIS...
NORTHWEST FLOW WILL CONTINUE TO DOMINATE THE PATTERN FOR THE NEXT
SEVERAL DAYS WITH THE COLDEST AIR OF THE SEASON EXPECTED TO START
THE FIRST FULL WEEK OF THE NEW YEAR. TEMPERATURES WILL BEGIN TO
MODERATE LATER IN THE WEEK AS HIGH PRESSURE BUILDS EASTWARD.
&&
.NEAR TERM /THROUGH TONIGHT/...
6AM UPDATE...
LOW CLOUD SHIELD MAKING SMART PROGRESS SOUTHEAST. TWEAKED
CLOUDCOVER FORECAST UP A BIT...BUT NO MAJOR CHANGES MADE.
LATEST HRRR SHOWS SCATTERED LIGHT SNOW SHOWERS REDEVELOPING
DOWNWIND OF LAKE ERIE INTO WARREN AND MCKEAN COUNTIES BY AROUND
SUNRISE...THEN WITH DISORGANIZED ACTIVITY CONTINUING THROUGH AT
LEAST THE AFTERNOON HOURS.
THE ARCTIC FRONT KIND OF GETS LOST IN THE MODEL
DERIVED ISOBARS...BUT LOOKING AT 850 TEMPS SHOWS IT SHOULD BE
PASSING THROUGH SOUTHERN PA JUST AFTER MIDNIGHT.
THE BIG QUESTION IS TO WHAT EXTENT THE LAKE EFFECT MACHINE CAN GET
CRANKED UP. MODEL SOUNDINGS DON`T REALLY SHOW A FAVORABLE OVER-
LAKE ALIGNMENT TAKING PLACE FOR MUCH MORE THAN A FEW HOURS THIS
AFTERNOON BEFORE POST FRONTAL LOW LEVEL WINDS COME AROUND TO A
MORE NORTHERLY/SHORTER OVERLAKE TRAJECTORY AND OVERALL INVERSION
HEIGHTS START TO FALL LATER DURING THE EVENING AND OVERNIGHT.
STILL WITH THE LAKES BEING UNSEASONABLY WARM...THE INSTABILITY
SHOULD BE ENOUGH FOR THE NORMAL SNOW BELT AREAS TO SEE ANYWHERE
FROM A COATING TO A FEW INCHES...BUT AT THIS TIME I DON`T HAVE
HIGH ENOUGH CONFIDENCE THAT ADVISORY NUMBERS CAN BE MET IN A 12
HOUR WINDOW TO WARRANT A HEADLINE.
A BETTER CHANCE SEEMS TO EXIST FOR OROGRAPHICALLY ENHANCED SNOWS
TO FOCUS INTO THE LAURELS FOR A TIME OVERNIGHT INTO EARLY MONDAY.
THE DRYNESS OF THE UPSTREAM AIRMASS AND THE SHORT DURATION OF BEST
ALIGNED FLOW SHOULD SIMILARLY LIMIT ACCUMULATIONS TO MAINLY
NUISANCE NUMBERS THERE.
OVERNIGHT LOWS IN THE TEENS TO LOWER TWENTIES WILL FEEL COLD
COMPARED TO WHAT THE SEASON HAS HAD TO OFFER TO DATE...BUT WILL
ACTUALLY BE VERY NEAR NORMAL FOR EARLY JANUARY.
&&
.SHORT TERM /MONDAY/...
THE COLD FRONT THAT WILL PASS LATER TONIGHT AND TURN THE WINDS
FLOW TO A MORE NORTHERLY TRAJECTORY BRINGING IN THE COLDEST AIR OF
THE SEASON TO DATE.
850MB TEMPS OVER MUCH OF THE NORTH IN THE NEIGHBORHOOD OF AROUND
-20C BY MONDAY AFTERNOON HAVE NOT BEEN SEEN SINCE THE BITTER
CHILL OF LAST WINTER.
AS THE SURFACE HIGH BULGES EAST AND THE UPPER TROUGH STARTS
LIFTING OUT...SNOW SHOWER ACTIVITY SHOULD BEGIN TO TAPER OFF THE
DEEPER INTO THE DAY MONDAY WE GO.
WE ARE IN FOR A DEFINITE JANUARY-FEELING DAY ON MONDAY WITH TEMPS
NOT RISING MUCH FOR MOST AREAS...STICKING IN THE TEENS IN THE
NORTH AND 20S FOR THE CENTRAL MTNS. A MODERATE BREEZE WILL ADD TO
THE CHILL THAT GREETS THE KIDDIES RETURNING FROM CHRISTMAS
VACATION.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AFTER THE COLDEST AIR OF THE WINTER SEASON SETTLES OVER THE AREA
TUESDAY MORNING...QUIET WEATHER WILL RETURN AS WE START TO ENJOY
THE BENEFITS OF RAPIDLY BUILDING HEIGHTS ALOFT WITH THE RETURN OF THE
EASTERN RIDGE...FOR AT LEAST A FEW DAYS. MODERATING TEMPERATURES
WILL CONTINUE THROUGH THE EXTENDED PERIOD AFTER WE WILL THE WEEK
SEVERAL DEGREES COOLER THAN NORMAL BUT...BY MID TO LAKE
WEEK...THAT WILL REVERSE AND RETURN TO SEVERAL DEGREES WARMER THAN
NORMAL.
A COMPLEX STORM/FRONTAL SYSTEM WILL APPROACH FOR THE END OF THE
WEEK. LOW PRESSURE TRACK DIFFERS BETWEEN THE LONGER RANGE MODELS
AND THAT WILL AFFECT THE QPF. DOESN`T SEEM TO BE ENOUGH COLD AIR
IN THE CARDS TO GET EXCITED ABOUT THE PROSPECTS FOR BIG SNOW
HOWEVER.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
JUST SOME MINOR ADJUSTMENTS TO THE 12Z TAFS.
CLOUD LINE JUST NORTH OF THE OFFICE NOW.
12Z TAFS SENT.
EARLIER DISCUSSION BELOW.
MADE SOME CHANGES TO THE TAF PACKAGE ON THE 09Z TAF UPDATE.
GUSTY WINDS ACROSS THE WEST AND CENTRAL AREAS.
MAIN THING IS THE SHARP EDGE OF THE CLOUDS INTO BFD. DID SLOW
DOWN HOW FAST THE CLDS MAKE IT FURTHER S AND E.
RATHER STRONG WIND MAX AND COLD FRONT WILL DROP SE THIS AFTERNOON
AND EVENING. NOT REALLY THE RIGHT CONDITIONS FOR LAKE EFFECT...BUT
A BRIEF PERIOD OF SNOW COULD OCCUR ALONG AND JUST BEHIND THE COLD
FRONT...ESPECIALLY AT BFD AND JST. THE AIRMASS BEHIND THE FRONT IS
QUITE DRY...SO ANY HEAVIER SNOW WOULD NOT LAST LONG. LIGHT SNOW
COULD LINGER ACROSS THE WESTERN AREAS UNTIL LUNCH TIME ON MONDAY.
HIGH PRESSURE WILL BUILD INTO THE AREA ON TUE AND LINGER INTO THU.
OUTLOOK...
SUN NIGHT-MON...REDUCTIONS ACROSS WESTERN HIGHER TERRAIN IN SNOW
SHOWERS AND POTENTIAL SCT SQUALLS. MAINLY CIG REDUCTIONS CENTRAL
MTNS. MAINLY VFR SE. BREEZY.
TUE-THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
621 AM EST SUN JAN 3 2016
.SYNOPSIS...
NORTHWEST FLOW WILL CONTINUE TO DOMINATE THE PATTERN FOR THE NEXT
SEVERAL DAYS WITH THE COLDEST AIR OF THE SEASON EXPECTED TO START
THE FIRST FULL WEEK OF THE NEW YEAR. TEMPERATURES WILL BEGIN TO
MODERATE LATER IN THE WEEK AS HIGH PRESSURE BUILDS EASTWARD.
&&
.NEAR TERM /THROUGH TONIGHT/...
6AM UPDATE...
LOW CLOUD SHIELD MAKING SMART PROGRESS SOUTHEAST. TWEAKED
CLOUDCOVER FORECAST UP A BIT...BUT NO MAJOR CHANGES MADE.
LATEST HRRR SHOWS SCATTERED LIGHT SNOW SHOWERS REDEVELOPING
DOWNWIND OF LAKE ERIE INTO WARREN AND MCKEAN COUNTIES BY AROUND
SUNRISE...THEN WITH DISORGANIZED ACTIVITY CONTINUING THROUGH AT
LEAST THE AFTERNOON HOURS.
THE ARCTIC FRONT KIND OF GETS LOST IN THE MODEL
DERIVED ISOBARS...BUT LOOKING AT 850 TEMPS SHOWS IT SHOULD BE
PASSING THROUGH SOUTHERN PA JUST AFTER MIDNIGHT.
THE BIG QUESTION IS TO WHAT EXTENT THE LAKE EFFECT MACHINE CAN GET
CRANKED UP. MODEL SOUNDINGS DON`T REALLY SHOW A FAVORABLE OVER-
LAKE ALIGNMENT TAKING PLACE FOR MUCH MORE THAN A FEW HOURS THIS
AFTERNOON BEFORE POST FRONTAL LOW LEVEL WINDS COME AROUND TO A
MORE NORTHERLY/SHORTER OVERLAKE TRAJECTORY AND OVERALL INVERSION
HEIGHTS START TO FALL LATER DURING THE EVENING AND OVERNIGHT.
STILL WITH THE LAKES BEING UNSEASONABLY WARM...THE INSTABILITY
SHOULD BE ENOUGH FOR THE NORMAL SNOW BELT AREAS TO SEE ANYWHERE
FROM A COATING TO A FEW INCHES...BUT AT THIS TIME I DON`T HAVE
HIGH ENOUGH CONFIDENCE THAT ADVISORY NUMBERS CAN BE MET IN A 12
HOUR WINDOW TO WARRANT A HEADLINE.
A BETTER CHANCE SEEMS TO EXIST FOR OROGRAPHICALLY ENHANCED SNOWS
TO FOCUS INTO THE LAURELS FOR A TIME OVERNIGHT INTO EARLY MONDAY.
THE DRYNESS OF THE UPSTREAM AIRMASS AND THE SHORT DURATION OF BEST
ALIGNED FLOW SHOULD SIMILARLY LIMIT ACCUMULATIONS TO MAINLY
NUISANCE NUMBERS THERE.
OVERNIGHT LOWS IN THE TEENS TO LOWER TWENTIES WILL FEEL COLD
COMPARED TO WHAT THE SEASON HAS HAD TO OFFER TO DATE...BUT WILL
ACTUALLY BE VERY NEAR NORMAL FOR EARLY JANUARY.
&&
.SHORT TERM /MONDAY/...
THE COLD FRONT THAT WILL PASS LATER TONIGHT AND TURN THE WINDS
FLOW TO A MORE NORTHERLY TRAJECTORY BRINGING IN THE COLDEST AIR OF
THE SEASON TO DATE.
850MB TEMPS OVER MUCH OF THE NORTH IN THE NEIGHBORHOOD OF AROUND
-20C BY MONDAY AFTERNOON HAVE NOT BEEN SEEN SINCE THE BITTER
CHILL OF LAST WINTER.
AS THE SURFACE HIGH BULGES EAST AND THE UPPER TROUGH STARTS
LIFTING OUT...SNOW SHOWER ACTIVITY SHOULD BEGIN TO TAPER OFF THE
DEEPER INTO THE DAY MONDAY WE GO.
WE ARE IN FOR A DEFINITE JANUARY-FEELING DAY ON MONDAY WITH TEMPS
NOT RISING MUCH FOR MOST AREAS...STICKING IN THE TEENS IN THE
NORTH AND 20S FOR THE CENTRAL MTNS. A MODERATE BREEZE WILL ADD TO
THE CHILL THAT GREETS THE KIDDIES RETURNING FROM CHRISTMAS
VACATION.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AFTER THE COLDEST AIR OF THE WINTER SEASON SETTLES OVER THE AREA
TUESDAY MORNING...QUIET WEATHER WILL RETURN AS WE START TO ENJOY
THE BENEFITS OF RAPIDLY BUILDING HEIGHTS ALOFT WITH THE RETURN OF THE
EASTERN RIDGE...FOR AT LEAST A FEW DAYS. MODERATING TEMPERATURES
WILL CONTINUE THROUGH THE EXTENDED PERIOD AFTER WE WILL THE WEEK
SEVERAL DEGREES COOLER THAN NORMAL BUT...BY MID TO LAKE
WEEK...THAT WILL REVERSE AND RETURN TO SEVERAL DEGREES WARMER THAN
NORMAL.
A COMPLEX STORM/FRONTAL SYSTEM WILL APPROACH FOR THE END OF THE
WEEK. LOW PRESSURE TRACK DIFFERS BETWEEN THE LONGER RANGE MODELS
AND THAT WILL AFFECT THE QPF. DOESN`T SEEM TO BE ENOUGH COLD AIR
IN THE CARDS TO GET EXCITED ABOUT THE PROSPECTS FOR BIG SNOW
HOWEVER.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
MADE SOME CHANGES TO THE TAF PACKAGE ON THE 09Z TAF UPDATE.
GUSTY WINDS ACROSS THE WEST AND CENTRAL AREAS.
MAIN THING IS THE SHARP EDGE OF THE CLOUDS INTO BFD. DID SLOW
DOWN HOW FAST THE CLDS MAKE IT FURTHER S AND E.
RATHER STRONG WIND MAX AND COLD FRONT WILL DROP SE THIS AFTERNOON
AND EVENING. NOT REALLY THE RIGHT CONDITIONS FOR LAKE EFFECT...BUT
A BRIEF PERIOD OF SNOW COULD OCCUR ALONG AND JUST BEHIND THE COLD
FRONT...ESPECIALLY AT BFD AND JST. THE AIRMASS BEHIND THE FRONT IS
QUITE DRY...SO ANY HEAVIER SNOW WOULD NOT LAST LONG. LIGHT SNOW
COULD LINGER ACROSS THE WESTERN AREAS UNTIL LUNCH TIME ON MONDAY.
HIGH PRESSURE WILL BUILD INTO THE AREA ON TUE AND LINGER INTO THU.
OUTLOOK...
SUN NIGHT-MON...REDUCTIONS ACROSS WESTERN HIGHER TERRAIN IN SNOW
SHOWERS AND POTENTIAL SCT SQUALLS. MAINLY CIG REDUCTIONS CENTRAL
MTNS. MAINLY VFR SE. BREEZY.
TUE-THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
520 AM EST SUN JAN 3 2016
.SYNOPSIS...
NORTHWEST FLOW WILL CONTINUE TO DOMINATE THE PATTERN FOR THE NEXT
SEVERAL DAYS WITH THE COLDEST AIR OF THE SEASON EXPECTED TO START
THE FIRST FULL WEEK OF THE NEW YEAR. TEMPERATURES WILL BEGIN TO
MODERATE LATER IN THE WEEK AS HIGH PRESSURE BUILDS EASTWARD.
&&
.NEAR TERM /THROUGH TONIGHT/...
SKIES ARE CLEAR ACROSS THE REGION...BUT THE ARRIVAL OF A NEW
SHIELD OF LOW CLOUDS WILL SOON BE FELT OVER THE NW MOUNTAINS AS
MOISTURE FROM A WEAK SURFACE TROUGH INTERACTING WITH THE GREAT
LAKES WILL BRING THE CLOUDS RAPIDLY SOUTHEAST BACK INTO THE
REGION.
LATEST HRRR SHOWS SCATTERED LIGHT SNOW SHOWERS REDEVELOPING
DOWNWIND OF LAKE ERIE INTO WARREN AND MCKEAN COUNTIES BY AROUND
SUNRISE...THEN WITH DISORGANIZED ACTIVITY CONTINUING THROUGH AT
LEAST THE AFTERNOON HOURS.
THE ARCTIC FRONT KIND OF GETS LOST IN THE MODEL
DERIVED ISOBARS...BUT LOOKING AT 850 TEMPS SHOWS IT SHOULD BE
PASSING THROUGH SOUTHERN PA JUST AFTER MIDNIGHT.
THE BIG QUESTION IS TO WHAT EXTENT THE LAKE EFFECT MACHINE CAN GET
CRANKED UP. MODEL SOUNDINGS DON`T REALLY SHOW A FAVORABLE OVER-
LAKE ALIGNMENT TAKING PLACE FOR MUCH MORE THAN A FEW HOURS THIS
AFTERNOON BEFORE POST FRONTAL LOW LEVEL WINDS COME AROUND TO A
MORE NORTHERLY/SHORTER OVERLAKE TRAJECTORY AND OVERALL INVERSION
HEIGHTS START TO FALL LATER DURING THE EVENING AND OVERNIGHT.
STILL WITH THE LAKES BEING UNSEASONABLY WARM...THE INSTABILITY
SHOULD BE ENOUGH FOR THE NORMAL SNOW BELT AREAS TO SEE ANYWHERE
FROM A COATING TO A FEW INCHES...BUT AT THIS TIME I DON`T HAVE
HIGH ENOUGH CONFIDENCE THAT ADVISORY NUMBERS CAN BE MET IN A 12
HOUR WINDOW TO WARRANT A HEADLINE.
A BETTER CHANCE SEEMS TO EXIST FOR OROGRAPHICALLY ENHANCED SNOWS
TO FOCUS INTO THE LAURELS FOR A TIME OVERNIGHT INTO EARLY MONDAY.
THE DRYNESS OF THE UPSTREAM AIRMASS AND THE SHORT DURATION OF BEST
ALIGNED FLOW SHOULD SIMILARLY LIMIT ACCUMULATIONS TO MAINLY
NUISANCE NUMBERS THERE.
OVERNIGHT LOWS IN THE TEENS TO LOWER TWENTIES WILL FEEL COLD
COMPARED TO WHAT THE SEASON HAS HAD TO OFFER TO DATE...BUT WILL
ACTUALLY BE VERY NEAR NORMAL FOR EARLY JANUARY.
&&
.SHORT TERM /MONDAY/...
THE COLD FRONT THAT WILL PASS LATER TONIGHT AND TURN THE WINDS
FLOW TO A MORE NORTHERLY TRAJECTORY BRINGING IN THE COLDEST AIR OF
THE SEASON TO DATE.
850MB TEMPS OVER MUCH OF THE NORTH IN THE NEIGHBORHOOD OF AROUND
-20C BY MONDAY AFTERNOON HAVE NOT BEEN SEEN SINCE THE BITTER
CHILL OF LAST WINTER.
AS THE SURFACE HIGH BULGES EAST AND THE UPPER TROUGH STARTS
LIFTING OUT...SNOW SHOWER ACTIVITY SHOULD BEGIN TO TAPER OFF THE
DEEPER INTO THE DAY MONDAY WE GO.
WE ARE IN FOR A DEFINITE JANUARY-FEELING DAY ON MONDAY WITH TEMPS
NOT RISING MUCH FOR MOST AREAS...STICKING IN THE TEENS IN THE
NORTH AND 20S FOR THE CENTRAL MTNS. A MODERATE BREEZE WILL ADD TO
THE CHILL THAT GREETS THE KIDDIES RETURNING FROM CHRISTMAS
VACATION.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AFTER THE COLDEST AIR OF THE WINTER SEASON SETTLES OVER THE AREA
TUESDAY MORNING...QUIET WEATHER WILL RETURN AS WE START TO ENJOY
THE BENEFITS OF RAPIDLY BUILDING HEIGHTS ALOFT WITH THE RETURN OF THE
EASTERN RIDGE...FOR AT LEAST A FEW DAYS. MODERATING TEMPERATURES
WILL CONTINUE THROUGH THE EXTENDED PERIOD AFTER WE WILL THE WEEK
SEVERAL DEGREES COOLER THAN NORMAL BUT...BY MID TO LAKE
WEEK...THAT WILL REVERSE AND RETURN TO SEVERAL DEGREES WARMER THAN
NORMAL.
A COMPLEX STORM/FRONTAL SYSTEM WILL APPROACH FOR THE END OF THE
WEEK. LOW PRESSURE TRACK DIFFERS BETWEEN THE LONGER RANGE MODELS
AND THAT WILL AFFECT THE QPF. DOESN`T SEEM TO BE ENOUGH COLD AIR
IN THE CARDS TO GET EXCITED ABOUT THE PROSPECTS FOR BIG SNOW
HOWEVER.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
MADE SOME CHANGES TO THE TAF PACKAGE ON THE 09Z TAF UPDATE.
GUSTY WINDS ACROSS THE WEST AND CENTRAL AREAS.
MAIN THING IS THE SHARP EDGE OF THE CLOUDS INTO BFD. DID SLOW
DOWN HOW FAST THE CLDS MAKE IT FURTHER S AND E.
RATHER STRONG WIND MAX AND COLD FRONT WILL DROP SE THIS AFTERNOON
AND EVENING. NOT REALLY THE RIGHT CONDITIONS FOR LAKE EFFECT...BUT
A BRIEF PERIOD OF SNOW COULD OCCUR ALONG AND JUST BEHIND THE COLD
FRONT...ESPECIALLY AT BFD AND JST. THE AIRMASS BEHIND THE FRONT IS
QUITE DRY...SO ANY HEAVIER SNOW WOULD NOT LAST LONG. LIGHT SNOW
COULD LINGER ACROSS THE WESTERN AREAS UNTIL LUNCH TIME ON MONDAY.
HIGH PRESSURE WILL BUILD INTO THE AREA ON TUE AND LINGER INTO THU.
OUTLOOK...
SUN NIGHT-MON...REDUCTIONS ACROSS WESTERN HIGHER TERRAIN IN SNOW
SHOWERS AND POTENTIAL SCT SQUALLS. MAINLY CIG REDUCTIONS CENTRAL
MTNS. MAINLY VFR SE. BREEZY.
TUE-THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
514 AM EST SUN JAN 3 2016
.SYNOPSIS...
NORTHWEST FLOW WILL CONTINUE TO DOMINATE THE PATTERN FOR THE NEXT
SEVERAL DAYS WITH THE COLDEST AIR OF THE SEASON EXPECTED TO START
THE FIRST FULL WEEK OF THE NEW YEAR. TEMPERATURES WILL BEGIN TO
MODERATE LATER IN THE WEEK AS HIGH PRESSURE BUILDS EASTWARD.
&&
.NEAR TERM /THROUGH TONIGHT/...
SKIES ARE CLEAR ACROSS THE REGION...BUT THE ARRIVAL OF A NEW
SHIELD OF LOW CLOUDS WILL SOON BE FELT OVER THE NW MOUNTAINS AS
MOISTURE FROM A WEAK SURFACE TROUGH INTERACTING WITH THE GREAT
LAKES WILL BRING THE CLOUDS RAPIDLY SOUTHEAST BACK INTO THE
REGION.
LATEST HRRR SHOWS SCATTERED LIGHT SNOW SHOWERS REDEVELOPING
DOWNWIND OF LAKE ERIE INTO WARREN AND MCKEAN COUNTIES BY AROUND
SUNRISE...THEN WITH DISORGANIZED ACTIVITY CONTINUING THROUGH AT
LEAST THE AFTERNOON HOURS.
THE ARCTIC FRONT KIND OF GETS LOST IN THE MODEL
DERIVED ISOBARS...BUT LOOKING AT 850 TEMPS SHOWS IT SHOULD BE
PASSING THROUGH SOUTHERN PA JUST AFTER MIDNIGHT.
THE BIG QUESTION IS TO WHAT EXTENT THE LAKE EFFECT MACHINE CAN GET
CRANKED UP. MODEL SOUNDINGS DON`T REALLY SHOW A FAVORABLE OVER-
LAKE ALIGNMENT TAKING PLACE FOR MUCH MORE THAN A FEW HOURS THIS
AFTERNOON BEFORE POST FRONTAL LOW LEVEL WINDS COME AROUND TO A
MORE NORTHERLY/SHORTER OVERLAKE TRAJECTORY AND OVERALL INVERSION
HEIGHTS START TO FALL LATER DURING THE EVENING AND OVERNIGHT.
STILL WITH THE LAKES BEING UNSEASONABLY WARM...THE INSTABILITY
SHOULD BE ENOUGH FOR THE NORMAL SNOW BELT AREAS TO SEE ANYWHERE
FROM A COATING TO A FEW INCHES...BUT AT THIS TIME I DON`T HAVE
HIGH ENOUGH CONFIDENCE THAT ADVISORY NUMBERS CAN BE MET IN A 12
HOUR WINDOW TO WARRANT A HEADLINE.
A BETTER CHANCE SEEMS TO EXIST FOR OROGRAPHICALLY ENHANCED SNOWS
TO FOCUS INTO THE LAURELS FOR A TIME OVERNIGHT INTO EARLY MONDAY.
THE DRYNESS OF THE UPSTREAM AIRMASS AND THE SHORT DURATION OF BEST
ALIGNED FLOW SHOULD SIMILARLY LIMIT ACCUMULATIONS TO MAINLY
NUISANCE NUMBERS THERE.
OVERNIGHT LOWS IN THE TEENS TO LOWER TWENTIES WILL FEEL COLD
COMPARED TO WHAT THE SEASON HAS HAD TO OFFER TO DATE...BUT WILL
ACTUALLY BE VERY NEAR NORMAL FOR EARLY JANUARY.
&&
.SHORT TERM /MONDAY/...
THE COLD FRONT THAT WILL PASS LATER TONIGHT AND TURN THE WINDS
FLOW TO A MORE NORTHERLY TRAJECTORY BRINGING IN THE COLDEST AIR OF
THE SEASON TO DATE.
850MB TEMPS OVER MUCH OF THE NORTH IN THE NEIGHBORHOOD OF AROUND
-20C BY MONDAY AFTERNOON HAVE NOT BEEN SEEN SINCE THE BITTER
CHILL OF LAST WINTER.
AS THE SURFACE HIGH BULGES EAST AND THE UPPER TROUGH STARTS
LIFTING OUT...SNOW SHOWER ACTIVITY SHOULD BEGIN TO TAPER OFF THE
DEEPER INTO THE DAY MONDAY WE GO.
WE ARE IN FOR A DEFINITE JANUARY-FEELING DAY ON MONDAY WITH TEMPS
NOT RISING MUCH FOR MOST AREAS...STICKING IN THE TEENS IN THE
NORTH AND 20S FOR THE CENTRAL MTNS. A MODERATE BREEZE WILL ADD TO
THE CHILL THAT GREETS THE KIDDIES RETURNING FROM CHRISTMAS
VACATION.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AFTER THE COLDEST AIR OF THE WINTER SEASON SETTLES OVER THE AREA
TUESDAY MORNING...QUIET WEATHER WILL RETURN AS WE START TO ENJOY
THE BENEFITS OF RAPIDLY BUILDING HEIGHTS ALOFT WITH THE RETURN OF THE
EASTERN RIDGE...FOR AT LEAST A FEW DAYS. MODERATING TEMPERATURES
WILL CONTINUE THROUGH THE EXTENDED PERIOD AFTER WE WILL THE WEEK
SEVERAL DEGREES COOLER THAN NORMAL BUT...BY MID TO LAKE
WEEK...THAT WILL REVERSE AND RETURN TO SEVERAL DEGREES WARMER THANNORMAL.
A COMPLEX STORM/FRONTAL SYSTEM WILL APPROACH FOR THE END OF THE
WEEK. LOW PRESSURE TRACK DIFFERS BETWEEN THE LONGER RANGE MODELS
AND THAT WILL AFFECT THE QPF. DOESN`T SEEM TO BE ENOUGH COLD AIR
IN THE CARDS TO GET EXCITED ABOUT THE PROSPECTS FOR BIG SNOW
HOWEVER.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
MADE SOME CHANGES TO THE TAF PACKAGE ON THE 09Z TAF UPDATE.
GUSTY WINDS ACROSS THE WEST AND CENTRAL AREAS.
MAIN THING IS THE SHARP EDGE OF THE CLOUDS INTO BFD. DID SLOW
DOWN HOW FAST THE CLDS MAKE IT FURTHER S AND E.
RATHER STRONG WIND MAX AND COLD FRONT WILL DROP SE THIS AFTERNOON
AND EVENING. NOT REALLY THE RIGHT CONDITIONS FOR LAKE EFFECT...BUT
A BRIEF PERIOD OF SNOW COULD OCCUR ALONG AND JUST BEHIND THE COLD
FRONT...ESPECIALLY AT BFD AND JST. THE AIRMASS BEHIND THE FRONT IS
QUITE DRY...SO ANY HEAVIER SNOW WOULD NOT LAST LONG. LIGHT SNOW
COULD LINGER ACROSS THE WESTERN AREAS UNTIL LUNCH TIME ON MONDAY.
HIGH PRESSURE WILL BUILD INTO THE AREA ON TUE AND LINGER INTO THU.
OUTLOOK...
SUN NIGHT-MON...REDUCTIONS ACROSS WESTERN HIGHER TERRAIN IN SNOW
SHOWERS AND POTENTIAL SCT SQUALLS. MAINLY CIG REDUCTIONS CENTRAL
MTNS. MAINLY VFR SE. BREEZY.
TUE-THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
457 AM EST SUN JAN 3 2016
.SYNOPSIS...
NORTHWEST FLOW WILL CONTINUE TO DOMINATE THE PATTERN FOR THE NEXT
SEVERAL DAYS WITH THE COLDEST AIR OF THE SEASON EXPECTED TO START
THE FIRST FULL WEEK OF THE NEW YEAR. TEMPERATURES WILL BEGIN TO
MODERATE LATER IN THE WEEK AS HIGH PRESSURE BUILDS EASTWARD.
&&
.NEAR TERM /THROUGH TONIGHT/...
SKIES ARE CLEAR ACROSS THE REGION...BUT THE ARRIVAL OF A NEW
SHIELD OF LOW CLOUDS WILL SOON BE FELT OVER THE NW MOUNTAINS AS
MOISTURE FROM A WEAK SURFACE TROUGH INTERACTING WITH THE GREAT
LAKES WILL BRING THE CLOUDS RAPIDLY SOUTHEAST BACK INTO THE
REGION.
LATEST HRRR SHOWS SCATTERED LIGHT SNOW SHOWERS REDEVELOPING
DOWNWIND OF LAKE ERIE INTO WARREN AND MCKEAN COUNTIES BY AROUND
SUNRISE...THEN WITH DISORGANIZED ACTIVITY CONTINUING THROUGH AT
LEAST THE AFTERNOON HOURS.
THE ARCTIC FRONT KIND OF GETS LOST IN THE MODEL
DERIVED ISOBARS...BUT LOOKING AT 850 TEMPS SHOWS IT SHOULD BE
PASSING THROUGH SOUTHERN PA JUST AFTER MIDNIGHT.
THE BIG QUESTION IS TO WHAT EXTENT THE LAKE EFFECT MACHINE CAN GET
CRANKED UP. MODEL SOUNDINGS DON`T REALLY SHOW A FAVORABLE OVER-
LAKE ALIGNMENT TAKING PLACE FOR MUCH MORE THAN A FEW HOURS THIS
AFTERNOON BEFORE POST FRONTAL LOW LEVEL WINDS COME AROUND TO A
MORE NORTHERLY/SHORTER OVERLAKE TRAJECTORY AND OVERALL INVERSION
HEIGHTS START TO FALL LATER DURING THE EVENING AND OVERNIGHT.
STILL WITH THE LAKES BEING UNSEASONABLY WARM...THE INSTABILITY
SHOULD BE ENOUGH FOR THE NORMAL SNOW BELT AREAS TO SEE ANYWHERE
FROM A COATING TO A FEW INCHES...BUT AT THIS TIME I DON`T HAVE
HIGH ENOUGH CONFIDENCE THAT ADVISORY NUMBERS CAN BE MET IN A 12
HOUR WINDOW TO WARRANT A HEADLINE.
A BETTER CHANCE SEEMS TO EXIST FOR OROGRAPHICALLY ENHANCED SNOWS
TO FOCUS INTO THE LAURELS FOR A TIME OVERNIGHT INTO EARLY MONDAY.
THE DRYNESS OF THE UPSTREAM AIRMASS AND THE SHORT DURATION OF BEST
ALIGNED FLOW SHOULD SIMILARLY LIMIT ACCUMULATIONS TO MAINLY
NUISANCE NUMBERS THERE.
OVERNIGHT LOWS IN THE TEENS TO LOWER TWENTIES WILL FEEL COLD
COMPARED TO WHAT THE SEASON HAS HAD TO OFFER TO DATE...BUT WILL
ACTUALLY BE VERY NEAR NORMAL FOR EARLY JANUARY.
&&
.SHORT TERM /MONDAY/...
THE COLD FRONT THAT WILL PASS LATER TONIGHT AND TURN THE WINDS
FLOW TO A MORE NORTHERLY TRAJECTORY BRINGING IN THE COLDEST AIR OF
THE SEASON TO DATE.
850MB TEMPS OVER MUCH OF THE NORTH IN THE NEIGHBORHOOD OF AROUND
-20C BY MONDAY AFTERNOON HAVE NOT BEEN SEEN SINCE THE BITTER
CHILL OF LAST WINTER.
AS THE SURFACE HIGH BULGES EAST AND THE UPPER TROUGH STARTS
LIFTING OUT...SNOW SHOWER ACTIVITY SHOULD BEGIN TO TAPER OFF THE
DEEPER INTO THE DAY MONDAY WE GO.
WE ARE IN FOR A DEFINITE JANUARY-FEELING DAY ON MONDAY WITH TEMPS
NOT RISING MUCH FOR MOST AREAS...STICKING IN THE TEENS IN THE
NORTH AND 20S FOR THE CENTRAL MTNS. A MODERATE BREEZE WILL ADD TO
THE CHILL THAT GREETS THE KIDDIES RETURNING FROM CHRISTMAS
VACATION.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
AFTER THE COLDEST AIR OF THE WINTER SEASON SETTLES OVER THE AREA
TUESDAY MORNING...QUIET WEATHER WILL RETURN AS WE START TO ENJOY
THE BENEFITS OF RAPIDLY BUILDING HEIGHTS ALOFT WITH THE RETURN OF THE
EASTERN RIDGE...FOR AT LEAST A FEW DAYS. MODERATING TEMPERATURES
WILL CONTINUE THROUGH THE EXTENDED PERIOD AFTER WE WILL THE WEEK
SEVERAL DEGREES COOLER THAN NORMAL BUT...BY MID TO LAKE
WEEK...THAT WILL REVERSE AND RETURN TO SEVERAL DEGREES WARMER THANNORMAL.
A COMPLEX STORM/FRONTAL SYSTEM WILL APPROACH FOR THE END OF THE
WEEK. LOW PRESSURE TRACK DIFFERS BETWEEN THE LONGER RANGE MODELS
AND THAT WILL AFFECT THE QPF. DOESN`T SEEM TO BE ENOUGH COLD AIR
IN THE CARDS TO GET EXCITED ABOUT THE PROSPECTS FOR BIG SNOW
HOWEVER.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
WINDS HAVE PICKED UP ACROSS THE CENTRAL AND WEST.
LLWS IN THE FCST.
06Z TAFS SENT.
SKIES HAVE CLEARED THOUGH THERE IS A CHANCE FOR LOWER CIGS AT
KBFD OVERNIGHT. CURRENTLY THERE IS A PERIOD OF VFR POSSIBLE LATE
EVENING. AS FLOW TURNS A BIT MORE WEST WITH A NW FETCH UPSTREAM.
CIGS WILL RE- ESTABLISH AT KBFD AND LIKELY FALL TO IFR BETWEEN 09Z
AND 12Z. THE SE WILL REMAIN VFR. W/SW SURFACE WINDS WILL RELAX A
BIT THIS EVENING...BUT COME BACK UP AGAIN LATER TONIGHT INTO SUN
WITH SURFACE SPEEDS OF 10-20KTS AND BREEZY IMPACTING MOST OF
CENTRAL PA AS A 35-50KT 850MB JET SLIDES OVERHEAD /BRINGING LLWS/.
TROUGH DROPPING THROUGH ON SUNDAY WILL BRING RETURN OF MVFR DECK
TO NW 2/3 OF CWA...WITH HIGHER TERRAIN KBFD-KJST SETTLING INTO
IFR. AS COLDER AIR PUSHES IN FROM THE NORTH...SNOW SHOWERS WILL
BECOME COMMON AT KJST-KBFD...AND HEADING INTO SUNDAY NIGHT AND
MONDAY AS UPPER TROUGH MOVES OVERHEAD - THERE WILL BE POTENTIAL
FOR SCT SNOW SQUALLS TO IMPACT THOSE AREAS AND WESTERN PA.
OUTLOOK...
SUN NIGHT-MON...REDUCTIONS ACROSS WESTERN HIGHER TERRAIN IN SNOW
SHOWERS AND POTENTIAL SCT SQUALLS. MAINLY CIG REDUCTIONS CENTRAL
MTNS. MAINLY VFR SE. BREEZY.
TUE-THU...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...CERU/MARTIN/RXR
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1123 PM CST SAT JAN 2 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...PRIMARILY IFR CONDITIONS AND MODERATE NORTHWEST WINDS
THROUGH THE NIGHT. HRRR MODEL AND SHORT TERM MODEL GUIDANCE MAINTAIN
HIGH POPS THROUGH DAWN AS A MID LEVEL TROUGH AXIS EVIDENT ON SAT
IMAGERY COMPLETES ITS TRANSIT OF TEXAS AND MOVES INTO THE NORTHWEST
GULF. HIGH PRESSURE WILL SPREAD OVER THE AREA OVERNIGHT AND EARLY
SUNDAY. AS RIDGING ALOFT TAKES OVER...LOOK FOR AN END TO RAIN SUNDAY
MORNING AND DRIER CONDITIONS. CEILINGS WILL LIFT TO MVFR AFTER DAWN
AND THEN TO VFR IN THE AFTERNOON. WINDS WILL DECREASE TO LIGHT TO
MODERATE FROM THE NORTH NORTHWEST.
&&
.PREV DISCUSSION... /ISSUED 527 PM CST SAT JAN 2 2016/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...ROUGHLY ANOTHER 12 HOURS OF PRIMARILY IFR CONDITIONS
AND MODERATE NORTHWEST WINDS. A MID LEVEL TROUGH AXIS WILL MOVE
OVERHEAD FROM WEST TO EAST AND HIGH PRESSURE WILL SPREAD OVER THE
AREA OVERNIGHT AND EARLY SUNDAY. AS RIDGING ALOFT TAKES OVER...
LOOK FOR AN END TO RAIN AND DRIER CONDITIONS. CEILINGS WILL LIFT
TO MVFR AFTER DAWN AND THEN TO VFR IN THE AFTERNOON. WINDS WILL
DECREASE TO LIGHT TO MODERATE FROM THE NORTH NORTHWEST.
PREV DISCUSSION... /ISSUED 256 PM CST SAT JAN 2 2016/
SHORT TERM /NOW THROUGH SUNDAY NIGHT/...RAINY OVERRUNNING PATTERN
WILL COME TO AN END TONIGHT/EARLY SUNDAY AS AN UPPER TROUGH MOVES
EAST ACROSS SOUTH TEXAS AND THE COASTAL TROUGH THAT HAS PERSISTED
OVER THE NORTHWEST GULF FOR DAYS PUSHES EAST AS WELL. CURRENT
FORECASTS LOOK VERY GOOD WITH LIKELY/CATEGORICAL CHANCES OF RAIN
FROM WEST TO EAST EARLY TONIGHT...THEN ONLY SLIGHT CHANCES OF RAIN
HANGING ON OVER THE SOUTHEAST PORTION OF THE FORECAST AREA SUNDAY
MORNING. RAIN CHANCES SHOULD CLEAR THE ENTIRE RIO GRANDE VALLEY BY
NOON ON SUNDAY. DESPITE ENDING RAIN CHANCES...AM NOT ANTICIPATING
THAT WE WILL SEE MANY BREAKS IN THE CLOUDS SUNDAY AFTERNOON.
CLEARING LOOKS TO OCCUR FROM WEST TO EAST SUNDAY NIGHT...MAINLY OVER
THE UPPER/MID RIO GRANDE VALLEY WITH CLOUDS HANGING ON MORE
STUBBORNLY ACROSS THE LOWER VALLEY SUNDAY NIGHT INTO EARLY MONDAY
MORNING. TONIGHT SHOULD BE THE COLDEST NIGHT WITH LOWS IN THE UPPER
30S/LOWER 40S ACROSS THE UPPER/MID RIO GRANDE VALLEY WITH LOWER/MID
40S CLOSER TO THE COAST. TEMPERATURE RECOVERY BEGINS ON SUNDAY WITH
HIGHS REACHING INTO THE MID/UPPER 50S MOST LOCALES.
LONG TERM /MONDAY THROUGH SATURDAY/...MODELS REMAIN IN GOOD
CONSISTENCY WITH THE GENERAL SOUTHWEST FLOW AND WITH THE SHORTWAVE
RIDGE AND TROUGHS THAT WILL MOVE WITH A PROGRESSIVE QUICK MID TO
UPPER LEVEL FLOW. ANOTHER SHOT OF RAIN IS EXPECTED MID WEEK ALONG
WITH A SLOW WARMING TREND THROUGH ALL OF NEXT WEEK WITH THE NEXT
COLD FRONT PROJECTED FOR SOMETIME NEXT SATURDAY.
SHORTWAVE RIDGE TO TRAVERSE THE STATE MONDAY WITH A BRIEF
REPRIEVE OF THE RAIN. THIS RIDGE IS THEN FOLLOWED BY A SERIES OF
SHORTWAVE TROUGHS WHICH WILL ONCE AGAIN ALLOW FOR COASTAL TROUGH
TO FORM TUESDAY. WILL CONTINUE TO TREND WITH THE ECMWF ON POP
TIMING WITH THE ONSET OF BEST CHANCE FOR RAIN TUESDAY AFTERNOON AS
THE ISENTROPIC UPGLIDE STRENGTHENS MAINTAINING A CHANCE OF RAIN
THROUGH WEDNESDAY THEN ENDING THE RAIN QUICKLY WEDNESDAY NIGHT AS
THE COASTAL TROUGH OR WEAK COASTAL LOW MOVES NORTHEAST AND WEAK
SUBSIDENCE AND DRYING TAKES PLACE THURSDAY. TEMPERATURES WILL
LIKELY BE A MORE TRICKY PROPOSITION WITH BOTH GFS/EC SHOWING
WARMING THROUGHOUT THE TUESDAY-WEDNESDAY RAIN TIME. GFS SEEMS MORE
IN LINE WITH A COOLER BIAS OF 5 TO 10 DEGREES AND SEEMS REASONABLE
WITH THICKENING CLOUDS AND AREAS OF RAIN REDUCING ANY HEATING. THE
EC IS LIKELY HOLDING ON TO THE IDEA THAT THE SURFACE TROUGH MOVES
INLAND ALLOWING FOR A BRIEF PERIOD OF EAST-SOUTHEAST WINDS THAT
COULD OFFER WARM AIR ADVECTION.
IMPROVING CONDITIONS ARE EXPECTED THURSDAY WITH A MUCH MORE
PLEASANT WEATHER PATTERN THROUGH THE END OF THE WORK WITH DRIER
AIR SETTLING OVER THE REGION. THERE REMAINS A SUBTLE TEMPERATURE
SPREAD BETWEEN GFS/EC WITH FORECAST BLEND STILL LEANING WITH A
SLIGHTLY COOLER BIAS BELOW BOTH THE GFS AND EC AND TRENDS CLOSER
TO WEATHER PREDICTION CENTERS FORECAST. NEXT FRONT IS ADVERTISED
BY BOTH MODELS TO MOVE THROUGH SOUTH TEXAS NEXT SATURDAY. ADDED IN
A SLIGHT CHANCE OF A SHOWER FOR GOOD MEASURE BUT CHANCES LOOK SLIM
AT THIS TIME. DO NOT SEE A LOT OF COLD AIR WITH THIS FRONT HOWEVER
MODELS ARE ADVERTISING A SHARP RIDGE BUILDING INTO PACIFIC
NORTHWEST AND BRITISH COLUMBIA WHICH MIGHT EVENTUALLY ALLOW FOR
SOME COLD AIR TO SPILL SOUTHWARD.
MARINE...NOW THROUGH SUNDAY NIGHT...BUOY020 CONTINUES TO SHOW NORTH
WINDS 19G23KT WITH SWELLS AROUND 7 FT THIS AFTERNOON WHILE SURFACE
OBS NEAR THE LAGUNA MADRE SHOW NORTH WINDS 15G20KTS. WINDS WILL
GRADUALLY WEAKEN TONIGHT AS THE SURFACE COASTAL TROUGHING ERODES
AWAY. THIS WILL ALLOW THE MARINE CONDITIONS TO GRADUALLY IMPROVE.
HOWEVER ELEVATED SWELLS WILL HOLD ON LONG ENOUGH IN THE GULF TO
REQUIRE AN SCA INTO AT LEAST PART OF THE OVERNIGHT HOURS AND HAVE
HELD ON TO THE 09Z SUN EXPIRATION TIME THAT IS CURRENTLY SET. SCEC
CONDITIONS MAY LINGER IN THE GULF THROUGHOUT THE DAY SUN.
MONDAY THROUGH THURSDAY...A MORE MODERATE WIND AND SEA REGIME TO
TAKE HOLD OF THE LOWER TEXAS COASTAL WATERS AS HIGH PRESSURE
TEMPORARILY BUILDS OVER THE WESTERN GULF. ANOTHER COASTAL TROUGH
DEVELOPS TUESDAY AS THE RIDGE PUSHES OFF TO EAST AS A SERIES OF
QUICK MOVING DISTURBANCES MOVE IN FROM THE WEST. THE TROUGH
STRENGTHENS WEDNESDAY AND MOVES TO THE EAST THURSDAY POSSIBLY AS A
STRENGTHENING LOW PRESSURE AREA. THE CLOSE PROXIMITY OF THE
TROUGH TO PROVIDE A BRIEF PERIOD OF MODERATE SOUTHEAST WINDS
FOLLOWED BY NORTHWEST WINDS THURSDAY. UNCERTAINTY ON HOW STRONG
THE TROUGH OR LOW MAY BECOME AND LATER FORECAST MAY INDICATE A
BRIEF PERIOD OF SMALL CRAFT ADVISORIES MID TO LATE NEXT WEEK.
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 3 AM CST SUNDAY FOR GMZ150-155-170-
175.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
935 PM CST MON JAN 4 2016
.UPDATE...
.AVIATION/06Z TAFS/...VFR CONDITIONS ARE FORECAST FOR TUE AND TUE
NT. MO CLEAR TO PARTLY CLOUDY SKIES ARE EXPECTED WITH ANY CLOUDS
PRESENT BEING CIRRUS. BREEZY SSWLY WINDS WILL DEVELOP BY LATE
MORNING ON TUE AND LAST THROUGH THE AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 321 PM CST MON JAN 4 2016/
SHORT TERM...
TONIGHT AND TUESDAY...FORECAST CONFIDENCE IS MEDIUM.
AREA OF VERY LIGHT LAKE EFFECT SNOW SHOWERS AND FLURRIES CONTINUE TO
MOVE SOUTHWESTWARD ACROSS THE FAR EASTERN COUNTIES. AS DELTA T
VALUES CONTINUE TO BECOME LESS FAVORABLE TOWARD EARLY
EVENING...THINK THAT THIS ACTIVITY WILL GRADUALLY WIND
DOWN. NOT EXPECTING ANY ADDITIONAL ACCUMULATIONS.
LAKE EFFECT CLOUDS SHOULD CONTINUE TO AFFECT THE EASTERN PORTIONS OF
THE AREA THIS EVENING...BEFORE LOW LEVEL WINDS WEAKEN AND SHIFT TO
THE SOUTH TO SOUTHWEST LATER TONIGHT. THESE CLOUDS SHOULD THEN
DISSIPATE OR PUSH BACK TO THE NORTHEAST LATER TONIGHT.
THERE IS UNCERTAINTY WITH HOW THE LOW STRATUS DECK OVER SOUTHERN
MINNESOTA INTO CENTRAL AND WESTERN IOWA WILL MOVE TONIGHT INTO
TUESDAY. 950 MB RAP HAS A DECENT HANDLE ON THIS CURRENT AREA...AND
SHIFTS IT SLOWLY NORTHEASTWARD TONIGHT INTO TUESDAY. IT DOES BRUSH
OUR FAR WESTERN COUNTIES TUESDAY MORNING. NOT SURE IF THIS DECK WILL
PUSH THAT FAR EAST...BUT WILL RAISE SKY COVER IN THE FAR WEST LATER
TONIGHT AND SPREAD IT EASTWARD INTO TUESDAY TO ACCOUNT FOR THIS
POSSIBILITY.
