Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/17/16
AREA FORECAST DISCUSSION
NWS TUCSON AZ
1005 AM MST FRI JAN 15 2016
.SYNOPSIS...A FEW SHOWERS NORTHEAST OF TUCSON INTO THIS EVENING
WITH BREEZY WINDS AT TIMES. OTHERWISE...DRY CONDITIONS WILL PREVAIL
ACROSS MUCH OF THE AREA THIS WEEKEND AND DURING THE UPCOMING WEEK.
A WEATHER SYSTEM MAY BRING A FEW SHOWERS MAINLY TO THE WHITE
MOUNTAINS WEDNESDAY. EXPECT COOL MORNINGS THIS WEEKEND EVEN AS
DAYTIME TEMPERATURES CLIMB ABOVE AVERAGE BY MONDAY.
&&
.DISCUSSION...A POSITIVE TILTED SHORTWAVE TROUGH WAS OVER THE GREAT
BASIN THIS MORNING. IR SATELLITE IMAGERY DURING THE PAST 2-3 HOURS
DEPICTED COOLING CLOUD TOPS AHEAD OF THIS SYSTEM...ESPECIALLY OVER
NORTH CENTRAL/NE ARIZONA. THIS SYSTEM IS PROGGED VIA THE 15/12Z NAM/
GFS/CMC AND 15/00Z ECMWF TO MOVE SEWD ACROSS THE FOUR CORNERS REGION
THIS EVENING. THE MID-LEVEL TROUGH AXIS IS THEN PROGGED TO BE EAST
OF THIS FORECAST AREA BY MIDNIGHT TONIGHT.
BASED ON THE ABOVE NWP SOLUTIONS AS WELL AS SEVERAL HRRR SOLUTIONS...
THE OFFICIAL FORECAST WAS UPDATED WITH SOMEWHAT HIGHER POPS
PARTICULARLY ACROSS THE WHITE MOUNTAINS THIS AFTERNOON AND EVENING.
HOWEVER...LIQUID AMOUNTS AND SNOW ACCUMULATIONS WERE ESSENTIALLY
UNCHANGED. THUS...SCATTERED TO NUMEROUS SNOW SHOWERS ARE FORECAST
TO OCCUR THIS AFTERNOON/EVENING ACROSS THE MOUNTAINS OF GRAHAM/
GREENLEE COUNTIES.
MEANWHILE...ISOLATED VALLEY RAIN SHOWERS SHOULD ALSO OCCUR ACROSS
GRAHAM COUNTY INCLUDING SAFFORD...AND A SLIGHT CHANCE OF SNOW SHOWERS
CONTINUES FURTHER SOUTHWEST TO THE CATALINA/RINCON MOUNTAINS NEAR
TUCSON. ANY MEASURABLE PRECIP IS EXPECTED TO END AROUND MIDNIGHT
TONIGHT. LIQUID AMOUNTS WILL BE MAINLY LESS THAN ONE TENTH OF AN
INCH. SNOW ACCUMS FOR HANNAGAN MEADOW AND MOUNT GRAHAM WILL RANGE
FROM 1-2 INCHES...AND LITTLE IF ANY SNOW ACCUMS WILL OCCUR ACROSS THE
CATALINA/RINCON MOUNTAINS.
GUSTY WEST-TO-NORTHWEST WINDS WILL ALSO PREVAIL THIS AFTERNOON AND
EVENING...WITH STRONGEST WINDS TO OCCUR ACROSS THE UPPER GILA RIVER
VALLEY INCLUDING SAFFORD. HIGH TEMPS TODAY WILL BE NEARLY IDENTICAL
TO TEMPS ACHIEVED THUR FROM TUCSON WWD ACROSS THE WESTERN DESERTS...
BUT WILL BE ABOUT 5 DEGS COOLER EAST AND SOUTH OF TUCSON.
PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL.
&&
.AVIATION...VALID THRU 16/18Z.
EXPECT ISOLATED TO SCATTERED -SHRA AND HIGHER TERRAIN -SHSN
GENERALLY FROM KSAD VICINITY NEWD ACROSS THE WHITE MOUNTAINS THIS
AFTERNOON AND EVENING. THIS PRECIPITATION SHOULD BE EAST OF THE
SOUTHEAST ARIZONA/SOUTHWEST NEW MEXICO BORDER BY 17/07Z. OTHERWISE...
SCATTERED TO BROKEN CLOUDS AROUND 10K-15K FT MSL WITH LAYERED CLOUDS
ABOVE 20K FT MSL INTO SATURDAY MORNING. SURFACE WIND THIS AFTERNOON
AND EARLY EVENING WILL BE WLY/NWLY AT 12-25 KTS WITH GUSTS OF 25-35
KTS. THE STRONGEST WINDS WILL BE EAST OF KTUS. SURFACE WIND WILL
DIMINISH TO LESS THAN 10 KTS ACROSS MUCH OF THE AREA AROUND 17/07Z
AND CONTINUE INTO SATURDAY MORNING. AVIATION DISCUSSION NOT
UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...ISOLATED TO SCATTERED VALLEY RAIN AND MOUNTAIN SNOW
SHOWERS WILL OCCUR FROM THE CATALINA/RINCON MOUNTAINS NEAR TUCSON
NORTHEASTWARD TO THE WHITE MOUNTAINS THIS AFTERNOON AND EVENING. A
SLIGHT CHANCE OF VALLEY RAIN/MOUNTAIN SNOW SHOWERS EXISTS TUESDAY
NIGHT AND WEDNESDAY FROM TUCSON EASTWARD TO THE NEW MEXICO BORDER.
OTHERWISE...DRY CONDITIONS WILL PREVAIL THROUGH NEXT THURSDAY.
FRIDAY. EXPECT WEST TO NORTHWEST 20-FOOT WINDS OF 10-20 MPH WITH
GUSTS TO AROUND 30 MPH THIS AFTERNOON AND EVENING. THE STRONGEST
WINDS WILL BE EAST OF TUCSON AND ESPECIALLY ACROSS THE UPPER GILA
RIVER VALLEY INCLUDING SAFFORD. OTHERWISE...20-FOOT WINDS WILL
GENERALLY BE TERRAIN DRIVEN AT LESS THAN 15 MPH.
&&
.PREV DISCUSSION /245 AM MST/...AFTER FEW CHILLY MORNINGS SATURDAY
INTO MONDAY A RIDGE BRINGS A RETURN OF THE AFTERNOON WARMING TREND TO
THE FORECAST EARLY NEXT WEEK. SOME MODEL DIFFERENCES ON A POSSIBLE
SYSTEM NEXT WEDNESDAY...BUT EVEN WITH THE MOST AGGRESSIVE MODEL
RESOLUTIONS THE PATTERN DOES NOT SUPPORT A SYSTEM THAT WOULD DELIVER
SIGNIFICANT PRECIP TO THE AREA. SOME EARLY SIGNS OF ANOTHER PATTERN
CHANGE LATE IN THE MONTH THAT WOULD TEND TO SPLIT ENERGY INTO LOWER
LATITUDES OFF THE PACIFIC AGAIN.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
FRANCIS/MEYER/HUMPHREYS
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
403 PM PST SAT JAN 16 2016
.SYNOPSIS...ISOLATED TO SCATTERED SHOWERS WILL PERSIST OVER THE
REGION THROUGH THIS EVENING BEFORE A BRIEF BREAK IN PRECIPITATION
TONIGHT. THE NEXT STORM SYSTEM WILL BE STRONGER AND RESULT IN
WIDESPREAD RAINFALL, HEAVY AT TIMES, ALONG WITH GUSTY WINDS FROM
SUNDAY AFTERNOON THROUGH MONDAY MORNING. A WET WEATHER PATTERN WILL
PERSIST THROUGH MUCH OF NEXT WEEK AS A SERIES OF STORM SYSTEMS
IMPACT THE REGION.
&&
.DISCUSSION...AS OF 01:45 PM PST SATURDAY...SHOWERS HAVE
INCREASED IN COVERAGE OVER THE REGION DURING THE PAST FEW HOURS AS
A WEAK SHORT-WAVE APPROACHES. THIS ACTIVITY WILL LIKELY PERSIST
THROUGH THE AFTERNOON AND INTO THE EARLY EVENING BEFORE
DIMINISHING IN COVERAGE DURING THE OVERNIGHT HOURS. MOST LOCATIONS
WILL GENERALLY RECEIVE AN ADDITIONAL FEW HUNDREDTHS TO AS MUCH AS
A TENTH OF AN INCH THROUGH THIS EVENING. A BRIEF LULL IN ACTIVITY
IS THEN EXPECTED DURING THE OVERNIGHT HOURS, WITH THE EXCEPTION
BEING ACROSS THE NORTH BAY WHERE SHOWERS MAY LINGER THROUGH THE
NIGHT.
OUR NEXT, STRONGER STORM SYSTEM REMAINS ON TRACK TO IMPACT THE
REGION FROM LATE SUNDAY MORNING OR EARLY AFTERNOON THROUGH MONDAY
MORNING. PWAT VALUES ARE FORECAST TO APPROACH OR EXCEED 1.25" WITH
THIS SYSTEM AND WILL LIKELY RESULT IN MODERATE TO OCCASIONALLY
HEAVY RAINFALL RATES AS THE MAIN BAND OF PRECIPITATION SWEEPS
ACROSS THE REGION. THE GREATEST RAINFALL AMOUNTS WILL BE ACROSS
THE NORTH BAY WHERE THE BOUNDARY WILL BE SLOW TO MOVE THROUGH
EARLY SUNDAY BEFORE SPEEDING UP DURING THE AFTERNOON/EVENING HOURS.
WITH WIDESPREAD 1.5" TO AS MUCH AS 2.5" OF RAINFALL EXPECTED
ACROSS THIS REGION, A FLASH FLOOD WATCH HAS BEEN ISSUED FROM EARLY
SUNDAY MORNING THROUGH MONDAY MORNING. THE MAIN THREAT WILL BE FOR
LOCALIZED URBAN AND SMALL STREAM FLOODING, ESPECIALLY OF LOW-LYING
OR POORLY DRAINED AREAS ACROSS THE NORTH BAY. THE HEAVIEST
PRECIPITATION WILL THEN SPREAD SOUTHWARD ACROSS THE SAN FRANCISCO
BAY AREA SUNDAY AFTERNOON AND EVENING BEFORE PUSHING INTO THE
MONTEREY BAY REGION LATER IN THE DAY AND INTO EARLY MONDAY
MORNING. URBAN AREAS SOUTH OF THE GOLDEN GATE CAN EXPECT BETWEEN
0.75" TO 1.50" OF RAINFALL THROUGH MONDAY MORNING. COASTAL RANGES
IN THE NORTH BAY WILL LIKELY SEE RAINFALL AMOUNTS BETWEEN 2.25"
TO 3.5O" WHILE RANGES DOWN THE COAST CAN EXPECT 1.50" TO 2.25"
FROM THIS SYSTEM. MEANWHILE, SOME OF THE MOST INLAND, SOUTHERN
VALLEY LOCATIONS MAY RECEIVE LESS THAN 0.50". IN ADDITION TO THE
WIDESPREAD RAINFALL, SOUTHERLY WINDS WILL INCREASE AHEAD OF THIS
SYSTEM AND BE GUSTY AT TIMES AS THE FRONTAL BOUNDARY SWEEPS
THROUGH. WIND SPEEDS OF 20 TO 30 MPH WITH LOCALLY HIGHER GUSTS CAN
BE EXPECTED AT TIMES ON SUNDAY.
AFTER A BRIEF LULL IN PRECIPITATION MONDAY AFTERNOON AND EVENING,
ANOTHER ROUND OF RAIN IS FORECAST TO SWEEP THROUGH THE REGION LATE
MONDAY NIGHT INTO TUESDAY MORNING. THIS SYSTEM WILL ALSO HAVE A DEEP
MOISTURE TAP, RESULTING IN THE POTENTIAL FOR LOCALLY HEAVY RAINFALL
AND GUSTY SOUTHERLY WINDS. AN ADDITIONAL 0.25" TO 0.50" CAN BE
EXPECTED IN MOST URBAN AREAS WITH AS MUCH AS 1.00" IN THE NORTH BAY
VALLEYS. AS THIS SYSTEM IS CURRENTLY FORECAST TO MOVE THROUGH A BIT
FASTER THAN THE SUNDAY/MONDAY SYSTEM, COASTAL RANGES CAN EXPECT
RAINFALL AMOUNTS OF 0.75" TO 1.50" FROM LATE MONDAY NIGHT INTO
TUESDAY MORNING. TEMPERATURES THROUGH EARLY NEXT WEEK ARE NOT
FORECAST TO FLUCTUATE MUCH, WITH DAYTIME VALUES GENERALLY WARMING
INTO THE MID/UPPER 50S TO LOWER 60S AND OVERNIGHT LOWS IN THE
MID/UPPER 40S TO LOWER 50S.
AN UNSETTLED PATTERN APPEARS TO PERSIST INTO THE LATTER HALF OF
THE UPCOMING WORKWEEK WITH ADDITIONAL SYSTEMS CURRENTLY FORECAST
TO IMPACT THE REGION. THE NEXT STRONGEST APPEARS TO BE LATE
THURSDAY INTO FRIDAY WITH ANOTHER AROUND OF WIDESPREAD
PRECIPITATION POSSIBLE. HOWEVER, DETAILS IN EXACT AMOUNTS AND
LOCATIONS OF HEAVIEST PRECIPITATION REMAIN DIFFICULT TO PINPOINT
AT THIS TIME. BE SURE TO CONTINUE TO MONITOR THE LATEST FORECASTS
IN THE COMING DAYS AS THE WET WEATHER PATTERN PERSISTS OVER MUCH
OF THE REGION.
&&
.AVIATION...AS OF 4:02 PM PST SATURDAY...RELATIVELY WARM MOIST
AIR FILTERING IN AHEAD OF THE NEXT STORM SYSTEM IS RESULTING IN
SOME INTERESTING WEATHER AROUND THE FORECAST AREA THIS AFTERNOON.
THIS WARM MOIST AIR WITH SOME GENTLE ASCENT IS RESULTING IN MVFR
CIGS AT MOST OF THE TERMINALS WITH LIGHT RAIN AND REDUCED
VISIBILITY AT MONTEREY. THESE CONDITIONS WILL MOST LIKELY STICK
AROUND THROUGH THE EVENING HOURS. WITH WET RUNWAYS LIKELY SUNDAY.
VICINITY OF KSFO...MVFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH
A MAJORITY OF THE FORECAST PERIOD WITH LIGHT RAIN AND OCCASIONAL
REDUCED VIS POSSIBLE.
CONFIDENCE IS LOW.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...LIFR CIGS AND POOR VIS ARE
ANTICIPATED TO PREVAIL AT KMRY THIS EVENING WITH MVFR AT KSNS.
LIGHT RAIN WILL PERSIST THROUGH THIS EVENING.
CONFIDENCE IS LOW.
&&
.MARINE...AS OF 09:30 AM PST SATURDAY...SOUTHERLY WINDS WILL
INCREASE ONCE AGAIN TONIGHT AS THE NEXT IN A SERIES OF FRONTAL
SYSTEMS APPROACHES THE REGION. THE STRONGEST WINDS WILL BE OVER
THE NORTHERN OUTER WATERS. A LARGE LONG PERIOD SWELL WILL MOVE
INTO THE FORECAST AREA THIS AFTERNOON AND PERSIST THROUGH THE
HOLIDAY WEEKEND BEFORE EASING EARLY NEXT WEEK.
&&
.BEACHES...AS OF 10:00 AM PST SATURDAY... AN APPROACHING WEST
SWELL WILL BRING HAZARDOUS CONDITIONS TO REGIONAL BEACHES FROM
SATURDAY AFTERNOON INTO MONDAY. VERY LONG PERIOD FORERUNNER WAVES
HAVE BEGUN TO MIX INTO THE CURRENT WAVE SETS AT THE COASTLINE
THIS MORNING... AND WILL CONTINUE TO BUILD THROUGH THE DAY. WEST
SWELLS WILL STEADILY INCREASE TO 16 TO 20 FEET WITH A PERIOD OF 18
TO 21 SECONDS THROUGH SATURDAY AFTERNOON AND OVERNIGHT TONIGHT.
WAVES WILL BE LARGEST ON SUNDAY...ESPECIALLY SUNDAY MORNING.
EXTREME WAVE RUN UP IS EXPECTED WITH THIS SWELL AS LONG LULLS IN
BETWEEN WAVE SETS WILL INCREASE RISK OF DEADLY RIP
CURRENTS...LARGE SNEAKER WAVES... AND THE LIKELIHOOD OF BEING
WASHED INTO SEA BY A WAVE. SMALL VESSELS ALONG THE IMMEDIATE COAST
MAY ALSO BE PUSHED INTO COASTAL ROCKS. DURING HIGH TIDE... COASTAL
INUNDATION MAY CUT OFF ACCESS TO SOME BEACHES AND OUTCROPPINGS.
THE LARGE WAVES WILL GRADUALLY TAPER OFF EARLY NEXT WEEK.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...HIGH SURF WARNING...ENTIRE COAST
FLASH FLOOD WATCH...ENTIRE NORTH BAY REGION
SCA...PT ARENA TO PT REYES 0-10 NM FROM 9 PM
SCA...PT ARENA TO PIGEON PT 10-60 NM FROM 9 PM
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: RGASS
AVIATION: LARRY
MARINE: DRP
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[top]
Area Forecast Discussion
National Weather Service Sacramento CA
201 PM PST SAT JAN 16 2016
.SYNOPSIS...
CURRENT SYSTEM WILL CONTINUE TO BRING SHOWERS TODAY WITH SOME
MOUNTAIN SNOW ACCUMULATION. WETTER SYSTEM EXPECTED SUNDAY THROUGH
EARLY MONDAY. SOME SMALL SCALE AND/OR BURN SCAR FLOODING COULD
OCCUR DURING THIS TIME. EXPECT PERIODS OF PRECIPITATION THROUGH
NEXT WEEK.
.SHORT TERM DISCUSSION (TODAY THROUGH TUESDAY)...
A series of storms will move through the region through Tuesday.
The current system is exiting the region with shower chances
continuing into the evening. Snow levels have been risen up to
around 7500 feet and will remain high through Tuesday but may dip
at times below major pass levels of US-50 and I-80. I have
modified the flash flood watch period to when the heavier rain is
expected to move through Lake County for Sunday afternoon and
evening. Timing of the later system on Tuesday may change a
little.
In the shorter term the NAM and HRRR models are indicating showers
enhancing around mid afternoon over the Southern Sacramento
Valley and Western Slopes of the Sierra Nevada. Showers should
taper some this evening then rain may start for places around I-80
and to the north later tonight and Sunday morning. The heaviest
rainfall is expected Sunday afternoon and evening. Sunday evening
snow levels look like they may lower below major Sierra pass
levels and have some impact on travel.
.EXTENDED DISCUSSION (Wednesday THROUGH Saturday)
Unsettled weather pattern will continue through next week as
several storms move into NorCal from the Pacific. Forecast timing
will likely fluctuate over the next several runs under this
progressive pattern, but confidence is high in both a midweek and
late-week storm over the region. Snow levels will generally remain
around 5000-7000 feet before lowering next weekend. Temperatures
will be close to average for mid-January.
Dang
&&
.AVIATION...
Wly flow alf as upr rdg movs thru tngt...bckg to SWly Sun as nxt
Pac fntl sys movs into Intr NorCal. For Cstl/Shasta mtns and Cntrl
Vly...lcl MVFR/IFR bcmg wdsprd MVFR with areas IFR aft 12z Sun. Ovr
Wrn Plumas/Siernev lcl MVFR bcmg wdsprd MVFR/IFR with lcl LIFR aft
17z Sun. Sn lvls genly aoa 055 msl. Lcl SEly sfc wnd gsts to 25 kts
Sun with SWly sfc wnd gsts to 40 kts poss ovr hyr mtn trrn.
&&
.STO Watches/Warnings/Advisories...
Flash Flood Watch from Sunday afternoon through Sunday evening
for Clear Lake/Southern Lake County-Mountains Southwestern
Shasta County to Northern Lake County.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
104 PM PST FRI JAN 15 2016
...SERIES OF SYSTEMS TO IMPACT OUR AREA THROUGH THE END OF NEXT
WEEK WITH THE STRONGEST SYSTEM EXPECTED SUNDAY EVENING INTO MONDAY
MORNING...
.SYNOPSIS...A WEAK SYSTEM IS EXPECTED TO MOVE ACROSS NORTHERN
CALIFORNIA LATER TODAY AND BRING RAIN BACK TO OUR AREA TONIGHT. A
SERIES OF SYSTEMS WILL AFFECT THE AREA SATURDAY THROUGH AT LEAST
THE END OF NEXT WEEK. THE STRONGEST SYSTEM IS SLATED FOR SUNDAY
EVENING INTO TUESDAY.
&&
.DISCUSSION...AS OF 1:00 PM PST FRIDAY...MIX OF CLOUDS AND SUN
ACROSS THE REGION TODAY WITH TEMPERATURES RUNNING CLOSE TO VALUES
24 HOURS AGO. TEMPS DO RANGE FROM THE LOWER 50S IN THE NORTH BAY
WHERE CLOUDS HAVE BEEN VERY SLOW TO BURN OFF, TO THE UPPER 50S TO
LOWER 60S FOR THE REST OF OUR AREA THAT ENJOYED MORE SUNSHINE.
A WEAK SYSTEM WILL MOVE TO THE COAST THIS EVENING WITH RAINFALL
FORECAST TO RETURN TO THE NORTH BAY FIRST THEN DOWN TO THE SF BAY
REGION LATE IN THE EVENING. THE RAIN WILL CONTINUE TO PROGRESS TO
THE SOUTH AND EAST OVERNIGHT WITH SAN JOSE AND MONTEREY BOTH
LOOKING AT START TIMES FOR PRECIPITATION AT OR JUST AFTER MIDNIGHT.
RAIN WILL SWITCH OVER TO SCATTERED SHOWERS BY LATE SATURDAY
MORNING. RAINFALL TOTALS WILL GENERALLY BE UNDER 1/3" FOR URBAN
SPOTS WITH LOCALLY 1/2" TO 1" IN THE COASTAL RANGES. HRRR DOES
INDICATE MORE WIDESPREAD LIGHT RAINFALL COMPARED TO YESTERDAY`S
SYSTEM, SO LOCATIONS THAT WERE DRY OR JUST GOT A TRACE YESTERDAY
SHOULD DO A BIT BETTER.
SUNDAY WILL START OUT GENERALLY DRY BEFORE THE MAIN SYSTEM OF THE
SERIES ADVANCES INTO THE REGION BEGINNING SUNDAY EVENING. MODELS
REMAIN IN FAIRLY GOOD AGREEMENT THAT RAIN WILL MOVE BACK TO THE
NORTH BAY IN THE EVENING AND THEN DOWN TO SF BAY AND MONTEREY BAY
REGION FOR THE OVERNIGHT HOURS. RAINFALL WILL LIKELY BE MODERATE
TO HEAVY AT TIMES AS THE FRONT GOES THROUGH THANKS IN PART TO PW
VALUES NEAR 1.3". ON THE POSITIVE SIDE, IT LOOKS LIKE THE HEAVIEST RAINFALL
WILL LIKELY COINCIDE WITH THE NIGHT BEFORE MLK HOLIDAY SUGGESTING
THAT TRAFFIC SHOULD BE AT EXTREMELY LOW LEVELS. RAINFALL TOTALS
WILL GENERALLY BE 1/2" TO 1" IN MANY URBAN SPOTS WITH 1-3" AT
COASTAL RANGES (ISOLATED 4+"). THE OTHER STORY WITH THIS SYSTEM
WILL BE LOCALLY GUSTY SOUTHERLY WINDS JUST AHEAD OF THE FRONT.
SOUTHERLY WINDS OF 15 TO 25 MPH GUSTING TO 35 MPH CAN BE EXPECTED
SUNDAY AFTERNOON INTO THE EVENING.
RAIN WILL AGAIN SWITCH TO SHOWERS WITH JUST LIGHT PRECIPITATION
EXPECTED FOR MONDAY AFTERNOON.
PREVIOUS MODEL GUIDANCE INDICATED A SECOND SLUG OF MOISTURE POISED
TO MOVE THROUGH LAST MONDAY INTO TUESDAY. HOWEVER THAT NOW APPEARS
MUCH LESS LIKELY BASED OFF OF THE ENSEMBLE PLUS MOST OPERATIONAL
MODELS. NOW APPEARS THAT INSTEAD A SHORTWAVE WILL MOVE TO THE PAC
NW COAST TUESDAY EVENING/NIGHT AND BRING SOME MORE LIGHT RAIN TO
OUR REGION. SINCE THIS WAS A HUGE CHANGE FROM THE PREVIOUS
PACKAGE, POPS AND QPF WERE BOTH GREATLY REDUCED FOR MONDAY NIGHT
INTO TUESDAY. HOWEVER, DID NOT FEEL COMFORTABLE GOING COMPLETELY
DRY WHICH SOME OF THE MODELS ARE NOW INDICATING. BOTTOM
LINE...MONDAY NIGHT INTO TUESDAY CURRENTLY LOOKS LIKE A NON-EVENT
WITH JUST LIGHT RAIN POSSIBLE IN THE WORST CASE.
BEYOND TUESDAY, ACTIVE PATTERN IS EXPECTED TO CONTINUE THROUGH
THE END OF THE MONTH.
&&
.AVIATION...AS OF 10:00 AM PST FRIDAY...FOR 18Z TAFS. VFR TODAY
WITH PREDOMINATELY LIGHT SOUTHEAST WINDS. APPROACHING STORM SYSTEM
WILL BRING RAIN TO THE AREA FROM NORTHWEST TO SOUTHEAST BTWN 03Z
SAT THROUGH 15Z SAT... THEN LINGERING RAIN SHOWERS THROUGH 03Z
SUN. CIGS WILL DETERIORATE INTO MVFR RANGE EARLY IN THE EVENT...
AND DROP INTO IFR RANGE FOR SOME LOCATIONS AFTER 10-12Z SAT AND
REMAIN IN IFR-MVFR RANGE THROUGH SATURDAY MORNING. PREDOMINATELY
SOUTH TO SOUTHEAST WINDS WILL PREVAIL THROUGH THE TAF PERIOD...
WITH BRIEF VARIABLE SHIFTS TO OTHER DIRECTIONS.
VICINITY OF KSFO... VFR THROUGH 03Z SAT... THEN DETERIORATING CIGS
DOWN TO MVFR RANGE THROUGH REMAINDER OF TAF PERIOD. RA TO SHRA
FROM 05Z THROUGH END OF TAF PERIOD. PREDOMINATELY EAST WINDS
THROUGH THE MORNING THEN SOUTHEAST WINDS WILL PREVAIL THROUGH
MIDDAY SATURDAY. HEAVIEST RAIN CURRENTLY EXPECTED BETWEEN 06-10Z
SAT.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...VFR CIGS WITH LIGHT VARIABLE WINDS
THROUGH THE DAYLIGHT HOURS. LIGHT SOUTHEAST WINDS AND INCREASING
MID CLOUDS BEGINNING AROUND 05-06Z SAT THEN DETERIORATING CIGS TO
MVFR/IFR RANGE AFTER 08-10Z. HEAVIEST RAIN SLOTTED BETWEEN 08-011Z
SAT.
&&
.MARINE...AS OF 11:38 AM PST FRIDAY...LIGHT VARIABLE WINDS THROUGH
EARLY THIS AFTERNOON. WINDS INCREASE AND SHIFT TO BECOME SOUTHERLY
LATER THIS AFTERNOON AND INTO THIS EVENING AHEAD OF AN APPROACHING
FRONT. THE STRONGEST WINDS WILL BE OVER THE NORTHERN OUTER WATERS
THROUGH SATURDAY. BY SATURDAY AFTERNOON A LARGE AND LONG PERIOD
SWELL TRAIN WILL SPREAD THROUGH THE WATERS WITH LARGE SEAS AND
SOUTHERLY WINDS THROUGH THE REST OF THE WEEKEND AS MORE STRONG
STORMS TAKE AIM TOWARDS CAPE MENDOCINO.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TNGT...SCA...PT ARENA TO PIGEON PT 10-60 NM
SCA...PT ARENA TO PT REYES 0-10 NM FROM 1 AM
SCA...PT REYES TO PIGEON PT 0-10 NM FROM 2 AM
&&
$$
PUBLIC FORECAST: BELL
AVIATION: DRP
MARINE: DRP
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AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
915 PM CST SAT JAN 16 2016
.UPDATE...
ISSUED AT 910 PM CST SAT JAN 16 2016
The arctic front is progressing southeast across IL, with a band
of flurries developing along the front northwest of a line from
Rushville to Lincoln to Bloomington at 03z/9pm. The 00z ILX
sounding showed some dry air to overcome, so the radar returns may
be mostly virga at this point. Have added flurries to follow the
band of radar returns as it progresses farther southeast. The
initial period of snow is expected to dissipate according to HRRR
and RAP output, with another wave of snow developing with an upper
level wave moving east along the front. High res models show that
wave of snow will be mainly in our western counties, with somewhat
limited eastward extent. Have delayed the coverage of chance PoPs
with the second wave, and lowered the extent of the 50 pct PoPs.
A dusting of snow still could develop in a few locations, but the
increasing wind will likely push most of that snow off area roads.
Updates this evening were mainly needed for the weather and PoP
grids. Temps and winds look on track, so will not make any
adjustments to the wind chill advisory for our NW
counties...mainly NW of the IL river. Updated forecast info is
already available.
&&
.SHORT TERM...(Tonight)
ISSUED AT 255 PM CST SAT JAN 16 2016
A surge of bitterly cold air is on the way later tonight...as a
1033mb high over Saskatchewan builds southward into the central U.S.
An area of lift ahead of the colder airmass associated with a weak
mid-level short-wave is spreading across eastern Nebraska into
western/central Iowa, where light snow is currently falling. Models
show this lift gradually developing eastward into central Illinois
later this evening into the overnight hours. Airmass will initially
be quite dry at mid/low-levels, so it will take awhile for any
precip to develop. Based on time-height cross-sections, it appears
strongest lift and deepest column moisture will only be present for
a 3-4 hour window from just after midnight into Sunday morning. Have
therefore kept conditions dry through the evening, with high chance
PoPs for light snow developing along/north of the I-72 corridor
after midnight. Accumulations will be minor due to the light and
transient nature of the precip, with amounts of one half inch or
less anticipated. Main weather story will be the breezy and colder
conditions, as overnight lows drop into the single digits and teens.
Corresponding wind-chill values will drop below zero along/north of
I-72 by dawn Sunday...with the coldest readings of near 15 below
zero across the NW KILX CWA. Have issued a Wind Chill Advisory
along and north of a Lewistown to El Paso line...and a Special
Weather Statement highlighting the cold further southeast to I-72.
.LONG TERM...(Sunday through Saturday)
ISSUED AT 255 PM CST SAT JAN 16 2016
A weak wave will continue to move across the area Sunday morning,
with light amounts of snowfall expected. Due to the weak lift and
limited moisture, will continue with just chance pops for the
morning only and then have dry weather with skies clearing out in
the afternoon. This dry weather will continue thru the rest of the
weekend holiday and into Monday night. Then clouds will begin to
increase on Tuesday as the next weather system approaches from the
west. The mid range models are in very good agreement with this next
system with snow expected Tue afternoon through Wed morning/early
afternoon. Based on timing of the low pressure area the best chance
of snow will be Tuesday night and in southwest IL. Though this
system is stronger than the one coming in tonight and it will have
more moisture to work with, it doesn`t appear that much snow will
occur with this system. A couple of inches will be possible, but
over a period of 24-30hrs. Another weather system is possible on the
heals of the system that will be leaving the area Wed. However,
models showing disagreement with track of low pressure area, which
effects the location and timing of pcpn. ECMWF takes the sfc low
well south, into the Gulf Coastal area and moves it east across FL.
The GFS and Canadian are in agreement with each other and bring the
sfc low out of OK, through southern MO, and into southern IL. This
track would spread more pcpn/snow across the CWA for the later part
of the week. So will continue with a blend of models with this end
of week system and have chance pops only Thur night across areas
east of the IL river, only. Will have just snow in the forecast for
now, but this looks like an over-running situation, so a wintry mix
of pcpn is not out of the question. New forecasts early next week
should give us a better idea on location and pcpn type.
Temps will be very cold tonight and tomorrow night. Wind chill
advisory for tonight will continue til tomorrow late morning in the
northwest. However, with temps expected to be even colder tomorrow
night/Mon morning, another advisory is likely and will probably
cover the entire CWA. Temps will gradually warm next week and could
reach to normal by next Sat.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 600 PM CST SAT JAN 16 2016
23z/5pm satellite imagery and surface obs show that skies have
cleared at all terminal sites except CMI, where MVFR ceilings will
clear just before 00z. After a period of clear conditions, an
approaching cold front will spread clouds and a few snow- showers
into the area from the northwest this evening. The 1km NAMNEST is
handling the band of light snow just north of Peoria quite well.
It shows a period of light snow from that initial band for PIA by
02z, and BMI by 03z, with a break after that snow from 07z-10z or
so. Then another band of snow is expected to develop, which the
RAP and HRRR are both showing for later tonight. Time height cross
sections show plenty of moisture during the break, so a few
flurries could linger between waves, despite limited lift during
that time. So have included a mention of snow about 4 hours
earlier than the previous TAFs, but will still keep conditions
only down to MVFR and not introduce any IFR vis or ceilings. A
dusting to as much as a half inch of fluffy snow will be possible.
Snowfall should end shortly after sunrise as the very dry airmass
arrives on brisk NW winds.
Winds will shift from W to NW after the passage of the arctic
front, with speeds increasing later tonight as pressure rises ramp
up in the wake of the front. By 12z, winds could already be
gusting to 25kt in PIA, with those gusts advancing to CMI/DEC by
14z.
Skies will quickly clear from the northwest Sunday morning as
well, with clear conditions at all TAF sites by early Sunday
afternoon.
&&
.ILX Watches/Warnings/Advisories...
Wind Chill Advisory from 3 AM to 11 AM CST Sunday for ILZ027>031-
036-037.
&&
$$
UPDATE...Shimon
SHORT TERM...Barnes
LONG TERM...Auten
AVIATION...Shimon
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
602 PM CST SAT JAN 16 2016
.SHORT TERM...(Tonight)
ISSUED AT 255 PM CST SAT JAN 16 2016
A surge of bitterly cold air is on the way later tonight...as a
1033mb high over Saskatchewan builds southward into the central U.S.
An area of lift ahead of the colder airmass associated with a weak
mid-level short-wave is spreading across eastern Nebraska into
western/central Iowa, where light snow is currently falling. Models
show this lift gradually developing eastward into central Illinois
later this evening into the overnight hours. Airmass will initially
be quite dry at mid/low-levels, so it will take awhile for any
precip to develop. Based on time-height cross-sections, it appears
strongest lift and deepest column moisture will only be present for
a 3-4 hour window from just after midnight into Sunday morning. Have
therefore kept conditions dry through the evening, with high chance
PoPs for light snow developing along/north of the I-72 corridor
after midnight. Accumulations will be minor due to the light and
transient nature of the precip, with amounts of one half inch or
less anticipated. Main weather story will be the breezy and colder
conditions, as overnight lows drop into the single digits and teens.
Corresponding wind-chill values will drop below zero along/north of
I-72 by dawn Sunday...with the coldest readings of near 15 below
zero across the NW KILX CWA. Have issued a Wind Chill Advisory
along and north of a Lewistown to El Paso line...and a Special
Weather Statement highlighting the cold further southeast to I-72.
.LONG TERM...(Sunday through Saturday)
ISSUED AT 255 PM CST SAT JAN 16 2016
A weak wave will continue to move across the area Sunday morning,
with light amounts of snowfall expected. Due to the weak lift and
limited moisture, will continue with just chance pops for the
morning only and then have dry weather with skies clearing out in
the afternoon. This dry weather will continue thru the rest of the
weekend holiday and into Monday night. Then clouds will begin to
increase on Tuesday as the next weather system approaches from the
west. The mid range models are in very good agreement with this next
system with snow expected Tue afternoon through Wed morning/early
afternoon. Based on timing of the low pressure area the best chance
of snow will be Tuesday night and in southwest IL. Though this
system is stronger than the one coming in tonight and it will have
more moisture to work with, it doesn`t appear that much snow will
occur with this system. A couple of inches will be possible, but
over a period of 24-30hrs. Another weather system is possible on the
heals of the system that will be leaving the area Wed. However,
models showing disagreement with track of low pressure area, which
effects the location and timing of pcpn. ECMWF takes the sfc low
well south, into the Gulf Coastal area and moves it east across FL.
The GFS and Canadian are in agreement with each other and bring the
sfc low out of OK, through southern MO, and into southern IL. This
track would spread more pcpn/snow across the CWA for the later part
of the week. So will continue with a blend of models with this end
of week system and have chance pops only Thur night across areas
east of the IL river, only. Will have just snow in the forecast for
now, but this looks like an over-running situation, so a wintry mix
of pcpn is not out of the question. New forecasts early next week
should give us a better idea on location and pcpn type.
Temps will be very cold tonight and tomorrow night. Wind chill
advisory for tonight will continue til tomorrow late morning in the
northwest. However, with temps expected to be even colder tomorrow
night/Mon morning, another advisory is likely and will probably
cover the entire CWA. Temps will gradually warm next week and could
reach to normal by next Sat.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 600 PM CST SAT JAN 16 2016
23z/5pm satellite imagery and surface obs show that skies have
cleared at all terminal sites except CMI, where MVFR ceilings will
clear just before 00z. After a period of clear conditions, an
approaching cold front will spread clouds and a few snow- showers
into the area from the northwest this evening. The 1km NAMNEST is
handling the band of light snow just north of Peoria quite well.
It shows a period of light snow from that initial band for PIA by
02z, and BMI by 03z, with a break after that snow from 07z-10z or
so. Then another band of snow is expected to develop, which the
RAP and HRRR are both showing for later tonight. Time height cross
sections show plenty of moisture during the break, so a few
flurries could linger between waves, despite limited lift during
that time. So have included a mention of snow about 4 hours
earlier than the previous TAFs, but will still keep conditions
only down to MVFR and not introduce any IFR vis or ceilings. A
dusting to as much as a half inch of fluffy snow will be possible.
Snowfall should end shortly after sunrise as the very dry airmass
arrives on brisk NW winds.
Winds will shift from W to NW after the passage of the arctic
front, with speeds increasing later tonight as pressure rises ramp
up in the wake of the front. By 12z, winds could already be
gusting to 25kt in PIA, with those gusts advancing to CMI/DEC by
14z.
Skies will quickly clear from the northwest Sunday morning as
well, with clear conditions at all TAF sites by early Sunday
afternoon.
&&
.ILX Watches/Warnings/Advisories...
Wind Chill Advisory from 3 AM to 11 AM CST Sunday for ILZ027>031-
036-037.
&&
$$
SHORT TERM...Barnes
LONG TERM...Auten
AVIATION...Shimon
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
228 PM CST FRI JAN 15 2016
.SHORT TERM...(Tonight)
ISSUED AT 228 PM CST FRI JAN 15 2016
20z/2pm surface analysis shows cold front pushing east of the I-57
corridor, as the area of rain ahead of the boundary exits into
Indiana. While temperatures are still in the lower to middle 40s
across the E/SE KILX CWA, readings have dropped into the lower to
middle 30s further west across the remainder of the area.
Temperatures will continue to fall over the next couple of hours,
with readings ranging from the upper 20s in the Illinois River
Valley...to the upper 30s across the far SE around Lawrenceville by
early evening. Latest satellite imagery shows plenty of clouds
upstream across central/eastern Iowa, with the closest appreciable
clearing over western sections of Minnesota/Iowa. HRRR shows this
clear spot shifting southeastward and remaining W/SW of the CWA
tonight. Further north, HRRR is hinting that some breaks in the
overcast will develop across Wisconsin later tonight: however, any
clearing from the north will likely not occur until Saturday
morning. As a result, am going with a cloudy forecast tonight, with
a few flurries possible along/north of I-72 during the evening.
Overnight low temperatures will range from the teens northwest of
the Illinois River to the upper 20s southeast of I-70.
&&
.LONG TERM...(Saturday through Friday)
ISSUED AT 228 PM CST FRI JAN 15 2016
Large high pressure ridge will move into the area and affect the CWA
beginning tomorrow. However, a clipper system will move toward the
area tomorrow evening and then into the CWA late tomorrow night. The
snow will push into the northwest parts of the CWA and then spread
east southeast across the remainder of the CWA Sunday morning. If
any area of the CWA does not get snow, it will be in southeast IL.
Northwest winds will be a tad breezy on Sunday as this clipper
system pushes east and out of the area. Dry weather is then expected
through Mon night with cold high pressure dominating the weather
pattern at the end of the weekend and into the beginning of next
week.
Temps will become very cold this weekend as the cold air associated
with the high pressure pours into the area this weekend. Temps will
drop into the single digits along and northwest of the IL river for
Sat night, with wind chills in the range of -10 to -15, which is
close to wind chill advisory. Temps will get much colder Sun night
into Mon morning, with low temps in the single digits in southeast
IL and below zero over the remainder of the CWA, north of I-70.
Combined with the wind, resulting wind chills Sun night will range
from 15 to 25 degrees below zero over most of the area...which is
wind chill advisory criteria.
Another clipper-type weather system will move across the area Tue
thru Wed and produce another round of light snow in the area. Models
differ on speed/timing of this system but appears that most of the
snow will be on Tue night and Wed. After this system moves through,
ECMWF and GFS agree that any additional systems will get pushed
further south leaving the CWA dry from Wed night through Fri.
However, the Canadian model brings another clipper system through
the area mid week with more snow, which agreed with some older model
runs. Blend of the models gives more chance pops, but prefer better
agreement of the ECMWF and GFS. So for now, will just lower pops to
slight chance for Wed night thru Fri; though thinking is that a dry
forecast is what will be seen in later forecasts.
Temps will start cold with Mon night temps remaining well below
normal. Then temps gradually warm back up but not reaching normal
through end of the week. Extended model guidance does not look that
bad, but kept a degree or two below guidance for now.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
ISSUED AT 1152 AM CST FRI JAN 15 2016
Cold front continues to push eastward late this morning, with
latest obs showing it approaching the I-57 corridor. Southwesterly
winds and rain will persist at KCMI through 19z before the front
passes and winds veer to the northwest. Despite FROPA, low clouds
blanket the region westward into Iowa/Minnesota. Ceilings are
generally low MVFR: however, an area of IFR ceilings is noted
across eastern Iowa into west-central Illinois. Based on satellite
timing tools and to a lesser extent the HRRR forecast, have
introduced a period of IFR at KPIA and KSPI through the 21z/22z
time frame. After that, GFS forecast soundings suggest MVFR
ceilings of around 1500ft will prevail from late afternoon through
the night. Big question will be how fast to clear things off on
Saturday. NAM appears to be suffering from its usual low-level
moist bias within the strong CAA regime, so have trended toward
the GFS. As such, have scattered clouds at KPIA by 14z, but have
maintained overcast conditions further east at KCMI through 18z
Sat.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Auten
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1152 AM CST FRI JAN 15 2016
.UPDATE...
ISSUED AT 1048 AM CST FRI JAN 15 2016
16z/10am surface analysis shows cold front along the I-55
corridor, with an area of light to moderate rain occurring ahead
of the front across much of the eastern KILX CWA. Based on 12z
NAM/HRRR, it appears the front will clear the eastern CWA by
21z/3pm. Have increased PoPs to categorical ahead of the front
and have fine-tuned the timing of precip departure this afternoon.
Once the front passes, winds veer to the W/NW and temperatures
drop abruptly. Temperatures have fallen into the upper 20s and
lower 30s west of the Illinois River...and this colder air will
push eastward across the remainder of the area this afternoon.
Highs will mainly be in the lower to middle 40s, although a few
readings near 50 degrees will be possible across the SE counties
before temps fall after FROPA. Have noted a few snow
flurries/snow-showers upstream across central and northern Iowa
and think these will spread into north-central Illinois this
afternoon. HRRR hints at this as well, so have added scattered
flurries to the forecast along/north of a Rushville to Bloomington
line later today.
&&
.SHORT TERM...(Today)
ISSUED AT 229 AM CST FRI JAN 15 2016
Latest surface analysis had low pressure centered over southwest
Wisconsin, with the trailing cold front extending southwest into the
southern Plains. The low is forecast to reach eastern Michigan by
this evening, with the cold front expected to be east of the forecast
area by mid-afternoon. The front is strong temperature-wise, and
temperatures will be falling in its wake. This will result in high
temperatures being reached early this morning across west-central
Illinois, with temperatures likely falling for the rest of the day.
The biggest question with respect the front is if it will provide
precipitation across central and southeast Illinois. The airmass the
front is moving into is quite dry per 00Z ILX and forecast
soundings. This is also shown by the significant lack of cloud cover
showing up in local surface observations (clouds below 12K feet).
The only nearby rainfall at the moment is a thin line of showers
along the front in Missouri. Model guidance continues to suggest
that the rainfall will expand within the pre-frontal WAA/isentropic
lift. However, there is not much time for moistening to occur before
FROPA across at least the western portion of the forecast area.
Still expect at least a few hour period of rain across the eastern
portion of the forecast area, mainly before noon, but significant
rainfall is not anticipated. Forecast soundings suggest the
precipitation will cut off before temperatures are cold enough for
snow.
.LONG TERM...(Tonight through Thursday)
ISSUED AT 229 AM CST FRI JAN 15 2016
Next lobe of Arctic air poised to start its southward push,
associated with a large upper low currently just north of Lake
Winnipeg. More recent model runs are a bit slower in getting the
core of the cold air mass this far south, with the strongest surge
taking place Sunday as 850 mb temps drop to around -21C. Thus, made
some adjustments with the temperatures for Saturday night and Sunday
by bringing them up a few degrees, which will lessen the risk of
needing a wind chill advisory as early as Saturday night. Sunday
night still looking to be the coldest, with wind chills of -15F as
far south as I-70 and many areas seeing lows below zero.
In regards to the weekend snow threat, with the upper low itself a
bit delayed in arriving, have backed off some with the snow chances
late Saturday night and mainly limited them northwest of the
Illinois River. Main threat will be Sunday morning, but the window
of opportunity appears to be shrinking as most of the models
diminish the amount of precip accumulation as the wave passes
through. Thus, left PoP`s generally in the 30% range for now, with
some slight chances lingering across the southeast half of the CWA
into afternoon.
Longer range remains a bit challenging as the Arctic air mass exits.
The latest ECMWF now suggests mainly a Tuesday night-Wednesday
morning event with the wave that will be dropping out of the
Dakotas, while the GFS a more pronounced and longer-lasting system
due to a more prominent upper trough extending south into Texas.
This results in that model featuring a broad trough and cooler air
persisting into mid week, while the ECMWF quickly warms ahead of the
late week system. Model performance this far out has not been
consistent as of late, leading to lower confidence for the forecast
details beyond Wednesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
ISSUED AT 1152 AM CST FRI JAN 15 2016
Cold front continues to push eastward late this morning, with
latest obs showing it approaching the I-57 corridor. Southwesterly
winds and rain will persist at KCMI through 19z before the front
passes and winds veer to the northwest. Despite FROPA, low clouds
blanket the region westward into Iowa/Minnesota. Ceilings are
generally low MVFR: however, an area of IFR ceilings is noted
across eastern Iowa into west-central Illinois. Based on satellite
timing tools and to a lesser extent the HRRR forecast, have
introduced a period of IFR at KPIA and KSPI through the 21z/22z
time frame. After that, GFS forecast soundings suggest MVFR
ceilings of around 1500ft will prevail from late afternoon through
the night. Big question will be how fast to clear things off on
Saturday. NAM appears to be suffering from its usual low-level
moist bias within the strong CAA regime, so have trended toward
the GFS. As such, have scattered clouds at KPIA by 14z, but have
maintained overcast conditions further east at KCMI through 18z
Sat.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...BAK
LONG TERM...Geelhart
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1048 AM CST FRI JAN 15 2016
.UPDATE...
ISSUED AT 1048 AM CST FRI JAN 15 2016
16z/10am surface analysis shows cold front along the I-55
corridor, with an area of light to moderate rain occurring ahead
of the front across much of the eastern KILX CWA. Based on 12z
NAM/HRRR, it appears the front will clear the eastern CWA by
21z/3pm. Have increased PoPs to categorical ahead of the front
and have fine-tuned the timing of precip departure this afternoon.
Once the front passes, winds veer to the W/NW and temperatures
drop abruptly. Temperatures have fallen into the upper 20s and
lower 30s west of the Illinois River...and this colder air will
push eastward across the remainder of the area this afternoon.
Highs will mainly be in the lower to middle 40s, although a few
readings near 50 degrees will be possible across the SE counties
before temps fall after FROPA. Have noted a few snow
flurries/snow-showers upstream across central and northern Iowa
and think these will spread into north-central Illinois this
afternoon. HRRR hints at this as well, so have added scattered
flurries to the forecast along/north of a Rushville to Bloomington
line later today.
&&
.SHORT TERM...(Today)
ISSUED AT 229 AM CST FRI JAN 15 2016
Latest surface analysis had low pressure centered over southwest
Wisconsin, with the trailing cold front extending southwest into the
southern Plains. The low is forecast to reach eastern Michigan by
this evening, with the cold front expected to be east of the forecast
area by mid-afternoon. The front is strong temperature-wise, and
temperatures will be falling in its wake. This will result in high
temperatures being reached early this morning across west-central
Illinois, with temperatures likely falling for the rest of the day.
The biggest question with respect the front is if it will provide
precipitation across central and southeast Illinois. The airmass the
front is moving into is quite dry per 00Z ILX and forecast
soundings. This is also shown by the significant lack of cloud cover
showing up in local surface observations (clouds below 12K feet).
The only nearby rainfall at the moment is a thin line of showers
along the front in Missouri. Model guidance continues to suggest
that the rainfall will expand within the pre-frontal WAA/isentropic
lift. However, there is not much time for moistening to occur before
FROPA across at least the western portion of the forecast area.
Still expect at least a few hour period of rain across the eastern
portion of the forecast area, mainly before noon, but significant
rainfall is not anticipated. Forecast soundings suggest the
precipitation will cut off before temperatures are cold enough for
snow.
.LONG TERM...(Tonight through Thursday)
ISSUED AT 229 AM CST FRI JAN 15 2016
Next lobe of Arctic air poised to start its southward push,
associated with a large upper low currently just north of Lake
Winnipeg. More recent model runs are a bit slower in getting the
core of the cold air mass this far south, with the strongest surge
taking place Sunday as 850 mb temps drop to around -21C. Thus, made
some adjustments with the temperatures for Saturday night and Sunday
by bringing them up a few degrees, which will lessen the risk of
needing a wind chill advisory as early as Saturday night. Sunday
night still looking to be the coldest, with wind chills of -15F as
far south as I-70 and many areas seeing lows below zero.
In regards to the weekend snow threat, with the upper low itself a
bit delayed in arriving, have backed off some with the snow chances
late Saturday night and mainly limited them northwest of the
Illinois River. Main threat will be Sunday morning, but the window
of opportunity appears to be shrinking as most of the models
diminish the amount of precip accumulation as the wave passes
through. Thus, left PoP`s generally in the 30% range for now, with
some slight chances lingering across the southeast half of the CWA
into afternoon.
Longer range remains a bit challenging as the Arctic air mass exits.
The latest ECMWF now suggests mainly a Tuesday night-Wednesday
morning event with the wave that will be dropping out of the
Dakotas, while the GFS a more pronounced and longer-lasting system
due to a more prominent upper trough extending south into Texas.
This results in that model featuring a broad trough and cooler air
persisting into mid week, while the ECMWF quickly warms ahead of the
late week system. Model performance this far out has not been
consistent as of late, leading to lower confidence for the forecast
details beyond Wednesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 558 AM CST FRI JAN 15 2016
CIGS will gradually lower to MVFR, or possibly IFR, today as a
cold front pushes into the area and low-level moisture increases.
A few rain showers are possible ahead of the front, but
significant precipitation is not anticipated. Winds will swing
around to the west-northwest behind the front later today and
become gusty for several hours.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...BAK
LONG TERM...Geelhart
AVIATION...BAK
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
230 AM CST FRI JAN 15 2016
.SHORT TERM...(Today)
ISSUED AT 229 AM CST FRI JAN 15 2016
Latest surface analysis had low pressure centered over southwest
Wisconsin, with the trailing cold front extending southwest into the
southern Plains. The low is forecast to reach eastern Michigan by
this evening, with the cold front expected to be east of the forecast
area by mid-afternoon. The front is strong temperature-wise, and
temperatures will be falling in its wake. This will result in high
temperatures being reached early this morning across west-central
Illinois, with temperatures likely falling for the rest of the day.
The biggest question with respect the front is if it will provide
precipitation across central and southeast Illinois. The airmass the
front is moving into is quite dry per 00Z ILX and forecast
soundings. This is also shown by the significant lack of cloud cover
showing up in local surface observations (clouds below 12K feet).
The only nearby rainfall at the moment is a thin line of showers
along the front in Missouri. Model guidance continues to suggest
that the rainfall will expand within the pre-frontal WAA/isentropic
lift. However, there is not much time for moistening to occur before
FROPA across at least the western portion of the forecast area.
Still expect at least a few hour period of rain across the eastern
portion of the forecast area, mainly before noon, but significant
rainfall is not anticipated. Forecast soundings suggest the
precipitation will cut off before temperatures are cold enough for
snow.
&&
.LONG TERM...(Tonight through Thursday)
ISSUED AT 229 AM CST FRI JAN 15 2016
Next lobe of Arctic air poised to start its southward push,
associated with a large upper low currently just north of Lake
Winnipeg. More recent model runs are a bit slower in getting the
core of the cold air mass this far south, with the strongest surge
taking place Sunday as 850 mb temps drop to around -21C. Thus, made
some adjustments with the temperatures for Saturday night and Sunday
by bringing them up a few degrees, which will lessen the risk of
needing a wind chill advisory as early as Saturday night. Sunday
night still looking to be the coldest, with wind chills of -15F as
far south as I-70 and many areas seeing lows below zero.
In regards to the weekend snow threat, with the upper low itself a
bit delayed in arriving, have backed off some with the snow chances
late Saturday night and mainly limited them northwest of the
Illinois River. Main threat will be Sunday morning, but the window
of opportunity appears to be shrinking as most of the models
diminish the amount of precip accumulation as the wave passes
through. Thus, left PoP`s generally in the 30% range for now, with
some slight chances lingering across the southeast half of the CWA
into afternoon.
Longer range remains a bit challenging as the Arctic air mass exits.
The latest ECMWF now suggests mainly a Tuesday night-Wednesday
morning event with the wave that will be dropping out of the
Dakotas, while the GFS a more pronounced and longer-lasting system
due to a more prominent upper trough extending south into Texas.
This results in that model featuring a broad trough and cooler air
persisting into mid week, while the ECMWF quickly warms ahead of the
late week system. Model performance this far out has not been
consistent as of late, leading to lower confidence for the forecast
details beyond Wednesday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday night)
ISSUED AT 1148 PM CST THU JAN 14 2016
Relatively dry air in place across central IL will slow down the
development of MVFR cloud conditions and light rain later tonight.
The low levels will see the increasing moisture primarily, with
deep layer moisture developing toward 15z and mainly east of I-55,
ahead of an approaching cold front. Still seeing an overall delay
in the start of rain, but spotty showers or drizzle could begin as
early as 10z-12z. Profiles never become saturated through a deep
layer, even in the east, so contemplated keeping only a mention
VCSH with the front. However, decided to go with the actual precip
type to outline the progression of when rain will change to snow,
if precip does occur.
The HRRR and NAM/GFS soundings still point toward a period of IFR
clouds during the FROPA hours. Will continue to include IFR cloud
heights at all terminal sites for the mid morning to late
afternoon time frame. Once the boundary pushes east, gusty
southerly winds will veer to the west Friday morning, then NW
and increasing to 15-20kt Fri afternoon and evening. FROPA timing
appears to be about 16z at KPIA and closer to 18z at KCMI. While
sustained surface winds will remain quite brisk at around 12-20kt
tonight, radar VWP plots and the NAM are showing a strong 45-50kt
925mb jet ongoing. Have therefore continued to include low-level
wind shear at the TAF sites the rest of tonight.
As for precip type, decided to introduce light snow in the
afternoon, transitioning first near PIA by 18z, then advancing
eastward to CMI and DEC by late afternoon. Snow accumulation
potential is low, due to limited moisture after the change over to
snow occurs.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...BAK
LONG TERM...Geelhart
AVIATION...Shimon
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1148 PM CST THU JAN 14 2016
.UPDATE...
ISSUED AT 900 PM CST THU JAN 14 2016
The 00z KILX sounding indicated very dry air in place across
central Illinois this evening. Even an upstream 00z sounding at
KSGF, Springfield Missouri, showed similarly dry conditions. The
HRRR and RAP models have been progressively slowing down the onset
of any precipitation across central Illinois, as have the NAM12
and namdng but to a lesser extent. Satellite loops are showing the
upstream shortwave in eastern Texas and Arkansas may take a track
that would focus our forcing for precip later tonight and Friday
to areas east of I-55. The passage of the cold front in
conjunction with the arrival of upper level energy will put the
better chances of rain mainly from mid morning into early
afternoon, before the front departs into Indiana.
Have updated the PoP and weather grids to slow down the onset of
rain overnight, with only slight chances of precip before 12z.
Also reduced the areal coverage of likely PoPs Friday morning
closer to the I-57 corridor and areas east of there.
The arrival of colder air will be late enough in the event to
limit the potential of accumulating snowfall, and mainly north of
I-74.
Temperatures overnight will likely remain much above normal under
the continued mild southwest flow. A few strong wind gusts could
continue to show up as well, with a 50kt LLJ just above the
ground, and marginal decoupling of the boundary layer this
evening.
Updated forecast info is already available.
&&
.SHORT TERM...(Tonight)
ISSUED AT 322 PM CST THU JAN 14 2016
20z/2pm surface analysis shows 1022mb high anchored over Georgia,
while a 997mb low organizes over eastern South Dakota. The pressure
gradient between these two features will continue to provide a
warm/southerly flow across central Illinois tonight, which will keep
temperatures several degrees warmer than in previous nights. Thanks
to southerly winds of 10 to 15mph through the night and increasing
clouds, overnight low temperatures will remain in the upper 30s and
lower 40s. As the South Dakota low tracks eastward into Wisconsin,
it will pull a cold front toward the region later tonight.
Increasing low-level moisture along/ahead of the boundary will
eventually yield a few light rain showers after midnight. HRRR
suggests the precip will develop along/west of a Champaign to
Taylorville line between 06z and 09z...then will spread further
eastward across the remainder of the area toward dawn. Since
forecast soundings do not fully saturate through a deep layer...will
maintain just chance PoPs overnight until deeper moisture arrives
Friday morning.
.LONG TERM...(Friday through Thursday)
ISSUED AT 322 PM CST THU JAN 14 2016
Models in good agreement with the system that will be moving through
the CWA Friday, as the low pressure area moves across the Great
Lakes with the trailing cold front sliding across the state during
the morning. Once this occurs, much colder air will pour into the
area with temperatures falling during the afternoon hours. During
the day, all the pcpn will be liquid, but when the temps begin to
fall the pcpn will become mixed with snow as it is ending. Do not
see any accumulation of snowfall with this system. Then, after a
brief period of dry weather thru Saturday evening, a clipper system
will move toward the area and bring snow to the area beginning late
Sat night and continuing through Sunday morning. By Sun afternoon,
the snow will have ended and moved east of the area.
Temps will be warm one more day, tomorrow, but then fall beginning
in the afternoon. So, look for morning or late morning highs. Temps
will continue to fall during the night, and then go back up on Sat,
but remain below normal. Then much colder air will pour into the
area for the weekend, with temps below zero in the north Sat night.
Below zero temps are expected again Sun night, but over most of the
area...with only southeast IL seeing above zero temps...though in
the single digits.
Next chance of pcpn will be another clipper system coming toward the
area, but tracking mostly south of the CWA for Tue into Tue night.
Will have a chance of snow in the southwest third of the area for
Tue and then a slight chance of snow over the whole area for Tue
night. Then toward the later half of the week, another weather
system will move toward the area. Models show much disagreement with
this system at this point, so will just go with the blend for now
and have a slight chance of pcpn for Wed night and then a chance
across the southern half of the CWA for Thur. P-type will be mainly
snow in the north, but a mix of rain and snow in the south.
Temps will start cold, but gradually warm back toward normal for Wed
and Thur.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday night)
ISSUED AT 1148 PM CST THU JAN 14 2016
Relatively dry air in place across central IL will slow down the
development of MVFR cloud conditions and light rain later tonight.
The low levels will see the increasing moisture primarily, with
deep layer moisture developing toward 15z and mainly east of I-55,
ahead of an approaching cold front. Still seeing an overall delay
in the start of rain, but spotty showers or drizzle could begin as
early as 10z-12z. Profiles never become saturated through a deep
layer, even in the east, so contemplated keeping only a mention
VCSH with the front. However, decided to go with the actual precip
type to outline the progression of when rain will change to snow,
if precip does occur.
The HRRR and NAM/GFS soundings still point toward a period of IFR
clouds during the FROPA hours. Will continue to include IFR cloud
heights at all terminal sites for the mid morning to late
afternoon time frame. Once the boundary pushes east, gusty
southerly winds will veer to the west Friday morning, then NW
and increasing to 15-20kt Fri afternoon and evening. FROPA timing
appears to be about 16z at KPIA and closer to 18z at KCMI. While
sustained surface winds will remain quite brisk at around 12-20kt
tonight, radar VWP plots and the NAM are showing a strong 45-50kt
925mb jet ongoing. Have therefore continued to include low-level
wind shear at the TAF sites the rest of tonight.
As for precip type, decided to introduce light snow in the
afternoon, transitioning first near PIA by 18z, then advancing
eastward to CMI and DEC by late afternoon. Snow accumulation
potential is low, due to limited moisture after the change over to
snow occurs.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Shimon
SHORT TERM...Barnes
LONG TERM...Auten
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
330 AM EST FRI JAN 15 2016
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 245 PM EST THU JAN 14 2016
A COLD FRONT WILL BRING RAIN TO CENTRAL INDIANA FRIDAY...THEN AN
ARCTIC COLD FRONT WILL BRING SOME SNOW ON SUNDAY ALONG WITH MUCH
COLDER AIR. THE FRIGID AIR WILL LAST UNTIL MID WEEK BEFORE
TEMPERATURES MODERATE SOME. SOME LIGHT SNOW IS POSSIBLE TUESDAY
NIGHT AND AGAIN THURSDAY.
&&
.NEAR TERM /OVERNIGHT|/...
ISSUED AT 933 PM EST THU JAN 14 2016
LOW PRESSURE CENTERED OVER IOWA WAS HELPING TO PROVIDE A WARM AND
SOUTHERLY FLOW OF AIR TO CENTRAL INDIANA AS DEW POINTS HAVE SOARED
INTO THE 30S AND TEMPS WERE HOLDING IN THE 40S. SATELLITE SHOWS
SOME MID AND HIGH CLOUD ACROSS TENNESSEE AND KENTUCKY STREAMING
NORTH TOWARD INDIANA.
GFS 290K SURFACE REVEALS GOOD ISENTROPIC LIFT EXPECTED BY 12Z AS A
SURGE OF MOISTURE ARRIVES WITH SPECIFIC HUMIDITIES OVER 5 G/KG.
TIME HEIGHTS AND FORECAST SOUNDINGS ALSO SHOWING GOOD LOWER LEVEL
SATURATION BY 12Z. HRRR SHOWS PRECIP BREAKING OUT TOWARD 12Z
WITHIN THE ISENTROPIC LIFT. BETTER FORCING WILL ARRIVE AFTER 12Z
AS THE SHORT WAVE OVER THE WESTERN PLAINS ARRIVES IN CENTRAL
INDIANA. THUS WILL CONTINUE THE ONGOING FORECAST OVERNIGHT...WITH
INCREASING CLOUDS AND MAINLY A DRY NIGHT...BUT INCHING POPS UPWARD
AFTER 09Z.
AS FOR TEMPS...HAVE RAISED TEMPS ABOUT 2-3 DEGREES DUE TO EXPECTED
INCREASING CLOUDS ALONG WITH ONGOING WARM AIR ADVECTION.
&&
.SHORT TERM.../FRIDAY THROUGH SUNDAY/
ISSUED AT 245 PM EST THU JAN 14 2016
FOCUS IS ON PRECIPITATION CHANCES EARLY AND LATE IN THE PERIOD.
OVERALL...MODELS ARE SIMILAR WITH THE BIG PICTURE. THERE ARE SOME
TIMING DIFFERENCES WITH THE ARCTIC FRONT SATURDAY NIGHT/SUNDAY
MORNING. THAT FAR OUT...DECIDED A BLEND WOULD STILL WORK OUT BEST
GIVEN THE UNCERTAINTY INVOLVED.
ON FRIDAY AN UPPER TROUGH AND COLD FRONT WILL MOVE INTO THE AREA.
850MB WINDS NEAR 50KT...ISENTROPIC LIFT...AND LARGER SCALE DYNAMICS
FROM THE TROUGH WILL WORK TOGETHER TO PRODUCE RAIN ACROSS THE AREA.
WENT LIKELY OR CATEGORICAL POPS ALL AREAS.
RAIN WILL DIMINISH ACROSS THE WEST DURING THE AFTERNOON BEHIND THE
FRONT...AND TEMPERATURES MAY COOL ENOUGH THERE FOR SOME SNOW TO MIX
IN WITH ANY LINGERING RAIN BY LATE FRIDAY AFTERNOON.
UPPER TROUGH AXIS WILL STILL BE CROSSING THE AREA FRIDAY EVENING AND
CYCLONIC FLOW WILL CONTINUE THROUGH THE NIGHT. THIS SHOULD BE ENOUGH
FOR MAINLY SOME SLIGHT CHANCE POPS THROUGH THE PERIOD. TEMPERATURES
WILL BE COLD ENOUGH FOR SNOW AS THE PRECIPITATION TYPE.
ON SATURDAY THE BULK OF THE MOISTURE WILL MOVE OUT OF THE
AREA...REDUCING THE CHANCES FOR SNOW. CANNOT RULE OUT SOME FLURRIES
/OR PERHAPS FREEZING DRIZZLE IF ENOUGH MOISTURE EXITS ALOFT/. WILL
PUT SOME FLURRIES IN FOR NOW.
ARCTIC FRONT APPROACHES SATURDAY NIGHT AND MOVES THROUGH ON SUNDAY.
WENT WITH SOME SLIGHT CHANCE POPS FAR NORTHWEST LATE IN THE NIGHT TO
ACCOUNT FOR THE POTENTIAL OF THE FRONT REACHING THERE BY 12Z.
EXPECT TYPICAL CONDITIONS TO OCCUR ON SUNDAY WHEN AN ARCTIC FRONT
MOVES THROUGH...SO WENT SCATTERED SNOW SHOWERS ALL AREAS. NAM
INDICATES SNOW SQUALL POTENTIAL IN SOME AREAS...AND MODEL TIME
SECTIONS SHOW PERHAPS SOME WEAK INSTABILITY. THUS SOME OF THE SNOW
SHOWERS COULD BE BRIEFLY HEAVY. HOWEVER OVERALL ACCUMULATION LOOKS
TO BE LESS THAN AN INCH.
GENERALLY STAYED WITH A MODEL BLEND FOR TEMPERATURES THROUGH THE
SHORT TERM.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 255 AM EST FRI JAN 15 2016
A DRY AND BITTER COLD START WILL OCCUR DURING THE LONG TERM AS A COLD
UPPER LOW MOVES EAST ACROSS THE GREAT LAKES. MODELS INDICATE 850 MB
TEMPERATURES NEAR -20 CELSIUS AND SURFACE TEMPERATURES APPROACHING ZERO
ON MONDAY.
HIGH PRESSURE WILL MOVE EAST ACROSS OUR REGION TUESDAY. THE UPPER FLOW
WILL BECOME MORE ZONAL DURING THE 2ND HALF OF THE LONG TERM. HOWEVER A
COUPLE OF SYSTEMS IN THE SOUTHERN STREAM WILL BRING LOW CHANCES OF SNOW
LATE TUESDAY NIGHT INTO WEDNESDAY FOLLOWED BY ANOTHER SYSTEM BRINGING
CHANCE POPS AGAIN WEDNESDAY NIGHT AND THURSDAY. MODEL LOW LEVEL THICKNESS
INDICATE MIXED PRECIPITATION MAY OCCUR OVER SOUTHERN SECTIONS BY THURSDAY...
WHILE MOST OTHER AREAS REMAIN FROZEN.
MADE A FEW TWEAKS TO LOWER MIN TEMPERATURES SLIGHTLY TUESDAY MORNING AND RAISED
MINS SLIGHTLY WEDNESDAY MORNING AND THURSDAY. OTHERWISE...MODEL INITIALIZATION
TEMPERATURES SEEM REASONABLE.
&&
.AVIATION /DISCUSSION FOR THE 150900Z KIND TAF UPDATE/...
ISSUED AT 330 AM EST FRI JAN 15 2016
MINOR TWEAKS MADE TO KIND TAF TO BETTER MATCH CURRENT CONDITIONS.
NO OTHER CHANGES ARE NEEDED AT THIS TIME.
PREVIOUS AVIATION DISCUSSION FOLLOWS...
STRENGTHENING LOW LEVEL SOUTH SOUTHWESTERLY FLOW TONIGHT SHOULD ALLOW FOR
CEILINGS 040-050 CURRENTLY OVER THE LOWER MISSISSIPPI VALLEY TO ADVECT
OVER THE TERMINALS BY 150900Z. THE SUSTAINED WARM/MOIST ADVECTION PATTERN
MAY ALLOW FOR CEILINGS TO FALL INTO THE MVFR CATEGORY TOWARDS/AFTER SUNRISE
ON FRIDAY...AND EVENTUALLY INTO THE IFR CATEGORY BY 151800Z.
ORGANIZED LIFT FROM APPROACHING SYSTEM WILL BEGIN MOVING INTO THE AREA
BY THE LATE MORNING HOURS ON FRIDAY...SO SHOULD SEE AREAS OF RAIN STARTING
TO IMPACT THE TERMINALS FROM THE SOUTHWEST AFTER THAT TIME.
SOME CONCERN FOR LOW LEVEL WIND SHEAR OVERNIGHT AROUND 015 AS A
40-45KT LOW LEVEL JET MOVES THROUGH. AT THIS TIME...IT APPEARS WIND SHEAR
WILL REMAIN JUST BELOW CRITERIA. THREAT FOR LOW LEVEL WIND SHEAR SHOULD
DIMINISH AFTER SUNRISE AS LOW LEVEL JET SHIFTS EAST AND WEAKENS.
SURFACE WINDS GENERALLY 180-200 DEGREES AT 10-13 KTS THROUGH MIDDAY FRIDAY.
MAY BE SOME LOCALIZED SURFACE GUSTS 20-25 KTS OVERNIGHT AS THE LOW LEVEL
JET MAY TEMPORARILY BREAK THE INVERSION.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...PUMA
SHORT TERM...50
LONG TERM...JH
AVIATION...JAS/JH
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
255 AM EST FRI JAN 15 2016
.UPDATE...
LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 245 PM EST THU JAN 14 2016
A COLD FRONT WILL BRING RAIN TO CENTRAL INDIANA FRIDAY...THEN AN
ARCTIC COLD FRONT WILL BRING SOME SNOW ON SUNDAY ALONG WITH MUCH
COLDER AIR. THE FRIGID AIR WILL LAST UNTIL MID WEEK BEFORE
TEMPERATURES MODERATE SOME. SOME LIGHT SNOW IS POSSIBLE TUESDAY
NIGHT AND AGAIN THURSDAY.
&&
.NEAR TERM /OVERNIGHT|/...
ISSUED AT 933 PM EST THU JAN 14 2016
LOW PRESSURE CENTERED OVER IOWA WAS HELPING TO PROVIDE A WARM AND
SOUTHERLY FLOW OF AIR TO CENTRAL INDIANA AS DEW POINTS HAVE SOARED
INTO THE 30S AND TEMPS WERE HOLDING IN THE 40S. SATELLITE SHOWS
SOME MID AND HIGH CLOUD ACROSS TENNESSEE AND KENTUCKY STREAMING
NORTH TOWARD INDIANA.
GFS 290K SURFACE REVEALS GOOD ISENTROPIC LIFT EXPECTED BY 12Z AS A
SURGE OF MOISTURE ARRIVES WITH SPECIFIC HUMIDITIES OVER 5 G/KG.
TIME HEIGHTS AND FORECAST SOUNDINGS ALSO SHOWING GOOD LOWER LEVEL
SATURATION BY 12Z. HRRR SHOWS PRECIP BREAKING OUT TOWARD 12Z
WITHIN THE ISENTROPIC LIFT. BETTER FORCING WILL ARRIVE AFTER 12Z
AS THE SHORT WAVE OVER THE WESTERN PLAINS ARRIVES IN CENTRAL
INDIANA. THUS WILL CONTINUE THE ONGOING FORECAST OVERNIGHT...WITH
INCREASING CLOUDS AND MAINLY A DRY NIGHT...BUT INCHING POPS UPWARD
AFTER 09Z.
AS FOR TEMPS...HAVE RAISED TEMPS ABOUT 2-3 DEGREES DUE TO EXPECTED
INCREASING CLOUDS ALONG WITH ONGOING WARM AIR ADVECTION.
&&
.SHORT TERM.../FRIDAY THROUGH SUNDAY/
ISSUED AT 245 PM EST THU JAN 14 2016
FOCUS IS ON PRECIPITATION CHANCES EARLY AND LATE IN THE PERIOD.
OVERALL...MODELS ARE SIMILAR WITH THE BIG PICTURE. THERE ARE SOME
TIMING DIFFERENCES WITH THE ARCTIC FRONT SATURDAY NIGHT/SUNDAY
MORNING. THAT FAR OUT...DECIDED A BLEND WOULD STILL WORK OUT BEST
GIVEN THE UNCERTAINTY INVOLVED.
ON FRIDAY AN UPPER TROUGH AND COLD FRONT WILL MOVE INTO THE AREA.
850MB WINDS NEAR 50KT...ISENTROPIC LIFT...AND LARGER SCALE DYNAMICS
FROM THE TROUGH WILL WORK TOGETHER TO PRODUCE RAIN ACROSS THE AREA.
WENT LIKELY OR CATEGORICAL POPS ALL AREAS.
RAIN WILL DIMINISH ACROSS THE WEST DURING THE AFTERNOON BEHIND THE
FRONT...AND TEMPERATURES MAY COOL ENOUGH THERE FOR SOME SNOW TO MIX
IN WITH ANY LINGERING RAIN BY LATE FRIDAY AFTERNOON.
UPPER TROUGH AXIS WILL STILL BE CROSSING THE AREA FRIDAY EVENING AND
CYCLONIC FLOW WILL CONTINUE THROUGH THE NIGHT. THIS SHOULD BE ENOUGH
FOR MAINLY SOME SLIGHT CHANCE POPS THROUGH THE PERIOD. TEMPERATURES
WILL BE COLD ENOUGH FOR SNOW AS THE PRECIPITATION TYPE.
ON SATURDAY THE BULK OF THE MOISTURE WILL MOVE OUT OF THE
AREA...REDUCING THE CHANCES FOR SNOW. CANNOT RULE OUT SOME FLURRIES
/OR PERHAPS FREEZING DRIZZLE IF ENOUGH MOISTURE EXITS ALOFT/. WILL
PUT SOME FLURRIES IN FOR NOW.
ARCTIC FRONT APPROACHES SATURDAY NIGHT AND MOVES THROUGH ON SUNDAY.
WENT WITH SOME SLIGHT CHANCE POPS FAR NORTHWEST LATE IN THE NIGHT TO
ACCOUNT FOR THE POTENTIAL OF THE FRONT REACHING THERE BY 12Z.
EXPECT TYPICAL CONDITIONS TO OCCUR ON SUNDAY WHEN AN ARCTIC FRONT
MOVES THROUGH...SO WENT SCATTERED SNOW SHOWERS ALL AREAS. NAM
INDICATES SNOW SQUALL POTENTIAL IN SOME AREAS...AND MODEL TIME
SECTIONS SHOW PERHAPS SOME WEAK INSTABILITY. THUS SOME OF THE SNOW
SHOWERS COULD BE BRIEFLY HEAVY. HOWEVER OVERALL ACCUMULATION LOOKS
TO BE LESS THAN AN INCH.
GENERALLY STAYED WITH A MODEL BLEND FOR TEMPERATURES THROUGH THE
SHORT TERM.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 255 AM EST FRI JAN 15 2016
A DRY AND BITTER COLD START WILL OCCUR DURING THE LONG TERM AS A COLD
UPPER LOW MOVES EAST ACROSS THE GREAT LAKES. MODELS INDICATE 850 MB
TEMPERATURES NEAR -20 CELSIUS AND SURFACE TEMPERATURES APPROACHING ZERO
ON MONDAY.
HIGH PRESSURE WILL MOVE EAST ACROSS OUR REGION TUESDAY. THE UPPER FLOW
WILL BECOME MORE ZONAL DURING THE 2ND HALF OF THE LONG TERM. HOWEVER A
COUPLE OF SYSTEMS IN THE SOUTHERN STREAM WILL BRING LOW CHANCES OF SNOW
LATE TUESDAY NIGHT INTO WEDNESDAY FOLLOWED BY ANOTHER SYSTEM BRINGING
CHANCE POPS AGAIN WEDNESDAY NIGHT AND THURSDAY. MODEL LOW LEVEL THICKNESS
INDICATE MIXED PRECIPITATION MAY OCCUR OVER SOUTHERN SECTIONS BY THURSDAY...
WHILE MOST OTHER AREAS REMAIN FROZEN.
MADE A FEW TWEAKS TO LOWER MIN TEMPERATURES SLIGHTLY TUESDAY MORNING AND RAISED
MINS SLIGHTLY WEDNESDAY MORNING AND THURSDAY. OTHERWISE...MODEL INITIALIZATION
TEMPERATURES SEEM REASONABLE.
&&
.AVIATION /DISCUSSION FOR THE 150600Z TAFS/...
ISSUED AT 1136 PM EST THU JAN 14 2016
STRENGTHENING LOW LEVEL SOUTH SOUTHWESTERLY FLOW TONIGHT SHOULD ALLOW FOR
CEILINGS 040-050 CURRENTLY OVER THE LOWER MISSISSIPPI VALLEY TO ADVECT
OVER THE TERMINALS BY 150900Z. THE SUSTAINED WARM/MOIST ADVECTION PATTERN
MAY ALLOW FOR CEILINGS TO FALL INTO THE MVFR CATEGORY TOWARDS/AFTER SUNRISE
ON FRIDAY...AND EVENTUALLY INTO THE IFR CATEGORY BY 151800Z.
ORGANIZED LIFT FROM APPROACHING SYSTEM WILL BEGIN MOVING INTO THE AREA
BY THE LATE MORNING HOURS ON FRIDAY...SO SHOULD SEE AREAS OF RAIN STARTING
TO IMPACT THE TERMINALS FROM THE SOUTHWEST AFTER THAT TIME.
SOME CONCERN FOR LOW LEVEL WIND SHEAR OVERNIGHT AROUND 015 AS A
40-45KT LOW LEVEL JET MOVES THROUGH. AT THIS TIME...IT APPEARS WIND SHEAR
WILL REMAIN JUST BELOW CRITERIA. THREAT FOR LOW LEVEL WIND SHEAR SHOULD
DIMINISH AFTER SUNRISE AS LOW LEVEL JET SHIFTS EAST AND WEAKENS.
SURFACE WINDS GENERALLY 180-200 DEGREES AT 10-13 KTS THROUGH MIDDAY FRIDAY.
MAY BE SOME LOCALIZED SURFACE GUSTS 20-25 KTS OVERNIGHT AS THE LOW LEVEL
JET MAY TEMPORARILY BREAK THE INVERSION.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...PUMA
SHORT TERM...50
LONG TERM...JH
AVIATION...JAS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1136 PM EST THU JAN 14 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 245 PM EST THU JAN 14 2016
A COLD FRONT WILL BRING RAIN TO CENTRAL INDIANA FRIDAY...THEN AN
ARCTIC COLD FRONT WILL BRING SOME SNOW ON SUNDAY ALONG WITH MUCH
COLDER AIR. THE FRIGID AIR WILL LAST UNTIL MID WEEK BEFORE
TEMPERATURES MODERATE SOME. SOME LIGHT SNOW IS POSSIBLE TUESDAY
NIGHT AND AGAIN THURSDAY.
&&
.NEAR TERM /OVERNIGHT|/...
ISSUED AT 933 PM EST THU JAN 14 2016
LOW PRESSURE CENTERED OVER IOWA WAS HELPING TO PROVIDE A WARM AND
SOUTHERLY FLOW OF AIR TO CENTRAL INDIANA AS DEW POINTS HAVE SOARED
INTO THE 30S AND TEMPS WERE HOLDING IN THE 40S. SATELLITE SHOWS
SOME MID AND HIGH CLOUD ACROSS TENNESSEE AND KENTUCKY STREAMING
NORTH TOWARD INDIANA.
GFS 290K SURFACE REVEALS GOOD ISENTROPIC LIFT EXPECTED BY 12Z AS A
SURGE OF MOISTURE ARRIVES WITH SPECIFIC HUMIDITIES OVER 5 G/KG.
TIME HEIGHTS AND FORECAST SOUNDINGS ALSO SHOWING GOOD LOWER LEVEL
SATURATION BY 12Z. HRRR SHOWS PRECIP BREAKING OUT TOWARD 12Z
WITHIN THE ISENTROPIC LIFT. BETTER FORCING WILL ARRIVE AFTER 12Z
AS THE SHORT WAVE OVER THE WESTERN PLAINS ARRIVES IN CENTRAL
INDIANA. THUS WILL CONTINUE THE ONGOING FORECAST OVERNIGHT...WITH
INCREASING CLOUDS AND MAINLY A DRY NIGHT...BUT INCHING POPS UPWARD
AFTER 09Z.
AS FOR TEMPS...HAVE RAISED TEMPS ABOUT 2-3 DEGREES DUE TO EXPECTED
INCREASING CLOUDS ALONG WITH ONGOING WARM AIR ADVECTION.
&&
.SHORT TERM.../FRIDAY THROUGH SUNDAY/
ISSUED AT 245 PM EST THU JAN 14 2016
FOCUS IS ON PRECIPITATION CHANCES EARLY AND LATE IN THE PERIOD.
OVERALL...MODELS ARE SIMILAR WITH THE BIG PICTURE. THERE ARE SOME
TIMING DIFFERENCES WITH THE ARCTIC FRONT SATURDAY NIGHT/SUNDAY
MORNING. THAT FAR OUT...DECIDED A BLEND WOULD STILL WORK OUT BEST
GIVEN THE UNCERTAINTY INVOLVED.
ON FRIDAY AN UPPER TROUGH AND COLD FRONT WILL MOVE INTO THE AREA.
850MB WINDS NEAR 50KT...ISENTROPIC LIFT...AND LARGER SCALE DYNAMICS
FROM THE TROUGH WILL WORK TOGETHER TO PRODUCE RAIN ACROSS THE AREA.
WENT LIKELY OR CATEGORICAL POPS ALL AREAS.
RAIN WILL DIMINISH ACROSS THE WEST DURING THE AFTERNOON BEHIND THE
FRONT...AND TEMPERATURES MAY COOL ENOUGH THERE FOR SOME SNOW TO MIX
IN WITH ANY LINGERING RAIN BY LATE FRIDAY AFTERNOON.
UPPER TROUGH AXIS WILL STILL BE CROSSING THE AREA FRIDAY EVENING AND
CYCLONIC FLOW WILL CONTINUE THROUGH THE NIGHT. THIS SHOULD BE ENOUGH
FOR MAINLY SOME SLIGHT CHANCE POPS THROUGH THE PERIOD. TEMPERATURES
WILL BE COLD ENOUGH FOR SNOW AS THE PRECIPITATION TYPE.
