Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/27/14
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
838 PM MST WED NOV 26 2014
.UPDATE...
ISSUED AT 824 PM MST WED NOV 26 2014
NO CHANGES PLANNED TO EVENING FORECAST. SATELLITE IMAGERY AND
OBSERVATIONS STILL SHOWING SOME MID LEVEL CLOUDS ACROSS THE FAR
NORTHEAST PLAINS OF COLORADO. SHORT RANGE MODELS CONTINUE TO FLUSH
OUT THE REMAINDER OF THE MOISTURE THROUGH THE NIGHT WITH CLEARING
SKIES.
SOME MOUNTAIN WAVE CLOUDS REMAIN ALONG THE FRONT RANGE WITH
CONTINUED GUSTY WINDS OVER HIGHER MOUNTAINS AND EAST SLOPES.
OBSERVATIONS STILL SHOWING SOME GUSTS IN THE 40 TO 60 MPH RANGE
OVER HIGHER MOUNTAINS. THIS WILL LIKELY CONTINUE AS MOUNTAIN TOP
STABILITY INCREASES FURTHER OVERNIGHT. AT THIS TIME...EXPECT
HIGHEST WINDS GUSTS BELOW THE 75 MPH THRESHOLD FOR HIGH WINDS.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH THURSDAY)
ISSUED AT 305 PM MST WED NOV 26 2014
AN UPPER LEVEL RIDGE OVER THE WESTERN STATES WILL FLATTEN AS IT
SHIFTS EAST OVER THE GREAT BASIN THURSDAY. THIS WILL CAUSE THE
NORTHWEST FLOW ALOFT OVER COLORADO TO BECOME WEST-NORTHWESTERLY
TOMORROW. SOME CLOUDS ARE LINGERING OVER THE MOUNTAINS AND PERHAPS A
FEW FLURRIES TOO. THERE IS ALSO A SLIGHT CHANCE FOR LIGHT SNOW OVER
THE NORTHEAST PLAINS THIS EVENING. THE HRRR SHOWS A SMALL BAND
REFORMING THIS EVENING. NOT SOLD ON THIS...SO WILL STICK TO THE
SLIGHT CHANCE. IF ANY SNOW FORMS...IT SHOULD BE LIGHT.
A SURFACE HIGH PRESSURE OVER THE EASTERN PLAINS AND A
SURFACE TROUGH ALONG THE BASE OF THE FOOTHILLS HAS KEPT THE COOLER
AIR OVER NORTHEAST COLORADO TODAY. THE LEE SIDE TROUGH ALONG WITH
HIGHER PRESSURE OVER THE GREAT BASIN HAS PRODUCED WINDY CONDITIONS
IN THE MOUNTAINS AND FOOTHILLS. TEMPERATURES HAVE WARMED NICELY IN
THE LOWER FOOTHILLS WITH READINGS IN THE UPPER 40S. AS HIGH PRESSURE
SHIFTS EAST OF THE REGION AND A SURFACE TROUGH DEEPENS OVER THE
NORTHERN ROCKIES...SOUTH TO SOUTHWEST WINDS WILL FLUSH OUT THE
COOLER AIR OVER NORTHEAST COLORADO AND LEAD TO MILD TEMPERATURES FOR
THANKSGIVING. THERE WILL STILL BE SOME MOISTURE AT THE MID AND UPPER
LEVELS...SO WAVE CLOUDS ARE EXPECTED AT TIMES. THIS MAY SLOW WARMING
SOME...BUT STILL LOOKS LIKE HIGHS WILL CLIMB ABOVE 60 DEGREES ACROSS
NORTHEAST COLORADO. WINDS WILL BE GUSTY IN THE FOOTHILLS AND
MOUNTAINS AGAIN WITH GUSTS TO 50 TO 60 MPH IN THE WIND PRONE AREAS
OF THE MOUNTAINS AND FOOTHILLS.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 305 PM MST WED NOV 26 2014
...A DRY AND WARM PATTERN IS SETTING UP FOR FRIDAY THROUGH
SUNDAY...
STARTING WITH FRIDAY A DRY AIRMASS WILL BE IN PLACE WITH STRONG
WNW FLOW ALOFT. ACCORDING TO MODEL CROSS-SECTIONS A MOUNTAIN WAVE
WILL FORM THURSDAY EVENING INTO EARLY FRIDAY. SUSTAINED WINDS OF
40 TO 45 MPH WITH GUSTS UP TO 70 WILL BE POSSIBLE OVER THE HIGHER
MOUNTAIN PEAKS. THERE IS A LACK OF AN INVERSION LAYER AT MOUNTAIN
TOP SO IT WILL DIFFICULT TO BRING THOSE WINDS DOWN TO THE SURFACE
SO HIGHER WINDS SHOULD REMAIN WITHIN THE MOUNTAINS.
HOWEVER...CHINOOK WARMING WILL OCCUR ON FRIDAY AND AID IN GETTING
AREAS CLOSE TO THE FOOTHILLS WELL ABOVE SEASONAL NORMALS. CURRENT
TRENDS HAVE HIGHS IN THE LOWER 70S FOR THE DENVER METRO. THIS
WOULD EITHER MEET OR EXCEED THE CURRENT RECORD HIGH FOR FRIDAY OF
72 SET BACK IN 1901.
DRY PATTERN CONTINUES INTO SATURDAY AND EARLY SUNDAY WITH
WESTERLY FLOW BECOMING MORE DOMINANT. WINDS OVER THE MOUNTAINS
WILL CONTINUE WITH GUSTING TO 70 MPH STILL POSSIBLE OVER MOUNTAIN
TOP. MOUNTAIN TOP STABILITY IS STILL LACKING SO WILL KEEP WINDS
ISOLATED TO THE MOUNTAINS FOR THE TIME BEING. TEMPERATURES WILL
CONTINUE TO BE WELL ABOVE SEASONAL NORMALS WITH HIGHS ON SATURDAY
IN THE UPPER 60S.
FOR SUNDAY...MODELS STILL INDICATING A STRONG MOUNTAIN WAVE IN THE
MORNING WITH WINDS CONTINUING TO GUST TO 60-65 OVER MOUNTAIN
PEAKS. THE MAIN FEATURE HOWEVER FOR THIS TIMEFRAME IS AN ELONGATED
UPPER LEVEL TROF MOVING THROUGH THE REGION BRINGING A BACKDOOR
COLD FRONT INTO THE EASTERN PORTIONS OF THE STATE. THIS WILL BRING
HIGH TEMPERATURES DOWN SIGNIFICANTLY WITH THE PLAINS STRUGGLING
TO GET OUT OF THE 40S. MOISTURE STILL LACKING WITH THIS SYSTEM SO
LEFT POPS OUT.
FOR MONDAY AND TUESDAY...MODELS ARE STILL IN DISAGREEMENT WITH THE
TIMING OF THE SYNOPTIC FEATURES FOR THE NEXT SYSTEM. THE GFS SHOWS
WESTERLY FLOW WITH INCREASING MOISTURE AHEAD OF THE FRONT WITH
LITTLE PRECIP ASSOCIATED...WHILE THE EC HAS A MORE NORTHWEST FLOW
WITH RAIN MOVING INTO THE WESTERN PORTIONS OF THE STATE BY MONDAY
MORNING. WILL KEEP CURRENT POPS WITH NO CHANGES FOR THIS PERIOD.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z THURSDAY MORNING)
ISSUED AT 835 PM MST WED NOV 26 2014
VERY LIGHT AND VARIABLE WINDS AT TERMINALS AT THIS TIME BUT MORE
DRAINAGE WINDS OUT OF THE SOUTH BY 06Z OR SO. WILL SEE VARYING
AMOUNTS OF MID-HIGH LEVEL MOISTURE WITH WAVE CLOUD REMAINING OVER
THE FRONT RANGE TONIGHT AND THURSDAY. MAY SEE SOME GUSTY WEST
WINDS TO 25KT DEVELOPING AT BJC BETWEEN 11Z AND 18Z WITH DOWNSLOPE
FLOW.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ENTREKIN
SHORT TERM...MEIER
LONG TERM...BOWEN
AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
355 AM EST Tue Nov 25 2014
...Another Day and Night of Rain on Tap for Most Areas Along with
Cooler Temperatures...
.Near Term [Through Today]...
A band of moderate to heavy rain and embedded thunderstorms has
developed across our forecast area early this morning, just along a
surface cold front. The surface cold front will push southeast of
our area today, but rain will be maintained along the sloped frontal
surface to the northwest as a strong shortwave ejects east across
Texas. The response to the ejecting wave will be a strengthening
frontogenetic circulation - especially in the 18-00Z time frame.
Model consensus places the strongest 925-700mb UVV roughly right
where the rain band is already positioned as of 08Z - from Mexico
Beach, to Quincy, to Tifton, and 25-30 miles either side of that.
Rain should initially be quite focused in this narrow band, but will
eventually expand in coverage as 00Z approaches with cyclogenesis
commencing in the eastern Gulf of Mexico. During the daytime hours,
though, we expect a sharp gradient in rain chances due to some dry
low-level air working in behind the cold front. Model forecast cross
sections cut through the front across our area from NW-SE show a
wedge of drier air from roughly ECP-BIJ and to the northwest. This
should limit northwestward progress of measurable rain today,
although even our northwest zones should see some light rain by
tonight. Given the strength of the frontogenetic circulation and
precipitable water values about 1.5 to 2 standard deviations above
normal, it is likely we will see some heavy rain at times today,
particularly in the f-gen band. Heavy rain wording was added to the
forecast with 12-hr QPF of 1.0-1.5" on average in those areas. To
the southeast, scattered showers and thunderstorms should gradually
increase in coverage through the day as low-level ascent becomes
stronger with the developing surface low in the eastern Gulf.
We went with a non-diurnal temperature trend for today. Cooler air
will be working its way southeast across the area in the morning
behind the surface cold front. However, abundant cloud cover and
rain will likely maintain temperatures in the 50s for all but the
eastern Florida Big Bend. By 18-20Z, the coolest temperatures in our
area should be in the low 50s, roughly along the same rain band axis
described earlier (Mexico Beach - Quincy - Tifton). Therefore, highs
for a significant part of our area may occur early in the morning.
The hourly temperatures were a blend of the RAP and 4km NSSL-WRF.
.Short Term [Tonight Through Thursday]...
Isentropic ascent of the 300K surface will be strongest during the
hours centered around 00Z Wednesday as the front remains stalled
over the area under parallel southwesterly flow aloft. DPVA will
also be in play. Therefore, we start out with categorical PoPs
across the board, as high as 100% across roughly the eastern half of
the forecast area. After that, forcing for ascent will drop off
precipitously after midnight with all PoPs ending before 18Z
Wednesday. For additional rainfall totals and any flooding concerns,
see the hydrology section below.
As cyclogenesis jumps to the coastal Carolinas, the colder air will
finally be drawn completely across the forecast area tonight. In
fact, temperatures will be chilly throughout this period. Look for
low temps by dawn Wednesday to range from the upper 30s over
Southeast AL and adjacent portions of the FL Panhandle to the upper
40s across the Southeast FL Big Bend. Highs both Wednesday and
Thursday will generally be closer to what we see in January with
lowers 60s common. A few spots across our northern zones will not
even quite make it to 60. Overnight lows Wednesday night will
generally be in the mid to upper 30s inland with 40s near the coast.
.Long Term [Thursday Night Through Tuesday]...
This period will be dry with surface high pressure in control.
Heights will also rise with zonal flow in place from the weekend
into Monday. However, the chilly air mass will remain in place
through Friday night with temps near or below even normal midwinter
levels. A few spots across the northern fringe of the forecast area
could touch freezing Thursday night and there could be some frost
Friday night. A moderating trend is expected from the weekend into
Monday. Some areas will see lower 70s degrees by Sunday with most
areas getting there on Monday.
&&
.Aviation...
[Through 06Z Wednesday] In general, there was a gradient in
observed conditions as of TAF issuance time from VFR to the
northwest, to IFR to the southeast, across the area. We expect
that trend to continue through the day, although it is likely
model guidance is being too optimistic with CIGS. A steady, cool
rain is forecast at most of the terminals, and that should help
lower cloud bases. In general, we are forecasting CIGS to trend
down into IFR or low-end MVFR at TLH and VLD, and trend down to
MVFR at ECP and ABY. DHN is most likely to stay at VFR for much of
the period. Visibility may be briefly reduced into the IFR range
at times in heavier rain or thunderstorms.
&&
.Marine...
Small craft advisory conditions will first be achieved with offshore
winds speeds this morning. The nearshore legs will not see this
until later in the day. Winds will be strongest overnight and an
occasional gust to gale force will be possible. Conditions will drop
below advisory criteria, even offshore, Wednesday morning. After a
brief lull Wednesday afternoon, a return to cautionary conditions is
expected from Wednesday night into Friday. Winds will then drop
below headline criteria for Friday night and Saturday as they
finally veer to onshore.
&&
.Fire Weather...
Wetting rains are expected today with high RH. Drier air will arrive
on Wednesday and Thursday, but RH values are not currently forecast
to reach critical levels. Additionally, fuel moisture will be quite
high given recent rainfall.
&&
.Hydrology...
Radar estimates that 2.5-3.5 inch rainfall totals have been common
since Saturday across most of our GA zones as well as northern and
western portions of the FL Big Bend and adjacent Panhandle. This is
causing rises on most area rivers. These slow rises will continue
for the next several days. Additional rainfall totals through
tonight will be around 2-2.5 inches for the southeastern 1/2 of
the forecast area. These rains are not expected to cause
significant areal or riverine flooding. However, the Ochlockonee
River could approach minor flood stage in 4-5 days.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 61 43 62 37 64 / 100 100 10 10 0
Panama City 57 44 63 45 63 / 100 90 10 10 0
Dothan 54 40 60 39 60 / 50 90 10 10 0
Albany 56 42 61 37 61 / 80 100 20 10 0
Valdosta 62 46 61 37 62 / 100 100 20 10 0
Cross City 68 49 64 37 65 / 90 100 20 10 0
Apalachicola 62 46 62 44 64 / 100 100 10 10 0
&&
.TAE Watches/Warnings/Advisories...
FL...None.
GA...None.
AL...None.
GM...Small Craft Advisory from 4 PM this afternoon to 7 AM EST
Wednesday for Apalachee Bay-Coastal waters From Ochlockonee
River to Apalachicola FL out to 20 NM-Coastal waters from
Suwannee River to Keaton Beach FL out 20 NM-Coastal waters
from Apalachicola to Destin FL out 20 NM.
Small Craft Advisory until 10 AM EST Wednesday for Waters from
Suwannee River to Apalachicola FL from 20 to 60 NM-Waters
from Apalachicola to Destin FL from 20 to 60 NM.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...WOOL
LONG TERM...WOOL
AVIATION...LAMERS
MARINE...WOOL
FIRE WEATHER...LAMERS
HYDROLOGY...WOOL
AREA FORECAST DISCUSSION
NWS BOISE ID
956 AM MST TUE NOV 25 2014
.DISCUSSION...WARM FRONTAL SNOW CHANGING TO RAIN TODAY WILL EXIT
THE AREA FROM SW TO NE AS THE DAY WEARS ON. NE VALLEY COUNTY WILL
BE THE LAST TO IMPROVE. LATEST HRRR HOLD ON TO LIGHT RAIN THERE
THROUGH AROUND 3Z AND MID LEVEL CLOUDS ACROSS THE EAST PORTIONS OF
THE WEST CENTRAL AND BOISE MOUNTAINS BEYOND 6Z. NO CHANGES FOR THE
MORNING UPDATE. WILL REVIEW TIMING WITH AFTERNOON PACKAGE.
&&
.AVIATION....MVFR-IFR RAIN AND SNOW SHOWERS NORTHEAST OF A LINE FROM
KBKE-KONO-KMUO-KSUN. OTHERWISE...VFR. RAIN AND SNOW SHOWERS ENDING
BY 21Z. SURFACE WINDS...SE 5-15 KTS THIS MORNING...EXCEPT BECOMING
SOUTHWESTERLY 15-25KT IN SE OR AND MAGIC VALLEY DURING
AFTERNOON...WITH GUSTS TO 35KT POSSIBLE IN MAGIC VALLEY. WINDS ALOFT
NEAR 10K FEET MSL...NW 35-50KT SOUTHWEST OF KBNO-KTWF LINE...NW 55-
75KT NORTHEAST OF KBNO-KTWF LINE...SUBSIDING TO NW 25-40KT BY 15Z
WED.
&&
.PREV DISCUSSION...
SHORT TERM...TODAY THROUGH WEDNESDAY...SNOW CONTINUES TO PILE UP
IN THE BOISE MOUNTAINS AND WEST CENTRAL MOUNTAINS THIS MORNING.
WEBCAMS SHOW THAT THE ROADS ARE SNOW-COVERED AS SEVERAL INCHES OF
SNOW HAVE ALREADY ACCUMULATED...WITH 5 INCHES SO FAR OVERNIGHT IN
MCCALL. A MOIST PACIFIC PLUME RESIDES OVER THE AREA...WITH THE
TREASURE VALLEY ON THE SOUTHERN EDGE OF THE PLUME. AREAS TO THE
SOUTH AND EAST OF THE TREASURE VALLEY WILL EXPERIENCE OCCASIONAL
RAIN SHOWERS AND HIGH ELEVATION SNOW SHOWERS THIS MORNING BEFORE
TAPERING OFF THIS AFTERNOON. MEANWHILE...THE BOISE/WEST CENTRAL
MOUNTAINS WILL SEE ADDITIONAL SNOW ACCUMULATIONS THIS MORNING
WHICH WILL THEN TAPER OFF THIS AFTERNOON. A WINTER WEATHER
ADVISORY IS IN EFFECT. SNOW LEVELS NEAR VALLEY FLOORS IN THE
NORTHERN MTNS WILL RISE TO ABOVE 5000 FEET THIS AFTERNOON AS A
WARM FRONT MOVES FROM SE OREGON INTO SW IDAHO. TEMPERATURES WILL
BE WARMER THIS AFTERNOON AS WARMER AIR ACCOMPANIES THE BUILDING
UPPER RIDGE. PRECIP WILL LINGER IN THE FAR NORTH TONIGHT...ENDING
ON WEDNESDAY AS THE CREST OF THE UPPER RIDGE REACHES OUR AREA.
TEMPERATURES TODAY AND WEDNESDAY WILL BE ABOVE NORMAL...WITH HIGHS
IN THE 40S ACROSS THE NORTH AND 50S ACROSS THE SOUTH - INCLUDING
THE TREASURE VALLEY AND WESTERN MAGIC VALLEY. STRONG W-NW WINDS
ALOFT WILL MIX DOWN TO THE SURFACE IN SOME AREAS BY THIS
AFTERNOON. NEAR ADVISORY SPEEDS AND GUSTS ARE EXPECTED IN THE
OWYHEE MOUNTAINS AND IN THE WESTERN MAGIC VALLEY. WINDS WILL BE
LIGHTER ON WEDNESDAY AS THE W-NW WINDS ALOFT WEAKEN.
LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY...A TROUGH NOW NEAR
40N AND 150W WILL SLOWLY MEANDER TOWARDS THE WEST COAST THROUGH
THE EXTENDED PERIOD CREATING AN UPPER LEVEL RIDGE THAT WILL SLOWLY
BREAK DOWN BY FRIDAY MORNING. MOISTURE FROM THIS SYSTEM WILL STAY
NORTH OF THE RIDGE ALONG AN ARCTIC BOUNDARY. TEMPERATURES WILL BE
WELL ABOVE NORMAL THROUGH FRIDAY. SOUTHEAST WINDS IN BOISE WILL
AID IN MIXING THE WARM TEMPERATURES ALOFT AND TEMPERATURES NEAR 60
ARE POSSIBLE ON THURSDAY AFTERNOON. MODELS DO NOT HAVE A GOOD
HANDLE ON THE SNOW COVER AROUND THE AREA...THUS HAVE IGNORED THE
COLDER GUIDANCE AS THESE MODELS HAVE TOO MUCH SNOW COVER AND THUS
ARE MUCH COOLER. BY FRIDAY THE RIDGE BREAKS DOWN AND THE ARCTIC
BOUNDARY MOVES SOUTHWARD TOWARDS THE COLUMBIA BASIN. DO NOT THINK
THE COLD AIR WILL REACH THE FORECAST AREA AS THE ARCTIC FRONT
STALLS ALONG THE BLUE MOUNTAINS NORTH OF THE REGION. THE TROUGH
OFF THE COAST IS OVERTAKEN BY A STRONG TROUGH DIVING SOUTH OUT OF
THE GULF OF ALASKA BY SATURDAY. SOUTHERLY FLOW WILL DEVELOP AHEAD
OF THIS TROUGH OVER THE GREAT BASIN ALLOWING FOR WEAK RIDGING
AHEAD OF THE SYSTEM MONDAY INTO TUESDAY BEFORE THE SYSTEM MOVES
INLAND.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WINTER WEATHER ADVISORY UNTIL 5 PM MST THIS AFTERNOON IDZ011-013.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...VM
AVIATION.....JS
PREV SHORT TERM...BW
PREV LONG TERM....KA
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1139 AM CST TUE NOV 25 2014
.SHORT TERM...
303 AM CST
THROUGH WEDNESDAY...
PRIMARY FORECAST CHALLENGE TODAY IS CLOUD COVER. GUIDANCE IS ALL
FAIRLY AGGRESSIVE IS CLEARING THINGS OUT THIS AFTERNOON SAVE FOR THE
WRF-NAM. MODELS ARE OFTEN TOO QUICK TO CLEAR STRATUS OUT IN THE
WINTER...THOUGH IN THIS CASE IT IS A FAIRLY TRANSIENT PATTERN SO
STRATUS MAY BE A BIT QUICKER TO CLEAR THAN IS TYPICAL. MOS GUIDANCE
KEEPS SKIES FAIRLY CLOUDY AND HAVE MAINTAINED CLOUDINESS LONGER THAN
GUIDANCE SUGGESTS BUT DO PARTIALLY CLEAR SKIES OUT TONIGHT FOR A
TIME BEFORE CLOUDS ROLL BACK IN AHEAD OF THE NEXT SYSTEM.
SPEAKING OF THE NEXT SYSTEM...GUIDANCE CONTINUES TO TAKE THE CLIPPER
ON THE SOUTHERN ROUTE WITH ITS PRECIP LARGELY MISSING OUR CWA. HAVE
MAINTAINED SOME SLIGHT CHANCE POPS IN OUR SOUTHWESTERN MOST CWA
WEDNESDAY BUT OTHERWISE CONTINUED THE TREND FROM THE DAY SHIFT OF
LOWERING POPS...COMPLETELY REMOVING THEM FROM MUCH OF THE CWA.
IZZI
&&
.LONG TERM...
303 AM CST
WEDNESDAY NIGHT ONWARD...
IN THE LONGER TERM GUIDANCE IS STILL BRINGS IN A TRANSIENT BUT
MODERATELY POTENT SHOT OF COLD AIR THANKSGIVING DAY WHEN HIGHS
SHOULD ONCE AGAIN HOLD IN THE 20S. LARGE SCALE PATTERN WILL BEGIN TO
TRANSITION TO MORE OF A ZONAL FLOW BY FRIDAY WITH WARM AIR ADVECTION
BEGINNING AND POSSIBLY PRODUCING A BIT OF LIGHT PRECIP...BUT IF
ANYTHING DOES FALL AMOUNTS LOOK TO BE VERY LIGHT. BY SATURDAY STRONG
LOW PRESSURE IS PROGGED TO TRACK EAST INTO THE UPPER GREAT LAKES
ALLOWING FOR A BRISK BUT MILD SOUTHERLY FLOW TO DEVELOP OVER THE
AREA. FORECAST 850MB TEMPS WOULD SUPPORT HIGHS WELL INTO THE 50S AND
PERHAPS NEAR 60...THOUGH 925MB TEMPS ARE NOT QUITE AS MILD AND THAT
COULD PARTIALLY BE A RESULT OF A BIT MORE SNOW COVER. HAVE RAISED
HIGHS A BIT OVER THE BLENDED INITIALIZATION BUT THINKING CURRENT
FORECAST IS STILL TOO COOL...ESPECIALLY IN AREAS WITH LITTLE OR NO
SNOW COVER WHICH SHOULD BE A LARGE PORTION OF THE CWA BY SATURDAY.
COLD FRONT LOOKS TO MOVE THROUGH SAT NIGHT OR SUNDAY BRINGING COOLER
WEATHER FOR A COUPLE DAYS BUT IN THE TRANSIENT RATHER ZONAL FLOW GFS
AND ECMWF BOTH HINT AT ANOTHER HEALTHY WARM UP TOWARD MIDDLE OF NEXT
WEEK. PRECIP CHANCES THROUGH THE PERIOD LOOK LOW AND LARGELY
INCONSEQUENTIAL IF ANYTHING DOES FALL.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* NONE.
RC
//DISCUSSION...UPDATED 18Z...
QUIET AVIATION WEATHER FOR NEXT 30 HOURS...AS SNOW ASSOCIATED WITH
WEAK LOW PRESSURE PASSING TO SOUTHWEST ON WEDNESDAY WILL REMAIN TO
THE SOUTHWEST OF THE TERMINALS. MID MVFR CIGS AT GYY SHOULD
SCATTER WITHIN NEXT HOUR OR SO AND MVFR OVER WISCONSIN EXPECTED TO
STAY TO THE NORTH THIS AFTERNOON...THOUGH COULD SEE FEW TO SCT
CLOUDS AT 020 FILL BACK IN A BIT. WIND SPEEDS WILL REMAIN
GENERALLY LIGHT THROUGHOUT THE TAF PERIOD...WITH DIRECTIONS
SHIFTING TO SOUTHERLY OVERNIGHT...SOUTHEAST WEDNESDAY MORNING AND
EAST-NORTHEAST BY MID TO LATE WEDNESDAY AFTERNOON.
RC
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH IN ALL ELEMENTS.
RC
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...SLIGHT CHANCE OF LIGHT SNOW.
THURSDAY...VFR.
FRIDAY...SLIGHT CHANCE OF LIGHT RAIN OR SNOW.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...VFR.
RODRIGUEZ
&&
.MARINE...
436 AM CST
AS LOW PRESSURE OVER NORTHERN QUEBEC CONTINUES TO LIFT NORTH
TODAY...A TROUGH OF LOW PRESSURE AND FRONTAL BOUNDARY EXTENDING
FROM THIS LOW SOUTHWEST THROUGH THE CENTRAL GREAT LAKES WILL SHIFT
TO THE EASTERN GREAT LAKES AND SOUTHERN QUEBEC. WHILE THIS IS
OCCURRING...EXPECT THE ONGOING DIMINISHING TREND WITH THE
NORTHWEST AND WEST WINDS IN PLACE TO CONTINUE. WINDS ARE CURRENTLY
TO 30 KT ACROSS THE LAKE EARLY THIS MORNING BUT DO EXPECT THEM TO
DIMINISH TO 15 TO 25 KT THIS MORNING...AND THEN TO 10 TO 20 KT IN
THE AFTERNOON. BUILDING HIGH PRESSURE ACROSS THE REGION WILL
PROVIDE A PERIOD OF LIGHTER WINDS OVER THE LAKE TONIGHT INTO
WEDNESDAY AND PART OF WEDNESDAY NIGHT. DEPARTING LOW PRESSURE TO
THE SOUTH OF THE LAKE AND ANOTHER HIGH BUILDING ACROSS THE PLAINS
WILL HELP PROVIDE A TIGHTER PRESSURE GRADIENT OVER THE
LAKE...HELPING RETURN STRONGER WINDS BACK OVER THE LAKE THURSDAY
INTO THURSDAY NIGHT.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 4 PM TUESDAY.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1128 AM CST Tue Nov 25 2014
.UPDATE...
ISSUED AT 938 AM CST TUE NOV 25 2014
Large area of stratocumulus continues to sag southeast across the
forecast area, with the last holdouts near Lawrenceville now
clouding up. A narrow area of clearing from Peoria southeast has
been shifting toward Bloomington and Champaign, although this is
also starting to show a bit of filling in on the latest visible
satellite imagery. At present, the northern edge of the cloud deck
is advancing across northwest Illinois and is approaching
Galesburg from the north. The latest RAP and HRRR guidance shows
some additional development in that area over the next couple
hours, so we will need to keep an eye on that. For now, it looks
like the bulk of the clearing will begin across the southwest CWA
soon and slowly pull northeast.
Have made some adjustments to the high temperatures across the
northern CWA, where it`s still only in the lower 20s, and the
latest sky grids have been sent as well.
&&
.SHORT TERM...(Today)
ISSUED AT 312 AM CST TUE NOV 25 2014
Low pressure that brought widespread rain to central Illinois on
Sunday is now over Quebec, with trailing cold front approaching the
East Coast. Despite the parent low being so far away from the
region, lingering upper troughing is keeping cloud cover locked in
place. 08z/2am IR satellite imagery shows low clouds covering all
of central/northern Illinois and as far west as eastern Iowa.
Timing tools are indicating only a very slow eastward progression of
the clearing line, so have delayed the clearing across the KILX CWA
accordingly. The day will start out overcast across the board, then
a slow west-to-east clearing will occur as the day progresses.
Based on latest satellite loop and 00z forecast soundings, think
locations along/northeast of a Bloomington to Mattoon line will
remain cloudy for the entire day. Further west and south, skies
will become partly to mostly sunny this afternoon. Will be a cold
day with highs only in the 30s, but it will not be nearly as windy
as yesterday with westerly winds generally around 10 mph.
&&
.LONG TERM...(Tonight through Monday)
ISSUED AT 312 AM CST TUE NOV 25 2014
Main weather challenge in the extended continues to be clipper
system expected to track through the region on Wednesday. 00z Nov
25 models are in excellent agreement with the timing and track of
the system, but display minor differences with their QPF fields.
All models take low pressure currently over Alberta and track it
southeastward into western Iowa by 12z Wed, then into southern
Illinois by 00z Thu. This represents a continued southerly trend
in the track, which means portions of the far N/NE CWA may see
little or no precip with this system. NAM is the most
concentrated with its QPF, keeping it confined very near the low
track. Meanwhile, both the GFS and ECMWF are more generous and
spread light precip further north across the entire area. Have
updated Wednesday precip chances to focus likely PoPs along/south
of a Rushville to Decatur to Robinson line, tapering down to low
chance northeast of I-74. Given the more southerly track, WAA
ahead of the wave will be weaker than previously thought, so high
temps will not be quite as warm. Afternoon readings will range
from the middle 30s far north to the lower 40s south of I-70.
Forecast soundings support snow: however, surface temps will be
warm enough for a rain/snow mix across much of the area and
perhaps mainly rain across the far southeast. Snowfall amounts
will be mitigated by the marginal temps and overall light QPF,
with perhaps a half inch along/southwest of Macomb to Springfield
line where the precip will begin during the morning hours when it
is still cold enough to support all snow reaching the ground.
System will quickly track into the Appalachians Wednesday night,
with just a few lingering snow-showers across the E/SE into the
evening.
Once Wednesday clipper departs, the remainder of the extended
appears to be quiet. A shot of cold air behind the system will drop
high temps into the upper 20s/lower 30s on Thursday: however, a
marked warming trend is still expected for the end of the week as
eastern CONUS upper troughing relaxes and a zonal pattern develops.
As southerly winds develop on the back side of departing high
pressure, high temperatures will soar well into the 50s on Saturday
before a cold front sags southward into the region late in the day.
Still some discrepancies further out concerning how far south front
will make it, with overall consensus taking it into the Ohio River
Valley by Sunday. High pressure initially along the Gulf Coast will
limit northward moisture return, so showers will likely not develop
along/ahead of the boundary until it sinks into the SE CWA Sunday
afternoon/night. All model solutions point to a cool/dry day on
Monday before southerly flow resumes and precip chances slowly begin
to increase by Tuesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1124 AM CST TUE NOV 25 2014
Main forecast concern is with the timing of the MVFR conditions
this afternoon. All TAF sites currently with ceilings at or below
2000 feet. Clearing line advancing eastward from far western
Illinois, with AWIPS timing tool showing it reaching KSPI around
20Z, but not reaching KCMI until toward 00-01Z. Once skies clear,
VFR conditions are on tap the remainder of the forecast period.
There will be lowering ceilings late Wednesday morning ahead of a
fast moving storm system, but any MVFR conditions would likely be
after 18Z. Westerly winds this afternoon will become light and
variable for a time early this evening, before a southeast flow
sets up and persists the remainder of the forecast period.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart/EJL
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Geelhart/EJL
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1158 PM CST MON NOV 24 2014
.UPDATE...
830 PM CST
MINOR ADDITIONAL TWEAKS TO GOING FORECAST TONIGHT...MAINLY TO
REFINE POPS FOR ADDITIONAL SCATTERED SNOW SHOWERS/FLURRIES
OVERNIGHT AND TO LOWER TEMPS A BIT WITH PERSISTENT COLD ADVECTION.
REPORTS OF FREEZING DRIZZLE HAVE TAPERED OFF AT MID-EVENING AS
ANTICIPATED PER FORECAST SOUNDING TRENDS. A COMPARISON OF ILX/DVN
00Z RAOBS SHOWS THE MINOR DIFFERENCE IN LOW LEVEL SATURATION DEPTH
WITH THE TOP OF THE ILX MOIST LAYER JUST BELOW 700 HPA AND -14C
WHILE AT DVN IT IS AT 650 HPA AND -18C AND THUS MORE LIKELY TO
CONTAIN ICE AND PRODUCE SNOW. RAP SOUNDING AND IR SATELLITE
TRENDS INDICATE THAT FREEZING DRIZZLE SHOULD BE LESS OF AN ISSUE
FOR REMAINDER OF THE EVENING AS THE COLUMN CONTINUES TO COOL AND
MOISTURE DEEPENS AGAIN WITH APPROACH OF SHORT WAVE APPROACHING
FROM NORTHEAST IA. THIS WAVE IS EXPECTED TO CONTINUE TO PRODUCE
SCATTERED SNOW SHOWERS AS IT MOVES INTO THE CWA OVERNIGHT...THOUGH
HRRR/NAM BOTH INDICATE A DECREASE IN COVERAGE AFTER MIDNIGHT OVER
OUR NORTHERN CWA. THUS WHILE FLURRIES/SNOW SHOWERS WILL BE AROUND
THROUGH MUCH OF THE NIGHT...IT APPEARS THAT ANY LIGHT ADDITIONAL
MEASURABLE SNOW (JUST A COUPLE TENTHS PERHAPS) WILL BE LIMITED TO
NORTHERN PARTS OF NORTH CENTRAL IL. SNOW SHOWERS SHOULD TAPER OFF
TO JUST FLURRIES AFTER 07-09Z (2-4 AM CST) WITH PASSAGE OF
NORTHEAST IA VORT...BASED ON EXTRAPOLATION OF RADAR LOOP.
OTHERWISE...HAVE LOWERED MIN TEMPS JUST A BIT OVERNIGHT AS WE WERE
ALREADY WITHIN A COUPLE OF DEGREES OF FORECAST MINS OUT WEST.
BLENDED IN A BIT OF MAV/MET MOS GUIDANCE WHICH LOWERED MINS ABOUT
2 DEGREES IN MANY PLACES. WINDS CONTINUE TO GUST ABOVE 35 MPH IN A
FEW SPOTS...BUT WILL GRADUALLY DIMINISH OVERNIGHT AS GRADIENT
SLOWLY WEAKENS AND SURFACE PRESSURE RISE MAXIMA CONTINUES TO EXIT
TO OUR NORTHEAST.
RATZER
&&
.SHORT TERM...
302 PM CST
THROUGH WEDNESDAY...
TONIGHT...
PRIMARY SNOW BAND/DEFORMATION AXIS HAS SHIFTED NORTH BUT
WILL STILL SEE OCCASIONAL SNOW SHOWERS MOVING INTO NORTHERN ILLINOIS
INTO THE EVENING RUSH. SOME OF THESE COULD DROP VISIBILITY DOWN
UNDER 1 MILE AT TIMES...ESPECIALLY AS WINDS CONTINUE TO GUST CLOSE
TO 45 MPH AT TIMES. GOING TO SHIFT END TIME OF ADVISORY FOR
NORTH/NW CWA TO 00Z...WITH THE WIDESPREAD ACCUMULATING SNOW
ALREADY HAVING ENDED. COULD SEE SOME LINGERING LIGHT
SNOW/FLURRIES LATE EVE/OVERNIGHT AS ADDITIONAL UPPER LEVEL ENERGY
TRAVERSES AREA IN CYCLONIC FLOW ALOFT. STRATUS DECK WILL
COUNTERACT LOW LEVEL CAA TO KEEP TEMP FALL IN CHECK TONIGHT...BUT
STILL ANTICIPATING LOW- MID 20S BY DAYBREAK TUESDAY.
TUESDAY/TUES NIGHT...
OTHER THAN POSSIBLY A FEW FLURRIES IN NORTHEAST
IL/NW IN IN THE AM AS SOME LIFT REMAINS OVER THE AREA...LAKE EFFECT
FOCUS WILL LIKELY BE TO OUR EAST WITH WESTERLY FLOW. QUESTION IS
DOES STRATUS ERODE DURING AFTERNOON INTO EVENING. AS IS
TYPICAL...WRF/NAM GUIDANCE IS MOST BULLISH ON LOW LEVEL
MOISTURE...WHILE REMAINDER OF GUIDANCE DOES ENABLE DRY AIR TO MOVE
IN LATE DAY INTO TUESDAY EVENING. CONFIDENCE IS NOT THE
HIGHEST...BUT HAVE TRENDED A BIT MORE OPTIMISTIC WITH CLOUD COVER.
WARM ADVECTION WILL RAMP UP ALOFT IN ADVANCE OF CLIPPER SYSTEM
TOMORROW NIGHT...BUT WITH A TRANSIENT SURFACE RIDGE OVER THE
AREA...CLEAR/PCLOUDY SKIES COULD ENABLE A MORE SIGNIFICANT
TEMPERATURE FALL FROM HIGHS IN THE UPPER 20S-LOW 30S. THIS IS
PARTICULARLY THE CASE FOR AREAS THAT PUT DOWN SNOW COVER TODAY. HAVE
ADJUSTED LOW TEMPS DOWN A FEW DEGREES...TO UPPER TEENS IN NORTHWEST
TO LOW-MID 20S ELSEWHERE.
WEDNESDAY...
DECIDED TREND ON GUIDANCE AND ENSEMBLES TODAY HAS BEEN TO TRACK
CLIPPER MAINLY SOUTH OF THE CWA...AND HAVE ADJUSTED POPS DOWNWARD
CHANCE SOUTHWEST CWA AND SLIGHT CHANCE ELSEWHERE. UPPER LEVEL ENERGY
ASSOCIATED WITH THIS SYSTEM WAS STILL OFF OF THE BRITISH COLUMBIA
COAST AT RAOB TIME. GIVEN TENDENCY FOR LARGE SHIFTS IN THE SHORT
TERM GUIDANCE WITH THE TRACK OF SUBTLE FEATURES SUCH AS
CLIPPERS...HAVE NOT GONE WITH A COMPLETELY DRY FORECAST YET.
HOWEVER...IF TRENDS CONTINUE...ONLY THE FAR SOUTHWEST CWA WOULD SEE
ANY SENSIBLE WX IMPACTS. TEMPS LOOK TO RISE INTO THE LOW-MID
30S...WITH A FEW DEGREES ABOVE THIS POSSIBLE IF CLIPPER TRACKS
COMPLETELY SOUTH OF THE CWA. THIS WILL BE IN ADVANCE OF NEXT SURGE
OF MODIFIED ARCTIC AIR FOR THANKSGIVING DAY.
RC
&&
.LONG TERM...
WEDNESDAY NIGHT THROUGH TUESDAY...
A SECONDARY TROUGH AXIS WILL CROSS THE REGION WEDNESDAY NIGHT...BUT
OUTSIDE OF BULLISH CANADIAN MODEL...LITTLE SUPPORT FOR ANYTHING MORE
THAN SLIGHT POPS. BIG STORY IS GLANCING BLOW OF ARCTIC AIR SENDING
H85 TEMPS INTO THE LOW-MID MINUS TEENS CELSIUS ON THANKSGIVING
DAY...ONLY SUPPORTING HIGHS FROM THE MID 20S TO LOWER 30S...COLDEST
WHERE THERE WILL STILL BE SOME LEFTOVER SNOW COVER. LAKE EFFECT
FOCUS LOOKS TO BE EAST OF OUR NW IN COUNTIES...BUT WILL STILL NEED
TO MONITOR DUE TO FAVORABLE PARAMETERS.
UPPER LEVEL PATTERN CONTINUES TO LOOK TO QUICKLY SHIFT TO MORE ZONAL
ON LATEST GUIDANCE...SUPPORTING A RAPID MODERATING TREND. PRIOR TO
THAT...GUIDANCE DOES BREAK OUT SOME LIGHT WAA PRECIP ON FRIDAY AS AN
UPPER LEVEL WAVE MOVES OVER THE REGION. BETTER FORCING LOOKS TO BE
INTO SOUTHERN WI AT THIS TIME...BUT STILL A WAYS OUT. HAVE INDICATED
SLIGHT POPS FOR LIGHT SNOW...WITH A MIX OR TRANSITION TO RAIN BY
AFTERNOON FOR PARTS OF AREA AS BOUNDARY LAYER WARMS ABOVE FREEZING.
LOW PRESSURE OVER NORTHERN PLAINS LOOKS TO ADVECT IN A MUCH WARMER
AIR MASS ON SOUTHWEST FLOW ON SATURDAY. H85 TEMPS WARMING TO
POSSIBLY UPWARDS OF +10C COULD SPELL READINGS WELL INTO THE 50S (!)
FOR AT LEAST PORTIONS OF AREA IF TRENDS HOLD. DESPITE FLOW REMAINING
ZONAL...SIGNS THAT COLD AIR OVER CANADA AND FAR NORTHERN TIER COULD
TRY TO OOZE SOUTH LATER INTO THE WEEKEND INTO EARLY NEXT WEEK. THIS
WOULD SET UP A BAROCLINIC ZONE AND POSSIBLY LOW PRECIP CHANCES
RETURNING.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* PERSISTENT SCATTERED LIGHT SNOW SHOWERS...BUT REMAINING VFR.
* POTENTIAL FOR A STRONGER SNOW SHOWER EARLY THIS FORECAST
PERIOD...WITH POSSIBLE IFR VIS.
* MVFR CEILINGS THROUGH LATE MORNING.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
LATEST RADAR IMAGERY SHOWING SNOW SHOWERS PERSISTING AROUND THE
TERMINALS THIS HOUR...BUT WITH NO REAL VIS RESTRICTION. THESE SNOW
SHOWERS AND VIS TRENDS WILL CONTINUE EARLY THIS MORNING BUT WITH
THE POSSIBILITY FOR A BRIER HEAVIER SNOW SHOWER EARLY...POSSIBLY
PROVIDING IFR VIS. HAVE MAINTAINED TEMPO GROUP WITH 2SM VIS BUT
DID PUSH IT BACK AN HOUR BASED ON LATEST TRENDS. ANY SNOW WILL
LIKELY COME TO AN END LATER THIS MORNING WHILE MVFR CEILINGS
SLOWLY LIFT TO VFR BY LATE MORNING...WITH VFR CEILINGS THEN
LINGERING INTO THE AFTERNOON. AS HIGH PRESSURE BUILDS ACROSS THE
REGION THIS AFTERNOON SHOULD SEE THESE CLOUDS SCATTER...WITH ONLY
HIGH LEVEL CLOUD THEN ANTICIPATED THROUGH THE REST OF THE FORECAST
PERIOD. THE STRONGER WESTERLY WINDS ARE CURRENTLY
DIMINISHING...WITH THIS TREND CONTINUING THROUGH THE REST OF THE
MORNING BUT WHILE STAYING WESTERLY.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE WITH SCATTERED LIGHT SNOW SHOWERS.
* MEDIUM CONFIDENCE WITH ANY STRONGER SNOW SHOWERS EARLY.
* HIGH CONFIDENCE WITH MVFR CEILINGS...LOW MEDIUM CONFIDENCE WITH
DURATION.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...SCHC SNOW. OTHERWISE VFR. SOUTHEAST TO EAST WINDS.
THURSDAY...A FEW FLURRIES POSSIBLE...OTHERWISE VFR. BREEZY NORTHWEST WINDS.
FRIDAY...SCHC SNOW. SOUTH WINDS.
SATURDAY...VFR. WEST-SOUTHWEST WINDS.
SUNDAY...VFR. NORTH WINDS.
MDB
&&
.MARINE...
235 PM CST
LOW PRESSURE THAT MOVED OVER THE STRAITS THIS MORNING AND DRAGGED A
COLD FRONT ACROSS THE LAKE WILL HAVE LIFTED INTO THE JAMES BAY AREA
LATE THIS EVENING. STRONG WEST GALES ACROSS THE SOUTH HALF OF THE
LAKE WILL PERSIST INTO THE OVERNIGHT HOURS...WITH GUSTY BUT WEAKER
NORTHWEST WINDS ACROSS THE NORTHERN HALF OF THE LAKE. SNOW MOVES
OUT TONIGHT EXCEPT FOR LINGERING LAKE EFFECT ALONG THE MICHIGAN
SHORE.
WINDS REMAIN WESTERLY BUT RELAX DURING THE DAY TUESDAY AND THEN
RELAX FURTHER BY WEDNESDAY IN A WEAK AND DISORGANIZED PRESSURE
GRADIENT. BY WEDNESDAY NIGHT INTO THURSDAY THE PATTERN BECOMES
BETTER ORGANIZED AGAIN AND WINDS PICK UP FROM THE WEST TO NORTH.
WEATHER REMAINS MOSTLY QUIET THIS WEEK AFTER TONIGHT ASIDE FROM A
BRIEF SHOT OF SNOW AGAIN LATE WEDNESDAY AND THE MICHIGAN SIDE LAKE
EFFECT.
LENNING
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ740-LMZ741-
LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ870-LMZ872-
LMZ874-LMZ876-LMZ878 UNTIL 3 AM TUESDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
615 PM MST WED NOV 26 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 123 PM MST WED NOV 26 2014
AS OF 2 PM CST...1 PM MST...SKIES ACROSS THE TRI-STATE REGION VARIED
FROM MOSTLY CLEAR TO OVERCAST. TEMPERATURES WERE IN THE 40S WHERE
CLOUDS HAVE BROKEN UP AND IN THE LOW TO UPPER 30S WHERE PERSISTENT
CLOUDS REMAIN. WINDS WERE FROM THE NORTH AT 10 TO 15 MPH AND ON A
GRADUAL WEAKENING TREND. WSR-88D RADAR DATA HAS NOTED A DOWNWARD
TREND IN RADAR REFLECTIVITIES AS THE BAND OF LIGHT SNOW SHOWERS
FINALLY BEGINS TO DIMINISH. SNOW APPEARS TO BE THE RESULT OF LOW
LEVEL FRONTOGENESIS OVER NORTHEAST COLORADO AS NO MAJOR DISTURBANCES
HAVE BEEN OBSERVED BY WATER VAPOR IMAGERY.
FOR THE REST OF THE AFTERNOON AND TONIGHT...MAIN FORECAST CONCERN IS
DECREASING SNOW SHOWER ACTIVITY THROUGH THE AFTERNOON WITH POSSIBLE
BRIEF REDEVELOPMENT THIS EVENING. LATEST RAP GUIDANCE/HRRR GUIDANCE
SEEMS TO BE HANDLING THIS SITUATION BEST SO HAVE LEANED ON THESE
SOLUTIONS. RAP FORECAST SOUNDINGS INDICATE THAT THE ICE CRYSTAL
GROWTH ZONE LOSES SATURATION THIS AFTERNOON...LEADING TO A DECREASE
IN PRECIPITATION. THAT TREND IS ALREADY BEING REALIZED. RAP
SOUNDINGS THEN INDICATE ONE MORE PUSH OF MOISTURE IN THE ICE CRYSTAL
GROWTH ZONE LATER THIS EVENING BEFORE THE ENTIRE ATMOSPHERIC PROFILE
DESATURATES. ATTEMPTED TO SHOW THIS UP AND DOWN TREND WITH THE POPS
THROUGH THIS EVENING AND THEN FORECAST DRY WEATHER AFTER MIDNIGHT.
SKIES GRADUALLY CLEAR LATE TONIGHT WITH A QUICK DROP IN TEMPS ONCE
CONDITIONS ARE CONDUCIVE FOR RADIATIONAL COOLING.
FOR THANKSGIVING DAY...OVERALL CALM WEATHER IS ANTICIPATED WITH NO
PRECIPITATION EXPECTED. ATMOSPHERIC PROFILE BECOMES QUITE DRY BY
AFTERNOON...ESPECIALLY IN THE LOW LEVELS...AS DRY AIR ADVECTION
CONTINUES FROM THE SOUTHWEST. A LEE TROUGH DEEPENING OVER CENTRAL
COLORADO SHALL LEAD TO PERSISTENT SOUTHWEST FLOW THROUGHOUT THE DAY.
WARM 850 MB TEMPS ALSO ADVECT IN SO EXPECTING A WARM...ABOVE NORMAL
DAY. ONE THING THAT IS INTERESTING ABOUT TOMORROW IS FORECAST
SOUNDINGS INDICATE THAT A PERSISTENT INVERSION NEAR THE SURFACE MAY
PREVENT SOME STRONGER WIND GUSTS ALOFT FROM BEING REALIZED AT THE
SURFACE. WILL NEED TO WATCH THIS CAREFULLY AS LOW RELATIVE HUMIDITY
WILL BE PRESENT OVER CHEYENNE AND KIT CARSON COUNTIES IN COLORADO
AND SHERMAN...WALLACE...GREELEY AND POSSIBLY WICHITA COUNTIES IN
KANSAS. OVERALL...KEPT FORECAST WINDS LIGHT BUT NERVOUS ABOUT
STRONGER WINDS ALOFT MIXING DOWN. IF WINDS ARE REALIZED...A FIRE
WEATHER HIGHLIGHT MAY BE REQUIRED.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 1204 PM MST WED NOV 26 2014
BROAD ZONAL FLOW WILL PERSIST THROUGH SATURDAY ACROSS THE CENTRAL
CONUS OVER A LOW AMPLITUDE RIDGE CENTERED OVER THE DESERT
SOUTHWEST. THIS WILL RESULT IN DRY CONDITIONS AND MUCH ABOVE
NORMAL TEMPERATURES. RELATIVE HUMIDITY WILL DROP TO NEAR CRITICAL
FIRE WEATHER VALUES EACH AFTERNOON...HOWEVER WIND FORECASTS ARE
RELATIVELY LIGHT AND NO FIRE WEATHER HIGHLIGHTS ARE ANTICIPATED. A
NORTHERN STREAM SHORTWAVE WILL SUPPORT A SURFACE COLD FRONT WHICH
WILL MOVE THROUGH THE CENTRAL HIGH PLAINS SATURDAY NIGHT. SYNOPTIC
SCALE FORCING FOR PRECIPITATION WILL REMAIN NORTH OF THE LOCAL
AREA AND FROPA WILL LIKELY BE DRY. TEMPERATURES ON SUNDAY WILL BE
CLOSER TO NORMAL...THEN COOL TO BELOW NORMAL ON MONDAY WHICH WILL
BE THE COLDEST DAY OF THIS PERIOD. TEMPERATURES BOUNCE BACK TO
ABOVE NORMAL ON TUESDAY UNDER SHORTWAVE RIDGING WITH CONTINUED DRY
CONDITIONS. FINALLY...ON WEDNESDAY A SHORTWAVE TROUGH IN THE
SOUTHERN STREAM WILL MOVE OUT OF THE SOUTHERN ROCKIES AND EMERGE
ONTO THE ADJACENT PLAINS...WITH A CHANCE FOR RAIN AND SNOW. TIMING
AND AMOUNTS WITH THE SYSTEM STILL VERY UNCERTAIN WITH SIGNIFICANT
MODEL DIFFERENCES AT THIS TIME RANGE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 537 PM MST WED NOV 26 2014
VFR CONDITIONS ARE EXPECTED AT BOTH MCK AND GLD THROUGH THE TAF
PERIOD WITH WINDS BECOMING LIGHT AND VARIABLE OVERNIGHT...BEFORE
TURNING TO THE SOUTHWEST AT GLD AND SOUTH AT MCK AS HIGH PRESSURE
MOVES OFF TO THE EAST AND A LEE SURFACE TROUGH DEEPENS ALONG THE
FRONT RANGE DURING THE DAY ON THURSDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...RRH
LONG TERM...024
AVIATION...LOCKHART
AREA FORECAST DISCUSSION
NWS JACKSON KY
1105 PM EST WED NOV 26 2014
.UPDATE...
ISSUED AT 1104 PM EST WED NOV 26 2014
SEVERAL CHANGES WERE MADE BASED ON CURRENT CONDITIONS AND TRENDS.
FIRST...THE POPS. OVERALL...THE RAINFALL COVERAGE SEEMS TO MATCH UP
WELL WITH THE ONGOING FORECAST FOR POPS. HOWEVER...THE COVERAGE OF
THIS SYSTEM HAS NOT REACHED AS FAR NORTH AS WAS ORIGINALLY EXPECTED.
AS A RESULT...TONED BACK SOME OF OUR SLIGHT CHANCE POPS ACROSS THE
NORTHERN CWA FOR THE NEXT COUPLE OF HOURS. ONCE MORE PRECIP MOVES
INTO THE AREA...ALLOWED FOR SOME SLIGHT CHANCES TO EXPAND ACROSS THE
REMAINDER OF THE CWA.
ALSO...LOOKING AT THE ONGOING FORECASTED DIURNAL CURVE FOR THE
REMAINDER OF THE NIGHT...IT SHOWED TEMPS RISING ACROSS PORTIONS OF
THE FAR EASTERN CWA OVER THE NEXT FEW HOURS...BEFORE DROPPING NEAR
DAWN. MEANWHILE...CURRENT OBSERVATIONS ARE SHOWING TEMPERATURES
EITHER REMAINING STEADY OR DROPPING ACROSS THE CWA. THIS WAS CREATING
SOME DISCREPANCIES IN THE NEAR TERM TEMPERATURE FORECAST...AND WOULD
CONTINUE TO DO SO THROUGHOUT THE NIGHT...EVEN WHEN BLENDING IN THE
LATEST NEAR TERM OBSERVATIONS. ENDED UP ADJUSTING THE DIURNAL CURVE
FOR A MORE STEADY DOWNWARD TREND THROUGHOUT THE NIGHT.
AS SUCH...THIS CHANGED THE WEATHER TYPES SOMEWHAT THROUGHOUT THE
NIGHT. ULTIMATELY IT ALLOWED FOR BETTER MATCHING UP WITH NEIGHBORING
OFFICES FOR CHANGE OVER FROM RAIN TO SNOW. BUT GIVEN THE LIGHT NATURE
OF THIS SYSTEM SO FAR...AND THE FACT THAT MUCH OF THIS SNOW WILL MIX
WITH RAIN THROUGH THE MAJORITY OF THE NIGHT...FELT THAT SNOW TOTALS
ULTIMATELY SEEMED REASONABLE AND DID NOT NEED TO BE CHANGED. STILL
EXPECTING BEST SNOW ACCUMULATIONS AROUND DAWN WHEN TEMPS ARE THE
COLDEST. BUT AT THIS POINT THE SYSTEM WILL BE DYING DOWN AND MOVING
OUT...AND DAYTIME TEMPS WILL WORK TO QUICKLY MELT ANYTHING THAT HAS
ACCUMULATED.
UPDATE ISSUED AT 655 PM EST WED NOV 26 2014
BASED ON THE LATEST SATELLITE DATA...WENT AHEAD AND INCREASED CLOUD
COVER ACROSS THE CWA...WITH CLOUDS EXPECTED TO CONTINUE THICKENING
THROUGHOUT THE EVENING AND OVERNIGHT. SOME OF THESE CLOUDS ARE
HIGH...BUT ARE COVERING A LARGE MAJORITY OF THE CWA...SO WENT AHEAD
AND INCLUDED BKN CLOUDS FOR THE REST OF THE EVENING.
CURRENTLY...TEMPERATURE READINGS ARE STILL IN THE UPPER 30S AND LOW
40S...WITH DEW POINT DEPRESSIONS 10 TO 20 DEGREES. ALTHOUGH WE ARE
GETTING A FEW RADAR RETURNS IN THE FAR SW PORTION OF THE CWA...IT IS
UNLIKELY THAT ANY OF THIS MOISTURE WILL MAKE IT TO THE SURFACE FOR AT
LEAST A FEW MORE HOURS. AND GIVEN THE CURRENT TEMPERATURES...ONCE
PRECIP DOES FALL...IT SHOULD BE IN THE FORM OF RAIN. LATEST FORECAST
SOUNDINGS FOR BOTH THE NAM AND GFS ARE STILL SHOWING TEMPERATURES
REMAINING ABOVE FREEZING THROUGH AT LEAST 6Z...IF NOT LONGER IN SOME
LOCATIONS...AND THEN HOVERING RIGHT AROUND THE FREEZING MARK
THEREAFTER UNTIL WARMING AGAIN AFTER DAY BREAK. HOWEVER...ACCORDING
TO THE LATEST WPC WINTER WEATHER ACCUMULATION FORECAST ISSUED AROUND
1630Z...2 TO 4 INCHES IS STILL EXPECTED IN THE SOUTHERN PORTION OF
THE CWA. IN OTHER WORDS...SOME GOOD WET BULBING PROCESSES ARE GOING
TO HAVE TO TAKE PLACE THIS EVENING IN ORDER FOR THIS TO PAN OUT. AS
SUCH...THERE HASN/T BEEN ENOUGH EVIDENCE TO CHANGE THE CURRENT
FORECAST SNOW TOTALS. STILL EXPECT WHAT DOES FALL TO MAINLY
ACCUMULATE ON THE GRASSY AND ELEVATED SURFACES...AND TURN INTO A
SLUSHY MIX OF RAIN AND SNOW ON THE ROADWAYS BEFORE QUICKLY MELTING
OFF.
WILL CONTINUE TO MONITOR TEMPS AND PRECIPITATION UPSTREAM AS THIS
SYSTEM NEARS AND BEGINS IMPACTING THE REGION...IN CASE ANY
MODIFICATIONS TO THE CURRENT SNOW/RAIN FORECAST NEED TO BE MADE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 315 PM EST WED NOV 26 2014
...SOME SLUSHY SNOW ACCUMULATIONS POSSIBLE LATE TONIGHT OVER SOUTHERN
PARTS OF EAST KENTUCKY...
19Z SFC ANALYSIS SHOWS EAST KENTUCKY IN BETWEEN TWO AREAS OF LOW
PRESSURE. TO THE EAST...A COASTAL LOW IS NOW PASSING NORTH OF CAPE
HATTERAS...WHILE A MORE MODERATE STRENGTH SFC LOW IS LOCATED OVER
CENTRAL MISSOURI ON ITS PATH SOUTHEAST INTO THE TENNESSEE VALLEY. IN
THE GAP BETWEEN THESE SYSTEMS ENOUGH CLEARING TOOK PLACE FOR MOST OF
THE AREA THAT TEMPERATURES CLIMBED INTO UPPER 40S AND LOWER 50S THIS
AFTERNOON. WINDS ARE GENERALLY LIGHT WHILE DEWPOINTS ARE FOUND IN THE
MID AND UPPER 20S...THOUGH WITH SOME 30S IN THE FAR EAST.
THE MODELS ARE IN PRETTY GOOD AGREEMENT...NOW THAT THE GFS IS
BREAKING TOWARD THE ECMWF AND NAM...ALOFT WITH THE CLIPPER SYSTEM
DROPPING INTO THE TENNESSEE VALLEY TONIGHT. THEY ALL SHOW THE
ENERGY...ASSOCIATED WITH EASTERN PORTION OF THE LARGE TROUGH IN
PLACE OVER THE OHIO VALLEY...LIFTING NORTHEAST INTO EASTERN NEW
ENGLAND BY THURSDAY MORNING. AT THE SAME TIME...A SECONDARY BATCH OF
ENERGY WITHIN THE LARGER TROUGH WILL RIDE SOUTHEAST FROM THE EAST
CENTRAL PLAINS TO THE TENNESSEE VALLEY...THOUGH SHEARING AS IT PASSES
BY KENTUCKY TO THE SOUTH TONIGHT. FOLLOWING THIS...THE WHOLE TROUGH
BODILY MOVES OUT OF THE REGION AND RISING HEIGHTS FOLLOW. HAVE
FOLLOWED A GENERAL MODEL BLEND FOR THE SHORT TERM PORTION THE
FORECAST WITH SOME CAUTIOUS FAVORING OF THE HIGHER RESOLUTION NAM12
AND HRRR FOR WX DETAILS.
SENSIBLE WEATHER WILL FEATURE A QUIET EVENING AS HIGH CLOUDS OVERTAKE
THE SKY AND LOWER WITH TIME. A WEAKENING AREA OF LOW PRESSURE WILL
SLIDE SOUTH THROUGH SOUTHERN KENTUCKY AND INTO EASTERN TENNESSEE.
THIS WILL BRING WITH IT A NARROW BAND OF PCPN CAPABLE OF BECOMING
SNOW GIVEN THE EXPECTED WETBULB EFFECT WHEN IT STARTS COMING DOWN
MODERATELY ACROSS OUR SOUTHERN COUNTIES. HOWEVER...SFC TEMPERATURES
WILL BE NEAR 32 DEGREES AT THEIR COLDEST LIKELY PREVENTING MUCH
ACCUMULATION ON ANYTHING MORE THAN GRASSY AND ELEVATED SURFACES AND
THEN MAINLY ON THE RIDGES AS THE VALLEYS REMAIN A MIX OF RAIN AND
SNOW. THIS IS A DISTURBINGLY SIMILAR SITUATION AS COMPARED TO LAST
NIGHT IN THE EAST WHERE THE HEAVIER PCPN STAYED JUST OFF TO THE EAST.
THESE SMALL SCALE DETAILS MAKE ALL THE DIFFERENCE IN MARGINAL
SITUATIONS AS THIS. HOWEVER...CANNOT RULE OUT A HEAVIER BURST OR TWO
OF SNOW THAT COULD CAUSE A SLUSHY ACCUMULATION ON THE ROADS. THIS
SHOULD NOT LAST LONG...THOUGH...AS ROAD TEMPERATURES ARE CURRENTLY IN
THE 40S AND 50S AND WILL ONLY SLOWLY FALL WITH THE PCPN TONIGHT. HAVE
ISSUED AN SPS TO DEAL WITH THE POTENTIAL FOR A SLUSHY INCH OF SNOW
THAT SHOULD HAVE A MINIMAL IMPACT ON TRAVELERS TONIGHT. THE LIGHT
SNOW/RAIN PULLS OUT OF THE AREA EARLY THURSDAY WITH COOLER
TEMPERATURES TO FOLLOW AS HIGH PRESSURE MOVES THROUGH THE SOUTHERN
APPALACHIANS INTO FRIDAY MORNING.
ONCE AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR T/TD/WINDS
THROUGH THE NEXT 24 HOURS AND THE SUPERBLEND THEREAFTER. DID MAKE
SOME TERRAIN BASED ADJUSTMENTS TONIGHT INTO THURSDAY MAINLY TO LOWER
THE RIDGES IN OUR SOUTHERN COUNTIES DUE TO THE PCPN AND ANTICIPATED
WETBULBING. AS FOR POPS...ENDED UP CLOSE TO A BLEND OF THE DRIER MAV
AND WETTER MET NUMBERS TONIGHT INTO THURSDAY MORNING AND THEN
MATCHED THEIR DRY CONSENSUS INTO FRIDAY MORNING.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 245 PM EST WED NOV 26 2014
THE SYNOPTIC PATTERN THROUGH THE LONG TERM PERIOD WILL FEATURE A
PROGRESSIVE FLOW ALOFT WITH A GENERAL SOUTHWEST FLOW IN THE LOW
LEVELS AS AN ELONGATED AREA OF SURFACE HIGH PRESSURE STRETCHES OUT
FROM THE DEEP SOUTH EASTWARD INTO THE WESTERN ATLANTIC. A COLD FRONT
WILL DROP SOUTH INTO THE REGION ON MONDAY...AND THEN STALL OUT IN
OUR VICINITY AS THE SPONSORING UPPER TROUGH PASSES BY TO THE NORTH.
A SECOND TROUGH WILL THEN FOLLOW A SIMILAR TRACK AND PASS BY TO OUR
NORTH MIDWEEK. FORECAST MODELS DIFFER ON THE STRENGTH OF THIS
SHORTWAVE AND THE RESULTING IMPACT IT WILL HAVE ON THE FRONT
AND FORECASTER CONFIDENCE DROPS BELOW AVERAGE BY THE END OF THE
PERIOD.
OUR SENSIBLE WEATHER WILL FEATURE A MODERATING TREND OVER THE
THANKSGIVING HOLIDAY WEEKEND. UNFORTUNATELY...THE WARMING TEMPS WILL
BE ACCOMPANIED BY INCREASING CLOUDS AND A FEW SHOWERS BY SATURDAY
NIGHT INTO THE DAY ON SUNDAY AS LOW LEVEL MOISTURE INCREASES. RAIN
CHANCES THEN INCREASE DRAMATICALLY SUNDAY NIGHT INTO MONDAY AS THE
FRONT DROPS INTO THE AREA. BEYOND MONDAY...TEMPS AND RAIN CHANCES
ARE PROBLEMATIC DUE TO THE MODEL DIFFERENCES REGARDING THE PLACEMENT
OF THE FRONT. SIDING WITH A MODEL BLEND YIELDS NEAR NORMAL TEMPS AND
A CHANCE OF RAIN EACH PERIOD THROUGH WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 656 PM EST WED NOV 26 2014
VFR CONDITIONS WILL PREVAIL THROUGH THE AREA INTO THE EVENING BEFORE
THE CIGS START TO DROP...PARTICULARLY AT THE SOUTHERN SITES. EXPECT
AN AREA OF RAIN AND SNOW TO SLIDE THROUGH THE CUMBERLAND VALLEY
OVERNIGHT WITH A GOOD CHANCE OF DROPPING VIS AND CIGS INTO THE MVFR
AND IFR RANGES AS THE SNOW DEVELOPS AND PASSES THROUGH. THE SME AND
LOZ SITES WILL LIKELY SEE THE WORST CONDITIONS...THOUGH IF THE PCPN
IS NOT ABLE TO WET BULB TO SNOW EFFECTIVELY...AT LEAST THE VIS WILL
NOT BE AS LOW AS CURRENTLY FORECASTED. EXPECT THE CONDITIONS TO
GRADUALLY IMPROVE THROUGH THE DAY THURSDAY ONCE THIS WAVE PASSES...
BUT CIGS WILL PROBABLY BE MVFR AT MOST SITES THROUGH THE MORNING.
WINDS WILL BE LIGHT AND VARIABLE THROUGH THE NIGHT BEFORE PICKING UP
A BIT FROM THE NORTHWEST INTO THE MORNING IN THE WAKE OF THE SFC LOW.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...ABE
AVIATION...GREIF/JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
656 PM EST WED NOV 26 2014
.UPDATE...
ISSUED AT 655 PM EST WED NOV 26 2014
BASED ON THE LATEST SATELLITE DATA...WENT AHEAD AND INCREASED CLOUD
COVER ACROSS THE CWA...WITH CLOUDS EXPECTED TO CONTINUE THICKENING
THROUGHOUT THE EVENING AND OVERNIGHT. SOME OF THESE CLOUDS ARE
HIGH...BUT ARE COVERING A LARGE MAJORITY OF THE CWA...SO WENT AHEAD
AND INCLUDED BKN CLOUDS FOR THE REST OF THE EVENING.
CURRENTLY...TEMPERATURE READINGS ARE STILL IN THE UPPER 30S AND LOW
40S...WITH DEW POINT DEPRESSIONS 10 TO 20 DEGREES. ALTHOUGH WE ARE
GETTING A FEW RADAR RETURNS IN THE FAR SW PORTION OF THE CWA...IT IS
UNLIKELY THAT ANY OF THIS MOISTURE WILL MAKE IT TO THE SURFACE FOR AT
LEAST A FEW MORE HOURS. AND GIVEN THE CURRENT TEMPERATURES...ONCE
PRECIP DOES FALL...IT SHOULD BE IN THE FORM OF RAIN. LATEST FORECAST
SOUNDINGS FOR BOTH THE NAM AND GFS ARE STILL SHOWING TEMPERATURES
REMAINING ABOVE FREEZING THROUGH AT LEAST 6Z...IF NOT LONGER IN SOME
LOCATIONS...AND THEN HOVERING RIGHT AROUND THE FREEZING MARK
THEREAFTER UNTIL WARMING AGAIN AFTER DAY BREAK. HOWEVER...ACCORDING
TO THE LATEST WPC WINTER WEATHER ACCUMULATION FORECAST ISSUED AROUND
1630Z...2 TO 4 INCHES IS STILL EXPECTED IN THE SOUTHERN PORTION OF
THE CWA. IN OTHER WORDS...SOME GOOD WET BULBING PROCESSES ARE GOING
TO HAVE TO TAKE PLACE THIS EVENING IN ORDER FOR THIS TO PAN OUT. AS
SUCH...THERE HASN/T BEEN ENOUGH EVIDENCE TO CHANGE THE CURRENT
FORECAST SNOW TOTALS. STILL EXPECT WHAT DOES FALL TO MAINLY
ACCUMULATE ON THE GRASSY AND ELEVATED SURFACES...AND TURN INTO A
SLUSHY MIX OF RAIN AND SNOW ON THE ROADWAYS BEFORE QUICKLY MELTING
OFF.
WILL CONTINUE TO MONITOR TEMPS AND PRECIPITATION UPSTREAM AS THIS
SYSTEM NEARS AND BEGINS IMPACTING THE REGION...IN CASE ANY
MODIFICATIONS TO THE CURRENT SNOW/RAIN FORECAST NEED TO BE MADE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 315 PM EST WED NOV 26 2014
...SOME SLUSHY SNOW ACCUMULATIONS POSSIBLE LATE TONIGHT OVER SOUTHERN
PARTS OF EAST KENTUCKY...
19Z SFC ANALYSIS SHOWS EAST KENTUCKY IN BETWEEN TWO AREAS OF LOW
PRESSURE. TO THE EAST...A COASTAL LOW IS NOW PASSING NORTH OF CAPE
HATTERAS...WHILE A MORE MODERATE STRENGTH SFC LOW IS LOCATED OVER
CENTRAL MISSOURI ON ITS PATH SOUTHEAST INTO THE TENNESSEE VALLEY. IN
THE GAP BETWEEN THESE SYSTEMS ENOUGH CLEARING TOOK PLACE FOR MOST OF
THE AREA THAT TEMPERATURES CLIMBED INTO UPPER 40S AND LOWER 50S THIS
AFTERNOON. WINDS ARE GENERALLY LIGHT WHILE DEWPOINTS ARE FOUND IN THE
MID AND UPPER 20S...THOUGH WITH SOME 30S IN THE FAR EAST.
THE MODELS ARE IN PRETTY GOOD AGREEMENT...NOW THAT THE GFS IS
BREAKING TOWARD THE ECMWF AND NAM...ALOFT WITH THE CLIPPER SYSTEM
DROPPING INTO THE TENNESSEE VALLEY TONIGHT. THEY ALL SHOW THE
ENERGY...ASSOCIATED WITH EASTERN PORTION OF THE LARGE TROUGH IN
PLACE OVER THE OHIO VALLEY...LIFTING NORTHEAST INTO EASTERN NEW
ENGLAND BY THURSDAY MORNING. AT THE SAME TIME...A SECONDARY BATCH OF
ENERGY WITHIN THE LARGER TROUGH WILL RIDE SOUTHEAST FROM THE EAST
CENTRAL PLAINS TO THE TENNESSEE VALLEY...THOUGH SHEARING AS IT PASSES
BY KENTUCKY TO THE SOUTH TONIGHT. FOLLOWING THIS...THE WHOLE TROUGH
BODILY MOVES OUT OF THE REGION AND RISING HEIGHTS FOLLOW. HAVE
FOLLOWED A GENERAL MODEL BLEND FOR THE SHORT TERM PORTION THE
FORECAST WITH SOME CAUTIOUS FAVORING OF THE HIGHER RESOLUTION NAM12
AND HRRR FOR WX DETAILS.
SENSIBLE WEATHER WILL FEATURE A QUIET EVENING AS HIGH CLOUDS OVERTAKE
THE SKY AND LOWER WITH TIME. A WEAKENING AREA OF LOW PRESSURE WILL
SLIDE SOUTH THROUGH SOUTHERN KENTUCKY AND INTO EASTERN TENNESSEE.
THIS WILL BRING WITH IT A NARROW BAND OF PCPN CAPABLE OF BECOMING
SNOW GIVEN THE EXPECTED WETBULB EFFECT WHEN IT STARTS COMING DOWN
MODERATELY ACROSS OUR SOUTHERN COUNTIES. HOWEVER...SFC TEMPERATURES
WILL BE NEAR 32 DEGREES AT THEIR COLDEST LIKELY PREVENTING MUCH
ACCUMULATION ON ANYTHING MORE THAN GRASSY AND ELEVATED SURFACES AND
THEN MAINLY ON THE RIDGES AS THE VALLEYS REMAIN A MIX OF RAIN AND
SNOW. THIS IS A DISTURBINGLY SIMILAR SITUATION AS COMPARED TO LAST
NIGHT IN THE EAST WHERE THE HEAVIER PCPN STAYED JUST OFF TO THE EAST.
THESE SMALL SCALE DETAILS MAKE ALL THE DIFFERENCE IN MARGINAL
SITUATIONS AS THIS. HOWEVER...CANNOT RULE OUT A HEAVIER BURST OR TWO
OF SNOW THAT COULD CAUSE A SLUSHY ACCUMULATION ON THE ROADS. THIS
SHOULD NOT LAST LONG...THOUGH...AS ROAD TEMPERATURES ARE CURRENTLY IN
THE 40S AND 50S AND WILL ONLY SLOWLY FALL WITH THE PCPN TONIGHT. HAVE
ISSUED AN SPS TO DEAL WITH THE POTENTIAL FOR A SLUSHY INCH OF SNOW
THAT SHOULD HAVE A MINIMAL IMPACT ON TRAVELERS TONIGHT. THE LIGHT
SNOW/RAIN PULLS OUT OF THE AREA EARLY THURSDAY WITH COOLER
TEMPERATURES TO FOLLOW AS HIGH PRESSURE MOVES THROUGH THE SOUTHERN
APPALACHIANS INTO FRIDAY MORNING.
ONCE AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR T/TD/WINDS
THROUGH THE NEXT 24 HOURS AND THE SUPERBLEND THEREAFTER. DID MAKE
SOME TERRAIN BASED ADJUSTMENTS TONIGHT INTO THURSDAY MAINLY TO LOWER
THE RIDGES IN OUR SOUTHERN COUNTIES DUE TO THE PCPN AND ANTICIPATED
WETBULBING. AS FOR POPS...ENDED UP CLOSE TO A BLEND OF THE DRIER MAV
AND WETTER MET NUMBERS TONIGHT INTO THURSDAY MORNING AND THEN
MATCHED THEIR DRY CONSENSUS INTO FRIDAY MORNING.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 245 PM EST WED NOV 26 2014
THE SYNOPTIC PATTERN THROUGH THE LONG TERM PERIOD WILL FEATURE A
PROGRESSIVE FLOW ALOFT WITH A GENERAL SOUTHWEST FLOW IN THE LOW
LEVELS AS AN ELONGATED AREA OF SURFACE HIGH PRESSURE STRETCHES OUT
FROM THE DEEP SOUTH EASTWARD INTO THE WESTERN ATLANTIC. A COLD FRONT
WILL DROP SOUTH INTO THE REGION ON MONDAY...AND THEN STALL OUT IN
OUR VICINITY AS THE SPONSORING UPPER TROUGH PASSES BY TO THE NORTH.
A SECOND TROUGH WILL THEN FOLLOW A SIMILAR TRACK AND PASS BY TO OUR
NORTH MIDWEEK. FORECAST MODELS DIFFER ON THE STRENGTH OF THIS
SHORTWAVE AND THE RESULTING IMPACT IT WILL HAVE ON THE FRONT
AND FORECASTER CONFIDENCE DROPS BELOW AVERAGE BY THE END OF THE
PERIOD.
OUR SENSIBLE WEATHER WILL FEATURE A MODERATING TREND OVER THE
THANKSGIVING HOLIDAY WEEKEND. UNFORTUNATELY...THE WARMING TEMPS WILL
BE ACCOMPANIED BY INCREASING CLOUDS AND A FEW SHOWERS BY SATURDAY
NIGHT INTO THE DAY ON SUNDAY AS LOW LEVEL MOISTURE INCREASES. RAIN
CHANCES THEN INCREASE DRAMATICALLY SUNDAY NIGHT INTO MONDAY AS THE
FRONT DROPS INTO THE AREA. BEYOND MONDAY...TEMPS AND RAIN CHANCES
ARE PROBLEMATIC DUE TO THE MODEL DIFFERENCES REGARDING THE PLACEMENT
OF THE FRONT. SIDING WITH A MODEL BLEND YIELDS NEAR NORMAL TEMPS AND
A CHANCE OF RAIN EACH PERIOD THROUGH WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 656 PM EST WED NOV 26 2014
VFR CONDITIONS WILL PREVAIL THROUGH THE AREA INTO THE EVENING BEFORE
THE CIGS START TO DROP...PARTICULARLY AT THE SOUTHERN SITES. EXPECT
AN AREA OF RAIN AND SNOW TO SLIDE THROUGH THE CUMBERLAND VALLEY
OVERNIGHT WITH A GOOD CHANCE OF DROPPING VIS AND CIGS INTO THE MVFR
AND IFR RANGES AS THE SNOW DEVELOPS AND PASSES THROUGH. THE SME AND
LOZ SITES WILL LIKELY SEE THE WORST CONDITIONS...THOUGH IF THE PCPN
IS NOT ABLE TO WET BULB TO SNOW EFFECTIVELY...AT LEAST THE VIS WILL
NOT BE AS LOW AS CURRENTLY FORECASTED. EXPECT THE CONDITIONS TO
GRADUALLY IMPROVE THROUGH THE DAY THURSDAY ONCE THIS WAVE PASSES...
BUT CIGS WILL PROBABLY BE MVFR AT MOST SITES THROUGH THE MORNING.
WINDS WILL BE LIGHT AND VARIABLE THROUGH THE NIGHT BEFORE PICKING UP
A BIT FROM THE NORTHWEST INTO THE MORNING IN THE WAKE OF THE SFC LOW.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...ABE
AVIATION...GREIF/JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
356 PM EST TUE NOV 25 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 325 PM EST TUE NOV 25 2014
...ACCUMULATING SNOW EXPECTED OVER FAR EASTERN KENTUCKY TONIGHT INTO
WEDNESDAY MORNING...
19Z SFC ANALYSIS SHOWS HIGH PRESSURE STILL INFLUENCING THE WEATHER OF
EASTERN KENTUCKY. THIS HAS PROVIDED PLENTY OF SUNSHINE AND GENERALLY
SOUTHWEST WINDS OF 5 TO 10 KTS WITH OCCASIONAL GUSTS TO 15 KTS. THESE
CONDITIONS...ALONG WITH GOOD DRYING THROUGH EARLY AFTERNOON HAS SENT
TEMPERATURES WELL UP INTO THE 50S FOR MOST OF THE AREA...THOUGH
LOCATIONS NORTHWEST OF INTERSTATE 64 ARE LAGGING IN THE UPPER 40S. OF
NOTE ON THE SFC CHART IS AN AREA OF DEVELOPING LOW PRESSURE CROSSING
NORTHERN FLORIDA ON ITS WAY TO THE SOUTHEAST U.S. SEABOARD.
THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT THROUGH THE FIRST PART
OF THE SHORT TERM FORECAST. THEY ALL TAKE A STRONG SHORTWAVE
CURRENTLY BOTTOMING OUT OVER THE CENTRAL GULF COAST NORTHEAST INTO
THE SOUTHERN APPALACHIANS BY WEDNESDAY MORNING. IN ADDITION...A
COMPACT WAVE WILL BE DROPPING SOUTHEAST FROM THE NORTHERN PLAINS INTO
THE MID MISSISSIPPI VALLEY AND EVENTUALLY THROUGH THE TENNESSEE
VALLEY LATER WEDNESDAY NIGHT. THE MODELS ARE CLOSE ON THE TIMING OF
THIS BUT THE CORE OF THE ENERGY IS FURTHER SOUTH IN THE NAM...
ECMWF...AND GEM WHEN COMPARED TO THE GFS. WILL FAVOR THIS MORE
SOUTHERN TRACK AS SEEN IN THE CONSENSUS. IN GENERAL HAVE LEANED MOST
CLOSELY TO THE HIGHER RESOLUTION MODELS OF THE NAM12 AND HRRR...
THOUGH THE HRRR PCPN FIELDS SEEM TOO FAR SOUTHEAST AND SLOW LATER
TONIGHT.
SENSIBLE WEATHER WILL FEATURE A QUICK INCREASE IN CLOUD COVER FROM
THE SOUTHEAST AS THE COASTAL LOW STARTS TO TAKE SHAPE LATER THIS
EVENING. LOWER CLOUDS AND PCPN WILL START TO SPILL OVER THE SPINE OF
THE APPALACHIANS AND MOVE INTO OUR FAR EASTERN COUNTIES AROUND
MIDNIGHT. EXPECT TEMPERATURES TO WET BULB DOWN WHEN THE PCPN MOVES IN
AND TRANSITION THE RAIN TO SNOW IN THE HIGHER ELEVATIONS FIRST BUT
EVENTUALLY DOWN IN THE VALLEYS...AS WELL. THE HEAVIEST SNOW WILL FALL
IN THE HIGHER TERRAIN ALONG THE VIRGINIA BORDER WHERE AS MUCH AS A
QUARTER TO A THIRD OF AN INCH OF LIQUID WILL LIKELY OCCUR. THIS WILL
PROBABLY AMOUNT TO BETWEEN TWO AND THREE INCHES OF WET SNOW IN THE
HIGHER TERRAIN...ABOVE 2000 FEET AND AROUND AN INCH OR LESS
ELSEWHERE. HIGHER RIDGES BELOW 2000 FEET CAN EXPECT TO PICK UP
BETWEEN ONE AND TWO INCHES BY MIDDAY WEDNESDAY. HAVE SET UP THIS AREA
WITH A WINTER WEATHER ADVISORY FROM MIDNIGHT THROUGH NOON WEDNESDAY
FOR THIS PASSING EVENT. WITH THE POTENTIAL FOR LIGHT ACCUMULATIONS
IN THE COUNTIES IMMEDIATELY WEST OF THE ADVISORY WILL ALSO ISSUE AN
SPS ADDRESSING THIS MARGINAL CONCERN. OTHERWISE...THE COASTAL PULLS
OUT LATER WEDNESDAY WITH A BRIEF VISIT BY HIGH PRESSURE FOR EAST
KENTUCKY IN ITS WAKE. HOWEVER...THE NEXT DEVELOPING LOW WORKS IN FROM
THE NORTHWEST LATER THAT NIGHT CARVING ITS WAY THROUGH OUR SOUTHERN
COUNTIES INTO DAWN THURSDAY. THIS TOO WILL BRING SOME RAIN OR SNOW
TO PARTS OF THE AREA WITH SOME SLUSHY LIGHT SNOW ACCUMULATIONS
POSSIBLE MAINLY ON RIDGES AND GRASSY/ELEVATED SURFACES.
AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR T/TD/WINDS THROUGH
THE NEXT 24 HOURS AND THE SUPERBLEND THEREAFTER. DID MAKE SOME
MORE SIGNIFICANT TERRAIN BASED ADJUSTMENTS TONIGHT INTO WEDNESDAY IN
THE EXPECTED SNOW AREAS OF THE FAR EAST. AS FOR POPS...ENDED UP
CLOSE TO A BLEND OF THE MAV AND MET NUMBERS THROUGH THE PERIOD.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 354 PM EST TUE NOV 25 2014
SHORTWAVE ENERGY ROUNDING THE BASE OF THE TROUGH AND ASSOCIATED LOW
PRESSURE WILL BE MOVING EAST OF THE REGION WITH BEST POP CHANCES
ACROSS THE SE PORTIONS OF THE CWA. THIS WILL GENERALLY BE LIGHT
RAIN/SNOW SHOWERS AND DO NOT EXPECT MUCH QPF THROUGH THE DAY THURSDAY
AT THIS POINT. THIS SYSTEM SLIDES EAST ALLOWING FOR NW/W FLOW TO
SETUP ACROSS THE REGION AND THEREFORE HELD SLIGHT CHANCE IN FAR SE
INTO THE AFTERNOON.
SURFACE HIGH PRESSURE WILL SLOWLY SLIDE EAST THROUGH THE NIGHT
THURSDAY AND GENERALLY CRESTING ACROSS THE REGION EARLY FRIDAY. THIS
HIGH PRESSURE BUILDS EAST BRINGING RETURN SOUTHERLY FLOW TO EASTERN
KY WITH TEMPERATURES RISING INTO THE LOWER 50S SATURDAY. SATURDAY
AFTERNOON WE DO PRESENT SOME SLIGHT CHANCE SHOWERS ESPECIALLY ACROSS
THE FAR NORTH AS FRONTAL BOUNDARY GENERALLY STALLS ACROSS THE NORTH.
THIS QUASI-STATIONARY FRONT WILL KEEP THE WEATHER UNSETTLED THROUGH
THE PERIOD. THE QUESTION REALLY BECOMES HOW QUICKLY DOES THIS
BOUNDARY MOVE SOUTH...THAT SAID THE 12Z ECMWF IS MORE PROGRESSIVE
MOVING THIS FRONT SOUTH THAN THE 12Z GFS. RIGHT NOW WITH MODEL
DISCREPANCIES WILL KEEP BLEND POPS FOR THE MOST PART BUT WOULD THINK
THESE POPS WILL CONTINUE TO TREND UP ONCE MODELS COME INTO BETTER
ALIGNMENT. SATURDAY HIGHS ARE EXPECTED TO WARM INTO THE LOW TO MID
50S WITH TEMPERATURES MODIFYING INTO THE UPPER 50S TO LOWER 60S
THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 100 PM EST TUE NOV 25 2014
VFR CONDITIONS WILL CONTINUE THROUGH THIS EVENING AS HIGH PRESSURE
HOLD ON OVER THE AREA. A DEVELOPING LOW PRESSURE SYSTEM WILL SPREAD
MOISTURE AND LOWERING CLOUDS BACK INTO EASTERN KENTUCKY LATE
TONIGHT...WITH CIGS FALLING INTO THE MVFR RANGE IN THE EAST BY 08Z.
AS OF RIGHT NOW...LOOKS LIKE WE SHOULD SEE A GRADIENT IN THE LOWER
CIGS WITH THE LOWEST (IFR/MVFR) IN THE EAST...TRAILING BACK TO VFR IN
THE WEST...THROUGH MID MORNING WEDNESDAY. WE WILL ALSO SEE
PRECIPITATION SPREAD INTO THE AREA...MAINLY ACROSS SOUTHEASTERN
KENTUCKY...AS A MIX OF RAIN AND SNOW...LIKELY BECOMING ALL IN THE
PRE-DAWN HOURS. THIS SNOW WILL RESTRICT VISIBILITIES LATER TONIGHT
AS WELL...MAINLY AT KJKL AND KSJS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST
WEDNESDAY FOR KYZ087-088-110-113-115-117>120.