AS THE HIGH PUSHES EASTWARD TONIGHT INTO TUESDAY...WINDS WILL
GRADUALLY PICK UP OUT OF THE SOUTH TO SOUTHWEST...BECOMING GUSTY ON
TUESDAY. TEMPERATURES WILL DEPEND ON HOW MUCH CLOUD COVER REMAINS
OVER THE AREA...SO SOME UNCERTAINTY HERE AS WELL. FOR NOW...WENT
WITH MID TO UPPER TEENS TONIGHT...AND UPPER 20S TO AROUND 30 ON
TUESDAY.
TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE HIGH
THE UPPER FLOW BECOMES MORE SOUTHWEST WITH A VERY WEAK SHORTWAVE
APPROACHING SOUTHERN WISCONSIN WEDNESDAY THAT WEAKENS MORE AS IT
MOVES INTO THE AREA WEDNESDAY AFTERNOON. WEAK 700 MB UPWARD
MOTION CONTINUES. 700 MB RH SATURATES OVER SOUTH CENTRAL WISCONSIN
LATER IN THE AFTERNOON WITH FORECAST SOUNDINGS SHOWING THE
SATURATION ABOVE TO NEAR 300 MB. MOST OF THE MODELS ARE DRY WITH
AROUND A HUNDREDTH OF AN INCH OF PRECIPITATION JUST NORTHWEST OF
THE FORECAST AREA THROUGH THE AFTERNOON.
WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE HIGH
A WEAK SOUTHWEST UPPER FLOW PERSISTS BEHIND THE EXITING VERY WEAK
SHORTWAVE WHILE THE MAIN SHORTWAVE TROUGH MOVES INTO THE CENTRAL
PLAINS WITH THE WEAK RIDGE AHEAD OF THE TROUGH MOVING INTO
SOUTHWEST WISCONSIN LATE.
THE SOUTH LOW LEVEL FLOW MOISTENS AND SATURATES THE LOWER LEVELS
AND LIGHT PRECIPITATION AFFECTS SOUTHERN WISCONSIN. THE GFS
FORECAST SOUNDINGS INDICATE MAINLY SNOW INITIALLY...ESPECIALLY
NORTH AREAS WITH SOME FREEZING RAIN POTENTIAL BECOMING MAINLY
LIGHT RAIN LATER THURSDAY.
LONG TERM...
THURSDAY NIGHT AND FRIDAY...FORECAST CONFIDENCE IS MEDIUM.
THE SHORTWAVE PUSHES INTO THE MID MISSISSIPPI VALLEY FRIDAY
MORNING WHICH IS A LITTLE FASTER AND WEAKER ON THE 00Z ECMWF.
LOW PRESSURE EXITS THE KANSAS/OKLAHOMA REGION FRIDAY MORNING WITH
A RATHER WEAK BROAD LOW ACROSS NORTHERN ILLINOIS TO SOUTHERN
WISCONSIN BY FRIDAY EVENING.
ON THE GFS THE PRECIPITATION TRENDS TOWARD MAINLY RAIN.
FRIDAY NIGHT AND SATURDAY...FORECAST CONFIDENCE IS MEDIUM.
THE SHORTWAVE REACHES THE GREAT LAKES REGION FRIDAY NIGHT WITH A
SECOND SHORTWAVE SATURDAY ON THE ECMWF.
SURFACE LOW PRESSURE REACHES THE UPPER GREAT LAKES SATURDAY...WITH
THE 00Z ECMWF TRACK A LITTLE MORE WEST NEAR EASTERN LAKE SUPERIOR.
ON THE GFS THE PRECIPITATION TRENDS TURNS BACK TO MAINLY LIGHT SNOW
BY SATURDAY AS THE MID AND LOWER LEVELS COOL.
SUNDAY AND MONDAY...FORECAST CONFIDENCE IS MEDIUM.
A COLD MID/UPPER TROUGH DROPS DOWN FROM THE NORTHWEST SUNDAY AND
IS OVER THE UPPER MISSISSIPPI VALLEY AND WESTERN GREAT LAKES
MONDAY.
WHILE THE MODELS ARE MAINLY DRY...SOME VERY LIGHT SNOW OR FLURRIES
MAY OCCUR IN THE COLD NORTHWEST LOW LEVEL FLOW WITH A STRONG
RIDGE OF HIGH PRESSURE OVER THE NORTHERN PLAINS.
AVIATION/00Z TAFS/...
VERY LIGHT LAKE EFFECT SNOW SHOWERS AND FLURRIES SHOULD AFFECT
MILWAUKEE AND KENOSHA AT TIMES UNTIL AROUND 00Z TUESDAY. NO
ADDITIONAL ACCUMULATIONS ARE EXPECTED. CEILINGS MAY ALTERNATE
BETWEEN 2500 AND 3500 FEET ABOVE GROUND LEVEL. THESE CEILINGS
SHOULD LINGER INTO THE LATE EVENING AT THE EASTERN SITES...BEFORE
MOVING OFF TO THE NORTHEAST OR DISSIPATING.
OTHERWISE...HIGH PRESSURE OVER THE REGION WILL SLIDE TO THE EAST
TONIGHT AND TUESDAY. MOSTLY CLEAR SKIES ARE EXPECTED AT MADISON
INTO THIS EVENING. THERE IS UNCERTAINTY ON HOW FAR EAST THE LOW
STRATUS DECK OVER IOWA INTO SOUTHERN MINNESOTA WILL REACH LATER
TONIGHT INTO TUESDAY. KEPT THESE LOW CLOUDS OUT OF TAFS FOR NOW DUE
TO THE UNCERTAINTY.
NORTHEAST WINDS SHOULD GRADUALLY WEAKEN AND BECOME LIGHT
TONIGHT...BEFORE BECOMING GUSTY OUT OF THE SOUTH TO SOUTHWEST ON
TUESDAY.
MARINE...
CANCELLED THE CURRENT SMALL CRAFT ADVISORY ACROSS THE
NEARSHORE WATERS OF LAKE MICHIGAN...AS WINDS AND WAVES HAVE
FALLEN BELOW CRITERIA.
ISSUED ANOTHER SMALL CRAFT ADVISORY FROM 12Z TUESDAY UNTIL 15Z
WEDNESDAY...AS GUSTY SOUTH TO SOUTHWEST WINDS AND BUILDING WAVES ARE
EXPECTED WITH A TIGHT PRESSURE GRADIENT DEVELOPING. ANY HIGH WAVES
WOULD BE TOWARD OR OVER THE OPEN WATERS DURING THIS TIME.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 6 AM TUESDAY TO 9 AM CST WEDNESDAY FOR
LMZ643>646.
&&
$$
UPDATE...GEHRING
TONIGHT/TUESDAY AND AVIATION/MARINE...WOOD
TUESDAY NIGHT THROUGH MONDAY...HENTZ
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
920 PM MST MON JAN 4 2016
.UPDATE...UPDATED AVIATION DISCUSSION.
&&
.SYNOPSIS...
SEVERAL STORM SYSTEMS WILL MOVE THROUGH THE AREA THIS WEEK...BRINGING
COOLER AFTERNOON HIGHS...MILD NIGHTS...CLOUDY SKIES...AND AN ELEVATED
CHANCE OF RAINFALL THROUGH THE END OF THE WEEK. CONDITIONS WILL
START TO DRY OUT FOR THE COMING WEEKEND...BUT TEMPERATURES WILL
REMAIN BELOW SEASONAL NORMALS.
&&
.DISCUSSION...
MAIN MID-TROPOSPHERIC TROUGH AXIS CONTINUES TO PIVOT CYCLONICALLY
INTO NORTHERN AND EASTERN AZ. FROM A QUASI-GEOSTROPHIC
PERSPECTIVE...FORCING FOR ASCENT HAS BEEN WANING. HOWEVER...WEAK
ISENTROPIC MOISTURE TRANSPORT HAS BEEN SUFFICIENT TO SUPPORT A SOLID
LINE OF LIGHT TO MODERATE RAIN ACROSS SOUTH-CENTRAL AZ. LATEST RUNS
OF THE HRRR INDICATE THE LINE WILL CONTINUE TO DISSIPATE AS IT SLIDES
EASTWARD THIS EVENING. SOME LOCATIONS HAVE PICKED UP AS MUCH AS A
HALF OF AN INCH OF RAIN IN THIS LINE AND ANOTHER TENTH OF AN INCH IS
POSSIBLE...MAINLY ACROSS PORTIONS OF THE EAST VALLEY. GENERAL
CONSENSUS AMONGST THE HI-RES GUIDANCE IS THAT THE ACTIVITY WILL THEN
BECOME MORE ISOLATED THROUGH MIDNIGHT...BEFORE SHIFTING INTO THE
FAVORED AREAS OF THE HIGHER TERRAIN NORTH AND EAST OF PHOENIX. MINOR
ADJUSTMENTS WERE MADE TO THE SHORT-TERM TEMPERATURES...DEWPOINTS AND
WINDS. OTHERWISE...THE FORECAST REMAINS ON TRACK.
&&
.PREVIOUS DISCUSSION...
LOOKING AT A MIXED CONFIDENCE FORECAST OVER THE NEXT FEW DAYS AS A
SERIES OF TROUGHS WILL MOVE THROUGH AND IMPACT THE AREA. THERE IS
VERY HIGH CONFIDENCE THAT ALL LOCATIONS WILL SEE MEASURABLE
PRECIPITATION AT SOME POINT /IF NOT SEVERAL TIMES OVER/ BY THE END OF
THE WEEK. THE UNCERTAINTY RESIDES IN EXACTLY WHEN THE RAIN WILL
OCCUR. RAINFALL LOOKS TO TAPER OFF THIS EVENING AND OVERNIGHT AS THE
INITIAL TROUGH AND RESULTING SUBSIDENCE BEGINS TO DOMINATE OVER THE
REGION. BY SOME INDICATIONS...TUESDAY MORNING SHOULD START OFF
RELATIVELY DRY. HOWEVER...MOIST ADVECTION /MODEST IVT SIGNAL FROM GFS
AND GEFS/ AND WEAK ISENTROPIC FORCING WILL BEGIN DURING THE DAY IN
ADVANCE OF A SECOND TROUGH...WITH RAINFALL POSSIBLE AGAIN TUESDAY
AFTERNOON AND EVENING. SREF PRECIP PLUMES ARE ADMITTEDLY ALL OVER THE
MAP UNTIL 06Z WEDNESDAY...AT WHICH POINT NEARLY ALL 26 MEMBERS
SUGGEST MEASURABLE PRECIP ACROSS THE DESERTS. DECIDING EXACTLY WHEN
THE RAIN WILL START IS A CHALLENGE...BUT POPS HAVE BEEN ADJUSTED TO
HIGHLIGHT THE LATE TUESDAY/EARLY WEDNESDAY TIME PERIOD AS ANOTHER
OPPORTUNITY FOR RAINFALL. THIS SECONDARY TROUGH SHOULD RAPIDLY MOVE
THROUGH THE AREA WEDNESDAY MORNING AND THE OPERATIONAL RUNS OF THE
ECMWF...NAM...AND GFS ARE EVEN TRYING TO SUGGEST SOME BREAKS IN THE
CLOUDS WEDNESDAY AFTERNOON.
TROUGH NUMBER 3 APPEARS POISED TO ARRIVE LATE WEDNESDAY NIGHT/EARLY
THURSDAY MORNING WITH ANOTHER NARROW BAND OF ENHANCED IVT AND
ISENTROPIC FORCING. ONCE AGAIN IT APPEARS THAT ELEVATED POPS ARE
WARRANTED AT THIS POINT AND THEY WERE NUDGED TOWARD THE LATEST RUN OF
THE NAEFS. FOLLOWING A BRIEF BREAK...THE FOURTH AND POSSIBLY FINAL
TROUGH LOOKS TO BE QUEUED UP FRIDAY MORNING WITH DRYING AND WEAK
UPPER RIDGING BEGINNING TO TAKE HOLD EARLY SATURDAY MORNING. QUITE A
BUSY WEEK TO SAY THE LEAST.
IN TERMS OF PRECIP AMOUNTS FOR THE WEEK AS A WHOLE...A HEALTHY BLEND
OF 50TH PERCENTILE QPF FROM ALL AVAILABLE GUIDANCE WEIGHTED TOWARD
WPC VALUES YIELDS ABOUT 1.5 TO 1.75 INCHES OVER THE DESERTS...WITH
SOME TOTALS PUSHING 3 INCHES NORTH/EAST OF PHOENIX. IT WOULD APPEAR
AT NO TIME SHOULD WE BE LOOKING AT MORE THAN A QUARTER TO A HALF INCH
OVER A 6 HR PERIOD. WASHES WILL LIKELY BEGIN RUNNING IN SOME AREAS
THIS WEEK AND SOME LOW-LYING AREAS COULD SEE MINOR HYDRO ISSUES...BUT
WIDESPREAD FLOODING DOESN`T APPEAR LIKELY AT THIS POINT. SHOULD THE
FORECAST VERIFY AS ADVERTISED...THIS SHOULD BE A STRATIFORM/BENEFICIAL
RAIN FOR THE AREA VS. A MAJOR HYDRO OR FLOODING EVENT. COLDER AIR
WILL EVENTUALLY WORK ITS WAY INTO THE AREA LATE IN THE WEEK RESULTING
IN SOME MIXED PRECIPITATION ACROSS THE HIGHEST MOUNTAIN PEAKS
NORTH/EAST OF PHOENIX. AT THIS POINT IT APPEARS ANY NOTEWORTHY
ACCUMULATIONS WILL BE CONFINED TO THE VERY HIGHEST PEAKS AND LOWEST
IMPACT AREAS ABOVE 6000 FT.
NORTHWEST FLOW AND WEAK DRY ADVECTION ACROSS THE AREA LOOKS LIKELY
THROUGH THE WEEKEND INTO NEXT WEEK...ALTHOUGH THERE`S SOME HINT AT A
DRY TROUGH MOVING THROUGH THE AREA ON SUNDAY /SOME INCREASED CLOUD
COVER AND THAT`S ABOUT IT/. SHOULD THIS TROUGH NOT DEVELOP...WE`LL NEED
TO KEEP AN EYE ON FOG POTENTIAL THIS WEEKEND /SATURDAY OR SUNDAY/ IF
THE BL DOESN`T SUFFICIENTLY DRY OUT. THE PATTERN IS CERTAINLY
CONDUCIVE FOR WIDESPREAD FOG DEVELOPMENT ACROSS THE AREA AND IT
WARRANTS MENTIONING. FAIRLY GOOD AGREEMENT OF STRONG UPPER RIDGING
ACROSS THE AREA BY MONDAY OF NEXT WEEK WITH TEMPERATURES RETURNING TO
EARLY JANUARY NORMALS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SHOWERS WILL CONTINUE TO DISSIPATE IN INTENSITY AND COVERAGE ACROSS
THE PHOENIX METRO AREA THROUGH 06Z-08Z. THEREAFTER...THE BEST CHANCE
FOR PRECIPITATION WILL SHIFT INTO THE HIGHER TERRAIN NORTH AND EAST
OF THE VALLEY. CIGS WILL BE THE MAIN AVIATION WEATHER CONCERN OVER
THE NEXT 24 HOURS. PREPONDERANCE OF MODEL GUIDANCE CONTINUES TO
SUGGEST THAT CIGS WILL LOWER TO 4K FT LATER THIS MORNING AND PERSIST
THROUGH MUCH OF THE DAY TUESDAY. THERE IS ALSO A CHANCE THEY COULD
OCCASIONALLY LOWER TO AROUND 2500 FT AS SATURATION INCREASES BETWEEN
10Z AND 14Z.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NOT MUCH OF A THREAT FOR SHOWER ACTIVITY THROUGH 18Z WED...THOUGH THE
CHANCE FOR PRECIP WILL INCREASE TUESDAY AFTERNOON AND
EVENING...PARTICULARLY AT KIPL. UNTIL THEN...LOWER CIGS BETWEEN 2K
AFN 4K FT WILL PERSIST AT KBLH. SOMEWHAT BETTER CONDITIONS AT KIPL.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
SEVERAL WEATHER DISTURBANCES WILL MOVE THROUGH THE DISTRICTS IN CLOSE
SUCCESSION THIS WEEK WITH HIGHLY VARIABLE RAINFALL OCCURRING EACH
DAY THROUGH FRIDAY...MAINLY EAST OF THE LOWER COLORADO RIVER VALLEY.
RAIN CHANCES TAPER OFF FOR THE WEEKEND. HUMIDITY WILL BE MUCH ABOVE
AVERAGE WITH MINIMUM VALUES NEAR AND ABOVE 45 PERCENT MOST DAYS ON
THE LOWER DESERTS AND MAX VALUES NEAR AND ABOVE 80 PERCENT MUCH OF
THE TIME. VALUES TREND DOWN FROM WEST TO EAST SATURDAY INTO SUNDAY
BUT GENERALLY REMAIN ABOVE 30 PERCENT MOST PLACES. EXPECT WELL BELOW
NORMAL HIGH TEMPERATURES THROUGH FRIDAY WITH DESERT HIGHS IN THE
50S...AND SLIGHT WARMING OVER THE WEEKEND AS HUMIDITIES START TO
FALL OFF. DESPITE THE ACTIVE WEATHER PATTERN NO STRONG WIND EVENTS
ARE EXPECTED BUT JUST BREEZY AT TIMES...MAINLY WEDNESDAY AND
THURSDAY.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...LEINS
AVIATION...HIRSCH
FIRE WEATHER...AJ/CB
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1255 AM MST TUE JAN 5 2016
.UPDATE...
ISSUED AT 1251 AM MST TUE JAN 5 2016
WEBCAMS SHOW ACCUMULATING SNOW FOR OUR SOUTHERN VALLEYS THIS
MORNING AND AFTER SOME CALLS TO LOCAL LAW ENFORCEMENT...FELT IT
PRUDENT TO ISSUE ADVISORIES FOR SE UT AND ALL SRN CO VALLEYS.
RAP13 AND HRRR ALSO SHOW SNOW CONTINUING THROUGH THE MORNING HOURS
AND ARE HANDLING CURRENT SNOW WELL. SOME AREAS WILL SEE LITTLE
ACCUMULATION WHILE OTHERS WILL LIKELY SEE 1 TO 3 INCHES WITH
POSSIBLY HIGHER AMOUNTS AT HIGHER ELEVATIONS. WHILE THESE AMOUNTS
ARE SUB- ADVISORY CRITERIA...THE MORNING COMMUTE WILL BE A MESS
WITH SNOW AND ICY COVERED ROADS ANTICIPATED. THE ADVISORY LASTS
THROUGH 10AM THIS MORNING AND CAN BE PULLED DOWN EARLY IF
REQUIRED. UPPED SNOW AMTS AND POPS THROUGH THIS MORNING.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 352 PM MST MON JAN 4 2016
TEMPERATURES TODAY HAVE SKYROCKETED AS WARM AIR ADVECTS INTO THE
FOUR CORNERS REGION. THE MOUNTAIN AND VALLEY TEMPERATURES ARE MUCH
MORE ISOTHERMAL THIS AFTERNOON THAN THEY HAVE BEEN RECENTLY
THANKS TO MIXING OF THIS WARMER AIR INTO SOME OF THE LOWER
VALLEYS. THE NOTABLE EXCEPTIONS ARE VERNAL AND GUNNISON WHERE
THEIR MAX TEMPS ARE STILL LINGERING IN THE SINGLE DIGITS TO TEENS.
CURRENT SATELLITE AND RADAR IMAGERY COMBINED WITH OBS INDICATE
DEEPEST MOISTURE OVER CENTRAL ARIZONA HEADED THIS WAY. THE
LOWERING OF THE CLOUD DECK IS EVIDENT AT THE BLANDING ASOS...AND
THIS TREND WILL CONTINUE THROUGHOUT THE EVENING. THE BEST CHANCE
OF PRECIPITATION ACROSS SE UTAH AND SW COLORADO WILL BE BETWEEN
10PM AND EARLY TUESDAY MORNING AS A COUPLE OF H5 VORT LOBES HELP
TO ORGANIZE SHOWER ACTIVITY AS THEY STREAM NORTH INTO THE FOUR
CORNERS REGION. EXPECTING A FEW SHOWERS MAINLY ABOVE 7000 FEET
ELSEWHERE BUT MOST LOWER VALLEYS NORTH OF THE SAN JUANS WILL
REMAIN DRY. GENERALLY AN INCH OF SNOW IS EXPECTED ALONG THE
VALLEYS OF SE UTAH AND SW COLORADO WITH CLOSER TO 2 TO 4 INCHES
POSSIBLE ALONG THE SOUTH-FACING AREA OF THE SOUTHERN SAN JUANS AND
ABAJOS. THE PRECIPITATION WHICH FALLS ACROSS VALLEYS OF SE UTAH
TONIGHT BELOW 5500 FEET MAY BEGIN TO MELT AROUND THAT ELEVATION BEFORE
IT REACHES THE GROUND BUT IS EXPECTED TO REMAIN AS FROZEN
PRECIPITATION.
RELATIVELY MOIST AND MILD AIR MASS WILL BE OVERRIDING COLD SURFACE
TEMPERATURES ON TUESDAY MORNING AS PACIFIC SHORT WAVE LIFTS
NORTHEAST OVER THE WESTERN SLOPE ON TUESDAY. EXAMINING WET BULB
TEMPERATURES IN THE 1 KM LAYER ABOVE THE SURFACE SUGGEST THAT
PRECIPITATION TYPE MIGHT BE RAIN. IF RAIN DOES OCCUR...THEN SPOTTY
FREEZING RAIN IS A POSSIBILITY IN THE LOWER VALLEYS (BELOW 5000
FEET) GIVEN SUB FREEZING TEMPS ARE LIKELY. I THINK THIS IS AN
UNLIKELY SCENARIO AS MODEL DATA MAY NOT HAVE THE BEST HANDLE ON
SNOW COVERED SURFACE CONDITIONS...THE COLD BOUNDARY LAYER IS
LIKELY DEEPER THAN WHAT MODEL DATA SHOWS. HOWEVER IT IS WORTH
MENTIONING THIS OUTCOME SINCE FREEZING RAIN IS RARE...BUT LIGHT
SNOW IS THE LIKELY SCENARIO IF PRECIPITATION OCCURS IN THE LOWER
VALLEYS.
PRECIPITATION...MOSTLY SNOW...WILL BE FOCUSED OVER THE SOUTHERN
HALF AS THE SHORT WAVE WILL BE WEAKENING AS IT REACHES THE
NORTHERN AREAS. THIS TREND LASTS INTO TUES EVENING.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 352 PM MST MON JAN 4 2016
THERE WILL BE A LULL IN THE ACTIVITY TUES AFTERNOON/EVENING...BUT
THE NEXT STRONGER PACIFIC WAVE MOVES ACROSS THE REGION LATE
TUES NIGHT INTO WED EVENING. AIR MASS WILL BE MOIST WITH DECREASING
STABILITY GIVEN THE MID LEVEL COLD ADVECTION. SURPRISINGLY...THE
IN HOUSE LIGHTNING POTENTIAL SHOWS POCKETS OF INSTABILITY PER NAM
MODEL...AND THE DAY 3 CONVECTIVE OUTLOOK SHOWS THUNDER POTENTIAL
FOR THE LOWER ELEVATIONS OF THE FORECAST AREA. TYPICALLY THUNDER
DOES NOT OCCUR WHEN THE DESERT VALLEYS HAVE SNOW ON THE GROUND.
HOWEVER ITS NOT UNUSUAL FOR MOIST PACIFIC WAVES TO TRIGGER STORMS
ASSOCIATED WITH THE TROUGH AXIS PASSAGE. REGARDING WINTER
WEATHER...MODERATE SNOW ACCUMULATIONS ARE LIKELY OVER THE SAN JUAN
MOUNTAINS AND WINTER WEATHER ADVISORIES MAY BE NECESSARY FOR
SOUTHWEST COLORADO...POSSIBLY EXTENDING AS FAR NORTH AS THE GRAND
MESA.
THE FORECAST CONFIDENCE DIMINISHES DURING THE LATTER PART OF THE
WEEK. THE MEDIUM RANGE MODELS ARE SHOWING A LACK OF CLARITY
REGARDING HOW MUCH POLAR INFLUENCE REACHES THE INTERIOR WEST AND
THE CENTRAL ROCKIES. BROAD TROUGH WILL BE POSITIONED OVER THE
CENTRAL CONUS...BUT SOME PACIFIC MOISTURE MAY BE ENTRAINED INTO
THE NORTHWEST FLOW. THE 12Z MODEL GUIDANCE DOWNPLAYED THIS
POTENTIAL. CONSENSUS POPS SHOW 20-30 PERCENT POPS FOR THE WESTERN
SLOPES MOUNTAINS FROM FRIDAY THROUGH SUNDAY TIME FRAME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 957 PM MST MON JAN 4 2016
LIGHT SNOW HAS DEVELOPED OVER THE SOUTHERN VALLEYS AND HILLS OF
UTAH AND SOUTHWEST COLORADO THIS EVENING. PROBABILITIES ARE HIGH
THAT KDRO WILL BE IMPACTED BY IFR CONDITIONS FOR AN EXTENDED
PERIOD OVERNIGHT INTO TUESDAY MORNING. KTEX WILL BE ALSO BE
IMPACTED BY LOW MVFR CIGS THROUGH 10Z THEN SNOW COULD SETTLE IN
AND BRING IFR CONDITIONS THROUGH THE MORNING HOURS. KCNY AND KVEL
COULD BE IMPACTED FROM SOME LIGHT FOG AND BRING MVFR CONDITIONS
BUT PROBABILITIES AND CONFIDENCE LOW. THE REMAINING TERMINAL
FORECAST SITES ARE EXPECTED TO HAVE VFR CONDITIONS PREVAIL THOUGH
ILS BREAK POINTS MAY BE EXCEEDED AS CIGS LOWER THROUGH SUNRISE.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL 10 AM MST THIS MORNING FOR
COZ021>023.
UT...WINTER WEATHER ADVISORY UNTIL 10 AM MST THIS MORNING FOR UTZ022-
028.
&&
$$
UPDATE...TGR
SHORT TERM...JAM/PF
LONG TERM...PF
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS NEW YORK NY
112 AM EST TUE JAN 5 2016
.SYNOPSIS...
CANADIAN HIGH PRESSURE BUILDS OVER THE AREA THROUGH TUESDAY...THEN
BUILDS TO THE SOUTH TUESDAY NIGHT THROUGH THURSDAY. ANOTHER AREA
OF HIGH PRESSURE BUILDS TO THE NORTH THURSDAY NIGHT AND
FRIDAY...RETREATING TO THE CANADIAN MARITIMES FRIDAY NIGHT AND
SATURDAY. AN UNSETTLED WEATHER PATTERN LOOKS IN STORE FOR THE AREA
OVER THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
700-300 HPA TROUGH AXIS SWINGS THROUGH INTO THE EARLY MORNING
HOURS...THEN DEEP LAYERED RIDGING BEGINS TO BUILD IN TOWARDS
MORNING. ANY LINGERING STRATO-CUMULUS SHOULD DISSIPATE AS THE
TROUGH AXIS SLIDES TO THE EAST/RIDGING BEGINS TO BUILD IN. STILL
ON TRACK FOR CLEAR SKY CONDITIONS OVERNIGHT.
COLD AIR ADVECTION AND A TIGHT PRESSURE GRADIENT WILL RESULT IN A
CONTINUATION OF GUSTY WINDS AND PLUMMETING TEMPS. AFTER RECORD
WARMTH FOR NOVEMBER AND DECEMBER...THE COLDEST NIGHT OF THE SEASON
IS ANTICIPATED. WITH COLD BEING LIMITED BY STRENGTH OF WIND TO
WHAT COLD ADVECTION BRINGS IN. NOTING ALREADY TEMPERATURES UNDER
CUTTING FORECAST BY 2-4 DEGREES AT MANY LOCATIONS. HAVE UPDATED
USING A BLEND OF THE LOWEST VALUE OF LAV/MAV/MET GUIDANCE AND NAM
AND HRRR 2-METER TEMPERATURES AND THOSE INDIVIDUAL CONSTITUENTS.
THE BLEND WAS WEIGHED TOWARDS THE COLDEST VALUE AT ANY GIVEN
POINT. LOWS GENERALLY 10-15 NEAR THE COAST...EXCEPT UPPER TEENS
EASTERN TWIN FORKS OF LONG ISLAND...AND SINGLE DIGITS ELSEWHERE.
ALSO...WINDS RUNNING A TAD STRONGER THAN PREVIOUSLY FORECAST...SO
IMPACT OF GUSTY NORTH WINDS WITH A SLIGHTLY COLDER TEMPERATURE
FORECASTS...WILL PRODUCE WIND CHILLS SLIGHTLY COLDER THAN
PREVIOUSLY FORECAST AT MOST LOCATIONS. WIND CHILL VALUES
OVERNIGHT WILL RUN AROUND ZERO TO 5 BELOW ACROSS NYC/LONG ISLAND
AND 5 TO 10 BELOW ELSEWHERE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
RIDGE BUILDS THIS TIME FRAME BEHIND THE DEPARTING TROUGH.
SUBSIDENCE WILL ENSURE CLEAR SKIES THROUGH WED.
AS THE CENTER OF HIGH PRESSURE NEARS...ANY RESIDUAL GUSTS
WILL DIMINISH TUESDAY...AND WINDS REMAIN LIGHT OR CALM TUESDAY NIGHT.
A VERY COLD START TO THE DAY IS EXPECTED...AND TEMPS REMAIN QUITE
CHILLY TUESDAY...REMAINING BELOW FREEZING FOR THE MOST PART ACROSS
THE CWA.
AT NIGHT...TEMP FORECAST IS A BIT MORE CHALLENGING. WARM AIR
ADVECTION WILL BE UNDERWAY...BUT CLEAR SKIES AND LIGHT WINDS WILL
PROMOTE RADIATIONAL COOLING. THERE IS A TEMP DISPARITY IN THE MOS
GUIDANCE...AND AMONG ENSEMBLE GUIDANCE. WILL NOT STRAY TOO FAR
FROM PREVIOUS FORECAST...TAKING A BLEND OF AVAILABLE GUIDANCE BUT
SIDING ON THE LOWER END OF THE SPREAD.
TEMPS MODIFY ON WEDNESDAY AS THE CENTER OF THE HIGH PASSES TO THE
SOUTH AND RETURN FLOW W/SW WINDS PREVAIL.
TEMPS LIKELY RISE CLOSE TO IF NOT JUST ABOVE SEASONAL NORMS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
THE H5 FLOW IS IN GOOD AGREEMENT THROUGH FRI...BUT THEN DIFFERENCES
BEGIN TO TAKE SHAPE FROM THE INTERACTION BETWEEN A LARGE CANADIAN
VORTEX OVER HUDSON BAY AND A CUTOFF LOW PRES SYSTEM MOVING ONSHORE
OUT WEST. THE 12Z MODELS SEEM TO BE IN SOMEWHAT BETTER AGREEMENT
THAN THE 00Z RUNS WITH THE OVERALL PATTERN...THAT BEING THE
ELONGATED E-W ORIENTED VORTEX BECOMING N-S ORIENTED WITH A COLDER
AIRMASS DIVING INTO THE NORTHERN PLAINS/UPPER MIDWEST/GREAT LAKES
FOR THE WEEKEND. THIS VORTEX WILL THEN MEANDER ABOUT ERN ONTARIO
THROUGH THE MIDDLE OF NEXT WEEK.
IN TERMS OF SENSIBLE WEATHER...DRY AND NEAR TO SLIGHTLY ABOVE NORMAL
TEMPERATURES THROUGH FRI WITH HIGH PRES IN CONTROL. WARM AIR
ADVECTION RAINS MOVE INTO THE AREA FRI NIGHT THROUGH
SAT...ALTHOUGH THE RETREATING HIGH TO THE NORTH WILL RESULT IN
COLD AIR DAMMING WITH A POSSIBILITY OF A WINTRY MIX OF
PRECIPITATION ACROSS THE INTERIOR TO START. SHOULD TURN TO PLAIN
RAIN AT ALL LOCATIONS BY SAT AFTERNOON. THE AMOUNT OF QPF REMAINS
IN QUESTIONS AS THERE IS THE POTENTIAL FOR A WAVE OF LOW PRES TO
DEVELOP OFF THE MID ATLANTIC COAST AND PASS SOUTH OF LONG ISLAND
ON SAT. HAVE KEPT LOW CHANCE POPS IN THE FORECAST SAT NIGHT INTO
SUN...ALTHOUGH WE MAY END UP SEEING A LULL IN PRECIPITATION BEFORE
THE NEXT POTENTIAL SYSTEM TRACKS UP FROM THE S. THIS SYSTEM
CURRENTLY LOOKS WARM ENOUGH FOR ALL RAIN...BUT IF THE UPPER
PATTERN CHANGES AND THE STORM SHIFTS A BIT FURTHER OFFSHORE...IT
P-TYPE COULD BE MIXED OR IN SOLID FORM. WEAK HIGH PRES RETURNS FOR
MONDAY.
TEMPS ARE EXPECTED TO BE ABOVE NORMAL LEVELS THROUGH THE REMAINDER
OF THE PERIOD.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE CENTERED OVER THE GREAT LAKES REGION BUILDS SLOWLY
OVER THE TERMINALS THROUGH 00Z WEDNESDAY...THEN REMAINS ALONG THE
MID ATLANTIC COAST INTO WEDNESDAY MORNING.
VFR THROUGH THE TAF PERIOD...WITH A SCATTERED TO BROKEN DECK 5 TO 6K
FT TIL 08Z TO 09Z...FROM THE NYC TERMINALS EAST. OTHERWISE
CLEAR.
NORTH WINDS SUSTAINED 15 TO 20 KT WITH GUSTS 25 TO 30 KT UNTIL
AROUND 10Z WITH SUSTAINED WINDS AND GUSTS SLOWLY DIMINISHING.
GUSTS ARE EXPECTED TO END 14Z TO 17Z. WINDS BACK TO NORTHWEST DURING
THE AFTERNOON...REMAINING MAINLY TO THE RIGHT OF 310 TRUE,,,THEN
BECOME MORE WESTERLY AFTER 02Z WEDNESDAY.
.OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...
.LATE TUESDAY NIGHT-FRIDAY...VFR.
.FRIDAY NIGHT...MVFR OR LOWER LIKELY...IN RAIN...WITH A WINTRY MIX
POSSIBLE AT KSWF. E WINDS G15-20KT POSSIBLE.
.SATURDAY...MVFR OR LESS LIKELY IN RAIN.
&&
.MARINE...
WIND GUSTS RUNNING HIGHER THAN EXPECTED. WITH LOW LEVEL WINDS
FORECAST TO INCREASE INTO THE OVERNIGHT HOURS...BEFORE DIMINISHING
TOWARDS SUNRISE...HAVE ISSUED A GALE WARNING FOR ALL WATERS
THROUGH 12Z.
THE WINDS WILL DECREASE ON TUESDAY AS THE PRESSURE GRADIENT
SLACKENS OVER THE REGION. WOULD EXPECT GUSTS TO 25-30 KT TO
CONTINUE OVER THE OCEAN WATERS/BAYS OF LONG ISLAND/EASTERN SOUND
INTO THE MORNING HOURS. SEAS SHOULD REMAIN ABOVE SCA LEVELS ON THE
COASTAL OCEAN WATERS INTO TUESDAY AFTERNOON...DEPENDING ON EXACTLY
HOW QUICKLY THE WINDS SUBSIDE.
TRANQUIL CONDITIONS ARE ANTICIPATED LATE TUESDAY THROUGH
WEDNESDAY.
SUB-ADVISORY CONDITIONS PREVAIL WED NIGHT THROUGH FRIDAY WITH A
WEAK PRES GRADIENT OVER THE AREA. WINDS AND SEAS WILL INCREASE FRI
NIGHT IN RESPONSE TO AN STRENGTHENING EASTERLY FLOW. WINDS SHOULD
SUBSIDE ON SAT...BUT SEAS ON THE OCEAN WILL LIKELY LINGER.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS FORECAST THROUGH FRIDAY. THE NEXT
CHANCE FOR RAIN IS FRIDAY NIGHT CONTINUING THROUGH SATURDAY.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...GALE WARNING UNTIL 7 AM EST THIS MORNING FOR ANZ330-335-338-
340-345-350-353-355.
&&
$$
SYNOPSIS...24/MALOIT/PW
NEAR TERM...MALOIT/PW/DW
SHORT TERM...PW
LONG TERM...24
AVIATION...MET/DW
MARINE...24/MALOIT/PW
HYDROLOGY...24/PW
AREA FORECAST DISCUSSION
NWS MIAMI FL
1251 AM EST TUE JAN 5 2016
.AVIATION...
VFR CONDITIONS ARE FORECAST TO PREVAIL THROUGH THE FORECAST PERIOD
EXCEPT FOR A SLIM CHC OF PERIODS OF MVFR CEILINGS MAINLY ALONG THE
SE FL COAST. BUT GIVEN CONFIDENCE ON THAT IS LOW IT IS NOT
CURRENTLY REFLECTED ON THE FORECAST AND WILL AMEND AS NEEDED IF
THIS BECOMES A CONCERN OR ADDRESS IN FUTURE UPDATES. SOMETHING
NOT PICKED UP BY SHORT TERM MOS GUIDANCE BUT PICKED UP BY HRRR AND
A COUPLE OF LOCAL MODEL RUNS IS A LAND BREEZE PARTICULARLY ALONG
SE COAST SITES FROM FLL NORTH THROUGH AROUND DAWN WHEN THE LOW
LEVEL NE FLOW KICKS IN. THIS IS IN LINE WITH CURRENT OBSERVATIONS
SO REFLECTED THE LAND BREEZE ON TAF FORECAST FOR SITES FROM FLL
NORTH ACCORDINGLY THROUGH THE FIRST 6 HOURS OF THE FORECAST EARLY
THIS MORNING. AFTER DAWN BLUSTERY NE WINDS WILL DEVELOP THROUGH
THE DAY AT ALL SITES AND CONTINUE INTO THE EVENING. SOME MOISTURE
WILL STREAM NORTH FROM THE SOUTH TODAY WARRANTING MENTION OF VCSH
PARTICULARLY ALONG SE FL SITES.
&&
.PREV DISCUSSION... /ISSUED 833 PM EST MON JAN 4 2016/
UPDATE...
HIGH PRESSURE IS SLOWLY BUILDING IN BEHIND THE COLD FRONT THAT
MOVED THROUGH. THE WIND IS BECOMING LIGHT TONIGHT, WHICH MAY ALLOW
SOME OF THE TEMPERATURES IN THE INTERIOR AREAS TO BE SOMEWHAT
CHILLIER THAN WHAT HAS BEEN FORECAST. HOWEVER, AS THE HIGH BUILDS
TO THE NORTH, THE WIND IS EXPECTED TO INCREASE OUT OF THE
NORTHEAST TONIGHT. THIS WOULD HELP TO CURTAIL ANY RADIATIONAL
COOLING TONIGHT. OVERALL, THE FORECAST LOW TEMPERATURES SHOULD BE
FAIRLY CLOSE, WITH ISOLATED POCKETS OF SOMEWHAT LOWER TEMPS. HAVE
MADE NO ADJUSTMENTS AT THIS TIME.
OTHERWISE, THE WEATHER SHOULD BE MOSTLY QUIET THROUGH THE
OVERNIGHT HOURS. MADE SOME TWEAKS TO THE FORECAST TO ACCOUNT FOR
CURRENT CONDITIONS.
PREV DISCUSSION... /ISSUED 650 PM EST MON JAN 4 2016/
AVIATION...
VFR CONDITIONS ARE FORECAST THROUGH THE TAF PERIOD AS CONDITIONS
SHOULD BE QUIET UNTIL THE MORNING HOURS. THE WIND WILL BE
GENERALLY NORTHERLY FOR THE FIRST PART OF THE NIGHT AS HIGH
PRESSURE BUILDS IN TO THE NORTH. AS IT CONTINUES TO BUILD TONIGHT,
THE WIND WILL TURN MORE NORTHEASTERLY. THIS MAY BRING SOME SHOWERS
TO THE SOUTHEAST FLORIDA COASTAL AREAS BY TOMORROW MORNING. HAVE
ADDED VCSH TO THE SITES FOR THE DAY TOMORROW.
PREV DISCUSSION... /ISSUED 331 PM EST MON JAN 4 2016/
DISCUSSION...
A RARE COOL DAY THIS WINTER SEASON ACROSS SOUTH FLORIDA WITH TEMPS
MOST LOCALES REMAINING IN THE 60S...AND A FEW REACHING 70F ACROSS
THE EAST COAST METRO. VERY DRY AIR HAS ADVECTED DOWN THE PENINSULA
WITH DEWPOINTS INTO THE 30S AND 40S.
HIGH PRESSURE RIDGE NORTH OF THE AREA WILL PULL EAST AND ALLOW
WINDS TO QUICKLY TURN NORTHEASTERLY ACROSS SOUTH FLORIDA. THIS
WILL ALLOW FOR RAPID AIR MASS MODIFICATION WITH ATLANTIC MOISTURE
MOVING ONSHORE FROM EAST TO WEST LATE TONIGHT. WINDS WILL INCREASE
OUT OF THE NORTHEAST INTO THE 20-25 KT RANGE OVER THE ATLANTIC.
EXCELLENT SURFACE CONVERGENCE IS FORECAST TO RESULT IN SOME FAST
MOVING SHOWERS MOVING ONSHORE THE ATLANTIC COAST LATE TONIGHT THEN
HITTING AREAS FURTHER INLAND AS WELL ON TUESDAY.
THIS COULD BE THE FIST NIGHT THIS WINTER SEASON THAT THE EAST
COAST CLIMATE SITES FALL BELOW 60F, BUT NOT A CERTAINTY. MUCH WILL
DEPEND ON WHEN THE MODIFICATION OFF THE WARM GULF STREAM
COMMENCES. EITHER WAY, IT WILL FEEL COOL GIVEN HOW WARM WE HAVE
BEEN!
ANOTHER SHORTWAVE IS PROJECTED TO SPAWN LOW PRESSURE DEVELOP TO
OUR SOUTHEAST ON WEDNESDAY. HOW CLOSE THIS LOW DEVELOPS TO SE
FLORIDA WILL DETERMINE HOW MUCH RAIN WILL FALL...BUT MODEL
CONSENSUS IS ZONING IN ON A WET DAY AS MOISTURE GETS TOSSED AROUND
THE LOW AND FOCUSING ON SOUTHEAST FLORIDA WITH GOOD COASTAL
CONVERGENCE SETTING UP THERE. RAINFALL AMOUNTS ARE FORECAST TO BE
0.5-1.0" ACROSS SE FLORIDA...LESSENING INTERIOR/GULF COAST. WILL
HAVE TO MONITOR FOR A LOCALIZED POTENTIAL FOCUS FOR HEAVY
RAINFALL, PARTICULARLY ACROSS MIAMI-DADE.
THE SHORTWAVE MOVES OUT WITH DRYING CONDITIONS ON THURSDAY AHEAD
OF THE NEXT WEATHER MAKER FOR FRIDAY AND INTO THE
WEEKEND...ANOTHER GULF OF MEXICO SHORTWAVE TRAVERSING IN THE
ACTIVE SOUTHERN STREAM. THIS WILL BRING ANOTHER ROUGH OF SHOWERS
TO THE AREA. A FEW THUNDERSTORMS ARE POSSIBLE...EVEN WITH THE
WEDNESDAY SYSTEM, BUT PROBABILITIES TOO LOW TO INCLUDE IN THE
FORECAST EXCEPT OVER THE WARM GULF STREAM CURRENT WHERE
INSTABILITY WILL BE HIGHEST.
TEMPS/HUMIDITY WILL MODERATE MID-LATE WEEK...GOING BACK ABOVE
AVERAGE, BUT NOT AS MUCH AS RECENT WEEKS AND NOT AS HUMID EITHER
WITH 60-DEGREE DEWPOINTS RETURNING MID-LATE WEEK, NOT THE 70S.
INCREASING ONSHORE WINDS ALONG THE ATLANTIC COAST WILL RESULT IN
RIP CURRENT FORMATION AT THE ATLANTIC BEACHES TUE-WED...AND A HIGH
RISK OF RIP CURRENTS IS FORECAST THEN. /GREGORIA
MARINE...
NORTH WINDS WILL BECOME NORTHEAST WHILE INCREASE TO 20+ KNOTS
OVERNIGHT-TUE, LEADING TO RAPIDLY BUILDING SEAS, ESPECIALLY IN THE
GULF STREAM. A SMALL CRAFT ADVISORY CONTINUES IN EFFECT FOR ALL
LOCAL WATERS LATE TONIGHT-TUESDAY AND WILL NEED TO BE EXTENDED FOR
ESPECIALLY THE GULF STREAM BEYOND THIS TIME FRAME AS SEAS WILL
REMAIN ELEVATED THROUGH WED.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 66 73 63 79 / 40 80 60 20
FORT LAUDERDALE 66 73 63 79 / 60 80 50 10
MIAMI 64 74 63 79 / 60 80 50 10
NAPLES 58 71 59 77 / 40 70 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR AMZ610-630-
650-651-670-671.
GM...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR GMZ656-657-
676.
&&
$$
SHORT TERM...52/PS
LONG TERM....88/ALM
AVIATION...52/PS
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1132 PM CST MON JAN 4 2016
.UPDATE...
ISSUED AT 835 PM CST MON JAN 4 2016
Quiet weather is expected across central and southeast Illinois
overnight as a ridge of high pressure crosses the area. The main
weather feature of note is a plume of clouds streaming southwest
across parts of central Illinois from Lake Michigan. The other low
clouds that had been across the area faded with the loss of
diurnal heating. 00Z ILX and forecast soundings indicate a strong
capping inversion around 850 mb, which is about the height of the
lake clouds. The flow beneath this inversion is progged to turn
easterly within the next hour or two, and southerly by morning.
These shifting winds should help to remove these clouds from the
local area within the next few hours. The mostly clear skies and
light winds expected over the area for the rest of the night will
provide good radiational cooling conditions. This will allow
temperatures to fall a few degrees cooler than the past couple
nights, but overnight lows are still expected to be above normal
for early January.
Going forecast is in good shape overall. Updated sky grids to
better depict the lake clouds and their expected disposition.
Otherwise, only made a few hourly grid tweaks for the latest and
expected overnight trends.
&&
.SHORT TERM...(Tonight)
ISSUED AT 240 PM CST MON JAN 4 2016
Earlier hole in the stratocumulus has filled in across much of the
forecast area this afternoon, due to diurnal development and
additional clouds advecting in from Lake Michigan. Latest NAM 925 mb
humidity guidance suggesting the mostly cloudy trend to persist
through about 9 pm before clearing out, while the HRRR scatters the
clouds out closer to 6 pm. With the diurnal nature of most of the
clouds, leaned more toward the faster solution. As ridge axis pushes
east across the state, winds will trend toward the southeast after
midnight. Most locations should fall into the lower 20s overnight,
but some teens likely across the I-74 corridor.
.LONG TERM...(Tuesday through Monday)
ISSUED AT 240 PM CST MON JAN 4 2016
Quiet weather pattern to hold across the area through Wednesday
evening as upper level heights build over the Midwest allowing
warmer air to filter back into the region. Temperatures will
moderate a few degrees on Tuesday with the stronger return flow
setting up Tuesday night into Wednesday. This should push temps
Wednesday afternoon to around 40 degrees with the above normal
temperatures holding into Saturday. The storm system that is slated
to push out of the Southern Plains later Wednesday will begin to
spread precip into our area by Thursday morning. If the precip does
arrive before dawn Thursday, most of the forecast models suggest
more of a rain or freezing rain threat across our far northern
areas. For now, will keep it rain or snow and refine any precip
type issues as we draw closer to the event. The better rain
chances will move in late Thursday, Thursday night into Friday as
the main area of forcing/lift from the southern stream wave
pushes across our area, with rainfall amounts still looking to be
around one half inch.