ON SATURDAY THE BULK OF THE MOISTURE WILL MOVE OUT OF THE
AREA...REDUCING THE CHANCES FOR SNOW. CANNOT RULE OUT SOME FLURRIES
/OR PERHAPS FREEZING DRIZZLE IF ENOUGH MOISTURE EXITS ALOFT/. WILL
PUT SOME FLURRIES IN FOR NOW.
ARCTIC FRONT APPROACHES SATURDAY NIGHT AND MOVES THROUGH ON SUNDAY.
WENT WITH SOME SLIGHT CHANCE POPS FAR NORTHWEST LATE IN THE NIGHT TO
ACCOUNT FOR THE POTENTIAL OF THE FRONT REACHING THERE BY 12Z.
EXPECT TYPICAL CONDITIONS TO OCCUR ON SUNDAY WHEN AN ARCTIC FRONT
MOVES THROUGH...SO WENT SCATTERED SNOW SHOWERS ALL AREAS. NAM
INDICATES SNOW SQUALL POTENTIAL IN SOME AREAS...AND MODEL TIME
SECTIONS SHOW PERHAPS SOME WEAK INSTABILITY. THUS SOME OF THE SNOW
SHOWERS COULD BE BRIEFLY HEAVY. HOWEVER OVERALL ACCUMULATION LOOKS
TO BE LESS THAN AN INCH.
GENERALLY STAYED WITH A MODEL BLEND FOR TEMPERATURES THROUGH THE
SHORT TERM.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 235 PM EST THU JAN 14 2016
VERY COLD START TO THE LONG TERM PERIOD EXPECTED...WITH LOWS IN THE
SINGLE DIGITS OR COLDER EARLY IN THE WEEK AND HIGHS ONLY IN THE LOW
TO MID TEENS MONDAY. TEMPERATURES SHOULD MODERATE THROUGH THE
REMAINDER OF THE WEEK WITH THE FREEZING MARK POTENTIALLY MAKING IT
BACK TO INDY BY THURSDAY.
REMOVED SOME SLIGHT CHANCE POPS IN PERIODS WHEN NEITHER THE GFS OR
EURO PRODUCED ANY QPF AND UPPER LEVEL SUPPORT WAS MINIMAL OR
NONEXISTENT. BLENDED INITIALIZATION TENDS TO OVERDO LOW POPS SO THIS
IS NOT SURPRISING.
MAY SEE A FEW FLAKES TUESDAY NIGHT AND PERHAPS THURSDAY AS ANOTHER
SYSTEM APPROACHES THE AREA. TEMPERATURES WILL BE MORE BORDERLINE
LATE IN THE WEEK AND SOME MIXED PRECIPITATION CANNOT BE RULED OUT.
&&
.AVIATION /DISCUSSION FOR THE 150600Z TAFS/...
ISSUED AT 1136 PM EST THU JAN 14 2016
STRENGTHENING LOW LEVEL SOUTH SOUTHWESTERLY FLOW TONIGHT SHOULD ALLOW FOR
CEILINGS 040-050 CURRENTLY OVER THE LOWER MISSISSIPPI VALLEY TO ADVECT
OVER THE TERMINALS BY 150900Z. THE SUSTAINED WARM/MOIST ADVECTION PATTERN
MAY ALLOW FOR CEILINGS TO FALL INTO THE MVFR CATEGORY TOWARDS/AFTER SUNRISE
ON FRIDAY...AND EVENTUALLY INTO THE IFR CATEGORY BY 151800Z.
ORGANIZED LIFT FROM APPROACHING SYSTEM WILL BEGIN MOVING INTO THE AREA
BY THE LATE MORNING HOURS ON FRIDAY...SO SHOULD SEE AREAS OF RAIN STARTING
TO IMPACT THE TERMINALS FROM THE SOUTHWEST AFTER THAT TIME.
SOME CONCERN FOR LOW LEVEL WIND SHEAR OVERNIGHT AROUND 015 AS A
40-45KT LOW LEVEL JET MOVES THROUGH. AT THIS TIME...IT APPEARS WIND SHEAR
WILL REMAIN JUST BELOW CRITERIA. THREAT FOR LOW LEVEL WIND SHEAR SHOULD
DIMINISH AFTER SUNRISE AS LOW LEVEL JET SHIFTS EAST AND WEAKENS.
SURFACE WINDS GENERALLY 180-200 DEGREES AT 10-13 KTS THROUGH MIDDAY FRIDAY.
MAY BE SOME LOCALIZED SURFACE GUSTS 20-25 KTS OVERNIGHT AS THE LOW LEVEL
JET MAY TEMPORARILY BREAK THE INVERSION.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...PUMA
SHORT TERM...50
LONG TERM...NIELD
AVIATION...JAS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1100 PM EST SAT JAN 16 2016
.UPDATE...
ISSUED AT 1052 PM EST SAT JAN 16 2016
THE LIGHT WINTRY PRECIP HAS GENERALLY BECOME MORE CELLULAR OR
SHOWERY OVER THE PAST FEW HOURS. CLOUD TOP TEMPS SUGGEST THAT THIS
IS EITHER FLURRIES OR LIGHT SNOW SHOWERS FOR THE MOST PART...BUT
SOME FREEZING DRIZZLE STILL CANNOT BE RULED OUT SINCE THE MOISTURE
IS SOMEWHAT SHALLOW.
THE 0Z NAM AND 0Z GFS RUNS HAVE LED TO SOME INCREASED CONFIDENCE
THAT THE VA BORDER COUNTIES...ESPECIALLY FROM HARLAN NORTHEAST TO
PIKE COUNTY COULD PICK UP A HALF OF AN INCH OR SO NEAR THE
VIRGINIA BORDER LATE TONIGHT INTO EARLY ON SUNDAY. THIS AREA
APPEARS DESTINED TO BE CLIPPED BY SOME PRECIP ON THE NW EDGE OF
LOW PRESSURE PASSING TO THE SOUTHEAST OF THE AREA.
OTHERWISE...NO SIGNIFICANT CHANGES WERE MADE AT THIS TIME.
UPDATE ISSUED AT 705 PM EST SAT JAN 16 2016
UPSLOPE FLOW IS CURRENTLY PRESENT ACROSS THE AREA WITH RATHER
SHALLOW MOISTURE REMAINING UP TO NEAR 850 MB. RADAR SHOWS SOME
GENERALLY WEAK RETURNS FALLING AS EITHER VERY LIGHT SNOW OR
FLURRIES OR SOME DRIZZLE OR FREEZING DRIZZLE WHERE TEMPERATURES
ARE BELOW FREEZING. SOME LIGHT FREEZING DRIZZLE OCCURRED AT JKL
SINCE LATE AFTERNOON...BUT ONLY VERY LIGHT FLURRIES ARE FALLING AT
PRESENT. NEAR HAZARD IN PERRY COUNTY...WE RECENTLY HAD A PUBLIC
REPORT OF LIGHT SNOW WITH A DUSTING HAVING OCCURRED THERE
RECENTLY.
OVERALL...THE GRIDS HAVE BEEN ADJUSTED TO THE RECENT TRENDS IN
OBSERVATIONS AND TO ALLOW FOR FLURRIES...DRIZZLE OR FREEZING
DRIZZLE A BIT LATER INTO THE NIGHT AS MODELS HAVE THE MOISTURE
BECOMING MORE SHALLOW IN THE LOW LEVELS OVERNIGHT. CONFIDENCE IN
THE TYPE ANY LIGHT PRECIPITATION WILL TAKE IS A BIT LOW AT THIS
TIME. EITHER WAY...WITH SOME LINGERING MOISTURE ON THE PAVEMENT
IN SOME AREAS SOME BLACK ICE CANNOT BE RULED OUT OVERNIGHT. THE
HWO WAS UPDATED ACCORDINGLY AND AN SPS WAS ALSO ISSUED.
THE SECOND CONCERN IS THE POTENTIAL FOR SOME LIGHT SNOW LATE
TONIGHT AND EARLY ON SUN NEAR THE VA BORDER ON THE FAR NW FRINGE
OF A SFC LOW PASSING WELL TO THE SOUTHEAST OF THE AREA. THE 18Z
NAM AND RECENT RAP GUIDANCE KEEP THIS SOUTHEAST OF THE AREA LATE
TONIGHT OR HOLD OFF UNTIL 12Z AND AFTER AND ARE LIGHTER THAN THE
18Z GFS GUIDANCE. THE MOST RECENT HRRR RUN WOULD LEND SOME SUPPORT
FOR THE 18Z GFS GUIDANCE. WE HAVE OPTED TO INCREASE POPS TO THE
CHANCE RANGE LATE TONIGHT AND ALONG THE VA BORDER ACCORDINGLY
ALTHOUGH TRENDS WILL HAVE TO BE MONITORED FOR A POSSIBLE FURTHER
INCREASE IN POPS DURING THAT PERIOD.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 301 PM EST SAT JAN 16 2016
CURRENT CONDITIONS ACROSS THE REGION FEATURE AN AREA OF LOW LEVEL
MOISTURE OVER THE OH VALLEY REGION WITH SOME WEAK UPSLOPE
RESULTING IN A FEW AREAS OF DRIZZLE OR EVEN SNOW GRAINS. AS OF
1930Z...THE BULK OF THE LOW LEVEL MOISTURE HAS LIFTED OFF TO THE
EAST BUT SOME PATCHY DRIZZLE MAY LINGER INTO THIS EVENING. CLOUD
COVER WILL LINGER OVER THE AREA THROUGH THE OVERNIGHT PERIOD AND
INTO SUNDAY.
BY SUNDAY...A STRONG JET DIVES SOUTHEAST INTO THE GULF REGION AS A
STRONG SHORTWAVE DEVELOPS OVER THE NORTHERN GULF. THIS FEATURE
TRACK NORTHEAST ALONG THE COAST. SURFACE LOW DEVELOPMENT WRAPS
MOISTURE AROUND TO THE NORTH AND INTO THE APPALACHIAN MOUNTAINS.
FORTUNATELY...MODELS CONTINUE TO DISPLACE MOST OF THE LIFT AND
MOISTURE TO THE SOUTH AND EAST OF EASTERN KENTUCKY. THE TROUGH
DOES NUDGE NORTH ENOUGH TO BRING SOME MOISTURE INTO SOUTHEASTERN
KENTUCKY AND THUS WILL RESULT IN SOME SNOWFALL ACROSS THE AREA FOR
SUNDAY. AT THIS POINT...MODELS ARE BRINGING A FEW HUNDREDTHS INTO
THE SOUTHEAST BUT A FEW EARLIER RUNS OF THE GFS HAD UP TO THE
TENTH WHICH WOULD MEAN A BIT MORE SNOW BUT AT THIS POINT...THAT
RUN IS AN OUTLIER SO WILL GO WITH THE MORE CONSERVATIVE HI RES
SOLUTIONS. A DUSTING TO A FEW TENTHS CAN BE EXPECTED LATE TONIGHT
INTO SUNDAY.
ON THE HEALS OF THIS FEATURE WILL BE A RELATIVELY DRY ARCTIC
FRONT WITH SOME OF THE COLDEST AIR OF THE YEAR. MINUS 20 CELSIUS
850 TEMPS ARE POISED TO ENTER THE BLUEGRASS REGION SUNDAY EVENING
INTO SUNDAY NIGHT. IN FACT...AFTER 18Z SUNDAY...TEMPS WILL PLUMMET
THROUGH THE EVENING AND SUNDAY NIGHT INTO THE TEENS AND EVEN
SINGLE DIGITS IN THE BLUEGRASS COUNTIES BY MONDAY MORNING. THE
APPROACHING ARCTIC FRONT WILL BE ENOUGH TO KEEP A FEW FLURRIES
ACROSS THE AREA INTO SUNDAY NIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 PM EST SAT JAN 16 2016
...COLDEST AIR OF THE SEASON ARRIVES MONDAY...
THE MODELS ARE IN QUITE GOOD AGREEMENT ALOFT AT THE START OF THE
EXTENDED PORTION OF THE FORECAST. THEY ALL DEPICT THE DEEP TROUGH
ROLLING EAST THROUGH ONTARIO ALLOWING THE LOW HEIGHTS TO REBOUND
OVER KENTUCKY. HOWEVER...THE FLOW WILL REMAIN OUT OF THE NORTHWEST
WITH ENERGY STILL TRACKING OVER THE AREA INTO TUESDAY. THE MODELS
START TO EXHIBIT SPREAD BY MIDWEEK AS THEY DISAGREE ON THE AMOUNT OF
MINOR RIDGING THAT WILL PUSH NORTH INTO KENTUCKY FROM AN
INCREASINGLY ACTIVE SOUTHERN STREAM. FOR WEDNESDAY THE GFS IS MOST
AGGRESSIVE WITH A TROUGH IT SWINGS INTO THE MID MISSISSIPPI VALLEY
WHILE THE CANADIAN AND ECMWF ARE FLATTER WITH THIS FEATURE.
AGREEMENT IS SLIGHTLY BETTER FOR THE TRAILING RIDGE PASSING OVER THE
STATE INTO THURSDAY AHEAD OF A DEEPENING TROUGH OVER WESTERN TEXAS.
AGAIN THE GFS IS THE STRONGER MODEL WITH THIS CLOSING IT OFF AS A
LOW OVER NORTHERN ARKANSAS EARLY FRIDAY WHILE THE CANADIAN MODEL
SERVES AS A COMPROMISE SCENARIO BETWEEN THE OTHERS. HOWEVER...BY
MIDDAY FRIDAY...THE ECMWF ALSO FORMS A CLOSED LOW OVER THE DEEP
SOUTH...BUT STILL SIGNIFICANTLY WEAKER THAN THE GFS. BOTH THE GFS
AND ECMWF RUN THIS TROUGH TO THE EAST COAST BY SATURDAY MORNING...
THOUGH THE LATTER IS SUBSTANTIALLY FURTHER SOUTH AND STILL WEAKER.
THEY REMAIN PROGRESSIVE AS WELL INTO THE WEEKEND SWEEPING THE SYSTEM
OFF SHORE ON SATURDAY...AS HEIGHTS REBOUND LOCALLY. GIVEN THE
TROUBLES THE MODELS ARE HAVING FROM MID WEEK ON...WILL FAVOR A
BLENDED SOLUTION WITH A SLIGHT LEAN TOWARD A MORE DYNAMIC VERSION
MIDWAY BETWEEN THE GFS AND ECMWF TRACKS.
SENSIBLE WEATHER WILL FEATURE SOME OF THE COLDEST AIR OF THE SEASON
FLOODING SOUTHEAST INTO KENTUCKY BY MONDAY MORNING WITH A COUPLE
COLD DAYS AND NIGHTS ON TAP. DO EXPECT THE COLDEST PERIOD TO BE
MONDAY NIGHT AS THE ARCTIC HIGH SETTLES OVERHEAD RESULTING IN MOSTLY
CLEAR SKIES. THE COLD AIR WILL MODERATE INTO THE LATTER PART OF THE
WEEK JUST AS THE NEXT ILL-DEFINED SFC WEATHER SYSTEM PASSES THROUGH
WITH A CHANCE OF RAIN OR SNOW. STILL CANNOT RULE OUT A LOSS OF ICE
ON THE BACKSIDE OF THIS FIRST WEAK SYSTEM LEADING TO A CONCERN FOR
FREEZING DRIZZLE EARLY THURSDAY - WILL CONTINUE TO HIGHLIGHT THIS IN
THE HWO. THE MORE INTERESTING SYSTEM WILL TAKE SHAPE EARLY FRIDAY TO
THE SOUTH AND SHOULD BRUSH THROUGH KENTUCKY WITH A CHANCE OF SNOW OR
RAIN INTO THE WEEKEND. IF IT GETS STRONGER THAN IS CURRENTLY PROGGED
THIS COULD BE A MORE SIGNIFICANT STORM WITH THE RIGHT TRACK TO BE
IMPACTFUL. WE WILL HAVE TO WATCH THIS ONE CLOSELY AS IT EVOLVES IN
THE MODELS THROUGH THE START OF THE NEW WEEK.
ADJUSTED THE GRIDS FROM THE CR INIT MAINLY TO ACCOUNT FOR DECENT
SMALL RIDGE TO VALLEY TEMPERATURE DIFFERENCES FOR MONDAY AND TUESDAY
NIGHT. ALSO TWEAKED THE POP GRIDS LATER IN THE PERIOD TO REFLECT A
FORECAST CLOSER TO THE LATEST ECMWF.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 725 PM EST SAT JAN 16 2016
WEAK UPSLOPE WILL GIVE WAY TO A COLD FRONT DROPPING INTO THE
REGION ON SUNDAY. THIS COMBINATION SHOULD GENERALLY KEEP LOW CIGS
MAINLY IN THE MVFR RANGE...WITH IFR AT TIMES THROUGHOUT THE
PERIOD. WINDS SHOULD BE 10KT OR LESS. SOME PATCHY VERY LIGHT
SNOW...DRIZZLE OR FLURRIES WILL ALSO CREATE SOME INTERMITTENT
REDUCTION IN VISIBILITY TO MVFR OR LOWER.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...SHALLENBERGER
LONG TERM...GREIF
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
730 PM EST SAT JAN 16 2016
.UPDATE...
ISSUED AT 705 PM EST SAT JAN 16 2016
UPSLOPE FLOW IS CURRENTLY PRESENT ACROSS THE AREA WITH RATHER
SHALLOW MOISTURE REMAINING UP TO NEAR 850 MB. RADAR SHOWS SOME
GENERALLY WEAK RETURNS FALLING AS EITHER VERY LIGHT SNOW OR
FLURRIES OR SOME DRIZZLE OR FREEZING DRIZZLE WHERE TEMPERATURES
ARE BELOW FREEZING. SOME LIGHT FREEZING DRIZZLE OCCURRED AT JKL
SINCE LATE AFTERNOON...BUT ONLY VERY LIGHT FLURRIES ARE FALLING AT
PRESENT. NEAR HAZARD IN PERRY COUNTY...WE RECENTLY HAD A PUBLIC
REPORT OF LIGHT SNOW WITH A DUSTING HAVING OCCURRED THERE
RECENTLY.
OVERALL...THE GRIDS HAVE BEEN ADJUSTED TO THE RECENT TRENDS IN
OBSERVATIONS AND TO ALLOW FOR FLURRIES...DRIZZLE OR FREEZING
DRIZZLE A BIT LATER INTO THE NIGHT AS MODELS HAVE THE MOISTURE
BECOMING MORE SHALLOW IN THE LOW LEVELS OVERNIGHT. CONFIDENCE IN
THE TYPE ANY LIGHT PRECIPITATION WILL TAKE IS A BIT LOW AT THIS
TIME. EITHER WAY...WITH SOME LINGERING MOISTURE ON THE PAVEMENT
IN SOME AREAS SOME BLACK ICE CANNOT BE RULED OUT OVERNIGHT. THE
HWO WAS UPDATED ACCORDINGLY AND AN SPS WAS ALSO ISSUED.
THE SECOND CONCERN IS THE POTENTIAL FOR SOME LIGHT SNOW LATE
TONIGHT AND EARLY ON SUN NEAR THE VA BORDER ON THE FAR NW FRINGEOF
A SFC LOW PASSING WELL TO THE SOUTHEAST OF THE AREA. THE 18Z NAM
AND RECENT RAP GUIDANCE KEEP THIS SOUTHEAST OF THE AREA LATE
TONIGHT OR HOLD OFF UNTIL 12Z AND AFTER AND ARE LIGHTER THAN THE
18Z GFS GUIDANCE. THE MOST RECENT HRRR RUN WOULD LEND SOME SUPPORT
FOR THE 18Z GFS GUIDANCE. WE HAVE OPTED TO INCREASE POPS TO THE
CHANCE RANGE LATE TONIGHT AND ALONG THE VA BORDER ACCORDINGLY
ALTHOUGH TRENDS WILL HAVE TO BE MONITORED FOR A POSSIBLE FURTHER
INCREASE IN POPS DURING THAT PERIOD.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 301 PM EST SAT JAN 16 2016
CURRENT CONDITIONS ACROSS THE REGION FEATURE AN AREA OF LOW LEVEL
MOISTURE OVER THE OH VALLEY REGION WITH SOME WEAK UPSLOPE
RESULTING IN A FEW AREAS OF DRIZZLE OR EVEN SNOW GRAINS. AS OF
1930Z...THE BULK OF THE LOW LEVEL MOISTURE HAS LIFTED OFF TO THE
EAST BUT SOME PATCHY DRIZZLE MAY LINGER INTO THIS EVENING. CLOUD
COVER WILL LINGER OVER THE AREA THROUGH THE OVERNIGHT PERIOD AND
INTO SUNDAY.
BY SUNDAY...A STRONG JET DIVES SOUTHEAST INTO THE GULF REGION AS A
STRONG SHORTWAVE DEVELOPS OVER THE NORTHERN GULF. THIS FEATURE
TRACK NORTHEAST ALONG THE COAST. SURFACE LOW DEVELOPMENT WRAPS
MOISTURE AROUND TO THE NORTH AND INTO THE APPALACHIAN MOUNTAINS.
FORTUNATELY...MODELS CONTINUE TO DISPLACE MOST OF THE LIFT AND
MOISTURE TO THE SOUTH AND EAST OF EASTERN KENTUCKY. THE TROUGH
DOES NUDGE NORTH ENOUGH TO BRING SOME MOISTURE INTO SOUTHEASTERN
KENTUCKY AND THUS WILL RESULT IN SOME SNOWFALL ACROSS THE AREA FOR
SUNDAY. AT THIS POINT...MODELS ARE BRINGING A FEW HUNDREDTHS INTO
THE SOUTHEAST BUT A FEW EARLIER RUNS OF THE GFS HAD UP TO THE
TENTH WHICH WOULD MEAN A BIT MORE SNOW BUT AT THIS POINT...THAT
RUN IS AN OUTLIER SO WILL GO WITH THE MORE CONSERVATIVE HI RES
SOLUTIONS. A DUSTING TO A FEW TENTHS CAN BE EXPECTED LATE TONIGHT
INTO SUNDAY.
ON THE HEALS OF THIS FEATURE WILL BE A RELATIVELY DRY ARCTIC
FRONT WITH SOME OF THE COLDEST AIR OF THE YEAR. MINUS 20 CELSIUS
850 TEMPS ARE POISED TO ENTER THE BLUEGRASS REGION SUNDAY EVENING
INTO SUNDAY NIGHT. IN FACT...AFTER 18Z SUNDAY...TEMPS WILL PLUMMET
THROUGH THE EVENING AND SUNDAY NIGHT INTO THE TEENS AND EVEN
SINGLE DIGITS IN THE BLUEGRASS COUNTIES BY MONDAY MORNING. THE
APPROACHING ARCTIC FRONT WILL BE ENOUGH TO KEEP A FEW FLURRIES
ACROSS THE AREA INTO SUNDAY NIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 PM EST SAT JAN 16 2016
...COLDEST AIR OF THE SEASON ARRIVES MONDAY...
THE MODELS ARE IN QUITE GOOD AGREEMENT ALOFT AT THE START OF THE
EXTENDED PORTION OF THE FORECAST. THEY ALL DEPICT THE DEEP TROUGH
ROLLING EAST THROUGH ONTARIO ALLOWING THE LOW HEIGHTS TO REBOUND
OVER KENTUCKY. HOWEVER...THE FLOW WILL REMAIN OUT OF THE NORTHWEST
WITH ENERGY STILL TRACKING OVER THE AREA INTO TUESDAY. THE MODELS
START TO EXHIBIT SPREAD BY MIDWEEK AS THEY DISAGREE ON THE AMOUNT OF
MINOR RIDGING THAT WILL PUSH NORTH INTO KENTUCKY FROM AN
INCREASINGLY ACTIVE SOUTHERN STREAM. FOR WEDNESDAY THE GFS IS MOST
AGGRESSIVE WITH A TROUGH IT SWINGS INTO THE MID MISSISSIPPI VALLEY
WHILE THE CANADIAN AND ECMWF ARE FLATTER WITH THIS FEATURE.
AGREEMENT IS SLIGHTLY BETTER FOR THE TRAILING RIDGE PASSING OVER THE
STATE INTO THURSDAY AHEAD OF A DEEPENING TROUGH OVER WESTERN TEXAS.
AGAIN THE GFS IS THE STRONGER MODEL WITH THIS CLOSING IT OFF AS A
LOW OVER NORTHERN ARKANSAS EARLY FRIDAY WHILE THE CANADIAN MODEL
SERVES AS A COMPROMISE SCENARIO BETWEEN THE OTHERS. HOWEVER...BY
MIDDAY FRIDAY...THE ECMWF ALSO FORMS A CLOSED LOW OVER THE DEEP
SOUTH...BUT STILL SIGNIFICANTLY WEAKER THAN THE GFS. BOTH THE GFS
AND ECMWF RUN THIS TROUGH TO THE EAST COAST BY SATURDAY MORNING...
THOUGH THE LATTER IS SUBSTANTIALLY FURTHER SOUTH AND STILL WEAKER.
THEY REMAIN PROGRESSIVE AS WELL INTO THE WEEKEND SWEEPING THE SYSTEM
OFF SHORE ON SATURDAY...AS HEIGHTS REBOUND LOCALLY. GIVEN THE
TROUBLES THE MODELS ARE HAVING FROM MID WEEK ON...WILL FAVOR A
BLENDED SOLUTION WITH A SLIGHT LEAN TOWARD A MORE DYNAMIC VERSION
MIDWAY BETWEEN THE GFS AND ECMWF TRACKS.
SENSIBLE WEATHER WILL FEATURE SOME OF THE COLDEST AIR OF THE SEASON
FLOODING SOUTHEAST INTO KENTUCKY BY MONDAY MORNING WITH A COUPLE
COLD DAYS AND NIGHTS ON TAP. DO EXPECT THE COLDEST PERIOD TO BE
MONDAY NIGHT AS THE ARCTIC HIGH SETTLES OVERHEAD RESULTING IN MOSTLY
CLEAR SKIES. THE COLD AIR WILL MODERATE INTO THE LATTER PART OF THE
WEEK JUST AS THE NEXT ILL-DEFINED SFC WEATHER SYSTEM PASSES THROUGH
WITH A CHANCE OF RAIN OR SNOW. STILL CANNOT RULE OUT A LOSS OF ICE
ON THE BACKSIDE OF THIS FIRST WEAK SYSTEM LEADING TO A CONCERN FOR
FREEZING DRIZZLE EARLY THURSDAY - WILL CONTINUE TO HIGHLIGHT THIS IN
THE HWO. THE MORE INTERESTING SYSTEM WILL TAKE SHAPE EARLY FRIDAY TO
THE SOUTH AND SHOULD BRUSH THROUGH KENTUCKY WITH A CHANCE OF SNOW OR
RAIN INTO THE WEEKEND. IF IT GETS STRONGER THAN IS CURRENTLY PROGGED
THIS COULD BE A MORE SIGNIFICANT STORM WITH THE RIGHT TRACK TO BE
IMPACTFUL. WE WILL HAVE TO WATCH THIS ONE CLOSELY AS IT EVOLVES IN
THE MODELS THROUGH THE START OF THE NEW WEEK.
ADJUSTED THE GRIDS FROM THE CR INIT MAINLY TO ACCOUNT FOR DECENT
SMALL RIDGE TO VALLEY TEMPERATURE DIFFERENCES FOR MONDAY AND TUESDAY
NIGHT. ALSO TWEAKED THE POP GRIDS LATER IN THE PERIOD TO REFLECT A
FORECAST CLOSER TO THE LATEST ECMWF.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 725 PM EST SAT JAN 16 2016
WEAK UPSLOPE WILL GIVE WAY TO A COLD FRONT DROPPING INTO THE
REGION ON SUNDAY. THIS COMBINATION SHOULD GENERALLY KEEP LOW CIGS
MAINLY IN THE MVFR RANGE...WITH IFR AT TIMES THROUGHOUT THE
PERIOD. WINDS SHOULD BE 10KT OR LESS. SOME PATCHY VERY LIGHT
SNOW...DRIZZLE OR FLURRIES WILL ALSO CREATE SOME INTERMITTENT
REDUCTION IN VISIBILITY TO MVFR OR LOWER.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...SHALLENBERGER
LONG TERM...GREIF
AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
351 PM EST FRI JAN 15 2016
.UPDATE...
ISSUED AT 132 PM EST FRI JAN 15 2016
RAIN FROM SE SYSTEM HAS PROGRESS AS FAR NW AS KJKL...AND HAVE
UPDATED WITH HIGHER AFTERNOON POPS OVER THE SE PART OF THE AREA.
UPDATE ISSUED AT 1157 AM EST FRI JAN 15 2016
SYSTEM MOVING THROUGH THE SE CONUS WILL END UP HAVING A GREATER
INFLUENCE ON OUR LOCAL AREA THAN EARLIER FORECAST. RAIN IS
SPREADING INTO OUR FAR SOUTHEAST COUNTIES...AND POPS HAVE BEEN
RAISED THERE FOR TODAY. WET BULB TEMPERATURES OVER THE HIGH
ELEVATIONS NEAR THE VA BORDER ARE BELOW FREEZING...AND THIS COULD
ALLOW FOR SOME SNOW TO INITIALLY OCCUR AS PRECIP MOVES IN...BUT IT
SHOULD FADE AWAY AS WET BULB READINGS EVENTUALLY RISE.
MEANWHILE... PRECIP OVER CENTRAL KY AHEAD OF A COLD FRONT HAS BEEN
SLOWER TO MAKE ITS WAY EAST THAN WAS EXPECTED...AND HAVE LOWERED
POPS TODAY AND HELD PRECIP OFF LONGER IN THE NW PART OF THE AREA.
WHAT IS LEFT OF THE FRONTAL PRECIP WILL MAKE ITS WAY ACROSS THE
REMAINDER OF OUR AREA...ESPECIALLY THE NORTH...THIS EVENING.
BEHIND THE COLD FRONT...POTENTIAL FOR PRECIP AND ITS TYPE REMAIN
ISSUES. MOISTURE WILL BE SHALLOW AND MAY NOT REACH -10C FOR ICE
FORMATION. HOWEVER...SURFACE TEMPS SHOULD EVENTUALLY REACH
FREEZING FOR SOME LOCATIONS. PRECIP TYPE COULD END UP BEING
DRIZZLE...FREEZING DRIZZLE...FLURRIES...OR SOME COMBINATION. AT
THIS POINT...HAVE ONLY USED SLIGHT CHANCE WORDING FOR THE
NONMEASURABLE PRECIP FROM LATE TONIGHT INTO SATURDAY NIGHT.
UPDATE ISSUED AT 751 AM EST FRI JAN 15 2016
FRESHENED UP THE HOURLY TEMPERATURES AND DEW POINTS. SHELTERED
VALLEYS ARE RANGING FROM THE MID 20S TO THE LOWER 30S...WITH MOST
OTHER LOCATIONS REPORTING IN THE LOW TO MID 40S. THICKER CLOUDS
ARE STARTING TO OVERTAKE THE AREA...WITH RAIN SHOWERS MOVING IN
ACROSS PORTIONS OF WESTERN KENTUCKY. THE LATEST HRRR GUIDANCE
CONTINUES TO SHOW LITTLE IN THE WAY OF SHOWER ACTIVITY UNTIL THIS
AFTERNOON...WHEN THE FAR SOUTHEAST MAY GET BRUSHED. WILL LET THE
CURRENT FORECAST RIDE FOR NOW. GRID UPDATES WILL BE FORTHCOMING.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 344 AM EST FRI JAN 15 2016
SURFACE LOW PRESSURE IS CURRENTLY CRUISING TOWARDS THE GREAT
LAKES...WITH AN ATTENDANT COLD FRONT ALIGNED SOUTHWEST THROUGH THE
SOUTHERN PLAINS. ANOTHER LOW PRESSURE SYSTEM IS ORGANIZING ACROSS
THE NORTH CENTRAL GULF OF MEXICO...WITH HIGH PRESSURE RETREATING
OFF THE CAROLINA COAST. ALOFT...A SHORT WAVE TROUGH IS MOVING
ACROSS THE PLAINS WITHIN THE NORTHERN STREAM...WHILE ANOTHER ONE
IS MOVING THROUGH THE NORTH CENTRAL GULF WITHIN THE SOUTHERN
STREAM. THIS IS ALLOWING FOR DEEPER SOUTHWEST FLOW ACROSS THE MID
AND LOWER MISSISSIPPI VALLEY...WITH PLENTY OF HIGH CLOUDS
STREAMING IN FROM THE SOUTHWEST. EASTERN KENTUCKY REMAINS UNDER
PARTLY CLOUDY TO MOSTLY CLEAR SKIES...WITH TEMPERATURES VARYING
FROM THE MID TO UPPER 40S IN THE BROADER VALLEYS AND
RIDGETOPS...WHILE SHELTERED VALLEYS IN THE EAST REMAIN SOME 20
DEGREES COLDER...IN THE MID TO UPPER 20S.
THE TWO AFOREMENTIONED SYSTEMS WILL TRACK EAST TODAY...WITH
EASTERN KENTUCKY REMAINING SPLIT BETWEEN THEM. THE MODELS HAVE
TRENDED A BIT DRIER WITH THE SOUTHERN STREAM MOISTURE...KEEPING
MOST OF THIS JUST TO OUR SOUTHEAST. MOST OF THE FORCING WILL COME
FROM THE NORTHERN STREAM SYSTEM AS THE TROUGH AXIS AND SURFACE
COLD FRONT APPROACH FROM THE WEST. LIGHT RAIN SHOWERS WILL MOVE IN
FROM THE WEST TODAY...WITH THE MAJORITY OF THE ACTIVITY HOLDING
OFF UNTIL THIS AFTERNOON. THE BEST OVERALL RAIN CHANCES STILL LOOK
TO OCCUR IN THE FAR WEST...WITH LESSER CHANCES IN OUR NORTHEAST
COUNTIES. HIGHS TODAY WILL RECOVER INTO THE LOW TO MID 50S...WITH
SOME SPOTS REACHING THE UPPER 50S IN THE EAST...WHERE THICKER
CLOUD COVER WILL HOLD OFF THE LONGEST.
THE COLD FRONT AND TROUGH AXIS WILL SWING THROUGH THE AREA BETWEEN
00 AND 06Z TONIGHT...WITH A GOOD CHANCE OF LIGHT PRECIPITATION
CONTINUING. COLD ADVECTION WILL BE UNDERWAY OVERNIGHT...WITH LOWS
FOR MOST COOLING OFF TO THE LOW TO MID 30S. THE ONLY EXCEPTION
WILL BE THE HIGHER TERRAIN...WHERE LOWS WILL SETTLE INTO THE 20S.
HAVE LEFT A MENTION OF SNOW IN THE FORECAST TOWARDS DAWN SATURDAY
MORNING...HOWEVER WITH ICE IN QUESTION...DRIZZLE AND OR FREEZING
DRIZZLE MAY BECOME A CONCERN FOR THE HIGHER ELEVATIONS.
ANY LIGHT PRECIPITATION LINGERING INTO SATURDAY WILL TAPER OFF
DURING THE DAY AS FORCING DIMINISHES. HIGH TEMPERATURES WILL NOT
RECOVER MUCH DURING THE DAY WITH THICK CLOUD COVER LOCKED INTO
PLACE THANKS TO A POST-FRONTAL INVERSION. HAVE UNDERCUT THE
BLENDED GUIDANCE FOR THE HIGHS...ONLY ALLOWING FOR A FEW DEGREE
OR SO RISE FROM SATURDAY MORNING LOWS.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 351 PM EST FRI JAN 15 2016
...COLDEST AIR OF SEASON LIKELY SUNDAY NIGHT THROUGH MONDAY NIGHT...
THE EXTENDED FORECAST PERIOD BEGINS ON SUNDAY NIGHT WITH A CONTINUED
ACTIVE AND AMPLIFIED PATTERN IN PLACE. STRONG RIDGING IS IN PLACE
OVER THE WESTERN CONUS WITH A DEEP AND BROAD LONGWAVE TROUGH OVER
THE EASTERN CONUS. A CLOSED LOW WILL THEN REMAIN IN PLACE OVER THE
GREAT LAKES REGION THROUGH MUCH OF THE EXTENDED BEFORE SHIFTING OFF
TO THE EAST AND INTO THE NEW ENGLAND REGION BY TUESDAY.
MEANWHILE...A COUPLE OF SHORTWAVES WILL ROTATE AROUND THE LOW AND
DIVE SOUTHEAST INTO THE OH VALLEY WITH THE FIRST TROUGH PASSING
THROUGH ON SUNDAY AND THE SECOND FEATURE PASSING THROUGH MONDAY
AFTERNOON INTO MONDAY NIGHT. THE SUNDAY SHORTWAVE DEVELOPS UNDER
SOME INTERACTION BETWEEN THE PFJ AND STJ OVER THE SOUTHEASTERN
CONUS. HOWEVER...THIS SET UP OCCURS A BIT FURTHER TO THE SOUTHEAST
KEEPING ANY SIGNIFICANT SNOWFALL TO THE SOUTH AND EAST.
THE SECOND WAVE THAT TRACKS SOUTHEAST THROUGH THE OH VALLEY WILL BE
A RELATIVELY DRY ARCTIC FRONT AS THE COLDEST AIR OF THE SEASON
FILTERS INTO THE AREA. IN FACT AS SKIES CLEAR OUT MONDAY NIGHT AND
WINDS DECREASE...SOME OF THE DEEPER VALLEYS MAY DROP TO NEAR OR EVEN
POSSIBLY BELOW ZERO ON TUESDAY MORNING. WIND CHILLS WILL LIKELY
BE IN THE 0 TO -10 RANGE.
BY WEDNESDAY...THE UPPER LEVEL PATTERN BECOMES LESS
AMPLIFIED...NEARLY ZONAL ACROSS THE EASTERN CONUS BUT MAINTAINING A
RIDGE OVER THE WEST. A SHORTWAVE WILL TRACK ACROSS THE FRONT RANGE
AND INTO THE CENTRAL MS VALLEY AND THROUGH EASTERN KENTUCKY BY
THURSDAY MORNING. AT THIS TIME...ENOUGH OF THE COLDER AIR MAY STILL
BE IN PLACE FOR THIS PRECIP TO BEGIN AS SNOW. IN FACT...THIS COULD
BE THE FIRST INCH OF SNOWFALL FOR MANY PLACES...IF TRENDS KEEP THE
COLDER AIR IN PLACE. THE SUPER BLEND KEEP AT LEAST CHANCE POPS OVER
THE AREA FOR THE WEDNESDAY THROUGH THURSDAY PERIOD AS SOME UPSLOPE
IS POSSIBLE BEHIND THIS FRONT. MODELS AS WELL...HAVE TRENDED ENOUGH
MOISTURE ASSOCIATED WITH THIS FEATURE TO KEEP SNOW IN THE FORECAST.
WILL NEED TO MONITOR FOR ANY CHANGES IN THE TRENDS CONCERNING THIS
FEATURE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 110 PM EST FRI JAN 15 2016
RAIN WILL MOVE THROUGH THE FAR SOUTHEAST PART OF THE FORECAST AREA
THIS AFTERNOON...WITH THE STEADY RAIN THEN EXITING INTO WV BY
AROUND 23Z. MEANWHILE... ANOTHER AREA OF RAIN ASSOCIATED WITH A
COLD FRONT OVER CENTRAL KY AT MID DAY WILL MOVE EAST. THIS WILL
MOVE THROUGH THE JKL FORECAST AREA FROM ABOUT 22Z-03Z...
DISSIPATING AT THE SAME TIME. ONCE THE COLD FRONT MOVES THROUGH
THIS EVENING...DRIZZLE WILL BE POSSIBLE AT TIMES THROUGH THE
REMAINDER OF THE PERIOD...AND SOME FLURRIES OR EVEN FREEZING
DRIZZLE CAN NOT BE RULED OUT AS TEMPERATURES FALL TO NEAR FREEZING
AROUND DAWN.
CONDITIONS SHOULD LARGELY BE VFR UNTIL EARLY THIS EVENING...WITH
THE EXCEPTION OF SOME MVFR NEAR THE VA BORDER. AS THE COLD FRONT
MOVES THROUGH THIS EVENING...CONDITIONS ARE EXPECTED TO
DETERIORATE TO IFR AND REMAIN THERE THROUGH MOST OF THE REMAINDER
OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GEOGERIAN
LONG TERM...SHALLENBERGER
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
132 PM EST FRI JAN 15 2016
.UPDATE...
ISSUED AT 132 PM EST FRI JAN 15 2016
RAIN FROM SE SYSTEM HAS PROGRESS AS FAR NW AS KJKL...AND HAVE
UPDATED WITH HIGHER AFTERNOON POPS OVER THE SE PART OF THE AREA.
UPDATE ISSUED AT 1157 AM EST FRI JAN 15 2016
SYSTEM MOVING THROUGH THE SE CONUS WILL END UP HAVING A GREATER
INFLUENCE ON OUR LOCAL AREA THAN EARLIER FORECAST. RAIN IS
SPREADING INTO OUR FAR SOUTHEAST COUNTIES...AND POPS HAVE BEEN
RAISED THERE FOR TODAY. WET BULB TEMPERATURES OVER THE HIGH
ELEVATIONS NEAR THE VA BORDER ARE BELOW FREEZING...AND THIS COULD
ALLOW FOR SOME SNOW TO INITIALLY OCCUR AS PRECIP MOVES IN...BUT IT
SHOULD FADE AWAY AS WET BULB READINGS EVENTUALLY RISE.
MEANWHILE... PRECIP OVER CENTRAL KY AHEAD OF A COLD FRONT HAS BEEN
SLOWER TO MAKE ITS WAY EAST THAN WAS EXPECTED...AND HAVE LOWERED
POPS TODAY AND HELD PRECIP OFF LONGER IN THE NW PART OF THE AREA.
WHAT IS LEFT OF THE FRONTAL PRECIP WILL MAKE ITS WAY ACROSS THE
REMAINDER OF OUR AREA...ESPECIALLY THE NORTH...THIS EVENING.
BEHIND THE COLD FRONT...POTENTIAL FOR PRECIP AND ITS TYPE REMAIN
ISSUES. MOISTURE WILL BE SHALLOW AND MAY NOT REACH -10C FOR ICE
FORMATION. HOWEVER...SURFACE TEMPS SHOULD EVENTUALLY REACH
FREEZING FOR SOME LOCATIONS. PRECIP TYPE COULD END UP BEING
DRIZZLE...FREEZING DRIZZLE...FLURRIES...OR SOME COMBINATION. AT
THIS POINT...HAVE ONLY USED SLIGHT CHANCE WORDING FOR THE
NONMEASURABLE PRECIP FROM LATE TONIGHT INTO SATURDAY NIGHT.
UPDATE ISSUED AT 751 AM EST FRI JAN 15 2016
FRESHENED UP THE HOURLY TEMPERATURES AND DEW POINTS. SHELTERED
VALLEYS ARE RANGING FROM THE MID 20S TO THE LOWER 30S...WITH MOST
OTHER LOCATIONS REPORTING IN THE LOW TO MID 40S. THICKER CLOUDS
ARE STARTING TO OVERTAKE THE AREA...WITH RAIN SHOWERS MOVING IN
ACROSS PORTIONS OF WESTERN KENTUCKY. THE LATEST HRRR GUIDANCE
CONTINUES TO SHOW LITTLE IN THE WAY OF SHOWER ACTIVITY UNTIL THIS
AFTERNOON...WHEN THE FAR SOUTHEAST MAY GET BRUSHED. WILL LET THE
CURRENT FORECAST RIDE FOR NOW. GRID UPDATES WILL BE FORTHCOMING.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 344 AM EST FRI JAN 15 2016
SURFACE LOW PRESSURE IS CURRENTLY CRUISING TOWARDS THE GREAT
LAKES...WITH AN ATTENDANT COLD FRONT ALIGNED SOUTHWEST THROUGH THE
SOUTHERN PLAINS. ANOTHER LOW PRESSURE SYSTEM IS ORGANIZING ACROSS
THE NORTH CENTRAL GULF OF MEXICO...WITH HIGH PRESSURE RETREATING
OFF THE CAROLINA COAST. ALOFT...A SHORT WAVE TROUGH IS MOVING
ACROSS THE PLAINS WITHIN THE NORTHERN STREAM...WHILE ANOTHER ONE
IS MOVING THROUGH THE NORTH CENTRAL GULF WITHIN THE SOUTHERN
STREAM. THIS IS ALLOWING FOR DEEPER SOUTHWEST FLOW ACROSS THE MID
AND LOWER MISSISSIPPI VALLEY...WITH PLENTY OF HIGH CLOUDS
STREAMING IN FROM THE SOUTHWEST. EASTERN KENTUCKY REMAINS UNDER
PARTLY CLOUDY TO MOSTLY CLEAR SKIES...WITH TEMPERATURES VARYING
FROM THE MID TO UPPER 40S IN THE BROADER VALLEYS AND
RIDGETOPS...WHILE SHELTERED VALLEYS IN THE EAST REMAIN SOME 20
DEGREES COLDER...IN THE MID TO UPPER 20S.
THE TWO AFOREMENTIONED SYSTEMS WILL TRACK EAST TODAY...WITH
EASTERN KENTUCKY REMAINING SPLIT BETWEEN THEM. THE MODELS HAVE
TRENDED A BIT DRIER WITH THE SOUTHERN STREAM MOISTURE...KEEPING
MOST OF THIS JUST TO OUR SOUTHEAST. MOST OF THE FORCING WILL COME
FROM THE NORTHERN STREAM SYSTEM AS THE TROUGH AXIS AND SURFACE
COLD FRONT APPROACH FROM THE WEST. LIGHT RAIN SHOWERS WILL MOVE IN
FROM THE WEST TODAY...WITH THE MAJORITY OF THE ACTIVITY HOLDING
OFF UNTIL THIS AFTERNOON. THE BEST OVERALL RAIN CHANCES STILL LOOK
TO OCCUR IN THE FAR WEST...WITH LESSER CHANCES IN OUR NORTHEAST
COUNTIES. HIGHS TODAY WILL RECOVER INTO THE LOW TO MID 50S...WITH
SOME SPOTS REACHING THE UPPER 50S IN THE EAST...WHERE THICKER
CLOUD COVER WILL HOLD OFF THE LONGEST.
THE COLD FRONT AND TROUGH AXIS WILL SWING THROUGH THE AREA BETWEEN
00 AND 06Z TONIGHT...WITH A GOOD CHANCE OF LIGHT PRECIPITATION
CONTINUING. COLD ADVECTION WILL BE UNDERWAY OVERNIGHT...WITH LOWS
FOR MOST COOLING OFF TO THE LOW TO MID 30S. THE ONLY EXCEPTION
WILL BE THE HIGHER TERRAIN...WHERE LOWS WILL SETTLE INTO THE 20S.
HAVE LEFT A MENTION OF SNOW IN THE FORECAST TOWARDS DAWN SATURDAY
MORNING...HOWEVER WITH ICE IN QUESTION...DRIZZLE AND OR FREEZING
DRIZZLE MAY BECOME A CONCERN FOR THE HIGHER ELEVATIONS.
ANY LIGHT PRECIPITATION LINGERING INTO SATURDAY WILL TAPER OFF
DURING THE DAY AS FORCING DIMINISHES. HIGH TEMPERATURES WILL NOT
RECOVER MUCH DURING THE DAY WITH THICK CLOUD COVER LOCKED INTO
PLACE THANKS TO A POST-FRONTAL INVERSION. HAVE UNDERCUT THE
BLENDED GUIDANCE FOR THE HIGHS...ONLY ALLOWING FOR A FEW DEGREE
OR SO RISE FROM SATURDAY MORNING LOWS.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 344 AM EST FRI JAN 15 2016
...COLDEST AIR OF SEASON LIKELY SUNDAY NIGHT THROUGH MONDAY NIGHT...
MODELS REMAIN IN DECENT AGREEMENT ON THE MID/UPPER LEVEL PATTERN
THROUGH TUESDAY...BUT REMAIN FARTHER APART FROM WEDNESDAY ONWARD.
THE MAIN HEADLINE THROUGH THE EXTENDED WILL BE THE ARCTIC COLD FOR
EARLY NEXT WEEK.
SATURDAY NIGHT INTO SUNDAY...A QUICK MOVING SHORTWAVE TROUGH WILL
CROSS THE SOUTHERN APPALACHIANS AND COULD SEND SOME LIGHT SNOW
ACROSS SOUTHEAST KENTUCKY EARLY SUNDAY MORNING. STILL SOME QUESTION
ON HOW FAR BACK TO THE NORTHWEST THE SNOWFALL EXTENDS...BUT OUR
COUNTIES BORDERING VIRGINIA STAND A DECENT CHANCE TO SEE SOME LIGHT
SNOW AND POTENTIALLY A LIGHT COATING OF SNOW. THIS SYSTEM WILL BE
FASTER MOVING...SO SNOW CHANCES WILL QUICKLY DIMINISH SUNDAY
MORNING WITH CLOUDS POSSIBLY PARTING WAYS BY LATE MORNING INTO THE
AFTERNOON. WITH SOME SUNSHINE...CERTAINLY POSSIBLE HIGHS WILL MAKE
A BOUNCE UP IN TO THE MID TO UPPER 30S.
AN ARCTIC FRONT WILL THEN DROP SOUTH SUNDAY EVENING WITH COLD AIR
SURGING ACROSS KENTUCKY. LOWS BY MONDAY MORNING WILL BE WELL INTO
THE TEENS AND WE MAY NOT SEE TEMPERATURES CLIMB MUCH AT ALL ON
MONDAY. MOISTURE WITH THE FRONT REMAINS VERY LIMITED...AND
WOULDN`T EXPECT MORE THAN SOME FLURRIES WITH THE FRONTAL PASSAGE.
GIVEN THE COLD AIR...WE COULD MAINTAIN SOME FLURRIES WELL INTO
MONDAY MORNING...EVEN WITH THE LACK OF DECENT CLOUD COVER.
SHOULDN`T TAKE MUCH WITH USPLOPE FLOW TO SQUEEZE OUT FLURRIES IN
THIS COLD AIR MASS. BY MONDAY NIGHT...HIGH PRESSURE WILL BUILD
INTO THE REGION WITH LOWS FALLING TO AROUND ZERO IN THE
VALLEYS...SETTING UP THE COLDEST NIGHT THUS FAR THIS WINTER. WITH
THE HELP OF SUNSHINE ON TUESDAY WE SHOULD SEE TEMPERATURES CLIMB
BACK INTO THE 20S.
00Z ECMWF TRENDED SLIGHTLY TOWARDS THE GFS SOLUTION OF A CLIPPER
SYSTEM FOR WEDNESDAY. THIS WOULD SUPPORT SOME LIGHT SNOW
OVERSPREADING THE AREA ON WEDNESDAY WITH SOME LIGHT SNOW
ACCUMULATIONS POSSIBLE. TEMPERATURES MAY CREEP ABOVE FREEZING ON
WEDNESDAY...BUT ANY PRECIPITATION WILL REMAIN ALL SNOW BASED ON THE
TOP DOWN METHOD ON THE SOUNDING. WITH THE ECMWF TRENDING TOWARDS THE
GFS...WE MAY DRY THINGS OUT LATE WEDNESDAY NIGHT INTO THURSDAY
BEFORE ANOTHER SYSTEM POSSIBLY MOVES INTO THE REGION LATE IN THE
WEEK. REGARDLESS...MODELS STILL REMAIN FAR APART...SO WILL JUST
BRING IN SOME SLIGHT CHANCE POPS TOWARDS THE TAIL END OF THE
FORECAST AND LEAVE THEM FAIRLY LOW WITH THIS DEGREE OF LOW
CONFIDENCE. IT DOES APPEAR TEMPERATURES SHOULD WARM LATE IN THE
WEEK...SUPPORTING AN ALL RAIN EVENT IF A SYSTEM DOES MATERIALIZE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 110 PM EST FRI JAN 15 2016
RAIN WILL MOVE THROUGH THE FAR SOUTHEAST PART OF THE FORECAST AREA
THIS AFTERNOON...WITH THE STEADY RAIN THEN EXITING INTO WV BY
AROUND 23Z. MEANWHILE... ANOTHER AREA OF RAIN ASSOCIATED WITH A
COLD FRONT OVER CENTRAL KY AT MID DAY WILL MOVE EAST. THIS WILL
MOVE THROUGH THE JKL FORECAST AREA FROM ABOUT 22Z-03Z...
DISSIPATING AT THE SAME TIME. ONCE THE COLD FRONT MOVES THROUGH
THIS EVENING...DRIZZLE WILL BE POSSIBLE AT TIMES THROUGH THE
REMAINDER OF THE PERIOD...AND SOME FLURRIES OR EVEN FREEZING
DRIZZLE CAN NOT BE RULED OUT AS TEMPERATURES FALL TO NEAR FREEZING
AROUND DAWN.
CONDITIONS SHOULD LARGELY BE VFR UNTIL EARLY THIS EVENING...WITH
THE EXCEPTION OF SOME MVFR NEAR THE VA BORDER. AS THE COLD FRONT
MOVES THROUGH THIS EVENING...CONDITIONS ARE EXPECTED TO
DETERIORATE TO IFR AND REMAIN THERE THROUGH MOST OF THE REMAINDER
OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GEOGERIAN
LONG TERM...KAS
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
110 PM EST FRI JAN 15 2016
.UPDATE...
ISSUED AT 1157 AM EST FRI JAN 15 2016
SYSTEM MOVING THROUGH THE SE CONUS WILL END UP HAVING A GREATER
INFLUENCE ON OUR LOCAL AREA THAN EARLIER FORECAST. RAIN IS
SPREADING INTO OUR FAR SOUTHEAST COUNTIES...AND POPS HAVE BEEN
RAISED THERE FOR TODAY. WET BULB TEMPERATURES OVER THE HIGH
ELEVATIONS NEAR THE VA BORDER ARE BELOW FREEZING...AND THIS COULD
ALLOW FOR SOME SNOW TO INITIALLY OCCUR AS PRECIP MOVES IN...BUT IT
SHOULD FADE AWAY AS WET BULB READINGS EVENTUALLY RISE.
MEANWHILE... PRECIP OVER CENTRAL KY AHEAD OF A COLD FRONT HAS BEEN
SLOWER TO MAKE ITS WAY EAST THAN WAS EXPECTED...AND HAVE LOWERED
POPS TODAY AND HELD PRECIP OFF LONGER IN THE NW PART OF THE AREA.
WHAT IS LEFT OF THE FRONTAL PRECIP WILL MAKE ITS WAY ACROSS THE
REMAINDER OF OUR AREA...ESPECIALLY THE NORTH...THIS EVENING.
BEHIND THE COLD FRONT...POTENTIAL FOR PRECIP AND ITS TYPE REMAIN
ISSUES. MOISTURE WILL BE SHALLOW AND MAY NOT REACH -10C FOR ICE
FORMATION. HOWEVER...SURFACE TEMPS SHOULD EVENTUALLY REACH
FREEZING FOR SOME LOCATIONS. PRECIP TYPE COULD END UP BEING
DRIZZLE...FREEZING DRIZZLE...FLURRIES...OR SOME COMBINATION. AT
THIS POINT...HAVE ONLY USED SLIGHT CHANCE WORDING FOR THE
NONMEASURABLE PRECIP FROM LATE TONIGHT INTO SATURDAY NIGHT.
UPDATE ISSUED AT 751 AM EST FRI JAN 15 2016
FRESHENED UP THE HOURLY TEMPERATURES AND DEW POINTS. SHELTERED
VALLEYS ARE RANGING FROM THE MID 20S TO THE LOWER 30S...WITH MOST
OTHER LOCATIONS REPORTING IN THE LOW TO MID 40S. THICKER CLOUDS
ARE STARTING TO OVERTAKE THE AREA...WITH RAIN SHOWERS MOVING IN
ACROSS PORTIONS OF WESTERN KENTUCKY. THE LATEST HRRR GUIDANCE
CONTINUES TO SHOW LITTLE IN THE WAY OF SHOWER ACTIVITY UNTIL THIS
AFTERNOON...WHEN THE FAR SOUTHEAST MAY GET BRUSHED. WILL LET THE
CURRENT FORECAST RIDE FOR NOW. GRID UPDATES WILL BE FORTHCOMING.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 344 AM EST FRI JAN 15 2016
SURFACE LOW PRESSURE IS CURRENTLY CRUISING TOWARDS THE GREAT
LAKES...WITH AN ATTENDANT COLD FRONT ALIGNED SOUTHWEST THROUGH THE
SOUTHERN PLAINS. ANOTHER LOW PRESSURE SYSTEM IS ORGANIZING ACROSS
THE NORTH CENTRAL GULF OF MEXICO...WITH HIGH PRESSURE RETREATING
OFF THE CAROLINA COAST. ALOFT...A SHORT WAVE TROUGH IS MOVING
ACROSS THE PLAINS WITHIN THE NORTHERN STREAM...WHILE ANOTHER ONE
IS MOVING THROUGH THE NORTH CENTRAL GULF WITHIN THE SOUTHERN
STREAM. THIS IS ALLOWING FOR DEEPER SOUTHWEST FLOW ACROSS THE MID
AND LOWER MISSISSIPPI VALLEY...WITH PLENTY OF HIGH CLOUDS
STREAMING IN FROM THE SOUTHWEST. EASTERN KENTUCKY REMAINS UNDER
PARTLY CLOUDY TO MOSTLY CLEAR SKIES...WITH TEMPERATURES VARYING
FROM THE MID TO UPPER 40S IN THE BROADER VALLEYS AND
RIDGETOPS...WHILE SHELTERED VALLEYS IN THE EAST REMAIN SOME 20
DEGREES COLDER...IN THE MID TO UPPER 20S.
THE TWO AFOREMENTIONED SYSTEMS WILL TRACK EAST TODAY...WITH
EASTERN KENTUCKY REMAINING SPLIT BETWEEN THEM. THE MODELS HAVE
TRENDED A BIT DRIER WITH THE SOUTHERN STREAM MOISTURE...KEEPING
MOST OF THIS JUST TO OUR SOUTHEAST. MOST OF THE FORCING WILL COME
FROM THE NORTHERN STREAM SYSTEM AS THE TROUGH AXIS AND SURFACE
COLD FRONT APPROACH FROM THE WEST. LIGHT RAIN SHOWERS WILL MOVE IN
FROM THE WEST TODAY...WITH THE MAJORITY OF THE ACTIVITY HOLDING
OFF UNTIL THIS AFTERNOON. THE BEST OVERALL RAIN CHANCES STILL LOOK
TO OCCUR IN THE FAR WEST...WITH LESSER CHANCES IN OUR NORTHEAST
COUNTIES. HIGHS TODAY WILL RECOVER INTO THE LOW TO MID 50S...WITH
SOME SPOTS REACHING THE UPPER 50S IN THE EAST...WHERE THICKER
CLOUD COVER WILL HOLD OFF THE LONGEST.
THE COLD FRONT AND TROUGH AXIS WILL SWING THROUGH THE AREA BETWEEN
00 AND 06Z TONIGHT...WITH A GOOD CHANCE OF LIGHT PRECIPITATION
CONTINUING. COLD ADVECTION WILL BE UNDERWAY OVERNIGHT...WITH LOWS
FOR MOST COOLING OFF TO THE LOW TO MID 30S. THE ONLY EXCEPTION
WILL BE THE HIGHER TERRAIN...WHERE LOWS WILL SETTLE INTO THE 20S.
HAVE LEFT A MENTION OF SNOW IN THE FORECAST TOWARDS DAWN SATURDAY
MORNING...HOWEVER WITH ICE IN QUESTION...DRIZZLE AND OR FREEZING
DRIZZLE MAY BECOME A CONCERN FOR THE HIGHER ELEVATIONS.
ANY LIGHT PRECIPITATION LINGERING INTO SATURDAY WILL TAPER OFF
DURING THE DAY AS FORCING DIMINISHES. HIGH TEMPERATURES WILL NOT
RECOVER MUCH DURING THE DAY WITH THICK CLOUD COVER LOCKED INTO
PLACE THANKS TO A POST-FRONTAL INVERSION. HAVE UNDERCUT THE
BLENDED GUIDANCE FOR THE HIGHS...ONLY ALLOWING FOR A FEW DEGREE
OR SO RISE FROM SATURDAY MORNING LOWS.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 344 AM EST FRI JAN 15 2016
...COLDEST AIR OF SEASON LIKELY SUNDAY NIGHT THROUGH MONDAY NIGHT...
MODELS REMAIN IN DECENT AGREEMENT ON THE MID/UPPER LEVEL PATTERN
THROUGH TUESDAY...BUT REMAIN FARTHER APART FROM WEDNESDAY ONWARD.
THE MAIN HEADLINE THROUGH THE EXTENDED WILL BE THE ARCTIC COLD FOR
EARLY NEXT WEEK.
SATURDAY NIGHT INTO SUNDAY...A QUICK MOVING SHORTWAVE TROUGH WILL
CROSS THE SOUTHERN APPALACHIANS AND COULD SEND SOME LIGHT SNOW
ACROSS SOUTHEAST KENTUCKY EARLY SUNDAY MORNING. STILL SOME QUESTION
ON HOW FAR BACK TO THE NORTHWEST THE SNOWFALL EXTENDS...BUT OUR
COUNTIES BORDERING VIRGINIA STAND A DECENT CHANCE TO SEE SOME LIGHT
SNOW AND POTENTIALLY A LIGHT COATING OF SNOW. THIS SYSTEM WILL BE
FASTER MOVING...SO SNOW CHANCES WILL QUICKLY DIMINISH SUNDAY
MORNING WITH CLOUDS POSSIBLY PARTING WAYS BY LATE MORNING INTO THE
AFTERNOON. WITH SOME SUNSHINE...CERTAINLY POSSIBLE HIGHS WILL MAKE
A BOUNCE UP IN TO THE MID TO UPPER 30S.
AN ARCTIC FRONT WILL THEN DROP SOUTH SUNDAY EVENING WITH COLD AIR
SURGING ACROSS KENTUCKY. LOWS BY MONDAY MORNING WILL BE WELL INTO
THE TEENS AND WE MAY NOT SEE TEMPERATURES CLIMB MUCH AT ALL ON
MONDAY. MOISTURE WITH THE FRONT REMAINS VERY LIMITED...AND
WOULDN`T EXPECT MORE THAN SOME FLURRIES WITH THE FRONTAL PASSAGE.
GIVEN THE COLD AIR...WE COULD MAINTAIN SOME FLURRIES WELL INTO
MONDAY MORNING...EVEN WITH THE LACK OF DECENT CLOUD COVER.
SHOULDN`T TAKE MUCH WITH USPLOPE FLOW TO SQUEEZE OUT FLURRIES IN
THIS COLD AIR MASS. BY MONDAY NIGHT...HIGH PRESSURE WILL BUILD
INTO THE REGION WITH LOWS FALLING TO AROUND ZERO IN THE
VALLEYS...SETTING UP THE COLDEST NIGHT THUS FAR THIS WINTER. WITH
THE HELP OF SUNSHINE ON TUESDAY WE SHOULD SEE TEMPERATURES CLIMB
BACK INTO THE 20S.
00Z ECMWF TRENDED SLIGHTLY TOWARDS THE GFS SOLUTION OF A CLIPPER
SYSTEM FOR WEDNESDAY. THIS WOULD SUPPORT SOME LIGHT SNOW
OVERSPREADING THE AREA ON WEDNESDAY WITH SOME LIGHT SNOW
ACCUMULATIONS POSSIBLE. TEMPERATURES MAY CREEP ABOVE FREEZING ON
WEDNESDAY...BUT ANY PRECIPITATION WILL REMAIN ALL SNOW BASED ON THE
TOP DOWN METHOD ON THE SOUNDING. WITH THE ECMWF TRENDING TOWARDS THE
GFS...WE MAY DRY THINGS OUT LATE WEDNESDAY NIGHT INTO THURSDAY
BEFORE ANOTHER SYSTEM POSSIBLY MOVES INTO THE REGION LATE IN THE
WEEK. REGARDLESS...MODELS STILL REMAIN FAR APART...SO WILL JUST
BRING IN SOME SLIGHT CHANCE POPS TOWARDS THE TAIL END OF THE
FORECAST AND LEAVE THEM FAIRLY LOW WITH THIS DEGREE OF LOW
CONFIDENCE. IT DOES APPEAR TEMPERATURES SHOULD WARM LATE IN THE
WEEK...SUPPORTING AN ALL RAIN EVENT IF A SYSTEM DOES MATERIALIZE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 110 PM EST FRI JAN 15 2016
RAIN WILL MOVE THROUGH THE FAR SOUTHEAST PART OF THE FORECAST AREA
THIS AFTERNOON...WITH THE STEADY RAIN THEN EXITING INTO WV BY
AROUND 23Z. MEANWHILE... ANOTHER AREA OF RAIN ASSOCIATED WITH A
COLD FRONT OVER CENTRAL KY AT MID DAY WILL MOVE EAST. THIS WILL
MOVE THROUGH THE JKL FORECAST AREA FROM ABOUT 22Z-03Z...
DISSIPATING AT THE SAME TIME. ONCE THE COLD FRONT MOVES THROUGH
THIS EVENING...DRIZZLE WILL BE POSSIBLE AT TIMES THROUGH THE
REMAINDER OF THE PERIOD...AND SOME FLURRIES OR EVEN FREEZING
DRIZZLE CAN NOT BE RULED OUT AS TEMPERATURES FALL TO NEAR FREEZING
AROUND DAWN.
CONDITIONS SHOULD LARGELY BE VFR UNTIL EARLY THIS EVENING...WITH
THE EXCEPTION OF SOME MVFR NEAR THE VA BORDER. AS THE COLD FRONT
MOVES THROUGH THIS EVENING...CONDITIONS ARE EXPECTED TO
DETERIORATE TO IFR AND REMAIN THERE THROUGH MOST OF THE REMAINDER
OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GEOGERIAN
LONG TERM...KAS
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
1157 AM EST FRI JAN 15 2016
.UPDATE...
ISSUED AT 1157 AM EST FRI JAN 15 2016
SYSTEM MOVING THROUGH THE SE CONUS WILL END UP HAVING A GREATER
INFLUENCE ON OUR LOCAL AREA THAN EARLIER FORECAST. RAIN IS
SPREADING INTO OUR FAR SOUTHEAST COUNTIES...AND POPS HAVE BEEN
RAISED THERE FOR TODAY. WET BULB TEMPERATURES OVER THE HIGH
ELEVATIONS NEAR THE VA BORDER ARE BELOW FREEZING...AND THIS COULD
ALLOW FOR SOME SNOW TO INITIALLY OCCUR AS PRECIP MOVES IN...BUT IT
SHOULD FADE AWAY AS WET BULB READINGS EVENTUALLY RISE.
MEANWHILE... PRECIP OVER CENTRAL KY AHEAD OF A COLD FRONT HAS BEEN
SLOWER TO MAKE ITS WAY EAST THAN WAS EXPECTED...AND HAVE LOWERED
POPS TODAY AND HELD PRECIP OFF LONGER IN THE NW PART OF THE AREA.
WHAT IS LEFT OF THE FRONTAL PRECIP WILL MAKE ITS WAY ACROSS THE
REMAINDER OF OUR AREA...ESPECIALLY THE NORTH...THIS EVENING.
BEHIND THE COLD FRONT...POTENTIAL FOR PRECIP AND ITS TYPE REMAIN
ISSUES. MOISTURE WILL BE SHALLOW AND MAY NOT REACH -10C FOR ICE
FORMATION. HOWEVER...SURFACE TEMPS SHOULD EVENTUALLY REACH
FREEZING FOR SOME LOCATIONS. PRECIP TYPE COULD END UP BEING
DRIZZLE...FREEZING DRIZZLE...FLURRIES...OR SOME COMBINATION. AT
THIS POINT...HAVE ONLY USED SLIGHT CHANCE WORDING FOR THE
NONMEASURABLE PRECIP FROM LATE TONIGHT INTO SATURDAY NIGHT.
UPDATE ISSUED AT 751 AM EST FRI JAN 15 2016
FRESHENED UP THE HOURLY TEMPERATURES AND DEW POINTS. SHELTERED
VALLEYS ARE RANGING FROM THE MID 20S TO THE LOWER 30S...WITH MOST
OTHER LOCATIONS REPORTING IN THE LOW TO MID 40S. THICKER CLOUDS
ARE STARTING TO OVERTAKE THE AREA...WITH RAIN SHOWERS MOVING IN
ACROSS PORTIONS OF WESTERN KENTUCKY. THE LATEST HRRR GUIDANCE
CONTINUES TO SHOW LITTLE IN THE WAY OF SHOWER ACTIVITY UNTIL THIS
AFTERNOON...WHEN THE FAR SOUTHEAST MAY GET BRUSHED. WILL LET THE
CURRENT FORECAST RIDE FOR NOW. GRID UPDATES WILL BE FORTHCOMING.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 344 AM EST FRI JAN 15 2016
SURFACE LOW PRESSURE IS CURRENTLY CRUISING TOWARDS THE GREAT
LAKES...WITH AN ATTENDANT COLD FRONT ALIGNED SOUTHWEST THROUGH THE
SOUTHERN PLAINS. ANOTHER LOW PRESSURE SYSTEM IS ORGANIZING ACROSS
THE NORTH CENTRAL GULF OF MEXICO...WITH HIGH PRESSURE RETREATING
OFF THE CAROLINA COAST. ALOFT...A SHORT WAVE TROUGH IS MOVING
ACROSS THE PLAINS WITHIN THE NORTHERN STREAM...WHILE ANOTHER ONE
IS MOVING THROUGH THE NORTH CENTRAL GULF WITHIN THE SOUTHERN
STREAM. THIS IS ALLOWING FOR DEEPER SOUTHWEST FLOW ACROSS THE MID
AND LOWER MISSISSIPPI VALLEY...WITH PLENTY OF HIGH CLOUDS
STREAMING IN FROM THE SOUTHWEST. EASTERN KENTUCKY REMAINS UNDER
PARTLY CLOUDY TO MOSTLY CLEAR SKIES...WITH TEMPERATURES VARYING
FROM THE MID TO UPPER 40S IN THE BROADER VALLEYS AND
RIDGETOPS...WHILE SHELTERED VALLEYS IN THE EAST REMAIN SOME 20
DEGREES COLDER...IN THE MID TO UPPER 20S.
THE TWO AFOREMENTIONED SYSTEMS WILL TRACK EAST TODAY...WITH
EASTERN KENTUCKY REMAINING SPLIT BETWEEN THEM. THE MODELS HAVE
TRENDED A BIT DRIER WITH THE SOUTHERN STREAM MOISTURE...KEEPING
MOST OF THIS JUST TO OUR SOUTHEAST. MOST OF THE FORCING WILL COME
FROM THE NORTHERN STREAM SYSTEM AS THE TROUGH AXIS AND SURFACE
COLD FRONT APPROACH FROM THE WEST. LIGHT RAIN SHOWERS WILL MOVE IN
FROM THE WEST TODAY...WITH THE MAJORITY OF THE ACTIVITY HOLDING
OFF UNTIL THIS AFTERNOON. THE BEST OVERALL RAIN CHANCES STILL LOOK
TO OCCUR IN THE FAR WEST...WITH LESSER CHANCES IN OUR NORTHEAST
COUNTIES. HIGHS TODAY WILL RECOVER INTO THE LOW TO MID 50S...WITH
SOME SPOTS REACHING THE UPPER 50S IN THE EAST...WHERE THICKER
CLOUD COVER WILL HOLD OFF THE LONGEST.
THE COLD FRONT AND TROUGH AXIS WILL SWING THROUGH THE AREA BETWEEN
00 AND 06Z TONIGHT...WITH A GOOD CHANCE OF LIGHT PRECIPITATION
CONTINUING. COLD ADVECTION WILL BE UNDERWAY OVERNIGHT...WITH LOWS
FOR MOST COOLING OFF TO THE LOW TO MID 30S. THE ONLY EXCEPTION
WILL BE THE HIGHER TERRAIN...WHERE LOWS WILL SETTLE INTO THE 20S.
HAVE LEFT A MENTION OF SNOW IN THE FORECAST TOWARDS DAWN SATURDAY
MORNING...HOWEVER WITH ICE IN QUESTION...DRIZZLE AND OR FREEZING
DRIZZLE MAY BECOME A CONCERN FOR THE HIGHER ELEVATIONS.
ANY LIGHT PRECIPITATION LINGERING INTO SATURDAY WILL TAPER OFF
DURING THE DAY AS FORCING DIMINISHES. HIGH TEMPERATURES WILL NOT
RECOVER MUCH DURING THE DAY WITH THICK CLOUD COVER LOCKED INTO
PLACE THANKS TO A POST-FRONTAL INVERSION. HAVE UNDERCUT THE
BLENDED GUIDANCE FOR THE HIGHS...ONLY ALLOWING FOR A FEW DEGREE
OR SO RISE FROM SATURDAY MORNING LOWS.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 344 AM EST FRI JAN 15 2016
...COLDEST AIR OF SEASON LIKELY SUNDAY NIGHT THROUGH MONDAY NIGHT...
MODELS REMAIN IN DECENT AGREEMENT ON THE MID/UPPER LEVEL PATTERN
THROUGH TUESDAY...BUT REMAIN FARTHER APART FROM WEDNESDAY ONWARD.
THE MAIN HEADLINE THROUGH THE EXTENDED WILL BE THE ARCTIC COLD FOR
EARLY NEXT WEEK.
SATURDAY NIGHT INTO SUNDAY...A QUICK MOVING SHORTWAVE TROUGH WILL
CROSS THE SOUTHERN APPALACHIANS AND COULD SEND SOME LIGHT SNOW
ACROSS SOUTHEAST KENTUCKY EARLY SUNDAY MORNING. STILL SOME QUESTION
ON HOW FAR BACK TO THE NORTHWEST THE SNOWFALL EXTENDS...BUT OUR
COUNTIES BORDERING VIRGINIA STAND A DECENT CHANCE TO SEE SOME LIGHT
SNOW AND POTENTIALLY A LIGHT COATING OF SNOW. THIS SYSTEM WILL BE
FASTER MOVING...SO SNOW CHANCES WILL QUICKLY DIMINISH SUNDAY
MORNING WITH CLOUDS POSSIBLY PARTING WAYS BY LATE MORNING INTO THE
AFTERNOON. WITH SOME SUNSHINE...CERTAINLY POSSIBLE HIGHS WILL MAKE
A BOUNCE UP IN TO THE MID TO UPPER 30S.
AN ARCTIC FRONT WILL THEN DROP SOUTH SUNDAY EVENING WITH COLD AIR
SURGING ACROSS KENTUCKY. LOWS BY MONDAY MORNING WILL BE WELL INTO
THE TEENS AND WE MAY NOT SEE TEMPERATURES CLIMB MUCH AT ALL ON
MONDAY. MOISTURE WITH THE FRONT REMAINS VERY LIMITED...AND
WOULDN`T EXPECT MORE THAN SOME FLURRIES WITH THE FRONTAL PASSAGE.
GIVEN THE COLD AIR...WE COULD MAINTAIN SOME FLURRIES WELL INTO
MONDAY MORNING...EVEN WITH THE LACK OF DECENT CLOUD COVER.
SHOULDN`T TAKE MUCH WITH USPLOPE FLOW TO SQUEEZE OUT FLURRIES IN
THIS COLD AIR MASS. BY MONDAY NIGHT...HIGH PRESSURE WILL BUILD
INTO THE REGION WITH LOWS FALLING TO AROUND ZERO IN THE
VALLEYS...SETTING UP THE COLDEST NIGHT THUS FAR THIS WINTER. WITH
THE HELP OF SUNSHINE ON TUESDAY WE SHOULD SEE TEMPERATURES CLIMB
BACK INTO THE 20S.
00Z ECMWF TRENDED SLIGHTLY TOWARDS THE GFS SOLUTION OF A CLIPPER
SYSTEM FOR WEDNESDAY. THIS WOULD SUPPORT SOME LIGHT SNOW
OVERSPREADING THE AREA ON WEDNESDAY WITH SOME LIGHT SNOW
ACCUMULATIONS POSSIBLE. TEMPERATURES MAY CREEP ABOVE FREEZING ON
WEDNESDAY...BUT ANY PRECIPITATION WILL REMAIN ALL SNOW BASED ON THE
TOP DOWN METHOD ON THE SOUNDING. WITH THE ECMWF TRENDING TOWARDS THE
GFS...WE MAY DRY THINGS OUT LATE WEDNESDAY NIGHT INTO THURSDAY
BEFORE ANOTHER SYSTEM POSSIBLY MOVES INTO THE REGION LATE IN THE
WEEK. REGARDLESS...MODELS STILL REMAIN FAR APART...SO WILL JUST
BRING IN SOME SLIGHT CHANCE POPS TOWARDS THE TAIL END OF THE
FORECAST AND LEAVE THEM FAIRLY LOW WITH THIS DEGREE OF LOW
CONFIDENCE. IT DOES APPEAR TEMPERATURES SHOULD WARM LATE IN THE
WEEK...SUPPORTING AN ALL RAIN EVENT IF A SYSTEM DOES MATERIALIZE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 751 AM EST FRI JAN 15 2016
VFR CONDITIONS WILL HOLD ON THROUGH EARLY THIS AFTERNOON...WITH
MAINLY JUST PASSING HIGH CLOUDS TO CONTEND WITH UNTIL AFTER 18Z.
CEILINGS WILL THEN LOWER MORE QUICKLY DOWN TO MVFR FROM WEST TO
EAST...BETWEEN 21Z AND 00Z SATURDAY...WITH LIGHT RAIN SHOWERS
MOVING IN FROM THE WEST. A COLD FRONT WILL PASS THROUGH THIS
EVENING...WITH CEILINGS DROPPING DOWN TO IFR BEHIND THE BOUNDARY.
VERY LIGHT RAIN/DRIZZLE WILL LIKELY PERSIST INTO THE OVERNIGHT.
SOUTH WINDS OF 5 TO 10 KTS WILL REMAIN IN PLACE UNTIL THE FRONTAL
PASSAGE BETWEEN 00Z AND 06Z SATURDAY...WITH WINDS THEN TURNING
MORE TO THE WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...GEOGERIAN
LONG TERM...KAS
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
751 AM EST FRI JAN 15 2016
.UPDATE...
ISSUED AT 751 AM EST FRI JAN 15 2016
FRESHENED UP THE HOURLY TEMPERATURES AND DEW POINTS. SHELTERED
VALLEYS ARE RANGING FROM THE MID 20S TO THE LOWER 30S...WITH MOST
OTHER LOCATIONS REPORTING IN THE LOW TO MID 40S. THICKER CLOUDS
ARE STARTING TO OVERTAKE THE AREA...WITH RAIN SHOWERS MOVING IN
ACROSS PORTIONS OF WESTERN KENTUCKY. THE LATEST HRRR GUIDANCE
CONTINUES TO SHOW LITTLE IN THE WAY OF SHOWER ACTIVITY UNTIL THIS
AFTERNOON...WHEN THE FAR SOUTHEAST MAY GET BRUSHED. WILL LET THE
CURRENT FORECAST RIDE FOR NOW. GRID UPDATES WILL BE FORTHCOMING.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 344 AM EST FRI JAN 15 2016
SURFACE LOW PRESSURE IS CURRENTLY CRUISING TOWARDS THE GREAT
LAKES...WITH AN ATTENDANT COLD FRONT ALIGNED SOUTHWEST THROUGH THE
SOUTHERN PLAINS. ANOTHER LOW PRESSURE SYSTEM IS ORGANIZING ACROSS
THE NORTH CENTRAL GULF OF MEXICO...WITH HIGH PRESSURE RETREATING
OFF THE CAROLINA COAST. ALOFT...A SHORT WAVE TROUGH IS MOVING
ACROSS THE PLAINS WITHIN THE NORTHERN STREAM...WHILE ANOTHER ONE
IS MOVING THROUGH THE NORTH CENTRAL GULF WITHIN THE SOUTHERN
STREAM. THIS IS ALLOWING FOR DEEPER SOUTHWEST FLOW ACROSS THE MID
AND LOWER MISSISSIPPI VALLEY...WITH PLENTY OF HIGH CLOUDS
STREAMING IN FROM THE SOUTHWEST. EASTERN KENTUCKY REMAINS UNDER
PARTLY CLOUDY TO MOSTLY CLEAR SKIES...WITH TEMPERATURES VARYING
FROM THE MID TO UPPER 40S IN THE BROADER VALLEYS AND
RIDGETOPS...WHILE SHELTERED VALLEYS IN THE EAST REMAIN SOME 20
DEGREES COLDER...IN THE MID TO UPPER 20S.
THE TWO AFOREMENTIONED SYSTEMS WILL TRACK EAST TODAY...WITH
EASTERN KENTUCKY REMAINING SPLIT BETWEEN THEM. THE MODELS HAVE
TRENDED A BIT DRIER WITH THE SOUTHERN STREAM MOISTURE...KEEPING
MOST OF THIS JUST TO OUR SOUTHEAST. MOST OF THE FORCING WILL COME
FROM THE NORTHERN STREAM SYSTEM AS THE TROUGH AXIS AND SURFACE
COLD FRONT APPROACH FROM THE WEST. LIGHT RAIN SHOWERS WILL MOVE IN
FROM THE WEST TODAY...WITH THE MAJORITY OF THE ACTIVITY HOLDING
OFF UNTIL THIS AFTERNOON. THE BEST OVERALL RAIN CHANCES STILL LOOK
TO OCCUR IN THE FAR WEST...WITH LESSER CHANCES IN OUR NORTHEAST
COUNTIES. HIGHS TODAY WILL RECOVER INTO THE LOW TO MID 50S...WITH
SOME SPOTS REACHING THE UPPER 50S IN THE EAST...WHERE THICKER
CLOUD COVER WILL HOLD OFF THE LONGEST.
THE COLD FRONT AND TROUGH AXIS WILL SWING THROUGH THE AREA BETWEEN
00 AND 06Z TONIGHT...WITH A GOOD CHANCE OF LIGHT PRECIPITATION
CONTINUING. COLD ADVECTION WILL BE UNDERWAY OVERNIGHT...WITH LOWS
FOR MOST COOLING OFF TO THE LOW TO MID 30S. THE ONLY EXCEPTION
WILL BE THE HIGHER TERRAIN...WHERE LOWS WILL SETTLE INTO THE 20S.
HAVE LEFT A MENTION OF SNOW IN THE FORECAST TOWARDS DAWN SATURDAY
MORNING...HOWEVER WITH ICE IN QUESTION...DRIZZLE AND OR FREEZING
DRIZZLE MAY BECOME A CONCERN FOR THE HIGHER ELEVATIONS.
ANY LIGHT PRECIPITATION LINGERING INTO SATURDAY WILL TAPER OFF
DURING THE DAY AS FORCING DIMINISHES. HIGH TEMPERATURES WILL NOT
RECOVER MUCH DURING THE DAY WITH THICK CLOUD COVER LOCKED INTO
PLACE THANKS TO A POST-FRONTAL INVERSION. HAVE UNDERCUT THE
BLENDED GUIDANCE FOR THE HIGHS...ONLY ALLOWING FOR A FEW DEGREE
OR SO RISE FROM SATURDAY MORNING LOWS.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 344 AM EST FRI JAN 15 2016
...COLDEST AIR OF SEASON LIKELY SUNDAY NIGHT THROUGH MONDAY NIGHT...
MODELS REMAIN IN DECENT AGREEMENT ON THE MID/UPPER LEVEL PATTERN
THROUGH TUESDAY...BUT REMAIN FARTHER APART FROM WEDNESDAY ONWARD.
THE MAIN HEADLINE THROUGH THE EXTENDED WILL BE THE ARCTIC COLD FOR
EARLY NEXT WEEK.