&&
$$
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
325 PM EST TUE NOV 25 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 325 PM EST TUE NOV 25 2014
...ACCUMULATING SNOW EXPECTED OVER FAR EASTERN KENTUCKY TONIGHT INTO
WEDNESDAY MORNING...
19Z SFC ANALYSIS SHOWS HIGH PRESSURE STILL INFLUENCING THE WEATHER OF
EASTERN KENTUCKY. THIS HAS PROVIDED PLENTY OF SUNSHINE AND GENERALLY
SOUTHWEST WINDS OF 5 TO 10 KTS WITH OCCASIONAL GUSTS TO 15 KTS. THESE
CONDITIONS...ALONG WITH GOOD DRYING THROUGH EARLY AFTERNOON HAS SENT
TEMPERATURES WELL UP INTO THE 50S FOR MOST OF THE AREA...THOUGH
LOCATIONS NORTHWEST OF INTERSTATE 64 ARE LAGGING IN THE UPPER 40S. OF
NOTE ON THE SFC CHART IS AN AREA OF DEVELOPING LOW PRESSURE CROSSING
NORTHERN FLORIDA ON ITS WAY TO THE SOUTHEAST U.S. SEABOARD.
THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT THROUGH THE FIRST PART
OF THE SHORT TERM FORECAST. THEY ALL TAKE A STRONG SHORTWAVE
CURRENTLY BOTTOMING OUT OVER THE CENTRAL GULF COAST NORTHEAST INTO
THE SOUTHERN APPALACHIANS BY WEDNESDAY MORNING. IN ADDITION...A
COMPACT WAVE WILL BE DROPPING SOUTHEAST FROM THE NORTHERN PLAINS INTO
THE MID MISSISSIPPI VALLEY AND EVENTUALLY THROUGH THE TENNESSEE
VALLEY LATER WEDNESDAY NIGHT. THE MODELS ARE CLOSE ON THE TIMING OF
THIS BUT THE CORE OF THE ENERGY IS FURTHER SOUTH IN THE NAM...
ECMWF...AND GEM WHEN COMPARED TO THE GFS. WILL FAVOR THIS MORE
SOUTHERN TRACK AS SEEN IN THE CONSENSUS. IN GENERAL HAVE LEANED MOST
CLOSELY TO THE HIGHER RESOLUTION MODELS OF THE NAM12 AND HRRR...
THOUGH THE HRRR PCPN FIELDS SEEM TOO FAR SOUTHEAST AND SLOW LATER
TONIGHT.
SENSIBLE WEATHER WILL FEATURE A QUICK INCREASE IN CLOUD COVER FROM
THE SOUTHEAST AS THE COASTAL LOW STARTS TO TAKE SHAPE LATER THIS
EVENING. LOWER CLOUDS AND PCPN WILL START TO SPILL OVER THE SPINE OF
THE APPALACHIANS AND MOVE INTO OUR FAR EASTERN COUNTIES AROUND
MIDNIGHT. EXPECT TEMPERATURES TO WET BULB DOWN WHEN THE PCPN MOVES IN
AND TRANSITION THE RAIN TO SNOW IN THE HIGHER ELEVATIONS FIRST BUT
EVENTUALLY DOWN IN THE VALLEYS...AS WELL. THE HEAVIEST SNOW WILL FALL
IN THE HIGHER TERRAIN ALONG THE VIRGINIA BORDER WHERE AS MUCH AS A
QUARTER TO A THIRD OF AN INCH OF LIQUID WILL LIKELY OCCUR. THIS WILL
PROBABLY AMOUNT TO BETWEEN TWO AND THREE INCHES OF WET SNOW IN THE
HIGHER TERRAIN...ABOVE 2000 FEET AND AROUND AN INCH OR LESS
ELSEWHERE. HIGHER RIDGES BELOW 2000 FEET CAN EXPECT TO PICK UP
BETWEEN ONE AND TWO INCHES BY MIDDAY WEDNESDAY. HAVE SET UP THIS AREA
WITH A WINTER WEATHER ADVISORY FROM MIDNIGHT THROUGH NOON WEDNESDAY
FOR THIS PASSING EVENT. WITH THE POTENTIAL FOR LIGHT ACCUMULATIONS
IN THE COUNTIES IMMEDIATELY WEST OF THE ADVISORY WILL ALSO ISSUE AN
SPS ADDRESSING THIS MARGINAL CONCERN. OTHERWISE...THE COASTAL PULLS
OUT LATER WEDNESDAY WITH A BRIEF VISIT BY HIGH PRESSURE FOR EAST
KENTUCKY IN ITS WAKE. HOWEVER...THE NEXT DEVELOPING LOW WORKS IN FROM
THE NORTHWEST LATER THAT NIGHT CARVING ITS WAY THROUGH OUR SOUTHERN
COUNTIES INTO DAWN THURSDAY. THIS TOO WILL BRING SOME RAIN OR SNOW
TO PARTS OF THE AREA WITH SOME SLUSHY LIGHT SNOW ACCUMULATIONS
POSSIBLE MAINLY ON RIDGES AND GRASSY/ELEVATED SURFACES.
AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR T/TD/WINDS THROUGH
THE NEXT 24 HOURS AND THE SUPERBLEND THEREAFTER. DID MAKE SOME
MORE SIGNIFICANT TERRAIN BASED ADJUSTMENTS TONIGHT INTO WEDNESDAY IN
THE EXPECTED SNOW AREAS OF THE FAR EAST. AS FOR POPS...ENDED UP
CLOSE TO A BLEND OF THE MAV AND MET NUMBERS THROUGH THE PERIOD.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 307 AM EST TUE NOV 25 2014
THE MODELS BEGIN THE PERIOD IN PRETTY GOOD AGREEMENT...WITH A LARGE
SCALE UPPER LEVEL TROUGH OF LOW PRESSURE EJECTING OUT OF THE
NORTHERN PLAINS AND ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS
WEDNESDAY NIGHT THROUGH FRIDAY. IT APPEARS THAT THIS INITIAL SYSTEM
WILL BE FAIRLY PROGRESSIVE...SO ANY PRECIPITATION ASSOCIATED WITH IT
SHOULD BE SHORT LIVED AND NOT VERY HEAVY. A SHOT OF COLD AIR WILL
SPILL INTO THE REGION AS THE SYSTEM DEPARTS...WITH HIGHS ON THURSDAY
ONLY TOPPING OUT AROUND 40 DEGREES...AFTER MORNING LOWS IN THE UPPER
20S AND LOWER 30S. A RIDGE OF HIGH PRESSURE IS THEN PROGGED TO
BECOME ESTABLISHED ACROSS THE REGION TO BEGIN THE WEEKEND...WITH
WARMER TEMPERATURES AND PARTLY CLOUDY SKIES ON TAP FOR FRIDAY NIGHT
AND SATURDAY. SATURDAY COULD MARK THE START OF A SIGNIFICANT WARMING
TREND...WITH HIGHS POSSIBLY TOPPING OUT IN THE LOW TO MID 50S. THE
REGION IS EXPECTED TO WARM EVEN MORE ON SUNDAY AND MONDAY...AS THE
MERCURY CLIMBS INTO THE MID TO UPPER 50S FOR MOST LOCATIONS BOTH
DAYS. OVERNIGHT LOWS SATURDAY AND SUNDAY NIGHT WILL FEEL ALMOST
BALMY IF THEY IN FACT ONLY DROP INTO THE LOW TO MID 40S EACH NIGHT.
ENOUGH COLD AIR WILL LIKELY SPILL INTO THE REGION TO BEGIN THE
PERIOD TO ALLOW FOR SOME SNOW TO MIX WITH RAIN EARLY WEDNESDAY NIGHT
INTO THURSDAY MORNING ACROSS THE AREA. LITTLE IF ANY SNOW
ACCUMULATION IS EXPECTED. THE NEXT ROUND OF PRECIPITATION IS
EXPECTED TO MOVE ACROSS THE AREA BEGINNING SATURDAY NIGHT...AS A
WEAK FRONTAL BOUNDARY MOVES INTO AND STALLS OUT ACROSS THE AREA. THE
MODELS KEEP THE FRONT IN PLACE...AND THEREFORE THE THREAT OF
PRECIPITATION...THROUGH THE END OF THE DAY ON MONDAY. TEMPERATURES
DURING THIS PERIOD WILL REMAIN WARM ENOUGH FOR ANY PRECIPITATION
THAT OCCURS TO REMAIN IN LIQUID FORM. DUE TO SOME SMALL TIMING
DIFFERENCES BETWEEN THE MODELS REGARDING PRECIPITATION
ONSET...DURATION...AND AREAL COVERAGE...DECIDED TO GO WITH ONLY
CHANCE POPS AT THIS TIME. BASED ON THE LATEST MODEL DATA...THE FRONT
COULD EITHER REMAIN STALLED ACROSS THE AREA...ECMWF...OR DRIFT
SLOWLY NORTH AS A WEAK WARM FRONT...GFS...DURING THE MONDAY INTO
MONDAY NIGHT TIME FRAME. ONLY TIME WILL TELL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 100 PM EST TUE NOV 25 2014
VFR CONDITIONS WILL CONTINUE THROUGH THIS EVENING AS HIGH PRESSURE
HOLD ON OVER THE AREA. A DEVELOPING LOW PRESSURE SYSTEM WILL SPREAD
MOISTURE AND LOWERING CLOUDS BACK INTO EASTERN KENTUCKY LATE
TONIGHT...WITH CIGS FALLING INTO THE MVFR RANGE IN THE EAST BY 08Z.
AS OF RIGHT NOW...LOOKS LIKE WE SHOULD SEE A GRADIENT IN THE LOWER
CIGS WITH THE LOWEST (IFR/MVFR) IN THE EAST...TRAILING BACK TO VFR IN
THE WEST...THROUGH MID MORNING WEDNESDAY. WE WILL ALSO SEE
PRECIPITATION SPREAD INTO THE AREA...MAINLY ACROSS SOUTHEASTERN
KENTUCKY...AS A MIX OF RAIN AND SNOW...LIKELY BECOMING ALL IN THE
PRE-DAWN HOURS. THIS SNOW WILL RESTRICT VISIBILITIES LATER TONIGHT
AS WELL...MAINLY AT KJKL AND KSJS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST
WEDNESDAY FOR KYZ087-088-110-113-115-117>120.
&&
$$
SHORT TERM...GREIF
LONG TERM...AR
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
120 PM EST TUE NOV 25 2014
.UPDATE...
ISSUED AT 120 PM EST TUE NOV 25 2014
DID A QUICK PRIMARILY TO BUMP UP TEMPERATURES GIVEN THE SUNNY SKIES
AND DRIER AIR IN PLACE. ALSO TWEAKED THE HOURLY TEMPS AND DEWPOINTS
PER THE LATEST OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND
WEB SERVERS.
UPDATE ISSUED AT 1025 AM EST TUE NOV 25 2014
14Z SFC ANALYSIS SHOWS HIGH PRESSURE BRIEFLY BUILDING INTO EAST
KENTUCKY THIS MORNING BRINGING SUNNY SKIES AND A DRIER AIR MASS. THE
EARLIER HIGH CLOUDS HAVE SLID OFF TO THE EAST OF THE STATE AND WINDS
ARE LIGHT AND VARIABLE. TEMPERATURES ARE IN THE LOW TO MID 40S IN
MOST PLACES ACROSS THE CWA NOW THAT THE COLDER VALLEYS ARE STARTING
TO MIX OUT. DEWPOINTS ARE CURRENTLY IN THE LOW 30S...BUT WITH DRIER
AIR OFF THE SFC THESE ARE EXPECTED TO MIX DOWN INTO THE 20S THROUGH
MID AFTERNOON. FIRST GLANCE OF THE LATEST NAM12 SHOWS THE SOUTHEAST
LOW A BIT FURTHER EAST FROM THE MORE AGGRESSIVE 06Z RUN. HOWEVER...IT
STILL HAS A SIGNIFICANT AMOUNT OF PCPN FALLING TONIGHT INTO WEDNESDAY
MORNING IN AND NEAR THE VIRGINIA BORDER COUNTIES WHERE MUCH OF IT
WILL LIKELY WET BULB TO SNOW. SOME ACCUMULATIONS APPEAR LIKELY...
PARTICULARLY IN THE HIGHER ELEVATIONS AND ON GRASSY/ELEVATED SFCS
ELSEWHERE. THE SPS CONTINUES BUT MAY NEED TO BE UPGRADED TO AN
ADVISORY LATER THIS AFTERNOON DEPENDING ON HOW THE OTHER MODELS COME
IN. FOR THIS UPDATE...HAVE MAINLY FINE TUNED T AND TD GRIDS INTO THE
AFTERNOON PER THE LATEST OBS...TRENDS...AND CONSSHORT GUIDANCE. THESE
HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 621 AM EST TUE NOV 25 2014
06Z NAM AND GFS ARE NOW IN AND BOTH ARE A LITTLE MORE ROBUST WITH
PRECIPITATION AND BOTH A TAD FARTHER WEST WITH THE EXTENT. IN
FACT...THE NAM SNOWFALL ALGORITHM IS SUGGESTING AS MUCH AS 5 INCHES
OF SNOW COULD FALL OVER FAR SOUTHEAST KENTUCKY. HOWEVER...THIS IS THE
FIRST RUN SUGGESTING THIS HIGH OF QPF AND WILLING TO CONSIDER IT AN
OUTLIER FOR NOW...BUT THE 12Z MODEL GUIDANCE WILL HAVE TO BE WATCHED
FOR POSSIBLE TRENDS TOWARDS THE HIGHER SNOWFALL AMOUNTS TONIGHT.
ALREADY SEEING SOME COOLER CLOUD TOPS DEVELOPING ACROSS EAST
TEXAS...SO AS MENTIONED...MAY NEED TO WATCH FOR A FARTHER WEST EXTENT
TO THE PRECIPITATION.
ALSO SOMETHING ELSE TO CONSIDER...DRY AIR MIX DOWN ACROSS SOUTHEAST
KENTUCKY THIS AFTERNOON MAY BRING DOWN SOME AWFULLY LOW
DEWPOINTS...WHICH WOULD SET THE STAGE FOR GOOD WET BULB COOLING AS
PRECIPITATION MOVES IN TONIGHT. THUS...IF LOWER DEWPOINTS
MATERIALIZE...THEY MAY HELP DISTINGUISH BETWEEN WHO GETS MORE
SNOW...VERSES MORE RAIN. LOWER DEWPOINTS WOULD ALLOW FOR A FASTER
TRANSITION TO SNOW...AND THUS...MORE SNOWFALL ACCUMULATION. FOR
NOW...WILLING TO SIT ON THIS AND LET DAY-SHIFT RE-EVALUATE THE NEED
FOR ANY CHANGES. IF MODELS CONTINUE TO HOLD COURSE...IT LOOKS LIKE AT
A MINIMUM A WINTER WEATHER ADVISORY WOULD BE NEEDED FOR A PORTION OF
THE AREA.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 307 AM EST TUE NOV 25 2014
SURFACE RIDGING CONTINUES TO BUILD INTO EASTERN KENTUCKY THIS MORNING
WITH SKIES GENERALLY CLEAR TO MOSTLY CLEAR. THIS WILL HOLD THROUGH
THE DAY...PROVIDING A COOLER...BUT STILL RELATIVELY PLEASANT DAY. IN
FACT...WITH THE HELP OF THE SUNSHINE AND TEMPERATURES IN SOME PLACES
ALREADY IN THE 40S THIS MORNING...WE SHOULD HAVE NO PROBLEM
SURPASSING THE 50 DEGREE MARK THIS AFTERNOON. WITH AN ABUNDANCE OF LOW
LEVEL DRY AIR JUST OFF THE SURFACE...RAP AND HRRR ARE SUGGESTING
FAIRLY LOW DEWPOINTS THIS AFTERNOON...ESPECIALLY ACROSS SOUTHEAST
KENTUCKY. IT MIGHT BE A STRETCH TO FALL INTO THE TEENS...BUT
CERTAINLY DEWPOINTS DOWN INTO THE MID 20S WILL BE POSSIBLE. THIS WILL
PUT US CLOSE TO THE 25 PERCENT RH`S THIS AFTERNOON. I WOULDN`T BE
SURPRISED TO SEE A FEW SPOTS ACTUALLY REACH THIS VALUE...ESPECIALLY
IN SOUTHEAST KENTUCKY.
CLOUDS WILL BE ON THE INCREASE THIS EVENING AND ESPECIALLY TONIGHT.
MODELS HAVE AN AREA OF LOW PRESSURE DEVELOPING OVER FLORIDA AND
TRACKING NORTHWARD ALONG THE COAST TONIGHT. NEARLY ALL MODELS ARE IN
SUPPORT OF MOISTURE AND LIFT ASSOCIATED WITH THIS SYSTEM DEVELOPING
ACROSS FAR SOUTHEAST AND EAST KENTUCKY OVERNIGHT INTO WEDNESDAY
MORNING. GIVEN THE ABUNDANCE OF DRY AIR IN PLACE...WET BULB
TEMPERATURES WILL BE FAIRLY LOW. ASSUMING WE GET PRECIP RATES THAT
SUPPORT IT...WE SHOULD SEE PRIMARILY SNOW LATE TONIGHT INTO WEDNESDAY
MORNING...BUT SOME RAIN MAY BE POSSIBLE FARTHER INTO EASTERN KENTUCKY
WHERE PRECIP RATES MAY NOT BE AS HIGH. REGARDLESS...WE SHOULD SEE
TEMPERATURES COOL ENOUGH TO SUPPORT SOME LIGHT SNOW ACCUMULATION
ACROSS SOUTHEAST KENTUCKY. AT THIS TIME...THE HIGHEST AMOUNTS SHOULD
BE ABOVE 2500 FEET...WHERE 2 TO 3 INCHES OF SNOW MAY BE POSSIBLE.
LIGHTER AMOUNTS IN THE LOWER ELEVATIONS UP TO AN INCH WILL BE
POSSIBLE FOR AREAS SOUTHEAST OF A LINE FROM INEZ TO HAZARD...TO
BARBOURVILLE. WHILE SNOW IS EXPECTED ACROSS SOUTHEAST KENTUCKY...THE
REST OF EASTERN KENTUCKY MAY NOT SEE MUCH MORE THAN INCREASED CLOUD
COVER. PLAN TO GO AHEAD AND ISSUE AN SPS FOR OUR SOUTHEAST COUNTIES
TO ADDRESS THE POTENTIAL SNOWFALL. GIVEN THE EXPECTED CLOUD COVER
INTO WEDNESDAY...WENT WITH A PRETTY GOOD GRADIENT IN TEMPERATURES
FROM WEST TO EAST...WITH READINGS AROUND 50 IN THE WEST TO LOW AND
MID 30S IN THE EAST. PRECIPITATION WILL DEPART BY MIDDAY
WEDNESDAY...WITH TEMPORARY BREAK IN PRECIPITATION EXPECTED THROUGH
THE AFTERNOON AND EVENING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 307 AM EST TUE NOV 25 2014
THE MODELS BEGIN THE PERIOD IN PRETTY GOOD AGREEMENT...WITH A LARGE
SCALE UPPER LEVEL TROUGH OF LOW PRESSURE EJECTING OUT OF THE
NORTHERN PLAINS AND ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS
WEDNESDAY NIGHT THROUGH FRIDAY. IT APPEARS THAT THIS INITIAL SYSTEM
WILL BE FAIRLY PROGRESSIVE...SO ANY PRECIPITATION ASSOCIATED WITH IT
SHOULD BE SHORT LIVED AND NOT VERY HEAVY. A SHOT OF COLD AIR WILL
SPILL INTO THE REGION AS THE SYSTEM DEPARTS...WITH HIGHS ON THURSDAY
ONLY TOPPING OUT AROUND 40 DEGREES...AFTER MORNING LOWS IN THE UPPER
20S AND LOWER 30S. A RIDGE OF HIGH PRESSURE IS THEN PROGGED TO
BECOME ESTABLISHED ACROSS THE REGION TO BEGIN THE WEEKEND...WITH
WARMER TEMPERATURES AND PARTLY CLOUDY SKIES ON TAP FOR FRIDAY NIGHT
AND SATURDAY. SATURDAY COULD MARK THE START OF A SIGNIFICANT WARMING
TREND...WITH HIGHS POSSIBLY TOPPING OUT IN THE LOW TO MID 50S. THE
REGION IS EXPECTED TO WARM EVEN MORE ON SUNDAY AND MONDAY...AS THE
MERCURY CLIMBS INTO THE MID TO UPPER 50S FOR MOST LOCATIONS BOTH
DAYS. OVERNIGHT LOWS SATURDAY AND SUNDAY NIGHT WILL FEEL ALMOST
BALMY IF THEY IN FACT ONLY DROP INTO THE LOW TO MID 40S EACH NIGHT.
ENOUGH COLD AIR WILL LIKELY SPILL INTO THE REGION TO BEGIN THE
PERIOD TO ALLOW FOR SOME SNOW TO MIX WITH RAIN EARLY WEDNESDAY NIGHT
INTO THURSDAY MORNING ACROSS THE AREA. LITTLE IF ANY SNOW
ACCUMULATION IS EXPECTED. THE NEXT ROUND OF PRECIPITATION IS
EXPECTED TO MOVE ACROSS THE AREA BEGINNING SATURDAY NIGHT...AS A
WEAK FRONTAL BOUNDARY MOVES INTO AND STALLS OUT ACROSS THE AREA. THE
MODELS KEEP THE FRONT IN PLACE...AND THEREFORE THE THREAT OF
PRECIPITATION...THROUGH THE END OF THE DAY ON MONDAY. TEMPERATURES
DURING THIS PERIOD WILL REMAIN WARM ENOUGH FOR ANY PRECIPITATION
THAT OCCURS TO REMAIN IN LIQUID FORM. DUE TO SOME SMALL TIMING
DIFFERENCES BETWEEN THE MODELS REGARDING PRECIPITATION
ONSET...DURATION...AND AREAL COVERAGE...DECIDED TO GO WITH ONLY
CHANCE POPS AT THIS TIME. BASED ON THE LATEST MODEL DATA...THE FRONT
COULD EITHER REMAIN STALLED ACROSS THE AREA...ECMWF...OR DRIFT
SLOWLY NORTH AS A WEAK WARM FRONT...GFS...DURING THE MONDAY INTO
MONDAY NIGHT TIME FRAME. ONLY TIME WILL TELL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 100 PM EST TUE NOV 25 2014
VFR CONDITIONS WILL CONTINUE THROUGH THIS EVENING AS HIGH PRESSURE
HOLD ON OVER THE AREA. A DEVELOPING LOW PRESSURE SYSTEM WILL SPREAD
MOISTURE AND LOWERING CLOUDS BACK INTO EASTERN KENTUCKY LATE
TONIGHT...WITH CIGS FALLING INTO THE MVFR RANGE IN THE EAST BY 08Z.
AS OF RIGHT NOW...LOOKS LIKE WE SHOULD SEE A GRADIENT IN THE LOWER
CIGS WITH THE LOWEST (IFR/MVFR) IN THE EAST...TRAILING BACK TO VFR IN
THE WEST...THROUGH MID MORNING WEDNESDAY. WE WILL ALSO SEE
PRECIPITATION SPREAD INTO THE AREA...MAINLY ACROSS SOUTHEASTERN
KENTUCKY...AS A MIX OF RAIN AND SNOW...LIKELY BECOMING ALL IN THE
PRE-DAWN HOURS. THIS SNOW WILL RESTRICT VISIBILITIES LATER TONIGHT
AS WELL...MAINLY AT KJKL AND KSJS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...KAS
LONG TERM...AR
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1025 AM EST TUE NOV 25 2014
.UPDATE...
ISSUED AT 1025 AM EST TUE NOV 25 2014
14Z SFC ANALYSIS SHOWS HIGH PRESSURE BRIEFLY BUILDING INTO EAST
KENTUCKY THIS MORNING BRINGING SUNNY SKIES AND A DRIER AIR MASS. THE
EARLIER HIGH CLOUDS HAVE SLID OFF TO THE EAST OF THE STATE AND WINDS
ARE LIGHT AND VARIABLE. TEMPERATURES ARE IN THE LOW TO MID 40S IN
MOST PLACES ACROSS THE CWA NOW THAT THE COLDER VALLEYS ARE STARTING
TO MIX OUT. DEWPOINTS ARE CURRENTLY IN THE LOW 30S...BUT WITH DRIER
AIR OFF THE SFC THESE ARE EXPECTED TO MIX DOWN INTO THE 20S THROUGH
MID AFTERNOON. FIRST GLANCE OF THE LATEST NAM12 SHOWS THE SOUTHEAST
LOW A BIT FURTHER EAST FROM THE MORE AGGRESSIVE 06Z RUN. HOWEVER...IT
STILL HAS A SIGNIFICANT AMOUNT OF PCPN FALLING TONIGHT INTO WEDNESDAY
MORNING IN AND NEAR THE VIRGINIA BORDER COUNTIES WHERE MUCH OF IT
WILL LIKELY WET BULB TO SNOW. SOME ACCUMULATIONS APPEAR LIKELY...
PARTICULARLY IN THE HIGHER ELEVATIONS AND ON GRASSY/ELEVATED SFCS
ELSEWHERE. THE SPS CONTINUES BUT MAY NEED TO BE UPGRADED TO AN
ADVISORY LATER THIS AFTERNOON DEPENDING ON HOW THE OTHER MODELS COME
IN. FOR THIS UPDATE...HAVE MAINLY FINE TUNED T AND TD GRIDS INTO THE
AFTERNOON PER THE LATEST OBS...TRENDS...AND CONSSHORT GUIDANCE. THESE
HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 621 AM EST TUE NOV 25 2014
06Z NAM AND GFS ARE NOW IN AND BOTH ARE A LITTLE MORE ROBUST WITH
PRECIPITATION AND BOTH A TAD FARTHER WEST WITH THE EXTENT. IN
FACT...THE NAM SNOWFALL ALGORITHM IS SUGGESTING AS MUCH AS 5 INCHES
OF SNOW COULD FALL OVER FAR SOUTHEAST KENTUCKY. HOWEVER...THIS IS THE
FIRST RUN SUGGESTING THIS HIGH OF QPF AND WILLING TO CONSIDER IT AN
OUTLIER FOR NOW...BUT THE 12Z MODEL GUIDANCE WILL HAVE TO BE WATCHED
FOR POSSIBLE TRENDS TOWARDS THE HIGHER SNOWFALL AMOUNTS TONIGHT.
ALREADY SEEING SOME COOLER CLOUD TOPS DEVELOPING ACROSS EAST
TEXAS...SO AS MENTIONED...MAY NEED TO WATCH FOR A FARTHER WEST EXTENT
TO THE PRECIPITATION.
ALSO SOMETHING ELSE TO CONSIDER...DRY AIR MIX DOWN ACROSS SOUTHEAST
KENTUCKY THIS AFTERNOON MAY BRING DOWN SOME AWFULLY LOW
DEWPOINTS...WHICH WOULD SET THE STAGE FOR GOOD WET BULB COOLING AS
PRECIPITATION MOVES IN TONIGHT. THUS...IF LOWER DEWPOINTS
MATERIALIZE...THEY MAY HELP DISTINGUISH BETWEEN WHO GETS MORE
SNOW...VERSES MORE RAIN. LOWER DEWPOINTS WOULD ALLOW FOR A FASTER
TRANSITION TO SNOW...AND THUS...MORE SNOWFALL ACCUMULATION. FOR
NOW...WILLING TO SIT ON THIS AND LET DAY-SHIFT RE-EVALUATE THE NEED
FOR ANY CHANGES. IF MODELS CONTINUE TO HOLD COURSE...IT LOOKS LIKE AT
A MINIMUM A WINTER WEATHER ADVISORY WOULD BE NEEDED FOR A PORTION OF
THE AREA.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 307 AM EST TUE NOV 25 2014
SURFACE RIDGING CONTINUES TO BUILD INTO EASTERN KENTUCKY THIS MORNING
WITH SKIES GENERALLY CLEAR TO MOSTLY CLEAR. THIS WILL HOLD THROUGH
THE DAY...PROVIDING A COOLER...BUT STILL RELATIVELY PLEASANT DAY. IN
FACT...WITH THE HELP OF THE SUNSHINE AND TEMPERATURES IN SOME PLACES
ALREADY IN THE 40S THIS MORNING...WE SHOULD HAVE NO PROBLEM
SURPASSING THE 50 DEGREE MARK THIS AFTERNOON. WITH AN ABUNDANCE OF LOW
LEVEL DRY AIR JUST OFF THE SURFACE...RAP AND HRRR ARE SUGGESTING
FAIRLY LOW DEWPOINTS THIS AFTERNOON...ESPECIALLY ACROSS SOUTHEAST
KENTUCKY. IT MIGHT BE A STRETCH TO FALL INTO THE TEENS...BUT
CERTAINLY DEWPOINTS DOWN INTO THE MID 20S WILL BE POSSIBLE. THIS WILL
PUT US CLOSE TO THE 25 PERCENT RH`S THIS AFTERNOON. I WOULDN`T BE
SURPRISED TO SEE A FEW SPOTS ACTUALLY REACH THIS VALUE...ESPECIALLY
IN SOUTHEAST KENTUCKY.
CLOUDS WILL BE ON THE INCREASE THIS EVENING AND ESPECIALLY TONIGHT.
MODELS HAVE AN AREA OF LOW PRESSURE DEVELOPING OVER FLORIDA AND
TRACKING NORTHWARD ALONG THE COAST TONIGHT. NEARLY ALL MODELS ARE IN
SUPPORT OF MOISTURE AND LIFT ASSOCIATED WITH THIS SYSTEM DEVELOPING
ACROSS FAR SOUTHEAST AND EAST KENTUCKY OVERNIGHT INTO WEDNESDAY
MORNING. GIVEN THE ABUNDANCE OF DRY AIR IN PLACE...WET BULB
TEMPERATURES WILL BE FAIRLY LOW. ASSUMING WE GET PRECIP RATES THAT
SUPPORT IT...WE SHOULD SEE PRIMARILY SNOW LATE TONIGHT INTO WEDNESDAY
MORNING...BUT SOME RAIN MAY BE POSSIBLE FARTHER INTO EASTERN KENTUCKY
WHERE PRECIP RATES MAY NOT BE AS HIGH. REGARDLESS...WE SHOULD SEE
TEMPERATURES COOL ENOUGH TO SUPPORT SOME LIGHT SNOW ACCUMULATION
ACROSS SOUTHEAST KENTUCKY. AT THIS TIME...THE HIGHEST AMOUNTS SHOULD
BE ABOVE 2500 FEET...WHERE 2 TO 3 INCHES OF SNOW MAY BE POSSIBLE.
LIGHTER AMOUNTS IN THE LOWER ELEVATIONS UP TO AN INCH WILL BE
POSSIBLE FOR AREAS SOUTHEAST OF A LINE FROM INEZ TO HAZARD...TO
BARBOURVILLE. WHILE SNOW IS EXPECTED ACROSS SOUTHEAST KENTUCKY...THE
REST OF EASTERN KENTUCKY MAY NOT SEE MUCH MORE THAN INCREASED CLOUD
COVER. PLAN TO GO AHEAD AND ISSUE AN SPS FOR OUR SOUTHEAST COUNTIES
TO ADDRESS THE POTENTIAL SNOWFALL. GIVEN THE EXPECTED CLOUD COVER
INTO WEDNESDAY...WENT WITH A PRETTY GOOD GRADIENT IN TEMPERATURES
FROM WEST TO EAST...WITH READINGS AROUND 50 IN THE WEST TO LOW AND
MID 30S IN THE EAST. PRECIPITATION WILL DEPART BY MIDDAY
WEDNESDAY...WITH TEMPORARY BREAK IN PRECIPITATION EXPECTED THROUGH
THE AFTERNOON AND EVENING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 307 AM EST TUE NOV 25 2014
THE MODELS BEGIN THE PERIOD IN PRETTY GOOD AGREEMENT...WITH A LARGE
SCALE UPPER LEVEL TROUGH OF LOW PRESSURE EJECTING OUT OF THE
NORTHERN PLAINS AND ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS
WEDNESDAY NIGHT THROUGH FRIDAY. IT APPEARS THAT THIS INITIAL SYSTEM
WILL BE FAIRLY PROGRESSIVE...SO ANY PRECIPITATION ASSOCIATED WITH IT
SHOULD BE SHORT LIVED AND NOT VERY HEAVY. A SHOT OF COLD AIR WILL
SPILL INTO THE REGION AS THE SYSTEM DEPARTS...WITH HIGHS ON THURSDAY
ONLY TOPPING OUT AROUND 40 DEGREES...AFTER MORNING LOWS IN THE UPPER
20S AND LOWER 30S. A RIDGE OF HIGH PRESSURE IS THEN PROGGED TO
BECOME ESTABLISHED ACROSS THE REGION TO BEGIN THE WEEKEND...WITH
WARMER TEMPERATURES AND PARTLY CLOUDY SKIES ON TAP FOR FRIDAY NIGHT
AND SATURDAY. SATURDAY COULD MARK THE START OF A SIGNIFICANT WARMING
TREND...WITH HIGHS POSSIBLY TOPPING OUT IN THE LOW TO MID 50S. THE
REGION IS EXPECTED TO WARM EVEN MORE ON SUNDAY AND MONDAY...AS THE
MERCURY CLIMBS INTO THE MID TO UPPER 50S FOR MOST LOCATIONS BOTH
DAYS. OVERNIGHT LOWS SATURDAY AND SUNDAY NIGHT WILL FEEL ALMOST
BALMY IF THEY IN FACT ONLY DROP INTO THE LOW TO MID 40S EACH NIGHT.
ENOUGH COLD AIR WILL LIKELY SPILL INTO THE REGION TO BEGIN THE
PERIOD TO ALLOW FOR SOME SNOW TO MIX WITH RAIN EARLY WEDNESDAY NIGHT
INTO THURSDAY MORNING ACROSS THE AREA. LITTLE IF ANY SNOW
ACCUMULATION IS EXPECTED. THE NEXT ROUND OF PRECIPITATION IS
EXPECTED TO MOVE ACROSS THE AREA BEGINNING SATURDAY NIGHT...AS A
WEAK FRONTAL BOUNDARY MOVES INTO AND STALLS OUT ACROSS THE AREA. THE
MODELS KEEP THE FRONT IN PLACE...AND THEREFORE THE THREAT OF
PRECIPITATION...THROUGH THE END OF THE DAY ON MONDAY. TEMPERATURES
DURING THIS PERIOD WILL REMAIN WARM ENOUGH FOR ANY PRECIPITATION
THAT OCCURS TO REMAIN IN LIQUID FORM. DUE TO SOME SMALL TIMING
DIFFERENCES BETWEEN THE MODELS REGARDING PRECIPITATION
ONSET...DURATION...AND AREAL COVERAGE...DECIDED TO GO WITH ONLY
CHANCE POPS AT THIS TIME. BASED ON THE LATEST MODEL DATA...THE FRONT
COULD EITHER REMAIN STALLED ACROSS THE AREA...ECMWF...OR DRIFT
SLOWLY NORTH AS A WEAK WARM FRONT...GFS...DURING THE MONDAY INTO
MONDAY NIGHT TIME FRAME. ONLY TIME WILL TELL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 621 AM EST TUE NOV 25 2014
VFR CONDITIONS WILL CONTINUE THROUGH THIS EVENING AS HIGH PRESSURE
PUSHES EAST ACROSS THE AREA. A DEVELOPING LOW PRESSURE SYSTEM WILL
SPREAD MOISTURE BACK INTO EASTERN KENTUCKY LATE TONIGHT...WITH CIGS
LOWERING. AS OF RIGHT NOW...LOOKS LIKE WE SHOULD SEE A GRADIENT IN
THE LOWER CIGS WITH THE LOWEST (IFR/MVFR) IN THE EAST...TRAILING
BACK TO VFR IN THE WEST. WE WILL ALSO SEE PRECIPITATION SPREAD INTO
THE AREA...MAINLY ACROSS SOUTHEASTERN KENTUCKY...WITH A MIX OF RAIN
AND SNOW...LIKELY BECOMING ALL SNOW. THIS WILL RESTRICT VISIBILITIES
BY LATE TONIGHT AS WELL...MAINLY AT KJKL AND KSJS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...KAS
LONG TERM...AR
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
621 AM EST TUE NOV 25 2014
.UPDATE...
ISSUED AT 621 AM EST TUE NOV 25 2014
O6Z NAM AND GFS ARE NOW IN AND BOTH ARE A LITTLE MORE ROBUST WITH
PRECIPITATION AND BOTH A TAD FARTHER WEST WITH THE EXTENT. IN
FACT...THE NAM SNOWFALL ALGORITHM IS SUGGESTING AS MUCH AS 5 INCHES
OF SNOW COULD FALL OVER FAR SOUTHEAST KENTUCKY. HOWEVER...THIS IS THE
FIRST RUN SUGGESTING THIS HIGH OF QPF AND WILLING TO CONSIDER IT AN
OUTLIER FOR NOW...BUT THE 12Z MODEL GUIDANCE WILL HAVE TO BE WATCHED
FOR POSSIBLE TRENDS TOWARDS THE HIGHER SNOWFALL AMOUNTS TONIGHT.
ALREADY SEEING SOME COOLER CLOUD TOPS DEVELOPING ACROSS EAST
TEXAS...SO AS MENTIONED...MAY NEED TO WATCH FOR A FARTHER WEST EXTENT
TO THE PRECIPITATION.
ALSO SOMETHING ELSE TO CONSIDER...DRY AIR MIX DOWN ACROSS SOUTHEAST
KENTUCKY THIS AFTERNOON MAY BRING DOWN SOME AWFULLY LOW
DEWPOINTS...WHICH WOULD SET THE STAGE FOR GOOD WET BULB COOLING AS
PRECIPITATION MOVES IN TONIGHT. THUS...IF LOWER DEWPOINTS
MATERIALIZE...THEY MAY HELP DISTINGUISH BETWEEN WHO GETS MORE
SNOW...VERSES MORE RAIN. LOWER DEWPOINTS WOULD ALLOW FOR A FASTER
TRANSITION TO SNOW...AND THUS...MORE SNOWFALL ACCUMULATION. FOR
NOW...WILLING TO SIT ON THIS AND LET DAY-SHIFT RE-EVALUATE THE NEED
FOR ANY CHANGES. IF MODELS CONTINUE TO HOLD COURSE...IT LOOKS LIKE AT
A MINIMUM A WINTER WEATHER ADVISORY WOULD BE NEEDED FOR A PORTION OF
THE AREA.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 307 AM EST TUE NOV 25 2014
SURFACE RIDGING CONTINUES TO BUILD INTO EASTERN KENTUCKY THIS MORNING
WITH SKIES GENERALLY CLEAR TO MOSTLY CLEAR. THIS WILL HOLD THROUGH
THE DAY...PROVIDING A COOLER...BUT STILL RELATIVELY PLEASANT DAY. IN
FACT...WITH THE HELP OF THE SUNSHINE AND TEMPERATURES IN SOME PLACES
ALREADY IN THE 40S THIS MORNING...WE SHOULD HAVE NO PROBLEM
SURPASSING THE 50 DEGREE MARK THIS AFTERNOON. WITH AN ABUNDANCE OF LOW
LEVEL DRY AIR JUST OFF THE SURFACE...RAP AND HRRR ARE SUGGESTING
FAIRLY LOW DEWPOINTS THIS AFTERNOON...ESPECIALLY ACROSS SOUTHEAST
KENTUCKY. IT MIGHT BE A STRETCH TO FALL INTO THE TEENS...BUT
CERTAINLY DEWPOINTS DOWN INTO THE MID 20S WILL BE POSSIBLE. THIS WILL
PUT US CLOSE TO THE 25 PERCENT RH`S THIS AFTERNOON. I WOULDN`T BE
SURPRISED TO SEE A FEW SPOTS ACTUALLY REACH THIS VALUE...ESPECIALLY
IN SOUTHEAST KENTUCKY.
CLOUDS WILL BE ON THE INCREASE THIS EVENING AND ESPECIALLY TONIGHT.
MODELS HAVE AN AREA OF LOW PRESSURE DEVELOPING OVER FLORIDA AND
TRACKING NORTHWARD ALONG THE COAST TONIGHT. NEARLY ALL MODELS ARE IN
SUPPORT OF MOISTURE AND LIFT ASSOCIATED WITH THIS SYSTEM DEVELOPING
ACROSS FAR SOUTHEAST AND EAST KENTUCKY OVERNIGHT INTO WEDNESDAY
MORNING. GIVEN THE ABUNDANCE OF DRY AIR IN PLACE...WET BULB
TEMPERATURES WILL BE FAIRLY LOW. ASSUMING WE GET PRECIP RATES THAT
SUPPORT IT...WE SHOULD SEE PRIMARILY SNOW LATE TONIGHT INTO WEDNESDAY
MORNING...BUT SOME RAIN MAY BE POSSIBLE FARTHER INTO EASTERN KENTUCKY
WHERE PRECIP RATES MAY NOT BE AS HIGH. REGARDLESS...WE SHOULD SEE
TEMPERATURES COOL ENOUGH TO SUPPORT SOME LIGHT SNOW ACCUMULATION
ACROSS SOUTHEAST KENTUCKY. AT THIS TIME...THE HIGHEST AMOUNTS SHOULD
BE ABOVE 2500 FEET...WHERE 2 TO 3 INCHES OF SNOW MAY BE POSSIBLE.
LIGHTER AMOUNTS IN THE LOWER ELEVATIONS UP TO AN INCH WILL BE
POSSIBLE FOR AREAS SOUTHEAST OF A LINE FROM INEZ TO HAZARD...TO
BARBOURVILLE. WHILE SNOW IS EXPECTED ACROSS SOUTHEAST KENTUCKY...THE
REST OF EASTERN KENTUCKY MAY NOT SEE MUCH MORE THAN INCREASED CLOUD
COVER. PLAN TO GO AHEAD AND ISSUE AN SPS FOR OUR SOUTHEAST COUNTIES
TO ADDRESS THE POTENTIAL SNOWFALL. GIVEN THE EXPECTED CLOUD COVER
INTO WEDNESDAY...WENT WITH A PRETTY GOOD GRADIENT IN TEMPERATURES
FROM WEST TO EAST...WITH READINGS AROUND 50 IN THE WEST TO LOW AND
MID 30S IN THE EAST. PRECIPITATION WILL DEPART BY MIDDAY
WEDNESDAY...WITH TEMPORARY BREAK IN PRECIPITATION EXPECTED THROUGH
THE AFTERNOON AND EVENING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 307 AM EST TUE NOV 25 2014
THE MODELS BEGIN THE PERIOD IN PRETTY GOOD AGREEMENT...WITH A LARGE
SCALE UPPER LEVEL TROUGH OF LOW PRESSURE EJECTING OUT OF THE
NORTHERN PLAINS AND ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS
WEDNESDAY NIGHT THROUGH FRIDAY. IT APPEARS THAT THIS INITIAL SYSTEM
WILL BE FAIRLY PROGRESSIVE...SO ANY PRECIPITATION ASSOCIATED WITH IT
SHOULD BE SHORT LIVED AND NOT VERY HEAVY. A SHOT OF COLD AIR WILL
SPILL INTO THE REGION AS THE SYSTEM DEPARTS...WITH HIGHS ON THURSDAY
ONLY TOPPING OUT AROUND 40 DEGREES...AFTER MORNING LOWS IN THE UPPER
20S AND LOWER 30S. A RIDGE OF HIGH PRESSURE IS THEN PROGGED TO
BECOME ESTABLISHED ACROSS THE REGION TO BEGIN THE WEEKEND...WITH
WARMER TEMPERATURES AND PARTLY CLOUDY SKIES ON TAP FOR FRIDAY NIGHT
AND SATURDAY. SATURDAY COULD MARK THE START OF A SIGNIFICANT WARMING
TREND...WITH HIGHS POSSIBLY TOPPING OUT IN THE LOW TO MID 50S. THE
REGION IS EXPECTED TO WARM EVEN MORE ON SUNDAY AND MONDAY...AS THE
MERCURY CLIMBS INTO THE MID TO UPPER 50S FOR MOST LOCATIONS BOTH
DAYS. OVERNIGHT LOWS SATURDAY AND SUNDAY NIGHT WILL FEEL ALMOST
BALMY IF THEY IN FACT ONLY DROP INTO THE LOW TO MID 40S EACH NIGHT.
ENOUGH COLD AIR WILL LIKELY SPILL INTO THE REGION TO BEGIN THE
PERIOD TO ALLOW FOR SOME SNOW TO MIX WITH RAIN EARLY WEDNESDAY NIGHT
INTO THURSDAY MORNING ACROSS THE AREA. LITTLE IF ANY SNOW
ACCUMULATION IS EXPECTED. THE NEXT ROUND OF PRECIPITATION IS
EXPECTED TO MOVE ACROSS THE AREA BEGINNING SATURDAY NIGHT...AS A
WEAK FRONTAL BOUNDARY MOVES INTO AND STALLS OUT ACROSS THE AREA. THE
MODELS KEEP THE FRONT IN PLACE...AND THEREFORE THE THREAT OF
PRECIPITATION...THROUGH THE END OF THE DAY ON MONDAY. TEMPERATURES
DURING THIS PERIOD WILL REMAIN WARM ENOUGH FOR ANY PRECIPITATION
THAT OCCURS TO REMAIN IN LIQUID FORM. DUE TO SOME SMALL TIMING
DIFFERENCES BETWEEN THE MODELS REGARDING PRECIPITATION
ONSET...DURATION...AND AREAL COVERAGE...DECIDED TO GO WITH ONLY
CHANCE POPS AT THIS TIME. BASED ON THE LATEST MODEL DATA...THE FRONT
COULD EITHER REMAIN STALLED ACROSS THE AREA...ECMWF...OR DRIFT
SLOWLY NORTH AS A WEAK WARM FRONT...GFS...DURING THE MONDAY INTO
MONDAY NIGHT TIME FRAME. ONLY TIME WILL TELL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 621 AM EST TUE NOV 25 2014
VFR CONDITIONS WILL CONTINUE THROUGH THIS EVENING AS HIGH PRESSURE
PUSHES EAST ACROSS THE AREA. A DEVELOPING LOW PRESSURE SYSTEM WILL
SPREAD MOISTURE BACK INTO EASTERN KENTUCKY LATE TONIGHT...WITH CIGS
LOWERING. AS OF RIGHT NOW...LOOKS LIKE WE SHOULD SEE A GRADIENT IN
THE LOWER CIGS WITH THE LOWEST (IFR/MVFR) IN THE EAST...TRAILING
BACK TO VFR IN THE WEST. WE WILL ALSO SEE PRECIPITATION SPREAD INTO
THE AREA...MAINLY ACROSS SOUTHEASTERN KENTUCKY...WITH A MIX OF RAIN
AND SNOW...LIKELY BECOMING ALL SNOW. THIS WILL RESTRICT VISIBILITIES
BY LATE TONIGHT AS WELL...MAINLY AT KJKL AND KSJS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...KAS
LONG TERM...AR
AVIATION...KAS
AREA FORECAST DISCUSSION...CORRECTED
NWS JACKSON KY
308 AM EST TUE NOV 25 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 307 AM EST TUE NOV 25 2014
SURFACE RIDGING CONTINUES TO BUILD INTO EASTERN KENTUCKY THIS MORNING
WITH SKIES GENERALLY CLEAR TO MOSTLY CLEAR. THIS WILL HOLD THROUGH
THE DAY...PROVIDING A COOLER...BUT STILL RELATIVELY PLEASANT DAY. IN
FACT...WITH THE HELP OF THE SUNSHINE AND TEMPERATURES IN SOME PLACES
ALREADY IN THE 40S THIS MORNING...WE SHOULD HAVE NO PROBLEM
SURPASSING THE 50 DEGREE MARK THIS AFTERNOON. WITH AN ABUNDANCE OF LOW
LEVEL DRY AIR JUST OFF THE SURFACE...RAP AND HRRR ARE SUGGESTING
FAIRLY LOW DEWPOINTS THIS AFTERNOON...ESPECIALLY ACROSS SOUTHEAST
KENTUCKY. IT MIGHT BE A STRETCH TO FALL INTO THE TEENS...BUT
CERTAINLY DEWPOINTS DOWN INTO THE MID 20S WILL BE POSSIBLE. THIS WILL
PUT US CLOSE TO THE 25 PERCENT RH`S THIS AFTERNOON. I WOULDN`T BE
SURPRISED TO SEE A FEW SPOTS ACTUALLY REACH THIS VALUE...ESPECIALLY
IN SOUTHEAST KENTUCKY.
CLOUDS WILL BE ON THE INCREASE THIS EVENING AND ESPECIALLY TONIGHT.
MODELS HAVE AN AREA OF LOW PRESSURE DEVELOPING OVER FLORIDA AND
TRACKING NORTHWARD ALONG THE COAST TONIGHT. NEARLY ALL MODELS ARE IN
SUPPORT OF MOISTURE AND LIFT ASSOCIATED WITH THIS SYSTEM DEVELOPING
ACROSS FAR SOUTHEAST AND EAST KENTUCKY OVERNIGHT INTO WEDNESDAY
MORNING. GIVEN THE ABUNDANCE OF DRY AIR IN PLACE...WET BULB
TEMPERATURES WILL BE FAIRLY LOW. ASSUMING WE GET PRECIP RATES THAT
SUPPORT IT...WE SHOULD SEE PRIMARILY SNOW LATE TONIGHT INTO WEDNESDAY
MORNING...BUT SOME RAIN MAY BE POSSIBLE FARTHER INTO EASTERN KENTUCKY
WHERE PRECIP RATES MAY NOT BE AS HIGH. REGARDLESS...WE SHOULD SEE
TEMPERATURES COOL ENOUGH TO SUPPORT SOME LIGHT SNOW ACCUMULATION
ACROSS SOUTHEAST KENTUCKY. AT THIS TIME...THE HIGHEST AMOUNTS SHOULD
BE ABOVE 2500 FEET...WHERE 2 TO 3 INCHES OF SNOW MAY BE POSSIBLE.
LIGHTER AMOUNTS IN THE LOWER ELEVATIONS UP TO AN INCH WILL BE
POSSIBLE FOR AREAS SOUTHEAST OF A LINE FROM INEZ TO HAZARD...TO
BARBOURVILLE. WHILE SNOW IS EXPECTED ACROSS SOUTHEAST KENTUCKY...THE
REST OF EASTERN KENTUCKY MAY NOT SEE MUCH MORE THAN INCREASED CLOUD
COVER. PLAN TO GO AHEAD AND ISSUE AN SPS FOR OUR SOUTHEAST COUNTIES
TO ADDRESS THE POTENTIAL SNOWFALL. GIVEN THE EXPECTED CLOUD COVER
INTO WEDNESDAY...WENT WITH A PRETTY GOOD GRADIENT IN TEMPERATURES
FROM WEST TO EAST...WITH READINGS AROUND 50 IN THE WEST TO LOW AND
MID 30S IN THE EAST. PRECIPITATION WILL DEPART BY MIDDAY
WEDNESDAY...WITH TEMPORARY BREAK IN PRECIPITATION EXPECTED THROUGH
THE AFTERNOON AND EVENING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 307 AM EST TUE NOV 25 2014
THE MODELS BEGIN THE PERIOD IN PRETTY GOOD AGREEMENT...WITH A LARGE
SCALE UPPER LEVEL TROUGH OF LOW PRESSURE EJECTING OUT OF THE
NORTHERN PLAINS AND ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS
WEDNESDAY NIGHT THROUGH FRIDAY. IT APPEARS THAT THIS INITIAL SYSTEM
WILL BE FAIRLY PROGRESSIVE...SO ANY PRECIPITATION ASSOCIATED WITH IT
SHOULD BE SHORT LIVED AND NOT VERY HEAVY. A SHOT OF COLD AIR WILL
SPILL INTO THE REGION AS THE SYSTEM DEPARTS...WITH HIGHS ON THURSDAY
ONLY TOPPING OUT AROUND 40 DEGREES...AFTER MORNING LOWS IN THE UPPER
20S AND LOWER 30S. A RIDGE OF HIGH PRESSURE IS THEN PROGGED TO
BECOME ESTABLISHED ACROSS THE REGION TO BEGIN THE WEEKEND...WITH
WARMER TEMPERATURES AND PARTLY CLOUDY SKIES ON TAP FOR FRIDAY NIGHT
AND SATURDAY. SATURDAY COULD MARK THE START OF A SIGNIFICANT WARMING
TREND...WITH HIGHS POSSIBLY TOPPING OUT IN THE LOW TO MID 50S. THE
REGION IS EXPECTED TO WARM EVEN MORE ON SUNDAY AND MONDAY...AS THE
MERCURY CLIMBS INTO THE MID TO UPPER 50S FOR MOST LOCATIONS BOTH
DAYS. OVERNIGHT LOWS SATURDAY AND SUNDAY NIGHT WILL FEEL ALMOST
BALMY IF THEY IN FACT ONLY DROP INTO THE LOW TO MID 40S EACH NIGHT.
ENOUGH COLD AIR WILL LIKELY SPILL INTO THE REGION TO BEGIN THE
PERIOD TO ALLOW FOR SOME SNOW TO MIX WITH RAIN EARLY WEDNESDAY NIGHT
INTO THURSDAY MORNING ACROSS THE AREA. LITTLE IF ANY SNOW
ACCUMULATION IS EXPECTED. THE NEXT ROUND OF PRECIPITATION IS
EXPECTED TO MOVE ACROSS THE AREA BEGINNING SATURDAY NIGHT...AS A
WEAK FRONTAL BOUNDARY MOVES INTO AND STALLS OUT ACROSS THE AREA. THE
MODELS KEEP THE FRONT IN PLACE...AND THEREFORE THE THREAT OF
PRECIPITATION...THROUGH THE END OF THE DAY ON MONDAY. TEMPERATURES
DURING THIS PERIOD WILL REMAIN WARM ENOUGH FOR ANY PRECIPITATION
THAT OCCURS TO REMAIN IN LIQUID FORM. DUE TO SOME SMALL TIMING
DIFFERENCES BETWEEN THE MODELS REGARDING PRECIPITATION
ONSET...DURATION...AND AREAL COVERAGE...DECIDED TO GO WITH ONLY
CHANCE POPS AT THIS TIME. BASED ON THE LATEST MODEL DATA...THE FRONT
COULD EITHER REMAIN STALLED ACROSS THE AREA...ECMWF...OR DRIFT
SLOWLY NORTH AS A WEAK WARM FRONT...GFS...DURING THE MONDAY INTO
MONDAY NIGHT TIME FRAME. ONLY TIME WILL TELL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1232 AM EST TUE NOV 25 2014
VFR CONDITIONS WILL CONTINUE THROUGH THE NEXT 24 HOURS AS HIGH
PRESSURE SETS UP OVERHEAD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KAS
LONG TERM...AR
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1233 AM EST TUE NOV 25 2014
.UPDATE...
ISSUED AT 1232 AM EST TUE NOV 25 2014
UPDATED TO SLOW DOWN THE TEMPERATURE FALL OVERNIGHT AS WINDS HAVE
STAYED UP A BIT ALLOWING FOR A SLOWER OVERALL DECREASE. IN
FACT...TEMPERATURES MAY NOT REACH THE EXPECTED LOWS ACROSS MUCH OF
THE AREA GIVEN THE ADDED WIND. THUS...HAVE UPDATED TO INCREASE LOWS A
TAD. ALSO UPDATED SKY COVER TO REFLECT LESS IN THE WEST AND KEEPING
SOME PARTLY CLOUDY CONDITIONS IN THE EAST WITH THE HIGH CLOUDS
STREAMING NORTHWARD. UPDATED FORECAST HAS BEEN SENT.
UPDATE ISSUED AT 944 PM EST MON NOV 24 2014
CURRENT CONDITIONS ACROSS THE AREA FEATURE SOME LOW LEVEL CLOUD COVER
MOVING INTO CENTRAL KENTUCKY. THIS IS ASSOCIATED WITH A NEARLY
STATIONARY LOW OVER THE GREAT LAKES AND A WEAK SURFACE TROUGH IS
BRINGING SOME LOW LEVEL MOISTURE INTO THE AREA. THE BULK OF THIS
CLOUD COVER IS NOT EXPECTED TO MOVE INTO FAR EASTERN KENTUCKY AND
ADJUSTED THE FORECAST TO HAVE THE BULK OF THE CLOUD COVER EXIT THE
AREA TO THE NORTHEAST BY THE MORNING. THE OTHER CONCERN WAS THE
TEMPERATURES ACROSS THE AREA. TEMPS REMAIN QUITE WARM AND THE COOLER
AIR IS SLOW TO FILTER INTO THE AREA. IN FACT SOME GUSTY NORTHWEST
WINDS ARE STILL OCCURRING. HAVE UPDATED THE FORECAST TO HIGHLIGHT
THESE CHANGES. A NEW ZFP HAS BEEN ISSUED.
UPDATE ISSUED AT 651 PM EST MON NOV 24 2014
THE COLD FRONT AND ASSOCIATED LOW PRESSURE SYSTEM CONTINUE TO TRACK
OFF TO THE NORTHEAST THIS EVENING. WITH THIS A LESSENING GRADIENT IS
OCCURRING AND WINDS HAVE REALLY LESSENED ACROSS THE AREA. THOUGH A FEW
20 TO 25 MPH GUSTS ARE STILL POSSIBLE...HAVE DECIDED TO CANCEL THE
WIND ADVISORY AN HOUR EARLY. THIS IS ALSO LINING UP WITH
COLLABORATION WITH NEIGHBORING OFFICES AS WELL. OTHERWISE...DROPPING
TEMPS THIS EVENING WITH COLDER AIR MOVING INTO THE AREA WILL CONTINUE
AND THE CURRENT FORECAST HAS THIS IN CHECK. WILL LET THE OTHER
PARAMETERS OF THE FORECAST RIDE BUT WILL SEND OUT A NEW ZFP TO TAKE
OUT THE NPW.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 325 PM EST MON NOV 24 2014
19Z SFC ANALYSIS SHOWS A DEEP AREA OF LOW PRESSURE MOVING NORTHEAST
AWAY FROM THE GREAT LAKES. FROM THIS...A STRONG...BUT NOW DRY...COLD
FRONT IS PRESSING THROUGH EAST KENTUCKY. AHEAD OF THIS BOUNDARY...
STRONG SOUTHWEST WINDS ARE GUSTING ROUTINELY INTO THE 35 TO 45 MPH
RANGE WITH A FEW GUSTS EXCEEDING 50 MPH. THE OFFICE HAS RECEIVED
NUMEROUS REPORTS OF TREE DAMAGE AND POWER OUTAGES DUE TO THE WINDS.
THESE WINDS HAVE ALSO SUPPORTED TEMPERATURES IN THE UPPER 60S AND
LOWER 70S WITH DEWPOINTS IN THE MID 40S FOR MUCH OF THE AFTERNOON AND
THEY REMAIN THERE IN FAR EASTERN KENTUCKY. HOWEVER...ON THE OTHER
SIDE OF THE BOUNDARY THE WINDS REMAIN SOUTHWEST BUT ARE NOT QUITE AS
STRONG AND ARE BRINGING IN A DIFFERENT AIR MASS. AS SUCH...
TEMPERATURES DROPPING THROUGH THE 50S ARE NOW REACHING THE WESTERN
EXTENT OF THE CWA ALONG WITH DEWPOINTS HEADED FOR THE 30S. THE WINDS
REMAIN AT ADVISORY LEVEL IN THE EAST BUT ARE NOT QUITE THERE IN THE
WEST. AS THEY FURTHER SETTLE WE WILL LIKELY BE ABLE TO DROP THE
ADVISORY EARLY. FOR NOW...THOUGH...WILL CONTINUE TO LET IT RIDE FOR
THE ENTIRE CWA THROUGH 00Z.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE DEEP...AND FULL-
LATITUDE...TROUGH CROSSING THE OHIO VALLEY AND GREAT LAKES TODAY INTO
TUESDAY. HOWEVER...A SOUTHWESTERN EXTENT OF THE LARGER TROUGH WILL
REMAIN STRETCHED INTO SOUTHWESTERN TEXAS AND IT IS THIS SECTION
THAT TIGHTENS UP AND MOVES EAST LATER TUESDAY. THE SOUTHERN
ENERGY...IN CONJUNCTION WITH SOME MOVING THROUGH THE MID MISSISSIPPI
VALLEY WILL SWEEP THROUGH THE DEEP SOUTH AND ACROSS THE TENNESSEE
VALLEY ON TUESDAY NIGHT. OF NOTE ALSO...A CLUSTER OF ENERGY WILL BE
RIDING SOUTHEAST THROUGH THE CENTRAL PLAINS AT DAWN WEDNESDAY. WITH
THE MODEL AGREEMENT HAVE FAVORED THE NAM12 AND HRRR INITIALLY AND
THEN A BLEND OF THE ECMWF AND NAM12 FOR WX DETAILS INTO WEDNESDAY
MORNING.
SENSIBLE WEATHER WILL FEATURE WINDS SETTLING DOWN THIS EVENING FROM
WEST TO EAST AS THE GRADIENT RELAXES. IT WILL ALSO MEAN A COOLER
EVENING...BUT NOWHERE NEAR AS COLD AS IT HAS BEEN OF LATE. TUESDAY
WILL CERTAINLY BE A COOLER DAY BUT A QUIETER ONE AS WE WILL BE
BETWEEN SYSTEMS. A DEVELOPING SFC LOW ALONG THE SOUTHEAST COAST WILL
START TO SPREAD HIGH CLOUDS INTO THE AREA FROM THE SOUTHEAST BY
EVENING. LOOK FOR THESE TO THICKEN AND LOWER WITH TIME THAT NIGHT AS
THE SOUTHEAST PORTION OF THE CWA IS BRUSHED BY THE PCPN SHIELD FROM
THIS NASCENT COASTAL SYSTEM. HAVE CONTINUED THE THREAT OF RAIN OR
SNOW PRIMARILY IN THE COUNTIES BORDERING VIRGINIA...BUT NOT
ANTICIPATING MUCH IN THE WAY OF ACCUMULATIONS EXCEPT PERHAPS A TOUCH
OF IT JUST ON THE PEAK OF BLACK MOUNTAIN.
USED THE BCCONSSHORT AS A STARTING POINT FOR T/TD/WINDS THROUGH THE
NEXT 24 HOURS AND THE SUPERBLEND THEREAFTER. DID MAKE SOME MINOR
TERRAIN BASED ADJUSTMENTS TONIGHT AND TUESDAY NIGHT TO THE LOWS. AS
FOR POPS...ENDED UP CLOSE TO A BLEND OF THE MAV AND MET NUMBERS FOR
TUESDAY NIGHT AND DRY OTHERWISE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 332 PM EST MON NOV 24 2014
THERE WILL BE A DEVELOPING SURFACE LOW OFF THE CAROLINA COAST BEGINNING
THE PERIOD AND THE FRONTOGENESIS IS AIDED BY A BROAD TROUGH/EMBEDDED
SHORTWAVE ENERGY SWING THROUGH THE EASTERN U.S. THOROUGH THE PERIOD.
THIS COASTAL LOW IS EXPECTED TO MOVE NE ALONG THE ATLANTIC SEABOARD
WEDNESDAY INTO THURSDAY. ANOTHER EMBEDDED SHORTWAVE WILL EXIT THE
UPPER PLAINS AND DROP SE INTO THE OHIO AND TENNESSEE VALLEYS
WEDNESDAY NIGHT INTO THURSDAY. SURFACE HIGH WILL BUILD EAST LATER
THURSDAY INTO FRIDAY. UPPER LEVELS WILL BEGIN TO BECOME MORE ZONAL
WITH SURFACE FRONT DEVELOPING ACROSS PORTIONS OF THE OHIO VALLEY
GOING INTO SUNDAY INTO MONDAY.
SENSIBLE WEATHER... GIVEN SYNOPTIC SETUP LOW PRESSURE MOVING ALONG
THE ATLANTIC COAST COULD BRING SLIGHT TO CHANCES MAINLY RAIN/SNOW
SHOWERS ACROSS THE EASTERN AND SOUTHEASTERN PORTIONS OF THE REGION
EARLY WEDNESDAY...BEFORE TRANSITIONING TO RAIN SHOWERS THROUGH THE
DAY WEDNESDAY. THIS LOW WILL TRACK NORTH AND EAST WHILE AFOREMENTIONED
DISTURBANCE DROPS SE ACROSS THE REGION WEDNESDAY NIGHT. THERE IS
BETTER AGREEMENT WITH MODELS SO DID OPT TO BRING POPS UP A BIT FOR
THIS SYSTEM. THIS SYSTEM IS EXPECTED TO BRING SLIGHT TO CHANCE
RAIN/SNOW SHOWERS ACROSS EASTERN KY WEDNESDAY NIGHT. THURSDAY MUCH OF
THE REGION WILL WARM UP SO EXPECT MOST OF THE ACTIVITY WILL
TRANSITION TO RAIN SHOWERS BEFORE EXITING THE REGION LATE IN THE DAY
ON THURSDAY. AFTER THIS IT IS EXPECTED TO BE QUIET AND MOSTLY CLEAR
CONDITIONS TIL WE GET TO THE SATURDAY TIME FRAME. DURING THIS TIME
MODELS ARE NOT IN GOOD AGREEMENT ON TIMING/DEVELOPMENT OF NEXT
SYSTEM. RIGHT NOW THINKING WILL ONLY GO WITH SLIGHT CHANCES OF RAIN
SHOWERS SATURDAY...THEN TRANSITION TO SLIGHT/CHANCE RAINS SHOWERS AS
FRONT SLOW PROGRESSES SOUTH ACROSS THE REGION GOING INTO SUNDAY AND
MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1232 AM EST TUE NOV 25 2014
VFR CONDITIONS WILL CONTINUE THROUGH THE NEXT 24 HOURS AS HIGH
PRESSURE SETS UP OVERHEAD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KAS
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...KAS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
640 PM EST WED NOV 26 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 510 PM EST WED NOV 26 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS CONTINUE TO SHOW AN AMPLIFIED
PATTERN ACROSS NAMERICA WITH A RIDGE ALONG/JUST OFF THE W COAST...A
TROF EXTENDING FROM NCNTRL CANADA TO THE GULF OF MEXICO AND A RIDGE
OVER THE WRN ATLANTIC. A SHORTWAVE TROF SWINGING SE THRU NRN
ONTARIO/NRN MN IS PRODUCING SOME -SN FROM NW WI ACROSS WRN UPPER MI
INTO NRN ONTARIO. AT THE SFC...SHARPENING TROF RUNS FROM NEAR KIWD
TO JUST S OF KCMX AND THEN NE ACROSS ERN LAKE SUPERIOR. MDT TO HVY
LAKE ENHANCED SNOW IS SPREADING INTO WRN UPPER MI IN ASSOCIATION
WITH THE TROF. OFF TO THE NW...STRONG SFC HIGH PRES ACROSS
MANITOBA/SASKATCHEWAN IS BUILDING S AND E INTO THE NRN PLAINS.
PERIOD OF LAKE ENHANCED SNOW IS EXPECTED TONIGHT UNDER HEIGHT
FALLS/DEEP LAYER QVECTOR CONVERGENCE WITH SHORTWAVE SWINGING ACROSS
THE UPPER LAKES. BEST...MOST PERSISTENT LOW-LEVEL CONVERGENCE IS
INDICATED OVER THE FAR W. SO...MOST SUSTAINED MDT TO AT TIMES HVY
SNOW WILL OCCUR OVER THE FAR W FROM THE PORCUPINE MTNS TO KIWD. WITH
DGZ FALLING INTO THE LOW-LEVELS WHERE UPWARD MOTION IS FOCUSED...
EXPECT SNOW TO WATER RATIOS TO INCREASE INTO THE 20-30 TO 1 RANGE
TONIGHT. A LITTLE CONCERNED THAT THE UPWARD MOTION IS ONLY DEPICTED
IN THE LOWEST LEVELS THIS EVENING...SUGGESTING LITTLE OVERALL
SYNOPTIC SUPPORT WITH PASSING SHORTWAVE. THIS MAY TEND TO LIMIT
COVERAGE OF HVY SNOW TO ONLY THE AREAS WHERE LOW-LEVEL CONVERGENCE
IS FOCUSED. AS IT STANDS NOW...SITUATION APPEARS TO BE A MARGINAL
WARNING EVENT WITH WARNING THRESHOLDS ONLY POTENTIALLY BEING MET IN
A FEW LOCALIZED AREAS (8 INCHES OR MORE IN 12HRS OR 12 OR MORE IN
24HRS). LARGE PORTIONS OF ONTONAGON/GOGEBIC COUNTIES WILL PROBABLY
FALL IN THE 4 TO 7 INCH SNOWFALL RANGE. OF NOTE...THERE IS A FAIRLY
CONSISTENT SIGNAL AMONG MOST OF THE HIGH RES MODEL GUIDANCE FOR THE
HEAVIEST SNOW TO AFFECT LOCATIONS JUST W OF KIWD. WILL BE
INTERESTING TO SEE IF THAT INDEED DOES HAPPEN. OVER THE KEWEENAW...
SNOWFALL HAS NOT BEEN ESPECIALLY NOTEWORTHY WITH SFC TROF PASSAGE
WHICH IS WHEN THE HEAVIEST SNOWFALL WOULD LIKELY OCCUR. WITH A
DECENT LOW-LEVEL CONVERGENCE SIGNAL LACKING TONIGHT...CONSIDERED
DROPPING ADVY...BUT WILL HOLD OFF FOR NOW WITH POTENTIAL FOR SNOW TO
STILL PICK UP FOR A TIME THIS EVENING DURING THE PERIOD OF SYNOPTIC
FORCING. TO THE E...LONGER FETCH/BETTER TERRAIN ENHANCEMENT WILL
LEAD TO ANOTHER AREA OF HEAVIER SNOW DEVELOPING OVER NCNTRL UPPER MI
SPREADING FROM BARAGA COUNTY/FAR NRN MARQUETTE COUNTY EARLY THIS
EVENING TO ALGER COUNTY LATE EVENING. LOOKS LIKE SOLID ADVY AMOUNTS
FROM THE HURON MTNS TO NEGAUNEE AND EAST INTO WRN ALGER COUNTY.
POTENTIAL IS THERE FOR LOCALIZED WARNING AMOUNTS GIVEN THE
INCREASING SNOW TO WATER RATIOS AND THE LIKLIHOOD OF A LAKE NIPIGON
INITIATED DOMINANT BAND LATER TONIGHT INTO THE MORNING HRS THAT
WOULD LIKELY IMPACT LOCATIONS SOMEWHERE FROM AROUND BIG
BAY/MARQUETTE TO AROUND THE SHOT POINT AREA. IF SUCH A BAND DOES
DEVELOP AND BECOME STATIONARY FOR SEVERAL HRS...WARNING AMOUNTS MAY
BE ACHIEVED. BLSN WILL ALSO BE AN ISSUE IN THE OPEN AREAS ALONG LAKE
SUPERIOR WHERE WINDS WILL GUST OVER 30 MPH. WHILE THERE MAY BE A
BRIEF PERIOD OF HEAVIER SNOW OVER LUCE COUNTY WITH TROF PASSAGE...
SETUP AFTER TROF PASSAGE IS NOT FAVORABLE FOR ADVY SNOWFALL AMOUNTS
IN THAT AREA. ACROSS THE REST OF THE AREA...EXPECT SOME -SN FOR A
TIME TONIGHT. SOME OF THE LES OFF LAKE SUPERIOR WILL REACH NRN DELTA
AND SRN SCHOOLCRAFT COUNTIES TO PROVIDE AN INCH OR TWO OF SNOWFALL.
ON THANKSGIVING DAY...FCST SOUNDINGS SHOW INVERSIONS AT A LOW 4KFT
TO START THE DAY. LOW-LEVEL FLOW TRENDS ANTICYCLONIC DURING THE
DAY...ESPECIALLY SO OVER WRN LAKE SUPERIOR AS SFC HIGH PRES RIDGE
WILL EXTEND FROM THE MID MISSISSIPPI VALLEY N THRU WRN UPPER MI/WRN
LAKE SUPERIOR BY 00Z FRI. THESE 2 FACTORS COMBINED WITH RISING
HEIGHTS/LARGE SCALE SUBSIDENCE/QVECTOR DIVERGENCE WILL LIMIT LES
INTENSITY AND WILL RESULT IN LES DIMINISHING FROM W TO E THRU THE
DAY. IN FACT OVER THE FAR W...LES WILL END LATE IN THE AFTN AROUND
KIWD AS FLOW BACKS SW. THE ONE POSTIVE FACTOR FOR THE LES ON
THANKSGIVING DAY IS THAT THE DGZ WILL OCCUPY MOST OF THE CONVECTIVE
LAYER TO FLUFF UP SNOW ACCUMULATIONS. SO...DESPITE THE NEGATIVES
LEADING TO MOSTLY LIGHT LES ON THE WHOLE...MIGHT BE ABLE TO FLUFF UP
3-4 INCHES OF SNOW WHERE LES IS MOST PERSISTENT. THE GREATEST
ACCUMULATIONS WILL OCCUR E OF MARQUETTE WHERE LOW-LEVEL FLOW IS MORE
CYCLONIC THRU THE EARLY PART OF THE DAY AND WHERE LAKE NIPIGON
PRECONDITIONING WILL COME INTO PLAY. AWAY FROM THE MAIN LES...
SCT -SHSN/FLURRIES ARE POSSIBLE AT TIMES...EXCEPT OVER THE FAR
SCNTRL. TEMPS WILL BE UNSEASONABLY COLD ON THANKSGIVING DAY AS 850MB
THERMAL TROF (AROUND -20C) PASSES ACROSS THE AREA. EXPECT HIGHS
MOSTLY IN THE LOW/MID TEENS...TO AROUND 20F ALONG LAKE SUPERIOR AND
E. RECORD LOW MAX TEMP OF 18F HERE AT NWS MQT WILL FALL. IF TEMP
DOESN`T REACH 14F...IT WILL BE THE COLDEST MAX TEMP FOR SO EARLY IN
THE SEASON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM EST WED NOV 26 2014
THU NIGHT...THE LINGERING LES WILL DIMINISH AS THE SFC RIDGE AXIS
SLIDES THROUGH THE WRN LAKES AND LOW LEVEL WINDS BACK TO THE SW.
WITH LIGHT WINDS AND A PERIOD OF CLEARING OVER THE INTERIOR WEST
DURING THE EVENING...TEMPS WILL DROP QUICKLY TO MINS BELOW GUIDANCE
BEFORE RECOVERING OVERNIGHT AS CLOUDS MOVE IN. MODELS WERE
CONSISTENT IN BRINGING POTENTIAL FOR SOME LIGHT SNOW INTO THE WEST
LATE WITH THE DEVELOPING WAA PATTERN.
FRI...SNOW IS EXPECTED TO SPREAD ACROSS THE REGION WITH FAVORABLE
MOISTURE ADVECTION AND ISENTROPIC LIFT THROUGH THE 850-700 MB
FRONTAL ZONE. 3 G/KG MOISTURE AVAILABLE IN THE 285K-295K LAYER
DURING THE PERIOD OF STRONGEST LIFT IS CONSISTENT WITH POTENTIAL FOR
2 TO 4 INCHES OF SNOW WITH MODELS CONSENSUS QPF OF 0.10 TO 0.20
INCHES AND SLR VALUES FROM AROUND 15/1-20/1. THERE IS STILL SOME
UNCERTAINTY WHERE THE BAND OF HEAVIER SNOW WILL DEVELOP AS THE 12Z
NAM BRINGS GREATER AMOUNTS OF PCPN INTO SRN UPPER MI COMPARED TO THE
GFS AND ECMWF. THERE WILL ALSO BE THE POTENTIAL FOR A BAND OF LAKE
ENHANCED SNOW OFF OF LAKE MI THAT COULD SPREAD EASTWARD FROM NEAR
THE GARDEN PENINSULA INTO LUCE COUNTY. SINCE THE STRONGEST LOW
LEVEL CONV IS EXPECTED TO MOVE STEADILY TO THE EAST...SNOW AMOUNTS
IN ANY ONE LOCATION SHOULD BE LIMITED. HOWEVER...CONFIDENCE IS LOWER
FOR THE POSITION/STRENGTH OF THIS FEATURE THAT COULD ADD SEVERAL
INCHES TO THE SNOW TOTALS.
FRI NIGHT INTO SAT...SFC LOW PRES IS FCST TO SPREAD FROM THE NRN
PLAINS TO THE UPPER MS VALLEY WITH CONTINUED WAA BRINGING
SUBSTANTIAL 850 MB WARMING. NAM/GFS 285-295K ISENTROPIC PROGS
SUGGEST THAT THE STRONGEST LIFT AND DEEPEST MOISTURE WILL REMAIN
ACROSS LAKE SUPERIOR AND FAR NRN UPPER MI. WITH A PROMINENT 850-700
MB DRY LAYER DEVELOPING TO THE SOUTH...FREEZING DRIZZLE WILL BE
POSSIBLE ALONG WITH SOME LIGHT SNOW OR FLURRIES AS ICE NUCLEI BECOME
MORE SCARCE. ANY PCPN AMOUNTS ARE EXPECTED TO BE LIGHT WITH
ONLY A FEW HUNDREDTHS OF AN INCH AT MOST. THERE MAY ALSO BE ENOUGH
900-700 MB WARMING INTO THE AREA OF DEEPER MOISTURE FOR SOME
FZRA.
SAT NIGHT AND SUN...LOW PRES LIFTING NE TOWARD JAMES BAY SAT NIGHT
WILL DRAG A COLD FRONT THROUGH THE NRN LAKES WITH MUCH COLDER AIR
MOVING IN ON NW WINDS. WITH 850 MB TEMPS FALLING TO NEAR -18C...LES
WILL BE LIKELY FOR NW WIND SNOW BELTS. A LIMITING FACTOR FOR HEAVIER
SNOW WILL BE SUBSTANTIAL 850-700 MB DRYING WITH BACKING AND
INCREASING ACYC LOW LEVEL WINDS FROM LATE SUN INTO SUN NIGHT.
MON-WED...THE GFS/GEFS AND ECMWF WERE IN REASONABLE AGREEMENT WITH
THE PATTERN INTO NEXT WEEK WITH HIGH PRES BUILDING INTO THE REGION
MON INTO MON NIGHT BRINGING DIMINISHING LES. ANOTHER MID LEVEL AND
SFC TROUGH MOVING THROUGH TUE INTO TUE NIGHT COULD BRING SOME LIGHT
SNOW TO THE AREA. THE MODELS HAVE TRENDED TOWARD KEEPING COLDER
ACROSS REGION THAT WOULD KEEP ANY PCPN AS SNOW WITH MAX TEMPS
RECOVERING INTO THE MID 20S TO AROUND 30 BY TUE AND WED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 639 PM EST WED NOV 26 2014
PERIODS OF HEAVIER LK EFFECT SN AND AT LEAST OCNL LIFR CONDITIONS
ASSOCIATED WITH THE PASSAGE OF A LO PRES TROF AND WSHFT TO A FVRBL
UPSLOPE N DIRECTION WL IMPACT MAINLY IWD AND SAW INTO THE EARLY MRNG
HRS ON THANKSGIVING BEFORE THE ARRIVAL OF LARGE SCALE SUBSIDENCE/
DRYING BEHIND THE TROF RESULTS IN A STEADY IMPROVEMENT LATER TNGT/
THU MRNG. SINCE THE N WIND IS NOT A FAVORABLE WIND FOR CMX...MVFR/
ONLY OCNL IFR VSBYS WL BE THE RULE AT THAT TERMINAL. GUSTY N WINDS
RIGHT BEHIND THE TROF PASSAGE WL ALSO DIMINISH LATER TNGT/EARLY THU
MRNG UNDER WEAKENING PRES GRADIENT ASSOCIATED WITH SLOWLY APRCHG HI
PRES RDG. AS THE HI AND ACCOMPANYING DRIER AIR EDGE CLOSER ON
THANKSGIVING...THE LLVL WINDS WL BACK TOWARD THE NW AND THEN THE
W... RESULTING IN A RETURN TO VFR CONDITIONS AT IWD AND SAW. BUT
MORE UPSLOPE WIND AT CMX MAY HOLD CIGS IN THE MVFR RANGE AT THAT
LOCATION THRU THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 PM EST WED NOV 26 2014
A SFC TROUGH WILL SLIDE SOUTH OVER LAKE SUPERIOR TONIGHT.
BEHIND THE TROUGH...EXPECT NORTHERLY WINDS TO 30 KTS. WINDS WILL
THEN DIMINISH TO UNDER 20 KT W TO E THU/THU NIGHT AS HIGH PRES RIDGE
ARRIVES. WITH ANOTHER COLD FRONT PUSHING ACROSS THE UPPER LAKES SAT
NIGHT...EXPECT INCREASING S/SW WINDS TO 15-25KT FRI INTO SAT AHEAD
OF FRONT. BEHIND THE FRONT...NW WINDS MAY REACH 20-30KT LATE SAT
NIGHT AND SUN AND INCREASE TO GALES BY SUN NIGHT INTO MON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 10 PM THIS EVENING TO 1 PM EST
THURSDAY FOR MIZ006.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THURSDAY FOR MIZ004.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THURSDAY FOR MIZ005.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ THURSDAY FOR
MIZ002-009.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THURSDAY FOR MIZ001-003.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
638 PM EST WED NOV 26 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 510 PM EST WED NOV 26 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS CONTINUE TO SHOW AN AMPLIFIED
PATTERN ACROSS NAMERICA WITH A RIDGE ALONG/JUST OFF THE W COAST...A
TROF EXTENDING FROM NCNTRL CANADA TO THE GULF OF MEXICO AND A RIDGE
OVER THE WRN ATLANTIC. A SHORTWAVE TROF SWINGING SE THRU NRN
ONTARIO/NRN MN IS PRODUCING SOME -SN FROM NW WI ACROSS WRN UPPER MI
INTO NRN ONTARIO. AT THE SFC...SHARPENING TROF RUNS FROM NEAR KIWD
TO JUST S OF KCMX AND THEN NE ACROSS ERN LAKE SUPERIOR. MDT TO HVY
LAKE ENHANCED SNOW IS SPREADING INTO WRN UPPER MI IN ASSOCIATION
WITH THE TROF. OFF TO THE NW...STRONG SFC HIGH PRES ACROSS
MANITOBA/SASKATCHEWAN IS BUILDING S AND E INTO THE NRN PLAINS.
PERIOD OF LAKE ENHANCED SNOW IS EXPECTED TONIGHT UNDER HEIGHT
FALLS/DEEP LAYER QVECTOR CONVERGENCE WITH SHORTWAVE SWINGING ACROSS
THE UPPER LAKES. BEST...MOST PERSISTENT LOW-LEVEL CONVERGENCE IS
INDICATED OVER THE FAR W. SO...MOST SUSTAINED MDT TO AT TIMES HVY
SNOW WILL OCCUR OVER THE FAR W FROM THE PORCUPINE MTNS TO KIWD. WITH
DGZ FALLING INTO THE LOW-LEVELS WHERE UPWARD MOTION IS FOCUSED...
EXPECT SNOW TO WATER RATIOS TO INCREASE INTO THE 20-30 TO 1 RANGE
TONIGHT. A LITTLE CONCERNED THAT THE UPWARD MOTION IS ONLY DEPICTED
IN THE LOWEST LEVELS THIS EVENING...SUGGESTING LITTLE OVERALL
SYNOPTIC SUPPORT WITH PASSING SHORTWAVE. THIS MAY TEND TO LIMIT
COVERAGE OF HVY SNOW TO ONLY THE AREAS WHERE LOW-LEVEL CONVERGENCE
IS FOCUSED. AS IT STANDS NOW...SITUATION APPEARS TO BE A MARGINAL
WARNING EVENT WITH WARNING THRESHOLDS ONLY POTENTIALLY BEING MET IN
A FEW LOCALIZED AREAS (8 INCHES OR MORE IN 12HRS OR 12 OR MORE IN
24HRS). LARGE PORTIONS OF ONTONAGON/GOGEBIC COUNTIES WILL PROBABLY
FALL IN THE 4 TO 7 INCH SNOWFALL RANGE. OF NOTE...THERE IS A FAIRLY
CONSISTENT SIGNAL AMONG MOST OF THE HIGH RES MODEL GUIDANCE FOR THE
HEAVIEST SNOW TO AFFECT LOCATIONS JUST W OF KIWD. WILL BE
INTERESTING TO SEE IF THAT INDEED DOES HAPPEN. OVER THE KEWEENAW...
SNOWFALL HAS NOT BEEN ESPECIALLY NOTEWORTHY WITH SFC TROF PASSAGE
WHICH IS WHEN THE HEAVIEST SNOWFALL WOULD LIKELY OCCUR. WITH A
DECENT LOW-LEVEL CONVERGENCE SIGNAL LACKING TONIGHT...CONSIDERED
DROPPING ADVY...BUT WILL HOLD OFF FOR NOW WITH POTENTIAL FOR SNOW TO
STILL PICK UP FOR A TIME THIS EVENING DURING THE PERIOD OF SYNOPTIC
FORCING. TO THE E...LONGER FETCH/BETTER TERRAIN ENHANCEMENT WILL
LEAD TO ANOTHER AREA OF HEAVIER SNOW DEVELOPING OVER NCNTRL UPPER MI
SPREADING FROM BARAGA COUNTY/FAR NRN MARQUETTE COUNTY EARLY THIS
EVENING TO ALGER COUNTY LATE EVENING. LOOKS LIKE SOLID ADVY AMOUNTS
FROM THE HURON MTNS TO NEGAUNEE AND EAST INTO WRN ALGER COUNTY.
POTENTIAL IS THERE FOR LOCALIZED WARNING AMOUNTS GIVEN THE
INCREASING SNOW TO WATER RATIOS AND THE LIKLIHOOD OF A LAKE NIPIGON
INITIATED DOMINANT BAND LATER TONIGHT INTO THE MORNING HRS THAT
WOULD LIKELY IMPACT LOCATIONS SOMEWHERE FROM AROUND BIG
BAY/MARQUETTE TO AROUND THE SHOT POINT AREA. IF SUCH A BAND DOES
DEVELOP AND BECOME STATIONARY FOR SEVERAL HRS...WARNING AMOUNTS MAY
BE ACHIEVED. BLSN WILL ALSO BE AN ISSUE IN THE OPEN AREAS ALONG LAKE
SUPERIOR WHERE WINDS WILL GUST OVER 30 MPH. WHILE THERE MAY BE A
BRIEF PERIOD OF HEAVIER SNOW OVER LUCE COUNTY WITH TROF PASSAGE...
SETUP AFTER TROF PASSAGE IS NOT FAVORABLE FOR ADVY SNOWFALL AMOUNTS
IN THAT AREA. ACROSS THE REST OF THE AREA...EXPECT SOME -SN FOR A
TIME TONIGHT. SOME OF THE LES OFF LAKE SUPERIOR WILL REACH NRN DELTA
AND SRN SCHOOLCRAFT COUNTIES TO PROVIDE AN INCH OR TWO OF SNOWFALL.