As the storm system shifts to our northeast on Saturday, colder air
poised to our northwest will shift southeast into the region with
steady or slowly falling temperatures for the afternoon. We will
still have low chance POPs going during the day with a transition
from rain, to a rain snow mixture as the colder air filters in
during the afternoon as gusty northwest winds build in. Much colder
air will shift into the area Saturday night and Sunday accompanied
by gusty northwest winds. Most models suggest 850 temps of around
-20C by late Saturday night or Sunday as the center of the cold
air mass slides southeast into our area. This should result in
morning lows of 10 to 20 degrees by Monday morning with daytime
highs struggling mostly through the 20s Monday afternoon with the
below normal temperatures expected to hold through most of next
week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
ISSUED AT 1127 PM CST MON JAN 4 2016
Quiet/VFR conditions expected across the central Illinois
terminals through the 06Z TAF valid time. The low level flow has
veered sufficiently to blow the lake effect clouds over parts of
northern Illinois away from KBMI & KCMI. The remaining TAF sites
have been clear since the diurnal clouds faded earlier this
evening. Mostly clear skies should prevail for the duration of
the night and into Tuesday. Some high level CIGs should spread
into the area tomorrow ahead of a slowly approaching storm system,
but they should have no impact of flight operations. Variable
winds tonight with a high pressure ridge in the vicinity will
trend southerly and increase Tuesday as the high departs and low
pressure approaches.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...BAK
SHORT TERM...Geelhart
LONG TERM...Smith
AVIATION...BAK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1219 AM MST TUE JAN 5 2016
.UPDATE...
ISSUED AT 1020 PM MST MON JAN 4 2016
UPDATE ISSUED TO ACCOUNT FOR LATEST CLOUD COVER TREND BASED OFF OF
CURRENT 11U-3.9U SATELLITE LOOP. REGION WILL CONTINUE TO SEE
INCREASED HIGH CLOUD COVER THRU THE OVERNIGHT AS SHIELD LIFTS OUT
OF SE COLORADO. OTHER CLOUD COVER ISSUE FOR TONIGHT WAS THE
WESTWARD PUSH/EXTENT OF THE LOW CLOUD DECK CURRENTLY EAST OF THE
HILL CITY AREA. LAST HOUR OR SO THIS DECK HAS BEEN TRUDGING WEST
AND DO THINK IT WILL CLIP PORTIONS OF RED WILLOW...DECATUR...
NORTON AND GRAHAM COUNTIES FOR A FEW HOURS. REST OF FORECAST IS ON
TRACK WITH ONLY SOME PATCHY FREEZING FOG IN PORTIONS OF THE
EASTERN CWA.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 1245 PM MST MON JAN 4 2016
A RIDGE WILL REMAIN OVER THE PLAINS TONIGHT AND THEN SHIFT EAST
TUESDAY WITH SOUTHWEST FLOW ACROSS THE REGION. SURFACE HIGH PRESSURE
WILL REMAIN OVER THE PLAINS TONIGHT. HIGH PRESSURE WILL MOVE EAST
TUESDAY AS A SURFACE TROUGH MOVES INTO EASTERN COLORADO.
THE FORECAST WILL REMAIN DRY TONIGHT DUE TO SUBSIDENCE. A SHORTWAVE
WILL MOVE ACROSS THE FA TUESDAY BUT FORCING AND MOISTURE ARE BOTH
LACKING. POPS WILL BE NIL TONIGHT AND TUESDAY.
THE HRRR INDICATES THE POSSIBILITY OF SOME PATCHY FREEZING FOG EARLY
TUESDAY MORNING FOR A FEW HOURS NEAR NORTON AND GRAHAM COUNTIES.
CONFIDENCE IS RATHER LOW BUT CANNOT RULE IT OUT. PLAN TO INSERT SOME
PATCHY FREEZING FOG IN THAT AREA.
MIN TEMPERATURES TONIGHT SHOULD FALL BACK TO THE TEENS IN EASTERN
COLORADO WITH LOWER 20S ELSEWHERE. MAX TEMPERATURES TUESDAY SHOULD
REACH THE MID 40S.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 1214 AM MST TUE JAN 5 2016
LIGHT SNOW WILL CONTINUE THROUGH FRIDAY NIGHT AS THE SHORTWAVE
TROUGH MOVES THROUGH THE SOUTHERN PLAINS. ADDITIONAL ACCUMULATIONS
CURRENTLY LOOK TO BE AROUND AN INCH DURING THAT TIME. THE
REMAINDER OF THE LONG TERM PERIOD WILL HAVE A DEEP TROUGH NEAR THE
GREAT LAKES RESULTING IN NORTHERLY FLOW ALOFT OVER THE CENTRAL
PLAINS. THERE WILL BE A COUPLE OF WEAK DISTURBANCES IN THE FLOW
BUT MOISTURE WILL BE LACKING FOR ANY SIGNIFICANT SNOWFALL
CHANCES. TEMPERATURES WILL BE BELOW NORMAL...BUT MODEL TRENDS KEEP
THE CORE OF THE COLDEST AIR EAST OF THE LOCAL AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1020 PM MST MON JAN 4 2016
FOR KGLD...VFR CONDITIONS THRU FORECAST PERIOD WITH BKN200
TRENDING DOWN TO BKN090 BY 00Z WEDNESDAY. WINDS SSW 10-20KT WITH
GUSTS NEAR 30KTS BETWEEN 14Z TUES AND 00Z WEDNESDAY.
FOR KMCK...MAINLY VFR CONDITIONS THRU FORECAST PERIOD WITH
BKN100-200. LIFR POSSIBLE OVC004 FROM 07Z-09Z. WINDS SE AROUND
10KTS THRU 15Z...THEN SOUTH 10-20KTS BECOMING SE AROUND 10KTS
AGAIN BY 23Z TUESDAY.
BOTH SITES COULD SEE LOW LEVEL WIND SHEAR 06Z-15Z FROM THE SOUTH
AROUND 40 KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JN
SHORT TERM...FS
LONG TERM...024
AVIATION...JN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1021 PM MST MON JAN 4 2016
.UPDATE...
ISSUED AT 1020 PM MST MON JAN 4 2016
UPDATE ISSUED TO ACCOUNT FOR LATEST CLOUD COVER TREND BASED OFF OF
CURRENT 11U-3.9U SATELLITE LOOP. REGION WILL CONTINUE TO SEE
INCREASED HIGH CLOUD COVER THRU THE OVERNIGHT AS SHIELD LIFTS OUT
OF SE COLORADO. OTHER CLOUD COVER ISSUE FOR TONIGHT WAS THE
WESTWARD PUSH/EXTENT OF THE LOW CLOUD DECK CURRENTLY EAST OF THE
HILL CITY AREA. LAST HOUR OR SO THIS DECK HAS BEEN TRUDGING WEST
AND DO THINK IT WILL CLIP PORTIONS OF RED WILLOW...DECATUR...
NORTON AND GRAHAM COUNTIES FOR A FEW HOURS. REST OF FORECAST IS ON
TRACK WITH ONLY SOME PATCHY FREEZING FOG IN PORTIONS OF THE
EASTERN CWA.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 1245 PM MST MON JAN 4 2016
A RIDGE WILL REMAIN OVER THE PLAINS TONIGHT AND THEN SHIFT EAST
TUESDAY WITH SOUTHWEST FLOW ACROSS THE REGION. SURFACE HIGH PRESSURE
WILL REMAIN OVER THE PLAINS TONIGHT. HIGH PRESSURE WILL MOVE EAST
TUESDAY AS A SURFACE TROUGH MOVES INTO EASTERN COLORADO.
THE FORECAST WILL REMAIN DRY TONIGHT DUE TO SUBSIDENCE. A SHORTWAVE
WILL MOVE ACROSS THE FA TUESDAY BUT FORCING AND MOISTURE ARE BOTH
LACKING. POPS WILL BE NIL TONIGHT AND TUESDAY.
THE HRRR INDICATES THE POSSIBILITY OF SOME PATCHY FREEZING FOG EARLY
TUESDAY MORNING FOR A FEW HOURS NEAR NORTON AND GRAHAM COUNTIES.
CONFIDENCE IS RATHER LOW BUT CANNOT RULE IT OUT. PLAN TO INSERT SOME
PATCHY FREEZING FOG IN THAT AREA.
MIN TEMPERATURES TONIGHT SHOULD FALL BACK TO THE TEENS IN EASTERN
COLORADO WITH LOWER 20S ELSEWHERE. MAX TEMPERATURES TUESDAY SHOULD
REACH THE MID 40S.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 157 PM MST MON JAN 4 2016
THE UPPER SHORT WAVE TROUGH WILL CONTINUE TO LIFT OUT ACROSS THE
CENTRAL HIGH PLAINS REGION TUESDAY NIGHT AND WEDNESDAY MORNING
WITH THE SURFACE TROUGH PUSHING FAR ENOUGH EAST THAT PRECIPITATION
ASSOCIATED WITH THE OPEN WAVE WILL LIKELY REMAIN SOUTH AND EAST
OF THE FORECAST AREA. THERE WILL BE BRIEF SHORT WAVE RIDGING ALOFT
WEDNESDAY AND WEDNESDAY NIGHT WITH DRY CONDITIONS.
A SURFACE LOW REDEVELOPS OVER SOUTHEAST COLORADO AHEAD OF THE
NEXT TROUGH THAT MOVES ACROSS THE FORECAST AREA THURSDAY INTO
THURSDAY EVENING. THE SOUTHERLY FETCH OF GULF MOISTURE STREAMING
INTO THE PLAINS STATES TURNS IT`S FOCUS ON THE CENTRAL HIGH PLAINS
WITH A MORE SOUTHEASTERLY FLOW AS THE SURFACE LOW MOVES INTO THE
PANHANDLE REGION. MOISTURE INCREASES IN THE COLUMN THURSDAY...BUT
INITIALLY REMAINS DRYER BETWEEN 850-700MB...SO PRECIPITATION THAT
MOVES INTO THE AREA EARLY THURSDAY MORNING LOOKS LIKE IT MAY START
AS FREEZING DRIZZLE BEFORE SURFACE TEMPERATURES WARM DURING THE
DAY AND THE COLUMN APPROACHES SATURATION AROUND 18Z. THE SURFACE
LOW MOVES INTO SOUTHEAST KANSAS BY THURSDAY NIGHT WITH
TEMPERATURES FALLING AND QUICKLY CHANGING PRECIPITATION OVER TO
ALL SNOW. THE LOW MOVES INTO NORTHERN MISSOURI BY
FRIDAY...BRINGING THE LIGHT SNOW TO AN END FROM WEST TO EAST BY
FRIDAY NIGHT.
BEYOND FRIDAY...MODEL SOLUTIONS FALL OUT OF AGREEMENT. HOWEVER...BOTH
THE ECMWF AND GFS SHOW STRONG SURFACE COLD AIR ADVECTION AS THE
MAIN UPPER FLOW MOVES WELL SOUTH OVER NORTHERN MEXICO...SURFACE
HIGH PRESSURE MOVES INTO THE REGION SATURDAY AND CONTINUES INTO
THE SOUTHERN PLAINS ON SUNDAY. LOW TEMPERATURES IN THE SINGLE
DIGITS...AND POSSIBLY BELOW ZERO...MAY BE OBSERVED THROUGH THE
WEEKEND WITH HIGH TEMPERATURES ONLY REACHING INTO THE UPPER TEENS
TO MIDDLE 20S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1020 PM MST MON JAN 4 2016
FOR KGLD...VFR CONDITIONS THRU FORECAST PERIOD WITH BKN200
TRENDING DOWN TO BKN090 BY 00Z WEDNESDAY. WINDS SSW 10-20KT WITH
GUSTS NEAR 30KTS BETWEEN 14Z TUES AND 00Z WEDNESDAY.
FOR KMCK...MAINLY VFR CONDITIONS THRU FORECAST PERIOD WITH
BKN100-200. LIFR POSSIBLE OVC004 FROM 07Z-09Z. WINDS SE AROUND
10KTS THRU 15Z...THEN SOUTH 10-20KTS BECOMING SE AROUND 10KTS
AGAIN BY 23Z TUESDAY.
BOTH SITES COULD SEE LOW LEVEL WIND SHEAR 06Z-15Z FROM THE SOUTH
AROUND 40 KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JN
SHORT TERM...FS
LONG TERM...LOCKHART
AVIATION...JN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
456 AM EST TUE JAN 5 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 455 AM EST TUE JAN 5 2016
WV IMAGERY AND RAP ANALYSIS INDICATED MID/UPPER LEVEL RIDGING FROM
THE UPPER MS VALLEY INTO THE WRN GREAT LAKES. AT THE SFC...A TIGHT
PRES GRADIENT AND STRONG SW FLOW PREVAILED OVER LAKE SUPERIOR AND
UPPER MI BTWN HIGH PRES OVER THE ERN LAKES AND FRONT/TROUGH FROM NW
ONTARIO INTO THE NRN PLAINS. MOISTENING WITH THE SW WIND ACROSS LAKE
MI HAS BROUGH LOW CLOUDS INTO FAR ERN UPPER MI...S AND E FROM ISQ TO
ERY. A BAND OF CLOUDS HAS ALSO DEVELOPED NE FROM THE BAY OF GREEN
BAY. UPSTREAM A LARGER AREA OF LOW CLOUDS FROM ERN MN AND FAR WRN WI
WAS GRADUALLY LIFTING TO THE NNE TO HYR-EAU.
TODAY...HIGH RES MODELS 925 MB RH FCSTS...IN LINE WITH CURRENT
TRENDS...SUGGEST THAT THE CLOUDS OVER NW WI WILL GRADUALLY SPREAD
INTO THE SW PORTION OF UPPER MI TODAY BUT THIN OUT OVER CNTRL
AREAS...ESPECIALLY WHERE DOWNSLOPE SW WINDS PREVAIL. THE CLOUDS OVER
THE ERN CWA ARE EXPECTED TO PUSH FARTHER TO THE EAST. EVEN WITH
LIMITED DAYTIME MIXING AS TEMPS CLIMB INTO THE UPPER 20S TO AROUND
30...WINDS WILL BECOME GUSTY TO AROUND 25-30 MPH.
TONIGHT...A SHORTWAVE TROUGH MOVING THROUGH NRN ONTARIO WILL HELP
DRAG A WEAK COLD FRONT INTO LAKE SUPERIOR. 850-700 MB FGEN
ASSOCIATED WITH THE FRONT ALONG WITH WEAK ISENTROPIC LIFT ALONG WITH
MOISTENING FROM WSW WINDS ACROSS LAKE SUPERIOR WILL SUPPORT A SLIGHT
CHANCE FOR LIGHT SNOW SHOWERS OR FLURRIES INTO THE KEWEENAW. WITH
THE MOIST LAYER ONLY TO AROUND -10C...SOME FZDZ MAY ALSO BE
POSSIBLE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 306 AM EST TUE JAN 5 2016
MAY SEE A FEW LIGHT LES SHOWERS OVER THE NRN PORTIONS OF THE
KEWEENAW WED MORNING WITH SW WINDS AND 850MB TEMPS AROUND -9C...BUT
NOT SIGNIFICANT ACCUMULATIONS. A TROUGH AND SFC FRONT STALL OUT OVER
THE AREA ON WED AND STAY INTO THU NIGHT. DEVELOPMENT OF LOW-MID
LEVEL FGEN FORCING WILL PROMOTE AN ELONGATED AREA OF LIGHT SNOW OVER
MAINLY WRN/NWRN UPPER MI WED AFTERNOON AND EVENING. A SHORTWAVE AND
WAA WILL THEN LEAD TO WIDESPREAD LIGHT SNOW WED NIGHT INTO
THU...ENDING TIME UNCERTAIN WITH DIFFERING MODEL SOLUTIONS. EXPECT
SNOW TO LIQUID RATIOS AROUND 10 TO 1 GIVEN MOST OF THE WEAK LIFT IS
BELOW THE DGZ...WHICH WHEN COMBINED WITH TOTAL QPF AMOUNTS OF 0.10-
0.25 INCHES (LOWEST SE AND GREATEST OVER THE W AND NW) EXPECT
GENERALLY 1 TO JUST OVER 2 INCHES OF SNOW IN THE 24-30 HOUR PERIOD.
ANOTHER PERIOD OF LIGHT AND INSIGNIFICANT SNOW IS EXPECTED FRI AND
SAT AS A WEAK LOW MOVES FROM MO AT 12Z FRI TO QUEBEC OR JAMES BAY
(DEPENDING ON MODEL SOLUTION) BY 00Z SUN. STILL LOOKS LIKE BEST
FORCING/PRECIP WILL BE OVER THE ERN AND MAYBE SRN UPPER MI IN THE
FRI AFTERNOON/FRI NIGHT TIME FRAME. STILL SEEING MODEL DIFFERENCES
ON TIMING. COULD SEE SOME RAIN MIX IN FRI AFTERNOON OVER SERN UPPER
MI AS WET BULB ZERO HEIGHTS RISE WITH HIGHS IN THE MID 30S. OVERALL
ONLY EXPECTING A VERY MINOR 1-3 INCHES OF SNOW OVER 36 HOURS.
MAIN STORY IN THE LONG TERM IS THAT MODEL PERSIST IN SHOWING AN
ACTIVE WAVE MOVING INTO THE AREA SAT NIGHT AND DEEPENING INTO A
CLOSED UPPER LOW OVER OR NEAR THE CWA LATE SUN AND SUN NIGHT. 850MB
TEMPS AS LOW AS -25C ARE CO-LOCATED WITH THE LOW. MODELS ALSO
CONTINUE TO SHOW ANOTHER WAVE MOVING IN MID NEXT WEEK...WHICH WILL
REINFORCE THE COLD AIR. TEMPS WILL GO FROM HIGHS IN THE UPPER 20S TO
MID 30S AND LOWS IN THE 20S LATE IN THE WEEK TO HIGHS IN THE SINGLE
DIGITS TO TEENS ABOVE ZERO AND LOWS IN THE SINGLE DIGITS ABOVE AND
BELOW ZERO EARLY NEXT WEEK. NW-W WIND SNOWBELTS WILL CERTAINLY SEE
PERSISTENT LES SAT NIGHT THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...BUT NOT EXPECTING WARNING AMOUNTS AT THIS TIME DUE TO SMALL
FLAKE SIZE GIVEN VERY COLD TEMPS (CLOUD LAYER COLDER THAN THE
PREFERRED DGZ). THAT COLD AIR WILL ALSO MARK THE FIRST TIME OUR
OFFICE WILL FALL BELOW ZERO SINCE MARCH 28...2015. THROUGH JANUARY
3...THAT MAKES A 281 DAY STREAK AND IS CURRENTLY TIED FOR THE 16TH
LONGEST STREAK. IF THE CURRENT FORECAST HOLDS...WE WILL MAKE IT TO
AROUND 288 OR 289 DAYS...WHICH WOULD BE RIGHT AROUND THE 9TH LONGEST
STREAK OF TEMPERATURES AT OR ABOVE ZERO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1236 AM EST TUE JAN 5 2016
INCRSG SW WIND TNGT ABOVE LLVL INVRN ENHANCED BY NOCTURNAL COOLING
WL RESULT IN LLWS AT ALL 3 SITES THIS MRNG. WITH SOME DAYTIME
HEATING...EXPECT GUSTY SW WINDS BY LATE MRNG THRU THE AFTN. HOW
QUICKLY THIS SW FLOW TAPS MOISTER AIR WELL TO THE SW OF UPR MI IS
ANOTHER FCST CONCERN. RIGHT NOW...EXPECT VFR CONDITIONS TO PREVAIL
THRU TODAY...WITH DOWNSLOPE NATURE OF THE SW FLOW HELPING TO
MAINTAIN LOWER RH. BUT EVEN THE DRIER GUIDANCE HINTS LO CLDS WL
ARRIVE TNGT...SO FCST MVFR CIGS TO ARRIVE THIS EVNG.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EST MON JAN 4 2016
TIGHTENING PRES GRADIENT BTWN DEPARTING HIGH PRES RIDGE AND LOW PRES
MOVING OVER HUDSON BAY WILL RESULT IN SW WINDS INCREASING TO GALES
TONIGHT ACROSS LAKE SUPERIOR. THE GALES WILL CONTINUE TUE BEFORE
WINDS BEGIN TO DIMINISH TUE NIGHT. WINDS WILL DIMINISH FURTHER
WED/THU TO MOSTLY UNDER 20KT AS A LOW PRES TROF SETTLES OVER THE
UPPER GREAT LAKES. WINDS WILL INCREASE SOME ON FRI/SAT AS LOW PRES
LIFTS NE INTO THE GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ265>267.
GALE WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR LSZ162.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LSZ263-264.
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ243-244.
LAKE MICHIGAN...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
308 AM EST TUE JAN 5 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 359 PM EST MON JAN 4 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW THAT THE TROF THAT DROPPED
INTO THE GREAT LAKES REGION OVER THE WEEKEND IS WEAKENING AND
QUICKLY SHIFTING INTO NEW ENGLAND IN RESPONSE TO A STRONG RIDGE
MOVING OUT OVER THE PLAINS AND SCNTRL CANADA. 12HR 500MB HEIGHT
RISES WERE 90M/160M AT KINL/CWPL RESPECTIVELY AT 12Z TODAY. THE
ASSOCIATED SFC HIGH PRES RIDGE IS ALREADY EXITING TO THE E OF THE
FCST AREA AND SW RETURN FLOW IS RAPIDLY INCREASING TO THE W AND NW
IN THE TIGHTENING PRES GRADIENT BTWN THE DEPARTING RIDGE AND LOW
PRES APPROACHING HUDSON BAY. AS A RESULT...LINGERING/DIMINISHING LES
OFF LAKE SUPERIOR HAS MOSTLY SHIFTED OFFSHORE EARLY THIS AFTN WITH
ONLY A FEW RESIDUAL FLURRIES OVER THE NCNTRL. FLURRIES HAVE ALSO
MOVED ONSHORE AROUND MENOMINEE AS WINDS VEER OVER NRN LAKE MI.
A QUIET SHORT TERM PORTION OF THE FCST IS SHAPING UP...AT LEAST PCPN-
WISE. SW FLOW WILL DOMINATE BTWN THE HIGH PRES RIDGE SHIFTING TO THE
E COAST AND LOW PRES TRACKING ACROSS HUDSON BAY. DESPITE
WAA/ISENTROPIC ASCENT...FCST SOUNDINGS SHOW COLUMN REMAINING VERY
DRY...SO PCPN WON`T BE AN ISSUE UNDER THE WAA REGIME TONIGHT/TUE.
HOWEVER...AS WINDS VEER TO THE SW OVER NRN LAKE MI...SOME FLURRIES
SHOULD BRUSH AREAS NEAR LAKE MI THIS EVENING...AND ONCE THE SW FLOW
LOCKS IN...THE WRN EDGE OF LIGHT LES/FLURRIES MAY OCCASIONALLY
AFFECT SE LUCE COUNTY OVERNIGHT. ELSEHWERE...AN ISSUE TONIGHT/TUE IS
THE POTENTIAL FOR LOW CLOUDS TO DEVELOP AS NAM/RAP SHOW SHALLOW
MOISTENING IN THE NEAR SFC LAYER...THE RAP MUCH SOONER THAN THE NAM.
SFC OBS/3.9 MICRON IMAGERY DO SHOW LOW STRATUS OVER MUCH OF IA INTO
PORTIONS OF SCNTRL MN THIS AFTN. TRAJECTORIES INITIALLY CARRY THIS
STRATUS NORTHWARD...BUT OVER TIME THESE LOW CLOUDS MAY SLIP INTO THE
HIGH TERRAIN OF WRN UPPER MI LATE TONIGHT OR TUE MORNING. WILL WAIT
TO SEE HOW THE STRATUS EVOLVES THIS EVENING WITHIN STRENGTHENING LOW-
LEVEL FLOW BEFORE SHIFTING TO A MUCH MORE PESSIMISTIC SKY COVER FCST
OVER THE HIGHER TERRAIN OF THE W HALF. ON TUE...TIGHT PRES GRADIENT
WILL LEAD TO GUSTY WINDS. LIMITED MIXING DEPTH WILL WORK TO KEEP
WINDS IN CHECK...BUT STILL EXPECT SOME GUSTS TO 30-35MPH OVER THE
HIGHER TERRAIN...DOWNSLOPE AREAS NEAR LAKE SUPERIOR AND DOWNWIND OF
LAKE MICHIGAN.
AS FOR TEMPS...TEMPS WILL HAVE A CHANCE TO FALL INITIALLY THIS
EVENING BEFORE GRADIENT TIGHTENS. TOUGH TO SAY HOW LOW TEMPS WILL
GET...BUT THE FAR E SHOULD HAVE THE BEST CHANCE FOR A QUICK FALL
THIS EVENING BEFORE CLOUDS AND/OR WINDS INCREASE AS THAT AREA IS
CLOSER TO THE DEPARTING HIGH PRES RIDGE. WILL SHOW TEMPS AS LOW AS
AROUND 5F ABOVE IN LUCE COUNTY/PORTIONS OF SCHOOLCRAFT COUNTY.
TRADITIONAL COLD SPOTS OVER THE INTERIOR W SHOULD SLIP JUST BLO 10F.
EXPECT HIGHS ON TUE IN THE MID/UPPER 20S FOR THE MOST PART.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 306 AM EST TUE JAN 5 2016
MAY SEE A FEW LIGHT LES SHOWERS OVER THE NRN PORTIONS OF THE
KEWEENAW WED MORNING WITH SW WINDS AND 850MB TEMPS AROUND -9C...BUT
NOT SIGNIFICANT ACCUMULATIONS. A TROUGH AND SFC FRONT STALL OUT OVER
THE AREA ON WED AND STAY INTO THU NIGHT. DEVELOPMENT OF LOW-MID
LEVEL FGEN FORCING WILL PROMOTE AN ELONGATED AREA OF LIGHT SNOW OVER
MAINLY WRN/NWRN UPPER MI WED AFTERNOON AND EVENING. A SHORTWAVE AND
WAA WILL THEN LEAD TO WIDESPREAD LIGHT SNOW WED NIGHT INTO
THU...ENDING TIME UNCERTAIN WITH DIFFERING MODEL SOLUTIONS. EXPECT
SNOW TO LIQUID RATIOS AROUND 10 TO 1 GIVEN MOST OF THE WEAK LIFT IS
BELOW THE DGZ...WHICH WHEN COMBINED WITH TOTAL QPF AMOUNTS OF 0.10-
0.25 INCHES (LOWEST SE AND GREATEST OVER THE W AND NW) EXPECT
GENERALLY 1 TO JUST OVER 2 INCHES OF SNOW IN THE 24-30 HOUR PERIOD.
ANOTHER PERIOD OF LIGHT AND INSIGNIFICANT SNOW IS EXPECTED FRI AND
SAT AS A WEAK LOW MOVES FROM MO AT 12Z FRI TO QUEBEC OR JAMES BAY
(DEPENDING ON MODEL SOLUTION) BY 00Z SUN. STILL LOOKS LIKE BEST
FORCING/PRECIP WILL BE OVER THE ERN AND MAYBE SRN UPPER MI IN THE
FRI AFTERNOON/FRI NIGHT TIME FRAME. STILL SEEING MODEL DIFFERENCES
ON TIMING. COULD SEE SOME RAIN MIX IN FRI AFTERNOON OVER SERN UPPER
MI AS WET BULB ZERO HEIGHTS RISE WITH HIGHS IN THE MID 30S. OVERALL
ONLY EXPECTING A VERY MINOR 1-3 INCHES OF SNOW OVER 36 HOURS.
MAIN STORY IN THE LONG TERM IS THAT MODEL PERSIST IN SHOWING AN
ACTIVE WAVE MOVING INTO THE AREA SAT NIGHT AND DEEPENING INTO A
CLOSED UPPER LOW OVER OR NEAR THE CWA LATE SUN AND SUN NIGHT. 850MB
TEMPS AS LOW AS -25C ARE CO-LOCATED WITH THE LOW. MODELS ALSO
CONTINUE TO SHOW ANOTHER WAVE MOVING IN MID NEXT WEEK...WHICH WILL
REINFORCE THE COLD AIR. TEMPS WILL GO FROM HIGHS IN THE UPPER 20S TO
MID 30S AND LOWS IN THE 20S LATE IN THE WEEK TO HIGHS IN THE SINGLE
DIGITS TO TEENS ABOVE ZERO AND LOWS IN THE SINGLE DIGITS ABOVE AND
BELOW ZERO EARLY NEXT WEEK. NW-W WIND SNOWBELTS WILL CERTAINLY SEE
PERSISTENT LES SAT NIGHT THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...BUT NOT EXPECTING WARNING AMOUNTS AT THIS TIME DUE TO SMALL
FLAKE SIZE GIVEN VERY COLD TEMPS (CLOUD LAYER COLDER THAN THE
PREFERRED DGZ). THAT COLD AIR WILL ALSO MARK THE FIRST TIME OUR
OFFICE WILL FALL BELOW ZERO SINCE MARCH 28...2015. THROUGH JANUARY
3...THAT MAKES A 281 DAY STREAK AND IS CURRENTLY TIED FOR THE 16TH
LONGEST STREAK. IF THE CURRENT FORECAST HOLDS...WE WILL MAKE IT TO
AROUND 288 OR 289 DAYS...WHICH WOULD BE RIGHT AROUND THE 9TH LONGEST
STREAK OF TEMPERATURES AT OR ABOVE ZERO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1236 AM EST TUE JAN 5 2016
INCRSG SW WIND TNGT ABOVE LLVL INVRN ENHANCED BY NOCTURNAL COOLING
WL RESULT IN LLWS AT ALL 3 SITES THIS MRNG. WITH SOME DAYTIME
HEATING...EXPECT GUSTY SW WINDS BY LATE MRNG THRU THE AFTN. HOW
QUICKLY THIS SW FLOW TAPS MOISTER AIR WELL TO THE SW OF UPR MI IS
ANOTHER FCST CONCERN. RIGHT NOW...EXPECT VFR CONDITIONS TO PREVAIL
THRU TODAY...WITH DOWNSLOPE NATURE OF THE SW FLOW HELPING TO
MAINTAIN LOWER RH. BUT EVEN THE DRIER GUIDANCE HINTS LO CLDS WL
ARRIVE TNGT...SO FCST MVFR CIGS TO ARRIVE THIS EVNG.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EST MON JAN 4 2016
TIGHTENING PRES GRADIENT BTWN DEPARTING HIGH PRES RIDGE AND LOW PRES
MOVING OVER HUDSON BAY WILL RESULT IN SW WINDS INCREASING TO GALES
TONIGHT ACROSS LAKE SUPERIOR. THE GALES WILL CONTINUE TUE BEFORE
WINDS BEGIN TO DIMINISH TUE NIGHT. WINDS WILL DIMINISH FURTHER
WED/THU TO MOSTLY UNDER 20KT AS A LOW PRES TROF SETTLES OVER THE
UPPER GREAT LAKES. WINDS WILL INCREASE SOME ON FRI/SAT AS LOW PRES
LIFTS NE INTO THE GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ263>267.
GALE WARNING UNTIL 10 PM EST /9 PM CST/ THIS EVENING FOR LSZ162.
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ243-244.
LAKE MICHIGAN...
GALE WARNING FROM 7 AM THIS MORNING TO 1 AM EST WEDNESDAY FOR
LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1236 AM EST TUE JAN 5 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 359 PM EST MON JAN 4 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW THAT THE TROF THAT DROPPED
INTO THE GREAT LAKES REGION OVER THE WEEKEND IS WEAKENING AND
QUICKLY SHIFTING INTO NEW ENGLAND IN RESPONSE TO A STRONG RIDGE
MOVING OUT OVER THE PLAINS AND SCNTRL CANADA. 12HR 500MB HEIGHT
RISES WERE 90M/160M AT KINL/CWPL RESPECTIVELY AT 12Z TODAY. THE
ASSOCIATED SFC HIGH PRES RIDGE IS ALREADY EXITING TO THE E OF THE
FCST AREA AND SW RETURN FLOW IS RAPIDLY INCREASING TO THE W AND NW
IN THE TIGHTENING PRES GRADIENT BTWN THE DEPARTING RIDGE AND LOW
PRES APPROACHING HUDSON BAY. AS A RESULT...LINGERING/DIMINISHING LES
OFF LAKE SUPERIOR HAS MOSTLY SHIFTED OFFSHORE EARLY THIS AFTN WITH
ONLY A FEW RESIDUAL FLURRIES OVER THE NCNTRL. FLURRIES HAVE ALSO
MOVED ONSHORE AROUND MENOMINEE AS WINDS VEER OVER NRN LAKE MI.
A QUIET SHORT TERM PORTION OF THE FCST IS SHAPING UP...AT LEAST PCPN-
WISE. SW FLOW WILL DOMINATE BTWN THE HIGH PRES RIDGE SHIFTING TO THE
E COAST AND LOW PRES TRACKING ACROSS HUDSON BAY. DESPITE
WAA/ISENTROPIC ASCENT...FCST SOUNDINGS SHOW COLUMN REMAINING VERY
DRY...SO PCPN WON`T BE AN ISSUE UNDER THE WAA REGIME TONIGHT/TUE.
HOWEVER...AS WINDS VEER TO THE SW OVER NRN LAKE MI...SOME FLURRIES
SHOULD BRUSH AREAS NEAR LAKE MI THIS EVENING...AND ONCE THE SW FLOW
LOCKS IN...THE WRN EDGE OF LIGHT LES/FLURRIES MAY OCCASIONALLY
AFFECT SE LUCE COUNTY OVERNIGHT. ELSEHWERE...AN ISSUE TONIGHT/TUE IS
THE POTENTIAL FOR LOW CLOUDS TO DEVELOP AS NAM/RAP SHOW SHALLOW
MOISTENING IN THE NEAR SFC LAYER...THE RAP MUCH SOONER THAN THE NAM.
SFC OBS/3.9 MICRON IMAGERY DO SHOW LOW STRATUS OVER MUCH OF IA INTO
PORTIONS OF SCNTRL MN THIS AFTN. TRAJECTORIES INITIALLY CARRY THIS
STRATUS NORTHWARD...BUT OVER TIME THESE LOW CLOUDS MAY SLIP INTO THE
HIGH TERRAIN OF WRN UPPER MI LATE TONIGHT OR TUE MORNING. WILL WAIT
TO SEE HOW THE STRATUS EVOLVES THIS EVENING WITHIN STRENGTHENING LOW-
LEVEL FLOW BEFORE SHIFTING TO A MUCH MORE PESSIMISTIC SKY COVER FCST
OVER THE HIGHER TERRAIN OF THE W HALF. ON TUE...TIGHT PRES GRADIENT
WILL LEAD TO GUSTY WINDS. LIMITED MIXING DEPTH WILL WORK TO KEEP
WINDS IN CHECK...BUT STILL EXPECT SOME GUSTS TO 30-35MPH OVER THE
HIGHER TERRAIN...DOWNSLOPE AREAS NEAR LAKE SUPERIOR AND DOWNWIND OF
LAKE MICHIGAN.
AS FOR TEMPS...TEMPS WILL HAVE A CHANCE TO FALL INITIALLY THIS
EVENING BEFORE GRADIENT TIGHTENS. TOUGH TO SAY HOW LOW TEMPS WILL
GET...BUT THE FAR E SHOULD HAVE THE BEST CHANCE FOR A QUICK FALL
THIS EVENING BEFORE CLOUDS AND/OR WINDS INCREASE AS THAT AREA IS
CLOSER TO THE DEPARTING HIGH PRES RIDGE. WILL SHOW TEMPS AS LOW AS
AROUND 5F ABOVE IN LUCE COUNTY/PORTIONS OF SCHOOLCRAFT COUNTY.
TRADITIONAL COLD SPOTS OVER THE INTERIOR W SHOULD SLIP JUST BLO 10F.
EXPECT HIGHS ON TUE IN THE MID/UPPER 20S FOR THE MOST PART.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 323 PM EST MON JAN 4 2016
NO SIGNIFICANT WEATHER CONCERNS FOR THE LONG TERM FORECAST...BUT
THERE WILL BE SEVERAL NUISANCE EVENTS THAT COULD LEAD TO OCCASIONAL
PERIODS OF SLIPPERY ROADS.
HIGH PRESSURE WILL BE OVER THE ATLANTIC SEABOARD AT THE START OF
THE LONG TERM PERIOD...WHILE A SHORTWAVE AND SURFACE LOW MOVE
THROUGH SOUTHERN HUDSON BAY. A WEAKENING TROUGH ASSOCIATED WITH THE
LOW WILL BE SLIDING SOUTHEAST TOWARDS THE AREA TUESDAY NIGHT AND
INTO WEDNESDAY (ACROSS NORTHWEST ONTARIO)...EVENTUALLY SETTLING
OVER WESTERN LAKE SUPERIOR. THAT TROUGH WILL REMAIN NEARLY
STATIONARY THROUGH THURSDAY...AS A WEAK SHORTWAVE LIFTS NORTHEAST
ACROSS THE UPPER GREAT LAKES REGION. EXPECT LIMITED PRECIPITATION
ALONG THE FRONT TUESDAY NIGHT INTO WEDNESDAY BEFORE THE SHORTWAVE
MOVES THROUGH...WITH THE BEST CHANCES TIED TO SOME LAKE ENHANCEMENT
NEAR THE KEWEENAW PENINSULA. THE GENERAL IDEA WITH THE HIGHER
RESOLUTION MODELS IS TO KEEP THE TROUGH OVER WESTERN LAKE SUPERIOR
AND THE HEAVIER BAND JUST BRUSHING THE NORTHERN PORTIONS OF
KEWEENAW COUNTY. WILL FOLLOW THAT IDEA WITH THE POPS/SNOW
FORECAST...BUT WILL NEED TO KEEP AN EYE ANY TRENDS TO THE SOUTH AS
THAT WOULD LEAD TO SOME HEAVIER SNOW AFFECTING KEWEENAW COUNTY.
OTHERWISE...EXPECT LOW CLOUDS TO SPREAD INTO THE AREA UNDER THE
STRONG INVERSION JUST ABOVE 900MB TUESDAY EVENING...ASSUMING THEY
DON/T OCCUR BEFORE THAT AS SHOWN ON THE NAM. WITH THE LOW CLOUD
POTENTIAL AND CLOUDS FROM THE TROUGH...SHOULD SEE A MOSTLY CLOUDY
PERIOD TUESDAY NIGHT INTO WEDNESDAY.
PRECIPITATION SHOULD MOVE INTO THE WESTERN U.P. WEDNESDAY
AFTERNOON/EVENING ALONG THE STALLED TROUGH AND ASSOCIATED WITH
INCREASING MOISTURE AND MID LEVEL Q-VECTOR CONVERGENCE WITH THE
SHORTWAVE. WILL LIKELY SEE TWO WAVES...WITH THE FIRST AN ELONGATED
WSW TO ENE AREA OF SNOW STRETCHING ACROSS THE WEST/CENTRAL U.P. AND
ASSOCIATED WITH 850-750MB FGEN FORCING. THE SECOND PUSH ARRIVES
LATE WEDNESDAY NIGHT INTO THURSDAY AS THE SHORTWAVE AND 850-700MB
WARM AIR ADVECTION PUSHES THROUGH. EXPECT ALL OF THIS PRECIP TO
FALL AS SNOW LATE WEDNESDAY AFTERNOON INTO THURSDAY...BUT WITH MUCH
OF THE FORCING BELOW THE DGZ...THINK SNOW-TO-LIQUID RATIOS WILL BE
RIGHT AROUND 10-1 FOR MUCH OF THE EVENT (MAYBE SLIGHTLY LOWER
INITIALLY AND SLIGHTLY HIGHER TOWARDS THE END). THUS...WITH QPF
AMOUNTS OF 0.1 TO 0.25 OVER THE WEST/CENTRAL U.P. WOULD EXPECT
SNOWFALL AMOUNTS AROUND 2 INCHES FOR MUCH OF THE WEST/CENTRAL U.P.
SHOULD SEE A BRIEF BREAK BEFORE THE NEXT WAVE OF LIGHT PRECIPITATION
MOVES NORTHEAST INTO THE AREA FRIDAY INTO SATURDAY AS A WEAK LOW
LIFTS FROM MISSOURI AT 12Z FRIDAY TO JAMES BAY BY 12Z SUNDAY. AT
THIS POINT...IT LOOKS LIKE THE BEST FORCING WILL BE OVER THE EASTERN
U.P. WITH THE BEST PUSH OF SNOW MOVING THROUGH DURING THE DAY ON
FRIDAY (GENERALLY 1-3 INCHES). THERE MAY BE ENOUGH LOW LEVEL WARMING
TO RAISE WETBULB0 HEIGHTS TO LEAD TO A LITTLE BIT OF RAIN MIXING IN
WITH THE SNOW ALONG THE BAY OF GREEN BAY SHORELINE SOUTH OF
ESCANABA...SO DID INCLUDE A SLIGHT CHANCE TO CHANCE OF RAIN THERE.
WHILE THE LOW IS FAIRLY WEAK AND BRINGS SOME LIGHT SNOW FRIDAY
INTO FRIDAY NIGHT...A STRONG WAVE FROM THE ARCTIC WILL BE DIVING
SOUTH ACROSS THE CANADIAN PRAIRIES AND BE MOVING TOWARDS THE GREAT
LAKES REGION FOR THE SECOND HALF OF THE WEEKEND AND FOR EARLY NEXT
WEEK. THAT WILL LEAD TO A SIGNIFICANT TRANSITION IN TEMPERATURES...
FROM THE LOWER 30S FOR THE LATER HALF OF THIS WEEK TO HIGHS IN THE
SINGLE DIGITS TO LOWER TEENS ABOVE ZERO ON MONDAY. THAT COLD AIR
WILL ALSO MARK THE FIRST TIME OUR OFFICE WILL FALL BELOW ZERO SINCE
MARCH 28...2015. THROUGH JANUARY 3...THAT MAKES A 281 DAY STREAK
AND IS CURRENTLY TIED FOR THE 16TH LONGEST STREAK. IF THE CURRENT
FORECAST HOLDS...WE WILL MAKE IT TO AROUND 288 OR 289 DAYS...WHICH
WOULD BE RIGHT AROUND THE 9TH LONGEST STREAK OF TEMPERATURES AT OR
ABOVE ZERO. THAT COLD AIR (850MB TEMPS FALLING TO -24C ON SUNDAY)
WILL KICK THE LAKE EFFECT MACHINE BACK INTO GEAR FOR THE AREA...BUT
THE COLD TEMPERATURES WILL KEEP THE CLOUD GENERALLY ABOVE THE DGZ
LEADING TO SMALLER FLAKES. THAT WILL KEEP SNOWFALL AMOUNTS IN CHECK
AND LIKELY WOULD ONLY SEE ADVISORY AMOUNTS IN THE TRADITIONAL
WEST-NORTHWEST WIND SNOWBELTS. THE GREATER IMPACT WITH THE SMALLER
FLAKES WILL BE THE REDUCED VISIBILITIES...ESPECIALLY IF THERE IS
ENOUGH WIND TO BLOW THE SNOW AROUND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1236 AM EST TUE JAN 5 2016
INCRSG SW WIND TNGT ABOVE LLVL INVRN ENHANCED BY NOCTURNAL COOLING
WL RESULT IN LLWS AT ALL 3 SITES THIS MRNG. WITH SOME DAYTIME
HEATING...EXPECT GUSTY SW WINDS BY LATE MRNG THRU THE AFTN. HOW
QUICKLY THIS SW FLOW TAPS MOISTER AIR WELL TO THE SW OF UPR MI IS
ANOTHER FCST CONCERN. RIGHT NOW...EXPECT VFR CONDITIONS TO PREVAIL
THRU TODAY...WITH DOWNSLOPE NATURE OF THE SW FLOW HELPING TO
MAINTAIN LOWER RH. BUT EVEN THE DRIER GUIDANCE HINTS LO CLDS WL
ARRIVE TNGT...SO FCST MVFR CIGS TO ARRIVE THIS EVNG.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 359 PM EST MON JAN 4 2016
TIGHTENING PRES GRADIENT BTWN DEPARTING HIGH PRES RIDGE AND LOW PRES
MOVING OVER HUDSON BAY WILL RESULT IN SW WINDS INCREASING TO GALES
TONIGHT ACROSS LAKE SUPERIOR. THE GALES WILL CONTINUE TUE BEFORE
WINDS BEGIN TO DIMINISH TUE NIGHT. WINDS WILL DIMINISH FURTHER
WED/THU TO MOSTLY UNDER 20KT AS A LOW PRES TROF SETTLES OVER THE
UPPER GREAT LAKES. WINDS WILL INCREASE SOME ON FRI/SAT AS LOW PRES
LIFTS NE INTO THE GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ265>267.
GALE WARNING UNTIL 10 PM EST /9 PM CST/ THIS EVENING FOR LSZ162.
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ263-264.
GALE WARNING FROM 6 AM THIS MORNING TO 1 AM EST WEDNESDAY FOR
LSZ243-244.
LAKE MICHIGAN...
GALE WARNING FROM 7 AM THIS MORNING TO 1 AM EST WEDNESDAY FOR
LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
1114 PM CST MON JAN 4 2016
.DISCUSSION...
Issued at 340 PM CST MON JAN 4 2016
Near term concerns center around the stratus deck lying under the
western half of a departing surface high. The visible and 11u-3.9u
satellite imagery revealed how thin this cloud deck was over the CWA
and as a result we saw much scattering of the deck during the
afternoon hours. Do think the stratus will reform over northwest MO
this evening. However, also expect the clearing seen over central MO
will work its way northwest overnight. The latest RAP now is in line
with the clearing shown by NAM 950mb condensation pressure deficit
progs. Overnight shift will need to monitor for potential fog
development along the periphery of the stratus.
All operational progs continue to show a rather wet period starting
as early as Wednesday morning as the first in a serious of features
work their way through the Central Plains and Mid MO River Valley.
GFS, ECMWF and SREF are in synch timing-wise with the first
shortwave, currently lifting northeast out of AZ. Warm advection
zone preceding this feature will overspread the CWA Wednesday. Have
raised PoPs. Inspection of NAM/GFS Bufr soundings continue to
support a chance of mixed precipitation. Currently the models show a
minimal warm nose aloft so either light freezing rain or snow (no
warm nose) are possible. QPF will be quite light with either one,
but enough that travel problems are possible for the morning rush
commute to work.
While a second shortwave will arrive on Thursday the increasingly
moist isentropic ascent could yield areas of drizzle/patchy rain
overnight Wednesday so high chance PoPs used. Steady moderate warm
air advection through a deep layer will allow temperatures to remain
above freezing through Friday. So, precipitation will be all liquid.
Friday night could bring a mix of rain and snow to the region as the
deformation zone lifts through the region. Quite a bit of difference
between the strength of the upper system/associated surface low with
the GFS considerably stronger. Given how much energy remains back to
the southwest within an elongated longer upper trough have little
confidence in a strong or well developed surface low. So, have not
bit on the GFS snow output.
Much colder air filters into the region over the weekend with
temperatures struggling to recover on Saturday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1111 PM CST MON JAN 4 2016
Low-level cloud cover should remain just to the west of the terminal
sites over eastern Kansas through the overnight hours underneath a
ridge axis. Winds will turn southerly by early Tuesday morning with
winds increasing into the afternoon. Mid-level clouds will enter the
area throughout the afternoon hours with sustained winds out of the
south.
&&
.EAX Watches/Warnings/Advisories...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...MJ
AVIATION...Welsh
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1122 PM CST MON JAN 4 2016
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 404 PM CST MON JAN 4 2016
THE PRIMARY FORECAST CHALLENGES WILL CENTER AROUND LOW STRATUS AND
FOG DEVELOPMENT...ALONG WITH POTENTIAL IMPACT OF CLOUDS/FOG ON
TEMPERATURES.
THIS AFTERNOON THROUGH TONIGHT...LOW STRATUS HAS BEEN SLOW TO ERODE
AND REMAINS ACROSS PORTIONS OF OUR EASTERN FORECAST AREA THIS
AFTERNOON. THESE LOW STRATUS CLOUDS ARE EXPECTED TO EXPAND BACK
ACROSS THE AREA OVERNIGHT AS MOIST SOUTHERLY WINDS KICK UP ACROSS
THE REGION. RECENT RUNS OF THE HRRR HAVE BEEN VERY AGGRESSIVE WITH
GRADUALLY DEVELOPING FOG ACROSS MUCH OF THE FORECAST AREA AS WE HEAD
THROUGH THE OVERNIGHT HOURS. THEREFORE...WILL FORECAST AREAS OF FOG
TONIGHT AND MAY EVEN END UP NEEDING A DENSE FOG HEADLINE SHOULD THE
FOG FORM AND BECOME DENSE ENOUGH. NOT ENOUGH CONFIDENCE THIS FAR OUT
TO ISSUE A HEADLINE AS OF THIS AFTERNOON...BUT WOULD NOT BE
SURPRISED IF A DENSE FOG HEADLINE IS EVENTUALLY NEEDED LATER TONIGHT.