SATURDAY NIGHT INTO SUNDAY...A QUICK MOVING SHORTWAVE TROUGH WILL
CROSS THE SOUTHERN APPALACHIANS AND COULD SEND SOME LIGHT SNOW
ACROSS SOUTHEAST KENTUCKY EARLY SUNDAY MORNING. STILL SOME QUESTION
ON HOW FAR BACK TO THE NORTHWEST THE SNOWFALL EXTENDS...BUT OUR
COUNTIES BORDERING VIRGINIA STAND A DECENT CHANCE TO SEE SOME LIGHT
SNOW AND POTENTIALLY A LIGHT COATING OF SNOW. THIS SYSTEM WILL BE
FASTER MOVING...SO SNOW CHANCES WILL QUICKLY DIMINISH SUNDAY
MORNING WITH CLOUDS POSSIBLY PARTING WAYS BY LATE MORNING INTO THE
AFTERNOON. WITH SOME SUNSHINE...CERTAINLY POSSIBLE HIGHS WILL MAKE
A BOUNCE UP IN TO THE MID TO UPPER 30S.
AN ARCTIC FRONT WILL THEN DROP SOUTH SUNDAY EVENING WITH COLD AIR
SURGING ACROSS KENTUCKY. LOWS BY MONDAY MORNING WILL BE WELL INTO
THE TEENS AND WE MAY NOT SEE TEMPERATURES CLIMB MUCH AT ALL ON
MONDAY. MOISTURE WITH THE FRONT REMAINS VERY LIMITED...AND
WOULDN`T EXPECT MORE THAN SOME FLURRIES WITH THE FRONTAL PASSAGE.
GIVEN THE COLD AIR...WE COULD MAINTAIN SOME FLURRIES WELL INTO
MONDAY MORNING...EVEN WITH THE LACK OF DECENT CLOUD COVER.
SHOULDN`T TAKE MUCH WITH USPLOPE FLOW TO SQUEEZE OUT FLURRIES IN
THIS COLD AIR MASS. BY MONDAY NIGHT...HIGH PRESSURE WILL BUILD
INTO THE REGION WITH LOWS FALLING TO AROUND ZERO IN THE
VALLEYS...SETTING UP THE COLDEST NIGHT THUS FAR THIS WINTER. WITH
THE HELP OF SUNSHINE ON TUESDAY WE SHOULD SEE TEMPERATURES CLIMB
BACK INTO THE 20S.
00Z ECMWF TRENDED SLIGHTLY TOWARDS THE GFS SOLUTION OF A CLIPPER
SYSTEM FOR WEDNESDAY. THIS WOULD SUPPORT SOME LIGHT SNOW
OVERSPREADING THE AREA ON WEDNESDAY WITH SOME LIGHT SNOW
ACCUMULATIONS POSSIBLE. TEMPERATURES MAY CREEP ABOVE FREEZING ON
WEDNESDAY...BUT ANY PRECIPITATION WILL REMAIN ALL SNOW BASED ON THE
TOP DOWN METHOD ON THE SOUNDING. WITH THE ECMWF TRENDING TOWARDS THE
GFS...WE MAY DRY THINGS OUT LATE WEDNESDAY NIGHT INTO THURSDAY
BEFORE ANOTHER SYSTEM POSSIBLY MOVES INTO THE REGION LATE IN THE
WEEK. REGARDLESS...MODELS STILL REMAIN FAR APART...SO WILL JUST
BRING IN SOME SLIGHT CHANCE POPS TOWARDS THE TAIL END OF THE
FORECAST AND LEAVE THEM FAIRLY LOW WITH THIS DEGREE OF LOW
CONFIDENCE. IT DOES APPEAR TEMPERATURES SHOULD WARM LATE IN THE
WEEK...SUPPORTING AN ALL RAIN EVENT IF A SYSTEM DOES MATERIALIZE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 751 AM EST FRI JAN 15 2016
VFR CONDITIONS WILL HOLD ON THROUGH EARLY THIS AFTERNOON...WITH
MAINLY JUST PASSING HIGH CLOUDS TO CONTEND WITH UNTIL AFTER 18Z.
CEILINGS WILL THEN LOWER MORE QUICKLY DOWN TO MVFR FROM WEST TO
EAST...BETWEEN 21Z AND 00Z SATURDAY...WITH LIGHT RAIN SHOWERS
MOVING IN FROM THE WEST. A COLD FRONT WILL PASS THROUGH THIS
EVENING...WITH CEILINGS DROPPING DOWN TO IFR BEHIND THE BOUNDARY.
VERY LIGHT RAIN/DRIZZLE WILL LIKELY PERSIST INTO THE OVERNIGHT.
SOUTH WINDS OF 5 TO 10 KTS WILL REMAIN IN PLACE UNTIL THE FRONTAL
PASSAGE BETWEEN 00Z AND 06Z SATURDAY...WITH WINDS THEN TURNING
MORE TO THE WEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...GEOGERIAN
LONG TERM...KAS
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
800 PM EST SAT JAN 16 2016
.UPDATE...
ARCTIC FRONT WAS POSITIONED FROM ABOUT THE BRIDGE TO MBL TO
CHICAGO. THIS FRONT WILL MOVE THROUGH THE FORECAST AREA AFTER
MIDNIGHT. TOOK OUT THE MENTION OF SNOW SHOWERS UNTIL THE FRONT
GETS CLOSER. AT THE TIME OF FRONTAL PASSAGE...A WEAK WAVE NOTED
OVER IA AND NRN IL...WILL INTERACT WITH THE FRONT. THE 18Z NAM
AND UPDATED RUC SUGGESTS SOME CHANCE OF MINOR QPF FOR AREAS AS FAR
NORTH AS M 46. WILL TAKE THE LATE NIGHT 50 POPS THAT WERE FOCUSED
FARTHER SOUTH AFTER 09Z...AND MOVE THEM TO 06Z TO 12Z AND EXPAND
THEM NORTH TO HIGHWAY M 46.
OTHERWISE FORECAST ON TRACK TONIGHT WITH CLOUDS AND LOW TEMPS. DID
TWEAK THE WIND UP JUST A NOTCH GIVEN THE GRADIENT AND THE COLD
AIR SPILLING INTO LOWER MICHIGAN. THAT COLD AIR APPEARS TO HAVE
SOME ABILITY TO KEEP A MIX LAYER WITH SOME DEPTH.
&&
.AVIATION...ISSUED 626 PM EST SAT JAN 16 2016
WIDESPREAD VFR CLOUDS IN RESPONSE TO BOTH THE LAKE EFFECT OFF OF
LAKE MI AND THE ARCTIC FRONT JUST ENTERING LOWER MI. CEILINGS SHOULD
LOWER WITH A LOWERING OVERNIGHT INVERSION...BUT RIGHT AT MVFR/VFR
AROUND 3K FEET. BEST CHANCE OF SNOW WITH MVFR VISIBILITIES LOOKS TO
BE WITH THE PASSAGE OF THE ARCTIC FRONT FROM 06Z TO 11Z FROM FNT TO
MAYBE THE DETROIT AREA TAF SITES...AND THEN AGAIN FROM 11Z TO 15Z
WITH THE UPPER WAVE PASSING JUST SOUTH OF THE STATE. MAY TAKE UNTIL
THE LATER AFTERNOON OR EVENING TO GET THE LAKE EFFECT FROM LAKE MI
OVER TO SE LOWER MI. WINDS WILL BE WSW UNTIL THE FRONTAL PASSAGE AND
THEN JUST A SLIGHT SHIFT TO WEST WINDS. GRADIENT AND COLD AIR
SURGING INTO THE REGION WILL KEEP WINDS UP AROUND 15 KTS THROUGH THE
FORECAST PERIOD. DURING THE DAYLIGHT HOURS ON SUNDAY WITH MORE
MIXING...EXPECT GUSTS TO GET TO 25 KTS.
FOR DTW... CEILINGS AROUND 3500-4000 FEET WITH NO PRECIP A SLIGHTLY
LESS WIND WILL BE PREDOMINANT FOR THE EVENING. MVFR CEILING AND
FLURRIES WILL BE MORE PERSISTENT ALONG AND BEHIND THE COLD FRONT
MOVING THROUGH AFTER MIDNIGHT. A SHORT WINDOW OF GREATER LAKE EFFECT
ACTIVITY IS POSSIBLE LATE TONIGHT AND SUNDAY MORNING PRODUCE
ACCUMULATION LESS THAN 1 INCH. WESTERLY FLOW FAVORS GREATER
CONCENTRATION OF SNOW SHOWERS SETTLING NORTH TOWARD PTK. WITH SOME
MIXING ON SUNDAY...WESTERLY WINDS INCREASE TO AROUND 15 KTS WITH
GUST GETTING TO 25 KTS.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILING AOB 5KFT TONIGHT AND SUNDAY.
* HIGH FOR SNOW AS PTYPE
* MODERATE FOR WESTERLY WIND GUSTS EXCEEDING CROSSWIND THRESHOLDS
SUNDAY.
&&
.PREV DISCUSSION...ISSUED 405 PM EST SAT JAN 16 2016
DISCUSSION...
FORECAST FOR THE REMAINDER OF THE HOLIDAY WEEKEND WILL BE DOMINATED
BY AN ARCTIC AIR INTRUSION THAT WILL OCCUR TONIGHT AND SUNDAY AS A
LARGE UPPER LOW SLOWLY TRACKS THROUGH THE GREAT LAKES. THIS WILL
BRING VERY COLD TEMPERATURES...GUSTY WINDS/LOW WIND CHILLS...AND
CHANCES FOR SNOW SHOWERS.
AREA OF ENHANCED LAKE EFFECT...MAINLY IN ONE BAND...WITH CONNECTIONS
TO BOTH LAKE SUPERIOR AND LAKE MICHIGAN THAT AFFECTED PRIMARILY THE
SAGINAW VALLEY EARLY TODAY SHIFTED AS WINDS TURNED MORE WESTERLY.
LIGHT SHOWERS AND FLURRIES HAVE SINCE BEEN MAKING THEIR WAY INTO THE
EASTERN PART OF THE STATE THIS AFTERNOON...WITH LATEST
RADAR/SATELLITE INDICATING MOISTURE IS RELEASING OFF LAKE MICHIGAN.
WHAT IS LEFT OF THE SHOWERS/CLOUDS OVER THE WESTERN PART OF THE
STATE SHOULD MAKE THEIR WAY ACROSS SOUTHEAST MICHIGAN BETWEEN 4PM
AND 8PM. MAY THEN SEE SOME BREAKS OR CLEAR PATCHES IN CLOUDS AS
DRIER AIR EVIDENT ON SATELLITE OVER LAKE MICHIGAN AND EXTENDING BACK
THROUGH WISCONSIN WORKS THROUGH. DRIER AIR IS AT THE LEAD EDGE OF
ARCTIC AIRMASS THAT WILL SPILL INTO THE AREA FOR THE REMAINDER OF
THE WEEKEND. PRECIPITATION IS CURRENTLY NOT OCCURRING UPSTREAM IN
ASSOCIATION WITH THE FRONTAL PASSAGE. GIVEN THIS AIRMASS WILL BE
MOVING OVER A RELATIVELY WARM LAKE MICHIGAN...42 DEGREES PER LATEST
SATELLITE ANALYSIS...AND TEMPS ARE IN THE SINGLE DIGITS BEHIND THE
FRONT...WILL KEEP SOME LOW POPS IN THE FORECAST TO COVER ANY LAKE
EFFECT THAT STREAMS THIS FAR EAST.
UPTICK IN SNOW SHOWER ACTIVITY IS EXPECTED VERY LATE TONIGHT THROUGH
SUNDAY AFTERNOON AS DEEPER MOISTURE ARRIVES...COLD AIR ADVECTION
INCREASES LAKE RESPONSE...AND PVA ASSOCIATED WITH THE UPPER LOW
WORKS ACROSS. COOLING THERMAL FIELDS WILL ALSO ALLOW MOISTURE TO
BECOME BETTER PLACED WITHIN THE DENDRITIC GROWTH ZONE. WEST TO WEST-
NORTHWEST WINDS WILL FAVOR THE SOUTHERN PORTION OF THE FORECAST AREA
FOR LAKE ENHANCED SNOW SHOWERS LATE TONIGHT AND SUNDAY. WITH
PRECIPITATION OCCURRING IN BANDS...ACCUMULATIONS WILL BE HIGHLY
VARIABLE (MAYBE UP TO AN INCH)...AND RAPID FLUCTUATIONS IN VISIBILITY
ARE POSSIBLE UNTIL LATE AFTERNOON WHEN DRIER AIR SHOULD AGAIN WORK
INTO THE SOUTHERN CENTRAL PORTIONS OF THE FORECAST AREA. SURFACE
TROUGH WILL DEEPEN OVER LAKE HURON TONIGHT AND SUNDAY AS THE UPPER
LOW APPROACHES...EVENTUALLY RESULTING IN A COLD FRONT DROPPING SOUTH
INTO THE SOUTH-CENTRAL LOWER MICHIGAN LATE SUNDAY...AND INTO THE
REST OF THE AREA SUNDAY NIGHT. THIS WILL AGAIN BRING CHANCES FOR
SNOW SHOWERS.
MAIN STORY WILL REALLY BE THE ARRIVAL OF MUCH COLDER TEMPERATURES.
THE COLD AIR WILL ALSO COMBINE WITH GUSTY WINDS THROUGH MUCH OF THE
WEEKEND TO PRODUCE SOME OF THE COLDEST WIND CHILLS SO FAR THIS
WINTER. TEMPS FALLING INTO THE TEENS TONIGHT WILL RECOVER LITTLE ON
SUNDAY AS ARCTIC AIRMASS CONTINUES TO SPILL IN. GUSTY WINDS WILL
KEEP WIND CHILLS BELOW ZERO FOR MUCH OF THE AREA BOTH TOMORROW AND
MONDAY (LOW SINGLE DIGITS FOR DETROIT). SINGLE DIGIT LOWS ARE THEN
EXPECTED BOTH SUNDAY AND MONDAY NIGHTS...PRODUCING WIND CHILLS IN
THE -10 TO -15F DEGREE RANGE SUNDAY NIGHT.
TUESDAY THROUGH SUNDAY.
A COUPLE OF WEAK WEATHER SYSTEMS ARE EXPECTED TO MOVE ACROSS
SOUTHEAST MICHIGAN BEGINNING MIDWEEK. THESE SYSTEMS WILL BRING IN
CHANCES FOR FLURRIES AND LIGHT SNOW SHOWERS THROUGH FRIDAY EVENING.
LITTLE TO NO ACCUMULATION IS CURRENTLY ANTICIPATED WITH THESE
SHOWERS. TEMPERATURES WILL GRADUALLY WARM BACK TOWARD THE SEASONAL
NORM BY THE END OF THE FORECAST PERIOD.
MARINE...
AN ARCTIC COLD FRONT WILL MOVE THROUGH THE SOUTHERN GREAT LAKES
TONIGHT AND LEAVE A LOW/SURFACE TROUGH STALLED OVER LAKE SUPERIOR
AND NORTHERN LAKE HURON. THIS WILL KEEP THE STRONGEST WIND FOCUSED
FROM THE SOUTH HALF OF LAKE HURON THROUGH WESTERN LAKE ERIE SUNDAY
AND MONDAY. THE WESTERLY FLOW OVER THE SHORT FETCH OF SOUTHERN LAKE
HURON OPEN WATER FAVORS GUSTS MOSTLY BELOW GALES AND GUSTS AROUND 25
KNOTS OR LESS OVER LAKE ST CLAIR AND THE MICHIGAN WATERS OF LAKE
ERIE. WHILE HEADLINES FOR WIND ARE NOT YET NEEDED...THE ARCTIC AIR
SPILLING OVER THE REGION WILL MAKE FREEZING SPRAY AND ICING A
CONCERN IN THE FORECAST. THE BEST COMBINATION OF WIND...WATER
TEMPERATURE...AND AIR TEMPERATURE ARE ONLY SUPPORTING MODERATE
FREEZING SPRAY IN WESTERLY FLOW OVER U.S. WATERS OVER THE SOUTH HALF
OF LAKE HURON. THIS WILL BE MONITORED ALSO WITHOUT A HEADLINE FOR
NOW.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......RBP
AVIATION.....RBP
DISCUSSION...HLO/DE
MARINE.......BT
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
619 PM EST SAT JAN 16 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 434 PM EST SAT JAN 16 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A COLD MID/UPPER LEVEL LOW
JUST NE OF WINNIPEG. AT THE SFC...WINDS WERE BACKING AHEAD OF THE
LOW WHICH HAS PUSHED THE HEAVIER LES BAND IN ERN LAKE SUPERIOR TO
THE E MUNSING. LAKE INDUCED TROUGHING EXTENDED FROM SRN INTO W CNTRL
LAKE SUPERIOR RESULTING IN THE STRONGEST LOW LEVEL CONV INTO THE
KEWEENAW NEAR HOUGHTON WHERE A VERY HEAVY LES BAND HAS PRODUCED
HIGHER SNOWFALL RATES OF A FEW INCHES PER HOUR.
TONIGHT...DEEP COLD AIR WILL CONTINUE TO SETTLE OVER THE REGION
TONIGHT WITH 850 MB TEMPS INTO THE -21C TO -25C RANGE AND 700 MB
TEMPS TO AROUND -30C. THE VERY STRONG INSTABILITY WITH LAKE INDUCED
CAPE TO 1K J/KG AND EQUILLIBRIUM HEIGHTS TO 14K FT WILL CONTINUE TO
SUPPORT THE DEVELOPMENT OF INTENSE LES BANDS. THE STRONG CONVECTION
OVER THE LAKE WILL ALSO HELP TO KEEP THE DGZ IN THE CONVECTIVE LAYER
WITH FLUFFY SNOW SLR VALUES TO AT LEAST 25/1.
AS THE MID LEVEL LOW MOVES INTO LAKE SUPERIOR...THE MODELS SUGGEST
THAT THE TROUGH TO NEAR CMX WILL GRADUALLY SINK TO THE SOUTH.
SO...ALTHOUGH HIGHER SNOWFALL RATES WILL CONTINUE...THE HEAVIER
BANDS ARE NOT EXPECTED TO REMAIN IN PLACE FOR AN EXTENDED PERIOD.
HOWEVER...ADDITIONAL SNOW AMOUNTS OF 4 TO 8 INCHES ARE EXPECTED
TONIGHT...HEAVIEST FROM CMX TO MASS CITY AND THE PORCUPINES.
OVER THE EAST...THE HEAVIEST SNOW THIS EVENING IS EXPECTED NEAR
LAKE SUPERIOR CLOSER TO PICTURED ROCKS AND GRAND MARAIS. THE HIGH
RES MODELS HAVE BEEN CONSISTENT IN SHOWING A SHARP TROUGH OR MESO LOW
DEVELOPING OVER S CNTRL LAKE SUPERIOR AND SLIDING INTO ALGER COUNTY.
STRONG LOW LEVEL CONV ASSOCIATED ON THE WRN EDGE OF THIS FEATURE WILL
BRING HEAVY LES INTO MAINLY ALGER COUNTY BTWN 06Z-12Z WITH CONTINUED
HEAVIER NNW TO NW FLOW LES BANDS SUN MORNING. THERE IS MORE
UNCERTAINTY ON HOW FAR WEST THE BAND WILL MOVE. LAND BREEZE
DEVELOPMENT SHOULD BE STRONG ENOUGH TO KEEP THE STRONGEST LES EAST OF
MARQUETTE WITH ONLY SOME LIGHTER BANDS ON THE EDGE OF THE LOW FARTHER
TO THE WEST. THE QUICK BURST OF SNOW COULD RESULT IN SNOWFALL RATES
OF 1 TO 3 INCHES PER HOUR FOR A FEW HOURS...ESPECIALY OVER WRN ALGER
COUNTY.
THE VERY COLD AIR MOVING INTO INTERIOR LOCATIONS WILL DROP WIND
CHILLS INTO THE -20 TO -30 RANGE NEAR THE WI BORDER FROM IRONWOOD TO
CRYSTAL FALLS WHERE A WIND CHILL ADVY WAS ISSUED. EXPECT ENOUGH LAKE
MODERATION FARTHER NORTH FOR WIND CHILLS MAINLY IN THE -10 TO -20
RANGE.
SUNDAY...AFTER THE BURST OF HEAVIER SNOW IN THE MORNING OVER MAINLY
WRN ALGER COUNTY...THE LES IS EXPECTED TO EVOLVE INTO LIGHT TO
MODERATE MULTIPLE WIND PARALLEL BANDS WITH A FEW HEAVIER EMBEDDED
BANDS. WHILE MORNING SNOW TOTALS COULD REACH 6 INCHES...AFTERNOON
AMOUNTS SHOULD MAINLY BE IN THE 2 TO 4 INCH RANGE.
OVER THE WEST....A SHORTER FETCH AND LESS FAVORABLE LOW LEVEL CONV
WITH THE SLOWLY BACKING NW FLOW WILL KEEP AMOUNTS IN THE 2 TO 5 INCH
RANGE. IN ADDITION...THE DGZ FALLING CLOSER TO THE LAKE SFC WILL
INHIBIT SNOW GROWTH WITH MAINLY SMALLER FLAKES THAT CAN LEAD TO LOW
VSBY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 409 PM EST SAT JAN 16 2016
MAIN ATTENTION IS ON HEALTHY LES SUN NIGHT AND MON THAT WILL
DIMINISH MON NIGHT AND TUE.
THE UPPER LOW THAT IS BRINGING THIS MASS OF COLD AIR WILL JUST E OF
THE CWA AT 00Z MON...850MB TEMPS WILL BE AROUND -23C TO START SUN
NIGHT. MODERATE TO HEAVY LES WILL BE ONGOING IN THE NW WIND
SNOWBELTS AT 00Z MON...ESPECIALLY IN AREAS E OF MARQUETTE COUNTY.
SHOULD SEE OVERALL STEADY LES SUN NIGHT INTO MUCH OF MON...WITH
DIMINISHING STARTING IN THE AFTERNOON W AND IN THE EVENING E AS THE
UPPER LOW MOVES AWAY...850MB TEMPS WARM BY 4-5 DEGREES AND WARMER
AND DRIER AIR MOVES IN ABOVE THE MOIST LAKE INFLUENCED LAYER. LAKE
INDUCED EQUILIBRIUM LEVELS SHOULD RANGE FROM 10KFT AT CMX TO 15KFT
AT GRAND MARAIS AT 00Z SUN...LOWERING BY AROUND 3KFT BY 12Z
SUN...THEN GRADUALLY DROPPING TO AROUND 6KFT OVER MOST OF THE LAKE
BY 00Z TUE. A SHORTWAVE DROPPING ACROSS LAKE SUPERIOR MON AFTERNOON
SHOULD HELP OFFSET SOME OF THE AFOREMENTIONED INCREASINGLY
UNFAVORABLE FEATURES. BETWEEN 00Z MON AND 00Z TUE...EXPECT ANOTHER 3-
5 INCHES OVER NW UPPER MI AND 6-10 INCHES OVER THE NW WIND FAVORED
AREAS OF ERN UPPER MI (MAINLY E OF MARQUETTE COUNTY). EXPECT WINDS
TO INCREASE SUN NIGHT INTO MON...WITH GUSTS UP TO 35MPH ALONG THE
SHORELINES E OF MARQUETTE AND 25-30MPH ELSEWHERE NEAR LAKE SUPERIOR.
THIS WILL PRODUCE QUITE A BIT OF BLOWING SNOW...ESPECIALLY ALONG M-
28 E OF HARVEY (NOT AS MUCH AS IF THERE WAS SIGNIFICANT ICE COVER ON
LAKE SUPERIOR AS IN YEARS PAST). MON NIGHT WILL SEE MODERATE SNOW
POTENTIAL EARLY...BUT INVERSIONS WILL BE LOWERING AND 850MB TEMPS
INCREASING TO AROUND -14C AS A SFC RIDGE MOVES TO W OF LAKE
SUPERIOR. LES WILL CONTINUE TO DIMINISH ON TUE...WITH ONLY LIGHT LES
EXPECTED...BUT WILL NOT COMPLETELY END.
SUN NIGHT AND MON MORNING WILL ALSO BE QUITE COLD WITH LOWS IN THE
SINGLE DIGITS ABOVE AND BELOW ZERO IN MOST PLACES...AROUND -10 ALONG
THE WI BORDER IN GOGEBIC COUNTY. RESULTING WIND CHILL VALUES WILL
FALL BELOW -15 OVER MUCH OF THE CENTRAL AND W...DOWN TO -25 TO -30
IN THE COLDEST SPOTS.
AFTER TUE WE COULD SEE A COUPLE SHORTWAVES MOVES THROUGH BEFORE
THU...WHICH MAY OR MAY NOT PRODUCE ANY WIDESPREAD LIGHT SNOW. THERE
IS ENOUGH UNCERTAINTY AND LACK OF SIGNIFICANT CONDITIONS AFTER TUE
TO JUST RUN WITH A CONSENSUS BLEND FOR THE FORECAST.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 618 PM EST SAT JAN 16 2016
AT KIWD/KCMX...NW FLOW LAKE EFFECT CONTINUES THROUGH THE WEEKEND.
EXPECT IFR VSBY DURING THE HEAVIER SNOW BANDS AT IWD BUT MAINLY IFR
VSBY AT CMX...BUT THIS WILL BE A VARIABLE CONDITION.
AT KSAW...MVFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE FORECAST
PERIOD WITH THE LAKE EFFECT SNOW SHOWERS STAYING MOSTLY TO THE EAST.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 434 PM EST SAT JAN 16 2016
A LOW MOVING FROM SOUTHERN ONTARIO TO QUEBEC WILL BRING COLDER AIR
ACROSS LK SUPERIOR THROUGH THE WEEKEND. BEHIND THE LOW...A TROUGH
WILL REMAIN FAIRLY STATIONARY OVER SOUTHERN LAKE SUPERIOR INTO
TUESDAY...KEEPING WIND GUSTS BETWEEN 25-30KTS. IN ADDITION...THERE
IS THE POTENTIAL FOR HEAVY FREEZING SPRAY SUNDAY INTO MONDAY. WINDS
ARE EXPECTED TO SLOWLY DIMINISH TOWARDS THE MIDDLE OF NEXT WEEK...AS
HIGH PRESSURE MOVES OVER THE UPPER GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST SUNDAY FOR MIZ002-003.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST SUNDAY FOR MIZ001-084.
WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO NOON CST MONDAY
FOR MIZ009-010.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ007-085.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST MONDAY FOR MIZ006.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 AM SUNDAY TO 1 PM EST MONDAY
FOR LSZ264>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS GAYLORD MI
121 PM EST FRI JAN 15 2016
.UPDATE...
ISSUED AT 949 AM EST FRI JAN 15 2016
AREAS FROM GAYLORD NORTH AND HIGHER TERRAIN WILL CONTINUE TO SEE
FZDZ THROUGH MIDDAY. 12Z KAPX SOUNDING SHOWED CLASSIC FREEZING
DRIZZLE PROFILE WITH MID LEVEL DRYING/SATURATED LAYER ABOVE -5C
AND BELOW 0C. SFC LOW NORTH OF MKX WILL MOVE EAST TODAY ACROSS THE
REGION PULLING A COLD FRONT THROUGH LATER TODAY. AS THE LOW PUSHES
THROUGH THE REGION EXPECT SATURATED LAYER TO INCREASE LEADING TO
MORE RAIN/SNOW INSTEAD OF FREEZING DRIZZLE. TEMPERATURES SHOULD
GET TO ABOVE/AROUND 32F TODAY ACROSS NORTHERN LOWER WITH MAINLY
20S ACROSS EASTERN UPPER WITH A COUPLE INCHES OF SNOW POSSIBLE
NORTH BY EVENING.
&&
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 306 AM EST FRI JAN 15 2016
SURFACE LOW CENTER HAS REACHED SRN WISCONSIN EARLY THIS MORNING...
WITH THE ASSOCIATED WARM FRONT EXTENDING EASTWARD FROM THE LOW
CENTER THRU SRN LWR MICHIGAN. MODELS CONTINUE TO OVER-FORECAST
PRECIP ALONG AND NORTH OF THIS WARM FRONT. LATEST LOOK AT KAPX SHOWS
ONLY PATCHY LIGHT FREEZING DRIZZLE AND/OR FLURRIES LINGERING ACROSS
MANLY THE NRN HALF OF OUR CWA IN THE WAKE OF AN AREA OF LIGHT SNOW
THAT HAS PUSHED NORTH OF OUR CWA. A VERY LIGHT MIST/FREEZING DRIZZLE
IS FALLING HERE AT THE GAYLORD OFFICE...WHICH MAKES SENSE LOOKING AT
OUR MODEL SOUNDINGS FOR EARLY THIS MORNING. LOW LEVELS ARE SATURATED
THRU ABOUT 850 MB...WITH A THICK LAYER OF DRY AIR AT MID LEVELS...
AND THEN ADDITIONAL MOISTURE ABOVE 600 MB. LOW LEVEL MOISTURE COMES
NOWHERE NEAR THE -10 C ISOTHERM AND SURFACE TEMPS REMAIN WELL BELOW
FREEZING AT THIS HOUR...THUS THE PATCHY LIGHT FREEZING DRIZZLE.
BOTH THE LATEST RAP13 AND THE HRRR SHOW ONLY SMALL CHANCES OF LIGHT
PRECIP EARLY THIS MORNING ACROSS MOST OF OUR CWA THRU DAYBREAK...
WITH SOME INDICATION OF GRADUALLY INCREASING POPS AS WE HEAD THRU
THE DAY IN RESPONSE TO INCREASING LIFT AND MOISTURE NEAR THE SURFACE
LOW CENTER. HIGHEST POPS ACTUALLY DEVELOP ACROSS THE SE HALF OF OUR
CWA THIS AFTERNOON JUST AHEAD OF THE SURFACE LOW CENTER AS IT TRACKS
NE THRU NRN LWR MICHIGAN. MODEL SOUNDINGS STILL SUGGEST A RATHER
TIGHT LOW LEVEL THERMAL GRADIENT WILL SET UP ACROSS OUR SRN CWA
TODAY AS THE LOW TRACKS RIGHT OVERHEAD. BASED ON MODEL SOUNDINGS...
PRECIP SHOULD REMAIN ALL SNOW ACROSS ERN UPR MICHIGAN AND THE TIP OF
THE MITT...WITH A MIX OF RAIN/SNOW AND POSSIBLY SOME FREEZING RAIN
AND SLEET MIXING IN AT TIMES ALONG THE TIGHT TEMP GRADIENT. PRECIP
WILL LIKELY BECOME ALL RAIN FOR PORTIONS OF OUR SRN CWA AND
ESPECIALLY OUR SE CWA FROM ROGERS CITY TO HOUGHTON LAKE EASTWARD AS
THE WARMEST AIR SURGES NORTHWARD IN THE AFTERNOON WITHIN THIS AREA
JUST AHEAD OF THE SURFACE LOW CENTER. WITH HIGH TEMPS WARMING INTO
THE MID TO UPPER 30S ACROSS MOST OF NRN LWR MICHIGAN...DO NOT EXPECT
ANY SIGNIFICANT ICE ACCUMULATION...BUT WILL CERTAINLY KEEP A CLOSE
EYE ON PRECIP TYPE AND DURATION AS THIS EVENT UNFOLDS. PRIMARY
CHANGES TO THE FORECAST WILL BE TO DECREASE POPS...ESPECIALLY THIS
MORNING BASED ON NEAR TERM OBSERVED AND MODEL TRENDS. CAA KICKS IN
IN THE WAKE OF THE DEPARTING LOW TONIGHT...SWITCHING PRECIP TYPE
BACK OVER TO ALL SNOW. ALSO...OVER-LAKE INSTABILITY WILL AGAIN
INCREASE WITH ONGOING CAA...TARGETING NW FLOW AREAS FOR HIGHEST POPS
TONIGHT. NEW SNOW ACCUMULATIONS WILL BE A GENERAL 1 TO 3 INCHES
TODAY FOR OUR NRN CWA...WITH ANOTHER INCH OR SO TONIGHT.
&&
.SHORT TERM...(SATURDAY THROUGH SUNDAY NIGHT)
ISSUED AT 306 AM EST FRI JAN 15 2016
SATURDAY AND SUNDAY...COLD AND SNOWY WEATHER TO CONTINUE ACROSS THE
GREAT LAKES REGION THIS WEEKEND. A STORM SYSTEM OVER THE EASTERN
LAKES SATURDAY WILL EXIT NORTHEAST INTO QUEBEC SUNDAY...WHILE AN
UPPER LVL SYSTEM SETTLES INTO THE REGION. MODEL SOUNDINGS AND MSTR
PROGS SHOW MID LVL DRYING (700/500MB RH UNDER 50 PCT) SATURDAY
AFTERNOON AS THE SFC LOW LIFTS NORTHEAST INTO QUEBEC...DIMINISHING
SNOWFALL ACROSS NORTHEAST LOWER SATURDAY AFTERNOON AND EVENING.
HOWEVER LAKE EFFECT PARAMETERS WILL STRENGTHEN SATURDAY AFTERNOON
ACRS THE WRN LAKES...WITH 850MB TEMPS FALLING TO -16C WHILE LOW LVL
INVERSION HEIGHTS INCREASE TO 4K FEET. SFC-850MB WINDS WILL
TRANSITION FROM NORTHWEST TO WEST THROUGH SATURDAY AFTERNOON IN
DIMINISHING CYCLONIC FLOW ON THE BACKSIDE OF THE EXITING STORM
SYSTEM. OVERALL WILL DIMINISH POPS ACROSS NORTHEAST LOWER SATURDAY
MORNING AS DRY MID LVL AIR SETTLES OVER THE REGION...WITH AT LEAST
LIKELY POPS OVER THE WRN LAKES THROUGH SATURDAY EVENING DUE TO LAKE
EFFECTS
SIGNIFICANT SNOW IS POSSIBLE SUNDAY FOR PORTIONS OF NRN MI...THE
COMBINATION OF AN UPPER LOW DROPPING INTO THE GREAT LAKES AS MID LVL
MSTR INCREASES AND LAKE EFFECT PARAMETERS STRENGTHEN. 700/500MB RH
INCREASES TO GREATER THAN 90 PCT SUNDAY WHILE 850/500MB QVECTOR
CONVERGENCE SHOWS STRONG FORCING OVER NRN MI IN ADVANCE OF
APPROACHING UPPER LOW. MODEL SOUNDINGS CONTINUE TO SHOW LAKE
PARAMETERS IMPROVING THROUGH THE DAY SUNDAY AS 850MB TEMPS DROP TO
-24C...INVERSION HEIGHTS INCREASE TO NEARLY 9KT WITH ABUNDANCE MSTR
THROUGH THE COLUMN. LAKES BANDS WILL BE HIGHLY UNORGANIZED THROUGH
18Z SUNDAY AS SFC-850MB WINDS SHIFT FROM SOUTHWEST TO WEST BEFORE
FINALLY LOCKING IN NORTHWEST SUNDAY EVENING INTO MONDAY. OVERALL
WILL MENTION SNOW FOR THE ENTIRE CWA SUNDAY WITH LAKE ENHANCEMENTS
FORCING HIGHEST POPS OVER THE WRN LAKES.
HIGH TEMPERATURES THIS WEEKEND WILL FALL FROM NEAR SEASONAL READINGS
IN THE 20S SATURDAY TO BETWEEN 10 AND 15 DEGREES SUNDAY AS 850MB
TEMPS PLUNGE TO -24C IN DEEPENING UPPER TROUGH.
&&
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 306 AM EST FRI JAN 15 2016
MONDAY THROUGH THURSDAY...SURFACE AND UPPER LVL STORM SYSTEMS WILL
BE IN PLACE OVER THE GREAT LAKES TO BEGIN THE UPCOMING WORK
WEEK...BEFORE SLOWLY EXITING EAST OF THE REGION TUESDAY. THIS
PATTERN WILL GENERATE SNOW ACROSS MUCH OF NORTHERN MICHIGAN MONDAY
WITH LAKE EFFECT SNOW OVER THE WRN LAKES TUESDAY...DUE TO LINGERING
CYCLONIC FLOW ON THE BACK SIDE OF THE EXITING STORM SYSTEM (NW WINDS
SFC-850MB WITH INVERSION HEIGHTS TO 6K FT). TEMPERATURES WILL BE
BELOW NORMAL THROUGH TUESDAY AS 850MB TEMPS IN THE BASE OF THE 500MB
TROUGH DROP TO -24C...FORCING DAYTIME HIGHS TO REMAIN IN THE TEENS
WITH LOWS IN THE SINGLE DIGITS.
WEDNESDAY AND THURSDAY ARE CURRENTLY TRENDING LESS ACTIVE WHEN
COMPARED TO THE PAST WEEK. A LARGE AREA OF HIGH PRESSURE AND DRY AIR
WILL SETTLE OVER THE ENTIRE GREAT LAKES AND OHIO VALLEY BY MID
WEEK...WHILE 500MB HEIGHTS INCREASE ACROSS THE UPPER MIDWEST. ANY
LAKE INFLUENCES WEDNESDAY AND THURSDAY WILL BE HINDERED BY LACK OF
OVER WATER INSTABILITY WITH 850MB TEMPS WARMING TO -8C THURSDAY. THE
WARMING IN MID LVLS WILL HELP DAYTIME TEMPS TREND CLOSER TO MID
JANUARY SEASONAL LEVELS IN THE LOWER 20S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 114 PM EST FRI JAN 15 2016
WARM FRONT HAS PASSED THRU KMDL/KTVC BRIEFLY IMPROVING
CONDITIONS. KAPN/KPLN WILL REMAIN IN IFR CONDITIONS FOR SEVERAL
MORE HOURS. AREA OF RAINFALL MOVING NORTHEAST WILL CLIP APN BTWN
18Z AND 22Z.
SFC LOW AND COLD FRONT WILL MOVE THROUGH REGION FROM AROUND 21Z
TVC/MBL TO APPROX 02Z AT APN. SNOW SHOWERS WILL KICK IN AFTER COLD
FRONT PASSAGE AND LAKE EFFECT STARTS UP AT TVC/MBL TOWARD MORNING.
&&
.MARINE...
ISSUED AT 306 AM EST FRI JAN 15 2016
WINDS AND WAVES WILL REMAIN JUST AT SCA CRITERIA THRU MUCH OF TODAY
FOR OUR NRN NEARSHORE AREAS JUST NORTH OF THE SURFACE LOW CENTER
TRACK. MAINLY SNOW IS EXPECTED WITHIN THESE AREAS...WITH A WINTRY
MIX OF PRECIP EXPECTED FOR OUR NEARSHORE AREAS SOUTH OF THE ADVISORY
AREAS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...FARINA
NEAR TERM...MLR
SHORT TERM...SWR
LONG TERM...SWR
AVIATION...FARINA
MARINE...MLR
AREA FORECAST DISCUSSION
NWS GAYLORD MI
955 AM EST FRI JAN 15 2016
.UPDATE...
ISSUED AT 949 AM EST FRI JAN 15 2016
AREAS FROM GAYLORD NORTH AND HIGHER TERRAIN WILL CONTINUE TO SEE
FZDZ THROUGH MIDDAY. 12Z KAPX SOUNDING SHOWED CLASSIC FREEZING
DRIZZLE PROFILE WITH MID LEVEL DRYING/SATURATED LAYER ABOVE -5C
AND BELOW 0C. SFC LOW NORTH OF MKX WILL MOVE EAST TODAY ACROSS THE
REGION PULLING A COLD FRONT THROUGH LATER TODAY. AS THE LOW PUSHES
THROUGH THE REGION EXPECT SATURATED LAYER TO INCREASE LEADING TO
MORE RAIN/SNOW INSTEAD OF FREEZING DRIZZLE. TEMPERATURES SHOULD
GET TO ABOVE/AROUND 32F TODAY ACROSS NORTHERN LOWER WITH MAINLY
20S ACROSS EASTERN UPPER WITH A COUPLE INCHES OF SNOW POSSIBLE
NORTH BY EVENING.
&&
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 306 AM EST FRI JAN 15 2016
SURFACE LOW CENTER HAS REACHED SRN WISCONSIN EARLY THIS MORNING...
WITH THE ASSOCIATED WARM FRONT EXTENDING EASTWARD FROM THE LOW
CENTER THRU SRN LWR MICHIGAN. MODELS CONTINUE TO OVER-FORECAST
PRECIP ALONG AND NORTH OF THIS WARM FRONT. LATEST LOOK AT KAPX SHOWS
ONLY PATCHY LIGHT FREEZING DRIZZLE AND/OR FLURRIES LINGERING ACROSS
MANLY THE NRN HALF OF OUR CWA IN THE WAKE OF AN AREA OF LIGHT SNOW
THAT HAS PUSHED NORTH OF OUR CWA. A VERY LIGHT MIST/FREEZING DRIZZLE
IS FALLING HERE AT THE GAYLORD OFFICE...WHICH MAKES SENSE LOOKING AT
OUR MODEL SOUNDINGS FOR EARLY THIS MORNING. LOW LEVELS ARE SATURATED
THRU ABOUT 850 MB...WITH A THICK LAYER OF DRY AIR AT MID LEVELS...
AND THEN ADDITIONAL MOISTURE ABOVE 600 MB. LOW LEVEL MOISTURE COMES
NOWHERE NEAR THE -10 C ISOTHERM AND SURFACE TEMPS REMAIN WELL BELOW
FREEZING AT THIS HOUR...THUS THE PATCHY LIGHT FREEZING DRIZZLE.
BOTH THE LATEST RAP13 AND THE HRRR SHOW ONLY SMALL CHANCES OF LIGHT
PRECIP EARLY THIS MORNING ACROSS MOST OF OUR CWA THRU DAYBREAK...
WITH SOME INDICATION OF GRADUALLY INCREASING POPS AS WE HEAD THRU
THE DAY IN RESPONSE TO INCREASING LIFT AND MOISTURE NEAR THE SURFACE
LOW CENTER. HIGHEST POPS ACTUALLY DEVELOP ACROSS THE SE HALF OF OUR
CWA THIS AFTERNOON JUST AHEAD OF THE SURFACE LOW CENTER AS IT TRACKS
NE THRU NRN LWR MICHIGAN. MODEL SOUNDINGS STILL SUGGEST A RATHER
TIGHT LOW LEVEL THERMAL GRADIENT WILL SET UP ACROSS OUR SRN CWA
TODAY AS THE LOW TRACKS RIGHT OVERHEAD. BASED ON MODEL SOUNDINGS...
PRECIP SHOULD REMAIN ALL SNOW ACROSS ERN UPR MICHIGAN AND THE TIP OF
THE MITT...WITH A MIX OF RAIN/SNOW AND POSSIBLY SOME FREEZING RAIN
AND SLEET MIXING IN AT TIMES ALONG THE TIGHT TEMP GRADIENT. PRECIP
WILL LIKELY BECOME ALL RAIN FOR PORTIONS OF OUR SRN CWA AND
ESPECIALLY OUR SE CWA FROM ROGERS CITY TO HOUGHTON LAKE EASTWARD AS
THE WARMEST AIR SURGES NORTHWARD IN THE AFTERNOON WITHIN THIS AREA
JUST AHEAD OF THE SURFACE LOW CENTER. WITH HIGH TEMPS WARMING INTO
THE MID TO UPPER 30S ACROSS MOST OF NRN LWR MICHIGAN...DO NOT EXPECT
ANY SIGNIFICANT ICE ACCUMULATION...BUT WILL CERTAINLY KEEP A CLOSE
EYE ON PRECIP TYPE AND DURATION AS THIS EVENT UNFOLDS. PRIMARY
CHANGES TO THE FORECAST WILL BE TO DECREASE POPS...ESPECIALLY THIS
MORNING BASED ON NEAR TERM OBSERVED AND MODEL TRENDS. CAA KICKS IN
IN THE WAKE OF THE DEPARTING LOW TONIGHT...SWITCHING PRECIP TYPE
BACK OVER TO ALL SNOW. ALSO...OVER-LAKE INSTABILITY WILL AGAIN
INCREASE WITH ONGOING CAA...TARGETING NW FLOW AREAS FOR HIGHEST POPS
TONIGHT. NEW SNOW ACCUMULATIONS WILL BE A GENERAL 1 TO 3 INCHES
TODAY FOR OUR NRN CWA...WITH ANOTHER INCH OR SO TONIGHT.
&&
.SHORT TERM...(SATURDAY THROUGH SUNDAY NIGHT)
ISSUED AT 306 AM EST FRI JAN 15 2016
SATURDAY AND SUNDAY...COLD AND SNOWY WEATHER TO CONTINUE ACROSS THE
GREAT LAKES REGION THIS WEEKEND. A STORM SYSTEM OVER THE EASTERN
LAKES SATURDAY WILL EXIT NORTHEAST INTO QUEBEC SUNDAY...WHILE AN
UPPER LVL SYSTEM SETTLES INTO THE REGION. MODEL SOUNDINGS AND MSTR
PROGS SHOW MID LVL DRYING (700/500MB RH UNDER 50 PCT) SATURDAY
AFTERNOON AS THE SFC LOW LIFTS NORTHEAST INTO QUEBEC...DIMINISHING
SNOWFALL ACROSS NORTHEAST LOWER SATURDAY AFTERNOON AND EVENING.
HOWEVER LAKE EFFECT PARAMETERS WILL STRENGTHEN SATURDAY AFTERNOON
ACRS THE WRN LAKES...WITH 850MB TEMPS FALLING TO -16C WHILE LOW LVL
INVERSION HEIGHTS INCREASE TO 4K FEET. SFC-850MB WINDS WILL
TRANSITION FROM NORTHWEST TO WEST THROUGH SATURDAY AFTERNOON IN
DIMINISHING CYCLONIC FLOW ON THE BACKSIDE OF THE EXITING STORM
SYSTEM. OVERALL WILL DIMINISH POPS ACROSS NORTHEAST LOWER SATURDAY
MORNING AS DRY MID LVL AIR SETTLES OVER THE REGION...WITH AT LEAST
LIKELY POPS OVER THE WRN LAKES THROUGH SATURDAY EVENING DUE TO LAKE
EFFECTS
SIGNIFICANT SNOW IS POSSIBLE SUNDAY FOR PORTIONS OF NRN MI...THE
COMBINATION OF AN UPPER LOW DROPPING INTO THE GREAT LAKES AS MID LVL
MSTR INCREASES AND LAKE EFFECT PARAMETERS STRENGTHEN. 700/500MB RH
INCREASES TO GREATER THAN 90 PCT SUNDAY WHILE 850/500MB QVECTOR
CONVERGENCE SHOWS STRONG FORCING OVER NRN MI IN ADVANCE OF
APPROACHING UPPER LOW. MODEL SOUNDINGS CONTINUE TO SHOW LAKE
PARAMETERS IMPROVING THROUGH THE DAY SUNDAY AS 850MB TEMPS DROP TO
-24C...INVERSION HEIGHTS INCREASE TO NEARLY 9KT WITH ABUNDANCE MSTR
THROUGH THE COLUMN. LAKES BANDS WILL BE HIGHLY UNORGANIZED THROUGH
18Z SUNDAY AS SFC-850MB WINDS SHIFT FROM SOUTHWEST TO WEST BEFORE
FINALLY LOCKING IN NORTHWEST SUNDAY EVENING INTO MONDAY. OVERALL
WILL MENTION SNOW FOR THE ENTIRE CWA SUNDAY WITH LAKE ENHANCEMENTS
FORCING HIGHEST POPS OVER THE WRN LAKES.
HIGH TEMPERATURES THIS WEEKEND WILL FALL FROM NEAR SEASONAL READINGS
IN THE 20S SATURDAY TO BETWEEN 10 AND 15 DEGREES SUNDAY AS 850MB
TEMPS PLUNGE TO -24C IN DEEPENING UPPER TROUGH.
&&
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 306 AM EST FRI JAN 15 2016
MONDAY THROUGH THURSDAY...SURFACE AND UPPER LVL STORM SYSTEMS WILL
BE IN PLACE OVER THE GREAT LAKES TO BEGIN THE UPCOMING WORK
WEEK...BEFORE SLOWLY EXITING EAST OF THE REGION TUESDAY. THIS
PATTERN WILL GENERATE SNOW ACROSS MUCH OF NORTHERN MICHIGAN MONDAY
WITH LAKE EFFECT SNOW OVER THE WRN LAKES TUESDAY...DUE TO LINGERING
CYCLONIC FLOW ON THE BACK SIDE OF THE EXITING STORM SYSTEM (NW WINDS
SFC-850MB WITH INVERSION HEIGHTS TO 6K FT). TEMPERATURES WILL BE
BELOW NORMAL THROUGH TUESDAY AS 850MB TEMPS IN THE BASE OF THE 500MB
TROUGH DROP TO -24C...FORCING DAYTIME HIGHS TO REMAIN IN THE TEENS
WITH LOWS IN THE SINGLE DIGITS.
WEDNESDAY AND THURSDAY ARE CURRENTLY TRENDING LESS ACTIVE WHEN
COMPARED TO THE PAST WEEK. A LARGE AREA OF HIGH PRESSURE AND DRY AIR
WILL SETTLE OVER THE ENTIRE GREAT LAKES AND OHIO VALLEY BY MID
WEEK...WHILE 500MB HEIGHTS INCREASE ACROSS THE UPPER MIDWEST. ANY
LAKE INFLUENCES WEDNESDAY AND THURSDAY WILL BE HINDERED BY LACK OF
OVER WATER INSTABILITY WITH 850MB TEMPS WARMING TO -8C THURSDAY. THE
WARMING IN MID LVLS WILL HELP DAYTIME TEMPS TREND CLOSER TO MID
JANUARY SEASONAL LEVELS IN THE LOWER 20S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 600 AM EST FRI JAN 15 2016
PATCHY FREEZING DRIZZLE WILL CONTINUE TO IMPACT NRN LWR MICHIGAN
THIS MORNING BEFORE BETTER CHANCES OF MEASURABLE PRECIP DEVELOPS
THIS AFTERNOON AND TONIGHT. A MIX OF RAIN AND/OR SNOW IS POSSIBLE
THIS AFTERNOON AHEAD OF LOW PRESSURE TRACKING DIRECTLY OVER NRN
LWR MICHIGAN. THE BEST CHANCE OF MIXED PRECIP WILL BE AROUND
APN...TVC AND MBL. PLN WILL LIKELY REMAIN ALL SNOW JUST NORTH OF
THE TRACK OF THE SURFACE LOW. OVERALL PRECIP INTENSITY WILL REMAIN
LIGHT ACROSS THE ENTIRE REGION. ALL PRECIP WILL AGAIN BECOME ALL
SNOW BY LATE EVENING AS CAA COMMENCES IN THE WAKE OF THE DEPARTING
LOW. CONDITIONS WILL REMAIN IFR TO LOW MVFR THRU THE ENTIRE TAF
FORECAST PERIOD. EAST WIND AROUND 10 KTS TODAY WILL SHIFT TO THE
N/NW BEHIND THE LOW TONIGHT WITH GUSTS TO 20 KTS EXPECTED.
&&
.MARINE...
ISSUED AT 306 AM EST FRI JAN 15 2016
WINDS AND WAVES WILL REMAIN JUST AT SCA CRITERIA THRU MUCH OF TODAY
FOR OUR NRN NEARSHORE AREAS JUST NORTH OF THE SURFACE LOW CENTER
TRACK. MAINLY SNOW IS EXPECTED WITHIN THESE AREAS...WITH A WINTRY
MIX OF PRECIP EXPECTED FOR OUR NEARSHORE AREAS SOUTH OF THE ADVISORY
AREAS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
LHZ345>348.
LM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR LMZ341-
342.
LS...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR LSZ321-
322.
&&
$$
UPDATE...FARINA
NEAR TERM...MLR
SHORT TERM...SWR
LONG TERM...SWR
AVIATION...MLR
MARINE...MLR
AREA FORECAST DISCUSSION
NWS GAYLORD MI
600 AM EST FRI JAN 15 2016
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 306 AM EST FRI JAN 15 2016
SURFACE LOW CENTER HAS REACHED SRN WISCONSIN EARLY THIS MORNING...
WITH THE ASSOCIATED WARM FRONT EXTENDING EASTWARD FROM THE LOW
CENTER THRU SRN LWR MICHIGAN. MODELS CONTINUE TO OVER-FORECAST
PRECIP ALONG AND NORTH OF THIS WARM FRONT. LATEST LOOK AT KAPX SHOWS
ONLY PATCHY LIGHT FREEZING DRIZZLE AND/OR FLURRIES LINGERING ACROSS
MANLY THE NRN HALF OF OUR CWA IN THE WAKE OF AN AREA OF LIGHT SNOW
THAT HAS PUSHED NORTH OF OUR CWA. A VERY LIGHT MIST/FREEZING DRIZZLE
IS FALLING HERE AT THE GAYLORD OFFICE...WHICH MAKES SENSE LOOKING AT
OUR MODEL SOUNDINGS FOR EARLY THIS MORNING. LOW LEVELS ARE SATURATED
THRU ABOUT 850 MB...WITH A THICK LAYER OF DRY AIR AT MID LEVELS...
AND THEN ADDITIONAL MOISTURE ABOVE 600 MB. LOW LEVEL MOISTURE COMES
NOWHERE NEAR THE -10 C ISOTHERM AND SURFACE TEMPS REMAIN WELL BELOW
FREEZING AT THIS HOUR...THUS THE PATCHY LIGHT FREEZING DRIZZLE.
BOTH THE LATEST RAP13 AND THE HRRR SHOW ONLY SMALL CHANCES OF LIGHT
PRECIP EARLY THIS MORNING ACROSS MOST OF OUR CWA THRU DAYBREAK...
WITH SOME INDICATION OF GRADUALLY INCREASING POPS AS WE HEAD THRU
THE DAY IN RESPONSE TO INCREASING LIFT AND MOISTURE NEAR THE SURFACE
LOW CENTER. HIGHEST POPS ACTUALLY DEVELOP ACROSS THE SE HALF OF OUR
CWA THIS AFTERNOON JUST AHEAD OF THE SURFACE LOW CENTER AS IT TRACKS
NE THRU NRN LWR MICHIGAN. MODEL SOUNDINGS STILL SUGGEST A RATHER
TIGHT LOW LEVEL THERMAL GRADIENT WILL SET UP ACROSS OUR SRN CWA
TODAY AS THE LOW TRACKS RIGHT OVERHEAD. BASED ON MODEL SOUNDINGS...
PRECIP SHOULD REMAIN ALL SNOW ACROSS ERN UPR MICHIGAN AND THE TIP OF
THE MITT...WITH A MIX OF RAIN/SNOW AND POSSIBLY SOME FREEZING RAIN
AND SLEET MIXING IN AT TIMES ALONG THE TIGHT TEMP GRADIENT. PRECIP
WILL LIKELY BECOME ALL RAIN FOR PORTIONS OF OUR SRN CWA AND
ESPECIALLY OUR SE CWA FROM ROGERS CITY TO HOUGHTON LAKE EASTWARD AS
THE WARMEST AIR SURGES NORTHWARD IN THE AFTERNOON WITHIN THIS AREA
JUST AHEAD OF THE SURFACE LOW CENTER. WITH HIGH TEMPS WARMING INTO
THE MID TO UPPER 30S ACROSS MOST OF NRN LWR MICHIGAN...DO NOT EXPECT
ANY SIGNIFICANT ICE ACCUMULATION...BUT WILL CERTAINLY KEEP A CLOSE
EYE ON PRECIP TYPE AND DURATION AS THIS EVENT UNFOLDS. PRIMARY
CHANGES TO THE FORECAST WILL BE TO DECREASE POPS...ESPECIALLY THIS
MORNING BASED ON NEAR TERM OBSERVED AND MODEL TRENDS. CAA KICKS IN
IN THE WAKE OF THE DEPARTING LOW TONIGHT...SWITCHING PRECIP TYPE
BACK OVER TO ALL SNOW. ALSO...OVER-LAKE INSTABILITY WILL AGAIN
INCREASE WITH ONGOING CAA...TARGETING NW FLOW AREAS FOR HIGHEST POPS
TONIGHT. NEW SNOW ACCUMULATIONS WILL BE A GENERAL 1 TO 3 INCHES
TODAY FOR OUR NRN CWA...WITH ANOTHER INCH OR SO TONIGHT.
&&
.SHORT TERM...(SATURDAY THROUGH SUNDAY NIGHT)
ISSUED AT 306 AM EST FRI JAN 15 2016
SATURDAY AND SUNDAY...COLD AND SNOWY WEATHER TO CONTINUE ACROSS THE
GREAT LAKES REGION THIS WEEKEND. A STORM SYSTEM OVER THE EASTERN
LAKES SATURDAY WILL EXIT NORTHEAST INTO QUEBEC SUNDAY...WHILE AN
UPPER LVL SYSTEM SETTLES INTO THE REGION. MODEL SOUNDINGS AND MSTR
PROGS SHOW MID LVL DRYING (700/500MB RH UNDER 50 PCT) SATURDAY
AFTERNOON AS THE SFC LOW LIFTS NORTHEAST INTO QUEBEC...DIMINISHING
SNOWFALL ACROSS NORTHEAST LOWER SATURDAY AFTERNOON AND EVENING.
HOWEVER LAKE EFFECT PARAMETERS WILL STRENGTHEN SATURDAY AFTERNOON
ACRS THE WRN LAKES...WITH 850MB TEMPS FALLING TO -16C WHILE LOW LVL
INVERSION HEIGHTS INCREASE TO 4K FEET. SFC-850MB WINDS WILL
TRANSITION FROM NORTHWEST TO WEST THROUGH SATURDAY AFTERNOON IN
DIMINISHING CYCLONIC FLOW ON THE BACKSIDE OF THE EXITING STORM
SYSTEM. OVERALL WILL DIMINISH POPS ACROSS NORTHEAST LOWER SATURDAY
MORNING AS DRY MID LVL AIR SETTLES OVER THE REGION...WITH AT LEAST
LIKELY POPS OVER THE WRN LAKES THROUGH SATURDAY EVENING DUE TO LAKE
EFFECTS
SIGNIFICANT SNOW IS POSSIBLE SUNDAY FOR PORTIONS OF NRN MI...THE
COMBINATION OF AN UPPER LOW DROPPING INTO THE GREAT LAKES AS MID LVL
MSTR INCREASES AND LAKE EFFECT PARAMETERS STRENGTHEN. 700/500MB RH
INCREASES TO GREATER THAN 90 PCT SUNDAY WHILE 850/500MB QVECTOR
CONVERGENCE SHOWS STRONG FORCING OVER NRN MI IN ADVANCE OF
APPROACHING UPPER LOW. MODEL SOUNDINGS CONTINUE TO SHOW LAKE
PARAMETERS IMPROVING THROUGH THE DAY SUNDAY AS 850MB TEMPS DROP TO
-24C...INVERSION HEIGHTS INCREASE TO NEARLY 9KT WITH ABUNDANCE MSTR
THROUGH THE COLUMN. LAKES BANDS WILL BE HIGHLY UNORGANIZED THROUGH
18Z SUNDAY AS SFC-850MB WINDS SHIFT FROM SOUTHWEST TO WEST BEFORE
FINALLY LOCKING IN NORTHWEST SUNDAY EVENING INTO MONDAY. OVERALL
WILL MENTION SNOW FOR THE ENTIRE CWA SUNDAY WITH LAKE ENHANCEMENTS
FORCING HIGHEST POPS OVER THE WRN LAKES.
HIGH TEMPERATURES THIS WEEKEND WILL FALL FROM NEAR SEASONAL READINGS
IN THE 20S SATURDAY TO BETWEEN 10 AND 15 DEGREES SUNDAY AS 850MB
TEMPS PLUNGE TO -24C IN DEEPENING UPPER TROUGH.
&&
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 306 AM EST FRI JAN 15 2016
MONDAY THROUGH THURSDAY...SURFACE AND UPPER LVL STORM SYSTEMS WILL
BE IN PLACE OVER THE GREAT LAKES TO BEGIN THE UPCOMING WORK
WEEK...BEFORE SLOWLY EXITING EAST OF THE REGION TUESDAY. THIS
PATTERN WILL GENERATE SNOW ACROSS MUCH OF NORTHERN MICHIGAN MONDAY
WITH LAKE EFFECT SNOW OVER THE WRN LAKES TUESDAY...DUE TO LINGERING
CYCLONIC FLOW ON THE BACK SIDE OF THE EXITING STORM SYSTEM (NW WINDS
SFC-850MB WITH INVERSION HEIGHTS TO 6K FT). TEMPERATURES WILL BE
BELOW NORMAL THROUGH TUESDAY AS 850MB TEMPS IN THE BASE OF THE 500MB
TROUGH DROP TO -24C...FORCING DAYTIME HIGHS TO REMAIN IN THE TEENS
WITH LOWS IN THE SINGLE DIGITS.
WEDNESDAY AND THURSDAY ARE CURRENTLY TRENDING LESS ACTIVE WHEN
COMPARED TO THE PAST WEEK. A LARGE AREA OF HIGH PRESSURE AND DRY AIR
WILL SETTLE OVER THE ENTIRE GREAT LAKES AND OHIO VALLEY BY MID
WEEK...WHILE 500MB HEIGHTS INCREASE ACROSS THE UPPER MIDWEST. ANY
LAKE INFLUENCES WEDNESDAY AND THURSDAY WILL BE HINDERED BY LACK OF
OVER WATER INSTABILITY WITH 850MB TEMPS WARMING TO -8C THURSDAY. THE
WARMING IN MID LVLS WILL HELP DAYTIME TEMPS TREND CLOSER TO MID
JANUARY SEASONAL LEVELS IN THE LOWER 20S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 600 AM EST FRI JAN 15 2016
PATCHY FREEZING DRIZZLE WILL CONTINUE TO IMPACT NRN LWR MICHIGAN
THIS MORNING BEFORE BETTER CHANCES OF MEASURABLE PRECIP DEVELOPS
THIS AFTERNOON AND TONIGHT. A MIX OF RAIN AND/OR SNOW IS POSSIBLE
THIS AFTERNOON AHEAD OF LOW PRESSURE TRACKING DIRECTLY OVER NRN
LWR MICHIGAN. THE BEST CHANCE OF MIXED PRECIP WILL BE AROUND
APN...TVC AND MBL. PLN WILL LIKELY REMAIN ALL SNOW JUST NORTH OF
THE TRACK OF THE SURFACE LOW. OVERALL PRECIP INTENSITY WILL REMAIN
LIGHT ACROSS THE ENTIRE REGION. ALL PRECIP WILL AGAIN BECOME ALL
SNOW BY LATE EVENING AS CAA COMMENCES IN THE WAKE OF THE DEPARTING
LOW. CONDITIONS WILL REMAIN IFR TO LOW MVFR THRU THE ENTIRE TAF
FORECAST PERIOD. EAST WIND AROUND 10 KTS TODAY WILL SHIFT TO THE
N/NW BEHIND THE LOW TONIGHT WITH GUSTS TO 20 KTS EXPECTED.
&&
.MARINE...
ISSUED AT 306 AM EST FRI JAN 15 2016
WINDS AND WAVES WILL REMAIN JUST AT SCA CRITERIA THRU MUCH OF TODAY
FOR OUR NRN NEARSHORE AREAS JUST NORTH OF THE SURFACE LOW CENTER
TRACK. MAINLY SNOW IS EXPECTED WITHIN THESE AREAS...WITH A WINTRY
MIX OF PRECIP EXPECTED FOR OUR NEARSHORE AREAS SOUTH OF THE ADVISORY
AREAS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
LHZ345>348.
LM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR LMZ341-
342.
LS...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR LSZ321-
322.
&&
$$
NEAR TERM...MLR
SHORT TERM...SWR
LONG TERM...SWR
AVIATION...MLR
MARINE...MLR
AREA FORECAST DISCUSSION
NWS GAYLORD MI
306 AM EST FRI JAN 15 2016
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 306 AM EST FRI JAN 15 2016
SURFACE LOW CENTER HAS REACHED SRN WISCONSIN EARLY THIS MORNING...
WITH THE ASSOCIATED WARM FRONT EXTENDING EASTWARD FROM THE LOW
CENTER THRU SRN LWR MICHIGAN. MODELS CONTINUE TO OVER-FORECAST
PRECIP ALONG AND NORTH OF THIS WARM FRONT. LATEST LOOK AT KAPX SHOWS
ONLY PATCHY LIGHT FREEZING DRIZZLE AND/OR FLURRIES LINGERING ACROSS
MANLY THE NRN HALF OF OUR CWA IN THE WAKE OF AN AREA OF LIGHT SNOW
THAT HAS PUSHED NORTH OF OUR CWA. A VERY LIGHT MIST/FREEZING DRIZZLE
IS FALLING HERE AT THE GAYLORD OFFICE...WHICH MAKES SENSE LOOKING AT
OUR MODEL SOUNDINGS FOR EARLY THIS MORNING. LOW LEVELS ARE SATURATED
THRU ABOUT 850 MB...WITH A THICK LAYER OF DRY AIR AT MID LEVELS...
AND THEN ADDITIONAL MOISTURE ABOVE 600 MB. LOW LEVEL MOISTURE COMES
NOWHERE NEAR THE -10 C ISOTHERM AND SURFACE TEMPS REMAIN WELL BELOW
FREEZING AT THIS HOUR...THUS THE PATCHY LIGHT FREEZING DRIZZLE.
BOTH THE LATEST RAP13 AND THE HRRR SHOW ONLY SMALL CHANCES OF LIGHT
PRECIP EARLY THIS MORNING ACROSS MOST OF OUR CWA THRU DAYBREAK...
WITH SOME INDICATION OF GRADUALLY INCREASING POPS AS WE HEAD THRU
THE DAY IN RESPONSE TO INCREASING LIFT AND MOISTURE NEAR THE SURFACE
LOW CENTER. HIGHEST POPS ACTUALLY DEVELOP ACROSS THE SE HALF OF OUR
CWA THIS AFTERNOON JUST AHEAD OF THE SURFACE LOW CENTER AS IT TRACKS
NE THRU NRN LWR MICHIGAN. MODEL SOUNDINGS STILL SUGGEST A RATHER
TIGHT LOW LEVEL THERMAL GRADIENT WILL SET UP ACROSS OUR SRN CWA
TODAY AS THE LOW TRACKS RIGHT OVERHEAD. BASED ON MODEL SOUNDINGS...
PRECIP SHOULD REMAIN ALL SNOW ACROSS ERN UPR MICHIGAN AND THE TIP OF
THE MITT...WITH A MIX OF RAIN/SNOW AND POSSIBLY SOME FREEZING RAIN
AND SLEET MIXING IN AT TIMES ALONG THE TIGHT TEMP GRADIENT. PRECIP
WILL LIKELY BECOME ALL RAIN FOR PORTIONS OF OUR SRN CWA AND
ESPECIALLY OUR SE CWA FROM ROGERS CITY TO HOUGHTON LAKE EASTWARD AS
THE WARMEST AIR SURGES NORTHWARD IN THE AFTERNOON WITHIN THIS AREA
JUST AHEAD OF THE SURFACE LOW CENTER. WITH HIGH TEMPS WARMING INTO
THE MID TO UPPER 30S ACROSS MOST OF NRN LWR MICHIGAN...DO NOT EXPECT
ANY SIGNIFICANT ICE ACCUMULATION...BUT WILL CERTAINLY KEEP A CLOSE
EYE ON PRECIP TYPE AND DURATION AS THIS EVENT UNFOLDS. PRIMARY
CHANGES TO THE FORECAST WILL BE TO DECREASE POPS...ESPECIALLY THIS
MORNING BASED ON NEAR TERM OBSERVED AND MODEL TRENDS. CAA KICKS IN
IN THE WAKE OF THE DEPARTING LOW TONIGHT...SWITCHING PRECIP TYPE
BACK OVER TO ALL SNOW. ALSO...OVER-LAKE INSTABILITY WILL AGAIN
INCREASE WITH ONGOING CAA...TARGETING NW FLOW AREAS FOR HIGHEST POPS
TONIGHT. NEW SNOW ACCUMULATIONS WILL BE A GENERAL 1 TO 3 INCHES
TODAY FOR OUR NRN CWA...WITH ANOTHER INCH OR SO TONIGHT.
&&
.SHORT TERM...(SATURDAY THROUGH SUNDAY NIGHT)
ISSUED AT 306 AM EST FRI JAN 15 2016
SATURDAY AND SUNDAY...COLD AND SNOWY WEATHER TO CONTINUE ACROSS THE
GREAT LAKES REGION THIS WEEKEND. A STORM SYSTEM OVER THE EASTERN
LAKES SATURDAY WILL EXIT NORTHEAST INTO QUEBEC SUNDAY...WHILE AN
UPPER LVL SYSTEM SETTLES INTO THE REGION. MODEL SOUNDINGS AND MSTR
PROGS SHOW MID LVL DRYING (700/500MB RH UNDER 50 PCT) SATURDAY
AFTERNOON AS THE SFC LOW LIFTS NORTHEAST INTO QUEBEC...DIMINISHING
SNOWFALL ACROSS NORTHEAST LOWER SATURDAY AFTERNOON AND EVENING.
HOWEVER LAKE EFFECT PARAMETERS WILL STRENGTHEN SATURDAY AFTERNOON
ACRS THE WRN LAKES...WITH 850MB TEMPS FALLING TO -16C WHILE LOW LVL
INVERSION HEIGHTS INCREASE TO 4K FEET. SFC-850MB WINDS WILL
TRANSITION FROM NORTHWEST TO WEST THROUGH SATURDAY AFTERNOON IN
DIMINISHING CYCLONIC FLOW ON THE BACKSIDE OF THE EXITING STORM
SYSTEM. OVERALL WILL DIMINISH POPS ACROSS NORTHEAST LOWER SATURDAY
MORNING AS DRY MID LVL AIR SETTLES OVER THE REGION...WITH AT LEAST
LIKELY POPS OVER THE WRN LAKES THROUGH SATURDAY EVENING DUE TO LAKE
EFFECTS
SIGNIFICANT SNOW IS POSSIBLE SUNDAY FOR PORTIONS OF NRN MI...THE
COMBINATION OF AN UPPER LOW DROPPING INTO THE GREAT LAKES AS MID LVL
MSTR INCREASES AND LAKE EFFECT PARAMETERS STRENGTHEN. 700/500MB RH
INCREASES TO GREATER THAN 90 PCT SUNDAY WHILE 850/500MB QVECTOR
CONVERGENCE SHOWS STRONG FORCING OVER NRN MI IN ADVANCE OF
APPROACHING UPPER LOW. MODEL SOUNDINGS CONTINUE TO SHOW LAKE
PARAMETERS IMPROVING THROUGH THE DAY SUNDAY AS 850MB TEMPS DROP TO
-24C...INVERSION HEIGHTS INCREASE TO NEARLY 9KT WITH ABUNDANCE MSTR
THROUGH THE COLUMN. LAKES BANDS WILL BE HIGHLY UNORGANIZED THROUGH
18Z SUNDAY AS SFC-850MB WINDS SHIFT FROM SOUTHWEST TO WEST BEFORE
FINALLY LOCKING IN NORTHWEST SUNDAY EVENING INTO MONDAY. OVERALL
WILL MENTION SNOW FOR THE ENTIRE CWA SUNDAY WITH LAKE ENHANCEMENTS
FORCING HIGHEST POPS OVER THE WRN LAKES.
HIGH TEMPERATURES THIS WEEKEND WILL FALL FROM NEAR SEASONAL READINGS
IN THE 20S SATURDAY TO BETWEEN 10 AND 15 DEGREES SUNDAY AS 850MB
TEMPS PLUNGE TO -24C IN DEEPENING UPPER TROUGH.
&&
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 306 AM EST FRI JAN 15 2016
MONDAY THROUGH THURSDAY...SURFACE AND UPPER LVL STORM SYSTEMS WILL
BE IN PLACE OVER THE GREAT LAKES TO BEGIN THE UPCOMING WORK
WEEK...BEFORE SLOWLY EXITING EAST OF THE REGION TUESDAY. THIS
PATTERN WILL GENERATE SNOW ACROSS MUCH OF NORTHERN MICHIGAN MONDAY
WITH LAKE EFFECT SNOW OVER THE WRN LAKES TUESDAY...DUE TO LINGERING
CYCLONIC FLOW ON THE BACK SIDE OF THE EXITING STORM SYSTEM (NW WINDS
SFC-850MB WITH INVERSION HEIGHTS TO 6K FT). TEMPERATURES WILL BE
BELOW NORMAL THROUGH TUESDAY AS 850MB TEMPS IN THE BASE OF THE 500MB
TROUGH DROP TO -24C...FORCING DAYTIME HIGHS TO REMAIN IN THE TEENS
WITH LOWS IN THE SINGLE DIGITS.
WEDNESDAY AND THURSDAY ARE CURRENTLY TRENDING LESS ACTIVE WHEN
COMPARED TO THE PAST WEEK. A LARGE AREA OF HIGH PRESSURE AND DRY AIR
WILL SETTLE OVER THE ENTIRE GREAT LAKES AND OHIO VALLEY BY MID
WEEK...WHILE 500MB HEIGHTS INCREASE ACROSS THE UPPER MIDWEST. ANY
LAKE INFLUENCES WEDNESDAY AND THURSDAY WILL BE HINDERED BY LACK OF
OVER WATER INSTABILITY WITH 850MB TEMPS WARMING TO -8C THURSDAY. THE
WARMING IN MID LVLS WILL HELP DAYTIME TEMPS TREND CLOSER TO MID
JANUARY SEASONAL LEVELS IN THE LOWER 20S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1154 PM EST THU JAN 14 2016
LOW PRESSURE WILL MOVE ACROSS NORTHERN MICHIGAN TODAY AND INTO
LAKE HURON LATER TONIGHT. THIS TRACK WILL BRING MILDER AIR UP
FROM THE SOUTH. ANY LIGHT SNOW WILL MIX WITH AND CHANGE OVER TO
RAIN...POSSIBLY EVEN A PERIOD OF FREEZING RAIN BEFORE
TRANSITIONING BACK OVER TO SNOW LATE FRIDAY...WITH AREAS OF
FREEZING DRIZZLE AND DRIZZLE MIXED IN EARLY THIS MORNING. CIGS
WILL BE DROPPING THROUGH MVFR TO IFR OVERNIGHT AND LIFR FOR A TIME
TODAY BEFORE LIKELY REBOUNDING BACK TO IFR THIS EVENING.
&&
.MARINE...
ISSUED AT 306 AM EST FRI JAN 15 2016
WINDS AND WAVES WILL REMAIN JUST AT SCA CRITERIA THRU MUCH OF TODAY
FOR OUR NRN NEARSHORE AREAS JUST NORTH OF THE SURFACE LOW CENTER
TRACK. MAINLY SNOW IS EXPECTED WITHIN THESE AREAS...WITH A WINTRY
MIX OF PRECIP EXPECTED FOR OUR NEARSHORE AREAS SOUTH OF THE ADVISORY
AREAS.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
LHZ345>348.
LM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR LMZ341-
342.
LS...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR LSZ321-
322.
&&
$$
NEAR TERM...MLR
SHORT TERM...SWR
LONG TERM...SWR
AVIATION...SULLIVAN
MARINE...MLR
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1217 AM EST FRI JAN 15 2016
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 258 PM EST THU JAN 14 2016
ONE LOW PRESSURE SYSTEM IN IOWA WILL TRACK EAST TONIGHT AND
THROUGH MICHIGAN ON FRIDAY. THIS SYSTEM COULD PRODUCE SOME LIGHT
RAIN. A COLDER AIRMASS RETURNS TO THE REGION FRIDAY NIGHT INTO
SATURDAY WITH LAKE EFFECT SNOW SHOWERS POSSIBLE NEAR THE
LAKESHORE. A REINFORCING SHOT OF ARCTIC AIR ARRIVES SUNDAY WITH
ACCUMULATING LAKE EFFECT SNOW LIKELY.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 258 PM EST THU JAN 14 2016
GIVEN THE CLEARING SKIES AND WARM AIR ADVECTION I DOWNPLAYED THE
POTENTIAL FOR SLEET AND FREEZING RAIN TONIGHT. STILL THE NORTHEAST
COUNTIES WILL BE CLOSE TO THE WARM FRONT AND A SMALL RISK EXISTS
UP THERE. TOO LOW FOR ANY HEADLINE AT THIS POINT. THE HRRR RUC WAS
SHOWING FOG TRYING TO DEVELOP LATER TONIGHT. I ADDED THIS TO THE
FORECAST.
A BETTER RISK FOR MEASURABLE RAIN EXISTS FOR FRIDAY. THE WAVE OF
LOW PRESSURE TRACKS EASTWARD THROUGH THE CWA. ENOUGH FORCING AND
MOISTURE AROUND FOR LIGHT RAIN. AT THIS POINT IT APPEARS THAT MOST
LOCATIONS WILL SEE LESS THAN A QUARTER INCH.
COLDER AIR RETURNS QUICKLY BEHIND THE DEPARTING LOW. THUS FRIDAY
NIGHT LOOKS LIKE MAINLY SNOW...IF ANY PRECIPITATION AT ALL. I AM
NOT CONFIDENT THAT WE WILL SEE MUCH PRECIPITATION AS THIS INITIAL
COLDER AIRMASS BEHIND THE LOW IS NOT THAT COLD...850 MB TEMPS DOWN
TO -8 DEG C OR SO. A BETTER SURGE OF ARCTIC AIR MOVES IN FOR LATER
SATURDAY NIGHT.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 258 PM EST THU JAN 14 2016
WE STILL EXPECT A FEW INCHES OF LAKE EFFECT SNOW ON SUNDAY AND INTO
MONDAY. THE BULK OF THIS WILL FALL ON SUNDAY WITH A GENERAL 3 TO 5
INCHES ACROSS THE WESTERN ZONES. SNOW SHOWERS SHOULD REACH FAR
INLAND AS THE FLOW WILL BE FROM ABOUT 280 DEGREES WITH SOME ENHANCED
LOW LEVEL CONVERGENCE POSSIBLE ACROSS THE SOUTHERN HALF OF THE
FORECAST AREA.
SUNDAY ALSO LOOKS MIGHTY COLD WITH 850 MB TEMPS BLO MINUS 20C AND
STRONG CAA ALL DAY. CORE OF THE COLDEST AIR COMES THROUGH DURING THE
AFTERNOON AND EVENING SO MAX TEMPS MIGHT OCCUR SUNDAY MORNING WITH
STEADY FOR FALLING TEMPERATURES DURING THE DAY AND WIND CHILLS
POSSIBLY GETTING DOWN TO 10 BELOW DURING THE EVENING.
MONDAY WILL SEE LAKE EFFECT SNOW SHOWERS CONTINUE WITH CYCLONIC FLOW
BUT ACCUMS ARE LIMITED BY INVERSION HEIGHTS AOB 5 KFT AND THE DGZ
NEAR THE SFC...SO ONLY ANOTHER INCH OR TWO EXPECTED.
THERE WILL BE A SLOW MODERATION IN TEMPERATURES FROM TUESDAY THROUGH
THURSDAY. IT REMAINS COLD ENOUGH FOR OCCASIONAL LAKE EFFECT SNOW
SHOWERS...ALTHOUGH AMOUNTS ARE EXPECTED TO BE LIGHT AS INVERSION
HEIGHTS REMAIN AOB 5 KFT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1215 AM EST FRI JAN 15 2016
AREAS OF MVFR FOG TONIGHT... WITH MVFR CIGS DEVELOPING FRIDAY
MORNING FOLLOWED BY WIDESPREAD IFR TO LIFR CIGS IN THE AFTERNOON
WHEN RAIN AND DRIZZLE BECOME MORE WIDESPREAD. LLWS THROUGH 12Z
FRIDAY WITH SOUTHWEST WINDS OF 40 KTS AT 2000 FT AND SFC WINDS
AROUND 10 KTS FROM THE SOUTHEAST.
&&
.MARINE...
ISSUED AT 258 PM EST THU JAN 14 2016
SOUTH TO SOUTHEAST WINDS WILL INCREASE TONIGHT. THIS WILL CAUSE
WAVES TO BUILD CLOSE TO SMALL CRAFT ADVISORY CRITERIA. THE WINDS
WILL VEER TO THE NORTHWEST BY FRIDAY NIGHT. AS COLDER AIR WORKS IT
WAY IN THE WAVES WILL BUILD TO OVER 4 FEET. HAZARDOUS CONDITIONS
FOR SMALL CRAFT WILL PERSIST THROUGH THE WEEKEND.
&&
.HYDROLOGY...
ISSUED AT 108 PM EST THU JAN 14 2016
ICE JAMMING IS LIKELY AFFECTING THE GRAND RIVER AT ROBINSON
TOWNSHIP. WARMER TEMPERATURES ALONG WITH SOME RAINFALL FRIDAY MAY
HELP LOOSEN THE JAM AND SOFTEN THE ICE FURTHER. THE FLOATING ICE
ON THE RIVER DOES NOT LOOK PARTICULARLY THICK SO IT MAY NOT TAKE
MUCH TO FREE THE JAM UP WITH MORE FAVORABLE WEATHER CONDITIONS
THROUGH FRIDAY. ELSEWHERE THERE IS LIKELY SOME ICE BUILDING
UPSTREAM OF DIMONDALE ON THE GRAND RIVER. HOWEVER...THE RIVER
STAGE AT DIMONDALE IS WELL BELOW BANKFULL PRESENTLY. WE WILL
CONTINUE TO MONITOR AREA RIVERS. A DEEP FREEZE LATER THIS WEEKEND
INTO NEXT WEEK WILL PUT A STOP TO ICE MOVEMENT AND WILL ALLOW FOR
ICE TO REDEVELOP. IF THE ROBINSON TWP JAM DOES NOT RELEASE BY THE
TIME THE ARCTIC AIR ARRIVES THEN MORE SIGNIFICANT ISSUES MAY
DEVELOP POTENTIALLY...WITH FURTHER ICE FORMATION OCCURRING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...OSTUNO
AVIATION...MEADE
HYDROLOGY...HOVING
MARINE...MJS
AREA FORECAST DISCUSSION
NWS DULUTH MN
355 PM CST FRI JAN 15 2016
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 354 PM CST FRI JAN 15 2016
MAIN CONCERN FOR THE NEXT 24 HOURS IS LAKE EFFECT SNOW OVER THE
SOUTH SHORE LAKE EFFECT AREAS OF NORTHWEST WISCONSIN...AND THE
ARCTIC AIRMASS THAT WILL BE BRINGING IN VERY COLD TEMPERATURES FOR
THE WEEKEND.
STRONG COLD AIR ADVECTION ACROSS MUCH OF MINNESOTA AND WISCONSIN
TONIGHT WILL BRING IN A VERY COLD AIRMASS FOR SATURDAY...WITH 850MB
TEMPERATURES DOWN AROUND 25 BELOW SATURDAY AT 18Z OVER THE NORTHERN
FORECAST AREA. THIS IS GOING TO CAUSE SURFACE TEMPERAURES TO TAKE A
NOSE DIVE AS WELL...WITH LOW TEMPERATURES TONIGHT FALLING TO BETWEEN
ZERO AND 10 BELOW OVER NORTHWEST WISCONSIN TO 8 TO 18 BELOW OVER
NORTHEAST MINNESOTA. CLOUD COVER IS GOING TO HAVE A FAIRLY LARGE
EFFECT ON THIS...AS THE CLOUD COVER OVER THE AREA IS GOING TO BE
SHUNTED SOUTH WITH THE BAROCLINIC ZONE...AND AN AREA OF CLEAR SKIES
WILL MOVE IN THIS EVENING. HOWEVER...THIS IS NOT A VERY LARGE AREA
OF CLEARING AND MODELS KEEP LOW LEVEL RH VALUES FAIRLY HIGH AND AM
CONCERNED THAT WE WILL HAVE MORE CLOUD COVER. HOWEVER...ALL IT TAKES
IS A SHORT PERIOD OF CLEAR SKIES FOR TEMPERATURES TO REALLY DROP
OFF...EVEN IF THEY RISE AGAIN AFTER THE CLOUDS MOVE IN. NORTHWEST
WINDS OF 5 TO 15 MPH ARE EXPECTED TO PRODUCE WIND CHILL VALUES OF 20
TO 35 BELOW FOR ENOUGH OF THE NIGHT THAT THE WIND CHILL ADVISORY
STILL LOOKS APPROPRIATE FOR TONIGHT AND SATURDAY MORNING.