ON THANKSGIVING DAY...FCST SOUNDINGS SHOW INVERSIONS AT A LOW 4KFT
TO START THE DAY. LOW-LEVEL FLOW TRENDS ANTICYCLONIC DURING THE
DAY...ESPECIALLY SO OVER WRN LAKE SUPERIOR AS SFC HIGH PRES RIDGE
WILL EXTEND FROM THE MID MISSISSIPPI VALLEY N THRU WRN UPPER MI/WRN
LAKE SUPERIOR BY 00Z FRI. THESE 2 FACTORS COMBINED WITH RISING
HEIGHTS/LARGE SCALE SUBSIDENCE/QVECTOR DIVERGENCE WILL LIMIT LES
INTENSITY AND WILL RESULT IN LES DIMINISHING FROM W TO E THRU THE
DAY. IN FACT OVER THE FAR W...LES WILL END LATE IN THE AFTN AROUND
KIWD AS FLOW BACKS SW. THE ONE POSTIVE FACTOR FOR THE LES ON
THANKSGIVING DAY IS THAT THE DGZ WILL OCCUPY MOST OF THE CONVECTIVE
LAYER TO FLUFF UP SNOW ACCUMULATIONS. SO...DESPITE THE NEGATIVES
LEADING TO MOSTLY LIGHT LES ON THE WHOLE...MIGHT BE ABLE TO FLUFF UP
3-4 INCHES OF SNOW WHERE LES IS MOST PERSISTENT. THE GREATEST
ACCUMULATIONS WILL OCCUR E OF MARQUETTE WHERE LOW-LEVEL FLOW IS MORE
CYCLONIC THRU THE EARLY PART OF THE DAY AND WHERE LAKE NIPIGON
PRECONDITIONING WILL COME INTO PLAY. AWAY FROM THE MAIN LES...
SCT -SHSN/FLURRIES ARE POSSIBLE AT TIMES...EXCEPT OVER THE FAR
SCNTRL. TEMPS WILL BE UNSEASONABLY COLD ON THANKSGIVING DAY AS 850MB
THERMAL TROF (AROUND -20C) PASSES ACROSS THE AREA. EXPECT HIGHS
MOSTLY IN THE LOW/MID TEENS...TO AROUND 20F ALONG LAKE SUPERIOR AND
E. RECORD LOW MAX TEMP OF 18F HERE AT NWS MQT WILL FALL. IF TEMP
DOESN`T REACH 14F...IT WILL BE THE COLDEST MAX TEMP FOR SO EARLY IN
THE SEASON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM EST WED NOV 26 2014
THU NIGHT...THE LINGERING LES WILL DIMINISH AS THE SFC RIDGE AXIS
SLIDES THROUGH THE WRN LAKES AND LOW LEVEL WINDS BACK TO THE SW.
WITH LIGHT WINDS AND A PERIOD OF CLEARING OVER THE INTERIOR WEST
DURING THE EVENING...TEMPS WILL DROP QUICKLY TO MINS BELOW GUIDANCE
BEFORE RECOVERING OVERNIGHT AS CLOUDS MOVE IN. MODELS WERE
CONSISTENT IN BRINGING POTENTIAL FOR SOME LIGHT SNOW INTO THE WEST
LATE WITH THE DEVELOPING WAA PATTERN.
FRI...SNOW IS EXPECTED TO SPREAD ACROSS THE REGION WITH FAVORABLE
MOISTURE ADVECTION AND ISENTROPIC LIFT THROUGH THE 850-700 MB
FRONTAL ZONE. 3 G/KG MOISTURE AVAILABLE IN THE 285K-295K LAYER
DURING THE PERIOD OF STRONGEST LIFT IS CONSISTENT WITH POTENTIAL FOR
2 TO 4 INCHES OF SNOW WITH MODELS CONSENSUS QPF OF 0.10 TO 0.20
INCHES AND SLR VALUES FROM AROUND 15/1-20/1. THERE IS STILL SOME
UNCERTAINTY WHERE THE BAND OF HEAVIER SNOW WILL DEVELOP AS THE 12Z
NAM BRINGS GREATER AMOUNTS OF PCPN INTO SRN UPPER MI COMPARED TO THE
GFS AND ECMWF. THERE WILL ALSO BE THE POTENTIAL FOR A BAND OF LAKE
ENHANCED SNOW OFF OF LAKE MI THAT COULD SPREAD EASTWARD FROM NEAR
THE GARDEN PENINSULA INTO LUCE COUNTY. SINCE THE STRONGEST LOW
LEVEL CONV IS EXPECTED TO MOVE STEADILY TO THE EAST...SNOW AMOUNTS
IN ANY ONE LOCATION SHOULD BE LIMITED. HOWEVER...CONFIDENCE IS LOWER
FOR THE POSITION/STRENGTH OF THIS FEATURE THAT COULD ADD SEVERAL
INCHES TO THE SNOW TOTALS.
FRI NIGHT INTO SAT...SFC LOW PRES IS FCST TO SPREAD FROM THE NRN
PLAINS TO THE UPPER MS VALLEY WITH CONTINUED WAA BRINGING
SUBSTANTIAL 850 MB WARMING. NAM/GFS 285-295K ISENTROPIC PROGS
SUGGEST THAT THE STRONGEST LIFT AND DEEPEST MOISTURE WILL REMAIN
ACROSS LAKE SUPERIOR AND FAR NRN UPPER MI. WITH A PROMINENT 850-700
MB DRY LAYER DEVELOPING TO THE SOUTH...FREEZING DRIZZLE WILL BE
POSSIBLE ALONG WITH SOME LIGHT SNOW OR FLURRIES AS ICE NUCLEI BECOME
MORE SCARCE. ANY PCPN AMOUNTS ARE EXPECTED TO BE LIGHT WITH
ONLY A FEW HUNDREDTHS OF AN INCH AT MOST. THERE MAY ALSO BE ENOUGH
900-700 MB WARMING INTO THE AREA OF DEEPER MOISTURE FOR SOME
FZRA.
SAT NIGHT AND SUN...LOW PRES LIFTING NE TOWARD JAMES BAY SAT NIGHT
WILL DRAG A COLD FRONT THROUGH THE NRN LAKES WITH MUCH COLDER AIR
MOVING IN ON NW WINDS. WITH 850 MB TEMPS FALLING TO NEAR -18C...LES
WILL BE LIKELY FOR NW WIND SNOW BELTS. A LIMITING FACTOR FOR HEAVIER
SNOW WILL BE SUBSTANTIAL 850-700 MB DRYING WITH BACKING AND
INCREASING ACYC LOW LEVEL WINDS FROM LATE SUN INTO SUN NIGHT.
MON-WED...THE GFS/GEFS AND ECMWF WERE IN REASONABLE AGREEMENT WITH
THE PATTERN INTO NEXT WEEK WITH HIGH PRES BUILDING INTO THE REGION
MON INTO MON NIGHT BRINGING DIMINISHING LES. ANOTHER MID LEVEL AND
SFC TROUGH MOVING THROUGH TUE INTO TUE NIGHT COULD BRING SOME LIGHT
SNOW TO THE AREA. THE MODELS HAVE TRENDED TOWARD KEEPING COLDER
ACROSS REGION THAT WOULD KEEP ANY PCPN AS SNOW WITH MAX TEMPS
RECOVERING INTO THE MID 20S TO AROUND 30 BY TUE AND WED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 637 PM EST WED NOV 26 2014
PERIODS OF HEAVIER LK EFFECT SN
DISTURBANCE AND ASSOCIATED SFC TROF WILL SWING ACROSS UPPER MI THIS
AFTN/EVENING. INCREASING LAKE ENHANCED SNOW WILL AFFECT ALL
TERMINALS AS THE TROF PUSHES ACROSS THE AREA...BEGINNING LATEST AT
KSAW. AT KIWD/KCMX...IFR CONDITIONS ARE EXPECTED TO BECOME THE
PREVAILING CONDITION THIS AFTN...THOUGH SOME LIFR WILL OCCUR AS
WELL. WIND FLOW THIS EVENING WILL FAVOR KIWD FOR HEAVIEST
SNOW/LOWEST CONDITIONS...AND LIFR WILL LIKELY PREVAIL THERE THIS
EVENING WHILE KCMX REMAINS IFR. LOWERING INVERSION/DRYING AIR MASS
WILL RESULT IN DIMINISHING LAKE EFFECT SNOW LATER IN THE PERIOD...
ALLOWING IMPOVEMENT TO VFR. AT KSAW...VFR CONDITIONS WILL PREVAIL
THIS AFTN. WITH TROF PASSAGE...EXPECT CONDITIONS TO FALL TO IFR LATE
THIS EVENING ALONG WITH PERIODS OF LIFR. AS WINDS BEGIN TO BACK LATE
TONIGHT AND ESPECIALLY THU MORNING...LAKE EFFECT SNOW WILL SHIFT
MOSTLY E OF KSAW...ALLOWING IMPROVEMENT TO MVFR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 PM EST WED NOV 26 2014
A SFC TROUGH WILL SLIDE SOUTH OVER LAKE SUPERIOR TONIGHT.
BEHIND THE TROUGH...EXPECT NORTHERLY WINDS TO 30 KTS. WINDS WILL
THEN DIMINISH TO UNDER 20 KT W TO E THU/THU NIGHT AS HIGH PRES RIDGE
ARRIVES. WITH ANOTHER COLD FRONT PUSHING ACROSS THE UPPER LAKES SAT
NIGHT...EXPECT INCREASING S/SW WINDS TO 15-25KT FRI INTO SAT AHEAD
OF FRONT. BEHIND THE FRONT...NW WINDS MAY REACH 20-30KT LATE SAT
NIGHT AND SUN AND INCREASE TO GALES BY SUN NIGHT INTO MON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 10 PM THIS EVENING TO 1 PM EST
THURSDAY FOR MIZ006.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THURSDAY FOR MIZ004.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THURSDAY FOR MIZ005.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ THURSDAY FOR
MIZ002-009.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THURSDAY FOR MIZ001-003.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
457 PM EST TUE NOV 25 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 450 PM EST TUE NOV 25 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW AN AMPLIFIED PATTERN OVER
NAMERICA WITH RIDGING ALONG/JUST OFF THE W COAST...A TROF EXTENDING
FROM N OF HUDSON BAY TO TX AND A RIDGE JUST OFF THE EAST COAST.
SHORTWAVE THAT PROVIDED WIDESPREAD SYNOPTIC SNOW AS WELL AS LAKE
ENHANCED SNOW ACROSS THE FCST AREA LAST NIGHT HAS SHIFTED NE INTO
QUEBEC. UPSTREAM...NEXT SHORTWAVE IS DIVING SE INTO THE DAKOTAS. A
LESS DEFINED SHORTWAVE TROF IS FARTHER N OVER NRN PORTIONS OF
MANITOBA/SASKATCHEWAN. DRYING AIR MASS...LOWERING INVERSION AND LOW
LEVEL WINDS BECOMING MORE ANTICYCLONIC WITH SFC HIGH PRES THAT IS
NOW NOSING INTO WRN UPPER MI HAVE RESULTED IN A STEADY DIMINISHING
TREND/SHIFTING OF LINGERING LES THIS AFTN. IN FACT...OVER THE
W...THERE MAY NOT BE MUCH MORE THAN SCT FLURRIES REMAINING. LAKE
EFFECT CLOUD COVER IS ALSO DIMINISHING WITH CLR SKIES NOW BEING
NOTED AROUND KIWD. TO THE W...CLOUDS IN ADVANCE OF AFOREMENTIONED
SHORTWAVES ARE SLOWLY MOVING ACROSS NRN MN.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS TONIGHT...MIN
TEMPS TONIGHT WITH A PROBABLE PERIOD OF CLR/PARTLY CLOUDY SKIES IN
MANY AREAS AND THEN NEXT ROUND OF HEAVIER LES THAT WILL BEGIN TO
ENTER THE PICTURE WED AFTN AS SHORTWAVE TROF SWINGS SE TOWARD THE
UPPER LAKES.
TONIGHT...ARRIVAL OF WEAK SFC HIGH PRES RIDGE COMBINED WITH
STRENGTHENING LAND BREEZES WILL CONTINUE TO SHIFT LINGERING LES
OFFSHORE. OVER THE E...SHIFTING LES SHOULD BE OFFSHORE NO LATER THAN
AROUND MIDNIGHT. OVER THE W...ALTHOUGH THERE IS PROBABLY NOT MUCH
MORE THAN FLURRIES CURRENTLY REMAINING...NOCTURNAL COOLING AND LAND
BREEZE DEVELOPMENT RESULTING IN INCREASING CONVERGENCE SHOULD FAVOR
SOME REDEVELOPMENT OF LES DURING THE NIGHT. AMONG THE HIGH RES
MODELS...THERE IS DISAGREEMENT IN WHETHER SE MOVING SFC TROF WILL
SINK FAR ENOUGH S TO KEEP LES OVER THE KEWEENAW. AT THIS POINT...
BELIEVE SW FLOW ENHANCED BY LAND BREEZE WILL PUSH LES OFFSHORE...BUT
THERE IS ENOUGH UNCERTAINTY TO MAINTAIN SOME SCT -SHSN WORDING OVER
THE NRN PORTION OF THE KEWEENAW OVERNIGHT. AS FOR TEMPS...BASED ON
SATELLITE IMAGERY...IT LOOKS LIKE THERE WILL BE A DECENT PERIOD OF
CLEAR TO PARTLY CLOUDY SKIES TONIGHT OVER MUCH OF THE AREA. WITH
LIGHT WINDS AND PRECIPITABLE WATER 40-55PCT OF NORMAL...FAVORED THE
LOW END OF GUIDANCE. TEMPS SHOULD PLUMMET RAPIDLY THIS EVENING WHERE
SKIES ARE CLEAR...AND EXPECT TRADITIONAL COLD SPOTS TO FALL TO
AROUND -5F. HOWEVER...GIVEN THE SLOW ADVANCE OF UPSTREAM CLOUDS...
CLOUDS MAY BE SLOWER TO ARRIVE THAN CURRENTLY FCST. COMBINED WITH
FRESH SNOW COVER...COULD EASILY SEE TEMPS FALL TO -10F OR LWR IN THE
USUAL COLD SPOTS.
SHORTWAVE CURRENTLY MOVING INTO THE DAKOTAS WILL CONTINUE TO DROP SE
TOWARD THE TENNESSEE VALLEY TONIGHT/WED AND WILL HAVE NO INFLUENCE
HERE AS IT PASSES WELL S OF UPPER MI. OF CONCERN IS THE FOLLOWING
SHORTWAVE TROF WHICH WILL SWING SE AND EXTEND FROM JAMES BAY TO MN
BY 00Z THU. AS HEIGHT FALLS/MODEST DEEP LAYER FORCING PER QVECTORS
OVERSPREAD THE RELATIVELY WARM WATERS OF LAKE SUPERIOR...SFC TROF
MOVING OVER THE LAKE WILL SHARPEN UP...RESULTING IN INCREASING
CONVERGENCE AND INTENSIFYING LAKE ENHANCED SNOW ALONG/NEAR TROF.
EXPECT THIS TROF TO REACH THE KEWEENAW DURING THE MORNING AND THE W
IN THE AFTN. TROF PROBABLY WON`T REACH NCNTRL UPPER MI UNTIL
EVENING. NE ORIENTATION OF THE WINDS ACROSS THE KEWEENAW AFTER
TROF PASSAGE WON`T BE ESPECIALLY FAVORABLE FOR PERSISTENT HEAVIER
LAKE ENHANCED SNOW AFTER THE MAIN MDT/HVY SNOW BAND ALONG TROF
SHIFTS S. FARTHER S...SHARPER LOW-LEVEL CONVERGENCE AND BETTER
UPSLOPING IS EXPECTED INTO ONTONAGON/GOGEBIC COUNTIES...AND THIS IS
INDICATED IN MODEL GUIDANCE IN LOW-LEVEL OMEGA FIELDS. WIND FLOW
SUGGESTS LAKE NIPIGON PRECONDITONING WILL ALSO COME INTO PLAY OVER
THE FAR W. WITH THESE FAVORABLE CONDITIONS CONTINUING INTO THE WED
NIGHT...WILL HOIST A LAKE EFFECT SNOW ADVISORY FOR ONTONAGON/GOGEBIC
STARTING AT 20Z WED. IN GENERAL...A QUICK COUPLE OF INCHES OF SNOW
WILL PROBABLY OCCUR AS THE TROF MOVES ONSHORE OVER THE W.
ELSEWHERE...SOME -SN SHOULD GRADUALLY OVERSPREAD THE REST OF WRN
UPPER MI IN THE AFTN. TO THE E...IT APEARS WINDS WILL BACK
SUFFICIENTLY TO BRING SOME LES OFF LAKE MICHIGAN INTO THE FAR ERN
FCST AREA IN THE AFTN. WINDS ARE LIGHT/CONVERGENCE WEAK...SO NOT
EXPECTING MUCH WITH THE LES OFF LAKE MI WED (LESS THAN 1 INCH).
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 457 PM EST TUE NOV 25 2014
MAIN FCST CONCERNS IN THE LONG TERM WL FOCUS ON LES POTENTIAL FOR
WED NIGHT INTO THANKSGIVING AND NEED FOR HEADLINES AT SENSITIVE
TRAVEL TIME. ANOTHER ROUND OF SN WL BE POSSIBLE ON FRI/FRI NIGHT
WITH DVLPG ISENTROPIC ASCENT UNDER AN UPPER AIR PATTERN THAT WL
SHIFT TO A PROGRESSIVE...ZONAL FLOW BY THE WEEKEND. WELL BLO NORMAL
TEMPS WITH SOME RECORD LO MAX TEMPS ON THANKSGIVING WL GIVE WAY TO
MUCH WARMER WX ON SAT. ALTHOUGH SOME COLDER AIR WL RETURN FOR SUN
INTO MON...A WARMER SW FLOW ON THE WRN FLANK OF HI PRES SHIFTING TO
THE E WILL DVLP ON TUE UNDER THIS PROGRESSIVE PATTERN.
WED NGT...STEADY N BACKING NNW WIND IN THE WAKE OF PASSING NRN
STREAM SHRTWV IS FCST TO ADVECT COLDER AIR INTO THE UPR LKS WITH H85
TEMPS FALLING AS LO AS -18C OVER THE KEWEENAW BY 12Z THU...A FVRBL
SETUP FOR LES. EXPECT A PERIOD OF SOME HEAVIER LK ENHANCED SN IN THE
FAVORED SN BELTS WHEN AREA OF DPVA/DEEP LYR QVECTOR CNVGC/UVV/DEEP
MSTR ASSOCIATED WITH THE PASSING DISTURBANCE COINCIDES WITH FVRBL
UPSLOPE...WEAKLY CYC N FLOW. AREAS OVER ONTONAGON/GOGEBIC IN THE
EVNG AND MARQUETTE/ALGER COUNTIES IN THE LATER EVNG/EARLY OVERNGT
APPEAR TO BE MOST FAVORED TO SEE HEAVIER SN. ENHANCEMENT FACTOR FOR
HEAVIER SN TOTALS INCLUDE FAIRLY DEEP DGZ UP TO 4K FT. ALTHOUGH THE
SHARPEST UVV IS FCST TO BE JUST BLO THE DGZ MUCH OF THE TIME...THERE
WL BE SOME UVV IN THIS ZONE THAT SHOULD ALLOW SN/WATER RATIOS UP TO
20-25:1. ONE NEGATIVE APPEARS TO BE THE ABSENCE OF SHARP CYC FLOW/
PERSISTENT LLVL CNVGC. ALTHOUGH THE LK ENHANCEMENT WL NOT BE A
PLAYER WELL INLAND FM LK SUP...DYNAMIC FORCING SHOULD ALLOW FOR SOME
LIGHT SN EVEN OVER THE SCENTRAL. BUT ABSENCE OF HIER ABSOLUTE MSTR..
.WITH PWAT NO MORE THAN ABOUT 0.3 INCH AND H7 SPECIFIC HUMIDITY
ABOUT 1G/KG...WL LIMIT SN TOTALS TO NO MORE THAN AN INCH OR SO AWAY
FM LK ENHANCEMENT/UPSLOPE WINDS. LATER AT NGT...EXPECT THE SN TO
DIMINISH NW-SE WITH THE ARRIVAL OF DNVA/DEEP LYR QVECTOR DVGC/
SUBSIDENCE/MID LVL DRYING IN THE WAKE OF THE PASSING SHRTWV THAT IS
FCST TO STRENGTHEN INVRN AS LO AS H875-9 AS SHOWN ON NAM FCST SDNGS.
ALTHOUGH IT IS NOT COMMON PRACTICE TO ISSUE AN ADVY FOR PRIMARLIY A
3RD PERIOD EVENT...SENSITIVE TRAVEL TIME JUST BEFORE THANKSGIVING
HOLIDAY AS WELL AS FAVORABLE UPSLOPE FLOW/FAIRLY EFFICIENT SN GROWTH
PARAMETERS WARRANTS EARLY ISSUANCE OF AN LES ADVY IN THE FAVORED
AREAS OVER THE W/NCENTRAL DESPITE THE RATHER FLUFFY NATURE OF THE SN
THAT IS EXPECTED TO FALL. THE LES ADVY WL INCLUDE GOGEBIC/
ONTONAGON/MARQUETTE AND ALGER COUNTIES. AS MUCH AS 7 TO 8 INCHES OF
SN WL FALL IN THESE AREAS THRU THE ADVY PERIOD. N WINDS GUSTING UP
TO 25-30 MPH WL CAUSE SOME BLSN NEAR LK SUP WED NIGHT INTO THU MRNG.
THANKSGIVING/THU NGT...THE LLVL FLOW IS PROGGED TO BACK STEADILY AND
TURN MORE ACYC ON THANKSGIVING WITH SFC HI PRES MOVING TOWARD SW WI
LATE IN THE DAY UNDER HGT RISES/DNVA IN ADVANCE OF APRCHG SHRTWV
RDG. THE RESULT WL BE SHIFTING/DIMINISHING LES BANDS...ESPECIALLY
OVER THE W HALF. THE SN SHOWERS SHOULD END COMPLETELY AT IWD LATE IN
THE AFTN. THE LES WL BE MORE PERSISTENT IN THE FAVORED SN BELTS E OF
MARQUETTE WITH H85 THERMAL TROF/TEMPS ARND -18C REACHING THAT AREA
LATE IN THE DAY...BUT INCRSG ACYC FLOW AND ABSENCE OF SGNFT LLVL
CNVGC/LOWERING INVRN BASE TO H875-9 SHOWN ON THE FCST SDNGS UNDER
THE NEGATIVE DYNAMICS WL LIMIT SN TOTALS. THANKSGIVING WL BE QUITE
CHILLY WITH H85 THERMAL TROF PASSING OVHD AND COULD FEATURE SOME
RECORD LO MAX TEMPS. EXPECT THE LOWEST TEMPS OVER THE W HALF WHERE
BACKING FLOW WL LIMIT LK SUP MODERATION. AS THE SFC RDG AXIS SHIFTS
TO THE E AND THE FLOW BACKS TO THE W-SW...LINGERING LES WL SHIFT OUT
INTO LK SUP ON THU NGT. TEMPS COULD FALL QUICKLY IN THE EVNG TOWARD
THE LO END OF GUIDANCE BEFORE MORE HI CLDS OVERSPREAD THE AREA W-E
ASSOCIATED WITH DVLPG ISENTROPIC ASCENT IN THE SW FLOW ON THE NW
FLANK OF PRES SHIFTING INTO THE OH RIVER VALLEY AND IN ADVANCE OF
SHRTWV STREAKING EWD TOWARD MN. SOME OF THE FASTER MODELS SHOW SN
ASSOCIATED WITH THIS WAA/SHRTWV REACHING THE FAR W BY 12Z FRI...SO
WL MAINTAIN SOME LO CHC POPS IN THIS AREA LATE THU NGT.
FRI/FRI NGT...AS THE UPR TROF IN ERN NAMERICA SHIFTS TO THE E...THE
FLOW OVER THE CONUS/SRN CANADA WL BECOME MORE ZONAL. DVLPG LLVL SW
FLOW/ISENTROPIC ASCENT OVER THE GREAT LKS ON THE NW FLANK OF SFC HI
PRES SHIFTING INTO THE SRN MID ATLANTIC STATES AND IN ADVANCE OF
SHRTWV TRACKING EWD THRU MN IS PROGGED BY MOST OF THE MEDIUM RANGE
GUIDANCE TO BRING ABOUT SOME INCRSG MID LVL MSTR/PCPN ON FRI TO THE
NE OF AN H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO MN AND WI.
ALTHOUGH INITIAL SHOT OF SHARPER ISENTROPIC ASCENT BEST SHOWN ON THE
280-290K SFCS/H85-7 FGEN AXIS/DEEP LYR QVECTOR CNVGC IS FCST TO
IMPACT NRN WI ON FRI MRNG...THIS WAA/FORCING MAY SHIFT FARTHER N
INTO UPR MI DURING THE DAY. H7 SPECIFIC HUMIDITY IS FCST AS HI AS 3
G/KG...SO NOT OUT OF THE QUESTION THERE COULD BE SOME MODERATE SN
AMOUNTS APRCHG ADVY CRITERIA OVER THE SRN CWA. AS THE H925 WINDS
BECOME MORE S IN THE PRESENCE OF H85 TEMPS IN THE -8 TO -10C
RANGE...LES OFF LK MI WL IMPACT THE ERN CWA. WL MAINTAIN THE HIER
POPS/QPF IN THIS AREA. ON FRI NGT...MORE NOTABLE MODEL DIFFERENCES
ARE SHOWING UP WITH THE 12Z GFS SHOWING A MORE WNW VS W FLOW ALOFT
AND A STRONGER SHRTWV/SFC LO TRACKING FASTER E ACROSS LK SUP ON FRI
NGT...WITH CYC NW FLOW OF COLDER AIR DVLPG OVER THE CWA LATE FRI
NGT. THIS SOLUTION IS VERY MUCH AN OUTLIER EVEN AMONG THE MOST
RECENT GFS ENSEMBLE GUIDANCE... SO TENDED TO FOLLOW THE MORE
CONSISTENT 12Z CNDN/00Z AND 12Z ECMWF MODELS. THIS GUIDANCE SHOWS A
SLOWER SFC LO AND MORE AGGRESSIVE PUSH TO THE NE OF H85 WARM
FNT...WITH H85 TEMPS RISING ABOVE 0C OVER THE SCENTRAL CWA BY 12Z
SAT ACCOMPANYING DRY SLOTTING/LOWERING POPS OVER THE SRN TIER. WITH
ECWMF SDNGS SHOWING LINGERING LLVL MSTR BLO THE WARMING/DRYING WARM
NOSE ARND H85...ADDED A MENTION OF SOME FREEZING DZ OVER THE SW CWA.
SAT/SAT NGT...SHRTWV EMBEDDED IN ZONAL FLOW OVER SRN CANADA WL
STREAM E...WITH ACCOMPANYING SFC LO STREAKING ENEWD THRU ONTARIO AND
THEN DRAGGING A COLD FNT ACRS THE CWA SAT NGT. AHEAD OF THIS FNT...
MORE CONSISTENT...FAVORED 12Z ECMWF/CNDN MODELS SHOW WARM SURGE INTO
THE UPR LKS WITH H85 TEMPS RISING AS HI AS 8-10C OVER THE SRN TIER
ON SAT UNDER SOME MID LVL DRYING. TENDED TO CUT POPS OVER THE SRN
TIER...WHERE THE ECMWF AND CNDN MODELS SHOW MORE AGGRESSIVE MID LVL
DRYING FARTHER FM THE LO TRACK. CONTINUED TO MENTION SOME RA OR
FREEZING DZ IN THESE AREAS AS WELL. FARTHER TO THE N CLOSER TO THE
LO TRACK AND SOMEWHAT HIER CHC POPS...INCLUDED MENTION OF FREEZING
RA AND RA IN ADDITION TO SN IN CASE THE AIRMASS IS A BIT COLDER. IF
SFC TEMPS END UP HIER THAN CURRENTLY FCST...LATER SHIFTS MAY BE ABLE
TO CUT BACK ON THE FREEZING DZ/RA AND GO WITH PLAIN RA. RIGHT NOW...
LOOKS LIKE ANY ICE ACCUMULATION WL BE MINOR.
EXTENDED...MUCH COLDER AIR...WITH H85 TEMPS FCST AS LO AS -18C BY
00Z MON...AND SOME LK EFFECT SN WL FOLLOW ON SUN UNDER NW FLOW BTWN
DEPARTING COLD FNT AND CNDN HI PRES BLDG E THRU THE NRN PLAINS. BUT
SINCE THE UPR FLOW WL REMAIN FAIRLY PROGRESSIVE...THE SFC HI PRES WL
SHIFT THRU THE GREAT LKS ON MON AND INTO NEW ENGLAND TUE AS UPR RDG
BLDS INTO THE UPR LKS ON TUE. THE RESULT SHOULD BE DIMINISHING LES
ON MON WITH DRY WX LINGERING INTO TUE. WARMER SW FLOW ON THE WRN
FLANK OF DEPARTING SFC HI PRES MAY DRAW ENUF MSTR TO THE N ON TUE TO
BRING A RETURN OF SOME SN OR A RA/SN MIX.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1248 PM EST TUE NOV 25 2014
DRIER AIR AND BACKING WINDS TO THE SW WITH APPROACHING WEAK SFC HIGH
PRES RIDGE WILL RESULT IN LAKE EFFECT -SHSN ENDING AND MVFR
CONDITIONS IMPROVING TO VFR AT KIWD DURING THE MID AFTN AND AT KSAW
LATE THIS AFTN. MAY YET SEE SOME BRIEF IFR CONDITIONS AT KSAW BASED
ON RADAR IMAGERY SHOWING HEAVIER SNOW SHOWERS IN NCNTRL UPPER MI.
VFR CONDITIONS WILL CONTINUE AT KIWD/KSAW TONIGHT. NEXT APPROACHING
DISTURBANCE MAY BRING SOME -SN/MVFR CONDITIONS TO KIWD LATE WED
MORNING. AT KCMX...WINDS WILL PROBABLY RETAIN ENOUGH OVERWATER
COMPONENT TO MAINTAIN MVFR CONDITIONS THRU THE NIGHT EVEN THOUGH
-SHSN SHOULD END. BEFORE THE -SHSN END...THERE MAY BE A PERIOD OF
SOMEWHAT HEAVIER SNOW SHOWERS AT KCMX THIS EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 PM EST TUE NOV 25 2014
PRES GRADIENT RAPIDLY WEAKENS TONIGHT WITH A WEAK SFC TROF DROPPING
SE OVER LAKE SUPERIOR. THIS WILL RESULT IN WINDS DIMINISHING TO UNDER
20KT ACROSS THE LAKE. STRONG HIGH PRES WILL THEN BUILD SE INTO THE
CANADIAN PRAIRIES WED AND INTO THE NRN PLAINS WED NIGHT. THIS WILL
PUSH THE TROF SE AND TIGHTEN THE PRES GRADIENT. AS A RESULT... WITH
THE TROF PASSAGE...EXPECT NORTHERLY WINDS TO RAMP UP TO 20-30KT FROM
NW TO SE WED/WED NIGHT. NOT OUT OF THE QUESTION THAT THERE COULD BE
SOME GALE FORCE GUSTS OVER THE CNTRL PORTION OF LAKE SUPERIOR. WINDS
WILL THEN DIMINISH TO UNDER 20KT W TO E THU/THU NIGHT AS HIGH PRES
RIDGE ARRIVES. WITH ANOTHER COLD FRONT PUSHING ACROSS THE UPPER LAKES
SAT...EXPECT INCREASING WINDS TO 15-25KT FRI/FRI NIGHT AHEAD OF
FRONT. BEHIND FRONT...NW WINDS MAY REACH 20-30KT LATE SAT/SUN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 10 PM WEDNESDAY TO 1 PM EST
THURSDAY FOR MIZ006.
LAKE EFFECT SNOW ADVISORY FROM 7 PM WEDNESDAY TO 10 AM EST
THURSDAY FOR MIZ005.
LAKE EFFECT SNOW ADVISORY FROM 3 PM EST /2 PM CST/ WEDNESDAY TO
10 AM EST /9 AM CST/ THURSDAY FOR MIZ002-009.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KC
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
452 PM EST TUE NOV 25 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 450 PM EST TUE NOV 25 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW AN AMPLIFIED PATTERN OVER
NAMERICA WITH RIDGING ALONG/JUST OFF THE W COAST...A TROF EXTENDING
FROM N OF HUDSON BAY TO TX AND A RIDGE JUST OFF THE EAST COAST.
SHORTWAVE THAT PROVIDED WIDESPREAD SYNOPTIC SNOW AS WELL AS LAKE
ENHANCED SNOW ACROSS THE FCST AREA LAST NIGHT HAS SHIFTED NE INTO
QUEBEC. UPSTREAM...NEXT SHORTWAVE IS DIVING SE INTO THE DAKOTAS. A
LESS DEFINED SHORTWAVE TROF IS FARTHER N OVER NRN PORTIONS OF
MANITOBA/SASKATCHEWAN. DRYING AIR MASS...LOWERING INVERSION AND LOW
LEVEL WINDS BECOMING MORE ANTICYCLONIC WITH SFC HIGH PRES THAT IS
NOW NOSING INTO WRN UPPER MI HAVE RESULTED IN A STEADY DIMINISHING
TREND/SHIFTING OF LINGERING LES THIS AFTN. IN FACT...OVER THE
W...THERE MAY NOT BE MUCH MORE THAN SCT FLURRIES REMAINING. LAKE
EFFECT CLOUD COVER IS ALSO DIMINISHING WITH CLR SKIES NOW BEING
NOTED AROUND KIWD. TO THE W...CLOUDS IN ADVANCE OF AFOREMENTIONED
SHORTWAVES ARE SLOWLY MOVING ACROSS NRN MN.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS TONIGHT...MIN
TEMPS TONIGHT WITH A PROBABLE PERIOD OF CLR/PARTLY CLOUDY SKIES IN
MANY AREAS AND THEN NEXT ROUND OF HEAVIER LES THAT WILL BEGIN TO
ENTER THE PICTURE WED AFTN AS SHORTWAVE TROF SWINGS SE TOWARD THE
UPPER LAKES.
TONIGHT...ARRIVAL OF WEAK SFC HIGH PRES RIDGE COMBINED WITH
STRENGTHENING LAND BREEZES WILL CONTINUE TO SHIFT LINGERING LES
OFFSHORE. OVER THE E...SHIFTING LES SHOULD BE OFFSHORE NO LATER THAN
AROUND MIDNIGHT. OVER THE W...ALTHOUGH THERE IS PROBABLY NOT MUCH
MORE THAN FLURRIES CURRENTLY REMAINING...NOCTURNAL COOLING AND LAND
BREEZE DEVELOPMENT RESULTING IN INCREASING CONVERGENCE SHOULD FAVOR
SOME REDEVELOPMENT OF LES DURING THE NIGHT. AMONG THE HIGH RES
MODELS...THERE IS DISAGREEMENT IN WHETHER SE MOVING SFC TROF WILL
SINK FAR ENOUGH S TO KEEP LES OVER THE KEWEENAW. AT THIS POINT...
BELIEVE SW FLOW ENHANCED BY LAND BREEZE WILL PUSH LES OFFSHORE...BUT
THERE IS ENOUGH UNCERTAINTY TO MAINTAIN SOME SCT -SHSN WORDING OVER
THE NRN PORTION OF THE KEWEENAW OVERNIGHT. AS FOR TEMPS...BASED ON
SATELLITE IMAGERY...IT LOOKS LIKE THERE WILL BE A DECENT PERIOD OF
CLEAR TO PARTLY CLOUDY SKIES TONIGHT OVER MUCH OF THE AREA. WITH
LIGHT WINDS AND PRECIPITABLE WATER 40-55PCT OF NORMAL...FAVORED THE
LOW END OF GUIDANCE. TEMPS SHOULD PLUMMET RAPIDLY THIS EVENING WHERE
SKIES ARE CLEAR...AND EXPECT TRADITIONAL COLD SPOTS TO FALL TO
AROUND -5F. HOWEVER...GIVEN THE SLOW ADVANCE OF UPSTREAM CLOUDS...
CLOUDS MAY BE SLOWER TO ARRIVE THAN CURRENTLY FCST. COMBINED WITH
FRESH SNOW COVER...COULD EASILY SEE TEMPS FALL TO -10F OR LWR IN THE
USUAL COLD SPOTS.
SHORTWAVE CURRENTLY MOVING INTO THE DAKOTAS WILL CONTINUE TO DROP SE
TOWARD THE TENNESSEE VALLEY TONIGHT/WED AND WILL HAVE NO INFLUENCE
HERE AS IT PASSES WELL S OF UPPER MI. OF CONCERN IS THE FOLLOWING
SHORTWAVE TROF WHICH WILL SWING SE AND EXTEND FROM JAMES BAY TO MN
BY 00Z THU. AS HEIGHT FALLS/MODEST DEEP LAYER FORCING PER QVECTORS
OVERSPREAD THE RELATIVELY WARM WATERS OF LAKE SUPERIOR...SFC TROF
MOVING OVER THE LAKE WILL SHARPEN UP...RESULTING IN INCREASING
CONVERGENCE AND INTENSIFYING LAKE ENHANCED SNOW ALONG/NEAR TROF.
EXPECT THIS TROF TO REACH THE KEWEENAW DURING THE MORNING AND THE W
IN THE AFTN. TROF PROBABLY WON`T REACH NCNTRL UPPER MI UNTIL
EVENING. NE ORIENTATION OF THE WINDS ACROSS THE KEWEENAW AFTER
TROF PASSAGE WON`T BE ESPECIALLY FAVORABLE FOR PERSISTENT HEAVIER
LAKE ENHANCED SNOW AFTER THE MAIN MDT/HVY SNOW BAND ALONG TROF
SHIFTS S. FARTHER S...SHARPER LOW-LEVEL CONVERGENCE AND BETTER
UPSLOPING IS EXPECTED INTO ONTONAGON/GOGEBIC COUNTIES...AND THIS IS
INDICATED IN MODEL GUIDANCE IN LOW-LEVEL OMEGA FIELDS. WIND FLOW
SUGGESTS LAKE NIPIGON PRECONDITONING WILL ALSO COME INTO PLAY OVER
THE FAR W. WITH THESE FAVORABLE CONDITIONS CONTINUING INTO THE WED
NIGHT...WILL HOIST A LAKE EFFECT SNOW ADVISORY FOR ONTONAGON/GOGEBIC
STARTING AT 20Z WED. IN GENERAL...A QUICK COUPLE OF INCHES OF SNOW
WILL PROBABLY OCCUR AS THE TROF MOVES ONSHORE OVER THE W.
ELSEWHERE...SOME -SN SHOULD GRADUALLY OVERSPREAD THE REST OF WRN
UPPER MI IN THE AFTN. TO THE E...IT APEARS WINDS WILL BACK
SUFFICIENTLY TO BRING SOME LES OFF LAKE MICHIGAN INTO THE FAR ERN
FCST AREA IN THE AFTN. WINDS ARE LIGHT/CONVERGENCE WEAK...SO NOT
EXPECTING MUCH WITH THE LES OFF LAKE MI WED (LESS THAN 1 INCH).
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 416 AM EST TUE NOV 25 2014
...ACTIVE WITH FREQUENT CHANCES OF LAKE EFFECT OFF BOTH SUPERIOR AND
MICHIGAN...
BROAD TROUGHING ALOFT OVER EASTERN TWO THIRDS OF NORTH AMERICA TO
START THE LONG TERM PERIOD ON WEDNESDAY. PRIMARY SHORTWAVE AND SFC
LOW WITH SWATH OF SNOW OVER THE MID CONUS SHOULD STAY WELL TO THE
SOUTH OVER THE MIDDLE MISSISSIPPI RIVER VALLEY. SHORTWAVE IN THE
NORTHERN STREAM SLIDES FROM SOUTHERN MANITOBA TOWARD UPPER GREAT
LAKES REGION ON WEDNESDAY AFTN. EVEN THOUGH SFC LOW WILL BE WELL TO
SOUTH...TROUGHING SFC-925MB DEVELOPS VCNTY OF LK SUPERIOR AND UPR
MICHIGAN IN RESPONSE THE NORTHERN STREAM SHORTWAVE AND SHARP TEMP
GRADIENT FM NORTHERN ONTARIO TO THE UPPER GREAT LAKES. SE/S WINDS
AHEAD OF THE SFC TROUGH AND MOISTURE TO H85 WITH H85 TEMPS OF -10C
SHOULD SUPPORT SOME LAKE EFFECT OFF NORTHERN LK MICHIGAN INTO THE
EASTERN CWA. MARGINAL INSTABILITY AND LACK OF ENHANCEMENT FACTORS
SHOULD LIMIT LES INTENSITY OVER EAST CWA MOST OF WEDNESDAY. COULD
SEE INCREASE ON WEDNESDAY EVENING WITH LITTLE CHANGE IN LOW-LEVEL
WINDS AND TEMPS BUT INCREASING MOISTURE/LIFT AS THE SHORTWAVE AND
DEEP LAYER Q-VECTOR CONVERGENCE MOVES THROUGH. LATER ON WEDNESDAY
NIGHT...WINDS BECOME W-WNW BLO H85 WHICH WILL DIMINISH THE LES FOR
THE EASTERN CWA.
MEANWHILE...EXPECT LES ON THE KEWEENAW IN WESTERLY LOW-LEVEL FLOW
ON WEDNESDAY MORNING TO SHIFT TO THE AREAS OF WESTERN UPR MICHIGAN
AND EVENTUALLY NORTH CENTRAL UPR MICHIGAN ON WEDNESDAY AFTN INTO
WEDNESDAY EVENING AS WINDS TURN NORTHERLY IN WAKE OF THE SFC TROUGH
PASSAGE. NNE WINDS H95-H85 WITH NORTH WINDS AT SFC AND TEMPS AT H85
OF -15C LEADING TO DELTA T/S NEARING 20C SUPPLEMENTED WITH LARGER
SCALE FORCING FM THE SHORTWAVE COULD RESULT IN HEAVY LES FOR FAR
WEST UPR MICHIGAN...VCNTY OF GOGEBIC COUNTY...LATE WEDNESDAY AFTN
THROUGH MUCH OF WEDNESDAY NIGHT. SIMILAR POTENTIAL FOR HIGHER
TERRAIN OF BARAGA AND MARQUETTE COUNTY WEDNESDAY NIGHT THROUGH
AROUND DAYBREAK ON THANKSGIVING MORNING. SHORTWAVE LIKELY WILL
PRODUCE WIDESPREAD LGT SNOW FOR MOST OF THE CWA AWAY FM THE LAKE
EFFECT AREAS. MOISTURE LACKING WITH H7 MIXING RATIOS AROUND 1G/KG.
THROUGH AND NAM/GFS SOUNDINGS POINT TO MAYBE 6 HOURS OF SNOW AT
IMT/ESC...SO PROBABLY LOOKING AT UP TO AN INCH OF FLUFFY SNOW FOR
AREAS AWAY FM LK SUPERIOR. WINDS UP TO 30 KTS WITHIN THE MIXED LAYER
BUT DOES NOT APPEAR TO BE ESPECIALLY WINDY...SO ALTHOUGH THERE WILL
BE SOME BLSN DOES NOT SEEM THAT WILL BE WIDESPREAD.
INTO THANKSGIVING...WILL BE IMPROVING TREND TO WEATHER AWAY FM LK
SUPERIOR...BUT EXPECT LAKE EFFECT TO PERSIST THROUGH MOST OF THE DAY
ALONG LK SUPERIOR. SOUNDINGS SHOW A CHILLY AIRMASS WITH GRADUALLY
LOWERING INVERSIONS BLO 5KFT BY 00Z FRIDAY. MAX TEMPS ONLY IN THE
LOWER TEENS WEST HALF AND AROUND 20 DEGREES EAST HALF...WELL BLO
NORMAL FOR LATE NOVEMBER AND LIKELY NEAR A RECORD LOW MAX TEMP FOR
THIS DAY. TEMPS AT TOP OF INVERSION HOVER AROUND -18C THROUGH THE
DAY WHICH WILL BE PLENTY GOOD ENOUGH FOR LAKE EFFECT WITH LK
SUPERIOR WATER TEMPS NOW AROUND 3-4C. SNOW SHOULD BE FAIRLY FLUFFY
AS MAJORITY OF CLOUD BEARING LAYER WILL BE WITHIN THE DGZ. SLR/S
COULD BE PUSHING 30:1...SO THAT FLUFF COULD ADD UP QUICKLY.
CONFIDENCE INCREASING THAT WILL NEED ANOTHER ROUND OF LAKE EFFECT
SNOW HEADLINES FOR AREAS ALONG LK SUPERIOR WEDNESDAY AFTN INTO EARLY
THURSDAY. ISOLD WARNING AMOUNTS MAY OCCUR FOR HIGHER TERRAIN AREAS
FAVORED BY NNE WINDS... BUT MOSTLY EXPECT ADVY TYPE SNOWS. NO
HEADLINES THOUGH NOW WITH CURRENT LAKE EFFECT EVENT STILL RUNNING
ITS COURSE. WILL HIGHLIGHT IN THE HWO AND WITHIN THE EWHO GRAPHICS.
ONCE THE SHORTWAVE ON THANKSGIVING CLEARS THE AREA...UPPER LEVEL
FLOW FLATTENS OUT SOME...BUT STAYS WNW COMPARED TO THE WESTERLY FLOW
MODELS INDICATED 24 HR AGO. RESULT IS TIGHT BAROCLINIC ZONE AT
925-850MB STAYS TO THE WEST AND SOUTH OF UPR MICHIGAN. THUS WHEN THE
NEXT SERIES OF SHORTWAVES AND UPPER LEVEL JET PUSH ACROSS THE
NORTHERN PLAINS...MODELS NOW SHOW BAND OF MODERATE SNOW WILL STAY
MOSTLY ALONG THE BAROCLINIC ZONE TO THE SOUTH OF UPR MICHIGAN. H7
MIXING RATIOS 3-4G/KG SUGGEST WHEREVERE THAT BAND OF SNOW DEVELOPS
IT COULD BE AT LEAST MODERATE. MAIN ISSUE OVER UPR MICHIGAN FM THAT
SYSTEM MAY BE LAKE ENHANCED SNOW OVER EASTERN CWA OFF LK MICHIGAN
DUE TO FORCING FM THE SYSTEM GLANCING THE AREA...SSW WINDS
SFC-H85...AND H85 TEMPS -10C OR LOWER. MOST IDEAL LAKE ENHANCEMENT
PERIOD FRIDAY AFTN THROUGH FRIDAY EVENING OVER SOUTHERN SCHOOLCRAFT
INTO LUCE COUNTIES. INCREASED QPF/SNOW AMOUNTS MARKEDLY. LIKELY A
HEADLINE WILL BE NEEDED FOR THOSE AREAS AT LEAST FRIDAY/FRIDAY NIGHT.
ANOTHER SHORTWAVES QUICKLY FOLLOWS FOR SATURDAY. AT THIS POINT
BETTER FORCING AND THUS QPF STAYS ALONG AND NORTH OF LK SUPERIOR.
SOME INDICATION OF AT LEAST LGT PRECIP OVER THE CWA THOUGH. WARM
LAYER H8-H9 BECOMES MORE OF AN ISSUE. ECMWF WARMER THAN GFS AND
WOULD SUGGEST MOSTLY RAIN AS PTYPE OVER MUCH OF CWA BY SATURDAY
AFTN. GFS HAS MAINLY SNOW WITH A LITTLE RAIN WORKING IN OVER SCNTRL.
COULD BE FZRA IF WARMING AT SFC IS DELAYED. BLENDED TWO SOLUTIONS
FOR NOW AND CAME UP WITH HIGHER POPS NORTH AND MOSTLY SNOW IN
MORNING TRENDING TOWARD MORE RAIN/FZRA IN AFTN. FZRA MAY BE NOT AS
LONG LASTING THOUGH...ESPECIALLY IF THE WARMER ECMWF IDEA IS CORRECT
AS SFC WARMING WOULD BE MORE THAN IS SHOWN IN THIS FORECAST. EITHER
WAY...IF THE PRECIP OCCURS...COULD BE KIND OF A MESSY DEAL.
BECOMES COLDER AGAIN /H85 TEMPS -16C TO -20C/ BEHIND THAT SYSTEM TO
CLOSE THE WEEKEND. MORE LES EXPECTED FOR NW FLOW AREAS ALONG LK
SUPERIOR INTO MONDAY. CYCLONIC FLOW LACKING THOUGH AS BROAD HIGH
PRESSURE RIDGE OVER 1035MB EXPANDS FM THE NORTHERN PLAINS TO THE
GREAT LAKES. ANTICYCLONIC FLOW SHOULD LIMIT THE LES COVERAGE AND
INTENSITY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1248 PM EST TUE NOV 25 2014
DRIER AIR AND BACKING WINDS TO THE SW WITH APPROACHING WEAK SFC HIGH
PRES RIDGE WILL RESULT IN LAKE EFFECT -SHSN ENDING AND MVFR
CONDITIONS IMPROVING TO VFR AT KIWD DURING THE MID AFTN AND AT KSAW
LATE THIS AFTN. MAY YET SEE SOME BRIEF IFR CONDITIONS AT KSAW BASED
ON RADAR IMAGERY SHOWING HEAVIER SNOW SHOWERS IN NCNTRL UPPER MI.
VFR CONDITIONS WILL CONTINUE AT KIWD/KSAW TONIGHT. NEXT APPROACHING
DISTURBANCE MAY BRING SOME -SN/MVFR CONDITIONS TO KIWD LATE WED
MORNING. AT KCMX...WINDS WILL PROBABLY RETAIN ENOUGH OVERWATER
COMPONENT TO MAINTAIN MVFR CONDITIONS THRU THE NIGHT EVEN THOUGH
-SHSN SHOULD END. BEFORE THE -SHSN END...THERE MAY BE A PERIOD OF
SOMEWHAT HEAVIER SNOW SHOWERS AT KCMX THIS EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 450 PM EST TUE NOV 25 2014
PRES GRADIENT RAPIDLY WEAKENS TONIGHT WITH A WEAK SFC TROF DROPPING
SE OVER LAKE SUPERIOR. THIS WILL RESULT IN WINDS DIMINISHING TO UNDER
20KT ACROSS THE LAKE. STRONG HIGH PRES WILL THEN BUILD SE INTO THE
CANADIAN PRAIRIES WED AND INTO THE NRN PLAINS WED NIGHT. THIS WILL
PUSH THE TROF SE AND TIGHTEN THE PRES GRADIENT. AS A RESULT... WITH
THE TROF PASSAGE...EXPECT NORTHERLY WINDS TO RAMP UP TO 20-30KT FROM
NW TO SE WED/WED NIGHT. NOT OUT OF THE QUESTION THAT THERE COULD BE
SOME GALE FORCE GUSTS OVER THE CNTRL PORTION OF LAKE SUPERIOR. WINDS
WILL THEN DIMINISH TO UNDER 20KT W TO E THU/THU NIGHT AS HIGH PRES
RIDGE ARRIVES. WITH ANOTHER COLD FRONT PUSHING ACROSS THE UPPER LAKES
SAT...EXPECT INCREASING WINDS TO 15-25KT FRI/FRI NIGHT AHEAD OF
FRONT. BEHIND FRONT...NW WINDS MAY REACH 20-30KT LATE SAT/SUN.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY FROM 10 PM WEDNESDAY TO 1 PM EST
THURSDAY FOR MIZ006.
LAKE EFFECT SNOW ADVISORY FROM 7 PM WEDNESDAY TO 10 AM EST
THURSDAY FOR MIZ005.
LAKE EFFECT SNOW ADVISORY FROM 3 PM EST /2 PM CST/ WEDNESDAY TO
10 AM EST /9 AM CST/ THURSDAY FOR MIZ002-009.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1249 PM EST TUE NOV 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 518 AM EST TUE NOV 25 2014
CONCERNS FOCUS MAINLY ON LES TRENDS AND HEADLINES THIS MORNING.
LATEST WATER VAPOR LOOP AND RUC ANALYSIS SHOWS STRONG SHORTWAVE AND
ASSOC STORM SYSTEM LIFTING RAPIDLY NE THROUGH NRN QUEBEC EARLY THIS
MORNING AS A STRONG PACIFIC SHORTWAVE AND ASSOC 150 KT 3H JET MAX
PLOWS EAST THROUGH SRN BRITISH COLUMBIA AND SRN ALBERTA. SUBSEQUENT
MOVEMENT OF THESE TWO SHORTWAVE FEATURES ALLOWING MID-UPR LVL TROUGH
TO WEAKEN OVER THE UPPER GREAT LAKES THIS MORNING. THE WEAKENING
TROUGH AND MID-LVL DRYING FM THE WEST AS NOTED ON MODEL SNDGS HAS
ALLOWED SNOW AND LAKE ENHANCED SNOW TO DIMINISH FROM THE WEST AND
SOUTHWEST PER LATEST RADAR LOOP AND SFC OBS. AS A RESULT...HAVE
CANCELLED LES ADVISORIES OVER THE WESTERN COUNTIES AND WINTER WX
ADVISORY OVER MNM COUNTY THIS MORNING. LES CONTINUES OVER MUCH OF
THE REST OF THE ERN HALF OF THE FCST AREA WHERE LES ADVISORIES
REMAIN IN PLACE INTO EARLY AFTERNOON.
EXPECT THE LES TO GRADUALLY DIMINISH OVER THE ERN COUNTIES LATE THIS
MORNING INTO EARLY AFTERNOON AS DEEP MOISTURE AND MODERATE Q-VECT
CONVERGENCE PULLS NE WITH MOVEMENT OF QUEBEC SHORTWAVE AND CONTINUED
WEAKENING OF ASSOC MID-LVL/SFC TROUGH INTO THE UPPER LAKES. BEHIND
THE WEAKENED TROUGH...MODELS INDICATE FC RIDGE BUILDING IN FM WEST
WITH BACKING PBL WINDS AND A DRIER AIRMASS ALLOWING FOR ANY
REMAINING LES TO SHIFT TO THE KEWEENAW AND ACROSS THE OPEN LAKE LATE
THIS AFTERNOON AND TONIGHT. AS SUCH...WILL MAINTAIN CHANCE POPS FOR
MUCH OF TODAY AND INTO TONIGHT ACROSS THE KEWEENAW BUT END THE POPS
ACROSS THE FAR WEST. WILL MAINTAIN HIGHER POPS ALONG LAKE SUPERIOR
SHORELINE FAR EAST DUE TO W-NW FLOW HANGING ON FOR MUCH OF THE DAY.
EXPECT ADDITIONAL SNOW ACCUMULATION OF 2 TO LOCALLY 4 INCHES FOR
AREAS ROUGHLY ALONG AND EAST OF A LINE FM HURON MTNS/BIG BAY THROUGH
MQT TO RAPID RIVER WITH THE HIGHER ACCUMS ALONG HIGHER TERRAIN NEAR
LAKE SUPERIOR. ELSEWHERE SNOW WILL TAPER OFF FM A DUSTING TO HALF AN
INCH.
HIGH TEMPS TODAY WILL RANGE FROM THE LOWER 20S INTERIOR WEST TO
UPPER 20S EAST HALF AND OVER THE TIP OF THE KEWEENAW. POTENTIAL FOR
TEMPS TO PLUMMET NEAR ZERO TONIGHT OVER THE TYPICAL COLD SPOTS OF
THE WEST AND CENTRAL INTERIOR AS RIDGE MOVING OVERHEAD WILL RESULT
IN LIGHT WINDS AND CLEARING SKIES. FAVORED LOWER END OF MODEL TEMP
GUIDANCE USING A BLEND OF BIAS-CORRECTED ECMWF AND GEM-NH TEMPS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 416 AM EST TUE NOV 25 2014
...ACTIVE WITH FREQUENT CHANCES OF LAKE EFFECT OFF BOTH SUPERIOR AND
MICHIGAN...
BROAD TROUGHING ALOFT OVER EASTERN TWO THIRDS OF NORTH AMERICA TO
START THE LONG TERM PERIOD ON WEDNESDAY. PRIMARY SHORTWAVE AND SFC
LOW WITH SWATH OF SNOW OVER THE MID CONUS SHOULD STAY WELL TO THE
SOUTH OVER THE MIDDLE MISSISSIPPI RIVER VALLEY. SHORTWAVE IN THE
NORTHERN STREAM SLIDES FROM SOUTHERN MANITOBA TOWARD UPPER GREAT
LAKES REGION ON WEDNESDAY AFTN. EVEN THOUGH SFC LOW WILL BE WELL TO
SOUTH...TROUGHING SFC-925MB DEVELOPS VCNTY OF LK SUPERIOR AND UPR
MICHIGAN IN RESPONSE THE NORTHERN STREAM SHORTWAVE AND SHARP TEMP
GRADIENT FM NORTHERN ONTARIO TO THE UPPER GREAT LAKES. SE/S WINDS
AHEAD OF THE SFC TROUGH AND MOISTURE TO H85 WITH H85 TEMPS OF -10C
SHOULD SUPPORT SOME LAKE EFFECT OFF NORTHERN LK MICHIGAN INTO THE
EASTERN CWA. MARGINAL INSTABILITY AND LACK OF ENHANCEMENT FACTORS
SHOULD LIMIT LES INTENSITY OVER EAST CWA MOST OF WEDNESDAY. COULD
SEE INCREASE ON WEDNESDAY EVENING WITH LITTLE CHANGE IN LOW-LEVEL
WINDS AND TEMPS BUT INCREASING MOISTURE/LIFT AS THE SHORTWAVE AND
DEEP LAYER Q-VECTOR CONVERGENCE MOVES THROUGH. LATER ON WEDNESDAY
NIGHT...WINDS BECOME W-WNW BLO H85 WHICH WILL DIMINISH THE LES FOR
THE EASTERN CWA.
MEANWHILE...EXPECT LES ON THE KEWEENAW IN WESTERLY LOW-LEVEL FLOW
ON WEDNESDAY MORNING TO SHIFT TO THE AREAS OF WESTERN UPR MICHIGAN
AND EVENTUALLY NORTH CENTRAL UPR MICHIGAN ON WEDNESDAY AFTN INTO
WEDNESDAY EVENING AS WINDS TURN NORTHERLY IN WAKE OF THE SFC TROUGH
PASSAGE. NNE WINDS H95-H85 WITH NORTH WINDS AT SFC AND TEMPS AT H85
OF -15C LEADING TO DELTA T/S NEARING 20C SUPPLEMENTED WITH LARGER
SCALE FORCING FM THE SHORTWAVE COULD RESULT IN HEAVY LES FOR FAR
WEST UPR MICHIGAN...VCNTY OF GOGEBIC COUNTY...LATE WEDNESDAY AFTN
THROUGH MUCH OF WEDNESDAY NIGHT. SIMILAR POTENTIAL FOR HIGHER
TERRAIN OF BARAGA AND MARQUETTE COUNTY WEDNESDAY NIGHT THROUGH
AROUND DAYBREAK ON THANKSGIVING MORNING. SHORTWAVE LIKELY WILL
PRODUCE WIDESPREAD LGT SNOW FOR MOST OF THE CWA AWAY FM THE LAKE
EFFECT AREAS. MOISTURE LACKING WITH H7 MIXING RATIOS AROUND 1G/KG.
THROUGH AND NAM/GFS SOUNDINGS POINT TO MAYBE 6 HOURS OF SNOW AT
IMT/ESC...SO PROBABLY LOOKING AT UP TO AN INCH OF FLUFFY SNOW FOR
AREAS AWAY FM LK SUPERIOR. WINDS UP TO 30 KTS WITHIN THE MIXED LAYER
BUT DOES NOT APPEAR TO BE ESPECIALLY WINDY...SO ALTHOUGH THERE WILL
BE SOME BLSN DOES NOT SEEM THAT WILL BE WIDESPREAD.
INTO THANKSGIVING...WILL BE IMPROVING TREND TO WEATHER AWAY FM LK
SUPERIOR...BUT EXPECT LAKE EFFECT TO PERSIST THROUGH MOST OF THE DAY
ALONG LK SUPERIOR. SOUNDINGS SHOW A CHILLY AIRMASS WITH GRADUALLY
LOWERING INVERSIONS BLO 5KFT BY 00Z FRIDAY. MAX TEMPS ONLY IN THE
LOWER TEENS WEST HALF AND AROUND 20 DEGREES EAST HALF...WELL BLO
NORMAL FOR LATE NOVEMBER AND LIKELY NEAR A RECORD LOW MAX TEMP FOR
THIS DAY. TEMPS AT TOP OF INVERSION HOVER AROUND -18C THROUGH THE
DAY WHICH WILL BE PLENTY GOOD ENOUGH FOR LAKE EFFECT WITH LK
SUPERIOR WATER TEMPS NOW AROUND 3-4C. SNOW SHOULD BE FAIRLY FLUFFY
AS MAJORITY OF CLOUD BEARING LAYER WILL BE WITHIN THE DGZ. SLR/S
COULD BE PUSHING 30:1...SO THAT FLUFF COULD ADD UP QUICKLY.
CONFIDENCE INCREASING THAT WILL NEED ANOTHER ROUND OF LAKE EFFECT
SNOW HEADLINES FOR AREAS ALONG LK SUPERIOR WEDNESDAY AFTN INTO EARLY
THURSDAY. ISOLD WARNING AMOUNTS MAY OCCUR FOR HIGHER TERRAIN AREAS
FAVORED BY NNE WINDS... BUT MOSTLY EXPECT ADVY TYPE SNOWS. NO
HEADLINES THOUGH NOW WITH CURRENT LAKE EFFECT EVENT STILL RUNNING
ITS COURSE. WILL HIGHLIGHT IN THE HWO AND WITHIN THE EWHO GRAPHICS.
ONCE THE SHORTWAVE ON THANKSGIVING CLEARS THE AREA...UPPER LEVEL
FLOW FLATTENS OUT SOME...BUT STAYS WNW COMPARED TO THE WESTERLY FLOW
MODELS INDICATED 24 HR AGO. RESULT IS TIGHT BAROCLINIC ZONE AT
925-850MB STAYS TO THE WEST AND SOUTH OF UPR MICHIGAN. THUS WHEN THE
NEXT SERIES OF SHORTWAVES AND UPPER LEVEL JET PUSH ACROSS THE
NORTHERN PLAINS...MODELS NOW SHOW BAND OF MODERATE SNOW WILL STAY
MOSTLY ALONG THE BAROCLINIC ZONE TO THE SOUTH OF UPR MICHIGAN. H7
MIXING RATIOS 3-4G/KG SUGGEST WHEREVERE THAT BAND OF SNOW DEVELOPS
IT COULD BE AT LEAST MODERATE. MAIN ISSUE OVER UPR MICHIGAN FM THAT
SYSTEM MAY BE LAKE ENHANCED SNOW OVER EASTERN CWA OFF LK MICHIGAN
DUE TO FORCING FM THE SYSTEM GLANCING THE AREA...SSW WINDS
SFC-H85...AND H85 TEMPS -10C OR LOWER. MOST IDEAL LAKE ENHANCEMENT
PERIOD FRIDAY AFTN THROUGH FRIDAY EVENING OVER SOUTHERN SCHOOLCRAFT
INTO LUCE COUNTIES. INCREASED QPF/SNOW AMOUNTS MARKEDLY. LIKELY A
HEADLINE WILL BE NEEDED FOR THOSE AREAS AT LEAST FRIDAY/FRIDAY NIGHT.
ANOTHER SHORTWAVES QUICKLY FOLLOWS FOR SATURDAY. AT THIS POINT
BETTER FORCING AND THUS QPF STAYS ALONG AND NORTH OF LK SUPERIOR.
SOME INDICATION OF AT LEAST LGT PRECIP OVER THE CWA THOUGH. WARM
LAYER H8-H9 BECOMES MORE OF AN ISSUE. ECMWF WARMER THAN GFS AND
WOULD SUGGEST MOSTLY RAIN AS PTYPE OVER MUCH OF CWA BY SATURDAY
AFTN. GFS HAS MAINLY SNOW WITH A LITTLE RAIN WORKING IN OVER SCNTRL.
COULD BE FZRA IF WARMING AT SFC IS DELAYED. BLENDED TWO SOLUTIONS
FOR NOW AND CAME UP WITH HIGHER POPS NORTH AND MOSTLY SNOW IN
MORNING TRENDING TOWARD MORE RAIN/FZRA IN AFTN. FZRA MAY BE NOT AS
LONG LASTING THOUGH...ESPECIALLY IF THE WARMER ECMWF IDEA IS CORRECT
AS SFC WARMING WOULD BE MORE THAN IS SHOWN IN THIS FORECAST. EITHER
WAY...IF THE PRECIP OCCURS...COULD BE KIND OF A MESSY DEAL.
BECOMES COLDER AGAIN /H85 TEMPS -16C TO -20C/ BEHIND THAT SYSTEM TO
CLOSE THE WEEKEND. MORE LES EXPECTED FOR NW FLOW AREAS ALONG LK
SUPERIOR INTO MONDAY. CYCLONIC FLOW LACKING THOUGH AS BROAD HIGH
PRESSURE RIDGE OVER 1035MB EXPANDS FM THE NORTHERN PLAINS TO THE
GREAT LAKES. ANTICYCLONIC FLOW SHOULD LIMIT THE LES COVERAGE AND
INTENSITY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1248 PM EST TUE NOV 25 2014
DRIER AIR AND BACKING WINDS TO THE SW WITH APPROACHING WEAK SFC HIGH
PRES RIDGE WILL RESULT IN LAKE EFFECT -SHSN ENDING AND MVFR
CONDITIONS IMPROVING TO VFR AT KIWD DURING THE MID AFTN AND AT KSAW
LATE THIS AFTN. MAY YET SEE SOME BRIEF IFR CONDITIONS AT KSAW BASED
ON RADAR IMAGERY SHOWING HEAVIER SNOW SHOWERS IN NCNTRL UPPER MI.
VFR CONDITIONS WILL CONTINUE AT KIWD/KSAW TONIGHT. NEXT APPROACHING
DISTURBANCE MAY BRING SOME -SN/MVFR CONDITIONS TO KIWD LATE WED
MORNING. AT KCMX...WINDS WILL PROBABLY RETAIN ENOUGH OVERWATER
COMPONENT TO MAINTAIN MVFR CONDITIONS THRU THE NIGHT EVEN THOUGH
-SHSN SHOULD END. BEFORE THE -SHSN END...THERE MAY BE A PERIOD OF
SOMEWHAT HEAVIER SNOW SHOWERS AT KCMX THIS EVENING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EST TUE NOV 25 2014
STRONG LOW PRESSURE CONTINUES TO MOVE NE THROUGH NRN QUEBEC TODAY AS
THE GRADIENT GRADUALLY SLACKENS OVER LAKE SUPERIOR. NORTH WINDS HAVE
SUBSIDED BLO GALES OVER ERN LAKE SUPERIOR SO GALE WARNING HAS BEEN
CANCELLED. N-NW WINDS 25-30 KNOTS WILL QUICKLY DIMINISH BLO 20 KNOTS
BY THIS AFTERNOON. GENERALLY QUIET WEATHER EXPECTED FOR THE
REMAINDER OF THE WEEK...ALTHOUGH A LOW PRESSURE SYSTEM MOVING SOUTH
OF THE LAKE WED AY ALLOW FOR N-NE WINDS TO BRIEFLY GUST NEAR GALE
FORCE WED NIGHT INTO EARLY THU. HIGH PRESSURE BY THE WEEKEND SHOULD
ALLOW FOR WINDS LESS THAN 20 KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW WARNING UNTIL 2 PM EST THIS AFTERNOON FOR
MIZ006.
LAKE EFFECT SNOW ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR
MIZ007-013-014-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
750 AM EST TUE NOV 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 518 AM EST TUE NOV 25 2014
CONCERNS FOCUS MAINLY ON LES TRENDS AND HEADLINES THIS MORNING.
LATEST WATER VAPOR LOOP AND RUC ANALYSIS SHOWS STRONG SHORTWAVE AND
ASSOC STORM SYSTEM LIFTING RAPIDLY NE THROUGH NRN QUEBEC EARLY THIS
MORNING AS A STRONG PACIFIC SHORTWAVE AND ASSOC 150 KT 3H JET MAX
PLOWS EAST THROUGH SRN BRITISH COLUMBIA AND SRN ALBERTA. SUBSEQUENT
MOVEMENT OF THESE TWO SHORTWAVE FEATURES ALLOWING MID-UPR LVL TROUGH
TO WEAKEN OVER THE UPPER GREAT LAKES THIS MORNING. THE WEAKENING
TROUGH AND MID-LVL DRYING FM THE WEST AS NOTED ON MODEL SNDGS HAS
ALLOWED SNOW AND LAKE ENHANCED SNOW TO DIMINISH FROM THE WEST AND
SOUTHWEST PER LATEST RADAR LOOP AND SFC OBS. AS A RESULT...HAVE
CANCELLED LES ADVISORIES OVER THE WESTERN COUNTIES AND WINTER WX
ADVISORY OVER MNM COUNTY THIS MORNING. LES CONTINUES OVER MUCH OF
THE REST OF THE ERN HALF OF THE FCST AREA WHERE LES ADVISORIES
REMAIN IN PLACE INTO EARLY AFTERNOON.
EXPECT THE LES TO GRADUALLY DIMINISH OVER THE ERN COUNTIES LATE THIS
MORNING INTO EARLY AFTERNOON AS DEEP MOISTURE AND MODERATE Q-VECT
CONVERGENCE PULLS NE WITH MOVEMENT OF QUEBEC SHORTWAVE AND CONTINUED
WEAKENING OF ASSOC MID-LVL/SFC TROUGH INTO THE UPPER LAKES. BEHIND
THE WEAKENED TROUGH...MODELS INDICATE FC RIDGE BUILDING IN FM WEST
WITH BACKING PBL WINDS AND A DRIER AIRMASS ALLOWING FOR ANY
REMAINING LES TO SHIFT TO THE KEWEENAW AND ACROSS THE OPEN LAKE LATE
THIS AFTERNOON AND TONIGHT. AS SUCH...WILL MAINTAIN CHANCE POPS FOR
MUCH OF TODAY AND INTO TONIGHT ACROSS THE KEWEENAW BUT END THE POPS
ACROSS THE FAR WEST. WILL MAINTAIN HIGHER POPS ALONG LAKE SUPERIOR
SHORELINE FAR EAST DUE TO W-NW FLOW HANGING ON FOR MUCH OF THE DAY.
EXPECT ADDITIONAL SNOW ACCUMULATION OF 2 TO LOCALLY 4 INCHES FOR
AREAS ROUGHLY ALONG AND EAST OF A LINE FM HURON MTNS/BIG BAY THROUGH
MQT TO RAPID RIVER WITH THE HIGHER ACCUMS ALONG HIGHER TERRAIN NEAR
LAKE SUPERIOR. ELSEWHERE SNOW WILL TAPER OFF FM A DUSTING TO HALF AN
INCH.
HIGH TEMPS TODAY WILL RANGE FROM THE LOWER 20S INTERIOR WEST TO
UPPER 20S EAST HALF AND OVER THE TIP OF THE KEWEENAW. POTENTIAL FOR
TEMPS TO PLUMMET NEAR ZERO TONIGHT OVER THE TYPICAL COLD SPOTS OF
THE WEST AND CENTRAL INTERIOR AS RIDGE MOVING OVERHEAD WILL RESULT
IN LIGHT WINDS AND CLEARING SKIES. FAVORED LOWER END OF MODEL TEMP
GUIDANCE USING A BLEND OF BIAS-CORRECTED ECMWF AND GEM-NH TEMPS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 416 AM EST TUE NOV 25 2014
...ACTIVE WITH FREQUENT CHANCES OF LAKE EFFECT OFF BOTH SUPERIOR AND
MICHIGAN...
BROAD TROUGHING ALOFT OVER EASTERN TWO THIRDS OF NORTH AMERICA TO
START THE LONG TERM PERIOD ON WEDNESDAY. PRIMARY SHORTWAVE AND SFC
LOW WITH SWATH OF SNOW OVER THE MID CONUS SHOULD STAY WELL TO THE
SOUTH OVER THE MIDDLE MISSISSIPPI RIVER VALLEY. SHORTWAVE IN THE
NORTHERN STREAM SLIDES FROM SOUTHERN MANITOBA TOWARD UPPER GREAT
LAKES REGION ON WEDNESDAY AFTN. EVEN THOUGH SFC LOW WILL BE WELL TO
SOUTH...TROUGHING SFC-925MB DEVELOPS VCNTY OF LK SUPERIOR AND UPR
MICHIGAN IN RESPONSE THE NORTHERN STREAM SHORTWAVE AND SHARP TEMP
GRADIENT FM NORTHERN ONTARIO TO THE UPPER GREAT LAKES. SE/S WINDS
AHEAD OF THE SFC TROUGH AND MOISTURE TO H85 WITH H85 TEMPS OF -10C
SHOULD SUPPORT SOME LAKE EFFECT OFF NORTHERN LK MICHIGAN INTO THE
EASTERN CWA. MARGINAL INSTABILITY AND LACK OF ENHANCEMENT FACTORS
SHOULD LIMIT LES INTENSITY OVER EAST CWA MOST OF WEDNESDAY. COULD
SEE INCREASE ON WEDNESDAY EVENING WITH LITTLE CHANGE IN LOW-LEVEL
WINDS AND TEMPS BUT INCREASING MOISTURE/LIFT AS THE SHORTWAVE AND
DEEP LAYER Q-VECTOR CONVERGENCE MOVES THROUGH. LATER ON WEDNESDAY
NIGHT...WINDS BECOME W-WNW BLO H85 WHICH WILL DIMINISH THE LES FOR
THE EASTERN CWA.
MEANWHILE...EXPECT LES ON THE KEWEENAW IN WESTERLY LOW-LEVEL FLOW
ON WEDNESDAY MORNING TO SHIFT TO THE AREAS OF WESTERN UPR MICHIGAN
AND EVENTUALLY NORTH CENTRAL UPR MICHIGAN ON WEDNESDAY AFTN INTO
WEDNESDAY EVENING AS WINDS TURN NORTHERLY IN WAKE OF THE SFC TROUGH
PASSAGE. NNE WINDS H95-H85 WITH NORTH WINDS AT SFC AND TEMPS AT H85
OF -15C LEADING TO DELTA T/S NEARING 20C SUPPLEMENTED WITH LARGER
SCALE FORCING FM THE SHORTWAVE COULD RESULT IN HEAVY LES FOR FAR
WEST UPR MICHIGAN...VCNTY OF GOGEBIC COUNTY...LATE WEDNESDAY AFTN
THROUGH MUCH OF WEDNESDAY NIGHT. SIMILAR POTENTIAL FOR HIGHER
TERRAIN OF BARAGA AND MARQUETTE COUNTY WEDNESDAY NIGHT THROUGH
AROUND DAYBREAK ON THANKSGIVING MORNING. SHORTWAVE LIKELY WILL
PRODUCE WIDESPREAD LGT SNOW FOR MOST OF THE CWA AWAY FM THE LAKE
EFFECT AREAS. MOISTURE LACKING WITH H7 MIXING RATIOS AROUND 1G/KG.
THROUGH AND NAM/GFS SOUNDINGS POINT TO MAYBE 6 HOURS OF SNOW AT
IMT/ESC...SO PROBABLY LOOKING AT UP TO AN INCH OF FLUFFY SNOW FOR
AREAS AWAY FM LK SUPERIOR. WINDS UP TO 30 KTS WITHIN THE MIXED LAYER
BUT DOES NOT APPEAR TO BE ESPECIALLY WINDY...SO ALTHOUGH THERE WILL
BE SOME BLSN DOES NOT SEEM THAT WILL BE WIDESPREAD.
INTO THANKSGIVING...WILL BE IMPROVING TREND TO WEATHER AWAY FM LK
SUPERIOR...BUT EXPECT LAKE EFFECT TO PERSIST THROUGH MOST OF THE DAY
ALONG LK SUPERIOR. SOUNDINGS SHOW A CHILLY AIRMASS WITH GRADUALLY
LOWERING INVERSIONS BLO 5KFT BY 00Z FRIDAY. MAX TEMPS ONLY IN THE
LOWER TEENS WEST HALF AND AROUND 20 DEGREES EAST HALF...WELL BLO
NORMAL FOR LATE NOVEMBER AND LIKELY NEAR A RECORD LOW MAX TEMP FOR
THIS DAY. TEMPS AT TOP OF INVERSION HOVER AROUND -18C THROUGH THE
DAY WHICH WILL BE PLENTY GOOD ENOUGH FOR LAKE EFFECT WITH LK
SUPERIOR WATER TEMPS NOW AROUND 3-4C. SNOW SHOULD BE FAIRLY FLUFFY
AS MAJORITY OF CLOUD BEARING LAYER WILL BE WITHIN THE DGZ. SLR/S
COULD BE PUSHING 30:1...SO THAT FLUFF COULD ADD UP QUICKLY.
CONFIDENCE INCREASING THAT WILL NEED ANOTHER ROUND OF LAKE EFFECT
SNOW HEADLINES FOR AREAS ALONG LK SUPERIOR WEDNESDAY AFTN INTO EARLY
THURSDAY. ISOLD WARNING AMOUNTS MAY OCCUR FOR HIGHER TERRAIN AREAS
FAVORED BY NNE WINDS... BUT MOSTLY EXPECT ADVY TYPE SNOWS. NO
HEADLINES THOUGH NOW WITH CURRENT LAKE EFFECT EVENT STILL RUNNING
ITS COURSE. WILL HIGHLIGHT IN THE HWO AND WITHIN THE EWHO GRAPHICS.
ONCE THE SHORTWAVE ON THANKSGIVING CLEARS THE AREA...UPPER LEVEL
FLOW FLATTENS OUT SOME...BUT STAYS WNW COMPARED TO THE WESTERLY FLOW
MODELS INDICATED 24 HR AGO. RESULT IS TIGHT BAROCLINIC ZONE AT
925-850MB STAYS TO THE WEST AND SOUTH OF UPR MICHIGAN. THUS WHEN THE
NEXT SERIES OF SHORTWAVES AND UPPER LEVEL JET PUSH ACROSS THE
NORTHERN PLAINS...MODELS NOW SHOW BAND OF MODERATE SNOW WILL STAY
MOSTLY ALONG THE BAROCLINIC ZONE TO THE SOUTH OF UPR MICHIGAN. H7
MIXING RATIOS 3-4G/KG SUGGEST WHEREVERE THAT BAND OF SNOW DEVELOPS
IT COULD BE AT LEAST MODERATE. MAIN ISSUE OVER UPR MICHIGAN FM THAT
SYSTEM MAY BE LAKE ENHANCED SNOW OVER EASTERN CWA OFF LK MICHIGAN
DUE TO FORCING FM THE SYSTEM GLANCING THE AREA...SSW WINDS
SFC-H85...AND H85 TEMPS -10C OR LOWER. MOST IDEAL LAKE ENHANCEMENT
PERIOD FRIDAY AFTN THROUGH FRIDAY EVENING OVER SOUTHERN SCHOOLCRAFT
INTO LUCE COUNTIES. INCREASED QPF/SNOW AMOUNTS MARKEDLY. LIKELY A
HEADLINE WILL BE NEEDED FOR THOSE AREAS AT LEAST FRIDAY/FRIDAY NIGHT.
ANOTHER SHORTWAVES QUICKLY FOLLOWS FOR SATURDAY. AT THIS POINT
BETTER FORCING AND THUS QPF STAYS ALONG AND NORTH OF LK SUPERIOR.
SOME INDICATION OF AT LEAST LGT PRECIP OVER THE CWA THOUGH. WARM
LAYER H8-H9 BECOMES MORE OF AN ISSUE. ECMWF WARMER THAN GFS AND
WOULD SUGGEST MOSTLY RAIN AS PTYPE OVER MUCH OF CWA BY SATURDAY
AFTN. GFS HAS MAINLY SNOW WITH A LITTLE RAIN WORKING IN OVER SCNTRL.
COULD BE FZRA IF WARMING AT SFC IS DELAYED. BLENDED TWO SOLUTIONS
FOR NOW AND CAME UP WITH HIGHER POPS NORTH AND MOSTLY SNOW IN
MORNING TRENDING TOWARD MORE RAIN/FZRA IN AFTN. FZRA MAY BE NOT AS
LONG LASTING THOUGH...ESPECIALLY IF THE WARMER ECMWF IDEA IS CORRECT
AS SFC WARMING WOULD BE MORE THAN IS SHOWN IN THIS FORECAST. EITHER
WAY...IF THE PRECIP OCCURS...COULD BE KIND OF A MESSY DEAL.
BECOMES COLDER AGAIN /H85 TEMPS -16C TO -20C/ BEHIND THAT SYSTEM TO
CLOSE THE WEEKEND. MORE LES EXPECTED FOR NW FLOW AREAS ALONG LK
SUPERIOR INTO MONDAY. CYCLONIC FLOW LACKING THOUGH AS BROAD HIGH
PRESSURE RIDGE OVER 1035MB EXPANDS FM THE NORTHERN PLAINS TO THE
GREAT LAKES. ANTICYCLONIC FLOW SHOULD LIMIT THE LES COVERAGE AND
INTENSITY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 740 AM EST TUE NOV 25 2014
IFR CONDITIONS AT KSAW WILL IMPROVE TO MVFR BY LATE MORNING AND TO
VFR BY LATE AFTERNOON AS DRIER AIR MOVES IN FM THE WEST. MVFR
CONDITIONS AS BOTH KIWD AND KCMX WILL IMPROVE TO VFR LATE
AFTERNOON/EARLY EVENING AS BACKING WINDS PUSH LAKE EFFECT SNOW BANDS
WELL OFFSHORE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EST TUE NOV 25 2014
STRONG LOW PRESSURE CONTINUES TO MOVE NE THROUGH NRN QUEBEC TODAY AS
THE GRADIENT GRADUALLY SLACKENS OVER LAKE SUPERIOR. NORTH WINDS HAVE
SUBSIDED BLO GALES OVER ERN LAKE SUPERIOR SO GALE WARNING HAS BEEN
CANCELLED. N-NW WINDS 25-30 KNOTS WILL QUICKLY DIMINISH BLO 20 KNOTS
BY THIS AFTERNOON. GENERALLY QUIET WEATHER EXPECTED FOR THE
REMAINDER OF THE WEEK...ALTHOUGH A LOW PRESSURE SYSTEM MOVING SOUTH
OF THE LAKE WED AY ALLOW FOR N-NE WINDS TO BRIEFLY GUST NEAR GALE
FORCE WED NIGHT INTO EARLY THU. HIGH PRESSURE BY THE WEEKEND SHOULD
ALLOW FOR WINDS LESS THAN 20 KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ006-007-085.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ004-005.
LAKE EFFECT SNOW ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MIZ013-014.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
519 AM EST TUE NOV 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 518 AM EST TUE NOV 25 2014
CONCERNS FOCUS MAINLY ON LES TRENDS AND HEADLINES THIS MORNING.
LATEST WATER VAPOR LOOP AND RUC ANALYSIS SHOWS STRONG SHORTWAVE AND
ASSOC STORM SYSTEM LIFTING RAPIDLY NE THROUGH NRN QUEBEC EARLY THIS
MORNING AS A STRONG PACIFIC SHORTWAVE AND ASSOC 150 KT 3H JET MAX
PLOWS EAST THROUGH SRN BRITISH COLUMBIA AND SRN ALBERTA. SUBSEQUENT
MOVEMENT OF THESE TWO SHORTWAVE FEATURES ALLOWING MID-UPR LVL TROUGH
TO WEAKEN OVER THE UPPER GREAT LAKES THIS MORNING. THE WEAKENING
TROUGH AND MID-LVL DRYING FM THE WEST AS NOTED ON MODEL SNDGS HAS
ALLOWED SNOW AND LAKE ENHANCED SNOW TO DIMINISH FROM THE WEST AND
SOUTHWEST PER LATEST RADAR LOOP AND SFC OBS. AS A RESULT...HAVE
CANCELLED LES ADVISORIES OVER THE WESTERN COUNTIES AND WINTER WX
ADVISORY OVER MNM COUNTY THIS MORNING. LES CONTINUES OVER MUCH OF
THE REST OF THE ERN HALF OF THE FCST AREA WHERE LES ADVISORIES
REMAIN IN PLACE INTO EARLY AFTERNOON.
EXPECT THE LES TO GRADUALLY DIMINISH OVER THE ERN COUNTIES LATE THIS
MORNING INTO EARLY AFTERNOON AS DEEP MOISTURE AND MODERATE Q-VECT
CONVERGENCE PULLS NE WITH MOVEMENT OF QUEBEC SHORTWAVE AND CONTINUED
WEAKENING OF ASSOC MID-LVL/SFC TROUGH INTO THE UPPER LAKES. BEHIND
THE WEAKENED TROUGH...MODELS INDICATE FC RIDGE BUILDING IN FM WEST
WITH BACKING PBL WINDS AND A DRIER AIRMASS ALLOWING FOR ANY
REMAINING LES TO SHIFT TO THE KEWEENAW AND ACROSS THE OPEN LAKE LATE
THIS AFTERNOON AND TONIGHT. AS SUCH...WILL MAINTAIN CHANCE POPS FOR
MUCH OF TODAY AND INTO TONIGHT ACROSS THE KEWEENAW BUT END THE POPS
ACROSS THE FAR WEST. WILL MAINTAIN HIGHER POPS ALONG LAKE SUPERIOR
SHORELINE FAR EAST DUE TO W-NW FLOW HANGING ON FOR MUCH OF THE DAY.
EXPECT ADDITIONAL SNOW ACCUMULATION OF 2 TO LOCALLY 4 INCHES FOR
AREAS ROUGHLY ALONG AND EAST OF A LINE FM HURON MTNS/BIG BAY THROUGH
MQT TO RAPID RIVER WITH THE HIGHER ACCUMS ALONG HIGHER TERRAIN NEAR
LAKE SUPERIOR. ELSEWHERE SNOW WILL TAPER OFF FM A DUSTING TO HALF AN
INCH.
HIGH TEMPS TODAY WILL RANGE FROM THE LOWER 20S INTERIOR WEST TO
UPPER 20S EAST HALF AND OVER THE TIP OF THE KEWEENAW. POTENTIAL FOR
TEMPS TO PLUMMET NEAR ZERO TONIGHT OVER THE TYPICAL COLD SPOTS OF
THE WEST AND CENTRAL INTERIOR AS RIDGE MOVING OVERHEAD WILL RESULT
IN LIGHT WINDS AND CLEARING SKIES. FAVORED LOWER END OF MODEL TEMP
GUIDANCE USING A BLEND OF BIAS-CORRECTED ECMWF AND GEM-NH TEMPS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 416 AM EST TUE NOV 25 2014
...ACTIVE WITH FREQUENT CHANCES OF LAKE EFFECT OFF BOTH SUPERIOR AND
MICHIGAN...
BROAD TROUGHING ALOFT OVER EASTERN TWO THIRDS OF NORTH AMERICA TO
START THE LONG TERM PERIOD ON WEDNESDAY. PRIMARY SHORTWAVE AND SFC
LOW WITH SWATH OF SNOW OVER THE MID CONUS SHOULD STAY WELL TO THE
SOUTH OVER THE MIDDLE MISSISSIPPI RIVER VALLEY. SHORTWAVE IN THE
NORTHERN STREAM SLIDES FROM SOUTHERN MANITOBA TOWARD UPPER GREAT
LAKES REGION ON WEDNESDAY AFTN. EVEN THOUGH SFC LOW WILL BE WELL TO
SOUTH...TROUGHING SFC-925MB DEVELOPS VCNTY OF LK SUPERIOR AND UPR
MICHIGAN IN RESPONSE THE NORTHERN STREAM SHORTWAVE AND SHARP TEMP
GRADIENT FM NORTHERN ONTARIO TO THE UPPER GREAT LAKES. SE/S WINDS
AHEAD OF THE SFC TROUGH AND MOISTURE TO H85 WITH H85 TEMPS OF -10C
SHOULD SUPPORT SOME LAKE EFFECT OFF NORTHERN LK MICHIGAN INTO THE
EASTERN CWA. MARGINAL INSTABILITY AND LACK OF ENHANCEMENT FACTORS
SHOULD LIMIT LES INTENSITY OVER EAST CWA MOST OF WEDNESDAY. COULD
SEE INCREASE ON WEDNESDAY EVENING WITH LITTLE CHANGE IN LOW-LEVEL
WINDS AND TEMPS BUT INCREASING MOISTURE/LIFT AS THE SHORTWAVE AND
DEEP LAYER Q-VECTOR CONVERGENCE MOVES THROUGH. LATER ON WEDNESDAY
NIGHT...WINDS BECOME W-WNW BLO H85 WHICH WILL DIMINISH THE LES FOR
THE EASTERN CWA.