TUESDAY...MOST FORECAST MODELS KEEP A MAJORITY OF OUR FORECAST AREA
STUCK UNDER A LOW STRATUS DECK THROUGHOUT THE DAY. SOUTHWESTERN
ZONES SEEM TO STAND THE BEST CHANCE AT CATCHING SOME LATE DAY
SUNSHINE...BUT NO GRANTEES AS THIS FOG/LOW CLOUD FORECAST IS VERY
CHALLENGING. FOG WILL BE AT ITS WORST DURING THE CLIMATOLOGICALLY
FAVORABLE TIME...TUESDAY MORNING...AND THEN SHOULD BEGIN TO LIFT
INTO MORE OF A LOW STRATUS BY LATER IN THE MORNING/AFTERNOON. THE
SOUTHERLY WINDS WILL ADVECT WARMER AIR INTO THE REGION...BUT WITH
THICK LOW CLOUDS TEMPERATURES MAY HAVE A DIFFICULT TIME RISING
MUCH...ESPECIALLY OVER SNOW COVERED AREAS. CONFIDENCE IN THE
TEMPERATURE FORECAST IS LOWER THAN NORMAL WITH A WIDE SPREAD IN
MODEL TEMPERATURES DEPENDING ON IF ANY SUN CAN POKE THROUGH THE
CLOUDS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 404 PM CST MON JAN 4 2016
THIS 6-DAY PERIOD CAN BASICALLY BE BROKEN DOWN INTO 3 TIME
FRAMES WITH THEIR OWN UNIQUE HIGHLIGHTS/CHALLENGES...AND WILL
START OUT BY BREAKING THESE DOWN:
1) TUESDAY NIGHT-WEDNESDAY NIGHT: ALTHOUGH NO ACCUMULATING SNOW IS
CURRENTLY EXPECTED DURING THESE 36 HOURS DUE TO LACK OF SATURATION
ALOFT...THERE ARE LEGITIMATE CONCERNS FOR AT LEAST SOME SPOTTY
LIGHT FREEZING DRIZZLE/FREEZING RAIN MAINLY DURING THE NIGHT AND
EARLY MORNING HOURS. THERE COULD ALSO BE MORE FOG ISSUES AS
WELL...BUT GIVEN HOW UNCERTAIN/TRICKY FOG TRENDS CAN BE IN THIS
PATTERN...AND THAT WE ALREADY HAVE FOG MENTIONED IN THE SHORT TERM
PERIOD DESCRIBED ABOVE...WILL DEFER TO LATER SHIFTS TO INTRODUCE
ANY POSSIBLE NEED FOR FOG INTO THE OFFICIAL FORECAST FOR TUESDAY
NIGHT AND BEYOND.
2) THURSDAY DAYTIME-FRIDAY NIGHT: AS HAS BEEN THE CASE FOR THE
PAST SEVERAL DAYS...THIS 48-HOUR PERIOD STILL FEATURES THE
POTENTIAL "MAIN EVENT" OF THE WEEK IN TERMS OF POTENTIAL SNOW
ACCUMULATION. ALTHOUGH WE ARE CREEPING EVER-CLOSER...BECAUSE WE
ONLY ADVERTISE OFFICIAL SNOW ACCUMULATION FORECASTS THROUGH 72
HOURS...OUR CURRENT FORECAST DOES NOT INCLUDE ANY ACCUMULATION
DATA FOR THURSDAY NIGHT-FRIDAY...WHICH IS WHEN MOST SNOW IS
EXPECTED TO FALL. THAT BEING SAID...WITH THIS POSSIBLE SNOW EVENT
WITHIN 4 DAYS NOW...AND WITH MODELS SUCH AS THE 12Z ECMWF/GFS
SUGGESTING THAT AT LEAST A FEW INCHES COULD AFFECT PARTS OF THE
CWA...HAVE OPTED TO INTRODUCE A MENTION IN OUR LATEST HAZARDOUS
WEATHER OUTLOOK (HWOGID). OF COURSE...THERE IS STILL PLENTY OF
UNCERTAINTY ESPECIALLY REGARDING THE LOW-LEVEL TEMPERATURE PROFILE
AND JUST HOW QUICKLY/SLOWLY ESPECIALLY OUR SOUTHERN/SOUTHEAST
COUNTIES WILL CHANGE OVER FROM RAIN TO SNOW...AS RAIN COULD BE THE
PREDOMINANT PRECIPITATION TYPE MUCH OF THE TIME IN THIS AREA.
CONVERSELY...ALTHOUGH SNOW APPEARS TO BE THE MORE DOMINANT TYPE IN
ESPECIALLY NORTHERN/WEST-CENTRAL COUNTIES...THERE ARE QUESTIONS
HERE ABOUT HOW MUCH PRECIPITATION MIGHT ACTUALLY FALL COMPARED TO
COUNTIES FARTHER SOUTH AND EAST. THUS...IN THEORY...THIS COULD BE
A SITUATION WHERE CENTRAL PORTIONS OF THE CWA ACTUALLY SEE THE
HIGHEST SNOWFALL AMOUNTS IF TRENDS CONTINUE ON THEIR CURRENT
TRACK...WITH LESSER AMOUNTS NORTHWEST AND SOUTHEAST. STILL TOO
SOON TO SAY FOR SURE THOUGH...AND PLEASE NOTE THAT WE ARE 24-36
HOURS AWAY FROM ADVERTISING SNOW ACCUMULATION TOTALS THAT WILL
CAPTURE THE ENTIRE EVENT.
3) SATURDAY DAYTIME-MONDAY DAYTIME: THESE LAST 3 DAYS OF THE
FORECAST HAVE BEEN KEPT AS/INTRODUCED AS OFFICIALLY DRY...AS
ALTHOUGH IT`S NOT OUT OF THE QUESTION THAT SOME VERY LIGHT
SNOW/FLURRIES COULD MAYBE LINGER INTO AT LEAST SATURDAY MORNING
IN LATER FORECASTS (ESPECIALLY PER THE ECMWF SOLUTION)...THERE
APPEARS TO BE VERY LITTLE IF ANY CHANCE OF ANOTHER LEGITIMATE
WINTRY PRECIPITATION EVENT THROUGH THIS TIME. THAT MEANS THAT THE
MAIN STORY WILL TURN TOWARD COLDER-THAN-NORMAL TEMPERATURES.
ALTHOUGH MODELS ARE CERTAINLY NOT IN LOCK-STEP AT THIS DAY 5-7
RANGE (AS IS TYPICAL)...AT LEAST FOR NOW WE ARE AIMING HIGH
TEMPERATURES ONLY INTO THE 18-28 DEGREES RANGE ACROSS MOST OF THE
CWA...WHICH IS ROUGHLY 7-15 DEGREES BELOW AVERAGE/NORMAL FOR EARLY
JANUARY. IN TURN...OVERNIGHT LOW TEMPERATURES FROM SATURDAY NIGHT
ONWARD ARE EXPECTED TO DROP INTO THE SINGLE DIGITS ABOVE ZERO
ACROSS MUCH OF THE CWA.
WITH THE PRIMARY 3 WEATHER "REGIMES" AND THEIR CONCERNS BROKEN
DOWN ABOVE...WILL FINISH WITH A FAIRLY BRIEF LOOK AT A BIT MORE
METEOROLOGICAL DETAIL IN 12-60 HOUR BLOCKS:
TUESDAY EVENING/NIGHT: ALTHOUGH PREVIOUS FORECAST ALREADY
INTRODUCED THE POSSIBILITY OF SOME LIGHT FREEZING DRIZZLE IN FAR
SOUTHEAST COUNTIES...THIS LATEST PACKAGE HAS EXPANDED THIS "SLIGHT
CHANCE" MENTION OF FREEZING DRIZZLE AND/OR DRIZZLE TO ENCOMPASS
THE MAJORITY OF THE CWA...ASSUMING OF COURSE THAT WIDESPREAD LOW
STRATUS CLOUDS DO IN FACT DOMINATE THE AREA IN INCREASINGLY-MOIST
LOW LEVEL SOUTHERLY FLOW. VARIOUS 12Z/18Z MODELS ARE IN GOOD
AGREEMENT IN TRACKING THE FIRST LEGITIMATE-BUT-LOW-AMPLITUDE MID
LEVEL SHORTWAVE TROUGH OF THE WEEK NORTHEASTWARD ACROSS THE HEART
OF NEB/KS...THUS PROVIDING AT LEAST LOW-LEVEL LIFT FOR SOME
DRIZZLY ACTIVITY. THERE ARE HINTS THAT MAINLY THE FAR SOUTHEAST
CWA COULD SEE A QUICK BURST OF SNOW/POSSIBLY SLEET...BUT THIS
SEEMS MORE FAVORED OUTSIDE THE CWA WITHIN EASTERN KS. ASSUMING
PLENTIFUL CLOUDS AND SOUTHERLY SURFACE BREEZES GENERALLY 10-15
MPH...THIS SHOULD BE A SEASONABLY "MILD" NIGHT WITH LOWS ONLY
DROPPING TO AROUND 30 MOST PLACES.
WEDNESDAY/WEDNESDAY NIGHT: WHILE THE LOCAL AREA LARGELY SITS "IN
BETWEEN" UPPER LEVEL WAVES/FORCING DURING THIS TIME...THE PESKY
LOW-LEVEL STRATUS/SATURATION LOOKS TO PERSIST...AND THUS HAVE KEPT
A MENTION OF LIGHT RAIN/FREEZING RAIN OR LIGHT DRIZZLE/FREEZING
DRIZZLE GOING MUCH OF THIS TIME...DEPENDING ON SURFACE TEMPS.
SPEAKING OF WHICH...CONFIDENCE IS BELOW AVERAGE REGARDING WED HIGH
TEMPS DEPENDING ON THE BATTLE OF SOUTHERLY WARM AIR ADVECTION
VERSUS CLOUD COVER...BUT IF ANYTHING NUDGED HIGHS DOWN 1-2 DEGREES
FROM PREVIOUS WITH MID-UPPER 30S IN MOST NEB ZONES.
THURSDAY-THURSDAY NIGHT: SEE NUMBER "2" ABOVE FOR VARIOUS COMMENTS
ON THIS POSSIBLE SNOW EVENT...BUT IT WOULD GET UNDERWAY DURING
THIS TIME FRAME AS THE NEXT BATCH OF MID-UPPER FORCING ARRIVES
FROM THE SOUTHWEST...ALTHOUGH NOT IN AN OVERLY-ORGANIZED FASHION.
LATER FORECASTS MAY HAVE TO CONSIDER EXTENDING DRIZZLE/FREEZING
DRIZZLE POTENTIAL INTO AT LEAST THURSDAY DAYTIME BEFORE STEADIER
SNOW AND/OR RAIN BECOMES THE MORE DOMINANT TYPE. HAVE LOW END
"LIKELY" 60 PERCENT PRECIP CHANCES ACROSS MOST OF THE CWA FOR
THURSDAY NIGHT.
FRIDAY-FRIDAY NIGHT: ALTHOUGH ITS POSSIBLE THAT A LITTLE RAIN
POTENTIAL COULD STILL BE PRESENT BY SUNRISE FRIDAY IN FAR
SOUTHEAST ZONES...DEEPENING COLD AIR BEHIND A PASSING SURFACE COLD
FRONT SHOULD TRANSITION PRECIP TYPE TO SNOW ACROSS THE ENTIRE AREA
IF IT HASN`T ALREADY. WHILE SOME MODELS SUCH AS THE GFS PRETTY
MUCH SHUT DOWN ACCUMULATING SNOW BY FRIDAY NIGHT...OTHERS SUCH AS
THE ECMWF KEEP IT GOING.
SATURDAY DAYTIME-MONDAY DAYTIME: NOTHING MORE TO SAY HERE OTHER
THAN WHAT WAS ALREADY COVERED IN NUMBER "3" EARLIER ON: CONFIDENCE
IS REASONABLY HIGH IN A MAINLY SNOW-FREE STRETCH OF WEATHER WITH
THE ONLY REAL QUESTION SURROUNDING HOW COLD IT ACTUALLY GETS.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1118 PM CST MON JAN 4 2016
LOW CLOUDS HAVE ALREADY MOVED INTO THE TERMINALS AND EXPECT THE
IFR CEILINGS TO CONTINUE THROUGH THE NIGHT AND INTO THE MORNING
HOURS. VISIBILITIES WILL DROP TO MVFR LATER TONIGHT AND INTO THE
MORNING. CEILINGS WILL LIFT A LITTLE DURING THE DAY TIME...BUT
ARE EXPECTED TO DROP BACK AGAIN AFTER DARK.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...WESELY
LONG TERM...PFANNKUCH
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS PORTLAND OR
944 PM PST MON JAN 4 2016
.SYNOPSIS...AN UPPER LEVEL LOW PRESSURE SYSTEM OFF THE COAST WILL
CONTINUE TO SEND A SERIES OF WEAK DISTURBANCES N THROUGH WESTERN
OREGON AND WASHINGTON THROUGH TUE NIGHT. A CHILLY AIR MASS WILL
REMAIN IN PLACE...REINFORCED BY E WINDS BLOWING THROUGH THE GORGE.
THIS WILL KEEP A CHANCE OF RAIN IN THE FORECAST FOR THE NEXT COUPLE
OF DAYS...ALONG WITH THE POSSIBILITY OF SOME FREEZING RAIN ESPECIALLY
IN AND AROUND THE GORGE. THE LOW WILL HEAD TOWARDS NORTHERN CA LATER
IN THE WEEK...LEAVING THE REGION WITH DWINDLING CHANCES FOR RAIN BUT
WITH COOL TEMPERATURES CONTINUING.
&&
.EVENING UPDATE...LATEST NWS DOPPLER RADAR IMAGERY SHOWS SOME WEAK
ECHOES OVER SW WASHINGTON AND NW OREGON THIS EVENING AS MID LEVEL
MOISTURE CONTINUES TO STREAM IN AHEAD OF LOW PRES OFFSHORE TO OUR
SOUTHWEST. OCCASIONAL LIGHT PRECIPITATION IS EXPECTED TO REACH THE
GROUND OVER THE NEXT FEW HOURS. MEANWHILE A MORE ORGANIZED AREA OF
PRECIPITATION IS MOVING ONTO THE N CALIF AND S OREGON COAST AHEAD OF
THE MAIN UPPER LEVEL TROUGH AND OCCLUDED LOW LEVEL FRONTAL BOUNDARY.
THE LATEST RUNS OF THE HRRR MODEL INDICATE A BIT STEADIER
PRECIPITATION TO DEVELOP OVER THE SOUTHERN PORTIONS OF THE FCST AREA
AFTER MIDNIGHT...THEN LIFT NORTHWARD OVERNIGHT INTO TUE AM.
HOWEVER...QPF TOTALS STILL LOOK TO BE QUITE LIGHT. LOOKING AT THE
OBSERVED TEMPERATURE TRENDS OF THE PAST FEW HOURS...DECIDED TO ISSUE
A FREEZING RAIN ADVISORY FOR MOST OF THE INTERIOR LOWLANDS AND FOR
THE COAST RANGE AND CASCADE FOOTHILLS. THERE ARE NUMEROUS LOCATIONS
THAT ARE NOW HOVERING RIGHT AT FREEZING. DEW POINTS OVER MUCH OF THE
REGION SIT AROUND 30 TO 32 DEG AND THERE IS CONSIDERABLE MID LEVEL
CLOUD COVER OVER THE REGION...SO DO NOT THINK WE WILL SEE TEMPS COOL
MUCH MORE AT THIS POINT. WIDESPREAD ICE ACCUMULATIONS ARE NOT
EXPECTED...BUT IT APPEARS THAT THERE IS POTENTIAL FOR LOCALIZED SPOTS
TO SEE AN ADDITIONAL GLAZING OF ICE GOING INTO THE TUE AM COMMUTE.
THE BEST CHANCES FOR THIS TO OCCUR ARE AROUND THE GORGE WHERE THE
COLD EASTERLY FLOW CONTINUES TO POUR THROUGH...AND POTENTIALLY IN THE
HIGHER TERRAIN AROUND THE PORTLAND METRO AREA. TEMPERATURES LOOK TO
WARM ABOVE FREEZING BY LATER TOMORROW MORNING FOR MOST OF THE
REGION...CONFINING ANY ADDITIONAL FROZEN PRECIPITATION THREAT TO THE
GORGE AREA AND THE CASCADES. PYLE
.PREVIOUS SHORT TERM DISCUSSION UNCHANGED...
TEMPERATURES THROUGH MOST OF THE WILLAMETTE VALLEY HAD WARMED ABOVE
FREEZING EARLY MON AFTERNOON...ALTHOUGH MESOWEST PLOTS SHOWED A FEW
POCKETS OF SUB FREEZING TEMPS...INCLUDING THE S END OF THE VALLEY
WHERE FOG AND LOW CLOUDS REMAINED. COLDER AIR REMAINED IN THE GORGE
AND HOOD RIVER VALLEY. AN OFFSHORE FLOW CONTINUED THROUGH THE GORGE
WHERE THE PDX TO DLS SURFACE PRES GRADIENT WAS STILL CLOSE TO 7 MB. A
COUPLE OF WEAK SHORTWAVES WERE EXPECTED TO MOVE N OVERNIGHT BRINGING
RENEWED THREATS OF PRECIPITATION...AS THE MAIN UPPER TROUGH REMAINS
OFFSHORE BETWEEN 130W AND 140W. A SLIGHTLY BETTER THREAT FOR
PRECIPITATION COMES TUE AS A SOUTHERLY H8 FLOW INCREASES MOISTURE
TRANSPORT AND ANOTHER SHORT WAVE LIFTS N. PRECIPITATION ASSOCIATED
WITH THE SHORTWAVES TONIGHT IS GENERALLY EXPECTED TO BE LIGHT WITH
MAIN MOISTURE CONFINED TO MID AND UPPER LEVELS. IN GENERAL WILL BRING
POPS BACK TO LIKELY CATEGORY MOST AREAS TONIGHT...WITH THE GREATER
THREAT COMING WITH THE SECOND SHORTWAVE LATE TONIGHT. THE AREAL
EXTENT OF SUB FREEZING TEMPS LATER TONIGHT INTO TUE MORNING IS NOT
CLEAR. MOS GUIDANCE AND MODELS IN GENERAL APPEAR TOO QUICK TO WARM
AND KEEP WARM THE SURFACE TEMPS. WILL TEND TO THE COLDER SIDE OF
GUIDANCE SURFACE TEMPS TONIGHT INTO TUE...WHICH COUPLED WITH CURRENT
TEMPS SUGGESTS THE NEED TO INCLUDE SOME CHANCE FOR FREEZING RAIN
THROUGHOUT THE WILLAMETTE VALLEY AND INTO THE COAST RANGE FOOTHILLS
TONIGHT. MAIN THREAT HOWEVER WILL REMAIN IN AND NEAR THE WESTERN
GORGE. WILL HOLD OFF ON ANY WINTER WEATHER ADVISORIES AT THIS
POINT...BUT SUSPECT SOME MAY BE NEEDED LATER TONIGHT AS FREEZING RAIN
BECOMES MORE IMMINENT TO SOME LOCATIONS. IN THE CENTRAL GORGE AND
HOOD RIVER VALLEY COLD AIR MASS REMAINS SUFFICIENTLY DEEP TO MAKE THE
PRIMARY THREAT SNOW. POPS HOWEVER WILL BE KEPT IN CHANCE CATEGORY
THERE.
MODELS IN GENERAL DIGGING THE UPPER LOW SE...HEADED TOWARDS NORTHERN
CA LATE IN THE WEEK. WITH THE BULK OF THE ENERGY HEADED S OF THE
FORECAST AREA...THE FOCUS FOR PRECIPITATION WILL ALSO SHIFT FURTHER
S. WILL TAPER OFF THE CHANCES FOR RAIN IN THE BEGINNING WED...BUT
HOLD ON TO SLIGHT CHANCE POPS THROUGH THU IN THE S.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...THE MODELS ARE BUILDING
ANOTHER UPPER RIDGE ALONG THE PACIFIC NORTHWEST COAST EARLY IN THE
PERIOD THAT APPEARS IT WILL HANG ON UNTIL EARLY NEXT WEEK. ANY
INITIAL SYSTEMS LOOK TO SPLIT AND GO SOUTH OF OUR FORECAST AREA. WE
WILL CONTINUE TO HAVE TO DEAL WITH OUR PERSISTENT OFFSHORE FLOW
THROUGH THE GORGE...KEEPING TEMPS ON THE COOL SIDE. THE MODELS...
ESPECIALLY THE ECMWF AND GEM...SHOW SOME POSSIBILITIES OF
PRECIPITATION EARLY NEXT WEEK...AND HAVE SOME LOW POPS IN THE
FORECAST FOR THIS. THE GORGE WILL LIKELY BE DEALING WITH WINTER
PRECIPITATION...AND POSSIBLY IN THE NORTH INTERIOR AS WELL. TOLLESON
&&
.AVIATION...A PAIR OF DISTURBANCES WILL MOVE NORTH ACROSS THE
FORECAST AREA TONIGHT...AND AGAIN LATE TUESDAY. THE MAIN CONCERN
FOR THE UPCOMING TAF PACKAGE WILL CONTINUE TO BE THE PRECIP TYPE
IN THE NORTHERN INTERIOR AND FOG/LOW STRATUS FURTHER SOUTH. IN THE
NORTH...TEMPS LOOK TO HOVER RIGHT AROUND FREEZING ALL NIGHT.
SUSPECT WE WILL SEE SOME -RA WITH THE INITIAL SURGE OF PRECIP
TONIGHT...WITH THINGS POSSIBLY SWITCHING OVER TO -FZRA AFTER 08Z.
THE SOUTH VALLEY HAS STRUGGLED TO GET RID OF ITS LOWER
CLOUDS...SO SUSPECT LOWER CIGS WILL PERSIST AT KEUG AND LIKELY
REDEVELOP NEAR KSLE OVERNIGHT. IN ADDITION...PRECIP FURTHER SOUTH
LOOKS TO REMAIN -RA.
CONDITIONS ACROSS THE FORECAST AREA GENERALLY VFR...WITH POCKETS
OF MVFR VSBY AND IFR/LIFR CIGS. EXPECT CONDITIONS TO DETERIORATE
TOWARDS AT LEAST MVFR TONIGHT BEHIND THE INITIAL SURGE OF
MOISTURE. CONDITIONS LOOK TO IMPROVE TOWARDS VFR TUESDAY
AFTERNOON...BUT WILL LIKELY LOWER LATE TUESDAY WITH THE SECOND
SYSTEM. THE EXCEPTION WILL BE KHIO...KSLE...AND KEUG WHICH LOOK
TO REMAIN IFR. THE GOOD NEWS FOR THE TAFS IS THAT TEMPS TUESDAY
NIGHT LOOK TO REMAIN ABOVE FREEZING SO -FZRA CONCERNS WILL BE
MINIMAL.
KPDX AND APPROACHES...EXPECT MOSTLY VFR CONDITIONS AND ABOVE
FREEZING TEMPS THROUGH AROUND 08Z. INITIAL SURGE OF MOISTURE
TONIGHT WILL LOWER CIGS TOWARDS MVFR...WITH PRECIP POSSIBLY
SWITCHING TO -FZRA. CONDITIONS LOOK TO IMPROVE TOWARDS VFR TUESDAY
AFTERNOON. WILL LIKELY SEE -RA AND LOWER CIGS DEVELOP LATE
TUESDAY. /64
&&
.MARINE...EAST TO SOUTHEAST WINDS OVER THE WATERS GENERALLY
AROUND 15 KT WITH OCCASIONAL GUSTS TO NEAR 20 KT. SOUTHEAST WINDS
WILL INCREASE TONIGHT AHEAD OF THE NEXT LOW PRES SYSTEM BRINGING
GUSTS TO 30 KT AFTER MIDNIGHT. AS THE LOW APPROACHES THE OUTER
WATERS TUESDAY WINDS LOOK TO INCREASE FURTHER...WITH GUSTS TO 40
KT LIKELY DEVELOPING TUESDAY AFTERNOON. HOWEVER...00Z MODEL RUNS
HAVE PUSHED BACK THE TIMING OF THE STRONGEST GUSTS A FEW HOURS
AND THERE REMAINS SOME UNCERTAINTY WITH THE STRENGTH AND TRACK OF
THE LOW. WILL KEEP THE SMALL CRAFT ADVISORY FOR WINDS AND THE GALE
WATCH AS IS TO ALLOW FUTURE MODEL RUNS TO COME IN.
SEAS CONTINUE TO HOVER AROUND 7 TO 9 FT THIS EVENING WITH A
COMBINATION OF WEST AND SOUTH SWELLS AND EAST WIND WAVES CREATING
CONFUSED SEAS. A SERIES OF STRONG STORM SYSTEMS SOUTH OF THE
ALEUTIANS WILL BUILD A LONG PERIOD SWELL THAT WILL ARRIVE LATE
TONIGHT. SEAS WILL BUILD TOWARDS 11 FT AFTER MIDNIGHT AND PEAK
NEAR 17 FT TUESDAY AFTERNOON SO WILL KEEP THE SMALL CRAFT ADVISORY
FOR SEAS AS IS. THERE IS ALSO A CHANCE THAT WE MAY SEE SOME HIGH
SURF CONDITIONS ON THE NW OREGON COAST TUESDAY...BUT CONFIDENCE IS
LOW AND CONDITIONS REMAIN MARGINAL SO WILL HOLD OFF ON ISSUING A
HIGH SURF ADVISORY. SEAS LIKELY REMAIN ELEVATED THROUGH THE END OF
THE WEEK. /64
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FROM TUESDAY MORNING THROUGH WEDNESDAY MORNING 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 WINDS FROM MIDNIGHT TONIGHT TO 10 AM
PST TUESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM MIDNIGHT TONIGHT
TO 10 AM PST TUESDAY FOR COASTAL WATERS FROM CAPE
SHOALWATER WA TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 10 PM
THIS EVENING TO 2 AM PST TUESDAY.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 9 AM
TO 9 PM PST TUESDAY.
&&
$$
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 PHOENIX AZ
900 AM MST TUE JAN 5 2016
.SYNOPSIS...
ANTICIPATE SCATTERED SHOWERS THIS MORNING BEFORE MORE NUMEROUS
SHOWERS DEVELOP LATER TODAY. WITH THE NEXT WEATHER SYSTEM IN THE
SERIES. PRECIPITATION CHANCES CONTINUE THROUGH FRIDAY. BELOW NORMAL
HIGH TEMPERATURES WILL CONTINUE AS WELL. CONDITIONS WILL START TO
DRY OUT FOR THE COMING WEEKEND...BUT TEMPERATURES WILL REMAIN BELOW
SEASONAL NORMALS.
&&
.DISCUSSION...
NOT A WHOLE LOT OF RAIN ACROSS THE AREA AT THE MOMENT BUT LINGERING
MOISTURE RESULTED IN QUITE A BIT OF LOW CLOUDS AND EVEN SOME FOG
ACROSS PARTS OF THE AREA /MAINLY SOUTHWEST ARIZONA AND SOUTHEAST
CALIFORNIA/. WITH HIGH CLOUDS APPROACHING FROM THE WEST...FOG HAS
DISSIPATED ACROSS THESE AREAS AND THE DENSE FOG ADVISORY HAS BEEN
ALLOWED TO EXPIRE.
A QUICK LOOK AT THE AVAILABLE 12Z MODELS AND 09Z SREF INDICATES MOST
OF THE DAY SHOULD BE DRY ACROSS THE LOWER DESERTS...ONLY TO BE
REPLACED BY SHOWERS LATE THIS AFTERNOON/EVENING AS THE SECOND OF FOUR
TROUGHS APPROACHES THE AREA. OPERATIONAL MODELS AND ENSEMBLES STILL
POINTING TOWARD SHOWERS DEVELOPING ACROSS EL CENTRO/BLYTHE/YUMA
AROUND 00Z AND IN THE PHOENIX AREA CLOSER TO 06Z. HRRR RUNS ARE ALSO
INDICATING SIMILAR TIMING. IF ANYTHING THIS MAY BE TRENDING SLIGHTLY
FASTER THAN PREVIOUS RUNS INDICATED AND THE PREVIOUS SHIFTS CORRECTLY
ACCOUNTED FOR THIS. ONLY MAKING MINOR ADJUSTMENTS TO THE INHERITED
POPS AND WX GRIDS BASED ON OBSERVATIONAL TRENDS. OTHERWISE THE
FORECAST IS IN GOOD SHAPE.
&&
.PREVIOUS DISCUSSION...
TODAY THROUGH FRIDAY...
THE NEXT SYSTEM IS ALREADY MOVING INTO CALIFORNIA. LIFTING
MECHANISMS WITH THIS SYSTEM LOOK TO BE SIMILAR TO MONDAYS WITH SOME
LOWER LEVEL CONVERGENCE...UPPER LEVEL DIVERGENCE...AND A DIV Q
BULLSEYE. NAM NOT AS ROBUST AS THE GFS IS IN THOSE FIELDS. LATEST
MODELS INDICATE ITS ARRIVAL AND DEPARTURE WILL BE A BIT FASTER THAN
WAS DEPICTED IN PREVIOUS FORECAST PACKAGE. MADE ADJUSTMENTS TO THE
POPS ACCORDINGLY. SREF INDICATES SOME VERY MODEST CAPE FOR TODAY AND
TONIGHT. SPC HAS GENERAL THUNDER IN THE DAY 1 OUTLOOK FOR OUR WESTERN
AREAS...THOUGH SREF CAPE IS A BIT EAST OF THERE. TAKING THESE FACTORS
INTO ACCOUNT ALONG WITH MODEL LIFTED INDICES...ADDED SLIGHT CHANCE OF
THUNDERSTORMS FOR THIS AFTERNOON AND EVENING. OVERALL...QPF IS
LOOKING HIGHER WITH THIS SYSTEM THAN WHAT WE HAD WITH MONDAYS.
ADVISORY TYPE IMPACTS ARE QUITE POSSIBLE. SNOW LEVELS GENERALLY
REMAIN NEAR OR ABOVE 6000 FEET.
NEXT SYSTEM HAS TWO MAIN WAVES WITH IT. THE FIRST ONE MOVES IN WEDNESDAY
NIGHT AND EXITS OUR EASTERN AREAS THURSDAY EVENING. THE SECOND ONE IS
RIGHT ON ITS HEELS FOR FRIDAY. THE SECOND ONE HAS LESS LIFT GOING FOR
IT. SNOW LEVELS DROP THURSDAY AND FRIDAY...DOWN TO ABOUT 4000-4500 FEET
FRIDAY MORNING AND NOT CHANGING MUCH DURING THE DAY FRIDAY.
ADDITIONAL PRECIP FOR REST OF THIS WEEK...IS 1.5-2.5 INCHES OVER THE
FOOTHILLS AND HIGHER TERRAIN...1.0-1.5 INCHES OVER THE PHOENIX
AREA...AND 0.25-0.75 OVER SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.
SATURDAY THROUGH MONDAY...
NORTHWEST FLOW AND WEAK DRY ADVECTION ACROSS THE AREA LOOKS LIKELY
THROUGH THE WEEKEND INTO NEXT WEEK...ALTHOUGH THERE`S SOME HINT AT A
DRY TROUGH MOVING THROUGH THE AREA ON SUNDAY /SOME INCREASED CLOUD
COVER AND THAT`S ABOUT IT/. SHOULD THIS TROUGH NOT DEVELOP...WE`LL NEED
TO KEEP AN EYE ON FOG POTENTIAL THIS WEEKEND /SATURDAY OR SUNDAY/ IF
THE BL DOESN`T SUFFICIENTLY DRY OUT. THE PATTERN IS CERTAINLY
CONDUCIVE FOR WIDESPREAD FOG DEVELOPMENT ACROSS THE AREA AND IT
WARRANTS MENTIONING. FAIRLY GOOD AGREEMENT OF STRONG UPPER RIDGING
ACROSS THE AREA BY MONDAY OF NEXT WEEK WITH TEMPERATURES RETURNING TO
EARLY JANUARY NORMALS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
DESPITE WEAK AND FLAT UPPER RIDGING NOW MOVING INTO THE
DESERTS...CONSIDERABLE LOW LEVEL MOISTURE REMAINS IN PLACE AND THERE
WILL BE LINGERING ISOLD/SCT LIGHT SHOWERS THROUGH MID MORNING WITH
WIDESPREAD CIGS BELOW 5K FEET...WITH SCATTERED CIGS TO AROUND 2K
FEET THRU 16Z OR SO. AFTER THAT CIGS SHOULD GENLY STAY IN THE 4-6K
BALLPARK WITH FEW-SCT LOWER DECKS AT TIMES. ANOTHER WET WEATHER
SYSTEM WILL MOVE IN FROM THE WEST TONIGHT LEADING TO WIDESPREAD
SHOWERS STARTING BY AROUND 03Z...CAUSING AREAS OF CIGS DOWN TO 2K
FEET WITH THE POTENTIAL FOR SOME VSBY RESTRICTIONS BELOW 5SM IN
FOG/MIST OR EVEN MODERATE TO HEAVY RAIN. WINDS AGAIN WILL FAVOR THE
EAST TO SOUTHEAST FOR THE NEXT 24 HOURS AT THE TAF SITES.
FINALLY...WE CANNOT RULE OUT AN ISOLATE THUNDERSTORM DEVELOPING
TONIGHT AS THE SYSTEM PASSES THROUGH BUT CONFIDENCE WAY TOO LOW TO
MENTION THUNDER IN ANY OF THE TAFS AT THIS TIME.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THE THREAT FOR PRECIP THIS MORNING IS FAIRLY LOW BUT CONSIDERABLE
LOW CLOUDS WILL REMAIN IN PLACE WITH WIDESPREAD CIGS 4-6 FEET
EXPECTED ALONG WITH THE OCCASIONAL CIG DOWN TO 3K FEET OR LOWER SUCH
AS AT KBLH. THEN...ANOTHER WET PACIFIC LOW WILL MOVE INTO THE AREA
FROM THE WEST THIS AFTERNOON LEADING TO SCATTERED TO NUMEROUS
LIGHT/MODERATE SHOWERS AND A RETURN TO VERY LOW CIGS ALONG WITH SOME
VSBY RESTRICTIONS. SHOWERS WILL DISSIPATE WITH PARTIAL CLEARING FROM
THE WEST STARTING BY AROUND 03Z WITH MAINLY SCATTERED DECKS EXPECTED
AFTER MIDNIGHT. EXPECT MAINLY LIGHT VARIABLE TO SOUTHEAST WINDS
TODAY BECOMING A BIT STRONGER FROM THE SOUTHWEST TO WEST OVERNIGHT
TONIGHT.
FINALLY...WE CANNOT RULE OUT AN ISOLATED THUNDERSTORM MIXED IN
MAINLY DURING THE AFTERNOON HOURS BUT CONFIDENCE IS TOO LOW TO
MENTION IN THE TAFS AT THIS TIME.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER... THURSDAY THROUGH MONDAY...A COUPLE MORE WEATHER
DISTURBANCES WILL MOVE THROUGH THE DISTRICTS IN CLOSE SUCCESSION
DURING THE LATTER HALF OF THE WORK WEEK...MAINLY EAST OF THE LOWER
COLORADO RIVER VALLEY. RAIN CHANCES TAPER OFF FOR THE WEEKEND AND
INTO EARLY NEXT WEEK. HUMIDITY WILL BE MUCH ABOVE AVERAGE WITH
MINIMUM VALUES NEAR AND ABOVE 50 PERCENT MOST DAYS ON THE LOWER
DESERTS AND MAX VALUES NEAR AND ABOVE 80 PERCENT MUCH OF THE TIME.
VALUES TREND DOWN FROM WEST TO EAST SATURDAY INTO MONDAY BUT
GENERALLY REMAIN ABOVE 30 PERCENT MOST PLACES. EXPECT WELL BELOW
NORMAL HIGH TEMPERATURES THROUGH FRIDAY WITH DESERT HIGHS IN THE
50S...AND SLIGHT WARMING OVER THE WEEKEND AS HUMIDITIES START TO
FALL OFF. DESPITE THE ACTIVE WEATHER PATTERN NO STRONG WIND EVENTS
ARE EXPECTED BUT JUST BREEZY AT TIMES...MAINLY ON THURSDAY.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...LEINS/AJ
AVIATION...CB
FIRE WEATHER...AJ/CB
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
550 AM MST TUE JAN 5 2016
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.
&&
.SYNOPSIS...
ANTICIPATE SCATTERED SHOWERS THIS MORNING BEFORE MORE NUMEROUS
SHOWERS DEVELOP LATER TODAY. WITH THE NEXT WEATHER SYSTEM IN THE
SERIES. PRECIPITATION CHANCES CONTINUE THROUGH FRIDAY. BELOW NORMAL
HIGH TEMPERATURES WILL CONTINUE AS WELL. CONDITIONS WILL START TO
DRY OUT FOR THE COMING WEEKEND...BUT TEMPERATURES WILL REMAIN BELOW
SEASONAL NORMALS.
&&
.DISCUSSION...
TODAY THROUGH FRIDAY...
BAND OF PRECIP THAT BROUGHT MUCH OF YESTERDAYS RAINFALL TO SOUTH-
CENTRAL ARIZONA HAS BEEN SLOWLY DISSIPATING. HOWEVER...A TRAILING
IMPULSE IS KEEPING SOME ISOLATED VERY LIGHT SHOWERS GOING. HRRR KEEPS
THESE GOING AND EXPANDS THE AREA TO THE LOWER COLORADO RIVER VALLEY
BEFORE SUNRISE. THE NEXT SYSTEM IS ALREADY MOVING INTO CALIFORNIA.
LIFTING MECHANISMS WITH THIS SYSTEM LOOK TO BE SIMILAR TO MONDAYS
WITH SOME LOWER LEVEL CONVERGENCE...UPPER LEVEL DIVERGENCE...AND A
DIV Q BULLSEYE. NAM NOT AS ROBUST AS THE GFS IS IN THOSE FIELDS.
LATEST MODELS INDICATE ITS ARRIVAL AND DEPARTURE WILL BE A BIT FASTER
THAN WAS DEPICTED IN PREVIOUS FORECAST PACKAGE. MADE ADJUSTMENTS TO
THE POPS ACCORDINGLY. SREF INDICATES SOME VERY MODEST CAPE FOR TODAY
AND TONIGHT. SPC HAS GENERAL THUNDER IN THE DAY 1 OUTLOOK FOR OUR
WESTERN AREAS...THOUGH SREF CAPE IS A BIT EAST OF THERE. TAKING THESE
FACTORS INTO ACCOUNT ALONG WITH MODEL LIFTED INDICES...ADDED SLIGHT
CHANCE OF THUNDERSTORMS FOR THIS AFTERNOON AND EVENING. OVERALL...QPF
IS LOOKING HIGHER WITH THIS SYSTEM THAN WHAT WE HAD WITH MONDAYS.
ADVISORY TYPE IMPACTS ARE QUITE POSSIBLE. SNOW LEVELS GENERALLY
REMAIN NEAR OR ABOVE 6000 FEET.
NEXT SYSTEM HAS TWO MAIN WAVES WITH IT. THE FIRST ONE MOVES IN WEDNESDAY
NIGHT AND EXITS OUR EASTERN AREAS THURSDAY EVENING. THE SECOND ONE IS
RIGHT ON ITS HEELS FOR FRIDAY. THE SECOND ONE HAS LESS LIFT GOING FOR
IT. SNOW LEVELS DROP THURSDAY AND FRIDAY...DOWN TO ABOUT 4000-4500 FEET
FRIDAY MORNING AND NOT CHANGING MUCH DURING THE DAY FRIDAY.
ADDITIONAL PRECIP FOR REST OF THIS WEEK...IS 1.5-2.5 INCHES OVER THE
FOOTHILLS AND HIGHER TERRAIN...1.0-1.5 INCHES OVER THE PHOENIX
AREA...AND 0.25-0.75 OVER SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.
SATURDAY THROUGH MONDAY...
NORTHWEST FLOW AND WEAK DRY ADVECTION ACROSS THE AREA LOOKS LIKELY
THROUGH THE WEEKEND INTO NEXT WEEK...ALTHOUGH THERE`S SOME HINT AT A
DRY TROUGH MOVING THROUGH THE AREA ON SUNDAY /SOME INCREASED CLOUD
COVER AND THAT`S ABOUT IT/. SHOULD THIS TROUGH NOT DEVELOP...WE`LL NEED
TO KEEP AN EYE ON FOG POTENTIAL THIS WEEKEND /SATURDAY OR SUNDAY/ IF
THE BL DOESN`T SUFFICIENTLY DRY OUT. THE PATTERN IS CERTAINLY
CONDUCIVE FOR WIDESPREAD FOG DEVELOPMENT ACROSS THE AREA AND IT
WARRANTS MENTIONING. FAIRLY GOOD AGREEMENT OF STRONG UPPER RIDGING
ACROSS THE AREA BY MONDAY OF NEXT WEEK WITH TEMPERATURES RETURNING TO
EARLY JANUARY NORMALS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
DESPITE WEAK AND FLAT UPPER RIDGING NOW MOVING INTO THE
DESERTS...CONSIDERABLE LOW LEVEL MOISTURE REMAINS IN PLACE AND THERE
WILL BE LINGERING ISOLD/SCT LIGHT SHOWERS THROUGH MID MORNING WITH
WIDESPREAD CIGS BELOW 5K FEET...WITH SCATTERED CIGS TO AROUND 2K
FEET THRU 16Z OR SO. AFTER THAT CIGS SHOULD GENLY STAY IN THE 4-6K
BALLPARK WITH FEW-SCT LOWER DECKS AT TIMES. ANOTHER WET WEATHER
SYSTEM WILL MOVE IN FROM THE WEST TONIGHT LEADING TO WIDESPREAD
SHOWERS STARTING BY AROUND 03Z...CAUSING AREAS OF CIGS DOWN TO 2K
FEET WITH THE POTENTIAL FOR SOME VSBY RESTRICTIONS BELOW 5SM IN
FOG/MIST OR EVEN MODERATE TO HEAVY RAIN. WINDS AGAIN WILL FAVOR THE
EAST TO SOUTHEAST FOR THE NEXT 24 HOURS AT THE TAF SITES.
FINALLY...WE CANNOT RULE OUT AN ISOLATE THUNDERSTORM DEVELOPING
TONIGHT AS THE SYSTEM PASSES THROUGH BUT CONFIDENCE WAY TOO LOW TO
MENTION THUNDER IN ANY OF THE TAFS AT THIS TIME.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
THE THREAT FOR PRECIP THIS MORNING IS FAIRLY LOW BUT CONSIDERABLE
LOW CLOUDS WILL REMAIN IN PLACE WITH WIDESPREAD CIGS 4-6 FEET
EXPECTED ALONG WITH THE OCCASIONAL CIG DOWN TO 3K FEET OR LOWER SUCH
AS AT KBLH. THEN...ANOTHER WET PACIFIC LOW WILL MOVE INTO THE AREA
FROM THE WEST THIS AFTERNOON LEADING TO SCATTERED TO NUMEROUS
LIGHT/MODERATE SHOWERS AND A RETURN TO VERY LOW CIGS ALONG WITH SOME
VSBY RESTRICTIONS. SHOWERS WILL DISSIPATE WITH PARTIAL CLEARING FROM
THE WEST STARTING BY AROUND 03Z WITH MAINLY SCATTERED DECKS EXPECTED
AFTER MIDNIGHT. EXPECT MAINLY LIGHT VARIABLE TO SOUTHEAST WINDS
TODAY BECOMING A BIT STRONGER FROM THE SOUTHWEST TO WEST OVERNIGHT
TONIGHT.
FINALLY...WE CANNOT RULE OUT AN ISOLATED THUNDERSTORM MIXED IN
MAINLY DURING THE AFTERNOON HOURS BUT CONFIDENCE IS TOO LOW TO
MENTION IN THE TAFS AT THIS TIME.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER... THURSDAY THROUGH MONDAY...A COUPLE MORE WEATHER
DISTURBANCES WILL MOVE THROUGH THE DISTRICTS IN CLOSE SUCCESSION
DURING THE LATTER HALF OF THE WORK WEEK...MAINLY EAST OF THE LOWER
COLORADO RIVER VALLEY. RAIN CHANCES TAPER OFF FOR THE WEEKEND AND
INTO EARLY NEXT WEEK. HUMIDITY WILL BE MUCH ABOVE AVERAGE WITH
MINIMUM VALUES NEAR AND ABOVE 50 PERCENT MOST DAYS ON THE LOWER
DESERTS AND MAX VALUES NEAR AND ABOVE 80 PERCENT MUCH OF THE TIME.
VALUES TREND DOWN FROM WEST TO EAST SATURDAY INTO MONDAY BUT
GENERALLY REMAIN ABOVE 30 PERCENT MOST PLACES. EXPECT WELL BELOW
NORMAL HIGH TEMPERATURES THROUGH FRIDAY WITH DESERT HIGHS IN THE
50S...AND SLIGHT WARMING OVER THE WEEKEND AS HUMIDITIES START TO
FALL OFF. DESPITE THE ACTIVE WEATHER PATTERN NO STRONG WIND EVENTS
ARE EXPECTED BUT JUST BREEZY AT TIMES...MAINLY ON THURSDAY.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ/LEINS
AVIATION...CB
FIRE WEATHER...AJ/CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
343 AM MST TUE JAN 5 2016
.SYNOPSIS...
ANTICIPATE SCATTERED SHOWERS THIS MORNING BEFORE MORE NUMEROUS
SHOWERS DEVELOP LATER TODAY. WITH THE NEXT WEATHER SYSTEM IN THE
SERIES. PRECIPITATION CHANCES CONTINUE THROUGH FRIDAY. BELOW NORMAL
HIGH TEMPERATURES WILL CONTINUE AS WELL. CONDITIONS WILL START TO
DRY OUT FOR THE COMING WEEKEND...BUT TEMPERATURES WILL REMAIN BELOW
SEASONAL NORMALS.
&&
.DISCUSSION...
TODAY THROUGH FRIDAY...
BAND OF PRECIP THAT BROUGHT MUCH OF YESTERDAYS RAINFALL TO SOUTH-
CENTRAL ARIZONA HAS BEEN SLOWLY DISSIPATING. HOWEVER...A TRAILING
IMPULSE IS KEEPING SOME ISOLATED VERY LIGHT SHOWERS GOING. HRRR KEEPS
THESE GOING AND EXPANDS THE AREA TO THE LOWER COLORADO RIVER VALLEY
BEFORE SUNRISE. THE NEXT SYSTEM IS ALREADY MOVING INTO CALIFORNIA.
LIFTING MECHANISMS WITH THIS SYSTEM LOOK TO BE SIMILAR TO MONDAYS
WITH SOME LOWER LEVEL CONVERGENCE...UPPER LEVEL DIVERGENCE...AND A
DIV Q BULLSEYE. NAM NOT AS ROBUST AS THE GFS IS IN THOSE FIELDS.
LATEST MODELS INDICATE ITS ARRIVAL AND DEPARTURE WILL BE A BIT FASTER
THAN WAS DEPICTED IN PREVIOUS FORECAST PACKAGE. MADE ADJUSTMENTS TO
THE POPS ACCORDINGLY. SREF INDICATES SOME VERY MODEST CAPE FOR TODAY
AND TONIGHT. SPC HAS GENERAL THUNDER IN THE DAY 1 OUTLOOK FOR OUR
WESTERN AREAS...THOUGH SREF CAPE IS A BIT EAST OF THERE. TAKING THESE
FACTORS INTO ACCOUNT ALONG WITH MODEL LIFTED INDICES...ADDED SLIGHT
CHANCE OF THUNDERSTORMS FOR THIS AFTERNOON AND EVENING. OVERALL...QPF
IS LOOKING HIGHER WITH THIS SYSTEM THAN WHAT WE HAD WITH MONDAYS.
ADVISORY TYPE IMPACTS ARE QUITE POSSIBLE. SNOW LEVELS GENERALLY
REMAIN NEAR OR ABOVE 6000 FEET.
NEXT SYSTEM HAS TWO MAIN WAVES WITH IT. THE FIRST ONE MOVES IN WEDNESDAY
NIGHT AND EXITS OUR EASTERN AREAS THURSDAY EVENING. THE SECOND ONE IS
RIGHT ON ITS HEELS FOR FRIDAY. THE SECOND ONE HAS LESS LIFT GOING FOR
IT. SNOW LEVELS DROP THURSDAY AND FRIDAY...DOWN TO ABOUT 4000-4500 FEET
FRIDAY MORNING AND NOT CHANGING MUCH DURING THE DAY FRIDAY.
ADDITIONAL PRECIP FOR REST OF THIS WEEK...IS 1.5-2.5 INCHES OVER THE
FOOTHILLS AND HIGHER TERRAIN...1.0-1.5 INCHES OVER THE PHOENIX
AREA...AND 0.25-0.75 OVER SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA.
SATURDAY THROUGH MONDAY...