THE COLD AIR MOVING INTO THE AREA IS GOING TO PRODUCE ANOTHER ROUND
OF LAKE EFFECT SNOW TONIGHT AND SATURDAY FOR THE SOUTH SHORE OF LAKE
SUPERIOR. IN FACT...IT IS ALREADY AFFECTING PORTIONS OF DOUGLAS AND
BAYFIELD COUNTY. SO FAR THE SNOWFALL RATES APPEAR PRETTY LIGHT...BUT
EXPECT THE SNOWFALL TO INTENSIFY AS THE COLDER AIR MOVES IN ALOFT.
850MB TEMPS GO FROM AROUND -12 THIS AFTERNOON TO -18Z BY 12Z...WITH
THE BEST LAYER MOISTURE BETWEEN 06Z AND 12Z. SNOWFALL AMOUNTS OF 3
TO 5 INCHES CAN BE EXPECTED OVER THE NEXT 24 HOURS. THIS IS VERY
CLOSE TO AN ADVISORY...AND WOULD NOT BE SURPRISED IF THE SNOWFALL
RATES LOOK BETTER UPON THE ONSET OF THE SNOW THAT WE MAY NEED TO
ISSUE AN ADVISORY.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 354 PM CST FRI JAN 15 2016
A POLAR LOW WILL DROP OUT OF CANADA TO WESTERN LAKE SUPERIOR
SATURDAY NIGHT...AND SURFACE HIGH PRESSURE WILL BE EAST OF THE ROCKY
MOUNTAINS. THE NW FLOW WILL BRING A VERY COLD AIR MASS TO THE
NORTHLAND...THE COLDEST THE NORTHLAND HAS YET SEEN THIS WINTER. THE
850 HPA TEMPERATURES WILL DROP TO ABOUT -26 TO
-30 DEGREES CELSIUS EARLY SUNDAY. CLOUD COVER AND 5 TO 15 MPH WNW
WIND SPEEDS WILL LIKELY BOLSTER OVERNIGHT TEMPERATURES...SO SLIGHTLY
LEANED ON THE WARMER MODEL GUIDANCE FOR THE LOW TEMPERATURE FOR MY
BLEND...SUCH AS THE NAM AND CANADIAN. THE LOWS SHOULD PRIMARILY BE
IN THE TEENS BELOW ZERO...BUT SOME AREAS IN THE WEST COULD FLIRT
WITH 20 DEGREES BELOW ZERO. WIDESPREAD WIND CHILLS OF 30 TO 40 BELOW
ZERO ARE LIKELY.
THE POLAR LOW WILL SHIFT EAST INTO EASTERN CANADA SUNDAY INTO
MONDAY...AND THE SURFACE HIGH PRESSURE WILL MOVE EAST INTO THE
PLAINS. THE CLOUD COVER WILL LIKELY LINGER SUNDAY MORNING...BUT
THERE COULD BE SOME CLEARING LATE SUNDAY INTO MONDAY. THE HIGH
TEMPERATURES ON SUNDAY WILL BE THE COLDEST YET THIS SEASON. HIGHS
WILL BE AROUND -5 DEGREES...BUT NOT QUITE DAILY RECORD TERRITORY.
THE LIGHTER WINDS AND CLEARER SKIES SUNDAY NIGHT...AND THE FACT THAT
SUNDAY AFTERNOON WILL BE SO COLD...SHOULD BE A RECIPE FOR EVEN
COLDER LOW TEMPERATURES FOR SUNDAY NIGHT. LEANED ON THE COLDER MODEL
GUIDANCE...INCLUDING THE CANADIAN. LIKED HOW THE CANADIAN HAD ITS
COLDEST TEMPERATURES ACROSS THE WEST...WHERE IT WILL MORE LIKELY BE
CLEAR WITH THE LIGHTEST WIND SPEEDS. MUCH OF THE REGION WILL SEE
LOWS APPROACH OR REACH -20 DEGREES. MONDAY SHOULD BE WARMER THAN
SUNDAY...PARTLY DUE TO MORE SUNSHINE...SO LEANED ON THE WARMER MODEL
GUIDANCE WITH HIGHS AROUND 0 DEGREES. SUNDAY NIGHT AND MONDAY
MORNING WIND CHILLS WILL LIKELY BE 25 TO 35 BELOW ZERO.
THE COLD NW TO WNW FLOW OVER WESTERN LAKE SUPERIOR WILL RESULT IN A
PROLONGED PERIOD OF LIGHT LAKE EFFECT SNOW FOR DOWNWIND AREAS OF NW
WISCONSIN SATURDAY NIGHT THROUGH MONDAY. MOST OF THE SNOW WILL FALL
SATURDAY NIGHT AND SUNDAY WHEN THE FLOW IS COLDER AND MORE NW...BUT
THE FLOW WILL GET WARMER AND MORE WNW SUNDAY NIGHT AND MONDAY. PARTS
OF NORTHERN IRON COUNTY AND NORTHERN BAYFIELD PENINSULA COULD GET
SEVERAL INCHES SATURDAY NIGHT THROUGH SUNDAY.
THERE WILL LIKELY BE A WARMING TREND THROUGH THE REST OF THE WEEK AS
THE ARCTIC FLOW COMES TO AN END AND THEN PACIFIC AIR...MODIFIED BY
THE ROCKY MOUNTAINS...PUSHES INTO THE UPPER MIDWEST LATER IN THE
WEEK. HIGH TEMPERATURES COULD REACH THE UPPER TEENS AND LOW 20S BY
THURSDAY. TUESDAY LOOKS FAIRLY SUNNY DUE TO THE HIGH PRESSURE BEING
OVER THE NORTHLAND. SOME WEAK DISTURBANCES COULD BRING SOME CLOUD
COVER AND VERY LIGHT SNOW WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1123 AM CST FRI JAN 15 2016
AN AREA OF LOW PRESSURE NEAR CENTRAL LAKE MICHIGAN WILL SHIFT EAST
TOWARDS LAKE HURON TODAY...WHILE ARCTIC HIGH PRESSURE IN CANADA
WILL CONTINUE TO SHIFT SOUTH INTO THE NORTHERN PLAINS AND UPPER
MIDWEST...AND BRING THE NEXT WAVE OF FRIGID AIR.
THERE WILL BE LINGERING IFR/MVFR CONDITIONS ACROSS NE MINNESOTA
AND NW WISCONSIN TODAY...BUT MOST TERMINALS SHOULD SEE A GRADUAL
CLEARING TREND THIS AFTERNOON INTO THIS EVENING. THE EXCEPTION
WILL BE KHYR...WHERE THE MORE HUMID NORTHERLY FLOW FROM LAKE
SUPERIOR WILL MAINTAIN IFR/MVFR CEILINGS THROUGH AT LEAST THE WEE
HOURS OF SATURDAY MORNING. THE WINDS WILL BACK WITH
TIME...BECOMING MORE WNW BY LATER TONIGHT...SO THE LOW CEILINGS AT
KHYR COULD SHIFT TO JUST EAST OF KHYR BEFORE DAWN.
LESS CONFIDENT ABOUT CLOUD COVER LATER TONIGHT AND EARLY SATURDAY.
THE GFS AND HRRR ARE SUGGESTING LOW CLOUD COVER COULD REDEVELOP OR
LINGER INTO THE NIGHT...WHILE THE NAM HAS A CLEARER TREND. LEANED
ON THE NAM SINCE IT SEEMS TO BE FOLLOWING CURRENT TRENDS BETTER.
THERE COULD BE PERIODS OF VERY LIGHT FREEZING DRIZZLE MIXED IN
WITH THE VERY LIGHT SNOW AT KDLH THROUGH THIS AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH -10 -3 -17 -6 / 0 0 0 0
INL -16 -7 -19 -6 / 0 0 0 0
BRD -12 -4 -17 -4 / 0 0 10 10
HYR -6 -1 -17 -5 / 20 0 0 10
ASX 1 3 -8 -1 / 60 40 70 90
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST SATURDAY
FOR MNZ010-011-018-019-025-026-033>037.
LS...SMALL CRAFT ADVISORY UNTIL 10 PM CST THIS EVENING FOR LSZ121-
140>148.
&&
$$
SHORT TERM...LE
LONG TERM...GROCHOCINSKI
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1123 AM CST FRI JAN 15 2016
.UPDATE...
ISSUED AT 1123 AM CST FRI JAN 15 2016
UPDATE FOR THE NEW 18Z AVIATION DISCUSSION BELOW.
UPDATE ISSUED AT 1004 AM CST FRI JAN 15 2016
HAVE UPDATED THE FORECAST FOR THE FREEZING DRIZZLE/SNOW SHOWERS
THAT HAVE BLOOMED ACROSS THE ARROWHEAD THIS MORNING. WILL HAVE TO
WATCH THESE CAREFULLY AS MODELS ARE NOT HANDLING AT ALL. THE
DRIZZLE/FLURRIES SEEMS TO BE ASSOCIATED WITH A THICKER BAND OF
CLOUDS APPARENT ON VISIBLE SATELLITE...AND FROM WHAT SATELLITE
SHOWS DO NOT EXPECT IT TO EXPAND ANY FARTHER WEST...BUT IT MAY
EXPAND INTO NW WI FOR THE AFTERNOON.
UPDATE ISSUED AT 551 AM CST FRI JAN 15 2016
UPDATED FOR 12Z AVIATION DISCUSSION BELOW
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 355 AM CST FRI JAN 15 2016
A CLOSED UPPER LOW WAS LOCATED OVER NORTHERN MANITOBA AT 0815Z. AN
ASSOCIATED LONG WAVE TROF WAS WAS MOVING THROUGH MN. AT THE
SFC...THE LOW CENTER WAS LOCATED IN SW WI WITH AN INVERTED TROF
EXTENDING NWD THROUGH NW WI TO THE MN ARROWHEAD. THE INTERACTION
BETWEEN THESE FEATURES WAS CONTINUING TO PRODUCE LIGHT SNOW FROM THE
ARROWHEAD TO THE TWIN PORTS AND INTO NW WI. HOWEVER...THE SNOW HAS
LESSENED IN INTENSITY AND WILL LET THE WINTER WEATHER ADVISORY GO.
THE SFC LOW WILL MOVE INTO NORTHERN LOWER MI BY 00Z
SATURDAY....WHILE THE UPPER TROF REACHES EASTERN WI. THE BULK OF THE
ACCUMULATING SNOW WILL HAVE ENDED THIS MORNING. HOWEVER...A
TRANSITION TO SOME LAKE INDUCED SNOW SHOWERS IS EXPECTED IN THE
AFTERNOON. NOT EXPECTING A TRUE LAKE EFFECT SNOW EVENT THIS
AFTERNOON AS THE 1000-900MB LAYER REMAINS TOO WARM. WILL SEE SOME
SNOW SHOWERS AND AROUND AN INCH OF ACCUMULATION IN NW WI.
AS THE THE SFC LOW MOVES INTO SOUTHERN ONTARIO TONIGHT...COLD ARCTIC
HIGH PRESSURE BEGINS TO WORK ITS WAY INTO THE REGION. THE COLDER AIR
WILL FILTER ACROSS NW WI AS THE WIND TURNS NW. THIS WILL BEGIN TO
FAVOR A TRUE LAKE EFFECT SNOW. THIS WIND DIRECTION AND TRAJECTORIES
WOULD FAVOR SNOW SHOWERS FROM NE DOUGLAS COUNTY AND ALONG THE
BAYFIELD PENINSULA IN THE EVENING. NOT MUCH IN THE WAY OF LAKE
EFFECT FOR ASHLAND OR IRON COUNTIES AS THE WARM AIR LINGERS AND THIS
IS AN UNFAVORABLE WIND DIRECTION FOR THIS AREA. THE WARM AIR FINALLY
MOVES AWAY LATE TONIGHT AS THE WNW WIND CONTINUES AND COLD AIR
ADVECTION IS FULLY UNDERWAY. THIS AGAIN FAVORS THE AFOREMENTIONED
AREAS. HAVE ALIGNED POPS TO MATCH THIS THINKING.
ELSEWHERE...SOME CLEARING IS EXPECTED TONIGHT OVER THE WESTERN THIRD
OF THE FORECAST AREA WITH THE ARCTIC HIGH BUILDING IN. THE PRESSURE
GRADIENT WILL BEGIN TO TIGHTEN OVER THIS AREA AND WITH THE EXPECTED
MINIMUM TEMPERATURES...HAVE ISSUED A WIND CHILL ADVISORY FROM 06Z
TONIGHT TO 18Z SATURDAY.
ON SATURDAY...THE HIGH COVERS MUCH OF THE FORECAST AREA. THE
EXCEPTION BEING NW WI AND THE ARROWHEAD WHICH WILL STILL BE AFFECTED
BY A TRAILING SFC TROF FROM THE DEPARTING LOW. A WNW WIND WILL
CONTINUE OVER THE REGION ALONG WITH THE COLD AIR ADVECTION. THIS
SCENARIO FAVORS LAKE EFFECT SNOW FROM NE DOUGLAS COUNTY AND THE
BAYFIELD PENINSULA AND HAVE HIGHER POPS IN THIS AREA. LOWER POPS
OVER ASHLAND AND IRON COUNTIES. A VORT MAX WILL ROTATE OVER THE
REGION...BUT WILL LEAVE OUT THE MENTION OF FLURRIES AS THERE IS A
QUESTION OF THE EXTENT OF CLOUD COVER.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 355 AM CST FRI JAN 15 2016
FRIGID CONDITIONS WILL AMPLIFY INTO THE LATTER HALF OF THE HOLIDAY
WEEKEND. BY 00Z SUNDAY THE CENTER OF THE 500MB COLD CORE WILL
ARRIVE... SWINGING SOUTHWARD THROUGH NORTHERN MINNESOTA AND REACHING
NW WISCONSIN BY 12Z AS SFC HIGH PRESSURE BUILDS ACROSS THE DAKOTAS.
THE STRENGTH OF THE COLD CORE REMAINS ON TRACK WITH PREVIOUS MODEL
RUNS OF 850MB SAMPLES RUNNING AROUND -25C TO -30C. THEREFORE NOT
MUCH WAS NEEDED TO TWEAK THE ONGOING FORECAST. SUNDAY AND MONDAY
MORNINGS WILL BOTH SEE MIN TEMPS RANGING FROM -10F TO -25F... WITH
SLIGHTLY WARMER CONDITIONS NEAR THE LAKE. WINDS AROUND 5 MPH WILL
PRODUCE WIND CHILL TEMPS AS COLD AS -40F AT TIMES.
WIND CHILL HEADLINES WILL ALMOST CERTAINLY BE NEEDED. THE ONE
POTENTIAL COMPLICATION TO THE FORECAST WOULD BE THE DIFFERENCE IN
CLOUD COVER BETWEEN THE ECMWF/GFS AND THE NAM... WITH THE NAM
YIELDING FAR LESS CLOUD COVER... AND A MUCH QUICKER CLEARING SUNDAY
NIGHT/MONDAY MORNING THAN THE OTHER TWO MODELS. SFC HIGH PRESSURE
WILL BE BUILDING ACROSS THE NORTHERN PLAINS BUT WITH CYCLONIC FLOW
IN PLACE... DECIDED TO STAY ON THE PESSIMISTIC SIDE AND TREND
TOWARDS A CLOUDIER SOLUTION. HOWEVER IF SKIES ARE ABLE TO CLEAR OUT
MORE IN TUNE WITH THE NAM... RADIATIONAL COOLING COULD MAKE FOR AN
EVEN COLDER MONDAY MORNING. HIGH TEMPS THROUGH THE WEEKEND WILL
STRUGGLE TO RISE ABOVE ZERO FOR MOST OF THE CWA.
PROLONGED NORTHWESTERLY FLOW ACROSS THE OPEN WATERS OF LAKE SUPERIOR
ALONG WITH COLD TEMPERATURES ALOFT WILL SUPPORT LAKE EFFECT SNOW
ACROSS NW WISCONSIN THROUGH THE EARLY PART OF NEXT WEEK... WITH
CHANCES HIGHEST FOR NORTHERN BAYFIELD... ASHLAND... IRON AND PRICE
COUNTIES. MAY SEE SNOWFALL AMOUNTS AS HIGH AS 3-6 INCHES SATURDAY
THROUGH MONDAY WITH HIGHER AMOUNTS POSSIBLE IN AREAS WHERE LOW-LEVEL
CONVERGENCE IS MOST FOCUSED. FLOW SHIFT WESTWARD BY TUES/WEDS MAKING
LES LESS LIKELY FOR THE COUNTIES IN OUR CWA. ASIDE FROM LES... THE
WEEK LOOKS RATHER DRY FOR MUCH OF THE NORTHLAND.
TEMPERATURE IMPROVEMENT BEGINS TUESDAY AS THE JET STREAM SHIFTS THE
500MB LOW EASTWARD. THE GFS INDICATES NW FLOW TO REMAIN IN PLACE
UNTIL THE FLOW BECOMES QUASI-ZONAL ACROSS THE NORTHLAND BY
THURS/FRI. BY THE END OF THE WEEK TEMPS WILL LIKELY BE CLOSER TO IF
NOT ABOVE CLIMATOLOGICAL NORMALS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1123 AM CST FRI JAN 15 2016
AN AREA OF LOW PRESSURE NEAR CENTRAL LAKE MICHIGAN WILL SHIFT EAST
TOWARDS LAKE HURON TODAY...WHILE ARCTIC HIGH PRESSURE IN CANADA
WILL CONTINUE TO SHIFT SOUTH INTO THE NORTHERN PLAINS AND UPPER
MIDWEST...AND BRING THE NEXT WAVE OF FRIGID AIR.
THERE WILL BE LINGERING IFR/MVFR CONDITIONS ACROSS NE MINNESOTA
AND NW WISCONSIN TODAY...BUT MOST TERMINALS SHOULD SEE A GRADUAL
CLEARING TREND THIS AFTERNOON INTO THIS EVENING. THE EXCEPTION
WILL BE KHYR...WHERE THE MORE HUMID NORTHERLY FLOW FROM LAKE
SUPERIOR WILL MAINTAIN IFR/MVFR CEILINGS THROUGH AT LEAST THE WEE
HOURS OF SATURDAY MORNING. THE WINDS WILL BACK WITH
TIME...BECOMING MORE WNW BY LATER TONIGHT...SO THE LOW CEILINGS AT
KHYR COULD SHIFT TO JUST EAST OF KHYR BEFORE DAWN.
LESS CONFIDENT ABOUT CLOUD COVER LATER TONIGHT AND EARLY SATURDAY.
THE GFS AND HRRR ARE SUGGESTING LOW CLOUD COVER COULD REDEVELOP OR
LINGER INTO THE NIGHT...WHILE THE NAM HAS A CLEARER TREND. LEANED
ON THE NAM SINCE IT SEEMS TO BE FOLLOWING CURRENT TRENDS BETTER.
THERE COULD BE PERIODS OF VERY LIGHT FREEZING DRIZZLE MIXED IN
WITH THE VERY LIGHT SNOW AT KDLH THROUGH THIS AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 17 -10 -3 -17 / 20 0 0 0
INL 7 -17 -7 -22 / 0 0 0 10
BRD 12 -12 -4 -21 / 0 0 0 0
HYR 26 -6 -1 -17 / 40 10 0 10
ASX 26 1 3 -10 / 70 40 20 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST SATURDAY
FOR MNZ010-011-018-019-025-026-033>037.
LS...SMALL CRAFT ADVISORY UNTIL 10 PM CST THIS EVENING FOR LSZ121-
140>148.
&&
$$
UPDATE...GROCHOCINSKI
SHORT TERM...GSF
LONG TERM...MCLOVIN
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1056 PM CST THU JAN 14 2016
.UPDATE:
Issued at 847 PM CST Thu Jan 14 2016
Am in the process of updating the forecast for the rest of the
night and into Friday morning. RAP and HRRR have been backing off
precip for the overnight hours with each successive run. Seeing
some 5-7000 ft ceiling developing over eastern KS and western MO,
but no echos on radar yet. It looks like the RAP is hinting that
the warm advection showers ahead of the front will not be as wide
spread as the moisture convergence/warm advection does not appear
to be as strong as previously forecast. The bulk of the precip now
looks to be associated with the actual low level convergence ahead
of the front and energy aloft with the shortwave. Will be backing
off the areal coverage and moving timing later in the night for
the initial showers, and then bringing likely pops up the I-44
corridor from about 11Z to 15-16Z ahead of the front.
Carney
&&
.SHORT TERM: (Tonight through Friday)
Issued at 330 PM CST Thu Jan 14 2016
Still looking at a quick and light rain event for the area tonight
into Friday morning. Not much has changed except the models are a
tad slower with the trends and onset of precipitation with this
system. The short wave now moving into the Plains will amplify as
it moves into the MS Valley tonight and then exit rather quickly
into the OH Valley on Friday afternoon. Moisture is initially a
bit limited this evening, however low level WAA, large scale
forcing for ascent, and moisture will ramp up overnight and this
should lead to increasing coverage of showers with time, beginning
in southwest MO around mid-evening and spreading/developing into
the CWA after midnight. The precipitation should shut down by
early afternoon across the CWA as the short wave and associated
cold front move east. After the mild day today, it will feel
vastly different on Friday, especially in the afternoon with gusty
west-northwest winds contributing to strong CAA and falling
temperatures in the wake of the front.
Glass
.LONG TERM: (Friday Night through Next Thursday)
Issued at 330 PM CST Thu Jan 14 2016
Surface high pressure builds into the area Friday night into
Saturday and conditions are seasonably cold and relatively calm. A
strong upper vortex/trof will dig from east of Lake Winnipeg on
Saturday through the Great Lakes region Saturday and Saturday
night, carving out a long wave trof over the eastern 2/3rds of
the CONUS which will dominate Sunday-Monday. The height falls and
large scale ascent accompanying the upper system and frontogenesis
with a strong secondary cold surge will contribute to a region of
light snow. The best threat at this time will be centered along
and north of I-70 and a 1-2 inch event is possible. POPs are
probably too low but we con`t to increase them with sucessive
forecasts. Strong high pressure builds into the area Sunday
night into Monday as a very cold air mass, the coldest so far this
winter, settles in and brings a winter grip.
The flow aloft flattens after Monday in the wake of the departing
long wave trof in the east and considerable model variability
ensues in the deterministic and ensemble solutions. The ECMWF has
come around to the GFS with another light snow event centered on
Tuesday, however the system is much weaker. Another precipitation
event appears on tap on Thursday however there are large
differences in many details, especially the thermal structure.
Glass
&&
.AVIATION: (For the 06z TAFs through 06z Friday Night)
Issued at 1036 PM CST Thu Jan 14 2016
An upper level disturbance and cold front will move through our
area late tonight and Friday morning. MVFR cigs will develop and
spread northeastward into the taf sites late tonight, eventually
dropping into the IFR catagory, at least briefly early Friday
morning. A band of light rain will also move into the area late
tonight from southwest MO, mainly impacting the St Louis metro
area Friday morning. A strong swly low level jet will contribute
to LLWS conditions late tonight with swly winds at 1500-2000 feet
in height of 45-50 kts. The rain should shift east of the St Lous
metro area by late morning. Swly surface wind will veer around to
a nwly direction after fropa Friday morning. Post frontal MVFR
cigs will likely continue through the end of the forecast period.
Specifics for KSTL: Light rain along with MVFR cigs will spread
into STL around 12Z Friday. The ceiling will continue to drop
into the IFR catagory Friday morning. The rain should end by late
Friday morning, with the ceiling lifting back up into the MVFR
catagory by early afternoon. S-swly surface wind will veer around
to a nwly direction Friday morning after fropa, and strengthen
becoming gusty in the afternoon. The nwly surface wind will weaken
Friday night.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
852 PM MST SAT JAN 16 2016
.UPDATE...
SNOW AMOUNTS HAVE BEEN LIGHT THUS FAR OVER THE ADVISORY AREA WITH
JUST SMALL DENDRITES FALLING ACROSS THE AREA. SNOW WAS OCCURRING
IN AREA OF WEAK ISENTROPIC LIFT. BAND OF FRONTOGENESIS WAS
FORECAST TO MOVE E INTO CENTRAL AREAS OVERNIGHT THROUGH SUN
MORNING. THIS LIFT SHOULD INCREASE SNOWFALL AMOUNTS ALTHOUGH
DENDRITIC GROWTH DID NOT LOOK AS DEEP ON THE RAP SOUNDINGS AS IT
DID THIS EVENING. Q-VECTOR CONVERGENCE ALSO INCREASES OVERNIGHT
WITH APPROACH OF SHORTWAVE...SEEN ON WATER VAPOR IMAGERY...MOVING
OUT OF THE PACIFIC NW. DUE TO THE ABOVE FACTORS...WILL NOT MAKE
ANY CHANGES TO SNOW AMOUNTS OR THE ADVISORY. DOWNSLOPE FLOW WILL
KEEP THE FOOTHILLS FROM REACHING ADVISORY CRITERIA AS EASTERLY
LOW-LEVEL FLOW WAS RATHER SHALLOW. THE NW FLOW ALOFT WILL KEEP
THE NE BIGHORNS FROM REACHING ADVISORY SNOW AMOUNTS AS WELL.
LOOKING FOR A BITTER COLD NIGHT OVER THE FAR EASTERN ZONES WHERE
SKIES WILL BE CLEAR...DEWPOINTS WILL BE IN THE NEGATIVE TEENS TO
20S AND WINDS WILL BE LIGHT. WILL NOT BE MEETING WIND CHILL
ADVISORY CRITERIA DUE TO THE LIGHT WINDS. ONLY FORECAST CHANGE WAS
TO INCREASE POPS TO 100 PERCENT OVER AREAS S OF KBIL WHERE SNOW
HAS BEEN OCCURRING ALL EVENING. ARTHUR
&&
.SHORT TERM...VALID FOR SUN AND MON...
WATER VAPOR IMAGERY SHOWS COLD UPPER LOW JUST NORTH OF MN...NW
FLOW OVER OUR REGION AND PACIFIC ENERGY MOVING INTO WA/OR. LIGHT
SNOW ACROSS OUR EAST IS FADING AS COLD/DRY AIR PLUNGES OUT OF
CANADA INTO THE NORTHERN PLAINS...AND IN FACT SKIES ARE CLEARING
ACROSS NORTHEAST MT. COLD FRONT HAS BACKED THROUGH BIG TIMBER BUT
IS NOT YET TO LIVINGSTON...THOUGH IT SHOULD BY 00Z. ATTENTION IS
TURNING TO OUR WEST AS PACIFIC SHORTWAVE APPROACHES. BLX RADAR IS
BEGINNING TO FILL WITH WEAK ECHOES TO OUR WEST AND FLURRIES ARE
NOTED IN BILLINGS. SNOW IS OCCURRING ACROSS WESTERN MT THIS
AFTERNOON.
EVERYTHING LOOKS IN LINE FOR A GENERAL 3 TO 5 INCH OVERRUNNING
SNOWFALL FROM TONIGHT THROUGH MIDDAY SUNDAY ACROSS MUCH OF OUR
WEST AND CENTRAL AREAS AND HAVE ALREADY ISSUED WINTER WX
ADVISORIES FOR MUSSELSHELL-YELLOWSTONE-BIG HORN-SHERIDAN COUNTIES
WESTWARD. DENDRITIC LAYER WILL DEEPEN CONSIDERABLY AND THIS WILL
BE KEY IN ALLOWING FOR HIGH SNOW RATIOS W/ THIS EVENT...LIKELY AS
HIGH AS 20:1...YIELDING SEVERAL INCHES DESPITE RELATIVELY WEAK
FORCING AS PACIFIC SHORTWAVE WILL BE SPLITTING AS IT MOVES INTO
THE NORTHERN ROCKIES.
COUPLE AREAS TO WATCH TONIGHT. COLD AIR IS FAIRLY SHALLOW AND
DOWNSLOPE WINDS SHOULD BE SIGNIFICANT ENOUGH TO LIMIT SNOW ACCUMS
ALONG THE BEARTOOTH/RED LODGE FOOTHILLS TONIGHT...IE GREATER
AMOUNTS SHOULD BE FURTHER AWAY FROM THE STEEP TERRAIN. THIS IS
TYPICALLY WHAT TO EXPECT DURING A PACIFIC OVERRUNNING SNOW EVENT.
THE BIGHORN MOUNTAINS ARE ANOTHER AREA OF CONCERN. WEAK FORCING
AND A SHALLOW DENDRITIC LAYER ABOVE MOUNTAIN TOP WILL BE FACTORS
DESPITE THE NWLY MID LEVEL FLOW. WILL KEEP THE BIGHORNS UNDER
ADVISORY CRITERIA BUT THEY SHOULD STILL SEE A FEW INCHES OF
ACCUMULATION...AS WILL OUR WESTERN MOUNTAINS.
PCPN WILL TAPER OFF ALONG OUR WESTERN FOOTHILLS BY EARLY SUNDAY AS
MID LEVEL BAROCLINICITY BEGINS TO SHIFT EAST AND DOWNSLOPE WINDS
DEVELOP. THIS COULD RESULT IN LOCAL BLOWING SNOW ALONG THE
FOOTHILLS. SNOW WILL PERSIST IN CENTRAL PARTS INCLUDING BILLINGS
INTO MIDDAY BEFORE TAPERING OFF COMPLETELY DURING THE AFTERNOON.
TEMPS WILL BE COLDEST IN OUR EAST AND COULD SEE 20 BELOW AT BAKER
TONIGHT. LIVINGSTON REMAINS IN THE MID 30S CURRENTLY BUT SHOULD
PLUMMET TO THE TEENS WITH A SHIFT TO EASTERLY WINDS THIS EVENING.
TEMPS TOMORROW WILL SHOW A SHARP CONTRAST FROM WEST TO EAST...WITH
UPPER 30S AND DOWNSLOPE WINDS ALONG OUR FOOTHILLS AND ONLY SINGLE
DIGITS ALONG THE DAKOTAS BORDER. BELIEVE BILLINGS WILL REMAIN
ENTRENCHED ON THE COLD SIDE OF THE SFC BOUNDARY THROUGH THE DAY
SUNDAY...WITH A BETTER CHANCE OF MODERATION SUNDAY NIGHT AS LEE
SIDE TROF DEEPENS AND SHIFTS EAST. DIFFICULT TEMP FORECAST
TOMORROW NIGHT.
ANOTHER PACIFIC SHORTWAVE WILL MOVE THROUGH THE AREA MONDAY AND
MONDAY NIGHT. THIS SYSTEM WILL BE MUCH WARMER AND COULD BRING A
MIX OF RAIN AND SNOW SHOWERS TO WESTERN LOWER ELEVATIONS...AND
SOME SNOW FOR THE MOUNTAINS. OUR NORTHEAST COULD SEE A LITTLE SNOW
ACCUMULATION PER LINGERING LOW LEVEL COLDER AIR AND EAST WINDS.
SOMETHING TO THINK ABOUT. OTHERWISE WINDS WILL BE GUSTY OVER OUR
WEST ONCE THE COLD AIR RETREATS IN A PACIFIC FLOW REGIME.
JKL
.LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT...
OVERALL THE LONGTERM REMAINS PRETTY MUCH UNCHANGED. THE BIGGEST
CHANGE IS THE DETERMINISTIC GFS IS MUCH MORE AGGRESSIVE WITH THE
THE PACIFIC WAVE WEDNESDAY...DEVELOPING INTO A MUCH DEEPER TROUGH
ACROSS THE NORTHERN ROCKIES. THE ECMWF IS NOT AS AGGRESSIVE AND
EVENT THE GEFS MEAN IS MUCH LESS AGGRESSIVE. FOR NOW HAVE
GENERALLY GONE MORE TOWARDS THE EC/GEFS SOLUTION AND KEPT THINGS
DRIER FOR THE AREA. ALSO WITH THE STRONGER GFS SOLUTION WINDS WERE
NOT AS STRONG THURSDAY. SINCE AM GOING MORE TOWARDS THE EC
SOLUTION WITH POPS AM GOING STRONGER WITH THE WINDS AROUND THE
FOOTHILLS ON THURSDAY.
OTHERWISE...A DRY PATTERN FOR MUCH OF THE AREA. FLOW CONTINUES TO
BE NORTHWEST FLOW...BUT MOST OF THE PACIFIC MOISTURE WILL
PRIMARILY REMAIN WEST OF THE DIVIDE. WHILE MOST OF THE MOISTURE
WILL STAY OUT OF THE AREA...THE MOUNTAINS WILL SEE A CHANCE FOR
SNOW THROUGH THE EXTENDED WITH THE UNSTABLE FLOW. TEMPERATURES
WILL REBOUND NICELY...AND BY THE SECOND HALF OF THE WEEK WILL BE
ABOVE NORMAL. REIMER
&&
.AVIATION...
MVFR CONDITIONS IN LOW CLOUDS AND SNOW WILL BECOME IFR OVERNIGHT
AS SNOW INTENSIFIES. THESE CONDITIONS WILL BE WEST OF LINE FROM
KBIL TO KSHR. EAST OF KBIL...CLOUDS WILL DECREASE AND CONDITIONS
WILL BECOME VFR OVERNIGHT...ALTHOUGH THERE WILL BE LOW CLOUDS AND
MVFR CONDITIONS AT KMLS DURING THE EVENING AND EARLY OVERNIGHT
HOURS. SNOW WILL CONTINUE FROM KBIL AND KSHR WESTWARD SUNDAY
MORNING...BEFORE TAPERING OFF BY EARLY SUNDAY AFTERNOON. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
SUN MON TUE WED THU FRI SAT
-----------------------------------------------------------
BIL 007/019 016/040 026/036 024/039 024/039 029/042 027/039
++/S 12/W 21/B 12/J 11/B 11/N 12/W
LVM 015/037 030/040 027/037 027/039 027/040 031/042 028/037
+3/S 33/W 21/N 22/W 11/N 11/N 23/W
HDN 005/020 011/039 019/035 015/037 016/037 021/039 022/037
++/S 12/W 30/B 12/J 11/B 11/B 01/B
MLS 913/009 901/034 017/032 013/032 017/035 023/039 022/036
11/B 15/J 31/B 01/B 11/B 11/B 01/B
4BQ 907/016 003/038 019/036 012/036 016/036 021/041 019/037
25/S 12/W 41/B 01/B 11/B 11/B 01/B
BHK 921/006 909/026 015/031 011/028 015/033 020/038 018/035
00/U 04/J 41/B 01/B 11/B 11/B 01/B
SHR 009/024 013/041 020/038 018/039 019/041 023/045 021/038
+9/S 12/W 31/B 12/J 11/B 11/B 02/J
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL NOON MST SUNDAY FOR
ZONES 28-40-41-63>65.
WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 PM MST SUNDAY FOR
ZONES 29-34-35-38-39-42-57.
WY...WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 PM MST SUNDAY FOR
ZONE 99.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS GLASGOW MT
1217 PM MST FRI JAN 15 2016
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SUNDAY...
WITH THE CONTINUATION OF SNOW SHOWERS MOVING IN ON NW FLOW INTO
THE CWA, INCREASED POPS ACROSS THE CENTRAL ZONES FOR THIS
AFTERNOON. REST OF FORECAST WAS LEFT UNTOUCHED. TFJ
914 AM UPDATE...
MAIN UPDATE WAS TO RAISE TEMPERATURES FOR TODAY AS THEY WERE
ALREADY REACHED OR EXCEEDED IN SOME PLACES. OTHERWISE, REST OF
FORECAST LOOKED TO BE ON TARGET SO FAR. TFJ
PREVIOUS DISCUSSION...
FORECAST CHALLENGES IN THE SHORT TERM PERIOD WILL FOCUS ON
TEMPERATURES AND THE EXTENT OF THE SCATTERED SNOW
SHOWERS...ESPECIALLY FOR THE SW HALF OF OUR CWA TODAY...THEN COLD
WIND CHILLS LATER THROUGH THE WEEKEND.
CURRENT WATER VAPOR IMAGERY AND 500 MB HEIGHT FIELD SHOWS A
GENERAL NW FLOW ALOFT WITH LIMITED MOISTURE RESULTING IN SOME
SCATTERED SNOW SHOWERS PRIMARILY OVER OUR WESTERN ZONES. IT SEEMS
THAT THE MORE AGGRESSIVE MODEL DEPICTIONS OF PRECIP...SUCH AS THE
NAM AND GFS...HAVE PROVEN TOO AGGRESSIVE OVERNIGHT. LIGHTER
AMOUNTS FROM THE HRRR MODEL ARE MORE REPRESENTATIVE OF ACTUAL AREA
REFLECTIVITIES. WOULD EXPECT NEW SNOWFALL TOTALS TO BE CLOSER TO
AROUND 1 INCH THAN 2 INCHES.
WITH THE ARRIVAL OF THE ARCTIC AIR MASS ON SATURDAY...SCATTERED
SNOW SHOWERS AND FLURRIES WILL BE CLEARED OUT AND REPLACED BY A
MORE CERTAIN WEATHER PATTERN OF CLEARING SKIES AND MUCH COLDER
TEMPERATURES OVER OUR CENTRAL AND NE ZONES AND A BAND
ACCUMULATING SNOW OVER OUR SW ZONES.
SATURDAY NIGHT...WIND CHILL CONCERNS WILL ARISE WITH THE COLDEST
TEMPERATURES AND WINDS AROUND 10 MPH POSSIBLE ESPECIALLY FOR OUR
NE CWA ZONES EXPECTED TO BRING WIND CHILL VALUES BETWEEN 25 AND 40
DEGREES BELOW ZERO. NOT YET CONFIDENT OR CLOSE ENOUGH TO GO WITH
ANY WIND CHILL HEADLINE PRODUCTS BUT NEXT FEW SHIFTS WILL NEED TO
SERIOUSLY CONSIDER THE NEED IF TEMPERATURE AND WIND MODEL TRENDS
CONTINUE IN THIS WAY. BMICKELSON
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...
EXTENDED PERIOD OPENS NEXT WEEK WITH AN ARCTIC LOW OVER THE
NORTHERN GREAT LAKES AND UPPER RIDGE PUSHING THROUGH THE NORTHERN
ROCKIES.. ARCTIC HIGH MOVING OUT OF THE NORTHERN PLAINS WILL HAVE
LEFT BEHIND A COLD AIRMASS ACROSS MOST OF NORTHEAST MONTANA FOR
MONDAY. AS A SHORTWAVE PUSHES THROUGH THE RIDGE AND ACROSS THE
NORTHERN ROCKIES ON MONDAY...MOISTURE WILL SPREAD OVER THE COLD
AIRMASS...BRINGING LIGHT SNOW INTO EASTERN MONTANA.
REMAINDER OF THE WEEK FEATURES MORE UNCERTAINTY WITH A SERIES OF
PACIFIC OR ARCTIC SHORTWAVES DEPENDING ON THE MODEL SOLUTION.
MODELS TRENDING TOWARD WARMING ALOFT BY THE END OF THE WEEK BUT
GIVEN THE PERSISTENCE OF THE COLD AIR MASS OVER THE REGION WILL
KEEP TEMPERATURES BELOW CLIMO FOR MOST OF THE PERIOD. EBERT
&&
.AVIATION...
MVFR TO IFR CIGS WILL PREVAIL THROUGH THE DAY. REDUCED VSBYS IN
SNOW SHOWERS AND PATCHY FREEZING FOG WILL ALSO CONTINUE AT TIMES
THROUGH THE DAY. NORTH WINDS WILL CONTINUE AT AROUND 5 TO 10 KTS
INTO THIS AFTERNOON. MALIAWCO
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS GLASGOW MT
914 AM MST FRI JAN 15 2016
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SUNDAY...
MAIN UPDATE WAS TO RAISE TEMPERATURES FOR TODAY AS THEY WERE ALREADY
REACHED OR EXCEEDED IN SOME PLACES. OTHERWISE, REST OF FORECAST
LOOKED TO BE ON TARGET SO FAR. TFJ
PREVIOUS DISCUSSION...
FORECAST CHALLENGES IN THE SHORT TERM PERIOD WILL FOCUS ON
TEMPERATURES AND THE EXTENT OF THE SCATTERED SNOW
SHOWERS...ESPECIALLY FOR THE SW HALF OF OUR CWA TODAY...THEN COLD
WIND CHILLS LATER THROUGH THE WEEKEND.
CURRENT WATER VAPOR IMAGERY AND 500 MB HEIGHT FIELD SHOWS A
GENERAL NW FLOW ALOFT WITH LIMITED MOISTURE RESULTING IN SOME
SCATTERED SNOW SHOWERS PRIMARILY OVER OUR WESTERN ZONES. IT SEEMS
THAT THE MORE AGGRESSIVE MODEL DEPICTIONS OF PRECIP...SUCH AS THE
NAM AND GFS...HAVE PROVEN TOO AGGRESSIVE OVERNIGHT. LIGHTER
AMOUNTS FROM THE HRRR MODEL ARE MORE REPRESENTATIVE OF ACTUAL AREA
REFLECTIVITIES. WOULD EXPECT NEW SNOWFALL TOTALS TO BE CLOSER TO
AROUND 1 INCH THAN 2 INCHES.
WITH THE ARRIVAL OF THE ARCTIC AIR MASS ON SATURDAY...SCATTERED
SNOW SHOWERS AND FLURRIES WILL BE CLEARED OUT AND REPLACED BY A
MORE CERTAIN WEATHER PATTERN OF CLEARING SKIES AND MUCH COLDER
TEMPERATURES OVER OUR CENTRAL AND NE ZONES AND A BAND
ACCUMULATING SNOW OVER OUR SW ZONES.
SATURDAY NIGHT...WIND CHILL CONCERNS WILL ARISE WITH THE COLDEST
TEMPERATURES AND WINDS AROUND 10 MPH POSSIBLE ESPECIALLY FOR OUR
NE CWA ZONES EXPECTED TO BRING WIND CHILL VALUES BETWEEN 25 AND 40
DEGREES BELOW ZERO. NOT YET CONFIDENT OR CLOSE ENOUGH TO GO WITH
ANY WIND CHILL HEADLINE PRODUCTS BUT NEXT FEW SHIFTS WILL NEED TO
SERIOUSLY CONSIDER THE NEED IF TEMPERATURE AND WIND MODEL TRENDS
CONTINUE IN THIS WAY. BMICKELSON
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...
EXTENDED PERIOD OPENS NEXT WEEK WITH AN ARCTIC LOW OVER THE
NORTHERN GREAT LAKES AND UPPER RIDGE PUSHING THROUGH THE NORTHERN
ROCKIES.. ARCTIC HIGH MOVING OUT OF THE NORTHERN PLAINS WILL HAVE
LEFT BEHIND A COLD AIRMASS ACROSS MOST OF NORTHEAST MONTANA FOR
MONDAY. AS A SHORTWAVE PUSHES THROUGH THE RIDGE AND ACROSS THE
NORTHERN ROCKIES ON MONDAY...MOISTURE WILL SPREAD OVER THE COLD
AIRMASS...BRINGING LIGHT SNOW INTO EASTERN MONTANA.
REMAINDER OF THE WEEK FEATURES MORE UNCERTAINTY WITH A SERIES OF
PACIFIC OR ARCTIC SHORTWAVES DEPENDING ON THE MODEL SOLUTION.
MODELS TRENDING TOWARD WARMING ALOFT BY THE END OF THE WEEK BUT
GIVEN THE PERSISTENCE OF THE COLD AIR MASS OVER THE REGION WILL
KEEP TEMPERATURES BELOW CLIMO FOR MOST OF THE PERIOD. EBERT
&&
.AVIATION...
MVFR TO IFR CIGS WILL PREVAIL THROUGH THE DAY. REDUCED VSBYS IN
SNOW SHOWERS AND PATCHY FREEZING FOG WILL ALSO CONTINUE AT TIMES
THROUGH THE DAY. NORTH WINDS WILL CONTINUE AT AROUND 5 TO 10 KTS
INTO THIS AFTERNOON. MALIAWCO
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS GLASGOW MT
326 AM MST FRI JAN 15 2016
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SUNDAY...
FORECAST CHALLENGES IN THE SHORT TERM PERIOD WILL FOCUS ON
TEMPERATURES AND THE EXTENT OF THE SCATTERED SNOW
SHOWERS...ESPECIALLY FOR THE SW HALF OF OUR CWA TODAY...THEN COLD
WIND CHILLS LATER THROUGH THE WEEKEND.
CURRENT WATER VAPOR IMAGERY AND 500 MB HEIGHT FIELD SHOWS A
GENERAL NW FLOW ALOFT WITH LIMITED MOISTURE RESULTING IN SOME
SCATTERED SNOW SHOWERS PRIMARILY OVER OUR WESTERN ZONES. IT SEEMS
THAT THE MORE AGRESSIVE MODEL DEPICTIONS OF PRECIP...SUCH AS THE
NAM AND GFS...HAVE PROVEN TOO AGRESSIVE OVERNIGHT. LIGHTER
AMOUNTS FROM THE HRRR MODEL ARE MORE REPRESENTATIVE OF ACTUAL AREA
REFLECTIVITIES. WOULD EXPECT NEW SNOWFALL TOTALS TO BE CLOSER TO
AROUND 1 INCH THAN 2 INCHES.
WITH THE ARRIVAL OF THE ARCTIC AIR MASS ON SATURDAY...SCATTERED
SNOW SHOWERS AND FLURRIES WILL BE CLEARED OUT AND REPLACED BY A
MORE CERTAIN WEATHER PATTERN OF CLEARING SKIES AND MUCH COLDER
TEMPERATURES OVER OUR CENTRAL AND NE ZONES AND A BAND
ACCUMULATING SNOW OVER OUR SW ZONES.
SATURDAY NIGHT...WIND CHILL CONCERNS WILL ARISE WITH THE COLDEST
TEMPERATURES AND WINDS AROUND 10 MPH POSSIBLE ESPECIALLY FOR OUR
NE CWA ZONES EXPECTED TO BRING WIND CHILL VALUES BETWEEN 25 AND 40
DEGREES BELOW ZERO. NOT YET CONFIDENT OR CLOSE ENOUGH TO GO WITH
ANY WIND CHILL HEADLINE PRODUCTS BUT NEXT FEW SHIFTS WILL NEED TO
SERIOUSLY CONSIDER THE NEED IF TEMPERATURE AND WIND MODEL TRENDS
CONTINUE IN THIS WAY. BMICKELSON
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...
EXTENDED PERIOD OPENS NEXT WEEK WITH AN ARCTIC LOW OVER THE
NORTHERN GREAT LAKES AND UPPER RIDGE PUSHING THROUGH THE NORTHERN
ROCKIES.. ARCTIC HIGH MOVING OUT OF THE NORTHERN PLAINS WILL HAVE
LEFT BEHIND A COLD AIR MASS ACROSS MOST OF NORTHEAST MONTANA FOR
MONDAY. AS A SHORTWAVE PUSHES THROUGH THE RIDGE AND ACROSS THE
NORTHERN ROCKIES ON MONDAY...MOISTURE WILL SPREAD OVER THE COLD
AIR MASS...BRINGING LIGHT SNOW INTO EASTERN MONTANA.
REMAINDER OF THE WEEK FEATURES MORE UNCERTAINTY WITH A SERIES OF
PACIFIC OR ARCTIC SHORTWAVES DEPENDING ON THE MODEL SOLUTION.
MODELS TRENDING TOWARD WARMING ALOFT BY THE END OF THE WEEK BUT
GIVEN THE PERSISTENCE OF THE COLD AIR MASS OVER THE REGION WILL
KEEP TEMPERATURES BELOW CLIMO FOR MOST OF THE PERIOD. EBERT
&&
.AVIATION...
MVFR CEILINGS EXPECTED TO LINGER THROUGH TODAY. VISIBILITY
REDUCTIONS ARE ALSO POSSIBLE WITH FOG OR SNOW SHOWERS THROUGH THE
DAY.
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
535 PM CST SAT JAN 16 2016
.SYNOPSIS...
ISSUED AT 322 PM CST SAT JAN 16 2016
H5 ANALYSIS FROM THIS MORNING HAS A CLOSED LOW NORTHEAST
OF WINNIPEG MANITOBA WITH A TROUGH OF LOW PRESSURE ACROSS THE UPPER
MIDWEST INTO THE MISSOURI AND MID MISSISSIPPI VALLEY. FURTHER
WEST...A RIDGE EXTENDED UP THE WEST COAST OF THE CONUS INTO BRITISH
COLUMBIA...WHILE WEST OF THE RIDGE...A CLOSED LOW WAS PRESENT JUST
SOUTH OF THE ALEUTIANS. HT FALLS OF 50 TO 100 METERS WERE NOTED FROM
MINNESOTA...EAST INTO WISCONSIN AND MICHIGAN...SO THE LOW IS
EXPECTED TO TRACK TO THE SOUTHEAST OVER THE NEXT 12 TO 24 HOURS. AT
THE SURFACE...AN ARCTIC COLD FRONT HAS NOSED INTO NORTHERN NEBRASKA
TODAY AND WAS ROUGHLY ORIENTED ALONG AND NORTH OF HIGHWAY 2 AS OF
MID AFTERNOON. FLURRIES WERE BEING REPORTED BEHIND THE FRONT OVER
NORTH CENTRAL NEBRASKA WITH VISBYS GENERALLY IN THE 6 TO 10 MILE
RANGE. TEMPERATURES VARIED WIDELY THIS AFTERNOON ACROSS WESTERN AND
NORTH CENTRAL NEBRASKA. READINGS WERE IN THE SINGLE DIGITS OVER FAR
NORTHERN AREAS...WHILE READINGS HAVE REACHED THE MID AND UPPER 30S
OVER FAR SWRN NEBRASKA.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 322 PM CST SAT JAN 16 2016
THE MAIN FORECAST CHALLENGES THROUGH SUNDAY ARE TEMPERATURES AND
SNOW CHANCES. AN ARCTIC COLD FRONT WILL CONTINUE DROPPING SOUTH
ACROSS THE FORECAST AREA...BRINGING SOME OF THE COLDEST AIR OF THE
SEASON.
THIS EVENING...AREAS OF LIGHT SNOW WILL CONTINUE ACROSS NORTH
CENTRAL NEBRASKA...RESULTING IN LITTLE ACCUMULATION. NAM AND HRRR
FORECAST SOUNDINGS INDICATE SUFFICIENT MOISTURE FROM THE NEAR SFC
LAYER TO TO ABOUT 700HPA...BUT LIFT IS MARGINAL AND GENERALLY NOT
WITHIN THE DGZ. THROUGH EARLY AFTERNOON...COVERAGE OF THE SNOW
SHOWERS WAS WIDESPREAD ENOUGH TO WARRANT LIKELY POPS INTO THE
EVENING...BUT LIMITED QPF TO JUST A COUPLE HUNDREDTHS. WITH SFC
TEMPS IN THE TEENS AND AROUND -15C AT 850HPA...WENT HIGH ON THE
SLR...GENERALLY AROUND 20 TO 1. BRIEF PERIODS OF FLUFFY SNOW MAY
PILE UP TO A HALF INCH OR SO AFTER SUNSET.
OVERNIGHT...THE -SN OVER NORTH CENTRAL NEBRASKA MOVES EAST BUT THE
NEXT ROUND MOVES INTO THE PANHANDLE. MOST MODELS SHOW A LARGE AREA
OF MID LEVEL FRONTOGENESIS ACROSS THE FORECAST AREA. CONSIDERABLE
DRYING TAKES PLACE NORTH CENTRAL...BUT MOISTURE FILLS IN ACROSS THE
WEST. THE NAM INDICATES SOME ISENTROPIC UPGLIDE AT 290K IN THE
PANHANDLE AROUND 12Z...GENERALLY OUT OF THE FORECAST AREA...BUT
STEERING WINDS AND MID LEVEL FLOW TAKE ANY SNOW THAT DEVELOPS INTO
THE WESTERN SANDHILLS AND SOUTHWEST NEBRASKA. THE SNOW WILL BE LIGHT
AND NOT EXPECTING MUCH IN TERMS OF MOISTURE...BUT VERY COLD TEMPS
AGAIN LEAD TO A HIGHER THAN CLIMO SLR. FOR MIN TEMPS...DID NOT
ADJUST TOO MUCH FROM PREVIOUS FORECAST EXCEPT JUST A LITTLE TOWARD
ECM GUIDANCE. SUBZERO LOWS ARE FORECAST FOR MOST AREAS NORTH OF HWY
2. WENT WITH A GENERAL BLEND FOR WIND...RESULTING IN SFC SPEEDS
AROUND 10 KTS FOR THE EASTERN THIRD OF THE CWA THROUGHOUT THE NIGHT.
HOISTED WIND CHILL ADVISORY FAR NORTH CENTRAL WHERE VALUES OF -20 TO
-25 ARE EXPECTED FOR A FEW HOURS.
SUNDAY...KEPT -SN MENTION FAR WEST THROUGH THE DAY AS THE NAM SHOWS
CONTINUED MOISTURE AND BETTER ISENTROPIC LIFT IN THE LOWER
LEVELS...GENERALLY FROM KCDR TO KIML. THE RIGHT REAR PORTION OF THE
100+ KT JET STREAK AT 250HPA LIES ACROSS NORTHEAST NEBRASKA FROM 12
TO 18Z...PROVIDING UPPER TROPOSPHERIC SUPPORT. HOWEVER...QPF WILL BE
RATHER LIGHT AS THE BEST LIFT IS OUTSIDE THE SATURATED LAYER AND
GROWTH ZONE. FOR MAX TEMPS...HUGGED THE ECM ACROSS THE SOUTH AND
GENERALLY WENT BELOW GUIDANCE NORTH CENTRAL. CLOUD COVER WILL
DECREASE THROUGHOUT THE DAY INVOF KONL AND KANW...BUT 850HPA TEMPS
WILL STAY NEAR -15C WITH NORTHWEST FLOW.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 322 PM CST SAT JAN 16 2016
MID RANGE...SUNDAY NIGHT THROUGH TUESDAY...THE MAIN FORECAST
CHALLENGES IN THE MID RANGE CENTER ON SNOW CHANCES SUNDAY
EVENING...AS WELL AS MONDAY NIGHT INTO TUESDAY. FOR SUNDAY
EVENING...ARCTIC HIGH PRESSURE WILL BUILD INTO EASTERN
NEBRASKA...FORCING THE ARCTIC AIR MASS WEST INTO THE PANHANDLE AND
WESTERN NEBRASKA. A NICE COLD FRONT IS PRESENT AT THE SURFACE AND
ALOFT AT H700 SUNDAY EVENING. MID LEVEL FRONTOGENESIS IS ENHANCED IN
OVER THE EASTERN PANHANDLE AND WESTERN NEBRASKA SUNDAY EVENING WITH
WEAK LIFT NOTED. AT THE SAME TIME...BOTH THE GFS AND NAM SOLNS
INDICATE A DECENT AMOUNT OF MOISTURE IN THE H850-H700 MOIST LAYER
SUNDAY EVENING...COLLOCATED WITH THE AREA OF WEAK LIFT AND WITHIN THE
DENDRITIC ZONE. WITH QPF/S GENERALLY A HUNDREDTH OF AN INCH OR
LESS...WILL LIMIT MENTION OF SNOW TO FLURRIES ATTM. BY
MIDNIGHT...THE AREA OF MOISTURE IN THE H700 TO H850 LAYER SLIDES
SOUTHEAST OF THE FORECAST AREA...AND HAVE ENDED THE MENTION OF
FLURRIES AT 06Z MONDAY. ON MONDAY...SURFACE HIGH PRESSURE WILL SLIDE
SOUTHEAST INTO MISSOURI. SOUTHERLY AND SOUTHEASTERLY WINDS WILL
INCREASE ON THE BACK SIDE OF THE HIGH...RECYCLING ARCTIC AIR INTO
THE EASTERN HALF OF THE FORECAST AREA. HIGHS WILL BE IN THE 20S TO
AROUND 30 GENERALLY EAST OF A LINE FROM MERRIMAN TO NORTH PLATTE.
WEST OF THIS LINE...WINDS WILL HAVE A MORE WESTERLY COMPONENT...SO
HIGHS WILL REACH THE MID AND UPPER 30S. ON MONDAY NIGHT INTO
TUESDAY...A SECONDARY SHOT OF PCPN WILL IMPACT THE NORTHERN AND
PORTIONS OF THE CENTRAL PLAINS. ON MONDAY EVENING A H7 SHORTWAVE
TROUGH...WILL EMERGE ONTO THE PLAINS FROM THE NORTHERN ROCKIES. AS
THIS APPROACHES THE BLACK HILLS...DECENT MID LEVEL WARM AIR
ADVECTION WILL COMMENCE OVER CENTRAL AND EASTERN SOUTH DAKOTA...AS
WELL AS NORTHERN NEBRASKA MONDAY NIGHT INTO TUESDAY MORNING.
MOISTURE AND LIFT ARE FAVORABLE IN THE DENDRITIC LAYER ACROSS
NORTHERN NEBRASKA AND SRN SD...AND THE NAM AND GFS MODEL SOLUTIONS
GENERATE A NICE BAND OF LIGHT PRECIPITATION OVER NORTHERN NEBRASKA
MONDAY NIGHT. A BLEND OF THE GFS AND NAM SOLNS...YIELDS QPFS OF A 5
TO 15 HUNDREDTHS...WITH THERMAL PROFILES INDICATIVE OF ALL SNOW.
WITH TEMPS IN THE TEENS AND 20S MONDAY NIGHT INTO TUES
MORNING...HAVE OPTED FOR A 12 TO 1 SNOW TO WATER RATIO...WHICH
AGREES WITH THE LATEST NAM COBB OUTPUT. THIS YIELDS A SWATH OF 1 TO
2 INCHES OF SNOW ALONG AND NORTH OF A CODY TO ERICSON LINE. SOUTH OF
THIS LINE...LITTLE OR NO SNOW ACCUMULATION IS ANTICIPATED. SUPPORT
FOR PCPN WILL EXIT THE FORECAST AREA TUESDAY AFTERNOON. HIGHS WILL
RANGE FROM THE MID 20S IN THE EAST DUE TO RESIDUAL CLOUD COVER FROM
THE EXITING SNOWFALL...TO THE LOWER 40S IN FAR SWRN NEBRASKA.
LONG RANGE...TUESDAY NIGHT THROUGH SATURDAY...A BENIGN WEATHER
PATTERN WILL SET IN BEHIND THE EXITING DISTURBANCE...WITH A POSSIBLE
THREAT FOR PCPN DURING THE WEDNESDAY NIGHT PERIOD. BOTH THE GFS AND
ECMWF SOLNS THIS MORNING LIFT A TROUGH OF LOW PRESSURE ALOFT ACROSS
THE CENTRAL PLAINS WEDNESDAY NIGHT. AS WAS THE CASE WITH THE PVS
ECMWF SOLN...THIS FEATURE TRACKS EAST SOUTHEAST FROM COLORADO INTO
SRN KANSAS INTO OKLAHOMA. THE GFS SOLN LIFTS THIS FEATURE EAST INTO
NEBRASKA...WHERE IT THEN TURNS SOUTHEAST INTO THE OZARKS. THIS LATEST
GFS SOLN IS A NEW WRINKLE TO THE GFS SOLN FROM LAST NIGHT AND IS NOT
REAL CONSISTENT WITH ITS PVS RUN. THE ECMWF HAS MORE RUN TO RUN
CONSISTENCY AND REMAINS DRY...SO WILL STEER THE FORECAST IN THAT
DIRECTION. BEYOND MIDWEEK...RIDGING ALOFT BUILDS INTO THE CENTRAL
CONUS. HIGHS WILL TREND UPWARD FROM THE 30S/40S ON THURSDAY...TO THE
40S/LOWER 50S FOR FRIDAY AND SATURDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 534 PM CST SAT JAN 16 2016
THE AREA OF SNOW AND MVFR/LOCAL IFR CIGS ACROSS NCNTL NEB SHOULD
MOVE SOUTH-SOUTHWEST TONIGHT AND THROUGH SWRN NEB 12Z-15Z SUNDAY.
THE RAP MODEL SUGGESTS MVFR CIGS COULD STILL BE ACROSS THE
PANHANDLE AND FAR SWRN AT 16Z. THE NAM AND SREF THEN LIFT MVFR
CIGS NORTH ACROSS THE PANHANDLE SUNDAY AFTERNOON. THE MODELS SHOW
THE POTENTIAL FOR FLURRIES SUNDAY AFTN ACROSS WRN NEB.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 3 AM CST /2 AM MST/ TO NOON CST /11 AM
MST/ SUNDAY FOR NEZ005>010-028-029.
&&
$$
SYNOPSIS...BUTTLER
SHORT TERM...SNIVELY
LONG TERM...BUTTLER
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1025 AM EST FRI JAN 15 2016
.SYNOPSIS...A DEVELOPING LOW PRESSURE SYSTEM WILL TRACK FROM THE
GULF COAST AND UP THE SOUTHEAST AND NC COAST THROUGH
TONIGHT. A DRY COLD FRONT WILL CROSS THE AREA ON SATURDAY.
AN UPPER DISTURBANCE WILL CROSS THE AREA EARLY SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1025 AM FRIDAY...
A SOUTHERN STREAM SHORTWAVE IN SOUTHWESTERLY FLOW ALOFT AND ITS
ASSOCIATED 1002MB...BUT DEEPENING... SURFACE LOW WILL TRACK
NORTHEAST ACROSS THE AREA TODAY. STRONG FORCING FOR ASCENT...DCVA
AND WARM ADVECTION...WILL OVERSPREAD THE AREA THROUGH THIS
AFTERNOON...WITH WIDESPREAD RAINFALL ALREADY ON THE DOORSTEP OF THE
SOUTHERN PIEDMONT AS OF 10AM. MODELS ARE FINALLY CONVERGING ON THE
SURFACE LOW TRACK BEING THROUGH THE COASTAL PLAIN THIS EVENING...OR
MORE SPECIFICALLY CLIPPING SAMPSON COUNTY AROUND 00Z. MODELS
INDICATE SOME VERY WEAK MUCAPE IN THE COASTAL PLAIN WITH THE INLAND
PENETRATION OF THE WARM FRONT LATE THIS AFTERNOON...BUT IT IS STILL
MOSTLY ELEVATED AND THE SEVERE THREAT STILL LOOKS TO BE CONFINED TO
THE COAST DESPITE SUFFICIENT SHEAR THROUGHOUT THE COLUMN. HALF AN
INCH TO AN INCH OF QPF STILL IS STILL EXPECTED...BUT THERE IS SOME
UNCERTAINTY IN THE DISTRIBUTION. HIGH RES GUIDANCE SEEMS TO BE
LATCHING ONTO A TREND THE GFS HAS BEEN SHOWING WITH HEAVIER AMOUNTS
AROUND AN INCH IN THE WESTERN PIEDMONT (IN CLOSER PROXIMITY TO THE
TRACK OF THE MID-LEVEL LOW AND NORTHERN STREAM WAVE PASSING TO OUT
NORTHWEST) AND ALSO EAST OF I-95 (NEAR AND EAST OF THE SURFACE LOW).
ADD IN A POSSIBLE GRAVITY WAVE NOTED IN SURFACE OBS IN SOUTHWEST
GEORGIA THIS MORNING...WHICH MAY BE A PART OF WHY THE HRRR SHOWS A
RAPID SPLIT IF QPF WITH NORTHERN EXTENT THIS AFTERNOON. HIGHS WILL
RANGE FROM MID 40S NW TO MID 50S SE.
CLOUDS WILL GIVE WAY TO CLEARING LATE TONIGHT/SATURDAY
MORNING WITH LOWS IN THE MID 30S NORTHWEST TO LOWER 40S SE.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 255 AM FRIDAY...
SATURDAY: AS THE INLAND LOW OVER THE EASTERN GREAT LAKES MOVES INTO
THE SOUTHEAST CANADA...IT WILL DRAG A DRY COLD FRONT THROUGH THE
AREA SATURDAY AFTERNOON/EVENING. LATE ONSET OF CAA WILL RESULT IN
MILDISH TEMPERATURES ACROSS CENTRAL ON SATURDAY RANGING FROM LOWER
50S NW PIEDMONT TO UPPER 50S ACROSS THE SOUTHEAST.
SATURDAY NIGHT: THE CLOSED UPPER LEVEL LOW THAT TRACKED INLAND OVER
THE PACIFIC NORTHWEST LAST NIGHT WILL CONTINUE TO DEVOLVE INTO AN
OPEN WAVE AS IT DROPS SOUTHEAST ACROSS THE SOUTHERN ROCKIES TONIGHT
AND THEN OVER THE SOUTHERN PLAINS AND INTO CENTRAL GULF COAST REGION
BY SATURDAY NIGHT. MODELS HAVE COME INTO BETTER AGREEMENT WITH A
SUPPRESSED SOUTHERN STREAM SURFACE CYCLOGENESIS OVER THE GULF/DEEP
SOUTH WITH LITTLE TO PRECIP EXPECTED FROM THIS SYSTEM.
INSTEAD...CENTRAL NC COULD SEE SOME VERY LIGHT PRECIP ACROSS THE
AREA LATE SATURDAY NIGHT/SUNDAY MORNING AS NORTHERN STREAM SHORTWAVE
APPROACHES THE AREA FROM THE WEST. GIVEN FAVORABLE NOCTURNAL TIMING
AND MODEST CAA FROM EARLIER COLD FRONTAL PASSAGE SATURDAY
AFTERNOON...COULD SEE A BRIEF PERIOD OF LIGHT RAIN AND POSSIBLY EVEN
LIGHT RAIN OR SNOW ACROSS THE FAR NW PIEDMONT WHERE MODELS SHOW
SURFACE WET-BULBS AROUND FREEZING. AT THIS TIME PRECIP AMOUNTS ARE
TOO LIGHT AND TEMPERATURE PROFILES ARE MARGINALLY COLD ENOUGH TO
SUPPORT MUCH MORE THAN A "GEE WHIZ" SIGHTING OF SNOW. LOWS IN THE
LOWER 30S NW PIEDMONT TO UPPER 30S SOUTHEAST.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 230 AM FRIDAY...
SUNDAY AND SUNDAY NIGHT: THE MEDIUM RANGE MODELS ARE COMING INTO
BETTER AGREEMENT ON HOW THEY HANDLE THE INTERACTION BETWEEN THE
UPPER LEVEL NORTHERN STREAM SHORTWAVE TROUGH MOVING ACROSS THE OH/TN
VALLEY AND INTO THE MID ATLANTIC AND A SOUTHERN STREAM LOW THAT
DEVELOPS OVER THE GULF OF MEXICO. BOTH THE ECMWF AND GFS BRING THE
SOUTHERN STREAM LOW ACROSS THE GULF COAST STATES AND OFF THE SE U.S.
ATLANTIC COAST SUNDAY...KEEPING THE PRECIPITATION...ALL LIQUID...
ALONG AND EAST OF US-1. THE SHORTWAVE HOWEVER MAY GENERATE ITS OWN
PRECIPITATION...WHICH COULD BE NON-LIQUID OR A RAIN/SNOW MIX. THE
PRECIP...REGARDLESS OF TYPE...WILL LIKELY ALL OCCUR BETWEEN 09Z AND
15Z SUNDAY...WITH SOME RAIN LINGERING ACROSS THE FAR EAST INTO THE
EARLY AFTERNOON...AND RESULT IN LITTLE ACCUMULATION. DO NOT EXPECT
ANY SIGNIFICANT IMPACTS AT THIS TIME. HIGHS IN THE MID 40S EXPECTED.
THE COLD SURFACE HIGH WILL START BUILDING INTO THE REGION SUNDAY
NIGHT...WITH CLEARING SKIES BUT WINDS STAYING UP AROUND 5 MPH. AS A
RESULT...LOWS WILL BE COOLER THAN PREVIOUS NIGHTS...LOW 20S NW TO
UPPER 20S SE...FEELING MORE LIKE MID TEENS NW TO MID 20S SE AROUND
DAYBREAK MONDAY.
MONDAY AND TUESDAY: THIS PERIOD IS EXPECTED TO BE COLD AND DRY AS
CANADIAN HIGH PRESSURE BUILDS IN AT THE SURFACE. AS THE UPPER LEVEL
TROUGH PROGRESSES THROUGH THE REGION THE FLOW ALOFT WILL GRADUALLY
BECOME MORE NWRLY. HIGHS MON AND TUE WILL BE FAIRLY STEADY ACROSS
THE NORTH...LOW TO MID 30S...WITH MID 30S TO AROUND 40 DEGREES SOUTH.
LOWS SHOULD BOTTOM OUT MON NIGHT...MID TEENS NW TO LOW 20S SE...
INCREASING A FEW DEGREES TUE NIGHT...LOW TO MID 20S. CURRENT
APPARENT TEMPERATURES TUESDAY MORNING RANGE FROM 10 DEGREES NW TO
MID TEENS SE.
WEDNESDAY AND THURSDAY: TEMPS WILL MODERATE WED AND THU...WITH HIGHS
BACK INTO THE 40S AND LOWS INCREASING FROM THE MID TO UPPER 20S WED
NIGHT TO UPPER 20S TO LOW 30S THU NIGHT. SIGNIFICANT DIFFERENCES IN
THE MEDIUM RANGE MODELS FOR MID TO LATE WEEK YIELD LOW FORECAST
CONFIDENCE...BUT FOR NOW THE FORECAST APPEARS TO BE DRY.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 705 AM FRIDAY...
24 HOUR TAF PERIOD: VFR CONDITIONS THIS WILL GIVE WAY TO WIDESPREAD
IFR TO LIFR CONDITIONS IN RAIN THIS AFTERNOON AND EVENING.
A DEVELOPING AREA OF LOW PRESSURE ALONG THE NORTHERN GULF OF MEXICO
WILL TRACK NEWD THROUGH THE SOUTHEAST TODAY AND THEN ACROSS NORTH
CAROLINA THIS EVENING...BEFORE MOVING UP THE MID-ATLANTIC ON
SATURDAY.
RAIN WILL SPREAD SW TO NE INTO THE AREA LATE THIS MORNING THROUGH
THE EVENING WITH CEILINGS DETERIORATING TO IFR AND POSSIBLY LIFR INTO.
RAIN WILL BE MODERATE TO HEAVY AT TIMES...SO EXPECT SIGNIFICANT
REDUCTION IN VISIBILITIES AS WELL. RAIN SHOULD TAPER OFF FROM SW TO
NE BETWEEN 00Z TO 06Z...WITH VFR CONDITIONS RETURNING SATURDAY
MORNING.
OUTLOOK: AN UPPER LEVEL DISTURBANCE MOVING THROUGH THE AREA LATE
SATURDAY/SUNDAY MORNING COULD BRING SOME MVFR CEILINGS ACROSS THE
AREA ALONG WITH A BRIEF PERIOD OF RAIN/SNOW MIX. VFR CONDITIONS WILL
THEN DOMINATE EARLY TO MID NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...CBL/22
SHORT TERM...CBL
LONG TERM...KC
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
5 AM EST FRI JAN 15 2016
.SYNOPSIS...A DEVELOPING LOW PRESSURE SYSTEM WILL TRACK FROM THE
GULF COAST AND UP THE SOUTHEAST AND NC COAST THROUGH
TONIGHT. A DRY COLD FRONT WILL CROSS THE AREA ON SATURDAY.
AN UPPER DISTURBANCE WILL CROSS THE AREA EARLY SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1025 AM FRIDAY...
A SOUTHERN STREAM SHORTWAVE IN SOUTHWESTERLY FLOW ALOFT AND ITS
ASSOCIATED 1002MB...BUT DEEPENING... SURFACE LOW WILL TRACK
NORTHEAST ACROSS THE AREA TODAY. STRONG FORCING FOR ASCENT...DCVA
AND WARM ADVECTION...WILL OVERSPREAD THE AREA THROUGH THIS
AFTERNOON...WITH WIDESPREAD RAINFALL ALREADY ON THE DOORSTEP OF THE
SOUTHERN PIEDMONT AS OF 10AM. MODELS ARE FINALLY CONVERGING ON THE
SURFACE LOW TRACK BEING THROUGH THE COASTAL PLAIN THIS EVENING...OR
MORE SPECIFICALLY CLIPPING SAMPSON COUNTY AROUND 00Z. MODELS
INDICATE SOME VERY WEAK MUCAPE IN THE COASTAL PLAIN WITH THE INLAND
PENETRATION OF THE WARM FRONT LATE THIS AFTERNOON...BUT IT IS STILL
MOSTLY ELEVATED AND THE SEVERE THREAT STILL LOOKS TO BE CONFINED TO
THE COAST DESPITE SUFFICIENT SHEAR THROUGHOUT THE COLUMN. HALF AN
INCH TO AN INCH OF QPF STILL IS STILL EXPECTED...BUT THERE IS SOME
UNCERTAINTY IN THE DISTRIBUTION. HIGH RES GUIDANCE SEEMS TO BE
LATCHING ONTO A TREND THE GFS HAS BEEN SHOWING WITH HEAVIER AMOUNTS
AROUND AN INCH IN THE WESTERN PIEDMONT (IN CLOSER PROXIMITY TO THE
TRACK OF THE MID-LEVEL LOW AND NORTHERN STREAM WAVE PASSING TO OUT
NORTHWEST) AND ALSO EAST OF I-95 (NEAR AND EAST OF THE SURFACE LOW).
ADD IN A POSSIBLE GRAVITY WAVE NOTED IN SURFACE OBS IN SOUTHWEST
GEORGIA THIS MORNING...WHICH MAY BE A PART OF WHY THE HRRR SHOWS A
RAPID SPLIT IF QPF WITH NORTHERN EXTENT THIS AFTERNOON. HIGHS WILL
RANGE FROM MID 40S NW TO MID 50S SE.
CLOUDS WILL GIVE WAY TO CLEARING LATE TONIGHT/SATURDAY
MORNING WITH LOWS IN THE MID 30S NORTHWEST TO LOWER 40S SE.
&&
.SHORT TERM /SATURDAY AND SATURDAY NIGHT/...
AS OF 255 AM FRIDAY...
SATURDAY: AS THE INLAND LOW OVER THE EASTERN GREAT LAKES MOVES INTO
THE SOUTHEAST CANADA...IT WILL DRAG A DRY COLD FRONT THROUGH THE
AREA SATURDAY AFTERNOON/EVENING. LATE ONSET OF CAA WILL RESULT IN
MILDISH TEMPERATURES ACROSS CENTRAL ON SATURDAY RANGING FROM LOWER
50S NW PIEDMONT TO UPPER 50S ACROSS THE SOUTHEAST.
SATURDAY NIGHT: THE CLOSED UPPER LEVEL LOW THAT TRACKED INLAND OVER
THE PACIFIC NORTHWEST LAST NIGHT WILL CONTINUE TO DEVOLVE INTO AN
OPEN WAVE AS IT DROPS SOUTHEAST ACROSS THE SOUTHERN ROCKIES TONIGHT
AND THEN OVER THE SOUTHERN PLAINS AND INTO CENTRAL GULF COAST REGION
BY SATURDAY NIGHT. MODELS HAVE COME INTO BETTER AGREEMENT WITH A
SUPPRESSED SOUTHERN STREAM SURFACE CYCLOGENESIS OVER THE GULF/DEEP
SOUTH WITH LITTLE TO PRECIP EXPECTED FROM THIS SYSTEM.
INSTEAD...CENTRAL NC COULD SEE SOME VERY LIGHT PRECIP ACROSS THE
AREA LATE SATURDAY NIGHT/SUNDAY MORNING AS NORTHERN STREAM SHORTWAVE
APPROACHES THE AREA FROM THE WEST. GIVEN FAVORABLE NOCTURNAL TIMING
AND MODEST CAA FROM EARLIER COLD FRONTAL PASSAGE SATURDAY
AFTERNOON...COULD SEE A BRIEF PERIOD OF LIGHT RAIN AND POSSIBLY EVEN
LIGHT RAIN OR SNOW ACROSS THE FAR NW PIEDMONT WHERE MODELS SHOW
SURFACE WET-BULBS AROUND FREEZING. AT THIS TIME PRECIP AMOUNTS ARE
TOO LIGHT AND TEMPERATURE PROFILES ARE MARGINALLY COLD ENOUGH TO
SUPPORT MUCH MORE THAN A "GEE WHIZ" SIGHTING OF SNOW. LOWS IN THE
LOWER 30S NW PIEDMONT TO UPPER 30S SOUTHEAST.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 230 AM FRIDAY...
SUNDAY AND SUNDAY NIGHT: THE MEDIUM RANGE MODELS ARE COMING INTO
BETTER AGREEMENT ON HOW THEY HANDLE THE INTERACTION BETWEEN THE
UPPER LEVEL NORTHERN STREAM SHORTWAVE TROUGH MOVING ACROSS THE OH/TN
VALLEY AND INTO THE MID ATLANTIC AND A SOUTHERN STREAM LOW THAT
DEVELOPS OVER THE GULF OF MEXICO. BOTH THE ECMWF AND GFS BRING THE
SOUTHERN STREAM LOW ACROSS THE GULF COAST STATES AND OFF THE SE U.S.
ATLANTIC COAST SUNDAY...KEEPING THE PRECIPITATION...ALL LIQUID...
ALONG AND EAST OF US-1. THE SHORTWAVE HOWEVER MAY GENERATE ITS OWN
PRECIPITATION...WHICH COULD BE NON-LIQUID OR A RAIN/SNOW MIX. THE
PRECIP...REGARDLESS OF TYPE...WILL LIKELY ALL OCCUR BETWEEN 09Z AND
15Z SUNDAY...WITH SOME RAIN LINGERING ACROSS THE FAR EAST INTO THE
EARLY AFTERNOON...AND RESULT IN LITTLE ACCUMULATION. DO NOT EXPECT
ANY SIGNIFICANT IMPACTS AT THIS TIME. HIGHS IN THE MID 40S EXPECTED.
THE COLD SURFACE HIGH WILL START BUILDING INTO THE REGION SUNDAY
NIGHT...WITH CLEARING SKIES BUT WINDS STAYING UP AROUND 5 MPH. AS A
RESULT...LOWS WILL BE COOLER THAN PREVIOUS NIGHTS...LOW 20S NW TO
UPPER 20S SE...FEELING MORE LIKE MID TEENS NW TO MID 20S SE AROUND
DAYBREAK MONDAY.
MONDAY AND TUESDAY: THIS PERIOD IS EXPECTED TO BE COLD AND DRY AS
CANADIAN HIGH PRESSURE BUILDS IN AT THE SURFACE. AS THE UPPER LEVEL
TROUGH PROGRESSES THROUGH THE REGION THE FLOW ALOFT WILL GRADUALLY
BECOME MORE NWRLY. HIGHS MON AND TUE WILL BE FAIRLY STEADY ACROSS
THE NORTH...LOW TO MID 30S...WITH MID 30S TO AROUND 40 DEGREES SOUTH.
LOWS SHOULD BOTTOM OUT MON NIGHT...MID TEENS NW TO LOW 20S SE...
INCREASING A FEW DEGREES TUE NIGHT...LOW TO MID 20S. CURRENT
APPARENT TEMPERATURES TUESDAY MORNING RANGE FROM 10 DEGREES NW TO
MID TEENS SE.
WEDNESDAY AND THURSDAY: TEMPS WILL MODERATE WED AND THU...WITH HIGHS
BACK INTO THE 40S AND LOWS INCREASING FROM THE MID TO UPPER 20S WED
NIGHT TO UPPER 20S TO LOW 30S THU NIGHT. SIGNIFICANT DIFFERENCES IN
THE MEDIUM RANGE MODELS FOR MID TO LATE WEEK YIELD LOW FORECAST
CONFIDENCE...BUT FOR NOW THE FORECAST APPEARS TO BE DRY.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 705 AM FRIDAY...
24 HOUR TAF PERIOD: VFR CONDITIONS THIS WILL GIVE WAY TO WIDESPREAD
IFR TO LIFR CONDITIONS IN RAIN THIS AFTERNOON AND EVENING.
A DEVELOPING AREA OF LOW PRESSURE ALONG THE NORTHERN GULF OF MEXICO
WILL TRACK NEWD THROUGH THE SOUTHEAST TODAY AND THEN ACROSS NORTH
CAROLINA THIS EVENING...BEFORE MOVING UP THE MID-ATLANTIC ON
SATURDAY.
RAIN WILL SPREAD SW TO NE INTO THE AREA LATE THIS MORNING THROUGH
THE EVENING WITH CEILINGS DETERIORATING TO IFR AND POSSIBLY LIFR INTO.
RAIN WILL BE MODERATE TO HEAVY AT TIMES...SO EXPECT SIGNIFICANT
REDUCTION IN VISIBILITIES AS WELL. RAIN SHOULD TAPER OFF FROM SW TO
NE BETWEEN 00Z TO 06Z...WITH VFR CONDITIONS RETURNING SATURDAY
MORNING.
OUTLOOK: AN UPPER LEVEL DISTURBANCE MOVING THROUGH THE AREA LATE
SATURDAY/SUNDAY MORNING COULD BRING SOME MVFR CEILINGS ACROSS THE
AREA ALONG WITH A BRIEF PERIOD OF RAIN/SNOW MIX. VFR CONDITIONS WILL
THEN DOMINATE EARLY TO MID NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...CBL/22
SHORT TERM...CBL
LONG TERM...KC
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1141 PM CST THU JAN 14 2016
.UPDATE...
ISSUED AT 1141 PM CST THU JAN 14 2016
TWEAKED POPS A BIT FOR A FEW SPOTS STILL SEEING LINGERING SNOW IN
THE FAR SOUTHEASTERN COUNTIES...BUT OTHERWISE OUR SNOWFALL IS
WRAPPING UP. A FEW SITES SEEING LOWERED VIS AS WINDS KICK UP
SNOW...BUT NOTHING LESS THAN 2 MILES. CLEARING SKIES CONTINUE TO
SPREAD SOUTH BUT SOME CLOUDS ARE STARTING TO MOVE BACK IN JUST
WEST OF DEVILS LAKE.
UPDATE ISSUED AT 926 PM CST THU JAN 14 2016
VIS HAS COME UP TO 4SM AT PKD AND OVER 2SM AT DTL...AND THERE
SEEMS TO BE A WEAKENING TREND...SO WENT AHEAD AND LET THE HEADLINE
EXPIRE AT 03Z. THE WINDS HAVE BEEN PICKING UP A BIT FROM THE NORTH
BEHIND THE BAND...WITH SOME DRIFTING SNOW AND EVEN VIS REDUCTIONS
TO 1SM AT KFAR. THINK IT WILL BE SHORT LIVED SO JUST INSERTED A
MENTION IN THE EXPIRATION STATEMENT BUT WILL MONITOR IN CASE THE
WINDS LAST A BIT LONGER THAN EXPECTED. SFC HIGH PRESSURE HAS BEEN
BUILDING INTO THE NORTHERN CWA AND THERE HAS BEEN QUITE A BIT OF
CLEARING ACROSS THE NORTH. ADJUSTED CLOUD COVER FOR THIS CLEARING
AREA MOVING SOUTH THROUGHOUT THE NIGHT. THINK THAT CLOUDS WILL
MOVE BACK INTO THE NORTH LATE BUT NOT BEFORE TEMPS BOTTOM OUT NEAR
-10 IN THAT AREA. CURRENT READINGS HAVE A GOOD START.
UPDATE ISSUED AT 709 PM CST THU JAN 14 2016
ADJUSTED THE HEADLINE A BIT...AS SNOW CONTINUES OVER THE
SOUTHEASTERN COUNTIES IN THE ADVISORY. RADAR RETURNS ARE GOING
DOWN BUT PARTLY BECAUSE OF THE BEAM HEIGHT ISSUES. VIS AT DETROIT
LAKES HAS BEEN AROUND 1 TO 1 1/2 MILES FOR THE LAST FEW
HOURS...AND THE RAP HAS THE FRONTOGENESIS HANGING AROUND THROUGH
EARLY EVENING OVER WEST CENTRAL MINNESOTA. WILL EXTEND PART OF THE
ADVISORY UNTIL 03Z...BUT LET CASS...NORMAN...EASTERN POLK AND
NORTHERN CLEARWATER GO AS THE SNOW HAS ALREADY OR NEARLY CLEARED
THOSE AREAS.