MEANWHILE...EXPECT LES ON THE KEWEENAW IN WESTERLY LOW-LEVEL FLOW
ON WEDNESDAY MORNING TO SHIFT TO THE AREAS OF WESTERN UPR MICHIGAN
AND EVENTUALLY NORTH CENTRAL UPR MICHIGAN ON WEDNESDAY AFTN INTO
WEDNESDAY EVENING AS WINDS TURN NORTHERLY IN WAKE OF THE SFC TROUGH
PASSAGE. NNE WINDS H95-H85 WITH NORTH WINDS AT SFC AND TEMPS AT H85
OF -15C LEADING TO DELTA T/S NEARING 20C SUPPLEMENTED WITH LARGER
SCALE FORCING FM THE SHORTWAVE COULD RESULT IN HEAVY LES FOR FAR
WEST UPR MICHIGAN...VCNTY OF GOGEBIC COUNTY...LATE WEDNESDAY AFTN
THROUGH MUCH OF WEDNESDAY NIGHT. SIMILAR POTENTIAL FOR HIGHER
TERRAIN OF BARAGA AND MARQUETTE COUNTY WEDNESDAY NIGHT THROUGH
AROUND DAYBREAK ON THANKSGIVING MORNING. SHORTWAVE LIKELY WILL
PRODUCE WIDESPREAD LGT SNOW FOR MOST OF THE CWA AWAY FM THE LAKE
EFFECT AREAS. MOISTURE LACKING WITH H7 MIXING RATIOS AROUND 1G/KG.
THROUGH AND NAM/GFS SOUNDINGS POINT TO MAYBE 6 HOURS OF SNOW AT
IMT/ESC...SO PROBABLY LOOKING AT UP TO AN INCH OF FLUFFY SNOW FOR
AREAS AWAY FM LK SUPERIOR. WINDS UP TO 30 KTS WITHIN THE MIXED LAYER
BUT DOES NOT APPEAR TO BE ESPECIALLY WINDY...SO ALTHOUGH THERE WILL
BE SOME BLSN DOES NOT SEEM THAT WILL BE WIDESPREAD.
INTO THANKSGIVING...WILL BE IMPROVING TREND TO WEATHER AWAY FM LK
SUPERIOR...BUT EXPECT LAKE EFFECT TO PERSIST THROUGH MOST OF THE DAY
ALONG LK SUPERIOR. SOUNDINGS SHOW A CHILLY AIRMASS WITH GRADUALLY
LOWERING INVERSIONS BLO 5KFT BY 00Z FRIDAY. MAX TEMPS ONLY IN THE
LOWER TEENS WEST HALF AND AROUND 20 DEGREES EAST HALF...WELL BLO
NORMAL FOR LATE NOVEMBER AND LIKELY NEAR A RECORD LOW MAX TEMP FOR
THIS DAY. TEMPS AT TOP OF INVERSION HOVER AROUND -18C THROUGH THE
DAY WHICH WILL BE PLENTY GOOD ENOUGH FOR LAKE EFFECT WITH LK
SUPERIOR WATER TEMPS NOW AROUND 3-4C. SNOW SHOULD BE FAIRLY FLUFFY
AS MAJORITY OF CLOUD BEARING LAYER WILL BE WITHIN THE DGZ. SLR/S
COULD BE PUSHING 30:1...SO THAT FLUFF COULD ADD UP QUICKLY.
CONFIDENCE INCREASING THAT WILL NEED ANOTHER ROUND OF LAKE EFFECT
SNOW HEADLINES FOR AREAS ALONG LK SUPERIOR WEDNESDAY AFTN INTO EARLY
THURSDAY. ISOLD WARNING AMOUNTS MAY OCCUR FOR HIGHER TERRAIN AREAS
FAVORED BY NNE WINDS... BUT MOSTLY EXPECT ADVY TYPE SNOWS. NO
HEADLINES THOUGH NOW WITH CURRENT LAKE EFFECT EVENT STILL RUNNING
ITS COURSE. WILL HIGHLIGHT IN THE HWO AND WITHIN THE EWHO GRAPHICS.
ONCE THE SHORTWAVE ON THANKSGIVING CLEARS THE AREA...UPPER LEVEL
FLOW FLATTENS OUT SOME...BUT STAYS WNW COMPARED TO THE WESTERLY FLOW
MODELS INDICATED 24 HR AGO. RESULT IS TIGHT BAROCLINIC ZONE AT
925-850MB STAYS TO THE WEST AND SOUTH OF UPR MICHIGAN. THUS WHEN THE
NEXT SERIES OF SHORTWAVES AND UPPER LEVEL JET PUSH ACROSS THE
NORTHERN PLAINS...MODELS NOW SHOW BAND OF MODERATE SNOW WILL STAY
MOSTLY ALONG THE BAROCLINIC ZONE TO THE SOUTH OF UPR MICHIGAN. H7
MIXING RATIOS 3-4G/KG SUGGEST WHEREVERE THAT BAND OF SNOW DEVELOPS
IT COULD BE AT LEAST MODERATE. MAIN ISSUE OVER UPR MICHIGAN FM THAT
SYSTEM MAY BE LAKE ENHANCED SNOW OVER EASTERN CWA OFF LK MICHIGAN
DUE TO FORCING FM THE SYSTEM GLANCING THE AREA...SSW WINDS
SFC-H85...AND H85 TEMPS -10C OR LOWER. MOST IDEAL LAKE ENHANCEMENT
PERIOD FRIDAY AFTN THROUGH FRIDAY EVENING OVER SOUTHERN SCHOOLCRAFT
INTO LUCE COUNTIES. INCREASED QPF/SNOW AMOUNTS MARKEDLY. LIKELY A
HEADLINE WILL BE NEEDED FOR THOSE AREAS AT LEAST FRIDAY/FRIDAY NIGHT.
ANOTHER SHORTWAVES QUICKLY FOLLOWS FOR SATURDAY. AT THIS POINT
BETTER FORCING AND THUS QPF STAYS ALONG AND NORTH OF LK SUPERIOR.
SOME INDICATION OF AT LEAST LGT PRECIP OVER THE CWA THOUGH. WARM
LAYER H8-H9 BECOMES MORE OF AN ISSUE. ECMWF WARMER THAN GFS AND
WOULD SUGGEST MOSTLY RAIN AS PTYPE OVER MUCH OF CWA BY SATURDAY
AFTN. GFS HAS MAINLY SNOW WITH A LITTLE RAIN WORKING IN OVER SCNTRL.
COULD BE FZRA IF WARMING AT SFC IS DELAYED. BLENDED TWO SOLUTIONS
FOR NOW AND CAME UP WITH HIGHER POPS NORTH AND MOSTLY SNOW IN
MORNING TRENDING TOWARD MORE RAIN/FZRA IN AFTN. FZRA MAY BE NOT AS
LONG LASTING THOUGH...ESPECIALLY IF THE WARMER ECMWF IDEA IS CORRECT
AS SFC WARMING WOULD BE MORE THAN IS SHOWN IN THIS FORECAST. EITHER
WAY...IF THE PRECIP OCCURS...COULD BE KIND OF A MESSY DEAL.
BECOMES COLDER AGAIN /H85 TEMPS -16C TO -20C/ BEHIND THAT SYSTEM TO
CLOSE THE WEEKEND. MORE LES EXPECTED FOR NW FLOW AREAS ALONG LK
SUPERIOR INTO MONDAY. CYCLONIC FLOW LACKING THOUGH AS BROAD HIGH
PRESSURE RIDGE OVER 1035MB EXPANDS FM THE NORTHERN PLAINS TO THE
GREAT LAKES. ANTICYCLONIC FLOW SHOULD LIMIT THE LES COVERAGE AND
INTENSITY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 122 AM EST TUE NOV 25 2014
IFR CONDITIONS WILL CONTINUE THROUGH THE OVERNIGHT BEFORE IMPROVING
TO MVFR ON TUESDAY AS DRIER AIR MOVES IN. BY LATE AFTERNOON INTO
EARLY EVENING...VFR CONDITIONS WILL PREVAIL AT ALL SITES AS WINDS
PUSH LAKE EFFECT SNOW BANDS WELL OFFSHORE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 AM EST TUE NOV 25 2014
STRONG LOW PRESSURE CONTINUES TO MOVE NE THROUGH NRN QUEBEC TODAY AS
THE GRADIENT GRADUALLY SLACKENS OVER LAKE SUPERIOR. NORTH WINDS HAVE
SUBSIDED BLO GALES OVER ERN LAKE SUPERIOR SO GALE WARNING HAS BEEN
CANCELLED. N-NW WINDS 25-30 KNOTS WILL QUICKLY DIMINISH BLO 20 KNOTS
BY THIS AFTERNOON. GENERALLY QUIET WEATHER EXPECTED FOR THE
REMAINDER OF THE WEEK...ALTHOUGH A LOW PRESSURE SYSTEM MOVING SOUTH
OF THE LAKE WED AY ALLOW FOR N-NE WINDS TO BRIEFLY GUST NEAR GALE
FORCE WED NIGHT INTO EARLY THU. HIGH PRESSURE BY THE WEEKEND SHOULD
ALLOW FOR WINDS LESS THAN 20 KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ006-007-085.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ004-005.
LAKE EFFECT SNOW ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MIZ013-014.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...07
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
421 AM EST TUE NOV 25 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 358 PM EST MON NOV 24 2014
COLD AIR IS RAPIDLY MOVING ACROSS UPPER MICHIGAN. MOST PLACES EXCEPT
THE FAR SOUTH AND EAST HAVE TURNED OVER TO SNOW AS 850MB TEMPS
RAPIDLY DROP TO -12C OR LOWER BEHIND THE SFC LOW. OTHER THAN NEAR
LAKE SUPERIOR...THE REST OF THE AREA IS UNDER A LULL OF
PRECIPITATION BEHIND THE FIRST UPPER DISTURBANCE RAPIDLY MOVING NE
INTO CANADA. HOWEVER...THE SECOND WAVE OF ENERGY CURRENTLY STILL
OVER THE IOWA AND SRN WI WILL MOVE TOWARD THE AREA THIS EVENING.
MODERATE MID LEVEL Q-VECTOR CONVERGENCE ALONG WITH MODERATE
850-700MB FRONTOGENETIC FORCING OWED TO THE MID LEVEL DEFORMATION
AXIS WILL MOVE ACROSS WI AND ACROSS THE FAR SOUTHERN PART OF THE
FORECAST AREA TONIGHT. THIS WILL ALLOW FOR A PERIOD OF SYSTEM SNOW
TO SPREAD ACROSS AREAS GENERALLY ALONG AND SOUTH OF U.S. 2 IN
MENOMINEE AND DELTA COUNTIES TONIGHT. RAPID UPDATE NWP SUGGEST UP TO
0.50 INCH OF LIQUID TONIGHT /WITH THE LATEST HRRR SUGGESTING UP TO
0.75 INCH/. BUT GIVEN THAT THE SYSTEM WILL BE MOVING FAIRLY FAST TO
THE NE AND 700MB SPECIFIC HUMIDITY VALUES ARE AT MOST 3 G/KM THIS
EVENING...AM EXPECTING QPF OF SLIGHTLY LESS THAN 0.50 INCH. WITH
SNOW RATIOS RISING TO 10-15:1 THIS EVENING...THIS WOULD SUGGEST THAT
FAR SOUTHERN MENOMINEE COUNTY COULD SEE 4-6 INCHES OF SNOW STARTING
LATE THIS AFTERNOON AND CONTINUING INTO OVERNIGHT. AS SUCH...HAVE
OPTED TO ISSUE A WINTER WEATHER ADVY FOR MENOMINEE COUNTY...FOCUSING
ON AREAS MAINLY SOUTH OF US 2. AM CURRENTLY THINKING THAT SYSTEM
PCPN WILL DIMINISH OVER A RELATIVELY SHORT DISTANCE TO THE
NORTH...SO AS OF NOW WILL LEAVE DICKINSON AND DELTA COUNTIES OUT OF
THE WINTER WEATHER ADVY.
AS FOR THE REMAINDER OF THE AREA...NO MAJOR CHANGES TO THE FORECAST
PLANNED. AS THE COLDER AIR MOVES ACROSS THE AREA THIS
EVENING...EXPECT BETTER LES BANDS TO DEVELOP IN THE N-NW
FLOW...SIMILAR TO WHAT IS OCCURRING AT IWD RIGHT NOW. CURRENT SNOW
RATIOS ARE FAIRLY LOW...GENERALLY 10-15:1 DUE TO THE SNOW GROWTH
REGION STILL FAIRLY HIGH. AS THE COLDER AIR MOVES IN...THE
EXPECTATION IS THAT THE SNOW RATIOS WILL BECOME HIGHER...CLOSER TO
20:1. AS SUCH...WILL MAINTAIN ALL LAKE EFFECT SNOW ADVISORIES AS
IS...WITH SIMILAR FORECAST AMOUNTS EXPECTED. STILL EXPECTING STORM
TOTAL OF 5-8 INCHES ACROSS THE GOGEBIC RANGE...4-7 INCHES
KEWEENAW...4-9 INCHES N-CENTRAL UPPER MI...AND 4-7 INCHES EAST OF
MARQUETTE. BLOWING SNOW NEAR LAKE SUPERIOR WILL STILL BE A PROBLEM
WITH SOME GUSTS IN EXCESS OF 30 MPH.
THE LES SHOULD GRADUALLY DIMINISH FROM WEST TO EAST LATE TONIGHT
INTO TUESDAY BEHIND THE UPPER TROUGH WHICH MOVES THROUGH LATE
TONIGHT. BEHIND THIS TROUGH...WEAK SFC RIDGING BUILDS IN ALONG WITH
BACKING PBL WINDS AND A DRIER AIRMASS ALLOWING FOR ANY REMAINING LES
TO SHIFT TO THE KEWEENAW AND ACROSS THE OPEN LAKE TUE AFTN. AS
SUCH...WILL MAINTAIN CHANCE POPS FOR THE ENTIRE DAY ACROSS THE
KEWEENAW BUT END THE POPS ACROSS THE FAR WEST. WILL MAINTAIN HIGHER
POPS EAST DUE TO W-NW FLOW HANGING ON FOR MUCH OF THE DAY THERE
ALONG WITH DEEPER MOISTURE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 416 AM EST TUE NOV 25 2014
...ACTIVE WITH FREQUENT CHANCES OF LAKE EFFECT OFF BOTH SUPERIOR AND
MICHIGAN...
BROAD TROUGHING ALOFT OVER EASTERN TWO THIRDS OF NORTH AMERICA TO
START THE LONG TERM PERIOD ON WEDNESDAY. PRIMARY SHORTWAVE AND SFC
LOW WITH SWATH OF SNOW OVER THE MID CONUS SHOULD STAY WELL TO THE
SOUTH OVER THE MIDDLE MISSISSIPPI RIVER VALLEY. SHORTWAVE IN THE
NORTHERN STREAM SLIDES FROM SOUTHERN MANITOBA TOWARD UPPER GREAT
LAKES REGION ON WEDNESDAY AFTN. EVEN THOUGH SFC LOW WILL BE WELL TO
SOUTH...TROUGHING SFC-925MB DEVELOPS VCNTY OF LK SUPERIOR AND UPR
MICHIGAN IN RESPONSE THE NORTHERN STREAM SHORTWAVE AND SHARP TEMP
GRADIENT FM NORTHERN ONTARIO TO THE UPPER GREAT LAKES. SE/S WINDS
AHEAD OF THE SFC TROUGH AND MOISTURE TO H85 WITH H85 TEMPS OF -10C
SHOULD SUPPORT SOME LAKE EFFECT OFF NORTHERN LK MICHIGAN INTO THE
EASTERN CWA. MARGINAL INSTABILITY AND LACK OF ENHANCEMENT FACTORS
SHOULD LIMIT LES INTENSITY OVER EAST CWA MOST OF WEDNESDAY. COULD
SEE INCREASE ON WEDNESDAY EVENING WITH LITTLE CHANGE IN LOW-LEVEL
WINDS AND TEMPS BUT INCREASING MOISTURE/LIFT AS THE SHORTWAVE AND
DEEP LAYER Q-VECTOR CONVERGENCE MOVES THROUGH. LATER ON WEDNESDAY
NIGHT...WINDS BECOME W-WNW BLO H85 WHICH WILL DIMINISH THE LES FOR
THE EASTERN CWA.
MEANWHILE...EXPECT LES ON THE KEWEENAW IN WESTERLY LOW-LEVEL FLOW
ON WEDNESDAY MORNING TO SHIFT TO THE AREAS OF WESTERN UPR MICHIGAN
AND EVENTUALLY NORTH CENTRAL UPR MICHIGAN ON WEDNESDAY AFTN INTO
WEDNESDAY EVENING AS WINDS TURN NORTHERLY IN WAKE OF THE SFC TROUGH
PASSAGE. NNE WINDS H95-H85 WITH NORTH WINDS AT SFC AND TEMPS AT H85
OF -15C LEADING TO DELTA T/S NEARING 20C SUPPLEMENTED WITH LARGER
SCALE FORCING FM THE SHORTWAVE COULD RESULT IN HEAVY LES FOR FAR
WEST UPR MICHIGAN...VCNTY OF GOGEBIC COUNTY...LATE WEDNESDAY AFTN
THROUGH MUCH OF WEDNESDAY NIGHT. SIMILAR POTENTIAL FOR HIGHER
TERRAIN OF BARAGA AND MARQUETTE COUNTY WEDNESDAY NIGHT THROUGH
AROUND DAYBREAK ON THANKSGIVING MORNING. SHORTWAVE LIKELY WILL
PRODUCE WIDESPREAD LGT SNOW FOR MOST OF THE CWA AWAY FM THE LAKE
EFFECT AREAS. MOISTURE LACKING WITH H7 MIXING RATIOS AROUND 1G/KG.
THROUGH AND NAM/GFS SOUNDINGS POINT TO MAYBE 6 HOURS OF SNOW AT
IMT/ESC...SO PROBABLY LOOKING AT UP TO AN INCH OF FLUFFY SNOW FOR
AREAS AWAY FM LK SUPERIOR. WINDS UP TO 30 KTS WITHIN THE MIXED LAYER
BUT DOES NOT APPEAR TO BE ESPECIALLY WINDY...SO ALTHOUGH THERE WILL
BE SOME BLSN DOES NOT SEEM THAT WILL BE WIDESPREAD.
INTO THANKSGIVING...WILL BE IMPROVING TREND TO WEATHER AWAY FM LK
SUPERIOR...BUT EXPECT LAKE EFFECT TO PERSIST THROUGH MOST OF THE DAY
ALONG LK SUPERIOR. SOUNDINGS SHOW A CHILLY AIRMASS WITH GRADUALLY
LOWERING INVERSIONS BLO 5KFT BY 00Z FRIDAY. MAX TEMPS ONLY IN THE
LOWER TEENS WEST HALF AND AROUND 20 DEGREES EAST HALF...WELL BLO
NORMAL FOR LATE NOVEMBER AND LIKELY NEAR A RECORD LOW MAX TEMP FOR
THIS DAY. TEMPS AT TOP OF INVERSION HOVER AROUND -18C THROUGH THE
DAY WHICH WILL BE PLENTY GOOD ENOUGH FOR LAKE EFFECT WITH LK
SUPERIOR WATER TEMPS NOW AROUND 3-4C. SNOW SHOULD BE FAIRLY FLUFFY
AS MAJORITY OF CLOUD BEARING LAYER WILL BE WITHIN THE DGZ. SLR/S
COULD BE PUSHING 30:1...SO THAT FLUFF COULD ADD UP QUICKLY.
CONFIDENCE INCREASING THAT WILL NEED ANOTHER ROUND OF LAKE EFFECT
SNOW HEADLINES FOR AREAS ALONG LK SUPERIOR WEDNESDAY AFTN INTO EARLY
THURSDAY. ISOLD WARNING AMOUNTS MAY OCCUR FOR HIGHER TERRAIN AREAS
FAVORED BY NNE WINDS... BUT MOSTLY EXPECT ADVY TYPE SNOWS. NO
HEADLINES THOUGH NOW WITH CURRENT LAKE EFFECT EVENT STILL RUNNING
ITS COURSE. WILL HIGHLIGHT IN THE HWO AND WITHIN THE EWHO GRAPHICS.
ONCE THE SHORTWAVE ON THANKSGIVING CLEARS THE AREA...UPPER LEVEL
FLOW FLATTENS OUT SOME...BUT STAYS WNW COMPARED TO THE WESTERLY FLOW
MODELS INDICATED 24 HR AGO. RESULT IS TIGHT BAROCLINIC ZONE AT
925-850MB STAYS TO THE WEST AND SOUTH OF UPR MICHIGAN. THUS WHEN THE
NEXT SERIES OF SHORTWAVES AND UPPER LEVEL JET PUSH ACROSS THE
NORTHERN PLAINS...MODELS NOW SHOW BAND OF MODERATE SNOW WILL STAY
MOSTLY ALONG THE BAROCLINIC ZONE TO THE SOUTH OF UPR MICHIGAN. H7
MIXING RATIOS 3-4G/KG SUGGEST WHEREVERE THAT BAND OF SNOW DEVELOPS
IT COULD BE AT LEAST MODERATE. MAIN ISSUE OVER UPR MICHIGAN FM THAT
SYSTEM MAY BE LAKE ENHANCED SNOW OVER EASTERN CWA OFF LK MICHIGAN
DUE TO FORCING FM THE SYSTEM GLANCING THE AREA...SSW WINDS
SFC-H85...AND H85 TEMPS -10C OR LOWER. MOST IDEAL LAKE ENHANCEMENT
PERIOD FRIDAY AFTN THROUGH FRIDAY EVENING OVER SOUTHERN SCHOOLCRAFT
INTO LUCE COUNTIES. INCREASED QPF/SNOW AMOUNTS MARKEDLY. LIKELY A
HEADLINE WILL BE NEEDED FOR THOSE AREAS AT LEAST FRIDAY/FRIDAY NIGHT.
ANOTHER SHORTWAVES QUICKLY FOLLOWS FOR SATURDAY. AT THIS POINT
BETTER FORCING AND THUS QPF STAYS ALONG AND NORTH OF LK SUPERIOR.
SOME INDICATION OF AT LEAST LGT PRECIP OVER THE CWA THOUGH. WARM
LAYER H8-H9 BECOMES MORE OF AN ISSUE. ECMWF WARMER THAN GFS AND
WOULD SUGGEST MOSTLY RAIN AS PTYPE OVER MUCH OF CWA BY SATURDAY
AFTN. GFS HAS MAINLY SNOW WITH A LITTLE RAIN WORKING IN OVER SCNTRL.
COULD BE FZRA IF WARMING AT SFC IS DELAYED. BLENDED TWO SOLUTIONS
FOR NOW AND CAME UP WITH HIGHER POPS NORTH AND MOSTLY SNOW IN
MORNING TRENDING TOWARD MORE RAIN/FZRA IN AFTN. FZRA MAY BE NOT AS
LONG LASTING THOUGH...ESPECIALLY IF THE WARMER ECMWF IDEA IS CORRECT
AS SFC WARMING WOULD BE MORE THAN IS SHOWN IN THIS FORECAST. EITHER
WAY...IF THE PRECIP OCCURS...COULD BE KIND OF A MESSY DEAL.
BECOMES COLDER AGAIN /H85 TEMPS -16C TO -20C/ BEHIND THAT SYSTEM TO
CLOSE THE WEEKEND. MORE LES EXPECTED FOR NW FLOW AREAS ALONG LK
SUPERIOR INTO MONDAY. CYCLONIC FLOW LACKING THOUGH AS BROAD HIGH
PRESSURE RIDGE OVER 1035MB EXPANDS FM THE NORTHERN PLAINS TO THE
GREAT LAKES. ANTICYCLONIC FLOW SHOULD LIMIT THE LES COVERAGE AND
INTENSITY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 122 AM EST TUE NOV 25 2014
IFR CONDITIONS WILL CONTINUE THROUGH THE OVERNIGHT BEFORE IMPROVING
TO MVFR ON TUESDAY AS DRIER AIR MOVES IN. BY LATE AFTERNOON INTO
EARLY EVENING...VFR CONDITIONS WILL PREVAIL AT ALL SITES AS WINDS
PUSH LAKE EFFECT SNOW BANDS WELL OFFSHORE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 358 PM EST MON NOV 24 2014
STRONG LOW PRESSURE NEAR SAULT STE MARIE JUST SOUTH OF JAMES BAY
WILL RAPIDLY MOVE INTO NRN QUEBEC TONIGHT. N-NW GALES WILL PERSIST
ACROSS THE LAKE TONIGHT...THEN SUBSIDE RATHER QUICKLY TUESDAY
MORNING. GENERALLY QUIET WEATHER EXPECTED FOR THE REMAINDER OF THE
WEEK...ALTHOUGH A LOW PRESSURE SYSTEM MOVING SOUTH OF THE LAKE WED
INTO WED NIGHT MAY ALLOW FOR N-NE WINDS TO GUST TO NEAR GALE FORCE.
HIGH PRESSURE BY THE WEEKEND SHOULD ALLOW FOR WINDS LESS THAN 20 KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ006-007-085.
LAKESHORE FLOOD ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
MIZ001-003-005>007.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ004-005.
LAKE EFFECT SNOW ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MIZ013-014.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...MRD
LONG TERM...JLA
AVIATION...07
MARINE...MRD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
122 AM EST TUE NOV 25 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 358 PM EST MON NOV 24 2014
COLD AIR IS RAPIDLY MOVING ACROSS UPPER MICHIGAN. MOST PLACES EXCEPT
THE FAR SOUTH AND EAST HAVE TURNED OVER TO SNOW AS 850MB TEMPS
RAPIDLY DROP TO -12C OR LOWER BEHIND THE SFC LOW. OTHER THAN NEAR
LAKE SUPERIOR...THE REST OF THE AREA IS UNDER A LULL OF
PRECIPITATION BEHIND THE FIRST UPPER DISTURBANCE RAPIDLY MOVING NE
INTO CANADA. HOWEVER...THE SECOND WAVE OF ENERGY CURRENTLY STILL
OVER THE IOWA AND SRN WI WILL MOVE TOWARD THE AREA THIS EVENING.
MODERATE MID LEVEL Q-VECTOR CONVERGENCE ALONG WITH MODERATE
850-700MB FRONTOGENETIC FORCING OWED TO THE MID LEVEL DEFORMATION
AXIS WILL MOVE ACROSS WI AND ACROSS THE FAR SOUTHERN PART OF THE
FORECAST AREA TONIGHT. THIS WILL ALLOW FOR A PERIOD OF SYSTEM SNOW
TO SPREAD ACROSS AREAS GENERALLY ALONG AND SOUTH OF U.S. 2 IN
MENOMINEE AND DELTA COUNTIES TONIGHT. RAPID UPDATE NWP SUGGEST UP TO
0.50 INCH OF LIQUID TONIGHT /WITH THE LATEST HRRR SUGGESTING UP TO
0.75 INCH/. BUT GIVEN THAT THE SYSTEM WILL BE MOVING FAIRLY FAST TO
THE NE AND 700MB SPECIFIC HUMIDITY VALUES ARE AT MOST 3 G/KM THIS
EVENING...AM EXPECTING QPF OF SLIGHTLY LESS THAN 0.50 INCH. WITH
SNOW RATIOS RISING TO 10-15:1 THIS EVENING...THIS WOULD SUGGEST THAT
FAR SOUTHERN MENOMINEE COUNTY COULD SEE 4-6 INCHES OF SNOW STARTING
LATE THIS AFTERNOON AND CONTINUING INTO OVERNIGHT. AS SUCH...HAVE
OPTED TO ISSUE A WINTER WEATHER ADVY FOR MENOMINEE COUNTY...FOCUSING
ON AREAS MAINLY SOUTH OF US 2. AM CURRENTLY THINKING THAT SYSTEM
PCPN WILL DIMINISH OVER A RELATIVELY SHORT DISTANCE TO THE
NORTH...SO AS OF NOW WILL LEAVE DICKINSON AND DELTA COUNTIES OUT OF
THE WINTER WEATHER ADVY.
AS FOR THE REMAINDER OF THE AREA...NO MAJOR CHANGES TO THE FORECAST
PLANNED. AS THE COLDER AIR MOVES ACROSS THE AREA THIS
EVENING...EXPECT BETTER LES BANDS TO DEVELOP IN THE N-NW
FLOW...SIMILAR TO WHAT IS OCCURRING AT IWD RIGHT NOW. CURRENT SNOW
RATIOS ARE FAIRLY LOW...GENERALLY 10-15:1 DUE TO THE SNOW GROWTH
REGION STILL FAIRLY HIGH. AS THE COLDER AIR MOVES IN...THE
EXPECTATION IS THAT THE SNOW RATIOS WILL BECOME HIGHER...CLOSER TO
20:1. AS SUCH...WILL MAINTAIN ALL LAKE EFFECT SNOW ADVISORIES AS
IS...WITH SIMILAR FORECAST AMOUNTS EXPECTED. STILL EXPECTING STORM
TOTAL OF 5-8 INCHES ACROSS THE GOGEBIC RANGE...4-7 INCHES
KEWEENAW...4-9 INCHES N-CENTRAL UPPER MI...AND 4-7 INCHES EAST OF
MARQUETTE. BLOWING SNOW NEAR LAKE SUPERIOR WILL STILL BE A PROBLEM
WITH SOME GUSTS IN EXCESS OF 30 MPH.
THE LES SHOULD GRADUALLY DIMINISH FROM WEST TO EAST LATE TONIGHT
INTO TUESDAY BEHIND THE UPPER TROUGH WHICH MOVES THROUGH LATE
TONIGHT. BEHIND THIS TROUGH...WEAK SFC RIDGING BUILDS IN ALONG WITH
BACKING PBL WINDS AND A DRIER AIRMASS ALLOWING FOR ANY REMAINING LES
TO SHIFT TO THE KEWEENAW AND ACROSS THE OPEN LAKE TUE AFTN. AS
SUCH...WILL MAINTAIN CHANCE POPS FOR THE ENTIRE DAY ACROSS THE
KEWEENAW BUT END THE POPS ACROSS THE FAR WEST. WILL MAINTAIN HIGHER
POPS EAST DUE TO W-NW FLOW HANGING ON FOR MUCH OF THE DAY THERE
ALONG WITH DEEPER MOISTURE.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 408 PM EST MON NOV 24 2014
MAIN FCST CONCERNS IN THE LONGER TERM WL BE FOCUSED ON THE POTENTIAL
FOR AT LEAST SOME MARGINAL ADVY LES TOTALS ON WED INTO EARLY
THANKSGIVING ASSOCIATED WITH A SHRTWV DIGGING SEWD THRU THE UPR LKS.
FORTUNATELY FOR THOSE INTERESTED IN TRAVEL ON THANKSGIVING...MODELS
HAVE CONTINUED TREND TOWARD LESS PHASING BTWN A PAIR OF SHRTWVS THAT
WL LIMIT THE POTENTIAL FOR HEAVIER SN AWAY FM LK SUP. TEMPS WL RUN
BLO TO WELL BLO NORMAL ON TUE NGT INTO FRI WITH AN UPR TROF
DEEPENING OVER ERN NAMERICA. AS THIS TROF GIVES WAY TO A MORE ZONAL
FLOW THIS WEEKEND...A MORE CHANGEABLE PATTERN WL DOMINATE WITH
WARMER AIR IN STORE FOR SAT.
TUE NGT...A WEAK SFC HI PRES UNDER SUBTLE SHRTWV RDGING/AREA OF DEEP
LYR QVECTOR DVGC WL DOMINATE MOST OF THE NGT AND BRING DRY WX TO
MOST OF THE CWA. THE BEST CHC FOR SOME PCPN WL BE OVER THE NW CWA
NEAR A STATIONARY FNT ORIENTED W-E OVER LK SUP. H85 TEMPS ANRD -13C
MAY SUPPORT A LK EFFECT COMPONENT...ESPECIALLY LATE WHEN SOME DPVA/
DEEP LYR QVECTOR CNVGC IN ADVANCE OF A SHRTWV DIGGING SEWD TOWARD
THE CNDN/MN BORDER IS FCST TO ARRIVE. EXPECT THE LOWEST MIN TEMPS
OVER THE INTERIOR SCENTRAL AND E WHERE THE NEGATIVE DYNAMICS SHOULD
LINGER THRU THE NGT IN THE PRESENCE OF PWAT UNDER 0.25 INCH AND
MINIMIZE CLD COVER EXCEPT FOR SOME HIER CLDS SPILLING INTO UPR MI
AHEAD OF THE INCOMING SHRWTV.
WED...SHRTWV APRCHG FM THE NW IS FCST TO MOVE INTO WRN LK SUP BY 00Z
THU...WITH DPVA/DEEP LYR QVECTOR CNVGC INVADING UPR MI. BUT SINCE
THE MODELS HAVE TRENDED TOWARD LESS PHASING BTWN THIS SHRTWV AND
ANOTHER STRONGER DISTURBANCE DIGGING SEWD IN THE MID MS RIVER VALLEY
THAT WL ROB THE AREA OF DEEPER MSTR AND LEAVE PWAT NO HIER THAN
ABOUT 0.25-0.30 INCH...ACCOMPANYING SN OVER THE CWA SHOULD BE
RELATIVELY LGT. THE BEST CHC FOR MORE SN WL BE IN THE N WIND SN
BELTS NEAR LK SUP AS THE H925 FLOW SHIFTS TO THE N COINCIDENT WITH
PASSING NRN SHRTWV AND ALLOWS FOR SOME LES AS H85 TEMPS FALL TO ARND
-15C OVER THE NW BY 00Z WED. SN TOTALS IN THAT AREA MAY ALSO BE
BOOSTED A BIT BY RATHER DEEP DGZ BTWN ABOUT 4-9K FT MSL EVEN THOUGH
MORE SHARPER UVV IS NOT FCST WITHIN THAT LYR. NOT OUT OF THE
QUESTION THE FLOW MAY BACK SUFFICIENTLY TO THE SW IN ADVANCE OF THE
SHRTWV TO ALLOW FOR A PERIOD OF SOME LK EFFECT SN OFF LK MI INTO THE
SE CWA IN THE PRESENCE OF H85 TEMPS NEAR -10C.
WED NGT...STEADY NNW WIND IN THE WAKE OF PASSING SHRTWV IS FCST TO
ADVECT H85 TEMPS AS LO AS -20C OVER THE KEWEENAW BY 12Z THU. THERE
MAY BE SOME ADVY LVL LES IN THE FAVORED SN BELTS AS THERE WL BE A
PERIOD WHERE THE FAVORABLE CAA/CYC NNW FLOW IS COINCIDENT WITH
DEEPER MSTR/SOME DEEP LYR QVECTOR CNVGC THAT WL LIKELY BRING SOME
LIGHTER SN EVEN TO THE SCENTRAL. THE ARRIVAL OF SOME DNVA/DEEP LYR
QVECTOR DVGC LATER AT NGT IS PROGGED TO SHARPLY LOWER INVRN BASE
TOWARD H85...WHICH SHOULD BRING ABOUT A DIMINISHING TREND IN THE LES
OVER AT LEAST THE W HALF. THE 12Z GFS IS FASTEST WITH THIS
DIMINISHING TREND.
THANKSGIVING/THU NGT...THE LLVL FLOW IS PROGGED TO BACK STEADILY AND
TURN MORE ACYC ON THANKSGIVING WITH SFC HI PRES MOVING TOWARD WI
LATE IN THE DAY UNDER HGT RISES/DNVA IN ADVANCE OF APRCHG SHRTWV
RDG. THE RESULT WL BE SHIFTING/DIMINISHING LES BANDS...ESPECIALLY
OVER THE W HALF. THE LES WL BE MORE PERSISTENT IN THE FAVORED SN
BELTS E OF MARQUETTE...BUT LO INVRN BASE BLO H85 SHOWN ON THE FCST
SDNGS UNDER THE NEGATIVE DYNAMICS WL LIMIT SN TOTALS. AS THE SFC
RDG AXIS SHIFTS TO THE E AND THE FLOW BACKS TO THE W-SW...LINGERING
LES WL SHIFT OUT INTO LK SUP ON THU NGT. TEMPS COULD FALL QUICKLY IN
THE EVNG BEFORE MORE HI CLDS ASSOCIATED WITH DVLPG ISENTROPIC ASCENT
OVERSPREAD THE AREA W-E.
FRI INTO SAT...AS THE UPR TROF IN ERN NAMERICA SHIFTS TO THE E...THE
FLOW OVER THE CONUS/SRN CANADA WL BECOME MORE ZONAL. DVLPG LLVL SW
FLOW/ISENTROPIC ASCENT OVER THE GREAT LKS ON THE NW FLANK OF SFC HI
PRES SHIFTING INTO THE SRN MID ATLANTIC STATES THAT WL BE FORCING
THIS CHANGE IN THE UPR PATTERN IS PROGGED BY MOST OF THE MEDIUM
RANGE GUIDANCE IS FCST TO BRING ABOUT SOME INCRSG MID LVL MSTR/PCPN
ON FRI TO THE NE OF AN H85 WARM FNT STRETCHING FM THE NRN PLAINS
INTO MN. THE LATEST MODEL GUIDANCE HINTS THE HEAVIER PCPN ASSOCIATED
WITH THIS WARM AIR RETURN ON FRI MAY FALL TO THE SW IN WI. EXPECT
THE HIER POPS OVER THE ERN CWA WITH SW FLOW OF COLD AIR OFF LK MI
ALLOWING FOR SOME LES INTO THAT AREA ON FRI. AS A SHRTWV WITHIN THE
ZONAL FLOW SHIFTS EWD NEAR THE CNDN BORDER...A SFC LO PRES WL SHIFT
EWD AND JUST N OF LK SUP ON SAT. MOST OF THE GUIDANCE SHOWS H85
TEMPS RISING TO AOA 0C OVER AT LEAST THE S HALF OF THE CWA ON SAT...
INDICATING THE POTENTIAL FOR SOME MIXED PCPN. GFS FCST SDNGS SHOW AN
ELEVATED WARM LYR...SO INCLUDED A MENTION OF SOME FREEZING RA OVER
THE SCENTRAL WHERE THE WARM WEDGE H85 TEMPS ARE OVER 0C. THE MODELS
SUCH AS THE 12Z GFS AND ESPECIALLY THE 12Z CND THAT SHOW THE DEEPEST
SFC LO/FARTHER N TRACK ACTUALLY INDICATE UPR MI MIGHT SEE SOME DRY
SLOTTING AS THE H85 WARM FNT SHIFTS TO THE N OF THE CWA AND H85
TEMPS RISE AS HI AS 5-6C...SO POPS WL BE LOWEST OVER THE S.
SUN/MON...AS THE SHRTWV/SFC LO SHIFT INTO QUEBEC SAT NGT/SUN...
ATTENDANT COLD FNT WL SWING THRU UPR MI AND BRING A RETURN OF COLDER
AIR AND SOME LES FOR SUN. TRAILING HI PRES WL PASS TRHU THE CENTRAL
GREAT LKS ON SUN NGT...ENDING THIS LES. AS THE HI SHIFTS TOWARD NEW
ENGLAND...EXPECT A RETURN SW FLOW OF WARMER AIR TO DVLP ON MON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 122 AM EST TUE NOV 25 2014
IFR CONDITIONS WILL CONTINUE THROUGH THE OVERNIGHT BEFORE IMPROVING
TO MVFR ON TUESDAY AS DRIER AIR MOVES IN. BY LATE AFTERNOON INTO
EARLY EVENING...VFR CONDITIONS WILL PREVAIL AT ALL SITES AS WINDS
PUSH LAKE EFFECT SNOW BANDS WELL OFFSHORE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 358 PM EST MON NOV 24 2014
STRONG LOW PRESSURE NEAR SAULT STE MARIE JUST SOUTH OF JAMES BAY
WILL RAPIDLY MOVE INTO NRN QUEBEC TONIGHT. N-NW GALES WILL PERSIST
ACROSS THE LAKE TONIGHT...THEN SUBSIDE RATHER QUICKLY TUESDAY
MORNING. GENERALLY QUIET WEATHER EXPECTED FOR THE REMAINDER OF THE
WEEK...ALTHOUGH A LOW PRESSURE SYSTEM MOVING SOUTH OF THE LAKE WED
INTO WED NIGHT MAY ALLOW FOR N-NE WINDS TO GUST TO NEAR GALE FORCE.
HIGH PRESSURE BY THE WEEKEND SHOULD ALLOW FOR WINDS LESS THAN 20 KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
MIZ006-007-085.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST /6 AM CST/ THIS MORNING
FOR MIZ001>003-009.
LAKESHORE FLOOD ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
MIZ001-003-005>007.
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ004-005.
WINTER WEATHER ADVISORY UNTIL 5 AM CST EARLY THIS MORNING FOR
MIZ012.
LAKE SUPERIOR...
GALE WARNING UNTIL 4 AM EST EARLY THIS MORNING FOR LSZ248>251-
265>267.
GALE WARNING UNTIL 2 AM EST EARLY THIS MORNING FOR LSZ242>245-
263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...MRD
LONG TERM...KC
AVIATION...07
MARINE...MRD
AREA FORECAST DISCUSSION...CORRECTED
NWS TWIN CITIES/CHANHASSEN MN
1039 PM CST MON NOV 24 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 249 PM CST MON NOV 24 2014
ISSUED BY NATIONAL WEATHER SERVICE LA CROSSE WI
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED A POTENT TROUGH COMING INTO CENTRAL BRITISH COLUMBIA ON TOP
OF EAST PACIFIC RIDGING...AND MORE TROUGHING COVERING MUCH OF
CENTRAL NORTH AMERICA. WITHIN THIS BROAD TROUGH...A SHORTWAVE WAS
PRESENT OVER EASTERN IOWA/NORTHERN IL...WHICH DPVA FROM IT COMBINED
WITH A BAND OF MID LEVEL FRONTOGENESIS HAS ALLOWED A BAND OF SNOW TO
PERSIST FROM WESTERN INTO SOUTHERN WI. ADDITIONAL SNOW SHOWERS HAVE
BEEN TAKING PLACE ACROSS MUCH OF MN INTO IA...MOSTLY ASSOCIATED WITH
INSTABILITY PRODUCED FROM COOL MID LEVEL TEMPS ALOFT AND RELATIVELY
WARMER TEMPS/DEWPOINTS AT THE SURFACE. RAP 700MB TEMPS SHOWED
READING IN THE -12 TO -13C RANGE...MEANWHILE SURFACE TEMPS HAVE
COOLED INTO THE TEENS AND 20S...WARMEST IN WESTERN WI. A TIGHT
PRESSURE GRADIENT IN PLACE...BETWEEN A SURFACE RIDGE OVER THE
WESTERN PLAINS AND A LOW PRESSURE TROUGH IN NORTHERN LOWER MI...HAS
PRODUCED GUSTS OF 30-40 MPH. THE STRONGEST GUSTS HAVE BEEN CONFINED
TO SOUTHWEST AND SOUTH CENTRAL MN WHERE THE DEEPEST MIXING HAS BEEN
TAKING PLACE. FARTHER TO THE WEST...A LARGE EXPANSE OF CLEARING
DOMINATES A LOT OF THE PLAINS...ASSOCIATED WITH THE SURFACE RIDGE
AND VERY DRY AIR. PRECIPITABLE WATER VALUES THERE ARE IN THE 0.1-0.2
INCH RANGE.
THE FOCUS FOR ATTENTION BEGINS TO SHIFT TO THAT POTENT TROUGH OVER
CENTRAL BRITISH COLUMBIA. GOOD MODEL CONSENSUS EXISTS FOR THE TROUGH
TO DIG DOWN INTO THE WESTERN DAKOTAS BY 00Z WEDNESDAY...ALLOWING
WEAK RIDGING TO BUILD OVER THE FORECAST AREA. ADDITIONALLY...THE
NEXT POTENT TROUGH WILL HELP PUSH THE CURRENT SHORTWAVE TROUGH AND
700MB COOL AIR SITUATED OVER THE FORECAST AREA OFF TO THE EAST.
FOR TONIGHT...ANTICIPATING SNOW SHOWERS OVER MINNESOTA TO DIMINISH
QUICKLY THIS EVENING WITH LOSS OF DAYTIME HEATING. FIGURE
SOMEWHERE AROUND 03Z THEY SHOULD HAVE ENDED...IN AGREEMENT WITH A
LOT OF HI RESOLUTION MODEL GUIDANCE. THE SNOW OVER WESTERN WI WILL
TAKE LONGER TO END BEING ASSOCIATED WITH THE MID LEVEL
FRONTOGENESIS BAND THERE...SOMEWHERE AROUND 06Z. CURRENT WINTER
WEATHER ADVISORY END TIME STILL LOOKS GOOD. REGARDING THE WIND
ADVISORY...PRESENT WINDS ARE MARGINAL TO KEEP IT GOING.
HOWEVER...SINCE CONDITIONS REMAIN BRISK FOR THE REST OF THE
AFTERNOON AND WINDS ARE STILL ON TRACK TO DIMINISH THIS
EVENING...PLAN ON LETTING THE WIND ADVISORY EXPIRE AT 6 PM. CLEARING
ACROSS THE PLAINS SHOULD MAKE ITS WAY WEST TO EAST ACROSS A LOT OF
THE FORECAST AREA...PERHAPS EVEN INTO WESTERN WI BY 12Z. THE
CLEARING COMBINED WITH A WEAKENING PRESSURE GRADIENT AND ALREADY
COOL TEMPERATURES SHOULD ALLOW READINGS TO DIP INTO THE SINGLE
DIGITS OVER WEST-CENTRAL MN. TEENS ARE LIKELY ELSEWHERE WITH MORE
CLOUDS AND WIND. IT SHOULD BE NOTED THAT MORE CLOUDS ARE LIKELY TO
COME INTO WESTERN SECTIONS OF THE FORECAST AREA BY 12Z...AHEAD OF
THE APPROACHING POTENT TROUGH.
ON TUESDAY...CLOUDS WILL MARCH THEIR WAY WEST TO EAST ACROSS THE
FORECAST AREA AGAIN AS THE POTENT TROUGH MOVES INTO THE WESTERN
DAKOTAS. ANY PRECIPITATION DOES LOOK TO REMAIN TO THE WEST PRIOR TO
00Z WEDNESDAY...THOUGH. ALTHOUGH THERE MIGHT BE MORE CLOUDS...
INCREASING SOUTHWESTERLY FLOW AHEAD OF THE AFTERNOON SHOULD HELP
GIVE TEMPERATURES A BOOST. IN FACT...925MB READINGS CLIMB FROM
AROUND -10C AT 12Z TO -4 TO -7C BY 00Z...WARMEST NEAR MANKATO AND
NEW ULM. MOST LOCATIONS SHOULD SEE HIGHS IN THE 20S...WITH 30S
POSSIBLE NEAR THE MN RIVER.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 249 PM CST MON NOV 24 2014
ISSUED BY NATIONAL WEATHER SERVICE LA CROSSE WI
MAIN FOCUS STARTING OFF THE PERIOD IS THE POTENT SHORTWAVE TROUGH
CURRENTLY IN CENTRAL BRITISH COLUMBIA. THERE HAS BEEN A MAJOR TREND
OVER THE PAST 2 DAYS TO DIG THIS TROUGH FARTHER SOUTHWEST...
ESPECIALLY IN THE ECMWF. THIS TREND APPEARS TO BE RELATED TO THE
CURRENT CENTRAL NORTH AMERICA TROUGH BEING MORE AMPLIFIED THAN
PREVIOUSLY PROGGED. AS A RESULT OF THIS TREND...THERE IS A CHANCE
SUGGESTED BY THE 24.12Z GFS THAT MUCH OF THE AREA COULD BE MISSED BY
THIS SYSTEM. THIS WOULD BE GOOD NEWS FOR TRAVELERS. IN THE GFS...THE
SHORTWAVE TROUGH AND ITS ASSOCIATED SURFACE LOW DIVE DOWN TO NEAR
THE KANSAS CITY AREA BY 12Z...WITH THE ISENTROPIC LIFT/MID LEVEL
FRONTOGENESIS ZONE BRUSHING THE MN RIVER VALLEY WITH SOME SNOW
BETWEEN 06-18Z WEDNESDAY. HAVE TRENDED THE FORECAST DRIER TO ACCOUNT
FOR THE MODEL TREND...BUT QPF AND POPS MAY NEED TO BE REDUCED
FURTHER. TEMPERATURES SHOULD NOT DROP MUCH TUESDAY NIGHT WITH THE
CLOUDS IN PLACE AND EVEN SOME SLIGHT WARM ADVECTION POSSIBLE. FOR
WEDNESDAY...HIGHS ARE LIKELY TO OCCUR BY NOON AS COLD ADVECTION
LOOKS TO COMMENCE IN THE WAKE OF THE TROUGH. THE AMOUNT OF ADVECTION
DEPENDS ON HOW FAR SOUTH THE TROUGH DIGS...THUS THESE READINGS ARE
SUBJECT TO CHANGE.
DRY AND COLDER CONDITIONS REMAIN PROGGED TO AFFECT THE AREA FOR
WEDNESDAY NIGHT AND THANKSGIVING...AS ARCTIC HIGH PRESSURE MOVES IN
FROM THE NORTHWEST. 925MB TEMPS TOPPING OUT IN THE -10 TO -16C RANGE
WILL ONLY ALLOW FOR HIGHS IN THE TEENS.
A PATTERN CHANGE IS IN THE OFFERING FOR THURSDAY NIGHT INTO EARLY
NEXT WEEK WITH MODELS ADVERTISING A SERIES OF TROUGHS MOVING INTO
THE WESTERN U.S.. THIS RESULTS IN A MORE ZONAL FLOW PATTERN
DOWNSTREAM TO EVENTUALLY SOUTHWESTERLY EARLY NEXT WEEK. THE SWITCH
TO ZONAL FLOW RESULTS IN A WARM ADVECTION REGIME THURSDAY NIGHT AND
FRIDAY. ON THE NOSE OF THE WARM ADVECTION...A MID-LEVEL
FRONTOGENESIS SNOWFALL BAND LOOKS TO SETUP FROM THE DAKOTAS THROUGH
MINNESOTA AND WISCONSIN. EXACT PLACEMENT AND AMOUNTS ARE YET TO BE
DETERMINED...BUT THE FOCUS RIGHT NOW GENERALLY APPEARS ALONG/NORTH
OF I-94. THE WARM FRONT LOOKS TO LIFT THROUGH MUCH OF THE FORECAST
AREA FRIDAY NIGHT. THEN FOR SATURDAY...A SHORTWAVE CROSSES THE AREA
IN THE ZONAL FLOW...SENDING A COLD FRONT THROUGH. THIS PERIOD COULD
BE TRICKY FOR HIGHS. IF THE FRONT IS SLOWER...HIGHS COULD EASILY TOP
OUT IN THE 40S. HOWEVER...AT THE CURRENT SPEED...UPPER 20S TO MID
30S SEEM MORE REASONABLE. DESPITE THE ZONAL FLOW...AN ARCTIC LOW
LEVEL INTRUSION LOOKS TO AFFECT THE AREA FOR SATURDAY NIGHT AND
SUNDAY...ACCOMPANIED BY ARCTIC HIGH PRESSURE...NOTED BY 925MB TEMPS
ABOUT 5C COLDER THAN AT 850MB. THOSE 925MB TEMPS ON SUNDAY RANGING
FROM -10 TO -15C MEANS BACK TO HIGHS IN THE TEENS. WE SHOULD BEGIN
TO DISLODGE THE COLD AIR ON MONDAY WITH THE UPPER FLOW TURNING
SOUTHWESTERLY...ALLOWING FOR A REBOUND BACK INTO THE 20S FOR HIGHS.
CONDITIONS LOOK TO REMAIN DRY FOR MONDAY WITH ARCTIC HIGH PRESSURE
IN PLACE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 1039 PM CST MON NOV 24 2014
MVFR CIGS ARE IN PLACE OVER FAR EASTERN MINNESOTA AND WISCONSIN...
BUT CLEARING IS PUSHING EASTWARD INTO WESTERN MINNESOTA. THIS TREND
WILL CONTINUE THROUGH THE NIGHT WITH VFR CONDITIONS GRADUALLY
RETURNING. THE STEADY SNOW HAS ENDED...BUT A FEW FLURRIES CANNOT BE
RULED OUT ACROSS WI. SOME MVFR CIGS COULD RETURN LATE SATURDAY AS
ANOTHER SYSTEM APPROACHES. WINDS WILL EASE THIS EVENING AND BECOME
LIGHT/VARIABLE TUESDAY AFTERNOON.
KMSP...MAINLY VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. SOME
HIGH/MID LEVEL CLOUDS MAY STICK AROUND TUESDAY MORNING BEFORE LOWER
MVFR CLOUDS RETURN LATE TUESDAY.
/OUTLOOK FOR KMSP/
WED...MVFR/IFR CHC -SN EARLY. WINDS NW 10-15KTS.
THU...VFR. WINDS LIGHT/VARIABLE.
FRI...VFR/CHC MVFR AND -SN. WINDS S 5 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
557 PM CST WED NOV 26 2014
.SYNOPSIS...
ISSUED AT 318 PM CST WED NOV 26 2014
H5 ANALYSIS FROM THIS MORNING HAS A CLOSED LOW OVER
NUNAVUT WITH A TROUGH EXTENDING SWD INTO THE SERN CONUS. A COUPLE OF
UPPER LEVEL DISTURBANCES WERE NOTED OVER KENTUCKY AND NRN MO. STRONG
WINDS WERE NOTED IN THE MID LEVELS AS A 90+KT H5 JET STREAK EXTENDED
FROM WESTERN MT INTO SWRN KS. AT THE SURFACE...LOW PRESSURE WAS
PRESENT OVER NRN MO WITH A COLD FRONT EXTENDING SOUTH AND WEST OF
THE LOW INTO THE OZARKS AND TX PANHANDLE. COLD AIR BEHIND THE FRONT
HAS BACKED TO ALONG THE FRONT RANGES OF THE ROCKIES IN COLORADO AND
WYOMING. LOOKING AT THE H7 THERMAL FIELD...A DECENT FRONTAL BOUNDARY
EXTENDED ACROSS THE PANHANDLE AND EXTREME SOUTHWESTERN NEBRASKA. THE
H7 FRONT...COUPLED WITH THE H5 JET STREAK...HAS LED TO LIGHT SNOW
ACROSS THE PANHANDLE AND NORTHEASTERN COLORADO THIS AFTERNOON. SKIES
WERE MOSTLY CLOUDY ACROSS WESTERN AND NORTH CENTRAL NEBRASKA THIS
AFTERNOON. TEMPERATURES AS OF MID AFTERNOON RANGED FROM 25 AT ONEILL
TO 34 AT NORTH PLATTE AND OGALLALA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 318 PM CST WED NOV 26 2014
LOW TO MID LEVEL FRONTOGENETIC BAND CURRENTLY
ACROSS SOUTHWEST NEBRASKA IS SHOWN BY THE HIRES NEAR TERM MODELS TO
BECOME LESS DEFINED THROUGH THE AFTERNOON AS THE ATMOSPHERE LOSES
SATURATION IN THE DENDRITIC GROWTH ZONE. THE HRRR SEEMS TO BE
HANDLING THE CURRENT SITUATION WELL...THUS THE FORECAST WAS TRENDED
IN THAT DIRECTION WITH SNOW ENDING ACROSS OUR SOUTHWEST THIS
EVENING. THE LATEST HRRR DOES SHOW ANOTHER PUSH OF LOWER LEVEL
MOISTURE THIS EVENING...THUS THE REASON OF EXTENDING A SNOW MENTION
INTO THIS EVENING. ACROSS NORTH CENTRAL NEBRASKA THIS
EVENING...BUFR SOUNDINGS SHOW DEEP SATURATION...WHICH AT TIMES
REACHES INTO THE DGZ...WHATS MISSING IS DEEP LIFT...BUT THERE ARE
INDICATIONS OF AT LEAST WEAK OMEGA. PREVIOUS FORECAST HANDLED THIS
POTENTIAL WITH --SN...WILL DO THE SAME.
OVERNIGHT LOWS WILL BE CHILLY...WITH LESS MIXING IN MIND OVERNIGHT
LOWS SHOULD BOTTOM OUT IN THE TEENS ACROSS THE EAST...WITH LOWER 20S
OVER THE HIGHER TERRAIN OF THE WEST.
TOMORROW...A GENERAL WARMING AND DRYING TREND IS FORECAST BY ALL
AVAILABLE GUIDANCE AS SFC HIGH PRESSURE BUILDS OFF TO THE EAST AND A
LEE TROUGH DEEPENS TO THE WEST. SOUTHERLY...TO WESTERLY FLOW WILL
ADVECT WARMER H85 TEMPS ACROSS THE REGION...WITH OUR FAR WESTERN &
SOUTHWESTERN ZONES TOPPING 10C BY 00Z FRIDAY. THIS SHOULD PROVIDE
FOR TEMPERATURES IN THE LOWER 60S ACROSS SOUTHWEST NEBRASKA AND THE
EASTERN PANHANDLE. THERE WILL REMAIN A SHARP GRADIENT OF
TEMPERATURES AS ONE HEADS EAST. ACROSS THE HEART OF THE SANDHILLS
HIGHS IN THE 40S AND 50S SHOULD PREVAIL...TO THE EAST OF
THERE...ACROSS NORTH CENTRAL NEBRASKA...HIGHS MAY STRUGGLE TO REACH
INTO THE MID 30S...OWING THE PRESENCE OF PERSISTENT STRATUS AND
COOLER AIR RECYCLED FROM THE DEPARTING HIGH. YOUR THANKSGIVING
FORECAST IS DRY AS THE TROPOSPHERIC COLUMN IS SHOWN TO DRY ON
THURSDAY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 318 PM CST WED NOV 26 2014
MID RANGE...THURSDAY NIGHT THROUGH SATURDAY...IN THE
MID RANGE...UNSEASONABLY WARM AND DRY CONDITIONS ARE
EXPECTED...WITH THE MAIN FORECAST CHALLENGE BEING HIGH TEMPERATURES
FOR FRIDAY AND SATURDAY. FOR THURSDAY NIGHT...A WARM FRONT WILL
CONTINUE TO LIFT NORTHEAST OF THE AREA INTO NORTH DAKOTA AND
MINNESOTA. A WEAK SURFACE TROUGH OF LOW PRESSURE WILL DEVELOP ACROSS
THE HIGH PLAINS OF NEBRASKA AND KANSAS OVERNIGHT LEADING TO LIGHT
WESTERLY WINDS. OVERNIGHT LOWS WILL BE ON THE MILD SIDE FOR THIS TIME OF
YEAR WITH READINGS AROUND 25 FORECAST FOR FRIDAY MORNING. WITH LIGHT
WESTERLY WINDS FORECAST...WENT WITH SOME LOWER 20S IN THE PLATTE
RIVER VALLEY. FRIDAY AND FRIDAY NIGHT...WARM H85 TEMPS WILL PUSH
INTO THE REGION WITH H85 TEMPS RANGING FROM 8 TO 16C. THIS WILL
RESULT IN HIGHS WELL INTO THE 50S TO MIDDLE 60S FRIDAY AFTERNOON. ON
FRIDAY NIGHT...LOWS WILL BE MILD WITH TEMPERATURES IN THE UPPER 20S
TO LOWER 30S EXPECTED. ON SATURDAY...AN ARCTIC COLD FRONT WILL PUSH
INTO THE DAKOTAS...ENDING UP SOMEWHERE IN SOUTH DAKOTA BY 00Z
SUNDAY. THE EURO SOLN IS MOST AGGRESSIVE WITH THE FRONT BEING ALONG
THE SD/NE BORDER BY THIS TIME. THE NAM AND GFS ARE SLOWER AND HAVE
THE FRONT OVER CENTRAL AND NORTHERN SD DURING 00Z SUNDAY.
REGARDLESS...THE FRONT WILL BE NORTH OF THE FORECAST AREA BEFORE
PEAK HEATING. WITH THE APPG FRONT AND H85 TEMPS REACHING THE MIDDLE
TO UPPER TEENS SAT AFTN...HIGHS WILL SURGE INTO THE 60S AND MAY
APPROACH 70 IN THE SOUTHWEST. RECORDS FOR SATURDAY ARE IN THE MID
70S FOR VALENTINE AND IMPERIAL...AND 71 FOR NORTH PLATTE AND 69 FOR
BROKEN BOW RESPECTIVELY.
LONG RANGE...SATURDAY NIGHT THROUGH WEDNESDAY...A STRONG ARCTIC
FROPA WILL PUSH THROUGH THE FORECAST AREA SATURDAY NIGHT. FORECAST
WILL CONTINUE TO BE DRY BEHIND THE FRONT WITH THE BEST FORCING OVER
NORTH DAKOTA AND NRN MINNESOTA. H85 TEMPS BEHIND THE FRONT SUNDAY
WILL RANGE FROM -13C IN THE NORTH TO -7C IN THE SOUTH. WITH DECENT
NORTHERLY WINDS AND MIXING HIGHS WILL STRUGGLE TO GET OUT OF THE 20S
SUNDAY. TEMPERATURES WILL MODERATE SOME MONDAY...WITH A BETTER
WARMUP EXPECTED ON TUESDAY AND WEDNESDAY. BY WEDNESDAY...THE
PRECIPITATION FORECAST BECOMES MORE OF A CHALLENGE THANKS TO SPLIT
FLOW. THE LATEST GFS AND ECMWF HAVE DIVERGENT SOLUTIONS TOWARD THE
MIDDLE OF THE WEEK. THE GFS IS MOST AGGRESSIVE...PUSHING A SHORTWAVE
TROUGH ACROSS THE INTERMOUNTAIN WEST WEDNESDAY...WHILE THE ECMWF HAS
THE TROUGH IN NRN CALIFORNIA. WITH THE MODEL DISAGREEMENTS
ATTM...WILL LEAVE THE PERIOD DRY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 555 PM CST WED NOV 26 2014
THE CONCERN TO AVIATION WITH THIS FORECAST PACKAGE IS THE
SCATTERED SNOW SHOWERS IN WESTERN AND SOUTHWEST NEBRASKA. CEILING
WITH THE SNOW IS EXPECTED TO BE 1000-3000 FEET AGL WITH VISIBILITY
POSSIBLE AS LOW AS 1SM BUT GENERALLY 3-5SM. THE SNOW IN THOSE
AREAS WILL DISSIPATE BY 08Z WITH IMPROVED CEILING AND VISIBILITY
FLOOLOWING. THE SNOW IS NOT LIKELY TO HAVE SIGNIFICANT IMPACT ON
FLIGHT CEILING OR VISIBILITY AT VTN OR LBF. CEILINGS SOUTH AND
WEST OF KIEN-LXN WILL BE 7000-12000 FEET WITH VISIBILITY AT OR
ABOVE 6SM. IN THE REST OF THE AREA...UNLIMITED CEILING AND
VISIBILITY WILL BE THE RULE THROUGH THURSDAY EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...JACOBS
LONG TERM...CLB
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1149 AM CST TUE NOV 25 2014
.UPDATE...
ISSUED AT 545 AM CST TUE NOV 25 2014
FURTHER MONITORING OF SATELLITE TRENDS NECESSITATES INCREASING
CLOUD COVER FASTER THAN IN THE 3 AM FCST ISSUANCE. THERE IS A LOT
OF THICK CIRROSTRATUS/ALTOSTRATUS/ALTOCU UPSTREAM AND IT IS NOT
SHOWING ANY SIGNS OF THINNING. SO SKY COVER WAS INCREASED FURTHER.
BASED ON THIS...HIGH TEMPS WERE ALSO LOWERED 2-4F AND THAT MAY NOT
BE ENOUGH GIVEN HOW COLD TEMPS ARE RIGHT NOW. WHILE WAA WILL BE IN
PROGRESS...IT`S ALWAYS HARD TO FIGHT THE EFFECTS OF THICK CLOUD
COVER. WE NOW HAVE 43-50F WITH MID 40S IN THE TRI-CITIES VS.
45-53F WITH UPR 40S IN THE TRI-CITIES.
THE CANADIAN GEM DOES WELL IN THESE "SURPRISE" TEMP REGIMES AND IT
MAY WELL BE ONTO THIS. IT HAS 40-47F WITH 42-44F TRI-CITIES.
SUFFICE TO SAY FURTHER DOWNWARD REFINEMENTS MAY BE FORTHCOMING BY
THE DAY SHIFT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 545 AM CST TUE NOV 25 2014
...BECOMING CLOUDY WITH ANOTHER LIGHT PRECIP EVENT LATE THIS
AFTERNOON/EVE FOLLOWED BY MORE WIND...
ALOFT: THE FLOW WAS HIGHLY AMPLIFIED WITH A LONGWAVE TROF OVER
THE CNTRL USA AND RIDGES JUST OFF BOTH COASTS. WV IMAGERY SHOWED A
SHORTWAVE TROF OVER ALBERTA. THIS TROF WILL DIVE SE INTO THE
DAKOTAS TODAY AND INTO NEB/KS TONIGHT...DEEPENING OVER TIME WITH A
GOOD SHOT OF QG FORCING IN THE EXIT REGION OF A 150 KT UPR-LVL JET.
SURFACE: A CLIPPER LOW WAS ORGANIZING OVER ALBERTA. THIS LOW WILL
RACE INTO THE DAKOTAS TODAY AND BE LOCATED OVER WRN IA BY DAYBREAK
WED. ITS COLD FRONT WILL SWEEP THRU TONIGHT.
TODAY: WAA WILL CONT IN THE WARM SECTOR OF THE CLIPPER. MORNING
SUN WILL RAPIDLY BE OBSCURED BY INCREASING AND DESCENDING MID-HIGH
CLOUDS. ONE WEAKNESS IN THIS FCST IS THAT CLOUDS MAY COME IN THICK
FASTER THAN CURRENTLY DEPICTED. I.E. WE MAY NOT BE PESSIMISTIC
ENOUGH. THAT IS A DENSE CIRRUS SHIELD ON SATELLITE IMAGERY.
MODEL CONSENSUS INCLUDING HI-RES MODELING INDICATE A SWATH OF
FGEN-ENHANCED LIGHT RAIN AND/OR SPRINKLES WILL DEVELOP AND CROSS
THE FCST AREA FROM 3PM-12AM. SPRINKLES ARE MOST LIKELY ON THE SRN
FRINGE OF THE PRECIP SHIELD. INCLUDED SPRINKLES S AND W OF THE
MODEL CONSENSUS OF .01" QPF AS SOME SREF MEMBERS DO HINT AT THE
POSSIBILITY OF RAIN OUTSIDE OF THE BEST MODEL CLUSTERING.
USED THE 05Z BIAS CORRECTED RAP FOR HIGHS TODAY WHICH SEEMS TO
HAVE A BETTER GRASP ON WHERE THICKER CLOUDS WILL ARRIVE FROM THE
N. DESPITE THE CLOUDS SHOULD BE A MILD DAY WITH TEMPS AT OR
SLIGHTLY ABOVE NORMAL.
THERE IS CONSIDERABLE UNCERTAINTY IN DWPTS/RH TODAY WITH 10F OF
SPREAD BETWEEN THE MAV/MET MOS. USED CONSENSUS OF SHORT-TERM HI-
RES MODELS WHICH WERE NOT THE LOWEST BUT DID FAVOR THE DRIER MAV
MOS. THIS WILL WORK BEST OUTSIDE WHERE IT RAINS...BUT MOISTENING
FROM RAINFALL WILL INCREASE DWPTS LOCALLY.
TONIGHT: SWATH OF RAIN/SPRINKLES EXITS TO THE E BY MIDNIGHT.
STRONG CAA KICKS IN AFTER PASSAGE OF THE COLD FRONT WITH A CORE OF
50 KT WINDS AT 850 MB. OUTPUT FROM THE WIND GUST TOOL SEEMED TOO
LOW SO USED GUSTS FROM A BLEND OF THE 18Z/00Z RAW MODEL GUIDANCE
/CONSRAW/. NW WINDS WILL GUST 30-35 KTS N OF HWY 6 BEGINNING 3 AM.
WITH 40 KTS AS LOW AS 1500 FT...CAN`T RULE OUT ISOLATED HIGHER
GUSTS.
P-TYPE: KEPT IT PRIMARILY RAIN/SPRINKLES EXCEPT ON THE EXTREME
NE/E FRINGES OF THE FCST AREA 07Z-08Z ON THE BACK EDGE OF THE
PRECIP...IF IT`S STILL FALLING BY THEN. NAM P-TYPE ALGORITHM KEEPS
IT ALL RAIN AND FCST SOUNDINGS SUGGEST THE LEFTOVER DAYTIME BL
WILL BE TOO WARM TO SUPPORT SNOW. EVEN WETBULB TEMPS FAVOR RAIN
WITH +2 UP TO 1K FT. CURRENT INDICATIONS ARE THAT THE PRECIP
SHOULD BE OVER BY THE TIME TEMP PROFILES COOL ENOUGH FOR SNOW.
MODEL 2M TEMPS SUGGEST A FAIRLY MILD NIGHT WITH LOWS 27-38F AND
30-31F IN THE TRI-CITIES. EVEN THE MOS 3-HOURLY TEMPS SUGGEST
THIS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 308 AM CST TUE NOV 25 2014
WE ARE CALLING FOR A DRY FORECAST FROM START TO FINISH THIS
HOLIDAY WEEKEND. THE PRIMARY FORECAST CONCERN WILL CENTER AROUND
SEVERAL BIG TEMPERATURE SWINGS. EXPECT TWO COLD AIR OUTBREAKS...
ONE ON WEDNESDAY LASTING INTO THANKSGIVING DAY...AND A SECOND SHOT
OF COLD AIR TO FINISH THE HOLIDAY WEEKEND ON SUNDAY. HOWEVER...
FRIDAY AND SATURDAY CURRENTLY APPEAR TO BE WARM WITH HIGHS WELL
ABOVE NORMAL.
WEDNESDAY...A COLD FRONTAL PASSAGE LATE TUESDAY NIGHT WILL ALLOW
COOLER AIR TO FILTER INTO OUR REGION THROUGHOUT THE DAY. THEREFORE
...TEMPERATURES WILL WARM VERY LITTLE IF AT ALL DURING THE DAYTIME
HOURS. WE CAN NOT RULE OUT A FLURRY OR TWO WITH A LITTLE 850/700
MB MOISTURE AND COOLER AIR SETTLING IN. HOWEVER...FORECAST MODELS
CONTINUE TO BE IN GOOD AGREEMENT IN 0.00 QPF AND THE CHANCE OF
FLURRIES IS STILL TOO LOW TO INCLUDE MENTION IN THE FORECAST.
THERE COULD BE A PRETTY GOOD TEMPERATURE CONTRAST ACROSS THE
FORECAST AREA AS THE COLD AIR WILL HANG UP MORE OVER NEBRASKA.
THEREFORE...EXPECT HIGHS ON WEDNESDAY SHOULD RANGE FROM THE 30S
ACROSS SOUTH CENTRAL NEBRASKA TO THE LOWER 40S OVER NORTH CENTRAL
KANSAS.
THANKSGIVING...FORECAST MODELS ARE IN INCREASINGLY GOOD AGREEMENT
THAT WE WILL SLOWLY START TO WARM BACK UP ON THANKSGIVING DAY. AN
UPPER RIDGE WILL BEGIN TO WORK ITS WAY EAST INTO THE FORECAST AREA
BRINGING WARMER AIR ALOFT. AT THE SFC...THE WIND WILL TURN TO
SOUTHERLY AND WILL ALSO RESULT IN WARM AIR ADVECTION. THE WARMING
WILL BE GRADUAL ON THANKSGIVING WITH ONLY A FEW DEGREE RISE
EXPECTED OVER WEDNESDAY HIGHS...BUT THE WARM UP WILL INCREASE AS
WE HEAD INTO FRIDAY. AS FOR THANKSGIVING...EXPECT HIGHS IN THE
UPPER 30S NORTHEASTERN ZONES...TO AROUND 40 IN THE TRI-CITIES...TO
THE MID AND UPPER 40S OVER NORTH CENTRAL KANSAS.
FRIDAY AND SATURDAY...THE OVERALL UPPER FLOW BECOMES MORE ZONAL
WITH THE REAL COLD AIR BOXED UP IN PORTIONS OF THE DAKOTAS AND IN
CANADA. THIS WILL ALSO KEEP THE STORM TRACK WELL TO OUR NORTH
RESULTING IN CONTINUED DRY CONDITIONS. THERE IS HIGH CONFIDENCE IN
FRIDAY BEING A VERY NICE DAY WITH WARM AIR ADVECTION BOTH ALOFT
AND AT THE SFC. THE SFC WINDS WILL BE FAIRLY LIGHT BUT SHOULD HAVE
A BIT OF A DOWNSLOPE WARMING COMPONENT TO IT BEING OUT OF THE WEST
TO SOUTHWEST. ALL IN ALL EXPECT A VERY NICE DAY WITH HIGHS IN THE
MID TO UPPER 50S IN THE TRI-CITIES TO THE LOWER 60S OVER PORTIONS
OF NORTH CENTRAL KANSAS. FORECAST MODELS ARE COMING INTO BETTER
AGREEMENT WITH THE COLD FRONTAL PASSAGE TIMING ON SATURDAY.
OVERALL FORECAST MODELS HAVE LARGELY SLOWED DOWN THE COLD FRONT
AND BRING IT THROUGH OUR FORECAST AREA SATURDAY EVENING OR
SATURDAY NIGHT. THIS WILL ALLOW FOR FULL DIURNAL HEATING UNDER A
CONTINUED WARM AIR MASS WHICH SHOULD HELP ALL AREAS GET INTO THE
UPPER 50S TO LOWER 60S. THE 00Z ECMWF EVEN INDICATES A FEW SPOTS
COULD HIT 70 SATURDAY AFTERNOON. EVERYTHING HINGES ON THE TIMING
OF THE COLD FRONT...BUT RIGHT NOW SATURDAY APPEARS TO BE A GREAT
DAY TO GET OUT AND ENJOY BEFORE THE NEXT COLD SNAP HITS.
SUNDAY AND MONDAY...THERE IS CURRENTLY DECENT FORECAST AGREEMENT
BETWEEN THE 00Z GFS AND 00Z ECMWF THAT A PRETTY POTENT COLD AIR
MASS WILL OVERSPREAD THE AREA SATURDAY NIGHT INTO SUNDAY. IT
SHOULD BE A DRY FRONTAL PASSAGE SO WE ARE NOT REALLY WORRIED ABOUT
SNOW...BUT IT DOES APPEAR TO BE COLD. OUR FORECAST HIGHS BASED OFF
THE SUPERBLEND OF MODELS RANGE FROM THE UPPER 20S IN ORD TO THE
30S ELSEWHERE AND THIS MAY BE OPTIMISTICALLY TOO WARM IF YOU
BELIEVE THE DETERMINISTIC 00Z GFS AND ECMWF MODEL RUNS. THERE IS A
HIGH LEVEL OF UNCERTAINTY AS TOO HOW LONG THE COLD AIR WILL LINGER
ACROSS THE AREA AS THE 00Z GFS IS MUCH QUICKER TO PUSH THE COLD
AIR OUT ON MONDAY THAN THE 00Z ECMWF.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1135 AM CST TUE NOV 25 2014
THE WEATHER WILL UNDERGO CHANGES DURING THE TAF PERIOD WITH A
PASSAGE OF A COLD FRONTAL BOUNDARY AND AN UPPER LEVEL DISTURBANCE.
CLOUD COVER WILL INCREASE AND THICKEN TODAY/TONIGHT AND CHCS FOR
RAIN SHOWERS INCREASE FOR THE EVENING HOURS. NW WINDS INCREASE AND
WILL BE STRONG/GUSTY BEHIND THE COLD FRONT WITH GUSTS OVER 30KT
EXPECTED. THE STRONG WINDS WILL INCREASE DURING THE OVERNIGHT
HOURS AND REMAIN STRONG/GUSTY ON WEDNESDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...HALBLAUB
LONG TERM...WESELY
AVIATION...FAY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
545 AM CST TUE NOV 25 2014
.UPDATE...
ISSUED AT 545 AM CST TUE NOV 25 2014
FURTHER MONITORING OF SATELLITE TRENDS NECESSITATES INCREASING
CLOUD COVER FASTER THAN IN THE 3 AM FCST ISSUANCE. THERE IS A LOT
OF THICK CIRROSTRATUS/ALTOSTRATUS/ALTOCU UPSTREAM AND IT IS NOT
SHOWING ANY SIGNS OF THINNING. SO SKY COVER WAS INCREASED FURTHER.
BASED ON THIS...HIGH TEMPS WERE ALSO LOWERED 2-4F AND THAT MAY NOT
BE ENOUGH GIVEN HOW COLD TEMPS ARE RIGHT NOW. WHILE WAA WILL BE IN
PROGRESS...IT`S ALWAYS HARD TO FIGHT THE EFFECTS OF THICK CLOUD
COVER. WE NOW HAVE 43-50F WITH MID 40S IN THE TRI-CITIES VS.
45-53F WITH UPR 40S IN THE TRI-CITIES.
THE CANADIAN GEM DOES WELL IN THESE "SURPRISE" TEMP REGIMES AND IT
MAY WELL BE ONTO THIS. IT HAS 40-47F WITH 42-44F TRI-CITIES.
SUFFICE TO SAY FURTHER DOWNWARD REFINEMENTS MAY BE FORTHCOMING BY
THE DAY SHIFT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 545 AM CST TUE NOV 25 2014
...BECOMING CLOUDY WITH ANOTHER LIGHT PRECIP EVENT LATE THIS
AFTERNOON/EVE FOLLOWED BY MORE WIND...
ALOFT: THE FLOW WAS HIGHLY AMPLIFIED WITH A LONGWAVE TROF OVER
THE CNTRL USA AND RIDGES JUST OFF BOTH COASTS. WV IMAGERY SHOWED A
SHORTWAVE TROF OVER ALBERTA. THIS TROF WILL DIVE SE INTO THE
DAKOTAS TODAY AND INTO NEB/KS TONIGHT...DEEPENING OVER TIME WITH A
GOOD SHOT OF QG FORCING IN THE EXIT REGION OF A 150 KT UPR-LVL JET.
SURFACE: A CLIPPER LOW WAS ORGANIZING OVER ALBERTA. THIS LOW WILL
RACE INTO THE DAKOTAS TODAY AND BE LOCATED OVER WRN IA BY DAYBREAK
WED. ITS COLD FRONT WILL SWEEP THRU TONIGHT.
TODAY: WAA WILL CONT IN THE WARM SECTOR OF THE CLIPPER. MORNING
SUN WILL RAPIDLY BE OBSCURED BY INCREASING AND DESCENDING MID-HIGH
CLOUDS. ONE WEAKNESS IN THIS FCST IS THAT CLOUDS MAY COME IN THICK
FASTER THAN CURRENTLY DEPICTED. I.E. WE MAY NOT BE PESSIMISTIC
ENOUGH. THAT IS A DENSE CIRRUS SHIELD ON SATELLITE IMAGERY.
MODEL CONSENSUS INCLUDING HI-RES MODELING INDICATE A SWATH OF
FGEN-ENHANCED LIGHT RAIN AND/OR SPRINKLES WILL DEVELOP AND CROSS
THE FCST AREA FROM 3PM-12AM. SPRINKLES ARE MOST LIKELY ON THE SRN
FRINGE OF THE PRECIP SHIELD. INCLUDED SPRINKLES S AND W OF THE
MODEL CONSENSUS OF .01" QPF AS SOME SREF MEMBERS DO HINT AT THE
POSSIBILITY OF RAIN OUTSIDE OF THE BEST MODEL CLUSTERING.
USED THE 05Z BIAS CORRECTED RAP FOR HIGHS TODAY WHICH SEEMS TO
HAVE A BETTER GRASP ON WHERE THICKER CLOUDS WILL ARRIVE FROM THE
N. DESPITE THE CLOUDS SHOULD BE A MILD DAY WITH TEMPS AT OR
SLIGHTLY ABOVE NORMAL.
THERE IS CONSIDERABLE UNCERTAINTY IN DWPTS/RH TODAY WITH 10F OF
SPREAD BETWEEN THE MAV/MET MOS. USED CONSENSUS OF SHORT-TERM HI-
RES MODELS WHICH WERE NOT THE LOWEST BUT DID FAVOR THE DRIER MAV
MOS. THIS WILL WORK BEST OUTSIDE WHERE IT RAINS...BUT MOISTENING
FROM RAINFALL WILL INCREASE DWPTS LOCALLY.
TONIGHT: SWATH OF RAIN/SPRINKLES EXITS TO THE E BY MIDNIGHT.
STRONG CAA KICKS IN AFTER PASSAGE OF THE COLD FRONT WITH A CORE OF
50 KT WINDS AT 850 MB. OUTPUT FROM THE WIND GUST TOOL SEEMED TOO
LOW SO USED GUSTS FROM A BLEND OF THE 18Z/00Z RAW MODEL GUIDANCE
/CONSRAW/. NW WINDS WILL GUST 30-35 KTS N OF HWY 6 BEGINNING 3 AM.
WITH 40 KTS AS LOW AS 1500 FT...CAN`T RULE OUT ISOLATED HIGHER
GUSTS.
P-TYPE: KEPT IT PRIMARILY RAIN/SPRINKLES EXCEPT ON THE EXTREME
NE/E FRINGES OF THE FCST AREA 07Z-08Z ON THE BACK EDGE OF THE
PRECIP...IF IT`S STILL FALLING BY THEN. NAM P-TYPE ALGORITHM KEEPS
IT ALL RAIN AND FCST SOUNDINGS SUGGEST THE LEFTOVER DAYTIME BL
WILL BE TOO WARM TO SUPPORT SNOW. EVEN WETBULB TEMPS FAVOR RAIN
WITH +2 UP TO 1K FT. CURRENT INDICATIONS ARE THAT THE PRECIP
SHOULD BE OVER BY THE TIME TEMP PROFILES COOL ENOUGH FOR SNOW.
MODEL 2M TEMPS SUGGEST A FAIRLY MILD NIGHT WITH LOWS 27-38F AND
30-31F IN THE TRI-CITIES. EVEN THE MOS 3-HOURLY TEMPS SUGGEST
THIS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 308 AM CST TUE NOV 25 2014
WE ARE CALLING FOR A DRY FORECAST FROM START TO FINISH THIS
HOLIDAY WEEKEND. THE PRIMARY FORECAST CONCERN WILL CENTER AROUND
SEVERAL BIG TEMPERATURE SWINGS. EXPECT TWO COLD AIR OUTBREAKS...
ONE ON WEDNESDAY LASTING INTO THANKSGIVING DAY...AND A SECOND SHOT
OF COLD AIR TO FINISH THE HOLIDAY WEEKEND ON SUNDAY. HOWEVER...
FRIDAY AND SATURDAY CURRENTLY APPEAR TO BE WARM WITH HIGHS WELL
ABOVE NORMAL.
WEDNESDAY...A COLD FRONTAL PASSAGE LATE TUESDAY NIGHT WILL ALLOW
COOLER AIR TO FILTER INTO OUR REGION THROUGHOUT THE DAY. THEREFORE
...TEMPERATURES WILL WARM VERY LITTLE IF AT ALL DURING THE DAYTIME
HOURS. WE CAN NOT RULE OUT A FLURRY OR TWO WITH A LITTLE 850/700
MB MOISTURE AND COOLER AIR SETTLING IN. HOWEVER...FORECAST MODELS
CONTINUE TO BE IN GOOD AGREEMENT IN 0.00 QPF AND THE CHANCE OF
FLURRIES IS STILL TOO LOW TO INCLUDE MENTION IN THE FORECAST.
THERE COULD BE A PRETTY GOOD TEMPERATURE CONTRAST ACROSS THE
FORECAST AREA AS THE COLD AIR WILL HANG UP MORE OVER NEBRASKA.
THEREFORE...EXPECT HIGHS ON WEDNESDAY SHOULD RANGE FROM THE 30S
ACROSS SOUTH CENTRAL NEBRASKA TO THE LOWER 40S OVER NORTH CENTRAL
KANSAS.
THANKSGIVING...FORECAST MODELS ARE IN INCREASINGLY GOOD AGREEMENT
THAT WE WILL SLOWLY START TO WARM BACK UP ON THANKSGIVING DAY. AN
UPPER RIDGE WILL BEGIN TO WORK ITS WAY EAST INTO THE FORECAST AREA
BRINGING WARMER AIR ALOFT. AT THE SFC...THE WIND WILL TURN TO
SOUTHERLY AND WILL ALSO RESULT IN WARM AIR ADVECTION. THE WARMING
WILL BE GRADUAL ON THANKSGIVING WITH ONLY A FEW DEGREE RISE
EXPECTED OVER WEDNESDAY HIGHS...BUT THE WARM UP WILL INCREASE AS
WE HEAD INTO FRIDAY. AS FOR THANKSGIVING...EXPECT HIGHS IN THE
UPPER 30S NORTHEASTERN ZONES...TO AROUND 40 IN THE TRI-CITIES...TO
THE MID AND UPPER 40S OVER NORTH CENTRAL KANSAS.
FRIDAY AND SATURDAY...THE OVERALL UPPER FLOW BECOMES MORE ZONAL
WITH THE REAL COLD AIR BOXED UP IN PORTIONS OF THE DAKOTAS AND IN
CANADA. THIS WILL ALSO KEEP THE STORM TRACK WELL TO OUR NORTH
RESULTING IN CONTINUED DRY CONDITIONS. THERE IS HIGH CONFIDENCE IN
FRIDAY BEING A VERY NICE DAY WITH WARM AIR ADVECTION BOTH ALOFT
AND AT THE SFC. THE SFC WINDS WILL BE FAIRLY LIGHT BUT SHOULD HAVE
A BIT OF A DOWNSLOPE WARMING COMPONENT TO IT BEING OUT OF THE WEST
TO SOUTHWEST. ALL IN ALL EXPECT A VERY NICE DAY WITH HIGHS IN THE
MID TO UPPER 50S IN THE TRI-CITIES TO THE LOWER 60S OVER PORTIONS
OF NORTH CENTRAL KANSAS. FORECAST MODELS ARE COMING INTO BETTER
AGREEMENT WITH THE COLD FRONTAL PASSAGE TIMING ON SATURDAY.
OVERALL FORECAST MODELS HAVE LARGELY SLOWED DOWN THE COLD FRONT
AND BRING IT THROUGH OUR FORECAST AREA SATURDAY EVENING OR
SATURDAY NIGHT. THIS WILL ALLOW FOR FULL DIURNAL HEATING UNDER A
CONTINUED WARM AIR MASS WHICH SHOULD HELP ALL AREAS GET INTO THE
UPPER 50S TO LOWER 60S. THE 00Z ECMWF EVEN INDICATES A FEW SPOTS
COULD HIT 70 SATURDAY AFTERNOON. EVERYTHING HINGES ON THE TIMING
OF THE COLD FRONT...BUT RIGHT NOW SATURDAY APPEARS TO BE A GREAT
DAY TO GET OUT AND ENJOY BEFORE THE NEXT COLD SNAP HITS.