NORTHWEST FLOW AND WEAK DRY ADVECTION ACROSS THE AREA LOOKS LIKELY
THROUGH THE WEEKEND INTO NEXT WEEK...ALTHOUGH THERE`S SOME HINT AT A
DRY TROUGH MOVING THROUGH THE AREA ON SUNDAY /SOME INCREASED CLOUD
COVER AND THAT`S ABOUT IT/. SHOULD THIS TROUGH NOT DEVELOP...WE`LL NEED
TO KEEP AN EYE ON FOG POTENTIAL THIS WEEKEND /SATURDAY OR SUNDAY/ IF
THE BL DOESN`T SUFFICIENTLY DRY OUT. THE PATTERN IS CERTAINLY
CONDUCIVE FOR WIDESPREAD FOG DEVELOPMENT ACROSS THE AREA AND IT
WARRANTS MENTIONING. FAIRLY GOOD AGREEMENT OF STRONG UPPER RIDGING
ACROSS THE AREA BY MONDAY OF NEXT WEEK WITH TEMPERATURES RETURNING TO
EARLY JANUARY NORMALS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SHOWERS WILL CONTINUE TO DISSIPATE IN INTENSITY AND COVERAGE ACROSS
THE PHOENIX METRO AREA THROUGH 06Z-08Z. THEREAFTER...THE BEST CHANCE
FOR PRECIPITATION WILL SHIFT INTO THE HIGHER TERRAIN NORTH AND EAST
OF THE VALLEY. CIGS WILL BE THE MAIN AVIATION WEATHER CONCERN OVER
THE NEXT 24 HOURS. PREPONDERANCE OF MODEL GUIDANCE CONTINUES TO
SUGGEST THAT CIGS WILL LOWER TO 4K FT LATER THIS MORNING AND PERSIST
THROUGH MUCH OF THE DAY TUESDAY. THERE IS ALSO A CHANCE THEY COULD
OCCASIONALLY LOWER TO AROUND 2500 FT AS SATURATION INCREASES BETWEEN
10Z AND 14Z.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NOT MUCH OF A THREAT FOR SHOWER ACTIVITY THROUGH 18Z WED...THOUGH THE
CHANCE FOR PRECIP WILL INCREASE TUESDAY AFTERNOON AND
EVENING...PARTICULARLY AT KIPL. UNTIL THEN...LOWER CIGS BETWEEN 2K
AFN 4K FT WILL PERSIST AT KBLH. SOMEWHAT BETTER CONDITIONS AT KIPL.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
SEVERAL WEATHER DISTURBANCES WILL MOVE THROUGH THE DISTRICTS IN CLOSE
SUCCESSION THIS WEEK WITH HIGHLY VARIABLE RAINFALL OCCURRING EACH
DAY THROUGH FRIDAY...MAINLY EAST OF THE LOWER COLORADO RIVER VALLEY.
RAIN CHANCES TAPER OFF FOR THE WEEKEND. HUMIDITY WILL BE MUCH ABOVE
AVERAGE WITH MINIMUM VALUES NEAR AND ABOVE 45 PERCENT MOST DAYS ON
THE LOWER DESERTS AND MAX VALUES NEAR AND ABOVE 80 PERCENT MUCH OF
THE TIME. VALUES TREND DOWN FROM WEST TO EAST SATURDAY INTO SUNDAY
BUT GENERALLY REMAIN ABOVE 30 PERCENT MOST PLACES. EXPECT WELL BELOW
NORMAL HIGH TEMPERATURES THROUGH FRIDAY WITH DESERT HIGHS IN THE
50S...AND SLIGHT WARMING OVER THE WEEKEND AS HUMIDITIES START TO
FALL OFF. DESPITE THE ACTIVE WEATHER PATTERN NO STRONG WIND EVENTS
ARE EXPECTED BUT JUST BREEZY AT TIMES...MAINLY WEDNESDAY AND
THURSDAY.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ/LEINS
AVIATION...HIRSCH
FIRE WEATHER...AJ/CB
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
404 AM PST TUE JAN 5 2016
...MODERATE TO HEAVY RAIN AND GUSTY WINDS THIS MORNING...
...ANOTHER POTENT STORM FORECAST FOR WEDNESDAY...
.SYNOPSIS...A COLD FRONT INTO THE MORNING WILL PRODUCE HEAVY RAIN
AND LOCALLY STRONG WINDS. ANOTHER STRONG STORM WITH HEAVY RAIN AND
EVEN STRONGER WINDS IS EXPECTED ON WEDNESDAY. MORE SHOWERS WILL
FOLLOW ON THURSDAY.
&&
.DISCUSSION...AS OF 2:30 AM PST TUESDAY...AS FORECAST, WIDESPREAD
RAINFALL IS CURRENTLY MOVING INTO OUR CWA AT THIS HOUR. THIS IS
ASSOCIATED WITH A FRONT THAT IS ALSO ABOUT TO ENTER THE SF
BAY AREA. SO FAR RAIN RATES HAVE GENERALLY BEEN ON THE LIGHT SIDE
WITH THE BULK OF PRECIP OVER THE NORTH BAY. HOWEVER, OVER THE PAST
HOUR POCKETS OF MODERATE TO LOCALLY HEAVY RAINFALL HAVE MADE THEIR
WAY TO THE SAN MATEO AND SAN FRANCISCO COAST. HRRR SEEMS TO HAVE A
GOOD HANDLE ON THE GENERAL TIMING BUT HAS BEEN UNDERDOING AMOUNTS,
SO WILL BE USING THE DATA WITH SOME CAUTION. REGARDLESS, THE MAIN
BAND WILL PROGRESS THROUGH THE BAY AREA OVER THE NEXT COUPLE OF
HOURS WITH SANTA CLARA AND MONTEREY BAY REGION LOOKING AT MORE OF
A 3 TO 6 AM RANGE FOR THE BULK OF THEIR RAIN. AMOUNTS STILL
FORECAST TO BE GENERALLY 1/3" TO 2/3" FOR MOST URBAN SPOTS WITH
1-2" POSSIBLE FOR HIGHER ELEVATION LOCATIONS. WINDS HAVE ALSO BEEN
PICKING UP AS THE FRONT APPROACHES WITH A FAIR NUMBER OF SPOTS NOW
GUSTING TO OVER 25 MPH. SPEEDS WILL GENERALLY PEAK THIS MORNING
AND SHOULD MOSTLY STAY UNDER ADVISORY LEVELS.
FLASH FLOOD WATCH REMAINS IN EFFECT FOR THE BIG SUR REGION
INCLUDING THE SANTA LUCIA MOUNTAINS. TIMING HAS BEEN SLIGHTLY
ADJUSTED TO NOW PUSH THE WATCH TO 10 AM WITH MODELS SUGGESTING THE
POTENTIAL FOR MODERATE TO HEAVY RAIN IN THAT REGION UNTIL LATE IN
THE MORNING. FOR THE REST OF OUR REGION, SO FAR ONLY TWO REPORTS
OF MINOR FLOODING OFF THE CHP PAGE, ALTHOUGH THAT NUMBER SHOULD
INCREASE THROUGH THE NEXT FEW HOURS.
RAIN WILL CHANGE OVER TO SHOWERS AND POSSIBLE THUNDERSTORMS DUE TO
A MORE UNSTABLE ATMOSPHERE WITH PRECIPITATION LIKELY FOR AT LEAST
A PORTION OF THE AFTERNOON AND EVENING HOURS ACROSS THE CWA. A
SECOND POTENT SYSTEM WILL MOVE BACK TO OUR AREA DIRECTLY FROM THE
WEST WITH THE BULK OF THE RAIN FORECAST TO BEGIN AROUND SUNRISE ON
WEDNESDAY. RAIN WILL LIKELY BE MODERATE TO HEAVY AT TIMES WITH THE
MORNING COMMUTE TOMORROW LOOKING VERY CHALLENGING. RAIN WILL
SWITCH TO SHOWERS AND POTENTIALLY THUNDERSTORMS LATER ON
WEDNESDAY. SOUTHERLY WINDS WILL BE GUSTY AND SHOULD BE STRONGER
THAN WITH THE SYSTEM GOING THROUGH TODAY. DAY CREW MAY NEED TO
HOIST A WIND ADVISORY PARTICULARLY ALONG THE COAST PLUS THE NORTH
AND EAST BAY HILLS. RAINFALL AMOUNTS FOR WEDNESDAY ARE FORECAST TO
BE SIMILAR TO AMOUNTS FOR TODAY. GENERALLY 1/2" TO 1" BY THE
EVENING FOR URBAN SPOTS WITH COASTAL RANGES LOOKING FOR 1.5" TO
3". DEPENDING ON HOW THE RAIN TOTALS END UP TODAY AND HOW THE
HIGHER RESOLUTION MODELS LOOK LATER TODAY, ANOTHER FLASH FLOOD
WATCH MAY NEED TO BE ISSUED.
A THIRD AND MUCH WEAKER SYSTEM WILL GO THROUGH ON THURSDAY. THIS
WILL GENERALLY DROP LESS THAN 1/4" IN MOST SPOTS WITH LOCALLY UP
TO 1/2" FOR HIGHER ELEVATION LOCATIONS. SHOWERS WILL GENERALLY
COME TO AN END BY EARLY FRIDAY. THAT BREAK WILL LIKELY BE SHORT AS
WELL AS ANOTHER SYSTEM RACES THROUGH LATE FRIDAY INTO SATURDAY. AT
THIS TIME, THAT SYSTEM DOES NOT LOOK VERY STRONG.
TWO OR THREE MORE SYSTEMS ARE FORECAST FOR NEXT WEEK.
&&
.AVIATION...AS OF 3:59 AM PST TUESDAY...A PAIR OF STORM SYSTEMS
WILL PASS THROUGH THE REGION THROUGH THE 30 HOUR TAF PERIOD. THE
FIRST FRONTAL SYSTEM IS PASSING THROUGH THE REGION NOW... WITH
LIGHT TO MODERATE RAIN AND VFR TO MVFR CIGS REPORTED WITH THE
FROPA. SOUTHERLY WINDS WILL VEER TOWARDS THE WEST INTO AFTERNOON
IN THE POST FRONTAL ENVIRONMENT. CIGS WILL LIFT BRIEFLY INTO THE
AFTERNOON AND EARLY EVENING AHEAD OF THE NEXT FRONTAL SYSTEM THAT
IS EXPECTED TO PASS THROUGH THE REGION BEGINNING AROUND 10-12Z
WED. WINDS WILL BACK TO THE SOUTH-SOUTHEAST AHEAD OF THE NEXT
FRONTAL PASSAGE AND BECOME GUSTY... WITH SOME LOCATIONS SEEING
GUSTS INTO THE 30-40MPH RANGE EARLY WEDNESDAY MORNING.
PREDOMINATELY MVFR TO VFR CIGS EXPECTED WITH SECOND FRONTAL
SYSTEM.
VICINITY OF KSFO...BORDERLINE MVFR CIGS WITH CIGS EXPECTED TO
REMAIN ABOVE CRITICAL 1600FT LEVEL. MODERATE TO HEAVY RAIN THROUGH
THE PREDAWN HOURS... THEN RAIN WILL GRADUALLY TAPER OFF INTO THE
EARLY AFTERNOON. BRIEF IMPROVEMENT IN CONDITIONS FROM 02-06Z
WED... THEN DETERIORATING CIGS AND INCREASING SOUTHEAST WINDS WITH
NEXT FRONTAL PASSAGE AFTER 08Z WED. SOUTHEAST GUSTS UP TO OR
EXCEEDING 40MPH POSSIBLE BY 12Z WED.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...PREDOMINATELY VFR WITH OCCASIONAL
MVFR CIGS ACCOMPANYING FROPA. LIGHT TO MODERATE RAIN NOW THROUGH
00Z WED. THEN IMPROVING CIGS FROM 01Z-09Z WED. DETERIORATING CIGS
AND INCREASING SOUTHEAST WINDS AFTER 10Z WED IN ANTICIPATION OF
SECOND FROPA.
&&
.MARINE...AS OF 03:53 AM PST TUESDAY...A SERIES OF STORMS WILL
MOVE THROUGH THE COASTAL WATERS THIS WEEK LEADING TO BUILDING WEST
SWELLS TODAY THROUGH THURSDAY. EXPECT PERIODS OF MODERATE TO HEAVY
RAIN AND OCCASIONALLY GUSTY WINDS WITH EACH FRONTAL PASSAGE. THE
CURRENT FRONTAL PASSAGE IS PUSHING ONSHORE THIS MORNING. THE NEXT
FRONTAL PASSAGE WILL COME LATE TONIGHT. WINDS AND WAVES TAPER OFF
LATE IN THE WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...HIGH SURF ADVISORY...ALL COASTAL ZONES
FLASH FLOOD WATCH...BIG SUR COAST AND SANTA LUCIA MTNS.
SCA...SF BAY UNTIL 9 AM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 9 AM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 9 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 9 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM UNTIL 9 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 9 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 9 AM
SCA...ROUGH BAR ADVISORY FOR SF BAR UNTIL 3 PM
&&
$$
PUBLIC FORECAST: RWW/BELL
AVIATION: DRP
MARINE: DRP
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
234 AM PST TUE JAN 5 2016
...MODERATE TO HEAVY RAIN AND GUSTY WINDS THIS MORNING...
...ANOTHER POTENT STORM FORECAST FOR WEDNESDAY...
.SYNOPSIS...A COLD FRONT INTO THE MORNING WILL PRODUCE HEAVY RAIN
AND LOCALLY STRONG WINDS. ANOTHER STRONG STORM WITH HEAVY RAIN AND
EVEN STRONGER WINDS IS EXPECTED ON WEDNESDAY. MORE SHOWERS WILL
FOLLOW ON THURSDAY.
&&
.DISCUSSION...AS OF 2:30 AM PST TUESDAY...AS FORECAST, WIDESPREAD
RAINFALL IS CURRENTLY MOVING INTO OUR CWA AT THIS HOUR. THIS IS
ASSOCIATED WITH A FRONT THAT IS ALSO ABOUT TO ENTER THE SF
BAY AREA. SO FAR RAIN RATES HAVE GENERALLY BEEN ON THE LIGHT SIDE
WITH THE BULK OF PRECIP OVER THE NORTH BAY. HOWEVER, OVER THE PAST
HOUR POCKETS OF MODERATE TO LOCALLY HEAVY RAINFALL HAVE MADE THEIR
WAY TO THE SAN MATEO AND SAN FRANCISCO COAST. HRRR SEEMS TO HAVE A
GOOD HANDLE ON THE GENERAL TIMING BUT HAS BEEN UNDERDOING AMOUNTS,
SO WILL BE USING THE DATA WITH SOME CAUTION. REGARDLESS, THE MAIN
BAND WILL PROGRESS THROUGH THE BAY AREA OVER THE NEXT COUPLE OF
HOURS WITH SANTA CLARA AND MONTEREY BAY REGION LOOKING AT MORE OF
A 3 TO 6 AM RANGE FOR THE BULK OF THEIR RAIN. AMOUNTS STILL
FORECAST TO BE GENERALLY 1/3" TO 2/3" FOR MOST URBAN SPOTS WITH
1-2" POSSIBLE FOR HIGHER ELEVATION LOCATIONS. WINDS HAVE ALSO BEEN
PICKING UP AS THE FRONT APPROACHES WITH A FAIR NUMBER OF SPOTS NOW
GUSTING TO OVER 25 MPH. SPEEDS WILL GENERALLY PEAK THIS MORNING
AND SHOULD MOSTLY STAY UNDER ADVISORY LEVELS.
FLASH FLOOD WATCH REMAINS IN EFFECT FOR THE BIG SUR REGION
INCLUDING THE SANTA LUCIA MOUNTAINS. TIMING HAS BEEN SLIGHTLY
ADJUSTED TO NOW PUSH THE WATCH TO 10 AM WITH MODELS SUGGESTING THE
POTENTIAL FOR MODERATE TO HEAVY RAIN IN THAT REGION UNTIL LATE IN
THE MORNING. FOR THE REST OF OUR REGION, SO FAR ONLY TWO REPORTS
OF MINOR FLOODING OFF THE CHP PAGE, ALTHOUGH THAT NUMBER SHOULD
INCREASE THROUGH THE NEXT FEW HOURS.
RAIN WILL CHANGE OVER TO SHOWERS AND POSSIBLE THUNDERSTORMS DUE TO
A MORE UNSTABLE ATMOSPHERE WITH PRECIPITATION LIKELY FOR AT LEAST
A PORTION OF THE AFTERNOON AND EVENING HOURS ACROSS THE CWA. A
SECOND POTENT SYSTEM WILL MOVE BACK TO OUR AREA DIRECTLY FROM THE
WEST WITH THE BULK OF THE RAIN FORECAST TO BEGIN AROUND SUNRISE ON
WEDNESDAY. RAIN WILL LIKELY BE MODERATE TO HEAVY AT TIMES WITH THE
MORNING COMMUTE TOMORROW LOOKING VERY CHALLENGING. RAIN WILL
SWITCH TO SHOWERS AND POTENTIALLY THUNDERSTORMS LATER ON
WEDNESDAY. SOUTHERLY WINDS WILL BE GUSTY AND SHOULD BE STRONGER
THAN WITH THE SYSTEM GOING THROUGH TODAY. DAY CREW MAY NEED TO
HOIST A WIND ADVISORY PARTICULARLY ALONG THE COAST PLUS THE NORTH
AND EAST BAY HILLS. RAINFALL AMOUNTS FOR WEDNESDAY ARE FORECAST TO
BE SIMILAR TO AMOUNTS FOR TODAY. GENERALLY 1/2" TO 1" BY THE
EVENING FOR URBAN SPOTS WITH COASTAL RANGES LOOKING FOR 1.5" TO
3". DEPENDING ON HOW THE RAIN TOTALS END UP TODAY AND HOW THE
HIGHER RESOLUTION MODELS LOOK LATER TODAY, ANOTHER FLASH FLOOD
WATCH MAY NEED TO BE ISSUED.
A THIRD AND MUCH WEAKER SYSTEM WILL GO THROUGH ON THURSDAY. THIS
WILL GENERALLY DROP LESS THAN 1/4" IN MOST SPOTS WITH LOCALLY UP
TO 1/2" FOR HIGHER ELEVATION LOCATIONS. SHOWERS WILL GENERALLY
COME TO AN END BY EARLY FRIDAY. THAT BREAK WILL LIKELY BE SHORT AS
WELL AS ANOTHER SYSTEM RACES THROUGH LATE FRIDAY INTO SATURDAY. AT
THIS TIME, THAT SYSTEM DOES NOT LOOK VERY STRONG.
TWO OR THREE MORE SYSTEMS ARE FORECAST FOR NEXT WEEK.
&&
.AVIATION...AS OF 9:38 PM PST MONDAY...STEADY LIGHT TO LOCALLY
MODERATE RAIN WILL CONTINUE TO SPREAD OVER THE AREA THIS EVENING.
RAIN WILL BE MODERATE TO HEAVY AT TIMES LATE TONIGHT AND TUESDAY
MORNING PER STRENGTHENING WARM AIR ADVECTION THAT IS FOLLOWED BY
THE PASSAGE OF A COLD FRONT EARLY TUESDAY MORNING. SHOWERS LINGER
TUESDAY THEN MORE RAIN ARRIVES TUESDAY NIGHT INTO WEDNESDAY MORNING.
MVFR CIGS AND VSBYS EXCEPT VSBYS LOWERING TO IFR IN MODERATE TO
HEAVY RAIN.
VICINITY OF KSFO...MVFR CIGS. STEADIER RAIN OVERNIGHT WITH A PERIOD
OF GUSTY SE WINDS AND HEAVIER RAIN NEAR THE COLD FRONTAL PASSAGE
TUESDAY MORNING. SHOWERS TUESDAY THEN RAIN RETURNS LATER TUE NIGHT
INTO WEDNESDAY.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR/MVFR CIGS. INCREASING SE WINDS
THIS EVENING BECOMING SW TUESDAY MORNING. RAIN ARRIVING TONIGHT
CONTINUES TUESDAY BEFORE DIMINISHING TO SHOWERS TUESDAY AFTERNOON.
&&
.MARINE...AS OF 9:23 PM PST MONDAY...RAIN WILL BECOME MODERATE TO
HEAVY TONIGHT AND EARLY TUESDAY MORNING AS A COLD FRONT MOVES EAST
OVER THE COASTAL WATERS. WESTERLY SWELLS WILL INCREASE TUESDAY AND
WEDNESDAY WITH LARGER SWELL EXPECTED LATE WEDNESDAY NIGHT THROUGH
THURSDAY. ANOTHER COLD FRONT WILL SWING EAST OVER THE AREA LATE
TUESDAY NIGHT AND WEDNESDAY MORNING WITH MORE RAIN. WINDS AND SEAS
WILL DIMINISH LATE THIS WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...HIGH SURF ADVISORY...ALL COASTAL ZONES
FLASH FLOOD WATCH...BIG SUR COAST AND SANTA LUCIA MTNS.
SCA...SF BAY UNTIL 9 AM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 9 AM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 9 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 9 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM UNTIL 9 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 9 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 9 AM
SCA...ROUGH BAR ADVISORY FOR SF BAR UNTIL 3 PM
&&
$$
PUBLIC FORECAST: RWW/BELL
AVIATION: CANEPA
MARINE: CANEPA
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS MIAMI FL
839 AM EST TUE JAN 5 2016
.UPDATE...
NE WIND SHIFT GRADUALLY SPREADING SOUTHEASTWARD ACROSS EAST COAST
AREAS THIS MRNG. ONCE WINDS SHIFT TO NE...TEMPERATURES WILL RISE
AROUND 10 DEGREES /FROM L60S TO L70S/...THEN LEVEL OFF THROUGH
MUCH OF THE DAY AS SHOWER COVERAGE GRADUALLY INCREASES. WILL BE
MONITORING RADAR TRENDS CLOSELY...FOR POSSIBLE NEED TO BOOST POPS
UP A BIT. FOR NOW...NO CHANGES WARRANTED.
&&
.PREV DISCUSSION... /ISSUED 653 AM EST TUE JAN 5 2016/
AVIATION...
VFR CONDITIONS ARE FORECAST TO PREVAIL THROUGH THE
FORECAST PERIOD EXCEPT FOR A SLIM CHC OF PERIODS OF MVFR CEILINGS
MAINLY ALONG THE SE FL COAST. BUT GIVEN CONFIDENCE ON THAT IS LOW IT
IS NOT CURRENTLY REFLECTED ON THE FORECAST AND WILL AMEND AS NEEDED
IF THIS BECOMES A CONCERN OR ADDRESS IN FUTURE UPDATES. SOMETHING
NOT PICKED UP BY SHORT TERM MOS GUIDANCE BUT PICKED UP BY HRRR AND A
COUPLE OF LOCAL MODEL RUNS IS A LAND BREEZE PARTICULARLY ALONG SE
COAST SITES FROM FLL NORTH THROUGH AROUND DAWN WHEN THE LOW LEVEL NE
FLOW KICKS IN. THIS IS IN LINE WITH CURRENT OBSERVATIONS SO
REFLECTED THE LAND BREEZE ON TAF FORECAST FOR SITES ALONG SE COAST
THE FIRST COUPLE OF HOURS OR SO OF THE FORECAST EARLY THIS MORNING.
BLUSTERY NE WINDS WILL DEVELOP BY MID TO LATE MORNING AT ALL SITES
AND CONTINUE INTO THE EVENING. SOME MOISTURE WILL STREAM NORTH FROM
THE SOUTH TODAY WARRANTING MENTION OF VCSH PARTICULARLY ALONG SE FL
SITES.
PREV DISCUSSION... /ISSUED 441 AM EST TUE JAN 5 2016/
DISCUSSION...
TODAY-WEDNESDAY...COOL START TO THE DAY ACROSS SOUTH FLORIDA WITH
TEMPERATURES RANGING FROM THE UPPER 40S ACROSS GLADES AND HENDRY, TO
THE LOW 50S ALONG THE GULF COAST AND UPPER 50S TO LOW 60S ALONG THE
EAST COAST METRO.
FT LAUDERDALE INTERNATIONAL HAS DROPPED TO 59F SO FAR THIS MORNING,
BREAKING THE OLD RECORD FOR LATEST BELOW 60F TEMP WHICH WAS
PREVIOUSLY 29 DEC 1986. MIAMI INTERNATIONAL CONTINUES TO HOVER
AROUND 60-61F, SO IT MAY ALSO DIP TO 59F OR BELOW THIS MORNING. THE
PREVIOUS RECORD FOR LATEST BELOW 60F TEMP AT MIAMI WAS 23 DEC 1994.
WEST PALM DIPPED TO 57F YESTERDAY MORNING ALSO SETTING A NEW RECORD
FOR LATEST BELOW 60F DAY.
RADAR ALREADY SHOWS LIGHT ECHOES OVER THE ATLANTIC AND EAST COAST,
THOUGH A LOT OF THIS IS LIKELY NOT YET REACHING THE GROUND. DEEPER
MOISTURE ASSOCIATED WITH THE FORMER BOUNDARY LIFTS BACK TO THE NORTH
AS ANOTHER SHORTWAVE SWINGS INTO THE STATE AND SPAWNS A WEAK AREA OF
LOW PRESSURE ALONG THE BOUNDARY OVER THE CENTRAL/NW BAHAMAS. RAIN
CHANCES WILL INCREASE ALONG THE EAST COAST AND FAR SOUTHERN
PENINSULA LATE THIS MORNING AS THIS MOISTURE COMES INTO THE REGION
ALONG WITH THE FORCING AHEAD OF THE TROUGH .
HOW MUCH RAIN WE SEE TONIGHT INTO WEDNESDAY WILL BE DEPENDENT ON
WHERE THE LOW ULTIMATELY FORMS AND WHERE BEST CONVERGENT BANDS END
UP. BUT IT LOOKS LIKE A WET PERIOD THROUGH WEDNESDAY AS THE STATE
ALSO WILL BE IN A FAVORABLE REGION BETWEEN THE DEPARTING AND
APPROACHING JETS. WILL HAVE TO MONITOR FOR A LOCALIZED POTENTIAL
FOCUS FOR HEAVY RAINFALL ALONG THE EAST COAST. COVERAGE AND
INTENSITY OF RAIN WILL DROP OFF INTO THE INTERIOR AND GULF COAST.
A FEW THUNDERSTORMS ARE POSSIBLE, MAINLY OVER THE GULF STREAM
STARTING LATE TONIGHT, WITH THE POSSIBILITY FOR A FEW CREEPING INTO
THE EAST COAST.
TEMPERATURES WILL REMAIN COOL TODAY IN THE LOW 70S WITH A FEW MID
70S POSSIBLE INTO WEDNESDAY ALONG THE EAST COAST AS EAST FLOW
COMPONENT INCREASES OF THE RELATIVELY WARM ATLANTIC WATERS. THIS
MORNING WILL BE THE COOLEST OF THE WEEK WITH TEMPERATURES
ONLY DROPPING INTO UPPER 50S-MID 60S THE NEXT TWO NIGHTS.
INCREASING ONSHORE WINDS ALONG THE ATLANTIC COAST WILL RESULT IN RIP
CURRENT FORMATION AT THE ATLANTIC BEACHES TUE-WED...AND A HIGH RISK
OF RIP CURRENTS IS FORECAST.
THURSDAY-WEEKEND...THE PROGRESSIVE AND UNSETTLED PATTERN CONTINUES
INTO THE UPCOMING WEEKEND AS THE JET STREAM REMAINS ACROSS THE
SOUTHERN TIER OF THE US.
UPPER LEVEL SHORTWAVE AND ASSOCIATED DEVELOPING SURFACE LOW OVER THE
BAHAMAS QUICKLY LIFT OUT TO THE NORTHEAST ON THURS, BRINGING IN A
BRIEF SHOT OF DRIER AIR AND LOW RAIN CHANCES.
THEN THE NEXT SHORTWAVE CROSSING THE SOUTHEASTERN US BRINGS A WEAK
SURFACE FRONT INTO THE STATE ALONG WITH A RETURN OF ADEQUATE, THOUGH
NOT VERY DEEP, MOISTURE. SCATTERED SHOWERS WILL BE IN THE FORECAST
ACROSS THE REGION FOR BOTH FRI AND SAT.
WHILE BOTH THE GFS AND ECMWF ARE IN REMARKABLY GOOD AGREEMENT FOR
THE LATE WEEKEND, THERE ARE SOME SLIGHT DIFFERENCES IN THE SURFACE
PATTERN. THE ECMWF IS A LITTLE STRONGER AND SLOWER WITH THE
REINFORCING FRONT THAN THE GFS AND DRIES THINGS OUT A LITTLE MORE
INTO MONDAY. OVERALL HOWEVER, BOTH SHOW SAT NIGHT INTO SUNDAY AS A
PERIOD OF ENHANCED PRECIP CHANCES THAT MAY LINGER INTO MONDAY FOR AT
LEAST THE SOUTHERN PARTS OF THE REGION.
TEMPS/HUMIDITY WILL MODERATE MID-LATE WEEK...INTO THE UPPER
70S/AROUND 80 FOR HIGHS AND 60S FOR LOWS. THIS WILL BE ABOVE NORMAL,
BUT NOWHERE NEAR THE WARMTH OF LATE DEC.
MARINE...
STRONG EAST-NORTHEAST WINDS 20-25KTS CONTINUE ACROSS BOTH GULF AND
ATLANTIC WATERS INTO WEDNESDAY. SEAS BUILD TO 4-6FT FOR THE OFFSHORE
GULF WATERS AND 9-11FT IN THE GULF STREAM LATER TODAY. HAVE EXTENDED
THE SMALL CRAFT ADVISORY FOR ALL THE WATERS, INCLUDING LAKE
OKEECHOBEE, THROUGH WEDNESDAY MORNING. HAZARDOUS CONDITIONS MAY
LINGER LONGER OVER THE ATLANTIC INTO LATE WEDNESDAY.
WINDS DIMINISH WED NIGHT AS AN AREA OF LOW PRESSURE DEVELOPS JUST TO
OUR SOUTHEAST AND DISRUPTS THE GRADIENT. WINDS BECOME LIGHT NW
BEHIND THE DEPARTING LOW INTO THURS AND THEN S-SW AHEAD OF ANOTHER
SYSTEM INTO FRI. SEAS WILL BE SLOWER TO SUBSIDE, AND HAZARDOUS SEAS
MAY LINGER IN THE GULF STREAM THROUGH FRI.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 69 76 65 80 / 40 70 50 20
FORT LAUDERDALE 66 75 67 79 / 50 80 50 20
MIAMI 67 76 67 80 / 60 80 40 10
NAPLES 59 79 60 78 / 20 60 20 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH WEDNESDAY EVENING FOR FLZ168-172-
173.
AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST WEDNESDAY FOR AMZ610-630-
650-651-670-671.
GM...SMALL CRAFT ADVISORY UNTIL 10 AM EST WEDNESDAY FOR GMZ656-657-
676.
&&
$$
SHORT TERM...23/SK
LONG TERM....88/ALM
AREA FORECAST DISCUSSION
NWS MIAMI FL
653 AM EST TUE JAN 5 2016
.AVIATION...
VFR CONDITIONS ARE FORECAST TO PREVAIL THROUGH THE
FORECAST PERIOD EXCEPT FOR A SLIM CHC OF PERIODS OF MVFR CEILINGS
MAINLY ALONG THE SE FL COAST. BUT GIVEN CONFIDENCE ON THAT IS LOW IT
IS NOT CURRENTLY REFLECTED ON THE FORECAST AND WILL AMEND AS NEEDED
IF THIS BECOMES A CONCERN OR ADDRESS IN FUTURE UPDATES. SOMETHING
NOT PICKED UP BY SHORT TERM MOS GUIDANCE BUT PICKED UP BY HRRR AND A
COUPLE OF LOCAL MODEL RUNS IS A LAND BREEZE PARTICULARLY ALONG SE
COAST SITES FROM FLL NORTH THROUGH AROUND DAWN WHEN THE LOW LEVEL NE
FLOW KICKS IN. THIS IS IN LINE WITH CURRENT OBSERVATIONS SO
REFLECTED THE LAND BREEZE ON TAF FORECAST FOR SITES ALONG SE COAST
THE FIRST COUPLE OF HOURS OR SO OF THE FORECAST EARLY THIS MORNING.
BLUSTERY NE WINDS WILL DEVELOP BY MID TO LATE MORNING AT ALL SITES
AND CONTINUE INTO THE EVENING. SOME MOISTURE WILL STREAM NORTH FROM
THE SOUTH TODAY WARRANTING MENTION OF VCSH PARTICULARLY ALONG SE FL
SITES.
&&
.PREV DISCUSSION... /ISSUED 441 AM EST TUE JAN 5 2016/
DISCUSSION...
TODAY-WEDNESDAY...COOL START TO THE DAY ACROSS SOUTH FLORIDA WITH
TEMPERATURES RANGING FROM THE UPPER 40S ACROSS GLADES AND HENDRY, TO
THE LOW 50S ALONG THE GULF COAST AND UPPER 50S TO LOW 60S ALONG THE
EAST COAST METRO.
FT LAUDERDALE INTERNATIONAL HAS DROPPED TO 59F SO FAR THIS MORNING,
BREAKING THE OLD RECORD FOR LATEST BELOW 60F TEMP WHICH WAS
PREVIOUSLY 29 DEC 1986. MIAMI INTERNATIONAL CONTINUES TO HOVER
AROUND 60-61F, SO IT MAY ALSO DIP TO 59F OR BELOW THIS MORNING. THE
PREVIOUS RECORD FOR LATEST BELOW 60F TEMP AT MIAMI WAS 23 DEC 1994.
WEST PALM DIPPED TO 57F YESTERDAY MORNING ALSO SETTING A NEW RECORD
FOR LATEST BELOW 60F DAY.
RADAR ALREADY SHOWS LIGHT ECHOES OVER THE ATLANTIC AND EAST COAST,
THOUGH A LOT OF THIS IS LIKELY NOT YET REACHING THE GROUND. DEEPER
MOISTURE ASSOCIATED WITH THE FORMER BOUNDARY LIFTS BACK TO THE NORTH
AS ANOTHER SHORTWAVE SWINGS INTO THE STATE AND SPAWNS A WEAK AREA OF
LOW PRESSURE ALONG THE BOUNDARY OVER THE CENTRAL/NW BAHAMAS. RAIN
CHANCES WILL INCREASE ALONG THE EAST COAST AND FAR SOUTHERN
PENINSULA LATE THIS MORNING AS THIS MOISTURE COMES INTO THE REGION
ALONG WITH THE FORCING AHEAD OF THE TROUGH .
HOW MUCH RAIN WE SEE TONIGHT INTO WEDNESDAY WILL BE DEPENDENT ON
WHERE THE LOW ULTIMATELY FORMS AND WHERE BEST CONVERGENT BANDS END
UP. BUT IT LOOKS LIKE A WET PERIOD THROUGH WEDNESDAY AS THE STATE
ALSO WILL BE IN A FAVORABLE REGION BETWEEN THE DEPARTING AND
APPROACHING JETS. WILL HAVE TO MONITOR FOR A LOCALIZED POTENTIAL
FOCUS FOR HEAVY RAINFALL ALONG THE EAST COAST. COVERAGE AND
INTENSITY OF RAIN WILL DROP OFF INTO THE INTERIOR AND GULF COAST.
A FEW THUNDERSTORMS ARE POSSIBLE, MAINLY OVER THE GULF STREAM
STARTING LATE TONIGHT, WITH THE POSSIBILITY FOR A FEW CREEPING INTO
THE EAST COAST.
TEMPERATURES WILL REMAIN COOL TODAY IN THE LOW 70S WITH A FEW MID
70S POSSIBLE INTO WEDNESDAY ALONG THE EAST COAST AS EAST FLOW
COMPONENT INCREASES OF THE RELATIVELY WARM ATLANTIC WATERS. THIS
MORNING WILL BE THE COOLEST OF THE WEEK WITH TEMPERATURES
ONLY DROPPING INTO UPPER 50S-MID 60S THE NEXT TWO NIGHTS.
INCREASING ONSHORE WINDS ALONG THE ATLANTIC COAST WILL RESULT IN RIP
CURRENT FORMATION AT THE ATLANTIC BEACHES TUE-WED...AND A HIGH RISK
OF RIP CURRENTS IS FORECAST.
THURSDAY-WEEKEND...THE PROGRESSIVE AND UNSETTLED PATTERN CONTINUES
INTO THE UPCOMING WEEKEND AS THE JET STREAM REMAINS ACROSS THE
SOUTHERN TIER OF THE US.
UPPER LEVEL SHORTWAVE AND ASSOCIATED DEVELOPING SURFACE LOW OVER THE
BAHAMAS QUICKLY LIFT OUT TO THE NORTHEAST ON THURS, BRINGING IN A
BRIEF SHOT OF DRIER AIR AND LOW RAIN CHANCES.
THEN THE NEXT SHORTWAVE CROSSING THE SOUTHEASTERN US BRINGS A WEAK
SURFACE FRONT INTO THE STATE ALONG WITH A RETURN OF ADEQUATE, THOUGH
NOT VERY DEEP, MOISTURE. SCATTERED SHOWERS WILL BE IN THE FORECAST
ACROSS THE REGION FOR BOTH FRI AND SAT.
WHILE BOTH THE GFS AND ECMWF ARE IN REMARKABLY GOOD AGREEMENT FOR
THE LATE WEEKEND, THERE ARE SOME SLIGHT DIFFERENCES IN THE SURFACE
PATTERN. THE ECMWF IS A LITTLE STRONGER AND SLOWER WITH THE
REINFORCING FRONT THAN THE GFS AND DRIES THINGS OUT A LITTLE MORE
INTO MONDAY. OVERALL HOWEVER, BOTH SHOW SAT NIGHT INTO SUNDAY AS A
PERIOD OF ENHANCED PRECIP CHANCES THAT MAY LINGER INTO MONDAY FOR AT
LEAST THE SOUTHERN PARTS OF THE REGION.
TEMPS/HUMIDITY WILL MODERATE MID-LATE WEEK...INTO THE UPPER
70S/AROUND 80 FOR HIGHS AND 60S FOR LOWS. THIS WILL BE ABOVE NORMAL,
BUT NOWHERE NEAR THE WARMTH OF LATE DEC.
MARINE...
STRONG EAST-NORTHEAST WINDS 20-25KTS CONTINUE ACROSS BOTH GULF AND
ATLANTIC WATERS INTO WEDNESDAY. SEAS BUILD TO 4-6FT FOR THE OFFSHORE
GULF WATERS AND 9-11FT IN THE GULF STREAM LATER TODAY. HAVE EXTENDED
THE SMALL CRAFT ADVISORY FOR ALL THE WATERS, INCLUDING LAKE
OKEECHOBEE, THROUGH WEDNESDAY MORNING. HAZARDOUS CONDITIONS MAY
LINGER LONGER OVER THE ATLANTIC INTO LATE WEDNESDAY.
WINDS DIMINISH WED NIGHT AS AN AREA OF LOW PRESSURE DEVELOPS JUST TO
OUR SOUTHEAST AND DISRUPTS THE GRADIENT. WINDS BECOME LIGHT NW
BEHIND THE DEPARTING LOW INTO THURS AND THEN S-SW AHEAD OF ANOTHER
SYSTEM INTO FRI. SEAS WILL BE SLOWER TO SUBSIDE, AND HAZARDOUS SEAS
MAY LINGER IN THE GULF STREAM THROUGH FRI.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 74 69 76 65 / 30 40 70 50
FORT LAUDERDALE 73 66 75 67 / 40 50 80 50
MIAMI 75 67 76 67 / 40 60 80 40
NAPLES 76 59 79 60 / 10 20 60 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH WEDNESDAY EVENING FOR FLZ168-172-
173.
AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST WEDNESDAY FOR AMZ610-630-
650-651-670-671.
GM...SMALL CRAFT ADVISORY UNTIL 10 AM EST WEDNESDAY FOR GMZ656-657-
676.
&&
$$
SHORT TERM...88/ALM
LONG TERM....88/ALM
AVIATION...52/PS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
654 AM EST TUE JAN 5 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 455 AM EST TUE JAN 5 2016
WV IMAGERY AND RAP ANALYSIS INDICATED MID/UPPER LEVEL RIDGING FROM
THE UPPER MS VALLEY INTO THE WRN GREAT LAKES. AT THE SFC...A TIGHT
PRES GRADIENT AND STRONG SW FLOW PREVAILED OVER LAKE SUPERIOR AND
UPPER MI BTWN HIGH PRES OVER THE ERN LAKES AND FRONT/TROUGH FROM NW
ONTARIO INTO THE NRN PLAINS. MOISTENING WITH THE SW WIND ACROSS LAKE
MI HAS BROUGH LOW CLOUDS INTO FAR ERN UPPER MI...S AND E FROM ISQ TO
ERY. A BAND OF CLOUDS HAS ALSO DEVELOPED NE FROM THE BAY OF GREEN
BAY. UPSTREAM A LARGER AREA OF LOW CLOUDS FROM ERN MN AND FAR WRN WI
WAS GRADUALLY LIFTING TO THE NNE TO HYR-EAU.
TODAY...HIGH RES MODELS 925 MB RH FCSTS...IN LINE WITH CURRENT
TRENDS...SUGGEST THAT THE CLOUDS OVER NW WI WILL GRADUALLY SPREAD
INTO THE SW PORTION OF UPPER MI TODAY BUT THIN OUT OVER CNTRL
AREAS...ESPECIALLY WHERE DOWNSLOPE SW WINDS PREVAIL. THE CLOUDS OVER
THE ERN CWA ARE EXPECTED TO PUSH FARTHER TO THE EAST. EVEN WITH
LIMITED DAYTIME MIXING AS TEMPS CLIMB INTO THE UPPER 20S TO AROUND
30...WINDS WILL BECOME GUSTY TO AROUND 25-30 MPH.
TONIGHT...A SHORTWAVE TROUGH MOVING THROUGH NRN ONTARIO WILL HELP
DRAG A WEAK COLD FRONT INTO LAKE SUPERIOR. 850-700 MB FGEN
ASSOCIATED WITH THE FRONT ALONG WITH WEAK ISENTROPIC LIFT ALONG WITH
MOISTENING FROM WSW WINDS ACROSS LAKE SUPERIOR WILL SUPPORT A SLIGHT
CHANCE FOR LIGHT SNOW SHOWERS OR FLURRIES INTO THE KEWEENAW. WITH
THE MOIST LAYER ONLY TO AROUND -10C...SOME FZDZ MAY ALSO BE
POSSIBLE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 306 AM EST TUE JAN 5 2016
MAY SEE A FEW LIGHT LES SHOWERS OVER THE NRN PORTIONS OF THE
KEWEENAW WED MORNING WITH SW WINDS AND 850MB TEMPS AROUND -9C...BUT
NOT SIGNIFICANT ACCUMULATIONS. A TROUGH AND SFC FRONT STALL OUT OVER
THE AREA ON WED AND STAY INTO THU NIGHT. DEVELOPMENT OF LOW-MID
LEVEL FGEN FORCING WILL PROMOTE AN ELONGATED AREA OF LIGHT SNOW OVER
MAINLY WRN/NWRN UPPER MI WED AFTERNOON AND EVENING. A SHORTWAVE AND
WAA WILL THEN LEAD TO WIDESPREAD LIGHT SNOW WED NIGHT INTO
THU...ENDING TIME UNCERTAIN WITH DIFFERING MODEL SOLUTIONS. EXPECT
SNOW TO LIQUID RATIOS AROUND 10 TO 1 GIVEN MOST OF THE WEAK LIFT IS
BELOW THE DGZ...WHICH WHEN COMBINED WITH TOTAL QPF AMOUNTS OF 0.10-
0.25 INCHES (LOWEST SE AND GREATEST OVER THE W AND NW) EXPECT
GENERALLY 1 TO JUST OVER 2 INCHES OF SNOW IN THE 24-30 HOUR PERIOD.
ANOTHER PERIOD OF LIGHT AND INSIGNIFICANT SNOW IS EXPECTED FRI AND
SAT AS A WEAK LOW MOVES FROM MO AT 12Z FRI TO QUEBEC OR JAMES BAY
(DEPENDING ON MODEL SOLUTION) BY 00Z SUN. STILL LOOKS LIKE BEST
FORCING/PRECIP WILL BE OVER THE ERN AND MAYBE SRN UPPER MI IN THE
FRI AFTERNOON/FRI NIGHT TIME FRAME. STILL SEEING MODEL DIFFERENCES
ON TIMING. COULD SEE SOME RAIN MIX IN FRI AFTERNOON OVER SERN UPPER
MI AS WET BULB ZERO HEIGHTS RISE WITH HIGHS IN THE MID 30S. OVERALL
ONLY EXPECTING A VERY MINOR 1-3 INCHES OF SNOW OVER 36 HOURS.
MAIN STORY IN THE LONG TERM IS THAT MODEL PERSIST IN SHOWING AN
ACTIVE WAVE MOVING INTO THE AREA SAT NIGHT AND DEEPENING INTO A
CLOSED UPPER LOW OVER OR NEAR THE CWA LATE SUN AND SUN NIGHT. 850MB
TEMPS AS LOW AS -25C ARE CO-LOCATED WITH THE LOW. MODELS ALSO
CONTINUE TO SHOW ANOTHER WAVE MOVING IN MID NEXT WEEK...WHICH WILL
REINFORCE THE COLD AIR. TEMPS WILL GO FROM HIGHS IN THE UPPER 20S TO
MID 30S AND LOWS IN THE 20S LATE IN THE WEEK TO HIGHS IN THE SINGLE
DIGITS TO TEENS ABOVE ZERO AND LOWS IN THE SINGLE DIGITS ABOVE AND
BELOW ZERO EARLY NEXT WEEK. NW-W WIND SNOWBELTS WILL CERTAINLY SEE
PERSISTENT LES SAT NIGHT THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...BUT NOT EXPECTING WARNING AMOUNTS AT THIS TIME DUE TO SMALL
FLAKE SIZE GIVEN VERY COLD TEMPS (CLOUD LAYER COLDER THAN THE
PREFERRED DGZ). THAT COLD AIR WILL ALSO MARK THE FIRST TIME OUR
OFFICE WILL FALL BELOW ZERO SINCE MARCH 28...2015. THROUGH JANUARY
3...THAT MAKES A 281 DAY STREAK AND IS CURRENTLY TIED FOR THE 16TH
LONGEST STREAK. IF THE CURRENT FORECAST HOLDS...WE WILL MAKE IT TO
AROUND 288 OR 289 DAYS...WHICH WOULD BE RIGHT AROUND THE 9TH LONGEST
STREAK OF TEMPERATURES AT OR ABOVE ZERO.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 654 AM EST TUE JAN 5 2016
STRONG SW WINDS ABOVE A NOCTURNAL INVERSION WILL RESULT IN LLWS
UNTIL LATE MORNING. WITH SOME DAYTIME HEATING...EXPECT GUSTY SW
WINDS BY LATE MORNING THROUGH THE AFTERNOON. HOW QUICKLY THIS SW
FLOW TAPS MOISTER AIR TO THE SW OF UPPER MI IS ANOTHER FCST CONCERN.
RIGHT NOW...EXPECT VFR CONDITIONS TO PREVAIL THROUGH TODAY...WITH
DOWNSLOPE NATURE OF THE SW FLOW HELPING TO MAINTAIN LOWER RH. BUT
EVEN THE DRIER GUIDANCE HINTS LOW CLOUDS WILL ARRIVE TONIGHT...SO
FCST MVFR CIGS TO ARRIVE THIS EVENING. THE BEST CHANCE FOR IFR CIGS
WILL BE AT IWD OVERNIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 525 AM EST TUE JAN 5 2016
A TIGHT PRES GRADIENT BTWN A DEPARTING HIGH PRES RIDGE AND LOW PRES
TROUGH FROM HUDSON BAY TO THE NRN PLAINS WILL SUPPORT SW GALES
ACROSS LAKE SUPERIOR TODAY. THE GALES WILL BEGIN TO DIMINISH
TONIGHT. WINDS WILL DIMINISH FURTHER WED/THU TO MOSTLY UNDER 20KT AS
A LOW PRES TROUGH SETTLES OVER THE UPPER GREAT LAKES. WINDS WILL
INCREASE AGAIN FRI/SAT AS LOW PRES LIFTS NE INTO THE GREAT LAKES
REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ243-244-265>267.
GALE WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR LSZ162.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LSZ263-264.