UPDATE ISSUED AT 608 PM CST THU JAN 14 2016
PUT OUT A QUICK UPDATE TO TRIM THE WESTERN AND NORTHERN ENDS OF
THE ADVISORY OUT. THE WHOLE THING EXPIRES AT 7...AND WILL MONITOR
OVER THE NEXT HOUR AND DECIDE IF WE NEED TO EXTEND ANY PART OF THE
REMAINING COUNTIES OR IF THE BAND WILL DIMINISH ENOUGH TO LET IT
GO COMPLETELY.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 318 PM CST THU JAN 14 2016
AS THE CURRENT SNOW EVENT WINDS DOWN...THE FOCUS WILL SHIFT BACK
TO THE COLD AND WIND CHILLS AGAIN. AS OF NOW...SEEING THE LIGHT
SNOW ENDING ACROSS THE DEVILS LAKE REGION. THE SNOW SHOULD BE
DECREASING ACROSS THE GRAND FORKS TO JAMESTOWN CORRIDOR IN THE
NEXT HOUR OR SO. THE SNOW WILL TAKE THE LONGEST TO CLEAR FROM
WEST CENTRAL MN. RADAR SHOWS THAT AREAS ALONG THE ND/SD BORDER
INTO WEST CENTRAL MN WILL BEGIN TO RECEIVE A LITTLE SNOW TOO OVER
THE NEXT FEW HOURS. NO SHIFT TO THE MAIN CORRIDOR OF 3 TO 5
INCHES...FROM NEW ROCKFORD TO HILLSBORO TO PARK RAPIDS...WHICH
WILL END FROM WEST TO EAST OVER THE NEXT FEW HOURS. CURRENT
ADVISORY ENDS AT 7 PM...BUT SHOULD BE ABLE TO TRIM SOME COUNTIES
FROM WEST TO EAST PRIOR TO THAT TIME. AFTER ADVISORY ENDS WILL BE
DEALING MORE WITH TEMPS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 318 PM CST THU JAN 14 2016
STILL LOOKING QUITE FRIGID THIS WEEKEND AND WILL BE DEALING WITH
WIND CHILL PRODUCTS FOR MOST OF IT.
A FRIGID ARCTIC AIRMASS WILL BE IN PLACE EARLY IN THE LONG
TERM...WITH TEMPERATURES BEING SUB ZERO THROUGH TUESDAY WHEN
DAYTIME HIGHS WILL BE IN LOW SINGLE DIGITS ABOVE ZERO. THIS SUPER
DRY AIRMASS WILL BE HARD TO OVERCOME...HOWEVER MODELS DO INDICATE
AN UPPER WAVE IN THE NW FLOW ALOFT MOVING ACROSS THE REGION IN THE
TUESDAY TIMEFRAME. THIS COULD PROVIDE A LIGHT DUSTING OF SNOW BUT
NOT SUFFICIENT MOISTURE FOR ANYTHING SIGNIFICANT. THE REMAINDER OF
THE WORK WEEK WILL BE DRY WITH MUCH MILDER (WARMER) TEMPERATURES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1141 PM CST THU JAN 14 2016
VFR CIGS ARE SPREADING SOUTH AND EASTWARD AS THE CLEARING SPOT HAS
BEEN A BIT FASTER TO MOVE SOUTH THAN EXPECTED. SNOW HAS CLEARED
OUT OF ALL TAF SITES BUT KBJI...SOME BLSN OF AROUND 1 OR 2SM HAS
BEEN FOUND AT ISOLATED SPOTS ON AND OFF BUT AS WINDS DECREASE THAT
THREAT SHOULD DIMINISH. SOME CIGS STARTING TO MOVE IN WEST OF KDVL
ARE MOSTLY VFR ALTHOUGH A FEW SPOTS HAVE SHOWN SOME MVFR OR EVEN
IFR CIGS MIXED IN SO WILL HAVE TO KEEP A CLOSE EYE ON THE CLOUDS.
THE DECK OVER CANADA EXPECTED TO MOVE SOUTH LATER IN THE PERIOD
HAS NOT MADE MUCH PROGRESS. THUS...WILL HAVE VFR CONDITIONS
CONTINUE THROUGH TONIGHT...WITH A BIT OF VFR CIGS MOVING IN DURING
THE EARLY MORNING. WILL HOLD OFF ANY MVFR UNTIL LATE MORNING AT
KDVL OR AFTERNOON FURTHER SOUTH AND EAST. WINDS WILL CONTINUE TO
BE FROM THE NORTH TO NORTHWEST THROUGHOUT THE PERIOD WITH
DECREASING SPEEDS AS HIGH PRESSURE BUILDS INTO THE REGION.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...GODON
LONG TERM...GODON/SPEICHER
AVIATION...JR
AREA FORECAST DISCUSSION
NWS NORMAN OK
334 PM CST FRI JAN 15 2016
.DISCUSSION...
ACCUMULATING SNOW LATE TONIGHT INTO SATURDAY IS THE MAIN CONCERN.
EXPANDED THE WINTER WEATHER ADVISORY A BIT FARTHER EAST TO INCLUDE
THE LAWTON...ANADARKO...AND CHICKASHA AREAS BASED ON LATEST MODEL
GUIDANCE...PARTICULARLY THE RUC13 AND HRRR. CONFIDENCE IS RATHER
HIGH THAT 1 TO 3 INCHES OF WET SNOW WILL OCCUR IN THESE AREAS.
TONIGHT...CLOUDS WILL QUICKLY INCREASE. PRECIPITATION WILL BEGIN
IN FAR WESTERN OKLAHOMA AS EARLY AS 10 PM...BUT MAINLY HOLD OFF
UNTIL AFTER 2 AM. MOST PRECIPITATION SHOULD BEGIN AS LIGHT RAIN
DUE TO WARM BOUNDARY LAYER TEMPERATURES NEAR THE GROUND. AS THE
AIR NEAR THE GROUND COOLS AND SATURATES...PRECIPITATION SHOULD
MAINLY CHANGE FROM LIGHT RAIN TO LIGHT TO MODERATE SNOW. A BRIEF
PERIOD OF SLEET MAY OCCUR DURING THIS TRANSITION...BUT WAS NOT
MENTIONED IN THE GRIDS AS RAIN OR SNOW SHOULD BE THE PRIMARY
PRECIPITATION TYPES.
LATEST MODEL GUIDANCE...PARTICULARLY THE HRRR...HAS BEEN DEPICTING
BANDS OF PRECIPITATION OCCURRING LATE TONIGHT INTO SATURDAY
MORNING...LIKELY AS A RESULT OF 850-700 MB FRONTOGENESIS. THESE
BANDS SEEM TO BE MOST LIKELY IN THE 3 AM TO 11 AM TIME FRAME NEAR
AND JUST SOUTH OF I-40 WEST OF OKLAHOMA CITY. THESE BANDS WILL
HAVE THE GREATEST POTENTIAL TO PRODUCE ACCUMULATING SNOWFALL AS
THE SNOW MAY BE MODERATE TO PERHAPS HEAVY AT TIMES WITH
VISIBILITIES FALLING TO 1/2 MILE OR LESS. MODERATE TO HEAVY SNOW
WOULD BE NECESSARY TO ACCUMULATE ON ROADWAYS DUE TO WARM GROUND
TEMPERATURES FROM HEATING THIS AFTERNOON AND YESTERDAY.
BY SATURDAY MORNING...MOST SNOW BANDS APPEAR TO BE OVER
SOUTHWESTERN OKLAHOMA...SLOWLY WEAKENING AFTER 11 AM. RIGHT
NOW...APPEARS THE HEAVIEST SNOW WILL OCCUR SOUTH OF THE OKLAHOMA
CITY METRO AREA AND NORTH OF WICHITA FALLS. LOCATIONS IN SOUTHERN
OKLAHOMA INCLUDING PAULS VALLEY...DUNCAN...AND ADA...MAY BE IN THE
HEAVIEST BANDS OF SNOW AS WELL...THOUGH NOT CONFIDENT THAT THIS
WILL BE THE CASE.
OVERALL...THINK 1 TO 3 INCHES OF SNOWFALL ACCUMULATION IN
ADVISORY AREA SEEM REASONABLE...THOUGH WOULD NOT BE SURPRISED IF
LOCALLY HEAVIER AMOUNTS WOULD BE POSSIBLE IF A MODERATE TO HEAVY
BAND OF SNOW SET UP OVER A GIVEN AREA FOR SEVERAL HOURS. MOST
ACCUMULATIONS WILL BE ON GRASSY SURFACES DUE TO WARM GROUND
SURFACES. SURFACE TEMPERATURES SHOULD STAY NEAR OR JUST ABOVE
FREEZING...32 DEGREES...IN MOST LOCATIONS THAT RECEIVE
ACCUMULATING SNOWFALL.
SATURDAY AFTERNOON THROUGH SUNDAY MORNING...PRECIPITATION CHANCES
WILL END AND SKIES SHOULD CLEAR. WOULD NOT BE SURPRISED IF LIGHT
FOG OR FREEZING FOG FORMED ACROSS SNOW COVERED AREAS...BUT DID
NOT MENTION DUE TO LOW CONFIDENCE OF OCCURRENCE.
SUNDAY AFTERNOON AND NIGHT...A STRONG COLD FRONT WILL MOVE
THROUGH THE AREA AND BRING COLDER TEMPERATURES. MOISTURE APPEARS
TO BE LIMITED WITH THE FRONTAL PASSAGE...THOUGH A FEW LIGHT
SPRINKLES OR SNOW FLURRIES COULD RESULT. THERE IS AN OUTSIDE
CHANCE FOR ADDITIONAL BAND OF SNOWFALL SUNDAY NIGHT SOMEWHERE
ACROSS THE AREA...PARTICULARLY NEAR THE RED RIVER. TEMPERATURES
WILL PLUMMET SUNDAY NIGHT INTO THE TEENS AND 20S.
MONDAY THROUGH FRIDAY...A WARMING TREND WILL OCCUR THROUGH
MIDWEEK. ANOTHER STORM SYSTEM MAY BRING ADDITIONAL PRECIPITATION
CHANCES WEDNESDAY THROUGH FRIDAY...THOUGH PRECIPITATION TYPES AND
AMOUNTS REMAIN UNCERTAIN.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 31 43 27 39 / 60 70 0 10
HOBART OK 32 39 28 42 / 60 100 0 10
WICHITA FALLS TX 35 42 29 50 / 20 80 0 10
GAGE OK 25 44 25 31 / 60 20 0 10
PONCA CITY OK 26 43 25 32 / 10 10 0 10
DURANT OK 35 43 29 49 / 10 60 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST
SATURDAY FOR OKZ009-014-016-021>023-027-033>036-038.
TX...NONE.
&&
$$
23/17
AREA FORECAST DISCUSSION
NWS PORTLAND OR
852 AM PST FRI JAN 15 2016
.SYNOPSIS...BRIEF BREAK IN THE WEATHER TODAY...BUT NEXT FRONT ARRIVES
TONIGHT. WILL BE A WET AND BREEZY WEEKEND...WITH SNOW ABOVE THE
PASSES IN THE CASCADES. AFTER A DRY DAY ON MON...UNSETTLED WEATHER
PATTERN CONTINUES NEXT WEEK.
&&
.UPDATE...A FEW SHOWERS LINGER OVER THE INTERIOR LOWLANDS THIS
MORNING AND IS EXPECTED TO CONTINUE TO DIMINISH. THERE ARE MORE
SHOWERS OVER THE SOUTH WA CASCADES AND THE NORTHERN COAST/COAST RANGE
ZONES.LATEST HRRR AND NAM SHOW SCATTERED SHOWERS PERSISTING IN
THESE AREAS SO WILL INCREASE POPS IN THOSE AREAS. HRRR AND GFS TIMING
OF NEXT BOUT OF RAIN IN GOOD AGREEMENT WITH LIGHT RAIN REACHING THE
COAST LATE THIS AFTERNOON AND EVENING FOR THE INTERIOR. NAM HAS
SLOWER TIMING BUT IT MAY BE A BIAS IN THE MODEL HANDLING WARM
ADVECTION PCPN. SAT SYSTEM LOOKS A LITTLE WINDIER FOR THE COAST THAN
CURRENT FORECAST AND WILL ADDRESS THAT IN THE AFTERNOON UPDATE ONCE
WE HAVE FULL MODEL SUITE. /MH
PREVIOUS DISCUSSION FOLLOWS...
.SHORT TERM...TODAY THROUGH MONDAY...
A WEAK UPPER DISTURBANCE OFFSHORE COMBINED WITH ONSHORE FLOW WILL
MAINTAIN A MINOR THREAT OF SHOWERS TODAY...MAINLY THIS AM. APPEARS
WILL SEE GENERALLY DRY CONDITIONS FOR AFTERNOON INTO THIS EVENING.
LIKELY TO BE LAST DECENT RAIN-FREE PERIOD UNTIL EARLY NEXT WEEK.
UPPER RIDGING OFFSHORE WILL PUSH OVER THE PAC NW TODAY...BUT IS BEING
PUSHED INLAND AS STRONG SYSTEM UPSTREAM APPROACHES. MODELS STILL
RATHER GOOD AGREEMENT WITH PRECIPITATION SHIELD REACHING THE COAST BY
LATE THIS AFTERNOON...AND SPREADING INLAND THIS EVENING. THIS SYSTEM
HAS TAPPED SUBTROPICAL MOISTURE...WITH A RESPECTABLE PRECIPITABLE
WATER PLUME. BOTH GFS AND NAM MODELS SHOW PRECIPITABLE WATER VALUES
OF 1.20 TO 1.25 PUSHING OVER THE REGION LATE TONIGHT AND EARLY SAT
AM. THIS WILL SUPPORT RAINFALL TONIGHT/SAT AM OF 1 TO 3 INCHES OVER
THE MTNS...WITH HEAVIEST OVER THE COAST MTNS...AND GENERALLY 0.50 TO
1.00 INCH ELSEWHERE.
WILL BECOME BREEZY ALONG THE COAST AS WILL SEE BIT OF LOW LEVEL
BARRIER JET FORM NEAR THE COAST LATER TONIGHT INTO SAT AM AHEAD OF
THE COLD FRONT. SHOULD BE ENOUGH TO SUPPORT GUSTS OF 45 TO 55 MPH ON
THE COAST. WINDS EASE AS FRONT PUSHES ONSHORE EARLY SAT AFTERNOON.
MODELS HAVE BEEN BIT SUGGESTIVE OF A SURFACE LOW FORMING OFFSHORE
LATER SAT AFTERNOON...AND SWINGING THE LOW INTO W WASHINGTON BY SAT
EVENING. THIS LOW WILL TIGHTEN PRES GRADIENTS OVER REGION... WITH
BREEZY SOUTH WINDS FOR SAT AFTERNOON/EARLY EVENING. LIKELY TO SEE
GUSTS 40 TO 50 MPH ALONG THE COAST AND OVER COAST RANGE...WITH GUSTS
20 TO 30 MPH FURTHER INLAND IN THE AFTERNOON.
SNOW LEVELS ARE AROUND 2500 TO 3000 FEET THIS AM...BUT WILL SLOWLY
RISE TODAY AND THIS EVENING. AS THE WARMER AIR WITH THE FRONT
TONIGHT...SNOW LEVELS WILL RISE MORE QUICKLY TONIGHT...AND SIT
BETWEEN 5500 AND 6500 FT SAT AM. ONCE COLD FRONT MOVES INLAND... SNOW
LEVELS LOWER AGAIN...DOWN TO NEAR 4000 FEET BY SAT EVENING.
SHOWERS WILL DECREASE SAT EVENING...BUT ANOTHER FAST MOVING SYSTEM
WILL ARRIVE LATER SAT NIGHT AND SUN. THIS WILL BE A VERY WET DAY FOR
SUN...WITH RAINFALL BIT MORE THAN THAT OF SAT AM. STRONG SW 125 KT
JET ALOFT WILL HELP PUSH THE COLD FRONT ONSHORE SUN AFTERNOON. WILL
HAVE TO WATCH WEATHER PATTERN AS SOME POTENTIAL FOR AN BOOST OF WINDS
ALONG THE COAST AS LOW LEVEL BARRIER JET TRIES TO FORM. MODELS
SHOWING 1500 FT WINDS OVER COASTAL WATERS OF 55 TO 70 MPH...WHICH
COULD CONTRIBUTE TO GUSTY SOUTH WINDS ON HEADLANDS OF 50 TO 60 MPH.
AGAIN...WILL HAVE LATER SHIFTS LOOK AT THIS POTENTIAL.
LIKE SAT...SNOW LEVELS LIFT UP TO 6000 FT BRIEFLY ON SUN...THEN BACK
TO 4000 OR 4500 FT SUN NIGHT. MODELS HAVE CONTINUED TREND OF SHOWING
REGION BETWEEN SYSTEMS ON MON. SO...HAVE CUT BACK ON POPS AND CLOUDS
FOR MON. OVERALL...MON LOOKS TO BE A DRY DAY...WITH A SHOWER OR TWO
OVER THE CASCADES EARLY. UNFORTUNATELY...CLOUDS INCREASING LATE IN
DAY AS PARADE OF FRONTS CONTINUES. /ROCKEY
.LONG TERM...MONDAY NIGHT THROUGH THURSDAY...
THE STRONG NORTH PACIFIC ZONAL JET CONTINUES THROUGH THE EXTENDED
WITH IT SPLITTING AS IT NEARS THE WEST COAST. LIKE RECENT SYSTEMS
SOME OF THE ENERGY SPINS OVER THE FORECAST AREA WHILE THE MAJORITY OF
THE ENERGY AND MOISTURE HEADS TOWARD CALIFORNIA. ALSO CLIMATE
PREDICTION CENTER 6-10 DAY SHOWS THE MEAN 500 MB RIDGE POSITION OVER
EASTERN OREGON AND IDAHO LEAVING THE FORECAST AREA OPEN TO PACIFIC
SYSTEMS. MODELS CONTINUE TO SHOW UPPER LEVEL RIDGING BUILDING OVER
THE AREA ON WEDNESDAY AND GIVE US A BRIEF PERIOD OF RELIEF FROM THE
RAIN...BUT CONFIDENCE IS LOW SO WILL MAINTAIN AT LEAST CLIMO POPS IN
THE FORECAST. SEASONAL TEMPERATURES EXPECTED THROUGH NEXT WEEK. /MH
&&
.AVIATION...MOSTLY MVFR CONDITIONS WILL RISE TO MOSTLY VFR THIS
AFTERNOON AS RESIDUAL SHOWERS LIFT NORTH OF THE AREA. THE NEXT
STRONG OCCLUDED FRONT WILL BRING MORE RAIN TO THE AREA TONIGHT AND
SATURDAY MORNING...AND LOWERING CONDITIONS TO MVFR.
LIGHT EAST WINDS THROUGH THE COLUMBIA RIVER GORGE TODAY WILL
RESTRENGTHEN AGAIN LATER TONIGHT.
KPDX AND APPROACHES...CONDITIONS LIFTING TO MAINLY VFR THIS
MORNING AND AFTERNOON. MORE RAIN AND LOWERING CIGS EXPECTED AFTER
MIDNIGHT TONIGHT...POSSIBLY LOWERING CONDITIONS TO MVFR LATER
TONIGHT AND SATURDAY MORNING. PT
&&
.MARINE...THE SYSTEM FROM THURSDAY WAS LIFTING NORTH OF OUR AREA
THIS MORNING. WINDS HAVE BACKED TO THE SOUTH AHEAD OF THE NEXT
SYSTEM...AND ARE ABOVE SMALL CRAFT ADVISORY CRITERIA. WINDS WILL
CONTINUE TO RAMP UP AS THE NEXT SYSTEM APPROACHES...REACHING HIGH
END GALES TONIGHT AND SATURDAY MORNING BEFORE THE OCCLUDED FRONT
WITH THAT SYSTEM MOVES ONSHORE. WE MAY GET VERY CLOSE TO STORM
FORCE IN THE OUTER WATERS. WINDS EAST BACK TO SMALL CRAFT
ADVISORY THRESHOLDS SATURDAY AFTERNOON BEHIND THE FRONT. FOR
NOW...THE NAM MODEL LOOKS OVERDONE WITH A SECONDARY LOW OFF THE
COAST LATER SATURDAY AND SATURDAY EVENING. THE NEXT STRONG FRONT
BRINGS MORE HIGHER END GALES TO THE WATERS LATER SATURDAY NIGHT
AND SUNDAY MORNING.
EVEN A BIT HIGHER THAN THE WAVE MODELS SUGGESTED...SEAS HAVE
REACHED 15 OR 16 FT THIS MORNING AT OUR BUOYS AND WILL STAY NEAR
THAT FOR A WHILE TODAY BEFORE EASING BACK DOWN A COUPLE OF FEET
LATER TODAY AND THIS EVENING. SEAS WILL LIKELY GET CLOSE TO 20 FT
LATER TONIGHT AND SATURDAY MORNING...ESPECIALLY IF WE KNOCK ON THE
STORM FORCE DOOR FOR THE WINDS. SEAS DROP DOWN TO 15 TO 17 FT
LATER SATURDAY AND SATURDAY NIGHT BEFORE BUILDING BACK CLOSE TO 20
FT WITH THE NEXT FRONT LATER SATURDAY NIGHT AND EARLY SUNDAY.
ANOTHER AREA HIGHER SEAS SPREADS IN LATER SUNDAY AND SUNDAY
EVENING...WITH SEAS REACHING THE 22 TO 25 FT RANGE. PT
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 PM PST THIS
AFTERNOON FOR COASTAL WATERS FROM CAPE SHOALWATER WA
TO FLORENCE OR OUT 60 NM.
GALE WARNING FROM 4 PM THIS AFTERNOON TO 1 PM PST SATURDAY
FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR
OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST
THIS AFTERNOON FOR COASTAL WATERS FROM CAPE SHOALWATER WA
TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
6 AM PST SATURDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1150 PM CST THU JAN 14 2016
.UPDATE...A DENSE FOG ADVISORY HAS BEEN ISSUED FOR AREAS EAST OF
I-35 AND I-37. SURFACE OBSERVATIONS AND WEBCAMS ACROSS THIS REGION
OF THE CWA CONFIRM DENSE FOG HAS DEVELOPED OR IS IN THE PROCESS
OF DEVELOPING.
&&
.PREV DISCUSSION... /ISSUED 1059 PM CST THU JAN 14 2016/
AVIATION...
FOG HAS BEGUN TO FORM AND VIS AT SSF HAS BEEN BOUNCING BETWEEN
MVFR AND IFR. EXPECT THIS TREND TO CONTINUE FOR THE NEXT SEVERAL
HOURS IN SAN ANTONIO AND AUSTIN. DRT SHOULD REMAIN VFR THROUGH
THE NIGHT. WIND SHIFT TO THE WEST AND THEN NORTHWEST SHOULD BRING
DRIER AIR AND VFR CONDITIONS. NORTH TO NORTHWEST WINDS WILL
CONTINUE THROUGH THE DAY FRIDAY AT ALL TERMINALS.
PREV DISCUSSION... /ISSUED 1032 PM CST THU JAN 14 2016/
UPDATE...BASED ON CURRENT AND EXPECTED TRENDS, PATCHY AND AREAS
OF FOG HAVE BEEN INTRODUCED ALONG THE I-35/37 CORRIDOR AND EAST
INTO THE SOUTHEAST COASTAL PLAINS. SOME LOCATIONS ACROSS FAR
SOUTHEAST COUNTIES LIKE LAVACA...FAYETTE...AND PORTIONS OF
GONZALES AND DEWITT COULD EXPERIENCE SOME AREAS OF DENSE FOG.
THIS WORDING HAS BEEN INTRODUCED INTO THE LATE EVENING AS WELL AS
THE OVERNIGHT GRIDS WILL SUPPORT FROM THE HRRR AND NAM BUFR
SOUNDINGS. A DRYLINE/PACIFIC FRONT WILL MOVE THROUGH EARLY FRIDAY
AND HELP CLEAR THE FOG BY 8 TO 9AM. NO OTHER WEATHER UPDATES WERE
MADE AND THE UPDATED ZONES ARE OUT.
PREV DISCUSSION... /ISSUED 236 PM CST THU JAN 14 2016/
SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
THE UPPER LEVEL LOW IS CURRENTLY CENTERED NEAR EDWARDS COUNTY AND
CONTINUES TO MOVE EAST. THE MAIN SHOWER AND THUNDERSTORM ACTIVITY
IS WELL OFF THE COAST AND CHANCES FOR RAIN FOR OUR CWA ARE FAIRLY
LOW FOR THE REST OF THE AFTERNOON. WILL CARRY NO POPS FOR THE
TONIGHT PERIOD AS ALL ACTIVITY SHOULD BE FARTHER EAST OF THE
REGION. A WEAK FRONTAL BOUNDARY IS EXPECTED TO PUSH THROUGH THE
REGION OVERNIGHT BEHIND THE DEPARTING LOW PRESSURE SYSTEM. LOWS
TONIGHT SHOULD BE IN THE 40S ACROSS MUCH OF THE AREA WITH THE
SLIGHTLY COOLER READINGS ACROSS THE NORTHWEST CWA WHERE THE FRONT
MOVES IN A BIT EARLIER. WINDS ARE EXPECTED TO RETURN TO THE SOUTH
BY TOMORROW AFTERNOON AND HIGH TEMPERATURES ARE EXPECTED TO REACH
THE UPPER 60S TO LOWER 70S. WITH DEWPOINTS REMAINING IN THE MID-
20S TOMORROW AFTERNOON...HUMIDITY VALUES WILL BOTTOM OUT IN THE
TEENS ACROSS THE WESTERN COUNTIES BUT WINDS SHOULD REMAIN BELOW 15
MPH. LOWS FRIDAY NIGHT SHOULD BE IN THE 40S ONCE AGAIN MOSTLY
CLEAR TO PARTLY CLOUDY SKIES.
LONG TERM (SATURDAY THROUGH THURSDAY)...
THE NEXT SHORTWAVE IS EXPECTED TO PUSH THROUGH THE AREA SATURDAY
MORNING. THIS SMALL BUT STRONG SYSTEM WILL BRING A SMALL CHANCE OF
RAIN TO MAINLY THE EASTERN COUNTIES SATURDAY AFTERNOON. BEHIND THE
SYSTEM WINDS WILL BE QUITE STRONG DURING THE AFTERNOON HOURS
ACROSS THE WESTERN COUNTIES. MODELS ARE SHOWING 850 WINDS OUT OF
THE NORTHWEST AROUND 40 KNOTS. SHOULD SEE ENOUGH MIXING TO HAVE
SUSTAINED 20-25 MPH WINDS AT THE SURFACE AT LEAST. SHOULD BE CLOSE
TO WIND ADVISORY CRITERIA FOR THIS AREA...BUT WILL PROBABLY JUST
BELOW THE 26 MPH SUSTAINED CRITERIA. HUMIDITY VALUES WILL BE
HIGHER THAN FRIDAY AND NOT EXPECTING MUCH OF A FIRE WEATHER ISSUE
ESPECIALLY WITH CONTINUED MOIST FUELS. ANOTHER WEAK FRONT IS
EXPECTED TUESDAY NIGHT...BUT WILL NOT HAVE MUCH OF AN EFFECT ON
RAIN CHANCES OR TEMPERATURES. A STRONGER SYSTEM IS EXPECTED AROUND
NEXT THURSDAY WHICH COULD BRING OUR NEXT CHANCES OF RAIN...MAINLY
IN THE EASTERN COUNTIES ONCE AGAIN.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 47 68 42 60 35 / 0 0 0 20 0
AUSTIN BERGSTROM INTL AIRPORT 44 67 38 60 34 / 0 0 0 20 0
NEW BRAUNFELS MUNI AIRPORT 45 69 40 63 33 / 0 0 0 20 0
BURNET MUNI AIRPORT 43 65 40 55 33 / 0 0 0 20 0
DEL RIO INTL AIRPORT 42 71 44 65 36 / 0 0 0 - 0
GEORGETOWN MUNI AIRPORT 45 66 39 56 32 / 0 0 0 20 0
HONDO MUNI AIRPORT 44 71 42 65 34 / 0 0 0 10 0
SAN MARCOS MUNI AIRPORT 45 68 40 61 34 / 0 0 0 20 0
LA GRANGE - FAYETTE REGIONAL 50 68 42 62 34 / 10 0 - 20 -
SAN ANTONIO INTL AIRPORT 47 70 43 63 37 / 0 0 0 10 0
STINSON MUNI AIRPORT 46 71 43 64 37 / 0 0 0 10 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 8 AM CST FRIDAY FOR THE FOLLOWING
COUNTIES: BASTROP...CALDWELL...DE WITT...FAYETTE...GONZALES...
GUADALUPE...KARNES...LAVACA...LEE...WILSON.
&&
$$
MESOSCALE/AVIATION...04
SYNOPTIC/GRIDS...RUNYEN
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1130 PM CST THU JAN 14 2016
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...WEST SOUTHWEST FLOW ABOVE THE DECK SHOULD BECOME MORE
NORTHWEST AS A TROUGH MOVES EAST OF THE AREA. THE SOUNDING SHOWS
WIDENING TEMP/DEW POINT SPREAD ABOVE THE DECK AND THE POTENTIAL FOR
BOUNDARY LAYER COOLING WITH A LOW LEVEL SURFACE BASED INVERSION
SUPPORTING FOG. HRRR DEW POINT DEPRESSION WILL BE LESS THAN A DEGREE
ALONG THE COAST THROUGH DAWN. LIGHT WINDS...MOSTLY CLEAR SKIES...
ELEVATED DEW POINTS (RELATIVE TO TEMPS) AND SOME GROUND MOISTURE
COULD CONTRIBUTE TO OVERNIGHT FOG. HRRR SURFACE WINDS VEERING FROM
SOUTH TO SOUTHWEST OVERNIGH PROBABLY WON`T SUPPORT FOG HOWEVER.
THE MODEL GUIDANCE HAS DEFINITELY BEEN SOMEWHAT INCONSISTENT WITH
THE EXTENT AND AMOUNT OF FOG...WITH THE 00Z MAV GUIDANCE AGAIN
ADVERTISING SOME DENSE FOG IN THE PREDAWN HOURS FOR THE TAF SITES.
NOT READY TO JUMP ON WIDESPREAD DENSE JUST YET...BUT AVIATION
CONDITIONS COULD STILL DROP TO LIFR CIGS/VSBY IN LOW CLOUDS/FOG
THROUGH MORNING. ADDITIONAL ANALYSIS ONGOING.
&&
.PREV DISCUSSION... /ISSUED 547 PM CST THU JAN 14 2016/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...VFR TAFS UNTIL ABOUT MIDNIGHT...THEN A POSSIBLE DROP
TO LIFR CIGS/VSBY IN LOW CLOUDS/FOG THROUGH MORNING. THE MODEL
GUIDANCE HAS DEFINITELY BEEN SOMEWHAT INCONSISTENT WITH THE
EXTENT AND AMOUNT OF FOG...WITH THE 18Z MAV GUIDANCE AGAIN
ADVERTISING SOME DENSE IN THE PREDAWN HOURS FOR THE TAF SITES.
LIGHT WINDS...MOSTLY CLEAR SKIES...ELEVATED DEW POINTS (RELATIVE
TO TEMPS) AND SOME GROUND MOISTURE COULD CONTRIBUTE TO OVERNIGHT
FOG...AND WILL INCLUDE IN THE TAFS FOR NOW...WITH ADDITIONAL
ANALYSIS ONGOING.
PREV DISCUSSION... /ISSUED 154 PM CST THU JAN 14 2016/
SHORT TERM /NOW THROUGH FRIDAY NIGHT/...LATEST WATER VAPOR IMAGERY
SHOWS 500MB TROUGH CURRENTLY OVER WEST CENTRAL TEXAS WILL BE MOVING
EAST AND EXIST THE STATE DURING THE SHORT TERM PERIOD. COASTAL
TROUGH GENERATED BY THIS TROUGH WILL LIFT NORTHEAST ALONG THE GULF
COAST AND CONTINUE TO ENHANCE A FEW ISOLATED SHOWERS IN THE
OFFSHORE WATERS. THE MID AND LOW LEVEL CLOUD COVER REMAINED OVC TO
BKN ACROSS MUCH THE CWA LIMITING MUCH HEATING TO REACH THE GROUND
AND FOR ANY CONVECTION TO INITIATE. THE CLOUD COVER IN ADDITION TO
THE LOCATION OF THE TROUGH IS NOT FAVORABLY FOR ACTIVITY TO DEVELOP
ACROSS THE AREA. A FEW ISOLATED SHOWERS CAN NOT BE RULED OUT BUT
MAINLY ALONG THE COAST AND OFFSHORE WATERS. TEMPERATURES WILL REACH
THE MID 70S AREAS ALONG THE COAST AND IN THE LOW 70S FURTHER INLAND.
AS THE TROUGH MOVES EAST...DRY AIR MAKES ITS WAY INTO THE AREA
TONIGHT BECOMING CLEAR OVERNIGHT. TEMPERATURES WILL BE A COOLING
INTO THE UPPER 40S OVER THE NORTHERN RANCHLANDS AND WESTERN COUNTIES
WHILE TOWARDS THE EAST COAST REMAIN IN THE MID 50S WITH A LIGHT
SOUTH TO SOUTHWEST FLOW.
FRIDAY...NORTHWEST FLOW ALOFT RETURNS AS RIDGE BEGINS TO BUILD
ACROSS THE REGION. A WEST TO NORTHWEST FLOW NEAR THE SURFACE WITH
ABUNDANT DRY SLOT IN THE AREA WILL FAVOR WARMER TEMPERATURES FRIDAY.
HIGH TEMPS WILL BE IN THE 80S ALONG THE COAST AND UPPER 70S ACROSS
THE WEST WITH CLEAR SKIES. HUMIDITY WILL LOWER INTO THE TEEN WITH
WINDS BUT WINDS WILL REMAIN LIGHT TO MODERATE WHICH WILL LIMIT THE
POTENTIAL FOR FIRE WEATHER CONCERN DURING THE DAY.
LONG TERM /SATURDAY THROUGH THURSDAY/...THE MOST SIGNIFICANT
WEATHER EVENT IN THE LONG TERM PORTION OF THE FORECAST WILL BE THE
SATURDAY MORNING AND AFTERNOON PASSAGE OF A STRONG COLD FRONT IN
ASSOCIATION WITH THE EASTWARD PROGRESSION OF A CLOSED 500 MB LOW
PRESSURE SYSTEM THROUGH THE LONE STAR STATE. ISOLATED/SCATTERED
PRECIPITATION WILL ACCOMPANY THE FRONTAL PASSAGE IN DEEP SOUTH
TEXAS AND THE RIO GRANDE VALLEY...WITH MEX GUIDANCE SUGGESTING
WIND SPEEDS IN THE WAKE OF THE FRONT MAY REACH WIND ADVISORY
CRITERIA FOR ALL OR PORTIONS OF THE BRO CWFA. AFTERWARDS AND FOR
THE REMAINDER OF THE LONG TERM FORECAST PERIOD...A NEARLY ZONAL
500 MB FLOW WILL ALLOW A SERIES OF ONLY WEAK COLD FRONTS TO PASS
THROUGH THE BRO CWFA OR NEAR THE AREA FROM THE NORTH...WITH
ISOLATED RAINFALL NOT RE-ENTERING THE FORECAST UNTIL WEDNESDAY.
TEMPERATURE-WISE...DESPITE THE COLD FRONTAL APPROACHES AND/OR
PASSAGES...NEAR TO ABOVE NORMAL DAYTIME HIGH AND OVERNIGHT LOW
TEMPERATURES ARE ANTICIPATED.
MARINE...NOW THROUGH FRIDAY NIGHT...UPPER TROUGH MOVING EAST ACROSS
THE STATE OF TEXAS WILL LIFT A COASTAL TROUGH NORTHEAST ALONG THE
WESTERN GULF COAST. THIS WILL ENHANCE A FEW ISOLATED SHOWERS OVER
THE OFFSHORE WATERS BUT WILL LIFT AND EXIT NORTHEAST FURTHER OUT
INTO THE GULF. DRY AIR RIGHT BEHIND THIS SYSTEM WILL RETURN WITH A
WEST TO NORTHWEST FLOW AS RIDGE BUILDS ACROSS THE REGION. LIGHT AND
MODERATE WINDS WILL PREVAIL THROUGH THE PERIOD ALLOWING SEAS TO
REMAIN BELOW 2 TO 3 FEET.
SATURDAY THROUGH THURSDAY...LIKELY SMALL CRAFT ADVISORY AND
POSSIBLE GALE WARNING CONDITIONS ARE ANTICIPATED ALONG THE LOWER
TEXAS COAST SATURDAY AFTERNOON AND SATURDAY NIGHT DUE TO THE
PASSAGE OF A COLD FRONT. FOR THE REMAINDER OF THE FORECAST
PERIOD...LIGHT TO MODERATE WINDS AND LOW TO MODERATE SEAS WILL
PREVAIL AS A SERIES OF WEAK COLD FRONTS PASS THROUGH THE LOWER
TEXAS COAST WATERS OR APPROACH THE AREA FROM THE NORTH.
BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 73 57 78 55 / 50 0 0 0
BROWNSVILLE 72 55 80 54 / 40 0 0 0
HARLINGEN 73 54 82 52 / 50 0 0 0
MCALLEN 74 52 82 52 / 30 0 0 0
RIO GRANDE CITY 75 50 80 50 / 20 0 0 0
SOUTH PADRE ISLAND 69 59 73 59 / 50 0 0 0
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
54...AVIATION
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1059 PM CST THU JAN 14 2016
.AVIATION...
FOG HAS BEGUN TO FORM AND VIS AT SSF HAS BEEN BOUNCING BETWEEN
MVFR AND IFR. EXPECT THIS TREND TO CONTINUE FOR THE NEXT SEVERAL
HOURS IN SAN ANTONIO AND AUSTIN. DRT SHOULD REMAIN VFR THROUGH
THE NIGHT. WIND SHIFT TO THE WEST AND THEN NORTHWEST SHOULD BRING
DRIER AIR AND VFR CONDITIONS. NORTH TO NORTHWEST WINDS WILL
CONTINUE THROUGH THE DAY FRIDAY AT ALL TERMINALS.
&&
.PREV DISCUSSION... /ISSUED 1032 PM CST THU JAN 14 2016/
UPDATE...BASED ON CURRENT AND EXPECTED TRENDS, PATCHY AND AREAS
OF FOG HAVE BEEN INTRODUCED ALONG THE I-35/37 CORRIDOR AND EAST
INTO THE SOUTHEAST COASTAL PLAINS. SOME LOCATIONS ACROSS FAR
SOUTHEAST COUNTIES LIKE LAVACA...FAYETTE...AND PORTIONS OF
GONZALES AND DEWITT COULD EXPERIENCE SOME AREAS OF DENSE FOG.
THIS WORDING HAS BEEN INTRODUCED INTO THE LATE EVENING AS WELL AS
THE OVERNIGHT GRIDS WILL SUPPORT FROM THE HRRR AND NAM BUFR
SOUNDINGS. A DRYLINE/PACIFIC FRONT WILL MOVE THROUGH EARLY FRIDAY
AND HELP CLEAR THE FOG BY 8 TO 9AM. NO OTHER WEATHER UPDATES WERE
MADE AND THE UPDATED ZONES ARE OUT.
PREV DISCUSSION... /ISSUED 236 PM CST THU JAN 14 2016/
SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
THE UPPER LEVEL LOW IS CURRENTLY CENTERED NEAR EDWARDS COUNTY AND
CONTINUES TO MOVE EAST. THE MAIN SHOWER AND THUNDERSTORM ACTIVITY
IS WELL OFF THE COAST AND CHANCES FOR RAIN FOR OUR CWA ARE FAIRLY
LOW FOR THE REST OF THE AFTERNOON. WILL CARRY NO POPS FOR THE
TONIGHT PERIOD AS ALL ACTIVITY SHOULD BE FARTHER EAST OF THE
REGION. A WEAK FRONTAL BOUNDARY IS EXPECTED TO PUSH THROUGH THE
REGION OVERNIGHT BEHIND THE DEPARTING LOW PRESSURE SYSTEM. LOWS
TONIGHT SHOULD BE IN THE 40S ACROSS MUCH OF THE AREA WITH THE
SLIGHTLY COOLER READINGS ACROSS THE NORTHWEST CWA WHERE THE FRONT
MOVES IN A BIT EARLIER. WINDS ARE EXPECTED TO RETURN TO THE SOUTH
BY TOMORROW AFTERNOON AND HIGH TEMPERATURES ARE EXPECTED TO REACH
THE UPPER 60S TO LOWER 70S. WITH DEWPOINTS REMAINING IN THE MID-
20S TOMORROW AFTERNOON...HUMIDITY VALUES WILL BOTTOM OUT IN THE
TEENS ACROSS THE WESTERN COUNTIES BUT WINDS SHOULD REMAIN BELOW 15
MPH. LOWS FRIDAY NIGHT SHOULD BE IN THE 40S ONCE AGAIN MOSTLY
CLEAR TO PARTLY CLOUDY SKIES.
LONG TERM (SATURDAY THROUGH THURSDAY)...
THE NEXT SHORTWAVE IS EXPECTED TO PUSH THROUGH THE AREA SATURDAY
MORNING. THIS SMALL BUT STRONG SYSTEM WILL BRING A SMALL CHANCE OF
RAIN TO MAINLY THE EASTERN COUNTIES SATURDAY AFTERNOON. BEHIND THE
SYSTEM WINDS WILL BE QUITE STRONG DURING THE AFTERNOON HOURS
ACROSS THE WESTERN COUNTIES. MODELS ARE SHOWING 850 WINDS OUT OF
THE NORTHWEST AROUND 40 KNOTS. SHOULD SEE ENOUGH MIXING TO HAVE
SUSTAINED 20-25 MPH WINDS AT THE SURFACE AT LEAST. SHOULD BE CLOSE
TO WIND ADVISORY CRITERIA FOR THIS AREA...BUT WILL PROBABLY JUST
BELOW THE 26 MPH SUSTAINED CRITERIA. HUMIDITY VALUES WILL BE
HIGHER THAN FRIDAY AND NOT EXPECTING MUCH OF A FIRE WEATHER ISSUE
ESPECIALLY WITH CONTINUED MOIST FUELS. ANOTHER WEAK FRONT IS
EXPECTED TUESDAY NIGHT...BUT WILL NOT HAVE MUCH OF AN EFFECT ON
RAIN CHANCES OR TEMPERATURES. A STRONGER SYSTEM IS EXPECTED AROUND
NEXT THURSDAY WHICH COULD BRING OUR NEXT CHANCES OF RAIN...MAINLY
IN THE EASTERN COUNTIES ONCE AGAIN.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 47 68 42 60 35 / 0 0 0 20 0
AUSTIN BERGSTROM INTL AIRPORT 44 67 38 60 34 / 0 0 0 20 0
NEW BRAUNFELS MUNI AIRPORT 45 69 40 63 33 / 0 0 0 20 0
BURNET MUNI AIRPORT 43 65 40 55 33 / 0 0 0 20 0
DEL RIO INTL AIRPORT 42 71 44 65 36 / 0 0 0 - 0
GEORGETOWN MUNI AIRPORT 45 66 39 56 32 / 0 0 0 20 0
HONDO MUNI AIRPORT 44 71 42 65 34 / 0 0 0 10 0
SAN MARCOS MUNI AIRPORT 45 68 40 61 34 / 0 0 0 20 0
LA GRANGE - FAYETTE REGIONAL 50 68 42 62 34 / 10 0 - 20 -
SAN ANTONIO INTL AIRPORT 47 70 43 63 37 / 0 0 0 10 0
STINSON MUNI AIRPORT 46 71 43 64 37 / 0 0 0 10 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...ALLEN
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1032 PM CST THU JAN 14 2016
.UPDATE...BASED ON CURRENT AND EXPECTED TRENDS, PATCHY AND AREAS
OF FOG HAVE BEEN INTRODUCED ALONG THE I-35/37 CORRIDOR AND EAST
INTO THE SOUTHEAST COASTAL PLAINS. SOME LOCATIONS ACROSS FAR
SOUTHEAST COUNTIES LIKE LAVACA...FAYETTE...AND PORTIONS OF
GONZALES AND DEWITT COULD EXPERIENCE SOME AREAS OF DENSE FOG.
THIS WORDING HAS BEEN INTRODUCED INTO THE LATE EVENING AS WELL AS
THE OVERNIGHT GRIDS WILL SUPPORT FROM THE HRRR AND NAM BUFR
SOUNDINGS. A DRYLINE/PACIFIC FRONT WILL MOVE THROUGH EARLY FRIDAY
AND HELP CLEAR THE FOG BY 8 TO 9AM. NO OTHER WEATHER UPDATES WERE
MADE AND THE UPDATED ZONES ARE OUT.
&&
.PREV DISCUSSION... /ISSUED 547 PM CST THU JAN 14 2016/
AVIATION...
SOUTHERLY WINDS WILL CONTINUE TO BRING LOW LEVEL MOISTURE INTO THE
REGION THIS EVENING AND IFR CIGS WILL DEVELOP IN AUSTIN AND SAN
ANTONIO BY AROUND 03Z. A WIND SHIFT TO THE WEST OR NORTHWEST WILL
BRING IN DRIER AIR AND DRIVE OUT THE LOW CLOUDINESS AFTER 06Z TO
10Z. ALL TERMINALS WILL REMAIN VFR THROUGH THE END OF THE PERIOD.
PREV DISCUSSION... /ISSUED 236 PM CST THU JAN 14 2016/
SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
THE UPPER LEVEL LOW IS CURRENTLY CENTERED NEAR EDWARDS COUNTY AND
CONTINUES TO MOVE EAST. THE MAIN SHOWER AND THUNDERSTORM ACTIVITY
IS WELL OFF THE COAST AND CHANCES FOR RAIN FOR OUR CWA ARE FAIRLY
LOW FOR THE REST OF THE AFTERNOON. WILL CARRY NO POPS FOR THE
TONIGHT PERIOD AS ALL ACTIVITY SHOULD BE FARTHER EAST OF THE
REGION. A WEAK FRONTAL BOUNDARY IS EXPECTED TO PUSH THROUGH THE
REGION OVERNIGHT BEHIND THE DEPARTING LOW PRESSURE SYSTEM. LOWS
TONIGHT SHOULD BE IN THE 40S ACROSS MUCH OF THE AREA WITH THE
SLIGHTLY COOLER READINGS ACROSS THE NORTHWEST CWA WHERE THE FRONT
MOVES IN A BIT EARLIER. WINDS ARE EXPECTED TO RETURN TO THE SOUTH
BY TOMORROW AFTERNOON AND HIGH TEMPERATURES ARE EXPECTED TO REACH
THE UPPER 60S TO LOWER 70S. WITH DEWPOINTS REMAINING IN THE MID-
20S TOMORROW AFTERNOON...HUMIDITY VALUES WILL BOTTOM OUT IN THE
TEENS ACROSS THE WESTERN COUNTIES BUT WINDS SHOULD REMAIN BELOW 15
MPH. LOWS FRIDAY NIGHT SHOULD BE IN THE 40S ONCE AGAIN MOSTLY
CLEAR TO PARTLY CLOUDY SKIES.
LONG TERM (SATURDAY THROUGH THURSDAY)...
THE NEXT SHORTWAVE IS EXPECTED TO PUSH THROUGH THE AREA SATURDAY
MORNING. THIS SMALL BUT STRONG SYSTEM WILL BRING A SMALL CHANCE OF
RAIN TO MAINLY THE EASTERN COUNTIES SATURDAY AFTERNOON. BEHIND THE
SYSTEM WINDS WILL BE QUITE STRONG DURING THE AFTERNOON HOURS
ACROSS THE WESTERN COUNTIES. MODELS ARE SHOWING 850 WINDS OUT OF
THE NORTHWEST AROUND 40 KNOTS. SHOULD SEE ENOUGH MIXING TO HAVE
SUSTAINED 20-25 MPH WINDS AT THE SURFACE AT LEAST. SHOULD BE CLOSE
TO WIND ADVISORY CRITERIA FOR THIS AREA...BUT WILL PROBABLY JUST
BELOW THE 26 MPH SUSTAINED CRITERIA. HUMIDITY VALUES WILL BE
HIGHER THAN FRIDAY AND NOT EXPECTING MUCH OF A FIRE WEATHER ISSUE
ESPECIALLY WITH CONTINUED MOIST FUELS. ANOTHER WEAK FRONT IS
EXPECTED TUESDAY NIGHT...BUT WILL NOT HAVE MUCH OF AN EFFECT ON
RAIN CHANCES OR TEMPERATURES. A STRONGER SYSTEM IS EXPECTED AROUND
NEXT THURSDAY WHICH COULD BRING OUR NEXT CHANCES OF RAIN...MAINLY
IN THE EASTERN COUNTIES ONCE AGAIN.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 47 68 42 60 35 / 0 0 0 20 0
AUSTIN BERGSTROM INTL AIRPORT 44 67 38 60 34 / 0 0 0 20 0
NEW BRAUNFELS MUNI AIRPORT 45 69 40 63 33 / 0 0 0 20 0
BURNET MUNI AIRPORT 43 65 40 55 33 / 0 0 0 20 0
DEL RIO INTL AIRPORT 42 71 44 65 36 / 0 0 0 - 0
GEORGETOWN MUNI AIRPORT 45 66 39 56 32 / 0 0 0 20 0
HONDO MUNI AIRPORT 44 71 42 65 34 / 0 0 0 10 0
SAN MARCOS MUNI AIRPORT 45 68 40 61 34 / 0 0 0 20 0
LA GRANGE - FAYETTE REGIONAL 50 68 42 62 34 / 10 0 - 20 -
SAN ANTONIO INTL AIRPORT 47 70 43 63 37 / 0 0 0 10 0
STINSON MUNI AIRPORT 46 71 43 64 37 / 0 0 0 10 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...ALLEN
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1019 AM CST FRI JAN 15 2016
.UPDATE...
THE COLD FRONT ALREADY ARRIVED IN SOUTHERN WI THIS MORNING. BESIDES
INCREASING NORTHWEST WINDS AND GRADUALLY FALLING TEMPERATURES...
THE COLD FRONT IS MARKED BY LOW CLOUDS AND LIGHT FOG. THESE
CONDITIONS WILL PERSIST THROUGH THE AFTERNOON. CLOUD HEIGHTS WILL
RISE A BIT AND FOG SHOULD DIMINISH LATE THIS AFTERNOON INTO THE
EVENING... ALTHOUGH THERE IS A CHANCE FOR FLURRIES.
THE RAP BUFKIT SHOWS DRY AIR ABOVE 4000 FEET THROUGH THE EVENING
WHILE THE NAM KEEPS PICKING UP ON THE DEFORMATION AREA ON THE BACK
SIDE OF DEPARTING LOW PRESSURE TO PRODUCE A SHORT PERIOD OF DEEPER
SATURATION AND THUS LIGHT SNOW/FLURRIES IN THE 21 TO 02Z TIME PERIOD.
&&
.AVIATION/18Z TAFS/...
THE COLD FRONT IS BRINGING INCREASING NORTHWEST WINDS... FALLING
TEMPERATURES... LOW LOW CLOUDS BELOW 600 FEET AND REDUCED VISIBILITY
OF 3SM OR LESS TO ALL OF SOUTHERN WI LATE THIS MORNING. THE MOISTURE
DOES NOT LOOK SUFFICIENTLY DEEP TO PRODUCE DRIZZLE TODAY OR FLURRIES
UNTIL POSSIBLY LATE AFTERNOON THROUGH THE EVENING.
VSBY AND CIGS SHOULD IMPROVE TO MVFR LATE IN THE AFTERNOON. MVFR
CIGS ARE POSSIBLE THROUGH THE NIGHT... ALTHOUGH THERE ARE SIGNALS
FOR A PERIOD OF VFR OVERNIGHT BEFORE THE NEXT COLD FRONT ARRIVES MID
TO LATE SATURDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 333 AM CST FRI JAN 15 2016/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
AN UPPER LEVEL TROUGH OVER THE UPPER MISSISSIPPI VALLEY WILL
MOVE ACROSS WISCONSIN TODAY AND EXIT THE EAST EARLY THIS EVENING.
WEAK UPPER DIVERGENCE AND 700 MB UPWARD MOTION EXISTS UNTIL THE
TROUGH AXIS MOVES OFF.
THE MID LEVELS DO NOT QUITE SATURATE SO ANY PRECIPITATION WOULD
BE DUE TO THE LOW LEVEL RH INCREASE AND WEAK FORCING. THEREFORE
EXPECT MAINLY TRACE PRECIPITATION WITH THE TROUGH.
MAIN VERY SHORT TERM CONCERN IS THE DENSE FOG NEAR THE WARM FRONT
ACROSS CENTRAL WISCONSIN AND IN THE LIGHT WIND REGIME NEAR THE
SURFACE LOW.
COLD AIR ADVECTION OCCURS LATER THIS MORNING SOUTH CENTRAL AND
ACROSS SOUTHERN WISCONSIN TONIGHT.
SATURDAY AND SATURDAY NIGHT - CONFIDENCE...MEDIUM
COLD ADVECTION WILL BE ON THE INCREASE ESPECIALLY INTO THE
AFTERNOON WITH 925 TEMPS DROPPING THROUGH THE NEGATIVE TEENS
CELSIUS. A MOSTLY SHEARED VORT MAX PASSES THROUGH CENTRAL AND
SOUTHERN WI DURG THE DAY THOUGH PRIMARY VORTEX HOLDS OFF TO THE
NORTHWEST. THIS PLOWS IN SATURDAY NIGHT WITH APPRECIABLE CRASHING
OF 1000/500 MILLIBAR THICKNESS TO UNDER 500 DM. 850/925 TEMPS
DROPOFF AS WELL WITH THE BRUNT OF LOW LEVEL COLD ADVECTION. THE
NAM IS NOT AS COLD AND ALSO BRINGS LIGHT QPF INTO SRN WI WITH MORE
POTENT WAVE RIDING AROUND UPPER LOW.THE GFS AND ECMWF ARE DRY.
WILL BRING SOME SMALL POPS INTO THE SW CWA FOR NOW TO MATCH UP
WITH KARX. MAIN STORY WILL BE THE FRIGID CONDITIONS AND POTENTIAL
FOR A WIND CHILL ADVISORY.
SUNDAY - CONFIDENCE...MEDIUM
BITTERLY COLD DAY WITH DECENT PRESSURE GRADIENT AND CORE OF LOW
LEVEL THERMAL TROUGH AT ITS PEAK WITH 925 TEMPS IN THE NEGATIVE
MID 20S CELSIUS. SINGLE DIGITS SFC TEMPS EXPECTED WITH POTENTIAL
FOR SOME SPOTS TO NOT CLIMB ABV ZERO. STILL SEEING INFLUENCE OF
THE POTENT VORT MAX RIDING ON SW PERIPHERY OF THE UPPER LOW NEAR
LAKE SUPERIOR. THE NAM IS ONLY MODEL TO GENERATE QPF. WILL HOLD
OFF ON ANY SNOW MENTION WITH BUFKIT SOUNDINGS SHOWING OVERRIDING
INFLUENCE OF DRY COLUMN AND SUBSIDING INFLUENCE OF THE LOW LEVEL
COLD ADVECTION.
SUNDAY NIGHT AND MONDAY - CONFIDENCE...MEDIUM
FRIGID AIRMASS PERSISTS AS CORE OF LOWEST THICKNESSES...SUB 500DM
AND BITTERLY COLD LOW LEVEL THERMAL TROUGH REMAIN IN PLACE. SOME
SLACKENING OF THE GRADIENT THOUGH 925 WINDS REMAIN ELEVATED THOUGH
NOT AS STRONG AS SURFACE/850 RIDGE AXIS DRAW CLOSER. STILL ANOTHER
DAY WITH TEMPS LIKELY NOT REACHING DOUBLE DIGITS WITH 925 TEMPS
STILL CLOSE TO -20 CELSIUS. WIND CHILL ADVISORY LIKELY CONTINUING
FOR AT LEAST THE MORNING HOURS.
TUESDAY - CONFIDENCE...MEDIUM
COLD EASES WITH THE 500 MILLIBAR LOW WELL TO THE EAST AND SFC/850
RIDGE AXES STRETCHING FROM OH VLY INTO THE UPR MIDWEST. 925 TEMPS
MODERATE THROUGH THE NEGATIVE TEENS CELSIUS SO EXPECT TEMPS TO
REBOUND BACK TO DOUBLE DIGITS.
TUESDAY NIGHT AND WEDNESDAY - CONFIDENCE...MEDIUM
GFS/ECWMF TAKE POSITIVE TILT SHORTWAVE SOUTH OF THE AREA WITH
BOTH MODELS GRAZING THE AREA WITH SOME LIGHT QPF FROM THIS
FEATURE. SUPERBLEND POPS SHOW SLGT CHCS. THE GEM SHOWS THIS AS A
MORE ELONGATED/SHEARED FEATURE THOUGH SHOWS A BIT MORE ISENTROPIC
FEATURE AND ACTUALLY MORE OF A QPF SIGNAL THAN THE ECMWF. THE
SUPERBLEND POPS SHOW SLGT CHCS AND WILL RETAIN THESE IN THE
GRIDS.
THURSDAY - CONFIDENCE...LOW
MODEL DIFFERENCES WITH HANDLING OF SHORTWAVE ENERGY RIDING ACRS
ERN SIDE OF WRN RIDGE. THE ECMWF SHOWS A MORE AMPLIFIED WAVE WHILE
THE GFS SHOWS A MORE QUICK HITTING VORT. SUPERBLEND POPS ARE
LEANING DRY.
AVIATION/12Z TAFS/...AREAS OF LIFR FOG AHEAD OF AN AREA OF LOW
PRESSURE... CENTERED OVER SOUTHWEST/WEST CENTRAL WISCONSIN THAT
PUSHES EAST.
CONFIDENCE IS LOW ON THE POTENTIAL FOR DRIZZLE TO DEVELOP MORE TO
THE SOUTH THIS MORNING. THIS MOIST LAYER LOOKS TO DEEPEN AFTER
SUNRISE. MVFR AND IFR CIGS EXPECTED ESPECIALLY AFTER THE COLD
FRONTAL PASSAGE.
MARINE...A SMALL CRAFT ADVISORY IS IN EFFECT LATER THIS
AFTERNOON INTO SATURDAY AFTERNOON AS GUSTY NORTHWEST WINDS DEVELOP
BEHIND AN EXITING LOW PRESSURE SYSTEM. HIGH WAVES SHOULD DEVELOP
TOWARD THE OPEN WATERS...AS WELL AS THE POSSIBILITY OF SOME
FREEZING SPRAY AS MUCH COLDER AIR MOVES ACROSS THE GREAT LAKES.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 2 PM CST
SATURDAY FOR LMZ643>646.
&&
$$
UPDATE...MRC
TODAY/TONIGHT AND AVIATION/MARINE...HENTZ
SATURDAY THROUGH THURSDAY...COLLAR
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
238 PM MST FRI JAN 15 2016
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 239 PM MST FRI JAN 15 2016
MODELS CONTINUE TO STRUGGLE WITH THE PLACEMENT OF SEVERAL BANDS OF
PRECIPITATION IN THE SHORT TERM...IN ADDITION TO THE ARCTIC FRONT
SATURDAY/SATURDAY NIGHT AND HOW FAR WEST IT STALLS. FOR THIS
AFTERNOON...SNOW IS GRADUALLY TAPERING OFF TO SNOW FLURRIES
ACROSS CARBON COUNTY AFTER THE LOCALLY HEAVY SNOW SHOWERS FROM
EARLIER THIS MORNING. EXPECT A BRIEF LULL INTO LATE THIS AFTERNOON
BEFORE A VORTICITY MAX ASSOCIATED WITH AN UPPER LEVEL DISTURBANCE
PUSHES SOUTHEAST ACROSS SOUTHEAST WYOMING THIS EVENING. THERE IS
SOME GOOD LLVL INSTABILITY FOR THIS TIME OF THE YEAR AS WELL AS
SOME FRONTOGENESIS ALONG THE LARAMIE RANGE...AND ALONG AND SOUTH
OF I80. THE TRICKY PART IS...IF THIS BAND OF SNOW DEVELOPS FURTHER
SOUTH INTO COLORADO...THE I80 CORRIDOR MAY RECEIVE NOTHING OUTSIDE
OF A FEW FLURRIES. INCREASED POP BETWEEN 40 TO 80
PERCENT...HIGHEST IN THE MOUNTAINS. WILL NEED TO KEEP AN EYE ON
THE I80 SUMMIT AS WELL AS LARAMIE AND CHEYENNE FOR ACCUMULATING
SNOW AND SOME IMPACTS TO ROADS THIS EVENING. SOME OF THESE SNOW
BANDS MAY BE MODERATE TO HEAVY AT TIMES IN INTENSITY.
SATURDAY...ARCTIC FRONTAL BOUNDARY STILL PROJECTED TO MOVE
SOUTHWARD AND JAM UP EAST OF THE LARAMIE RANGE ON SATURDAY. DECENT
FRONTAL FORCING ALONG AND EAST OF THE LARAMIE RANGE WITH AMPLE
MOISTURE AND INSTABILITY EXPECT TO GET A FAIRLY DECENT COVERAGE OF
SNOW SHOWERS IN BANDS ACROSS SOUTHEAST WYOMING AND EAST INTO THE
NEBRASKA PANHANDLE SATURDAY INTO SATURDAY NIGHT AS ANOTHER
SHORTWAVE MOVES THROUGH. OUT WEST FAVORABLE ACTIVE NORTHWESTERLY
FLOW WITH UPSLOPE WILL KEEP SNOW GOING IN THE MOUNTAINS WELL INTO
THE WEEKEND. AN ADDITIONAL 12 TO 18 INCHES OF SNOW CAN BE EXPECTED
FOR A 3 DAY WEEKEND TOTAL ABOVE 9500 FT IN THE SIERRA MADRE RANGE
WITH 8 TO 12 INCHES ABOVE 9500 FT FOR THE SNOWY RANGE. LOWER 24
HOUR TOTALS IN THE MOUNTAINS WILL KEEP THE EVENT IN THE ADVISORY
CATEGORY. WILL NEED TO MONITOR FOR POSSIBLE ADDITION OF A WINTER
WEATHER ADVISORY FOR THE SNOWY RANGE AS WELL FOR SATURDAY INTO
SUNDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 239 PM MST FRI JAN 15 2016
SNOW SHOWERS TAPER OFF BY SUNDAY AFTERNOON IN THE LOWER ELEVATIONS
WITH SNOW CONTINUING IN THE MOUNTAINS THROUGH WEDNESDAY GIVEN
FAVORABLE AND ACTIVE MIDLEVEL FLOW. AFTER A COUPLE OF SHORTWAVES
MOVE THROUGH MONDAY INTO WEDNESDAY...IT APPEARS WE DRY OUT
SUFFICIENTLY TO NEGATE POPS THURSDAY INTO NEXT WEEKEND AS A
RATHER LARGE AMPLITUDE MID/UPPER RIDGE TRAVERSES THE
CENTRAL/NORTHERN ROCKIES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1017 AM MST FRI JAN 15 2016
CONFIDENCE INCREASING THAT SNOW IS GOING TO IMPACT SEVERAL
AIRPORTS IN SOUTHEAST WYOMING AND POSSIBLY THE NORTHERN NEBRASKA
PANHANDLE. HRRR GUIDANCE SHOWING A CLIPPER SYSTEM OVER
NORTHEASTERN WYOMING MOVING SOUTHEAST BRINGING SNOW AND LOWERING
CONDITIONS TO KCDR AND KAIA. MAINLY AFTER 00Z...BUT COULD SEE IT A
LITTLE SOONER. FOR THE I-80 CORRIDOR FROM CHEYENNE TO
RAWLINS...LOOKING AT DETERIORATING CONDITIONS THROUGH THE
AFTERNOON WITH MAIN IMPACTS OUTSIDE OF KRWL AFTER 00Z AS WELL.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS ARE EXPECTED AT THIS TIME DUE TO SNOW
COVER IN PLACE AND COLDER AIR MOVING INTO AREAS EAST OF THE
LARAMIE RANGE SATURDAY NIGHT INTO SUNDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 5 AM MST SATURDAY FOR WYZ112.
NE...NONE.
&&
$$
SHORT TERM...TJT/JG
LONG TERM...JG
AVIATION...GCC/JG
FIRE WEATHER...REC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1021 AM MST FRI JAN 15 2016
.UPDATE...
ISSUED AT 944 AM MST FRI JAN 15 2016
SEVERAL FORECAST CONCERNS THIS MORNING THROUGH SATURDAY NIGHT AS
AN ARCTIC AIRMASS SETTLES OVER THE EASTERN PLAINS. BRIEF MODERATE
TO HEAVY SNOW SHOWERS SHOULD BE ENDING SHORTLY FURTHER WEST
BETWEEN LARAMIE AND RAWLINS AS VISIBILITIES SEEM TO HAVE INCREASE
A BIT ALONG I-80. EXPECT A BRIEF LULL THIS AFTERNOON BEFORE
ANOTHER BAND OF MODERATE TO HEAVY SNOW IS POSSIBLE FURTHER EAST
ALONG I-80...THIS TIME POTENTIALLY IMPACTING
LARAMIE...CHEYENNE...AND FURTHER EAST TOWARDS SOUTHERN NEBRASKA.
12Z MODELS HAVE STARTED TO COME IN AND SHOW THE POTENTIAL FOR
BANDED SNOW SOMEWHERE ALONG AND SOUTH OF I-80 THIS EVENING DUE TO
LLVL INSTABILITY AND FRONTOGENESIS ALONG THE LARAMIE RANGE. NOT
CONFIDENT ENOUGH ABOUT THE IMPACTS TO ISSUE A WINTER WEATHER
ADVISORY...BUT NEED TO KEEP AN EYE ON THIS THROUGH THE AFTERNOON.
12Z GFS HAS TRENDED MORE AGGRESSIVE WITH SNOWFALL SATURDAY NIGHT
AS THE ARCTIC FRONT STALLS ALONG THE LARAMIE RANGE. THE OTHER
MODELS HOWEVER ARE SHOWING LITTLE IF ANY SNOWFALL ASSOCIATED WITH
THE FRONT ACROSS THE HIGH PLAINS...SO CONFIDENCE REMAINS LOW AT
THIS TIME OUTSIDE THE MOUNTAINS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 307 AM MST FRI JAN 15 2016
THE MAIN CONCERN WITH THIS PORTION OF THE FORECAST IS THE SNOW
POTENTIAL IN THE MOUNTAINS TODAY AND TONIGHT AND LIGHT SNOW
MOVING THROUGH THE WYOMING PLAINS TONIGHT.
TODAY:
LATEST RADAR/IR LOOP WAS SHOWING THE LIGHT SNOW BEGINNING
TO DIMINISH IN NATRONA COUNTY. HOWEVER...THE BANDING OF SNOW WAS
BEGINNING TO INCREASE ACROSS CONVERSE COUNTY. THE MODELS WERE
SHOWING RISING THETA SURFACES IN THE LOW LEVELS THIS MORNING. THIS
WAS HELPING STEEPEN THE LOW LEVEL LAPSE RATES AND YIELDING TO SOME
UNSTABLE CONDITIONS IN THAT REGION THIS MORNING. LATEST WEBCAMS
WERE SHOWING SOME SNOW COVERED ROADS AROUND DEER CREEK ROAD AND
POINTS WEST AS YOU HEAD TO CASPER. THE RAP/NAM SHOWS THE
SUBSIDENCE MOVING INTO THE PICTURE BY 15Z OR SO. THEREFORE...WE
DECIDED TO KEEP A CHANCE OF SNOW THIS MORNING WHICH MAY KEEP
THINGS SLICK DURING THE MORNING COMMUTE. WE ARE ALSO BEGINNING TO
SEE THE SNOW ENHANCE NEAR THE WY/NE BORDER. WEBCAMS WERE NOT
SHOWING MUCH ACCUMULATION WITH THIS SNOW DUE TO WEAK LIFT AND LACK
OF LOW LEVEL MOISTURE. MEANWHILE...THE MAIN SHOW WAS IN NORTHWEST
COLORADO WHERE THE BULK OF THE UPPER LEVEL FORCING WAS IN PLACE.
HOWEVER...OUR MOUNTAIN RANGES SHOULD BEGIN TO SEE SOME ENHANCEMENT
AS THE MORNING WEARS ON IN RESPONSE TO THE UPPER LEVEL DIVERGENCE
AND UPSLOPE FLOW. THE SNOW MAY EVEN BE QUITE HEAVY AT TIMES THIS
AFTERNOON AND THIS EVENING DUE TO DECENT LOW LEVEL LAPSE RATES
WITH ADDITIONAL ACCUMULATION OF 3 TO 6 INCHES.
TONIGHT-SATURDAY:
ANOTHER POTENTIAL VORTICITY ANOMALY IS EXPECTED TO PUSH INTO
SOUTHERN WYOMING FROM THE WEST THIS AFTERNOON WHICH MAY HELP
STEEPEN LOW LEVEL LAPSE RATES TO AROUND 8 DEG C/KM. THIS COULD
RESULT IN SOME SNOW SHOWERS ALONG THE I-80 CORRIDOR IN SOUTHERN
WYOMING LATE THIS AFTERNOON AND EVENING. AS A RESULT...WE COULD
SEE SOME BRIEF REDUCED VISIBILITIES IF THIS BANDED SNOWFALL
DEVELOPS. DAYSHIFT WILL CERTAINLY NEED TO MONITOR THIS POTENTIAL.
THE GOOD THING IS THAT IT SHOULD BE RATHER SHORTLIVED AND WIND
SPEEDS WILL BE FAIRLY LIGHT THIS AFTERNOON. THE SNOW SHOULD ALSO
BEGIN TO TAPER OFF IN THE MOUNTAINS TONIGHT.
SATURDAY NIGHT-SUNDAY NIGHT:
THE MODELS ARE ADVERTISING (ESPECIALLY THE ECMWF) THAT COLDER AIR
WILL BEGIN TO FILTER INTO THE NEBRASKA PANHANDLE ON SATURDAY NIGHT
AS A COLD FRONTAL BOUNDARY SLIDES INTO THAT REGION. THIS BOUNDARY
WILL BRING SOME LIGHT SNOW WITH IT...BUT ACCUMULATIONS ARE
EXPECTED TO BE LIGHT (1 INCH OR LESS). THERMAL CONTRAST ALONG THIS
BOUNDARY COULD BE QUITE EXTREME WITH A NEARLY 20 TO 30 DEGREE
CHANGE. THE MAIN QUESTION WILL BE HOW FAR WEST THIS BOUNDARY CAN
PENETRATE. WE FAVORED THE ECMWF SOLUTION WHICH TENDS TO HANDLE
THESE AIR MASSES THE BEST AND BRINGS THE BOUNDARY AS FAR WEST AS
THE WYOMING BORDER. WE MAY BE LOOKING AT LOW TEMPERATURES BELOW
ZERO IN PARTS OF THE PANHANDLE ON SATURDAY NIGHT AND SUNDAY NIGHT.
MEANWHILE...AREAS WEST OF THE LARAMIE RANGE MAY SEE STRONG WINDS
DEVELOP AGAIN IN RESPONSE TO A TIGHTENING 800-700MB HEIGHT
GRADIENT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 307 AM MST FRI JAN 15 2016
SOMEWHAT UNSETTLED WEATHER SEEN ACROSS THE CWA THIS PERIOD IN A
PROGRESSIVE UPPER PATTERN WITH AT LEAST A COUPLE SHORTWAVES
PASSING ACROSS THE REGION. ONE WILL APPROACH THE CWA LATE MONDAY
SPREADING SOME SNOW SHOWERS TO MAINLY THE HIGHER MTNS MONDAY
AFTERNOON THEN MORE SCTD ACTIVITY REACHING OUT OVER THE PLAINS
MONDAY NIGHT ALONG WITH A PACIFIC COLD FRONT PASSING ACROSS THE
AREA. COLDER AND MAINLY DRY TUESDAY AND TUESDAY NIGHT BEFORE THE
NEXT UPPER SHORTWAVE PASSES THROUGH THE REGION WEDNESDAY. EC MORE
AMPLIFIED WITH THIS SYSTEM AS OPPOSED TO THE GFS WHICH BASICALLY
DAMPS IT OUT ON THE FRONT SIDE OF AN UPPER RIDGE OVER THE WESTERN
CONUS. BEST CHANCE FOR SNOW SHOWERS AGAIN OVER THE HIGHER MTNS BUT
WILL KEEP SOME MENTION OF PCPN OVER THE PLAINS. DRY AND MILDER
AGAIN FOR THURSDAY AS THE UPPER RIDGE SHIFTS EAST AND OVER THE
REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1017 AM MST FRI JAN 15 2016
CONFIDENCE INCREASING THAT SNOW IS GOING TO IMPACT SEVERAL
AIRPORTS IN SOUTHEAST WYOMING AND POSSIBLY THE NORTHERN NEBRASKA
PANHANDLE. HRRR GUIDANCE SHOWING A CLIPPER SYSTEM OVER
NORTHEASTERN WYOMING MOVING SOUTHEAST BRINGING SNOW AND LOWERING
CONDITIONS TO KCDR AND KAIA. MAINLY AFTER 00Z...BUT COULD SEE IT A
LITTLE SOONER. FOR THE I-80 CORRIDOR FROM CHEYENNE TO
RAWLINS...LOOKING AT DETERIORATING CONDITIONS THROUGH THE
AFTERNOON WITH MAIN IMPACTS OUTSIDE OF KRWL AFTER 00Z AS WELL.
&&
.FIRE WEATHER...
ISSUED AT 307 AM MST FRI JAN 15 2016
NO FIRE WEATHER CONCERNS ARE EXPECTED AT THIS TIME DUE TO SNOW
COVER IN PLACE AND COLDER AIR MOVING INTO AREAS EAST OF THE
LARAMIE RANGE SATURDAY NIGHT INTO SUNDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER WEATHER ADVISORY UNTIL 5 AM MST SATURDAY FOR WYZ112.
NE...NONE.
&&
$$
UPDATE...TJT
SHORT TERM...REC
LONG TERM...RE
AVIATION...GCC
FIRE WEATHER...REC
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
140 AM MST SUN JAN 17 2016
.SYNOPSIS...
HIGH PRESSURE OVER THE WESTERN STATES WILL FLUCTUATE IN STRENGTH BUT
OVERALL KEEP ANY WEATHER SYSTEMS TO THE NORTH OF ARIZONA. TEMPERATURES
WILL WARM THIS WEEKEND PEAKING A BIT ABOVE NORMAL BY MONDAY...AND
REMAINING NEAR OR SLIGHTLY ABOVE SEASONAL NORMALS THROUGH NEXT
FRIDAY. DISTURBANCES PASSING THROUGH THE RIDGE WILL BRING PERIODS OF
MAINLY HIGH CLOUDS LEADING TO PARTLY SUNNY OR EVEN MOSTLY CLOUDY
SKIES AT TIMES.
&&
.DISCUSSION... AT 2 AM A FAST MOVING SHORT WAVE RIDING THROUGH AN
UPPER RIDGE CONTINUED TO PUSH EAST AND INTO NEW MEXICO. THIS SYSTEM
BROUGHT LITTLE IF ANY PRECIP TO THE AREA BUT DID USHER IN QUITE A
BIT OF THICK MID AND HIGH CLOUD COVER...SOME OF WHICH STILL LINGERS
OVER THE LOWER DESERTS AS SEEN IN THE CURRENT IR SATELLITE IMAGERY.
THE CLOUDS YESTERDAY KEPT HIGH TEMPS DOWN SEVERAL DEGREES ACROSS
SOUTH CENTRAL ARIZONA AND PHOENIX ONLY REACHED TO 62 DEGREES...WHICH
IS 5 DEGREES BELOW SEASONAL NORMALS.
THE LARGE SCALE WEATHER PATTERN THROUGH THE WEEK AND INTO THE
WEEKEND LOOKS TO BE A DRY ONE FOR SERN CA AND SRN ARIZONA AS IT WILL
BE DOMINATED BY LARGE SCALE RIDGING EACH DAY. THERE WILL BE A SERIES
OF SHORT WAVES MOVING THROUGH THE FLOW...TWO OF THE MORE PROMINENT
ONES WILL PASS BY MONDAY/MONDAY NIGHT AND TUESDAY NIGHT INTO EARLY
WEDNESDAY. THESE SYSTEMS WILL PRODUCE LITTLE IF ANY PRECIP...AND
POPS ALL WEEK WILL STAY IN THE SINGLE DIGITS. HOWEVER...THE CLOUDS
WILL USHER IN PERIODS OF THICK MID AND HIGH CLOUDS WHICH WILL SERVE
TO MODERATE OUR HIGH TEMPERATURES A BIT AND KEEP OUR LOWS ON THE
MILD SIDE. FOR THE MOST PART HIGH TEMPERATURES EACH DAY WILL STAY
NEAR OR SLIGHTLY ABOVE SEASONAL NORMALS WITH THE WARMER DESERTS
OCCASIONALLY CLIMBING INTO THE LOWER OR EVEN MIDDLE 70S. THE WARMEST
DAYS THIS WEEK ARE EXPECTED TO BE THURSDAY AND FRIDAY...AS HIGH
PRESSURE ALOFT WILL BE THE STRONGEST ON THOSE DAYS.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NO SIGNIFICANT AVIATION IMPACTS THROUGH SUNDAY EVENING WITH ONLY
PERIODS OF THICKER HIGH CLOUDS (ABOVE 15K FT) OVER THE REGION. SFC
WINDS WILL REMAIN VERY LIGHT AOB 8KT...AND WILL BE VARIABLE OR CALM
FOR EXTENDED PERIODS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
HIGH PRESSURE WILL GENERALLY REMAIN IN PLACE OVER THE INTERIOR WESTERN
STATES GETTING WEAKENED FROM TIME TO TIME BY STORMS THAT PASS TO OUR
NORTH...ONLY BRUSHING ARIZONA AND SOUTHEAST CALIFORNIA. CHANCES FOR
ANY WETTING RAINS DURING THE WEEK WILL BE SLIM. HUMIDITIES INCREASE
BY WEDNESDAY DUE TO A PASSING WEATHER DISTURBANCE. THIS WILL BE
FOLLOWED BY DECLINING HUMIDITIES BUT REMAINING ABOVE 20 PERCENT.
OVERNIGHT RECOVERY REMAINS GOOD. TEMPERATURES WILL REMAIN NEAR NORMAL
THE FIRST HALF OF THE WEEK FOLLOWED BY A FEW DEGREES OF WARMING
DURING THE LATTER HALF. WINDS ON THE VALLEY FLOORS WILL REMAIN
LIGHT...OCCASIONAL BREEZINESS AT RIDGETOPS...FAVORING NORTH AND EAST
DIRECTIONS.
&&
.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...CB
AVIATION...MO
FIRE WEATHER...AJ
[top]
Area Forecast Discussion
National Weather Service Sacramento CA
1015 PM PST SAT JAN 16 2016
.SYNOPSIS...
WET SYSTEM MOVING IN SUNDAY THROUGH EARLY MONDAY. SOME SMALL
SCALE AND/OR BURN SCAR FLOODING COULD OCCUR DURING THIS TIME.
EXPECT PERIODS OF PRECIPITATION THROUGH NEXT WEEK.
&&
.DISCUSSION...
Impressive moisture plume coming into view on satellite just off
the west coast. 00z model runs and short term HRRR all trending a
few hours slower with the system...but also wetter as they have
the heavier band stalling out into Monday morning. Heaviest
rain band will move into the north valley around 5am and sag
south to the southern valley by 7pm Sunday. Numerous showers will
develop ahead of this band and should begin over the north valley
after midnight and spread south Sunday morning.
In the near term, isolated areas of fog have developed especially
over the delta where KSUU and KVCB have occasionally went under a
mile. Not expecting this to last through the night...as cloud
cover and mixing with incoming system should improve conditions.
&&
.PREVIOUS DISCUSSION...
A series of storms will move through the region through Tuesday.
The current system is exiting the region with shower chances
continuing into the evening. Snow levels have been risen up to
around 7500 feet and will remain high through Tuesday but may dip
at times below major pass levels of US-50 and I-80. I have
modified the flash flood watch period to when the heavier rain is
expected to move through Lake County for Sunday afternoon and
evening. Timing of the later system on Tuesday may change a
little.
In the shorter term the NAM and HRRR models are indicating showers
enhancing around mid afternoon over the Southern Sacramento
Valley and Western Slopes of the Sierra Nevada. Showers should
taper some this evening then rain may start for places around I-80
and to the north later tonight and Sunday morning. The heaviest
rainfall is expected Sunday afternoon and evening. Sunday evening
snow levels look like they may lower below major Sierra pass
levels and have some impact on travel.
&&
.EXTENDED DISCUSSION (Wednesday THROUGH Saturday)
Unsettled weather pattern will continue through next week as
several storms move into NorCal from the Pacific. Forecast timing
will likely fluctuate over the next several runs under this
progressive pattern, but confidence is high in both a midweek and
late-week storm over the region. Snow levels will generally remain
around 5000-7000 feet before lowering next weekend. Temperatures
will be close to average for mid-January.
Dang
&&
.AVIATION...
Wly flow alf as upr rdg movs thru tngt...bckg to SWly Sun as nxt
Pac fntl sys movs into Intr NorCal. For Cstl/Shasta mtns and
Cntrl Vly...lcl MVFR/IFR bcmg wdsprd MVFR with areas IFR aft 12z
Sun. Ovr Wrn Plumas/Siernev lcl MVFR bcmg wdsprd MVFR/IFR with lcl
LIFR aft 17z Sun. Sn lvls genly aoa 055 msl. Lcl SEly sfc wnd gsts
to 30 kts Sun with SWly sfc wnd gsts to 40 kts poss ovr hyr mtn
trrn.
&&
.STO Watches/Warnings/Advisories...
Flash Flood Watch from Sunday afternoon through Sunday evening
for Clear Lake/Southern Lake County-Mountains Southwestern
Shasta County to Northern Lake County.
&&
$$
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
331 AM CST SUN JAN 17 2016
.SHORT TERM...(Today)
ISSUED AT 331 AM CST SUN JAN 17 2016
Arctic high pressure will continue to slowly build into central and
southeast Illinois today. Some bands of light snow should continue
to accompany the leading edge of the very cold air this morning, but
it is not expected to amount to more than a dusting.
The most notable weather element today will be the cold condtions.
Temperatures at 3 AM range from the single digits in the far
northern portion of the forecast area, to the lower 20s along and
south of I-70. Temperatures are well below zero not too far upstream
across Iowa. Colder air will continue to spill across the area today
on persistent northwest winds. Do not expect much temperature
recovery today across the northern portion of the forecast area
despite developing sunshine by afternoon. Meanwhile, the "milder"
temperatures across the southern portion of the forecast area should
continue to fall. Wind Chill values will stay near advisory levels
across far northern portion of the area this morning, and will keep
Wind Chill Advisory in place there. Further south, where advisory
criteria will not be met, it will still be a very chilly day.
&&
.LONG TERM...(Tonight through Saturday)
ISSUED AT 331 AM CST SUN JAN 17 2016
Another wind chill advisory will be issued for central IL north of
I-70 tonight and Monday morning, with wind chills lowering to 15-25F
below zero during this evening and continue into late Monday
morning. Lows tonight to range from around 5F below zero northern
CWA to 0-5F above in southeast IL. Another frigid day Monday despite
ample sunshine with highs 10-15F. NW winds 10-15 mph and gusts to 20
mph prevail tonight and Monday. Lows Monday night range from zero to
7 above zero, and lighter winds to keep wind chills from getting as
cold, with northern areas reaching near 10 below wind chills. Highs
Tue reach 20-25F with increasing clouds.