SUNDAY AND MONDAY...THERE IS CURRENTLY DECENT FORECAST AGREEMENT
BETWEEN THE 00Z GFS AND 00Z ECMWF THAT A PRETTY POTENT COLD AIR
MASS WILL OVERSPREAD THE AREA SATURDAY NIGHT INTO SUNDAY. IT
SHOULD BE A DRY FRONTAL PASSAGE SO WE ARE NOT REALLY WORRIED ABOUT
SNOW...BUT IT DOES APPEAR TO BE COLD. OUR FORECAST HIGHS BASED OFF
THE SUPERBLEND OF MODELS RANGE FROM THE UPPER 20S IN ORD TO THE
30S ELSEWHERE AND THIS MAY BE OPTIMISTICALLY TOO WARM IF YOU
BELIEVE THE DETERMINISTIC 00Z GFS AND ECMWF MODEL RUNS. THERE IS A
HIGH LEVEL OF UNCERTAINTY AS TOO HOW LONG THE COLD AIR WILL LINGER
ACROSS THE AREA AS THE 00Z GFS IS MUCH QUICKER TO PUSH THE COLD
AIR OUT ON MONDAY THAN THE 00Z ECMWF.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z WED MORNING)
ISSUED AT 545 AM CST TUE NOV 25 2014
TODAY: THICK MULTI-LAYERED VFR CIGS INVADE AROUND 18K FT AND
CASCADE DOWNWARD THRU THE DAY TO AROUND 6K FT BY SUNSET. LIGHT
SW-W WINDS WILL BECOME SW AND INCREASE...GUSTING 20-23 KTS AT
TIMES PRIMARILY AFTER 18Z. CONFIDENCE: HIGH
TONIGHT: VFR CIGS WITH A BRIEF VFR SHWR POSSIBLE 00Z-03Z. THEN A
COLD FRONTAL PASSAGE 03Z-05Z. MVFR CIGS APPEAR PROBABLE...BUT NOT
ALL GUIDANCE IS ON BOARD YET. NW WINDS WILL GUST 25-33 KTS.
CONFIDENCE: MEDIUM DUE TO UNCERTAINTY ON POSSIBLE MVFR CIGS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...HALBLAUB
LONG TERM...WESELY
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
308 AM CST TUE NOV 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CST TUE NOV 25 2014
...BECOMING CLOUDY WITH ANOTHER LIGHT PRECIP EVENT LATE THIS
AFTERNOON/EVE FOLLOWED BY MORE WIND...
ALOFT: THE FLOW WAS HIGHLY AMPLIFIED WITH A LONGWAVE TROF OVER
THE CNTRL USA AND RIDGES JUST OFF BOTH COASTS. WV IMAGERY SHOWED A
SHORTWAVE TROF OVER ALBERTA. THIS TROF WILL DIVE SE INTO THE
DAKOTAS TODAY AND INTO NEB/KS TONIGHT...DEEPENING OVER TIME WITH A
GOOD SHOT OF QG FORCING IN THE EXIT REGION OF A 150 KT UPR-LVL JET.
SURFACE: A CLIPPER LOW WAS ORGANIZING OVER ALBERTA. THIS LOW WILL
RACE INTO THE DAKOTAS TODAY AND BE LOCATED OVER WRN IA BY DAYBREAK
WED. ITS COLD FRONT WILL SWEEP THRU TONIGHT.
EARLY THIS MORNING: WAA WAS UNDERWAY. SATELLITE SHOWS ARE LARGE
EXPANSE OF LOW-MID CLOUDS OVER THE NRN PLAINS AHEAD OF THE CLIPPER
WARM FRONT. THE SRN END OF THESE CLOUDS WAS GRAZING THE FCST AREA.
COULD EVEN SEE A COUPLE FLURRIES N OF NEB HWY 92 BEFORE SUNRISE.
TODAY: WAA WILL CONT IN THE WARM SECTOR OF THE CLIPPER. MORNING
SUN WILL RAPIDLY BE OBSCURED BY INCREASING AND DESCENDING MID-HIGH
CLOUDS. ONE WEAKNESS IN THIS FCST IS THAT CLOUDS MAY COME IN THICK
FASTER THAN CURRENTLY DEPICTED. I.E. WE MAY NOT BE PESSIMISTIC
ENOUGH. THAT IS A DENSE CIRRUS SHIELD ON SATELLITE IMAGERY.
MODEL CONSENSUS INCLUDING HI-RES MODELING INDICATE A SWATH OF
FGEN-ENHANCED LIGHT RAIN AND/OR SPRINKLES WILL DEVELOP AND CROSS
THE FCST AREA FROM 3PM-12AM. SPRINKLES ARE MOST LIKELY ON THE SRN
FRINGE OF THE PRECIP SHIELD. INCLUDED SPRINKLES S AND W OF THE
MODEL CONSENSUS OF .01" QPF AS SOME SREF MEMBERS DO HINT AT THE
POSSIBILITY OF RAIN OUTSIDE OF THE BEST MODEL CLUSTERING.
USED THE 05Z BIAS CORRECTED RAP FOR HIGHS TODAY WHICH SEEMS TO
HAVE A BETTER GRASP ON WHERE THICKER CLOUDS WILL ARRIVE FROM THE
N. DESPITE THE CLOUDS SHOULD BE A MILD DAY WITH TEMPS AT OR
SLIGHTLY ABOVE NORMAL.
THERE IS CONSIDERABLE UNCERTAINTY IN DWPTS/RH TODAY WITH 10F OF
SPREAD BETWEEN THE MAV/MET MOS. USED CONSENSUS OF SHORT-TERM HI-
RES MODELS WHICH WERE NOT THE LOWEST BUT DID FAVOR THE DRIER MAV
MOS. THIS WILL WORK BEST OUTSIDE WHERE IT RAINS...BUT MOISTENING
FROM RAINFALL WILL INCREASE DWPTS LOCALLY.
TONIGHT: SWATH OF RAIN/SPRINKLES EXITS TO THE E BY MIDNIGHT.
STRONG CAA KICKS IN AFTER PASSAGE OF THE COLD FRONT WITH A CORE OF
50 KT WINDS AT 850 MB. OUTPUT FROM THE WIND GUST TOOL SEEMED TOO
LOW SO USED GUSTS FROM A BLEND OF THE 18Z/00Z RAW MODEL GUIDANCE
/CONSRAW/. NW WINDS WILL GUST 30-35 KTS N OF HWY 6 BEGINNING 3 AM.
WITH 40 KTS AS LOW AS 1500 FT...CAN`T RULE OUT ISOLATED HIGHER
GUSTS.
P-TYPE: KEPT IT PRIMARILY RAIN/SPRINKLES EXCEPT ON THE EXTREME
NE/E FRINGES OF THE FCST AREA 07Z-08Z ON THE BACK EDGE OF THE
PRECIP...IF IT`S STILL FALLING BY THEN. NAM P-TYPE ALGORITHM KEEPS
IT ALL RAIN AND FCST SOUNDINGS SUGGEST THE LEFTOVER DAYTIME BL
WILL BE TOO WARM TO SUPPORT SNOW. EVEN WETBULB TEMPS FAVOR RAIN
WITH +2 UP TO 1K FT. CURRENT INDICATIONS ARE THAT THE PRECIP
SHOULD BE OVER BY THE TIME TEMP PROFILES COOL ENOUGH FOR SNOW.
MODEL 2M TEMPS SUGGEST A FAIRLY MILD NIGHT WITH LOWS 27-38F AND
30-31F IN THE TRI-CITIES. EVEN THE MOS 3-HOURLY TEMPS SUGGEST
THIS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 308 AM CST TUE NOV 25 2014
WE ARE CALLING FOR A DRY FORECAST FROM START TO FINISH THIS
HOLIDAY WEEKEND. THE PRIMARY FORECAST CONCERN WILL CENTER AROUND
SEVERAL BIG TEMPERATURE SWINGS. EXPECT TWO COLD AIR OUTBREAKS...
ONE ON WEDNESDAY LASTING INTO THANKSGIVING DAY...AND A SECOND SHOT
OF COLD AIR TO FINISH THE HOLIDAY WEEKEND ON SUNDAY. HOWEVER...
FRIDAY AND SATURDAY CURRENTLY APPEAR TO BE WARM WITH HIGHS WELL
ABOVE NORMAL.
WEDNESDAY...A COLD FRONTAL PASSAGE LATE TUESDAY NIGHT WILL ALLOW
COOLER AIR TO FILTER INTO OUR REGION THROUGHOUT THE DAY. THEREFORE
...TEMPERATURES WILL WARM VERY LITTLE IF AT ALL DURING THE DAYTIME
HOURS. WE CAN NOT RULE OUT A FLURRY OR TWO WITH A LITTLE 850/700
MB MOISTURE AND COOLER AIR SETTLING IN. HOWEVER...FORECAST MODELS
CONTINUE TO BE IN GOOD AGREEMENT IN 0.00 QPF AND THE CHANCE OF
FLURRIES IS STILL TOO LOW TO INCLUDE MENTION IN THE FORECAST.
THERE COULD BE A PRETTY GOOD TEMPERATURE CONTRAST ACROSS THE
FORECAST AREA AS THE COLD AIR WILL HANG UP MORE OVER NEBRASKA.
THEREFORE...EXPECT HIGHS ON WEDNESDAY SHOULD RANGE FROM THE 30S
ACROSS SOUTH CENTRAL NEBRASKA TO THE LOWER 40S OVER NORTH CENTRAL
KANSAS.
THANKSGIVING...FORECAST MODELS ARE IN INCREASINGLY GOOD AGREEMENT
THAT WE WILL SLOWLY START TO WARM BACK UP ON THANKSGIVING DAY. AN
UPPER RIDGE WILL BEGIN TO WORK ITS WAY EAST INTO THE FORECAST AREA
BRINGING WARMER AIR ALOFT. AT THE SFC...THE WIND WILL TURN TO
SOUTHERLY AND WILL ALSO RESULT IN WARM AIR ADVECTION. THE WARMING
WILL BE GRADUAL ON THANKSGIVING WITH ONLY A FEW DEGREE RISE
EXPECTED OVER WEDNESDAY HIGHS...BUT THE WARM UP WILL INCREASE AS
WE HEAD INTO FRIDAY. AS FOR THANKSGIVING...EXPECT HIGHS IN THE
UPPER 30S NORTHEASTERN ZONES...TO AROUND 40 IN THE TRI-CITIES...TO
THE MID AND UPPER 40S OVER NORTH CENTRAL KANSAS.
FRIDAY AND SATURDAY...THE OVERALL UPPER FLOW BECOMES MORE ZONAL
WITH THE REAL COLD AIR BOXED UP IN PORTIONS OF THE DAKOTAS AND IN
CANADA. THIS WILL ALSO KEEP THE STORM TRACK WELL TO OUR NORTH
RESULTING IN CONTINUED DRY CONDITIONS. THERE IS HIGH CONFIDENCE IN
FRIDAY BEING A VERY NICE DAY WITH WARM AIR ADVECTION BOTH ALOFT
AND AT THE SFC. THE SFC WINDS WILL BE FAIRLY LIGHT BUT SHOULD HAVE
A BIT OF A DOWNSLOPE WARMING COMPONENT TO IT BEING OUT OF THE WEST
TO SOUTHWEST. ALL IN ALL EXPECT A VERY NICE DAY WITH HIGHS IN THE
MID TO UPPER 50S IN THE TRI-CITIES TO THE LOWER 60S OVER PORTIONS
OF NORTH CENTRAL KANSAS. FORECAST MODELS ARE COMING INTO BETTER
AGREEMENT WITH THE COLD FRONTAL PASSAGE TIMING ON SATURDAY.
OVERALL FORECAST MODELS HAVE LARGELY SLOWED DOWN THE COLD FRONT
AND BRING IT THROUGH OUR FORECAST AREA SATURDAY EVENING OR
SATURDAY NIGHT. THIS WILL ALLOW FOR FULL DIURNAL HEATING UNDER A
CONTINUED WARM AIR MASS WHICH SHOULD HELP ALL AREAS GET INTO THE
UPPER 50S TO LOWER 60S. THE 00Z ECMWF EVEN INDICATES A FEW SPOTS
COULD HIT 70 SATURDAY AFTERNOON. EVERYTHING HINGES ON THE TIMING
OF THE COLD FRONT...BUT RIGHT NOW SATURDAY APPEARS TO BE A GREAT
DAY TO GET OUT AND ENJOY BEFORE THE NEXT COLD SNAP HITS.
SUNDAY AND MONDAY...THERE IS CURRENTLY DECENT FORECAST AGREEMENT
BETWEEN THE 00Z GFS AND 00Z ECMWF THAT A PRETTY POTENT COLD AIR
MASS WILL OVERSPREAD THE AREA SATURDAY NIGHT INTO SUNDAY. IT
SHOULD BE A DRY FRONTAL PASSAGE SO WE ARE NOT REALLY WORRIED ABOUT
SNOW...BUT IT DOES APPEAR TO BE COLD. OUR FORECAST HIGHS BASED OFF
THE SUPERBLEND OF MODELS RANGE FROM THE UPPER 20S IN ORD TO THE
30S ELSEWHERE AND THIS MAY BE OPTIMISTICALLY TOO WARM IF YOU
BELIEVE THE DETERMINISTIC 00Z GFS AND ECMWF MODEL RUNS. THERE IS A
HIGH LEVEL OF UNCERTAINTY AS TOO HOW LONG THE COLD AIR WILL LINGER
ACROSS THE AREA AS THE 00Z GFS IS MUCH QUICKER TO PUSH THE COLD
AIR OUT ON MONDAY THAN THE 00Z ECMWF.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z TUE NIGHT)
ISSUED AT 1131 PM CST MON NOV 24 2014
OVERNIGHT: VFR WITH SCT PATCHES OF 7K ALTOCU DRIFTING THRU. WINDS
WILL BE LIGHT FROM THE W. CONFIDENCE: HIGH
TUE: MULTI-LAYERED VFR CIGS MOVE IN AND GRADUALLY DESCEND DOWN TO
ROUGHLY 9K FT. WINDS BECOME SW 10-15 KTS. CONFIDENCE: HIGH
TUE EVE: VFR CIGS DESCEND TO AROUND 4K FT WITH POTENTIAL FOR A
PERIOD OF MVFR CIGS WITH A BIT OF -RA POSSIBLE. COLD FRONTAL
PASSAGE AND WSHFT EXPECTED AROUND 03Z. CONFIDENCE: MEDIUM
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...HALBLAUB
LONG TERM...WESELY
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1016 PM EST WED NOV 26 2014
.SYNOPSIS...
SNOW WILL DIMINISH TO AREAS OF LIGHT SNOW AND FLURRIES TONIGHT AS
THE STORM THAT BROUGHT HEAVY SNOW TO PARTS OF THE AREA EARLIER
TODAY MOVES NORTHEAST TOWARD THE CANADIAN MARITIMES. A SERIES OF
UPPER- LEVEL DISTURBANCES WILL BRING OCCASIONAL LIGHT SNOW SHOWERS
AND FLURRIES THURSDAY THROUGH SATURDAY...WITH TEMPERATURES STAYING
ON THE CHILLY SIDE.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
UPDATED AT 1015 PM... LOW PRESSURE WILL BE TRACKING EAST OF CAPE
COD OVERNIGHT AND THE BAND OF HEAVY SNOW THAT PERSISTED OVER
PORTIONS OF THE AREA EARLIER TODAY HAS NOW MOVED EAST OFF TO THE
EAST. AREAS OF LIGHT SNOW AND FLURRIES REMAIN IN THE WAKE OF THE
STORM OVERNIGHT AS LOTS OF LOW AND MID-LEVEL MOISTURE WILL
REMAIN IN PLACE. IN ADDITION SOME WEAK LIFT WILL BE GENERATED BY
THE PRESENCE OF WEAK SURFACE TROUGHING OVER NEW YORK STATE IN
THE LIGHT NNW FLOW REGIME. TEMPERATURES WILL BE MARGINALLY COLD
ENOUGH FOR SOME LAKE ENHANCEMENT BUT THE FLOW IS VERY LIGHT AND
EXPECT ADDITIONAL ACCUMULATIONS GENEARLLY LESS THAN AN INCH. HAVE
CANCELLED THE WINTER WEATHER ADVISORIES FOR THE CENTRAL SOUTHERN
TIER AND EASTERN FINGER LAKES AS REPORTS ARE INDICATING THAT MAIN
ROADWAYS ARE MOSTLY JUST WET... ALTHOUGH FALLING TEMPERATURES
COULD STILL LEAD TO SOME ICY SPOTS IN THOSE AREAS... AND SOME
SECONDARY ROADS COULD STILL BE SNOW COVERED. FARTHER EAST WILL LET
THE WARNINGS CONTINUE FOR AWHILE AS ROADS WILL STILL BE HAZARDOUS
AND SNOW COVERED IN MANY AREAS DESPITE ONLY LIGHT SNOW EXPECTED
OVERNIGHT. PREVIOUS DISCUSSION IS BELOW.
UPDATED AT 615 PM... SURFACE LOW PRESSURE WELL EAST OF THE NJ
COAST CONTINUES TO TRACK NORTHEAST EARLY THIS EVENING WTIH THE 700
MB BEGINNING TO CLOSE OFF OVER NORTHEAST PA AND SOUTHEAST NY.
PERSISTENT BAND OF MID-LEVEL FRONTOGENESIS CONTINUES TO BE THE
MAIN DRIVER OF A PERSISTENT SNOW BAND THAT HAS BEEN OVER OUR
CENTRAL COUNTIES FOR THE PAST SEVERAL HOURS. THIS FORCING WILL BE
MOVING OFF TO THE EAST DURING THE NEXT FEW HOURS.
THE PERSISTENT BAND OF HEAVY SNOW IS FINALLY BEGINNING TO MOVE
EAST NOW WITH SNOW BEGINNING TO DIMINISH TO THE WEST OF THE BAND.
SNOWFALL TOTALS WITHIN THIS BAND HAVE BEEN MOSTLY IN THE 7 TO 10
INCH RANGE FROM BRADFORD TO BROOME TO CHENANGO COUNTIES. WITH THIS
BAND NOW MOVING EAST EXPECT SNOW TO DIMINISH RAPIDLY IN INTENSITY
WEST OF I-81 AFTER 7 PM... AND OVER OUR EASTERN COUNTIES BY
MIDNIGHT. SNOWFALL WITHIN THE BAND IS STILL PRETTY INTENSE WITH
RATES OF 1 TO 2 INCHES PER HOUR. BASED ON THE EXPECTED EVOLUTION
OF THE STORM ANOTHER 2 TO 4 INCHES OF SNOW CAN BE EXPECTED EAST OF
I-81 THIS EVENING WITH LESS THAN 2 INCHES THE WEST. BASED ON THIS
OUR CURRENT WARNING CONFIGURATION LOOKS VERY GOOD... WITH WARNINGS
CONTINUING ALONG AND EAST OF A LINE FROM BRADFORD TO TIOGA TO BROOME
TO CHENANGO COUNTIES FOR UP TO 12 INCHES OF SNOW... AND A STRIPE
OF ADVISORIES FOR 3 TO 6 INCHES JUST TO THE WEST. HAVE MADE SOME
MINOR CHANGES TO SNOWFALL FORECASTS WITH THIS UPDATE... OTHERWISE
NO SIGNIFICANT CHANGES. PREVIOUS DISCUSSION IS BELOW.
4 PM UPDATE... BASED ON PERSISTENCE OF NARROW CSI BAND...AND THE
EXPECTATION OF ANOTHER 2-3 HRS OF +SN UNDERNEATH IT...WE`VE ADDED
BRADFORD PA AND TIOGA NY TO THE WRNG AREA (STORM TOTALS OF
5-10").
3 PM UPDATE... FOR THE MOST PART...ONGOING WINTER STORM IS
BEHAVING ITSELF...AS A DEEPENING SURFACE CYCLONE IS MOVING NEWD
OFF THE MID-ATLANTIC COAST.
OF PRIMARY CONCERN LATE THIS AFTN INTO THE EVE HRS IS THE TRACK
OF THE MID-LVL LOW (700 MB)...AND AN ASSOCD BAND OF FGEN
FORCING...FROM CNTRL/NERN PA INTO PTNS OF NY`S SRN TIER...THEN
NEWD FROM THERE. BASED ON THE LATEST OBSERVATIONAL DATA...SPC
MESO-ANALYSES...AND THE LATEST HI-RES MODEL OUTPUT...THE MAIN BAND
OF +SN MAY WELL IMPACT AN AXIS FROM NEAR WILLIAMSPORT...TO
TOWANDA...TO BINGHAMTON...TO NORWICH AND COOPERSTOWN THROUGH AT
LEAST 21-23Z...WITH A GENERAL EWD SHIFT THEREAFTER. ACRS OUR SERN
ZNS...PROXIMITY OF A MID-LVL DRY SLOT MAY CAUSE SNOW TO OCNLLY
DECREASE...BUT IT`S NOT LIKELY TO SHUT DOWN ALTOGETHER UNTIL LTR
THIS EVE...SO ADDITIONAL ACCUMS ARE STILL ANTICIPATED EVEN IN
THESE AREAS. ALL IN ALL...CURRENTLY ADVERTISED SNOWFALL TOTALS
STILL LOOK REASONABLE...WITH A GENERAL 6-12" IN THE WRNG
AREA OVER MOST OF NERN PA...THE CATSKILLS...AND SXNS OF THE SUSQ RGN...AND
ROUGHLY 3-6" IN THE ADVISORY RGN...FROM KELM-KITH-KSYR.
BASED ON THE LATEST HRRR DATA...WHICH HAS PERFORMED WELL TDY...THE
BACK EDGE OF THE STEADIER SNOW PULLS OUT FROM W TO E AFTER 01-03Z.
ALTHOUGH WE COULD SEE SOME WEAK MULTI-BANDS TWDS DAYBREAK IN A
310-330 FLOW...THE OVERALL FLOW LOOKS WEAK...AND MOISTURE DEPTHS
WILL BE ON THE DECLINE...SO ACCUMS SHOULD BE VERY MINOR.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
FOR THANKSGIVING DAY AND THU NGT...A NW FLOW PATN WILL
PREVAIL...WITH LOW-LVL CAA...AND LINGERING BLYR MOISTURE. FOR THE
MOST PART...THIS WILL PRODUCE -SHSN AND FLRYS...AND SMALL ACCUMS.
HOWEVER...A BRIEF PD OF ENHANCEMENT COULD OCCUR LTR THU NGT INTO
FRI MRNG...WHEN A WELL DEFINED NRN STREAM S/WV CROSSES NY/PA. SOME
SYNOPTIC SUPPORT FROM THE S/WV AND LK ENHANCEMENT COULD PRODUCE
LOCALLY 1-3" IN AN AXIS FROM SRN CAYUGA-ONONDAGA...TO SRN
ONEIDA/MADISON/NRN CHENANGO/NRN OTSEGO.
FOR THE REST OF THE DAY FRI INTO FRI NGT...MAINLY JUST SCTD
-SHSN/FLRYS ARE AGN ANTICIPATED...WITH BACKING LOW-LVL FLOW...AS
SOME WARM ADVECTION BEGINS.
ANOTHER S/WV PASSAGE...ALG WITH THE APPROACH OF THE SFC-850 MB
WARM FRNT FROM THE SW...COULD LEAD TO ADDTNL -SHSN AND SOME LGT
ACCUMS AS WE HEAD INTO EARLY SAT...SPCLY FOR OUR NRN ZNS.
DAILY HIGHS WILL GENERALLY BE IN THE 30S...WITH LOWS IN THE UPR
TEENS AND 20S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
230 PM EST UPDATE...
FOLLOWED CLOSELY WITH WPC GUIDANCE AND MADE MINOR CHANGES TO THE
PREVIOUS FORECAST.
THE MAIN THEME OF THE FORECAST CONTINUES WITH ZONAL FLOW STILL
BEING EXPECTED ACROSS MUCH OF THE NORTHEAST THROUGH THE FORECAST
PERIOD.
BY SAT NIGHT A WARM FRONT WILL HAVE JUST PASSED TO THE NORTH OF
THE CWA AND A COLD FRONT WILL BE STARTING TO APPROACH THE REGION
FROM THE WEST. THIS COLD FRONT WILL BRING COOLER AIR TO THE REGION
ALONG WITH A CHANCE FOR RAIN/AND OR SNOW SHOWERS TO NEW YORK AND
PENNSYLVANIA. A SFC RIDGE WILL THEN START TO BUILD OVER THE AREA
FROM THE WEST MONDAY AFTERNOON... THUS BRINGING DRY AND QUIET
WEATHER BACK TO THE AREA THROUGH MID WEEK. THIS RIDGE WILL ALSO ALLOW
TEMPERATURES OVER THE REGION TO FALL BELOW THE SEASONAL NORM. THE
COLDEST DAY IN THE EXTENDED FORECAST WILL BE WHEN THE RIDGE IS EXPECTED
TO BE CENTERED OVER THE CWA. THIS WILL OCCUR ON TUESDAY. HIGH
TEMPERATURES ARE EXPECTED TO RISE INTO THE LOW TO MID 30S.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
AN INTENSE BAND OF SNOW EXTENDING FROM NORTHEASTERN NY TOWARD THE
AVP TERMINAL WILL CAUSE IFR CONDITIONS FOR A FEW MORE HOURS. THE
SNOW WILL TAPER OFF BETWEEN 2Z AND 5Z, WITH MOST TERMINALS POPPING
BACK UP TO BETWEEN 2SM AND 5SM VISIBILITY ONCE THE BAND MOVES OUT
OR WEAKENS.
A GENERAL LIGHT SNOWFALL WILL PERSIST INTO EARLY THURSDAY WITH
LIGHT WINDS AND MAINLY MFVR RESTRICTIONS.
OUTLOOK...
THU NGT/FRI/SAT...POSSIBLE RESTRICTIONS FROM SCT -SHSN...ESPECIALLY
KSYR-KRME.
SUN...RESTRICTIONS POSSIBLE FROM -SHRA.
MON...RESTRICTIONS POSSIBLE FROM -SHRA/SHSN.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR PAZ038>040-
043-044-047-048-072.
NY...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR NYZ045-046-
055>057-062.
&&
$$
SYNOPSIS...MLJ
NEAR TERM...MLJ/MSE
SHORT TERM...MLJ
LONG TERM...KAH
AVIATION...DJP/PCF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
632 PM EST WED NOV 26 2014
.SYNOPSIS...
SNOW WILL CONTINUE INTO THIS EVENING...BEFORE WINDING DOWN LATE
TONIGHT...AS A STRENGTHENING STORM SYSTEM TRACKS FARTHER OFF THE
EAST COAST. A SERIES OF UPPER-LEVEL DISTURBANCES WILL BRING
OCCASIONAL LIGHT SNOW SHOWERS AND FLURRIES FRIDAY AND
SATURDAY...WITH TEMPERATURES STAYING ON THE CHILLY SIDE.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
UPDATED AT 615 PM... SURFACE LOW PRESSURE WELL EAST OF THE NJ
COAST CONTINUES TO TRACK NORTHEAST EARLY THIS EVENING WTIH THE 700
MB BEGINNING TO CLOSE OFF OVER NORTHEAST PA AND SOUTHEAST NY.
PERSISTENT BAND OF MID-LEVEL FRONTOGENESIS CONTINUES TO BE THE
MAIN DRIVER OF A PERSISTENT SNOW BAND THAT HAS BEEN OVER OUR
CENTRAL COUNTIES FOR THE PAST SEVERAL HOURS. THIS FORCING WILL BE
MOVING OFF TO THE EAST DURING THE NEXT FEW HOURS.
THE PERSISTENT BAND OF HEAVY SNOW IS FINALLY BEGINNING TO MOVE
EAST NOW WITH SNOW BEGINNING TO DIMINISH TO THE WEST OF THE BAND.
SNOWFALL TOTALS WITHIN THIS BAND HAVE BEEN MOSTLY IN THE 7 TO 10
INCH RANGE FROM BRADFORD TO BROOME TO CHENANGO COUNTIES. WITH THIS
BAND NOW MOVING EAST EXPECT SNOW TO DIMINISH RAPIDLY IN INTENSITY
WEST OF I-81 AFTER 7 PM... AND OVER OUR EASTERN COUNTIES BY
MIDNIGHT. SNOWFALL WITHIN THE BAND IS STILL PRETTY INTENSE WITH
RATES OF 1 TO 2 INCHES PER HOUR. BASED ON THE EXPECTED EVOLUTION
OF THE STORM ANOTHER 2 TO 4 INCHES OF SNOW CAN BE EXPECTED EAST OF
I-81 THIS EVENING WITH LESS THAN 2 INCHES THE WEST. BASED ON THIS
OUR CURRENT WARNING CONFIGURATION LOOKS VERY GOOD... WITH WARNINGS
CONTINUING ALONG AND EAST OF A LINE FROM BRADFORD TO TIOGA TO BROOME
TO CHENANGO COUNTIES FOR UP TO 12 INCHES OF SNOW... AND A STRIPE
OF ADVISORIES FOR 3 TO 6 INCHES JUST TO THE WEST. HAVE MADE SOME
MINOR CHANGES TO SNOWFALL FORECASTS WITH THIS UPDATE... OTHERWISE
NO SIGNIFICANT CHANGES. PREVIOUS DISCUSSION IS BELOW.
4 PM UPDATE... BASED ON PERSISTENCE OF NARROW CSI BAND...AND THE
EXPECTATION OF ANOTHER 2-3 HRS OF +SN UNDERNEATH IT...WE`VE ADDED
BRADFORD PA AND TIOGA NY TO THE WRNG AREA (STORM TOTALS OF
5-10").
3 PM UPDATE... FOR THE MOST PART...ONGOING WINTER STORM IS
BEHAVING ITSELF...AS A DEEPENING SURFACE CYCLONE IS MOVING NEWD
OFF THE MID-ATLANTIC COAST.
OF PRIMARY CONCERN LATE THIS AFTN INTO THE EVE HRS IS THE TRACK
OF THE MID-LVL LOW (700 MB)...AND AN ASSOCD BAND OF FGEN
FORCING...FROM CNTRL/NERN PA INTO PTNS OF NY`S SRN TIER...THEN
NEWD FROM THERE. BASED ON THE LATEST OBSERVATIONAL DATA...SPC
MESO-ANALYSES...AND THE LATEST HI-RES MODEL OUTPUT...THE MAIN BAND
OF +SN MAY WELL IMPACT AN AXIS FROM NEAR WILLIAMSPORT...TO
TOWANDA...TO BINGHAMTON...TO NORWICH AND COOPERSTOWN THROUGH AT
LEAST 21-23Z...WITH A GENERAL EWD SHIFT THEREAFTER. ACRS OUR SERN
ZNS...PROXIMITY OF A MID-LVL DRY SLOT MAY CAUSE SNOW TO OCNLLY
DECREASE...BUT IT`S NOT LIKELY TO SHUT DOWN ALTOGETHER UNTIL LTR
THIS EVE...SO ADDITIONAL ACCUMS ARE STILL ANTICIPATED EVEN IN
THESE AREAS. ALL IN ALL...CURRENTLY ADVERTISED SNOWFALL TOTALS
STILL LOOK REASONABLE...WITH A GENERAL 6-12" IN THE WRNG
AREA OVER MOST OF NERN PA...THE CATSKILLS...AND SXNS OF THE SUSQ RGN...AND
ROUGHLY 3-6" IN THE ADVISORY RGN...FROM KELM-KITH-KSYR.
BASED ON THE LATEST HRRR DATA...WHICH HAS PERFORMED WELL TDY...THE
BACK EDGE OF THE STEADIER SNOW PULLS OUT FROM W TO E AFTER 01-03Z.
ALTHOUGH WE COULD SEE SOME WEAK MULTI-BANDS TWDS DAYBREAK IN A
310-330 FLOW...THE OVERALL FLOW LOOKS WEAK...AND MOISTURE DEPTHS
WILL BE ON THE DECLINE...SO ACCUMS SHOULD BE VERY MINOR.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
FOR THANKSGIVING DAY AND THU NGT...A NW FLOW PATN WILL
PREVAIL...WITH LOW-LVL CAA...AND LINGERING BLYR MOISTURE. FOR THE
MOST PART...THIS WILL PRODUCE -SHSN AND FLRYS...AND SMALL ACCUMS.
HOWEVER...A BRIEF PD OF ENHANCEMENT COULD OCCUR LTR THU NGT INTO
FRI MRNG...WHEN A WELL DEFINED NRN STREAM S/WV CROSSES NY/PA. SOME
SYNOPTIC SUPPORT FROM THE S/WV AND LK ENHANCEMENT COULD PRODUCE
LOCALLY 1-3" IN AN AXIS FROM SRN CAYUGA-ONONDAGA...TO SRN
ONEIDA/MADISON/NRN CHENANGO/NRN OTSEGO.
FOR THE REST OF THE DAY FRI INTO FRI NGT...MAINLY JUST SCTD
-SHSN/FLRYS ARE AGN ANTICIPATED...WITH BACKING LOW-LVL FLOW...AS
SOME WARM ADVECTION BEGINS.
ANOTHER S/WV PASSAGE...ALG WITH THE APPROACH OF THE SFC-850 MB
WARM FRNT FROM THE SW...COULD LEAD TO ADDTNL -SHSN AND SOME LGT
ACCUMS AS WE HEAD INTO EARLY SAT...SPCLY FOR OUR NRN ZNS.
DAILY HIGHS WILL GENERALLY BE IN THE 30S...WITH LOWS IN THE UPR
TEENS AND 20S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
230 PM EST UPDATE...
FOLLOWED CLOSELY WITH WPC GUIDANCE AND MADE MINOR CHANGES TO THE
PREVIOUS FORECAST.
THE MAIN THEME OF THE FORECAST CONTINUES WITH ZONAL FLOW STILL
BEING EXPECTED ACROSS MUCH OF THE NORTHEAST THROUGH THE FORECAST
PERIOD.
BY SAT NIGHT A WARM FRONT WILL HAVE JUST PASSED TO THE NORTH OF
THE CWA AND A COLD FRONT WILL BE STARTING TO APPROACH THE REGION
FROM THE WEST. THIS COLD FRONT WILL BRING COOLER AIR TO THE REGION
ALONG WITH A CHANCE FOR RAIN/AND OR SNOW SHOWERS TO NEW YORK AND
PENNSYLVANIA. A SFC RIDGE WILL THEN START TO BUILD OVER THE AREA
FROM THE WEST MONDAY AFTERNOON... THUS BRINGING DRY AND QUIET
WEATHER BACK TO THE AREA THROUGH MID WEEK. THIS RIDGE WILL ALSO ALLOW
TEMPERATURES OVER THE REGION TO FALL BELOW THE SEASONAL NORM. THE
COLDEST DAY IN THE EXTENDED FORECAST WILL BE WHEN THE RIDGE IS EXPECTED
TO BE CENTERED OVER THE CWA. THIS WILL OCCUR ON TUESDAY. HIGH
TEMPERATURES ARE EXPECTED TO RISE INTO THE LOW TO MID 30S.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AN INTENSE BAND OF SNOW EXTENDING FROM NORTHEASTERN NY TOWARD THE
AVP TERMINAL WILL CAUSE IFR CONDITIONS FOR A FEW MORE HOURS. THE
SNOW WILL TAPER OFF BETWEEN 2Z AND 5Z, WITH MOST TERMINALS POPPING
BACK UP TO BETWEEN 2SM AND 5SM VISIBILITY ONCE THE BAND MOVES OUT
OR WEAKENS.
A GENERAL LIGHT SNOWFALL WILL PERSIST INTO EARLY THURSDAY WITH
LIGHT WINDS AND MAINLY MFVR RESTRICTIONS.
OUTLOOK...
THU NGT/FRI/SAT...POSSIBLE RESTRICTIONS FROM SCT -SHSN...ESPECIALLY
KSYR-KRME.
SUN...RESTRICTIONS POSSIBLE FROM -SHRA.
MON...RESTRICTIONS POSSIBLE FROM -SHRA/SHSN.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR PAZ038>040-
043-044-047-048-072.
NY...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR NYZ045-046-
055>057-062.
WINTER WEATHER ADVISORY UNTIL 6 AM EST THURSDAY FOR NYZ009-017-
018-024-025-036-037-044.
&&
$$
SYNOPSIS...MLJ
NEAR TERM...MLJ/MSE
SHORT TERM...MLJ
LONG TERM...KAH
AVIATION...DJP/PCF
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
925 AM EST TUE NOV 25 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE OFFSHORE BY MID-MORNING. LOW PRESSURE WILL
FORM ON THE FRONT AND MOVE NORTH ALONG THE NORTH CAROLINA COAST ON
WEDNESDAY. A WEAK BOUNDARY WILL MOVE THROUGH THE AREA ON THURSDAY.
HIGH PRESSURE WILL BUILD INTO THE AREA FRIDAY AND REMAIN THROUGH
THE WEEKEND. A COLD FRONT WILL DROP THROUGH THE AREA MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 921 AM TUE...FRONT OVER THE CENTRAL PART OF NORTH CAROLINA
WILL MOVE SLOWLY EASTWARD AND AS PER HRRR WILL CROSS EASTERN NORTH
CAROLINA DURING THE EARLY AFTERNOON HOURS. LINE OF SHOWERS OVER
EASTERN NORTH CAROLINA WILL ONLY SLOWLY MOVE EASTWARD IN DEEP
LAYERED SOUTHWEST FLOW. BLENDED PRECIPITABLE WATER VALUES AVERAGE
ABOUT 1.5 INCHES. HEAVIER SHOWERS PRODUCING UP TO AN INCH OF RAIN IN
AN HOUR. ISOLATED THUNDERSTORMS ARE ALSO SEEN ON RADAR. UPPER LEVEL
ENERGY WILL REMAIN OVER THE AREA THROUGH THE DAY AND AS SURFACE
FRONT APPROACHES...EXPECT AN INCREASE IN PRECIPITATION COVERAGE.
TEMPERATURES ARE CURRENTLY IN THE 60S. WITH CLOUD COVER...
PRECIPITATION...AND PASSAGE OF COLD FRONT...AM NOT EXPECTING MUCH OF
AN INCREASE IN TEMPERATURES THROUGH THE DAY. WE MAY HAVE ALREADY
REACHED OUR HIGH TEMPERATURES.
&&
.SHORT TERM / WEDNESDAY THROUGH 6 AM WEDNESDAY/...
AS OF 335 AM TUESDAY...MAIN WAVE OF LOW PRESSURE DEVELOPS AND
RAPIDLY STRENGTHENS EAST OF THE NORTH CAROLINA COAST BY LATE
TONIGHT AND EARLY WEDNESDAY MORNING. EXPECT WIDESPREAD RAIN WITH
GUSTY NORTHERLY WINDS DEVELOPING AFTER MIDNIGHT. TEMPERATURES WILL
BE COOLER WITH CANADIAN AIR FILTERING IN BEHIND THE DEPARTING LOW.
EXPECT MINIMUM TEMPERATURES TONIGHT IN THE MID 40S INLAND TO MID
50S OUTER BANKS. POPS ARE CATEGORICAL AND SOME AREAS...ESPECIALLY
NEAR THE COAST COULD RECEIVE 1 TO 2 INCHES OF RAINFALL.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
ACTIVE WEATHER AT THE BEGINNING OF THE LONG TERM FORECAST PERIOD
THEN SETTLING IN TO A MORE BENIGN WEATHER PATTERN STARTING LATE IN
THE WEEK AND THROUGH THE WEEKEND. A DEEP UPPER TROUGH MOVES THROUGH
THE EASTERN STATES WED/THU THEN THE UPPER FLOW TRANSITIONS TO A MORE
ZONAL FLOW THROUGH EARLY NEXT WEEK.
DEEPENING SFC LOW PRESSURE WILL BE SKIRTING THE NC COAST WEDNESDAY
BEFORE LIFTING NORTHEAST OF THE OUTER BANKS LATE IN THE DAY. A SOLID
AREA OF MODERATE RAIN IN THE BAROCLINIC ZONE OVER EASTERN NORTHERN
WILL SWEEP THROUGH THE AREA THROUGH MIDDAY THEN RAIN CHANCES WILL
BEGIN TO TAPER OFF FROM SW TO NE DURING THE AFTERNOON. AN ADDITIONAL
1-3 INCHES OF RAIN IS LIKELY THROUGH WEDNESDAY AND THIS MAY LEAD TO
MINOR/LOCALIZED FLOODING DURING THIS BUSY TRAVEL PERIOD BUT
WIDESPREAD FLOOD PROBLEMS NOT EXPECTED. OTHER THAN FOR COASTAL
AREAS, THERE WONT BE MUCH OF A DIURNAL TEMPERATURE RISE WITH
READINGS STUCK IN THE MID AND UPPER 40S AWAY FROM THE COAST WED.
DEPENDING ON THE EXACT TRACK OF THE LOW, WARM SECTOR TEMPS MAY RISE
INTO THE 60S ALONG THE COAST.
LOW LEVEL DRIER AIR WILL FILTER INTO THE AREA ON NW WINDS AS THE SFC
LOW MOVES WELL TO THE NE WED NIGHT INTO THURSDAY. THE PASSAGE OF A
MID LEVEL TROUGH JUST TO THE NORTH MAY PROVIDE SOME MID LEVEL
CLOUDINESS BUT EXPECT ANY PRECIP TO REMAIN NORTH OF THE FORECAST
AREA LATE WED NIGHT THRU THURSDAY. COLD AIR ADVECTION WILL DROP
TEMPS INTO THE MID 30S INLAND AND LOW 40S COAST WED NIGHT WITH HIGHS
ON THURSDAY MAINLY IN THE LOW 50S. ALSO A SECONDARY SURGE OF CAA
WILL ACCOMPANY THE PASSAGE OF THE MID LEVEL TROF WITH TEMPS
REMAINING WELL BLO NORMAL THURSDAY NIGHT THRU FRIDAY NIGHT.
A GRADUAL WARMING TREND AND A CONTINUATION OF DRY WEATHER WILL
HIGHLIGHT WEATHER DURING THE WEEKEND AND INTO EARLY NEXT WEEK AS SFC
HIGH PRESSURE TRANSITS THROUGH THE AREA. TEMPERATURES RETURN TO NEAR
OR EVEN A LITTLE ABOVE NORMAL SUNDAY AND POSSIBLY INTO MONDAY. MODEL
CONCENSUS FAVORS A WEAK/DRY COLD FRONT PASSAGE LATE MONDAY WHICH MAY
KNOCK TEMPS BACK A FEW DEGS MON NIGHT INTO TUESDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 640 AM TUESDAY...GENERALLY VFR CONDITIONS CONTINUES AT THE TAF
SITES. AS RAIN COVERAGE INCREASES WITH APPROACH OF COLD
FRONT...EXPECT CEILINGS AND VSBYS TO LOWER BY MID MORNING TO MVFR
WITH WIDESPREAD IFR BY LATE AFTERNOON INTO TONIGHT. A STEADY
RAINFALL SHOULD KEEP CONDITIONS IN IFR RANGE INTO WEDNESDAY MORNING.
GUSTY NORTH TO NORTHWEST WINDS ARE LIKELY BY LATE TONIGHT.
LONG TERM /WEDNESDAY THROUGH SUNDAY/...
A SOLID AREA OF RAIN WILL BRING LIKELY IFR CONDITIONS AT LEAST THRU
MIDDAY WEDNESDAY. MAY BEING TO SEE IMPROVING CONDITIONS AS THE SFC
LOW MOVES NE OF THE AREA WED AFTERNOON BUT MAY NOT SEE VFR
CONDITIONS RETURNING UNTIL LATE IN THE DAY. THEREAFTER EXPECT A
PROLONGED PERIOD OF MAINLY VFR CONDITIONS AS SFC HIGH PRESSURE
GRADUALLY APPROACHES DURING THE LATTER PART OF THE WEEK THEN
TRANSITS THE AREA DURING THE WEEKEND. MAY SEE PERIODS OF LATE NIGHT
PATCHY FOG OVER THE WEEKEND.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 924 AM TUE...GENERALLY SOUTHWESTERLY FLOW OVER THE NORTH
CAROLINA COASTAL WATERS THIS MORNING AHEAD OF APPROACHING COLD
FRONT. SPEEDS ARE 10 KNOTS OR LESS AND SEAS 4 TO 6 FEET. SMALL CRAFT
ADVISORY IS IN EFFECT. WINDS WILL INCREASE ASSOCIATED WITH THE COLD
FRONTAL PASSAGE IN THE EARLY AFTERNOON HOURS. WIND WIND SHIFT TO
NORTHERLY BEHIND THE FRONT.
STILL APPEARS THAT THERE WILL BE SEVERAL HOURS LATER THIS
EVENING/TONIGHT WHERE SEAS DROP TO BELOW 6 FEET...BUT WILL CONTINUE
SMALL CRAFT ADVISORY INTO LATE WEEK...AS GUSTY N/NW WINDS WILL
DEVELOP ON THE BACKSIDE OF THE STRENGTHENING LOW OFF THE NC COAST
LATER TONIGHT WITH SEAS...PER LATEST LOCAL NWPS/SWAN
MODEL...BUILDING TO 6 TO 9 FEET OVER THE NORTHERN WATERS AND AROUND
6 FEET SOUTHERN WATERS AFTER MIDNIGHT.
LONG TERM /WEDNESDAY THROUGH SUNDAY/...
ACTIVE MARINE WEATHER EARLY THIS FORECAST PERIOD AS DEEPENING SFC
LOW PRES SKIRTS THE COAST. MAY SEE SOME GALE FORCE WINDS, MAINLY IN
GUSTS OVER THE NORTHERN AND CENTRAL COASTAL WATERS AS THE
INTENSIFYING LOW MOVES NE OF THE AREA WEDNESDAY. SOLID SMALL CRAFT
ADVISORY LEVEL WINDS LIKELY CONTINUE WED NIGHT THRU THURSDAY BEFORE
BEGINNING TO DIMINISH AS HIGH PRESSURE BUILDS EAST ON FRIDAY. SEAS
PEAK 10-12 FT WEDNESDAY THEN SLOWLY SUBSIDE BUT MAY REMAIN ABV 6 FT
OVER THE OUTER COASTAL WATERS THRU FRIDAY.
WINDS SHIFT W/SW AND GRADUALLY INCREASE AGAIN AS HIGH PRESSURE MOVES
OFFSHORE DURING THE WEEKEND. SW WINDS MAY AGAIN BEGIN TO APPROACH
SMALL CRAFT ADVISORY LEVELS ON SUNDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST WEDNESDAY FOR
AMZ130-135.
SMALL CRAFT ADVISORY UNTIL 4 PM EST THURSDAY FOR AMZ150-152-
154-156-158.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CGG
SHORT TERM...CTC
LONG TERM...BTC
AVIATION...CTC/BTC
MARINE...CGG/CTC/BTC
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
659 PM CST WED NOV 26 2014
.UPDATE...
ISSUED AT 656 PM CST WED NOV 26 2014
NW TO SE ORIENTATED UPPER LEVEL JET WAS WEST OF THE FORECAST AREA
AND WILL SHIFT OVER THE RED RIVER VALLEY BY MORNING. PRECIPITABLE
WATER WAS UNDER ONE TENTH OF AN INCH AND WILL INCREASE SLIGHTLY IN
THE WESTERN ZONES BY MORNING. HIGH PRESSURE WAS LOCATED JUST WEST
OF THE RED RIVER. TEMPS ALREADY BELOW ZERO OVER ALL BUT THE FAR
SOUTHEAST ZONES. TWEAKED WINDS A BIT FOR TONIGHT. NO OTHER CHANGES
MADE AT THIS TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 328 PM CST WED NOV 26 2014
FORECAST CHALLENGE FOR THE SHORT TERM WILL BE OVERNIGHT LOWS
TONIGHT AS WELL AS TIMING AND AMOUNT OF SNOW THANKSGIVING NIGHT. A
SURFACE HIGH WILL DROP INTO THE VALLEY TONIGHT AND BRING A VERY
COLD AND DRY AIR MASS. THIS WILL RESULT IN OVERNIGHT LOWS WELL
BELOW SEASONAL NORMS. A CLIPPER THEN MOVES INTO EASTERN MONTANA
TOMORROW NIGHT AND A BAND OF SNOW IS EXPECTED TO FORM OVER
PORTIONS OF CENTRAL AND EASTERN NORTH DAKOTA ON INTO NORTHWEST
MINNESOTA. HAVE USED A BLEND OF NAM DNG AND HRRR FOR OVERNIGHT
LOWS TONIGHT AND A MODEL BLEND FOR THE THANKSGIVING NIGHT SYSTEM
AS THERE ARE STILL VARIATIONS ON THE PLACEMENT OF SNOW.
TONIGHT...CURRENT VIS SATELLITE SHOWS CLEARING LINE HAS MADE IT AS
FAR SOUTH OF I 94. DEW POINTS NORTH OF THIS MID CLOUD DECK ARE
ALREADY 5 TO 10 BELOW AND IN THE MID TEENS BELOW ACROSS SOUTHERN
MANITOBA. THE RIDGE AXIS EXTENDING OUT OF A HIGH OVER MANITOBA WILL
BRING CALM WINDS TO THE DVL REGION EARLY IN THE EVENING...AND WITH
A LIGHT COVERING OF FRESH SNOW THE TEMPS SHOULD QUICKLY DROP TO 5
TO 10 BELOW THIS EVENING. BY MORNING...RETURN FLOW SETS UP OVER
THE DEVILS LAKE BASIN REGION UP THROUGH
TOWNER/PEMBINA/CAVALIER COUNTIES. THIS WILL ALLOW WIND CHILLS TO
DROP INTO THE 20 TO 25 BELOW RANGE TONIGHT...AND EVENING SHIFT
WILL NEED TO MONITOR CLOSELY AS COLDER TEMPS WOULD BRING AREA INTO
WIND CHILL ADVISORY CRITERIA (LESS THAN 25 BELOW ZERO). WARMEST
TEMPS SHOULD BE ACROSS THE FAR SOUTH AS THE CURRENT MID CLOUDS
WILL DELAY RADIATIONAL COOLING FOR AT LEAST A FEW HOURS THIS
EVENING...BUT EXPECT THAT AREA TO CLEAR OUT BY 02Z TO 03Z. DEW
POINTS ARE ABOUT 10 DEG HIGHER IN THIS REGION SO NOT LOOKING FOR
AS SIGNIFICANT OF A DROP OFF. RIDGE AXIS SHOULD THEN BE OVER THE
EAST TOMORROW MORNING AND TEMPS SHOULD DROP TO AROUND 10 BELOW.
TOMORROW AND TOMORROW NIGHT...A VERY COLD START TO THE DAY WILL LIMIT
DAYTIME HIGHS DESPITE SOME SOLAR IN THE MORNING BEFORE WE SEE
INCREASING CLOUDS FROM WEST TO EAST TOMORROW AFTERNOON. TEMPS WILL
STRUGGLE TO BREAK 10 ABOVE. BAND OF SNOW ASSOCIATED WITH WARM
ADVECTION AND ISENTROPIC LIFT WILL SET UP OVER WESTERN ND TOMORROW
MORNING AND MOVE INTO CNTRL ND IN THE AFTN. A BAND OF ISENTROPIC
LIFT INTENSIFIES AND MOVES INTO THE WESTERN CWA BETWEEN 00Z AND
06Z. NAM 280K ISENTROPIC SFC WINDS IN THE 20 TO 30 KT RANGE ARE
DIRECTLY PERPENDICULAR TO THE PRESSURE GRADIENT AND SHOULD BE
SUFFICIENT TO LIFT THE PARCEL ABOUT 100 MB...WITH NEARLY SATURATED
CONDENSATION PRESSURE DEFICITS IN EASTERN NORTH DAKOTA. THERE IS
STILL DIFFERENCES IN THE PLACEMENT OF THE SNOW...WITH ECMWF A BIT
FURTHER SOUTH AND WEST THAN THE 18Z NAM AND 12Z GFS. HPC QPF
GUIDANCE PREFERS THE SLIGHTLY NORTHWARD SOLUTION...AND HAVE
UPDATED SNOW RATIOS TO YIELD 3 TO 4 INCHES IN NORTH OF THE DEVILS
LAKE REGION DOWN THROUGH THE CENTRAL VALLEY.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 328 PM CST WED NOV 26 2014
FRIDAY...SNOW SHOULD BEGIN TAPERING OFF FRIDAY MORNING BUT
PORTIONS OF EASTERN NORTH DAKOTA TO INCLUDE THE NORTHERN VALLEY
WILL HAVE ANOTHER TWO TO FOUR INCHES OF SNOW. MOTORISTS IN
NORTHEASTERN NORTH DAKOTA CAN EXPECT LESS THAN DESIRABLE DRIVING
CONDITIONS FOR BLACK FRIDAY SHOPPING...ESPECIALLY IN THE EARLY
MORNING HOURS. ANOTHER SFC LOW ENTERS EASTERN MT FRI AFTN AND
MOVES INTO THE DAKOTAS OVERNIGHT. MODELS CONTINUING TO DIFFER ON
QPF AMOUNTS AND PLACEMENT OF THIS SECOND SHOT OF SNOW. GFS IS THE
MOST BULLISH AND BRINGS SOUTHERN EDGE OF SNOW BAND DOWN TO THE
HIGHWAY 2 CORRIDOR WHILE THE NAME IS FAIRLY DRY AND THE ECMWF
KEEPS SNOW MAINLY NORTH OF INTL BORDER. DO TO MODEL INCONSISTENCY
WILL USE CONTINUITY AS SOLUTION...WITH LOW CHANCE POPS ACROSS THE
NORTHERN TIER OF COUNTIES. WILL LIKELY SEE A BREAK MID DAY BETWEEN
THE TWO SNOW PRODUCING SYSTEMS SHOULD THE SNOW SET UP ALONG AND
NORTH OF HWY 200...THE MOST LIKELY AREA FOR ADDITIONAL
ACCUMULATION. DAYTIME HIGHS WILL BE WARMER ON FRIDAY AND JUMP
INTO THE MID 20S ACROSS THE SOUTH.
SATURDAY...GFS/ECMWF CONTINUE TO SHOW LINGERING SNOW SHOWERS
ACROSS THE NORTH AS NW SFC FLOW SETS UP...WHILE THE NAM REMAINS
DRY. WILL KEEP CONTINUITY FOR THIS PERIOD AS WELL...ALTHOUGH ANY
SNOW ON SATURDAY SHOULD BE LIGHT WITH LITTLE ACCUMULATION.
SATURDAY NIGHT THROUGH WEDNESDAY...MODELS START OUT IN FAIRLY DECENT
AGREEMENT...PUSHING A POSITIVELY TILTED TROUGH THROUGH THE NORTHERN
ROCKIES AND PLAINS OVER THE WEEKEND. THE COLD FRONT WILL MOVE
THROUGH THE CWA SATURDAY NIGHT AND COLD HIGH PRESSURE WILL BE IN
PLACE FOR SUNDAY. CONTINUED TO KEEP SOME 30ISH POPS FOR WHEN THE
FRONTAL BOUNDARY PASSES...THEN DRYING OUT INTO THE EARLY PART OF THE
WORK WEEK. TEMPS WILL AGAIN BE WELL BELOW AVERAGE WITH LOWS IN THE
TEENS BELOW ZERO AND HIGHS IN THE SINGLE DIGITS ABOVE FOR SUNDAY AND
MONDAY.
MODEL CONSENSUS STARTS TO DIVERGE BY TUESDAY AND WEDNESDAY. THE GFS
IS MORE ACTIVE AND BRING A VIGOROUS SHORTWAVE THROUGH THE NORTHERN
PLAINS WITH SFC LOW PRESSURE JUST TO OUR NORTH AND THE CWA SHOWING
SOME STRONG WARM AIR ADVECTION MONDAY AND EARLY TUESDAY BEFORE THE
NEXT COLD FRONT COMES IN. THE ECMWF IS WEAKER AND DRIER. ENSEMBLE
MEMBERS SHOW A GOOD AMOUNT OF SPREAD...SO FOR NOW KEPT ONLY MINIMAL
POPS AS THE OPERATIONAL GFS IS ONE OF THE WETTER SOLUTIONS. TEMPS
SHOULD SEE SOME WARMING ON TUESDAY AND COLDER AGAIN ON
WEDNESDAY...BUT EVEN THE HIGHER TEMP DAYS WILL STILL BE BELOW
SEASONAL AVERAGES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 656 PM CST WED NOV 26 2014
VFR CONDITIONS ARE ACROSS THE AREA AND EXPECT VFR CONDITIONS TONIGHT
AND THU. CIRRUS CLOUDS SHOULD MOVE IN AFTER MIDNIGHT AND CIGS SHOULD
LOWER TO AROUND 10 THOUSAND FT IN EASTERN ND...HIGHER IN THE EASTERN
ZONES THU AFTERNOON.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...HOPPES
SHORT TERM...SPEICHER
LONG TERM...JR/SPEICHER
AVIATION...HOPPES
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1244 PM CST TUE NOV 25 2014
.UPDATE...
ISSUED AT 1233 PM CST TUE NOV 25 2014
AT 12 NOON CST IR SAT AND RUC MODEL SHOW THE VORT CENTER PAST
WILLISTON AND MOVING SOUTHEAST. SNOW SHOULD BE QUIT A BIT LIGHTER
ACROSS THE NORTHWEST NOW. THE FOCUS FOR MODERATE SNOW FOR THE NEXT
2 TO 3 HOURS WILL BE FROM STANLEY SOUTHEAST TO BISMARCK. STARTING
TO SEE GUSTY WINDS ACROSS EASTERN MONTANA. WITH TEMPERATURES IN
THE MID 30S SOUTHWEST FOR HIGHS TODAY MAY BE A PROBLEM GETTING
MUCH BLOWING SNOW INITIALLY. AS TEMPERATURES FALL ROADS WILL
BECOME SLICK THERE. WILL CONTINUE THE ADVISORY UNTIL THE BLOWING
SNOW ISSUES ARE RESOLVED.
UPDATE ISSUED AT 928 AM CST TUE NOV 25 2014
IR SATELLITE LOOPS SHOW VORT MAX JUST NORTHWEST OF WILLISTON MOVING
SOUTHEAST AS RUC13 MODEL SHOWS. TRACK OF THIS VORT SHOULD DEFINE
THE HEAVIEST SNOW BAND FOR THE REMAINING MORNING HOURS FROM
WILLISTON TO GARRISON AND NORTH. LIGHTER SNOW SOUTHWEST OF THIS
LINE. WILLISTON SHOWING ONE HALF MILE VSBY IN MODERATE SNOW AT 9
AM CST. SNOW RATES SHOULD BEGIN TO LIGHTEN NORTHWEST ND AS THE
VORT LOBE MOVES PAST LATE THIS AM.
UPDATE ISSUED AT 630 AM CST TUE NOV 25 2014
FORECAST IS ON TRACK. REGIONAL RADARS SHOWS AREA OF SNOW MOVING
INTO EASTERN MONTANA WITH THE MOST RECENT BAKER OB REPORTING SNOW.
CEILINGS CONTINUE TO LOWER ACROSS WESTERN ND LOCATIONS AND
MARMARTH ND DOT WEB CAM NOW SHOWS SNOWFALL OCCURRING. BOWMAN RADAR
ALSO SHOWS STRONGER ECHOES ACROSS THE SOUTHWEST. ONLY CHANGES WERE
TO BLEND FORECAST TO MOST RECENT OBSERVATIONS...OTHERWISE EXPECT
SNOW TO CONTINUE EXPANDING EASTWARD THROUGH THE MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CST TUE NOV 25 2014
HIGHLIGHTS INCLUDE A WINTER WEATHER ADVISORY TO BE ISSUED FOR SNOW
AMOUNTS TODAY AND TONIGHT AND GUSTY WINDS TONIGHT.
THE FORECAST CHALLENGE IN THE SHORT TERM WILL BE SNOW AMOUNTS TODAY
AND TONIGHT.
CURRENTLY A SURFACE LOW PRESSURE CENTER WAS OVER SOUTHERN ALBERTA.
AT UPPER LEVELS A FAST-MOVING SHORTWAVE IN THE NORTHWEST FLOW ALOFT
WAS COINCIDENT WITH THE SURFACE LOW. AS THE SHORTWAVE DIVES
SOUTHEAST ACROSS THE DAKOTAS TODAY AND INTO THIS EVENING...THE
SURFACE LOW/CLIPPER WILL ALSO TRACK SOUTHEAST QUICKLY ACROSS THE
REGION. THIS SCENARIO WILL CREATE A STRONG BAROCLINIC ZONE ORIENTED
NORTHWEST-TO-SOUTHEAST ACROSS NORTH DAKOTA. AS THE SYSTEM TRACKS
ACROSS THE STATE...THE BEST LIFT/INSTABILITY WILL BE ALONG AND
NORTHEAST OF THE SURFACE LOW TRACK. MEANWHILE SOUTHWEST OF THE LOW
TRACK (SOUTHWESTERN QUARTER OF ND) WILL BE IN THE WARM SECTOR OF THE
SYSTEM...AND SURFACE TEMPERATURES SHOULD REACH INTO THE LOWER 30S
THERE TODAY. THUS THE SOUTHWEST WILL SEE A RAIN/SNOW MIX...WHILE
LIGHT TO MODERATE SNOW WILL OCCUR ACROSS NORTHWESTERN AND CENTRAL
NORTH DAKOTA.
THE SNOW IS EXPECTED TO BEGIN BEFORE DAYBREAK IN THE FAR
WEST...BECOME MORE INTENSE WITH TIME AS THE FAVORED SNOW BANDS
APPROACH CENTRAL NORTH DAKOTA CLOSER TO NOON...AND CONTINUE THIS
EVENING OVER CENTRAL/EASTERN NORTH DAKOTA. CURRENT MODEL RUNS ARE IN
BETTER AGREEMENT FOR PLACEMENT AND TIMING. THUS EXPECTING 3-4 INCHES
OF SNOW IN AN ARC/LINE FROM CROSBY IN THE FAR NORTHWEST...TO
STANLEY/MINOT/BOTTINEAU TO BISMARCK/JAMESTOWN AND LINTON/OAKES.
AROUND 1.5 TO 2.5 INCHES OF SNOW IS FORECAST FOR MAINLY SOUTH AND
WEST OF THE MISSOURI RIVER...AND IN THE TURTLE MOUNTAINS AREA.
IN ADDITION TO THE SNOW...NORTHWEST WINDS ARE FORECAST TO INCREASE
TO 20 TO 25 MPH THIS AFTERNOON AND EVENING IN THE SOUTHWEST AND INTO
CENTRAL NORTH DAKOTA. ALTHOUGH BLOWING SNOW IS NOT EXPECTED BECAUSE
OF THE FAIRLY WET NATURE OF THE FALLING SNOW...DRIFTING SNOW ACROSS
ROADWAYS COMBINED WITH SNOW-COVERED AND ICY ROADS WILL MAKE FOR
HAZARDOUS TRAVEL.
DECIDED TO ISSUE A WINTER WEATHER ADVISORY FOR ALL OF WESTERN AND
CENTRAL NORTH DAKOTA. BEGAN THE ADVISORY IN THE WESTERN QUARTER OF
THE STATE THIS MORNING AND ENDED IT THERE AROUND MIDNIGHT TONIGHT.
BEGAN THE ADVISORY FOR CENTRAL NORTH DAKOTA THIS AFTERNOON AND WILL
HAVE IT VALID UNTIL JUST BEFORE SUNRISE WEDNESDAY MORNING...WHEN
WINDS SHOULD BE DECREASING AND SNOW TAPERING TO FLURRIES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM CST TUE NOV 25 2014
MAIN FORECAST CHALLENGES INVOLVE PERIODIC CHANCES OF PRECIPITATION
AS ACTIVE PATTERN CONTINUES. ON WEDNESDAY...THE STORM SYSTEM WILL
DEPART TO THE SOUTHEAST WITH 1038MB SURFACE HIGH DROPPING
SOUTHWARD ACROSS THE NORTHERN PLAINS. WILL MAINTAIN LOW CHANCE
POPS FOR SNOW ACROSS SOUTHWEST PORTION OF STATE CLOSEST TO SURFACE
LOW/FRONTAL BOUNDARY IN MONTANA. NEXT SYSTEM AFFECTS OUR AREA ON
THURSDAY WITH SURFACE LOW SUPPORTED BY 120KT 300MB JET STREAK
NUDGING IN FROM MONTANA. SNOW TOTALS WITH THIS SYSTEM SHOULD BE IN
THE 1 TO 3 INCH RANGE WITH HIGHEST AMOUNTS EXPECTED ACROSS THE
NORTH NEAR CANADIAN BORDER AND ABOUT 1 TO 2 INCHES ALONG THE I-94
CORRIDOR. MODELS CONTINUE TO INDICATE WARM POCKET ALOFT BEHIND
MAIN BAND OF PRECIP...SO WILL HAVE TO CONTINUE TO MONITOR FOR
POSSIBILITY OF MIX PRECIP TYPE DEVELOPING. ANOTHER SYSTEM MOVES
THROUGH THE AREA FRIDAY/FRIDAY NIGHT WITH A CONTINUED CHANCE OF
LIGHT SNOW...MAINLY NORTH. THIS SYSTEM WILL ALSO PULL ANOTHER SHOT
OF ARCTIC AIR SOUTHWARD RESULTING IN WIND CHILLS IN THE -25 TO
-30F RANGE ACROSS THE NORTH SATURDAY NIGHT AND SUNDAY MORNING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1233 PM CST TUE NOV 25 2014
SURFACE LOW PRESSURE WILL TRACK FROM NORTHWEST NORTH DAKOTA
SOUTHEAST INTO SOUTH DAKOTA TONIGHT. THE LOW WILL BE THE FOCUS
FOR SNOW AND IFR CONDITIONS SPREADING THROUGH WEST AND CENTRAL
NORTH DAKOTA TODAY. GUSTY WINDS TO 35 KTS POSSIBLE SOUTHWEST THIS
AFTERNOON AND EVENING. CONDITIONS IMPROVING TO MVFR WESTERN ND
TONIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM CST /5 AM MST/ WEDNESDAY FOR
NDZ003>005-011>013-019>023-025-034>037-042-045>048-050-051.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT
FOR NDZ001-002-009-010-017-018-031>033-040-041-043-044.
&&
$$
UPDATE...WAA
SHORT TERM...JV
LONG TERM...JNS
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
941 AM CST TUE NOV 25 2014
.UPDATE...
ISSUED AT 928 AM CST TUE NOV 25 2014
IR SATELLITE LOOPS SHOW VORT MAX JUST NORTHWEST OF WILLISTON MOVING
SOUTHEAST AS RUC13 MODEL SHOWS. TRACK OF THIS VORT SHOULD DEFINE
THE HEAVIEST SNOW BAND FOR THE REMAINING MORNING HOURS FROM
WILLISTON TO GARRISON AND NORTH. LIGHTER SNOW SOUTHWEST OF THIS
LINE. WILLISTON SHOWING ONE HALF MILE VSBY IN MODERATE SNOW AT 9
AM CST. SNOW RATES SHOULD BEGIN TO LIGHTEN NORTHWEST ND AS THE
VORT LOBE MOVES PAST LATE THIS AM.
UPDATE ISSUED AT 630 AM CST TUE NOV 25 2014
FORECAST IS ON TRACK. REGIONAL RADARS SHOWS AREA OF SNOW MOVING
INTO EASTERN MONTANA WITH THE MOST RECENT BAKER OB REPORTING SNOW.
CEILINGS CONTINUE TO LOWER ACROSS WESTERN ND LOCATIONS AND
MARMARTH ND DOT WEB CAM NOW SHOWS SNOWFALL OCCURRING. BOWMAN RADAR
ALSO SHOWS STRONGER ECHOES ACROSS THE SOUTHWEST. ONLY CHANGES WERE
TO BLEND FORECAST TO MOST RECENT OBSERVATIONS...OTHERWISE EXPECT
SNOW TO CONTINUE EXPANDING EASTWARD THROUGH THE MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CST TUE NOV 25 2014
HIGHLIGHTS INCLUDE A WINTER WEATHER ADVISORY TO BE ISSUED FOR SNOW
AMOUNTS TODAY AND TONIGHT AND GUSTY WINDS TONIGHT.
THE FORECAST CHALLENGE IN THE SHORT TERM WILL BE SNOW AMOUNTS TODAY
AND TONIGHT.
CURRENTLY A SURFACE LOW PRESSURE CENTER WAS OVER SOUTHERN ALBERTA.
AT UPPER LEVELS A FAST-MOVING SHORTWAVE IN THE NORTHWEST FLOW ALOFT
WAS COINCIDENT WITH THE SURFACE LOW. AS THE SHORTWAVE DIVES
SOUTHEAST ACROSS THE DAKOTAS TODAY AND INTO THIS EVENING...THE
SURFACE LOW/CLIPPER WILL ALSO TRACK SOUTHEAST QUICKLY ACROSS THE
REGION. THIS SCENARIO WILL CREATE A STRONG BAROCLINIC ZONE ORIENTED
NORTHWEST-TO-SOUTHEAST ACROSS NORTH DAKOTA. AS THE SYSTEM TRACKS
ACROSS THE STATE...THE BEST LIFT/INSTABILITY WILL BE ALONG AND
NORTHEAST OF THE SURFACE LOW TRACK. MEANWHILE SOUTHWEST OF THE LOW
TRACK (SOUTHWESTERN QUARTER OF ND) WILL BE IN THE WARM SECTOR OF THE
SYSTEM...AND SURFACE TEMPERATURES SHOULD REACH INTO THE LOWER 30S
THERE TODAY. THUS THE SOUTHWEST WILL SEE A RAIN/SNOW MIX...WHILE
LIGHT TO MODERATE SNOW WILL OCCUR ACROSS NORTHWESTERN AND CENTRAL
NORTH DAKOTA.
THE SNOW IS EXPECTED TO BEGIN BEFORE DAYBREAK IN THE FAR
WEST...BECOME MORE INTENSE WITH TIME AS THE FAVORED SNOW BANDS
APPROACH CENTRAL NORTH DAKOTA CLOSER TO NOON...AND CONTINUE THIS
EVENING OVER CENTRAL/EASTERN NORTH DAKOTA. CURRENT MODEL RUNS ARE IN
BETTER AGREEMENT FOR PLACEMENT AND TIMING. THUS EXPECTING 3-4 INCHES
OF SNOW IN AN ARC/LINE FROM CROSBY IN THE FAR NORTHWEST...TO
STANLEY/MINOT/BOTTINEAU TO BISMARCK/JAMESTOWN AND LINTON/OAKES.
AROUND 1.5 TO 2.5 INCHES OF SNOW IS FORECAST FOR MAINLY SOUTH AND
WEST OF THE MISSOURI RIVER...AND IN THE TURTLE MOUNTAINS AREA.
IN ADDITION TO THE SNOW...NORTHWEST WINDS ARE FORECAST TO INCREASE
TO 20 TO 25 MPH THIS AFTERNOON AND EVENING IN THE SOUTHWEST AND INTO
CENTRAL NORTH DAKOTA. ALTHOUGH BLOWING SNOW IS NOT EXPECTED BECAUSE
OF THE FAIRLY WET NATURE OF THE FALLING SNOW...DRIFTING SNOW ACROSS
ROADWAYS COMBINED WITH SNOW-COVERED AND ICY ROADS WILL MAKE FOR
HAZARDOUS TRAVEL.
DECIDED TO ISSUE A WINTER WEATHER ADVISORY FOR ALL OF WESTERN AND
CENTRAL NORTH DAKOTA. BEGAN THE ADVISORY IN THE WESTERN QUARTER OF
THE STATE THIS MORNING AND ENDED IT THERE AROUND MIDNIGHT TONIGHT.
BEGAN THE ADVISORY FOR CENTRAL NORTH DAKOTA THIS AFTERNOON AND WILL
HAVE IT VALID UNTIL JUST BEFORE SUNRISE WEDNESDAY MORNING...WHEN
WINDS SHOULD BE DECREASING AND SNOW TAPERING TO FLURRIES.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM CST TUE NOV 25 2014
MAIN FORECAST CHALLENGES INVOLVE PERIODIC CHANCES OF PRECIPITATION
AS ACTIVE PATTERN CONTINUES. ON WEDNESDAY...THE STORM SYSTEM WILL
DEPART TO THE SOUTHEAST WITH 1038MB SURFACE HIGH DROPPING
SOUTHWARD ACROSS THE NORTHERN PLAINS. WILL MAINTAIN LOW CHANCE
POPS FOR SNOW ACROSS SOUTHWEST PORTION OF STATE CLOSEST TO SURFACE
LOW/FRONTAL BOUNDARY IN MONTANA. NEXT SYSTEM AFFECTS OUR AREA ON
THURSDAY WITH SURFACE LOW SUPPORTED BY 120KT 300MB JET STREAK
NUDGING IN FROM MONTANA. SNOW TOTALS WITH THIS SYSTEM SHOULD BE IN
THE 1 TO 3 INCH RANGE WITH HIGHEST AMOUNTS EXPECTED ACROSS THE
NORTH NEAR CANADIAN BORDER AND ABOUT 1 TO 2 INCHES ALONG THE I-94
CORRIDOR. MODELS CONTINUE TO INDICATE WARM POCKET ALOFT BEHIND
MAIN BAND OF PRECIP...SO WILL HAVE TO CONTINUE TO MONITOR FOR
POSSIBILITY OF MIX PRECIP TYPE DEVELOPING. ANOTHER SYSTEM MOVES
THROUGH THE AREA FRIDAY/FRIDAY NIGHT WITH A CONTINUED CHANCE OF
LIGHT SNOW...MAINLY NORTH. THIS SYSTEM WILL ALSO PULL ANOTHER SHOT
OF ARCTIC AIR SOUTHWARD RESULTING IN WIND CHILLS IN THE -25 TO
-30F RANGE ACROSS THE NORTH SATURDAY NIGHT AND SUNDAY MORNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY AFTERNOON)
ISSUED AT 928 AM CST TUE NOV 25 2014
SURFACE LOW PRESSURE WILL TRACK FROM NORTHEAST MONTANA THROUGH
WESTERN NORTH DAKOTA TODAY. THE LOW WILL BE THE FOCUS FOR SNOW AND
IFR CONDITIONS SPREADING THROUGH WEST AND CENTRAL NORTH DAKOTA
TODAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM CST /5 AM MST/ WEDNESDAY FOR
NDZ003>005-011>013-019>023-025-034>037-042-045>048-050-051.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST /11 PM MST/ TONIGHT
FOR NDZ001-002-009-010-017-018-031>033-040-041-043-044.
&&
$$
UPDATE...WAA
SHORT TERM...JV
LONG TERM...JNS
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1112 PM CST MON NOV 24 2014
.UPDATE...
ISSUED AT 933 PM CST MON NOV 24 2014
SO ONLY -SN OR FLURRIES BE REPORTED BY UPSTREAM OBSERVATIONS. NO
ACCUMULATION EXPECTED...AND IF FREEZING DRIZZLE DOES OCCUR (AS THE
DRY LAYER ALOFT MOVES OVER THE REGION) IT SHOULD BE VERY LIGHT AND
PATCHY AND LIKELY WILL NOT CAUSE ANY PROBLEMS (THIS IS FOR THE
DEVILS LAKE BASIN AND SOUTHWARD).
UPDATE ISSUED AT 656 PM CST MON NOV 24 2014
WEAK UPPER SHORTWAVE PRODUCING RADAR RETURNS ACROSS SOUTHWEST
MANITOBA INTO NORTH CENTRAL AND NORTHWEST NORTH DAKOTA. A FEW OB
SITES INDICATING -SN WITH VSBY IN THE 2SM-5SM RANGE. WILL KEEP THE
SCHC POPS FOR LATER THIS EVENING INTO THE OVERNIGHT HOURS FOR THE
FAR WESTERN FA. THE RAP AND HRRR ALSO INDICATE QPF HERE...ALBEIT
VERY LIGHT. THE MAIN CONCERN WITH THIS QPF IS THAT A DRY LAYER
ALOFT WILL BE MOVING INTO THIS REGION AFTER MIDNIGHT...AND WITH
THE LOW-LEVEL MOIST LAYER MEAN TEMPERATURES AROUND -5C TO
-8C...SUPERCOOLED WATER DROPLETS ARE POSSIBLE. INSERTED PATCHY
FREEZING DRIZZLE INTO THE FORECAST FOR THE DEVILS LAKE BASIN AND
SOUTHWARD.
WILL ALSO ISSUE A SPS FOR THE SNOWFALL POTENTIAL TUESDAY
EVENING/OVERNIGHT. WFO BIS HAS A STATEMENT ISSUED...AND IT WOULD
BE BEST TO KEEP THE MESSAGE WITHIN NORTH DAKOTA CONSISTENT.
PLUS...A FEW INDICATIONS FOR MESO-SCALE BANDING (STEEP MID-LEVEL
LAPSE RATE...FRONTOGENESIS...POSSIBLE CONDITIONAL
INSTABILITY)...AND HIGHER RESOLUTION MODELS INDICATING A NARROW
BAND OF QPF UP TO AROUND 0.4 INCHES (SO COULD BE A NARROW BAND OF
3-5 INCHES...BUT LOCATION OF THIS BAND COULD BE ANYWHERE).
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 333 PM CST MON NOV 24 2014
FCST CHALLENGE IS LOW TEMPS TONIGHT AND THEN SNOW THREAT TUESDAY
NIGHT. FOR TONIGHT...SKIES GENERALLY CLEAR OVER MUCH OF ERN/CNTRL
ND WITH LINGERING CLOUDS ROUGHLY ROSEAU TO FARGO TO FORMAN EAST.
CLOUDS IN THE EAST WILL SLOWLY DIMINISH AS LOW PRESSURE MOVES
INTO UPPER MICHIGAN. EXPECT A PERIOD OF CLEAR SKY THIS EVENING IN
ERN ND AND AS WINDS LIGHTEN TEMPS COULD FALL QUICKLY IN SOME
SPOTS. VARIABLE SNOW COVER WILL MAKE LOW TEMPS TOUGH...BUT
GENERALLY EXPECT SINGLE DIGITS. THERE IS A SHORT WAVE IN
SASKATCHEWAN THAT WILL MOVE SOUTHEAST. THERE HAS BEEN SOME VERY
LIGHT WITH THIS ON CANADIAN RADAR BUT MODELS INDICATE PRECIP WILL
DRY OUT MORE AS IT MOVES EAST INTO SFC HIGH. DID KEEP 20 POP FOR
ANY LIGHT SNOW THAT MAY MAKE IT INTO WRN FCST AREA TOWARD MIDNIGHT
OR A BIT AFTER. CLOUDS COMING INTO THE WEST SHOULD MAKE TEMP FALL
STOP AND TEMPS RISE A BIT.
ALBERTA CLIPPER SYSTEM FOR LATER TUESDAY HANDLED A BIT BETTER NOW
WITH CONSENSUS IS TO TAKE SFC LOW THRU SOUTHWESTERN ND INTO
EASTERN SD WITH BAND OF 2-3 INCH SNOWFALL WILLISTON TO CARRINGTON
TO ABOUT WAHPETON-FORMAN AREA. LESSER AMOUNTS EAST OF THIS BUT
STILL EXPECT ENOUGH MOISTURE INTO THE COLDER AIRMASS NORTHEAST OF
THE LOW TO SQUEEZE OUT SOME LIGHT SNOW TUES NIGHT. LOOK FOR A
PERIOD OF WIND (20-25 KTS) SRN VALLEY LATE TUES NIGHT SO WILL NEED
TO WATCH THAT FOR ANY BLOWING SNOW ISSUES IF FORECAST PANS OUT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 333 PM CST MON NOV 24 2014
BLUSTERY AND COLD WEDNESDAY AS HIGH DROPS SOUTH. NEXT SHORT WAVE
DUE TO MOVE EAST FROM SOUTHERN B.C. INTO MONTANA AND NORTHWESTERN
NORTH DAKOTA THANKSGIVING DAY WITH LIGHT SNOW REACHING DVL BASIN
THURSDAY LATE AFTN. THIS IS A MORE PACIFIC HYBRID TYPE SYSTEM AND
MODELS TYPICALLY HAVE A HARD TIME WITH THESE AND WITH THERMAL
BOUNDARY IN PLACE TRACK OF SYSTEM MAY CHANGE.
THURSDAY NIGHT TO MONDAY...MODELS IN FAIR AGREEMENT WITH THE LONG
HOLIDAY WEEKEND WEATHER. CHC OF SNOW THURSDAY NIGHT THROUGH SATURDAY
NIGHT AS 500MB FLOW BECOMES NEARLY ZONAL AND A BAROCLINIC ZONE SETS
UP ACROSS THE NORTHERN PLAINS. BEST CHC WILL BE THURSDAY NIGHT
ACROSS THE ENTIRE CWFA AS WAA OCCURS AND TEMPS RISE OVERNIGHT.
LESSER CHCS CONTINUING INTO THE WEEKEND ESPECIALLY ACROSS THE
NORTHERN TIER. THE BAROCLINIC ZONE WILL BE PUSHED SOUTH OF THE AREA
AS 1036MB HIGH PRESSURE MOVES INTO THE REGION SUNDAY...ENDING THE
PCPN THREAT. MAX TEMPS WILL BE BLO END OF NOVEMBER NORMALS WITH 20S
FRI FALLING INTO THE TEENS AND SINGLE DIGITS SATURDAY THROUGH
MONDAY WITH SUNDAY BEING THE COLDEST DAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1112 PM CST MON NOV 24 2014
AN AREA OF MVFR CIGS IS APPROACHING THE REGION FROM THE
NORTHWEST...AND SHOULD AFFECT ALL TAF SITES EVENTUALLY. THESE
CIGS WILL LIKELY CONTINUE THROUGH MUCH OF THE DAY ON TUESDAY. -SN
EXPECTED TO AFFECT KDVL/KGFK/KFAR TUESDAY EVENING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...RIDDLE
LONG TERM...RIDDLE
AVIATION...TG
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
208 PM MST TUE NOV 25 2014
.SHORT TERM...THIS EVENING THROUGH WEDNESDAY NIGHT
ISSUED AT 205 PM MST TUE NOV 25 2014
THE LATEST WATER VAPOR IMAGES AND RAP ANALYSES INDICATED A LARGE
TROUGH OVER THE CNTRL/ERN CONUS WITH A RIDGE OVER THE WEST COAST.
A POTENT SHORT-WAVE TROUGH WAS MOVING ACROSS ERN MT INTO NWRN
SD...AIDED BY A 150-KT UPPER JET. SCT RAIN/SNOW SHOWERS WERE
ACROSS MUCH OF WRN SD AND NERN WY...BUT WITH A DOWNSLOPE HOLE OVER
PARTS OF SWRN SD. AREA WEBCAMS SHOWED AROUND ONE INCH OF SNOW OVER
NERN WY...A TRACE OVER NWRN SD...AND 1-2 INCHES IN THE NRN BLKHLS.
A SFC LOW OVER WRN ND WAS ASSOCIATED WITH 2-5MB/3HR PRES RISES AS
IT MOVED SOUTHEAST...WITH NORTHWEST WINDS OF 20-35 MPH BEHIND THE
LOW MOVING INTO NWRN SD.
THERE IS DECENT MODEL AGREEMENT IN THE SHORT TERM THROUGH AT LEAST
12Z THU. HEIGHTS WILL BE RISING THROUGH THE PERIOD WITH THICKNESSES
RISING WED THROUGH THU. FOR TNGT...THE SHORT-WAVE TROUGH MOVES TO
NERN KS AS THE SFC LOW MOVES TO SWRN IA. THIS WILL TAKE MOST OF THE
PRECIP SOUTHEAST OF THE AREA THIS EVNG...BUT NORTHWEST WINDS WILL
INCREASE ACROSS MOST OF NWRN INTO SCNTRL SD. THE PREVIOUS WIND ADVY
LOOKS GOOD AND WILL NOT CHANGE. BLSN IS EXPECTED TO BE MINIMAL GIVEN
THE WARM TEMPS AND LIMITED SNOWFALL. A LOW-LEVEL BAROCLINIC ZONE
WILL SETUP OVER THE WRN CWA SO WILL KEEP A CHANCE OF SNOW GOING
THERE. COLDER AIR ALSO WILL FLOW INTO THE CWA TNGT GIVEN STRONG COLD
ADVECTION.
ON WED THE BAROCLINIC ZONE INTENSIFIES ACROSS THE WRN CWA...WITH
WARM ADVECTION AND FRONTOGENESIS AIDING IN MESOSCALE LIFT ON THE
ANTICYCLONIC SIDE OF THE UPPER JET. DESPITE WEAK UPPER FORCING...THE
LOW-LEVEL FORCING AND NEARLY SATURATED PROFILES SHOULD LEAD TO SNOW
OVER NERN WY INTO WRN SD. THIS WILL SPREAD NEWD WED NGT AS UPPER
HEIGHTS CONTINUE TO BUILD AND LOW-LEVEL WARM ADVECTION INTENSIFIES.
SREF PTYPE PROBABILITIES AND NAM VERTICAL PROFILES SUPPORT A CHANCE
OF FZRA OVER PARTS OF NWRN SD LATE WED NGT INTO THU MRNG...SO HAVE
ADDED THAT TO THE FCST.
&&
.LONG TERM...THURSDAY THROUGH TUESDAY
ISSUED AT 205 PM MST TUE NOV 25 2014
SNOW/FREEZING RAIN WILL GRADUALLY EXIT THE AREA ON THANKSGIVING...
LINGERING THE LONGEST OVER NW SD.
THE TRICKIEST PART OF THE LONG TERM FORECAST WILL BE TEMPS...
PARTICULARLY THURSDAY AND SATURDAY. LOW AMPLITUDE RIDGING WILL
DEVELOP THANKSGIVING DAY ACROSS THE ROCKIES INTO THE NORTHERN
PLAINS. STRONG WARM AIR ADVECTION WILL DEVELOP WEDNESDAY NIGHT
INTO THURSDAY PUSHING THE WARM FRONT NE INTO THE CENTRAL DAKOTAS.
THE RESULT WILL BE DRY AND MUCH WARMER WEATHER FOR THANKSGIVING
AND FRIDAY. JUST HOW WARM THE SD PLAINS WILL GET ON THURSDAY
DEPENDS ON THE MOVEMENT OF THE WARM FRONT...AS MODELS HAVE A 10-15
DEGREE SPREAD ACROSS THAT AREA. CURRENTLY HAVE HIGHS RANGING FROM
THE 30S ACROSS NW SD TO THE MID 50S IN PORTIONS OF NE WY AND SW
SD. ON FRIDAY...HIGHS WILL REACH THE UPPER 40S TO MID 50S.
THE NEXT COLD FRONT WILL PASS THROUGH THE AREA SATURDAY AS A SHALLOW
TROUGH CROSSES SRN CANADA INTO MT/ND. AGAIN HIGHS WILL DEPEND ON THE
POSITIONING OF THE FRONT...BUT WILL MOST LIKELY BE REACHED IN THE
MORNING...AS TEMPS WILL BE DROPPING THROUGH THE DAY INTO THE TEENS
AND 20S...AND THEN SINGLE DIGITS OVERNIGHT. GFS AND ECMWF ENSEMBLES
HAVE A 45-50 DEGREE SPREAD FOR THE HIGHS ON SATURDAY...AND ABOUT A
30 DEGREE SPREAD FOR LOWS...SO THERE IS MUCH UNCERTAINTY WITH THE
TEMPERATURE FORECAST. SOME LIGHT SNOW CAN BE EXPECTED TO MOVE
SOUTHWARD BEHIND THE COLD FRONT SATURDAY INTO SATURDAY NIGHT.