LAKE MICHIGAN...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
526 AM EST TUE JAN 5 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 455 AM EST TUE JAN 5 2016
WV IMAGERY AND RAP ANALYSIS INDICATED MID/UPPER LEVEL RIDGING FROM
THE UPPER MS VALLEY INTO THE WRN GREAT LAKES. AT THE SFC...A TIGHT
PRES GRADIENT AND STRONG SW FLOW PREVAILED OVER LAKE SUPERIOR AND
UPPER MI BTWN HIGH PRES OVER THE ERN LAKES AND FRONT/TROUGH FROM NW
ONTARIO INTO THE NRN PLAINS. MOISTENING WITH THE SW WIND ACROSS LAKE
MI HAS BROUGH LOW CLOUDS INTO FAR ERN UPPER MI...S AND E FROM ISQ TO
ERY. A BAND OF CLOUDS HAS ALSO DEVELOPED NE FROM THE BAY OF GREEN
BAY. UPSTREAM A LARGER AREA OF LOW CLOUDS FROM ERN MN AND FAR WRN WI
WAS GRADUALLY LIFTING TO THE NNE TO HYR-EAU.
TODAY...HIGH RES MODELS 925 MB RH FCSTS...IN LINE WITH CURRENT
TRENDS...SUGGEST THAT THE CLOUDS OVER NW WI WILL GRADUALLY SPREAD
INTO THE SW PORTION OF UPPER MI TODAY BUT THIN OUT OVER CNTRL
AREAS...ESPECIALLY WHERE DOWNSLOPE SW WINDS PREVAIL. THE CLOUDS OVER
THE ERN CWA ARE EXPECTED TO PUSH FARTHER TO THE EAST. EVEN WITH
LIMITED DAYTIME MIXING AS TEMPS CLIMB INTO THE UPPER 20S TO AROUND
30...WINDS WILL BECOME GUSTY TO AROUND 25-30 MPH.
TONIGHT...A SHORTWAVE TROUGH MOVING THROUGH NRN ONTARIO WILL HELP
DRAG A WEAK COLD FRONT INTO LAKE SUPERIOR. 850-700 MB FGEN
ASSOCIATED WITH THE FRONT ALONG WITH WEAK ISENTROPIC LIFT ALONG WITH
MOISTENING FROM WSW WINDS ACROSS LAKE SUPERIOR WILL SUPPORT A SLIGHT
CHANCE FOR LIGHT SNOW SHOWERS OR FLURRIES INTO THE KEWEENAW. WITH
THE MOIST LAYER ONLY TO AROUND -10C...SOME FZDZ MAY ALSO BE
POSSIBLE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 306 AM EST TUE JAN 5 2016
MAY SEE A FEW LIGHT LES SHOWERS OVER THE NRN PORTIONS OF THE
KEWEENAW WED MORNING WITH SW WINDS AND 850MB TEMPS AROUND -9C...BUT
NOT SIGNIFICANT ACCUMULATIONS. A TROUGH AND SFC FRONT STALL OUT OVER
THE AREA ON WED AND STAY INTO THU NIGHT. DEVELOPMENT OF LOW-MID
LEVEL FGEN FORCING WILL PROMOTE AN ELONGATED AREA OF LIGHT SNOW OVER
MAINLY WRN/NWRN UPPER MI WED AFTERNOON AND EVENING. A SHORTWAVE AND
WAA WILL THEN LEAD TO WIDESPREAD LIGHT SNOW WED NIGHT INTO
THU...ENDING TIME UNCERTAIN WITH DIFFERING MODEL SOLUTIONS. EXPECT
SNOW TO LIQUID RATIOS AROUND 10 TO 1 GIVEN MOST OF THE WEAK LIFT IS
BELOW THE DGZ...WHICH WHEN COMBINED WITH TOTAL QPF AMOUNTS OF 0.10-
0.25 INCHES (LOWEST SE AND GREATEST OVER THE W AND NW) EXPECT
GENERALLY 1 TO JUST OVER 2 INCHES OF SNOW IN THE 24-30 HOUR PERIOD.
ANOTHER PERIOD OF LIGHT AND INSIGNIFICANT SNOW IS EXPECTED FRI AND
SAT AS A WEAK LOW MOVES FROM MO AT 12Z FRI TO QUEBEC OR JAMES BAY
(DEPENDING ON MODEL SOLUTION) BY 00Z SUN. STILL LOOKS LIKE BEST
FORCING/PRECIP WILL BE OVER THE ERN AND MAYBE SRN UPPER MI IN THE
FRI AFTERNOON/FRI NIGHT TIME FRAME. STILL SEEING MODEL DIFFERENCES
ON TIMING. COULD SEE SOME RAIN MIX IN FRI AFTERNOON OVER SERN UPPER
MI AS WET BULB ZERO HEIGHTS RISE WITH HIGHS IN THE MID 30S. OVERALL
ONLY EXPECTING A VERY MINOR 1-3 INCHES OF SNOW OVER 36 HOURS.
MAIN STORY IN THE LONG TERM IS THAT MODEL PERSIST IN SHOWING AN
ACTIVE WAVE MOVING INTO THE AREA SAT NIGHT AND DEEPENING INTO A
CLOSED UPPER LOW OVER OR NEAR THE CWA LATE SUN AND SUN NIGHT. 850MB
TEMPS AS LOW AS -25C ARE CO-LOCATED WITH THE LOW. MODELS ALSO
CONTINUE TO SHOW ANOTHER WAVE MOVING IN MID NEXT WEEK...WHICH WILL
REINFORCE THE COLD AIR. TEMPS WILL GO FROM HIGHS IN THE UPPER 20S TO
MID 30S AND LOWS IN THE 20S LATE IN THE WEEK TO HIGHS IN THE SINGLE
DIGITS TO TEENS ABOVE ZERO AND LOWS IN THE SINGLE DIGITS ABOVE AND
BELOW ZERO EARLY NEXT WEEK. NW-W WIND SNOWBELTS WILL CERTAINLY SEE
PERSISTENT LES SAT NIGHT THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...BUT NOT EXPECTING WARNING AMOUNTS AT THIS TIME DUE TO SMALL
FLAKE SIZE GIVEN VERY COLD TEMPS (CLOUD LAYER COLDER THAN THE
PREFERRED DGZ). THAT COLD AIR WILL ALSO MARK THE FIRST TIME OUR
OFFICE WILL FALL BELOW ZERO SINCE MARCH 28...2015. THROUGH JANUARY
3...THAT MAKES A 281 DAY STREAK AND IS CURRENTLY TIED FOR THE 16TH
LONGEST STREAK. IF THE CURRENT FORECAST HOLDS...WE WILL MAKE IT TO
AROUND 288 OR 289 DAYS...WHICH WOULD BE RIGHT AROUND THE 9TH LONGEST
STREAK OF TEMPERATURES AT OR ABOVE ZERO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1236 AM EST TUE JAN 5 2016
INCRSG SW WIND TNGT ABOVE LLVL INVRN ENHANCED BY NOCTURNAL COOLING
WL RESULT IN LLWS AT ALL 3 SITES THIS MRNG. WITH SOME DAYTIME
HEATING...EXPECT GUSTY SW WINDS BY LATE MRNG THRU THE AFTN. HOW
QUICKLY THIS SW FLOW TAPS MOISTER AIR WELL TO THE SW OF UPR MI IS
ANOTHER FCST CONCERN. RIGHT NOW...EXPECT VFR CONDITIONS TO PREVAIL
THRU TODAY...WITH DOWNSLOPE NATURE OF THE SW FLOW HELPING TO
MAINTAIN LOWER RH. BUT EVEN THE DRIER GUIDANCE HINTS LO CLDS WL
ARRIVE TNGT...SO FCST MVFR CIGS TO ARRIVE THIS EVNG.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 525 AM EST TUE JAN 5 2016
A TIGHT PRES GRADIENT BTWN A DEPARTING HIGH PRES RIDGE AND LOW PRES
TROUGH FROM HUDSON BAY TO THE NRN PLAINS WILL SUPPORT SW GALES
ACROSS LAKE SUPERIOR TODAY. THE GALES WILL BEGIN TO DIMINISH
TONIGHT. WINDS WILL DIMINISH FURTHER WED/THU TO MOSTLY UNDER 20KT AS
A LOW PRES TROUGH SETTLES OVER THE UPPER GREAT LAKES. WINDS WILL
INCREASE AGAIN FRI/SAT AS LOW PRES LIFTS NE INTO THE GREAT LAKES
REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ265>267.
GALE WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR LSZ162.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LSZ263-264.
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ243-244.
LAKE MICHIGAN...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
526 AM CST TUE JAN 5 2016
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 426 AM CST TUE JAN 5 2016
MORE ACTIVE STRETCH BEGINS WEDNESDAY AFTERNOON...CONTINUING INTO
THE WEEKEND. SPENT MOST WORK TRYING TO PIN DOWN PRECIPITATION
TYPES...TIMING...AND CHANCES FOR THE LIGHTER PRECIPITATION
WED/THU...AND WEATHER SYSTEM ON THURSDAY NIGHT AND FRIDAY.
GOES WATER VAPOR IMAGERY SHOWING A NICE SHORTWAVE TROUGH MOVING
TOWARD KMSP WITH MAIN INFLUENCE IN THE 500MB AND ABOVE LAYER PER
RAP TROPOPAUSE FOLD DEPTH TO 400 MB. AIR MASS ALOFT IS QUITE DRY
AND DO NOT EXPECT WEATHER FROM IT. MORE IMPRESSIVE SHORTWAVE
TROUGH OVER SWRN NEW MEXICO AT 09Z CLEARLY VISIBLE AND LIFTING
NORTHEAST...THIS WILL BRING PRECIPITATION IN FOR
WEDNESDAY AFTERNOON-NIGHT...AND NEXT TROUGH APPROACHING SRN CA IS
LATE THU-FRI WEATHER.
LOW CLOUDS IN FOG PRODUCT HAVE BEEN PRETTY BEHAVED TONIGHT SLIDING
NORTH IN THE STRONGER LOW-LEVEL SOUTHERLY FLOW. HOWEVER...THE
SOUTHERN PORTION IS ANCHORED NEAR KDSM AND I-80...SO THIS ISNT ALL
THAT EASY. BOTTOM LINE IS KEPT WI MOSTLY SUNNY WITH MN/IA SLOWLY
SEEING MORE SUNSHINE AS DAY PROGRESSES. GSD HRRR MODEL RUN SEEMS
TO HAVE THE BEST IDEA ON NORTHWARD TRACK.
WEDNESDAY AFTERNOON AND OVERNIGHT...
CONSISTENT SIGNAL CONTINUES FOR THIS PERIOD WITH VERY WEAK
FRONTOGENESIS TO THE NORTHWEST OVER MN...SHORTWAVE TROUGH FROM
NEW MEXICO APPROACHING THE AREA WITH WEAK QVECTOR
CONVERGENCE...WEAK ISENTROPIC UPGLIDE /280-290K/...AND SOME
INCREASE IN MOISTURE /2-4 G/KG/ ON A PLUME FROM WRN IA INTO MN
WEDNESDAY AFTERNOON. THIS ALL EVOLVES EASTWARD WEDNESDAY NIGHT
HOWEVER...IT STILL APPEARS THE BEST LIFT IS NORTHWESTERN AREAS OF
THE FORECAST AREA. KEPT FORECAST ABOUT THE SAME BUT ADDED MORE
TIMING TO PRECIPITATION CHANCES. STILL LOOKING LIKE A 1 INCH
SNOW. THERE IS SOME SUGGESTION OF A BIT OF A WARM LAYER BEFORE
FULL SATURATION OCCURS WHICH COULD MIX IN A BIT OF SLEET FOR AN
HOUR OR SO.
THE SHORTWAVE TROUGH WILL SHIFT EAST THURSDAY AND TAKE WITH IT
THE DEEP SATURATION...AND THE FORECAST AREA WILL LOSE ICE CLOUD
FROM SW TO NE. THIS SIGNAL HAS BEEN IN THE MODEL GUIDANCE...ACROSS
THE MODELS...FOR DAYS NOW...AND HAVE DECIDED TO ADD THE
POSSIBILITY OF DZ/FZDZ TO THE FORECAST. THE SATURATED LIQUID LAYER
IS OVER 2KM DEEP WITH SOME RESIDUAL LIFT AS THE TROUGH MOVES
EAST...WITH ABOUT 2-3 UB/S OF LIFT IN THE LAYER. HAVE LOWERED THE
PRECIPITATION CHANCES THURSDAY...SO IT LOOKS LIKE A CHANCE OF
FZDZ IN THE MORNING...THEN DZ IN THE AFTERNOON AS TEMPERATURES
WARM. ONLY A SKIM OF ICING WOULD BE POSSIBLE IF ANYTHING
MATERIALIZES AT ALL.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 426 AM CST TUE JAN 5 2016
THURSDAY NIGHT THROUGH FRIDAY...
THE 05.06Z MODEL GUIDANCE HAS REALLY COME INTO BETTER AGREEMENT
ON THE STRONGER SHORTWAVE TROUGH OF THE WEEK AND THE ONSET OF
PRECIPITATION INTO THE SOUTH THURSDAY EVENING WITH WARM ADVECTION
BURST....AND THE DEFORMATION BAND ROTATING NORTHWEST FRIDAY IN
CONCERT WITH A LOW-LEVEL INVERTED TROUGH. IT APPEARS THERE ARE
TWO INDIVIDUAL WAVES THAT WILL AFFECT THE AREA SO THIS PERIOD IS A
BIT MORE COMPLEX. THE LOW-LEVEL CYCLONE /925-850MB/ APPEARS TO BE
MORE CONSOLIDATED...WHICH COULD LEAD TO A FAIRLY NICE DEFORMATION
REGION WITH THIS SYSTEM FRIDAY. WITH THE TRACK THROUGH NRN IL...IT
APPEARS ONLY CENTRAL/SWRN WI AND FAR NERN IA WILL HAVE
PRECIPITATION TYPE ISSUES...AND SNOW TO THE NORTHWEST. EARLY SNOW
AMOUNTS SNOW LOOK LIKE 1-3 INCHES...WITH SOME RAIN OR SLEET
FURTHER SOUTHEAST. WILL NEED TO KEEP OUR EYE ON THIS ONE AS IT HAS
SOME GOOD ATTRIBUTES FOR A BIT HIGHER IMPACT IF IT STRENGTHENS
MORE.
SATURDAY THROUGH MONDAY...
DEEP TROUGH MOVE IN FROM THE NORTHWEST WITH PROBABLY A LIGHT SNOW
BURST ON THE FRONT...AND STRONG COLD ADVECTION. SATURDAY WILL BE
THE LAST NEAR NORMAL DAY WITH GOOD AGREEMENT ON THE COLD WEEK
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 526 AM CST TUE JAN 5 2016
THE AREA OF PERSISTENT LOW CLOUDS OVER NORTHERN IOWA AND EASTERN
MINNESOTA HAS FINALLY BEGUN TO MOVE NORTH. THE CR-HRRR HAS BEEN
SHOWING THIS TREND FOR SEVERAL RUNS AND IT LOOKS LIKE AS THESE
LIFT NORTH...THEY WILL STAY TO THE WEST OF KLSE AND SHOULD MOVE
OUT OF KRST BETWEEN 13 AND 14Z. AFTER THAT...THE REST OF THE
PERIOD WILL HAVE VFR CONDITIONS WITH JUST SOME HIGH LEVEL CLOUDS
EXPECTED TO MOVE OVER. THERE WILL BE A PRETTY TIGHT GRADIENT IN
PLACE TO PRODUCE SOME GUSTY SOUTH WINDS AT KRST. PUSHED BACK THE
ONSET OF THE GUSTS A COUPLE OF HOURS FROM THE PREVIOUS FORECAST AS
IT SHOULD CLEAR JUST LONG ENOUGH TO HELP STRENGTHEN THE LOW LEVEL
INVERSION WITH SOME SURFACE COOLING JUST ENOUGH THAT THE GOOD LOW
LEVEL LAPSE RATES WILL BE DELAYED SOME. HOWEVER...ONCE THE GUSTS
GET GOING...THE FORECAST SOUNDINGS FROM THE 05.06Z NAM INDICATE
THE LOW LEVEL LAPSE RATES REMAIN IN PLACE TO KEEP SOME GUSTS GOING
OVERNIGHT AS WELL. FOR NOW...DID NOT INCLUDE ANY GUSTS AT KLSE AS
THE VALLEY MAY KEEP THE LOW LEVEL INVERSION IN PLACE AND NOT ALLOW
THE GOOD LOW LEVEL LAPSE RATES TO DEVELOP.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
428 AM CST TUE JAN 5 2016
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 426 AM CST TUE JAN 5 2016
MORE ACTIVE STRETCH BEGINS WEDNESDAY AFTERNOON...CONTINUING INTO
THE WEEKEND. SPENT MOST WORK TRYING TO PIN DOWN PRECIPITATION
TYPES...TIMING...AND CHANCES FOR THE LIGHTER PRECIPITATION
WED/THU...AND WEATHER SYSTEM ON THURSDAY NIGHT AND FRIDAY.
GOES WATER VAPOR IMAGERY SHOWING A NICE SHORTWAVE TROUGH MOVING
TOWARD KMSP WITH MAIN INFLUENCE IN THE 500MB AND ABOVE LAYER PER
RAP TROPOPAUSE FOLD DEPTH TO 400 MB. AIR MASS ALOFT IS QUITE DRY
AND DO NOT EXPECT WEATHER FROM IT. MORE IMPRESSIVE SHORTWAVE
TROUGH OVER SWRN NEW MEXICO AT 09Z CLEARLY VISIBLE AND LIFTING
NORTHEAST...THIS WILL BRING PRECIPITATION IN FOR
WEDNESDAY AFTERNOON-NIGHT...AND NEXT TROUGH APPROACHING SRN CA IS
LATE THU-FRI WEATHER.
LOW CLOUDS IN FOG PRODUCT HAVE BEEN PRETTY BEHAVED TONIGHT SLIDING
NORTH IN THE STRONGER LOW-LEVEL SOUTHERLY FLOW. HOWEVER...THE
SOUTHERN PORTION IS ANCHORED NEAR KDSM AND I-80...SO THIS ISNT ALL
THAT EASY. BOTTOM LINE IS KEPT WI MOSTLY SUNNY WITH MN/IA SLOWLY
SEEING MORE SUNSHINE AS DAY PROGRESSES. GSD HRRR MODEL RUN SEEMS
TO HAVE THE BEST IDEA ON NORTHWARD TRACK.
WEDNESDAY AFTERNOON AND OVERNIGHT...
CONSISTENT SIGNAL CONTINUES FOR THIS PERIOD WITH VERY WEAK
FRONTOGENESIS TO THE NORTHWEST OVER MN...SHORTWAVE TROUGH FROM
NEW MEXICO APPROACHING THE AREA WITH WEAK QVECTOR
CONVERGENCE...WEAK ISENTROPIC UPGLIDE /280-290K/...AND SOME
INCREASE IN MOISTURE /2-4 G/KG/ ON A PLUME FROM WRN IA INTO MN
WEDNESDAY AFTERNOON. THIS ALL EVOLVES EASTWARD WEDNESDAY NIGHT
HOWEVER...IT STILL APPEARS THE BEST LIFT IS NORTHWESTERN AREAS OF
THE FORECAST AREA. KEPT FORECAST ABOUT THE SAME BUT ADDED MORE
TIMING TO PRECIPITATION CHANCES. STILL LOOKING LIKE A 1 INCH
SNOW. THERE IS SOME SUGGESTION OF A BIT OF A WARM LAYER BEFORE
FULL SATURATION OCCURS WHICH COULD MIX IN A BIT OF SLEET FOR AN
HOUR OR SO.
THE SHORTWAVE TROUGH WILL SHIFT EAST THURSDAY AND TAKE WITH IT
THE DEEP SATURATION...AND THE FORECAST AREA WILL LOSE ICE CLOUD
FROM SW TO NE. THIS SIGNAL HAS BEEN IN THE MODEL GUIDANCE...ACROSS
THE MODELS...FOR DAYS NOW...AND HAVE DECIDED TO ADD THE
POSSIBILITY OF DZ/FZDZ TO THE FORECAST. THE SATURATED LIQUID LAYER
IS OVER 2KM DEEP WITH SOME RESIDUAL LIFT AS THE TROUGH MOVES
EAST...WITH ABOUT 2-3 UB/S OF LIFT IN THE LAYER. HAVE LOWERED THE
PRECIPITATION CHANCES THURSDAY...SO IT LOOKS LIKE A CHANCE OF
FZDZ IN THE MORNING...THEN DZ IN THE AFTERNOON AS TEMPERATURES
WARM. ONLY A SKIM OF ICING WOULD BE POSSIBLE IF ANYTHING
MATERIALIZES AT ALL.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 426 AM CST TUE JAN 5 2016
THURSDAY NIGHT THROUGH FRIDAY...
THE 05.06Z MODEL GUIDANCE HAS REALLY COME INTO BETTER AGREEMENT
ON THE STRONGER SHORTWAVE TROUGH OF THE WEEK AND THE ONSET OF
PRECIPITATION INTO THE SOUTH THURSDAY EVENING WITH WARM ADVECTION
BURST....AND THE DEFORMATION BAND ROTATING NORTHWEST FRIDAY IN
CONCERT WITH A LOW-LEVEL INVERTED TROUGH. IT APPEARS THERE ARE
TWO INDIVIDUAL WAVES THAT WILL AFFECT THE AREA SO THIS PERIOD IS A
BIT MORE COMPLEX. THE LOW-LEVEL CYCLONE /925-850MB/ APPEARS TO BE
MORE CONSOLIDATED...WHICH COULD LEAD TO A FAIRLY NICE DEFORMATION
REGION WITH THIS SYSTEM FRIDAY. WITH THE TRACK THROUGH NRN IL...IT
APPEARS ONLY CENTRAL/SWRN WI AND FAR NERN IA WILL HAVE
PRECIPITATION TYPE ISSUES...AND SNOW TO THE NORTHWEST. EARLY SNOW
AMOUNTS SNOW LOOK LIKE 1-3 INCHES...WITH SOME RAIN OR SLEET
FURTHER SOUTHEAST. WILL NEED TO KEEP OUR EYE ON THIS ONE AS IT HAS
SOME GOOD ATTRIBUTES FOR A BIT HIGHER IMPACT IF IT STRENGTHENS
MORE.
SATURDAY THROUGH MONDAY...
DEEP TROUGH MOVE IN FROM THE NORTHWEST WITH PROBABLY A LIGHT SNOW
BURST ON THE FRONT...AND STRONG COLD ADVECTION. SATURDAY WILL BE
THE LAST NEAR NORMAL DAY WITH GOOD AGREEMENT ON THE COLD WEEK
BEGINNING ON SUNDAY WITH SINGLE DIGIT HIGHS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1140 PM CST MON JAN 4 2016
05.0530Z IR SATELLITE SHOWS AN AREA OF IFR STRATUS FROM NORTH-
CENTRAL IA INTO EAST-CENTRAL MN...MOVING MORE NORTH THAN EAST
AROUND 10 MPH. WHILE KRST WILL REMAIN IFR THROUGH THE NIGHT...
LATEST FORECAST GUIDANCE SUGGESTS KLSE WILL LIKELY SKIRT THE
EASTERN EDGE OF THESE LOWER CLOUDS AND COULD GO EITHER WAY. WILL
TREND MORE VFR AT KLSE GIVEN INCREASING SOUTHERLY LOW-LEVEL FLOW
AND THE LATEST CLOUD MOVEMENT TRENDS...WITH ONLY A FOUR HOUR IFR
TEMPO GROUP FROM 05.08 TO 08.12Z. STRONG SOUTHERLY WINDS SHOULD
LIMIT FOG FORMATION WITH ONLY SOME MVFR RESTRICTIONS TO VISIBILITY.
IF LOW CLOUDS MOVE FAR ENOUGH NORTH AND DISSIPATE TUESDAY MORNING...
EXPECT A MOSTLY VFR DAY AT BOTH TAF AIRFIELDS. SOUTHERLY GUSTS AT
KRST UP TO 30 KTS POSSIBLE WITH LESSER WINDS AT KLSE THROUGH THE
PERIOD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...ROGERS
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
949 AM PST TUE JAN 5 2016
.SYNOPSIS...LINGERING SHOWERS WILL CONTINUE THROUGH THIS
AFTERNOON IN WAKE OF THIS MORNING`S FRONTAL PASSAGE. ANOTHER STORM
SYSTEM WILL IMPACT THE REGION LATE TONIGHT INTO WEDNESDAY MORNING
WITH LOCALLY HEAVY RAINFALL AND STRONGER WINDS. ADDITIONAL SHOWERS
WILL THEN BE POSSIBLE THROUGH THURSDAY.
&&
.DISCUSSION...AS OF 09:03 AM PST TUESDAY...THE FRONTAL BOUNDARY
THAT BROUGHT WIDESPREAD PRECIPITATION TO THE REGION THIS MORNING
CONTINUES TO PUSH INLAND. IN WAKE OF THE FRONTAL PASSAGE, LIGHT TO
OCCASIONALLY MODERATE RAINFALL CONTINUES WITH SOME ENHANCEMENT IN
RAINFALL RATES ALONG THE COAST OVER THE PAST HOUR. EXPECTING THESE
RAIN SHOWERS TO PERSIST INTO THE EARLY AFTERNOON WITH A BRIEF
BREAK IN PRECIPITATION EXPECTED LATE THIS EVENING ACROSS PORTIONS
OF THE REGION. ALSO, CANNOT RULE OUT AN ISOLATED THUNDERSTORM OR
TWO AS THE ATMOSPHERE BECOMES MORE UNSTABLE.
HAVE CANCELED THE FLASH FLOOD WATCH FOR SOUTHERN MONTEREY BAY
REGION AND THE SANTA LUCIA MOUNTAINS THAT WAS IN EFFECT THROUGH
THIS MORNING AS RAINFALL AMOUNTS WERE LESS THAN ORIGINALLY FORECAST
OVER THAT REGION. HOWEVER, WILL NEED TO EVALUATE THE POTENTIAL
FOR ADDITIONAL CONCERNS AS THE NEXT SYSTEM REMAINS ON TRACK TO
IMPACT THE REGION OVERNIGHT TONIGHT INTO WEDNESDAY MORNING. AT
THIS TIME, THIS NEXT SYSTEM APPEARS TO BRING SIMILAR RAINFALL
AMOUNTS TO THE REGION ON WEDNESDAY MORNING WITH LINGERING
PRECIPITATION INTO THURSDAY. PLEASE SEE THE PREVIOUS FORECAST
DISCUSSION BELOW FOR MORE DETAILS AND LOOK FOR OUR UPDATED
FORECAST LATER THIS AFTERNOON.
&&
.PREV DISCUSSION...AS OF 2:30 AM PST TUESDAY...AS FORECAST,
WIDESPREAD RAINFALL IS CURRENTLY MOVING INTO OUR CWA AT THIS HOUR.
THIS IS ASSOCIATED WITH A FRONT THAT IS ALSO ABOUT TO ENTER THE SF
BAY AREA. SO FAR RAIN RATES HAVE GENERALLY BEEN ON THE LIGHT SIDE
WITH THE BULK OF PRECIP OVER THE NORTH BAY. HOWEVER, OVER THE PAST
HOUR POCKETS OF MODERATE TO LOCALLY HEAVY RAINFALL HAVE MADE THEIR
WAY TO THE SAN MATEO AND SAN FRANCISCO COAST. HRRR SEEMS TO HAVE A
GOOD HANDLE ON THE GENERAL TIMING BUT HAS BEEN UNDERDOING AMOUNTS,
SO WILL BE USING THE DATA WITH SOME CAUTION. REGARDLESS, THE MAIN
BAND WILL PROGRESS THROUGH THE BAY AREA OVER THE NEXT COUPLE OF
HOURS WITH SANTA CLARA AND MONTEREY BAY REGION LOOKING AT MORE OF
A 3 TO 6 AM RANGE FOR THE BULK OF THEIR RAIN. AMOUNTS STILL
FORECAST TO BE GENERALLY 1/3" TO 2/3" FOR MOST URBAN SPOTS WITH
1-2" POSSIBLE FOR HIGHER ELEVATION LOCATIONS. WINDS HAVE ALSO BEEN
PICKING UP AS THE FRONT APPROACHES WITH A FAIR NUMBER OF SPOTS NOW
GUSTING TO OVER 25 MPH. SPEEDS WILL GENERALLY PEAK THIS MORNING
AND SHOULD MOSTLY STAY UNDER ADVISORY LEVELS.
FLASH FLOOD WATCH REMAINS IN EFFECT FOR THE BIG SUR REGION
INCLUDING THE SANTA LUCIA MOUNTAINS. TIMING HAS BEEN SLIGHTLY
ADJUSTED TO NOW PUSH THE WATCH TO 10 AM WITH MODELS SUGGESTING THE
POTENTIAL FOR MODERATE TO HEAVY RAIN IN THAT REGION UNTIL LATE IN
THE MORNING. FOR THE REST OF OUR REGION, SO FAR ONLY TWO REPORTS
OF MINOR FLOODING OFF THE CHP PAGE, ALTHOUGH THAT NUMBER SHOULD
INCREASE THROUGH THE NEXT FEW HOURS.
RAIN WILL CHANGE OVER TO SHOWERS AND POSSIBLE THUNDERSTORMS DUE TO
A MORE UNSTABLE ATMOSPHERE WITH PRECIPITATION LIKELY FOR AT LEAST
A PORTION OF THE AFTERNOON AND EVENING HOURS ACROSS THE CWA. A
SECOND POTENT SYSTEM WILL MOVE BACK TO OUR AREA DIRECTLY FROM THE
WEST WITH THE BULK OF THE RAIN FORECAST TO BEGIN AROUND SUNRISE ON
WEDNESDAY. RAIN WILL LIKELY BE MODERATE TO HEAVY AT TIMES WITH THE
MORNING COMMUTE TOMORROW LOOKING VERY CHALLENGING. RAIN WILL
SWITCH TO SHOWERS AND POTENTIALLY THUNDERSTORMS LATER ON
WEDNESDAY. SOUTHERLY WINDS WILL BE GUSTY AND SHOULD BE STRONGER
THAN WITH THE SYSTEM GOING THROUGH TODAY. DAY CREW MAY NEED TO
HOIST A WIND ADVISORY PARTICULARLY ALONG THE COAST PLUS THE NORTH
AND EAST BAY HILLS. RAINFALL AMOUNTS FOR WEDNESDAY ARE FORECAST TO
BE SIMILAR TO AMOUNTS FOR TODAY. GENERALLY 1/2" TO 1" BY THE
EVENING FOR URBAN SPOTS WITH COASTAL RANGES LOOKING FOR 1.5" TO
3". DEPENDING ON HOW THE RAIN TOTALS END UP TODAY AND HOW THE
HIGHER RESOLUTION MODELS LOOK LATER TODAY, ANOTHER FLASH FLOOD
WATCH MAY NEED TO BE ISSUED.
A THIRD AND MUCH WEAKER SYSTEM WILL GO THROUGH ON THURSDAY. THIS
WILL GENERALLY DROP LESS THAN 1/4" IN MOST SPOTS WITH LOCALLY UP
TO 1/2" FOR HIGHER ELEVATION LOCATIONS. SHOWERS WILL GENERALLY
COME TO AN END BY EARLY FRIDAY. THAT BREAK WILL LIKELY BE SHORT AS
WELL AS ANOTHER SYSTEM RACES THROUGH LATE FRIDAY INTO SATURDAY. AT
THIS TIME, THAT SYSTEM DOES NOT LOOK VERY STRONG.
TWO OR THREE MORE SYSTEMS ARE FORECAST FOR NEXT WEEK.
&&
.AVIATION...AS OF 9:48 AM PST TUESDAY...DIFFICULT AND DYNAMIC
FORECAST AS ONE SYSTEM IS CURRENTLY SWEEPING THROUGH THE BAY AREA
THIS MORNING AND ANOTHER SYSTEM APPROACHES FROM THE WEST. IN THE
NEAR TERM...LIGHT TO MODERATE RAIN WILL CONTINUE THROUGH EARLY
THIS AFTERNOON (20ZISH) WITH SOME CIGS LIFTING THIS AFTERNOON. A
BRIEF BREAK IN THE ACTION THEN RAIN RETURNS LATE TONIGHT IMPACTING
THE AM RUSH AGAIN FOR WEDNESDAY. WINDS WILL DEFINITELY BE
PROBLEMATIC WITH NAILING DOWN DIRECTION AND SPEED AT TIMES.
HOWEVER...WINDS WILL LIKELY INCREASE TONIGHT AND REMAIN GUSTY
TOMORROW. OVERALL CONF IS LOW TO MODERATE.
LASTLY...MODELS AND CURRENT PUBLIC FORECAST HAS A POSSIBILITY OF TSTORMS
THIS AFTERNOON AND WEDNESDAY...BUT CONF IS NOT HIGH ENOUGH TO HAVE
TSRA IN ANY TAF LOCATION.
VICINITY OF KSFO...LIGHT TO MODERATE RAIN AND SE WINDS WILL
CONTINUE THROUGH 19 TO 20Z. LATEST GUIDANCE SUGGESTS A WIND SHIFT
AROUND 19 TO 20Z AND BUOYS OFF THE COAST HAVE ALREADY SHIFTED.
THEREFORE...SE TO SW AROUND 19Z WILL BE IN THE SFO TAF. SW TO W
WINDS THIS AFTERNOON WITH VCSH. RAIN RETURNS TONIGHT AFTER 06Z AND
MAY BE HEAVY TOMORROW AM AROUND 12Z.
SFO BRIDGE APPROACH...FOR THE MOST PART SIMILAR TO KSFO...BUT AT TIMES CONDITIONS
WILL LIKELY VARY IN SUCH A SMALL DISTANCE FROM THE BRIDGE TO THE
RUNWAY WITH CIGS AND WINDS.
MONTEREY BAY AREA TERMINALS...LIGHT TO MODERATE RAIN WITH MVFR
CONDITIONS THROUGH THIS AFTERNOON. VCSH THIS EVENING WITH RAIN
RETURNING LATE TONIGHT. GUSTY SE WINDS WILL BE POSSIBLE AT KSNS.
&&
.MARINE...AS OF 09:36 AM PST TUESDAY...ACTIVE WEATHER WILL
CONTINUE OVER THE COASTAL WATERS AS SEVERAL STORMS MOVE THROUGH
THE REGION. ONE STORM WILL EXIT THE REGION TODAY...BUT ANOTHER
STORM WILL APPROACH TONIGHT. THE APPROACHING STORM WILL BRING
ANOTHER ROUND OF MODERATE TO HEAVY RAIN AND GUSTY WINDS. SWELLS
WILL BUILD THROUGH THE PERIOD AS WELL.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...HIGH SURF ADVISORY...ENTIRE COASTLINE
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: RGASS
AVIATION: MM
MARINE: MM
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
920 AM PST TUE JAN 5 2016
.SYNOPSIS...LINGERING SHOWERS WILL CONTINUE THROUGH THIS
AFTERNOON IN WAKE OF THIS MORNING`S FRONTAL PASSAGE. ANOTHER STORM
SYSTEM WILL IMPACT THE REGION LATE TONIGHT INTO WEDNESDAY MORNING
WITH LOCALLY HEAVY RAINFALL AND STRONGER WINDS. ADDITIONAL SHOWERS
WILL THEN BE POSSIBLE THROUGH THURSDAY.
&&
.DISCUSSION...AS OF 09:03 AM PST TUESDAY...THE FRONTAL BOUNDARY
THAT BROUGHT WIDESPREAD PRECIPITATION TO THE REGION THIS MORNING
CONTINUES TO PUSH INLAND. IN WAKE OF THE FRONTAL PASSAGE, LIGHT TO
OCCASIONALLY MODERATE RAINFALL CONTINUES WITH SOME ENHANCEMENT IN
RAINFALL RATES ALONG THE COAST OVER THE PAST HOUR. EXPECTING THESE
RAIN SHOWERS TO PERSIST INTO THE EARLY AFTERNOON WITH A BRIEF
BREAK IN PRECIPITATION EXPECTED LATE THIS EVENING ACROSS PORTIONS
OF THE REGION. ALSO, CANNOT RULE OUT AN ISOLATED THUNDERSTORM OR
TWO AS THE ATMOSPHERE BECOMES MORE UNSTABLE.
HAVE CANCELED THE FLASH FLOOD WATCH FOR SOUTHERN MONTEREY BAY
REGION AND THE SANTA LUCIA MOUNTAINS THAT WAS IN EFFECT THROUGH
THIS MORNING AS RAINFALL AMOUNTS WERE LESS THAN ORIGINALLY FORECAST
OVER THAT REGION. HOWEVER, WILL NEED TO EVALUATE THE POTENTIAL
FOR ADDITIONAL CONCERNS AS THE NEXT SYSTEM REMAINS ON TRACK TO
IMPACT THE REGION OVERNIGHT TONIGHT INTO WEDNESDAY MORNING. AT
THIS TIME, THIS NEXT SYSTEM APPEARS TO BRING SIMILAR RAINFALL
AMOUNTS TO THE REGION ON WEDNESDAY MORNING WITH LINGERING
PRECIPITATION INTO THURSDAY. PLEASE SEE THE PREVIOUS FORECAST
DISCUSSION BELOW FOR MORE DETAILS AND LOOK FOR OUR UPDATED
FORECAST LATER THIS AFTERNOON.
&&
.PREV DISCUSSION...AS OF 2:30 AM PST TUESDAY...AS FORECAST,
WIDESPREAD RAINFALL IS CURRENTLY MOVING INTO OUR CWA AT THIS HOUR.
THIS IS ASSOCIATED WITH A FRONT THAT IS ALSO ABOUT TO ENTER THE SF
BAY AREA. SO FAR RAIN RATES HAVE GENERALLY BEEN ON THE LIGHT SIDE
WITH THE BULK OF PRECIP OVER THE NORTH BAY. HOWEVER, OVER THE PAST
HOUR POCKETS OF MODERATE TO LOCALLY HEAVY RAINFALL HAVE MADE THEIR
WAY TO THE SAN MATEO AND SAN FRANCISCO COAST. HRRR SEEMS TO HAVE A
GOOD HANDLE ON THE GENERAL TIMING BUT HAS BEEN UNDERDOING AMOUNTS,
SO WILL BE USING THE DATA WITH SOME CAUTION. REGARDLESS, THE MAIN
BAND WILL PROGRESS THROUGH THE BAY AREA OVER THE NEXT COUPLE OF
HOURS WITH SANTA CLARA AND MONTEREY BAY REGION LOOKING AT MORE OF
A 3 TO 6 AM RANGE FOR THE BULK OF THEIR RAIN. AMOUNTS STILL
FORECAST TO BE GENERALLY 1/3" TO 2/3" FOR MOST URBAN SPOTS WITH
1-2" POSSIBLE FOR HIGHER ELEVATION LOCATIONS. WINDS HAVE ALSO BEEN
PICKING UP AS THE FRONT APPROACHES WITH A FAIR NUMBER OF SPOTS NOW
GUSTING TO OVER 25 MPH. SPEEDS WILL GENERALLY PEAK THIS MORNING
AND SHOULD MOSTLY STAY UNDER ADVISORY LEVELS.
FLASH FLOOD WATCH REMAINS IN EFFECT FOR THE BIG SUR REGION
INCLUDING THE SANTA LUCIA MOUNTAINS. TIMING HAS BEEN SLIGHTLY
ADJUSTED TO NOW PUSH THE WATCH TO 10 AM WITH MODELS SUGGESTING THE
POTENTIAL FOR MODERATE TO HEAVY RAIN IN THAT REGION UNTIL LATE IN
THE MORNING. FOR THE REST OF OUR REGION, SO FAR ONLY TWO REPORTS
OF MINOR FLOODING OFF THE CHP PAGE, ALTHOUGH THAT NUMBER SHOULD
INCREASE THROUGH THE NEXT FEW HOURS.
RAIN WILL CHANGE OVER TO SHOWERS AND POSSIBLE THUNDERSTORMS DUE TO
A MORE UNSTABLE ATMOSPHERE WITH PRECIPITATION LIKELY FOR AT LEAST
A PORTION OF THE AFTERNOON AND EVENING HOURS ACROSS THE CWA. A
SECOND POTENT SYSTEM WILL MOVE BACK TO OUR AREA DIRECTLY FROM THE
WEST WITH THE BULK OF THE RAIN FORECAST TO BEGIN AROUND SUNRISE ON
WEDNESDAY. RAIN WILL LIKELY BE MODERATE TO HEAVY AT TIMES WITH THE
MORNING COMMUTE TOMORROW LOOKING VERY CHALLENGING. RAIN WILL
SWITCH TO SHOWERS AND POTENTIALLY THUNDERSTORMS LATER ON
WEDNESDAY. SOUTHERLY WINDS WILL BE GUSTY AND SHOULD BE STRONGER
THAN WITH THE SYSTEM GOING THROUGH TODAY. DAY CREW MAY NEED TO
HOIST A WIND ADVISORY PARTICULARLY ALONG THE COAST PLUS THE NORTH
AND EAST BAY HILLS. RAINFALL AMOUNTS FOR WEDNESDAY ARE FORECAST TO
BE SIMILAR TO AMOUNTS FOR TODAY. GENERALLY 1/2" TO 1" BY THE
EVENING FOR URBAN SPOTS WITH COASTAL RANGES LOOKING FOR 1.5" TO
3". DEPENDING ON HOW THE RAIN TOTALS END UP TODAY AND HOW THE
HIGHER RESOLUTION MODELS LOOK LATER TODAY, ANOTHER FLASH FLOOD
WATCH MAY NEED TO BE ISSUED.
A THIRD AND MUCH WEAKER SYSTEM WILL GO THROUGH ON THURSDAY. THIS
WILL GENERALLY DROP LESS THAN 1/4" IN MOST SPOTS WITH LOCALLY UP
TO 1/2" FOR HIGHER ELEVATION LOCATIONS. SHOWERS WILL GENERALLY
COME TO AN END BY EARLY FRIDAY. THAT BREAK WILL LIKELY BE SHORT AS
WELL AS ANOTHER SYSTEM RACES THROUGH LATE FRIDAY INTO SATURDAY. AT
THIS TIME, THAT SYSTEM DOES NOT LOOK VERY STRONG.
TWO OR THREE MORE SYSTEMS ARE FORECAST FOR NEXT WEEK.
&&
.AVIATION...AS OF 3:59 AM PST TUESDAY...A PAIR OF STORM SYSTEMS
WILL PASS THROUGH THE REGION THROUGH THE 30 HOUR TAF PERIOD. THE
FIRST FRONTAL SYSTEM IS PASSING THROUGH THE REGION NOW... WITH
LIGHT TO MODERATE RAIN AND VFR TO MVFR CIGS REPORTED WITH THE
FROPA. SOUTHERLY WINDS WILL VEER TOWARDS THE WEST INTO AFTERNOON
IN THE POST FRONTAL ENVIRONMENT. CIGS WILL LIFT BRIEFLY INTO THE
AFTERNOON AND EARLY EVENING AHEAD OF THE NEXT FRONTAL SYSTEM THAT
IS EXPECTED TO PASS THROUGH THE REGION BEGINNING AROUND 10-12Z
WED. WINDS WILL BACK TO THE SOUTH-SOUTHEAST AHEAD OF THE NEXT
FRONTAL PASSAGE AND BECOME GUSTY... WITH SOME LOCATIONS SEEING
GUSTS INTO THE 30-40MPH RANGE EARLY WEDNESDAY MORNING.
PREDOMINATELY MVFR TO VFR CIGS EXPECTED WITH SECOND FRONTAL
SYSTEM.
VICINITY OF KSFO...BORDERLINE MVFR CIGS WITH CIGS EXPECTED TO
REMAIN ABOVE CRITICAL 1600FT LEVEL. MODERATE TO HEAVY RAIN THROUGH
THE PREDAWN HOURS... THEN RAIN WILL GRADUALLY TAPER OFF INTO THE
EARLY AFTERNOON. BRIEF IMPROVEMENT IN CONDITIONS FROM 02-06Z
WED... THEN DETERIORATING CIGS AND INCREASING SOUTHEAST WINDS WITH
NEXT FRONTAL PASSAGE AFTER 08Z WED. SOUTHEAST GUSTS UP TO OR
EXCEEDING 40MPH POSSIBLE BY 12Z WED.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...PREDOMINATELY VFR WITH OCCASIONAL
MVFR CIGS ACCOMPANYING FROPA. LIGHT TO MODERATE RAIN NOW THROUGH
00Z WED. THEN IMPROVING CIGS FROM 01Z-09Z WED. DETERIORATING CIGS
AND INCREASING SOUTHEAST WINDS AFTER 10Z WED IN ANTICIPATION OF
SECOND FROPA.
&&
.MARINE...AS OF 09:03 AM PST TUESDAY...ACTIVE WEATHER WILL
CONTINUE OVER THE COASTAL WATERS AS SEVERAL STORMS MOVE THROUGH
THE REGION. ONE STORM WILL EXIT THE REGION TODAY...BUT ANOTHER
STORM WILL APPROACH TONIGHT. THE APPROACHING STORM WILL BRING
ANOTHER ROUND OF MODERATE TO HEAVY RAIN AND GUSTY WINDS. SWELLS
WILL BUILD THROUGH THE PERIOD AS WELL.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...HIGH SURF ADVISORY...ALL COASTAL ZONES
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: RGASS
AVIATION: DRP
MARINE: MM
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AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
349 PM EST TUE JAN 5 2016
...HAZARDOUS CONDITIONS FOR SMALL CRAFT PERSIST THROUGH
TONIGHT...
.SYNOPSIS...
20Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A CURRENTLY LESS
AMPLIFIED UPPER LEVEL PATTERN ACROSS THE CONUS. MAIN EAST COAST
LONGWAVE TROUGH IS QUICKLY EXITING THE NORTHEAST COAST INTO THE
WESTERN ATLANTIC...WITH A BROAD REGION OF UPPER RIDGING SPRAWLING
ACROSS THE EASTERN CONUS IN ITS WAKE. OUR FORECAST AREA RESIDES
WITHIN A DEEP LAYER OF MID/UPPER LEVEL SOUTHWESTERLY WINDS
UNDERNEATH THE SOUTHERN STREAM FLOW. WITHIN THIS SOUTHERN STREAM
WE ARE WATCHING A HEALTHY SHORTWAVE TROUGH WHICH HAS EJECTED FROM
NORTHERN MEXICO AND IS NOW CROSSING THE WESTERN GULF OF MEXICO. WV
IMAGERY CONTINUES TO SHOWS AN INCREASING PLUME OF MID/HIGH LEVEL
MOISTURE STREAMING OUT AHEAD OF THIS ENERGY OVER THE EASTERN GULF
AND FLORIDA PENINSULA. THIS SHORTWAVE WILL BECOME BETTER ORGANIZED
PER GFS/ECMWF AS IT CROSSES THE GULF DURING THE NEXT 12-18
HOURS...AND WILL CAUSE OUR FORECAST TO BECOME A BIT TRICKY LATE
TONIGHT INTO WEDNESDAY...ESPECIALLY THE FURTHER SOUTH AND
SOUTHEAST FROM THE I-4 CORRIDOR ONE TRAVELS.
AT THE SURFACE...OUR WEATHER IS DOMINATED BY STRONG HIGH PRESSURE
CENTERED OVER THE MID-ATLANTIC STATES...BUT RIDGING ALL THE WAY
SOUTH TO THE FL PENINSULA/EASTERN GULF OF MEXICO. THE TIGHT
GRADIENT ON THE SOUTHERN PERIPHERY OF THIS RIDGE ALONG WITH
RESIDUAL COLD AIR ADVECTION (CAA) HAS THE WINDS REALLY RAMPED UP
OVER THE EASTERN GULF OF MEXICO...WHERE SMALL CRAFT ADVISORIES
REMAIN IN EFFECT THROUGH THE OVERNIGHT.
THE TROP DRIED OUT SIGNIFICANTLY BETWEEN MONDAY MORNING AND
THIS MORNING...WITH THE 12Z KTBW SOUNDING SAMPLING A PW VALUE OF
ONLY 0.44". THIS VALUE IS RIGHT ABOUT AT THE 10TH PERCENTILE FOR
EARLY JANUARY. HOWEVER...THE DRYING OF THE COLUMN ENDED EARLIER
TODAY...AND WE HAVE BEGUN A GRADUAL MOISTENING THAT WILL WORK ITS
WAY SLOWLY SOUTH TO NORTH. CROSS SECTION ANALYSIS FROM ALL
RELIABLE GUIDANCE SHOW THIS TREND OF A GENERAL ERODING OF THE
DRIEST LAYER ABOVE THE SURFACE THROUGH THE OVERNIGHT...WITH THE
PROCESS QUICKEST AND MOST DRAMATIC OVER THE SOUTHERN HALF OF THE
PENINSULA.