Arctic airmass due to 1034 mb Canadian high pressure dropping
southward into the Northern Plains and to move into the MS river
valley Monday night, and into the OH/TN river valleys Tue. This to
bring the coldest air of the season to central and southeast IL. Dry
conditions expected across the area from tonight through much of
Tuesday, though a slight chance of light snow west of a Canton to
Springfield line by late Tue afternoon.
A stronger disturbance than this mornings will track into the
central plains Tue and into the MS river valley Tue night, and then
into the OH river valley Wed. Models have trended a bit higher with
snowfall amounts with 2-3 inches Tue night into Wed morning versus 1-
2 inches with yesterdays runs. Highest amounts are sw of I-74. May
evenually need a winter weather advisory for snow if this trend
continues. Any mixed precipitation should stay well south of I-64
over far southern IL with this system.
00Z models continue to struggle with southern stream storm system
late this week. ECMWF model continues to keep qpf south of central
and southeast IL Thu/Fri with surface low moving into the TN river
valley Thu night. More aggressive GEM models brings qpf across IL
during the day Thu and then diminishes from the west during day Fri
with surface low moving up the Ohio river. GFS models is inbetween
with qpf into southeast IL from I-70 south from Thu afternoon into
early Friday. Will stay close to ensemble concensus with keeping 20-
30% chances of light snow from Thu afternoon through Fri morning
with highest pops in southeast IL and IL river valley/nw IL drier.
Mixed precipititation could get into southern counties if pcpn gets
this far north. Temps to gradually modify late this week into next
weekend as highs reach the mid 30s to lower 40s next weekend as
upper level ridge builds into the area by Saturday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1146 PM CST SAT JAN 16 2016
Light snow/flurries are occurring along the arctic cold front as
it pushes southeast across central IL. The relatively dry air
below the cloud layer is reducing the potential for measurable
snow. Radar trends show that the flurries will likely linger until
a shortwave moves across Illinois after midnight. HRRR and RAP are
downplaying the snowfall coverage, as are the NAM and GFS. Radar
loops show precip steadily approaching, so will keep very light
snow in the TAFs for the remainder of the night, but overall
impact will be minimal due to limited snow accumulation if any.
Will keep all TAFs only as low as MVFR clouds, as upstream IFR
conditions seem to be maintaining a path to the SW of our
counties. Snowfall chances could linger through the morning hours,
but all precip should end by midday as the very dry airmass
arrives on brisk NW winds.
Winds will shift from W to NW after the passage of the arctic
front, with speeds increasing later tonight as pressure rises ramp
up in the wake of the front. By 12z, winds could already be
gusting to 25kt in PIA, with those gusts advancing to CMI/DEC by
14z.
Forecast soundings show clearing skies progressing into the area from
the northwest Sunday afternoon, with clear conditions at all TAF
sites by mid-afternoon.
&&
.ILX Watches/Warnings/Advisories...
Wind Chill Advisory from 6 PM this evening to 11 AM CST Monday
for ILZ027>031-036>038-040>057-061.
Wind Chill Advisory until 11 AM CST this morning for ILZ027>031-
036-037.
&&
$$
SHORT TERM...BAK
LONG TERM...07
AVIATION...Shimon
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1146 PM CST SAT JAN 16 2016
.UPDATE...
ISSUED AT 910 PM CST SAT JAN 16 2016
The arctic front is progressing southeast across IL, with a band
of flurries developing along the front northwest of a line from
Rushville to Lincoln to Bloomington at 03z/9pm. The 00z ILX
sounding showed some dry air to overcome, so the radar returns may
be mostly virga at this point. Have added flurries to follow the
band of radar returns as it progresses farther southeast. The
initial period of snow is expected to dissipate according to HRRR
and RAP output, with another wave of snow developing with an upper
level wave moving east along the front. High res models show that
wave of snow will be mainly in our western counties, with somewhat
limited eastward extent. Have delayed the coverage of chance PoPs
with the second wave, and lowered the extent of the 50 pct PoPs.
A dusting of snow still could develop in a few locations, but the
increasing wind will likely push most of that snow off area roads.
Updates this evening were mainly needed for the weather and PoP
grids. Temps and winds look on track, so will not make any
adjustments to the wind chill advisory for our NW
counties...mainly NW of the IL river. Updated forecast info is
already available.
&&
.SHORT TERM...(Tonight)
ISSUED AT 255 PM CST SAT JAN 16 2016
A surge of bitterly cold air is on the way later tonight...as a
1033mb high over Saskatchewan builds southward into the central U.S.
An area of lift ahead of the colder airmass associated with a weak
mid-level short-wave is spreading across eastern Nebraska into
western/central Iowa, where light snow is currently falling. Models
show this lift gradually developing eastward into central Illinois
later this evening into the overnight hours. Airmass will initially
be quite dry at mid/low-levels, so it will take awhile for any
precip to develop. Based on time-height cross-sections, it appears
strongest lift and deepest column moisture will only be present for
a 3-4 hour window from just after midnight into Sunday morning. Have
therefore kept conditions dry through the evening, with high chance
PoPs for light snow developing along/north of the I-72 corridor
after midnight. Accumulations will be minor due to the light and
transient nature of the precip, with amounts of one half inch or
less anticipated. Main weather story will be the breezy and colder
conditions, as overnight lows drop into the single digits and teens.
Corresponding wind-chill values will drop below zero along/north of
I-72 by dawn Sunday...with the coldest readings of near 15 below
zero across the NW KILX CWA. Have issued a Wind Chill Advisory
along and north of a Lewistown to El Paso line...and a Special
Weather Statement highlighting the cold further southeast to I-72.
.LONG TERM...(Sunday through Saturday)
ISSUED AT 255 PM CST SAT JAN 16 2016
A weak wave will continue to move across the area Sunday morning,
with light amounts of snowfall expected. Due to the weak lift and
limited moisture, will continue with just chance pops for the
morning only and then have dry weather with skies clearing out in
the afternoon. This dry weather will continue thru the rest of the
weekend holiday and into Monday night. Then clouds will begin to
increase on Tuesday as the next weather system approaches from the
west. The mid range models are in very good agreement with this next
system with snow expected Tue afternoon through Wed morning/early
afternoon. Based on timing of the low pressure area the best chance
of snow will be Tuesday night and in southwest IL. Though this
system is stronger than the one coming in tonight and it will have
more moisture to work with, it doesn`t appear that much snow will
occur with this system. A couple of inches will be possible, but
over a period of 24-30hrs. Another weather system is possible on the
heals of the system that will be leaving the area Wed. However,
models showing disagreement with track of low pressure area, which
effects the location and timing of pcpn. ECMWF takes the sfc low
well south, into the Gulf Coastal area and moves it east across FL.
The GFS and Canadian are in agreement with each other and bring the
sfc low out of OK, through southern MO, and into southern IL. This
track would spread more pcpn/snow across the CWA for the later part
of the week. So will continue with a blend of models with this end
of week system and have chance pops only Thur night across areas
east of the IL river, only. Will have just snow in the forecast for
now, but this looks like an over-running situation, so a wintry mix
of pcpn is not out of the question. New forecasts early next week
should give us a better idea on location and pcpn type.
Temps will be very cold tonight and tomorrow night. Wind chill
advisory for tonight will continue til tomorrow late morning in the
northwest. However, with temps expected to be even colder tomorrow
night/Mon morning, another advisory is likely and will probably
cover the entire CWA. Temps will gradually warm next week and could
reach to normal by next Sat.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1146 PM CST SAT JAN 16 2016
Light snow/flurries are occurring along the arctic cold front as
it pushes southeast across central IL. The relatively dry air
below the cloud layer is reducing the potential for measurable
snow. Radar trends show that the flurries will likely linger until
a shortwave moves across Illinois after midnight. HRRR and RAP are
downplaying the snowfall coverage, as are the NAM and GFS. Radar
loops show precip steadily approaching, so will keep very light
snow in the TAFs for the remainder of the night, but overall
impact will be minimal due to limited snow accumulation if any.
Will keep all TAFs only as low as MVFR clouds, as upstream IFR
conditions seem to be maintaining a path to the SW of our
counties. Snowfall chances could linger through the morning hours,
but all precip should end by midday as the very dry airmass
arrives on brisk NW winds.
Winds will shift from W to NW after the passage of the arctic
front, with speeds increasing later tonight as pressure rises ramp
up in the wake of the front. By 12z, winds could already be
gusting to 25kt in PIA, with those gusts advancing to CMI/DEC by
14z.
Forecast soundings show clearing skies progressing into the area from
the northwest Sunday afternoon, with clear conditions at all TAF
sites by mid-afternoon.
&&
.ILX Watches/Warnings/Advisories...
Wind Chill Advisory from 3 AM to 11 AM CST Sunday for ILZ027>031-
036-037.
&&
$$
UPDATE...Shimon
SHORT TERM...Barnes
LONG TERM...Auten
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS JACKSON KY
1255 AM EST SUN JAN 17 2016
.UPDATE...
ISSUED AT 1256 AM EST SUN JAN 17 2016
UPDATED TO KEEP TEMPERATURES MORE STEADY THROUGH THE REST OF THE
NIGHT AS WE SHOULD SEE VERY LITTLE FALL FROM CURRENT READINGS.
ALSO...STILL SEEING SOME RETURNS ON JKL RADAR TO SUPPORT KEEPING
THE MENTION OF DRIZZLE/FLURRIES IN THE FORECAST THROUGH THE REST
OF THE NIGHT...BASICALLY ACROSS FAR EASTERN AND SOUTHEAST
KENTUCKY. HRRR AND OTHER SHORT TERM MODEL GUIDANCE CONTINUES TO
BRING IN SOME LIGHT SNOW ACROSS FAR SOUTHEAST KENTUCKY LATE
TONIGHT. LOOKS LIKE THERE WILL ONLY BE A FEW HOUR WINDOW RIGHT
AROUND DAYBREAK FOR SNOWFALL TO OCCUR. WITH THIS IN MIND...DID
TWEAK SNOWFALL AMOUNTS TO MATCH THE EXPECTED QPF WHICH SHOULD
REMAIN VERY LIGHT. THUS...SNOWFALL WILL REMAIN UNDER A HALF INCH.
UPDATE ISSUED AT 1052 PM EST SAT JAN 16 2016
THE LIGHT WINTRY PRECIP HAS GENERALLY BECOME MORE CELLULAR OR
SHOWERY OVER THE PAST FEW HOURS. CLOUD TOP TEMPS SUGGEST THAT THIS
IS EITHER FLURRIES OR LIGHT SNOW SHOWERS FOR THE MOST PART...BUT
SOME FREEZING DRIZZLE STILL CANNOT BE RULED OUT SINCE THE MOISTURE
IS SOMEWHAT SHALLOW.
THE 0Z NAM AND 0Z GFS RUNS HAVE LED TO SOME INCREASED CONFIDENCE
THAT THE VA BORDER COUNTIES...ESPECIALLY FROM HARLAN NORTHEAST TO
PIKE COUNTY COULD PICK UP A HALF OF AN INCH OR SO NEAR THE
VIRGINIA BORDER LATE TONIGHT INTO EARLY ON SUNDAY. THIS AREA
APPEARS DESTINED TO BE CLIPPED BY SOME PRECIP ON THE NW EDGE OF
LOW PRESSURE PASSING TO THE SOUTHEAST OF THE AREA.
OTHERWISE...NO SIGNIFICANT CHANGES WERE MADE AT THIS TIME.
UPDATE ISSUED AT 705 PM EST SAT JAN 16 2016
UPSLOPE FLOW IS CURRENTLY PRESENT ACROSS THE AREA WITH RATHER
SHALLOW MOISTURE REMAINING UP TO NEAR 850 MB. RADAR SHOWS SOME
GENERALLY WEAK RETURNS FALLING AS EITHER VERY LIGHT SNOW OR
FLURRIES OR SOME DRIZZLE OR FREEZING DRIZZLE WHERE TEMPERATURES
ARE BELOW FREEZING. SOME LIGHT FREEZING DRIZZLE OCCURRED AT JKL
SINCE LATE AFTERNOON...BUT ONLY VERY LIGHT FLURRIES ARE FALLING AT
PRESENT. NEAR HAZARD IN PERRY COUNTY...WE RECENTLY HAD A PUBLIC
REPORT OF LIGHT SNOW WITH A DUSTING HAVING OCCURRED THERE
RECENTLY.
OVERALL...THE GRIDS HAVE BEEN ADJUSTED TO THE RECENT TRENDS IN
OBSERVATIONS AND TO ALLOW FOR FLURRIES...DRIZZLE OR FREEZING
DRIZZLE A BIT LATER INTO THE NIGHT AS MODELS HAVE THE MOISTURE
BECOMING MORE SHALLOW IN THE LOW LEVELS OVERNIGHT. CONFIDENCE IN
THE TYPE ANY LIGHT PRECIPITATION WILL TAKE IS A BIT LOW AT THIS
TIME. EITHER WAY...WITH SOME LINGERING MOISTURE ON THE PAVEMENT
IN SOME AREAS SOME BLACK ICE CANNOT BE RULED OUT OVERNIGHT. THE
HWO WAS UPDATED ACCORDINGLY AND AN SPS WAS ALSO ISSUED.
THE SECOND CONCERN IS THE POTENTIAL FOR SOME LIGHT SNOW LATE
TONIGHT AND EARLY ON SUN NEAR THE VA BORDER ON THE FAR NW FRINGE
OF A SFC LOW PASSING WELL TO THE SOUTHEAST OF THE AREA. THE 18Z
NAM AND RECENT RAP GUIDANCE KEEP THIS SOUTHEAST OF THE AREA LATE
TONIGHT OR HOLD OFF UNTIL 12Z AND AFTER AND ARE LIGHTER THAN THE
18Z GFS GUIDANCE. THE MOST RECENT HRRR RUN WOULD LEND SOME SUPPORT
FOR THE 18Z GFS GUIDANCE. WE HAVE OPTED TO INCREASE POPS TO THE
CHANCE RANGE LATE TONIGHT AND ALONG THE VA BORDER ACCORDINGLY
ALTHOUGH TRENDS WILL HAVE TO BE MONITORED FOR A POSSIBLE FURTHER
INCREASE IN POPS DURING THAT PERIOD.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 301 PM EST SAT JAN 16 2016
CURRENT CONDITIONS ACROSS THE REGION FEATURE AN AREA OF LOW LEVEL
MOISTURE OVER THE OH VALLEY REGION WITH SOME WEAK UPSLOPE
RESULTING IN A FEW AREAS OF DRIZZLE OR EVEN SNOW GRAINS. AS OF
1930Z...THE BULK OF THE LOW LEVEL MOISTURE HAS LIFTED OFF TO THE
EAST BUT SOME PATCHY DRIZZLE MAY LINGER INTO THIS EVENING. CLOUD
COVER WILL LINGER OVER THE AREA THROUGH THE OVERNIGHT PERIOD AND
INTO SUNDAY.
BY SUNDAY...A STRONG JET DIVES SOUTHEAST INTO THE GULF REGION AS A
STRONG SHORTWAVE DEVELOPS OVER THE NORTHERN GULF. THIS FEATURE
TRACK NORTHEAST ALONG THE COAST. SURFACE LOW DEVELOPMENT WRAPS
MOISTURE AROUND TO THE NORTH AND INTO THE APPALACHIAN MOUNTAINS.
FORTUNATELY...MODELS CONTINUE TO DISPLACE MOST OF THE LIFT AND
MOISTURE TO THE SOUTH AND EAST OF EASTERN KENTUCKY. THE TROUGH
DOES NUDGE NORTH ENOUGH TO BRING SOME MOISTURE INTO SOUTHEASTERN
KENTUCKY AND THUS WILL RESULT IN SOME SNOWFALL ACROSS THE AREA FOR
SUNDAY. AT THIS POINT...MODELS ARE BRINGING A FEW HUNDREDTHS INTO
THE SOUTHEAST BUT A FEW EARLIER RUNS OF THE GFS HAD UP TO THE
TENTH WHICH WOULD MEAN A BIT MORE SNOW BUT AT THIS POINT...THAT
RUN IS AN OUTLIER SO WILL GO WITH THE MORE CONSERVATIVE HI RES
SOLUTIONS. A DUSTING TO A FEW TENTHS CAN BE EXPECTED LATE TONIGHT
INTO SUNDAY.
ON THE HEALS OF THIS FEATURE WILL BE A RELATIVELY DRY ARCTIC
FRONT WITH SOME OF THE COLDEST AIR OF THE YEAR. MINUS 20 CELSIUS
850 TEMPS ARE POISED TO ENTER THE BLUEGRASS REGION SUNDAY EVENING
INTO SUNDAY NIGHT. IN FACT...AFTER 18Z SUNDAY...TEMPS WILL PLUMMET
THROUGH THE EVENING AND SUNDAY NIGHT INTO THE TEENS AND EVEN
SINGLE DIGITS IN THE BLUEGRASS COUNTIES BY MONDAY MORNING. THE
APPROACHING ARCTIC FRONT WILL BE ENOUGH TO KEEP A FEW FLURRIES
ACROSS THE AREA INTO SUNDAY NIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 PM EST SAT JAN 16 2016
...COLDEST AIR OF THE SEASON ARRIVES MONDAY...
THE MODELS ARE IN QUITE GOOD AGREEMENT ALOFT AT THE START OF THE
EXTENDED PORTION OF THE FORECAST. THEY ALL DEPICT THE DEEP TROUGH
ROLLING EAST THROUGH ONTARIO ALLOWING THE LOW HEIGHTS TO REBOUND
OVER KENTUCKY. HOWEVER...THE FLOW WILL REMAIN OUT OF THE NORTHWEST
WITH ENERGY STILL TRACKING OVER THE AREA INTO TUESDAY. THE MODELS
START TO EXHIBIT SPREAD BY MIDWEEK AS THEY DISAGREE ON THE AMOUNT OF
MINOR RIDGING THAT WILL PUSH NORTH INTO KENTUCKY FROM AN
INCREASINGLY ACTIVE SOUTHERN STREAM. FOR WEDNESDAY THE GFS IS MOST
AGGRESSIVE WITH A TROUGH IT SWINGS INTO THE MID MISSISSIPPI VALLEY
WHILE THE CANADIAN AND ECMWF ARE FLATTER WITH THIS FEATURE.
AGREEMENT IS SLIGHTLY BETTER FOR THE TRAILING RIDGE PASSING OVER THE
STATE INTO THURSDAY AHEAD OF A DEEPENING TROUGH OVER WESTERN TEXAS.
AGAIN THE GFS IS THE STRONGER MODEL WITH THIS CLOSING IT OFF AS A
LOW OVER NORTHERN ARKANSAS EARLY FRIDAY WHILE THE CANADIAN MODEL
SERVES AS A COMPROMISE SCENARIO BETWEEN THE OTHERS. HOWEVER...BY
MIDDAY FRIDAY...THE ECMWF ALSO FORMS A CLOSED LOW OVER THE DEEP
SOUTH...BUT STILL SIGNIFICANTLY WEAKER THAN THE GFS. BOTH THE GFS
AND ECMWF RUN THIS TROUGH TO THE EAST COAST BY SATURDAY MORNING...
THOUGH THE LATTER IS SUBSTANTIALLY FURTHER SOUTH AND STILL WEAKER.
THEY REMAIN PROGRESSIVE AS WELL INTO THE WEEKEND SWEEPING THE SYSTEM
OFF SHORE ON SATURDAY...AS HEIGHTS REBOUND LOCALLY. GIVEN THE
TROUBLES THE MODELS ARE HAVING FROM MID WEEK ON...WILL FAVOR A
BLENDED SOLUTION WITH A SLIGHT LEAN TOWARD A MORE DYNAMIC VERSION
MIDWAY BETWEEN THE GFS AND ECMWF TRACKS.
SENSIBLE WEATHER WILL FEATURE SOME OF THE COLDEST AIR OF THE SEASON
FLOODING SOUTHEAST INTO KENTUCKY BY MONDAY MORNING WITH A COUPLE
COLD DAYS AND NIGHTS ON TAP. DO EXPECT THE COLDEST PERIOD TO BE
MONDAY NIGHT AS THE ARCTIC HIGH SETTLES OVERHEAD RESULTING IN MOSTLY
CLEAR SKIES. THE COLD AIR WILL MODERATE INTO THE LATTER PART OF THE
WEEK JUST AS THE NEXT ILL-DEFINED SFC WEATHER SYSTEM PASSES THROUGH
WITH A CHANCE OF RAIN OR SNOW. STILL CANNOT RULE OUT A LOSS OF ICE
ON THE BACKSIDE OF THIS FIRST WEAK SYSTEM LEADING TO A CONCERN FOR
FREEZING DRIZZLE EARLY THURSDAY - WILL CONTINUE TO HIGHLIGHT THIS IN
THE HWO. THE MORE INTERESTING SYSTEM WILL TAKE SHAPE EARLY FRIDAY TO
THE SOUTH AND SHOULD BRUSH THROUGH KENTUCKY WITH A CHANCE OF SNOW OR
RAIN INTO THE WEEKEND. IF IT GETS STRONGER THAN IS CURRENTLY PROGGED
THIS COULD BE A MORE SIGNIFICANT STORM WITH THE RIGHT TRACK TO BE
IMPACTFUL. WE WILL HAVE TO WATCH THIS ONE CLOSELY AS IT EVOLVES IN
THE MODELS THROUGH THE START OF THE NEW WEEK.
ADJUSTED THE GRIDS FROM THE CR INIT MAINLY TO ACCOUNT FOR DECENT
SMALL RIDGE TO VALLEY TEMPERATURE DIFFERENCES FOR MONDAY AND TUESDAY
NIGHT. ALSO TWEAKED THE POP GRIDS LATER IN THE PERIOD TO REFLECT A
FORECAST CLOSER TO THE LATEST ECMWF.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1256 AM EST SUN JAN 17 2016
MAINLY MVFR CIGS SHOULD BE SEEN OVERNIGHT. WITH THE ONGOING
DRIZZLE AND FLURRIES...THERE HAVE BEEN A FEW INSTANCES OF CIGS
BRIEFLY DROPPING TO IFR. HOWEVER...FOR THE MOST PART...MVFR CIGS
SHOULD DOMINATE THROUGH THE REST OF THE NIGHT AND INTO SUNDAY
MORNING. CIGS SHOULD LIFT TO VFR BY EARLY AFTERNOON ON SUNDAY. AN
ARCTIC COLD FRONT WILL THEN DROP SOUTH SUNDAY AFTERNOON/EVENING
WITH NORTHWEST WINDS DEVELOPING AROUND 10 MPH WITH SOME GUSTS UP
TO 15 OR 20 MPH POSSIBLE. SOME FLURRIES OR A BRIEF SNOW SHOWER
WILL ALSO BE POSSIBLE WITH THE FRONT SUNDAY EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...SHALLENBERGER
LONG TERM...GREIF
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
125 AM EST SUN JAN 17 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 434 PM EST SAT JAN 16 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A COLD MID/UPPER LEVEL LOW
JUST NE OF WINNIPEG. AT THE SFC...WINDS WERE BACKING AHEAD OF THE
LOW WHICH HAS PUSHED THE HEAVIER LES BAND IN ERN LAKE SUPERIOR TO
THE E MUNSING. LAKE INDUCED TROUGHING EXTENDED FROM SRN INTO W CNTRL
LAKE SUPERIOR RESULTING IN THE STRONGEST LOW LEVEL CONV INTO THE
KEWEENAW NEAR HOUGHTON WHERE A VERY HEAVY LES BAND HAS PRODUCED
HIGHER SNOWFALL RATES OF A FEW INCHES PER HOUR.
TONIGHT...DEEP COLD AIR WILL CONTINUE TO SETTLE OVER THE REGION
TONIGHT WITH 850 MB TEMPS INTO THE -21C TO -25C RANGE AND 700 MB
TEMPS TO AROUND -30C. THE VERY STRONG INSTABILITY WITH LAKE INDUCED
CAPE TO 1K J/KG AND EQUILLIBRIUM HEIGHTS TO 14K FT WILL CONTINUE TO
SUPPORT THE DEVELOPMENT OF INTENSE LES BANDS. THE STRONG CONVECTION
OVER THE LAKE WILL ALSO HELP TO KEEP THE DGZ IN THE CONVECTIVE LAYER
WITH FLUFFY SNOW SLR VALUES TO AT LEAST 25/1.
AS THE MID LEVEL LOW MOVES INTO LAKE SUPERIOR...THE MODELS SUGGEST
THAT THE TROUGH TO NEAR CMX WILL GRADUALLY SINK TO THE SOUTH.
SO...ALTHOUGH HIGHER SNOWFALL RATES WILL CONTINUE...THE HEAVIER
BANDS ARE NOT EXPECTED TO REMAIN IN PLACE FOR AN EXTENDED PERIOD.
HOWEVER...ADDITIONAL SNOW AMOUNTS OF 4 TO 8 INCHES ARE EXPECTED
TONIGHT...HEAVIEST FROM CMX TO MASS CITY AND THE PORCUPINES.
OVER THE EAST...THE HEAVIEST SNOW THIS EVENING IS EXPECTED NEAR
LAKE SUPERIOR CLOSER TO PICTURED ROCKS AND GRAND MARAIS. THE HIGH
RES MODELS HAVE BEEN CONSISTENT IN SHOWING A SHARP TROUGH OR MESO LOW
DEVELOPING OVER S CNTRL LAKE SUPERIOR AND SLIDING INTO ALGER COUNTY.
STRONG LOW LEVEL CONV ASSOCIATED ON THE WRN EDGE OF THIS FEATURE WILL
BRING HEAVY LES INTO MAINLY ALGER COUNTY BTWN 06Z-12Z WITH CONTINUED
HEAVIER NNW TO NW FLOW LES BANDS SUN MORNING. THERE IS MORE
UNCERTAINTY ON HOW FAR WEST THE BAND WILL MOVE. LAND BREEZE
DEVELOPMENT SHOULD BE STRONG ENOUGH TO KEEP THE STRONGEST LES EAST OF
MARQUETTE WITH ONLY SOME LIGHTER BANDS ON THE EDGE OF THE LOW FARTHER
TO THE WEST. THE QUICK BURST OF SNOW COULD RESULT IN SNOWFALL RATES
OF 1 TO 3 INCHES PER HOUR FOR A FEW HOURS...ESPECIALY OVER WRN ALGER
COUNTY.
THE VERY COLD AIR MOVING INTO INTERIOR LOCATIONS WILL DROP WIND
CHILLS INTO THE -20 TO -30 RANGE NEAR THE WI BORDER FROM IRONWOOD TO
CRYSTAL FALLS WHERE A WIND CHILL ADVY WAS ISSUED. EXPECT ENOUGH LAKE
MODERATION FARTHER NORTH FOR WIND CHILLS MAINLY IN THE -10 TO -20
RANGE.
SUNDAY...AFTER THE BURST OF HEAVIER SNOW IN THE MORNING OVER MAINLY
WRN ALGER COUNTY...THE LES IS EXPECTED TO EVOLVE INTO LIGHT TO
MODERATE MULTIPLE WIND PARALLEL BANDS WITH A FEW HEAVIER EMBEDDED
BANDS. WHILE MORNING SNOW TOTALS COULD REACH 6 INCHES...AFTERNOON
AMOUNTS SHOULD MAINLY BE IN THE 2 TO 4 INCH RANGE.
OVER THE WEST....A SHORTER FETCH AND LESS FAVORABLE LOW LEVEL CONV
WITH THE SLOWLY BACKING NW FLOW WILL KEEP AMOUNTS IN THE 2 TO 5 INCH
RANGE. IN ADDITION...THE DGZ FALLING CLOSER TO THE LAKE SFC WILL
INHIBIT SNOW GROWTH WITH MAINLY SMALLER FLAKES THAT CAN LEAD TO LOW
VSBY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 409 PM EST SAT JAN 16 2016
MAIN ATTENTION IS ON HEALTHY LES SUN NIGHT AND MON THAT WILL
DIMINISH MON NIGHT AND TUE.
THE UPPER LOW THAT IS BRINGING THIS MASS OF COLD AIR WILL JUST E OF
THE CWA AT 00Z MON...850MB TEMPS WILL BE AROUND -23C TO START SUN
NIGHT. MODERATE TO HEAVY LES WILL BE ONGOING IN THE NW WIND
SNOWBELTS AT 00Z MON...ESPECIALLY IN AREAS E OF MARQUETTE COUNTY.
SHOULD SEE OVERALL STEADY LES SUN NIGHT INTO MUCH OF MON...WITH
DIMINISHING STARTING IN THE AFTERNOON W AND IN THE EVENING E AS THE
UPPER LOW MOVES AWAY...850MB TEMPS WARM BY 4-5 DEGREES AND WARMER
AND DRIER AIR MOVES IN ABOVE THE MOIST LAKE INFLUENCED LAYER. LAKE
INDUCED EQUILIBRIUM LEVELS SHOULD RANGE FROM 10KFT AT CMX TO 15KFT
AT GRAND MARAIS AT 00Z SUN...LOWERING BY AROUND 3KFT BY 12Z
SUN...THEN GRADUALLY DROPPING TO AROUND 6KFT OVER MOST OF THE LAKE
BY 00Z TUE. A SHORTWAVE DROPPING ACROSS LAKE SUPERIOR MON AFTERNOON
SHOULD HELP OFFSET SOME OF THE AFOREMENTIONED INCREASINGLY
UNFAVORABLE FEATURES. BETWEEN 00Z MON AND 00Z TUE...EXPECT ANOTHER 3-
5 INCHES OVER NW UPPER MI AND 6-10 INCHES OVER THE NW WIND FAVORED
AREAS OF ERN UPPER MI (MAINLY E OF MARQUETTE COUNTY). EXPECT WINDS
TO INCREASE SUN NIGHT INTO MON...WITH GUSTS UP TO 35MPH ALONG THE
SHORELINES E OF MARQUETTE AND 25-30MPH ELSEWHERE NEAR LAKE SUPERIOR.
THIS WILL PRODUCE QUITE A BIT OF BLOWING SNOW...ESPECIALLY ALONG M-
28 E OF HARVEY (NOT AS MUCH AS IF THERE WAS SIGNIFICANT ICE COVER ON
LAKE SUPERIOR AS IN YEARS PAST). MON NIGHT WILL SEE MODERATE SNOW
POTENTIAL EARLY...BUT INVERSIONS WILL BE LOWERING AND 850MB TEMPS
INCREASING TO AROUND -14C AS A SFC RIDGE MOVES TO W OF LAKE
SUPERIOR. LES WILL CONTINUE TO DIMINISH ON TUE...WITH ONLY LIGHT LES
EXPECTED...BUT WILL NOT COMPLETELY END.
SUN NIGHT AND MON MORNING WILL ALSO BE QUITE COLD WITH LOWS IN THE
SINGLE DIGITS ABOVE AND BELOW ZERO IN MOST PLACES...AROUND -10 ALONG
THE WI BORDER IN GOGEBIC COUNTY. RESULTING WIND CHILL VALUES WILL
FALL BELOW -15 OVER MUCH OF THE CENTRAL AND W...DOWN TO -25 TO -30
IN THE COLDEST SPOTS.
AFTER TUE WE COULD SEE A COUPLE SHORTWAVES MOVES THROUGH BEFORE
THU...WHICH MAY OR MAY NOT PRODUCE ANY WIDESPREAD LIGHT SNOW. THERE
IS ENOUGH UNCERTAINTY AND LACK OF SIGNIFICANT CONDITIONS AFTER TUE
TO JUST RUN WITH A CONSENSUS BLEND FOR THE FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 124 AM EST SUN JAN 17 2016
AT KIWD/KCMX...NW FLOW LAKE EFFECT CONTINUES THROUGH THE WEEKEND.
EXPECT IFR VSBY DURING THE HEAVIER SNOW BANDS AT IWD...BUT WILL STAY
MVFR FOR THE MOST PART. IFR/LIFR VSBY AT CMX WILL CONTINUE THROUGH
THIS FORECAST PERIOD AND THIS WILL BE A VARIABLE CONDITION.
AT KSAW...MVFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE FORECAST
PERIOD WITH THE LAKE EFFECT SNOW SHOWERS STAYING MOSTLY TO THE EAST.
ONLY EXCEPTION WILL BE IFR CONDITIONS THROUGH THIS MORNING WITH
LIGHT LAKE ENHANCED SNOW CONTINUING...BUT VISIBILITY IN THE SNOW
WILL BE HIGHLY VARIABLE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 434 PM EST SAT JAN 16 2016
A LOW MOVING FROM SOUTHERN ONTARIO TO QUEBEC WILL BRING COLDER AIR
ACROSS LK SUPERIOR THROUGH THE WEEKEND. BEHIND THE LOW...A TROUGH
WILL REMAIN FAIRLY STATIONARY OVER SOUTHERN LAKE SUPERIOR INTO
TUESDAY...KEEPING WIND GUSTS BETWEEN 25-30KTS. IN ADDITION...THERE
IS THE POTENTIAL FOR HEAVY FREEZING SPRAY SUNDAY INTO MONDAY. WINDS
ARE EXPECTED TO SLOWLY DIMINISH TOWARDS THE MIDDLE OF NEXT WEEK...AS
HIGH PRESSURE MOVES OVER THE UPPER GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ002-003.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ001-084.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MIZ009-010.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ007-085.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST MONDAY FOR MIZ006.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 AM THIS MORNING TO 1 PM EST
MONDAY FOR LSZ264>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1159 PM EST SAT JAN 16 2016
.AVIATION...
LOW VFR CEILINGS IN PLACE...BUT INCREASE IN SNOW SHOWER ACTIVITY
COMING OFF LAKE MICHIGAN WILL ATTEMPT TO SEND CEILINGS AND
CERTAINTY VISIBILITIES IN MVFR CATEGORY. HOWEVER...THE ARCTIC
AIRMASS OVER THE WESTERN GREAT LAKES IS EXTREMELY DRY...AND OUTSIDE
OF ANY OF THE SNOW SHOWER ACTIVITY...VFR CONDITIONS WILL PROBABLY
BE THE RULE TODAY. THE VERY COLD AIRMASS IS ALSO EXPECTED TO LIMIT
SNOW FLAKE SIZE...AND ACCUMULATIONS WILL PROBABLY REMAIN LESS THAN
AN INCH AT THE TERMINALS. GOOD SURGE OF LOW LEVEL COLD ADVECTION
AND DAYTIME MIXING SHOULD TRANSLATE TO SOLID WESTERLY GUSTS REACHING
AROUND 25 KNOTS.
FOR DTW... COULD SEE A SHORT PERIOD OF CEILING FREE SKIES AT THE
START OF THE FORECAST PERIOD...BUT VFR CLOUDS RETURN...WITH AT LEAST
FLURRIES AND PROBABLY SOME LIGHT SNOW SHOWERS SENDING VISIBILITIES
INTO MVFR TOWARD SUNDAY MORNING. ACCUMULATIONS ARE EXPECTED TO
REMAIN LIGHT...LESS THAN 1 INCH. WESTERLY WINDS WILL BE
STRONG...SUSTAINED AROUND 15 KNOTS...WITH GUSTS LIKELY REACHING 25
KNOTS OR SLIGHTLY BETTER BY SUNDAY AFTERNOON.
//DTW THRESHOLD PROBABILITIES...
* MEDIUM FOR CEILING AOB 5KFT.
* HIGH FOR SNOW AS PTYPE.
* MODERATE FOR WESTERLY WIND GUSTS EXCEEDING CROSSWIND THRESHOLDS
SUNDAY.
&&
.PREV DISCUSSION...ISSUED 800 PM EST SAT JAN 16 2016
UPDATE...
ARCTIC FRONT WAS POSITIONED FROM ABOUT THE BRIDGE TO MBL TO
CHICAGO. THIS FRONT WILL MOVE THROUGH THE FORECAST AREA AFTER
MIDNIGHT. TOOK OUT THE MENTION OF SNOW SHOWERS UNTIL THE FRONT
GETS CLOSER. AT THE TIME OF FRONTAL PASSAGE...A WEAK WAVE NOTED
OVER IA AND NRN IL...WILL INTERACT WITH THE FRONT. THE 18Z NAM
AND UPDATED RUC SUGGESTS SOME CHANCE OF MINOR QPF FOR AREAS AS FAR
NORTH AS M 46. WILL TAKE THE LATE NIGHT 50 POPS THAT WERE FOCUSED
FARTHER SOUTH AFTER 09Z...AND MOVE THEM TO 06Z TO 12Z AND EXPAND
THEM NORTH TO HIGHWAY M 46.
OTHERWISE FORECAST ON TRACK TONIGHT WITH CLOUDS AND LOW TEMPS. DID
TWEAK THE WIND UP JUST A NOTCH GIVEN THE GRADIENT AND THE COLD
AIR SPILLING INTO LOWER MICHIGAN. THAT COLD AIR APPEARS TO HAVE
SOME ABILITY TO KEEP A MIX LAYER WITH SOME DEPTH.
PREV DISCUSSION...ISSUED 405 PM EST SAT JAN 16 2016
DISCUSSION...
FORECAST FOR THE REMAINDER OF THE HOLIDAY WEEKEND WILL BE DOMINATED
BY AN ARCTIC AIR INTRUSION THAT WILL OCCUR TONIGHT AND SUNDAY AS A
LARGE UPPER LOW SLOWLY TRACKS THROUGH THE GREAT LAKES. THIS WILL
BRING VERY COLD TEMPERATURES...GUSTY WINDS/LOW WIND CHILLS...AND
CHANCES FOR SNOW SHOWERS.
AREA OF ENHANCED LAKE EFFECT...MAINLY IN ONE BAND...WITH CONNECTIONS
TO BOTH LAKE SUPERIOR AND LAKE MICHIGAN THAT AFFECTED PRIMARILY THE
SAGINAW VALLEY EARLY TODAY SHIFTED AS WINDS TURNED MORE WESTERLY.
LIGHT SHOWERS AND FLURRIES HAVE SINCE BEEN MAKING THEIR WAY INTO THE
EASTERN PART OF THE STATE THIS AFTERNOON...WITH LATEST
RADAR/SATELLITE INDICATING MOISTURE IS RELEASING OFF LAKE MICHIGAN.
WHAT IS LEFT OF THE SHOWERS/CLOUDS OVER THE WESTERN PART OF THE
STATE SHOULD MAKE THEIR WAY ACROSS SOUTHEAST MICHIGAN BETWEEN 4PM
AND 8PM. MAY THEN SEE SOME BREAKS OR CLEAR PATCHES IN CLOUDS AS
DRIER AIR EVIDENT ON SATELLITE OVER LAKE MICHIGAN AND EXTENDING BACK
THROUGH WISCONSIN WORKS THROUGH. DRIER AIR IS AT THE LEAD EDGE OF
ARCTIC AIRMASS THAT WILL SPILL INTO THE AREA FOR THE REMAINDER OF
THE WEEKEND. PRECIPITATION IS CURRENTLY NOT OCCURRING UPSTREAM IN
ASSOCIATION WITH THE FRONTAL PASSAGE. GIVEN THIS AIRMASS WILL BE
MOVING OVER A RELATIVELY WARM LAKE MICHIGAN...42 DEGREES PER LATEST
SATELLITE ANALYSIS...AND TEMPS ARE IN THE SINGLE DIGITS BEHIND THE
FRONT...WILL KEEP SOME LOW POPS IN THE FORECAST TO COVER ANY LAKE
EFFECT THAT STREAMS THIS FAR EAST.
UPTICK IN SNOW SHOWER ACTIVITY IS EXPECTED VERY LATE TONIGHT THROUGH
SUNDAY AFTERNOON AS DEEPER MOISTURE ARRIVES...COLD AIR ADVECTION
INCREASES LAKE RESPONSE...AND PVA ASSOCIATED WITH THE UPPER LOW
WORKS ACROSS. COOLING THERMAL FIELDS WILL ALSO ALLOW MOISTURE TO
BECOME BETTER PLACED WITHIN THE DENDRITIC GROWTH ZONE. WEST TO WEST-
NORTHWEST WINDS WILL FAVOR THE SOUTHERN PORTION OF THE FORECAST AREA
FOR LAKE ENHANCED SNOW SHOWERS LATE TONIGHT AND SUNDAY. WITH
PRECIPITATION OCCURRING IN BANDS...ACCUMULATIONS WILL BE HIGHLY
VARIABLE (MAYBE UP TO AN INCH)...AND RAPID FLUCTUATIONS IN VISIBILITY
ARE POSSIBLE UNTIL LATE AFTERNOON WHEN DRIER AIR SHOULD AGAIN WORK
INTO THE SOUTHERN CENTRAL PORTIONS OF THE FORECAST AREA. SURFACE
TROUGH WILL DEEPEN OVER LAKE HURON TONIGHT AND SUNDAY AS THE UPPER
LOW APPROACHES...EVENTUALLY RESULTING IN A COLD FRONT DROPPING SOUTH
INTO THE SOUTH-CENTRAL LOWER MICHIGAN LATE SUNDAY...AND INTO THE
REST OF THE AREA SUNDAY NIGHT. THIS WILL AGAIN BRING CHANCES FOR
SNOW SHOWERS.
MAIN STORY WILL REALLY BE THE ARRIVAL OF MUCH COLDER TEMPERATURES.
THE COLD AIR WILL ALSO COMBINE WITH GUSTY WINDS THROUGH MUCH OF THE
WEEKEND TO PRODUCE SOME OF THE COLDEST WIND CHILLS SO FAR THIS
WINTER. TEMPS FALLING INTO THE TEENS TONIGHT WILL RECOVER LITTLE ON
SUNDAY AS ARCTIC AIRMASS CONTINUES TO SPILL IN. GUSTY WINDS WILL
KEEP WIND CHILLS BELOW ZERO FOR MUCH OF THE AREA BOTH TOMORROW AND
MONDAY (LOW SINGLE DIGITS FOR DETROIT). SINGLE DIGIT LOWS ARE THEN
EXPECTED BOTH SUNDAY AND MONDAY NIGHTS...PRODUCING WIND CHILLS IN
THE -10 TO -15F DEGREE RANGE SUNDAY NIGHT.
TUESDAY THROUGH SUNDAY.
A COUPLE OF WEAK WEATHER SYSTEMS ARE EXPECTED TO MOVE ACROSS
SOUTHEAST MICHIGAN BEGINNING MIDWEEK. THESE SYSTEMS WILL BRING IN
CHANCES FOR FLURRIES AND LIGHT SNOW SHOWERS THROUGH FRIDAY EVENING.
LITTLE TO NO ACCUMULATION IS CURRENTLY ANTICIPATED WITH THESE
SHOWERS. TEMPERATURES WILL GRADUALLY WARM BACK TOWARD THE SEASONAL
NORM BY THE END OF THE FORECAST PERIOD.
MARINE...
AN ARCTIC COLD FRONT WILL MOVE THROUGH THE SOUTHERN GREAT LAKES
TONIGHT AND LEAVE A LOW/SURFACE TROUGH STALLED OVER LAKE SUPERIOR
AND NORTHERN LAKE HURON. THIS WILL KEEP THE STRONGEST WIND FOCUSED
FROM THE SOUTH HALF OF LAKE HURON THROUGH WESTERN LAKE ERIE SUNDAY
AND MONDAY. THE WESTERLY FLOW OVER THE SHORT FETCH OF SOUTHERN LAKE
HURON OPEN WATER FAVORS GUSTS MOSTLY BELOW GALES AND GUSTS AROUND 25
KNOTS OR LESS OVER LAKE ST CLAIR AND THE MICHIGAN WATERS OF LAKE
ERIE. WHILE HEADLINES FOR WIND ARE NOT YET NEEDED...THE ARCTIC AIR
SPILLING OVER THE REGION WILL MAKE FREEZING SPRAY AND ICING A
CONCERN IN THE FORECAST. THE BEST COMBINATION OF WIND...WATER
TEMPERATURE...AND AIR TEMPERATURE ARE ONLY SUPPORTING MODERATE
FREEZING SPRAY IN WESTERLY FLOW OVER U.S. WATERS OVER THE SOUTH HALF
OF LAKE HURON. THIS WILL BE MONITORED ALSO WITHOUT A HEADLINE FOR
NOW.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....SF
UPDATE.......RBP
DISCUSSION...HLO/DE
MARINE.......BT
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1147 PM EST SAT JAN 16 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 434 PM EST SAT JAN 16 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A COLD MID/UPPER LEVEL LOW
JUST NE OF WINNIPEG. AT THE SFC...WINDS WERE BACKING AHEAD OF THE
LOW WHICH HAS PUSHED THE HEAVIER LES BAND IN ERN LAKE SUPERIOR TO
THE E MUNSING. LAKE INDUCED TROUGHING EXTENDED FROM SRN INTO W CNTRL
LAKE SUPERIOR RESULTING IN THE STRONGEST LOW LEVEL CONV INTO THE
KEWEENAW NEAR HOUGHTON WHERE A VERY HEAVY LES BAND HAS PRODUCED
HIGHER SNOWFALL RATES OF A FEW INCHES PER HOUR.
TONIGHT...DEEP COLD AIR WILL CONTINUE TO SETTLE OVER THE REGION
TONIGHT WITH 850 MB TEMPS INTO THE -21C TO -25C RANGE AND 700 MB
TEMPS TO AROUND -30C. THE VERY STRONG INSTABILITY WITH LAKE INDUCED
CAPE TO 1K J/KG AND EQUILLIBRIUM HEIGHTS TO 14K FT WILL CONTINUE TO
SUPPORT THE DEVELOPMENT OF INTENSE LES BANDS. THE STRONG CONVECTION
OVER THE LAKE WILL ALSO HELP TO KEEP THE DGZ IN THE CONVECTIVE LAYER
WITH FLUFFY SNOW SLR VALUES TO AT LEAST 25/1.
AS THE MID LEVEL LOW MOVES INTO LAKE SUPERIOR...THE MODELS SUGGEST
THAT THE TROUGH TO NEAR CMX WILL GRADUALLY SINK TO THE SOUTH.
SO...ALTHOUGH HIGHER SNOWFALL RATES WILL CONTINUE...THE HEAVIER
BANDS ARE NOT EXPECTED TO REMAIN IN PLACE FOR AN EXTENDED PERIOD.
HOWEVER...ADDITIONAL SNOW AMOUNTS OF 4 TO 8 INCHES ARE EXPECTED
TONIGHT...HEAVIEST FROM CMX TO MASS CITY AND THE PORCUPINES.
OVER THE EAST...THE HEAVIEST SNOW THIS EVENING IS EXPECTED NEAR
LAKE SUPERIOR CLOSER TO PICTURED ROCKS AND GRAND MARAIS. THE HIGH
RES MODELS HAVE BEEN CONSISTENT IN SHOWING A SHARP TROUGH OR MESO LOW
DEVELOPING OVER S CNTRL LAKE SUPERIOR AND SLIDING INTO ALGER COUNTY.
STRONG LOW LEVEL CONV ASSOCIATED ON THE WRN EDGE OF THIS FEATURE WILL
BRING HEAVY LES INTO MAINLY ALGER COUNTY BTWN 06Z-12Z WITH CONTINUED
HEAVIER NNW TO NW FLOW LES BANDS SUN MORNING. THERE IS MORE
UNCERTAINTY ON HOW FAR WEST THE BAND WILL MOVE. LAND BREEZE
DEVELOPMENT SHOULD BE STRONG ENOUGH TO KEEP THE STRONGEST LES EAST OF
MARQUETTE WITH ONLY SOME LIGHTER BANDS ON THE EDGE OF THE LOW FARTHER
TO THE WEST. THE QUICK BURST OF SNOW COULD RESULT IN SNOWFALL RATES
OF 1 TO 3 INCHES PER HOUR FOR A FEW HOURS...ESPECIALY OVER WRN ALGER
COUNTY.
THE VERY COLD AIR MOVING INTO INTERIOR LOCATIONS WILL DROP WIND
CHILLS INTO THE -20 TO -30 RANGE NEAR THE WI BORDER FROM IRONWOOD TO
CRYSTAL FALLS WHERE A WIND CHILL ADVY WAS ISSUED. EXPECT ENOUGH LAKE
MODERATION FARTHER NORTH FOR WIND CHILLS MAINLY IN THE -10 TO -20
RANGE.
SUNDAY...AFTER THE BURST OF HEAVIER SNOW IN THE MORNING OVER MAINLY
WRN ALGER COUNTY...THE LES IS EXPECTED TO EVOLVE INTO LIGHT TO
MODERATE MULTIPLE WIND PARALLEL BANDS WITH A FEW HEAVIER EMBEDDED
BANDS. WHILE MORNING SNOW TOTALS COULD REACH 6 INCHES...AFTERNOON
AMOUNTS SHOULD MAINLY BE IN THE 2 TO 4 INCH RANGE.
OVER THE WEST....A SHORTER FETCH AND LESS FAVORABLE LOW LEVEL CONV
WITH THE SLOWLY BACKING NW FLOW WILL KEEP AMOUNTS IN THE 2 TO 5 INCH
RANGE. IN ADDITION...THE DGZ FALLING CLOSER TO THE LAKE SFC WILL
INHIBIT SNOW GROWTH WITH MAINLY SMALLER FLAKES THAT CAN LEAD TO LOW
VSBY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 409 PM EST SAT JAN 16 2016
MAIN ATTENTION IS ON HEALTHY LES SUN NIGHT AND MON THAT WILL
DIMINISH MON NIGHT AND TUE.
THE UPPER LOW THAT IS BRINGING THIS MASS OF COLD AIR WILL JUST E OF
THE CWA AT 00Z MON...850MB TEMPS WILL BE AROUND -23C TO START SUN
NIGHT. MODERATE TO HEAVY LES WILL BE ONGOING IN THE NW WIND
SNOWBELTS AT 00Z MON...ESPECIALLY IN AREAS E OF MARQUETTE COUNTY.
SHOULD SEE OVERALL STEADY LES SUN NIGHT INTO MUCH OF MON...WITH
DIMINISHING STARTING IN THE AFTERNOON W AND IN THE EVENING E AS THE
UPPER LOW MOVES AWAY...850MB TEMPS WARM BY 4-5 DEGREES AND WARMER
AND DRIER AIR MOVES IN ABOVE THE MOIST LAKE INFLUENCED LAYER. LAKE
INDUCED EQUILIBRIUM LEVELS SHOULD RANGE FROM 10KFT AT CMX TO 15KFT
AT GRAND MARAIS AT 00Z SUN...LOWERING BY AROUND 3KFT BY 12Z
SUN...THEN GRADUALLY DROPPING TO AROUND 6KFT OVER MOST OF THE LAKE
BY 00Z TUE. A SHORTWAVE DROPPING ACROSS LAKE SUPERIOR MON AFTERNOON
SHOULD HELP OFFSET SOME OF THE AFOREMENTIONED INCREASINGLY
UNFAVORABLE FEATURES. BETWEEN 00Z MON AND 00Z TUE...EXPECT ANOTHER 3-
5 INCHES OVER NW UPPER MI AND 6-10 INCHES OVER THE NW WIND FAVORED
AREAS OF ERN UPPER MI (MAINLY E OF MARQUETTE COUNTY). EXPECT WINDS
TO INCREASE SUN NIGHT INTO MON...WITH GUSTS UP TO 35MPH ALONG THE
SHORELINES E OF MARQUETTE AND 25-30MPH ELSEWHERE NEAR LAKE SUPERIOR.
THIS WILL PRODUCE QUITE A BIT OF BLOWING SNOW...ESPECIALLY ALONG M-
28 E OF HARVEY (NOT AS MUCH AS IF THERE WAS SIGNIFICANT ICE COVER ON
LAKE SUPERIOR AS IN YEARS PAST). MON NIGHT WILL SEE MODERATE SNOW
POTENTIAL EARLY...BUT INVERSIONS WILL BE LOWERING AND 850MB TEMPS
INCREASING TO AROUND -14C AS A SFC RIDGE MOVES TO W OF LAKE
SUPERIOR. LES WILL CONTINUE TO DIMINISH ON TUE...WITH ONLY LIGHT LES
EXPECTED...BUT WILL NOT COMPLETELY END.
SUN NIGHT AND MON MORNING WILL ALSO BE QUITE COLD WITH LOWS IN THE
SINGLE DIGITS ABOVE AND BELOW ZERO IN MOST PLACES...AROUND -10 ALONG
THE WI BORDER IN GOGEBIC COUNTY. RESULTING WIND CHILL VALUES WILL
FALL BELOW -15 OVER MUCH OF THE CENTRAL AND W...DOWN TO -25 TO -30
IN THE COLDEST SPOTS.
AFTER TUE WE COULD SEE A COUPLE SHORTWAVES MOVES THROUGH BEFORE
THU...WHICH MAY OR MAY NOT PRODUCE ANY WIDESPREAD LIGHT SNOW. THERE
IS ENOUGH UNCERTAINTY AND LACK OF SIGNIFICANT CONDITIONS AFTER TUE
TO JUST RUN WITH A CONSENSUS BLEND FOR THE FORECAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1147 PM EST SAT JAN 16 2016
AT KIWD/KCMX...NW FLOW LAKE EFFECT CONTINUES THROUGH THE WEEKEND.
EXPECT IFR VSBY DURING THE HEAVIER SNOW BANDS AT IWD...BUT WILL STAY
MVFR FOR THE MOST PART. IFR/LIFR VSBY AT CMX WILL CONTINUE THROUGH
THIS FORECAST PERIOD AND THIS WILL BE A VARIABLE CONDITION.
AT KSAW...MVFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE FORECAST
PERIOD WITH THE LAKE EFFECT SNOW SHOWERS STAYING MOSTLY TO THE EAST.
ONLY EXCEPTION WILL BE IFR CONDITIONS THROUGH THIS MORNING WITH
LIGHT LAKE ENHANCED SNOW CONTINUING...BUT VISIBILITY IN THE SNOW
WILL BE HIGHLY VARIABLE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 434 PM EST SAT JAN 16 2016
A LOW MOVING FROM SOUTHERN ONTARIO TO QUEBEC WILL BRING COLDER AIR
ACROSS LK SUPERIOR THROUGH THE WEEKEND. BEHIND THE LOW...A TROUGH
WILL REMAIN FAIRLY STATIONARY OVER SOUTHERN LAKE SUPERIOR INTO
TUESDAY...KEEPING WIND GUSTS BETWEEN 25-30KTS. IN ADDITION...THERE
IS THE POTENTIAL FOR HEAVY FREEZING SPRAY SUNDAY INTO MONDAY. WINDS
ARE EXPECTED TO SLOWLY DIMINISH TOWARDS THE MIDDLE OF NEXT WEEK...AS
HIGH PRESSURE MOVES OVER THE UPPER GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST SUNDAY FOR MIZ002-003.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST SUNDAY FOR MIZ001-084.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MIZ009-010.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ007-085.
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST MONDAY FOR MIZ006.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING FROM 7 AM SUNDAY TO 1 PM EST MONDAY
FOR LSZ264>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS PORTLAND OR
901 PM PST SAT JAN 16 2016
.SYNOPSIS...A BRIEF BREAK IN RAIN TONIGHT THEN A FRONT WILL BRING
ANOTHER ROUND OF RAIN AND HIGH ELEVATION SNOW SUNDAY AND SUNDAY
NIGHT. THERE WILL BE ANOTHER BREAK IN RAIN MONDAY MORNING BEFORE A
COUPLE OF LOWS PRODUCE ADDITIONAL RAIN AND CASCADE SNOW MONDAY
AFTERNOON THROUGH TUESDAY NIGHT. THE PROGRESSIVE WEATHER PATTERN OF
RAIN EVERY 24 HOURS OR SO WILL PERSIST THROUGH NEXT WEEKEND.
&&
.SHORT TERM...RAIN HAS GENERALLY MOVED OUT OF THE AREA THIS EVENING
WITH THE EXCEPTION OF A FEW DISSIPATING SHOWERS IN THE SOUTH WASHINGTON
CASCADES. RADAR SHOWS A BAND OF REFLECTIVITY MOVING NORTHEAST ACROSS
THE AREA BUT NO REPORTS OF RAIN ON THE GROUND SO IT IS LIKELY VIRGA.
THE 03Z HRRR AND RAP SHOW2 WHAT LOOKS SOME WARM FRONTAL PRECIP OVER
THE COAST AND COAST RANGE MUCH EARLIER THAN THE REST OF THE
MODELS...BEGINNING AS EARLY AS 11 PM. THEN LONGER LASTING AND
STEADIER PRECIP ARRIVES ON THE COAST BETWEEN ABOUT 4 AM AND 6
AM...MOVING INLAND THROUGH THE MORNING HOURS. WITH NOTHING SHOWING UP
ON IR SATELLITE IMAGERY AT THE MOMENT TO INDICATE RAIN HEADED INTO
THE AREA BEFORE MIDNIGHT...IT IS HARD TO BELIEVE THE HRRR AND RAP
SOLUTION BUT IT SHOULD BE MORE THAN A COINCIDENCE THAT THEY ARE BOTH
SHOWING SIMILAR SCENARIOS. WILL BE INTERESTING TO SEE IF THE 06Z RUN
OF THE NAM AND GFS SHOWS THE PRELIMINARY PRECIP BUT BY THE TIME THEY
COME IN THE PRECIP WILL HAVE EITHER DEVELOPED OR NOT. OVERALL...MOST
AREAS WILL REMAIN DRY FOR MUCH OF THE NIGHT UNTIL THE WIDESPREAD
STEADY RAIN ARRIVES SUNDAY MORNING....FIRST AT THE COAST LIKELY
BEFORE SUNRISE AND THEN SPREADING INLAND THROUGH THE MORNING COMMUTE.
MODEST MOISTURE IS AVAILABLE WITH THIS SYSTEM WITH FORECASTED
TROPICAL PRECIPITABLE WATER VALUES NEAR AN INCH. THIS MOISTURE
COMBINED WITH DECENT LIFT FROM A 120+ KT UPPER JET PROVIDES THE
POTENTIAL FOR DECENT RAINFALL TOTALS. HOWEVER...THE FRONT IS RATHER
QUICK MOVING...WHICH SHOULD HELP LIMIT THE TOTALS AND DETER ANY
HYDROLOGICAL PROBLEMS. OVERALL EXPECT 0.75 TO 1.25 INCHES OF RAIN
OVER THE COAST...COAST RANGE AND CASCADES SUNDAY MORNING THROUGH
SUNDAY AFTERNOON WITH BETWEEN 0.4 AND 0.65 INCH FOR THE INTERIOR
VALLEYS.
A SHORTWAVE UPPER LEVEL TROUGH WILL MOVE OVER THE REGION SUNDAY
EVENING AND BRING THE POTENTIAL FOR THUNDERSTORMS ALONG THE COASTAL
WATERS AND THE IMMEDIATE COAST. THE UPPER TROUGH WILL ALSO BRING
COOLER AIR AND SNOW LEVELS WILL LOWER TO AROUND 4500 FEET SUNDAY
NIGHT. CAN EXPECT AN ADDITIONAL 0.25 TO 0.5 INCH FOR THE CASCADES
SUNDAY EVENING AND SUNDAY NIGHT WITH LESS THAN 0.25 INCH ELSEWHERE.
A FEW SHOWERS WILL LINGER OVER THE HIGHER TERRAIN EARLY MONDAY
MORNING...MAINLY TO THE NORTH. THE REST OF THE MORNING SHOULD BE
FAIRLY DRY BEFORE ANOTHER OCCLUDED FRONT BRINGS ADDITIONAL RAIN
MONDAY AFTERNOON. THIS FRONT WILL MOVE ACROSS THE REGION MONDAY
AFTERNOON AND MONDAY NIGHT. ANOTHER LOW WILL APPROACH FROM THE SW
MONDAY NIGHT...AND BRING ANOTHER FRONTAL SYSTEM TUESDAY AND TUESDAY
NIGHT. THERE MAY NOT BE MUCH OF A BREAK BETWEEN THE TWO FRONTS...AND
CAN GENERALLY EXPECT ANOTHER 0.75 TO 1.25 INCHES OF RAIN FOR THE
COAST RANGE AND CASCADES...WITH 0.4 TO 0.6 INCH FOR THE INTERIOR
VALLEYS MONDAY MORNING THROUGH TUESDAY NIGHT. SNOW LEVELS WILL BE
AROUND 4000 FEET. BOWEN/TJ
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...TUESDAY NIGHT
THROUGH SATURDAY...ACTIVE AND MILD WEATHER PATTERN THROUGH NEXT
WEEKEND. TUESDAY NIGHT WE WILL HAVE A FAST MOVING LOW PRESSURE SYSTEM
MOVING OFF TO THE EAST. THE ECMWF IS A LITTLE SLOWER...KEEPING MORE
RAIN OVER THE AREA LATER...WHILE THE
GFS MOSTLY DRIES OUT EVERYWHERE WEST OF THE CASCADES WEDNESDAY
MORNING. WEDNESDAY MIDDAY THROUGH THE EARLY EVENING HOURS SHOULD BE
MOSTLY DRY AS SHORTWAVE RIDGING BUILDS OVER THE AREA AHEAD OF THE
NEXT SYSTEM BRINGING MORE RAIN WEDNESDAY NIGHT THROUGH THURSDAY.
MODELS HAVE THIS NEXT SYSTEM BRINGING TROPICAL MOISTURE FURTHER
NORTH...LOOKING LIKE A POSSIBLE ATMOSPHERIC RIVER EVENT. THIS MEANS
GREATER POTENTIAL FOR HEAVY RAIN ACROSS OUR AREA. DON`T FEEL
CONFIDENT ABOUT THE LOCATION OF THE HEAVIEST RAIN THIS FAR OUT...BUT
WITH THE MORE SOUTHERN STORM TRACK IN PLACE WOULD THINK A GREATER
POTENTIAL FOR HEAVY RAIN OVER THE SOUTHERN HALF OF OUR AREA. THIS
TYPE OF EVENT WILL BRING TEMPERATURES UP ABOVE NORMAL...AND LIFT
SNOW LEVELS UP ABOVE THE PASSES ON THURSDAY INTO EARLY FRIDAY DURING
THE BULK OF THE PRECIPITATION. WEATHER LOOKS TO REMAIN ACTIVE INTO
THE WEEKEND WITH SNOW LEVELS DROPPING BACK DOWN BELOW THE PASSES
FRIDAY NIGHT...THOUGH DETAILS ARE VERY UNCERTAIN THAT FAR OUT IN THE
FORECAST PERIOD IN THIS TYPE OF PATTERN. -MCCOY
&&
.AVIATION...PRIMARILY VFR THIS EVENING...EXCEPT FOR POCKETS OF
MVFR CIGS ALONG THE COAST AND MOUNTAIN OBSCURATION. EXPECT
VFR TO PREVAIL ALONG THE COAST THROUGH ABOUT 10Z THEN CONDITIONS
FALL TO MVFR OR LOWER BETWEEN 10Z AND 16Z SUN. IMPROVEMENT TO VFR
LATE SUN AFTERNOON INTO THE EVENING. INLAND AREAS SHOULD HOLD ON
TO VFR THROUGH AT LEAST 12Z AND THEN DROP INTO MVFR DURING THE
MORNING. MOUNTAINS BECOME OBSCURED SUN MORNING. OFFSHORE LOW-LEVEL
GRADIENT DEVELOPS THROUGH THE COLUMBIA GORGE TONIGHT AND PERSISTS
INTO THE EARLY AFTERNOON. LLWS POSSIBLE WITH SURFACE EAST WIND AND
S-SW 30-40KT WIND AT FL020.
KPDX AND APPROACHES...GENERALLY VFR THROUGH AT LEAST 12Z SUN.
CONDITIONS LOWER IN THE MORNING WITH RAIN DEVELOPING AROUND
SUNRISE. IMPROVEMENT TO VFR LATE SUN AFTERNOON. E-SE SURFACE WIND
THROUGH EARLY AFTERNOON THEN A SWITCH TO THE S. POTENTIAL LLWS
ALONG ERN APPROACHES TONIGHT THROUGH EARLY SUN AFTERNOON. WEISHAAR
&&
.MARINE...MINIMAL CHANGES TO THE SHORT TERM FORECAST. STILL
LOOKING AT GALES FOR THE WATERS TONIGHT THROUGH SUN MORNING. PEAK
WIND PERIOD FOR THE OUTER WATERS SHOULD BE 08Z-13Z AND 10Z-14Z OR
SO FOR THE INNER WATERS. LATEST NAM RUN SEEMS TO BE A LITTLE
LIGHTER ON WIND SPEEDS COMPARED TO THE PREVIOUS VERSION. NEWEST
NAM HAS 30-35 KT BOUNDARY LAYER WIND SPEEDS FOR THE OUTER WATERS
12Z SUN WITH 975 MB SPEEDS IN THE 35-42 KT RANGE. FAR SW WATERS
MAY SEE A FEW GUSTS UP TO 45 KT. WIND SPEEDS EASE LATE SUN MORNING
THROUGH THE AFTERNOON. THE NEXT FRONTAL SYSTEM MOVES THROUGH THE
WATERS MON. LATEST NAM AND GFS SHOW POSSIBLE LOW-END GALE FORCE
GUSTS DEVELOPING LATE MON MORNING AND CONTINUING THROUGH THE
AFTERNOON.
MAJOR MODEL DIFFERENCES REGARDING THE TUE SYSTEM. THE LATEST NAM
HAS A 988 MB LOW NEAR 46N 125W 00Z WED WHILE THE GFS HAS IT INLAND
OVER THE COLUMBIA BASIN. IF THE NAM VERIFIES...STORM FORCE WIND
NOT OUT OF THE QUESTION. THEN THERE IS THE 12Z ECMWF MODEL WHICH A
990 MB LOW A LITTLE WEST OF BUOY 46027.
SEAS HOVERING AROUND 20 FT THIS EVENING...PRETTY CLOSE TO THE 12
HR ENP GUIDANCE. LONG-PERIOD 19-20 SEC SWELL RESULTING IN A LOT
ENERGY WITH THESE WAVES. WAVE HEIGHTS EASE JUST A BIT LATE TONIGHT
THROUGH SUN MORNING THEN RAMP UP WITH THE NEXT SYSTEM...LIKELY
PEAKING AT 20 TO 22 FT EARLY SUN EVENING. SEAS REMAIN ELEVATED IN
THE MID TEENS THROUGH LATE MONDAY. WEISHAAR
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH SURF ADVISORY UNTIL MIDNIGHT PST SUNDAY NIGHT FOR CENTRAL
OREGON COAST-NORTH OREGON COAST.
WA...HIGH SURF ADVISORY UNTIL MIDNIGHT PST SUNDAY NIGHT FOR SOUTH
WASHINGTON COAST.
PZ...GALE WARNING UNTIL 9 AM PST SUNDAY 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 ROUGH COLUMBIA RIVER BAR UNTIL 10 PM
PST SUNDAY.
GALE WARNING FROM 3 AM TO 9 AM PST SUNDAY FOR COASTAL WATERS
FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 10 NM-
COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OR OUT 10 NM.
&&
$$
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 FORT WORTH TX
301 AM CST SUN JAN 17 2016
.DISCUSSION...
COLD MORNING IN PROGRESS ACROSS NORTH TEXAS AS A SURFACE HIGH
PRESSURE CENTER MOVES ACROSS THE REGION. WINDS HAVE GONE CALM IN
MANY LOCATIONS AND SURFACE MOISTURE LINGERS. THIS HAS RESULTED IN
AREAS OF SHALLOW FOG IN SOME LOCATIONS. IN OTHERS...WHERE T/TD
SPREADS ARE A LITTLE HIGHER...THICK FROST HAS DEVELOPED. THE FOG
SHOULD BE PATCHY AND SHALLOW AT BEST AND DOES NOT REALLY APPEAR
THAT IT WILL DEPOSIT ICE ON ANY AREA ROADS. AFTER A COLD START...
TEMPERATURES SHOULD REBOUND NICELY INTO THE LOW TO MID 50S BY THIS
AFTERNOON.
THE WARMUP WILL BE BRIEF AS ANOTHER COLD FRONT IS EXPECTED TO MOVE
THROUGH NORTH TEXAS TONIGHT INTO MONDAY MORNING. A LARGE UPPER LOW
WILL BE MOVING THROUGH THE GREAT LAKES REGION DURING THIS TIME AND
WILL ALLOW A 1030MB SURFACE HIGH TO BUILD SOUTHWARD THROUGH THE
PLAINS. TEMPERATURES ARE VERY COLD ACROSS THE UPPER PLAINS WITH
READINGS IN THE -10 TO -20F RANGE ACROSS PARTS OF THE DAKOTAS AND
MINNESOTA. WHILE THE BRUNT OF THE COLDEST AIR WILL STAY WELL TO
OUR NORTHEAST...THE PATTERN IS FAVORABLE TO ALLOW SHALLOW VERY
COLD AIR TO SPILL SOUTHWARD THROUGH THE PLAINS TODAY. AS IS
TYPICAL WITH VERY SHALLOW COLD AIR...THE MODELS ARE USUALLY TOO
WARM WITH TEMPERATURES DUE TO THEIR LACK OF LOW LEVEL RESOLUTION.
THE LATEST HIGH RESOLUTION RAP GUIDANCE DOES GIVE A SMALL HINT
THAT THE AIR MAY BE COLDER ON MONDAY ACROSS NORTH TEXAS THAN
CURRENTLY INDICATED BY THE GFS/NAM/ECMWF. THE LATEST RUN HAS
TEMPERATURES ACROSS PARTS OF CENTRAL OKLAHOMA IN THE LOW 20S ON
SUNDAY EVENING. THIS IS ABOUT 10 DEGREES COLDER THAN THE CURRENT
MOS GUIDANCE. WITH THAT IN MIND...WILL UNDERCUT THE MOS HIGHS FOR
MONDAY...PARTICULARLY NORTH OF I-20. WHILE COLD AIR WILL SPILL
INTO NORTH TEXAS...THE TRAJECTORY OF THE SURFACE HIGH AND THE
PROGRESSIVE NATURE OF THE UPPER PATTERN WILL ENSURE THAT IT WILL
BE SHORT LIVED ACROSS THE REGION. MOSTLY SUNNY SKIES AND A RETURN
TO SOUTHERLY FLOW LATE IN THE DAY ON MONDAY WILL LIKELY MIX SOME
OF THE COLDER AIR BEFORE THE SUN SETS. TEMPERATURES ARE LIKELY TO
BE IN THE LOW/MID 40S ACROSS THE NORTHERN HALF OF THE CWA WITH
UPPER 40S AND LOWER 50S SOUTH OF I-20.
THERE WILL BE SEVERAL SHORTWAVE TROUGHS THAT MOVE THROUGH THE
PLAINS THROUGH NEXT WEEK AND TIMING EACH ONE IS PROVING TO BE
RATHER DIFFICULT. THERE IS STILL QUITE A BIT OF SPREAD IN MODEL
GUIDANCE THROUGH THE END OF THE WEEK. IT DOES APPEAR THAT LOW
LEVEL FLOW WILL BECOME MORE SOUTH/SOUTHWEST ON TUESDAY WHICH WILL
ALLOW FOR A QUICK WARMUP IN TEMPERATURES BACK INTO THE 60S. A WEAK
COLD FRONT WILL MOVE THROUGH ON WEDNESDAY WITH ANOTHER COOL DOWN
BACK TOWARD SEASONAL NORMS. THERE IS A SMALL CHANCE FOR SHOWERS
ALONG THIS FRONT...MAINLY IN OUR SOUTH/SOUTHEAST COUNTIES ALTHOUGH
MOISTURE IS SOMEWHAT LIMITED. SLIGHTLY BETTER RAIN CHANCES APPEAR
TO ARRIVE LATE WEDNESDAY INTO EARLY THURSDAY AS A STRONG SHORTWAVE
MOVES THROUGH THE SOUTHERN PLAINS. THIS RESULTS IN ANOTHER SURFACE
LOW TRACKING ACROSS NORTH TEXAS WITH SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS EXPECTED TO DEVELOP ON THE EAST SIDE OF THE
LOW. A QUICK LOOK AT THE 00Z ENSEMBLE GUIDANCE INDICATES THIS
SHORTWAVE AND ASSOCIATED SURFACE FEATURES IN MOST OF THE ENSEMBLE
MEMBERS...HOWEVER THE TRACK IS QUITE VARIED WITH ABOUT HALF OF
THE GUIDANCE INDICATING RAIN/STORMS ACROSS OUR AREA...AND THE
OTHER HALF FARTHER EAST INTO THE ARKLATEX. THIS RESULTS IN A LOWER
OVERALL CONFIDENCE IN RAIN MIDWEEK BUT WE WILL MAINTAIN 20/30 POPS
LATE WEDNESDAY INTO THURSDAY WITH BEST CHANCES EAST OF INTERSTATE
35.
TEMPERATURES WILL GENERALLY REMAIN WITHIN 5 DEGREES OR SO OF
SEASONAL NORMS THROUGH THE WEEK.
DUNN
&&
.AVIATION...
/ISSUED 1123 PM CST SAT JAN 16 2016/
VFR SHOULD PREVAIL THROUGH THE PERIOD. GENERALLY CLEAR SKIES NOW
WILL GIVE WAY TO INCREASING HIGH CLOUDS SUNDAY MORNING. VERY LIGHT
WEST WINDS ARE EXPECTED TONIGHT...BUT THESE WILL BACK AROUND TO
THE SOUTHWEST BY SUNRISE AND TO THE SOUTH BY MID MORNING. SOUTH
WINDS AT 5 TO 10KT WILL PREVAIL SUNDAY AFTERNOON BUT WILL CONTINUE
TO BACK AROUND TO THE EAST AFTER SUNSET AND NORTHEAST IN ABOUT 24
HOURS AS THE NEXT COLD FRONT ARRIVES.
GIVEN THE LIGHT WINDS AND CLEAR SKIES TONIGHT...TEMPERATURES WILL
REACH THEIR DEWPOINTS. MOISTURE LOOKS A LITTLE TOO SHALLOW FOR ANY
LIGHT FOG OR VSBY REDUCTIONS AT TAF SITES...BUT FROST IS A GOOD
BET ON AIRCRAFT SITTING OUT OVERNIGHT. TR.92
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 54 30 45 41 64 / 0 5 0 0 5
WACO, TX 54 31 51 39 65 / 0 5 0 0 0
PARIS, TX 50 27 44 34 57 / 0 5 0 0 5
DENTON, TX 52 25 43 37 62 / 0 5 0 0 5
MCKINNEY, TX 51 27 44 36 61 / 0 5 0 0 5
DALLAS, TX 53 31 45 41 63 / 0 5 0 0 5
TERRELL, TX 52 30 46 37 61 / 0 5 0 0 5
CORSICANA, TX 53 32 50 39 64 / 0 5 0 0 5
TEMPLE, TX 54 32 54 39 66 / 0 5 0 0 0
MINERAL WELLS, TX 56 28 46 36 65 / 0 5 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PUEBLO CO
424 AM MST SUN JAN 17 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 423 AM MST SUN JAN 17 2016
...SNOW AND WIND CONTINUES FOR THE CENTRAL MOUNTAINS TODAY...
NEXT UPPER WAVE IS CURRENTLY MOVING INTO NW CO...AND WILL CONTINUE
TO DROP SOUTHEASTWARD INTO THE TX PANHANDLE BY MID DAY. AREA RADARS
SHOWING PERSISTENT SNOW BANKED UP INTO THE NORTHWEST FACING SLOPES
OF CHAFFEE AND LAKE COUNTY...WITH LXV REPORTING A FEW HUNDREDTHS OF
PRECIPITATION EACH HOUR. LIKELY SOME PRETTY STOUT WINDS ACROSS THE
HIGHER ELEVATIONS...AS KCCU AND K7BM ARE REPORTING GUSTS 30-35
KTS...AND IT IS LIKELY THAT GUSTS AT PEAK LEVEL ARE PROBABLY AROUND
50 KTS OR BETTER BASED ON MODEL SOUNDINGS. FREMONT PASS WEBCAM HAS
BEEN SHOWING POOR VISIBILITIES AT TIMES WITH SNOW AND BLOWING SNOW.
LATEST HIGH RES MODELS HAVE COME IN HEAVIER WITH SNOWFALL ACROSS THE
HIGHER ELEVATIONS OF THE SAWATCH AND MOSQUITO RANGES WHICH JIVES
WELL WITH ABOVE OBSERVATIONS...AND HAVE ALREADY HOISTED A WINTER
WEATHER ADVISORY FOR ZONE 58 AND 60 THROUGH TODAY. HEAVIEST SNOW
WILL FALL THIS MORNING ASSOCIATED WITH THE BETTER FORCING/CAA. THEN
PERSISTENT NORTHWEST FLOW WILL PROVIDE FAVORABLE OROGRAPHICS FOR
SNOW SHOWERS TO CONTINUE THROUGH THE AFTERNOON...THOUGH AT LESSER
RATES. THAT COMBINED WITH THE PROBABILITY FOR BLOWING SNOW TO
CONTINUE...THE WINTER WEATHER ADVISORY WILL CARRY THROUGH 5 PM THIS
EVENING.
ALSO WATCHING THE ARCTIC COLD FRONT PUSH INTO EASTERN PORTIONS OF
THE PLAINS EARLY THIS MORNING WITH STRATUS AND TEMPERATURES IN THE
TEENS PUSHING SOUTHWESTWARD. LATEST HRRR BACKS THIS AIRMASS WESTWARD
INTO THE SOUTHEAST PLAINS THROUGH THE MORNING WITH POTENTIAL FOR
STRATUS TO SPREAD AS FAR WEST AS KLHX. COULD EVEN SEE SOME LOW
CLOUDS BRIEFLY FORM AT KPUB BY LATE MORNING...BUT ASSUMING MODELS
ARE HANDLING THE WESTWARD PUSH OF THE COLDER AIR...DON`T THINK
CLOUDS WILL BECOME PERSISTENT AT KPUB. THIS WILL POSE CHALLENGES FOR
MAX TEMPS TODAY THOUGH...AS NORTHWEST WINDS AND SLIGHTLY WARMER
TEMPERATURES ACROSS THE MTS AND LOWER EASTERN SLOPES WILL TRANSITION
INTO THE COLDER AIRMASS BANKED INTO THE SOUTHEAST PLAINS. GETTING
THIS GRADIENT IN THE CORRECT POSITION WILL BE KEY TO FORECASTING MAX
TEMPERATURES TODAY...AND WITH EASTERLY SFC WINDS EXPECTED AT
KPUB...KEPT TEMPERATURES BELOW GUIDANCE FOR THE LOWER ARKANSAS RIVER
VALLEY FROM KPUB EASTWARD. WOULDN`T BE SURPRISED TO SEE HIGHS ONLY
IN THE 20S ALONG THE KS BORDER THIS AFTERNOON. HAVE ALSO INCLUDED
SOME FOG IN THE GRIDS FOR THE FAR EASTERN PLAINS...AND WILL HAVE TO
WATCH FOR THE POTENTIAL FOR IT TO BECOME DENSE...OR EVEN PRODUCE
SOME SPOTTY FREEZING DRIZZLE LATER THIS MORNING AS LOWER ATMOS
SATURATES. ANY VIS RESTRICTIONS SHOULD BREAK BY NOON...AND MODELS
SUGGEST STRATUS WILL BREAK UP DURING THE MID AFTERNOON FOR FAR
EASTERN AREAS.
TONIGHT...LEE TROF KICKS EASTWARD AND ARCTIC AIRMASS RECEDES
EASTWARD ACROSS THE PLAINS. SHOULD BE A QUICK DROP IN TEMPERATURES
THIS EVENING THOUGH...ESPECIALLY FOR THE EASTERN PLAINS.
MEANWHILE...WESTERLY WINDS ACROSS THE MTS/I-25 CORRIDOR SHOULD KEEP
MIN TEMPS IN THE MID-UPPER 20S IN THE USUAL BREEZY SPOTS LIKE CANON
CITY AND WALSENBURG. TRICKY FORECAST AGAIN FOR KALS. GUIDANCE HAS
BEEN PERSISTENTLY UNDERDOING THE AMOUNT OF RADIATIONAL COOLING AT
NIGHT OVERTOP SNOWPACK ACROSS THE SAN LUIS VALLEY...ESPECIALLY IF
CLOUDS ARE LACKING. THERE WILL BE ANOTHER BOUT OF HIGH CLOUDS
SPILLING IN OVERTOP THE UPPER RIDGE AXIS TONIGHT...BUT APPEARS THAT
BETTER MOISTURE WILL STAY OFF TO THE NORTH AND WEST...SO HAVE
UNDERCUT GUIDANCE FOR MIN TEMPS FOR THE SAN LUIS VALLEY AGAIN
TONIGHT. WILL HAVE TO WATCH FOR THE EVER PRESENT THREAT FOR PATCHY
DENSE FOG ACROSS THE SAN LUIS VALLEY TONIGHT AS WELL. -KT
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 423 AM MST SUN JAN 17 2016
...SEVERAL DISTURBANCES TO BRING SNOW TO THE MOUNTAINS...
MONDAY THROUGH WEDNESDAY...MODELS HAVE BEEN VERY CONSISTENT IN
KEEPING AN ACTIVE UPPER PATTERN IN PLACE FOR THE REGION...AND
ESPECIALLY FOR THE HIGHER ELEVATIONS WITH A FOCUS ON THE CONTDVD. ONE
DISTURBANCE WILL CROSS MONDAY NIGHT INTO TUESDAY...AND THE SECOND
WILL CROSS ON WEDNESDAY. GIVEN THE GENERAL NW FLOW ALOFT...THE
CONTDVD WILL RECEIVE THE BRUNT OF THE NEW SNOWFALL...AND
PARTICULARLY THE CENTRAL MTS. EACH EVENT SHOULD BRING 1 TO 3 INCHES
OF NEW SNOW TO THE HIGHER TERRAIN OF LAKE AND CHAFFEE COUNTIES...AND
UP TO 2 INCHES FOR THE REMAINING MTS. MAX TEMPS EACH DAY ARE
EXPECTED TO CLIMB TO NEAR 50 F FOR THE PLAINS...AND INTO THE 30S TO
NEAR 40 F FOR THE HIGH VALLEYS.
THURSDAY THROUGH SATURDAY...A RIDGE OF HIGH PRESSURE BUILDS ACROSS
THE SOUTHWESTERN US...ALLOWING FOR DRY CONDITIONS ACROSS THE CWA FOR
THU AND FRI. MAX TEMPS ON THU SHOULD BE THE SAME AS EARLIER IN THE
WEEK...BUT FOR FRI AND SAT WILL WARM TO NEAR 60 F FOR THE
PLAINS...AND INTO THE MID 30S TO MID 40S FOR THE HIGH VALLEYS.
LATEST MODEL RUNS HINT AT ANOTHER UPPER WAVE CROSSING THE REGION FOR
SAT...BRINGING ISOLATED SNOW TO THE CONTDVD. HOWEVER...AT THIS TIME
THIS FEATURE LOOKS TO BE MORE OF A GLANCING BLOW TO THE
NORTH...WHICH WOULD KEEP SNOW AMOUNTS LIGHT WITH LITTLE EFFECT ON
TEMPS EAST OF THE MTS. MOORE
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 423 AM MST SUN JAN 17 2016
IFR TO LIFR CONDITIONS WITH -SN BLSN WILL CONTINUE ACROSS THE
CENTRAL MTS TODAY WITH WIDESPREAD MTN OBSCURATIONS EXPECTED ACROSS
THE SAWATCH AND MOSQUITO RANGES. SNOW WILL BE MORE ISOLATED TO
SCATTERED IN COVERAGE THIS MORNING OVER THE REMAINDER OF THE
MOUNTAINS WITH POCKETS OF MVFR TO IFR CONDITIONS. MEANWHILE...THE
TAF SITES WILL REMAIN DRY. WILL HAVE TO WATCH FOR THE POTENTIAL
FOR SHALLOW DENSE GROUND FOG AT KALS THIS MORNING...BUT WITH SOME
MID/HIGH CLOUD COVER AT TIMES OVER THE AREA SYSTEM...SUSPECT THAT
CONDITIONS WILL REMAIN MVFR-VFR. IFR TO LIFR STRATUS/FOG WILL
SPREAD EASTWARD INTO THE SOUTHEAST PLAINS THIS MORNING BEHIND A
SHALLOW ARCTIC COLD FRONT. STRATUS IS EXPECTED TO SPREAD INTO KLHX
BY MID MORNING. THERE IS A LOW POTENTIAL FOR A SCT LOW CLOUD LAYER
TO DEVELOP FOR AN HOUR OR TWO OVER KPUB BY LATE MORNING.