WELL BELOW AVERAGE TEMPS ARE EXPECTED SUNDAY...WITH SOME LINGERING
LIGHT SNOW POSSIBLE. THEN MODELS SHOW WARMER AIR ADVECTING BACK IN
EARLY NEXT WEEK POTENTIALLY RESULTING IN NEAR AVERAGE TEMPS.
&&
.AVIATION...FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY
ISSUED AT 205 PM MST TUE NOV 25 2014
SNOW AND A RAIN/SNOW MIX WILL CONTINUE ACROSS MUCH OF THE
REGION...BRINGING WIDESPREAD MVFR/IFR CONDITIONS INTO TONIGHT.
SOME LIFR CONDITIONS EXPECTED AROUND THE NRN BLKHLS. LOW CLOUDS
WILL HANG AROUND THROUGH WEDNESDAY MORNING. NORTHWEST WINDS WILL
BE GUSTY THIS AFTERNOON AND INTO TONIGHT...GRADUALLY DIMINISHING
AFTER MIDNIGHT.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY FROM 7 PM THIS EVENING TO 5 AM MST WEDNESDAY FOR
SDZ014-025-026-031-032-043-072-073.
WIND ADVISORY UNTIL 1 AM MST WEDNESDAY FOR SDZ001-002-012-013.
WY...NONE.
&&
$$
SHORT TERM...BUNKERS
LONG TERM...POJORLIE
AVIATION...POJORLIE
YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
604 PM CST WED NOV 26 2014
.UPDATE...
ISSUED AT 604 PM CST WED NOV 26 2014
STILL HAVE SOME LIGHT SNOW AND FLURRIES FALLING ACROSS THE AREA
EARLY THIS EVENING...BUT MOST OF THE ACCUMULATING SNOW HAS ALREADY
MOVED OUT OF THE ADVISORY AREA. HAVE THUS ALLOWED THE ADVISORY TO
EXPIRE AS SCHEDULED. FOR THE REST OF THE AREA...SOME SPOTS ACROSS
WESTERN AND CENTRAL WISCONSIN INTO NORTHEAST IOWA COULD STILL
RECEIVE ANOTHER HALF INCH OR SO OF ACCUMULATIONS THIS EVENING
UNTIL THE SNOW BAND MOVES OUT OF THE AREA. THIS LOOKS TO BE DRIVEN
BY SOME WEAK FORCING AHEAD OF A SHORT WAVE TROUGH MOVING ACROSS
MINNESOTA ALONG WITH SOME WEAK FRONTOGENESIS IN THE 1000-500 MB
LAYER. BOTH OF THESE FORCING SIGNALS MOVE PAST THE AREA AS THE
WAVE MOVES EAST THIS EVENING WITH THE 26.18Z NAM SUGGESTING THE
FRONTOGENESIS WEAKENS IN ADDITION TO MOVING OUT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 351 PM CST WED NOV 26 2014
AT 3 PM...A SURFACE LOW WAS LOCATED OVER NORTHEAST MISSOURI.
AN INVERTED TROUGH EXTENDS NORTH NORTHWEST OF THIS LOW THROUGH
CENTRAL IOWA INTO SOUTH CENTRAL MINNESOTA. FURTHER NORTHWEST AN
ARCTIC COLD FRONT EXTENDED FROM THE WESTERN TIP OF LAKE SUPERIOR
SOUTHEAST TO SIOUX FALLS SOUTH DAKOTA. TEMPERATURES AHEAD OF THIS
COLD FRONT WERE IN THE MID AND UPPER 20S. MEANWHILE IN THE WAKE OF
THIS FRONT...TEMPERATURES RANGED FROM 0 TO THE LOWER 20S. THE
COMBINATION OF LIFT ASSOCIATED WITH THE TROUGH AND THE COLD FRONT
PRODUCED SNOW ACROSS MUCH OF SOUTH CENTRAL AND SOUTHEAST MINNESOTA
AND EASTERN IOWA. THE HIGHEST SNOW TOTAL /MAINLY DUE TO THE AXIS
PIVOTING ACROSS THIS AREA FOR A LONG DURATION/ WAS 11 INCHES
8 MILES WEST OF FARIBAULT. OUR HIGHEST TOTAL IS 3.8 INCHES IN
MANTORVILLE MINNESOTA /DODGE COUNTY/.
FOR TONIGHT...THE 26.12Z MODELS ARE IN GOOD AGREEMENT THAT THE
TROUGH WILL CONTINUE TO PULL SOUTH AWAY FROM THE AREA AND TAKE
WITH IT THE INVERTED TROUGH WITH IT. THEY ALSO SHOW THAT THE
ARCTIC COLD FRONT WILL MOVE SOUTHEAST THROUGH THE AREA. THIS FRONT
WILL LIKELY EXTEND FROM WISCONSIN RAPIDS TO OELWEIN IOWA AROUND
MIDNIGHT AND WILL BE SOUTH OF THE FORECAST AREA BY 3 AM. THE
MODELS SHOW THAT THAT THE 900 TO 700 FRONTOGENESIS WILL QUICKLY
WEAKEN ACROSS THE AREA THIS EVENING. AS A RESULT...WENT WITH A
RAPIDLY DIMINISHING TREND IN THE SNOW. ADDITIONAL TOTALS WILL BE
UP TO AN INCH IN NORTHEAST IOWA AND SOUTHEAST MINNESOTA...AND FROM
A TRACE TO A HALF INCH IN WESTERN WISCONSIN. WITH IT STILL
SNOWING...WILL JUST LET THE WINTER WEATHER ADVISORY CONTINUE
THROUGH 6 PM.
WITH STRONG COLD AIR ADVECTION IN THE WAKE OF THIS FRONT...EXPECT
HIGH TEMPERATURES FOR THANKSGIVING TO OCCUR BETWEEN MIDNIGHT AND
3 AM TONIGHT. NAEFS STANDARD 850 MB TEMPERATURE ANOMALIES ARE
RUNNING AROUND 2 STANDARD DEVIATIONS BELOW NORMAL. AS A
RESULT...EXPECT HIGH TEMPERATURES TO RANGE FROM NEAR 10 TO 25.
THIS WILL BE THE COLDEST THANKSGIVING IN SOUTHEAST MINNESOTA AND
NORTHEAST IOWA SINCE 1985...AND THE COLDEST IN WESTERN WISCONSIN
SINCE 1958. MORE ON THIS CAN BE FOUND IN THE CLIMATE SECTION OF
THIS PRODUCT.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 351 PM CST WED NOV 26 2014
ON THURSDAY NIGHT AND FRIDAY...MODERATE TO STRONG 925 TO 700 MB
WARM AIR ADVECTION WILL DEVELOP ACROSS THE AREA AS A SHORT WAVE
TROUGH MOVES EAST ACROSS NORTHERN MINNESOTA. IT CONTINUES TO LOOK
LIKE THIS SYSTEM WILL PRODUCE BETWEEN 1.5 AND 3 INCHES ALONG AND
NORTH OF INTERSTATE 94...AND FROM A TRACE TO 1.5 INCHES SOUTH OF
THIS INTERSTATE. SOUNDINGS CONTINUE TO SHOW THAT DRY AIR ABOVE
850 MB WILL MOVE NORTHEAST INTO THE AREA FROM THE CENTRAL PLAINS
ON FRIDAY. THIS DRY AIR WILL SHUTOFF ICE CRYSTAL SEEDING FROM
ALOFT. HOWEVER THERE APPEARS TO BE A DEEP ENOUGH COLD LAYER NEAR
THE SURFACE THAT SOME SNOW COULD STILL DEVELOP INITIALLY...AND
THEN AS THIS LAYER WARMS UP THIS PRECIPITATION COULD POTENTIALLY
SHIFT OVER TO SOME LIGHT FREEZING DRIZZLE...BUT A BIT CONCERNED
THAT BY THIS TIME THERE MAY BE ENOUGH DRY IN THE LOW LEVELS TO
PRECLUDE THIS FROM HAPPENING.
ON FRIDAY NIGHT...THE NAM DEVELOPS FREEZING RAIN NEAR THE
INTERSTATE 90 CORRIDOR. MEANWHILE THE OTHER DETERMINISTIC MODELS
HAVE THE AREA DRY...SO TRENDED THE FORECAST TOWARD THEM. ANOTHER
ISSUE ON FRIDAY NIGHT IS THAT THE LOW TEMPERATURES LOOK TOO COLD
CONSIDERING SOUTHWEST WIND OF 10 TO 15 MPH AND THE MODELS LOOKING
LIKE THEY HAVE TOO MUCH SNOW INITIALIZED IN THEM. THE NAM IN
PARTICULAR IS ABOUT 2 TO 3 INCHES TOO HIGH WITH ITS SNOW DEPTH
ALREADY. DUE TO THIS...RAISED THEM A FEW DEGREES AND ALSO RAISED
SATURDAY MAXIMUM TEMPERATURES TOO.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 522 PM CST WED NOV 26 2014
THE LAST REMAINING BAND OF LIGHT SNOW ASSOCIATED WITH THE
SECONDARY SHORT WAVE TROUGH AND WEAK FRONTOGENESIS BAND IN THE
1000-500 MB LAYER WILL CONTINUE TO MOVE EAST AND WEAKEN THIS
EVENING. UNTIL IT IS PAST THE AREA THOUGH...EXPECT THE IFR
CONDITIONS TO CONTINUE AT KLSE UNTIL ABOUT 01Z OR SO AND THEN A
COUPLE HOUR PERIOD OF MVFR CONDITIONS UNTIL THE SNOW ENDS
COMPLETELY BY THE MIDDLE OF THE EVENING. SHOULD STILL BE AN HOUR
OR SO OF MVFR VISIBILITIES AT KRST AS WELL. NOT EXPECTING MUCH
CHANGE IN THE CEILINGS TO OCCUR THROUGH THE OVERNIGHT HOURS WITH
MVFR PREDOMINATING. SATELLITE DOES SHOW A CLEARING TREND MOVING
INTO NORTHWEST MINNESOTA AS AN AREA OF HIGH PRESSURE DROPS SOUTH
OUT OF CANADA. THE 26.21Z RAP INDICATES THIS CLEARING MOVES INTO
BOTH TAF SITES BY 12Z WHILE THE 26.18Z NAM HOLDS ONTO THE MOISTURE
UNDERNEATH THE INVERSION AND KEEPS THE CLOUDS IN PLACE INTO THE
MORNING AT KRST AND AFTERNOON AT KLSE. FOR NOW...HAVE STAYED WITH
THE TIMING OF THE PREVIOUS FORECAST WHICH ESSENTIALLY SPLIT THE
DIFFERENCE BETWEEN THESE TWO MODELS.
&&
.CLIMATE...THANKSGIVING
ISSUED AT 351 PM CST WED NOV 26 2014
WITH A HIGH TEMPERATURE NEAR 10 DEGREES...ROCHESTER MINNESOTA WILL
BE WITHIN THE TOP 5 FOR THEIR COLDEST THANKSGIVING HIGH
TEMPERATURE. THEY ARE...
1/ 7F 1930
2/ 12F 1985
3/ 14F 1952
4/ 14F 1886
5/ 17F 1956
17F 1919
IT WILL BE ONLY THE 10TH TIME THAT ROCHESTER HAS BEEN 19 DEGREES
OR COLDER ON THANKSGIVING. THE LAST TIME IT OCCURRED WAS 1985.
IN LA CROSSE WISCONSIN...THERE IS STILL SOME QUESTION ON WHETHER
THE HIGH FOR THE DAY WILL BE IN THE TEENS OR NOT. AT MIDNIGHT...THE
HRRR...NAM...SREF...AND RAP HAVE THE HIGH TEMPERATURE BETWEEN 20
AND 22F. MEANWHILE BOTH THE GFS AND ECMWF...HAS A MIDNIGHT HIGH
OF 18F. THIS WOULD PLACE THIS THANKSGIVING IN THE 9 TO 15 RANK.
THEY ARE...
7/ 17F 1919
17F 1952
9/ 19F 1958
19F 1956
19F 1952
12/ 20F 1938
20F 1905
20F 1881
15/ 21F 1903
16/ 23F 1877
THE COLDEST IS 4 DEGREES IN 1872. OUR TEMPERATURE RECORDS FOR
LA CROSSE STARTED JUST OVER A MONTH BEFORE THIS RECORD WAS SET ON
OCTOBER 15 1872. IF WE ARE IN THE TEENS FOR A HIGH TEMPERATURE IT
WILL ONLY BE THE 11TH TIME THAT THIS HAS OCCURRED. IT WILL
DEFINITELY BE THE COLDEST THANKSGIVING AS FAR AS HIGH TEMPERATURE
SINCE 1958 /19F/.
ALSO THIS COULD POTENTIALLY BE THE 21ST CONSECUTIVE THANKSGIVING
WITHOUT MEASURABLE PRECIPITATION IN LA CROSSE. THIS STRETCH IS THE
LONGEST. PRIOR TO THIS STRETCH...THE RECORD WAS 6 YEARS /1900-1905
1909-14 AND 1986-91/.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...04
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
CLIMATE...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
522 PM CST WED NOV 26 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 351 PM CST WED NOV 26 2014
AT 3 PM...A SURFACE LOW WAS LOCATED OVER NORTHEAST MISSOURI.
AN INVERTED TROUGH EXTENDS NORTH NORTHWEST OF THIS LOW THROUGH
CENTRAL IOWA INTO SOUTH CENTRAL MINNESOTA. FURTHER NORTHWEST AN
ARCTIC COLD FRONT EXTENDED FROM THE WESTERN TIP OF LAKE SUPERIOR
SOUTHEAST TO SIOUX FALLS SOUTH DAKOTA. TEMPERATURES AHEAD OF THIS
COLD FRONT WERE IN THE MID AND UPPER 20S. MEANWHILE IN THE WAKE OF
THIS FRONT...TEMPERATURES RANGED FROM 0 TO THE LOWER 20S. THE
COMBINATION OF LIFT ASSOCIATED WITH THE TROUGH AND THE COLD FRONT
PRODUCED SNOW ACROSS MUCH OF SOUTH CENTRAL AND SOUTHEAST MINNESOTA
AND EASTERN IOWA. THE HIGHEST SNOW TOTAL /MAINLY DUE TO THE AXIS
PIVOTING ACROSS THIS AREA FOR A LONG DURATION/ WAS 11 INCHES
8 MILES WEST OF FARIBAULT. OUR HIGHEST TOTAL IS 3.8 INCHES IN
MANTORVILLE MINNESOTA /DODGE COUNTY/.
FOR TONIGHT...THE 26.12Z MODELS ARE IN GOOD AGREEMENT THAT THE
TROUGH WILL CONTINUE TO PULL SOUTH AWAY FROM THE AREA AND TAKE
WITH IT THE INVERTED TROUGH WITH IT. THEY ALSO SHOW THAT THE
ARCTIC COLD FRONT WILL MOVE SOUTHEAST THROUGH THE AREA. THIS FRONT
WILL LIKELY EXTEND FROM WISCONSIN RAPIDS TO OELWEIN IOWA AROUND
MIDNIGHT AND WILL BE SOUTH OF THE FORECAST AREA BY 3 AM. THE
MODELS SHOW THAT THAT THE 900 TO 700 FRONTOGENESIS WILL QUICKLY
WEAKEN ACROSS THE AREA THIS EVENING. AS A RESULT...WENT WITH A
RAPIDLY DIMINISHING TREND IN THE SNOW. ADDITIONAL TOTALS WILL BE
UP TO AN INCH IN NORTHEAST IOWA AND SOUTHEAST MINNESOTA...AND FROM
A TRACE TO A HALF INCH IN WESTERN WISCONSIN. WITH IT STILL
SNOWING...WILL JUST LET THE WINTER WEATHER ADVISORY CONTINUE
THROUGH 6 PM.
WITH STRONG COLD AIR ADVECTION IN THE WAKE OF THIS FRONT...EXPECT
HIGH TEMPERATURES FOR THANKSGIVING TO OCCUR BETWEEN MIDNIGHT AND
3 AM TONIGHT. NAEFS STANDARD 850 MB TEMPERATURE ANOMALIES ARE
RUNNING AROUND 2 STANDARD DEVIATIONS BELOW NORMAL. AS A
RESULT...EXPECT HIGH TEMPERATURES TO RANGE FROM NEAR 10 TO 25.
THIS WILL BE THE COLDEST THANKSGIVING IN SOUTHEAST MINNESOTA AND
NORTHEAST IOWA SINCE 1985...AND THE COLDEST IN WESTERN WISCONSIN
SINCE 1958. MORE ON THIS CAN BE FOUND IN THE CLIMATE SECTION OF
THIS PRODUCT.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 351 PM CST WED NOV 26 2014
ON THURSDAY NIGHT AND FRIDAY...MODERATE TO STRONG 925 TO 700 MB
WARM AIR ADVECTION WILL DEVELOP ACROSS THE AREA AS A SHORT WAVE
TROUGH MOVES EAST ACROSS NORTHERN MINNESOTA. IT CONTINUES TO LOOK
LIKE THIS SYSTEM WILL PRODUCE BETWEEN 1.5 AND 3 INCHES ALONG AND
NORTH OF INTERSTATE 94...AND FROM A TRACE TO 1.5 INCHES SOUTH OF
THIS INTERSTATE. SOUNDINGS CONTINUE TO SHOW THAT DRY AIR ABOVE
850 MB WILL MOVE NORTHEAST INTO THE AREA FROM THE CENTRAL PLAINS
ON FRIDAY. THIS DRY AIR WILL SHUTOFF ICE CRYSTAL SEEDING FROM
ALOFT. HOWEVER THERE APPEARS TO BE A DEEP ENOUGH COLD LAYER NEAR
THE SURFACE THAT SOME SNOW COULD STILL DEVELOP INITIALLY...AND
THEN AS THIS LAYER WARMS UP THIS PRECIPITATION COULD POTENTIALLY
SHIFT OVER TO SOME LIGHT FREEZING DRIZZLE...BUT A BIT CONCERNED
THAT BY THIS TIME THERE MAY BE ENOUGH DRY IN THE LOW LEVELS TO
PRECLUDE THIS FROM HAPPENING.
ON FRIDAY NIGHT...THE NAM DEVELOPS FREEZING RAIN NEAR THE
INTERSTATE 90 CORRIDOR. MEANWHILE THE OTHER DETERMINISTIC MODELS
HAVE THE AREA DRY...SO TRENDED THE FORECAST TOWARD THEM. ANOTHER
ISSUE ON FRIDAY NIGHT IS THAT THE LOW TEMPERATURES LOOK TOO COLD
CONSIDERING SOUTHWEST WIND OF 10 TO 15 MPH AND THE MODELS LOOKING
LIKE THEY HAVE TOO MUCH SNOW INITIALIZED IN THEM. THE NAM IN
PARTICULAR IS ABOUT 2 TO 3 INCHES TOO HIGH WITH ITS SNOW DEPTH
ALREADY. DUE TO THIS...RAISED THEM A FEW DEGREES AND ALSO RAISED
SATURDAY MAXIMUM TEMPERATURES TOO.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 522 PM CST WED NOV 26 2014
THE LAST REMAINING BAND OF LIGHT SNOW ASSOCIATED WITH THE
SECONDARY SHORT WAVE TROUGH AND WEAK FRONTOGENESIS BAND IN THE
1000-500 MB LAYER WILL CONTINUE TO MOVE EAST AND WEAKEN THIS
EVENING. UNTIL IT IS PAST THE AREA THOUGH...EXPECT THE IFR
CONDITIONS TO CONTINUE AT KLSE UNTIL ABOUT 01Z OR SO AND THEN A
COUPLE HOUR PERIOD OF MVFR CONDITIONS UNTIL THE SNOW ENDS
COMPLETELY BY THE MIDDLE OF THE EVENING. SHOULD STILL BE AN HOUR
OR SO OF MVFR VISIBILITIES AT KRST AS WELL. NOT EXPECTING MUCH
CHANGE IN THE CEILINGS TO OCCUR THROUGH THE OVERNIGHT HOURS WITH
MVFR PREDOMINATING. SATELLITE DOES SHOW A CLEARING TREND MOVING
INTO NORTHWEST MINNESOTA AS AN AREA OF HIGH PRESSURE DROPS SOUTH
OUT OF CANADA. THE 26.21Z RAP INDICATES THIS CLEARING MOVES INTO
BOTH TAF SITES BY 12Z WHILE THE 26.18Z NAM HOLDS ONTO THE MOISTURE
UNDERNEATH THE INVERSION AND KEEPS THE CLOUDS IN PLACE INTO THE
MORNING AT KRST AND AFTERNOON AT KLSE. FOR NOW...HAVE STAYED WITH
THE TIMING OF THE PREVIOUS FORECAST WHICH ESSENTIALLY SPLIT THE
DIFFERENCE BETWEEN THESE TWO MODELS.
&&
.CLIMATE...THANKSGIVING
ISSUED AT 351 PM CST WED NOV 26 2014
WITH A HIGH TEMPERATURE NEAR 10 DEGREES...ROCHESTER MINNESOTA WILL
BE WITHIN THE TOP 5 FOR THEIR COLDEST THANKSGIVING HIGH
TEMPERATURE. THEY ARE...
1/ 7F 1930
2/ 12F 1985
3/ 14F 1952
4/ 14F 1886
5/ 17F 1956
17F 1919
IT WILL BE ONLY THE 10TH TIME THAT ROCHESTER HAS BEEN 19 DEGREES
OR COLDER ON THANKSGIVING. THE LAST TIME IT OCCURRED WAS 1985.
IN LA CROSSE WISCONSIN...THERE IS STILL SOME QUESTION ON WHETHER
THE HIGH FOR THE DAY WILL BE IN THE TEENS OR NOT. AT MIDNIGHT...THE
HRRR...NAM...SREF...AND RAP HAVE THE HIGH TEMPERATURE BETWEEN 20
AND 22F. MEANWHILE BOTH THE GFS AND ECMWF...HAS A MIDNIGHT HIGH
OF 18F. THIS WOULD PLACE THIS THANKSGIVING IN THE 9 TO 15 RANK.
THEY ARE...
7/ 17F 1919
17F 1952
9/ 19F 1958
19F 1956
19F 1952
12/ 20F 1938
20F 1905
20F 1881
15/ 21F 1903
16/ 23F 1877
THE COLDEST IS 4 DEGREES IN 1872. OUR TEMPERATURE RECORDS FOR
LA CROSSE STARTED JUST OVER A MONTH BEFORE THIS RECORD WAS SET ON
OCTOBER 15 1872. IF WE ARE IN THE TEENS FOR A HIGH TEMPERATURE IT
WILL ONLY BE THE 11TH TIME THAT THIS HAS OCCURRED. IT WILL
DEFINITELY BE THE COLDEST THANKSGIVING AS FAR AS HIGH TEMPERATURE
SINCE 1958 /19F/.
ALSO THIS COULD POTENTIALLY BE THE 21ST CONSECUTIVE THANKSGIVING
WITHOUT MEASURABLE PRECIPITATION IN LA CROSSE. THIS STRETCH IS THE
LONGEST. PRIOR TO THIS STRETCH...THE RECORD WAS 6 YEARS /1900-1905
1909-14 AND 1986-91/.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ086-
094.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ008-
018-019.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
CLIMATE...BOYNE
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1005 AM CST TUE NOV 25 2014
.UPDATE...
THERE ARE STILL A FEW POCKETS OF SUNSHINE OUT THERE...BUT CLOUDS
CONTINUE TO FILL IN THIS MORNING. LATEST RAP SOUNDINGS INDICATE
MOSTLY CLOUDY SKIES INTO THIS EVENING...SO WILL LIKELY HAVE TO
BUMP UP CLOUD COVER. TEMPERATURES ARE ALREADY WITHIN A FEW DEGREES
OF FORECAST HIGHS...SO NO MAJOR CHANGES EXPECTED WITH TEMPS FOR
THE REMAINDER OF THE DAY.
&&
.AVIATION/18Z TAFS/...
LATEST SOUNDINGS INDICATE LOWER CLOUDS MAY STICK AROUND INTO THE
EVENING...OR POSSIBLY LATER. WILL CONTINUE TO EVALUATE NEW MODEL
DATA AS IT COMES IN AND ADJUST TAFS AS NEED BE. OTHERWISE...IT
LOOKS FAIRLY QUIET THROUGH WEDNESDAY...WITH A LITTLE LIGHT SNOW
APPROACHING BY WEDNESDAY EVENING. COULD THEN SEE A DUSTING OR
COUPLE TENTHS OF AN INCH OF SNOW WEDNESDAY NIGHT AS A WEAK WAVE
PUSHES THROUGH.
&&
.PREV DISCUSSION... /ISSUED 340 AM CST TUE NOV 25 2014/
SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
ANY LINGERING LIGHT SNOW/FLURRIES WILL END BY MID MORNING AS THE
REMNANTS OF THE SURFACE TROUGH PULLS OFF TO THE NORTHEAST AND WE
FINALLY GET INTO SOME RIDGING. THAT RIDGE WILL PROTECT US THROUGH
TONIGHT AS ANOTHER LOW PRESSURE SYSTEM IS ALREADY APPROACHING FROM
THE WEST. THE CLOUDS SHOULD DIMINISH SLOWLY FROM WEST TO EAST
TODAY. A CHILLY DAY IS ON TAP WITH HIGHS IN THE MID TO UPPER 20S AND
LOW DROPPING DOWN IN THE TEENS TONIGHT. TEMPS TONIGHT ARE A BIT
TRICKY. WE SHOULD SEE SOME HIGH CLOUDS SPREAD IN...BUT IF WE STAY
MOSTLY CLEAR TOO LONG TEMPS COULD DROP A BIT MORE DUE TO THE LIGHT
WINDS UNDER THE RIDGE.
WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDENCE HIGH.
ONE MORE SHORTWAVE TROUGH WILL TRACK ACROSS THE MIDWEST WEDNESDAY
INTO THURSDAY. THE STRONGER PORTION OF IT ROUNDING THE BASE OF THE
UPPER TROUGH WILL MISS US TO THE SOUTH WED AFTERNOON/EVENING. A
WEAKER SHORTWAVE WILL CROSS WI WED NIGHT... AND THIS IS THE ONE THAT
WILL BRING SOUTHERN WI THE NEXT CHANCE FOR SNOW. IT WILL BE A LIGHT
EVENT... WITH UP TO AN INCH OF DRY SNOW THROUGH THURSDAY MORNING.
FLURRIES COULD LINGER THROUGH MUCH OF THANKSGIVING DAY DUE TO LOW
LEVEL MOISTURE AND CYCLONIC FLOW ALOFT. EXPECT CLOUDY SKIES AND
STEADY TEMPERATURES IN THE LOWER 20S WITH A NORTHWEST BREEZE.
THURSDAY NIGHT...FORECAST CONFIDENCE HIGH.
TEMPERATURES WILL DROP QUICKLY IN THE EVENING AS SKIES CLEAR AND
HIGH PRESSURE SPREADS IN. LOWS WILL BE AROUND 10 INLAND WITH LIGHT
WINDS. TEMPERATURES WILL BEGIN TO WARM LATE THURSDAY NIGHT WITH
INCREASING CLOUDS.
LONG TERM...
FRIDAY... FORECAST CONFIDENCE HIGH.
THE UPPER LEVEL FLOW WILL BECOME MORE ZONALLY ORIENTED FOR THE
LATTER HALF OF THE WEEK. A PAIR OF WEAK SHORTWAVES DUE TO A
STRENGTHENING UPPER JET OVER THE NORTHERN PLAINS WILL MAKE THEIR WAY
INTO THE UPPER MIDWEST LATE THURSDAY NIGHT THROUGH FRIDAY. THE BEST
CHANCE FOR SNOW IN SOUTHERN WI WILL BE FRIDAY MORNING WITH ANOTHER
INCH POSSIBLE... LOWEST AMOUNTS NEAR THE ILLINOIS BORDER.
WARMER AIR ALOFT WILL LIFT INTO SOUTHERN WI FRIDAY AFTERNOON. AT
THIS TIME... IT LOOKS LIKE JUST SOUTHWEST AND PORTIONS OF SOUTH
CENTRAL WI WILL GET INTO AN AREA WHERE TEMPERATURES ALOFT WILL BE
WARMER THAN THE SURFACE TEMPS SUGGESTING FREEZING RAIN. MODEL
SOUNDINGS SHOW THE MAJORITY OF THE MOISTURE MOVING OUT OF SOUTHERN
WI BY THE TIME THE TEMPS ALOFT WARM ABOVE FREEZING. THE GFS PROFILE
ACTUALLY SUGGESTS FREEZING DRIZZLE SINCE THE UPPER LEVELS DRY OUT
EARLIER THAN THE LOWER LEVELS.
FRIDAY NIGHT THROUGH SATURDAY... FORECAST CONFIDENCE MEDIUM.
WE WILL FINALLY GET INTO A PERIOD OF QUIET WEATHER WITH MILD
TEMPERATURES. THE GFS HAS A MORE SHEARED VORT MAX OVER SOUTHERN
CANADA THAN THE SLIGHTLY MORE-AMPLIFIED ECMWF. THUS... THERE ARE
TIMING DIFFERENCES BETWEEN THE MODELS ABOUT WHEN THE WARMEST TEMPS
WILL BE OVER SOUTHERN WI. THE ECMWF IS WARMEST DURING THE DAY
SATURDAY WHILE THE GFS GIVES US A SHORTER WARM PERIOD FRIDAY NIGHT
AND SHOWS SOME LIGHT QPF FOR SATURDAY AFTERNOON. I KEPT THE FORECAST
DRY FOR NOW AND USED A MODEL CONSENSUS FOR HIGHS IN THE UPPER
30S/LOWER 40S ON SATURDAY. THIS IS A CONSERVATIVE FORECAST AS WE
COULD SEE EVEN WARMER TEMPS IF THE ECMWF VERIFIES.
SUNDAY AND BEYOND... FORECAST CONFIDENCE MEDIUM.
A COLD FRONT WILL DROP DOWN THROUGH WI SUNDAY MORNING AND BRING US A
QUICK-HITTING COLD SNAP. EXPECT TEMPERATURES TO WARM ONCE AGAIN
TUESDAY AND WEDNESDAY NEXT WEEK THOUGH.
AVIATION/12Z TAFS/...LOOK FOR MVFR CONDITIONS DUE TO CIGS THIS
MORNING...IMPROVING TO VFR AS HIGH PRESSURE GRADUALLY BUILDS BACK
INTO THE REGION. ANY LINGERING LIGHT SNOW OR FLURRIES ACROSS THE
SOUTHEAST WILL END BY MID MORNING AS A TROF OF LOW PRESSURE FINALLY
EXITS TO THE NORTHEAST. ONCE CIGS LIFT TO VFR LEVELS...LOOK FOR THIS
TO CONTINUE THROUGH THE REMAINDER OF THE TAF PERIOD.
MARINE...THE SMALL CRAFT ADVISORY WILL BE CANCELED EARLY DUE TO
WESTERLY WINDS DIMINISHING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
342 AM CST TUE NOV 25 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 342 AM CST TUE NOV 25 2014
RADAR EARLY THIS MORNING SHOWING FINAL SNOW BAND ON THE BACK SIDE OF
DEPARTING LOW PRESSURE SYSTEM MAKING ITS WAY ACROSS CENTRAL
WISCONSIN. THIS SHOULD CLEAR THE AREA BY 6 AM WITH LITTLE IN THE WAY
OF ADDITIONAL ACCUMULATION EXPECTED. THEN FOR TODAY...A RIDGE OF
HIGH PRESSURE BUILDS OVER THE AREA FOR SOME CLEARING. MODEL
SOUNDINGS SHOWING STRATUS MAY BE A BIT MORE PESKY EAST OF THE
MISSISSIPPI RIVER UNDER THE SUBSIDENCE INVERSION. THINKING THIS
STRATUS WILL CONTINUE TO THIN THROUGH THE DAY...BUT MAY BE A BIT
SLOWER THAN ANTICIPATED. WILL HAVE TO KEEP AN EYE ON THIS.
OTHERWISE...LOOK FOR HIGHS TODAY IN THE 20S WITH NORTHWEST WINDS
THIS MORNING BECOMING SOUTHWEST BY AFTERNOON WITH THE PASSAGE OF THE
HIGH PRESSURE RIDGE AXIS.
FOR TONIGHT THROUGH WEDNESDAY...WILL BE WATCHING A FAIRLY VIGOROUS
MID-LEVEL SHORTWAVE TROUGH AND SURFACE LOW DROP SOUTHEAST ACROSS THE
DAKOTAS...THROUGH IOWA...AND THEN TOWARD THE MID-MISSISSIPPI VALLEY.
MODELS ARE IN VERY GOOD AGREEMENT IN KEEPING BULK OF SNOWFALL
ASSOCIATED WITH THIS FEATURE WEST OF THE AREA...BUT LOOKS LIKE
PORTIONS OF NORTHEAST IA/SOUTHEAST MN WILL LIKELY GET CLIPPED WITH
SOME LIGHT SNOW DURING THE DAY WEDNESDAY. RIGHT NOW IT APPEARS
SNOWFALL OF 1 TO PERHAPS 3 INCHES ON THE HIGHEST END IS LIKELY
MAINLY ALONG AND WEST OF A ROCHESTER MN TO OELWEIN IA LINE.
MEANWHILE ON WEDNESDAY...WILL BE WATCHING AN ARCTIC FRONT DROPPING
THROUGH MN INTO WESTERN WI BY LATE IN THE AFTERNOON. NAM SHOWING
PRETTY DECENT AMOUNT OF 1000-700MB FRONTOGENESIS AND SHOULD PROVIDE
ENOUGH FORCING FOR THE LIKELIHOOD OF SOME SNOW SHOWER ACTIVITY.
LOOK FOR THIS FRONT AND BAND OF SNOW SHOWERS TO SWING THROUGH THE
AREA WEDNESDAY NIGHT...WITH THE BULK OF IT EXITING BEFORE
THANKSGIVING DAYBREAK. THINKING THAT WE COULD SEE UPWARDS OF AN INCH
OF SNOW WITH THE SNOW SHOWERS WITH BEST CHANCES FOR ACCUMULATION
ALONG AND NORTH OF I-94 WHERE BEST FORCING WILL RESIDE.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 342 AM CST TUE NOV 25 2014
DRY/SUNNY/COLD CONDITIONS WILL BE SEEN FOR THANKSGIVING DAY AS
ARCTIC HIGH/MODIFIED ARCTIC AIRMASS DRIFTS ACROSS THE REGION. PLAN
ON HIGHS ONLY IN THE TEENS.
A WARM FRONT WILL THEN LIFT NORTHWARD THROUGH THE REGION THURSDAY
NIGHT THROUGH FRIDAY NIGHT FOR A CHANCE OF LIGHT SNOW. TEMPERATURES
ARE EXPECTED TO SLOWLY RISE THURSDAY NIGHT....THEN TOP OFF IN THE
20S TO LOWER 30S ON FRIDAY. LOOKS LIKE WE WILL BE IN THE WARM SECTOR
OF APPROACHING LOW PRESSURE ACROSS THE PLAINS ON SATURDAY. HIGHS ON
SATURDAY IN THE LOWER 30S FOR AREAS ALONG AND NORTH OF I-94...TO
PERHAPS A FEW 40 DEGREE READINGS ACROSS NORTHEAST IA INTO SOUTHWEST
WISCONSIN.
LOOK FOR A RETURN TO COLDER CONDITIONS SUNDAY AND MONDAY AS ARCTIC
AIR SPILLS BACK INTO THE REGION. PLAN ON HIGHS BOTH DAYS IN THE 20S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1100 PM CST MON NOV 24 2014
THE SNOW HAS EXITED TO THE EAST LATE THIS EVENING...AS THE
RESPONSIBLE AREA OF LOW PRESSURE CONTINUES TO TREK ACROSS THE
EASTERN GREAT LAKES. THE ASSOCIATED CLOUDS LINGER WELL WEST OF THE
LOW THOUGH...WITH CURRENT SATELLITE TRENDS SUGGESTING CLEARING OF
THE MVFR DECK AT KRST AROUND 11Z AND KLSE BY 14Z. SHOULD SEE SCT/VFR
CONDITIONS FOR THE BULK OF THE DAY TUE.
SEE SOME POTENTIAL FOR A RETURN FOR AN MVFR DECK AFTER 00Z WED /TUE
NIGHT/. RAP AND NAM12 RH FIELDS SUGGEST CURRENT STRATUS DECK OVER ND
WILL SINK SOUTHEAST OVERNIGHT THROUGH TUE...AND COULD HOLD TOGETHER
LONG ENOUGH TO IMPACT KRST...POSSIBLY KLSE. WILL ALLUDE TO IT FOR
NOW...ADDING IN A SCATTERED LOW CLOUD IN ADDITION TO BKN HIGH CIGS.
DO EXPECT SOME LOWER CIGS TO RETURN ON WED AS THE NEXT UPPER LEVEL
SHORTWAVE TRACKS ACROSS PARTS OF THE REGION. LIKELY SEE SOME -SN TOO.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 PM CST MON NOV 24 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 341 PM CST MON NOV 24 2014
A PROGRESSIVE AND ENERGETIC FLOW PERSISTS OVER THE CONUS THROUGH
THIS WEEK WITH AN EVOLUTION TO MORE OF A ZONAL OR BROAD FLAT RIDGE
IN THE LARGE SCALE. PREDICTABILITY OVER THE PAST WEEKEND HAS BEEN
LOW...AS SEEN BY THE SHORT RANGE VARIABILITY IN HOW THIS CURRENT
SNOW EVENT TRANSPIRED. NOT PRETTY. THIS WILL CONTINUE THROUGH THE
WEEK...AND CONFIDENCE IS LOW IN TIMING AND PLACEMENT OF WEATHER
SYSTEMS.
LATEST SNOW AMOUNTS IN CENTRAL WISCONSIN ARE IN THE 3 TO 5 INCH
RANGE WITH WINDS CAUSING SOME MEASUREMENT DIFFICULTY. RADAR
INDICATING THAT MOST OF THE CENTRAL WI AREA SHOULD CONTINUE TO
DIMINISH IN INTENSITY AS SNOW SHIELD MOVES NORTHEAST. THE LATEST
RAP TRENDS INDICATE A STRENGTHENING 600-700MB WEAK-MODERATE
FRONTOGENESIS BAND WILL DEVELOP N-S OVER CENTRAL WI LATER THIS
AFTERNOON WHICH COULD BUMP THE RATES A BIT ON WEST END OF THE
SHIELD. BUT...THAT RAP FRONTOGENESIS GUIDANCE IN THE MID-LEVELS
HAS NOT PROVIDED MUCH FOR SENSIBLE SNOW INCREASE OR BANDING FOR
THIS ENVIRONMENT. OVERALL...FROM TRENDS AND WHAT HAS FALLEN...SNOW
WILL SLOWLY SHIFT EAST THIS EVENING...DIMINISHING. HAVE LOWER
STORM TOTAL AMOUNTS IN CENTRAL WISCONSIN...MORE AROUND 4.5 TO 5
INCHES...AND AFTER COLLABORATION WITH MKX...HAVE DOWNGRADED THE
WARNING TO ADVISORY.
WINDS WILL CONTINUE THROUGH THE EVENING TO CAUSE ROADS TO BE
COVERED AND SNOW PLOW CAMS IN NORTHEAST IA SUGGEST THE ROADS ARENT
TOO CLEAN YET. SO...HAVE DECIDED TO LET THE ENTIRE ADVISORY
CONTINUE THROUGH MIDNIGHT.
WATER VAPOR IMAGERY SHOWING A SHORTWAVE TROUGH DROPPING THROUGH MN
AND RADAR INDICATES SOME SNOW SHOWERS THERE. THIS SHOULD NOT
AMOUNT TO MUCH BUT A BRIEF SNOW SHOWER PERIOD AND MAYBE A BIT OF
VSBY REDUCTION /1-2SM/...BUT NOT A HAZARD GENERALLY. HOWEVER AN
AREA EXISTS AHEAD OF THE SHORTWAVE TROUGH IN MN AND THE HIGHER
LEVEL CLOUD WITH THE SNOW SHIELD THAT IS PROMOTING SOME FZDZ.
THIS IS FROM SERN MN INTO SWRN WI. SHERIFFS HAVE HAD FZDZ IN GRANT
COUNTY...AND EARLIER IN NERN IA. MOST OF THIS FZDZ SHOULD OCCUR
IN THE ADVISORY AREA AND FOR THE NEXT FEW HOURS AS THE DEEP SNOW
SHOWERS MOVING IN WILL SHIFT THE PRECIPITATION TYPE VIA SEEDER-
FEEDER.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 341 PM CST MON NOV 24 2014
A FAIRLY TRANQUIL PERIOD FOR THE WEEK REALLY WITH A COLDER THAN
NORMAL PERIOD UNDER THE DEEP LONG WAVE TROUGH....BUT AS THIS
BECOMES MORE ZONAL...THE AREA WILL SEE CYCLES OF WARM ADVECTION
AND PRECIPITATION CHANCES...CYCLONE PASSAGE...AND COLD AIR PUSHES.
THE FIRST SHORTWAVE TROUGH COMES ON WEDNESDAY...A HEAVIER TRAVEL
DAY. THIS SHORTWAVE IS COMING INTO BRITISH COLUMBIA COAST
CURRENTLY ON THE POLEWARD SIDE OF A 155 KT 250 MB JET PER 12Z
RAOBS. A PRETTY VIGOROUS SYSTEM THAT DIGS SOUTHEAST IN THE
LONGWAVE TROUGH. THIS WILL BE A 1-2 INCH SNOW MAKER BUT THE TRACK
IS THE QUESTION. HAVE GENERALLY KEPT THE SAME FORECAST AS PREVIOUS
WITH MOSTLY A SRN MN AND NERN IA SYSTEM. CONFIDENCE ON THE TRACK
IS NOT HIGH YET WITH COMPLEX SYSTEM OVER GREAT LAKES AND TOTAL
ENERGY OVER THE CONUS RIGHT NOW. NEW GFS PARALLEL RUN INTENSIFIES
THE NWRLY FLOW ENERGY MORE AND BRINGS MORE SNOW TO THE NORTH...BUT
IS AN OUTLIER. BEHIND THIS SYSTEM...COLD AIR COMES IN FOR
THANKSGIVING...BUT A QUITE WEATHER DAY.
ANOTHER SYSTEM MOVES IN FRIDAY AND IF MY CONFIDENCE IS LOW ON THE
TRACK FOR WEDNESDAY...FRIDAYS WARM ADVECTION SWATH OF SNOW OR
WINTER MIX IS LOWER. GOOD MEDIUM RANGE GUIDANCE CONSENSUS ON THE
TRACK RIGHT NOW...BUT THAT DOESNT MEAN IT WILL BE CORRECT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1100 PM CST MON NOV 24 2014
THE SNOW HAS EXITED TO THE EAST LATE THIS EVENING...AS THE
RESPONSIBLE AREA OF LOW PRESSURE CONTINUES TO TREK ACROSS THE
EASTERN GREAT LAKES. THE ASSOCIATED CLOUDS LINGER WELL WEST OF THE
LOW THOUGH...WITH CURRENT SATELLITE TRENDS SUGGESTING CLEARING OF THE
MVFR DECK AT KRST AROUND 11Z AND KLSE BY 14Z. SHOULD SEE SCT/VFR
CONDITIONS FOR THE BULK OF THE DAY TUE.
SEE SOME POTENTIAL FOR A RETURN FOR AN MVFR DECK AFTER 00Z WED /TUE
NIGHT/. RAP AND NAM12 RH FIELDS SUGGEST CURRENT STRATUS DECK OVER ND
WILL SINK SOUTHEAST OVERNIGHT THROUGH TUE...AND COULD HOLD TOGETHER
LONG ENOUGH TO IMPACT KRST...POSSIBLY KLSE. WILL ALLUDE TO IT FOR
NOW...ADDING IN A SCATTERED LOW CLOUD IN ADDITION TO BKN HIGH CIGS.
DO EXPECT SOME LOWER CIGS TO RETURN ON WED AS THE NEXT UPPER LEVEL
SHORTWAVE TRACKS ACROSS PARTS OF THE REGION. LIKELY SEE SOME -SN TOO.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM....BAUMGARDT
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS ALBANY NY
425 AM EST THU NOV 27 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL BRING SOME SCATTERED SNOW SHOWERS
TO REGION TODAY INTO TONIGHT. HIGH PRESSURE WILL RIDGE IN BRIEFLY
FOR FRIDAY WITH BELOW NORMAL TEMPERATURES. MILDER AIR ATTEMPTS TO
BUILD INTO THE REGION THIS WEEKEND...HOWEVER...IT WILL BE
ACCOMPANIED BY CLOUD COVER AND THE CHANCE FOR LIGHT SNOW OR RAIN
SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE NOR`EASTER THAT PRODUCED A SIGNIFICANT SNOWFALL FOR THE REGION
WAS QUICKLY DEPARTING OFF THE COAST OF MAINE THIS MORNING /WAS
993MB AS OF 08Z/. DEFORMATION AXIS THAT MOVED ACROSS THE NORTHERN
2/3RDS OF THE REGION WAS TOO QUICKLY LIFTING NORTHEAST ACROSS NEW
ENGLAND AS SEEN IN THE COLDER IR SATELLITE IMAGERY CLOUD TOPS.
THROUGH THE NEXT FEW HOURS...WE CONTINUE TO WATCH THE POTENTIAL
MESOSCALE MOHAWK-HUDSON VALLEY CONVERGENCE AS METARS AND
STREAMLINE ANALYSIS POINT TOWARD WINDS CONVERGING INTO THE CAPITAL
REGION...HOWEVER...IT WAS ALSO FIGHTING SUBSIDENCE IN THE WAKE OF
THE NOR`EASTER. FOR NOW...WE WILL CONTINUE WITH CHC-SLIGHT CHC POPS
THROUGH THE EARLY MORNING HOURS.
H2O VAPOR LOOP DEPICTS A DEEP TROUGH ACROSS THE EASTERN 2/3RDS OF
NOAM. A COUPLE OF RATHER POTENT SHORT WAVES WERE OBSERVED...ONE
APPROACHING THE OHIO RIVER VALLEY AND THE OTHER TRACKING INTO THE
WESTERN GREAT LAKES. TEMPERATURES ALOFT WITH THESE FEATURES ARE
QUITE COLD WITH SUB -30C AIR AT H500 AND ABOVE. NCEP MODEL SUITE
AND INTERNATIONAL GUIDANCE ARE IN GOOD AGREEMENT WITH TRACKING
THESE WAVES ACROSS THE CWFA TODAY. QG FORCING WAS PRONOUNCED LATE
THIS MORNING INTO THE AFTERNOON HOURS ALONG WITH STEEPENING LAPSE
RATES THAT SHOULD RESULT WITH AN INCREASE IN SNOW SHOWER ACTIVITY
COVERAGE. 4KM SPC AND HRRR REFLECTIVITIES DO INDICATE AN INCREASE
IN COVERAGE OF SNOW SHOWERS AS WE WILL REFLECT THIS IN THE
GRIDS/FORECAST WITH RAISING POPS. MOST OF THE HIGHER POP VALUES
WILL BE INTO THE TERRAIN WITH OROGRAPHIC LIFTING. AS FOR
ADDITIONAL ACCUMULATIONS...WE COULD SEE AN ADDITIONAL INCH OR SO.
GUIDANCE TEMPERATURES ARE VERY CLOSE...HOWEVER...WITH FRESH SNOW
COVER WE WILL LEAN TOWARD A SLIGHTLY COOLER VALUES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
RIDGING WILL BE BUILDING INTO THE REGION...HOWEVER...LAKE EFFECT
SNOW SHOWERS DOWNWIND OF LAKE ONTARIO WILL THE MAIN WEATHER ISSUE
ON FRIDAY. LATEST NAM12 SUGGESTS THE LOW LEVEL BOUNDARY LAYER
WINDS WILL INITIALLY BE NORTHWEST...BUT AS THE RIDGE
BUILDS...THOSE WINDS BE BACKING WITH TIME. THIS WOULD SUGGEST LAKE
EFFECT ACTIVITY THAT WILL BE WEST OF THE REGION INITIALLY TO
MIGRATE INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN
DACKS. DUE TO THE MIGRATORY NATURE...THE INLAND EXTENT IS EXPECTED
TO BE LIMITED AS WE WILL KEEP POPS INTO THE CHC-SCT CATEGORY.
OTHERWISE...THE REMAINDER OF THE REGION WILL BE RATHER TRANQUIL
WITH SOME PEAKS OF SUNSHINE. AS H850 TEMPS WILL RANGE BETWEEN -12C
TO -14C...IT WILL BE UNSEASONABLY COOL FOR LATE NOVEMBER.
FRIDAY NIGHT INTO SATURDAY...HIGH PRESSURE MOVES OFF THE ATLANTIC
SEABOARD AS STORM ATTEMPTS TO ORGANIZE ACROSS THE NORTHERN PLAINS
AND GREAT LAKES REGION. THIS WILL PLACE OUR REGION INTO A WARM
ADVECTION REGIME. ALTHOUGH...LOW LEVEL MOISTURE WILL REMAIN RATHER
HIGH TO KEEP CLOUDS IN THE FORECAST. AS FOR PRECIP
POTENTIAL...BROAD ISENTROPIC LIFT WILL BE UNDERWAY WITH THE BEST
LOWERING OF THE CPD/S TO BE NORTH AND WEST OF THE CWFA.
HOWEVER...SINCE THE LOW LEVELS WILL BECOME RATHER HIGH IN MOISTURE
CONTENT...WE WILL CONTINUE WITH THE CHC POPS OF LIGHT
PRECIPITATION THROUGH THE PERIOD. MOST OF THIS PRECIP SHOULD FALL
AS WINTER TYPE BUT SOME OF THE WARMER VALLEY LOCATIONS MAY
EXPERIENCE A MIX OF RAIN/SNOW SHOWERS.
GUIDANCE TEMPERATURES DIVERGE THROUGH THE SHORT TERM AND PER THE
CURRENT SNOW PACK...WE WILL LEAN TOWARD THE COOLER SIDE OF THE
GUIDANCE ENVELOPE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
LONG TERM PERIOD CHARACTERIZED BY CHANGEABLE WEATHER AND WIDELY
VARYING TEMPERATURES AS A SERIES OF FRONTS CROSS EASTERN NEW YORK
AND WESTERN NEW ENGLAND.
FOR SUNDAY...A WARM FRONT WILL BE CROSSING THE FORECAST AREA. FOR
NOW HAVE SLIGHT CHANCE POPS OVER MOST OF THE AREA WITH CHANCE POPS
OVER SOUTHWESTERN ADIRONDACKS AS BEST FORCING FOR ANY PRECIPITATION
MOVES NORTH OF THE AREA. AFTER A COLD THANKSGIVING WEEKEND...
TEMPERATURES SHOULD MODERATE BY LATE ON SUNDAY WITH HIGHS 40S
VALLEYS AND SOME 30S HIGHEST ELEVATIONS.
ONE OF THE MORE TRICKY PARTS OF THE EXTENDED FORECAST IS THE LOW
TEMPERATURE FORECAST ON MONDAY MORNING. THERE WILL LIKELY STILL BE
SIGNIFICANT SNOW COVER ACROSS THE AREA. IF WE CAN DECOUPLE THE
BOUNDARY LAYER FROM THE GRADIENT WIND FLOW...WITH CLEARING SKIES
TOWARD DAYBREAK...TEMPERATURES MAY FALL A GOOD TEN TO FIFTEEN
DEGREES BELOW FREEZING. FOR NOW WENT WITH LOWS AROUND FREEZING AND
THIS WILL LIKELY BE ADJUSTED AS WE GET LATER IN THE WEEKEND. A COLD
FRONT WILL CROSS THE AREA LATER MONDAY...BUT TEMPERATURES SHOULD
ONCE AGAIN REACH THE 40S IN THE VALLEYS BEFORE THE FRONT MOVES
THROUGH. A LITTLE COOLER IN THE HILLS WITH UPPER 30S FOR HIGHS.
TUESDAY LOOKS GENERALLY FAIR AND COLD BEHIND THE COLD FRONT. LOWS IN
THE TEENS AND TWENTIES AND HIGHS IN THE 20S AND 30S.
BY WEDNESDAY THE NEXT WARM FRONT IS SURGING TOWARDS THE AREA. THERE
MAY BE A BURST OF WARM ADVECTION PRECIPITATION AROUND DAYBREAK
WEDNESDAY MORNING. THIS COULD BE A MIXED BAG OF PRECIP TYPES. THE
REST OF THE DAY LOOKS CLOUDY WITH MODERATING TEMPERATURES AND
ANOTHER COLD FRONT APPROACHING QUICKLY FROM THE WEST. AS THIS COLD
FRONT MOVES THROUGH WEDNESDAY NIGHT...THERE MAY BE SOME RAIN SHOWERS
CHANGING TO SNOW SHOWERS. ANOTHER SHOT OF COLD AIR BEHIND THE FRONT
FOR THURSDAY AND FRIDAY.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
SNOW IS SLOWLY WINDING DOWN...BUT WILL CONTINUE FOR AT LEAST A
COUPLE OF MORE HOURS AT THE TAF SITES. BRIEF IMPROVEMENT TO VFR
CONDITIONS EXPECTED AFTER SUNRISE TODAY FOR THE VALLEY TAF
SITES...WITH CONTINUED MVFR AT KPSF. A VIGOROUS COLD UPPER LEVEL
TROUGH BRINGS ANOTHER CHANCE FOR SNOW LATER THANKSGIVING DAY TO
THE AREA WITH MVFR CONDITIONS EXPECTED AT ALL THE TAF SITES BY
SUNSET. A LIGHT ACCUMULATING SNOW IS AGAIN POSSIBLE LATER
THANKSGIVING DAY AND EVENING.
WINDS WILL BE NORTHWESTERLY TONIGHT AND DECREASE TO LESS THAN 10
KTS BY LATE TONIGHT...AND CONTINUE THROUGH THURSDAY.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...FZRA.
SUNDAY NIGHT: SLIGHT CHANCE OF SHRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SLEET.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THROUGH THE
WEEKEND.
ADDITIONAL LIGHT PRECIPITATION AMOUNTS ARE EXPECTED WITH BASIN
AVERAGES AT A TENTH OF AN INCH OR LESS EXPECTED.
MILDER TEMPS ARE POSSIBLE SUNDAY WITH SOME SNOW MELT. HOWEVER...
TEMPERATURES ARE EXPECTED TO COOL OFF QUICKLY DURING MONDAY WITH
THE PASSAGE OF A STRONG COLD FRONT.
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.
&&
.CLIMATE...
A RECORD SNOWFALL OF 9.6 INCHES WAS SET AT ALBANY NY YESTERDAY.
THIS BREAKS THE OLD RECORD OF 4.9 SET IN 1888. ALSO...THIS PLACES
ALBANY INTO ONE OF THE TOP 10 SNOWSTORMS FOR THE MONTH. WITH
ADDITIONAL SNOWFALL EXPECTED...WE WILL WATCH HOW MUCH ADDS UP TO
SEE WHERE WE FINISH UP BY THE END OF THE MONTH.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM/WASULA
LONG TERM...SND
AVIATION...SND/NAS
HYDROLOGY...KL/BGM/WASULA
CLIMATE...BGM/IAA
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
335 AM EST THU NOV 27 2014
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN AMPLIFIED UPPER LEVEL
PATTERN ACROSS THE CONUS CONSISTING OF LONGWAVE RIDGING OVER THE
INTER-MOUNTAIN WEST...AND DOWNSTREAM LONGWAVE TROUGHING TO THE EAST
OF THE CONTINENTAL DIVIDE. MOST OF THE INCLEMENT WEATHER ASSOCIATED
WITH THIS EASTERN CONUS TROUGH IS NOW OFF THE EASTERN SEABOARD OR
EXITING THE NEW ENGLAND AREA. THE TROUGH AXIS IS NOW PASSING OUR
LONGITUDE PUSHING THE PLUME OF DEEP TROPICAL MOISTURE FURTHER TO OUR
EAST WITH TIME. DEEP LAYER SUBSIDENCE/DRYING HAS NOW OVERSPREAD THE
NORTHERN AND CENTRAL PORTIONS OF THE FLORIDA PENINSULA. ONE FINAL
SHORTWAVE IMPULSE TO IMPACT OUR REGION IS CLEARLY VISIBLE IN WV
IMAGERY AS IT ROUNDS THE TROUGH BASE THROUGH THE TN VALLEY. THIS
IMPULSE WILL PROPEL A SECONDARY COLD FRONT THROUGH THE EASTERN GULF
AND FL PENINSULA TODAY.
WE SAW AN INCREDIBLE DRYING OF THE COLUMN ON WEDNESDAY BETWEEN THE
26/12Z KTBW SOUNDING WHICH HAD A PW VALUE OVER 1.8"...TO THE
27/00Z SOUNDING WHERE THE PW VALUE HAD DROPPED ALL THE WAY DOWN TO
0.17". HUGE DEWPOINT DEPRESSIONS GREATER THAN 40C WERE SAMPLED FROM
ALMOST THE SURFACE UP TO NEARLY 300MB. THIS 0.17" PW VALUE IS NEAR
(WITHIN A FEW HUNDREDTHS OF AN INCH) AN ALL TIME LOW FOR LATE
NOVEMBER. IN FACT...IT IS A RARE OCCASION THAT WE SEE PW VALUES
LOWER THAN THIS AT ANY TIME OF YEAR. THE ONLY CLOUDS TO SPEAK OF
THIS EARLY AM ARE SOME VERY THIN HIGH LEVEL CIRRUS STREAMING OVER
THE SOUTHERN PENINSULA ON THE PERIPHERY OF THE UPPER TROUGH AND
WITHIN THE RRQ OF AN IMPRESSIVE UPPER JET ALONG THE EASTERN
SEABOARD.
AS MENTIONED ABOVE...ANOTHER COLD FRONT IS QUICKLY APPROACHING THE
REGION FROM THE NORTHWEST. THE FRONT AS OF THE ISSUANCE OF THIS
DISCUSSION WAS PASSING INTO THE FLORIDA PANHANDLE ON ITS WAY TOWARD
OUR REGION. TEMPERATURES ACROSS THE REGION UNDER MOSTLY CLEAR SKIES
RANGE FROM THE MIDDLE 40S TO LOWER 50S SOUTH...TO THE UPPER 30S AND
LOWER 40S NORTH. NOT EXPECTING MUCH MORE OF A TEMPERATURE DROP OVER
THESE COOLER NATURE COAST ZONES AS THE THERMAL RIDGE AHEAD OF THE
APPROACHING FRONT BEGINS TO ARRIVE IN THE COMING HOURS.
&&
.SHORT TERM (TODAY THROUGH FRIDAY)...
TODAY...
UPPER TROUGH AXIS WILL MOVE TO THE EASTERN SEABOARD THROUGH THE DAY
WHILE A SECONDARY COLD FRONT MAKES A DRY PASSAGE ACROSS THE EASTERN
GULF AND FLORIDA PENINSULA. GENERALLY SPEAKING THIS FRONT WILL BE
ACCOMPANIED BY A WIND SHIFT...AND A QUICK INCREASE IN WINDS OVER THE
EASTERN GULF AND ALONG THE COAST. THOSE WITH PLANS NEAR THE BEACH
SHOULD EXPECT WINDS TO BECOME RATHER GUSTY FROM THE NORTHWEST FOR
THE AFTERNOON HOURS. HAVE HOISTED AN ELEVATED RISK OF RIP CURRENTS
FOR THE SECOND HALF OF THE DAY IN RESPONSE TO THIS INCREASING
ONSHORE FLOW FOR THE BEACHES OF PINELLAS...MANATEE...AND SARASOTA
COUNTIES. DESPITE THE COLD FRONTAL PASSAGE...TEMPERATURES TODAY WILL
BE SEASONABLE WITH 60S NORTH AND UPPER 60S TO AROUND 70S SOUTH. THE
DEVELOPING GUSTY WIND WILL MAKE IT FEEL COOLER THIS AFTERNOON...
ESPECIALLY NEAR THE COAST. CONDITIONS WILL TURN MUCH COOLER THIS
EVENING AS THE SUN BEGINS TO SET.
TONIGHT...
A CHILLY NIGHT SETTING UP IN THE WAKE OF THE FRONT. HIGH PRESSURE
WILL STILL BE WELL OFF TO THE NORTHWEST OF THE REGION WHICH WILL
KEEP THE GRADIENT TIGHT AND AT LEAST SOME WIND BLOWING THROUGH THE
NIGHT. WITH THE FORECAST HIGH POSITION...IT WILL BE DIFFICULT TO
DECOUPLE THE BOUNDARY LAYER...FOR EVEN OUR FAR NORTHERN ZONES. WITH
THIS IN MIND...RADIATIONAL COOLING WILL NOT BE MUCH OF A FACTOR
TONIGHT...BUT RATHER WILL BE LOOKING AT AN ADVECTION/DRAINAGE EVENT
FROM THE NORTH. GENERALLY SPEAKING THE MOS IS BIASED TOO COLD FOR
ADVECTION NIGHT...AND KEPT TEMPS AT OR JUST ABOVE THE MOS ENSEMBLES
FOR LOW TEMPERATURES. THIS RESULTS IN LOW TEMPERATURES RANGING FROM
AROUND 32 OVER INLAND LEVY COUNTY...TO THE UPPER 30S AND LOWER 40S
FOR THE I-4 CORRIDOR AND SOUTHWARD. NORMALLY WARMER SPOTS UNDER
NORTHEAST FLOW SUCH AS PINELLAS COUNTY AND THE SANIBEL REGION WILL
STAY IN THE MIDDLE TO UPPER 40S. IF THINGS WORK OUT THIS WAY THEN
FREEZE PRODUCTS WILL NOT BE NECESSARY...HOWEVER IT IS A CLOSE CALL
UP TOWARD LEVY COUNTY AND WILL NEED TO BE MONITORED CLOSELY WITH
FUTURE GUIDANCE RUNS. DID INCLUDE A MENTION OF PATCHY FROST FOR
PORTIONS OF THE NATURE COAST WHERE TEMPS IN THE LOWER/MID 30S ARE
FORECAST. CONDITIONS ARE EVEN BORDERLINE FOR FROST WITH A LIGHT WIND
AND DEWPOINT DEPRESSIONS OF 3-5 DEGREES LATE AT NIGHT. HOWEVER...A
FEW MORE SHELTERED AREA COULD STILL REALIZE A TOUCH OF FROST TOWARD
DAWN. WIND CHILLS WILL BE A CONCERN WITH WIDESPREAD READINGS IN THE
30S EARLY FRIDAY MORNING...AND EVEN SOME UPPER 20S FOR THE NATURE
COAST.
FRIDAY..
HIGH PRESSURE AT THE SURFACE BUILDS INTO NORTHERN FLORIDA WHILE THE
UPPER LEVEL PATTERN BEGINS TO FURTHER FLATTEN OUT OVERHEAD. FRIDAY
IS LOOKING TO BE A DRY AND COOL DAY WITH HIGH TEMPERATURES
RECOVERING BY MID AFTERNOON TO AROUND 60 FOR CHIEFLAND...LOWER 60S
ALONG THE I-4 CORRIDOR AND MID/UPPER 60S DOWN TOWARD FORT MYERS.
HOWEVER...SHOULD BE LOOKING AT LOTS OF SUNSHINE AND A BIT LESS WIND
TO HELP THE OVERALL TEMPERATURE FEEL FOR THE SECOND HALF OF THE DAY.
HAVE A SAFE AND HAPPY THANKSGIVING EVERYONE!
&&
.LONG TERM (SATURDAY THROUGH NEXT WEDNESDAY)...
THE PERIOD BEGINS WITH AN UPPER TROUGH ACROSS WESTERN CANADA...AN
UPPER RIDGE OVER THE U.S ROCKIES...A SHORTWAVE TROUGH ALOFT
NORTHWEST MEXICO...AND A TROUGH OVER ATLANTIC WATERS. AT THE SURFACE
A FRONTAL BOUNDARY STRETCHED FROM THE PACIFIC NORTHWEST TO THE
NORTHERN U.S. PLAINS WHILE HIGH PRESSURE SPRAWLED FROM THE CENTRAL
AND EASTERN GULF OF MEXICO TO THE LOWER GREAT LAKES.
WITH TIME THE CANADIAN TROUGH ROTATES DOWN ACROSS THE PACIFIC
NORTHWEST THEN OVER THE NORTHERN PLAINS WHILE THE MEXICAN SHORT WAVE
TROUGH TRACKS EAST. IN RESPONSE THE UPPER RIDGE FLATTENS AND SLIDES
ALONG THE GULF COAST REGION THROUGH THE SOUTHEAST U.S. AND OUT OVER
THE ATLANTIC BY THE MIDDLE OF NEXT WEEK. MEANWHILE THE FRONTAL
BOUNDARY SHIFTS EASTWARD...STRUNG OUT FROM THE WESTERN GULF COAST TO
NEW ENGLAND FOR THE START OF NEXT WEEK AS HIGH PRESSURE BUILDS OVER
THE CENTRAL PLAINS. THE HIGH PRESSURE ORIGINALLY FROM THE GULF TO
THE GREAT LAKES TRACKS OUT OVER THE ATLANTIC BUT CONTINUES TO RIDGE
BACK THROUGH THE EAST AND CENTRAL GULF COAST. DURING THE EARLY PART
OF THE WEEK THE PLAINS HIGH MOVES EAST...BRIDGING THE BY NOW
DECAYING FRONTAL BOUNDARY...AND REINFORCING THE RIDGE FROM THE
ATLANTIC.
THE UPPER RIDGING MOVING BY WILL BE THE DOMINATE FACTOR WITH A
DRY AIRMASS KEEPING THE FORECAST RAIN FREE. TEMPERATURES INITIALLY
NEAR OR JUST BELOW NORMAL GRADUALLY WARM TO NORMAL TO SLIGHTLY
ABOVE. SURFACE HIGH PRESSURE NORTH OF THE AREA WILL MAINTAIN A TIGHT
ENOUGH PRESSURE GRADIENT FOR NORTHEASTERLY AND EASTERLY
WINDS...ROBUST AT TIMES ESPECIALLY ON THE GULF.
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD WITH WINDS
GENERALLY NORTHWEST TO NORTH.
&&
.MARINE...
A SECONDARY COLD FRONT WILL QUICKLY PASS THROUGH THE REGION THIS
MORNING AND EARLY AFTERNOON. WINDS AND SEAS WILL QUICKLY BUILD TO
ADVISORY LEVELS IN THE WAKE OF THIS FRONT FOR LATER THIS AFTERNOON
THROUGH FRIDAY MORNING. A FEW WIND GUST APPROACHING GALE FORCE CAN
NOT BE RULED OUT TONIGHT AS WELL. WINDS AND SEAS WILL GRADUAL
SUBSIDE ON FRIDAY AS HIGH PRESSURE BUILD TO THE NORTH OF THE REGION.
THIS RIDGE OF HIGH PRESSURE WILL REMAIN IN PLACE TO OUR NORTH
THROUGH THE UPCOMING WEEKEND AND KEEP WINDS ACROSS THE EASTERN GULF
OF MEXICO FROM AN OFFSHORE EAST TO NORTHEAST DIRECTION.
&&
.FIRE WEATHER...
ANOTHER COLD FRONT WILL MAKE A DRY PASSAGE ACROSS THE REGION TODAY
AND BE FOLLOWED BY HIGH PRESSURE BUILDING TO OUR NORTH FOR THE
DURATION OF THE FORECAST PERIOD. RELATIVE HUMIDITY VALUES ARE
FORECAST TO APPROACH OR BRIEFLY DROP BELOW 35 PERCENT FOR MUCH OF
THE REGION THIS AFTERNOON...AND ONCE AGAIN ON FRIDAY AFTERNOON.
ERC VALUES ARE CURRENTLY ALL BELOW 27 WHICH WILL KEEP RED FLAG
CONDITIONS FROM BEING ACHIEVED BOTH DAYS.
NO SIGNIFICANT FOG IS EXPECTED TO IMPACT THE REGION THE NEXT COUPLE
OF NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 68 42 63 47 / 0 0 0 0
FMY 72 44 68 51 / 0 0 0 0
GIF 68 40 64 47 / 0 0 0 0
SRQ 70 43 65 48 / 0 0 0 0
BKV 66 34 61 39 / 0 0 0 0
SPG 66 48 62 53 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...RIP CURRENT RISK FROM NOON EST TODAY THROUGH THIS EVENING
FOR COASTAL MANATEE-COASTAL SARASOTA-PINELLAS.
GULF WATERS...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO
1 PM EST FRIDAY FOR BONITA BEACH TO ENGLEWOOD OUT 20 TO
60 NM-ENGLEWOOD TO TARPON SPRINGS OUT 20 TO 60 NM.
SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 10 AM EST
FRIDAY FOR BONITA BEACH TO ENGLEWOOD OUT 20 NM-
ENGLEWOOD TO TARPON SPRINGS OUT 20 NM-TARPON SPRINGS
TO SUWANNEE RIVER OUT 20 NM-TARPON SPRINGS TO
SUWANNEE RIVER OUT 20 TO 60 NM.
SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 AM EST
FRIDAY FOR CHARLOTTE HARBOR AND PINE ISLAND SOUND-
TAMPA BAY WATERS.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/AVIATION/FIRE WX...MROCZKA
LONG TERM...RUDE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1053 PM MST WED NOV 26 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 123 PM MST WED NOV 26 2014
AS OF 2 PM CST...1 PM MST...SKIES ACROSS THE TRI-STATE REGION VARIED
FROM MOSTLY CLEAR TO OVERCAST. TEMPERATURES WERE IN THE 40S WHERE
CLOUDS HAVE BROKEN UP AND IN THE LOW TO UPPER 30S WHERE PERSISTENT
CLOUDS REMAIN. WINDS WERE FROM THE NORTH AT 10 TO 15 MPH AND ON A
GRADUAL WEAKENING TREND. WSR-88D RADAR DATA HAS NOTED A DOWNWARD
TREND IN RADAR REFLECTIVITIES AS THE BAND OF LIGHT SNOW SHOWERS
FINALLY BEGINS TO DIMINISH. SNOW APPEARS TO BE THE RESULT OF LOW
LEVEL FRONTOGENESIS OVER NORTHEAST COLORADO AS NO MAJOR DISTURBANCES
HAVE BEEN OBSERVED BY WATER VAPOR IMAGERY.
FOR THE REST OF THE AFTERNOON AND TONIGHT...MAIN FORECAST CONCERN IS
DECREASING SNOW SHOWER ACTIVITY THROUGH THE AFTERNOON WITH POSSIBLE
BRIEF REDEVELOPMENT THIS EVENING. LATEST RAP GUIDANCE/HRRR GUIDANCE
SEEMS TO BE HANDLING THIS SITUATION BEST SO HAVE LEANED ON THESE
SOLUTIONS. RAP FORECAST SOUNDINGS INDICATE THAT THE ICE CRYSTAL
GROWTH ZONE LOSES SATURATION THIS AFTERNOON...LEADING TO A DECREASE
IN PRECIPITATION. THAT TREND IS ALREADY BEING REALIZED. RAP
SOUNDINGS THEN INDICATE ONE MORE PUSH OF MOISTURE IN THE ICE CRYSTAL
GROWTH ZONE LATER THIS EVENING BEFORE THE ENTIRE ATMOSPHERIC PROFILE
DESATURATES. ATTEMPTED TO SHOW THIS UP AND DOWN TREND WITH THE POPS
THROUGH THIS EVENING AND THEN FORECAST DRY WEATHER AFTER MIDNIGHT.
SKIES GRADUALLY CLEAR LATE TONIGHT WITH A QUICK DROP IN TEMPS ONCE
CONDITIONS ARE CONDUCIVE FOR RADIATIONAL COOLING.
FOR THANKSGIVING DAY...OVERALL CALM WEATHER IS ANTICIPATED WITH NO
PRECIPITATION EXPECTED. ATMOSPHERIC PROFILE BECOMES QUITE DRY BY
AFTERNOON...ESPECIALLY IN THE LOW LEVELS...AS DRY AIR ADVECTION
CONTINUES FROM THE SOUTHWEST. A LEE TROUGH DEEPENING OVER CENTRAL
COLORADO SHALL LEAD TO PERSISTENT SOUTHWEST FLOW THROUGHOUT THE DAY.
WARM 850 MB TEMPS ALSO ADVECT IN SO EXPECTING A WARM...ABOVE NORMAL
DAY. ONE THING THAT IS INTERESTING ABOUT TOMORROW IS FORECAST
SOUNDINGS INDICATE THAT A PERSISTENT INVERSION NEAR THE SURFACE MAY
PREVENT SOME STRONGER WIND GUSTS ALOFT FROM BEING REALIZED AT THE
SURFACE. WILL NEED TO WATCH THIS CAREFULLY AS LOW RELATIVE HUMIDITY
WILL BE PRESENT OVER CHEYENNE AND KIT CARSON COUNTIES IN COLORADO
AND SHERMAN...WALLACE...GREELEY AND POSSIBLY WICHITA COUNTIES IN
KANSAS. OVERALL...KEPT FORECAST WINDS LIGHT BUT NERVOUS ABOUT
STRONGER WINDS ALOFT MIXING DOWN. IF WINDS ARE REALIZED...A FIRE
WEATHER HIGHLIGHT MAY BE REQUIRED.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 1204 PM MST WED NOV 26 2014
BROAD ZONAL FLOW WILL PERSIST THROUGH SATURDAY ACROSS THE CENTRAL
CONUS OVER A LOW AMPLITUDE RIDGE CENTERED OVER THE DESERT
SOUTHWEST. THIS WILL RESULT IN DRY CONDITIONS AND MUCH ABOVE
NORMAL TEMPERATURES. RELATIVE HUMIDITY WILL DROP TO NEAR CRITICAL
FIRE WEATHER VALUES EACH AFTERNOON...HOWEVER WIND FORECASTS ARE
RELATIVELY LIGHT AND NO FIRE WEATHER HIGHLIGHTS ARE ANTICIPATED. A
NORTHERN STREAM SHORTWAVE WILL SUPPORT A SURFACE COLD FRONT WHICH
WILL MOVE THROUGH THE CENTRAL HIGH PLAINS SATURDAY NIGHT. SYNOPTIC
SCALE FORCING FOR PRECIPITATION WILL REMAIN NORTH OF THE LOCAL
AREA AND FROPA WILL LIKELY BE DRY. TEMPERATURES ON SUNDAY WILL BE
CLOSER TO NORMAL...THEN COOL TO BELOW NORMAL ON MONDAY WHICH WILL
BE THE COLDEST DAY OF THIS PERIOD. TEMPERATURES BOUNCE BACK TO
ABOVE NORMAL ON TUESDAY UNDER SHORTWAVE RIDGING WITH CONTINUED DRY
CONDITIONS. FINALLY...ON WEDNESDAY A SHORTWAVE TROUGH IN THE
SOUTHERN STREAM WILL MOVE OUT OF THE SOUTHERN ROCKIES AND EMERGE
ONTO THE ADJACENT PLAINS...WITH A CHANCE FOR RAIN AND SNOW. TIMING
AND AMOUNTS WITH THE SYSTEM STILL VERY UNCERTAIN WITH SIGNIFICANT
MODEL DIFFERENCES AT THIS TIME RANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1051 PM MST WED NOV 26 2014
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD AT MCK AND
GLD. WINDS WILL TURN FROM THE SOUTH-SOUTHEAST TO THE SOUTHWEST
THROUGH THE DAY ON THURSDAY AS THE SURFACE HIGH PRESSURE AREA
MOVES EAST AND THE LEE SURFACE DEEPENS ALONG THE FRONT RANGE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...RRH
LONG TERM...024
AVIATION...LOCKHART
AREA FORECAST DISCUSSION
NWS JACKSON KY
1229 AM EST THU NOV 27 2014
.UPDATE...
ISSUED AT 1104 PM EST WED NOV 26 2014
SEVERAL CHANGES WERE MADE BASED ON CURRENT CONDITIONS AND TRENDS.
FIRST...THE POPS. OVERALL...THE RAINFALL COVERAGE SEEMS TO MATCH UP
WELL WITH THE ONGOING FORECAST FOR POPS. HOWEVER...THE COVERAGE OF
THIS SYSTEM HAS NOT REACHED AS FAR NORTH AS WAS ORIGINALLY EXPECTED.
AS A RESULT...TONED BACK SOME OF OUR SLIGHT CHANCE POPS ACROSS THE
NORTHERN CWA FOR THE NEXT COUPLE OF HOURS. ONCE MORE PRECIP MOVES
INTO THE AREA...ALLOWED FOR SOME SLIGHT CHANCES TO EXPAND ACROSS THE
REMAINDER OF THE CWA.
ALSO...LOOKING AT THE ONGOING FORECASTED DIURNAL CURVE FOR THE
REMAINDER OF THE NIGHT...IT SHOWED TEMPS RISING ACROSS PORTIONS OF
THE FAR EASTERN CWA OVER THE NEXT FEW HOURS...BEFORE DROPPING NEAR
DAWN. MEANWHILE...CURRENT OBSERVATIONS ARE SHOWING TEMPERATURES
EITHER REMAINING STEADY OR DROPPING ACROSS THE CWA. THIS WAS CREATING
SOME DISCREPANCIES IN THE NEAR TERM TEMPERATURE FORECAST...AND WOULD
CONTINUE TO DO SO THROUGHOUT THE NIGHT...EVEN WHEN BLENDING IN THE
LATEST NEAR TERM OBSERVATIONS. ENDED UP ADJUSTING THE DIURNAL CURVE
FOR A MORE STEADY DOWNWARD TREND THROUGHOUT THE NIGHT.
AS SUCH...THIS CHANGED THE WEATHER TYPES SOMEWHAT THROUGHOUT THE
NIGHT. ULTIMATELY IT ALLOWED FOR BETTER MATCHING UP WITH NEIGHBORING
OFFICES FOR CHANGE OVER FROM RAIN TO SNOW. BUT GIVEN THE LIGHT NATURE
OF THIS SYSTEM SO FAR...AND THE FACT THAT MUCH OF THIS SNOW WILL MIX
WITH RAIN THROUGH THE MAJORITY OF THE NIGHT...FELT THAT SNOW TOTALS
ULTIMATELY SEEMED REASONABLE AND DID NOT NEED TO BE CHANGED. STILL
EXPECTING BEST SNOW ACCUMULATIONS AROUND DAWN WHEN TEMPS ARE THE
COLDEST. BUT AT THIS POINT THE SYSTEM WILL BE DYING DOWN AND MOVING
OUT...AND DAYTIME TEMPS WILL WORK TO QUICKLY MELT ANYTHING THAT HAS
ACCUMULATED.
UPDATE ISSUED AT 655 PM EST WED NOV 26 2014
BASED ON THE LATEST SATELLITE DATA...WENT AHEAD AND INCREASED CLOUD
COVER ACROSS THE CWA...WITH CLOUDS EXPECTED TO CONTINUE THICKENING
THROUGHOUT THE EVENING AND OVERNIGHT. SOME OF THESE CLOUDS ARE
HIGH...BUT ARE COVERING A LARGE MAJORITY OF THE CWA...SO WENT AHEAD
AND INCLUDED BKN CLOUDS FOR THE REST OF THE EVENING.
CURRENTLY...TEMPERATURE READINGS ARE STILL IN THE UPPER 30S AND LOW
40S...WITH DEW POINT DEPRESSIONS 10 TO 20 DEGREES. ALTHOUGH WE ARE
GETTING A FEW RADAR RETURNS IN THE FAR SW PORTION OF THE CWA...IT IS
UNLIKELY THAT ANY OF THIS MOISTURE WILL MAKE IT TO THE SURFACE FOR AT
LEAST A FEW MORE HOURS. AND GIVEN THE CURRENT TEMPERATURES...ONCE
PRECIP DOES FALL...IT SHOULD BE IN THE FORM OF RAIN. LATEST FORECAST
SOUNDINGS FOR BOTH THE NAM AND GFS ARE STILL SHOWING TEMPERATURES
REMAINING ABOVE FREEZING THROUGH AT LEAST 6Z...IF NOT LONGER IN SOME
LOCATIONS...AND THEN HOVERING RIGHT AROUND THE FREEZING MARK
THEREAFTER UNTIL WARMING AGAIN AFTER DAY BREAK. HOWEVER...ACCORDING
TO THE LATEST WPC WINTER WEATHER ACCUMULATION FORECAST ISSUED AROUND
1630Z...2 TO 4 INCHES IS STILL EXPECTED IN THE SOUTHERN PORTION OF
THE CWA. IN OTHER WORDS...SOME GOOD WET BULBING PROCESSES ARE GOING
TO HAVE TO TAKE PLACE THIS EVENING IN ORDER FOR THIS TO PAN OUT. AS
SUCH...THERE HASN/T BEEN ENOUGH EVIDENCE TO CHANGE THE CURRENT
FORECAST SNOW TOTALS. STILL EXPECT WHAT DOES FALL TO MAINLY
ACCUMULATE ON THE GRASSY AND ELEVATED SURFACES...AND TURN INTO A
SLUSHY MIX OF RAIN AND SNOW ON THE ROADWAYS BEFORE QUICKLY MELTING
OFF.
WILL CONTINUE TO MONITOR TEMPS AND PRECIPITATION UPSTREAM AS THIS
SYSTEM NEARS AND BEGINS IMPACTING THE REGION...IN CASE ANY
MODIFICATIONS TO THE CURRENT SNOW/RAIN FORECAST NEED TO BE MADE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 315 PM EST WED NOV 26 2014
...SOME SLUSHY SNOW ACCUMULATIONS POSSIBLE LATE TONIGHT OVER SOUTHERN
PARTS OF EAST KENTUCKY...
19Z SFC ANALYSIS SHOWS EAST KENTUCKY IN BETWEEN TWO AREAS OF LOW
PRESSURE. TO THE EAST...A COASTAL LOW IS NOW PASSING NORTH OF CAPE
HATTERAS...WHILE A MORE MODERATE STRENGTH SFC LOW IS LOCATED OVER
CENTRAL MISSOURI ON ITS PATH SOUTHEAST INTO THE TENNESSEE VALLEY. IN
THE GAP BETWEEN THESE SYSTEMS ENOUGH CLEARING TOOK PLACE FOR MOST OF
THE AREA THAT TEMPERATURES CLIMBED INTO UPPER 40S AND LOWER 50S THIS
AFTERNOON. WINDS ARE GENERALLY LIGHT WHILE DEW POINTS ARE FOUND IN THE
MID AND UPPER 20S...THOUGH WITH SOME 30S IN THE FAR EAST.
THE MODELS ARE IN PRETTY GOOD AGREEMENT...NOW THAT THE GFS IS
BREAKING TOWARD THE ECMWF AND NAM...ALOFT WITH THE CLIPPER SYSTEM
DROPPING INTO THE TENNESSEE VALLEY TONIGHT. THEY ALL SHOW THE
ENERGY...ASSOCIATED WITH EASTERN PORTION OF THE LARGE TROUGH IN
PLACE OVER THE OHIO VALLEY...LIFTING NORTHEAST INTO EASTERN NEW
ENGLAND BY THURSDAY MORNING. AT THE SAME TIME...A SECONDARY BATCH OF
ENERGY WITHIN THE LARGER TROUGH WILL RIDE SOUTHEAST FROM THE EAST
CENTRAL PLAINS TO THE TENNESSEE VALLEY...THOUGH SHEARING AS IT PASSES
BY KENTUCKY TO THE SOUTH TONIGHT. FOLLOWING THIS...THE WHOLE TROUGH
BODILY MOVES OUT OF THE REGION AND RISING HEIGHTS FOLLOW. HAVE
FOLLOWED A GENERAL MODEL BLEND FOR THE SHORT TERM PORTION THE
FORECAST WITH SOME CAUTIOUS FAVORING OF THE HIGHER RESOLUTION NAM12
AND HRRR FOR WX DETAILS.
SENSIBLE WEATHER WILL FEATURE A QUIET EVENING AS HIGH CLOUDS OVERTAKE
THE SKY AND LOWER WITH TIME. A WEAKENING AREA OF LOW PRESSURE WILL
SLIDE SOUTH THROUGH SOUTHERN KENTUCKY AND INTO EASTERN TENNESSEE.
THIS WILL BRING WITH IT A NARROW BAND OF PCPN CAPABLE OF BECOMING
SNOW GIVEN THE EXPECTED WET BULB EFFECT WHEN IT STARTS COMING DOWN
MODERATELY ACROSS OUR SOUTHERN COUNTIES. HOWEVER...SFC TEMPERATURES
WILL BE NEAR 32 DEGREES AT THEIR COLDEST LIKELY PREVENTING MUCH
ACCUMULATION ON ANYTHING MORE THAN GRASSY AND ELEVATED SURFACES AND
THEN MAINLY ON THE RIDGES AS THE VALLEYS REMAIN A MIX OF RAIN AND
SNOW. THIS IS A DISTURBINGLY SIMILAR SITUATION AS COMPARED TO LAST
NIGHT IN THE EAST WHERE THE HEAVIER PCPN STAYED JUST OFF TO THE EAST.
THESE SMALL SCALE DETAILS MAKE ALL THE DIFFERENCE IN MARGINAL
SITUATIONS AS THIS. HOWEVER...CANNOT RULE OUT A HEAVIER BURST OR TWO
OF SNOW THAT COULD CAUSE A SLUSHY ACCUMULATION ON THE ROADS. THIS
SHOULD NOT LAST LONG...THOUGH...AS ROAD TEMPERATURES ARE CURRENTLY IN
THE 40S AND 50S AND WILL ONLY SLOWLY FALL WITH THE PCPN TONIGHT. HAVE
ISSUED AN SPS TO DEAL WITH THE POTENTIAL FOR A SLUSHY INCH OF SNOW
THAT SHOULD HAVE A MINIMAL IMPACT ON TRAVELERS TONIGHT. THE LIGHT
SNOW/RAIN PULLS OUT OF THE AREA EARLY THURSDAY WITH COOLER
TEMPERATURES TO FOLLOW AS HIGH PRESSURE MOVES THROUGH THE SOUTHERN
APPALACHIANS INTO FRIDAY MORNING.
ONCE AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR T/TD/WINDS
THROUGH THE NEXT 24 HOURS AND THE SUPERBLEND THEREAFTER. DID MAKE
SOME TERRAIN BASED ADJUSTMENTS TONIGHT INTO THURSDAY MAINLY TO LOWER
THE RIDGES IN OUR SOUTHERN COUNTIES DUE TO THE PCPN AND ANTICIPATED
WET BULBING. AS FOR POPS...ENDED UP CLOSE TO A BLEND OF THE DRIER MAV
AND WETTER MET NUMBERS TONIGHT INTO THURSDAY MORNING AND THEN
MATCHED THEIR DRY CONSENSUS INTO FRIDAY MORNING.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 245 PM EST WED NOV 26 2014
THE SYNOPTIC PATTERN THROUGH THE LONG TERM PERIOD WILL FEATURE A
PROGRESSIVE FLOW ALOFT WITH A GENERAL SOUTHWEST FLOW IN THE LOW
LEVELS AS AN ELONGATED AREA OF SURFACE HIGH PRESSURE STRETCHES OUT
FROM THE DEEP SOUTH EASTWARD INTO THE WESTERN ATLANTIC. A COLD FRONT
WILL DROP SOUTH INTO THE REGION ON MONDAY...AND THEN STALL OUT IN
OUR VICINITY AS THE SPONSORING UPPER TROUGH PASSES BY TO THE NORTH.