AT LEAST THROUGH THE EVENING HOURS...THE DRY AIR ALOFT WILL WIN
ACROSS OUR FORECAST ZONES...AND HAVE NO MEASURABLE RAIN MENTIONED
IN THE FORECAST. IT WOULD NOT BE IMPOSSIBLE TO SEE A FEW
SPRINKLES WORK AS FAR NORTH AS LEE/CHARLOTTE AND HIGHLANDS
COUNTIES...BUT SHOULD NOT BE IMPACTFUL FOR OUTDOOR ACTIVITIES.
THE TIGHT GRADIENT WILL KEEP CONDITIONS RATHER BREEZY THROUGH THE
EARLY EVENING HOURS WITH SEASONABLY COOL TEMPERATURES. HIGH TEMPS
THIS AFTERNOON HAVE REACHED CLOSE TO 60 OVER THE FAR NORTH...TO
THE MIDDLE 60S THROUGH THE I-4 CORRIDOR...AND TO WITHIN A COUPLE
DEGREES OF 70 OVER THE SOUTHERN ZONES. HIGH TEMPS SHOULD NOW HAVE
BEEN REACHED AND WILL SEE THESE READINGS BEGIN TO SLIDE BACK DOWN
IN THE COMING FEW HOURS.
&&
.SHORT TERM (TONIGHT THROUGH WEDNESDAY)...
LATER TONIGHT INTO WEDNESDAY IS WHEN THE FORECAST STARTS TO BECOME
A LITTLE MORE TRICKY. THE GOOD NEWS COMPARED TO THE FORECAST
SCENARIO EARLIER TODAY IS THAT THE 12Z NAM HAS COME AROUND CLOSER
TO RECENT GFS/ECMWF SOLUTIONS...WHEN COMPARED TO ITS PREVIOUS 06Z
RUN...WHICH WAS CONSIDERABLY WETTER FOR WEDNESDAY SOUTH OF THE I-4
CORRIDOR. AT LEAST THIS TREND ADDS SOME FORECAST CONFIDENCE THAT
WAS MORE IN QUESTION EARLIER.
SHORTWAVE ENERGY WILL BE MIGRATING TOWARD THE REGION
OVERNIGHT/EARLY WEDNESDAY WITH INCREASING SYNOPTIC SUPPORT/DEEP
LAYER Q-VECTOR CONVERGENCE OVERSPREADING THE REGION IN ADVANCE.
RATHER IMPRESSIVE COUPLING OF LEFT EXIT REGION AND RIGHT ENTRANCE
REGION OF PAIRED UPPER JETS WILL ALSO BE TAKING PLACE. WHILE THE
DEEP LAYER HEIGHT FALLS/Q-VECTOR CONVERGENCE IS BROAD ENOUGH TO
ENCOMPASS MUCH OF THE REGION...THE BEST JET COUPLING AND
RESULTING UPPER DIVERGENCE FIELDS COINCIDENT WITH THE HEIGHT
FALLS ARE SHOWN TO MAXIMIZE OVER THE FAR SOUTHERN FL
PENINSULA/FLORIDA STRAITS AND BAHAMAS. IT WILL BE THIS AREA WHERE
IT IS AGREED UPON IN THE NWP GUIDANCE THAT WE WILL SEE SURFACE
CYCLOGENESIS COMMENCE OVERNIGHT AND LIFT NORTHEASTWARD WEDNESDAY
AND WEDNESDAY NIGHT. WITH THE LOW DEVELOPING IN THIS AREA...THE
STRONGEST AND MOST EFFICIENT LOWER LEVEL FRONTOGENESIS ALSO STAYS
JUST TO THE SOUTH AND SOUTHEAST OF OUR ZONES. AT LEAST IN THE
LOWER LEVELS...THIS PLACEMENT WOULD RESULT IN OUR SOUTHERN ZONES
RESIDING WITH A ZONE OF GENERAL SUPPRESSION (DESCENDING AIR) ON
THE COLD SIDE OF THE FRONTAL THERMAL CIRCULATION.
ALL THIS BEGIN SAID...WILL BE A VERY CLOSE CALL BETWEEN OUR FAR
SOUTHERN AND INTERIOR SOUTHERN ZONES
(HIGHLANDS/DESOTO/CHARLOTTE/LEE) AND THE NORTHERN EXTENT OF THE
POTENTIALLY ORGANIZED RAINFALL ZONE LATE TONIGHT INTO WEDNESDAY.
AS MENTIONED ABOVE...THE GFS/ECMWF HAVE BEEN CONSISTENT IN KEEPING
THE BEST LIFT AND MOST ORGANIZED SHOWER ACTIVITY GENERALLY OUT OF
OUR AREA FOR SEVERAL PAST MODEL RUNS. LOOKING AT THE INDIVIDUAL
GEFS MEMBERS...MOST ALSO KEEP SIGNIFICANT PRECIP SOUTH OF OUR
AREA...AND THE STANDARD DEVIATION OF PRECIP AMOUNTS AMONG THE
MEMBERS IS LESS THAN 1/10TH OF AN INCH OVER THE SOUTHERN ZONES.
THIS LOW A VALUE TENDS TO SUGGEST HIGHER CONFIDENCE IN THE MEAN
ENSEMBLE VALUES. THE NAM WHILE STILL FURTHER WEST AND NORTHWEST
WITH ITS LIFT AND RESULTING QPF FIELDS...HAS TRENDED
BACK/DRIER/LESS LIFT OVER OUR AREA FROM EARLIER SOLUTIONS.
FINALLY...AT LEAST WORTH A MENTION...TOOK A QUICK LOOK AT THE
05/00Z RUN OF THE PARALLEL NEXT GENERATION GFS CURRENTLY BEING
TESTED...AND IT WAS VERY SIMILAR TO THE PAST FEW OPERATIONAL GFS
RUNS. WILL HAVE TO KEEP SOME SHOWER CHANCES IN THE FORECAST BASED
ON THE INCREASINGLY FAVORABLE MOISTURE PROFILES...AND OVERALL
PRESENCE OF WEAK SYNOPTIC LIFT...BUT FEELING IS THAT A WASHOUT
FOR THESE SOUTHERN ZONES ON WEDNESDAY IS UNLIKELY. FURTHER NORTH
TOWARD TAMPA BAY AND NATURE COAST ZONES...JUST MENTIONING A FEW
SPRINKLES ON WEDNESDAY. MANY LOCATIONS ALONG AND NORTH OF THE I-4
CORRIDOR ARE LIKELY TO NOT EVEN SEE MEASURABLE PRECIP.
GIVEN THE SYSTEM PASSING OVERHEAD...WILL SEE A MOSTLY CLOUDY DAY
FOR MOST LOCATIONS WEDNESDAY...HOWEVER HIGH TEMPERATURES SHOULD
BE UP SEVERAL DEGREES FROM WHAT WE ARE SEEING THIS AFTERNOON.
&&
.LONG TERM (THURSDAY THROUGH NEXT TUESDAY...
TEMPERATURES TO START THE MID/LONG TERM PERIOD WILL BE ABOVE
CLIMATOLOGICAL NORMS AS THEY CONTINUE TO REBOUND FROM THE COOLER
TEMPERATURES WE SAW TO START THIS WEEK. ON THURSDAY A SHORTWAVE WILL
MOVE INTO THE SOUTHERN TENNESSEE VALLEY AS IT EXITS THE SOUTHERN
PLAIN STATES. MODELS CONTINUE TO DISAGREE ON THE INTENSITY OF THE
NEXT SYSTEM WHICH WILL APPROACH THE AREA LATE ON THURSDAY INTO
FRIDAY. 12Z ECMWF REMAINS MORE ROBUST COMPARED TO THE GFS. THAT
BEING SAID...WITH AMPLE MOISTURE IN PLACE AND UPPER LEVEL FORCING IN
THE FORM OF A ~120 KNOT SOUTHERN STREAM JET OVERHEAD SEEMS LIKELY WE
WILL SEE SOME SHOWER ACTIVITY ACROSS THE AREA ON FRIDAY. IF THE
ECMWF SOLUTION TURNS OUT TO BE CORRECT POPS WILL LIKELY NEED TO
BE RAISED QUITE A BIT BUT FOR NOW GIVEN LACK OF AGREEMENT WONT GO
TOO ROBUST WITH RAIN CHANCES.
AFTER THIS SYSTEM PUSHES AWAY FROM THE AREA...YET ANOTHER SOUTHERN
STREAM SYSTEM LOOKS TO APPROACH THE STATE OVER THE WEEKEND WITH
ANOTHER DECENT OPPORTUNITY FOR RAINFALL. COOLER AND DRIER AIR LOOKS
TO MOVE IN BEHIND THIS SYSTEM HOWEVER. THIS AIRMASS LOOKS SIMILAR TO
THE ONE THAT JUST MOVED IN A FEW DAYS AGO SO HIGHS WILL LIKELY TOP
OUT IN THE 60S ACROSS THE AREA TO START NEXT WEEK WITH LOWS IN THE
40S AND 50S.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS WEST-CENTRAL AND SOUTHWEST
FLORIDA THROUGH THE EVENING HOURS. THE MAIN AVIATION CONCERN WILL
BE CONTINUED GUSTY NORTHEASTERLY WINDS FOR THE NEXT SEVERAL HOURS
WHICH WILL GUST AT TIMES IN EXCESS OF 20 KNOTS. THE WIND WILL
BECOME LESS GUSTY WITH THE SETTING OF THE SUN THIS
EVENING...ESPECIALLY AWAY FROM THE IMMEDIATE COAST. MORE IN THE
WAY OF CLOUDS FOR WEDNESDAY WITH A FEW SHOWERS POSSIBLE FROM KPGD
TO KFMY/KRSW...HOWEVER ANTICIPATING VFR THROUGH END OF TAF PERIOD.
&&
.MARINE...
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 AM EST WEDNESDAY FOR
OFFSHORE WATERS FROM 20 TO 60 NM EXTENDING FROM BONITA BEACH TO
THE SUWANNEE RIVER...
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 AM EST WEDNESDAY FOR
NEAR SHORE WATERS OUT TO 20 NM EXTENDING FROM TARPON SPRINGS TO
THE SUWANNEE RIVER...
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 4 AM EST WEDNESDAY FOR
NEAR SHORE WATERS OUT TO 20 NM EXTENDING FROM BONITA BEACH TO THE
TARPON SPRINGS...THE WATERS OF TAMPA BAY...AND CHARLOTTE
HARBOR...
STRONG HIGH PRESSURE WILL REMAIN CENTERED TO THE NORTH OF THE
REGION THROUGH WEDNESDAY. ELEVATED NORTHEASTERLY WINDS AND
ELEVATED SEAS WILL KEEP CONDITIONS AT OR NEAR ADVISORY LEVELS
THROUGH TONIGHT. WINDS AND SEAS ARE EXPECTED TO RELAX BELOW
HEADLINE CRITERIA LATER IN THE WEEK...BUT AT THE SAME TIME...RAIN
CHANCES WILL BE INCREASING AS THE NEXT IN A SERIES OF SYSTEM
APPROACH FROM THE WEST BY FRIDAY.
&&
.FIRE WEATHER...
AFTER A BRIEF PERIOD OF DRY LOW LEVEL AIR...MOISTURE LEVELS ARE
ALREADY ON THE INCREASE...AND WILL CONTINUE TO INCREASE THROUGH
THE MID-WEEK PERIOD. RELATIVE HUMIDITY IS NOT EXPECTED TO DROP
BELOW CRITICAL LEVELS AGAIN DURING THE FORECAST PERIOD. WINDS
WILL HOWEVER REMAIN GUSTY THROUGH WEDNESDAY WITH ELEVATED
DISPERSION INDICES LATE WEDNESDAY MORNING AND WEDNESDAY
AFTERNOON.
FOG POTENTIAL...NO SIGNIFICANT AREA OF FOG OR REDUCED VISIBILITY
ARE EXPECTED THROUGH WEDNESDAY NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 54 73 58 76 / 0 10 10 10
FMY 59 75 59 78 / 10 30 10 0
GIF 55 73 56 76 / 10 20 20 10
SRQ 56 74 58 75 / 0 10 10 0
BKV 50 71 53 75 / 10 10 10 10
SPG 57 73 60 74 / 0 10 10 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...SMALL CRAFT ADVISORY UNTIL 10 AM EST WEDNESDAY FOR COASTAL
WATERS FROM TARPON SPRINGS TO SUWANNEE RIVER FL OUT
20 NM-WATERS FROM BONITA BEACH TO ENGLEWOOD FL OUT 20
TO 60 NM-WATERS FROM ENGLEWOOD TO TARPON SPRINGS FL
OUT 20 TO 60 NM-WATERS FROM TARPON SPRINGS TO
SUWANNEE RIVER FL OUT 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM EST WEDNESDAY FOR
CHARLOTTE HARBOR AND PINE ISLAND SOUND-COASTAL WATERS
FROM BONITA BEACH TO ENGLEWOOD FL OUT 20 NM-COASTAL
WATERS FROM ENGLEWOOD TO TARPON SPRINGS FL OUT 20 NM-
TAMPA BAY WATERS.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX..MROCZKA
LONG TERM/DECISION SUPPORT...MCKAUGHAN
AREA FORECAST DISCUSSION
NWS MIAMI FL
122 PM EST TUE JAN 5 2016
.AVIATION...
...18Z TAF ISSUANCE...VFR CONDITIONS ARE FORECAST TO PREVAIL
THROUGH AT LEAST 06Z EXCEPT FOR A SLIM CHC OF PERIODS OF MVFR
CEILINGS MAINLY ALONG THE SE FL COAST. WITH A BROAD SURFACE LOW
OVER EASTERN CUBA AND CENTRAL BAHAMAS AND A RIDGE OF HIGH PRESSURE
OVER THE CENTRAL ATLANTIC TO FLORIDA PENINSULA...THE PRESSURE
GRADIENT OF 5MB EXIST FROM CENTRAL FLORIDA TO THE KEYS WILL
SUPPORT NORTHEAST SUSTAINED FLOW OF 12 TO 18 KNOTS WITH GUSTS
THROUGH 18Z WEDNESDAY...WIND SPEEDS NOT AS STRONG TERMINAL
APF...TMB AND OPF. MOISTURE WILL INCREASE WITH DISTURBANCE
APPROACHING FROM THE WEST. AS A RESULT...RAIN IS EXPECTED MAINLY
AFTER 12Z WEDNESDAY SOME MVFR VISIBILITY RESTRICTIONS ARE POSSIBLE
AFTER 12Z WEDNESDAY...LESS CHANCE OF RAIN FOR TERMINAL KAPF.
&&
.PREV DISCUSSION... /ISSUED 839 AM EST TUE JAN 5 2016/
UPDATE...
NE WIND SHIFT GRADUALLY SPREADING SOUTHEASTWARD ACROSS EAST COAST
AREAS THIS MRNG. ONCE WINDS SHIFT TO NE...TEMPERATURES WILL RISE
AROUND 10 DEGREES /FROM L60S TO L70S/...THEN LEVEL OFF THROUGH
MUCH OF THE DAY AS SHOWER COVERAGE GRADUALLY INCREASES. WILL BE
MONITORING RADAR TRENDS CLOSELY...FOR POSSIBLE NEED TO BOOST POPS
UP A BIT. FOR NOW...NO CHANGES WARRANTED.
PREV DISCUSSION... /ISSUED 653 AM EST TUE JAN 5 2016/
AVIATION...
VFR CONDITIONS ARE FORECAST TO PREVAIL THROUGH THE
FORECAST PERIOD EXCEPT FOR A SLIM CHC OF PERIODS OF MVFR CEILINGS
MAINLY ALONG THE SE FL COAST. BUT GIVEN CONFIDENCE ON THAT IS LOW IT
IS NOT CURRENTLY REFLECTED ON THE FORECAST AND WILL AMEND AS NEEDED
IF THIS BECOMES A CONCERN OR ADDRESS IN FUTURE UPDATES. SOMETHING
NOT PICKED UP BY SHORT TERM MOS GUIDANCE BUT PICKED UP BY HRRR AND A
COUPLE OF LOCAL MODEL RUNS IS A LAND BREEZE PARTICULARLY ALONG SE
COAST SITES FROM FLL NORTH THROUGH AROUND DAWN WHEN THE LOW LEVEL NE
FLOW KICKS IN. THIS IS IN LINE WITH CURRENT OBSERVATIONS SO
REFLECTED THE LAND BREEZE ON TAF FORECAST FOR SITES ALONG SE COAST
THE FIRST COUPLE OF HOURS OR SO OF THE FORECAST EARLY THIS MORNING.
BLUSTERY NE WINDS WILL DEVELOP BY MID TO LATE MORNING AT ALL SITES
AND CONTINUE INTO THE EVENING. SOME MOISTURE WILL STREAM NORTH FROM
THE SOUTH TODAY WARRANTING MENTION OF VCSH PARTICULARLY ALONG SE FL
SITES.
PREV DISCUSSION... /ISSUED 441 AM EST TUE JAN 5 2016/
DISCUSSION...
TODAY-WEDNESDAY...COOL START TO THE DAY ACROSS SOUTH FLORIDA WITH
TEMPERATURES RANGING FROM THE UPPER 40S ACROSS GLADES AND HENDRY, TO
THE LOW 50S ALONG THE GULF COAST AND UPPER 50S TO LOW 60S ALONG THE
EAST COAST METRO.
FT LAUDERDALE INTERNATIONAL HAS DROPPED TO 59F SO FAR THIS MORNING,
BREAKING THE OLD RECORD FOR LATEST BELOW 60F TEMP WHICH WAS
PREVIOUSLY 29 DEC 1986. MIAMI INTERNATIONAL CONTINUES TO HOVER
AROUND 60-61F, SO IT MAY ALSO DIP TO 59F OR BELOW THIS MORNING. THE
PREVIOUS RECORD FOR LATEST BELOW 60F TEMP AT MIAMI WAS 23 DEC 1994.
WEST PALM DIPPED TO 57F YESTERDAY MORNING ALSO SETTING A NEW RECORD
FOR LATEST BELOW 60F DAY.
RADAR ALREADY SHOWS LIGHT ECHOES OVER THE ATLANTIC AND EAST COAST,
THOUGH A LOT OF THIS IS LIKELY NOT YET REACHING THE GROUND. DEEPER
MOISTURE ASSOCIATED WITH THE FORMER BOUNDARY LIFTS BACK TO THE NORTH
AS ANOTHER SHORTWAVE SWINGS INTO THE STATE AND SPAWNS A WEAK AREA OF
LOW PRESSURE ALONG THE BOUNDARY OVER THE CENTRAL/NW BAHAMAS. RAIN
CHANCES WILL INCREASE ALONG THE EAST COAST AND FAR SOUTHERN
PENINSULA LATE THIS MORNING AS THIS MOISTURE COMES INTO THE REGION
ALONG WITH THE FORCING AHEAD OF THE TROUGH .
HOW MUCH RAIN WE SEE TONIGHT INTO WEDNESDAY WILL BE DEPENDENT ON
WHERE THE LOW ULTIMATELY FORMS AND WHERE BEST CONVERGENT BANDS END
UP. BUT IT LOOKS LIKE A WET PERIOD THROUGH WEDNESDAY AS THE STATE
ALSO WILL BE IN A FAVORABLE REGION BETWEEN THE DEPARTING AND
APPROACHING JETS. WILL HAVE TO MONITOR FOR A LOCALIZED POTENTIAL
FOCUS FOR HEAVY RAINFALL ALONG THE EAST COAST. COVERAGE AND
INTENSITY OF RAIN WILL DROP OFF INTO THE INTERIOR AND GULF COAST.
A FEW THUNDERSTORMS ARE POSSIBLE, MAINLY OVER THE GULF STREAM
STARTING LATE TONIGHT, WITH THE POSSIBILITY FOR A FEW CREEPING INTO
THE EAST COAST.
TEMPERATURES WILL REMAIN COOL TODAY IN THE LOW 70S WITH A FEW MID
70S POSSIBLE INTO WEDNESDAY ALONG THE EAST COAST AS EAST FLOW
COMPONENT INCREASES OF THE RELATIVELY WARM ATLANTIC WATERS. THIS
MORNING WILL BE THE COOLEST OF THE WEEK WITH TEMPERATURES
ONLY DROPPING INTO UPPER 50S-MID 60S THE NEXT TWO NIGHTS.
INCREASING ONSHORE WINDS ALONG THE ATLANTIC COAST WILL RESULT IN RIP
CURRENT FORMATION AT THE ATLANTIC BEACHES TUE-WED...AND A HIGH RISK
OF RIP CURRENTS IS FORECAST.
THURSDAY-WEEKEND...THE PROGRESSIVE AND UNSETTLED PATTERN CONTINUES
INTO THE UPCOMING WEEKEND AS THE JET STREAM REMAINS ACROSS THE
SOUTHERN TIER OF THE US.
UPPER LEVEL SHORTWAVE AND ASSOCIATED DEVELOPING SURFACE LOW OVER THE
BAHAMAS QUICKLY LIFT OUT TO THE NORTHEAST ON THURS, BRINGING IN A
BRIEF SHOT OF DRIER AIR AND LOW RAIN CHANCES.
THEN THE NEXT SHORTWAVE CROSSING THE SOUTHEASTERN US BRINGS A WEAK
SURFACE FRONT INTO THE STATE ALONG WITH A RETURN OF ADEQUATE, THOUGH
NOT VERY DEEP, MOISTURE. SCATTERED SHOWERS WILL BE IN THE FORECAST
ACROSS THE REGION FOR BOTH FRI AND SAT.
WHILE BOTH THE GFS AND ECMWF ARE IN REMARKABLY GOOD AGREEMENT FOR
THE LATE WEEKEND, THERE ARE SOME SLIGHT DIFFERENCES IN THE SURFACE
PATTERN. THE ECMWF IS A LITTLE STRONGER AND SLOWER WITH THE
REINFORCING FRONT THAN THE GFS AND DRIES THINGS OUT A LITTLE MORE
INTO MONDAY. OVERALL HOWEVER, BOTH SHOW SAT NIGHT INTO SUNDAY AS A
PERIOD OF ENHANCED PRECIP CHANCES THAT MAY LINGER INTO MONDAY FOR AT
LEAST THE SOUTHERN PARTS OF THE REGION.
TEMPS/HUMIDITY WILL MODERATE MID-LATE WEEK...INTO THE UPPER
70S/AROUND 80 FOR HIGHS AND 60S FOR LOWS. THIS WILL BE ABOVE NORMAL,
BUT NOWHERE NEAR THE WARMTH OF LATE DEC.
MARINE...
STRONG EAST-NORTHEAST WINDS 20-25KTS CONTINUE ACROSS BOTH GULF AND
ATLANTIC WATERS INTO WEDNESDAY. SEAS BUILD TO 4-6FT FOR THE OFFSHORE
GULF WATERS AND 9-11FT IN THE GULF STREAM LATER TODAY. HAVE EXTENDED
THE SMALL CRAFT ADVISORY FOR ALL THE WATERS, INCLUDING LAKE
OKEECHOBEE, THROUGH WEDNESDAY MORNING. HAZARDOUS CONDITIONS MAY
LINGER LONGER OVER THE ATLANTIC INTO LATE WEDNESDAY.
WINDS DIMINISH WED NIGHT AS AN AREA OF LOW PRESSURE DEVELOPS JUST TO
OUR SOUTHEAST AND DISRUPTS THE GRADIENT. WINDS BECOME LIGHT NW
BEHIND THE DEPARTING LOW INTO THURS AND THEN S-SW AHEAD OF ANOTHER
SYSTEM INTO FRI. SEAS WILL BE SLOWER TO SUBSIDE, AND HAZARDOUS SEAS
MAY LINGER IN THE GULF STREAM THROUGH FRI.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 74 69 76 65 / 30 40 70 50
FORT LAUDERDALE 73 66 75 67 / 40 50 80 50
MIAMI 75 67 76 67 / 40 60 80 40
NAPLES 76 59 79 60 / 10 20 60 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH WEDNESDAY EVENING FOR FLZ168-172-
173.
AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST WEDNESDAY FOR AMZ610-630-
650-651-670-671.
GM...SMALL CRAFT ADVISORY UNTIL 10 AM EST WEDNESDAY FOR GMZ656-657-
676.
&&
$$
SHORT TERM...
LONG TERM....
AVIATION...
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1207 PM EST TUE JAN 5 2016
.UPDATE (REST OF TODAY THROUGH WEDNESDAY)...
17Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A CURRENTLY LESS
AMPLIFIED UPPER LEVEL PATTERN ACROSS THE CONUS. MAIN EAST COAST
LONGWAVE TROUGH IS QUICKLY EXITING THE NORTHEAST COAST INTO THE
WESTERN ATLANTIC...WITH A BROAD REGION OF UPPER RIDGING SPRAWLING
ACROSS THE EASTERN CONUS IN ITS WAKE. OUR FORECAST AREA RESIDES
WITHIN A DEEP LAYER OF MID/UPPER LEVEL SOUTHWESTERLY WINDS
UNDERNEATH THE SOUTHERN STREAM FLOW. WITHIN THIS SOUTHERN STREAM
WE ARE WATCHING A HEALTHY SHORTWAVE TROUGH EJECTING FROM NORTHERN
MEXICO OUT ACROSS THE WESTERN GULF OF MEXICO. WV IMAGERY SHOWS AN
INCREASING PLUME OF MID/HIGH LEVEL MOISTURE BEGINNING TO STREAM
OUT AHEAD OF THIS ENERGY OVER THE FLORIDA PENINSULA. THIS
SHORTWAVE WILL ACTUALLY BECOME BETTER ORGANIZED AS IT CROSSES THE
GULF DURING THE NEXT 12-18 HOURS...AND WILL CAUSE OUR FORECAST TO
BECOME A BIT TRICKY LATE TONIGHT INTO WEDNESDAY...ESPECIALLY THE
FURTHER SOUTH AND SOUTHEAST FROM THE I-4 CORRIDOR ONE TRAVELS.
AT THE SURFACE...OUR WEATHER IS DOMINATED BY STRONG HIGH PRESSURE
CENTERED OVER THE MID-ATLANTIC STATES...BUT RIDGING ALL THE WAY
SOUTH TO THE FL PENINSULA/EASTERN GULF OF MEXICO. THE TIGHT
GRADIENT ON THE SOUTHERN PERIPHERY OF THIS RIDGE ALONG WITH
RESIDUAL COLD AIR ADVECTION (CAA) HAS THE WINDS REALLY RAMPED UP
OVER THE EASTERN GULF OF MEXICO...WHERE SMALL CRAFT ADVISORIES
REMAIN IN EFFECT.
THE TROP DRIED OUT SIGNIFICANTLY DURING THE PAST 24 HOURS...WITH
THE 12Z KTBW SOUNDING SAMPLING A PW VALUE OF ONLY 0.44". THIS
VALUE IS RIGHT ABOUT AT THE 10TH PERCENTILE FOR EARLY JANUARY.
HOWEVER...THE DRYING IS OVER...AND NOW WE BEGIN A GRADUAL
MOISTENING OF THE COLUMN ONCE AGAIN FROM SOUTH TO NORTH. ALREADY
SEEING THE INCREASE IN HIGH LEVEL CIRRUS STREAMING OVER THE
REGION...BUT ALSO QUICKLY SEEING LOW LEVEL MOISTURE ADVECTING
NORTHWARD FROM SOUTH FLORIDA INTO OUR SOUTHERN ZONES. CROSS
SECTION ANALYSIS FROM ALL AVAILABLE GUIDANCE SHOW THIS GENERAL
ERODING OF THE DRIER LAYER ABOVE THE SURFACE...WITH THE PROCESS
QUICKEST AND MOST DRAMATIC OVER THE SOUTHERN HALF OF THE
PENINSULA.
AT LEAST THROUGH THE EVENING HOURS...THE DRY AIR WILL WIN OUT OVER
OUR ZONES AND HAVE NO RAIN MENTIONED IN THE FORECAST. LIKELY TO
SEE SOME SHOWERS DEVELOPING WITH THE MORE FAVORABLE MOISTURE
PROFILES AND ONSHORE FLOW ALONG THE FLORIDA EAST COAST...BUT WILL
BE TOUGH TO GET ANY MEASURABLE PRECIP INLAND ENOUGH TO REACH OUR
ZONES. THE TIGHT GRADIENT WILL KEEP CONDITIONS RATHER BREEZY
THROUGH THE AFTERNOON HOURS WITH SEASONABLY COOL TEMPERATURES
STILL IN PLACE. HIGH TEMPS THIS AFTERNOON RANGING FROM AROUND 60
FAR NORTH TO THE MIDDLE 60S I-4 CORRIDOR...AND WITHIN A COUPLE
DEGREES OF 70 OVER THE SOUTHERN ZONES.
LATER TONIGHT INTO WEDNESDAY IS WHEN THE FORECAST STARTS TO BECOME
A LITTLE MORE TRICKY. ALTHOUGH...THE GOOD NEWS IS THAT THE 12Z
NAM HAS COME AROUND CLOSER TO RECENT GFS/ECMWF SOLUTIONS COMPARED
TO ITS PREVIOUS 06Z RUN...WHICH WAS CONSIDERABLY WETTER FOR
WEDNESDAY SOUTH OF THE I-4 CORRIDOR. SOME FORECAST CONFIDENCE
ADDED THERE.
SHORTWAVE ENERGY WILL BE MIGRATING TOWARD THE REGION
OVERNIGHT/EARLY WEDNESDAY WITH INCREASING SYNOPTIC SUPPORT/DEEP
LAYER Q-VECTOR CONVERGENCE OVERSPREADING THE REGION IN ADVANCE.
RATHER IMPRESSIVE COUPLING OF LEFT EXIT REGION AND RIGHT ENTRANCE
REGION OF PAIRED UPPER JETS WILL ALSO BE TAKING PLACE. WHILE THE
DEEP LAYER HEIGHT FALLS/Q-VECTOR CONVERGENCE IS BROAD ENOUGH TO
ENCOMPASS MUCH OF THE REGION...THE BEST JET COUPLING AND
RESULTING UPPER DIVERGENCE FIELDS COINCIDENT WITH THE HEIGHT
FALLS ARE SHOWN TO MAXIMIZE OVER THE SOUTHERN FL PENINSULA/FLORIDA
STRAITS AND BAHAMAS. IT WILL BE THIS AREA WHERE IT IS AGREED UPON
IN THE NWP GUIDANCE THAT WE WILL SEE SURFACE CYCLOGENESIS COMMENCE
OVERNIGHT AND LIFT NORTHEASTWARD WEDNESDAY AND WEDNESDAY NIGHT.
WITH THE LOW DEVELOPING IN THIS AREA...THE STRONGEST AND MOST
EFFICIENT LOWER LEVEL FRONTOGENESIS ALSO STAYS JUST TO THE SOUTH
AND SOUTHEAST OF OUR ZONES. AT LEAST IN THE LOWER LEVELS...THIS
PLACEMENT WOULD RESULT IN OUR SOUTHERN ZONES RESIDING WITH A ZONE
OF GENERAL SUPPRESSION (DESCENDING AIR) ON THE COLD SIDE OF THE
FRONTS THERMAL CIRCULATION.
ALL THIS BEGIN SAID...WILL BE A VERY CLOSE CALL BETWEEN OUR FAR
SOUTHERN AND INTERIOR SOUTHERN ZONES
(HIGHLANDS/DESOTO/CHARLOTTE/LEE) AND THE NORTHERN EXTENT OF THE
POTENTIALLY ORGANIZED RAINFALL ZONE LATE TONIGHT INTO WEDNESDAY.
AS MENTIONED ABOVE...THE GFS/ECMWF HAVE BEEN CONSISTENT IN KEEPING
THE BEST LIFT AND MOST ORGANIZED SHOWER ACTIVITY GENERALLY OUT OF
OUR AREA FOR SEVERAL MODEL RUNS. THE NAM WHILE STILL FURTHER WEST
AND NORTHWEST WITH ITS LIFT AND RESULTING QPF FIELDS...HAS TRENDED
BACK FROM EARLIER SOLUTIONS. THIS GIVES SOME CONFIDENCE IN LESS
OVERALL SHOWER ACTIVITY AND RAINFALL AMOUNTS FROM HIGHLANDS COUNTY
TO LEE COUNTY...AND ESPECIALLY FURTHER NORTH AND NORTHWEST. WILL
HAVE TO KEEP SOME SHOWER CHANCES IN THE FORECAST BASED ON THE
INCREASINGLY FAVORABLE MOISTURE PROFILES...AND OVERALL PRESENCE OF
SYNOPTIC LIFT...BUT FEELING IS THAT A WASHOUT FOR THESE SOUTHERN
ZONES...WEDNESDAY WILL NOT BE. FURTHER NORTH TOWARD TAMPA BAY AND
NATURE COAST ZONES...JUST MENTIONING A FEW SPRINKLES ON WEDNESDAY.
MANY LOCATIONS ALONG AND NORTH OF THE I-4 CORRIDOR ARE LIKELY TO
NOT EVEN SEE MEASURABLE PRECIP.
GIVEN THE SYSTEM PASSING OVERHEAD...WILL SEE A MOSTLY CLOUDY DAY
FOR MOST ON WEDNESDAY...HOWEVER HIGH TEMPERATURES SHOULD BE UP
SEVERAL DEGREES FROM WHAT WE ARE SEEING THIS AFTERNOON.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL ACROSS WEST-CENTRAL AND SOUTHWEST
FLORIDA FOR THE REMAINDER OF THE DAY. THE MAIN AVIATION CONCERN
WILL BE GUSTY NORTHEASTERLY WINDS WHICH WILL GUST IN EXCESS OF 20
KNOTS AT TIMES. THE WIND WILL BECOME LESS GUSTY WITH THE SETTING
OF THE SUN THIS EVENING...ESPECIALLY AWAY FROM THE IMMEDIATE
COAST.
&&
.MARINE...
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 AM EST WEDNESDAY FOR
OFFSHORE WATERS FROM 20 TO 60 NM EXTENDING FROM BONITA BEACH TO
THE SUWANNEE RIVER...
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 4 AM EST WEDNESDAY FOR
NEAR SHORE WATERS OUT TO 20 NM EXTENDING FROM BONITA BEACH TO THE
SUWANNEE RIVER...
...SMALL CRAFT ADVISORY IN EFFECT UNTIL 4 PM EST THIS AFTERNOON
FOR THE WATERS OF TAMPA BAY AND CHARLOTTE HARBOR...
STRONG HIGH PRESSURE WILL REMAIN CENTERED TO THE NORTH OF THE
REGION THROUGH WEDNESDAY. ELEVATED NORTHEASTERLY WINDS AND
ELEVATED SEAS WILL KEEP CONDITIONS AT OR NEAR ADVISORY LEVELS
THROUGH TONIGHT. THE GRADIENT IS EXPECTED TO RELAX MID TO LATE
WEEK ALLOWING WINDS AND SEAS TO SUBSIDE.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 69 54 72 57 / 0 10 10 10
FMY 72 58 74 59 / 10 10 30 20
GIF 67 54 71 55 / 10 10 20 20
SRQ 71 56 74 58 / 10 10 10 10
BKV 65 49 71 52 / 0 10 10 10
SPG 67 56 70 59 / 0 10 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...SMALL CRAFT ADVISORY UNTIL 10 AM EST WEDNESDAY FOR WATERS
FROM BONITA BEACH TO ENGLEWOOD FL OUT 20 TO 60 NM-
WATERS FROM ENGLEWOOD TO TARPON SPRINGS FL OUT 20 TO
60 NM-WATERS FROM TARPON SPRINGS TO SUWANNEE RIVER FL
OUT 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM EST WEDNESDAY FOR COASTAL
WATERS FROM BONITA BEACH TO ENGLEWOOD FL OUT 20 NM-
COASTAL WATERS FROM ENGLEWOOD TO TARPON SPRINGS FL
OUT 20 NM-COASTAL WATERS FROM TARPON SPRINGS TO
SUWANNEE RIVER FL OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
CHARLOTTE HARBOR AND PINE ISLAND SOUND-TAMPA BAY
WATERS.
&&
$$
UPDATE/AVIATION/MARINE...MROCZKA
DECISION SUPPORT SERVICES...MCKAUGHAN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
337 PM EST TUE JAN 5 2016
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 319 PM EST TUE JAN 5 2016
WV IMAGERY AND RAP ANALYSIS INDICATED MID/UPPER LEVEL RIDGING FROM
THE UPPER MS VALLEY INTO THE GREAT LAKES. AT THE SFC...A TIGHT PRES
GRADIENT AND STRONG SW FLOW PREVAILED OVER LAKE SUPERIOR AND UPPER
MI BTWN HIGH PRES OVER THE ERN LAKES AND FRONT/TROUGH FROM NW
ONTARIO INTO THE NRN PLAINS. SW GUSTS TODAY HAVE REACHED OVER 30 MPH
AT SOME LOCATIONS...ESPECIALLY EAST HALF AND ALONG DOWNSLOPING AREAS
ALONG LAKE SUPERIOR. MOISTENING WITH THE SW WIND ACROSS LAKE MI HAS
BROUGHT LOW CLOUDS INTO FAR ERN UPPER MI...S AND E FROM ISQ TO ERY.
THE PATCH OF LOW CLOUDS OVER NCNTRL WI AND SW UPPER MI FROM THIS
MORNING HAS DISSIPATED WITH DAYTIME MIXING.
TONIGHT...A SHORTWAVE TROUGH MOVING THROUGH NRN ONTARIO WILL HELP
DRAG A WEAK SFC TROUGH/COLD FRONT INTO LAKE SUPERIOR. 850-800 MB
FGEN ASSOCIATED WITH THE FRONT ALONG WITH WEAK ISENTROPIC LIFT ON
295K SFC AND MOISTENING FROM WSW WINDS ACROSS LAKE SUPERIOR WILL
SUPPORT A SLIGHT CHANCE FOR LIGHT SNOW SHOWERS OR FLURRIES INTO THE
KEWEENAW. WITH THE MOIST LAYER ONLY TO AROUND -10C...SOME FZDZ MAY
ALSO BE POSSIBLE LATE TONIGHT INTO WED MORNING.
WEDNESDAY...MAY SEE A FEW LIGHT LES SHOWERS OVER THE NRN PORTIONS OF
THE KEWEENAW WED MORNING WITH SW WINDS AND 850MB TEMPS TO AROUND
-10C...BUT NOT SIGNIFICANT ACCUMULATIONS. A TROUGH WILL MOVE OVER
THE WRN FCST AREA AND OVER LAKE SUPERIOR IN THE AFTERNOON.
DEVELOPMENT OF 800-700 MB FGEN FORCING WILL PROMOTE AN ELONGATED
AREA OF LIGHT SNOW OVER MAINLY WRN/NWRN UPPER MI WED AFTERNOON.
MODEL CONSENSUS QPF SUGGESTS SNOW ACCUMS WOULD BE HALF AN INCH OR
LESS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 336 PM EST TUE JAN 5 2016
THE SECOND HALF OF THIS WORK WEEK WILL SEE MORE MODERATE
TEMPERATURES AND PERIODS OF LIGHT SNOW...BEFORE MUCH COLDER...ARCTIC
AIR ARRIVES FOR THE SECOND HALF OF THE WEEKEND. THAT ARCTIC AIR WILL
PRODUCE THE COLDEST TEMPERATURES OF THE WINTER THUS FAR AND PERIODS
OF LAKE EFFECT SNOW.
PRECIPITATION SHOULD MOVE INTO THE WESTERN U.P. WEDNESDAY
AFTERNOON/EVENING ALONG THE STALLED TROUGH OVER WESTERN LAKE
SUPERIOR AND ASSOCIATED WITH INCREASING MOISTURE AND MID LEVEL
Q-VECTOR CONVERGENCE WITH THE SHORTWAVE LIFTING NORTHEAST OUT OF
THE CENTRAL PLAINS. WILL LIKELY SEE TWO WAVES...WITH THE FIRST AN
ELONGATED WSW TO ENE AREA OF SNOW STRETCHING ACROSS THE WESTERN
HALF OF THE U.P. AND ASSOCIATED WITH 900-750MB FGEN FORCING. THE
SECOND PUSH ARRIVES LATE WEDNESDAY NIGHT INTO THURSDAY AS THE
SHORTWAVE AND 850-700MB WARM AIR ADVECTION PUSHES THROUGH. EXPECT
ALL OF THIS PRECIP TO FALL AS SNOW LATE WEDNESDAY AFTERNOON INTO
THURSDAY...BUT WITH MUCH OF THE FORCING BELOW THE DGZ...THINK
SNOW-TO-LIQUID RATIOS WILL BE RIGHT AROUND 10-1 FOR MUCH OF THE
EVENT. COMPARED TO YESTERDAY...ONLY SOME MINOR ADJUSTMENTS HAVE
BEEN MADE TO THE FORECAST AND IT STILL LOOKS LIKE 1-2 INCHES OF
SNOW OVER A 24HR PERIOD...WITH A FEW SLIGHTLY HIGHER AMOUNTS NEAR
IRONWOOD. WITH THE DEEP MOISTURE CUTTING OUT BEHIND THE SHORTWAVE
(ASSOCIATED WITH THE WEAK MID-LEVEL RIDGING)...THERE IS THE
POTENTIAL FOR SOME FREEZING DRIZZLE THURSDAY AFTERNOON AND
EVENING...BUT MODELS VARY ON THE AMOUNT OF LOW LEVEL MOISTURE (NAM
SHOWING ABUNDANT MOISTURE WHILE THE GFS AND OUR REGIONAL WRF
MAINTAIN A 2-3KFT STRATUS DECK. WILL LEAVE OUT FREEZING DRIZZLE FOR
NOW...BUT MAY NEED TO ADD IF THE MODELS TREND TOWARDS THE NAM.
THE NEXT WAVE OF LIGHT PRECIPITATION WILL MOVE NORTHEAST INTO THE
AREA FRIDAY INTO SATURDAY AS A WEAK LOW LIFTS FROM MISSOURI AT 12Z
FRIDAY TO JAMES BAY BY 12Z SUNDAY. AT THIS POINT...IT LOOKS LIKE THE
BEST FORCING WILL BE OVER THE EASTERN U.P. WITH THE BEST PUSH OF
SNOW MOVING THROUGH DURING THE DAY ON FRIDAY (GENERALLY 1-3 INCHES
OVER 18-24HRS). STILL LOOKS LIKE THERE WILL BE ENOUGH LOW LEVEL
WARMING TO RAISE WETBULB0 HEIGHTS TO LEAD TO A LITTLE BIT OF RAIN
MIXING IN WITH THE SNOW ALONG THE BAY OF GREEN BAY SHORELINE IN
MENOMINEE COUNTY AND WILL CONTINUE TO INCLUDE A SLIGHT CHANCE TO
CHANCE OF RAIN THERE.
WHILE THE LOW IS FAIRLY WEAK AND BRINGS SOME LIGHT SNOW FRIDAY
INTO FRIDAY NIGHT...A STRONG WAVE FROM THE ARCTIC WILL BE DIVING
SOUTH ACROSS THE CANADIAN PRAIRIES AND BE MOVING TOWARDS THE GREAT
LAKES REGION FOR THE SECOND HALF OF THE WEEKEND AND FOR EARLY NEXT
WEEK. THAT WILL LEAD TO A SIGNIFICANT TRANSITION IN TEMPERATURES...
FROM THE LOWER 30S FOR THE LATER HALF OF THIS WEEK TO HIGHS IN THE
SINGLE DIGITS TO LOWER TEENS ABOVE ZERO ON MONDAY. THAT COLD AIR
(850MB TEMPS FALLING TO -20C ON SUNDAY EVENING AND -23C ON MONDAY)
WILL KICK THE LAKE EFFECT MACHINE BACK INTO GEAR FOR THE AREA...BUT
THE COLD TEMPERATURES WILL KEEP THE CLOUD GENERALLY ABOVE THE DGZ
LEADING TO SMALLER FLAKES. WHILE THAT WILL LIKELY KEEP SNOWFALL
AMOUNTS IN CHECK...THE HIGH INVERSION HEIGHTS (RISING TO 12KFT ON
SUNDAY WITH LK INDUCED CAPES NEARING 1000 J/KG) WOULD SUPPORT
STRONG BANDS THAT WOULD BE VERY EFFECTIVE AT REDUCING VISIBILITIES.
WHILE THERE IS STILL SOME UNCERTAINTY ON THE WIND FIELD (DUE TO
DIFFERENCES IN THE EVOLUTION OF A SECONDARY WAVE AND POSSIBLE LOW
MOVING UP THE EASTERN HALF OF THE CONUS)...WOULD EXPECT A GRADUAL
TRANSITION FROM NORTHWEST TO WEST-SOUTHWEST SUNDAY THROUGH TUESDAY.
FOLLOWED THAT IDEA FOR THE POPS AND WILL CONTINUE TO SHOW DEFINITE
POPS IN THE MOST FAVORED AREAS NEAR LAKE SUPERIOR. STILL WAY TO
EARLY FOR GETTING AN IDEA ON SNOW AMOUNTS...BUT WOULD EXPECT AT
LEAST SOME ADVISORY SNOWFALL AMOUNTS FOR THE NW TO WNW WIND AREAS.
WILL ADD A MENTION OF THE COLD AIR AND SNOW WITH REDUCED
VISIBILITIES TO THE HWO FOR AREAS NEAR LAKE SUPERIOR FOR THE SUNDAY
INTO MONDAY PERIOD.
DID LOWER HIGHS A FEW DEGREES OVER THE INTERIOR WEST FOR
MONDAY...AS RAW MODEL DATA CONTINUES TO INDICATE HIGHS STRUGGLING
TO REACH ZERO ALONG THE WISCONSIN BORDER. LOOKING BACK AT PAST DAYS
WITH HIGHS AT OR BELOW ZERO AT OUR OFFICE AND ALSO THE STAMBAUGH
COOP, THERE IS A CONSISTENT IDEA OF 850MB TEMPS BEING AROUND OR
BELOW -23C (WHICH IS SIMILAR TO THE 12Z GFS AND THE 12Z ECMWF IS
COLDER). WHILE THE 00Z ECMWF ENSEMBLE MEAN IS AROUND -17C...FELT
COMFORTABLE IN LOWERING HIGHS OUT WEST AND AWAY FROM LAKE SUPERIOR
CLOSER TO ZERO. IF THE COLD SIGNAL REMAINS...WILL LIKELY NEED TO
LOWER HIGHS A LITTLE FURTHER ON MONDAY. AT OUR OFFICE...THINK THE
MODERATION FROM LAKE SUPERIOR WILL HELP TO KEEP HIGHS IN THE MID TO
UPPER SINGLE DIGITS ABOVE ZERO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1241 PM EST TUE JAN 5 2016
EXPECT GUSTY SW WINDS FROM 20-25 KT THROUGH THE AFTERNOON AT TAF
SITES. EXPECT VFR CONDITIONS TO PREVAIL THROUGH TODAY...WITH
DOWNSLOPE NATURE OF THE SW FLOW HELPING TO MAINTAIN LOWER RH.
HOWEVER...GUIDANCE SUGGESTS LOW CLOUDS WILL ARRIVE TONIGHT...WITH
FCST MVFR CIGS TO ARRIVE OVERNIGHT. THE BEST CHANCE FOR IFR CIGS WILL
BE AT IWD OVERNIGHT. LIGHT IS ALSO POSSIBLE AT KCMX BY WED MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 319 PM EST TUE JAN 5 2016
A TIGHT PRES GRADIENT BTWN A DEPARTING HIGH PRES RIDGE AND LOW PRES
TROUGH FROM HUDSON BAY TO THE NRN PLAINS MAY STILL SUPPORT SW GALES
INTO ERN LAKE SUPERIOR THIS EVENING. OTHERWISE EXPECT GALES TO
DIMINISH TONIGHT AS GRADIENT GRADUALLY WEAKENS. WINDS WILL DIMINISH
FURTHER WED/THU TO MOSTLY UNDER 20KT AS A LOW PRES TROUGH SETTLES
OVER THE UPPER GREAT LAKES. WINDS WILL INCREASE AGAIN THIS WEEKEND
AS LOW PRES LIFTS NE INTO THE GREAT LAKES REGION AND CAA ENSUES IN
NW FLOW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ265>267.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LSZ243-244-263-264.