OTHERWISE...CLOUDS WILL SLOWLY DIMINISH FROM WEST TO EAST ACROSS
THE PLAINS THROUGH THE AFTERNOON WITH CONDITIONS REMAINING VFR AT
KCOS AND KPUB THROUGH TONIGHT. KALS MAY SEE A BETTER SHOT FOR SOME
IFR CONDITIONS LATE TONIGHT THROUGH MONDAY MORNING DUE TO GROUND
FOG. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR COZ058-
060.
&&
$$
SHORT TERM...KT
LONG TERM...MOORE
AVIATION...KT
AREA FORECAST DISCUSSION
NWS ALBANY NY
1001 AM EST SUN JAN 17 2016
.SYNOPSIS...
ANOTHER LOW PRESSURE SYSTEM WILL APPROACH FROM THE GREAT
LAKES REGION THIS AFTERNOON...AND WILL BRING MAINLY A LIGHT SNOWFALL
TO THE AREA TONIGHT. IN THE WAKE OF THIS SYSTEM...AN ARCTIC AIRMASS
WILL MOVE INTO THE REGION WITH LOWS DROPPING INTO THE SINGLE DIGITS
AND BELOW ZERO MONDAY NIGHT. LAKE EFFECT SNOWS WILL ALSO DEVELOP
DOWNWIND OF LAKE ONTARIO MONDAY THROUGH TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1000 AM EST...THE VISIBLE SATELLITE PICTURE CONTINUES TO
HAVE CLOUDS INCREASE AHEAD OF THE CLIPPER LOW MOVING EAST OF LAKE
HURON AND GEORGIAN BAY. SOME ISOLD-SCT SNOW SHOWERS PERSIST OVER
THE TUG HILL PLATEAU/THE WRN DACKS. SOME LOW CHC POPS WERE
CONTINUED THERE LATE THIS MORNING. THE LATEST HRRR 3-KM/NAM12
TRENDS ARE FOR LIGHT SNOW TO MOVE INTO THE FCST AREA FROM THE W/SW
BTWN 21Z-00Z/MON. SOME SLIGHT RETOOLING OF THE POPS WAS DONE PRIOR
TO 00Z/MON. PRIOR TO THE WEAK ISENTROPIC LIFT WITH THE
CLIPPER...MOST OF THE AFTERNOON SHOULD BE DRY.
IT WILL BE MUCH COLDER TODAY THAN YESTERDAY WITH HIGHS RANGING
FROM THE MID 20S NORTHWEST TO MID 30S SOUTHEAST WHICH MEANS THE
TEMPERATURES WILL ONLY RISE A DEGREE OR TWO IN MOST AREAS FROM
OVERNIGHT LOWS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
A WINTER WEATHER ADVISORY FOR SNOW HAS BEEN ISSUED FOR TONIGHT FOR
NORTHERN HERKIMER AND HAMILTON COUNTIES.
A LAKE EFFECT SNOW WARNING HAS BEEN ISSUED FOR HERKIMER COUNTY
FOR MONDAY THROUGH TUESDAY.
THE CLIPPER TYPE SYSTEM WILL MOVE FROM THE EAST END OF LAKE
ONTARIO THIS EVENING TO THE GULF OF MAINE BY MONDAY MORNING.
AS A RESULT SNOW WILL OVERSPREAD THE FA THIS EVENING AND CONTINUE
THROUGH MUCH OF THE OVERNIGHT. SNOWFALL ACCUMULATIONS WILL
GENERALLY BE 1 TO 4 INCHES IN MOST AREAS WITH 3 TO 8 INCHES
ACROSS THE WESTERN ADIRONDACKS. LOWS TONIGHT WILL RANGE FROM THE
UPPER SINGLE DIGITS NORTHWEST TO AROUND 20 SOUTHEAST.
WITH THE PASSAGE OF THE SYSTEM`S ARCTIC BOUNDARY...THERE WILL BE A
TRANSITION TO LAKE EFFECT SNOWS. SIGNIFICANT LAKE EFFECT SNOW IS
EXPECTED ACROSS HERKIMER COUNTY WITH 6 TO 12 INCHES OF
ACCUMULATION BETWEEN MONDAY AND TUESDAY WITH THE GREATEST
ACCUMULATION ACROSS THE SOUTHERN PORTION OF NORTHERN HERKIMER
COUNTY AND SOUTHERN HERKIMER COUNTY WHERE THE TRAJECTORY OF THE
LAKE BAND OFF LAKE ONTARIO IS MOST PERSISTENT. ARCTIC AIR WILL
POUR INTO THE REGION AND IT WILL GET BITTERLY COLD MONDAY NIGHT
WITH WIND CHILL VALUES DOWN TO 20 BELOW OR COLDER ACROSS MUCH OF
THE WESTERN ADIRONDACKS. HAVE THIS MENTIONED IN OUR HAZARDOUS
WEATHER OUTLOOK. HIGHS ON MONDAY ARE EXPECTED TO RANGE FROM THE
TEENS NORTHWEST TO MID 20S SOUTHEAST. LOWS MONDAY NIGHT ARE
EXPECTED TO RANGE FROM THE 5 BELOW ZERO NORTHWEST TO 15 ABOVE ZERO
SOUTHEAST. HIGHS ON TUESDAY ARE EXPECTED TO RANGE FROM THE TEENS
NORTHWEST TO MID 20S SOUTHEAST.
THE LAKE EFFECT IS EXPECTED TO WIND DOWN BY TUESDAY NIGHT WITH
MOSTLY CLOUDY SKIES DURING THE EVENING GIVING WAY TO SOME BREAKS
IN THE CLOUDS OVERNIGHT. IT WILL CONTINUE TO BE COLD WITH LOWS IN
THE SINGLE DIGITS AND TEENS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE PERIOD WILL LARGELY BE DOMINATED BY SEASONABLY CHILLY
TEMPERATURES...AND BELOW NORMAL PRECIPITATION...UNTIL FRI-SAT.
THEN...THERE IS AT LEASE SOME POSSIBILITY OF A COASTAL STORM
AFFECTING PORTIONS OF THE REGION...ESPECIALLY SOUTHERN AREAS.
FOR WED-THU...SOME LINGERING LAKE EFFECT SNOW SHOWERS MAY GRAZE THE
FAR WESTERN ADIRONDACKS AND MOHAWK VALLEY...WITH GENERALLY DRY
CONDITIONS EXPECTED ELSEWHERE. A FAST MOVING...WEAKENING AND
MOISTURE STARVED UPPER LEVEL IMPULSE IS EXPECTED TO TRACK SOUTH OF
THE REGION ON THU. THIS MAY ALLOW FOR AN INCREASE IN HIGH/MID LEVEL
CLOUDS...ESP ACROSS SOUTHERN AREAS. OTHERWISE...MAX TEMPS SHOULD
REACH THE MID 20S TO LOWER 30S...EXCEPT FOR MAINLY TEENS ACROSS
HIGHER ELEVATIONS. OVERNIGHT MIN TEMPS SHOULD FALL INTO THE SINGLE
DIGITS AND TEENS.
FOR FRI-SAT...LATEST 00Z/17 DETERMINISTIC GLOBAL MODELS AND A SLIGHT
INCREASE IN 00Z/17 GEFS MEMBERS HAVE TRENDED MORE AMPLIFIED WITH
UPPER LEVEL ENERGY DIGGING INTO THE GULF COAST REGION...WITH MORE
PHASING BETWEEN SOUTHERN AND NORTHERN STREAM ENERGY COMPARED TO 24
HOURS AGO. THIS RESULTS IN A MORE NORTHERN TRACK OF A LOW PRESSURE
SYSTEM...EXPECTED TO TRANSLATE NORTHEAST FROM THE GULF COAST REGION
TO THE MID ATLANTIC COAST LATE FRI INTO SAT...WHILE DEEPENING. THE
00Z/17 DETERMINISTIC ECMWF CLOSES OFF THE MID/UPPER LEVEL LOW SOUTH
OF LONG ISLAND...WHILE THE GFS AND MOST 00Z/17 GEFS MEMBERS SUGGEST
A STRONG BUT MORE PROGRESSIVE SYSTEM. EITHER WAY...THE OVERALL
SIGNAL IS THAT SOME FORM OF A LOW PRESSURE SYSTEM MAY TRACK CLOSE
ENOUGH TO BRING SOME SNOW TO AT LEAST SOUTHERN AREAS FOR LATE FRI
INTO SAT. WHETHER THIS BECOMES A MORE WIDESPREAD AND HEAVIER
SNOWFALL SCENARIO REMAINS UNCERTAIN...ESP GIVEN THAT THIS IS THE
FIRST MODEL CYCLE WHERE THE ECMWF HAS JOINED OTHER GLOBAL MODELS
WITH A STRONGER/MORE NORTHERN TRACK...AND THAT 00Z/17 GEFS MEMBERS
STILL EXPRESS CONSIDERABLE UNCERTAINTY. FOR NOW...HAVE INDICATED CHC
POPS FOR CENTRAL AND SOUTHERN AREAS...AND SLIGHT CHC ACROSS THE
NORTH. THERMAL FIELDS APPEAR CONDUCIVE FOR SNOW AT THIS TIME...ESP
AS A SFC HIGH PASSES ACROSS EASTERN CANADA. EXPECT MAX TEMPS TO
REACH THE MID 20S TO LOWER 30S...WITH OVERNIGHT MINS MAINLY IN THE
TEENS.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
A DEVELOPING LOW PRESSURE SYSTEM ALONG THE GULF COAST WILL TRACK
NORTHEAST...TOWARD AND OFF THE MID ATLANTIC COAST THIS AFTERNOON
AND TONIGHT. IN ADDITION...A WEAKER LOW PRESSURE SYSTEM WILL
APPROACH FROM THE GREAT LAKES REGION TONIGHT. THIS SECOND SYSTEM
IS EXPECTED TO BRING SOME LIGHT SNOW OR SNOW SHOWERS TO KGFL/KALB
AND KPSF OVERNIGHT.
MAINLY VFR CONDITIONS ARE EXPECTED THROUGH AT LEAST THIS EVENING.
THE ONE EXCEPTION COULD BE SOME BRIEF PERIODS OF MVFR CIGS AT KPSF
THROUGH 15Z/SUN.
ALSO...A FEW PASSING FLURRIES WILL BE POSSIBLE THROUGH 14Z/SUN AT
KALB AND KPSF...BUT SHOULD NOT PRODUCE ANY RESTRICTIONS TO VSBY.
LATER THIS EVENING...LIGHT SNOW OR SNOW SHOWERS ASSOCIATED WITH
THE WEAK GREAT LAKES SYSTEM WILL DEVELOP BETWEEN 04Z-06Z/MON AT
KGFL/KALB AND KPSF. IFR VSBYS...AND MVFR CIGS ARE EXPECTED TO
DEVELOP DURING THIS TIME. THIS LIGHT SNOW IS EXPECTED TO DECREASE
IN AREAL COVERAGE BETWEEN 08Z-12Z/MON...WITH CONDITIONS IMPROVING
TO MVFR/VFR. HOWEVER...SCATTERED SNOW SHOWERS COULD STILL PRODUCE
BRIEF PERIODS OF IFR VSBYS THROUGH 12Z/MON. AT KPOU...MAINLY VFR
CONDITIONS ARE EXPECTED THROUGH 12Z/MON...ALTHOUGH PASSING SNOW
SHOWERS COULD CREATE BRIEF PERIODS OF MVFR/IFR VSBYS AFTER
07Z/MON.
WEST TO NORTHWEST WINDS AT 8-12 KT...AND SOME GUSTS UP TO 20 KT
WILL GRADUALLY DECREASE TO LESS THAN 5 KT BY MID MORNING. BY LATE
MORNING...WINDS WILL BE LIGHT...MAINLY FROM THE NORTHWEST TO
NORTH...AT 5-10 KT...ALTHOUGH MAY TREND INTO THE EAST/SOUTHEAST AT
TIMES AT KGFL DUE TO LOCAL TOPOGRAPHICAL EFFECTS. NORTHWEST TO
NORTH WINDS AT LESS THAN 5 KT ARE EXPECTED FOR SUNDAY EVENING.
WINDS WILL THEN BECOME WEST TO NORTHWEST AND INCREASE TO 8-12
KT...WITH GUSTS OF 20 KT OR STRONGER POSSIBLE AFTER 08Z/MON.
OUTLOOK...
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: LOW OPERATIONAL IMPACT. BREEZY NO SIG WX.
TUESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
COLDER AIR RETURNS TO THE HSA AND WILL PERSIST THROUGH THE
UPCOMING WEEK. PRECIPITATION TYPE WILL BE SNOW. ICE WILL FORM ON
BODIES OF WATER.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 AM EST
MONDAY FOR NYZ032-033.
LAKE EFFECT SNOW WARNING FROM 6 AM MONDAY TO 6 PM EST TUESDAY
FOR NYZ032-038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...IAA/11/WASULA
NEAR TERM...11/WASULA
SHORT TERM...IAA/11
LONG TERM...KL
AVIATION...KL
HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
651 AM EST SUN JAN 17 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 550 AM EST SUN JAN 17 2016
LATEST WV IMAGERY AND RAP ANALYSIS INDICATED A COLD MID/UPPER LEVEL
LOW MOVING INTO NW LAKE SUPERIOR. AT THE SFC...LAKE INDUCED TROUGH
HAS KEPT WINDS MORE NORTHERLY OVER LAKE SUPERIOR WHILE OVER UPPER MI
WINDS ARE MORE WEST TO NORTHWEST. RESULTING STRONG LOW LEVEL
CONVERGENCE FROM LAKE INDUCED TROF AND ENHANCEMENT ASSOC WITH MID-
UPR LEVEL LOW HAS RESULTED IN VERY INTENSE AND HEAVY LES BANDS INTO
ALGER AND FAR EASTERN MARQUETTE COUNTIES. REPORTS FROM ALGER COUNTY
SHERIFF IN MUNISING ESTIMATED AROUND A FOOT OF SNOW ACCMULATION
SINCE LATE SATURDAY EVENING WITH SNOWFALL RATES EXCEEDING 3 INCHES
PER HOUR AT TIMES. STRONG CONVERGENCE ALSO SUPPORTING HEAVY SNOW
BAND INTO ONTONAGON WITH SIX INCHES THIS LAST EVENING.
TODAY INTO TONIGHT...GIVEN STRONG LOW-LEVEL CONVERGENCE IN PLACE
WITH DEEP CYCLONIC N-NW FLOW AND ENHANCEMENT FROM MID-UPPER LEVEL
LOW...EXPECT HEAVY LES BANDS TO CONTINUE INTO THE LATE MORNING HOURS
FOR FAR ERN MARQUETTE COUNTY...SO DECIDED TO ISSUED A LES WARNING.
BACKING OF WINDS BEHIND PASSAGE OF SFC TROUGH SOUTH THROUGH ERN
UPPER MI THIS MORNING WILL PUSH HEAVY LES BAND OUT OF ERN MQT COUNTY
AND INTO ALGER AND NRN SCHOOLCRAFT COUNTY. STRONG LOW-LVL
CONVERGENCE SETTING UP OVER ALGER...NRN SCHOOLCRAFT AND COUNTIES
FROM PERSISTENT LAKE INDUCED TROF COMBINED WITH POTENTIAL
ENHANCEMENT FROM SHORTWAVE ROTATING SOUTH ACROSS ERN LAKE SUPERIOR
ON MONDAY WILL CONTINUE FAVORABLE ENVIRONMENT FOR HEAVY LES BANDS.
MODEL SOUNDINGS SUGGEST LAKE INDUCED CAPE NEAR 1000 J/KG AND
EQUILIBRIUM LEVEL TO NEAR 13 KFT WITH DGZ STILL FAVORABLY PLACED
WITHIN CONVECTIVE BOUNDARY LAYER YIELDING 25-30/1 SLR/S. THESE
CONDITIONS COULD EASILY SUPPORT HEAVY LES BANDS WITH SNOWFALL RATES
ON ORDER OF 1 TO 2 INCHES PER HOUR WITHIN MORE INTENSE BANDS FOR
ALGER...NRN SCHOOLCRAFT INTO LUCE COUNTIES. THUS...HAVE DECIDED TO
UPGRADE TO LES WARNINGS FOR NRN SCHOOLCRAFT AND LUCE COUNTIES
CONTINUING THROUGH MONDAY CONSISTENT WITH WARNING ALREADY IN PLACE
FOR ALGER COUNTY. SOME AREAS ACROSS ALGER AND NRN SCHOOLCRAFT COULD
SEE AN ADDITIONAL 20 INCHES OF FRESH SNOWFALL THROUGH MONDAY.
DECIDED TO ISSUE A LES ADVISORY FOR DELTA COUNTY...MAINLY OVER THE
NE PORTION WHERE MODERATE SNOW COULD ACCMULATE UP TO 6 INCHES TODAY.
ALSO ISSUED AN ADVISORY FOR SRN SCHOOLCRAFT TODAY INTO MONDAY AS
AREAS NEAR GERMFASK TO STEUBEN COULD APPROACH 8 TO MAYBE 12 INCHES
OF LES ACCUMULATION.
AS FOR WESTERN COUNTIES...GIVEN REPORT OF HEAVY SNOW IN CITY OF
ONTONAGON AND PERSISTENT STRONG LOW-LVL CONVERGENCE INTO ONTONAGON
AND TWIN LAKES PORTION OF NRN HOUGHTON COUNTY HAVE ALSO DECIDED TO
EXTEND LES WARNING FOR THESE TWO COUNTIES THROUGH MONDAY AS WELL.
BELIEVE STRONG LOW-LVL CONVERGENCE AND DEEP CYCLONIC NW FLOW WILL
OVERCOME SLIGHTLY LESS FAVORABLE DENDRITIC SNOW GROWTH. WOULD NOT BE
SURPRISED TO SEE SEVERAL LOCATIONS APPROACH A FOOT OF ADDITIONAL
SNOWFALL ESPECIALLY OVER PORCUPINE MTNS AND TWIN LAKES AREAS. IN
TURN ALSO DECIDED TO EXTEND LES ADVISORIES FOR SRN HOUGHTON FOR
ADDITIONAL ACCUMULATION OF 4 TO 8 INCHES THROUGH MONDAY.
THE VERY COLD AIR MOVING INTO INTERIOR LOCATIONS WILL DROP WIND
CHILLS INTO THE -20 TO -30 RANGE NEAR THE WI BORDER FROM IRONWOOD TO
CRYSTAL FALLS EARLY THIS MORNING AND AGAIN TONIGHT WHERE A WIND
CHILL ADVY WAS ISSUED. EXPECT ENOUGH LAKE MODERATION FARTHER NORTH
FOR WIND CHILLS MAINLY IN THE -10 TO -20 RANGE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 547 AM EST SUN JAN 17 2016
...LAKE EFFECT SNOW GRADUALLY DIMINISHES MON NIGHT INTO TUE...
UPPER TROUGH OVER THE GREAT LAKES MOVES OVER FAR EASTERN CANADA
EARLY THIS WEEK AND OFF ACROSS THE NORTH ATLANTIC BY WED WHILE
AMPLFIED ZONAL FLOW DEVELOPS OVER THE CONUS. COLD AIR WITH H85 TEMPS
DOWN TO -22C ON MON MORNING EASES BY TUE AND WED AS H85 TEMPS RISE TO
-14C BY LATE TUE INTO WED. LAKE INDUCED TROUGHING PERSISTS THROUGH
MONDAY...BUT UNLIKE THIS MORNING WITH MESOLOW ON THE
TROUGH...APPEARS THAT OVERALL RISING HEIGHTS ALOFT WILL RESULT IN
MORE OF A STEADY STATE CONVERGENT NW FLOW ON MONDAY....FOCUSING OVER
ALGER THROUGH LUCE COUNTIES. SOUNDINGS SHOW SLOWLY DIMINISHING
INSTABILITY...BUT STILL LOOKING AT INVERSIONS NEAR 5KFT OVER WESTERN
CWA AND NEAR 10KFT OVER EAST CWA. SHORTWAVE AND DEEP LAYER FORCING
DROPPING ACROSS LK SUPERIOR AND UPR MICHIGAN...ESPECIALLY EAST HALF
WILL CONTINUE TO LEAD TO HEAVY LAKE ENHANCED SNOW WITH SNOW RATES
OVER 1 INCH PER HOUR. BASED ON HOW THIS EVENT HAS WENT THUS FAR
THOUGH WITH TREMENDOUS HOURLY SNOW RATES AIDED IN LARGE PART BY VERY
HIGH SLR/S OVER 30:1...SHOULD SEE RATES 1-3 INCHES PER HOUR IN THE
HEAVIEST SNOW BANDS. BY MON AFTN...LARGER SCALE FORCING BEGINS TO
DIMINISH AS SHORTWAVE EXITS THE AREA AND Q-VECTOR DIVERGENCE MOVES
IN WITH SUBSIDENCE. INVERSIONS BEGIN TO FALL SHARPLY MON EVENING SO
EVEN THOUGH MAJORITY OF MOIST LAKE EFFECT LAYER REMAINS IN THE
DGZ...EXPECT SNOW INTENSITY TO START TAKING BIGGER HIT. AS THE SFC
RIDGE OVER THE NORTHERN PLAINS ATTEMPTS TO MOVE MORE NORTH OF LK
SUPERIOR...SFC-H925 WINDS VEER NNW FM NW SO MAY SEE SNOW SHOWERS
MOVE BACK OVER MORE AREAS NEAR LK SUPERIOR. WITH THE NEGATIVE
FACTORS MENTIONED INTENSITY SHOULD BE COMING DOWN BUT WILL KEEP POPS
HIGH FOR MAINLY LIGHT SNOW AMOUNTS. LATE ON MON NIGHT WINDS BACK
MORE NW AGAIN...SO EXPECT LAKE EFFECT TO RETURN TO NW SNOW BELTS BY
TUE MORNING WHERE IT SHOULD REMAIN UNTIL TUE NIGHT IN DIMINISHED
STATE AS WINDS BECOME OFFSHORE AS SFC RIDGE MOVES ACROSS.
AS FOR QPF/SNOW...SIMILAR TO LAST NIGHT RAMPED UP QPF/SNOW COMPARED
TO CONSENSUS AND WPC. GIVEN QPF WHICH EXCEEDED TWO TENTHS OF AN INCH
IN 6 HOURS WHERE HEAVIER SNOW BANDS WERE EXPECTED ALONG WITH SLR/S
25-30:1 YIELDED A 12 HOUR SNOWFALL OF 3-6 INCHES OVER WESTERN UPR
MICHIGAN ON MON WITH AMOUNTS MORE TOWARD 5-8 INCHES OVER
ALGER/NORTHERN SCHOOLCRAFT AND LUCE COUNTIES AS PERSISTENT HIGH
INSTABILITY LAKE EFFECT SETUP IS MORE AFFECTED DIRECTLY BY SHORTWAVE
DROPPING SOUTH ACROSS THE AREA THROUGH AT LEAST MID AFTN ON MON.
BASED ON THE HIGHER THAN EXPECTED SLR/S OF THIS EVENT THUS FAR WOULD
NOT BE SURPRISED TO SEE HIGHER SLR/S AND THUS HIGHER SNOW
AMOUNTS...AT LEAST LOCALLY. COORD WITH SHORT TERM FORECASTER AND
DECIDED TO PUT WARNINGS UP FOR NORTHERN SCHOOLCRAFT AND LUCE
COUNTIES AND EXTEND WESTERN UPR MICHIGAN WARNING THROUGH MON. ADVYS
SURROUND THESE AREAS. NO DOUBT THAT HEADLINES MAY NEED TWEAKING AS
HIGHLY MESOSCALE DETAILS FOR WHERE HEAVIEST SNOW DEVELOPS BECOMES
MORE APPARENT TONIGHT INTO MONDAY MORNING.
REST OF EXTENDED FEATURES A WARMING TREND MID TO LATE THIS WEEK. MAY
SEE SOME READINGS NEAR 30 DEGREES AGAIN BY NEXT WEEKEND. WEAK
SHORTWAVE CROSSING WESTERN GREAT LAKES ON WED. A LOT OF MID LEVEL
MOISTURE BUT LOW-LEVEL MOISTURE IS LACKING DUE TO ARCTIC HIGH VCNTY
OF UPPER GREAT LAKES. RAN WITH SLIGHT CHANCE POPS SPREADING FM WEST
TO EAST. BEST CHANCE OF SNOW WILL BE OVER KEWEENAW DUE TO THE
FORCING FM THE SYSTEM AND ENOUGH INSTABILITY FOR LAKE ENHANCED SNOW.
INVERSIONS STAY AT 5KFT OR LESS SO NOT EXPECTING HEAVIER SNOW.
ADDITIONAL SHORTWAVE MOVES THROUGH WED NIGHT INTO THU WITH WEAK
TROUGH PASSAGE TIED TO IT. MAY SEE SNOW SHOWERS INCREASING LATE THIS
WEEK CLOSER TO LK SUPERIOR THOUGH TEMPS BARELY BOTTOM OUT AT -
15C...SO LAKE EFFECT SHOULD BE ON THE LIGHTER SIDE WITH LAKE TEMPS 2-
3C.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 634 AM EST SUN JAN 17 2016
AT KIWD/KCMX...NW FLOW LAKE EFFECT CONTINUES THROUGH THE PERIOD.
EXPECT IFR VSBY DURING THE HEAVIER SNOW BANDS AT IWD TODAY...BUT
WILL STAY MVFR FOR THE MOST PART TONIGHT. IFR/LIFR VSBY WILL
CONTINUE AT KCMX THROUGH THIS FORECAST PERIOD AND THIS WILL BE A
VARIABLE CONDITION.
AT KSAW...OTHER THAN A BRIEF PERIOD OF MVFR CIGS THIS AFTERNOON...EXPECT
VFR CONDITIONS TO PREVAIL. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 550 AM EST SUN JAN 17 2016
A LOW MOVING FROM SOUTHERN ONTARIO TO QUEBEC WILL BRING COLDER AIR
ACROSS LK SUPERIOR THROUGH THE WEEKEND. BEHIND THE LOW...A TROUGH
WILL REMAIN FAIRLY STATIONARY OVER SOUTHERN LAKE SUPERIOR INTO EARLY
TUESDAY...KEEPING WIND GUSTS BETWEEN 25-30KTS WITH HIGHER GALE FORCE
GUSTS TO 35 KNOTS POSSIBLE OVER EASTERN LAKE SUPERIOR LATE THIS
AFTERNOON INTO TONIGHT. IN ADDITION...HEAVY FREEZING SPRAY IS
EXPECTED TODAY INTO MONDAY. WINDS ARE EXPECTED TO SLOWLY DIMINISH
TOWARDS THE MIDDLE OF NEXT WEEK...AS HIGH PRESSURE MOVES OVER THE
UPPER GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST MONDAY FOR MIZ002-003-
006-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ013.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ001.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ014-084.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MIZ009-010.
LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ005.
LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ007.
LAKE EFFECT SNOW WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST
MONDAY FOR MIZ007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST MONDAY FOR
LSZ263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
550 AM EST SUN JAN 17 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 550 AM EST SUN JAN 17 2016
LATEST WV IMAGERY AND RAP ANALYSIS INDICATED A COLD MID/UPPER LEVEL
LOW MOVING INTO NW LAKE SUPERIOR. AT THE SFC...LAKE INDUCED TROUGH
HAS KEPT WINDS MORE NORTHERLY OVER LAKE SUPERIOR WHILE OVER UPPER MI
WINDS ARE MORE WEST TO NORTHWEST. RESULTING STRONG LOW LEVEL
CONVERGENCE FROM LAKE INDUCED TROF AND ENHANCEMENT ASSOC WITH MID-
UPR LEVEL LOW HAS RESULTED IN VERY INTENSE AND HEAVY LES BANDS INTO
ALGER AND FAR EASTERN MARQUETTE COUNTIES. REPORTS FROM ALGER COUNTY
SHERIFF IN MUNISING ESTIMATED AROUND A FOOT OF SNOW ACCMULATION
SINCE LATE SATURDAY EVENING WITH SNOWFALL RATES EXCEEDING 3 INCHES
PER HOUR AT TIMES. STRONG CONVERGENCE ALSO SUPPORTING HEAVY SNOW
BAND INTO ONTONAGON WITH SIX INCHES THIS LAST EVENING.
TODAY INTO TONIGHT...GIVEN STRONG LOW-LEVEL CONVERGENCE IN PLACE
WITH DEEP CYCLONIC N-NW FLOW AND ENHANCEMENT FROM MID-UPPER LEVEL
LOW...EXPECT HEAVY LES BANDS TO CONTINUE INTO THE LATE MORNING HOURS
FOR FAR ERN MARQUETTE COUNTY...SO DECIDED TO ISSUED A LES WARNING.
BACKING OF WINDS BEHIND PASSAGE OF SFC TROUGH SOUTH THROUGH ERN
UPPER MI THIS MORNING WILL PUSH HEAVY LES BAND OUT OF ERN MQT COUNTY
AND INTO ALGER AND NRN SCHOOLCRAFT COUNTY. STRONG LOW-LVL
CONVERGENCE SETTING UP OVER ALGER...NRN SCHOOLCRAFT AND COUNTIES
FROM PERSISTENT LAKE INDUCED TROF COMBINED WITH POTENTIAL
ENHANCEMENT FROM SHORTWAVE ROTATING SOUTH ACROSS ERN LAKE SUPERIOR
ON MONDAY WILL CONTINUE FAVORABLE ENVIRONMENT FOR HEAVY LES BANDS.
MODEL SOUNDINGS SUGGEST LAKE INDUCED CAPE NEAR 1000 J/KG AND
EQUILIBRIUM LEVEL TO NEAR 13 KFT WITH DGZ STILL FAVORABLY PLACED
WITHIN CONVECTIVE BOUNDARY LAYER YIELDING 25-30/1 SLR/S. THESE
CONDITIONS COULD EASILY SUPPORT HEAVY LES BANDS WITH SNOWFALL RATES
ON ORDER OF 1 TO 2 INCHES PER HOUR WITHIN MORE INTENSE BANDS FOR
ALGER...NRN SCHOOLCRAFT INTO LUCE COUNTIES. THUS...HAVE DECIDED TO
UPGRADE TO LES WARNINGS FOR NRN SCHOOLCRAFT AND LUCE COUNTIES
CONTINUING THROUGH MONDAY CONSISTENT WITH WARNING ALREADY IN PLACE
FOR ALGER COUNTY. SOME AREAS ACROSS ALGER AND NRN SCHOOLCRAFT COULD
SEE AN ADDITIONAL 20 INCHES OF FRESH SNOWFALL THROUGH MONDAY.
DECIDED TO ISSUE A LES ADVISORY FOR DELTA COUNTY...MAINLY OVER THE
NE PORTION WHERE MODERATE SNOW COULD ACCMULATE UP TO 6 INCHES TODAY.
ALSO ISSUED AN ADVISORY FOR SRN SCHOOLCRAFT TODAY INTO MONDAY AS
AREAS NEAR GERMFASK TO STEUBEN COULD APPROACH 8 TO MAYBE 12 INCHES
OF LES ACCUMULATION.
AS FOR WESTERN COUNTIES...GIVEN REPORT OF HEAVY SNOW IN CITY OF
ONTONAGON AND PERSISTENT STRONG LOW-LVL CONVERGENCE INTO ONTONAGON
AND TWIN LAKES PORTION OF NRN HOUGHTON COUNTY HAVE ALSO DECIDED TO
EXTEND LES WARNING FOR THESE TWO COUNTIES THROUGH MONDAY AS WELL.
BELIEVE STRONG LOW-LVL CONVERGENCE AND DEEP CYCLONIC NW FLOW WILL
OVERCOME SLIGHTLY LESS FAVORABLE DENDRITIC SNOW GROWTH. WOULD NOT BE
SURPRISED TO SEE SEVERAL LOCATIONS APPROACH A FOOT OF ADDITIONAL
SNOWFALL ESPECIALLY OVER PORCUPINE MTNS AND TWIN LAKES AREAS. IN
TURN ALSO DECIDED TO EXTEND LES ADVISORIES FOR SRN HOUGHTON FOR
ADDITIONAL ACCUMULATION OF 4 TO 8 INCHES THROUGH MONDAY.
THE VERY COLD AIR MOVING INTO INTERIOR LOCATIONS WILL DROP WIND
CHILLS INTO THE -20 TO -30 RANGE NEAR THE WI BORDER FROM IRONWOOD TO
CRYSTAL FALLS EARLY THIS MORNING AND AGAIN TONIGHT WHERE A WIND
CHILL ADVY WAS ISSUED. EXPECT ENOUGH LAKE MODERATION FARTHER NORTH
FOR WIND CHILLS MAINLY IN THE -10 TO -20 RANGE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 547 AM EST SUN JAN 17 2016
...LAKE EFFECT SNOW GRADUALLY DIMINISHES MON NIGHT INTO TUE...
UPPER TROUGH OVER THE GREAT LAKES MOVES OVER FAR EASTERN CANADA
EARLY THIS WEEK AND OFF ACROSS THE NORTH ATLANTIC BY WED WHILE
AMPLFIED ZONAL FLOW DEVELOPS OVER THE CONUS. COLD AIR WITH H85 TEMPS
DOWN TO -22C ON MON MORNING EASES BY TUE AND WED AS H85 TEMPS RISE TO
-14C BY LATE TUE INTO WED. LAKE INDUCED TROUGHING PERSISTS THROUGH
MONDAY...BUT UNLIKE THIS MORNING WITH MESOLOW ON THE
TROUGH...APPEARS THAT OVERALL RISING HEIGHTS ALOFT WILL RESULT IN
MORE OF A STEADY STATE CONVERGENT NW FLOW ON MONDAY....FOCUSING OVER
ALGER THROUGH LUCE COUNTIES. SOUNDINGS SHOW SLOWLY DIMINISHING
INSTABILITY...BUT STILL LOOKING AT INVERSIONS NEAR 5KFT OVER WESTERN
CWA AND NEAR 10KFT OVER EAST CWA. SHORTWAVE AND DEEP LAYER FORCING
DROPPING ACROSS LK SUPERIOR AND UPR MICHIGAN...ESPECIALLY EAST HALF
WILL CONTINUE TO LEAD TO HEAVY LAKE ENHANCED SNOW WITH SNOW RATES
OVER 1 INCH PER HOUR. BASED ON HOW THIS EVENT HAS WENT THUS FAR
THOUGH WITH TREMENDOUS HOURLY SNOW RATES AIDED IN LARGE PART BY VERY
HIGH SLR/S OVER 30:1...SHOULD SEE RATES 1-3 INCHES PER HOUR IN THE
HEAVIEST SNOW BANDS. BY MON AFTN...LARGER SCALE FORCING BEGINS TO
DIMINISH AS SHORTWAVE EXITS THE AREA AND Q-VECTOR DIVERGENCE MOVES
IN WITH SUBSIDENCE. INVERSIONS BEGIN TO FALL SHARPLY MON EVENING SO
EVEN THOUGH MAJORITY OF MOIST LAKE EFFECT LAYER REMAINS IN THE
DGZ...EXPECT SNOW INTENSITY TO START TAKING BIGGER HIT. AS THE SFC
RIDGE OVER THE NORTHERN PLAINS ATTEMPTS TO MOVE MORE NORTH OF LK
SUPERIOR...SFC-H925 WINDS VEER NNW FM NW SO MAY SEE SNOW SHOWERS
MOVE BACK OVER MORE AREAS NEAR LK SUPERIOR. WITH THE NEGATIVE
FACTORS MENTIONED INTENSITY SHOULD BE COMING DOWN BUT WILL KEEP POPS
HIGH FOR MAINLY LIGHT SNOW AMOUNTS. LATE ON MON NIGHT WINDS BACK
MORE NW AGAIN...SO EXPECT LAKE EFFECT TO RETURN TO NW SNOW BELTS BY
TUE MORNING WHERE IT SHOULD REMAIN UNTIL TUE NIGHT IN DIMINISHED
STATE AS WINDS BECOME OFFSHORE AS SFC RIDGE MOVES ACROSS.
AS FOR QPF/SNOW...SIMILAR TO LAST NIGHT RAMPED UP QPF/SNOW COMPARED
TO CONSENSUS AND WPC. GIVEN QPF WHICH EXCEEDED TWO TENTHS OF AN INCH
IN 6 HOURS WHERE HEAVIER SNOW BANDS WERE EXPECTED ALONG WITH SLR/S
25-30:1 YIELDED A 12 HOUR SNOWFALL OF 3-6 INCHES OVER WESTERN UPR
MICHIGAN ON MON WITH AMOUNTS MORE TOWARD 5-8 INCHES OVER
ALGER/NORTHERN SCHOOLCRAFT AND LUCE COUNTIES AS PERSISTENT HIGH
INSTABILITY LAKE EFFECT SETUP IS MORE AFFECTED DIRECTLY BY SHORTWAVE
DROPPING SOUTH ACROSS THE AREA THROUGH AT LEAST MID AFTN ON MON.
BASED ON THE HIGHER THAN EXPECTED SLR/S OF THIS EVENT THUS FAR WOULD
NOT BE SURPRISED TO SEE HIGHER SLR/S AND THUS HIGHER SNOW
AMOUNTS...AT LEAST LOCALLY. COORD WITH SHORT TERM FORECASTER AND
DECIDED TO PUT WARNINGS UP FOR NORTHERN SCHOOLCRAFT AND LUCE
COUNTIES AND EXTEND WESTERN UPR MICHIGAN WARNING THROUGH MON. ADVYS
SURROUND THESE AREAS. NO DOUBT THAT HEADLINES MAY NEED TWEAKING AS
HIGHLY MESOSCALE DETAILS FOR WHERE HEAVIEST SNOW DEVELOPS BECOMES
MORE APPARENT TONIGHT INTO MONDAY MORNING.
REST OF EXTENDED FEATURES A WARMING TREND MID TO LATE THIS WEEK. MAY
SEE SOME READINGS NEAR 30 DEGREES AGAIN BY NEXT WEEKEND. WEAK
SHORTWAVE CROSSING WESTERN GREAT LAKES ON WED. A LOT OF MID LEVEL
MOISTURE BUT LOW-LEVEL MOISTURE IS LACKING DUE TO ARCTIC HIGH VCNTY
OF UPPER GREAT LAKES. RAN WITH SLIGHT CHANCE POPS SPREADING FM WEST
TO EAST. BEST CHANCE OF SNOW WILL BE OVER KEWEENAW DUE TO THE
FORCING FM THE SYSTEM AND ENOUGH INSTABILITY FOR LAKE ENHANCED SNOW.
INVERSIONS STAY AT 5KFT OR LESS SO NOT EXPECTING HEAVIER SNOW.
ADDITIONAL SHORTWAVE MOVES THROUGH WED NIGHT INTO THU WITH WEAK
TROUGH PASSAGE TIED TO IT. MAY SEE SNOW SHOWERS INCREASING LATE THIS
WEEK CLOSER TO LK SUPERIOR THOUGH TEMPS BARELY BOTTOM OUT AT -
15C...SO LAKE EFFECT SHOULD BE ON THE LIGHTER SIDE WITH LAKE TEMPS 2-
3C.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 124 AM EST SUN JAN 17 2016
AT KIWD/KCMX...NW FLOW LAKE EFFECT CONTINUES THROUGH THE WEEKEND.
EXPECT IFR VSBY DURING THE HEAVIER SNOW BANDS AT IWD...BUT WILL STAY
MVFR FOR THE MOST PART. IFR/LIFR VSBY AT CMX WILL CONTINUE THROUGH
THIS FORECAST PERIOD AND THIS WILL BE A VARIABLE CONDITION.
AT KSAW...MVFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE FORECAST
PERIOD WITH THE LAKE EFFECT SNOW SHOWERS STAYING MOSTLY TO THE EAST.
ONLY EXCEPTION WILL BE IFR CONDITIONS THROUGH THIS MORNING WITH
LIGHT LAKE ENHANCED SNOW CONTINUING...BUT VISIBILITY IN THE SNOW
WILL BE HIGHLY VARIABLE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 550 AM EST SUN JAN 17 2016
A LOW MOVING FROM SOUTHERN ONTARIO TO QUEBEC WILL BRING COLDER AIR
ACROSS LK SUPERIOR THROUGH THE WEEKEND. BEHIND THE LOW...A TROUGH
WILL REMAIN FAIRLY STATIONARY OVER SOUTHERN LAKE SUPERIOR INTO EARLY
TUESDAY...KEEPING WIND GUSTS BETWEEN 25-30KTS WITH HIGHER GALE FORCE
GUSTS TO 35 KNOTS POSSIBLE OVER EASTERN LAKE SUPERIOR LATE THIS
AFTERNOON INTO TONIGHT. IN ADDITION...HEAVY FREEZING SPRAY IS
EXPECTED TODAY INTO MONDAY. WINDS ARE EXPECTED TO SLOWLY DIMINISH
TOWARDS THE MIDDLE OF NEXT WEEK...AS HIGH PRESSURE MOVES OVER THE
UPPER GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST MONDAY FOR MIZ002-003-
006-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ013.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ001.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ014-084.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MIZ009-010.
LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ005.
LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ007.
LAKE EFFECT SNOW WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST
MONDAY FOR MIZ007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST MONDAY FOR
LSZ263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...07
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
548 AM EST SUN JAN 17 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 434 PM EST SAT JAN 16 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A COLD MID/UPPER LEVEL LOW
JUST NE OF WINNIPEG. AT THE SFC...WINDS WERE BACKING AHEAD OF THE
LOW WHICH HAS PUSHED THE HEAVIER LES BAND IN ERN LAKE SUPERIOR TO
THE E MUNSING. LAKE INDUCED TROUGHING EXTENDED FROM SRN INTO W CNTRL
LAKE SUPERIOR RESULTING IN THE STRONGEST LOW LEVEL CONV INTO THE
KEWEENAW NEAR HOUGHTON WHERE A VERY HEAVY LES BAND HAS PRODUCED
HIGHER SNOWFALL RATES OF A FEW INCHES PER HOUR.
TONIGHT...DEEP COLD AIR WILL CONTINUE TO SETTLE OVER THE REGION
TONIGHT WITH 850 MB TEMPS INTO THE -21C TO -25C RANGE AND 700 MB
TEMPS TO AROUND -30C. THE VERY STRONG INSTABILITY WITH LAKE INDUCED
CAPE TO 1K J/KG AND EQUILLIBRIUM HEIGHTS TO 14K FT WILL CONTINUE TO
SUPPORT THE DEVELOPMENT OF INTENSE LES BANDS. THE STRONG CONVECTION
OVER THE LAKE WILL ALSO HELP TO KEEP THE DGZ IN THE CONVECTIVE LAYER
WITH FLUFFY SNOW SLR VALUES TO AT LEAST 25/1.
AS THE MID LEVEL LOW MOVES INTO LAKE SUPERIOR...THE MODELS SUGGEST
THAT THE TROUGH TO NEAR CMX WILL GRADUALLY SINK TO THE SOUTH.
SO...ALTHOUGH HIGHER SNOWFALL RATES WILL CONTINUE...THE HEAVIER
BANDS ARE NOT EXPECTED TO REMAIN IN PLACE FOR AN EXTENDED PERIOD.
HOWEVER...ADDITIONAL SNOW AMOUNTS OF 4 TO 8 INCHES ARE EXPECTED
TONIGHT...HEAVIEST FROM CMX TO MASS CITY AND THE PORCUPINES.
OVER THE EAST...THE HEAVIEST SNOW THIS EVENING IS EXPECTED NEAR
LAKE SUPERIOR CLOSER TO PICTURED ROCKS AND GRAND MARAIS. THE HIGH
RES MODELS HAVE BEEN CONSISTENT IN SHOWING A SHARP TROUGH OR MESO LOW
DEVELOPING OVER S CNTRL LAKE SUPERIOR AND SLIDING INTO ALGER COUNTY.
STRONG LOW LEVEL CONV ASSOCIATED ON THE WRN EDGE OF THIS FEATURE WILL
BRING HEAVY LES INTO MAINLY ALGER COUNTY BTWN 06Z-12Z WITH CONTINUED
HEAVIER NNW TO NW FLOW LES BANDS SUN MORNING. THERE IS MORE
UNCERTAINTY ON HOW FAR WEST THE BAND WILL MOVE. LAND BREEZE
DEVELOPMENT SHOULD BE STRONG ENOUGH TO KEEP THE STRONGEST LES EAST OF
MARQUETTE WITH ONLY SOME LIGHTER BANDS ON THE EDGE OF THE LOW FARTHER
TO THE WEST. THE QUICK BURST OF SNOW COULD RESULT IN SNOWFALL RATES
OF 1 TO 3 INCHES PER HOUR FOR A FEW HOURS...ESPECIALY OVER WRN ALGER
COUNTY.
THE VERY COLD AIR MOVING INTO INTERIOR LOCATIONS WILL DROP WIND
CHILLS INTO THE -20 TO -30 RANGE NEAR THE WI BORDER FROM IRONWOOD TO
CRYSTAL FALLS WHERE A WIND CHILL ADVY WAS ISSUED. EXPECT ENOUGH LAKE
MODERATION FARTHER NORTH FOR WIND CHILLS MAINLY IN THE -10 TO -20
RANGE.
SUNDAY...AFTER THE BURST OF HEAVIER SNOW IN THE MORNING OVER MAINLY
WRN ALGER COUNTY...THE LES IS EXPECTED TO EVOLVE INTO LIGHT TO
MODERATE MULTIPLE WIND PARALLEL BANDS WITH A FEW HEAVIER EMBEDDED
BANDS. WHILE MORNING SNOW TOTALS COULD REACH 6 INCHES...AFTERNOON
AMOUNTS SHOULD MAINLY BE IN THE 2 TO 4 INCH RANGE.
OVER THE WEST....A SHORTER FETCH AND LESS FAVORABLE LOW LEVEL CONV
WITH THE SLOWLY BACKING NW FLOW WILL KEEP AMOUNTS IN THE 2 TO 5 INCH
RANGE. IN ADDITION...THE DGZ FALLING CLOSER TO THE LAKE SFC WILL
INHIBIT SNOW GROWTH WITH MAINLY SMALLER FLAKES THAT CAN LEAD TO LOW
VSBY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 547 AM EST SUN JAN 17 2016
...LAKE EFFECT SNOW GRADUALLY DIMINISHES MON NIGHT INTO TUE...
UPPER TROUGH OVER THE GREAT LAKES MOVES OVER FAR EASTERN CANADA
EARLY THIS WEEK AND OFF ACROSS THE NORTH ATLANTIC BY WED WHILE
AMPLFIED ZONAL FLOW DEVELOPS OVER THE CONUS. COLD AIR WITH H85 TEMPS
DOWN TO -22C ON MON MORNING EASES BY TUE AND WED AS H85 TEMPS RISE TO
-14C BY LATE TUE INTO WED. LAKE INDUCED TROUGHING PERSISTS THROUGH
MONDAY...BUT UNLIKE THIS MORNING WITH MESOLOW ON THE
TROUGH...APPEARS THAT OVERALL RISING HEIGHTS ALOFT WILL RESULT IN
MORE OF A STEADY STATE CONVERGENT NW FLOW ON MONDAY....FOCUSING OVER
ALGER THROUGH LUCE COUNTIES. SOUNDINGS SHOW SLOWLY DIMINISHING
INSTABILITY...BUT STILL LOOKING AT INVERSIONS NEAR 5KFT OVER WESTERN
CWA AND NEAR 10KFT OVER EAST CWA. SHORTWAVE AND DEEP LAYER FORCING
DROPPING ACROSS LK SUPERIOR AND UPR MICHIGAN...ESPECIALLY EAST HALF
WILL CONTINUE TO LEAD TO HEAVY LAKE ENHANCED SNOW WITH SNOW RATES
OVER 1 INCH PER HOUR. BASED ON HOW THIS EVENT HAS WENT THUS FAR
THOUGH WITH TREMENDOUS HOURLY SNOW RATES AIDED IN LARGE PART BY VERY
HIGH SLR/S OVER 30:1...SHOULD SEE RATES 1-3 INCHES PER HOUR IN THE
HEAVIEST SNOW BANDS. BY MON AFTN...LARGER SCALE FORCING BEGINS TO
DIMINISH AS SHORTWAVE EXITS THE AREA AND Q-VECTOR DIVERGENCE MOVES
IN WITH SUBSIDENCE. INVERSIONS BEGIN TO FALL SHARPLY MON EVENING SO
EVEN THOUGH MAJORITY OF MOIST LAKE EFFECT LAYER REMAINS IN THE
DGZ...EXPECT SNOW INTENSITY TO START TAKING BIGGER HIT. AS THE SFC
RIDGE OVER THE NORTHERN PLAINS ATTEMPTS TO MOVE MORE NORTH OF LK
SUPERIOR...SFC-H925 WINDS VEER NNW FM NW SO MAY SEE SNOW SHOWERS
MOVE BACK OVER MORE AREAS NEAR LK SUPERIOR. WITH THE NEGATIVE
FACTORS MENTIONED INTENSITY SHOULD BE COMING DOWN BUT WILL KEEP POPS
HIGH FOR MAINLY LIGHT SNOW AMOUNTS. LATE ON MON NIGHT WINDS BACK
MORE NW AGAIN...SO EXPECT LAKE EFFECT TO RETURN TO NW SNOW BELTS BY
TUE MORNING WHERE IT SHOULD REMAIN UNTIL TUE NIGHT IN DIMINISHED
STATE AS WINDS BECOME OFFSHORE AS SFC RIDGE MOVES ACROSS.
AS FOR QPF/SNOW...SIMILAR TO LAST NIGHT RAMPED UP QPF/SNOW COMPARED
TO CONSENSUS AND WPC. GIVEN QPF WHICH EXCEEDED TWO TENTHS OF AN INCH
IN 6 HOURS WHERE HEAVIER SNOW BANDS WERE EXPECTED ALONG WITH SLR/S
25-30:1 YIELDED A 12 HOUR SNOWFALL OF 3-6 INCHES OVER WESTERN UPR
MICHIGAN ON MON WITH AMOUNTS MORE TOWARD 5-8 INCHES OVER
ALGER/NORTHERN SCHOOLCRAFT AND LUCE COUNTIES AS PERSISTENT HIGH
INSTABILITY LAKE EFFECT SETUP IS MORE AFFECTED DIRECTLY BY SHORTWAVE
DROPPING SOUTH ACROSS THE AREA THROUGH AT LEAST MID AFTN ON MON.
BASED ON THE HIGHER THAN EXPECTED SLR/S OF THIS EVENT THUS FAR WOULD
NOT BE SURPRISED TO SEE HIGHER SLR/S AND THUS HIGHER SNOW
AMOUNTS...AT LEAST LOCALLY. COORD WITH SHORT TERM FORECASTER AND
DECIDED TO PUT WARNINGS UP FOR NORTHERN SCHOOLCRAFT AND LUCE
COUNTIES AND EXTEND WESTERN UPR MICHIGAN WARNING THROUGH MON. ADVYS
SURROUND THESE AREAS. NO DOUBT THAT HEADLINES MAY NEED TWEAKING AS
HIGHLY MESOSCALE DETAILS FOR WHERE HEAVIEST SNOW DEVELOPS BECOMES
MORE APPARENT TONIGHT INTO MONDAY MORNING.
REST OF EXTENDED FEATURES A WARMING TREND MID TO LATE THIS WEEK. MAY
SEE SOME READINGS NEAR 30 DEGREES AGAIN BY NEXT WEEKEND. WEAK
SHORTWAVE CROSSING WESTERN GREAT LAKES ON WED. A LOT OF MID LEVEL
MOISTURE BUT LOW-LEVEL MOISTURE IS LACKING DUE TO ARCTIC HIGH VCNTY
OF UPPER GREAT LAKES. RAN WITH SLIGHT CHANCE POPS SPREADING FM WEST
TO EAST. BEST CHANCE OF SNOW WILL BE OVER KEWEENAW DUE TO THE
FORCING FM THE SYSTEM AND ENOUGH INSTABILITY FOR LAKE ENHANCED SNOW.
INVERSIONS STAY AT 5KFT OR LESS SO NOT EXPECTING HEAVIER SNOW.
ADDITIONAL SHORTWAVE MOVES THROUGH WED NIGHT INTO THU WITH WEAK
TROUGH PASSAGE TIED TO IT. MAY SEE SNOW SHOWERS INCREASING LATE THIS
WEEK CLOSER TO LK SUPERIOR THOUGH TEMPS BARELY BOTTOM OUT AT -
15C...SO LAKE EFFECT SHOULD BE ON THE LIGHTER SIDE WITH LAKE TEMPS 2-
3C.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 124 AM EST SUN JAN 17 2016
AT KIWD/KCMX...NW FLOW LAKE EFFECT CONTINUES THROUGH THE WEEKEND.
EXPECT IFR VSBY DURING THE HEAVIER SNOW BANDS AT IWD...BUT WILL STAY
MVFR FOR THE MOST PART. IFR/LIFR VSBY AT CMX WILL CONTINUE THROUGH
THIS FORECAST PERIOD AND THIS WILL BE A VARIABLE CONDITION.
AT KSAW...MVFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE FORECAST
PERIOD WITH THE LAKE EFFECT SNOW SHOWERS STAYING MOSTLY TO THE EAST.
ONLY EXCEPTION WILL BE IFR CONDITIONS THROUGH THIS MORNING WITH
LIGHT LAKE ENHANCED SNOW CONTINUING...BUT VISIBILITY IN THE SNOW
WILL BE HIGHLY VARIABLE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 434 PM EST SAT JAN 16 2016
A LOW MOVING FROM SOUTHERN ONTARIO TO QUEBEC WILL BRING COLDER AIR
ACROSS LK SUPERIOR THROUGH THE WEEKEND. BEHIND THE LOW...A TROUGH
WILL REMAIN FAIRLY STATIONARY OVER SOUTHERN LAKE SUPERIOR INTO
TUESDAY...KEEPING WIND GUSTS BETWEEN 25-30KTS. IN ADDITION...THERE
IS THE POTENTIAL FOR HEAVY FREEZING SPRAY SUNDAY INTO MONDAY. WINDS
ARE EXPECTED TO SLOWLY DIMINISH TOWARDS THE MIDDLE OF NEXT WEEK...AS
HIGH PRESSURE MOVES OVER THE UPPER GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST MONDAY FOR MIZ002-003-
006-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ013.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ001.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ014-084.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MIZ009-010.
LAKE EFFECT SNOW WARNING UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ005.
LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ007.
LAKE EFFECT SNOW WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST
MONDAY FOR MIZ007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST MONDAY FOR
LSZ263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
611 AM CST SUN JAN 17 2016
.AVIATION...
VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH MONDAY
MORNING.
SOME PATCHY SHALLOW FOG/FREEZING FOG IS EXPECTED AROUND NORTH AND
CENTRAL TEXAS THIS MORNING BUT VISIBILITIES SHOULD REMAIN ABOVE 5
MILES AT ALL TERMINALS.
HIGH CLOUDS WILL INCREASE ACROSS NORTH AND CENTRAL TEXAS TODAY AS
A FAST MOVING SHORTWAVE APPROACHES FROM THE WEST. THE SHORTWAVE
TROUGH AXIS WILL MOVE EAST OF THE INTERSTATE 35 CORRIDOR THIS
EVENING AND ALLOW A COLD FRONT TO MOVE SOUTH THROUGH THE REGION.
SOUTHERLY WINDS TODAY WILL BECOME SOUTHEAST BY LATE AFTERNOON.
THE WIND WILL TURN TO THE NORTHEAST AFTER THE FRONT MOVES THROUGH
BETWEEN 5Z AND 7Z TONIGHT. WIND SPEEDS THROUGH MONDAY MORNING
WILL REMAIN BELOW 12 KNOTS.
79
&&
.PREV DISCUSSION... /ISSUED 301 AM CST SUN JAN 17 2016/
COLD MORNING IN PROGRESS ACROSS NORTH TEXAS AS A SURFACE HIGH
PRESSURE CENTER MOVES ACROSS THE REGION. WINDS HAVE GONE CALM IN
MANY LOCATIONS AND SURFACE MOISTURE LINGERS. THIS HAS RESULTED IN
AREAS OF SHALLOW FOG IN SOME LOCATIONS. IN OTHERS...WHERE T/TD
SPREADS ARE A LITTLE HIGHER...THICK FROST HAS DEVELOPED. THE FOG
SHOULD BE PATCHY AND SHALLOW AT BEST AND DOES NOT REALLY APPEAR
THAT IT WILL DEPOSIT ICE ON ANY AREA ROADS. AFTER A COLD START...
TEMPERATURES SHOULD REBOUND NICELY INTO THE LOW TO MID 50S BY THIS
AFTERNOON.
THE WARMUP WILL BE BRIEF AS ANOTHER COLD FRONT IS EXPECTED TO MOVE
THROUGH NORTH TEXAS TONIGHT INTO MONDAY MORNING. A LARGE UPPER LOW
WILL BE MOVING THROUGH THE GREAT LAKES REGION DURING THIS TIME AND
WILL ALLOW A 1030MB SURFACE HIGH TO BUILD SOUTHWARD THROUGH THE
PLAINS. TEMPERATURES ARE VERY COLD ACROSS THE UPPER PLAINS WITH
READINGS IN THE -10 TO -20F RANGE ACROSS PARTS OF THE DAKOTAS AND
MINNESOTA. WHILE THE BRUNT OF THE COLDEST AIR WILL STAY WELL TO
OUR NORTHEAST...THE PATTERN IS FAVORABLE TO ALLOW SHALLOW VERY
COLD AIR TO SPILL SOUTHWARD THROUGH THE PLAINS TODAY. AS IS
TYPICAL WITH VERY SHALLOW COLD AIR...THE MODELS ARE USUALLY TOO
WARM WITH TEMPERATURES DUE TO THEIR LACK OF LOW LEVEL RESOLUTION.
THE LATEST HIGH RESOLUTION RAP GUIDANCE DOES GIVE A SMALL HINT
THAT THE AIR MAY BE COLDER ON MONDAY ACROSS NORTH TEXAS THAN
CURRENTLY INDICATED BY THE GFS/NAM/ECMWF. THE LATEST RUN HAS
TEMPERATURES ACROSS PARTS OF CENTRAL OKLAHOMA IN THE LOW 20S ON
SUNDAY EVENING. THIS IS ABOUT 10 DEGREES COLDER THAN THE CURRENT
MOS GUIDANCE. WITH THAT IN MIND...WILL UNDERCUT THE MOS HIGHS FOR
MONDAY...PARTICULARLY NORTH OF I-20. WHILE COLD AIR WILL SPILL
INTO NORTH TEXAS...THE TRAJECTORY OF THE SURFACE HIGH AND THE
PROGRESSIVE NATURE OF THE UPPER PATTERN WILL ENSURE THAT IT WILL
BE SHORT LIVED ACROSS THE REGION. MOSTLY SUNNY SKIES AND A RETURN
TO SOUTHERLY FLOW LATE IN THE DAY ON MONDAY WILL LIKELY MIX SOME
OF THE COLDER AIR BEFORE THE SUN SETS. TEMPERATURES ARE LIKELY TO
BE IN THE LOW/MID 40S ACROSS THE NORTHERN HALF OF THE CWA WITH
UPPER 40S AND LOWER 50S SOUTH OF I-20.
THERE WILL BE SEVERAL SHORTWAVE TROUGHS THAT MOVE THROUGH THE
PLAINS THROUGH NEXT WEEK AND TIMING EACH ONE IS PROVING TO BE
RATHER DIFFICULT. THERE IS STILL QUITE A BIT OF SPREAD IN MODEL
GUIDANCE THROUGH THE END OF THE WEEK. IT DOES APPEAR THAT LOW
LEVEL FLOW WILL BECOME MORE SOUTH/SOUTHWEST ON TUESDAY WHICH WILL
ALLOW FOR A QUICK WARMUP IN TEMPERATURES BACK INTO THE 60S. A WEAK
COLD FRONT WILL MOVE THROUGH ON WEDNESDAY WITH ANOTHER COOL DOWN
BACK TOWARD SEASONAL NORMS. THERE IS A SMALL CHANCE FOR SHOWERS
ALONG THIS FRONT...MAINLY IN OUR SOUTH/SOUTHEAST COUNTIES ALTHOUGH
MOISTURE IS SOMEWHAT LIMITED. SLIGHTLY BETTER RAIN CHANCES APPEAR
TO ARRIVE LATE WEDNESDAY INTO EARLY THURSDAY AS A STRONG SHORTWAVE
MOVES THROUGH THE SOUTHERN PLAINS. THIS RESULTS IN ANOTHER SURFACE
LOW TRACKING ACROSS NORTH TEXAS WITH SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS EXPECTED TO DEVELOP ON THE EAST SIDE OF THE
LOW. A QUICK LOOK AT THE 00Z ENSEMBLE GUIDANCE INDICATES THIS
SHORTWAVE AND ASSOCIATED SURFACE FEATURES IN MOST OF THE ENSEMBLE
MEMBERS...HOWEVER THE TRACK IS QUITE VARIED WITH ABOUT HALF OF
THE GUIDANCE INDICATING RAIN/STORMS ACROSS OUR AREA...AND THE
OTHER HALF FARTHER EAST INTO THE ARKLATEX. THIS RESULTS IN A LOWER
OVERALL CONFIDENCE IN RAIN MIDWEEK BUT WE WILL MAINTAIN 20/30 POPS
LATE WEDNESDAY INTO THURSDAY WITH BEST CHANCES EAST OF INTERSTATE
35.
TEMPERATURES WILL GENERALLY REMAIN WITHIN 5 DEGREES OR SO OF
SEASONAL NORMS THROUGH THE WEEK.
DUNN
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 54 30 45 41 64 / 0 5 0 0 5
WACO, TX 54 31 51 39 65 / 0 5 0 0 0
PARIS, TX 50 27 44 34 57 / 0 5 0 0 5
DENTON, TX 52 25 43 37 62 / 0 5 0 0 5
MCKINNEY, TX 51 27 44 36 61 / 0 5 0 0 5
DALLAS, TX 53 31 45 41 63 / 0 5 0 0 5
TERRELL, TX 52 30 46 37 61 / 0 5 0 0 5
CORSICANA, TX 53 32 50 39 64 / 0 5 0 0 5
TEMPLE, TX 54 32 54 39 66 / 0 5 0 0 0
MINERAL WELLS, TX 56 28 46 36 65 / 0 5 0 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
79/91
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
140 PM PST SUN JAN 17 2016
.SYNOPSIS...A STRONG STORM SYSTEM WILL SPREAD RAIN ACROSS THE
REGION TODAY THROUGH MONDAY MORNING. A PERIOD OF HEAVY RAIN IS
LIKELY...BEGINNING IN THE NORTH BAY THIS AFTERNOON AND ACROSS
THE REMAINDER OF THE FORECAST AREA TONIGHT AND EARLY MONDAY. A
SECOND STORM WILL PRODUCE MORE RAINFALL AND LOCALLY STRONG WINDS
LATE MONDAY NIGHT THROUGH TUESDAY. THERE MAY BE A BRIEF PERIOD OF
DRY WEATHER AROUND THE MIDDLE OF THE WEEK BEFORE ANOTHER STORM
SYSTEM ARRIVES LATE IN THE WEEK.
&&
.DISCUSSION...AS OF 01:35 PM PST SUNDAY...THE MAIN STORY THROUGH
THE ENTIRE FORECAST IS ACTIVE WEATHER CONTINUES. A SERIES OF STORMS WILL
CONTINUE TO BRING PERIODS RAIN TO THE ENTIRE BAY AREA.
IN THE SHORT TERM...THE MAIN FOCUS CONTINUES TO BE THE ATMOSPHERICRIVER
SLOWLY MARCHING SOUTHWARD DOWN THE CALIFORNIA COAST. SINCE THIS
MORNING...RADAR ECHOES HAVE INCREASED SUBSTANTIALLY OVER THE NORTH
BAY AND OFF THE COAST. SINCE THIS MORNING...A FEW HUNDREDTHS TO A
TENTH OR TWO OF RAIN HAS FALLEN. EXPECT THIS TO CHANGE AS A COLD
FRONT AND ASSOCIATED MOISTURE PLUME MOVES SOUTH OVER THE BAY AREA
THIS AFTERNOON INTO TONIGHT. LATEST SATELLITE IMAGERY SHOWS THAT
PWATS OF 1.5 INCHES ARE LURKING OFF THE COAST...SO THERE IS
DEFINITELY MOISTURE TO WORK WITH. ALL THAT BEING SAID...ONLY
MINOR TWEAKS TO THE PREVIOUS FORECAST. BASED ON THE LATEST MODELS
AND SATELLITE TIMING...THE FRONT WILL MOVE INTO THE N BAY CLOSE TO
0-6Z TONIGHT AND JUST NORTH OF SAN JOSE BY 12Z MONDAY AND THEN
MONTEREY BY 18Z. GIVEN THE AMPLE MOISTURE...THERE WILL LIKELY BE A
PERIOD OF MODERATE TO HEAVY RAIN WITH THE FROPA. RAINFALL TOTALS
1.0-2.5 INCHES LOCALLY UP TO 3.5 INCHES WILL BE POSS OVER THE N
BAY/SANTA CRUZ MTS/BIG SUR COAST...ELSEWHERE 0.25 TO 1 INCH. GIVEN
THE POSSIBILITY OF MODERATE TO HEAVY RAIN WILL LEAVE FLASH FLOOD
WATCH AS IS FOR THE NORTH BAY. OTHER POTENTIAL HYDRO PROBLEMS
COULD ARISE IN THE COASTAL MOUNTAINS OF MONTEREY/SANTA CRUZ WHERE
HIGHER RAINFALL AMOUNTS ARE EXPECTED. HOWEVER...CONF IS NOT HIGH
ENOUGH TO WARRANT A FLASH FLOOD WATCH. ADDITIONALLY...LARGE SURF
IS STILL FORECAST TO ARRIVE LATER TODAY. THE COMBINATION OF LARGE
SURF...EXCESSIVE RUNOFF AND HIGH TIDE WILL LEAD TO SOME COASTAL
FLOODING. THEREFORE...THE COASTAL FLOOD WARNING REMAINS IN EFFECT
THIS AFTERNOON THROUGH MONDAY MORNING. LASTLY...THERE WILL BE A
BRIEF PERIOD OF GUSTY WINDS...BUT DEFINITELY BELOW ADVISORY
LEVELS. IN SUMMARY...THE BULK OF THE RAIN HAS YET TO ARRIVE AND
THE HEAVIEST WILL LIKELY OCCUR FROM 06-15Z MONDAY.
FOR MONDAY...THE COLD FRONT WILL MOVE SOUTHWARD AND EXIT THE CWA
LEAVING SHOWERS BEHIND IT. BRIEF BREAK IN THE ACTION SO TO SPEAK
MONDAY AFTERNOON AND MONDAY NIGHT BEFORE ANOTHER SYSTEM ARRIVES
TUESDAY. SPEAKING OF MONDAY NIGHT...LATEST GUIDANCE HAS HAD A
DRYING TREND MONDAY NIGHT. THEREFORE...TRIMMED BACK ON POPS 00-12Z
TUESDAY.
RAIN WILL RE-DEVELOP OVER THE NORTH BAY EARLY TUESDAY MORNING
THEN SPREAD SOUTHWARD THROUGH THE DAY. THE HEAVIEST RAINFALL WILL
ONCE AGAIN BE OVER THE NORTH BAY AND COASTAL MOUNTAINS...1-2
INCHES. LOWER ELEVATIONS 0.25-0.75 INCHES BY TUESDAY NIGHT.
MODELS CONTINUE TO ADVERTISE A BRIEF BREAK WITH SHORTWAVE RIDGING
ON WEDNESDAY AND WEDNESDAY NIGHT. THE RIDGE SHIFTS EAST WITH
ANOTHER ROUND OF RAIN EXPECTED THURSDAY NIGHT INTO FRIDAY...WITH
MORE RAIN POSSIBLE NEXT WEEKEND.
&&
.AVIATION...AS OF 9:30 AM PST SUNDAY...MAIN FOCUS FOR THE 18Z
PACKAGE WAS FOR TIMING OF THE RAIN AS A FRONT MOVES THROUGH OUR
AREA TODAY AND TONIGHT. LAST THREE RUNS OF THE HRRR HAVE ONLY
SLIGHTLY CHANGED, SO CONFIDENCE IN THE TIMING LISTED IN THE TAF IS
FAIRLY HIGH. WINDS ALSO ON TRACK TO INCREASE AS THE FRONT NEARS.
RAIN ENDS NEAR THE END OR JUST OUTSIDE OF THE TAF PACKAGE.
MODERATE TO HIGH CONFIDENCE FOR TIMING. MODERATE CONFIDENCE ON
VIS AND CIG HEIGHTS.
VICINITY OF KSFO...MVFR CIGS FORECAST THROUGH MOST OF THE PERIOD.
-RA RETURN AROUND 23Z OR 0Z WITH POTENTIAL FOR RA OR EVEN +RA AT
OR A BIT AFTER 04Z. WINDS OF 170 TO 190 AROUND 10 KT. SPEEDS WILL
INCREASE WITH GUSTS OVER 20 KT POSSIBLE AFTER 23Z. MODERATE TO
HIGH CONFIDENCE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MOSTLY MVFR VFR CONDITIONS THROUGH
THE DAY WITH -RA EXPECTED AFTER 04Z. WINDS GENERALLY 170 TO 190 AT
KMRY TO 10 KT. AT KSNS WINDS OF 130 TO 150 FORECAST WITH GUSTS
OVER 20 KT AFTER 02Z. MODERATE CONFIDENCE.
&&
.BEACHES...AS OF 10:00 AM PST SUNDAY... AN APPROACHING LONG PERIOD
WEST SWELL WILL BRING HAZARDOUS CONDITIONS TO REGIONAL BEACHES
THROUGH MONDAY. WEST SWELLS WILL STEADILY INCREASE TO 16 TO 19 FEET
WITH A PERIOD OF 17 TO 19 SECONDS TODAY. EXTREME WAVE RUN UP IS
EXPECTED WITH THIS SWELL AS LONG LULLS IN BETWEEN WAVE SETS WILL
INCREASE RISK OF DEADLY RIP CURRENTS...LARGE SNEAKER WAVES... AND
THE LIKELIHOOD OF BEING WASHED INTO SEA BY A WAVE. SMALL VESSELS
ALONG THE IMMEDIATE COAST MAY ALSO BE PUSHED INTO COASTAL ROCKS.
DURING HIGH TIDE... COASTAL INUNDATION MAY CUT OFF ACCESS TO SOME
BEACHES AND OUTCROPPINGS. THE LARGE WAVES WILL GRADUALLY TAPER OFF
EARLY NEXT WEEK.
&&
.MARINE...AS OF 08:33 AM PST SUNDAY...LOOK FOR INCREASING
SOUTHERLY WINDS TODAY AS A SYSTEM MOVES THROUGH. THE STRONGEST
WINDS WILL BE OVER THE NORTHERN WATERS. WINDS WILL DECREASE
TONIGHT AFTER THE FRONT PASSES BUT ANOTHER SYSTEM WILL INCREASE
THE WINDS AGAIN TUESDAY. A LARGE SWELL TRAIN GENERATED BY THESE
SERIES OF STORMS WILL AFFECT THE WATERS THROUGH AT LEAST MONDAY
MORNING.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...COASTAL FLOOD WARNING...ALL COASTAL ZONES AS WELL AS NORTH
BAY ZONES BORDERING SF BAY.
HIGH SURF WARNING...ALL COASTAL ZONES FROM SONOMA TO
MONTEREY COUNTY.
FLASH FLOOD WATCH...NORTH BAY COUNTIES OF SONOMA...NAPA
AND MARIN.
SCA...PIGEON PT TO PT PINOS 0-10 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PT REYES TO PIGEON PT 0-10 NM
SCA...PT ARENA TO PIGEON PT 10-60 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: MM
AVIATION: BELL
MARINE: BELL
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
958 AM PST SUN JAN 17 2016
.SYNOPSIS...A STRONG STORM SYSTEM WILL SPREAD RAIN ACROSS THE
REGION TODAY THROUGH MONDAY MORNING. A PERIOD OF HEAVY RAIN IS
LIKELY...BEGINNING IN THE NORTH BAY THIS AFTERNOON AND ACROSS
THE REMAINDER OF THE FORECAST AREA TONIGHT AND EARLY MONDAY. A
SECOND STORM WILL PRODUCE MORE RAINFALL AND LOCALLY STRONG WINDS
LATE MONDAY NIGHT THROUGH TUESDAY. THERE MAY BE A BRIEF PERIOD OF
DRY WEATHER AROUND THE MIDDLE OF THE WEEK BEFORE ANOTHER STORM
SYSTEM ARRIVES LATE IN THE WEEK.
&&
.DISCUSSION...AS OF 09:06 AM PST SUNDAY...SHORT TERM CONCERNS
WILL CONTINUE TO FOCUS ON THE APPROACHING COLD FRONT AND VERY
ROBUST MOISTURE PLUME CURRENTLY POINTED NORCAL. OVERNIGHT THE RAIN
BUCKETS IN THE NORTH BAY HAVE BEEN STEADILY TIPPING WITH VENADO
WELL OVER AN INCH WITH MANY OTHER LOCATIONS IN THE 0.25 TO 0.5
INCH RANGE. THE LATEST KMUX RADAR IMAGERY MAY NOT BE OVERLY
IMPRESSIVE FOR THE NORTH BAY...BUT RAIN IS STILL BEING REPORTED.
THERE HAVE ALSO BEEN A FEW REPORTS OF MEASURABLE RAIN OVER
PORTIONS OF CONTRA COSTA COUNTY.
FOR THE REST OF TODAY...THE COLD FRONT WILL CONTINUE TO SLOWLY
MOVE SOUTHWARD. THE LATEST HRRR ACTUALLY HANDLES THIS FAIRLY WELL
WITH THE BULK OF THE PRECIP NOT ARRIVING UNTIL LATER THIS
AFTERNOON. DID A QUICK UPDATE TO THE FORECAST TO SLOW DOWN THE
ONSET OF THE HEAVIER PRECIP TODAY AND TO LOWER RAINFALL AMOUNTS
THIS MORNING. FOR MORE SPECIFIC DETAILS ON THE WEATHER SYSTEM SEE
BELOW.
&&
.PREV DISCUSSION...AS OF 3:30 AM PST SUNDAY...EARLY MORNING IR
SATELLITE IMAGERY SHOWS A FRONTAL BOUNDARY EXTENDING FROM THE FAR
NORTHERN CALIFORNIA COAST WSW OVER THE PACIFIC. THE MOISTURE PLUME
COINCIDENT WITH THIS BOUNDARY CONTAINS PRECIPITABLE WATER VALUES
EXCEEDING 1.5 INCHES WITH A MAXIMUM OF 2 INCHES. A STRONG
SHORTWAVE TROUGH CURRENTLY RIDING ALONG THE FRONTAL BOUNDARY HAS
RESULTED IN STRONG ENHANCEMENT OF THE FRONT JUST OFF THE NORTHERN
CA COAST NORTH OF CAPE MENDOCINO...WITH EMBEDDED CONVECTION AND
NUMEROUS LIGHTNING STRIKES IN THAT AREA. THE MODELS HAVE BEEN
CONSISTENT IN GRADUALLY SLIDING THE FRONTAL BOUNDARY AND
ASSOCIATED ENHANCED RAINFALL SOUTH THROUGH OUR FORECAST AREA LATER
TODAY AND TONIGHT. THE LATEST MODELS HAVE DELAYED THE ONSET OF
HEAVIEST RAINFALL A BIT. BASED ON A CONSENSUS OF THE MODELS...THE
HEAVIEST RAINFALL IN THE NORTH BAY IS EXPECTED FROM EARLY THIS
AFTERNOON THROUGH EARLY EVENING...THEN FROM EARLY EVENING THROUGH
LATE TONIGHT FOR THE REST OF THE SF BAY AREA AND SANTA CRUZ
COUNTY...AND FROM ABOUT MIDNIGHT THROUGH SUNRISE MONDAY MORNING
FOR MONTEREY AND SAN BENITO COUNTIES. RAIN RATES ARE EXPECTED TO
BE HEAVY FOR A FEW HOURS WHILE THE FRONTAL BOUNDARY MOVES THROUGH.
THE MAIN CONCERN IS WHETHER THE BAND OF HEAVY RAIN WILL SLOW
SIGNIFICANTLY OR STALL IN ONE PARTICULAR AREA. THE 00Z NAM
INDICATED A WAVE WOULD DEVELOP ALONG THE FRONT EARLY THIS EVENING
AND MAINTAIN HEAVY RAIN RATES IN THE NORTH BAY FOR A MORE
PROLONGED PERIOD OF TIME. THE 06Z NAM DELAYS THE DEVELOPMENT OF
THIS FRONTAL WAVE AND INSTEAD STALLS THE BAND OF HEAVIER RAIN
ACROSS SANTA CRUZ COUNTY AND THE SOUTH BAY OVERNIGHT. ON THE OTHER
HAND...BOTH THE GFS AND ECMWF MOVE THE FRONTAL BOUNDARY THROUGH
OUR ENTIRE AREA AT A STEADY PACE. IN ANY CASE...ALL OF THE MODELS
INDICATE THAT THE GREATEST RAINFALL TOTALS THROUGH MIDDAY MONDAY
WILL BE ACROSS THE NORTH BAY. WILL THEREFORE CONTINUE WITH A FLASH
FLOOD WATCH FOR SONOMA...NAPA AND MARIN COUNTIES THROUGH LATE
TONIGHT.
FOR AREAS SOUTH OF THE GOLDEN GATE....AT LEAST MINOR HYDRO ISSUES
ARE LIKELY TONIGHT...ESPECIALLY IN THE SANTA CRUZ MOUNTAINS AND
SOUTH BAY IF THE 06Z NAM WERE TO VERIFY. WILL CONTINUE TO
HIGHLIGHT THE POSSIBILITY OF MINOR URBAN AND/OR SMALL STREAM
FLOODING WITH A HAZARDOUS WEATHER OUTLOOK FOR ALL AREAS NOT
INCLUDED IN THE FLASH FLOOD WATCH. IN ADDITION...A COMBINATION OF
LARGE POWERFUL OCEAN SWELL AND HEAVY RAINFALL RUNOFF WILL LIKELY
PRODUCE AT LEAST MINOR COASTAL FLOODING...PARTICULARLY AROUND THE
TIMES OF HIGH TIDE NEAR 6 PM THIS EVENING AND THEN AGAIN AROUND 6
AM ON MONDAY MORNING. A COASTAL FLOOD WARNING IS IN EFFECT FROM 4
PM TODAY UNTIL 7 AM MONDAY FOR ALL COASTAL ZONES AS WELL AS AREAS
AROUND THE NORTHERN SAN FRANCISCO BAY...PARTICULARLY BAYSIDE
LOCATIONS OF MARIN COUNTY.
WINDS WITH THIS SYSTEM ARE NOT EXPECTED TO REACH ADVISORY LEVELS.
THERE WILL BE MODERATELY STRONG AND GUSTY SOUTHERLY WINDS NEAR THE
COAST AND LOCALLY IN THE HILLS FROM THIS AFTERNOON THROUGH
TONIGHT...WHEN WIND GUSTS UP TO 35 MPH ARE POSSIBLE.
INDICATIONS ARE THAT RAINFALL WILL TAPER OFF PRETTY QUICKLY ON
MONDAY MORNING AND MOSTLY END BY MONDAY AFTERNOON. THERE WILL BE
ONLY A SHORT BREAK IN THE ACTION BEFORE THE NEXT SYSTEM SWEEPS IN
LATE MONDAY NIGHT AND TUESDAY. THE TUESDAY SYSTEM IS EXPECTED TO
MOVE THROUGH PRETTY QUICKLY...WHICH WILL HELP MITIGATE HYDRO
PROBLEMS. HOWEVER...RAINFALL COULD BE HEAVY FOR A SHORT TIME ON
TUESDAY AND WITH SATURATED SOILS EVEN SHORT-DURATION HEAVY RAIN
EVENTS CAN RESULT IN AT LEAST MINOR HYDRO PROBLEMS. IN
ADDITION...WINDS WITH THE TUESDAY SYSTEM ARE EXPECTED TO BE
SOMEWHAT STRONGER THAN THE SUNDAY/SUNDAY NIGHT SYSTEM. BUT THE
LATEST WRF WIND FORECAST HAS BACKED OFF ON WINDS ON TUESDAY AND
SO THERE MAY NOT BE A NEED FOR WIND ADVISORIES WITH THIS SECOND
SYSTEM EITHER.
MOST OF OUR FORECAST AREA SHOULD GET A CHANCE TO DRY OUT A BIT
AROUND MIDWEEK AS A SHORTWAVE RIDGE BUILDS OVER CA TEMPORARILY.
BUT ANOTHER ROUND OF RAINFALL IS LIKELY BY LATE IN THE WEEK. THE
TIMING OF THE LATE-WEEK SYSTEM IS SOMEWHAT UNCERTAIN AS WOULD BE
EXPECTED WITH AN ACTIVE WEATHER PATTERN SEVERAL DAYS IN ADVANCE.
BUT INDICATIONS ARE THAT FRIDAY WILL LIKELY BE WET...WITH YET MORE
RAIN POSSIBLE NEXT WEEKEND.
&&
.AVIATION...AS OF 9:30 AM PST SUNDAY...MAIN FOCUS FOR THE 18Z
PACKAGE WAS FOR TIMING OF THE RAIN AS A FRONT MOVES THROUGH OUR
AREA TODAY AND TONIGHT. LAST THREE RUNS OF THE HRRR HAVE ONLY
SLIGHTLY CHANGED, SO CONFIDENCE IN THE TIMING LISTED IN THE TAF IS
FAIRLY HIGH. WINDS ALSO ON TRACK TO INCREASE AS THE FRONT NEARS.
RAIN ENDS NEAR THE END OR JUST OUTSIDE OF THE TAF PACKAGE.
MODERATE TO HIGH CONFIDENCE FOR TIMING. MODERATE CONFIDENCE ON
VIS AND CIG HEIGHTS.
VICINITY OF KSFO...MVFR CIGS FORECAST THROUGH MOST OF THE PERIOD.
-RA RETURN AROUND 23Z OR 0Z WITH POTENTIAL FOR RA OR EVEN +RA AT
OR A BIT AFTER 04Z. WINDS OF 170 TO 190 AROUND 10 KT. SPEEDS WILL
INCREASE WITH GUSTS OVER 20 KT POSSIBLE AFTER 23Z. MODERATE TO
HIGH CONFIDENCE.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MOSTLY MVFR VFR CONDITIONS THROUGH
THE DAY WITH -RA EXPECTED AFTER 04Z. WINDS GENERALLY 170 TO 190 AT
KMRY TO 10 KT. AT KSNS WINDS OF 130 TO 150 FORECAST WITH GUSTS
OVER 20 KT AFTER 02Z. MODERATE CONFIDENCE.
&&
.BEACHES...AS OF 10:00 AM PST SUNDAY... AN APPROACHING LONG PERIOD
WEST SWELL WILL BRING HAZARDOUS CONDITIONS TO REGIONAL BEACHES
THROUGH MONDAY. WEST SWELLS WILL STEADILY INCREASE TO 16 TO 19 FEET
WITH A PERIOD OF 17 TO 19 SECONDS TODAY. EXTREME WAVE RUN UP IS
EXPECTED WITH THIS SWELL AS LONG LULLS IN BETWEEN WAVE SETS WILL
INCREASE RISK OF DEADLY RIP CURRENTS...LARGE SNEAKER WAVES... AND
THE LIKELIHOOD OF BEING WASHED INTO SEA BY A WAVE. SMALL VESSELS
ALONG THE IMMEDIATE COAST MAY ALSO BE PUSHED INTO COASTAL ROCKS.