A SECOND TROUGH WILL THEN FOLLOW A SIMILAR TRACK AND PASS BY TO OUR
NORTH MIDWEEK. FORECAST MODELS DIFFER ON THE STRENGTH OF THIS
SHORTWAVE AND THE RESULTING IMPACT IT WILL HAVE ON THE FRONT
AND FORECASTER CONFIDENCE DROPS BELOW AVERAGE BY THE END OF THE
PERIOD.
OUR SENSIBLE WEATHER WILL FEATURE A MODERATING TREND OVER THE
THANKSGIVING HOLIDAY WEEKEND. UNFORTUNATELY...THE WARMING TEMPS WILL
BE ACCOMPANIED BY INCREASING CLOUDS AND A FEW SHOWERS BY SATURDAY
NIGHT INTO THE DAY ON SUNDAY AS LOW LEVEL MOISTURE INCREASES. RAIN
CHANCES THEN INCREASE DRAMATICALLY SUNDAY NIGHT INTO MONDAY AS THE
FRONT DROPS INTO THE AREA. BEYOND MONDAY...TEMPS AND RAIN CHANCES
ARE PROBLEMATIC DUE TO THE MODEL DIFFERENCES REGARDING THE PLACEMENT
OF THE FRONT. SIDING WITH A MODEL BLEND YIELDS NEAR NORMAL TEMPS AND
A CHANCE OF RAIN EACH PERIOD THROUGH WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1228 AM EST THU NOV 27 2014
LOZ AND SME ARE ALREADY EXPERIENCING MVFR CIGS WITH LIGHT RAIN.
JKL AND SJS CAN EXPECT THE SAME TO OCCUR BETWEEN 7 AND 8Z AS AN AREA
OF RAIN SHOWERS MOVE ACROSS THE AREA. THE RAIN WILL BEGIN TO MIX WITH
SNOW AT THE TAF SITES AROUND 8Z. THE PRECIPITATION IS EXPECTED TO END
AT THE TAF SITES BETWEEN 12 AND 13Z THIS MORNING. LOW LEVEL CLOUDS
AND MVFR CIGS ARE EXPECTED TO LAST UNTIL AROUND 14Z. CONDITIONS
SHOULD IMPROVE TO VFR WITH CIGS OF 3-4K BY 15 OR 16Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...ABE
AVIATION...AR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
127 AM EST THU NOV 27 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 510 PM EST WED NOV 26 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS CONTINUE TO SHOW AN AMPLIFIED
PATTERN ACROSS NAMERICA WITH A RIDGE ALONG/JUST OFF THE W COAST...A
TROF EXTENDING FROM NCNTRL CANADA TO THE GULF OF MEXICO AND A RIDGE
OVER THE WRN ATLANTIC. A SHORTWAVE TROF SWINGING SE THRU NRN
ONTARIO/NRN MN IS PRODUCING SOME -SN FROM NW WI ACROSS WRN UPPER MI
INTO NRN ONTARIO. AT THE SFC...SHARPENING TROF RUNS FROM NEAR KIWD
TO JUST S OF KCMX AND THEN NE ACROSS ERN LAKE SUPERIOR. MDT TO HVY
LAKE ENHANCED SNOW IS SPREADING INTO WRN UPPER MI IN ASSOCIATION
WITH THE TROF. OFF TO THE NW...STRONG SFC HIGH PRES ACROSS
MANITOBA/SASKATCHEWAN IS BUILDING S AND E INTO THE NRN PLAINS.
PERIOD OF LAKE ENHANCED SNOW IS EXPECTED TONIGHT UNDER HEIGHT
FALLS/DEEP LAYER QVECTOR CONVERGENCE WITH SHORTWAVE SWINGING ACROSS
THE UPPER LAKES. BEST...MOST PERSISTENT LOW-LEVEL CONVERGENCE IS
INDICATED OVER THE FAR W. SO...MOST SUSTAINED MDT TO AT TIMES HVY
SNOW WILL OCCUR OVER THE FAR W FROM THE PORCUPINE MTNS TO KIWD. WITH
DGZ FALLING INTO THE LOW-LEVELS WHERE UPWARD MOTION IS FOCUSED...
EXPECT SNOW TO WATER RATIOS TO INCREASE INTO THE 20-30 TO 1 RANGE
TONIGHT. A LITTLE CONCERNED THAT THE UPWARD MOTION IS ONLY DEPICTED
IN THE LOWEST LEVELS THIS EVENING...SUGGESTING LITTLE OVERALL
SYNOPTIC SUPPORT WITH PASSING SHORTWAVE. THIS MAY TEND TO LIMIT
COVERAGE OF HVY SNOW TO ONLY THE AREAS WHERE LOW-LEVEL CONVERGENCE
IS FOCUSED. AS IT STANDS NOW...SITUATION APPEARS TO BE A MARGINAL
WARNING EVENT WITH WARNING THRESHOLDS ONLY POTENTIALLY BEING MET IN
A FEW LOCALIZED AREAS (8 INCHES OR MORE IN 12HRS OR 12 OR MORE IN
24HRS). LARGE PORTIONS OF ONTONAGON/GOGEBIC COUNTIES WILL PROBABLY
FALL IN THE 4 TO 7 INCH SNOWFALL RANGE. OF NOTE...THERE IS A FAIRLY
CONSISTENT SIGNAL AMONG MOST OF THE HIGH RES MODEL GUIDANCE FOR THE
HEAVIEST SNOW TO AFFECT LOCATIONS JUST W OF KIWD. WILL BE
INTERESTING TO SEE IF THAT INDEED DOES HAPPEN. OVER THE KEWEENAW...
SNOWFALL HAS NOT BEEN ESPECIALLY NOTEWORTHY WITH SFC TROF PASSAGE
WHICH IS WHEN THE HEAVIEST SNOWFALL WOULD LIKELY OCCUR. WITH A
DECENT LOW-LEVEL CONVERGENCE SIGNAL LACKING TONIGHT...CONSIDERED
DROPPING ADVY...BUT WILL HOLD OFF FOR NOW WITH POTENTIAL FOR SNOW TO
STILL PICK UP FOR A TIME THIS EVENING DURING THE PERIOD OF SYNOPTIC
FORCING. TO THE E...LONGER FETCH/BETTER TERRAIN ENHANCEMENT WILL
LEAD TO ANOTHER AREA OF HEAVIER SNOW DEVELOPING OVER NCNTRL UPPER MI
SPREADING FROM BARAGA COUNTY/FAR NRN MARQUETTE COUNTY EARLY THIS
EVENING TO ALGER COUNTY LATE EVENING. LOOKS LIKE SOLID ADVY AMOUNTS
FROM THE HURON MTNS TO NEGAUNEE AND EAST INTO WRN ALGER COUNTY.
POTENTIAL IS THERE FOR LOCALIZED WARNING AMOUNTS GIVEN THE
INCREASING SNOW TO WATER RATIOS AND THE LIKLIHOOD OF A LAKE NIPIGON
INITIATED DOMINANT BAND LATER TONIGHT INTO THE MORNING HRS THAT
WOULD LIKELY IMPACT LOCATIONS SOMEWHERE FROM AROUND BIG
BAY/MARQUETTE TO AROUND THE SHOT POINT AREA. IF SUCH A BAND DOES
DEVELOP AND BECOME STATIONARY FOR SEVERAL HRS...WARNING AMOUNTS MAY
BE ACHIEVED. BLSN WILL ALSO BE AN ISSUE IN THE OPEN AREAS ALONG LAKE
SUPERIOR WHERE WINDS WILL GUST OVER 30 MPH. WHILE THERE MAY BE A
BRIEF PERIOD OF HEAVIER SNOW OVER LUCE COUNTY WITH TROF PASSAGE...
SETUP AFTER TROF PASSAGE IS NOT FAVORABLE FOR ADVY SNOWFALL AMOUNTS
IN THAT AREA. ACROSS THE REST OF THE AREA...EXPECT SOME -SN FOR A
TIME TONIGHT. SOME OF THE LES OFF LAKE SUPERIOR WILL REACH NRN DELTA
AND SRN SCHOOLCRAFT COUNTIES TO PROVIDE AN INCH OR TWO OF SNOWFALL.
ON THANKSGIVING DAY...FCST SOUNDINGS SHOW INVERSIONS AT A LOW 4KFT
TO START THE DAY. LOW-LEVEL FLOW TRENDS ANTICYCLONIC DURING THE
DAY...ESPECIALLY SO OVER WRN LAKE SUPERIOR AS SFC HIGH PRES RIDGE
WILL EXTEND FROM THE MID MISSISSIPPI VALLEY N THRU WRN UPPER MI/WRN
LAKE SUPERIOR BY 00Z FRI. THESE 2 FACTORS COMBINED WITH RISING
HEIGHTS/LARGE SCALE SUBSIDENCE/QVECTOR DIVERGENCE WILL LIMIT LES
INTENSITY AND WILL RESULT IN LES DIMINISHING FROM W TO E THRU THE
DAY. IN FACT OVER THE FAR W...LES WILL END LATE IN THE AFTN AROUND
KIWD AS FLOW BACKS SW. THE ONE POSTIVE FACTOR FOR THE LES ON
THANKSGIVING DAY IS THAT THE DGZ WILL OCCUPY MOST OF THE CONVECTIVE
LAYER TO FLUFF UP SNOW ACCUMULATIONS. SO...DESPITE THE NEGATIVES
LEADING TO MOSTLY LIGHT LES ON THE WHOLE...MIGHT BE ABLE TO FLUFF UP
3-4 INCHES OF SNOW WHERE LES IS MOST PERSISTENT. THE GREATEST
ACCUMULATIONS WILL OCCUR E OF MARQUETTE WHERE LOW-LEVEL FLOW IS MORE
CYCLONIC THRU THE EARLY PART OF THE DAY AND WHERE LAKE NIPIGON
PRECONDITIONING WILL COME INTO PLAY. AWAY FROM THE MAIN LES...
SCT -SHSN/FLURRIES ARE POSSIBLE AT TIMES...EXCEPT OVER THE FAR
SCNTRL. TEMPS WILL BE UNSEASONABLY COLD ON THANKSGIVING DAY AS 850MB
THERMAL TROF (AROUND -20C) PASSES ACROSS THE AREA. EXPECT HIGHS
MOSTLY IN THE LOW/MID TEENS...TO AROUND 20F ALONG LAKE SUPERIOR AND
E. RECORD LOW MAX TEMP OF 18F HERE AT NWS MQT WILL FALL. IF TEMP
DOESN`T REACH 14F...IT WILL BE THE COLDEST MAX TEMP FOR SO EARLY IN
THE SEASON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM EST WED NOV 26 2014
THU NIGHT...THE LINGERING LES WILL DIMINISH AS THE SFC RIDGE AXIS
SLIDES THROUGH THE WRN LAKES AND LOW LEVEL WINDS BACK TO THE SW.
WITH LIGHT WINDS AND A PERIOD OF CLEARING OVER THE INTERIOR WEST
DURING THE EVENING...TEMPS WILL DROP QUICKLY TO MINS BELOW GUIDANCE
BEFORE RECOVERING OVERNIGHT AS CLOUDS MOVE IN. MODELS WERE
CONSISTENT IN BRINGING POTENTIAL FOR SOME LIGHT SNOW INTO THE WEST
LATE WITH THE DEVELOPING WAA PATTERN.
FRI...SNOW IS EXPECTED TO SPREAD ACROSS THE REGION WITH FAVORABLE
MOISTURE ADVECTION AND ISENTROPIC LIFT THROUGH THE 850-700 MB
FRONTAL ZONE. 3 G/KG MOISTURE AVAILABLE IN THE 285K-295K LAYER
DURING THE PERIOD OF STRONGEST LIFT IS CONSISTENT WITH POTENTIAL FOR
2 TO 4 INCHES OF SNOW WITH MODELS CONSENSUS QPF OF 0.10 TO 0.20
INCHES AND SLR VALUES FROM AROUND 15/1-20/1. THERE IS STILL SOME
UNCERTAINTY WHERE THE BAND OF HEAVIER SNOW WILL DEVELOP AS THE 12Z
NAM BRINGS GREATER AMOUNTS OF PCPN INTO SRN UPPER MI COMPARED TO THE
GFS AND ECMWF. THERE WILL ALSO BE THE POTENTIAL FOR A BAND OF LAKE
ENHANCED SNOW OFF OF LAKE MI THAT COULD SPREAD EASTWARD FROM NEAR
THE GARDEN PENINSULA INTO LUCE COUNTY. SINCE THE STRONGEST LOW
LEVEL CONV IS EXPECTED TO MOVE STEADILY TO THE EAST...SNOW AMOUNTS
IN ANY ONE LOCATION SHOULD BE LIMITED. HOWEVER...CONFIDENCE IS LOWER
FOR THE POSITION/STRENGTH OF THIS FEATURE THAT COULD ADD SEVERAL
INCHES TO THE SNOW TOTALS.
FRI NIGHT INTO SAT...SFC LOW PRES IS FCST TO SPREAD FROM THE NRN
PLAINS TO THE UPPER MS VALLEY WITH CONTINUED WAA BRINGING
SUBSTANTIAL 850 MB WARMING. NAM/GFS 285-295K ISENTROPIC PROGS
SUGGEST THAT THE STRONGEST LIFT AND DEEPEST MOISTURE WILL REMAIN
ACROSS LAKE SUPERIOR AND FAR NRN UPPER MI. WITH A PROMINENT 850-700
MB DRY LAYER DEVELOPING TO THE SOUTH...FREEZING DRIZZLE WILL BE
POSSIBLE ALONG WITH SOME LIGHT SNOW OR FLURRIES AS ICE NUCLEI BECOME
MORE SCARCE. ANY PCPN AMOUNTS ARE EXPECTED TO BE LIGHT WITH
ONLY A FEW HUNDREDTHS OF AN INCH AT MOST. THERE MAY ALSO BE ENOUGH
900-700 MB WARMING INTO THE AREA OF DEEPER MOISTURE FOR SOME
FZRA.
SAT NIGHT AND SUN...LOW PRES LIFTING NE TOWARD JAMES BAY SAT NIGHT
WILL DRAG A COLD FRONT THROUGH THE NRN LAKES WITH MUCH COLDER AIR
MOVING IN ON NW WINDS. WITH 850 MB TEMPS FALLING TO NEAR -18C...LES
WILL BE LIKELY FOR NW WIND SNOW BELTS. A LIMITING FACTOR FOR HEAVIER
SNOW WILL BE SUBSTANTIAL 850-700 MB DRYING WITH BACKING AND
INCREASING ACYC LOW LEVEL WINDS FROM LATE SUN INTO SUN NIGHT.
MON-WED...THE GFS/GEFS AND ECMWF WERE IN REASONABLE AGREEMENT WITH
THE PATTERN INTO NEXT WEEK WITH HIGH PRES BUILDING INTO THE REGION
MON INTO MON NIGHT BRINGING DIMINISHING LES. ANOTHER MID LEVEL AND
SFC TROUGH MOVING THROUGH TUE INTO TUE NIGHT COULD BRING SOME LIGHT
SNOW TO THE AREA. THE MODELS HAVE TRENDED TOWARD KEEPING COLDER
ACROSS REGION THAT WOULD KEEP ANY PCPN AS SNOW WITH MAX TEMPS
RECOVERING INTO THE MID 20S TO AROUND 30 BY TUE AND WED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 126 AM EST THU NOV 27 2014
WITH INCREASING SUBSIDENCE/DRY ADVECTION IN ADVANCE OF HI PRES
MOVING E FM THE NRN PLAINS...EXPECT GRADUALLY IMPROVING CONDITIONS
AT THE TAF SITES FM IFR IN THE FIRST COUPLE HRS TO PREDOMINANT MVFR.
WITH THE MOST FAVORABLE UPSLOPE/CONFLUENT N WIND...IWD WL SEE A
LONGER PERSISTENCE OF SHSN/IFR VSBYS. AS THE HI AND ACCOMPANYING
DRIER AIR EDGE CLOSER ON THANKSGIVING...THE LLVL WINDS WL BACK
TOWARD THE W BY LATE THIS AFTN AND THEN TO THE WSW THIS EVNG...
RESULTING IN A RETURN TO VFR CONDITIONS IN THE AFTN AT IWD AND SAW.
BUT MORE UPSLOPE WIND AT CMX MAY HOLD CIGS IN THE MVFR RANGE AT THAT
LOCATION THRU THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 PM EST WED NOV 26 2014
A SFC TROUGH WILL SLIDE SOUTH OVER LAKE SUPERIOR TONIGHT.
BEHIND THE TROUGH...EXPECT NORTHERLY WINDS TO 30 KTS. WINDS WILL
THEN DIMINISH TO UNDER 20 KT W TO E THU/THU NIGHT AS HIGH PRES RIDGE
ARRIVES. WITH ANOTHER COLD FRONT PUSHING ACROSS THE UPPER LAKES SAT
NIGHT...EXPECT INCREASING S/SW WINDS TO 15-25KT FRI INTO SAT AHEAD
OF FRONT. BEHIND THE FRONT...NW WINDS MAY REACH 20-30KT LATE SAT
NIGHT AND SUN AND INCREASE TO GALES BY SUN NIGHT INTO MON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR MIZ001-
003-004.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MIZ005.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR MIZ002-009.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
356 AM CST Thu Nov 27 2014
.SHORT TERM: (Today through Saturday)
Issued at 356 AM CST Thu Nov 27 2014
Clipper system is now well southeast of the CWFA, and only a few
lingering flurries remain. Expect any lingering precip to end by
12Z this morning and for the rest of the day to be cold and dry.
Some uncertainty on sky condition today as stratus over Iowa is
clearing fairly slowly from northwest to southeast. Short range NAM
and RAP 925mb RH field has a decent handle on the clouds at this
time, so have used a combination of these guidance products and
satellite observations to try and time gradual clearing today.
Canadian airmass over eastern Dakotas at this time will drift
southeast today and will provide the area with unseasonably cold
air. Cannot argue with MOS high temps in the mid-upper 20s to mid
30s across the area due to this cold high pressure system`s
influence.
Models continue to advertise a general pattern shift Friday into the
weekend with mid-upper level flow becoming more zonal. This will
allow warmer air to flow back into the area as the storm track
shifts north. Temperatures will moderate on Friday as the flow
shifts to the south-southwest on the western side of the Canadian
high which will have settled in over the Eastern CONUS. Expect
temperatures on Friday to be at least 10 to 15 degrees warmer than
today. Boundary layer moisture will also be on the increase, and
low level RH progs for Friday night/Saturday morning are showing
very moist conditions across the area by 12Z Saturday from about
900mb down to the surface. Have therefore increased cloud cover on
Saturday morning with some gradual clearing during the afternoon.
Models continue to spit out light QPF Saturday, but am still
skeptical due to the models` tendency to develop precipitation in
strong moisture return situations even with lifting mechanisms
aren`t present. Indeed, in this case model soundings are showing a
strong subsidence inversion in the low levels and positive values of
omega in the moist layer which would tend to lend credence to a dry
(tho cloudy/mostly cloudy) forecast for Saturday. Am still sticking
with above normal temperatures Saturday, though due to expected
cloud cover have backed off a little bit from warmest MOS guidance.
Carney
.LONG TERM: (Thursday through Next Wednesday)
Issued at 351 PM CST Wed Nov 26 2014
Ridge of high pressure to move into the region on Thanksgiving with
colder temperatures. Clouds will be slow to clear out so temps to
only rise into the mid 20s to around 40.
Another cold night Thursday night with lows in the 20s. Then surface
ridge moves to the east allowing southerly winds to return and
become gusty on Friday. So highs will be near normal in the mid 40s
to mid 50s.
Warmer weather to persist through the weekend with highs in the mid
50s to mid 60s on Saturday and lows Saturday night in the low 40s to
low 50s. Models still bring a cold front into region during the day
on Sunday. High temp forecast to be tricky depending on timing of
this frontal boundary. For now have highs in the upper 40s far north
to the mid 60s far south. Otherwise, low level moisture will be on
the increase ahead of this front so could see some rain across
southern half of forecast area Sunday through Monday with it mixing
with or changing over to snow at times. Lows Sunday night will be in
the upper teens to mid 30s. Highs on Monday will be in the low 30s
to low 40s.
Weak surface ridge to build in Monday night and Tuesday. So will see
dry conditions with lows Monday night in the low 20s to low 30s and
highs on Tuesday in the 40s.
Beyond that extended models have differing solutions with ECMWF a
bit faster with next frontal passage and drier vs. GFS which is
slower and much wetter solution. For now went with a blend, have
slight chance pops Tuesday night and chance pops on Wednesday.
Temperatures to be near freezing Tuesday night in northern portions
of forecast area so could see a mix of rain and snow. Otherwise,
rain possible for mid week next week.
Byrd
&&
.AVIATION: (For the 06z TAFs through 06z Thursday Night)
Issued at 1134 PM CST Wed Nov 26 2014
IFR flight conditions were widespread earlier this evening across
eastern MO and western IL into southeast IA. However over the last
few hours there has been a dramatic improvement as the surface low
redevelops in the TN valley, winds shift to north and northwesterly,
and snowfall diminishes. Radar and present trends suggest snow
should end across the St. Metro area within the next hour or two
with conditions improving at that time to MVFR. Elsewhere MVFR
conditions will persist overnight. During the day on Thursday the
cig heights are expected to gradually improve with VFR flight
conditions evolving from midday into the afternoon.
Specifics for KSTL:
Snow is expected to end by 07z with flight conditions improving at
that time to MVFR. MVFR flight conditions will then persist
through early afternoon with cig heights gradually rising, with
VFR conditions around 21z.
Glass
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 32 26 50 39 / 0 0 0 0
Quincy 24 20 45 36 / 0 0 0 0
Columbia 32 25 54 40 / 0 0 0 0
Jefferson City 33 26 56 41 / 0 0 0 0
Salem 30 23 45 37 / 5 0 0 5
Farmington 35 24 49 39 / 0 0 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1148 PM CST WED NOV 26 2014
.SYNOPSIS...
ISSUED AT 318 PM CST WED NOV 26 2014
H5 ANALYSIS FROM THIS MORNING HAS A CLOSED LOW OVER
NUNAVUT WITH A TROUGH EXTENDING SWD INTO THE SERN CONUS. A COUPLE OF
UPPER LEVEL DISTURBANCES WERE NOTED OVER KENTUCKY AND NRN MO. STRONG
WINDS WERE NOTED IN THE MID LEVELS AS A 90+KT H5 JET STREAK EXTENDED
FROM WESTERN MT INTO SWRN KS. AT THE SURFACE...LOW PRESSURE WAS
PRESENT OVER NRN MO WITH A COLD FRONT EXTENDING SOUTH AND WEST OF
THE LOW INTO THE OZARKS AND TX PANHANDLE. COLD AIR BEHIND THE FRONT
HAS BACKED TO ALONG THE FRONT RANGES OF THE ROCKIES IN COLORADO AND
WYOMING. LOOKING AT THE H7 THERMAL FIELD...A DECENT FRONTAL BOUNDARY
EXTENDED ACROSS THE PANHANDLE AND EXTREME SOUTHWESTERN NEBRASKA. THE
H7 FRONT...COUPLED WITH THE H5 JET STREAK...HAS LED TO LIGHT SNOW
ACROSS THE PANHANDLE AND NORTHEASTERN COLORADO THIS AFTERNOON. SKIES
WERE MOSTLY CLOUDY ACROSS WESTERN AND NORTH CENTRAL NEBRASKA THIS
AFTERNOON. TEMPERATURES AS OF MID AFTERNOON RANGED FROM 25 AT ONEILL
TO 34 AT NORTH PLATTE AND OGALLALA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 318 PM CST WED NOV 26 2014
LOW TO MID LEVEL FRONTOGENETIC BAND CURRENTLY
ACROSS SOUTHWEST NEBRASKA IS SHOWN BY THE HIRES NEAR TERM MODELS TO
BECOME LESS DEFINED THROUGH THE AFTERNOON AS THE ATMOSPHERE LOSES
SATURATION IN THE DENDRITIC GROWTH ZONE. THE HRRR SEEMS TO BE
HANDLING THE CURRENT SITUATION WELL...THUS THE FORECAST WAS TRENDED
IN THAT DIRECTION WITH SNOW ENDING ACROSS OUR SOUTHWEST THIS
EVENING. THE LATEST HRRR DOES SHOW ANOTHER PUSH OF LOWER LEVEL
MOISTURE THIS EVENING...THUS THE REASON OF EXTENDING A SNOW MENTION
INTO THIS EVENING. ACROSS NORTH CENTRAL NEBRASKA THIS
EVENING...BUFR SOUNDINGS SHOW DEEP SATURATION...WHICH AT TIMES
REACHES INTO THE DGZ...WHATS MISSING IS DEEP LIFT...BUT THERE ARE
INDICATIONS OF AT LEAST WEAK OMEGA. PREVIOUS FORECAST HANDLED THIS
POTENTIAL WITH --SN...WILL DO THE SAME.
OVERNIGHT LOWS WILL BE CHILLY...WITH LESS MIXING IN MIND OVERNIGHT
LOWS SHOULD BOTTOM OUT IN THE TEENS ACROSS THE EAST...WITH LOWER 20S
OVER THE HIGHER TERRAIN OF THE WEST.
TOMORROW...A GENERAL WARMING AND DRYING TREND IS FORECAST BY ALL
AVAILABLE GUIDANCE AS SFC HIGH PRESSURE BUILDS OFF TO THE EAST AND A
LEE TROUGH DEEPENS TO THE WEST. SOUTHERLY...TO WESTERLY FLOW WILL
ADVECT WARMER H85 TEMPS ACROSS THE REGION...WITH OUR FAR WESTERN &
SOUTHWESTERN ZONES TOPPING 10C BY 00Z FRIDAY. THIS SHOULD PROVIDE
FOR TEMPERATURES IN THE LOWER 60S ACROSS SOUTHWEST NEBRASKA AND THE
EASTERN PANHANDLE. THERE WILL REMAIN A SHARP GRADIENT OF
TEMPERATURES AS ONE HEADS EAST. ACROSS THE HEART OF THE SANDHILLS
HIGHS IN THE 40S AND 50S SHOULD PREVAIL...TO THE EAST OF
THERE...ACROSS NORTH CENTRAL NEBRASKA...HIGHS MAY STRUGGLE TO REACH
INTO THE MID 30S...OWING THE PRESENCE OF PERSISTENT STRATUS AND
COOLER AIR RECYCLED FROM THE DEPARTING HIGH. YOUR THANKSGIVING
FORECAST IS DRY AS THE TROPOSPHERIC COLUMN IS SHOWN TO DRY ON
THURSDAY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 318 PM CST WED NOV 26 2014
MID RANGE...THURSDAY NIGHT THROUGH SATURDAY...IN THE
MID RANGE...UNSEASONABLY WARM AND DRY CONDITIONS ARE
EXPECTED...WITH THE MAIN FORECAST CHALLENGE BEING HIGH TEMPERATURES
FOR FRIDAY AND SATURDAY. FOR THURSDAY NIGHT...A WARM FRONT WILL
CONTINUE TO LIFT NORTHEAST OF THE AREA INTO NORTH DAKOTA AND
MINNESOTA. A WEAK SURFACE TROUGH OF LOW PRESSURE WILL DEVELOP ACROSS
THE HIGH PLAINS OF NEBRASKA AND KANSAS OVERNIGHT LEADING TO LIGHT
WESTERLY WINDS. OVERNIGHT LOWS WILL BE ON THE MILD SIDE FOR THIS TIME OF
YEAR WITH READINGS AROUND 25 FORECAST FOR FRIDAY MORNING. WITH LIGHT
WESTERLY WINDS FORECAST...WENT WITH SOME LOWER 20S IN THE PLATTE
RIVER VALLEY. FRIDAY AND FRIDAY NIGHT...WARM H85 TEMPS WILL PUSH
INTO THE REGION WITH H85 TEMPS RANGING FROM 8 TO 16C. THIS WILL
RESULT IN HIGHS WELL INTO THE 50S TO MIDDLE 60S FRIDAY AFTERNOON. ON
FRIDAY NIGHT...LOWS WILL BE MILD WITH TEMPERATURES IN THE UPPER 20S
TO LOWER 30S EXPECTED. ON SATURDAY...AN ARCTIC COLD FRONT WILL PUSH
INTO THE DAKOTAS...ENDING UP SOMEWHERE IN SOUTH DAKOTA BY 00Z
SUNDAY. THE EURO SOLN IS MOST AGGRESSIVE WITH THE FRONT BEING ALONG
THE SD/NE BORDER BY THIS TIME. THE NAM AND GFS ARE SLOWER AND HAVE
THE FRONT OVER CENTRAL AND NORTHERN SD DURING 00Z SUNDAY.
REGARDLESS...THE FRONT WILL BE NORTH OF THE FORECAST AREA BEFORE
PEAK HEATING. WITH THE APPG FRONT AND H85 TEMPS REACHING THE MIDDLE
TO UPPER TEENS SAT AFTN...HIGHS WILL SURGE INTO THE 60S AND MAY
APPROACH 70 IN THE SOUTHWEST. RECORDS FOR SATURDAY ARE IN THE MID
70S FOR VALENTINE AND IMPERIAL...AND 71 FOR NORTH PLATTE AND 69 FOR
BROKEN BOW RESPECTIVELY.
LONG RANGE...SATURDAY NIGHT THROUGH WEDNESDAY...A STRONG ARCTIC
FROPA WILL PUSH THROUGH THE FORECAST AREA SATURDAY NIGHT. FORECAST
WILL CONTINUE TO BE DRY BEHIND THE FRONT WITH THE BEST FORCING OVER
NORTH DAKOTA AND NRN MINNESOTA. H85 TEMPS BEHIND THE FRONT SUNDAY
WILL RANGE FROM -13C IN THE NORTH TO -7C IN THE SOUTH. WITH DECENT
NORTHERLY WINDS AND MIXING HIGHS WILL STRUGGLE TO GET OUT OF THE 20S
SUNDAY. TEMPERATURES WILL MODERATE SOME MONDAY...WITH A BETTER
WARMUP EXPECTED ON TUESDAY AND WEDNESDAY. BY WEDNESDAY...THE
PRECIPITATION FORECAST BECOMES MORE OF A CHALLENGE THANKS TO SPLIT
FLOW. THE LATEST GFS AND ECMWF HAVE DIVERGENT SOLUTIONS TOWARD THE
MIDDLE OF THE WEEK. THE GFS IS MOST AGGRESSIVE...PUSHING A SHORTWAVE
TROUGH ACROSS THE INTERMOUNTAIN WEST WEDNESDAY...WHILE THE ECMWF HAS
THE TROUGH IN NRN CALIFORNIA. WITH THE MODEL DISAGREEMENTS
ATTM...WILL LEAVE THE PERIOD DRY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1145 PM CST WED NOV 26 2014
FLURRIES AND MARGINAL CEILINGS ARE EXPECTED TO CONTINUE THROUGH
THE NIGHT IN NORTHERN NEBRASKA. OTHERWISE...CEILINGS WILL BE WELL
INTO THE VISUAL RANGE TONIGHT AND WILL BECOME UNLIMITED LATE
THURSDAY MORNING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...JACOBS
LONG TERM...CLB
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1248 AM EST THU NOV 27 2014
.SYNOPSIS...
SNOW WILL DIMINISH TO AREAS OF LIGHT SNOW AND FLURRIES TONIGHT AS
THE STORM THAT BROUGHT HEAVY SNOW TO PARTS OF THE AREA EARLIER
TODAY MOVES NORTHEAST TOWARD THE CANADIAN MARITIMES. A SERIES OF
UPPER- LEVEL DISTURBANCES WILL BRING OCCASIONAL LIGHT SNOW SHOWERS
AND FLURRIES THURSDAY THROUGH SATURDAY...WITH TEMPERATURES STAYING
ON THE CHILLY SIDE.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPDATED AT 1015 PM... LOW PRESSURE WILL BE TRACKING EAST OF CAPE
COD OVERNIGHT AND THE BAND OF HEAVY SNOW THAT PERSISTED OVER
PORTIONS OF THE AREA EARLIER TODAY HAS NOW MOVED EAST OFF TO THE
EAST. AREAS OF LIGHT SNOW AND FLURRIES REMAIN IN THE WAKE OF THE
STORM OVERNIGHT AS LOTS OF LOW AND MID-LEVEL MOISTURE WILL
REMAIN IN PLACE. IN ADDITION SOME WEAK LIFT WILL BE GENERATED BY
THE PRESENCE OF WEAK SURFACE TROUGHING OVER NEW YORK STATE IN
THE LIGHT NNW FLOW REGIME. TEMPERATURES WILL BE MARGINALLY COLD
ENOUGH FOR SOME LAKE ENHANCEMENT BUT THE FLOW IS VERY LIGHT AND
EXPECT ADDITIONAL ACCUMULATIONS GENERALLY LESS THAN AN INCH. HAVE
CANCELLED THE WINTER WEATHER ADVISORIES FOR THE CENTRAL SOUTHERN
TIER AND EASTERN FINGER LAKES AS REPORTS ARE INDICATING THAT MAIN
ROADWAYS ARE MOSTLY JUST WET... ALTHOUGH FALLING TEMPERATURES
COULD STILL LEAD TO SOME ICY SPOTS IN THOSE AREAS... AND SOME
SECONDARY ROADS COULD STILL BE SNOW COVERED. FARTHER EAST WILL LET
THE WARNINGS CONTINUE FOR AWHILE AS ROADS WILL STILL BE HAZARDOUS
AND SNOW COVERED IN MANY AREAS DESPITE ONLY LIGHT SNOW EXPECTED
OVERNIGHT. PREVIOUS DISCUSSION IS BELOW.
UPDATED AT 615 PM... SURFACE LOW PRESSURE WELL EAST OF THE NJ
COAST CONTINUES TO TRACK NORTHEAST EARLY THIS EVENING WITH THE 700
MB BEGINNING TO CLOSE OFF OVER NORTHEAST PA AND SOUTHEAST NY.
PERSISTENT BAND OF MID-LEVEL FRONTOGENESIS CONTINUES TO BE THE
MAIN DRIVER OF A PERSISTENT SNOW BAND THAT HAS BEEN OVER OUR
CENTRAL COUNTIES FOR THE PAST SEVERAL HOURS. THIS FORCING WILL BE
MOVING OFF TO THE EAST DURING THE NEXT FEW HOURS.
THE PERSISTENT BAND OF HEAVY SNOW IS FINALLY BEGINNING TO MOVE
EAST NOW WITH SNOW BEGINNING TO DIMINISH TO THE WEST OF THE BAND.
SNOWFALL TOTALS WITHIN THIS BAND HAVE BEEN MOSTLY IN THE 7 TO 10
INCH RANGE FROM BRADFORD TO BROOME TO CHENANGO COUNTIES. WITH THIS
BAND NOW MOVING EAST EXPECT SNOW TO DIMINISH RAPIDLY IN INTENSITY
WEST OF I-81 AFTER 7 PM... AND OVER OUR EASTERN COUNTIES BY
MIDNIGHT. SNOWFALL WITHIN THE BAND IS STILL PRETTY INTENSE WITH
RATES OF 1 TO 2 INCHES PER HOUR. BASED ON THE EXPECTED EVOLUTION
OF THE STORM ANOTHER 2 TO 4 INCHES OF SNOW CAN BE EXPECTED EAST OF
I-81 THIS EVENING WITH LESS THAN 2 INCHES THE WEST. BASED ON THIS
OUR CURRENT WARNING CONFIGURATION LOOKS VERY GOOD... WITH WARNINGS
CONTINUING ALONG AND EAST OF A LINE FROM BRADFORD TO TIOGA TO BROOME
TO CHENANGO COUNTIES FOR UP TO 12 INCHES OF SNOW... AND A STRIPE
OF ADVISORIES FOR 3 TO 6 INCHES JUST TO THE WEST. HAVE MADE SOME
MINOR CHANGES TO SNOWFALL FORECASTS WITH THIS UPDATE... OTHERWISE
NO SIGNIFICANT CHANGES. PREVIOUS DISCUSSION IS BELOW.
4 PM UPDATE... BASED ON PERSISTENCE OF NARROW CSI BAND...AND THE
EXPECTATION OF ANOTHER 2-3 HRS OF +SN UNDERNEATH IT...WE`VE ADDED
BRADFORD PA AND TIOGA NY TO THE WRNG AREA (STORM TOTALS OF
5-10").
3 PM UPDATE... FOR THE MOST PART...ONGOING WINTER STORM IS
BEHAVING ITSELF...AS A DEEPENING SURFACE CYCLONE IS MOVING NEWD
OFF THE MID-ATLANTIC COAST.
OF PRIMARY CONCERN LATE THIS AFTN INTO THE EVE HRS IS THE TRACK
OF THE MID-LVL LOW (700 MB)...AND AN ASSOCD BAND OF FGEN
FORCING...FROM CNTRL/NERN PA INTO PTNS OF NY`S SRN TIER...THEN
NEWD FROM THERE. BASED ON THE LATEST OBSERVATIONAL DATA...SPC
MESO-ANALYSES...AND THE LATEST HI-RES MODEL OUTPUT...THE MAIN BAND
OF +SN MAY WELL IMPACT AN AXIS FROM NEAR WILLIAMSPORT...TO
TOWANDA...TO BINGHAMTON...TO NORWICH AND COOPERSTOWN THROUGH AT
LEAST 21-23Z...WITH A GENERAL EWD SHIFT THEREAFTER. ACRS OUR SERN
ZNS...PROXIMITY OF A MID-LVL DRY SLOT MAY CAUSE SNOW TO OCNLY
DECREASE...BUT IT`S NOT LIKELY TO SHUT DOWN ALTOGETHER UNTIL LTR
THIS EVE...SO ADDITIONAL ACCUMS ARE STILL ANTICIPATED EVEN IN
THESE AREAS. ALL IN ALL...CURRENTLY ADVERTISED SNOWFALL TOTALS
STILL LOOK REASONABLE...WITH A GENERAL 6-12" IN THE WRNG
AREA OVER MOST OF NERN PA...THE CATSKILLS...AND SXNS OF THE SUSQ RGN...AND
ROUGHLY 3-6" IN THE ADVISORY RGN...FROM KELM-KITH-KSYR.
BASED ON THE LATEST HRRR DATA...WHICH HAS PERFORMED WELL TDY...THE
BACK EDGE OF THE STEADIER SNOW PULLS OUT FROM W TO E AFTER 01-03Z.
ALTHOUGH WE COULD SEE SOME WEAK MULTI-BANDS TWDS DAYBREAK IN A
310-330 FLOW...THE OVERALL FLOW LOOKS WEAK...AND MOISTURE DEPTHS
WILL BE ON THE DECLINE...SO ACCUMS SHOULD BE VERY MINOR.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
FOR THANKSGIVING DAY AND THU NGT...A NW FLOW PATN WILL
PREVAIL...WITH LOW-LVL CAA...AND LINGERING BLYR MOISTURE. FOR THE
MOST PART...THIS WILL PRODUCE -SHSN AND FLRYS...AND SMALL ACCUMS.
HOWEVER...A BRIEF PD OF ENHANCEMENT COULD OCCUR LTR THU NGT INTO
FRI MRNG...WHEN A WELL DEFINED NRN STREAM S/WV CROSSES NY/PA. SOME
SYNOPTIC SUPPORT FROM THE S/WV AND LK ENHANCEMENT COULD PRODUCE
LOCALLY 1-3" IN AN AXIS FROM SRN CAYUGA-ONONDAGA...TO SRN
ONEIDA/MADISON/NRN CHENANGO/NRN OTSEGO.
FOR THE REST OF THE DAY FRI INTO FRI NGT...MAINLY JUST SCTD
-SHSN/FLRYS ARE AGN ANTICIPATED...WITH BACKING LOW-LVL FLOW...AS
SOME WARM ADVECTION BEGINS.
ANOTHER S/WV PASSAGE...ALG WITH THE APPROACH OF THE SFC-850 MB
WARM FRNT FROM THE SW...COULD LEAD TO ADDNL -SHSN AND SOME LGT
ACCUMS AS WE HEAD INTO EARLY SAT...SPCLY FOR OUR NRN ZNS.
DAILY HIGHS WILL GENERALLY BE IN THE 30S...WITH LOWS IN THE UPR
TEENS AND 20S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
230 PM EST UPDATE...
FOLLOWED CLOSELY WITH WPC GUIDANCE AND MADE MINOR CHANGES TO THE
PREVIOUS FORECAST.
THE MAIN THEME OF THE FORECAST CONTINUES WITH ZONAL FLOW STILL
BEING EXPECTED ACROSS MUCH OF THE NORTHEAST THROUGH THE FORECAST
PERIOD.
BY SAT NIGHT A WARM FRONT WILL HAVE JUST PASSED TO THE NORTH OF
THE CWA AND A COLD FRONT WILL BE STARTING TO APPROACH THE REGION
FROM THE WEST. THIS COLD FRONT WILL BRING COOLER AIR TO THE REGION
ALONG WITH A CHANCE FOR RAIN/AND OR SNOW SHOWERS TO NEW YORK AND
PENNSYLVANIA. A SFC RIDGE WILL THEN START TO BUILD OVER THE AREA
FROM THE WEST MONDAY AFTERNOON... THUS BRINGING DRY AND QUIET
WEATHER BACK TO THE AREA THROUGH MID WEEK. THIS RIDGE WILL ALSO ALLOW
TEMPERATURES OVER THE REGION TO FALL BELOW THE SEASONAL NORM. THE
COLDEST DAY IN THE EXTENDED FORECAST WILL BE WHEN THE RIDGE IS EXPECTED
TO BE CENTERED OVER THE CWA. THIS WILL OCCUR ON TUESDAY. HIGH
TEMPERATURES ARE EXPECTED TO RISE INTO THE LOW TO MID 30S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
06Z UPDATE...
SNOW IS WINDING DOWN ACROSS TERMINALS AT THIS TIME THOUGH
POTENTIAL EXISTS FOR IFR VSBYS/CIGS FOR FIRST SEVERAL HOURS OF TAF
VALID TIME. RME AND SYR MAY SEE 2SM IN LIGHT SNOW THROUGH 08Z WITH
ITH SEEING IFR CIGS THROUGH 12Z. PREDOMINANT MVFR -SHSN EXPECTED
AT NY TERMINALS THIS MORNING.
UNRESTRICTED SNOW SHOWERS THEN EXPECTED DURING THE AFTERNOON HOURS
IN WRAP-AROUND MOISTURE WITH MVFR CIGS LINGERING WITH EXCEPTION OF
AVP AND ELM AFTER 17Z AND BGM AFTER 21Z.
WINDS OUT OF THE NW AROUND 5KTS TONIGHT WILL BACK TO THE WEST
AFTER 00Z FRIDAY.
OUTLOOK...
THU NGT/FRI/SAT...POSSIBLE RESTRICTIONS FROM SCT -SHSN...ESPECIALLY
KSYR-KRME.
SUN...RESTRICTIONS POSSIBLE FROM -SHRA.
MON...RESTRICTIONS POSSIBLE FROM -SHRA/SHSN.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
PAZ038>040-043-044-047-048-072.
NY...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
NYZ045-046-055>057-062.
&&
$$
SYNOPSIS...MLJ
NEAR TERM...MLJ/MSE
SHORT TERM...MLJ
LONG TERM...KAH
AVIATION...PVF
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1144 PM CST WED NOV 26 2014
.UPDATE...
ISSUED AT 1143 PM CST WED NOV 26 2014
TEMPS CONTINUE TO FALL IN FAVORED AREAS...FSE AND NEW SNOWFALL AREAS
IN THE SOUTHWEST ZONES. LOW TEMPS TWEAKED DOWN A BIT. TOOK CLOUDS
OUT OF THE SOUTHERN ZONES FOR THE NIGHT. NO OTHER CHANGES MADE.
UPDATE ISSUED AT 1006 PM CST WED NOV 26 2014
HIGH PRESSURE WAS LOCATED DOWN THE RED RIVER. WILL LOWER TEMPS WITH
FRESH SNOW COVER OVER SOUTHWEST COUNTIES. DEWPOINTS CONTINUE TO FALL
WITH FALLING TEMPS. WILL LOWER TEMPS FOR TONIGHT MOST AREAS. NO
OTHER CHANGES MADE.
UPDATE ISSUED AT 656 PM CST WED NOV 26 2014
NW TO SE ORIENTATED UPPER LEVEL JET WAS WEST OF THE FORECAST AREA
AND WILL SHIFT OVER THE RED RIVER VALLEY BY MORNING. PRECIPITABLE
WATER WAS UNDER ONE TENTH OF AN INCH AND WILL INCREASE SLIGHTLY IN
THE WESTERN ZONES BY MORNING. HIGH PRESSURE WAS LOCATED JUST WEST
OF THE RED RIVER. TEMPS ALREADY BELOW ZERO OVER ALL BUT THE FAR
SOUTHEAST ZONES. TWEAKED WINDS A BIT FOR TONIGHT. NO OTHER CHANGES
MADE AT THIS TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 328 PM CST WED NOV 26 2014
FORECAST CHALLENGE FOR THE SHORT TERM WILL BE OVERNIGHT LOWS
TONIGHT AS WELL AS TIMING AND AMOUNT OF SNOW THANKSGIVING NIGHT. A
SURFACE HIGH WILL DROP INTO THE VALLEY TONIGHT AND BRING A VERY
COLD AND DRY AIR MASS. THIS WILL RESULT IN OVERNIGHT LOWS WELL
BELOW SEASONAL NORMS. A CLIPPER THEN MOVES INTO EASTERN MONTANA
TOMORROW NIGHT AND A BAND OF SNOW IS EXPECTED TO FORM OVER
PORTIONS OF CENTRAL AND EASTERN NORTH DAKOTA ON INTO NORTHWEST
MINNESOTA. HAVE USED A BLEND OF NAM DNG AND HRRR FOR OVERNIGHT
LOWS TONIGHT AND A MODEL BLEND FOR THE THANKSGIVING NIGHT SYSTEM
AS THERE ARE STILL VARIATIONS ON THE PLACEMENT OF SNOW.
TONIGHT...CURRENT VIS SATELLITE SHOWS CLEARING LINE HAS MADE IT AS
FAR SOUTH OF I 94. DEW POINTS NORTH OF THIS MID CLOUD DECK ARE
ALREADY 5 TO 10 BELOW AND IN THE MID TEENS BELOW ACROSS SOUTHERN
MANITOBA. THE RIDGE AXIS EXTENDING OUT OF A HIGH OVER MANITOBA WILL
BRING CALM WINDS TO THE DVL REGION EARLY IN THE EVENING...AND WITH
A LIGHT COVERING OF FRESH SNOW THE TEMPS SHOULD QUICKLY DROP TO 5
TO 10 BELOW THIS EVENING. BY MORNING...RETURN FLOW SETS UP OVER
THE DEVILS LAKE BASIN REGION UP THROUGH
TOWNER/PEMBINA/CAVALIER COUNTIES. THIS WILL ALLOW WIND CHILLS TO
DROP INTO THE 20 TO 25 BELOW RANGE TONIGHT...AND EVENING SHIFT
WILL NEED TO MONITOR CLOSELY AS COLDER TEMPS WOULD BRING AREA INTO
WIND CHILL ADVISORY CRITERIA (LESS THAN 25 BELOW ZERO). WARMEST
TEMPS SHOULD BE ACROSS THE FAR SOUTH AS THE CURRENT MID CLOUDS
WILL DELAY RADIATIONAL COOLING FOR AT LEAST A FEW HOURS THIS
EVENING...BUT EXPECT THAT AREA TO CLEAR OUT BY 02Z TO 03Z. DEW
POINTS ARE ABOUT 10 DEG HIGHER IN THIS REGION SO NOT LOOKING FOR
AS SIGNIFICANT OF A DROP OFF. RIDGE AXIS SHOULD THEN BE OVER THE
EAST TOMORROW MORNING AND TEMPS SHOULD DROP TO AROUND 10 BELOW.
TOMORROW AND TOMORROW NIGHT...A VERY COLD START TO THE DAY WILL LIMIT
DAYTIME HIGHS DESPITE SOME SOLAR IN THE MORNING BEFORE WE SEE
INCREASING CLOUDS FROM WEST TO EAST TOMORROW AFTERNOON. TEMPS WILL
STRUGGLE TO BREAK 10 ABOVE. BAND OF SNOW ASSOCIATED WITH WARM
ADVECTION AND ISENTROPIC LIFT WILL SET UP OVER WESTERN ND TOMORROW
MORNING AND MOVE INTO CNTRL ND IN THE AFTN. A BAND OF ISENTROPIC
LIFT INTENSIFIES AND MOVES INTO THE WESTERN CWA BETWEEN 00Z AND
06Z. NAM 280K ISENTROPIC SFC WINDS IN THE 20 TO 30 KT RANGE ARE
DIRECTLY PERPENDICULAR TO THE PRESSURE GRADIENT AND SHOULD BE
SUFFICIENT TO LIFT THE PARCEL ABOUT 100 MB...WITH NEARLY SATURATED
CONDENSATION PRESSURE DEFICITS IN EASTERN NORTH DAKOTA. THERE IS
STILL DIFFERENCES IN THE PLACEMENT OF THE SNOW...WITH ECMWF A BIT
FURTHER SOUTH AND WEST THAN THE 18Z NAM AND 12Z GFS. HPC QPF
GUIDANCE PREFERS THE SLIGHTLY NORTHWARD SOLUTION...AND HAVE
UPDATED SNOW RATIOS TO YIELD 3 TO 4 INCHES IN NORTH OF THE DEVILS
LAKE REGION DOWN THROUGH THE CENTRAL VALLEY.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 328 PM CST WED NOV 26 2014
FRIDAY...SNOW SHOULD BEGIN TAPERING OFF FRIDAY MORNING BUT
PORTIONS OF EASTERN NORTH DAKOTA TO INCLUDE THE NORTHERN VALLEY
WILL HAVE ANOTHER TWO TO FOUR INCHES OF SNOW. MOTORISTS IN
NORTHEASTERN NORTH DAKOTA CAN EXPECT LESS THAN DESIRABLE DRIVING
CONDITIONS FOR BLACK FRIDAY SHOPPING...ESPECIALLY IN THE EARLY
MORNING HOURS. ANOTHER SFC LOW ENTERS EASTERN MT FRI AFTN AND
MOVES INTO THE DAKOTAS OVERNIGHT. MODELS CONTINUING TO DIFFER ON
QPF AMOUNTS AND PLACEMENT OF THIS SECOND SHOT OF SNOW. GFS IS THE
MOST BULLISH AND BRINGS SOUTHERN EDGE OF SNOW BAND DOWN TO THE
HIGHWAY 2 CORRIDOR WHILE THE NAME IS FAIRLY DRY AND THE ECMWF
KEEPS SNOW MAINLY NORTH OF INTL BORDER. DO TO MODEL INCONSISTENCY
WILL USE CONTINUITY AS SOLUTION...WITH LOW CHANCE POPS ACROSS THE
NORTHERN TIER OF COUNTIES. WILL LIKELY SEE A BREAK MID DAY BETWEEN
THE TWO SNOW PRODUCING SYSTEMS SHOULD THE SNOW SET UP ALONG AND
NORTH OF HWY 200...THE MOST LIKELY AREA FOR ADDITIONAL
ACCUMULATION. DAYTIME HIGHS WILL BE WARMER ON FRIDAY AND JUMP
INTO THE MID 20S ACROSS THE SOUTH.
SATURDAY...GFS/ECMWF CONTINUE TO SHOW LINGERING SNOW SHOWERS
ACROSS THE NORTH AS NW SFC FLOW SETS UP...WHILE THE NAM REMAINS
DRY. WILL KEEP CONTINUITY FOR THIS PERIOD AS WELL...ALTHOUGH ANY
SNOW ON SATURDAY SHOULD BE LIGHT WITH LITTLE ACCUMULATION.
SATURDAY NIGHT THROUGH WEDNESDAY...MODELS START OUT IN FAIRLY DECENT
AGREEMENT...PUSHING A POSITIVELY TILTED TROUGH THROUGH THE NORTHERN
ROCKIES AND PLAINS OVER THE WEEKEND. THE COLD FRONT WILL MOVE
THROUGH THE CWA SATURDAY NIGHT AND COLD HIGH PRESSURE WILL BE IN
PLACE FOR SUNDAY. CONTINUED TO KEEP SOME 30ISH POPS FOR WHEN THE
FRONTAL BOUNDARY PASSES...THEN DRYING OUT INTO THE EARLY PART OF THE
WORK WEEK. TEMPS WILL AGAIN BE WELL BELOW AVERAGE WITH LOWS IN THE
TEENS BELOW ZERO AND HIGHS IN THE SINGLE DIGITS ABOVE FOR SUNDAY AND
MONDAY.
MODEL CONSENSUS STARTS TO DIVERGE BY TUESDAY AND WEDNESDAY. THE GFS
IS MORE ACTIVE AND BRING A VIGOROUS SHORTWAVE THROUGH THE NORTHERN
PLAINS WITH SFC LOW PRESSURE JUST TO OUR NORTH AND THE CWA SHOWING
SOME STRONG WARM AIR ADVECTION MONDAY AND EARLY TUESDAY BEFORE THE
NEXT COLD FRONT COMES IN. THE ECMWF IS WEAKER AND DRIER. ENSEMBLE
MEMBERS SHOW A GOOD AMOUNT OF SPREAD...SO FOR NOW KEPT ONLY MINIMAL
POPS AS THE OPERATIONAL GFS IS ONE OF THE WETTER SOLUTIONS. TEMPS
SHOULD SEE SOME WARMING ON TUESDAY AND COLDER AGAIN ON
WEDNESDAY...BUT EVEN THE HIGHER TEMP DAYS WILL STILL BE BELOW
SEASONAL AVERAGES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1143 PM CST WED NOV 26 2014
A CLEAR SKY WAS ACROSS THE FORECAST AREA. VFR CONDITIONS ARE EXPECTED
TONIGHT AND MUCH OF THU. MVFR CONDITIONS SHOULD BEGIN TO MOVE INTO
THE WESTERN ZONES ROUGHLY AFTER SUNSET AS CIGS LOWER.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...HOPPES
SHORT TERM...SPEICHER
LONG TERM...JR/SPEICHER
AVIATION...HOPPES
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1007 PM CST WED NOV 26 2014
.UPDATE...
ISSUED AT 1006 PM CST WED NOV 26 2014
HIGH PRESSURE WAS LOCATED DOWN THE RED RIVER. WILL LOWER TEMPS WITH
FRESH SNOW COVER OVER SOUTHWEST COUNTIES. DEWPOINTS CONTINUE TO FALL
WITH FALLING TEMPS. WILL LOWER TEMPS FOR TONIGHT MOST AREAS. NO
OTHER CHANGES MADE.
UPDATE ISSUED AT 656 PM CST WED NOV 26 2014
NW TO SE ORIENTATED UPPER LEVEL JET WAS WEST OF THE FORECAST AREA
AND WILL SHIFT OVER THE RED RIVER VALLEY BY MORNING. PRECIPITABLE
WATER WAS UNDER ONE TENTH OF AN INCH AND WILL INCREASE SLIGHTLY IN
THE WESTERN ZONES BY MORNING. HIGH PRESSURE WAS LOCATED JUST WEST
OF THE RED RIVER. TEMPS ALREADY BELOW ZERO OVER ALL BUT THE FAR
SOUTHEAST ZONES. TWEAKED WINDS A BIT FOR TONIGHT. NO OTHER CHANGES
MADE AT THIS TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 328 PM CST WED NOV 26 2014
FORECAST CHALLENGE FOR THE SHORT TERM WILL BE OVERNIGHT LOWS
TONIGHT AS WELL AS TIMING AND AMOUNT OF SNOW THANKSGIVING NIGHT. A
SURFACE HIGH WILL DROP INTO THE VALLEY TONIGHT AND BRING A VERY
COLD AND DRY AIR MASS. THIS WILL RESULT IN OVERNIGHT LOWS WELL
BELOW SEASONAL NORMS. A CLIPPER THEN MOVES INTO EASTERN MONTANA
TOMORROW NIGHT AND A BAND OF SNOW IS EXPECTED TO FORM OVER
PORTIONS OF CENTRAL AND EASTERN NORTH DAKOTA ON INTO NORTHWEST
MINNESOTA. HAVE USED A BLEND OF NAM DNG AND HRRR FOR OVERNIGHT
LOWS TONIGHT AND A MODEL BLEND FOR THE THANKSGIVING NIGHT SYSTEM
AS THERE ARE STILL VARIATIONS ON THE PLACEMENT OF SNOW.
TONIGHT...CURRENT VIS SATELLITE SHOWS CLEARING LINE HAS MADE IT AS
FAR SOUTH OF I 94. DEW POINTS NORTH OF THIS MID CLOUD DECK ARE
ALREADY 5 TO 10 BELOW AND IN THE MID TEENS BELOW ACROSS SOUTHERN
MANITOBA. THE RIDGE AXIS EXTENDING OUT OF A HIGH OVER MANITOBA WILL
BRING CALM WINDS TO THE DVL REGION EARLY IN THE EVENING...AND WITH
A LIGHT COVERING OF FRESH SNOW THE TEMPS SHOULD QUICKLY DROP TO 5
TO 10 BELOW THIS EVENING. BY MORNING...RETURN FLOW SETS UP OVER
THE DEVILS LAKE BASIN REGION UP THROUGH
TOWNER/PEMBINA/CAVALIER COUNTIES. THIS WILL ALLOW WIND CHILLS TO
DROP INTO THE 20 TO 25 BELOW RANGE TONIGHT...AND EVENING SHIFT
WILL NEED TO MONITOR CLOSELY AS COLDER TEMPS WOULD BRING AREA INTO
WIND CHILL ADVISORY CRITERIA (LESS THAN 25 BELOW ZERO). WARMEST
TEMPS SHOULD BE ACROSS THE FAR SOUTH AS THE CURRENT MID CLOUDS
WILL DELAY RADIATIONAL COOLING FOR AT LEAST A FEW HOURS THIS
EVENING...BUT EXPECT THAT AREA TO CLEAR OUT BY 02Z TO 03Z. DEW
POINTS ARE ABOUT 10 DEG HIGHER IN THIS REGION SO NOT LOOKING FOR
AS SIGNIFICANT OF A DROP OFF. RIDGE AXIS SHOULD THEN BE OVER THE
EAST TOMORROW MORNING AND TEMPS SHOULD DROP TO AROUND 10 BELOW.
TOMORROW AND TOMORROW NIGHT...A VERY COLD START TO THE DAY WILL LIMIT
DAYTIME HIGHS DESPITE SOME SOLAR IN THE MORNING BEFORE WE SEE
INCREASING CLOUDS FROM WEST TO EAST TOMORROW AFTERNOON. TEMPS WILL
STRUGGLE TO BREAK 10 ABOVE. BAND OF SNOW ASSOCIATED WITH WARM
ADVECTION AND ISENTROPIC LIFT WILL SET UP OVER WESTERN ND TOMORROW
MORNING AND MOVE INTO CNTRL ND IN THE AFTN. A BAND OF ISENTROPIC
LIFT INTENSIFIES AND MOVES INTO THE WESTERN CWA BETWEEN 00Z AND
06Z. NAM 280K ISENTROPIC SFC WINDS IN THE 20 TO 30 KT RANGE ARE
DIRECTLY PERPENDICULAR TO THE PRESSURE GRADIENT AND SHOULD BE
SUFFICIENT TO LIFT THE PARCEL ABOUT 100 MB...WITH NEARLY SATURATED
CONDENSATION PRESSURE DEFICITS IN EASTERN NORTH DAKOTA. THERE IS
STILL DIFFERENCES IN THE PLACEMENT OF THE SNOW...WITH ECMWF A BIT
FURTHER SOUTH AND WEST THAN THE 18Z NAM AND 12Z GFS. HPC QPF
GUIDANCE PREFERS THE SLIGHTLY NORTHWARD SOLUTION...AND HAVE
UPDATED SNOW RATIOS TO YIELD 3 TO 4 INCHES IN NORTH OF THE DEVILS
LAKE REGION DOWN THROUGH THE CENTRAL VALLEY.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 328 PM CST WED NOV 26 2014
FRIDAY...SNOW SHOULD BEGIN TAPERING OFF FRIDAY MORNING BUT
PORTIONS OF EASTERN NORTH DAKOTA TO INCLUDE THE NORTHERN VALLEY
WILL HAVE ANOTHER TWO TO FOUR INCHES OF SNOW. MOTORISTS IN
NORTHEASTERN NORTH DAKOTA CAN EXPECT LESS THAN DESIRABLE DRIVING
CONDITIONS FOR BLACK FRIDAY SHOPPING...ESPECIALLY IN THE EARLY
MORNING HOURS. ANOTHER SFC LOW ENTERS EASTERN MT FRI AFTN AND
MOVES INTO THE DAKOTAS OVERNIGHT. MODELS CONTINUING TO DIFFER ON
QPF AMOUNTS AND PLACEMENT OF THIS SECOND SHOT OF SNOW. GFS IS THE
MOST BULLISH AND BRINGS SOUTHERN EDGE OF SNOW BAND DOWN TO THE
HIGHWAY 2 CORRIDOR WHILE THE NAME IS FAIRLY DRY AND THE ECMWF
KEEPS SNOW MAINLY NORTH OF INTL BORDER. DO TO MODEL INCONSISTENCY
WILL USE CONTINUITY AS SOLUTION...WITH LOW CHANCE POPS ACROSS THE
NORTHERN TIER OF COUNTIES. WILL LIKELY SEE A BREAK MID DAY BETWEEN
THE TWO SNOW PRODUCING SYSTEMS SHOULD THE SNOW SET UP ALONG AND
NORTH OF HWY 200...THE MOST LIKELY AREA FOR ADDITIONAL
ACCUMULATION. DAYTIME HIGHS WILL BE WARMER ON FRIDAY AND JUMP
INTO THE MID 20S ACROSS THE SOUTH.
SATURDAY...GFS/ECMWF CONTINUE TO SHOW LINGERING SNOW SHOWERS
ACROSS THE NORTH AS NW SFC FLOW SETS UP...WHILE THE NAM REMAINS
DRY. WILL KEEP CONTINUITY FOR THIS PERIOD AS WELL...ALTHOUGH ANY
SNOW ON SATURDAY SHOULD BE LIGHT WITH LITTLE ACCUMULATION.
SATURDAY NIGHT THROUGH WEDNESDAY...MODELS START OUT IN FAIRLY DECENT
AGREEMENT...PUSHING A POSITIVELY TILTED TROUGH THROUGH THE NORTHERN
ROCKIES AND PLAINS OVER THE WEEKEND. THE COLD FRONT WILL MOVE
THROUGH THE CWA SATURDAY NIGHT AND COLD HIGH PRESSURE WILL BE IN
PLACE FOR SUNDAY. CONTINUED TO KEEP SOME 30ISH POPS FOR WHEN THE
FRONTAL BOUNDARY PASSES...THEN DRYING OUT INTO THE EARLY PART OF THE
WORK WEEK. TEMPS WILL AGAIN BE WELL BELOW AVERAGE WITH LOWS IN THE
TEENS BELOW ZERO AND HIGHS IN THE SINGLE DIGITS ABOVE FOR SUNDAY AND
MONDAY.
MODEL CONSENSUS STARTS TO DIVERGE BY TUESDAY AND WEDNESDAY. THE GFS
IS MORE ACTIVE AND BRING A VIGOROUS SHORTWAVE THROUGH THE NORTHERN
PLAINS WITH SFC LOW PRESSURE JUST TO OUR NORTH AND THE CWA SHOWING
SOME STRONG WARM AIR ADVECTION MONDAY AND EARLY TUESDAY BEFORE THE
NEXT COLD FRONT COMES IN. THE ECMWF IS WEAKER AND DRIER. ENSEMBLE
MEMBERS SHOW A GOOD AMOUNT OF SPREAD...SO FOR NOW KEPT ONLY MINIMAL
POPS AS THE OPERATIONAL GFS IS ONE OF THE WETTER SOLUTIONS. TEMPS
SHOULD SEE SOME WARMING ON TUESDAY AND COLDER AGAIN ON
WEDNESDAY...BUT EVEN THE HIGHER TEMP DAYS WILL STILL BE BELOW
SEASONAL AVERAGES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 656 PM CST WED NOV 26 2014
VFR CONDITIONS ARE ACROSS THE AREA AND EXPECT VFR CONDITIONS TONIGHT
AND THU. CIRRUS CLOUDS SHOULD MOVE IN AFTER MIDNIGHT AND CIGS SHOULD
LOWER TO AROUND 10 THOUSAND FT IN EASTERN ND...HIGHER IN THE EASTERN
ZONES THU AFTERNOON.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...HOPPES
SHORT TERM...SPEICHER
LONG TERM...JR/SPEICHER
AVIATION...HOPPES
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
345 AM EST THU NOV 27 2014
.SYNOPSIS...
WEAK CLIPPER EXITS SOUTHERN APPALACHIANS THIS MORNING. NORTHWEST FLOW
AND LINGERING MOISTURE PRODUCE UPSLOPE SNOW THROUGH TONIGHT. HIGH
PRESSURE FRIDAY AND SATURDAY. ANOTHER SYSTEM SUNDAY NIGHT AND MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WEAK CLIPPER SYSTEM EXITS EASTERN KY AND EASTERN TN THIS
MORNING. ON ITS WAY...LIGHT SNOW SHOWERS WILL BE POSSIBLE ACROSS
SOUTHWEST VA...AND EXTREME SOUTHERN WV DURING THE MORNING HOURS.
HOWEVER...WIND BECOMES NORTHWEST...AND WITH LINGERING
MOISTURE...UPSLOPE SNOW SHOWERS ARE LIKELY OVER THE CENTRAL AND
NORTHEAST MOUNTAINS THROUGH TONIGHT. KEPT CHANCE POPS OVER THE
WESTERN SLOPES AND EASTERN MOUNTAINS AND LIKELY POPS OVER
ELEVATIONS HIGHER THAN 3000 FEET.
MODELS INDICATE THAT BY 00Z FRIDAY...OUR AREA STILL UNDER THE BACK
EDGE OF THE H500 TROUGH...ACCOMPANY BY A STRONG ELONGATED
VORTICITY MAXIMA. H850 CHARTS SHOW EVEN COLDER AIR ADVECTING FROM THE
NORTHWEST BRINGING H850 TEMPERATURES AROUND MINUS 11C. THESE
CONDITIONS WILL COMBINE WITH THE UPSLOPE COMPONENT TO PRODUCE AN
INCH OR TWO AT HIGHER ELEVATIONS OF LIGHT SNOW LATE THURSDAY.
USED THE HRRR NUMBERS FOR HIGH TEMPERATURES TODAY...AND WENT
CLOSER TO THE COLDEST ADJECE NUMBERS FOR LOWS TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
WEAK SYSTEM PASSES BY TO THE NORTH ON SATURDAY. THEN A WEAK
BAROCLINIC ZONE DEVELOPS AND LINGERS OVER THE AREA FROM SATURDAY
THROUGH MONDAY WITH LOW POPS. FINALLY A MORE ORGANIZED SYSTEM
ROLLS THROUGH ON MONDAY...BUT MODELS VARYING WIDELY ON TIMING OF
THIS IMPULSE SO GENERALLY KEPT 30 TO 40 POPS OVER A LARGE PERIOD.
FRONT EXITS REGION ANYTIME BETWEEN MONDAY NIGHT TO TUESDAY
EVENING. NUDGED MORE TOWARDS SLOWER 00Z EURO. TOO WARM FOR SNOW
MOST PLACES DURING THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
GENERALLY USED THE ECMWF ENSEMBLE MEAN FOR THE FORECAST...WITH A BIT
OF THE GFS BLENDED IN. HIGH PRESSURE SLIDES EASTWARD SATURDAY NIGHT
AND SUNDAY...PROVIDING A SOUTHERLY FLOW. NEXT FRONTAL BOUNDARY
PUSHES INTO THE REGION SUNDAY NIGHT INTO MONDAY. HANDLING OF THIS
FRONT BEYOND MONDAY BECOMES A BIT MURKY. SOME MODELS DEVELOP A WAVE
ALONG THE FRONT FOR TUESDAY WHILE OTHERS PUSH THE FRONT TO THE SOUTH
AND DISSOLVE IT. WILL KEEP SOME SMALL POPS TUESDAY INTO WEDNESDAY
DUE TO THE UNCERTAINTY...BUT CONFIDENCE IS LOW.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
A VERY TRICKY FORECAST TONIGHT...AS LINGERING ABUNDANT MOISTURE
PRODUCING AREAS OF DENSE FOG...WHILE A MID CLOUD DECK SPREADS
ACROSS THE NORTHERN HALF OF WV...AND A CLIPPER LIKE SYSTEM PASSES
TO OUR SOUTH OVERNIGHT.
STARTING WITH LIFR VISIBILITIES AND CEILINGS AT PKB DUE TO DENSE
FOG. IFR CEILINGS EFFACING CRW AND IFR VISIBILITIES AFFECTING EKN.
CONDITIONS AT OTHER SITES REMAINS MVFR/VFR. HOWEVER...AS MID LEVEL
CLOUDS DRIFT NORTH NORTHEAST FROM THE SOUTH...CONDITIONS COULD
IMPROVE AT CRW. IN OTHER HAND...DOPPLER RADAR INDICATE RAIN SNOW
MIX SHOWERS OVER KY...MOVING NORTHEAST. SOME OF THESE SHOWERS
COULD REACH EXTREME SOUTHWEST OF VA AND PORTIONS OF SOUTHERN WV
OVERNIGHT...TO PRODUCE MVFR/IFR CONDITIONS THROUGH 12Z THURSDAY.
CONFIDENCE RUNNING LOW AT TM. PERIODS OF FLURRIES...DRIZZLE OR
FREEZING DRIZZLE COULD BE POSSIBLE MAINLY ACROSS THE SOUTHERN
THIRD AND CENTRAL MOUNTAINS THROUGH 12Z.
CLIPPER SYSTEM EXITS AFTER 12Z...WITH BOUNDARY LAYER WINDS
FINALLY INCREASING AND HELPING TO LIFT THE CEILINGS IN WV BETWEEN
15Z TO 18Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...
FORECAST CONFIDENCE: LOW.
ALTERNATE SCENARIOS: VSBY MAY BOUNCE UP AND DOWN DURING BREAKS IN
CLOUDS. VSBY OVER MOUNTAIN COUNTIES...INCLUDING BKW...MAY BE MORE
VARIABLE OVERNIGHT THAN INDICATED.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE THU 11/27/14
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EST 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14
CRW CONSISTENCY L L H H H H H H H H M M
HTS CONSISTENCY H H H H M H H H H M H H
BKW CONSISTENCY L H H M M H L M H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY L L M M H H M H H M H H
CKB CONSISTENCY H M M M M M H H H H H H
AFTER 06Z FRIDAY...
IFR CONDITIONS IN SNOW SHOWERS MAY LINGER OVERNIGHT THURSDAY NIGHT OVER
WV MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JW
NEAR TERM...ARJ
SHORT TERM...JW
LONG TERM...RPY
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS PORTLAND OR
901 PM PST WED NOV 26 2014
.SYNOPSIS...A WEAK COLD FRONT WILL PUSH SLOWLY INLAND TONIGHT AND
EARLY THU. THE FRONT WILL THEN STALL OVER WESTERN OREGON THU NIGHT
AND FRI...BEFORE ANOTHER STRONGER COLD FRONT WILL MOVE S THROUGH THE
REGION FRI NIGHT USHERING COLDER WEATHER FOR THE WEEKEND. HIGH PRES
OVER THE INTERIOR NW WILL TURN THE FLOW OFFSHORE BY SUN FOR DRY BUT
COLD WEATHER. SUN NIGHT AND MON A SYSTEM COMING UP FROM THE S WILL
ATTEMPT TO SPREAD SOME PRECIPITATION UP OVER THE COLD AIR MASS LEFT
OVER FROM THE WEEKEND.
&&
.UPDATE...NWS DOPPLER RADAR DEPICTS PRECIPITATION BEGINNING TO
SPREAD ONSHORE ACROSS THE REGION...THROUGH OBSERVATIONS
INDICATE THAT ACCUMULATIONS HAVE BEEN LIMITED THUS FAR...GENERALLY
ONLY A TRACE OR FEW HUNDREDTHS OF AN INCH AT BEST. FORECAST REMAINS
GENERALLY ON TRACK...BUT INCREASED POPS A BIT ALONG THE CENTRAL
OREGON COAST THROUGH THE NEAR TERM PER RADAR AND SATELLITE TRENDS.
THE FRONTAL BAND OF PRECIPITATION APPEARS SOMEWHAT DISJOINTED IN
APPEARANCE AND EXPECT RAINFALL TO BE INITIALLY LIGHT FOR THE NEXT FEW
HOURS...BEFORE INCREASING LATER TONIGHT THROUGH EARLY THU. LATEST
MODEL GUIDANCE SUGGESTS THAT THE SYSTEM MAY SPLIT N AND S...LEAVING
MANY PORTIONS OF THE AREA WITH ONLY OCCASIONAL LIGHT RAIN FROM MIDDAY
THU THROUGH THU EVENING. ALSO NUDGED FORECAST LOW TEMPERATURES FOR
TONIGHT A FEW DEGREES LOWER IN LINE WITH OBSERVATIONS AND GUIDANCE.
CULLEN
&&
.PREVIOUS DISCUSSION... /ISSUED 200 PM PST WED NOV 26 2014/
SHORT TERM...A WEAK COLD FRONT WAS OFFSHORE WED AFTERNOON...WITH
LAYERED CLOUDS SPREAD OUT AHEAD OF THE FRONT OVER THE PACIFIC NW. AS
THE UPPER RIDGE OVER THE REGION SHIFTS E TONIGHT AND THU THE FLOW
WILL TURN MORE TO THE SW...WITH THE FRONT SLOWLY PUSHING INLAND.
MODEL SOUNDINGS AGREE IN SHOWING MOISTURE INITIALLY IN THEMID AND
HIGH LEVELS...ABOVE 700MB. BY LATE TONIGHT THOUGH MOISTURE BEGINS TO
SPREAD IN IN THE LOWER LEVELS. DYNAMICS WITH THIS FRONT HOWEVER ON
THE WEAK SIDE...SO WILL BE SLOW TO INCREASE POPS OVERNIGHT INLAND
AREAS...WHILE THE COAST AND COAST RANGE WILL BENEFIT FROM AN
INCREASING LOW LEVEL SSW FLOW. WITH CLOUDS LIMITING RADIATIONAL
COOLING TONIGHT AND MUCH OF THE AREA STILL IN THE WARM SECTOR...
SHOULD BE ANOTHER UNSEASONABLY MILD NIGHT. THU THE FRONT APPEARS TO
STALL OVER THE REGION AS THE LOW OFFSHORE DIGS IN A BIT MORE. WITH
BAROCLINIC ZONE STALLED AND LOW LEVEL FLOW A LITTLE MORE ONSHORE
WILL TAKE POPS BACK UP TO LIKELY TO CATEGORICAL FOR MOST OF THE
REGION. ALTHOUGH THERE IS ONLY MODEST COOLING TO AIR MASS WITH THE
FRONT...CLOUDS AND EXPECTED OCCASIONAL LIGHT RAIN WILL LIMIT HIGH
TEMPS TO THE 50S MOST LOW ELEVATION AREAS.
LATE THU NIGHT...AND ESP FRI BETTER MOISTURE ARRIVES AS A NORTHERN
STREAM SHORT WAVE DROPS DOWN THROUGH BC WITH A TRUE COLD FRONT
DROPPING DOWN THE COAST AHEAD OF IT. MOIST ISENTROPIC LIFT IN THE
LOWER LEVELS IMPROVES AHEAD OF THE COLD FRONT AS WELL...BEST
DEPICTED IN MODEL 290K ISENTROPIC FIELDS. AS SUCH...POTENTIAL FOR
RAIN PICKS UP CONSIDERABLY BY FRI.
MODELS IN RELATIVELY GOOD AGREEMENT IN DEPICTING THE WESTERN
CANADIAN TROUGH DIGGING DOWN INTO THE PACIFIC NW STATES FRI NIGHT
AND SAT. ALL MODELS AT THIS POINT SHOWING A VIGOROUS CONTINENTAL
TYPE COLD FRONT MOVING S THROUGH SW WA AND NW OREGON FRI NIGHT.
PATTERN IS REMINISCENT OF A COLD FRONT FROM BACK ON 19 NOVEMBER 2003
THAT BROUGHT LOW ELEVATION SNOW TO INTERIOR N PARTS OF THE FORECAST
AREA. KEYS TO DOING SOMETHING SIMILAR RELY ON SOME OF THE
PRECIPITATION FALLING OVER AND BEHIND THE FRONT AS WELL AS STRONG
FRONTOGENETIC FORCING TO ALLOW FOR DYNAMIC COOLING. MODEL SOUNDINGS
AT THIS POINT INDICATE SNOW LEVEL FALLING RAPIDLY BEHIND THE FRONT
FRI NIGHT SUGGESTING AT LEAST A MIX OF RAIN AND SNOW POSSIBLE DOWN
TO FAIRLY LOW LEVELS. WHETHER IT WOULD BE COLD ENOUGH TO MIX SNOW AT
LOWEST ELEVATIONS IS ANYBODYS GUESS AT THIS POINT...BUT GIVEN THE
AGREEMENT IN MODELS AT THIS POINT WILL CARRY A MENTION OF MIXED RAIN
AND SNOW POSSIBLE FOR THE N PART OF THE AREA FRI NIGHT. SAT SEES A
RATHER COLD AIR MASS SETTLING IN OVER THE REGION BEHIND THE FRONT...
WITH A LINGERING CHANCE FOR SHOWERS...POTENTIALLY MIXED WITH SNOW IN
THE N...AS THE UPPER TROUGH MOVES THROUGH.
LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...MOST GUIDANCE
SUGGESTS THE UPPER TROUGH AXIS RESPONSIBLE FOR SATURDAYS MIXED
RAIN/SNOW SHOWERS WILL BE MOVING ACROSS THE CASCADES SAT NIGHT...
WITH ANY LINGERING SNOW SHOWERS COMING TO END OVERNIGHT. EXPECT SOME
CLEARING SAT NIGHT AS COLD HIGH PRESSURE BUILDS DOWN FROM BRITISH
COLUMBIA...WITH LOW TEMPS LIKELY GETTING WELL INTO THE 20S FOR MOST
SPOTS. WITH HIGH PRESSURE STRENGTHENING EAST OF THE CASCADES...
EXPECT STRONG EAST WINDS TO RAMP UP THROUGH THE GORGE SUNDAY MORNING
AND PERSIST FOR MUCH OF THE PERIOD THROUGH WEDNESDAY...WITH BREEZY
CONDITIONS SPILLING INTO THE PORTLAND/VANCOUVER METRO. MONDAY MAY BE
A BRIEF BREAK FROM THE WINDS AS A SYSTEM PASSES BY TO OUR NORTH.
MEANWHILE...A DISTURBANCE FROM THE ALEUTIANS IS EXPECTED TO CUT OFF
FROM THE MAIN PACIFIC JET AND SETTLE OFF THE CALIFORNIA COAST BY
SUNDAY...WHERE IT WILL LIKELY LINGER FOR A COUPLE DAYS. THERE IS A
CHANCE THIS SYSTEM COULD COME CLOSE ENOUGH TO SPREAD SOME PRECIP
NORTHWARD INTO OUR FORECAST AREA SUN NIGHT OR MON. THE 12Z GFS AND
CANADIAN MODELS ARE MORE AGGRESSIVE WITH THIS THAN THE ECMWF. IF
THIS OCCURS...THERE MAY BE SOME LIGHT FREEZING RAIN IN PORTIONS OF
THE WILLAMETTE VALLEY WITH SOME SNOW OR LIGHT FREEZING RAIN IN THE
GORGE. CUTOFF LOWS SUCH AS THIS ONE ARE NOTORIOUSLY DIFFICULT TO
FORECAST...AS MODELS STRUGGLE WITH THEM IN THE EXTENDED FORECAST
PERIOD. WHERE THIS UPPER LOW GOES WILL DICTATE THE WEATHER THROUGH
MIDWEEK...BUT TEMPS ARE EXPECTED TO SLOWLY MODERATE TUESDAY AND
WEDNESDAY. WEAGLE
&&
.AVIATION...VFR CONTINUES FOR NOW EXCEPT FOR KAST WHERE PASSING
RAIN BANDS HAVE BRIEFLY LOWERED THE CIGS TO AROUND 029. EXPECT THE
OVERALL CONDITIONS TO CONTINUE DETERIORATING OVER THE NEXT SEVERAL
HOURS AS THE OFFSHORE COLD FRONT CONTINUES ITS APPROACH. EVEN THEN
LATEST GUIDANCE IS NOT TERRIBLY PESSIMISTIC WITH FLIGHT
CONDITIONS AHEAD OF AND WITH THE FRONTAL PASSAGE. RADAR BACKS THIS
UP AS RETURNS ARE FAIRLY DISJOINTED IMPLYING A LACK OF
ORGANIZATION. AS SUCH...WILL CONTINUE THE PREVIOUS PACKAGES INTENT
OF SHOWING A LOWER AND WEAKLY CONVECTIVE DECK AFTER THE FRONT AND
LASTING THROUGH MOST OF THURSDAY. THIS APPEARS TO RESULT IN IFR
CIGS AT THE COAST AND MVFR CIGS AROUND 020 INLAND.
KPDX AND APPROACHES...VFR CONDITIONS TO PREVAIL THROUGH AT LEAST
12Z THU WITH VISUAL APPROACHED BECOMING IMPACTED SHORTLY
THEREAFTER AS THE DECK LOWERS BEYOND 040. WILL LIKELY SEE CIGS
BOTTOM OUT AROUND 020 CLOSER TO 18Z WITH LITTLE LIFT FOR THE
REMAINDER OF THE LOCAL CALENDAR DAY. /JBONK
&&
.MARINE...WINDS HAVE BEEN UNDER PERFORMING THUS FAR TONIGHT WITH
THE HRRR MODEL HAVING AS GOOD OF A HANDLE AS ANYTHING. DO EXPECT
COASTAL JET ENHANCEMENT AS THE FRONT NEARS TONIGHT BUT LAST FEW
RUNS OF THE HRRR ONLY INDICATE A VERY MARGINAL GALE GUST SCENARIO
FROM ABOUT 15 NM OUT TOWARDS SHORE. BEST WINDS WILL STAY WELL
ELEVATED OFF THE WATER SURFACE AS BROAD ATMOSPHERIC LIFT IS NOT
SUPPORTING THE HIGHER SPEEDS GETTING MIXED TO THE SURFACE. WILL
MAINTAIN THE GALE WARNING SINCE IT HAS ALREADY BEEN ISSUED.
BEHIND THE FRONT...HIGH-END SMALL CRAFT ADVISORY SPEEDS PERSIST
THU MORNING. LATEST MODEL RUNS SHOW 20-25 KT NW-N WIND DEVELOPING
OVER THE N WATERS FRI EVENING THEN SPREADING FURTHER S OVERNIGHT
AS A STRONG COLD FRONT DROPS SOUTH OUT OF CANADA. THE WIND TURNS
OFFSHORE SAT WITH POTENTIAL GUSTS 20 TO 30 KT NEAR GAPS IN THE
COASTAL TERRAIN. WIND SPEEDS RELAX SUN.
SEAS EXPECTED TO BUILD TO 10 FT THIS EVENING THEN REMAIN AT OR
ABOVE 10 FT THROUGH AT LEAST SAT MORNING. WAVE HEIGHTS DROP OFF
SAT AFTERNOON AS OFFSHORE FLOW DEVELOPS. JBONK/WEISHAAR
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WARNING UNTIL 4 AM PST THURSDAY FOR COASTAL WATERS FROM
CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 PM
PST THURSDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
Area Forecast Discussion
National Weather Service Spokane WA
1036 PM PST WED NOV 26 2014
.SYNOPSIS...
Mild and breezy weather is expected tonight and Thanksgiving with
areas of fog. Snow levels should rise above the mountain passes.
Motorists with plans to travel over the mountain passes should
experience good conditions this afternoon through Friday
afternoon. The arrival of a cold front Friday night into Saturday
will bring winter driving conditions to the mountain passes and
much cooler weather for the weekend.
&&
.DISCUSSION...
Evening update: The next couple mid-level disturbances will be
passing tonight and Thursday, shaking things up a little bit. This
will mean some increased threat of precipitation especially
around the mountain areas, and more peripherally around the
eastern Columbia Basin southward.
The broad area of dense fog has begun to decrease in some areas,
such as the Spokane area and northeast mountain valleys. While
some pockets of dense fog are still possible, it is not expected
to be widespread enough and wind are expected to increase some
overnight into Thursday AM. So the dense fog advisory was allowed
to expire in that region. It was however expanded over some of the
Upper Columbia Basin, Waterville Plateau and Moses Lake zones
through the night. HRRR models suggest this too will erode from
the southeast between 06-12Z, with the help of some mixing with
that first mid-level wave. This will be monitored and may
potentially be extended should this decreasing trend not
materialize.
Temperatures have been wonky in some spots this evening. At the
Spokane International Airport the temperature was 36 degrees near
sunset, but at this hour warmed to around 42 degrees, owing to the
fog/lower clouds breaking up some and the winds increased a bit
and mixing some of the warmer air aloft down. The 00Z sounding
showed a modest to strong low level inversion which makes this
warming not too surprising. However overall the confidence in
precise overnight lows is not high. Numbers should remain steady
or fall a degree or two from where they are now though. /J. Cote`
&&
.AVIATION...
06Z TAFS: The region will remain in a stable pattern, especially
near the surface, with a few weak disturbances riding over in the
mid-levels. Abundant low level moisture will keep some low clouds
and fog across the Basin, with localized IFR cigs/vis around MWH.
This is expected to gradually improve toward 12-15Z. Patchier fog
or mist will be possible around the remaining TAF sites, but with
the incoming disturbance we are expecting MVFR/VFR conditions.
Some threat of showers will be found around GEG to COE, PUW and
LWS late overnight into Thursday, with the better chances closer
to the ID panhandle and about the mountains. Winds will pick up
through the day Thursday, with some gusts over 20kts possible.
Late Thursday evening there will the threat of MVFR/IFR cigs
returning over eastern TAF sites.
NOTE: the VIS sensor at EAT is out of service so amendments to
VIS are not scheduled. /J. Cote`
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 39 49 41 46 27 30 / 30 30 20 70 60 10
Coeur d`Alene 36 47 41 45 29 31 / 30 40 40 80 90 20
Pullman 44 52 43 49 32 34 / 20 30 30 90 90 50
Lewiston 43 55 46 53 38 40 / 10 10 20 60 70 60
Colville 36 45 40 43 22 24 / 60 50 50 70 60 10
Sandpoint 33 45 38 42 26 26 / 70 60 70 80 90 20
Kellogg 37 44 39 41 30 31 / 60 80 60 90 100 50
Moses Lake 38 52 41 51 27 31 / 10 10 20 30 30 10
Wenatchee 39 47 41 48 29 30 / 10 10 30 30 20 10
Omak 34 43 37 41 16 20 / 30 20 20 20 20 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Dense Fog Advisory until 4 AM PST Thursday for Moses Lake Area-
Upper Columbia Basin-Waterville Plateau.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1122 PM CST WED NOV 26 2014
.UPDATE...