LAKE MICHIGAN...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
319 PM EST TUE JAN 5 2016
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 319 PM EST TUE JAN 5 2016
WV IMAGERY AND RAP ANALYSIS INDICATED MID/UPPER LEVEL RIDGING FROM
THE UPPER MS VALLEY INTO THE GREAT LAKES. AT THE SFC...A TIGHT PRES
GRADIENT AND STRONG SW FLOW PREVAILED OVER LAKE SUPERIOR AND UPPER
MI BTWN HIGH PRES OVER THE ERN LAKES AND FRONT/TROUGH FROM NW
ONTARIO INTO THE NRN PLAINS. SW GUSTS TODAY HAVE REACHED OVER 30 MPH
AT SOME LOCATIONS...ESPECIALLY EAST HALF AND ALONG DOWNSLOPING AREAS
ALONG LAKE SUPERIOR. MOISTENING WITH THE SW WIND ACROSS LAKE MI HAS
BROUGHT LOW CLOUDS INTO FAR ERN UPPER MI...S AND E FROM ISQ TO ERY.
THE PATCH OF LOW CLOUDS OVER NCNTRL WI AND SW UPPER MI FROM THIS
MORNING HAS DISSIPATED WITH DAYTIME MIXING.
TONIGHT...A SHORTWAVE TROUGH MOVING THROUGH NRN ONTARIO WILL HELP
DRAG A WEAK SFC TROUGH/COLD FRONT INTO LAKE SUPERIOR. 850-800 MB
FGEN ASSOCIATED WITH THE FRONT ALONG WITH WEAK ISENTROPIC LIFT ON
295K SFC AND MOISTENING FROM WSW WINDS ACROSS LAKE SUPERIOR WILL
SUPPORT A SLIGHT CHANCE FOR LIGHT SNOW SHOWERS OR FLURRIES INTO THE
KEWEENAW. WITH THE MOIST LAYER ONLY TO AROUND -10C...SOME FZDZ MAY
ALSO BE POSSIBLE LATE TONIGHT INTO WED MORNING.
WEDNESDAY...MAY SEE A FEW LIGHT LES SHOWERS OVER THE NRN PORTIONS OF
THE KEWEENAW WED MORNING WITH SW WINDS AND 850MB TEMPS TO AROUND
-10C...BUT NOT SIGNIFICANT ACCUMULATIONS. A TROUGH WILL MOVE OVER
THE WRN FCST AREA AND OVER LAKE SUPERIOR IN THE AFTERNOON.
DEVELOPMENT OF 800-700 MB FGEN FORCING WILL PROMOTE AN ELONGATED
AREA OF LIGHT SNOW OVER MAINLY WRN/NWRN UPPER MI WED AFTERNOON.
MODEL CONSENSUS QPF SUGGESTS SNOW ACCUMS WOULD BE HALF AN INCH OR
LESS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 306 AM EST TUE JAN 5 2016
MAY SEE A FEW LIGHT LES SHOWERS OVER THE NRN PORTIONS OF THE
KEWEENAW WED MORNING WITH SW WINDS AND 850MB TEMPS AROUND -9C...BUT
NOT SIGNIFICANT ACCUMULATIONS. A TROUGH AND SFC FRONT STALL OUT OVER
THE AREA ON WED AND STAY INTO THU NIGHT. DEVELOPMENT OF LOW-MID
LEVEL FGEN FORCING WILL PROMOTE AN ELONGATED AREA OF LIGHT SNOW OVER
MAINLY WRN/NWRN UPPER MI WED AFTERNOON AND EVENING. A SHORTWAVE AND
WAA WILL THEN LEAD TO WIDESPREAD LIGHT SNOW WED NIGHT INTO
THU...ENDING TIME UNCERTAIN WITH DIFFERING MODEL SOLUTIONS. EXPECT
SNOW TO LIQUID RATIOS AROUND 10 TO 1 GIVEN MOST OF THE WEAK LIFT IS
BELOW THE DGZ...WHICH WHEN COMBINED WITH TOTAL QPF AMOUNTS OF 0.10-
0.25 INCHES (LOWEST SE AND GREATEST OVER THE W AND NW) EXPECT
GENERALLY 1 TO JUST OVER 2 INCHES OF SNOW IN THE 24-30 HOUR PERIOD.
ANOTHER PERIOD OF LIGHT AND INSIGNIFICANT SNOW IS EXPECTED FRI AND
SAT AS A WEAK LOW MOVES FROM MO AT 12Z FRI TO QUEBEC OR JAMES BAY
(DEPENDING ON MODEL SOLUTION) BY 00Z SUN. STILL LOOKS LIKE BEST
FORCING/PRECIP WILL BE OVER THE ERN AND MAYBE SRN UPPER MI IN THE
FRI AFTERNOON/FRI NIGHT TIME FRAME. STILL SEEING MODEL DIFFERENCES
ON TIMING. COULD SEE SOME RAIN MIX IN FRI AFTERNOON OVER SERN UPPER
MI AS WET BULB ZERO HEIGHTS RISE WITH HIGHS IN THE MID 30S. OVERALL
ONLY EXPECTING A VERY MINOR 1-3 INCHES OF SNOW OVER 36 HOURS.
MAIN STORY IN THE LONG TERM IS THAT MODEL PERSIST IN SHOWING AN
ACTIVE WAVE MOVING INTO THE AREA SAT NIGHT AND DEEPENING INTO A
CLOSED UPPER LOW OVER OR NEAR THE CWA LATE SUN AND SUN NIGHT. 850MB
TEMPS AS LOW AS -25C ARE CO-LOCATED WITH THE LOW. MODELS ALSO
CONTINUE TO SHOW ANOTHER WAVE MOVING IN MID NEXT WEEK...WHICH WILL
REINFORCE THE COLD AIR. TEMPS WILL GO FROM HIGHS IN THE UPPER 20S TO
MID 30S AND LOWS IN THE 20S LATE IN THE WEEK TO HIGHS IN THE SINGLE
DIGITS TO TEENS ABOVE ZERO AND LOWS IN THE SINGLE DIGITS ABOVE AND
BELOW ZERO EARLY NEXT WEEK. NW-W WIND SNOWBELTS WILL CERTAINLY SEE
PERSISTENT LES SAT NIGHT THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...BUT NOT EXPECTING WARNING AMOUNTS AT THIS TIME DUE TO SMALL
FLAKE SIZE GIVEN VERY COLD TEMPS (CLOUD LAYER COLDER THAN THE
PREFERRED DGZ). THAT COLD AIR WILL ALSO MARK THE FIRST TIME OUR
OFFICE WILL FALL BELOW ZERO SINCE MARCH 28...2015. THROUGH JANUARY
3...THAT MAKES A 281 DAY STREAK AND IS CURRENTLY TIED FOR THE 16TH
LONGEST STREAK. IF THE CURRENT FORECAST HOLDS...WE WILL MAKE IT TO
AROUND 288 OR 289 DAYS...WHICH WOULD BE RIGHT AROUND THE 9TH LONGEST
STREAK OF TEMPERATURES AT OR ABOVE ZERO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1241 PM EST TUE JAN 5 2016
EXPECT GUSTY SW WINDS FROM 20-25 KT THROUGH THE AFTERNOON AT TAF
SITES. EXPECT VFR CONDITIONS TO PREVAIL THROUGH TODAY...WITH
DOWNSLOPE NATURE OF THE SW FLOW HELPING TO MAINTAIN LOWER RH.
HOWEVER...GUIDANCE SUGGESTS LOW CLOUDS WILL ARRIVE TONIGHT...WITH
FCST MVFR CIGS TO ARRIVE OVERNIGHT. THE BEST CHANCE FOR IFR CIGS WILL
BE AT IWD OVERNIGHT. LIGHT IS ALSO POSSIBLE AT KCMX BY WED MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 319 PM EST TUE JAN 5 2016
A TIGHT PRES GRADIENT BTWN A DEPARTING HIGH PRES RIDGE AND LOW PRES
TROUGH FROM HUDSON BAY TO THE NRN PLAINS MAY STILL SUPPORT SW GALES
INTO ERN LAKE SUPERIOR THIS EVENING. OTHERWISE EXPECT GALES TO
DIMINISH TONIGHT AS GRADIENT GRADUALLY WEAKENS. WINDS WILL DIMINISH
FURTHER WED/THU TO MOSTLY UNDER 20KT AS A LOW PRES TROUGH SETTLES
OVER THE UPPER GREAT LAKES. WINDS WILL INCREASE AGAIN THIS WEEKEND
AS LOW PRES LIFTS NE INTO THE GREAT LAKES REGION AND CAA ENSUES IN
NW FLOW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ265>267.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LSZ243-244-263-264.
LAKE MICHIGAN...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...VOSS
LONG TERM...TITUS
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1244 PM EST TUE JAN 5 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 455 AM EST TUE JAN 5 2016
WV IMAGERY AND RAP ANALYSIS INDICATED MID/UPPER LEVEL RIDGING FROM
THE UPPER MS VALLEY INTO THE WRN GREAT LAKES. AT THE SFC...A TIGHT
PRES GRADIENT AND STRONG SW FLOW PREVAILED OVER LAKE SUPERIOR AND
UPPER MI BTWN HIGH PRES OVER THE ERN LAKES AND FRONT/TROUGH FROM NW
ONTARIO INTO THE NRN PLAINS. MOISTENING WITH THE SW WIND ACROSS LAKE
MI HAS BROUGH LOW CLOUDS INTO FAR ERN UPPER MI...S AND E FROM ISQ TO
ERY. A BAND OF CLOUDS HAS ALSO DEVELOPED NE FROM THE BAY OF GREEN
BAY. UPSTREAM A LARGER AREA OF LOW CLOUDS FROM ERN MN AND FAR WRN WI
WAS GRADUALLY LIFTING TO THE NNE TO HYR-EAU.
TODAY...HIGH RES MODELS 925 MB RH FCSTS...IN LINE WITH CURRENT
TRENDS...SUGGEST THAT THE CLOUDS OVER NW WI WILL GRADUALLY SPREAD
INTO THE SW PORTION OF UPPER MI TODAY BUT THIN OUT OVER CNTRL
AREAS...ESPECIALLY WHERE DOWNSLOPE SW WINDS PREVAIL. THE CLOUDS OVER
THE ERN CWA ARE EXPECTED TO PUSH FARTHER TO THE EAST. EVEN WITH
LIMITED DAYTIME MIXING AS TEMPS CLIMB INTO THE UPPER 20S TO AROUND
30...WINDS WILL BECOME GUSTY TO AROUND 25-30 MPH.
TONIGHT...A SHORTWAVE TROUGH MOVING THROUGH NRN ONTARIO WILL HELP
DRAG A WEAK COLD FRONT INTO LAKE SUPERIOR. 850-700 MB FGEN
ASSOCIATED WITH THE FRONT ALONG WITH WEAK ISENTROPIC LIFT ALONG WITH
MOISTENING FROM WSW WINDS ACROSS LAKE SUPERIOR WILL SUPPORT A SLIGHT
CHANCE FOR LIGHT SNOW SHOWERS OR FLURRIES INTO THE KEWEENAW. WITH
THE MOIST LAYER ONLY TO AROUND -10C...SOME FZDZ MAY ALSO BE
POSSIBLE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 306 AM EST TUE JAN 5 2016
MAY SEE A FEW LIGHT LES SHOWERS OVER THE NRN PORTIONS OF THE
KEWEENAW WED MORNING WITH SW WINDS AND 850MB TEMPS AROUND -9C...BUT
NOT SIGNIFICANT ACCUMULATIONS. A TROUGH AND SFC FRONT STALL OUT OVER
THE AREA ON WED AND STAY INTO THU NIGHT. DEVELOPMENT OF LOW-MID
LEVEL FGEN FORCING WILL PROMOTE AN ELONGATED AREA OF LIGHT SNOW OVER
MAINLY WRN/NWRN UPPER MI WED AFTERNOON AND EVENING. A SHORTWAVE AND
WAA WILL THEN LEAD TO WIDESPREAD LIGHT SNOW WED NIGHT INTO
THU...ENDING TIME UNCERTAIN WITH DIFFERING MODEL SOLUTIONS. EXPECT
SNOW TO LIQUID RATIOS AROUND 10 TO 1 GIVEN MOST OF THE WEAK LIFT IS
BELOW THE DGZ...WHICH WHEN COMBINED WITH TOTAL QPF AMOUNTS OF 0.10-
0.25 INCHES (LOWEST SE AND GREATEST OVER THE W AND NW) EXPECT
GENERALLY 1 TO JUST OVER 2 INCHES OF SNOW IN THE 24-30 HOUR PERIOD.
ANOTHER PERIOD OF LIGHT AND INSIGNIFICANT SNOW IS EXPECTED FRI AND
SAT AS A WEAK LOW MOVES FROM MO AT 12Z FRI TO QUEBEC OR JAMES BAY
(DEPENDING ON MODEL SOLUTION) BY 00Z SUN. STILL LOOKS LIKE BEST
FORCING/PRECIP WILL BE OVER THE ERN AND MAYBE SRN UPPER MI IN THE
FRI AFTERNOON/FRI NIGHT TIME FRAME. STILL SEEING MODEL DIFFERENCES
ON TIMING. COULD SEE SOME RAIN MIX IN FRI AFTERNOON OVER SERN UPPER
MI AS WET BULB ZERO HEIGHTS RISE WITH HIGHS IN THE MID 30S. OVERALL
ONLY EXPECTING A VERY MINOR 1-3 INCHES OF SNOW OVER 36 HOURS.
MAIN STORY IN THE LONG TERM IS THAT MODEL PERSIST IN SHOWING AN
ACTIVE WAVE MOVING INTO THE AREA SAT NIGHT AND DEEPENING INTO A
CLOSED UPPER LOW OVER OR NEAR THE CWA LATE SUN AND SUN NIGHT. 850MB
TEMPS AS LOW AS -25C ARE CO-LOCATED WITH THE LOW. MODELS ALSO
CONTINUE TO SHOW ANOTHER WAVE MOVING IN MID NEXT WEEK...WHICH WILL
REINFORCE THE COLD AIR. TEMPS WILL GO FROM HIGHS IN THE UPPER 20S TO
MID 30S AND LOWS IN THE 20S LATE IN THE WEEK TO HIGHS IN THE SINGLE
DIGITS TO TEENS ABOVE ZERO AND LOWS IN THE SINGLE DIGITS ABOVE AND
BELOW ZERO EARLY NEXT WEEK. NW-W WIND SNOWBELTS WILL CERTAINLY SEE
PERSISTENT LES SAT NIGHT THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK...BUT NOT EXPECTING WARNING AMOUNTS AT THIS TIME DUE TO SMALL
FLAKE SIZE GIVEN VERY COLD TEMPS (CLOUD LAYER COLDER THAN THE
PREFERRED DGZ). THAT COLD AIR WILL ALSO MARK THE FIRST TIME OUR
OFFICE WILL FALL BELOW ZERO SINCE MARCH 28...2015. THROUGH JANUARY
3...THAT MAKES A 281 DAY STREAK AND IS CURRENTLY TIED FOR THE 16TH
LONGEST STREAK. IF THE CURRENT FORECAST HOLDS...WE WILL MAKE IT TO
AROUND 288 OR 289 DAYS...WHICH WOULD BE RIGHT AROUND THE 9TH LONGEST
STREAK OF TEMPERATURES AT OR ABOVE ZERO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1241 PM EST TUE JAN 5 2016
EXPECT GUSTY SW WINDS FROM 20-25 KT THROUGH THE AFTERNOON AT TAF
SITES. EXPECT VFR CONDITIONS TO PREVAIL THROUGH TODAY...WITH
DOWNSLOPE NATURE OF THE SW FLOW HELPING TO MAINTAIN LOWER RH.
HOWEVER...GUIDANCE SUGGESTS LOW CLOUDS WILL ARRIVE TONIGHT...WITH
FCST MVFR CIGS TO ARRIVE OVERNIGHT. THE BEST CHANCE FOR IFR CIGS WILL
BE AT IWD OVERNIGHT. LIGHT IS ALSO POSSIBLE AT KCMX BY WED MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 525 AM EST TUE JAN 5 2016
A TIGHT PRES GRADIENT BTWN A DEPARTING HIGH PRES RIDGE AND LOW PRES
TROUGH FROM HUDSON BAY TO THE NRN PLAINS WILL SUPPORT SW GALES
ACROSS LAKE SUPERIOR TODAY. THE GALES WILL BEGIN TO DIMINISH
TONIGHT. WINDS WILL DIMINISH FURTHER WED/THU TO MOSTLY UNDER 20KT AS
A LOW PRES TROUGH SETTLES OVER THE UPPER GREAT LAKES. WINDS WILL
INCREASE AGAIN FRI/SAT AS LOW PRES LIFTS NE INTO THE GREAT LAKES
REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LSZ265>267.
GALE WARNING UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR LSZ162.
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LSZ243-244-263-264.
LAKE MICHIGAN...
GALE WARNING UNTIL 1 AM EST WEDNESDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
416 PM CST TUE JAN 5 2016
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 416 PM CST TUE JAN 5 2016
SHORT WAVE IN NORTHERN NEW MEXICO IS SLATED TO MOVE NORTHEAST AND
STRENGTHEN SLIGHTLY...BRINGING SOME DECENT LIFT AND LIGHT SNOW
STARTING MIDDAY WEDNESDAY. THERE WILL BE A COUPLE SHALLOW LAYERS
ALOFT WITH TEMPS SLIGHTLY ABOVE FREEZING...LEADING TO SOME MIXED
PRECIPITATION EARLY ON...BUT THESE TEMPS ALOFT COOL AS THE SHORT
WAVE WAVE APPROACHES...SO LIGHT SNOW IS MOSTLY EXPECTED WEDNESDAY
AFTERNOON. PRECIP AMOUNTS THROUGH 36 HOURS LOOK TO BE AROUND 0.05
TO 0.15 INCH... RESULTING IN A BROAD AREA OF UP TO 2 INCHES SNOW
BEFORE IT TAPERS OFF LATE WEDNESDAY NIGHT. OTHERWISE...TEMPS WILL
REMAIN ABOVE NORMAL AND WINDS WILL DIMINISH EARLY THIS EVENING AS
GRADIENT RELAXES. FORTUNATELY IT LOOKS LIKE WINDS SHOULD REMAIN
STEADY ENOUGH TO PREVENT ANY RADIATIONAL FOG IN THOSE AREAS THAT
HAVE REMAINED CLEAR OR THAT CLEAR OUT LATE THIS AFTERNOON.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 416 PM CST TUE JAN 5 2016
VERY SIMILAR FORECAST IN THE EXTENDED RANGE WITH A PERIOD OF
SNOW...MIXED WITH FREEZING DRIZZLE OR DRIZZLE AT TIMES WEDNESDAY
NIGHT THRU FRIDAY NIGHT. THEN A PERIOD OF ARCTIC AIR AS SFC TEMPS
DROP BELOW FREEZING FOR THE FIRST TIME THIS WINTER SEASON.
WEDNESDAY NIGHT/THURSDAY CAN BE CHARACTERIZED AS A PERIOD OF
FREEZING DRIZZLE/DRIZZLE/FLURRIES OR LIGHT SNOW DEPENDING UPON IF
ANY ICE CRYSTALS FEED THE LOWER LEVELS OF THE ATMOSPHERE FROM THE
DEPARTING SYSTEM WEDNESDAY EVENING. LOW CLDS/FOG AND NEARLY STEADY
TEMPS WILL LEAD TO THIS TYPE OF SCENARIO WITH LITTLE CHANGE IN THE
AIR MASS. A SECONDARY SHORT WAVE WILL MOVE OUT OF THE SOUTHWEST
CONUS THURSDAY NIGHT AND PROVIDE ANOTHER PERIOD OF MAINLY LIGHT SNOW
FRIDAY/FRIDAY NIGHT. QPF AMTS AND SNOWFALL RATES WILL BE LOW WITH
BOTH WEDNESDAY AND FRIDAY SYSTEMS. THEREFORE...SNOWFALL AMTS FOR THE
WHOLE PERIOD MAY ADD UP TO 3-5 INCHES...ESPECIALLY IN SC/SE MN AND
INTO WC WI DEPENDING UPON THE TRACK OF THE UPPER LEVEL FEATURES.
ELSEWHERE...AMTS WILL BE LIMITED TO 1-2 INCHES OF SNOWFALL.
THE MAIN WX FEATURE IN THE EXTENDED PERIOD REMAINS THE ARCTIC AIR
MASS WHICH WILL LEAD TO OUR FIRST /ALL OF MPX CWA/ BELOW ZERO
READINGS SINCE LAST WINTER. CURRENTLY...MODELS HAVE THE CORE OF THIS
AIR MASS ORIGINATING NEAR THE NORTH POLE TODAY. THIS AIR MASS
WILL BREAK OFF AND MOVE SOUTHWARD ACROSS CANADA AND INTO THE
NORTHERN PLAINS/UPPER MIDWEST BY SUNDAY. -20C TO -30C 85H TEMPS
ARE ASSOCIATED WITH THIS AIR MASS WHICH WILL LEAD TO DAYTIME TEMPS
IN THE SINGLE DIGITS TO AROUND ZERO ON SUNDAY. THE EC HAS BEEN THE
COLDEST WITH THIS AIR MASS AND IT REMAINS THE COLDEST WITH THE
CURRENT 12Z RUN. SATURDAY WILL SEE TEMPS NEARLY STEADY OR FALL
INTO THE TEENS AND SINGLE DIGITS BY THE EVENING. WITH WINDS
GUSTING UP TO 20 TO 25 MPH AT TIMES...WIND CHILL VALUES WILL DROP
TO NEAR -20 TO -30F BY SUNDAY MORNING OVER A WIDE AREA OF WESTERN
AND SOUTHERN MN. LITTLE RECOVERY IS EXPECTED SUNDAY WITH WIND
CHILL VALUES STILL HOLDING BETWEEN -10 TO -25F.
SOME DIFFERENCES IN THE MODELS OCCUR NEXT WEEK. HOWEVER...ALL MODELS
CONTINUE THE COLDER AIR MASS REMAINING IN PLACE THRU THE WEEK. NOT
UNTIL THIS UPPER AIR PATTERN CHANGES TO MORE WESTERLY...DOES OUR
REGION RECOVER TO NEAR NORMAL TEMPS.
ONE ITEM TO NOTE...ALTHOUGH THIS AIR MASS IS COLD...IT IS NOT AN
ANOMALY FOR THE UPPER MIDWEST FOR THE SECOND AND THIRD WEEK OF
JANUARY. THIS IS TYPICAL FOR THIS TIME...AND LOWS BELOW ZERO ARE
EXPECTED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1212 PM CST TUE JAN 5 2016
IFR CEILINGS AND VISIBILITIES IN FAR SWRN MN HAVE BEEN ERODING
THIS MORNING ON THE EAST AND NORTHEAST EDGES...WHICH IS RESULTING
IN SOME QUESTION OF THE EXTENT TO WHICH IT EXPANDS THIS EVENING
WITH NIGHTFALL. NAM SEEMS TO OVERDO IT THIS AFTERNOON...AND
LATEST RAP SEEMS MORE LIKELY...SPREADING NORTH AND NORTHEAST INTO
CENTRAL AND WEST CENTRAL MN THIS EVENING...INCLUDING KSTC...WHILE
KEEPING WISC AND ADJACENT PARTS OF MN IN VFR CONDITIONS. LATE
TONIGHT...THE RAP DRIES IT OUT OVER SW MN LATE TONIGHT...BUT AM
SKEPTICAL ABOUT THIS BEING CORRECT.
BOTTOM LINE IS IT LOOKS LIKE MVFR CEILINGS WILL BECOME WIDESPREAD
FROM SW INTO CENTRAL AND WEST CENTRAL MN THIS EVENING. HOWEVER...
IT IS QUITE UNCERTAIN WHETHER IFR CONDITIONS WILL DEVELOP LATER
TONIGHT. ALSO...TOWARD THE END OF THE PERIOD...LIGHT SNOW WILL
DEVELOP ACROSS SW MN LATE WED MORNING. SNOW SHOULD SPREAD NORTH
AND EAST WED AFTERNOON AND INTO WISC...BEYOND THE 18Z TAF END.
KMSP...
LOWS CLOUDS IN SW MN HAVE STAYED PUT FOR NOW...AND EVEN IF THEY DO
SPREAD TO THE NORTH AND NORTHEAST THIS EVENING...IT LOOKS LIKE
THEY SHOULD AVOID KMSP. AT MOST...FAR NORTHWEST METRO MIGHT SEE
THE MVFR CLOUDS THIS EVENING. MOST INDICATIONS ARE THAT MVFR CEILINGS
WILL SPREAD/DEVELOP INTO KMSP LATE TONIGHT BUT CONFIDENCE IN THIS
IS ONLY AVERAGE. LIGHT SNOW SHOULD ARRIVE MIDDAY WITH IFR CEILINGS
AND VISIBILITIES DURING MID AND LATE AFTERNOON. SOME FREEZING
DRIZZLE IS NOT OUT OF THE QUESTION WED AFTERNOON...AND WILL NOT BE
SURPRISED IF THERE ARE SOME LIFR VISIBILITIES IN SNOW LATE
WEDNESDAY AFTERNOON.
/OUTLOOK FOR KMSP/
THU...MVFR CIGS LIKELY. SLIGHT CHANCE -SN. WINDS SE 5-8 KTS.
FRI...MVFR CIGS LIKELY. -RA/-SN LIKELY. WINDS NE 5-10 KTS.
SAT...MVFR CIGS LIKELY. -SN ENDING. WINDS NW 10-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...TDK
LONG TERM...JLT
AVIATION...TDK
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1212 PM CST TUE JAN 5 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 541 AM CST TUE JAN 5 2016
ANOTHER DRY DAY IS EXPECTED WITH NEAR NORMAL TEMPS AND A MIX OF
CLOUD AND SUNSHINE.
THE CENTER OF A LARGE AREA OF HIGH PRESSURE HAS SETTLED IN ACROSS
THE OHIO VALLEY. THE HIGH EXTENDS FROM THE GULF TO THE NORTHEAST US.
MEANWHILE...MSLP IS FALLING IN THE DAKOTAS AS LONG WAVE TROUGHING
CONTINUES TO MOVE EAST FROM THE WESTERN CONUS. THE RESULT IS A
HEALTHY PRESSURE GRADIENT ACROSS THE AREA AND PRONOUNCED SOUTHWEST
FLOW. THE TEMPERATURE ADVECTION IS NEUTRAL TO SLIGHT WARM ADVECTION
BETWEEN 925MB-700MB...BUT THE MOISTURE ADVECTION IS EXPECTED TO
CONTINUE OVER THE NEXT 24 HOURS. THE AREA OF CLOUDS IN EASTERN MN
AND WESTERN WI WILL CONTINUE TO LIFT NORTHEAST WITH TIME...WHICH
WILL LIKELY LEAD TO ANOTHER CLEAR MORNING ACROSS MUCH OF EASTERN MN.
WESTERN MN IS CLEAR AT THE MOMENT...BUT CLOUD COVER IN NEBRASKA IS
EXPECTED TO LIFT NORTH WITH TIME LATE THIS MORNING.
EVENTUALLY...OVERCAST SKIES WILL SPREAD ACROSS THE AREA TONIGHT AND
THERE IS A SMALL CHANCE FOR FLURRIES OR DRIZZLE AS WE APPROACH
SUNRISE WEDNESDAY MORNING...HOWEVER...THE BEST CHANCE FOR PRECIP
WILL HOLD OFF UNTIL WEDNESDAY.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 541 AM CST TUE JAN 5 2016
LIGHT SNOW LOOKS LIKE SURE THING ON WEDNESDAY...AND THE LATE WEEK
SYSTEM APPEARS LESS AND LESS IMPRESSIVE WITH EVERY MODEL RUN.
MEANWHILE...THE COLDEST AIR OF THE SEASON WILL RUSH IN ON SATURDAY
BEHIND AN ARCTIC FRONT...WITH SUB-ZERO TEMPERATURES EXPECTED TO LAST
INTO NEXT WEEK.
WEDNESDAYS SYSTEM IS CURRENTLY COMING ONSHORE THE CALIFORNIA
COAST...AND WILL LIFT ACROSS THE REGION ON WEDNESDAY. FORECAST
SOUNDINGS SHOW DEEP SATURATION...BUT ONLY SLIGHT VEERING IN THE
WINDS...AND SPEEDS LESS THAN 30KTS THROUGHOUT THE TROPOPAUSE.
THEREFORE ONE CAN DEDUCE MINIMAL WARM AIR ADVECTION...AND MINIMAL
FORCING FOR ASCENT. THIS SUPPORTS PERSISTENT...WIDESPREAD LIGHT
SNOW...SO INCREASED POPS TO 90 PERCENT...AND CONTINUES WITH SNOWFALL
TOTALS OF 1 TO 2 INCHES. SINCE THE TOTAL WINDS ARE WEAK...ONE CAN
ASSUME THAT THE COMPONENT OF WINDS NORMAL TO THE ISOTHERMS IS ALSO
WEAK...SO THERE SHOULD NOT BE MUCH FRONTOGENETIC FORCING. THIS IS
INDEED THE CASE...SO DONT SEE THE POTENTIAL FOR HIGH END SNOWFALL
TOTALS...CERTAINLY NOT MORE THAN 3 OR 4 INCHES...WHICH MATCHES UP
WELL WITH WPC SNOWFALL PROBABILITIES.
LOOKING AHEAD...THE WEEKEND SYSTEM CONTINUES TO BRING A WINTRY MIX
OF SNOW AND RAIN ACROSS THE REGION...BUT QPF AMOUNTS ARE ONLY AROUND
A QUARTER OF AN INCH SO NOT ANTICIPATING MUCH IF ANY IMPACTS. A
COMPARISON OF THE 0-3KM MAX TEMPERATURES...TOGETHER WITH THE SURFACE
TEMPERATURES FROM THE GFS/ECMWF/NAM/GEM/SREF SHOWS THAT THE WARMEST
TEMPERATURES ARE AT THE SURFACE. WITHOUT AN ELEVATED WARM LAYER DO
NOT SEE THE RISK FOR FREEZING RAIN...BUT WITH ICE CRYSTALS COULD GET
SOME LIGHT DRIZZLE TOWARD THE TAIL END OF THE SYSTEM. ON SATURDAY
COLD AIR ADVECTION WILL BRING STRONG WINDS AND BELOW NORMAL
TEMPERATURES...WITH WIDESPREAD SUB-ZERO READINGS EXPECTED SATURDAY
NIGHT THROUGH AT LEAST EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1212 PM CST TUE JAN 5 2016
IFR CEILINGS AND VISIBILITIES IN FAR SWRN MN HAVE BEEN ERODING
THIS MORNING ON THE EAST AND NORTHEAST EDGES...WHICH IS RESULTING
IN SOME QUESTION OF THE EXTENT TO WHICH IT EXPANDS THIS EVENING
WITH NIGHTFALL. NAM SEEMS TO OVERDO IT THIS AFTERNOON...AND
LATEST RAP SEEMS MORE LIKELY...SPREADING NORTH AND NORTHEAST INTO
CENTRAL AND WEST CENTRAL MN THIS EVENING...INCLUDING KSTC...WHILE
KEEPING WISC AND ADJACENT PARTS OF MN IN VFR CONDITIONS. LATE
TONIGHT...THE RAP DRIES IT OUT OVER SW MN LATE TONIGHT...BUT AM
SKEPTICAL ABOUT THIS BEING CORRECT.
BOTTOM LINE IS IT LOOKS LIKE MVFR CEILINGS WILL BECOME WIDESPREAD
FROM SW INTO CENTRAL AND WEST CENTRAL MN THIS EVENING. HOWEVER...
IT IS QUITE UNCERTAIN WHETHER IFR CONDITIONS WILL DEVELOP LATER
TONIGHT. ALSO...TOWARD THE END OF THE PERIOD...LIGHT SNOW WILL
DEVELOP ACROSS SW MN LATE WED MORNING. SNOW SHOULD SPREAD NORTH
AND EAST WED AFTERNOON AND INTO WISC...BEYOND THE 18Z TAF END.
KMSP...
LOWS CLOUDS IN SW MN HAVE STAYED PUT FOR NOW...AND EVEN IF THEY DO
SPREAD TO THE NORTH AND NORTHEAST THIS EVENING...IT LOOKS LIKE
THEY SHOULD AVOID KMSP. AT MOST...FAR NORTHWEST METRO MIGHT SEE
THE MVFR CLOUDS THIS EVENING. MOST INDICATIONS ARE THAT MVFR CEILINGS
WILL SPREAD/DEVELOP INTO KMSP LATE TONIGHT BUT CONFIDENCE IN THIS
IS ONLY AVERAGE. LIGHT SNOW SHOULD ARRIVE MIDDAY WITH IFR CEILINGS
AND VISIBILITIES DURING MID AND LATE AFTERNOON. SOME FREEZING
DRIZZLE IS NOT OUT OF THE QUESTION WED AFTERNOON...AND WILL NOT BE
SURPRISED IF THERE ARE SOME LIFR VISIBILITIES IN SNOW LATE
WEDNESDAY AFTERNOON.
/OUTLOOK FOR KMSP/
THU...MVFR CIGS LIKELY. SLIGHT CHANCE -SN. WINDS SE 5-8 KTS.
FRI...MVFR CIGS LIKELY. -RA/-SN LIKELY. WINDS NE 5-10 KTS.
SAT...MVFR CIGS LIKELY. -SN ENDING. WINDS NW 10-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
$$
SHORT TERM...CLF
LONG TERM...JRB
AVIATION...TDK
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
339 PM CST TUE JAN 5 2016
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 336 PM CST TUE JAN 5 2016
THE HRRR MODEL WHICH I HAVE NOT BEEN ABLE TO SEE SINCE THE 12Z
RUN...AT LEAST HAD AN EXCELLENT HANDLE ON THE LOW CLOUDS OVER THE
AREA AT THAT TIME. THE STRATUS CONTINUES TO CLEAR STEADILY FROM THE
SOUTH/SOUTHEAST AND IS ACCOMPANIED BY A SLOWER EROSION ON THE
WESTERN SIDE. THIS WILL LEAVE ONLY A LITTLE WEDGE FROM ROUGHLY DE
SMET TO BROOKINGS LATE AFTERNOON AND THAT SHOULD CONTINUE TO CLEAR
AS THE DECENT LOW LEVEL FLOW CONTINUES.
OTHERWISE...TONIGHT WILL BRING HIGH AND THEN MIDDLE CLOUDS
INCREASING FROM THE SOUTH AS A WEAK UPPER WAVE APPROACHES FROM THE
SOUTHWEST. LOW CLOUDS SHOULD BE INCREASING AGAIN BY EARLY WEDNESDAY
MORNING BUT OF COURSE THE MORE IMPORTANT ISSUE WILL BE THE ARRIVAL
OF LIGHT PRECIPITATION WITH THIS WAVE. IT STILL LOOKS LIKE JUST A
SLIGHT CHANCE FAR SOUTH LATE TONIGHT...THOUGH OF COURSE THE
PRECIPITATION IS LIKELY TO BE INCREASING IN COVERAGE IN THE LAST
COUPLE OF HOURS BEFORE SUNRISE...WHICH FOR WEDNESDAY IS STILL AT OUR
LATEST 8 AM SHARP TIME FOR SIOUX FALLS. AREAS OF LIGHT
PRECIPITATION WILL SPREAD MOSTLY OVER NORTHWEST IOWA INTO THE
EASTERN PART OF SOUTHWEST MINNESOTA THROUGH EARLY AFTERNOON. WILL GO
WITH LIKELY POPS FAR EAST AND CHANCE/SLIGHT CHANCE BACK WEST INTO
SOUTHEAST SOUTH DAKOTA...WITH GREATER COVERAGE LIKELY JUST EAST OF
THE AREA. AMOUNTS THROUGH WEDNESDAY SHOULD BE BELOW A TENTH OF AN
INCH.
A FAIRLY LOW AND SHALLOW WARM LAYER WILL MEAN THE START OF
PRECIPITATION MAY BE A MIXTURE OF SLEET SNOW AND FREEZING RAIN/RAIN.
THIS WARM LAYER SHOULD COOL AS THE DAY PASSES AND WITH THE DURATION
OF ANY PRECIPITATION SO EXPECT PRETTY MUCH ALL SNOW FOR THE
AFTERNOON. IN LINE WITH THE LIGHT PRECIPITATION NATURE...ANY SNOW
ACCUMULATIONS THROUGH WEDNESDAY SHOULD BE LESS THAN AN INCH.
THROUGH ALL THIS...TEMPERATURES WILL NOT SHOW MUCH DROP TONIGHT WITH
PERIODS OF STEADY TEMPERATURES OR EVEN SLIGHT WARMING POSSIBLE.
WEDNESDAY LIKEWISE WILL NOT SHOW MUCH WARMING WITH HIGHS AT MOST A
DEGREE OR TWO ABOVE FREEZING. WINDS WILL KEEP THEIR SOUTHERLY
NATURE BUT DECREASE SLOWLY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 336 PM CST TUE JAN 5 2016
ACTIVE WEATHER IN THE MID RANGE WILL BE FOLLOWED BY MUCH COLDER AND
DRY WEATHER BEGINNING THIS WEEKEND.
SHORTWAVE LIFTING NORTHEAST THROUGH THE REGION ON WEDNESDAY WILL
EXIT THE AREA WEDNESDAY NIGHT. WHILE MEASURABLE PRECIPITATION
CHANCES FALL OFF QUICKLY IN THE EVENING AS THE WAVE PULLS AWAY...LOW
STRATUS WILL LINGER OVERNIGHT. WITH THETA E ADVECTION AND PLENTY OF
LOW LEVEL MOISTURE...EXPECT THAT SOME DRIZZLE OR FREEZING DRIZZLE
WILL SPREAD ACROSS THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY.
TEMPERATURES REMAIN MILD...WITH HIGHS WITHIN A FEW DEGREES ABOVE AND
BELOW FREEZING.
THE NEXT SHORTWAVE LIFTS NORTH NORTHEAST FROM THE CENTRAL PLAINS
THURSDAY EVENING...REACHING THE WESTERN GREAT LAKES ON FRIDAY
AFTERNOON. LIGHT PRECIPITATION WILL SPREAD INTO NORTHWEST IOWA
THURSDAY AFTERNOON AND SPREAD ACROSS THE REST OF THE FORECAST AREA
THURSDAY NIGHT AND FRIDAY MORNING. PRECIPITATION CHANCES LOOK TO BE
HIGHEST IN OUR FAR EAST WITH THIS SYSTEM...TAPERING TO LOW END
CHANCES IN OUR WEST. WHILE PRECIPITATION AMOUNTS ARE NOT
PARTICULARLY HIGH...DID BOOST POPS TO CATEGORICAL IN OUR FAR
SOUTHEAST. PRECIPITATION TYPE WILL PRIMARILY BE SNOWFALL...BUT WITH
HIGH TEMPERATURES NEAR OR JUST ABOVE FREEZING IN OUR EAST WHERE THE
HIGHEST AMOUNTS ARE EXPECTED. RAIN MAY MIX WITH SNOW AT TIMES...AND
WILL HELP KEEP SNOWFALL AMOUNTS FAIRLY LOW. PRELIMINARY
AMOUNTS...EXPECT AROUND 1 TO 3 INCHES OF SNOW IN THE EAST...WITH
LESS THAN AN INCH WEST OF I29.
BEHIND THIS SYSTEM...MUCH COLDER AIR FILTERS INTO THE REGION FROM
CANADA. DEEP TROUGH LINGERS OVER THE NORTHERN PLAINS THIS WEEKEND
INTO EARLY NEXT WEEK. BREEZY NORTHERLY WINDS ON FRIDAY AND SATURDAY
WILL ALLOW TEMPERATURES TO FALL FRIDAY AFTERNOON AND
OVERNIGHT...REMAINING STEADY OR SLOWLY FALLING DURING THE DAY
SATURDAY. LOWS SATURDAY NIGHT AND SUNDAY NIGHT WILL DROP BELOW ZERO
AREAWIDE...WITHOUT MUCH IMPROVEMENT DURING THE DAY ON SUNDAY. RIGHT
NOW IT LOOKS LIKE AT LEAST OUR NORTHERN HALF WILL SEE ADVISORY LEVEL
WIND CHILLS SUNDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1130 AM CST TUE JAN 5 2016
CEILINGS NEAR 1K FEET OVER THE CENTRAL AND NORTHEAST PARTS OF THE
AREA WILL DECREASE FROM THE SOUTH AND WEST THROUGH 06/00Z...LEAVING
THE AREA WITH VFR AT THAT TIME. VFR CONDITIONS ARE EXPECTED 06
/00Z-09Z. 06/09Z-18Z CEILINGS 1-2K FEET WILL INCREASE FROM THE
SOUTH AND WEST OVER THE AREA. AREAS OF VISIBILITIES 3-5SM/-IPSN
WILL DEVELOP OVER NORTHWEST IA AND EXTREME SOUTHEAST SD AFTER
06/12Z...SPREADING INTO SOUTHWEST MN BY 06/18Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...
AVIATION...
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1128 AM CST TUE JAN 5 2016
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 426 AM CST TUE JAN 5 2016
MORE ACTIVE STRETCH BEGINS WEDNESDAY AFTERNOON...CONTINUING INTO
THE WEEKEND. SPENT MOST WORK TRYING TO PIN DOWN PRECIPITATION
TYPES...TIMING...AND CHANCES FOR THE LIGHTER PRECIPITATION
WED/THU...AND WEATHER SYSTEM ON THURSDAY NIGHT AND FRIDAY.
GOES WATER VAPOR IMAGERY SHOWING A NICE SHORTWAVE TROUGH MOVING
TOWARD KMSP WITH MAIN INFLUENCE IN THE 500MB AND ABOVE LAYER PER
RAP TROPOPAUSE FOLD DEPTH TO 400 MB. AIR MASS ALOFT IS QUITE DRY
AND DO NOT EXPECT WEATHER FROM IT. MORE IMPRESSIVE SHORTWAVE
TROUGH OVER SWRN NEW MEXICO AT 09Z CLEARLY VISIBLE AND LIFTING
NORTHEAST...THIS WILL BRING PRECIPITATION IN FOR
WEDNESDAY AFTERNOON-NIGHT...AND NEXT TROUGH APPROACHING SRN CA IS
LATE THU-FRI WEATHER.
LOW CLOUDS IN FOG PRODUCT HAVE BEEN PRETTY BEHAVED TONIGHT SLIDING
NORTH IN THE STRONGER LOW-LEVEL SOUTHERLY FLOW. HOWEVER...THE
SOUTHERN PORTION IS ANCHORED NEAR KDSM AND I-80...SO THIS ISNT ALL
THAT EASY. BOTTOM LINE IS KEPT WI MOSTLY SUNNY WITH MN/IA SLOWLY
SEEING MORE SUNSHINE AS DAY PROGRESSES. GSD HRRR MODEL RUN SEEMS
TO HAVE THE BEST IDEA ON NORTHWARD TRACK.
WEDNESDAY AFTERNOON AND OVERNIGHT...
CONSISTENT SIGNAL CONTINUES FOR THIS PERIOD WITH VERY WEAK
FRONTOGENESIS TO THE NORTHWEST OVER MN...SHORTWAVE TROUGH FROM
NEW MEXICO APPROACHING THE AREA WITH WEAK QVECTOR
CONVERGENCE...WEAK ISENTROPIC UPGLIDE /280-290K/...AND SOME
INCREASE IN MOISTURE /2-4 G/KG/ ON A PLUME FROM WRN IA INTO MN
WEDNESDAY AFTERNOON. THIS ALL EVOLVES EASTWARD WEDNESDAY NIGHT
HOWEVER...IT STILL APPEARS THE BEST LIFT IS NORTHWESTERN AREAS OF
THE FORECAST AREA. KEPT FORECAST ABOUT THE SAME BUT ADDED MORE
TIMING TO PRECIPITATION CHANCES. STILL LOOKING LIKE A 1 INCH
SNOW. THERE IS SOME SUGGESTION OF A BIT OF A WARM LAYER BEFORE
FULL SATURATION OCCURS WHICH COULD MIX IN A BIT OF SLEET FOR AN
HOUR OR SO.
THE SHORTWAVE TROUGH WILL SHIFT EAST THURSDAY AND TAKE WITH IT
THE DEEP SATURATION...AND THE FORECAST AREA WILL LOSE ICE CLOUD
FROM SW TO NE. THIS SIGNAL HAS BEEN IN THE MODEL GUIDANCE...ACROSS
THE MODELS...FOR DAYS NOW...AND HAVE DECIDED TO ADD THE
POSSIBILITY OF DZ/FZDZ TO THE FORECAST. THE SATURATED LIQUID LAYER
IS OVER 2KM DEEP WITH SOME RESIDUAL LIFT AS THE TROUGH MOVES
EAST...WITH ABOUT 2-3 UB/S OF LIFT IN THE LAYER. HAVE LOWERED THE
PRECIPITATION CHANCES THURSDAY...SO IT LOOKS LIKE A CHANCE OF
FZDZ IN THE MORNING...THEN DZ IN THE AFTERNOON AS TEMPERATURES
WARM. ONLY A SKIM OF ICING WOULD BE POSSIBLE IF ANYTHING
MATERIALIZES AT ALL.
.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 426 AM CST TUE JAN 5 2016
THURSDAY NIGHT THROUGH FRIDAY...
THE 05.06Z MODEL GUIDANCE HAS REALLY COME INTO BETTER AGREEMENT
ON THE STRONGER SHORTWAVE TROUGH OF THE WEEK AND THE ONSET OF
PRECIPITATION INTO THE SOUTH THURSDAY EVENING WITH WARM ADVECTION
BURST....AND THE DEFORMATION BAND ROTATING NORTHWEST FRIDAY IN
CONCERT WITH A LOW-LEVEL INVERTED TROUGH. IT APPEARS THERE ARE
TWO INDIVIDUAL WAVES THAT WILL AFFECT THE AREA SO THIS PERIOD IS A
BIT MORE COMPLEX. THE LOW-LEVEL CYCLONE /925-850MB/ APPEARS TO BE
MORE CONSOLIDATED...WHICH COULD LEAD TO A FAIRLY NICE DEFORMATION
REGION WITH THIS SYSTEM FRIDAY. WITH THE TRACK THROUGH NRN IL...IT
APPEARS ONLY CENTRAL/SWRN WI AND FAR NERN IA WILL HAVE
PRECIPITATION TYPE ISSUES...AND SNOW TO THE NORTHWEST. EARLY SNOW
AMOUNTS SNOW LOOK LIKE 1-3 INCHES...WITH SOME RAIN OR SLEET
FURTHER SOUTHEAST. WILL NEED TO KEEP OUR EYE ON THIS ONE AS IT HAS
SOME GOOD ATTRIBUTES FOR A BIT HIGHER IMPACT IF IT STRENGTHENS
MORE.
SATURDAY THROUGH MONDAY...
DEEP TROUGH MOVE IN FROM THE NORTHWEST WITH PROBABLY A LIGHT SNOW
BURST ON THE FRONT...AND STRONG COLD ADVECTION. SATURDAY WILL BE
THE LAST NEAR NORMAL DAY WITH GOOD AGREEMENT ON THE COLD WEEK
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY NOON)
ISSUED AT 1128 AM CST TUE JAN 5 2016
GOOD VFR CONDITIONS EXPECTED THIS PERIOD AS HIGH PRESSURE DRIFTS
EAST OF THE UPPER MIDWEST. MAIN CLOUDS THRU MID MORNING WED WILL BE
SCT-BKN NEAR/ABOVE 15K FT. BY LATER WED MORNING...SOME LOWER
MOISTURE AND MVFR CLOUDS...AHEAD OF THE NEXT SYSTEM COMING ACROSS
THE PLAINS...WILL START TO SPREAD EAST ACROSS THE AREA. BROUGHT A
SCT025 LAYER INTO KRST AFTER 14Z TO REFLECT THIS.
OTHERWISE...THE MAIN CONCERN FOR THIS AFTERNOON THRU 18Z WED WILL BE
STRONGER SOUTH WINDS AS THE TIGHTER PRESSURE GRADIENT ON THE BACK
SIDE OF THE RETREATING HIGH MOVES ACROSS THE AREA. SOUTH WINDS 15-
20KT G25-30KTS EXPECTED THIS AFTERNOON AND MUCH OF TONIGHT...
ESPECIALLY ACROSS THE HIGHER TERRAIN AREAS AND RIDGE-TOPS /KRST/.
WINDS IN THE MS/WI RIVER VALLEYS /KLSE/ NOT LOOKING TO MIX AS
MUCH...REMAINING MORE SOUTH 10-15KTS THRU THE PERIOD. WITH SOUTHWEST
WINDS AROUND 40KTS IN THE 1500-2000 FT AGL MUCH OF TONIGHT...DID ADD
LLWS TO KLSE TAF IN THE 00-09Z PERIOD. 925MB GRADIENT LOOKS TO RELAX
AFTER 09Z...WITH SOUTHWEST WINDS AROUND 2K FT MORE IN THE 30KT RANGE
BY 12-15Z WED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM....BAUMGARDT
AVIATION.....RRS