DURING HIGH TIDE... COASTAL INUNDATION MAY CUT OFF ACCESS TO SOME
BEACHES AND OUTCROPPINGS. THE LARGE WAVES WILL GRADUALLY TAPER OFF
EARLY NEXT WEEK.
&&
.MARINE...AS OF 08:33 AM PST SUNDAY...LOOK FOR INCREASING
SOUTHERLY WINDS TODAY AS A SYSTEM MOVES THROUGH. THE STRONGEST
WINDS WILL BE OVER THE NORTHERN WATERS. WINDS WILL DECREASE
TONIGHT AFTER THE FRONT PASSES BUT ANOTHER SYSTEM WILL INCREASE
THE WINDS AGAIN TUESDAY. A LARGE SWELL TRAIN GENERATED BY THESE
SERIES OF STORMS WILL AFFECT THE WATERS THROUGH AT LEAST MONDAY
MORNING.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...COASTAL FLOOD WARNING...ALL COASTAL ZONES AS WELL AS NORTH
BAY ZONES BORDERING SF BAY.
HIGH SURF WARNING...ALL COASTAL ZONES FROM SONOMA TO
MONTEREY COUNTY.
FLASH FLOOD WATCH...NORTH BAY COUNTIES OF SONOMA...NAPA
AND MARIN.
SCA...PIGEON PT TO PT PINOS 0-10 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PT REYES TO PIGEON PT 0-10 NM
SCA...PT ARENA TO PIGEON PT 10-60 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: MM
AVIATION: BELL
MARINE: BELL
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
909 AM PST SUN JAN 17 2016
.SYNOPSIS...A STRONG STORM SYSTEM WILL SPREAD RAIN ACROSS THE
REGION TODAY THROUGH MONDAY MORNING. A PERIOD OF HEAVY RAIN IS
LIKELY...BEGINNING IN THE NORTH BAY THIS AFTERNOON AND ACROSS
THE REMAINDER OF THE FORECAST AREA TONIGHT AND EARLY MONDAY. A
SECOND STORM WILL PRODUCE MORE RAINFALL AND LOCALLY STRONG WINDS
LATE MONDAY NIGHT THROUGH TUESDAY. THERE MAY BE A BRIEF PERIOD OF
DRY WEATHER AROUND THE MIDDLE OF THE WEEK BEFORE ANOTHER STORM
SYSTEM ARRIVES LATE IN THE WEEK.
&&
.DISCUSSION...AS OF 09:06 AM PST SUNDAY...SHORT TERM CONCERNS
WILL CONTINUE TO FOCUS ON THE APPROACHING COLD FRONT AND VERY
ROBUST MOISTURE PLUME CURRENTLY POINTED NORCAL. OVERNIGHT THE RAIN
BUCKETS IN THE NORTH BAY HAVE BEEN STEADILY TIPPING WITH VENADO
WELL OVER AN INCH WITH MANY OTHER LOCATIONS IN THE 0.25 TO 0.5
INCH RANGE. THE LATEST KMUX RADAR IMAGERY MAY NOT BE OVERLY
IMPRESSIVE FOR THE NORTH BAY...BUT RAIN IS STILL BEING REPORTED.
THERE HAVE ALSO BEEN A FEW REPORTS OF MEASURABLE RAIN OVER
PORTIONS OF CONTRA COSTA COUNTY.
FOR THE REST OF TODAY...THE COLD FRONT WILL CONTINUE TO SLOWLY
MOVE SOUTHWARD. THE LATEST HRRR ACTUALLY HANDLES THIS FAIRLY WELL
WITH THE BULK OF THE PRECIP NOT ARRIVING UNTIL LATER THIS
AFTERNOON. DID A QUICK UPDATE TO THE FORECAST TO SLOW DOWN THE
ONSET OF THE HEAVIER PRECIP TODAY AND TO LOWER RAINFALL AMOUNTS
THIS MORNING. FOR MORE SPECIFIC DETAILS ON THE WEATHER SYSTEM SEE
BELOW.
&&
.PREV DISCUSSION...AS OF 3:30 AM PST SUNDAY...EARLY MORNING IR
SATELLITE IMAGERY SHOWS A FRONTAL BOUNDARY EXTENDING FROM THE FAR
NORTHERN CALIFORNIA COAST WSW OVER THE PACIFIC. THE MOISTURE PLUME
COINCIDENT WITH THIS BOUNDARY CONTAINS PRECIPITABLE WATER VALUES
EXCEEDING 1.5 INCHES WITH A MAXIMUM OF 2 INCHES. A STRONG
SHORTWAVE TROUGH CURRENTLY RIDING ALONG THE FRONTAL BOUNDARY HAS
RESULTED IN STRONG ENHANCEMENT OF THE FRONT JUST OFF THE NORTHERN
CA COAST NORTH OF CAPE MENDOCINO...WITH EMBEDDED CONVECTION AND
NUMEROUS LIGHTNING STRIKES IN THAT AREA. THE MODELS HAVE BEEN
CONSISTENT IN GRADUALLY SLIDING THE FRONTAL BOUNDARY AND
ASSOCIATED ENHANCED RAINFALL SOUTH THROUGH OUR FORECAST AREA LATER
TODAY AND TONIGHT. THE LATEST MODELS HAVE DELAYED THE ONSET OF
HEAVIEST RAINFALL A BIT. BASED ON A CONSENSUS OF THE MODELS...THE
HEAVIEST RAINFALL IN THE NORTH BAY IS EXPECTED FROM EARLY THIS
AFTERNOON THROUGH EARLY EVENING...THEN FROM EARLY EVENING THROUGH
LATE TONIGHT FOR THE REST OF THE SF BAY AREA AND SANTA CRUZ
COUNTY...AND FROM ABOUT MIDNIGHT THROUGH SUNRISE MONDAY MORNING
FOR MONTEREY AND SAN BENITO COUNTIES. RAIN RATES ARE EXPECTED TO
BE HEAVY FOR A FEW HOURS WHILE THE FRONTAL BOUNDARY MOVES THROUGH.
THE MAIN CONCERN IS WHETHER THE BAND OF HEAVY RAIN WILL SLOW
SIGNIFICANTLY OR STALL IN ONE PARTICULAR AREA. THE 00Z NAM
INDICATED A WAVE WOULD DEVELOP ALONG THE FRONT EARLY THIS EVENING
AND MAINTAIN HEAVY RAIN RATES IN THE NORTH BAY FOR A MORE
PROLONGED PERIOD OF TIME. THE 06Z NAM DELAYS THE DEVELOPMENT OF
THIS FRONTAL WAVE AND INSTEAD STALLS THE BAND OF HEAVIER RAIN
ACROSS SANTA CRUZ COUNTY AND THE SOUTH BAY OVERNIGHT. ON THE OTHER
HAND...BOTH THE GFS AND ECMWF MOVE THE FRONTAL BOUNDARY THROUGH
OUR ENTIRE AREA AT A STEADY PACE. IN ANY CASE...ALL OF THE MODELS
INDICATE THAT THE GREATEST RAINFALL TOTALS THROUGH MIDDAY MONDAY
WILL BE ACROSS THE NORTH BAY. WILL THEREFORE CONTINUE WITH A FLASH
FLOOD WATCH FOR SONOMA...NAPA AND MARIN COUNTIES THROUGH LATE
TONIGHT.
FOR AREAS SOUTH OF THE GOLDEN GATE....AT LEAST MINOR HYDRO ISSUES
ARE LIKELY TONIGHT...ESPECIALLY IN THE SANTA CRUZ MOUNTAINS AND
SOUTH BAY IF THE 06Z NAM WERE TO VERIFY. WILL CONTINUE TO
HIGHLIGHT THE POSSIBILITY OF MINOR URBAN AND/OR SMALL STREAM
FLOODING WITH A HAZARDOUS WEATHER OUTLOOK FOR ALL AREAS NOT
INCLUDED IN THE FLASH FLOOD WATCH. IN ADDITION...A COMBINATION OF
LARGE POWERFUL OCEAN SWELL AND HEAVY RAINFALL RUNOFF WILL LIKELY
PRODUCE AT LEAST MINOR COASTAL FLOODING...PARTICULARLY AROUND THE
TIMES OF HIGH TIDE NEAR 6 PM THIS EVENING AND THEN AGAIN AROUND 6
AM ON MONDAY MORNING. A COASTAL FLOOD WARNING IS IN EFFECT FROM 4
PM TODAY UNTIL 7 AM MONDAY FOR ALL COASTAL ZONES AS WELL AS AREAS
AROUND THE NORTHERN SAN FRANCISCO BAY...PARTICULARLY BAYSIDE
LOCATIONS OF MARIN COUNTY.
WINDS WITH THIS SYSTEM ARE NOT EXPECTED TO REACH ADVISORY LEVELS.
THERE WILL BE MODERATELY STRONG AND GUSTY SOUTHERLY WINDS NEAR THE
COAST AND LOCALLY IN THE HILLS FROM THIS AFTERNOON THROUGH
TONIGHT...WHEN WIND GUSTS UP TO 35 MPH ARE POSSIBLE.
INDICATIONS ARE THAT RAINFALL WILL TAPER OFF PRETTY QUICKLY ON
MONDAY MORNING AND MOSTLY END BY MONDAY AFTERNOON. THERE WILL BE
ONLY A SHORT BREAK IN THE ACTION BEFORE THE NEXT SYSTEM SWEEPS IN
LATE MONDAY NIGHT AND TUESDAY. THE TUESDAY SYSTEM IS EXPECTED TO
MOVE THROUGH PRETTY QUICKLY...WHICH WILL HELP MITIGATE HYDRO
PROBLEMS. HOWEVER...RAINFALL COULD BE HEAVY FOR A SHORT TIME ON
TUESDAY AND WITH SATURATED SOILS EVEN SHORT-DURATION HEAVY RAIN
EVENTS CAN RESULT IN AT LEAST MINOR HYDRO PROBLEMS. IN
ADDITION...WINDS WITH THE TUESDAY SYSTEM ARE EXPECTED TO BE
SOMEWHAT STRONGER THAN THE SUNDAY/SUNDAY NIGHT SYSTEM. BUT THE
LATEST WRF WIND FORECAST HAS BACKED OFF ON WINDS ON TUESDAY AND
SO THERE MAY NOT BE A NEED FOR WIND ADVISORIES WITH THIS SECOND
SYSTEM EITHER.
MOST OF OUR FORECAST AREA SHOULD GET A CHANCE TO DRY OUT A BIT
AROUND MIDWEEK AS A SHORTWAVE RIDGE BUILDS OVER CA TEMPORARILY.
BUT ANOTHER ROUND OF RAINFALL IS LIKELY BY LATE IN THE WEEK. THE
TIMING OF THE LATE-WEEK SYSTEM IS SOMEWHAT UNCERTAIN AS WOULD BE
EXPECTED WITH AN ACTIVE WEATHER PATTERN SEVERAL DAYS IN ADVANCE.
BUT INDICATIONS ARE THAT FRIDAY WILL LIKELY BE WET...WITH YET MORE
RAIN POSSIBLE NEXT WEEKEND.
&&
.AVIATION...AS OF 5:30 AM PST SUNDAY...LATEST GOES IMAGE SHOWS
LOW CIGS WITH LOCAL DRIZZLE OR LIGHT RAIN EXTENDS FROM THE SAN
MATEO COAST INTO THE NORTH BAY. TRICKY FORECAST TODAY AS SFO IS
RIGHT ON THE EDGE OF THE CLOUD DECK. COULD SEE SOME MVFR CIGS INTO
SFO FROM TIME TO TIME THIS MORNING. CHANCES FOR MVFR CIGS INCREASE
IN THE AFTERNOON AS THE FRONTAL SYSTEM APPROACHES. SOUTHEAST WINDS
WILL INCREASE BY THIS EVENING AS THE FRONT IS THEN FORECAST TO
PROGRESS SOUTH.
VICINITY OF KSFO...A MIX OF VFR AND MVFR CIGS THIS MORNING.
MVFR CIGS BECOMES MORE LIKELY AFTER 16Z. SOUTHEAST WINDS
REMAINING LIGHT AROUND 5 KT INCREASING TO 10 KT AFTER 17Z AND
15-20 KT AFTER 23Z.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...LIFR FOR CIGS AND VIS THROUGH 16Z.
IMPROVING TO MVFR AFTER 17Z AND VFR AFTER 19Z AS FOG CLEARS OUT.
&&
.BEACHES...AS OF 4:00 AM PST SUNDAY... AN APPROACHING LONG PERIOD
WEST SWELL WILL BRING HAZARDOUS CONDITIONS TO REGIONAL BEACHES
THROUGH MONDAY. WEST SWELLS WILL STEADILY INCREASE TO 16 TO 19 FEET
WITH A PERIOD OF 17 TO 19 SECONDS TODAY. EXTREME WAVE RUN UP IS
EXPECTED WITH THIS SWELL AS LONG LULLS IN BETWEEN WAVE SETS WILL
INCREASE RISK OF DEADLY RIP CURRENTS...LARGE SNEAKER WAVES... AND
THE LIKELIHOOD OF BEING WASHED INTO SEA BY A WAVE. SMALL VESSELS
ALONG THE IMMEDIATE COAST MAY ALSO BE PUSHED INTO COASTAL ROCKS.
DURING HIGH TIDE... COASTAL INUNDATION MAY CUT OFF ACCESS TO SOME
BEACHES AND OUTCROPPINGS. THE LARGE WAVES WILL GRADUALLY TAPER OFF
EARLY NEXT WEEK.
&&
.MARINE...AS OF 08:33 AM PST SUNDAY...LOOK FOR INCREASING
SOUTHERLY WINDS TODAY AS A SYSTEM MOVES THROUGH. THE STRONGEST
WINDS WILL BE OVER THE NORTHERN WATERS. WINDS WILL DECREASE
TONIGHT AFTER THE FRONT PASSES BUT ANOTHER SYSTEM WILL INCREASE
THE WINDS AGAIN TUESDAY. A LARGE SWELL TRAIN GENERATED BY THESE
SERIES OF STORMS WILL AFFECT THE WATERS THROUGH AT LEAST MONDAY
MORNING.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...COASTAL FLOOD WARNING...ALL COASTAL ZONES AS WELL AS
NORTH BAY ZONES BORDERING SF BAY.
HIGH SURF WARNING...THE COAST FROM SONOMA COUNTY
SOUTH TO MONTEREY COUNTY.
FLASH FLOOD WATCH...NORTH BAY COUNTIES OF SONOMA...
NAPA AND MARIN
SCA...PIGEON PT TO PT PINOS 0-10 NM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
SCA...PT ARENA TO PT REYES 0-10 NM
SCA...PT REYES TO PIGEON PT 0-10 NM
SCA...PT ARENA TO PIGEON PT 10-60 NM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM
SCA...ROUGH BAR ADVISORY FOR SF BAR
&&
$$
PUBLIC FORECAST: MM
AVIATION: W PI
MARINE: BELL
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 PUEBLO CO
1034 AM MST SUN JAN 17 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 423 AM MST SUN JAN 17 2016
...SNOW AND WIND CONTINUES FOR THE CENTRAL MOUNTAINS TODAY...
NEXT UPPER WAVE IS CURRENTLY MOVING INTO NW CO...AND WILL CONTINUE
TO DROP SOUTHEASTWARD INTO THE TX PANHANDLE BY MID DAY. AREA RADARS
SHOWING PERSISTENT SNOW BANKED UP INTO THE NORTHWEST FACING SLOPES
OF CHAFFEE AND LAKE COUNTY...WITH LXV REPORTING A FEW HUNDREDTHS OF
PRECIPITATION EACH HOUR. LIKELY SOME PRETTY STOUT WINDS ACROSS THE
HIGHER ELEVATIONS...AS KCCU AND K7BM ARE REPORTING GUSTS 30-35
KTS...AND IT IS LIKELY THAT GUSTS AT PEAK LEVEL ARE PROBABLY AROUND
50 KTS OR BETTER BASED ON MODEL SOUNDINGS. FREMONT PASS WEBCAM HAS
BEEN SHOWING POOR VISIBILITIES AT TIMES WITH SNOW AND BLOWING SNOW.
LATEST HIGH RES MODELS HAVE COME IN HEAVIER WITH SNOWFALL ACROSS THE
HIGHER ELEVATIONS OF THE SAWATCH AND MOSQUITO RANGES WHICH JIVES
WELL WITH ABOVE OBSERVATIONS...AND HAVE ALREADY HOISTED A WINTER
WEATHER ADVISORY FOR ZONE 58 AND 60 THROUGH TODAY. HEAVIEST SNOW
WILL FALL THIS MORNING ASSOCIATED WITH THE BETTER FORCING/CAA. THEN
PERSISTENT NORTHWEST FLOW WILL PROVIDE FAVORABLE OROGRAPHICS FOR
SNOW SHOWERS TO CONTINUE THROUGH THE AFTERNOON...THOUGH AT LESSER
RATES. THAT COMBINED WITH THE PROBABILITY FOR BLOWING SNOW TO
CONTINUE...THE WINTER WEATHER ADVISORY WILL CARRY THROUGH 5 PM THIS
EVENING.
ALSO WATCHING THE ARCTIC COLD FRONT PUSH INTO EASTERN PORTIONS OF
THE PLAINS EARLY THIS MORNING WITH STRATUS AND TEMPERATURES IN THE
TEENS PUSHING SOUTHWESTWARD. LATEST HRRR BACKS THIS AIRMASS WESTWARD
INTO THE SOUTHEAST PLAINS THROUGH THE MORNING WITH POTENTIAL FOR
STRATUS TO SPREAD AS FAR WEST AS KLHX. COULD EVEN SEE SOME LOW
CLOUDS BRIEFLY FORM AT KPUB BY LATE MORNING...BUT ASSUMING MODELS
ARE HANDLING THE WESTWARD PUSH OF THE COLDER AIR...DON`T THINK
CLOUDS WILL BECOME PERSISTENT AT KPUB. THIS WILL POSE CHALLENGES FOR
MAX TEMPS TODAY THOUGH...AS NORTHWEST WINDS AND SLIGHTLY WARMER
TEMPERATURES ACROSS THE MTS AND LOWER EASTERN SLOPES WILL TRANSITION
INTO THE COLDER AIRMASS BANKED INTO THE SOUTHEAST PLAINS. GETTING
THIS GRADIENT IN THE CORRECT POSITION WILL BE KEY TO FORECASTING MAX
TEMPERATURES TODAY...AND WITH EASTERLY SFC WINDS EXPECTED AT
KPUB...KEPT TEMPERATURES BELOW GUIDANCE FOR THE LOWER ARKANSAS RIVER
VALLEY FROM KPUB EASTWARD. WOULDN`T BE SURPRISED TO SEE HIGHS ONLY
IN THE 20S ALONG THE KS BORDER THIS AFTERNOON. HAVE ALSO INCLUDED
SOME FOG IN THE GRIDS FOR THE FAR EASTERN PLAINS...AND WILL HAVE TO
WATCH FOR THE POTENTIAL FOR IT TO BECOME DENSE...OR EVEN PRODUCE
SOME SPOTTY FREEZING DRIZZLE LATER THIS MORNING AS LOWER ATMOS
SATURATES. ANY VIS RESTRICTIONS SHOULD BREAK BY NOON...AND MODELS
SUGGEST STRATUS WILL BREAK UP DURING THE MID AFTERNOON FOR FAR
EASTERN AREAS.
TONIGHT...LEE TROF KICKS EASTWARD AND ARCTIC AIRMASS RECEDES
EASTWARD ACROSS THE PLAINS. SHOULD BE A QUICK DROP IN TEMPERATURES
THIS EVENING THOUGH...ESPECIALLY FOR THE EASTERN PLAINS.
MEANWHILE...WESTERLY WINDS ACROSS THE MTS/I-25 CORRIDOR SHOULD KEEP
MIN TEMPS IN THE MID-UPPER 20S IN THE USUAL BREEZY SPOTS LIKE CANON
CITY AND WALSENBURG. TRICKY FORECAST AGAIN FOR KALS. GUIDANCE HAS
BEEN PERSISTENTLY UNDERDOING THE AMOUNT OF RADIATIONAL COOLING AT
NIGHT OVERTOP SNOWPACK ACROSS THE SAN LUIS VALLEY...ESPECIALLY IF
CLOUDS ARE LACKING. THERE WILL BE ANOTHER BOUT OF HIGH CLOUDS
SPILLING IN OVERTOP THE UPPER RIDGE AXIS TONIGHT...BUT APPEARS THAT
BETTER MOISTURE WILL STAY OFF TO THE NORTH AND WEST...SO HAVE
UNDERCUT GUIDANCE FOR MIN TEMPS FOR THE SAN LUIS VALLEY AGAIN
TONIGHT. WILL HAVE TO WATCH FOR THE EVER PRESENT THREAT FOR PATCHY
DENSE FOG ACROSS THE SAN LUIS VALLEY TONIGHT AS WELL. -KT
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 423 AM MST SUN JAN 17 2016
...SEVERAL DISTURBANCES TO BRING SNOW TO THE MOUNTAINS...
MONDAY THROUGH WEDNESDAY...MODELS HAVE BEEN VERY CONSISTENT IN
KEEPING AN ACTIVE UPPER PATTERN IN PLACE FOR THE REGION...AND
ESPECIALLY FOR THE HIGHER ELEVATIONS WITH A FOCUS ON THE CONTDVD. ONE
DISTURBANCE WILL CROSS MONDAY NIGHT INTO TUESDAY...AND THE SECOND
WILL CROSS ON WEDNESDAY. GIVEN THE GENERAL NW FLOW ALOFT...THE
CONTDVD WILL RECEIVE THE BRUNT OF THE NEW SNOWFALL...AND
PARTICULARLY THE CENTRAL MTS. EACH EVENT SHOULD BRING 1 TO 3 INCHES
OF NEW SNOW TO THE HIGHER TERRAIN OF LAKE AND CHAFFEE COUNTIES...AND
UP TO 2 INCHES FOR THE REMAINING MTS. MAX TEMPS EACH DAY ARE
EXPECTED TO CLIMB TO NEAR 50 F FOR THE PLAINS...AND INTO THE 30S TO
NEAR 40 F FOR THE HIGH VALLEYS.
THURSDAY THROUGH SATURDAY...A RIDGE OF HIGH PRESSURE BUILDS ACROSS
THE SOUTHWESTERN US...ALLOWING FOR DRY CONDITIONS ACROSS THE CWA FOR
THU AND FRI. MAX TEMPS ON THU SHOULD BE THE SAME AS EARLIER IN THE
WEEK...BUT FOR FRI AND SAT WILL WARM TO NEAR 60 F FOR THE
PLAINS...AND INTO THE MID 30S TO MID 40S FOR THE HIGH VALLEYS.
LATEST MODEL RUNS HINT AT ANOTHER UPPER WAVE CROSSING THE REGION FOR
SAT...BRINGING ISOLATED SNOW TO THE CONTDVD. HOWEVER...AT THIS TIME
THIS FEATURE LOOKS TO BE MORE OF A GLANCING BLOW TO THE
NORTH...WHICH WOULD KEEP SNOW AMOUNTS LIGHT WITH LITTLE EFFECT ON
TEMPS EAST OF THE MTS. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1024 AM MST SUN JAN 17 2016
AT KALS...VFR TODAY THEN IFR AFTER 10Z TONIGHT AS HIGH LEVEL
CLOUDINESS CLEARS...ALLOWING LOW CLOUDS AND PATCHY GROUND FOG TO
FORM NEAR THE RIO GRANDE. CONDITIONS THEN GRADUALLY IMPROVE BACK
TO VFR BY MIDDAY MON.
AT KCOS...VFR TODAY AND TONIGHT AS LOWER CLOUDS STAY EAST OF THE
TERMINAL.
AT KPUB...IFR STRATUS JUST EAST OF THE TERMINAL AT 17Z...BUT
WESTWARD EXPANSION OF THE LOW CLOUD DECK HAS JUST ABOUT
ENDED...WITH SOME EROSION FROM THE NORTH OCCURING AS WELL. WILL
THUS KEEP IFR CIGS OUT OF THE TAF AT THIS POINT...THOUGH IT WILL
BE A CLOSE CALL. VFR CONDITIONS THEN EXPECTED FOR THE REMAINDER OF
THE DAY AND OVERNIGHT.
OVER THE MOUNTAINS...STILL A FEW MOURE HOURS OF PATCHY IFR/LIFR
CONDITIONS IN SNOW AND BLOWING SNOW OVER THE CENTRAL MOUNTAINS
NORTH OF KMYP THIS AFTERNOON...THEN GRADUAL IMPROVEMENT OVERNIGHT
INTO MONDAY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR COZ058-
060.
&&
$$
SHORT TERM...KT
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS WICHITA KS
339 PM CST SUN JAN 17 2016
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 335 PM CST SUN JAN 17 2016
ELONGATED BAND OF -SHSN PERSISTING ACROSS FORECAST AREA LATE THIS
AFTERNOON...DUE TO PERSISTENT...MOIST...ISENTROPIC UPGLIDE 285-290K
THETA SURFACES...ENHANCED BY WEAK JET STREAK APPARENT IN WATER VAPOR
IMAGERY. 06UTC NAM PROVIDED SOME HINT...AND 17UTC RAP APPEARS TO BE
BEST PREDICTIVE VALUE AT PRESENT. EXPECT POTENTIAL FOR SNOW SHOWERS
TO DIMINISH BY EARLY TO MID-EVENING.
AFTER SNOW CHANCES DIMINISH...MAY FORECAST CONCERN WILL BE OVERNIGHT
TEMPERATURES. CLOUD COVER WILL PERSIST MOST OF THE NIGHT...WHICH
WILL HELP COUNTER RADIATIVE AND ADVECTION COOLING. DUE TO SNOW PACK
ACROSS NORTHEAST KANSAS...TRENDED SLIGHTLY COLDER THAN GUIDANCE
FLINT HILLS INTO NORTH CENTRAL KANSAS DUE TO ADVECTIVE PROCESSES.
TEMPERATURES WILL BE ABLE TO REBOUND ABOVE FREEZING CENTRAL AND
SOUTH CENTRAL KANSAS ON MONDAY...DUE TO RETURN SOUTHERLY FLOW.
SOUTHEAST AND NORTHEAST KANSAS WILL REMAIN UNDER GRIP OF
DEEPER...COLDER AIRMASS...THUS MAX TEMPS ONLY EXPECTED TO REACH MID
TO UPPER 20S. TEMPERATURES MONDAY INTO TUESDAY WILL MODERATE DUE TO
SOUTHERLY FLOW...BUT THEN ANOTHER FAST MOVING SYSTEM WILL DIVE
ACROSS THE PLAINS BRINGING ANOTHER SHOT OF COLDER AIR AND POSSIBLY A
CHANCE OF LIGHT SNOW OR RAIN/SNOW MIX TUESDAY AFTERNOON AND TUESDAY
NIGHT.
ANOTHER FAST MOVING SHORT WAVE DIVES INTO SOUTHERN PLAINS WEDNESDAY
NIGHT INTO TUESDAY. FORECAST MODELS DEEPENED/INTENSIFIED THIS OPEN
WAVE THE PAST FEW RUNS. DETERMINISTIC MODELS ARE SHOWING
VARIABILITY IN TRACK AND DEPTH OF H5/SURFACE LOW...WHICH WILL HAVE
IMPACT ON PRECIPITATION TYPE. GFS IS MORE BULLISH WITH PRECIPITATION
AND EVOLVES WARM AND MOIST CONVEYOR BELT MORE SO THAN ECWMF. GFS
ENSEMBLES ALL OVER THE PLACE WITH H5 EVOLUTION AND EC MEAN ENSEMBLE
LOOKS RATHER ANEMIC. GIVEN UNCERTAINTY...KEPT PRECIPITATION CHANCES
ON THE LOW SIDE AND DID NOT GET TOO SPECIFIC WITH PRECIPITATION
TYPE.
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 335 PM CST SUN JAN 17 2016
EXTENDED PART OF THE FORECAST PERIOD INDICATES A WARMING AND DRY
TREND AS H5 RIDGING BUILDS OVER INTERMOUNTAIN WEST FRIDAY AND
SATURDAY.
SF
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1129 AM CST SUN JAN 17 2016
LOW CLOUDS WILL CONTINUE TO PUSH SOUTHWARD INTO OKLAHOMA
TODAY...AS DRIER LOW LEVEL AIR SPREADS ACROSS THE REGION. MID
LEVEL CLOUDS WILL LINGER ACROSS THE AREA INTO TONIGHT WITH VFR
CONDITIONS EXPECTED.
JAKUB
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 9 31 23 38 / 30 0 0 30
HUTCHINSON 8 32 24 34 / 30 0 0 30
NEWTON 6 30 22 34 / 50 0 0 30
ELDORADO 10 28 22 37 / 50 0 0 40
WINFIELD-KWLD 9 31 23 42 / 20 0 0 30
RUSSELL 8 35 23 32 / 20 0 10 30
GREAT BEND 8 36 24 33 / 20 0 10 20
SALINA 6 31 22 31 / 30 0 10 40
MCPHERSON 8 31 23 33 / 50 0 10 30
COFFEYVILLE 10 29 23 45 / 30 10 0 40
CHANUTE 6 27 20 42 / 40 0 10 40
IOLA 5 26 20 41 / 30 0 0 50
PARSONS-KPPF 6 28 21 43 / 30 0 0 40
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
332 PM CST SUN JAN 17 2016
.SHORT TERM...(THIS EVENING THROUGH Monday)
ISSUED AT 328 PM CST SUN JAN 17 2016
In the short term the forecast will revolve around temperature
trends, as well as clouds and any flurried or fog. The HRRR seemed
to have a better trend for hourly temperatures this afternoon
and was generally followed. The surface high will become
reinforced across the northern plains and extending into the
southern plains. Temperatures will likely be as cold or colder
tonight, albeit without the wind that was present Sunday morning.
Again freezing fog canbe an issue again early Monday morning,
reducing visibility in some areas. A quick return to southerly
surface winds and increase in insolation by midday Monday, aiding
to a bump in temperatures wellabove freezing on the higher
elevation western counties. Cold highs in the low 30s are all
that can be expected on the lower plains(Hays to medicine Lodge).
.LONG TERM...(Monday NIGHT THROUGH Sunday)
ISSUED AT 328 PM CST SUN JAN 17 2016
Models indicate a shortwave moving through the central plains
aroundTuesday, which is somewhat weak and moisture starved. Any
snow mightbe minimal with this fast moving feature. A reasonable
moderation inmorning lows is likely by this time as the very cold
air associatedwith the surface high should be moving east of the
region. Asimilar, 2nd wave is possible about 48 hours later, with
aalight chance for snow once again.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Monday AFTERNOON)
ISSUED AT 1223 PM CST SUN JAN 17 2016
Cold surface high pressure will become reinforced from the Northern
Plains to the Missouri valley. Northeast surface winds will perisist
as a result. Widespread stratus will continue to result due to the
upslope flow pattern, with ceilings improving through the
afternoon, but likley deteriorating once again this evening and
overnight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 11 41 26 41 / 0 0 10 10
GCK 12 47 25 44 / 0 0 10 10
EHA 16 54 29 49 / 0 0 0 10
LBL 14 48 28 47 / 0 0 10 10
HYS 7 34 23 37 / 10 0 10 10
P28 9 34 27 39 / 0 0 10 10
&&
.DDC Watches/Warnings/Advisories...NONE.
&&
$$
SHORT TERM...Russell
LONG TERM...Russell
AVIATION...Russell
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
409 PM EST SUN JAN 17 2016
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 408 PM EST SUN JAN 17 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A COLD MID/UPPER LEVEL LOW
JUST TO THE EAST OF LAKE SUPERIOR. AT THE SFC...NW LOW LEVEL FLOW
PREVAILED BTWN A RIDGE OVER THE PLAINS AND A TROUGH FROM JAMES BAY
TO SRN ONTARIO. RADAR AND VIS LOOP SHOWED MAINLY MULTI-BAND LES WITH
FEW DOMINANT OR COHERENT BANDSAS THE LES INTENSITY HAS DIMINISHED
SLIGHTLY WITH THE VERY DRY ARCTIC AIR UPSTREAM AND THE LAKES
AGGREGATE TROUGH SHIFTING TO THE SOUTH OF UPPER MICHIGAN.
INSTABILITIY OVER THE LAKE REMAINED HIGH WITH 850/700 MB TEMPS
AROUND -23C/-30C RESULTING IN LAKE INDUCED CAPES NEAR 1K J/KG AND
EQUILLIBRIUM HEIGHTS TO 14K FT.
TONIGHT...EXPECT MODERATE TO OCASSIONALLY HEAV LES TO CONTINUE FOR
NW FLOW FAVORED LOCATIONS. THE HIGH RES MODELS SUGGEST THAT THE MOST
FAVORALBE LOW LEVEL CONV OVER THE WEST WILL FOCUS INTO ONTONAGAON
COUNTY THIS EVENING. OVER THE EAST...MORE DOMINANT BANDS COULD OVER
A WIDER AREA FROM FROM ALGER COUNTY INTO LUCE COUNTY. LES INTENSITY
SHOULD ALSO INCREASE WITH A SHRTWV OVER NRN ONTARIO ROTATING TO NEAR
ERN LAKE SUPERIOR BY 12Z. HOWEVER...WINDS WILL ALSO BACK SLIGHTLY IN
RESPONSE TO THE INCOMING SHRTWV. ALTHOUGH SNOWFALL AMOUNTS MAY NOT
BE AS HEAVY AS LAST NIGHT...5 TO 9 INCH AMOUNTS WILL BE POSSIBLE
OVER THE EAST. THE SHORTER FETCH AND SLIGHTLY LOWER INVERSION
HEIGHTS OVER THE WEST SHOULD KEEP AMOUNTS IN THE 2 TO 5 INCH RANGE.
ENOUGH OF THE CONVECTIVE LAYER WILL REACH INTO THE DGZ TO KEEP SLR
VALUES AOA 25/1.
THE VERY COLD AIR MOVING INTO INTERIOR LOCATIONS WILL DROP WIND
CHILLS INTO THE -20 TO -30 RANGE NEAR THE WI BORDER FROM IRONWOOD TO
CRYSTAL FALLS TONIGHT WHERE A WIND CHILL ADVY REMAINS IN EFFECT.
EXPECT ENOUGH LAKE MODERATION FARTHER NORTH FOR WIND CHILLS MAINLY
IN THE -10 TO -20 RANGE.
MONDAY...AS THE SHRTWV MOVES IN WITH THE STRONGER FORCING SHIFTING
TO THE SOUTH...WINDS WILL GRADUALY VEER. CONDITIONS WILL REMAIN
FAVORABLE FOR MODERATE TO HEAVY LES...AGAIN HEAVIEST OVER THE EAST
WITH SLIGHTLY HIGHER INVERSION HEIGHTS AND LONGER FETCH LENGTHS.
WARNINGS AND ADVISORIES WILL REMAIN IN EFFECT THROUGH THE DAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 547 AM EST SUN JAN 17 2016
...LAKE EFFECT SNOW GRADUALLY DIMINISHES MON NIGHT INTO TUE...
UPPER TROUGH OVER THE GREAT LAKES MOVES OVER FAR EASTERN CANADA
EARLY THIS WEEK AND OFF ACROSS THE NORTH ATLANTIC BY WED WHILE
AMPLFIED ZONAL FLOW DEVELOPS OVER THE CONUS. COLD AIR WITH H85 TEMPS
DOWN TO -22C ON MON MORNING EASES BY TUE AND WED AS H85 TEMPS RISE TO
-14C BY LATE TUE INTO WED. LAKE INDUCED TROUGHING PERSISTS THROUGH
MONDAY...BUT UNLIKE THIS MORNING WITH MESOLOW ON THE
TROUGH...APPEARS THAT OVERALL RISING HEIGHTS ALOFT WILL RESULT IN
MORE OF A STEADY STATE CONVERGENT NW FLOW ON MONDAY....FOCUSING OVER
ALGER THROUGH LUCE COUNTIES. SOUNDINGS SHOW SLOWLY DIMINISHING
INSTABILITY...BUT STILL LOOKING AT INVERSIONS NEAR 5KFT OVER WESTERN
CWA AND NEAR 10KFT OVER EAST CWA. SHORTWAVE AND DEEP LAYER FORCING
DROPPING ACROSS LK SUPERIOR AND UPR MICHIGAN...ESPECIALLY EAST HALF
WILL CONTINUE TO LEAD TO HEAVY LAKE ENHANCED SNOW WITH SNOW RATES
OVER 1 INCH PER HOUR. BASED ON HOW THIS EVENT HAS WENT THUS FAR
THOUGH WITH TREMENDOUS HOURLY SNOW RATES AIDED IN LARGE PART BY VERY
HIGH SLR/S OVER 30:1...SHOULD SEE RATES 1-3 INCHES PER HOUR IN THE
HEAVIEST SNOW BANDS. BY MON AFTN...LARGER SCALE FORCING BEGINS TO
DIMINISH AS SHORTWAVE EXITS THE AREA AND Q-VECTOR DIVERGENCE MOVES
IN WITH SUBSIDENCE. INVERSIONS BEGIN TO FALL SHARPLY MON EVENING SO
EVEN THOUGH MAJORITY OF MOIST LAKE EFFECT LAYER REMAINS IN THE
DGZ...EXPECT SNOW INTENSITY TO START TAKING BIGGER HIT. AS THE SFC
RIDGE OVER THE NORTHERN PLAINS ATTEMPTS TO MOVE MORE NORTH OF LK
SUPERIOR...SFC-H925 WINDS VEER NNW FM NW SO MAY SEE SNOW SHOWERS
MOVE BACK OVER MORE AREAS NEAR LK SUPERIOR. WITH THE NEGATIVE
FACTORS MENTIONED INTENSITY SHOULD BE COMING DOWN BUT WILL KEEP POPS
HIGH FOR MAINLY LIGHT SNOW AMOUNTS. LATE ON MON NIGHT WINDS BACK
MORE NW AGAIN...SO EXPECT LAKE EFFECT TO RETURN TO NW SNOW BELTS BY
TUE MORNING WHERE IT SHOULD REMAIN UNTIL TUE NIGHT IN DIMINISHED
STATE AS WINDS BECOME OFFSHORE AS SFC RIDGE MOVES ACROSS.
AS FOR QPF/SNOW...SIMILAR TO LAST NIGHT RAMPED UP QPF/SNOW COMPARED
TO CONSENSUS AND WPC. GIVEN QPF WHICH EXCEEDED TWO TENTHS OF AN INCH
IN 6 HOURS WHERE HEAVIER SNOW BANDS WERE EXPECTED ALONG WITH SLR/S
25-30:1 YIELDED A 12 HOUR SNOWFALL OF 3-6 INCHES OVER WESTERN UPR
MICHIGAN ON MON WITH AMOUNTS MORE TOWARD 5-8 INCHES OVER
ALGER/NORTHERN SCHOOLCRAFT AND LUCE COUNTIES AS PERSISTENT HIGH
INSTABILITY LAKE EFFECT SETUP IS MORE AFFECTED DIRECTLY BY SHORTWAVE
DROPPING SOUTH ACROSS THE AREA THROUGH AT LEAST MID AFTN ON MON.
BASED ON THE HIGHER THAN EXPECTED SLR/S OF THIS EVENT THUS FAR WOULD
NOT BE SURPRISED TO SEE HIGHER SLR/S AND THUS HIGHER SNOW
AMOUNTS...AT LEAST LOCALLY. COORD WITH SHORT TERM FORECASTER AND
DECIDED TO PUT WARNINGS UP FOR NORTHERN SCHOOLCRAFT AND LUCE
COUNTIES AND EXTEND WESTERN UPR MICHIGAN WARNING THROUGH MON. ADVYS
SURROUND THESE AREAS. NO DOUBT THAT HEADLINES MAY NEED TWEAKING AS
HIGHLY MESOSCALE DETAILS FOR WHERE HEAVIEST SNOW DEVELOPS BECOMES
MORE APPARENT TONIGHT INTO MONDAY MORNING.
REST OF EXTENDED FEATURES A WARMING TREND MID TO LATE THIS WEEK. MAY
SEE SOME READINGS NEAR 30 DEGREES AGAIN BY NEXT WEEKEND. WEAK
SHORTWAVE CROSSING WESTERN GREAT LAKES ON WED. A LOT OF MID LEVEL
MOISTURE BUT LOW-LEVEL MOISTURE IS LACKING DUE TO ARCTIC HIGH VCNTY
OF UPPER GREAT LAKES. RAN WITH SLIGHT CHANCE POPS SPREADING FM WEST
TO EAST. BEST CHANCE OF SNOW WILL BE OVER KEWEENAW DUE TO THE
FORCING FM THE SYSTEM AND ENOUGH INSTABILITY FOR LAKE ENHANCED SNOW.
INVERSIONS STAY AT 5KFT OR LESS SO NOT EXPECTING HEAVIER SNOW.
ADDITIONAL SHORTWAVE MOVES THROUGH WED NIGHT INTO THU WITH WEAK
TROUGH PASSAGE TIED TO IT. MAY SEE SNOW SHOWERS INCREASING LATE THIS
WEEK CLOSER TO LK SUPERIOR THOUGH TEMPS BARELY BOTTOM OUT AT -
15C...SO LAKE EFFECT SHOULD BE ON THE LIGHTER SIDE WITH LAKE TEMPS 2-
3C.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1249 PM EST SUN JAN 17 2016
AT KIWD/KCMX...NW FLOW LAKE EFFECT CONTINUES INTO MONDAY. EXPECT IFR
VSBY DURING THE HEAVIER SNOW BANDS AT IWD...BUT WILL STAY MVFR FOR
THE MOST PART. IFR/LIFR VSBY AT CMX WILL CONTINUE THROUGH THIS
FORECAST PERIOD AND THIS WILL BE A VARIABLE CONDITION.
AT KSAW...VFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE FORECAST
PERIOD WITH THE LAKE EFFECT SNOW SHOWERS STAYING MOSTLY TO THE EAST.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 408 PM EST SUN JAN 17 2016
A TIGHT GRADIENT WILL REMAIN ACROSS LAKE SUPERIOR INTO EARLY
TUESDAY...KEEPING WIND GUSTS BETWEEN 25-30KTS WITH HIGHER GALE FORCE
GUSTS TO 35 KNOTS POSSIBLE OVER EASTERN LAKE SUPERIOR LATE THIS
AFTERNOON INTO TONIGHT. IN ADDITION...HEAVY FREEZING SPRAY IS
EXPECTED TODAY INTO MONDAY. WINDS ARE EXPECTED TO SLOWLY DIMINISH
TOWARDS THE MIDDLE OF NEXT WEEK...AS HIGH PRESSURE MOVES OVER THE
UPPER GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST MONDAY FOR MIZ002-003-
006-007-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ001-014-
084.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MIZ009-010.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST MONDAY FOR
LSZ263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...- NONE -
MARINE...- NONE -
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1253 PM EST SUN JAN 17 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 550 AM EST SUN JAN 17 2016
LATEST WV IMAGERY AND RAP ANALYSIS INDICATED A COLD MID/UPPER LEVEL
LOW MOVING INTO NW LAKE SUPERIOR. AT THE SFC...LAKE INDUCED TROUGH
HAS KEPT WINDS MORE NORTHERLY OVER LAKE SUPERIOR WHILE OVER UPPER MI
WINDS ARE MORE WEST TO NORTHWEST. RESULTING STRONG LOW LEVEL
CONVERGENCE FROM LAKE INDUCED TROF AND ENHANCEMENT ASSOC WITH MID-
UPR LEVEL LOW HAS RESULTED IN VERY INTENSE AND HEAVY LES BANDS INTO
ALGER AND FAR EASTERN MARQUETTE COUNTIES. REPORTS FROM ALGER COUNTY
SHERIFF IN MUNISING ESTIMATED AROUND A FOOT OF SNOW ACCMULATION
SINCE LATE SATURDAY EVENING WITH SNOWFALL RATES EXCEEDING 3 INCHES
PER HOUR AT TIMES. STRONG CONVERGENCE ALSO SUPPORTING HEAVY SNOW
BAND INTO ONTONAGON WITH SIX INCHES THIS LAST EVENING.
TODAY INTO TONIGHT...GIVEN STRONG LOW-LEVEL CONVERGENCE IN PLACE
WITH DEEP CYCLONIC N-NW FLOW AND ENHANCEMENT FROM MID-UPPER LEVEL
LOW...EXPECT HEAVY LES BANDS TO CONTINUE INTO THE LATE MORNING HOURS
FOR FAR ERN MARQUETTE COUNTY...SO DECIDED TO ISSUED A LES WARNING.
BACKING OF WINDS BEHIND PASSAGE OF SFC TROUGH SOUTH THROUGH ERN
UPPER MI THIS MORNING WILL PUSH HEAVY LES BAND OUT OF ERN MQT COUNTY
AND INTO ALGER AND NRN SCHOOLCRAFT COUNTY. STRONG LOW-LVL
CONVERGENCE SETTING UP OVER ALGER...NRN SCHOOLCRAFT AND COUNTIES
FROM PERSISTENT LAKE INDUCED TROF COMBINED WITH POTENTIAL
ENHANCEMENT FROM SHORTWAVE ROTATING SOUTH ACROSS ERN LAKE SUPERIOR
ON MONDAY WILL CONTINUE FAVORABLE ENVIRONMENT FOR HEAVY LES BANDS.
MODEL SOUNDINGS SUGGEST LAKE INDUCED CAPE NEAR 1000 J/KG AND
EQUILIBRIUM LEVEL TO NEAR 13 KFT WITH DGZ STILL FAVORABLY PLACED
WITHIN CONVECTIVE BOUNDARY LAYER YIELDING 25-30/1 SLR/S. THESE
CONDITIONS COULD EASILY SUPPORT HEAVY LES BANDS WITH SNOWFALL RATES
ON ORDER OF 1 TO 2 INCHES PER HOUR WITHIN MORE INTENSE BANDS FOR
ALGER...NRN SCHOOLCRAFT INTO LUCE COUNTIES. THUS...HAVE DECIDED TO
UPGRADE TO LES WARNINGS FOR NRN SCHOOLCRAFT AND LUCE COUNTIES
CONTINUING THROUGH MONDAY CONSISTENT WITH WARNING ALREADY IN PLACE
FOR ALGER COUNTY. SOME AREAS ACROSS ALGER AND NRN SCHOOLCRAFT COULD
SEE AN ADDITIONAL 20 INCHES OF FRESH SNOWFALL THROUGH MONDAY.
DECIDED TO ISSUE A LES ADVISORY FOR DELTA COUNTY...MAINLY OVER THE
NE PORTION WHERE MODERATE SNOW COULD ACCMULATE UP TO 6 INCHES TODAY.
ALSO ISSUED AN ADVISORY FOR SRN SCHOOLCRAFT TODAY INTO MONDAY AS
AREAS NEAR GERMFASK TO STEUBEN COULD APPROACH 8 TO MAYBE 12 INCHES
OF LES ACCUMULATION.
AS FOR WESTERN COUNTIES...GIVEN REPORT OF HEAVY SNOW IN CITY OF
ONTONAGON AND PERSISTENT STRONG LOW-LVL CONVERGENCE INTO ONTONAGON
AND TWIN LAKES PORTION OF NRN HOUGHTON COUNTY HAVE ALSO DECIDED TO
EXTEND LES WARNING FOR THESE TWO COUNTIES THROUGH MONDAY AS WELL.
BELIEVE STRONG LOW-LVL CONVERGENCE AND DEEP CYCLONIC NW FLOW WILL
OVERCOME SLIGHTLY LESS FAVORABLE DENDRITIC SNOW GROWTH. WOULD NOT BE
SURPRISED TO SEE SEVERAL LOCATIONS APPROACH A FOOT OF ADDITIONAL
SNOWFALL ESPECIALLY OVER PORCUPINE MTNS AND TWIN LAKES AREAS. IN
TURN ALSO DECIDED TO EXTEND LES ADVISORIES FOR SRN HOUGHTON FOR
ADDITIONAL ACCUMULATION OF 4 TO 8 INCHES THROUGH MONDAY.
THE VERY COLD AIR MOVING INTO INTERIOR LOCATIONS WILL DROP WIND
CHILLS INTO THE -20 TO -30 RANGE NEAR THE WI BORDER FROM IRONWOOD TO
CRYSTAL FALLS EARLY THIS MORNING AND AGAIN TONIGHT WHERE A WIND
CHILL ADVY WAS ISSUED. EXPECT ENOUGH LAKE MODERATION FARTHER NORTH
FOR WIND CHILLS MAINLY IN THE -10 TO -20 RANGE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 547 AM EST SUN JAN 17 2016
...LAKE EFFECT SNOW GRADUALLY DIMINISHES MON NIGHT INTO TUE...
UPPER TROUGH OVER THE GREAT LAKES MOVES OVER FAR EASTERN CANADA
EARLY THIS WEEK AND OFF ACROSS THE NORTH ATLANTIC BY WED WHILE
AMPLFIED ZONAL FLOW DEVELOPS OVER THE CONUS. COLD AIR WITH H85 TEMPS
DOWN TO -22C ON MON MORNING EASES BY TUE AND WED AS H85 TEMPS RISE TO
-14C BY LATE TUE INTO WED. LAKE INDUCED TROUGHING PERSISTS THROUGH
MONDAY...BUT UNLIKE THIS MORNING WITH MESOLOW ON THE
TROUGH...APPEARS THAT OVERALL RISING HEIGHTS ALOFT WILL RESULT IN
MORE OF A STEADY STATE CONVERGENT NW FLOW ON MONDAY....FOCUSING OVER
ALGER THROUGH LUCE COUNTIES. SOUNDINGS SHOW SLOWLY DIMINISHING
INSTABILITY...BUT STILL LOOKING AT INVERSIONS NEAR 5KFT OVER WESTERN
CWA AND NEAR 10KFT OVER EAST CWA. SHORTWAVE AND DEEP LAYER FORCING
DROPPING ACROSS LK SUPERIOR AND UPR MICHIGAN...ESPECIALLY EAST HALF
WILL CONTINUE TO LEAD TO HEAVY LAKE ENHANCED SNOW WITH SNOW RATES
OVER 1 INCH PER HOUR. BASED ON HOW THIS EVENT HAS WENT THUS FAR
THOUGH WITH TREMENDOUS HOURLY SNOW RATES AIDED IN LARGE PART BY VERY
HIGH SLR/S OVER 30:1...SHOULD SEE RATES 1-3 INCHES PER HOUR IN THE
HEAVIEST SNOW BANDS. BY MON AFTN...LARGER SCALE FORCING BEGINS TO
DIMINISH AS SHORTWAVE EXITS THE AREA AND Q-VECTOR DIVERGENCE MOVES
IN WITH SUBSIDENCE. INVERSIONS BEGIN TO FALL SHARPLY MON EVENING SO
EVEN THOUGH MAJORITY OF MOIST LAKE EFFECT LAYER REMAINS IN THE
DGZ...EXPECT SNOW INTENSITY TO START TAKING BIGGER HIT. AS THE SFC
RIDGE OVER THE NORTHERN PLAINS ATTEMPTS TO MOVE MORE NORTH OF LK
SUPERIOR...SFC-H925 WINDS VEER NNW FM NW SO MAY SEE SNOW SHOWERS
MOVE BACK OVER MORE AREAS NEAR LK SUPERIOR. WITH THE NEGATIVE
FACTORS MENTIONED INTENSITY SHOULD BE COMING DOWN BUT WILL KEEP POPS
HIGH FOR MAINLY LIGHT SNOW AMOUNTS. LATE ON MON NIGHT WINDS BACK
MORE NW AGAIN...SO EXPECT LAKE EFFECT TO RETURN TO NW SNOW BELTS BY
TUE MORNING WHERE IT SHOULD REMAIN UNTIL TUE NIGHT IN DIMINISHED
STATE AS WINDS BECOME OFFSHORE AS SFC RIDGE MOVES ACROSS.
AS FOR QPF/SNOW...SIMILAR TO LAST NIGHT RAMPED UP QPF/SNOW COMPARED
TO CONSENSUS AND WPC. GIVEN QPF WHICH EXCEEDED TWO TENTHS OF AN INCH
IN 6 HOURS WHERE HEAVIER SNOW BANDS WERE EXPECTED ALONG WITH SLR/S
25-30:1 YIELDED A 12 HOUR SNOWFALL OF 3-6 INCHES OVER WESTERN UPR
MICHIGAN ON MON WITH AMOUNTS MORE TOWARD 5-8 INCHES OVER
ALGER/NORTHERN SCHOOLCRAFT AND LUCE COUNTIES AS PERSISTENT HIGH
INSTABILITY LAKE EFFECT SETUP IS MORE AFFECTED DIRECTLY BY SHORTWAVE
DROPPING SOUTH ACROSS THE AREA THROUGH AT LEAST MID AFTN ON MON.
BASED ON THE HIGHER THAN EXPECTED SLR/S OF THIS EVENT THUS FAR WOULD
NOT BE SURPRISED TO SEE HIGHER SLR/S AND THUS HIGHER SNOW
AMOUNTS...AT LEAST LOCALLY. COORD WITH SHORT TERM FORECASTER AND
DECIDED TO PUT WARNINGS UP FOR NORTHERN SCHOOLCRAFT AND LUCE
COUNTIES AND EXTEND WESTERN UPR MICHIGAN WARNING THROUGH MON. ADVYS
SURROUND THESE AREAS. NO DOUBT THAT HEADLINES MAY NEED TWEAKING AS
HIGHLY MESOSCALE DETAILS FOR WHERE HEAVIEST SNOW DEVELOPS BECOMES
MORE APPARENT TONIGHT INTO MONDAY MORNING.
REST OF EXTENDED FEATURES A WARMING TREND MID TO LATE THIS WEEK. MAY
SEE SOME READINGS NEAR 30 DEGREES AGAIN BY NEXT WEEKEND. WEAK
SHORTWAVE CROSSING WESTERN GREAT LAKES ON WED. A LOT OF MID LEVEL
MOISTURE BUT LOW-LEVEL MOISTURE IS LACKING DUE TO ARCTIC HIGH VCNTY
OF UPPER GREAT LAKES. RAN WITH SLIGHT CHANCE POPS SPREADING FM WEST
TO EAST. BEST CHANCE OF SNOW WILL BE OVER KEWEENAW DUE TO THE
FORCING FM THE SYSTEM AND ENOUGH INSTABILITY FOR LAKE ENHANCED SNOW.
INVERSIONS STAY AT 5KFT OR LESS SO NOT EXPECTING HEAVIER SNOW.
ADDITIONAL SHORTWAVE MOVES THROUGH WED NIGHT INTO THU WITH WEAK
TROUGH PASSAGE TIED TO IT. MAY SEE SNOW SHOWERS INCREASING LATE THIS
WEEK CLOSER TO LK SUPERIOR THOUGH TEMPS BARELY BOTTOM OUT AT -
15C...SO LAKE EFFECT SHOULD BE ON THE LIGHTER SIDE WITH LAKE TEMPS 2-
3C.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1249 PM EST SUN JAN 17 2016
AT KIWD/KCMX...NW FLOW LAKE EFFECT CONTINUES INTO MONDAY. EXPECT IFR
VSBY DURING THE HEAVIER SNOW BANDS AT IWD...BUT WILL STAY MVFR FOR
THE MOST PART. IFR/LIFR VSBY AT CMX WILL CONTINUE THROUGH THIS
FORECAST PERIOD AND THIS WILL BE A VARIABLE CONDITION.
AT KSAW...VFR CONDITIONS WILL CONTINUE THROUGH MOST OF THE FORECAST
PERIOD WITH THE LAKE EFFECT SNOW SHOWERS STAYING MOSTLY TO THE EAST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 550 AM EST SUN JAN 17 2016
A LOW MOVING FROM SOUTHERN ONTARIO TO QUEBEC WILL BRING COLDER AIR
ACROSS LK SUPERIOR THROUGH THE WEEKEND. BEHIND THE LOW...A TROUGH
WILL REMAIN FAIRLY STATIONARY OVER SOUTHERN LAKE SUPERIOR INTO EARLY
TUESDAY...KEEPING WIND GUSTS BETWEEN 25-30KTS WITH HIGHER GALE FORCE
GUSTS TO 35 KNOTS POSSIBLE OVER EASTERN LAKE SUPERIOR LATE THIS
AFTERNOON INTO TONIGHT. IN ADDITION...HEAVY FREEZING SPRAY IS
EXPECTED TODAY INTO MONDAY. WINDS ARE EXPECTED TO SLOWLY DIMINISH
TOWARDS THE MIDDLE OF NEXT WEEK...AS HIGH PRESSURE MOVES OVER THE
UPPER GREAT LAKES REGION.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 7 PM EST MONDAY FOR MIZ002-003-
006-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ001-
013.
LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ014-084.
WIND CHILL ADVISORY UNTIL NOON CST MONDAY FOR MIZ009-010.
LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ007.
LAKE EFFECT SNOW WARNING FROM 4 PM THIS AFTERNOON TO 7 PM EST
MONDAY FOR MIZ007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST MONDAY FOR
LSZ263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...- NONE -
MARINE...VOSS
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1221 PM CST SUN JAN 17 2016
.AVIATION...
/18Z TAFS/
CONCERNS...POTENTIAL FOR MVFR CIGS BEHIND A FRONT THAT ARRIVES
TONIGHT.
LIGHT SOUTH TO SOUTHEAST WINDS WILL PREVAIL THIS AFTERNOON AND
THEN BECOME MORE EASTERLY THIS EVENING AROUND OR JUST AFTER
SUNSET. A FRONT WILL PASS THROUGH OVERNIGHT RESULTING IN NORTH
WINDS LESS THAN 10 KTS. THE FRONT IS EXPECTED TO MOVE ACROSS THE
METROPLEX AROUND 05Z AND KACT AROUND 08Z. NORTH WINDS WILL
CONTINUE TO PREVAIL MONDAY MORNING BUT THE WINDS WILL SHIFT AROUND
TO THE EAST AND SOUTHEAST MONDAY AFTERNOON.
MVFR CIGS CURRENTLY BEHIND THE FRONT IN OKLAHOMA WILL CONTINUE
SLIDING SOUTH TODAY AND TONIGHT. HOWEVER...DO NOT ANTICIPATE THESE
CLOUDS TO MOVE ACROSS THE METROPLEX AIRPORTS AS A BKN DECK BECAUSE
THE LOW LEVEL WINDS ABOVE THE SURFACE ARE EXPECTED TO SHIFT MORE
EAST AND NORTHEASTERLY OVERNIGHT. THIS WILL TEND TO PUSH THE MVFR
CIGS WEST OF THE AIRPORTS. IT IS POSSIBLE THERE MAY BRIEFLY BE
BKN010-015 CONDITIONS AT A FEW OF THE AIRPORTS OVERNIGHT OR MONDAY
MORNING AND WILL CONTINUE TO MONITOR THE TRACKS AND TRENDS. BUT
FOR NOW...WILL INCLUDE A SCT010-015 AT ALL THE TAF SITES BEHIND
THE FRONT.
JLDUNN
&&
.PREV DISCUSSION... /ISSUED 301 AM CST SUN JAN 17 2016/
COLD MORNING IN PROGRESS ACROSS NORTH TEXAS AS A SURFACE HIGH
PRESSURE CENTER MOVES ACROSS THE REGION. WINDS HAVE GONE CALM IN
MANY LOCATIONS AND SURFACE MOISTURE LINGERS. THIS HAS RESULTED IN
AREAS OF SHALLOW FOG IN SOME LOCATIONS. IN OTHERS...WHERE T/TD
SPREADS ARE A LITTLE HIGHER...THICK FROST HAS DEVELOPED. THE FOG
SHOULD BE PATCHY AND SHALLOW AT BEST AND DOES NOT REALLY APPEAR
THAT IT WILL DEPOSIT ICE ON ANY AREA ROADS. AFTER A COLD START...
TEMPERATURES SHOULD REBOUND NICELY INTO THE LOW TO MID 50S BY THIS
AFTERNOON.
THE WARMUP WILL BE BRIEF AS ANOTHER COLD FRONT IS EXPECTED TO MOVE
THROUGH NORTH TEXAS TONIGHT INTO MONDAY MORNING. A LARGE UPPER LOW
WILL BE MOVING THROUGH THE GREAT LAKES REGION DURING THIS TIME AND
WILL ALLOW A 1030MB SURFACE HIGH TO BUILD SOUTHWARD THROUGH THE
PLAINS. TEMPERATURES ARE VERY COLD ACROSS THE UPPER PLAINS WITH
READINGS IN THE -10 TO -20F RANGE ACROSS PARTS OF THE DAKOTAS AND
MINNESOTA. WHILE THE BRUNT OF THE COLDEST AIR WILL STAY WELL TO
OUR NORTHEAST...THE PATTERN IS FAVORABLE TO ALLOW SHALLOW VERY
COLD AIR TO SPILL SOUTHWARD THROUGH THE PLAINS TODAY. AS IS
TYPICAL WITH VERY SHALLOW COLD AIR...THE MODELS ARE USUALLY TOO
WARM WITH TEMPERATURES DUE TO THEIR LACK OF LOW LEVEL RESOLUTION.
THE LATEST HIGH RESOLUTION RAP GUIDANCE DOES GIVE A SMALL HINT
THAT THE AIR MAY BE COLDER ON MONDAY ACROSS NORTH TEXAS THAN
CURRENTLY INDICATED BY THE GFS/NAM/ECMWF. THE LATEST RUN HAS
TEMPERATURES ACROSS PARTS OF CENTRAL OKLAHOMA IN THE LOW 20S ON
SUNDAY EVENING. THIS IS ABOUT 10 DEGREES COLDER THAN THE CURRENT
MOS GUIDANCE. WITH THAT IN MIND...WILL UNDERCUT THE MOS HIGHS FOR
MONDAY...PARTICULARLY NORTH OF I-20. WHILE COLD AIR WILL SPILL
INTO NORTH TEXAS...THE TRAJECTORY OF THE SURFACE HIGH AND THE
PROGRESSIVE NATURE OF THE UPPER PATTERN WILL ENSURE THAT IT WILL
BE SHORT LIVED ACROSS THE REGION. MOSTLY SUNNY SKIES AND A RETURN
TO SOUTHERLY FLOW LATE IN THE DAY ON MONDAY WILL LIKELY MIX SOME
OF THE COLDER AIR BEFORE THE SUN SETS. TEMPERATURES ARE LIKELY TO
BE IN THE LOW/MID 40S ACROSS THE NORTHERN HALF OF THE CWA WITH
UPPER 40S AND LOWER 50S SOUTH OF I-20.
THERE WILL BE SEVERAL SHORTWAVE TROUGHS THAT MOVE THROUGH THE
PLAINS THROUGH NEXT WEEK AND TIMING EACH ONE IS PROVING TO BE
RATHER DIFFICULT. THERE IS STILL QUITE A BIT OF SPREAD IN MODEL
GUIDANCE THROUGH THE END OF THE WEEK. IT DOES APPEAR THAT LOW
LEVEL FLOW WILL BECOME MORE SOUTH/SOUTHWEST ON TUESDAY WHICH WILL
ALLOW FOR A QUICK WARMUP IN TEMPERATURES BACK INTO THE 60S. A WEAK
COLD FRONT WILL MOVE THROUGH ON WEDNESDAY WITH ANOTHER COOL DOWN
BACK TOWARD SEASONAL NORMS. THERE IS A SMALL CHANCE FOR SHOWERS
ALONG THIS FRONT...MAINLY IN OUR SOUTH/SOUTHEAST COUNTIES ALTHOUGH
MOISTURE IS SOMEWHAT LIMITED. SLIGHTLY BETTER RAIN CHANCES APPEAR
TO ARRIVE LATE WEDNESDAY INTO EARLY THURSDAY AS A STRONG SHORTWAVE
MOVES THROUGH THE SOUTHERN PLAINS. THIS RESULTS IN ANOTHER SURFACE
LOW TRACKING ACROSS NORTH TEXAS WITH SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS EXPECTED TO DEVELOP ON THE EAST SIDE OF THE
LOW. A QUICK LOOK AT THE 00Z ENSEMBLE GUIDANCE INDICATES THIS
SHORTWAVE AND ASSOCIATED SURFACE FEATURES IN MOST OF THE ENSEMBLE
MEMBERS...HOWEVER THE TRACK IS QUITE VARIED WITH ABOUT HALF OF
THE GUIDANCE INDICATING RAIN/STORMS ACROSS OUR AREA...AND THE
OTHER HALF FARTHER EAST INTO THE ARKLATEX. THIS RESULTS IN A LOWER
OVERALL CONFIDENCE IN RAIN MIDWEEK BUT WE WILL MAINTAIN 20/30 POPS
LATE WEDNESDAY INTO THURSDAY WITH BEST CHANCES EAST OF INTERSTATE
35.
TEMPERATURES WILL GENERALLY REMAIN WITHIN 5 DEGREES OR SO OF
SEASONAL NORMS THROUGH THE WEEK.
DUNN
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 30 45 41 64 44 / 5 0 0 5 10
WACO, TX 31 51 39 65 46 / 5 0 0 0 10
PARIS, TX 27 44 34 57 43 / 5 0 0 5 10
DENTON, TX 25 43 37 62 41 / 5 0 0 5 5
MCKINNEY, TX 27 44 36 61 43 / 5 0 0 5 10
DALLAS, TX 31 45 41 63 45 / 5 0 0 5 10
TERRELL, TX 30 46 37 61 46 / 5 0 0 5 10
CORSICANA, TX 32 50 39 64 48 / 5 0 0 5 20
TEMPLE, TX 32 54 39 66 49 / 5 0 0 0 10
MINERAL WELLS, TX 28 46 36 65 38 / 5 0 0 0 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
82/58
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
301 PM MST SUN JAN 17 2016
.SHORT TERM...(LATE THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 300 PM MST SUN JAN 17 2016
AFTERNOON WATER VAPOR IMAGERY REVEALED A DEEP POLAR VORTEX NEARLY
STATIONARY NORTH OF THE GREAT LAKES. A HIGH AMPLITUDE RIDGE WAS
SITUATED FROM THE PACIFIC NORTHWEST SOUTH THROUGH CA. SHORTWAVE
DIVED SOUTHEAST ACROSS THE FRONT RANGE AND PLAINS OF WY/NE INTO
INTO EASTERN CO AND WESTERN KS. WEAKENING VORT LOBE EXTENDING
NORTHWEST INTO WESTERN NE/SD WAS PRODUCING BANDS OF VERY LIGHT
SNOW OR FLURRIES. FURTHER WEST...LIGHT SNOW CONTINUED OVER THE
SNOWY/SIERRA MADRE RANGES. LATEST SURFACE ANALYSIS PLACED THE
ARCTIC FRONT FROM NEAR PINE BLUFFS NORTHWEST TO WEST OF DOUGLAS
WY. WESTERLY DOWNSLOPE WINDS LEE OF CENTRAL/SOUTHERN LARAMIE
RANGE AND BREAKS IN CLOUD COVER PUSHED THE MERCURY IN THE MID-UPR
30S...WHILE CHADRON...AND SIDNEY REMAINED IN THE TEENS. WIND GUSTS
ALONG THE I-80 CORRIDOR HAVE AVERAGED 35-45 MPH. WYDOT WEBCAMS
INDICATED LOWERED VISIBILITY IN BLOWING SNOW BETWEEN LARAMIE AND
RAWLINS.
MAIN FORECAST CHALLENGES WILL DEAL WITH SNOW CHANCES AND WINDS.
12Z/18Z SHORT RANGE MODEL GUIDANCE IS IN GOOD AGREEMENT PROGGING
THE POLAR VORTEX TO MOVE EAST TOWARD NEW ENGLAND...WITH THE RIDGE
OUT WEST WEAKENING AS IT SLIDES EAST ACROSS THE FRONT RANGE AND
PLAINS MONDAY. THE NEXT PACIFIC TROUGH MOVING ASHORE IN THE
NORTHWEST TONIGHT...DEEPENS AS IT TRACKS EAST ACROSS THE ROCKIES
AND PLAINS MONDAY NIGHT AND TUESDAY.
THE ARCTIC FRONT OVER THE SOUTHEAST WY PLAINS GETS DISPLACED TO
THE EAST AS WEST-SOUTHWEST FLOW INCREASES AHEAD OF THE NEXT
TROUGH MONDAY. CRAIG-CASPER HEIGHT GRADIENT PEAKS AROUND 50-55
METERS LATE TONIGHT AND MONDAY MORNING...WITH 700MB WINDS NEAR
50 KT FROM THE ARLINGTON AREA SOUTHEAST TO THE SOUTHERN LARAMIE
RANGE. THUS...SUSTAINED WESTERLY WINDS WILL INCREASE TO 30-40
KT WITH GUSTS NEAR 50 KT POSSIBLE FOR WY ZONE 110 THROUGH AT
LEAST MONDAY AFTERNOON. THE STRONG WINDS WILL CONTINUE TO PRODUCE
AREAS OF BLOWING AND DRIFTING SNOW WITH VISIBILITIES REDUCED TO
1/ MILE OR LESS ALONG THE I-80 CORRIDOR BETWEEN LARAMIE AND
RAWLINS. WENT AHEAD AND EXTENDED THE WINTER STORM WARNING FOR
BLOWING SNOW UNTIL 5 PM MONDAY. LIGHT SNOW WILL GRADUALLY TAPER
OFF OVER THE SNOWY/SIERRA MADRES TONIGHT WITH LESS THAN AN INCH
OF ADDITIONAL ACCUMULATION. SNOW WILL THEN INCREASE LATER MONDAY
AFTERNOON WEST OF A DOUGLAS TO LARAMIE LINE WITH THE APPROACH
OF THE NEXT PACIFIC TROUGH. SNOW INCREASES IN COVERAGE AND
INTENSITY MONDAY NIGHT WITH THE PASSAGE OF THE TROUGH. THE
SNOWY/SIERRA MADRES COULD RECEIVE ANOTHER 2-4 INCHES OF SNOW...
WITH LESS THAN AN INCH ELSEWHERE. SNOW WILL END FOR ALL BUT
THE SNOWY/SIERRA MADRES TUESDAY WITH THE QUICK EXIT OF THE
TROUGH. WINDS WILL GRADUALLY DECREASE MONDAY NIGHT AND TUESDAY.
TEMPERATURES TONIGHT WILL RANGE FROM THE 0 TO 10 ABOVE FOR THE
NE PANHANDLE TO THE TEENS AND 20S SOUTHEAST WY. HIGHS MONDAY
WILL BE MILDER...WITH 40S I-25 CORRIDOR/FAR WESTERN NE PANHANDLE
AND 30S LARAMIE VALLEY AND EASTERN NE PANHANDLE. LOWS MONDAY NIGHT
WILL BE IN THE TEENS AND 20S. COOLER TUESDAY WITH HIGHS IN THE 20S
AND 30S.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 300 PM MST SUN JAN 17 2016
ACTIVE WEATHER IN THE LONG TERM WITH WINDS AND SNOW POTENTIAL.
STARTING OFF TUESDAY NIGHT...GOING TO BE WINDY...WITH GFS 700MB
WINDS 45-50KTS ACROSS CARBON AND ALBANY COUNTIES. CRAIG TO CASPER
700MB GRADIENT OFF THE GFS PRETTY CLOSE TO 60MTRS...SO DO THINK
OUR WIND PRONE AREAS WILL HAVE A SHOT AT SEEING WARNING LEVEL
WINDS. DID INCREASE WINDS AT THESE LOCATIONS OVER GUIDANCE TO
REFLECT THIS THINKING.
WINDS STAY STRONG THROUGH MUCH OF WEDNESDAY BEFORE EASING SOME
TOWARDS 00Z. THEY BEGIN TO SHIFT NORTHWESTERLY...A DIRECTION NOT
FAVORABLE FOR BORDEAUX...BUT STILL ELEVATED FOR ARLINGTON AND THE
SOUTH LARAMIE RANGE. BEGIN TO SEE SOME SNOW MOVING BACK INTO OUR
WESTERN COUNTIES WEDNESDAY AFTERNOON/EVENING AS OUR NEXT SHORTWAVE
BEGINS TO PUSH INTO THE AREA. SNOWY AND SIERRA MADRE RANGES SHOULD
GET A DECENT SNOWFALL OUT OF THIS SYSTEM WITH SNOW PERSISTING FROM
WEDNESDAY MORNING THROUGH THURSDAY MORNING. GFS SHOWING PRETTY CLOSE
TO 3/4THS OF AN INCH QPF AND ECMWF AROUND 1/4TH. STILL A WAYS
OUT...BUT WINTER HEADLINES LOOKING TO BE NEEDED OUT THAT WAY FOR
THIS TIME FRAME.
AFTER THE PASSAGE OF THIS SHORTWAVE...WE ARE LOOKING AT A FAIRLY
LONG WINDY PERIOD WITH WARMER TEMPERATURES. GFS 700MB TEMPERATURES
CLIMB ABOVE FREEZING THURSDAY AND REMAIN ABOVE FREEZING THROUGH
FRIDAY. WESTERLY 700MB WINDS OF 35 TO 45KTS SHOULD ALLOW MANY AREAS
EAST OF THE LARAMIE RANGE TO WARM WELL ABOVE FREEZING IN
DOWNSLOPING FLOW.
NEXT SYSTEM ON TRACK FOR THE WEEKEND WITH BOTH THE GFS AND ECMWF
MOVING ANOTHER SHORTWAVE INTO OUR WESTERN COUNTIES SATURDAY
AFTERNOON. BROUGHT CHANCE POPS BACK INTO THE FORECAST SATURDAY NIGHT
INTO SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1011 AM MST SUN JAN 17 2016
AVIATION WEATHER CONCERNS SHIFTING INTO THE PANHANDLE THIS AFTERNOON.
BAND OF SNOW MOVING SOUTH OUT OF SOUTHWESTERN SOUTH DAKOTA WILL IMPACT
KCDR...KAIA AND KSNY WITH LOWER VISIBILITIES THAT COULD LAST THROUGH
THE AFTERNOON. COULD SEE FOG OUT THAT WAY THIS EVENING AS WELL WITH
WINDS GOING LIGHT AND VARIABLE. GENERALLY FOLLOWED HRRR GUIDANCE FOR
THE 18Z TAFS. WILL CONTINUE TO MONITOR CONDITIONS AND UPDATE AS NEEDED.
&&
.FIRE WEATHER...
ISSUED AT 150 PM MST SUN JAN 17 2016
NO FIRE WEATHER CONCERNS FOR THE NEXT FEW DAYS DUE TO SNOWFALL AND
COLD TEMPERATURES. DRIER...MILDER AND BREEZY TO WINDY WEATHER IS
FORECAST FOR THE MIDDLE TO END OF THE WEEK.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST THIS AFTERNOON FOR WYZ112-114.
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR WYZ113-
116.
WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR WYZ110.
NE...NONE.
&&
$$
SHORT TERM...MAJ
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...MAJ
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1014 AM MST SUN JAN 17 2016
.UPDATE...
ISSUED AT 912 AM MST SUN JAN 17 2016
WINTER WEATHER ADVISORY FOR SOUTH LARAMIE RANGE FOOTHILLS...CENTRAL
AND EASTERN LARAMIE COUNTY EXPIRED AT 9 AM. RADAR TRENDS THE PAST
FEW HOURS SHOWED THE BAND OF LIGHT SNOW MOVED INTO NORTHEAST CO
WITH OCCASIONAL FLURRIES IN ITS WAKE. ANOTHER BAND OF LIGHT SNOW
EXTENDED FROM SOUTH CENTRAL MT THROUGH EAST CENTRAL WY INTO THE
NORTHERN NE PANHANDLE. NOT EXPECTING MUCH ACCUMULATION FROM THIS
BAND. LIGHT TO MODERATE SNOW CONTINUES TO FALL OVER THE SNOWY/SIERRA
MADRE AND SOUTH LARAMIE RANGES AT MID MORNING AND WILL CONTINUE
INTO THE EARLY AFTERNOON BEFORE TAPERING OFF. COULD SEE AN ADDITIONAL
1 TO 3 INCHES FOR THESE AREAS. WESTERLY WINDS CONTINUE TO GUST
BETWEEN 30 AND 40 MPH BETWEEN LARAMIE AND RAWLINS. I-80 REMAINS
CLOSED BOTH DIRECTIONS BETWEEN RAWLINS AND LARAMIE DUE TO CONSIDERABLE
BLOWING AND DRIFTING SNOW AND POOR VISIBILITY. HIGH TEMPERATURES
WERE LOWERED A FEW DEGREES FOR THE FAR NORTHEAST CWA...CHADRON TO
ALLIANCE.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 513 AM MST SUN JAN 17 2016
THE BIGGEST CHALLENGE FOR THE NEAR TERM INVOLVES THE SNOW BAND THAT
DEVELOPED NW-SE ACROSS LARAMIE COUNTY EARLIER TONIGHT. THE COLD
FRONT LOOKS AS IF ITS STALLED WITHIN THE SOUTHERN LARAMIE RANGE
FOOTHILLS...WITH GOOD CONVERGENCE ALONG THE FRONT IN ADDITION TO
UPSLOPE FORCING. A LOOK AT MESOANALYSIS SHOWS SOME NEGATIVE EPV
LINED UP ALONG THE FRONT AS WELL...THUS NOT SURPRISED THE BAND
PERSISTED FOR MUCH OF THE NIGHT AND WAS RELATIVELY INTENSE. THE
BAND REMAINS IN PLACE ALONG THE I-80 AT THIS HOUR...ALTHOUGH IS
WEAKENING AND SLOWLY SLIDING SOUTH BASED ON RADAR. SO
FAR...ROUGHLY 3-4 INCHES OCCURRED HERE AT THE OFFICE AND EXPECT
SIMILAR TOTALS ACROSS MUCH OF THE COUNTY...ESPECIALLY THE SOUTHERN
HALF. ANOTHER 1 TO 2 INCHES IS POSSIBLE THROUGH THE MORNING WITH
THIS BAND...SO WENT EXPANDED THE WINTER WEATHER ADVISORY FOR ALL
OF LARAMIE COUNTY. THANKFULLY...WINDS ARE LIGHT SO DO NOT
ANTICIPATE BLOWING SNOW CONCERNS.
THE OTHER CHANGE TO HIGHLIGHTS WAS FOR THE SNOWY RANGE. UPGRADED TO
A WINTER STORM WARNING AS AN INITIAL LOOK AT SNOTEL OBS SHOWED SNOW
TOTALS ALREADY IN THE 6-12 INCH RANGE ACROSS THE MOUNTAIN RANGE.
WITH AT LEAST 4-6 MORE INCHES POSSIBLE THROUGH THE REST OF
TODAY...WENT WITH THE UPGRADE. OTHERWISE...HIGHLIGHTS ARE IN GOOD
SHAPE FOR NOW.
WIND GUSTS HAVE BEEN STEADY IN THE 30 TO 45 MPH RANGE IN THE
SOUTHERN LARAMIE RANGE AND ARLINGTON AREAS WITH OCCASIONAL GUSTS
TO 55 MPH AT ARLINGTON. VISIBILITIES ALONG I-80 BETWEEN ARLINGTON
AND SINCLAIR WITHIN SNOW AND BLOWING SNOW HAVE CONSISTENTLY BEEN
LESS THAN ONE MILE TONIGHT...WITH SOME IMPROVEMENT THIS MORNING AS
SNOWFALL IS LIKELY DIMINISHING. INTERSTATE 80 REMAINS CLOSED
BETWEEN RAWLINS AND LARAMIE AND IS EXPECTED TO BE CLOSED FOR AN
EXTENDED PERIOD. THERE ARE ADDITIONAL CLOSURES ELSEWHERE AS
WELL...BUT WILL NOT GET INTO DETAILS HERE. LIGHT SNOW HAS BEEN
REPORTED AT MANY OTHER LOCATIONS ACROSS SOUTHEAST WYOMING AND THE
SOUTHERN NEBRASKA PANHANDLE TOO...BUT EXPECT MOST OF THESE
LOCATIONS SAW JUST A TRACE...PERHAPS UP TO HALF INCH. GUSTY WINDS
AND LIGHT SNOW WILL CONTINUE THROUGH THE MORNING.
FOR THE REMAINDER OF TODAY...EXPECT SNOW TO STEADILY DIMINISH WHILE
WINDS REMAIN FAIRLY STEADY...PERHAPS INCREASING LATER TONIGHT.
THE CAG-CPR GRADIENT WILL STRENGTHEN TONIGHT AS THE COLD FRONT
BEGINS TO RETREAT EAST. 700-750 MB WINDS INCREASE TO ROUGHLY 40 TO
50 KTS IN THE WIND CORRIDOR DURING THIS TIME MEANING WINDS WILL
LIKELY BUMP BACK UP IN TO THE 45 TO 55 MPH RANGE MORE
CONSISTENTLY. BLOWING SNOW WILL REMAIN AN ISSUE...THUS THE CURRENT
WINTER HIGHLIGHTS MAY NEED TO BE EXTENDED DEPENDING ON HOW THE
SNOWPACK EVOLVES TODAY. OTHERWISE...WIND HIGHLIGHTS MAY NEED TO BE
CONSIDERED. MONDAY WILL CONTINUE TO BE BREEZY-WINDY AND WARMER AS
ZONAL FLOW TAKES OVER FOR A BRIEF PERIOD. THE NEXT SHORTWAVE
TROUGH WILL BRING A CHANCE FOR SNOW TO THE AREA MONDAY NIGHT.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 513 AM MST SUN JAN 17 2016
SOME LINGERING SNOW SHOWERS SHOULD CONTINUE OVER THE HIGHER MTNS
TUESDAY AND TUESDAY NIGHT WITH COOL AND DRY WEATHER EXPECTED
ELSEWHERE OVER THE CWA AS A SHORT UPPER RIDGE MOVES EAST ACROSS
THE REGION. NEXT SHORTWAVE IN THE PROGRESSIVE UPPER FLOW WILL THEN
SCOOT ACROSS THE AREA WEDS INTO WEDS NIGHT BRINGING A MINOR COOL
FRONT AS WELL AS ANOTHER ROUND OF SCTD SNOW SHOWERS. LARGER
AMPLITUDE UPPER RIDGE THEN APPROACHES AND MOVES BY THURSDAY
THROUGH FRIDAY ALLOWING FOR MILDER TEMPERATURES. THIS RIDGE
WEAKENS AND MOVES EAST ON SATURDAY WITH THE NEXT UPPER SHORTWAVE
BRINGING A RETURN OF SNOW SHOWER TO THE WESTERN CWA BY LATE IN THE
DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1011 AM MST SUN JAN 17 2016
AVIATION WEATHER CONCERNS SHIFTING INTO THE PANHANDLE THIS
AFTERNOON. BAND OF SNOW MOVING SOUTH OUT OF SOUTHWESTERN SOUTH
DAKOTA WILL IMPACT KCDR...KAIA AND KSNY WITH LOWER VISIBILITIES
THAT COULD LAST THROUGH THE AFTERNOON. COULD SEE FOG OUT THAT WAY
THIS EVENING AS WELL WITH WINDS GOING LIGHT AND VARIABLE.
GENERALLY FOLLOWED HRRR GUIDANCE FOR THE 18Z TAFS. WILL CONTINUE
TO MONITOR CONDITIONS AND UPDATE AS NEEDED.
&&
.FIRE WEATHER...
ISSUED AT 513 AM MST SUN JAN 17 2016
FIRE WEATHER CONCERNS WILL REMAIN MINIMAL THROUGH THE NEAR TERM
DUE TO RECENT ACCUMULATING SNOW AND COLD TEMPERATURES. WINDS WILL
REMAIN STRONG AT TIMES IN THE WIND PRONE AREAS THROUGH MONDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 5 PM MST THIS AFTERNOON FOR WYZ110-
112-114.
WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR WYZ113-
116.
NE...NONE.
&&
$$
UPDATE...MJ
SHORT TERM...RJM
LONG TERM...RE
AVIATION...GCC
FIRE WEATHER...RJM