ISSUED AT 604 PM CST WED NOV 26 2014
STILL HAVE SOME LIGHT SNOW AND FLURRIES FALLING ACROSS THE AREA
EARLY THIS EVENING...BUT MOST OF THE ACCUMULATING SNOW HAS ALREADY
MOVED OUT OF THE ADVISORY AREA. HAVE THUS ALLOWED THE ADVISORY TO
EXPIRE AS SCHEDULED. FOR THE REST OF THE AREA...SOME SPOTS ACROSS
WESTERN AND CENTRAL WISCONSIN INTO NORTHEAST IOWA COULD STILL
RECEIVE ANOTHER HALF INCH OR SO OF ACCUMULATIONS THIS EVENING
UNTIL THE SNOW BAND MOVES OUT OF THE AREA. THIS LOOKS TO BE DRIVEN
BY SOME WEAK FORCING AHEAD OF A SHORT WAVE TROUGH MOVING ACROSS
MINNESOTA ALONG WITH SOME WEAK FRONTOGENESIS IN THE 1000-500 MB
LAYER. BOTH OF THESE FORCING SIGNALS MOVE PAST THE AREA AS THE
WAVE MOVES EAST THIS EVENING WITH THE 26.18Z NAM SUGGESTING THE
FRONTOGENESIS WEAKENS IN ADDITION TO MOVING OUT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 351 PM CST WED NOV 26 2014
AT 3 PM...A SURFACE LOW WAS LOCATED OVER NORTHEAST MISSOURI.
AN INVERTED TROUGH EXTENDS NORTH NORTHWEST OF THIS LOW THROUGH
CENTRAL IOWA INTO SOUTH CENTRAL MINNESOTA. FURTHER NORTHWEST AN
ARCTIC COLD FRONT EXTENDED FROM THE WESTERN TIP OF LAKE SUPERIOR
SOUTHEAST TO SIOUX FALLS SOUTH DAKOTA. TEMPERATURES AHEAD OF THIS
COLD FRONT WERE IN THE MID AND UPPER 20S. MEANWHILE IN THE WAKE OF
THIS FRONT...TEMPERATURES RANGED FROM 0 TO THE LOWER 20S. THE
COMBINATION OF LIFT ASSOCIATED WITH THE TROUGH AND THE COLD FRONT
PRODUCED SNOW ACROSS MUCH OF SOUTH CENTRAL AND SOUTHEAST MINNESOTA
AND EASTERN IOWA. THE HIGHEST SNOW TOTAL /MAINLY DUE TO THE AXIS
PIVOTING ACROSS THIS AREA FOR A LONG DURATION/ WAS 11 INCHES
8 MILES WEST OF FARIBAULT. OUR HIGHEST TOTAL IS 3.8 INCHES IN
MANTORVILLE MINNESOTA /DODGE COUNTY/.
FOR TONIGHT...THE 26.12Z MODELS ARE IN GOOD AGREEMENT THAT THE
TROUGH WILL CONTINUE TO PULL SOUTH AWAY FROM THE AREA AND TAKE
WITH IT THE INVERTED TROUGH WITH IT. THEY ALSO SHOW THAT THE
ARCTIC COLD FRONT WILL MOVE SOUTHEAST THROUGH THE AREA. THIS FRONT
WILL LIKELY EXTEND FROM WISCONSIN RAPIDS TO OELWEIN IOWA AROUND
MIDNIGHT AND WILL BE SOUTH OF THE FORECAST AREA BY 3 AM. THE
MODELS SHOW THAT THAT THE 900 TO 700 FRONTOGENESIS WILL QUICKLY
WEAKEN ACROSS THE AREA THIS EVENING. AS A RESULT...WENT WITH A
RAPIDLY DIMINISHING TREND IN THE SNOW. ADDITIONAL TOTALS WILL BE
UP TO AN INCH IN NORTHEAST IOWA AND SOUTHEAST MINNESOTA...AND FROM
A TRACE TO A HALF INCH IN WESTERN WISCONSIN. WITH IT STILL
SNOWING...WILL JUST LET THE WINTER WEATHER ADVISORY CONTINUE
THROUGH 6 PM.
WITH STRONG COLD AIR ADVECTION IN THE WAKE OF THIS FRONT...EXPECT
HIGH TEMPERATURES FOR THANKSGIVING TO OCCUR BETWEEN MIDNIGHT AND
3 AM TONIGHT. NAEFS STANDARD 850 MB TEMPERATURE ANOMALIES ARE
RUNNING AROUND 2 STANDARD DEVIATIONS BELOW NORMAL. AS A
RESULT...EXPECT HIGH TEMPERATURES TO RANGE FROM NEAR 10 TO 25.
THIS WILL BE THE COLDEST THANKSGIVING IN SOUTHEAST MINNESOTA AND
NORTHEAST IOWA SINCE 1985...AND THE COLDEST IN WESTERN WISCONSIN
SINCE 1958. MORE ON THIS CAN BE FOUND IN THE CLIMATE SECTION OF
THIS PRODUCT.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 351 PM CST WED NOV 26 2014
ON THURSDAY NIGHT AND FRIDAY...MODERATE TO STRONG 925 TO 700 MB
WARM AIR ADVECTION WILL DEVELOP ACROSS THE AREA AS A SHORT WAVE
TROUGH MOVES EAST ACROSS NORTHERN MINNESOTA. IT CONTINUES TO LOOK
LIKE THIS SYSTEM WILL PRODUCE BETWEEN 1.5 AND 3 INCHES ALONG AND
NORTH OF INTERSTATE 94...AND FROM A TRACE TO 1.5 INCHES SOUTH OF
THIS INTERSTATE. SOUNDINGS CONTINUE TO SHOW THAT DRY AIR ABOVE
850 MB WILL MOVE NORTHEAST INTO THE AREA FROM THE CENTRAL PLAINS
ON FRIDAY. THIS DRY AIR WILL SHUTOFF ICE CRYSTAL SEEDING FROM
ALOFT. HOWEVER THERE APPEARS TO BE A DEEP ENOUGH COLD LAYER NEAR
THE SURFACE THAT SOME SNOW COULD STILL DEVELOP INITIALLY...AND
THEN AS THIS LAYER WARMS UP THIS PRECIPITATION COULD POTENTIALLY
SHIFT OVER TO SOME LIGHT FREEZING DRIZZLE...BUT A BIT CONCERNED
THAT BY THIS TIME THERE MAY BE ENOUGH DRY IN THE LOW LEVELS TO
PRECLUDE THIS FROM HAPPENING.
ON FRIDAY NIGHT...THE NAM DEVELOPS FREEZING RAIN NEAR THE
INTERSTATE 90 CORRIDOR. MEANWHILE THE OTHER DETERMINISTIC MODELS
HAVE THE AREA DRY...SO TRENDED THE FORECAST TOWARD THEM. ANOTHER
ISSUE ON FRIDAY NIGHT IS THAT THE LOW TEMPERATURES LOOK TOO COLD
CONSIDERING SOUTHWEST WIND OF 10 TO 15 MPH AND THE MODELS LOOKING
LIKE THEY HAVE TOO MUCH SNOW INITIALIZED IN THEM. THE NAM IN
PARTICULAR IS ABOUT 2 TO 3 INCHES TOO HIGH WITH ITS SNOW DEPTH
ALREADY. DUE TO THIS...RAISED THEM A FEW DEGREES AND ALSO RAISED
SATURDAY MAXIMUM TEMPERATURES TOO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1121 PM CST WED NOV 26 2014
SATELLITE AND SURFACE OBSERVATIONS INDICATE THE SKIES ARE CLEARING
ACROSS MINNESOTA FASTER THAN EXPECTED AS THE SURFACE HIGH BUILDS
IN. TIMING THE CLEARING THROUGH OFF THE SATELLITE PUTS IT INTO
KRST AROUND 07Z AND BETWEEN 08Z AND 09Z FOR KLSE. UNTIL THE
CLEARING ARRIVES...THE MVFR CEILINGS WILL REMAIN IN PLACE ALONG
WITH SOME FLURRIES. THE NEXT SYSTEM WILL RAPIDLY APPROACH THE
REGION THURSDAY EVENING. THE WARM AIR ADVECTION OUT AHEAD OF THIS
SYSTEM SHOULD BE ENOUGH TO GENERATE SOME MID LEVEL CLOUDS DURING
THE EVENING BUT A RAPID EXPANSION AND LOWERING OF THE CLOUDS
SHOULD OCCUR AFTER 06Z FRIDAY.
&&
.CLIMATE...THANKSGIVING
ISSUED AT 351 PM CST WED NOV 26 2014
WITH A HIGH TEMPERATURE NEAR 10 DEGREES...ROCHESTER MINNESOTA WILL
BE WITHIN THE TOP 5 FOR THEIR COLDEST THANKSGIVING HIGH
TEMPERATURE. THEY ARE...
1/ 7F 1930
2/ 12F 1985
3/ 14F 1952
4/ 14F 1886
5/ 17F 1956
17F 1919
IT WILL BE ONLY THE 10TH TIME THAT ROCHESTER HAS BEEN 19 DEGREES
OR COLDER ON THANKSGIVING. THE LAST TIME IT OCCURRED WAS 1985.
IN LA CROSSE WISCONSIN...THERE IS STILL SOME QUESTION ON WHETHER
THE HIGH FOR THE DAY WILL BE IN THE TEENS OR NOT. AT MIDNIGHT...THE
HRRR...NAM...SREF...AND RAP HAVE THE HIGH TEMPERATURE BETWEEN 20
AND 22F. MEANWHILE BOTH THE GFS AND ECMWF...HAS A MIDNIGHT HIGH
OF 18F. THIS WOULD PLACE THIS THANKSGIVING IN THE 9 TO 15 RANK.
THEY ARE...
7/ 17F 1919
17F 1952
9/ 19F 1958
19F 1956
19F 1952
12/ 20F 1938
20F 1905
20F 1881
15/ 21F 1903
16/ 23F 1877
THE COLDEST IS 4 DEGREES IN 1872. OUR TEMPERATURE RECORDS FOR
LA CROSSE STARTED JUST OVER A MONTH BEFORE THIS RECORD WAS SET ON
OCTOBER 15 1872. IF WE ARE IN THE TEENS FOR A HIGH TEMPERATURE IT
WILL ONLY BE THE 11TH TIME THAT THIS HAS OCCURRED. IT WILL
DEFINITELY BE THE COLDEST THANKSGIVING AS FAR AS HIGH TEMPERATURE
SINCE 1958 /19F/.
ALSO THIS COULD POTENTIALLY BE THE 21ST CONSECUTIVE THANKSGIVING
WITHOUT MEASURABLE PRECIPITATION IN LA CROSSE. THIS STRETCH IS THE
LONGEST. PRIOR TO THIS STRETCH...THE RECORD WAS 6 YEARS /1900-1905
1909-14 AND 1986-91/.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...04
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
CLIMATE...BOYNE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1020 PM MST WED NOV 26 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 416 PM MST WED NOV 26 2014
SNOW SHOWERS CONTINUE THIS AFTERNOON ACROSS THE NEBRASKA PANHANDLE
ALONG THE LEADING EDGE OF LOW TO MID-LEVEL WAA MOVING IN FROM WEST
TO EAST. LAPS SOUNDINGS SHOWS LLVL LAPSE RATES ARE ALSO A BIT
STEEP...WHICH IS LIKELY CONTRIBUTING TO SHOWER DEVELOPMENT AS
WELL. MODELS SHOW THIS ACTIVITY STEADILY WANING AROUND
SUNSET...ALTHOUGH A FEW SHOWERS MAY PERSIST THROUGH ABOUT 03Z.
WINDS OVER THE SOUTHERN LARAMIE RANGE ARE INCREASING ALTHOUGH THE
SFC FRONT IS SLOWER TO SHIFT EAST THAN PREVIOUS THOUGHT SO
WIDESPREAD HIGH WINDS HAVE NOT QUITE MATERIALIZED. SIMILARLY FOR
BORDEAUX...WINDS ARE STILL OUT OF THE SOUTHEAST AT THIS HOUR. IT
APPEARS PRESSURE FALLS OVER THE MOUNTAINS OF COLORADO HAVE KEPT
THE FRONT FROM SHIFTING EAST OUT INTO THE PLAINS...BUT EXPECTING
THESE PRESSURE FALLS OVER THE MOUNTAINS TO EASE OVER THE NEXT FEW
HOURS WHICH SHOULD ALLOW THE FRONT TO FINAL TREK EAST.
THEREFORE...STILL THINKING THAT HIGH WINDS WILL DEVELOP AT LEAST
FOR A SHORT PERIOD OVER THE SOUTHERN LARAMIE RANGE IN THE EVENING
AND AT BORDEAUX LATER TONIGHT...AND SO WILL KEEP THE WARNING IN
PLACE FOR THE NEAR TERM. EXTENDED IT THROUGH THURSDAY AFTERNOON AS
THE POSSIBILITY EXISTS FOR STRONG WINDS TO PERSIST THROUGH THE
DAY.
THE CAG-CPR GRADIENT REMAINS STRONG THROUGH THURSDAY...AND REALLY
THROUGH FRIDAY AS WELL...WITH WINDS OF 50+ KTS PROGGED TO BE JUST
OFF THE SURFACE THROUGH THIS TIME WITH STRONG ZONAL FLOW SETTING
UP OVERHEAD. THE OVERALL PATTERN REMAINS VERY FAVORABLE FOR A LONG
DURATION HIGH WIND EVENT THROUGH FRIDAY FOR THE WIND PRONE AREAS
ALONG AND WEST OF I-25...HOWEVER AM CONCERNED ABOUT MODELS SHOWING
A STRONG AND PERSISTENT INVERSION NEAR THE SURFACE WHICH COULD
PREVENT THESE STRONGER WINDS FROM REACHING THE SURFACE. WAA WITH
RISING HEIGHTS ALOFT IN ZONAL FLOW COMBINED WITH A SHARP MIDLEVEL
THERMAL GRADIENT DEVELOPING ALONG THE ROCKIES ARE CONTRIBUTING TO
THIS INVERSION. THE INVERSION WILL BE COMPETING WITH DEEP LAYER
SUBSIDENCE ON THE ANTICYCLONIC SIDE OF THE JET AND WITH AN ACTIVE
MOUNTAIN WAVE IN PLACE TOMORROW AND FRIDAY. SO...TOUGH CALL WHAT
TO DO EXACTLY WITH HIGH WIND HIGHLIGHTS EXACTLY. FEEL MORE
CONFIDENT THAT THE ARLINGTON AREA WILL SEE PERSISTENT STRONG WINDS
THROUGH THURSDAY AND FRIDAY BEING A HIGHER ELEVATION SITE AND
CLOSER TO MOUNTAIN WAVE/GAP INFLUENCES...BUT FURTHER EAST AT
BORDEAUX AND MAYBE EVEN THE SOUTHERN LARAMIE RANGE/FOOTHILLS...THE
INVERSION MAY HOLD STRONG ENOUGH TO KEEP THE WINDS ALOFT. SO FOR
NOW...MAINTAINED THE HIGH WIND WARNING THROUGH TOMORROW AFTERNOON
FOR ALL WIND PRONE ZONES AS ITS DEFINITELY NOT OUT OF THE QUESTION
THAT THE STRONG WINDS WILL BE FORCED TO THE SURFACE IN THE MORNINGAND
AGAIN IN THE AFTERNOON. WILL REEVALUATE ON LATER SHIFTS FOR THE
NEED FOR FURTHER HIGHLIGHTS THROUGH FRIDAY. TEMPERATURES WILL WARM
BACK INTO THE 40S AND 50S FROM WEST TO EAST...WITH EVEN A FEW 60S
EXPECTED ACROSS THE PLAINS ON FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 416 PM MST WED NOV 26 2014
A WARM START TO THE EXTENDED FCST PERIOD WITH FLAT/ZONAL FLOW ALOFT
IN PLACE OVER MUCH OF THE NORTHERN CONUS. WITH ANY NOTABLE WEATHER
FEATURES WELL TO THE NORTH...BOTH GFS AND ECMWF SHOW ANOTHER DAY OF
H7 TEMPS AS WARM AS 4 DEG C AT 18Z SAT ALONG AND SOUTHEAST OF A LINE
FROM CHEYENNE TO ALLIANCE. WESTERLY DOWNSLOPE FLOW WOULD MOST LIKELY
ENHANCE WARMING WHICH GIVES CREDENCE TO MOS GUIDANCE IN THE LOW
TO MID 60S OVER MUCH OF THE PLAINS. BUMPED UP HIGHS SEVERAL
DEGREES ON SAT AS BOTH THE MEX AND ECM SHOWED TEMPS SOME 3-5 DEG F
WARMER THAN THE PREVIOUS FCST. STRONG WINDS COULD BE LINGERING IN
THE WIND PRONE AREAS THROUGH AT LEAST EARLY SUN AS 850 AND 700 MB
CAG-CPR GRADIENTS LOOK TO REMAIN AROUND 60 METERS PER THE GFS
ALONG WITH RATHER STRONG FLOW ALOFT AT H75. STRONG MID LEVEL
SHORTWAVE DIGS INTO THE PACIFIC NORTHWEST LATE SAT AND INTO
NORTHERN WY ON SUN. THIS FORCES A STRONG SFC COLD FRONT SOUTHWARD
INTO THE NORTHERN ZONES AND GIVES WAY TO A SLIGHT COOLING TREND BY
LATE IN THE WEEKEND. UPPER-LEVEL SUPPORT IS EXPECTED TO STAY OUT
OF OUR NECK OF THE WOODS WITH THE BEST PVA WELL TO THE NORTH...SO
DO NOT EXPECT MUCH MORE THAN ISOLATED TO SCATTERED SNOW SHOWERS
WITH THE FROPA. GFS HAS BEEN TRENDING A BIT TOWARD THE COLDER
ECMWF...SO HAVE MAINTAINED THE PREVIOUS FCST WITH HIGHS ABOUT 15
TO 20 DEGREES COOLER THAN SAT GIVEN H7 TEMPS PLUNGING TOWARD THE
UPPER TEENS BELOW ZERO C. THE MODELS DIFFER IN THE TIMING OF
ANOTHER SHORTWAVE MOVING INTO THE WESTERN US LATE IN THE PERIOD.
IN GENERAL EXPECT PCPN CHANCES TO SLOWLY INCREASE FROM WEST TO
EAST BY LATE TUE OR EARLY WED. UNTIL THEN...DRY WESTERLY H25 FLOW
WITH MODEST 700-300 MILLIBAR MOISTURE PROGS WILL LIMIT RAIN/SNOW
SHOWER POTENTIAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1017 PM MST WED NOV 26 2014
LATEST HRRR GUIDANCE USED FOR THE 06Z TAF SUITE. HAS IFR/LIFR
PUSHING OFF TO THE EAST INTO CENTRAL NEBRASKA STARTING OFF. HAS
BEEN DOING WELL THIS EVENING...SO DID NOT WANT TO STRAY TO FAR
FROM ITS GUIDANCE. AM CONCERNED THOUGH WITH OUR PANHANDLE AIRPORTS
AS THEY HAVE BEEN UP AND DOWN IN LOW CEILINGS. WENT WITH A SCT002
AT KBFF AND KAIA THROUGH 09Z OR SO BEFORE WINDS BEGIN TO PICK UP
AND SCOUR OUT THE LOW LEVEL MOISTURE. WINDY AGAIN THURSDAY.
&&
.FIRE WEATHER...
ISSUED AT 416 PM MST WED NOV 26 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH THE END OF THE WEEK. MILDER
TEMPERATURES ARE EXPECTED ON THURSDAY THROUGH SATURDAY WITH
MINIMUM AFTERNOON HUMIDITY VALUES DROPPING INTO THE 20-30 PERCENT
RANGE FOR AREAS TO THE EAST OF THE LARAMIE RANGE. WINDY CONDITIONS
WILL PERSIST ACROSS SOUTHEAST WYOMING THROUGH SATURDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL 5 PM MST THURSDAY FOR WYZ106-110-116-117.
NE...NONE.
&&
$$
SHORT TERM...RJM
LONG TERM...CLH
AVIATION...GCC
FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS ALBANY NY
1000 AM EST THU NOV 27 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL BRING SOME SCATTERED SNOW SHOWERS
TO REGION TODAY INTO TONIGHT. HIGH PRESSURE WILL RIDGE IN BRIEFLY
FOR FRIDAY WITH BELOW NORMAL TEMPERATURES. MILDER AIR ATTEMPTS TO
BUILD INTO THE REGION THIS WEEKEND...HOWEVER...IT WILL BE
ACCOMPANIED BY CLOUD COVER AND THE CHANCE FOR LIGHT SNOW OR RAIN
SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM EST...RADAR RETURNS SHOW THAT NUMEROUS SNOW SHOWERS
WILL BE MOVING INTO THE EASTERN CATSKILLS AND HAVE RAISED POPS THERE
TO LIKELY. WILL WAIT UNTIL LATER UPDATES TO SEE IF WE NEED HIGHER
POPS IN THE LOWER TERRAIN AREAS.
PREV DISC...
THE NOR`EASTER THAT PRODUCED A SIGNIFICANT SNOWFALL FOR THE REGION
WAS QUICKLY DEPARTING OFF THE COAST OF MAINE THIS MORNING /WAS
993MB AS OF 08Z/. DEFORMATION AXIS THAT MOVED ACROSS THE NORTHERN
2/3RDS OF THE REGION WAS TOO QUICKLY LIFTING NORTHEAST ACROSS NEW
ENGLAND AS SEEN IN THE COLDER IR SATELLITE IMAGERY CLOUD TOPS.
THROUGH THE NEXT FEW HOURS...WE CONTINUE TO WATCH THE POTENTIAL
MESOSCALE MOHAWK-HUDSON VALLEY CONVERGENCE AS METARS AND
STREAMLINE ANALYSIS POINT TOWARD WINDS CONVERGING INTO THE CAPITAL
REGION...HOWEVER...IT WAS ALSO FIGHTING SUBSIDENCE IN THE WAKE OF
THE NOR`EASTER. FOR NOW...WE WILL CONTINUE WITH CHC-SLIGHT CHC POPS
THROUGH THE EARLY MORNING HOURS.
H2O VAPOR LOOP DEPICTS A DEEP TROUGH ACROSS THE EASTERN 2/3RDS OF
NOAM. A COUPLE OF RATHER POTENT SHORT WAVES WERE OBSERVED...ONE
APPROACHING THE OHIO RIVER VALLEY AND THE OTHER TRACKING INTO THE
WESTERN GREAT LAKES. TEMPERATURES ALOFT WITH THESE FEATURES ARE
QUITE COLD WITH SUB -30C AIR AT H500 AND ABOVE. NCEP MODEL SUITE
AND INTERNATIONAL GUIDANCE ARE IN GOOD AGREEMENT WITH TRACKING
THESE WAVES ACROSS THE CWFA TODAY. QG FORCING WAS PRONOUNCED LATE
THIS MORNING INTO THE AFTERNOON HOURS ALONG WITH STEEPENING LAPSE
RATES THAT SHOULD RESULT WITH AN INCREASE IN SNOW SHOWER ACTIVITY
COVERAGE. 4KM SPC AND HRRR REFLECTIVITIES DO INDICATE AN INCREASE
IN COVERAGE OF SNOW SHOWERS AS WE WILL REFLECT THIS IN THE
GRIDS/FORECAST WITH RAISING POPS. MOST OF THE HIGHER POP VALUES
WILL BE INTO THE TERRAIN WITH OROGRAPHIC LIFTING. AS FOR
ADDITIONAL ACCUMULATIONS...WE COULD SEE AN ADDITIONAL INCH OR SO.
GUIDANCE TEMPERATURES ARE VERY CLOSE...HOWEVER...WITH FRESH SNOW
COVER WE WILL LEAN TOWARD A SLIGHTLY COOLER VALUES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
RIDGING WILL BE BUILDING INTO THE REGION...HOWEVER...LAKE EFFECT
SNOW SHOWERS DOWNWIND OF LAKE ONTARIO WILL THE MAIN WEATHER ISSUE
ON FRIDAY. LATEST NAM12 SUGGESTS THE LOW LEVEL BOUNDARY LAYER
WINDS WILL INITIALLY BE NORTHWEST...BUT AS THE RIDGE
BUILDS...THOSE WINDS BE BACKING WITH TIME. THIS WOULD SUGGEST LAKE
EFFECT ACTIVITY THAT WILL BE WEST OF THE REGION INITIALLY TO
MIGRATE INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN
DACKS. DUE TO THE MIGRATORY NATURE...THE INLAND EXTENT IS EXPECTED
TO BE LIMITED AS WE WILL KEEP POPS INTO THE CHC-SCT CATEGORY.
OTHERWISE...THE REMAINDER OF THE REGION WILL BE RATHER TRANQUIL
WITH SOME PEAKS OF SUNSHINE. AS H850 TEMPS WILL RANGE BETWEEN -12C
TO -14C...IT WILL BE UNSEASONABLY COOL FOR LATE NOVEMBER.
FRIDAY NIGHT INTO SATURDAY...HIGH PRESSURE MOVES OFF THE ATLANTIC
SEABOARD AS STORM ATTEMPTS TO ORGANIZE ACROSS THE NORTHERN PLAINS
AND GREAT LAKES REGION. THIS WILL PLACE OUR REGION INTO A WARM
ADVECTION REGIME. ALTHOUGH...LOW LEVEL MOISTURE WILL REMAIN RATHER
HIGH TO KEEP CLOUDS IN THE FORECAST. AS FOR PRECIP
POTENTIAL...BROAD ISENTROPIC LIFT WILL BE UNDERWAY WITH THE BEST
LOWERING OF THE CPD/S TO BE NORTH AND WEST OF THE CWFA.
HOWEVER...SINCE THE LOW LEVELS WILL BECOME RATHER HIGH IN MOISTURE
CONTENT...WE WILL CONTINUE WITH THE CHC POPS OF LIGHT
PRECIPITATION THROUGH THE PERIOD. MOST OF THIS PRECIP SHOULD FALL
AS WINTER TYPE BUT SOME OF THE WARMER VALLEY LOCATIONS MAY
EXPERIENCE A MIX OF RAIN/SNOW SHOWERS.
GUIDANCE TEMPERATURES DIVERGE THROUGH THE SHORT TERM AND PER THE
CURRENT SNOW PACK...WE WILL LEAN TOWARD THE COOLER SIDE OF THE
GUIDANCE ENVELOPE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
LONG TERM PERIOD CHARACTERIZED BY CHANGEABLE WEATHER AND WIDELY
VARYING TEMPERATURES AS A SERIES OF FRONTS CROSS EASTERN NEW YORK
AND WESTERN NEW ENGLAND.
FOR SUNDAY...A WARM FRONT WILL BE CROSSING THE FORECAST AREA. FOR
NOW HAVE SLIGHT CHANCE POPS OVER MOST OF THE AREA WITH CHANCE POPS
OVER SOUTHWESTERN ADIRONDACKS AS BEST FORCING FOR ANY PRECIPITATION
MOVES NORTH OF THE AREA. AFTER A COLD THANKSGIVING WEEKEND...
TEMPERATURES SHOULD MODERATE BY LATE ON SUNDAY WITH HIGHS 40S
VALLEYS AND SOME 30S HIGHEST ELEVATIONS.
ONE OF THE MORE TRICKY PARTS OF THE EXTENDED FORECAST IS THE LOW
TEMPERATURE FORECAST ON MONDAY MORNING. THERE WILL LIKELY STILL BE
SIGNIFICANT SNOW COVER ACROSS THE AREA. IF WE CAN DECOUPLE THE
BOUNDARY LAYER FROM THE GRADIENT WIND FLOW...WITH CLEARING SKIES
TOWARD DAYBREAK...TEMPERATURES MAY FALL A GOOD TEN TO FIFTEEN
DEGREES BELOW FREEZING. FOR NOW WENT WITH LOWS AROUND FREEZING AND
THIS WILL LIKELY BE ADJUSTED AS WE GET LATER IN THE WEEKEND. A COLD
FRONT WILL CROSS THE AREA LATER MONDAY...BUT TEMPERATURES SHOULD
ONCE AGAIN REACH THE 40S IN THE VALLEYS BEFORE THE FRONT MOVES
THROUGH. A LITTLE COOLER IN THE HILLS WITH UPPER 30S FOR HIGHS.
TUESDAY LOOKS GENERALLY FAIR AND COLD BEHIND THE COLD FRONT. LOWS IN
THE TEENS AND TWENTIES AND HIGHS IN THE 20S AND 30S.
BY WEDNESDAY THE NEXT WARM FRONT IS SURGING TOWARDS THE AREA. THERE
MAY BE A BURST OF WARM ADVECTION PRECIPITATION AROUND DAYBREAK
WEDNESDAY MORNING. THIS COULD BE A MIXED BAG OF PRECIP TYPES. THE
REST OF THE DAY LOOKS CLOUDY WITH MODERATING TEMPERATURES AND
ANOTHER COLD FRONT APPROACHING QUICKLY FROM THE WEST. AS THIS COLD
FRONT MOVES THROUGH WEDNESDAY NIGHT...THERE MAY BE SOME RAIN SHOWERS
CHANGING TO SNOW SHOWERS. ANOTHER SHOT OF COLD AIR BEHIND THE FRONT
FOR THURSDAY AND FRIDAY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
MVFR CONDITIONS ARE OCCURRING ACROSS MOST OF THE ALBANY FORECAST
AREA THIS MORNING. THE EXCEPTION IS KPOU WHICH IS CURRENTLY VFR
BUT HAS BEEN BOUNCING BETWEEN VFR AND IFR DUE TO FOG. A BRIEF
PERIOD OF VFR IS EXPECTED AT THE TAF SITES THIS MORNING BEFORE A
VIGOROUS COLD UPPER LEVEL TROUGH BRINGS ANOTHER CHANCE FOR SNOW
LATER TODAY TO THE AREA WITH MVFR CONDITIONS EXPECTED AT ALL THE
TAF SITES BY LATER THIS AFTERNOON OR THIS EVENING. A LIGHT
ACCUMULATING SNOW IS AGAIN POSSIBLE WITH THIS SYSTEM. IMPROVEMENT
TO VFR CONDITIONS EXPECTED BY MID MORNING FRIDAY.
WINDS WILL BE NORTHWESTERLY AT LESS THAN 10 KTS THROUGH FRIDAY.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...FZRA.
SUNDAY NIGHT: SLIGHT CHANCE OF SHRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SLEET.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THROUGH THE
WEEKEND.
ADDITIONAL LIGHT PRECIPITATION AMOUNTS ARE EXPECTED WITH BASIN
AVERAGES AT A TENTH OF AN INCH OR LESS EXPECTED.
MILDER TEMPS ARE POSSIBLE SUNDAY WITH SOME SNOW MELT. HOWEVER...
TEMPERATURES ARE EXPECTED TO COOL OFF QUICKLY DURING MONDAY WITH
THE PASSAGE OF A STRONG COLD FRONT.
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.
&&
.CLIMATE...
A RECORD SNOWFALL OF 9.6 INCHES WAS SET AT ALBANY NY YESTERDAY.
THIS BREAKS THE OLD RECORD OF 4.9 SET IN 1888. ALSO...THIS PLACES
THE STORM INTO ONE OF THE TOP 10 SNOWSTORMS FOR NOVEMBER FOR ALBANY.
WITH ADDITIONAL SNOWFALL EXPECTED THIS WEEKEND...WE WILL ALSO WATCH
HOW MUCH ADDS UP TO SEE WHERE WE FINISH UP FOR SNOW BY THE END OF THE
MONTH.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM/WASULA
LONG TERM...SND
AVIATION...SND
HYDROLOGY...KL/BGM/WASULA
CLIMATE...ALY
AREA FORECAST DISCUSSION
NWS ALBANY NY
645 AM EST THU NOV 27 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL BRING SOME SCATTERED SNOW SHOWERS
TO REGION TODAY INTO TONIGHT. HIGH PRESSURE WILL RIDGE IN BRIEFLY
FOR FRIDAY WITH BELOW NORMAL TEMPERATURES. MILDER AIR ATTEMPTS TO
BUILD INTO THE REGION THIS WEEKEND...HOWEVER...IT WILL BE
ACCOMPANIED BY CLOUD COVER AND THE CHANCE FOR LIGHT SNOW OR RAIN
SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM EST...RADAR RETURNS ARE INCREASING UPSTREAM AS THAT
SHORT WAVE APPROACHES. IR SATELLITE IMAGERY SUPPORTS COOLING CLOUD
TOPS WITH THE EXPECTATIONS OF MORE SNOW DEVELOPING ACROSS THE REGION
TODAY. DID RAISE DEWPOINTS A FEW DEGREES BASED ON OBSERVATIONS AND
TEMPERATURES WILL LIKELY RISE EVER SO SLIGHTLY THROUGH THE DAY.
PREV DISC...
THE NOR`EASTER THAT PRODUCED A SIGNIFICANT SNOWFALL FOR THE REGION
WAS QUICKLY DEPARTING OFF THE COAST OF MAINE THIS MORNING /WAS
993MB AS OF 08Z/. DEFORMATION AXIS THAT MOVED ACROSS THE NORTHERN
2/3RDS OF THE REGION WAS TOO QUICKLY LIFTING NORTHEAST ACROSS NEW
ENGLAND AS SEEN IN THE COLDER IR SATELLITE IMAGERY CLOUD TOPS.
THROUGH THE NEXT FEW HOURS...WE CONTINUE TO WATCH THE POTENTIAL
MESOSCALE MOHAWK-HUDSON VALLEY CONVERGENCE AS METARS AND
STREAMLINE ANALYSIS POINT TOWARD WINDS CONVERGING INTO THE CAPITAL
REGION...HOWEVER...IT WAS ALSO FIGHTING SUBSIDENCE IN THE WAKE OF
THE NOR`EASTER. FOR NOW...WE WILL CONTINUE WITH CHC-SLIGHT CHC POPS
THROUGH THE EARLY MORNING HOURS.
H2O VAPOR LOOP DEPICTS A DEEP TROUGH ACROSS THE EASTERN 2/3RDS OF
NOAM. A COUPLE OF RATHER POTENT SHORT WAVES WERE OBSERVED...ONE
APPROACHING THE OHIO RIVER VALLEY AND THE OTHER TRACKING INTO THE
WESTERN GREAT LAKES. TEMPERATURES ALOFT WITH THESE FEATURES ARE
QUITE COLD WITH SUB -30C AIR AT H500 AND ABOVE. NCEP MODEL SUITE
AND INTERNATIONAL GUIDANCE ARE IN GOOD AGREEMENT WITH TRACKING
THESE WAVES ACROSS THE CWFA TODAY. QG FORCING WAS PRONOUNCED LATE
THIS MORNING INTO THE AFTERNOON HOURS ALONG WITH STEEPENING LAPSE
RATES THAT SHOULD RESULT WITH AN INCREASE IN SNOW SHOWER ACTIVITY
COVERAGE. 4KM SPC AND HRRR REFLECTIVITIES DO INDICATE AN INCREASE
IN COVERAGE OF SNOW SHOWERS AS WE WILL REFLECT THIS IN THE
GRIDS/FORECAST WITH RAISING POPS. MOST OF THE HIGHER POP VALUES
WILL BE INTO THE TERRAIN WITH OROGRAPHIC LIFTING. AS FOR
ADDITIONAL ACCUMULATIONS...WE COULD SEE AN ADDITIONAL INCH OR SO.
GUIDANCE TEMPERATURES ARE VERY CLOSE...HOWEVER...WITH FRESH SNOW
COVER WE WILL LEAN TOWARD A SLIGHTLY COOLER VALUES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
RIDGING WILL BE BUILDING INTO THE REGION...HOWEVER...LAKE EFFECT
SNOW SHOWERS DOWNWIND OF LAKE ONTARIO WILL THE MAIN WEATHER ISSUE
ON FRIDAY. LATEST NAM12 SUGGESTS THE LOW LEVEL BOUNDARY LAYER
WINDS WILL INITIALLY BE NORTHWEST...BUT AS THE RIDGE
BUILDS...THOSE WINDS BE BACKING WITH TIME. THIS WOULD SUGGEST LAKE
EFFECT ACTIVITY THAT WILL BE WEST OF THE REGION INITIALLY TO
MIGRATE INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN
DACKS. DUE TO THE MIGRATORY NATURE...THE INLAND EXTENT IS EXPECTED
TO BE LIMITED AS WE WILL KEEP POPS INTO THE CHC-SCT CATEGORY.
OTHERWISE...THE REMAINDER OF THE REGION WILL BE RATHER TRANQUIL
WITH SOME PEAKS OF SUNSHINE. AS H850 TEMPS WILL RANGE BETWEEN -12C
TO -14C...IT WILL BE UNSEASONABLY COOL FOR LATE NOVEMBER.
FRIDAY NIGHT INTO SATURDAY...HIGH PRESSURE MOVES OFF THE ATLANTIC
SEABOARD AS STORM ATTEMPTS TO ORGANIZE ACROSS THE NORTHERN PLAINS
AND GREAT LAKES REGION. THIS WILL PLACE OUR REGION INTO A WARM
ADVECTION REGIME. ALTHOUGH...LOW LEVEL MOISTURE WILL REMAIN RATHER
HIGH TO KEEP CLOUDS IN THE FORECAST. AS FOR PRECIP
POTENTIAL...BROAD ISENTROPIC LIFT WILL BE UNDERWAY WITH THE BEST
LOWERING OF THE CPD/S TO BE NORTH AND WEST OF THE CWFA.
HOWEVER...SINCE THE LOW LEVELS WILL BECOME RATHER HIGH IN MOISTURE
CONTENT...WE WILL CONTINUE WITH THE CHC POPS OF LIGHT
PRECIPITATION THROUGH THE PERIOD. MOST OF THIS PRECIP SHOULD FALL
AS WINTER TYPE BUT SOME OF THE WARMER VALLEY LOCATIONS MAY
EXPERIENCE A MIX OF RAIN/SNOW SHOWERS.
GUIDANCE TEMPERATURES DIVERGE THROUGH THE SHORT TERM AND PER THE
CURRENT SNOW PACK...WE WILL LEAN TOWARD THE COOLER SIDE OF THE
GUIDANCE ENVELOPE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
LONG TERM PERIOD CHARACTERIZED BY CHANGEABLE WEATHER AND WIDELY
VARYING TEMPERATURES AS A SERIES OF FRONTS CROSS EASTERN NEW YORK
AND WESTERN NEW ENGLAND.
FOR SUNDAY...A WARM FRONT WILL BE CROSSING THE FORECAST AREA. FOR
NOW HAVE SLIGHT CHANCE POPS OVER MOST OF THE AREA WITH CHANCE POPS
OVER SOUTHWESTERN ADIRONDACKS AS BEST FORCING FOR ANY PRECIPITATION
MOVES NORTH OF THE AREA. AFTER A COLD THANKSGIVING WEEKEND...
TEMPERATURES SHOULD MODERATE BY LATE ON SUNDAY WITH HIGHS 40S
VALLEYS AND SOME 30S HIGHEST ELEVATIONS.
ONE OF THE MORE TRICKY PARTS OF THE EXTENDED FORECAST IS THE LOW
TEMPERATURE FORECAST ON MONDAY MORNING. THERE WILL LIKELY STILL BE
SIGNIFICANT SNOW COVER ACROSS THE AREA. IF WE CAN DECOUPLE THE
BOUNDARY LAYER FROM THE GRADIENT WIND FLOW...WITH CLEARING SKIES
TOWARD DAYBREAK...TEMPERATURES MAY FALL A GOOD TEN TO FIFTEEN
DEGREES BELOW FREEZING. FOR NOW WENT WITH LOWS AROUND FREEZING AND
THIS WILL LIKELY BE ADJUSTED AS WE GET LATER IN THE WEEKEND. A COLD
FRONT WILL CROSS THE AREA LATER MONDAY...BUT TEMPERATURES SHOULD
ONCE AGAIN REACH THE 40S IN THE VALLEYS BEFORE THE FRONT MOVES
THROUGH. A LITTLE COOLER IN THE HILLS WITH UPPER 30S FOR HIGHS.
TUESDAY LOOKS GENERALLY FAIR AND COLD BEHIND THE COLD FRONT. LOWS IN
THE TEENS AND TWENTIES AND HIGHS IN THE 20S AND 30S.
BY WEDNESDAY THE NEXT WARM FRONT IS SURGING TOWARDS THE AREA. THERE
MAY BE A BURST OF WARM ADVECTION PRECIPITATION AROUND DAYBREAK
WEDNESDAY MORNING. THIS COULD BE A MIXED BAG OF PRECIP TYPES. THE
REST OF THE DAY LOOKS CLOUDY WITH MODERATING TEMPERATURES AND
ANOTHER COLD FRONT APPROACHING QUICKLY FROM THE WEST. AS THIS COLD
FRONT MOVES THROUGH WEDNESDAY NIGHT...THERE MAY BE SOME RAIN SHOWERS
CHANGING TO SNOW SHOWERS. ANOTHER SHOT OF COLD AIR BEHIND THE FRONT
FOR THURSDAY AND FRIDAY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
MVFR CONDITIONS ARE OCCURRING ACROSS MOST OF THE ALBANY FORECAST
AREA THIS MORNING. THE EXCEPTION IS KPOU WHICH IS CURRENTLY VFR
BUT HAS BEEN BOUNCING BETWEEN VFR AND IFR DUE TO FOG. A BRIEF
PERIOD OF VFR IS EXPECTED AT THE TAF SITES THIS MORNING BEFORE A
VIGOROUS COLD UPPER LEVEL TROUGH BRINGS ANOTHER CHANCE FOR SNOW
LATER TODAY TO THE AREA WITH MVFR CONDITIONS EXPECTED AT ALL THE
TAF SITES BY LATER THIS AFTERNOON OR THIS EVENING. A LIGHT
ACCUMULATING SNOW IS AGAIN POSSIBLE WITH THIS SYSTEM. IMPROVEMENT
TO VFR CONDITIONS EXPECTED BY MID MORNING FRIDAY.
WINDS WILL BE NORTHWESTERLY AT LESS THAN 10 KTS THROUGH FRIDAY.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...FZRA.
SUNDAY NIGHT: SLIGHT CHANCE OF SHRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SLEET.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THROUGH THE
WEEKEND.
ADDITIONAL LIGHT PRECIPITATION AMOUNTS ARE EXPECTED WITH BASIN
AVERAGES AT A TENTH OF AN INCH OR LESS EXPECTED.
MILDER TEMPS ARE POSSIBLE SUNDAY WITH SOME SNOW MELT. HOWEVER...
TEMPERATURES ARE EXPECTED TO COOL OFF QUICKLY DURING MONDAY WITH
THE PASSAGE OF A STRONG COLD FRONT.
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.
&&
.CLIMATE...
A RECORD SNOWFALL OF 9.6 INCHES WAS SET AT ALBANY NY YESTERDAY.
THIS BREAKS THE OLD RECORD OF 4.9 SET IN 1888. ALSO...THIS PLACES
THE STORM INTO ONE OF THE TOP 10 SNOWSTORMS FOR NOVEMBER FOR ALBANY.
WITH ADDITIONAL SNOWFALL EXPECTED THIS WEEKEND...WE WILL ALSO WATCH HOW
MUCH ADDS UP TO SEE WHERE WE FINISH UP FOR SNOW BY THE END OF THE
MONTH.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM/WASULA
LONG TERM...SND
AVIATION...SND
HYDROLOGY...KL/BGM/WASULA
CLIMATE...ALY
AREA FORECAST DISCUSSION
NWS ALBANY NY
635 AM EST THU NOV 27 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL BRING SOME SCATTERED SNOW SHOWERS
TO REGION TODAY INTO TONIGHT. HIGH PRESSURE WILL RIDGE IN BRIEFLY
FOR FRIDAY WITH BELOW NORMAL TEMPERATURES. MILDER AIR ATTEMPTS TO
BUILD INTO THE REGION THIS WEEKEND...HOWEVER...IT WILL BE
ACCOMPANIED BY CLOUD COVER AND THE CHANCE FOR LIGHT SNOW OR RAIN
SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM EST...RADAR RETURNS ARE INCREASING UPSTREAM AS THAT
SHORT WAVE APPROACHES. IR SATELLITE IMAGERY SUPPORTS COOLING CLOUD
TOPS WITH THE EXPECTATIONS OF MORE SNOW DEVELOPING ACROSS THE REGION
TODAY. DID RAISE DEWPOINTS A FEW DEGREES BASED ON OBSERVATIONS AND
TEMPERATURES WILL LIKELY RISE EVER SO SLIGHTLY THROUGH THE DAY.
PREV DISC...
THE NOR`EASTER THAT PRODUCED A SIGNIFICANT SNOWFALL FOR THE REGION
WAS QUICKLY DEPARTING OFF THE COAST OF MAINE THIS MORNING /WAS
993MB AS OF 08Z/. DEFORMATION AXIS THAT MOVED ACROSS THE NORTHERN
2/3RDS OF THE REGION WAS TOO QUICKLY LIFTING NORTHEAST ACROSS NEW
ENGLAND AS SEEN IN THE COLDER IR SATELLITE IMAGERY CLOUD TOPS.
THROUGH THE NEXT FEW HOURS...WE CONTINUE TO WATCH THE POTENTIAL
MESOSCALE MOHAWK-HUDSON VALLEY CONVERGENCE AS METARS AND
STREAMLINE ANALYSIS POINT TOWARD WINDS CONVERGING INTO THE CAPITAL
REGION...HOWEVER...IT WAS ALSO FIGHTING SUBSIDENCE IN THE WAKE OF
THE NOR`EASTER. FOR NOW...WE WILL CONTINUE WITH CHC-SLIGHT CHC POPS
THROUGH THE EARLY MORNING HOURS.
H2O VAPOR LOOP DEPICTS A DEEP TROUGH ACROSS THE EASTERN 2/3RDS OF
NOAM. A COUPLE OF RATHER POTENT SHORT WAVES WERE OBSERVED...ONE
APPROACHING THE OHIO RIVER VALLEY AND THE OTHER TRACKING INTO THE
WESTERN GREAT LAKES. TEMPERATURES ALOFT WITH THESE FEATURES ARE
QUITE COLD WITH SUB -30C AIR AT H500 AND ABOVE. NCEP MODEL SUITE
AND INTERNATIONAL GUIDANCE ARE IN GOOD AGREEMENT WITH TRACKING
THESE WAVES ACROSS THE CWFA TODAY. QG FORCING WAS PRONOUNCED LATE
THIS MORNING INTO THE AFTERNOON HOURS ALONG WITH STEEPENING LAPSE
RATES THAT SHOULD RESULT WITH AN INCREASE IN SNOW SHOWER ACTIVITY
COVERAGE. 4KM SPC AND HRRR REFLECTIVITIES DO INDICATE AN INCREASE
IN COVERAGE OF SNOW SHOWERS AS WE WILL REFLECT THIS IN THE
GRIDS/FORECAST WITH RAISING POPS. MOST OF THE HIGHER POP VALUES
WILL BE INTO THE TERRAIN WITH OROGRAPHIC LIFTING. AS FOR
ADDITIONAL ACCUMULATIONS...WE COULD SEE AN ADDITIONAL INCH OR SO.
GUIDANCE TEMPERATURES ARE VERY CLOSE...HOWEVER...WITH FRESH SNOW
COVER WE WILL LEAN TOWARD A SLIGHTLY COOLER VALUES.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
RIDGING WILL BE BUILDING INTO THE REGION...HOWEVER...LAKE EFFECT
SNOW SHOWERS DOWNWIND OF LAKE ONTARIO WILL THE MAIN WEATHER ISSUE
ON FRIDAY. LATEST NAM12 SUGGESTS THE LOW LEVEL BOUNDARY LAYER
WINDS WILL INITIALLY BE NORTHWEST...BUT AS THE RIDGE
BUILDS...THOSE WINDS BE BACKING WITH TIME. THIS WOULD SUGGEST LAKE
EFFECT ACTIVITY THAT WILL BE WEST OF THE REGION INITIALLY TO
MIGRATE INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN
DACKS. DUE TO THE MIGRATORY NATURE...THE INLAND EXTENT IS EXPECTED
TO BE LIMITED AS WE WILL KEEP POPS INTO THE CHC-SCT CATEGORY.
OTHERWISE...THE REMAINDER OF THE REGION WILL BE RATHER TRANQUIL
WITH SOME PEAKS OF SUNSHINE. AS H850 TEMPS WILL RANGE BETWEEN -12C
TO -14C...IT WILL BE UNSEASONABLY COOL FOR LATE NOVEMBER.
FRIDAY NIGHT INTO SATURDAY...HIGH PRESSURE MOVES OFF THE ATLANTIC
SEABOARD AS STORM ATTEMPTS TO ORGANIZE ACROSS THE NORTHERN PLAINS
AND GREAT LAKES REGION. THIS WILL PLACE OUR REGION INTO A WARM
ADVECTION REGIME. ALTHOUGH...LOW LEVEL MOISTURE WILL REMAIN RATHER
HIGH TO KEEP CLOUDS IN THE FORECAST. AS FOR PRECIP
POTENTIAL...BROAD ISENTROPIC LIFT WILL BE UNDERWAY WITH THE BEST
LOWERING OF THE CPD/S TO BE NORTH AND WEST OF THE CWFA.
HOWEVER...SINCE THE LOW LEVELS WILL BECOME RATHER HIGH IN MOISTURE
CONTENT...WE WILL CONTINUE WITH THE CHC POPS OF LIGHT
PRECIPITATION THROUGH THE PERIOD. MOST OF THIS PRECIP SHOULD FALL
AS WINTER TYPE BUT SOME OF THE WARMER VALLEY LOCATIONS MAY
EXPERIENCE A MIX OF RAIN/SNOW SHOWERS.
GUIDANCE TEMPERATURES DIVERGE THROUGH THE SHORT TERM AND PER THE
CURRENT SNOW PACK...WE WILL LEAN TOWARD THE COOLER SIDE OF THE
GUIDANCE ENVELOPE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
LONG TERM PERIOD CHARACTERIZED BY CHANGEABLE WEATHER AND WIDELY
VARYING TEMPERATURES AS A SERIES OF FRONTS CROSS EASTERN NEW YORK
AND WESTERN NEW ENGLAND.
FOR SUNDAY...A WARM FRONT WILL BE CROSSING THE FORECAST AREA. FOR
NOW HAVE SLIGHT CHANCE POPS OVER MOST OF THE AREA WITH CHANCE POPS
OVER SOUTHWESTERN ADIRONDACKS AS BEST FORCING FOR ANY PRECIPITATION
MOVES NORTH OF THE AREA. AFTER A COLD THANKSGIVING WEEKEND...
TEMPERATURES SHOULD MODERATE BY LATE ON SUNDAY WITH HIGHS 40S
VALLEYS AND SOME 30S HIGHEST ELEVATIONS.
ONE OF THE MORE TRICKY PARTS OF THE EXTENDED FORECAST IS THE LOW
TEMPERATURE FORECAST ON MONDAY MORNING. THERE WILL LIKELY STILL BE
SIGNIFICANT SNOW COVER ACROSS THE AREA. IF WE CAN DECOUPLE THE
BOUNDARY LAYER FROM THE GRADIENT WIND FLOW...WITH CLEARING SKIES
TOWARD DAYBREAK...TEMPERATURES MAY FALL A GOOD TEN TO FIFTEEN
DEGREES BELOW FREEZING. FOR NOW WENT WITH LOWS AROUND FREEZING AND
THIS WILL LIKELY BE ADJUSTED AS WE GET LATER IN THE WEEKEND. A COLD
FRONT WILL CROSS THE AREA LATER MONDAY...BUT TEMPERATURES SHOULD
ONCE AGAIN REACH THE 40S IN THE VALLEYS BEFORE THE FRONT MOVES
THROUGH. A LITTLE COOLER IN THE HILLS WITH UPPER 30S FOR HIGHS.
TUESDAY LOOKS GENERALLY FAIR AND COLD BEHIND THE COLD FRONT. LOWS IN
THE TEENS AND TWENTIES AND HIGHS IN THE 20S AND 30S.
BY WEDNESDAY THE NEXT WARM FRONT IS SURGING TOWARDS THE AREA. THERE
MAY BE A BURST OF WARM ADVECTION PRECIPITATION AROUND DAYBREAK
WEDNESDAY MORNING. THIS COULD BE A MIXED BAG OF PRECIP TYPES. THE
REST OF THE DAY LOOKS CLOUDY WITH MODERATING TEMPERATURES AND
ANOTHER COLD FRONT APPROACHING QUICKLY FROM THE WEST. AS THIS COLD
FRONT MOVES THROUGH WEDNESDAY NIGHT...THERE MAY BE SOME RAIN SHOWERS
CHANGING TO SNOW SHOWERS. ANOTHER SHOT OF COLD AIR BEHIND THE FRONT
FOR THURSDAY AND FRIDAY.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
SNOW IS SLOWLY WINDING DOWN...BUT WILL CONTINUE FOR AT LEAST A
COUPLE OF MORE HOURS AT THE TAF SITES. BRIEF IMPROVEMENT TO VFR
CONDITIONS EXPECTED AFTER SUNRISE TODAY FOR THE VALLEY TAF
SITES...WITH CONTINUED MVFR AT KPSF. A VIGOROUS COLD UPPER LEVEL
TROUGH BRINGS ANOTHER CHANCE FOR SNOW LATER THANKSGIVING DAY TO
THE AREA WITH MVFR CONDITIONS EXPECTED AT ALL THE TAF SITES BY
SUNSET. A LIGHT ACCUMULATING SNOW IS AGAIN POSSIBLE LATER
THANKSGIVING DAY AND EVENING.
WINDS WILL BE NORTHWESTERLY TONIGHT AND DECREASE TO LESS THAN 10
KTS BY LATE TONIGHT...AND CONTINUE THROUGH THURSDAY.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...FZRA.
SUNDAY NIGHT: SLIGHT CHANCE OF SHRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SLEET.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THROUGH THE
WEEKEND.
ADDITIONAL LIGHT PRECIPITATION AMOUNTS ARE EXPECTED WITH BASIN
AVERAGES AT A TENTH OF AN INCH OR LESS EXPECTED.
MILDER TEMPS ARE POSSIBLE SUNDAY WITH SOME SNOW MELT. HOWEVER...
TEMPERATURES ARE EXPECTED TO COOL OFF QUICKLY DURING MONDAY WITH
THE PASSAGE OF A STRONG COLD FRONT.
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.
&&
.CLIMATE...
A RECORD SNOWFALL OF 9.6 INCHES WAS SET AT ALBANY NY YESTERDAY.
THIS BREAKS THE OLD RECORD OF 4.9 SET IN 1888. ALSO...THIS PLACES
ALBANY INTO ONE OF THE TOP 10 SNOWSTORMS FOR THE MONTH. WITH
ADDITIONAL SNOWFALL EXPECTED...WE WILL WATCH HOW MUCH ADDS UP TO
SEE WHERE WE FINISH UP BY THE END OF THE MONTH.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM/WASULA
LONG TERM...SND
AVIATION...SND/NAS
HYDROLOGY...KL/BGM/WASULA
CLIMATE...BGM/IAA
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1001 AM CST Thu Nov 27 2014
.UPDATE...
ISSUED AT 1000 AM CST THU NOV 27 2014
Have updated the forecast to significantly ramp up the PoP`s for
the next few hours from about Decatur northwest to Galesburg. An
area of light snow and flurries has been moving southeast out of
the Quad Cities. While significant accumulation is not
anticipated, the visibilities have been getting down to 1 to 2
miles at times which would imply more than just flurries, and
web cams around Peoria suggest a dusting of accumulation is
occurring in the heavier bands. The snow has been weakening as it
moves southeast through central Illinois, so have kept the
afternoon dry for now. Back edge of the cloud deck is along the
Illinois/Iowa border and slowly moving east, with the RAP guidance
continuing to indicate some gradual clearing from west to east
across our forecast area this afternoon.
&&
.SHORT TERM...(Today)
ISSUED AT 321 AM CST THU NOV 27 2014
08z/2am surface analysis shows clipper system tracking southeastward
through the Ohio River Valley, while high pressure builds into the
Northern Plains. Accumulating snow associated with the clipper has
ended, leaving behind mostly cloudy and cold conditions. Main
short-term forecast challenge will be timing the clearing trend
later today. Current IR satellite imagery shows clouds blanketing
the region, with the back edge evident across southeast Minnesota
into north-central Iowa. Based solely on satellite timing tools,
clearing would arrive in the Illinois River Valley between 15z
and 17z. However, with continued deep-layer northwesterly flow
and very cold air aloft, think clouds may tend to re-develop along
the back edge of the main cloud area, thus slowing the overall
eastward progression of the clearing. Negative Cu-rule values
support this theory, as does the latest HRRR. As a result, have
decided to go with an overcast morning across the board, followed
by a slow northwest to southeast clearing this afternoon. Some
locations along/east of I-57 will likely remain cloudy through the
entire day. Due to the cloud cover and gusty northwesterly winds,
high temperatures will remain in the 20s across most of the area,
with a few lower 30s south of I-70.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 321 AM CST THU NOV 27 2014
After chilly low temperatures in the teens tonight, a major
warming trend will get underway by the end of the week. High
pressure will shift east of the region on Friday, allowing gusty
southerly winds to develop. Despite partial sunshine and strong
WAA, warming trend will be mitigated by existing snow cover along
a Rushville...to Springfield...to Robinson line. Have therefore
lowered highs across this area by 3-4 degrees, with readings
reaching the lower 40s. Much warmer weather is expected
everywhere on Saturday as strong southerly flow continues. Models
are showing a fetch of increasing low-level moisture from the
western Gulf of Mexico northward into central Illinois, with
surface dew points increasing from the lower 30s early in the day
to well into the 40s to near 50 degrees late. Forecast soundings
are showing saturation below 850mb, which suggests increasing
low-level cloudiness. Have therefore gone with a mostly cloudy
forecast with high temperatures reaching the lower to middle 50s.
Another warm day is expected on Sunday, although an approaching
cold front may trigger scattered showers across the central and
southern zones as the day progresses. Front will drop into the Ohio
River Valley by Sunday night, with a colder air mass settling
southward early next week. Model discrepancies still exist Sunday
night, with the ECMWF trying to develop some light precip
along/north of the boundary into the colder air mass. Meanwhile, the
GFS keeps the light precip confined to areas along/south of the
front. With no clear upper wave to support the post-frontal precip,
have opted to side with the GFS here, resulting in dry weather
across all but the far SE CWA where a few rain showers may linger.
After that, major model differences arise by the middle of next week
as all are in poor agreement concerning the evolution of a closed
upper low over the central Pacific. 00z Nov 27 GFS shows this
feature shearing eastward across the central CONUS, eventually
triggering overrunning precip across Illinois by
Wednesday/Thursday. The ECMWF takes the low and gradually absorbs
it into a stronger low over the Gulf of Alaska, with a downstream
trough providing cool/dry weather to Illinois on
Wednesday/Thursday. Meanwhile, the GEM keeps the low off the coast
of California the entire time and also features a cool/dry forecast
for Illinois. With so much uncertainty, decided to make very few
changes to the going forecast beyond Monday. For now will maintain
dry weather through Wednesday with a gradual warming trend.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
ISSUED AT 557 AM CST THU NOV 27 2014
VFR conditions across the central Illinois terminals will quickly
degrade to MVFR this morning as a band of SC spreads in from the
northwest. Then, skies will scatter out this afternoon as a ridge
of high pressure begins to build into the area. However, mid/high
level VFR cigs will spread into the region tonight ahead of the
next weather disturbance. A period of 10-15 kt northwest winds
will exist to start the day, with a few gusts to 20 kts possible
into midday. Then, winds will trend light/variable as the ridge of
high pressure builds in for tonight.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Bak
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
651 AM EST THU NOV 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 556 AM EST THU NOV 27 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS REVEAL AN AMPLIFIED PATTERN
ACROSS NAMERICA WITH A RIDGE OVER THE W COAST AND A TROF EXTENDING
FROM NCNTRL CANADA INTO THE ERN CONUS. A SHORTWAVE TROF MOVING
ACROSS THE REGION IS PRODUCING SOME -SN OVER NCNTRL WI AND PERHAPS
PROVIDING SOME ENHANCEMENT TO LES OVER ERN LAKE SUPERIOR INTO THE
THE ERN HALF OF UPPER MI. COLD AND VERY DRY AIR MASS UPSTREAM AS
NOTED ON 00Z KINL SNDG AND MINUS TEENS TO MINUS 20S DEWPOINTS OVER
WRN ONTARIO AND NRN MN WILL NEGATIVELY IMPACT LES FROM WEST TO EAST
TODAY AS IT MOVES ACROSS LAKE SUPERIOR IN THE WAKE OF THE SHORTWAVE
PASSAGE.
TODAY...MODEL SNDGS SHOW SHARP LOWERING OF INVERSION BASES BLO 4KFT
AS Q-VECT DIV SPREADING FROM WEST TO EAST ACROSS THE FCST AREA TODAY
AHEAD OF ADVANCING SHORTWAVE RIDGE. LOW-LEVEL FLOW ALSO BCMS MORE
ANTICYCLONIC THROUGH THE DAY WHICH IN TURN WILL WEAKEN LOW-LVL
CONVERGENCE. ALL THESE FACTORS WILL COMBINE TO QUICKLY DIMINISH LES
FROM W TO E THRU THE DAY. IN FACT OVER THE FAR W...EXPECT LES TO END
LATE IN THE AFTN AROUND KIWD AS FLOW BACKS SW. THE ONE POSITIVE
FACTOR FOR THE LES S THAT THE DGZ IS FIRMLY SITUATED THROUGH THE
CONVECTIVE LAYER ALLOWING FOR FLUFFY SNOW ACCUMULATIONS.
SO...DESPITE THE NEGATIVES LEADING TO MOSTLY LIGHT LES ON THE
WHOLE...MIGHT BE ABLE TO STILL GET 3-4 INCHES OF ADDITIONAL SNOW
WHERE LES IS MOST PERSISTENT. THE GREATEST ACCUMULATIONS WILL OCCUR
E OF MARQUETTE WHERE LOW-LEVEL FLOW IS MORE CYCLONIC THRU THE EARLY
PART OF THE DAY AND WHERE NW FETCH MAY BE HELPED BY LAKE NIPIGON
PRECONDITIONING. AWAY FROM THE MAIN LES...SCT -SHSN/FLURRIES ARE
POSSIBLE AT TIMES...EXCEPT OVER THE FAR SCNTRL. TEMPS WILL BE
UNSEASONABLY COLD TODAY AS 850MB THERMAL TROF (AROUND -20C) PASSES
ACROSS THE AREA. EXPECT HIGHS RANGING FM 10 TO 15F OVER THE WEST
HALF...TO AROUND 20F ALONG LAKE SUPERIOR AND E. RECORD LOW MAX
TEMP OF 18F HERE AT NWS MQT WILL FALL. IF TEMP DOESN`T REACH
14F...IT WILL BE THE COLDEST MAX TEMP FOR SO EARLY IN THE SEASON.
TONIGHT...THE LINGERING LES WILL DIMINISH OVER THE KEWEENAW AND FAR
ERN SHORELINE PORTION OF CWA AS THE SFC RIDGE AXIS SLIDES THROUGH
THE AREA ALLOWING THE LOW LEVEL WINDS TO BACK SW. WITH LIGHT
WINDS AND A PERIOD OF CLEARING OVER THE INTERIOR WEST DURING THE
EVENING...TEMPS WILL DROP QUICKLY TO MINS ON THE LOWER END OF MODEL
GUIDANCE BEFORE RECOVERING OVERNIGHT AS CLOUDS MOVE IN. MODELS
TRENDING A BIT SLOWER WITH ARRIVAL OF LIGHT SNOW INTO THE WEST LATE
WITH THE DEVELOPING WAA PATTERN...SO HAVE TRIMMED BACK POPS TO
SLIGHT CHC.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 509 AM EST THU NOV 27 2014
TROUGHING BRINGING THE WELL BLO NORMAL TEMPERATURES ACROSS THE AREA
TODAY EXITS OVER EASTERN CANADA AND NEW ENGLAND ON FRIDAY. UPPER
LEVEL FLOW BECOMES MORE PROGRESSIVE FROM THE PACIFIC NW ACROSS THE
NORTHERN PLAINS AND OVER THE GREAT LAKES REGION. SHORTWAVE TROUGH
CURRENTLY JUST OFFSHORE OF PACIFIC NW HEADS EAST AND WILL SUPPORT
AREA OF WARM ADVECTION/ISENTROPIC ASCENT ALONG TIGHT BAROCLINIC ZONE
SFC-H85. MODELS STILL DIFFER ON WHERE SHARPEST TEMPERATURE GRADIENT
SETS UP...BUT SEEMS THAT AT LEAST THE SOUTH HALF OF UPR MICHIGAN
SEES WIDESPREAD SNOW...WITH A BIT MORE QUESTION ON NORTHERN EXTENT.
IF BAND OF MORE CONCENTRATED SNOW SLIDES NORTHWARD THEN COULD SEE
AMOUNTS NEARING ADVY ALONG THE WI BORDER AND NEAR BAY OF GREEN BAY
FRIDAY AFTN INTO FRIDAY EVENING. PRIMARY AREA OF CONCERN STILL IS OVER
EASTERN CWA THOUGH...SCHOOLCRAFT AND LUCE COUNTIES...DUE TO LAKE
ENHANCEMENT OFF LK MICHIGAN AS THE LARGER SCALE MOISTURE AND FORCING
WITH THE SHORTWAVE COMBINES WITH MEAN BLRY SSW FLOW AND H85 TEMPS
LOWER THAN -10C...PLENTY LOW ENOUGH FOR LAKE ENHANCEMENT WITH LK
MICHIGAN WATER TEMPS AROUND UP TO 4C. IF THE FARTHER NORTH NAM IDEA
IS CORRECT WITH MORE DIRECT INFLUENCE FROM THE INCOMING SYSTEM...THEN
MODERATE TO HEAVY SNOW WOULD OCCUR. BLEND OF OTHER MODELS...INCLUDING
THE FAVORED ECMWF/GEM-NH...POINT TO SOLID ADVY AMOUNTS. WILL MENTION
IN THE HWO AND HIGHLIGHT IN EHWO GRAPHICS...BUT NOT ISSUE ANY WATCH
ATTM GIVEN THE UNCERTAINTY ON TRACK OF INCOMING SYSTEM.
MESSY FORECAST LATER FRIDAY NIGHT INTO SATURDAY. OR MAYBE IT WILL
JUST END UP BENIGN. STILL TRYING TO FIGURE THIS OUT...BUT ECMWF/GEM
AND TREND FROM GFS WOULD SUGGEST MORE DRIER IDEA. ECMWF AND GEM ARE
FARTHER NORTH WITH LARGER SCALE Q-VECTOR CONVERGENCE AND DEEP
MOISTURE TIED INTO THE NEXT SHORTWAVE/SFC LOW MOVING ACROSS IN WHAT
LOOKS MORE LIKE A ZONAL FLOW PATTERN. H85 TEMPS QUITE WARM OFF THE
ECMWF WITH +8C...YES PLUS 8...INTO SCNTRL UPR MICHIGAN BY 00Z
SUNDAY. GEM EVEN WARMER AND THE NAM/GFS IN THE BALLPARK AS WELL.
EVEN WITH THE WARMTH...SOUNDINGS FM THE NAM/GFS SUGGEST THE ONLY
KIND OF PRECIP OCCURRING...IF ANY...WOULD BE DRIZZLE AS ONLY MOISTURE
IS BLO H85 WITH DRY AIR ALOFT. EXCEPTION TO THIS WOULD BE OVER THE
NORTH AND EAST CWA SATURDAY MORNING AND THEN RETURNING TO THE
NORTHWEST CWA LATER SATURDAY NIGHT ONCE THE SFC LOW PASSES BY AND A
COLD FRONT RE-ENTERS THE PICTURE. HAVE TRENDED TOWARD THE DZ/FZDZ
IDEA FOR LATE FRIDAY NIGHT THROUGH SATURDAY. NOW IF THIS FORECAST OF
LOW LEVEL MOISTURE TRAPPED BENEATH THE WARM AIR ADVECTION ALOFT TURNS
OUT TO BE OVERDONE AS HAS OCCURRED IN THE PAST...THEN SATURDAY COULD
ACTUALLY END UP BEING AN NICE DAY WITH PARTLY SUNNY SKIES AND ABOVE
NORMAL TEMPS. MIXING TO H9 VALUES OFF THE GFS WOULD YIELD LOW 40S
OVER PARTS OF THE AREA. FOR NOW...KEPT WITH THE LOW CLOUD/DZ IDEA AND
HAVE HIGHS IN THE MID 30S.
ONCE THE COLD FRONT ARRIVES LATER SATURDAY NIGHT...PRETTY QUICK DROP
OFF IN TEMPS AT H85. ECMWF SLOWER THAN THE GFS AND PROBABLY IS MORE
ON TRACK GIVEN THE FARTHER NORTH TREND OF WARMER AIR TO START THE
WEEKEND. EVEN SO...ENOUGH COLD AIR BY SUNDAY AFTN TO START THE LAKE
EFFECT UP AGAIN FOR AREAS FAVORED BY NORTHWEST WINDS. SHORTWAVE MOVING
THROUGH SUNDAY INTO MONDAY COULD RESULT IN A PERIOD OR TWO OF LAKE
ENHANCEMENT. CORE OF COLDEST AIR ARRIVES ON MONDAY. H85 TEMPS A VERY
CHILLY -20C TO -24C...COLDEST ON THE GFS. AT LEAST LIGHT LES SHOULD
CONTINUE NEAR LK SUPERIOR AND EAST. CENTER OF HIGH PRESSURE RIDGE IS
MORE OVER THE PLAINS...SO PRESSURE GRADIENT WILL BE FAIRLY TIGHT
LEADING TO SOME LOWER WIND CHILLS ON MONDAY MORNING.
ONCE THE HIGH MOVES TOWARD THE LOWER GREAT LAKES ON TUESDAY...TEMPS
MODERATE IN WARM AIR ADVECTION ON THE BACK SIDE OF THE HIGH. COULD
BE SOME SNOW BREAK OUT OVER REGION DUE TO THE WARM AND MOIST ADVECTION.
BEST CHANCE OF THAT LOOKS TO BE NEXT TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 645 AM EST THU NOV 27 2014
WITH INCREASING SUBSIDENCE/DRY ADVECTION IN ADVANCE OF HI PRES
MOVING E FM THE NRN PLAINS...EXPECT GRADUALLY IMPROVING CONDITIONS
TODAY AT TAF SITES. WITH THE MOST FAVORABLE UPSLOPE/CONFLUENT N
WIND...IWD WL SEE A LONGER PERSISTENCE OF SHSN/IFR VSBYS THIS MORNING.
AS THE HI AND ACCOMPANYING DRIER AIR EDGE CLOSER...THE LLVL WINDS WL
BACK TOWARD THE WNW EARLY THIS AFTN AND THEN TO THE WSW THIS EVNG...
RESULTING IN A RETURN TO VFR CONDITIONS AT IWD. MORE UPSLOPE WRLY WIND
AT CMX BY THIS AFTERNOON MAY HOLD CIGS IN THE MVFR RANGE AT THAT
LOCATION THRU THE MUCH OF THIS EVENING. NW WINDS BACKING TO S-SW
TONIGHT AT KSAW SHOULD CONTINUE THE VFR CONDITIONS THERE THRU THE
PERIOD. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 556 AM EST THU NOV 27 2014
NW WINDS TO 25 KNOTS WILL DIMINISH TO UNDER 20 KT W TO E TODAY INTO
TONIGHT AS HIGH PRES RIDGE ARRIVES. WITH ANOTHER COLD FRONT
PUSHING ACROSS THE UPPER LAKES SAT NIGHT...EXPECT INCREASING S/SW
WINDS TO 15-25KT FRI BEHIND THE FRONT...NW WINDS MAY REACH 20-30KT
LATE SAT NIGHT AND SUN AND INCREASE TO GALES BY SUN NIGHT INTO MON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
557 AM EST THU NOV 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 556 AM EST THU NOV 27 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS REVEAL AN AMPLIFIED PATTERN
ACROSS NAMERICA WITH A RIDGE OVER THE W COAST AND A TROF EXTENDING
FROM NCNTRL CANADA INTO THE ERN CONUS. A SHORTWAVE TROF MOVING
ACROSS THE REGION IS PRODUCING SOME -SN OVER NCNTRL WI AND PERHAPS
PROVIDING SOME ENHANCEMENT TO LES OVER ERN LAKE SUPERIOR INTO THE
THE ERN HALF OF UPPER MI. COLD AND VERY DRY AIR MASS UPSTREAM AS
NOTED ON 00Z KINL SNDG AND MINUS TEENS TO MINUS 20S DEWPOINTS OVER
WRN ONTARIO AND NRN MN WILL NEGATIVELY IMPACT LES FROM WEST TO EAST
TODAY AS IT MOVES ACROSS LAKE SUPERIOR IN THE WAKE OF THE SHORTWAVE
PASSAGE.
TODAY...MODEL SNDGS SHOW SHARP LOWERING OF INVERSION BASES BLO 4KFT
AS Q-VECT DIV SPREADING FROM WEST TO EAST ACROSS THE FCST AREA TODAY
AHEAD OF ADVANCING SHORTWAVE RIDGE. LOW-LEVEL FLOW ALSO BCMS MORE
ANTICYCLONIC THROUGH THE DAY WHICH IN TURN WILL WEAKEN LOW-LVL
CONVERGENCE. ALL THESE FACTORS WILL COMBINE TO QUICKLY DIMINISH LES
FROM W TO E THRU THE DAY. IN FACT OVER THE FAR W...EXPECT LES TO END
LATE IN THE AFTN AROUND KIWD AS FLOW BACKS SW. THE ONE POSITIVE
FACTOR FOR THE LES S THAT THE DGZ IS FIRMLY SITUATED THROUGH THE
CONVECTIVE LAYER ALLOWING FOR FLUFFY SNOW ACCUMULATIONS.
SO...DESPITE THE NEGATIVES LEADING TO MOSTLY LIGHT LES ON THE
WHOLE...MIGHT BE ABLE TO STILL GET 3-4 INCHES OF ADDITIONAL SNOW
WHERE LES IS MOST PERSISTENT. THE GREATEST ACCUMULATIONS WILL OCCUR
E OF MARQUETTE WHERE LOW-LEVEL FLOW IS MORE CYCLONIC THRU THE EARLY
PART OF THE DAY AND WHERE NW FETCH MAY BE HELPED BY LAKE NIPIGON
PRECONDITIONING. AWAY FROM THE MAIN LES...SCT -SHSN/FLURRIES ARE
POSSIBLE AT TIMES...EXCEPT OVER THE FAR SCNTRL. TEMPS WILL BE
UNSEASONABLY COLD TODAY AS 850MB THERMAL TROF (AROUND -20C) PASSES
ACROSS THE AREA. EXPECT HIGHS RANGING FM 10 TO 15F OVER THE WEST
HALF...TO AROUND 20F ALONG LAKE SUPERIOR AND E. RECORD LOW MAX
TEMP OF 18F HERE AT NWS MQT WILL FALL. IF TEMP DOESN`T REACH
14F...IT WILL BE THE COLDEST MAX TEMP FOR SO EARLY IN THE SEASON.
TONIGHT...THE LINGERING LES WILL DIMINISH OVER THE KEWEENAW AND FAR
ERN SHORELINE PORTION OF CWA AS THE SFC RIDGE AXIS SLIDES THROUGH
THE AREA ALLOWING THE LOW LEVEL WINDS TO BACK SW. WITH LIGHT
WINDS AND A PERIOD OF CLEARING OVER THE INTERIOR WEST DURING THE
EVENING...TEMPS WILL DROP QUICKLY TO MINS ON THE LOWER END OF MODEL
GUIDANCE BEFORE RECOVERING OVERNIGHT AS CLOUDS MOVE IN. MODELS
TRENDING A BIT SLOWER WITH ARRIVAL OF LIGHT SNOW INTO THE WEST LATE
WITH THE DEVELOPING WAA PATTERN...SO HAVE TRIMMED BACK POPS TO
SLIGHT CHC.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 509 AM EST THU NOV 27 2014
TROUGHING BRINGING THE WELL BLO NORMAL TEMPERATURES ACROSS THE AREA
TODAY EXITS OVER EASTERN CANADA AND NEW ENGLAND ON FRIDAY. UPPER
LEVEL FLOW BECOMES MORE PROGRESSIVE FROM THE PACIFIC NW ACROSS THE
NORTHERN PLAINS AND OVER THE GREAT LAKES REGION. SHORTWAVE TROUGH
CURRENTLY JUST OFFSHORE OF PACIFIC NW HEADS EAST AND WILL SUPPORT
AREA OF WARM ADVECTION/ISENTROPIC ASCENT ALONG TIGHT BAROCLINIC ZONE
SFC-H85. MODELS STILL DIFFER ON WHERE SHARPEST TEMPERATURE GRADIENT
SETS UP...BUT SEEMS THAT AT LEAST THE SOUTH HALF OF UPR MICHIGAN
SEES WIDESPREAD SNOW...WITH A BIT MORE QUESTION ON NORTHERN EXTENT.
IF BAND OF MORE CONCENTRATED SNOW SLIDES NORTHWARD THEN COULD SEE
AMOUNTS NEARING ADVY ALONG THE WI BORDER AND NEAR BAY OF GREEN BAY
FRIDAY AFTN INTO FRIDAY EVENING. PRIMARY AREA OF CONCERN STILL IS OVER
EASTERN CWA THOUGH...SCHOOLCRAFT AND LUCE COUNTIES...DUE TO LAKE
ENHANCEMENT OFF LK MICHIGAN AS THE LARGER SCALE MOISTURE AND FORCING
WITH THE SHORTWAVE COMBINES WITH MEAN BLRY SSW FLOW AND H85 TEMPS
LOWER THAN -10C...PLENTY LOW ENOUGH FOR LAKE ENHANCEMENT WITH LK
MICHIGAN WATER TEMPS AROUND UP TO 4C. IF THE FARTHER NORTH NAM IDEA
IS CORRECT WITH MORE DIRECT INFLUENCE FROM THE INCOMING SYSTEM...THEN
MODERATE TO HEAVY SNOW WOULD OCCUR. BLEND OF OTHER MODELS...INCLUDING
THE FAVORED ECMWF/GEM-NH...POINT TO SOLID ADVY AMOUNTS. WILL MENTION
IN THE HWO AND HIGHLIGHT IN EHWO GRAPHICS...BUT NOT ISSUE ANY WATCH
ATTM GIVEN THE UNCERTAINTY ON TRACK OF INCOMING SYSTEM.
MESSY FORECAST LATER FRIDAY NIGHT INTO SATURDAY. OR MAYBE IT WILL
JUST END UP BENIGN. STILL TRYING TO FIGURE THIS OUT...BUT ECMWF/GEM
AND TREND FROM GFS WOULD SUGGEST MORE DRIER IDEA. ECMWF AND GEM ARE
FARTHER NORTH WITH LARGER SCALE Q-VECTOR CONVERGENCE AND DEEP
MOISTURE TIED INTO THE NEXT SHORTWAVE/SFC LOW MOVING ACROSS IN WHAT
LOOKS MORE LIKE A ZONAL FLOW PATTERN. H85 TEMPS QUITE WARM OFF THE
ECMWF WITH +8C...YES PLUS 8...INTO SCNTRL UPR MICHIGAN BY 00Z
SUNDAY. GEM EVEN WARMER AND THE NAM/GFS IN THE BALLPARK AS WELL.
EVEN WITH THE WARMTH...SOUNDINGS FM THE NAM/GFS SUGGEST THE ONLY
KIND OF PRECIP OCCURRING...IF ANY...WOULD BE DRIZZLE AS ONLY MOISTURE
IS BLO H85 WITH DRY AIR ALOFT. EXCEPTION TO THIS WOULD BE OVER THE
NORTH AND EAST CWA SATURDAY MORNING AND THEN RETURNING TO THE
NORTHWEST CWA LATER SATURDAY NIGHT ONCE THE SFC LOW PASSES BY AND A
COLD FRONT RE-ENTERS THE PICTURE. HAVE TRENDED TOWARD THE DZ/FZDZ
IDEA FOR LATE FRIDAY NIGHT THROUGH SATURDAY. NOW IF THIS FORECAST OF
LOW LEVEL MOISTURE TRAPPED BENEATH THE WARM AIR ADVECTION ALOFT TURNS
OUT TO BE OVERDONE AS HAS OCCURRED IN THE PAST...THEN SATURDAY COULD
ACTUALLY END UP BEING AN NICE DAY WITH PARTLY SUNNY SKIES AND ABOVE
NORMAL TEMPS. MIXING TO H9 VALUES OFF THE GFS WOULD YIELD LOW 40S
OVER PARTS OF THE AREA. FOR NOW...KEPT WITH THE LOW CLOUD/DZ IDEA AND
HAVE HIGHS IN THE MID 30S.
ONCE THE COLD FRONT ARRIVES LATER SATURDAY NIGHT...PRETTY QUICK DROP
OFF IN TEMPS AT H85. ECMWF SLOWER THAN THE GFS AND PROBABLY IS MORE
ON TRACK GIVEN THE FARTHER NORTH TREND OF WARMER AIR TO START THE
WEEKEND. EVEN SO...ENOUGH COLD AIR BY SUNDAY AFTN TO START THE LAKE
EFFECT UP AGAIN FOR AREAS FAVORED BY NORTHWEST WINDS. SHORTWAVE MOVING
THROUGH SUNDAY INTO MONDAY COULD RESULT IN A PERIOD OR TWO OF LAKE
ENHANCEMENT. CORE OF COLDEST AIR ARRIVES ON MONDAY. H85 TEMPS A VERY
CHILLY -20C TO -24C...COLDEST ON THE GFS. AT LEAST LIGHT LES SHOULD
CONTINUE NEAR LK SUPERIOR AND EAST. CENTER OF HIGH PRESSURE RIDGE IS
MORE OVER THE PLAINS...SO PRESSURE GRADIENT WILL BE FAIRLY TIGHT
LEADING TO SOME LOWER WIND CHILLS ON MONDAY MORNING.
ONCE THE HIGH MOVES TOWARD THE LOWER GREAT LAKES ON TUESDAY...TEMPS
MODERATE IN WARM AIR ADVECTION ON THE BACK SIDE OF THE HIGH. COULD
BE SOME SNOW BREAK OUT OVER REGION DUE TO THE WARM AND MOIST ADVECTION.
BEST CHANCE OF THAT LOOKS TO BE NEXT TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 126 AM EST THU NOV 27 2014
WITH INCREASING SUBSIDENCE/DRY ADVECTION IN ADVANCE OF HI PRES
MOVING E FM THE NRN PLAINS...EXPECT GRADUALLY IMPROVING CONDITIONS
AT THE TAF SITES FM IFR IN THE FIRST COUPLE HRS TO PREDOMINANT MVFR.
WITH THE MOST FAVORABLE UPSLOPE/CONFLUENT N WIND...IWD WL SEE A
LONGER PERSISTENCE OF SHSN/IFR VSBYS. AS THE HI AND ACCOMPANYING
DRIER AIR EDGE CLOSER ON THANKSGIVING...THE LLVL WINDS WL BACK
TOWARD THE W BY LATE THIS AFTN AND THEN TO THE WSW THIS EVNG...
RESULTING IN A RETURN TO VFR CONDITIONS IN THE AFTN AT IWD AND SAW.
BUT MORE UPSLOPE WIND AT CMX MAY HOLD CIGS IN THE MVFR RANGE AT THAT
LOCATION THRU THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 556 AM EST THU NOV 27 2014
NW WINDS TO 25 KNOTS WILL DIMINISH TO UNDER 20 KT W TO E TODAY INTO
TONIGHT AS HIGH PRES RIDGE ARRIVES. WITH ANOTHER COLD FRONT
PUSHING ACROSS THE UPPER LAKES SAT NIGHT...EXPECT INCREASING S/SW
WINDS TO 15-25KT FRI BEHIND THE FRONT...NW WINDS MAY REACH 20-30KT
LATE SAT NIGHT AND SUN AND INCREASE TO GALES BY SUN NIGHT INTO MON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...KC
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
528 AM EST THU NOV 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 528 AM EST THU NOV 27 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS REVEAL AN AMPLIFIED PATTERN
ACROSS NAMERICA WITH A RIDGE OVER THE W COAST AND A TROF EXTENDING
FROM NCNTRL CANADA INTO THE ERN CONUS. A SHORTWAVE TROF MOVING
ACROSS THE REGION IS PRODUCING SOME -SN OVER NCNTRL WI AND PERHAPS
PROVIDING SOME ENHANCEMENT TO LES OVER ERN LAKE SUPERIOR INTO THE
THE ERN HALF OF UPPER MI. COLD AND VERY DRY AIR MASS UPSTREAM AS
NOTED ON 00Z KINL SNDG AND MINUS TEENS TO MINUS 20S DEWPOINTS OVER
WRN ONTARIO AND NRN MN WILL NEGATIVELY IMPACT LES FROM WEST TO EAST
TODAY AS IT MOVES ACROSS LAKE SUPERIOR IN THE WAKE OF THE SHORTWAVE
PASSAGE.
TODAY...MODEL SNDGS SHOW SHARP LOWERING OF INVERSION BASES BLO 4KFT
AS Q-VECT DIV SPREADING FROM WEST TO EAST ACROSS THE FCST AREA TODAY
AHEAD OF ADVANCING SHORTWAVE RIDGE. LOW-LEVEL FLOW ALSO BCMS MORE
ANTICYCLONIC THROUGH THE DAY WHICH IN TURN WILL WEAKEN LOW-LVL
CONVERGENCE. ALL THESE FACTORS WILL COMBINE TO QUICKLY DIMINISH LES
FROM W TO E THRU THE DAY. IN FACT OVER THE FAR W...EXPECT LES TO END
LATE IN THE AFTN AROUND KIWD AS FLOW BACKS SW. THE ONE POSITIVE
FACTOR FOR THE LES S THAT THE DGZ IS FIRMLY SITUATED THROUGH THE
CONVECTIVE LAYER ALLOWING FOR FLUFFY SNOW ACCUMULATIONS.
SO...DESPITE THE NEGATIVES LEADING TO MOSTLY LIGHT LES ON THE
WHOLE...MIGHT BE ABLE TO STILL GET 3-4 INCHES OF ADDITIONAL SNOW
WHERE LES IS MOST PERSISTENT. THE GREATEST ACCUMULATIONS WILL OCCUR
E OF MARQUETTE WHERE LOW-LEVEL FLOW IS MORE CYCLONIC THRU THE EARLY
PART OF THE DAY AND WHERE NW FETCH MAY BE HELPED BY LAKE NIPIGON
PRECONDITIONING. AWAY FROM THE MAIN LES...SCT -SHSN/FLURRIES ARE
POSSIBLE AT TIMES...EXCEPT OVER THE FAR SCNTRL. TEMPS WILL BE
UNSEASONABLY COLD TODAY AS 850MB THERMAL TROF (AROUND -20C) PASSES
ACROSS THE AREA. EXPECT HIGHS RANGING FM 10 TO 15F OVER THE WEST
HALF...TO AROUND 20F ALONG LAKE SUPERIOR AND E. RECORD LOW MAX
TEMP OF 18F HERE AT NWS MQT WILL FALL. IF TEMP DOESN`T REACH
14F...IT WILL BE THE COLDEST MAX TEMP FOR SO EARLY IN THE SEASON.
TONIGHT...THE LINGERING LES WILL DIMINISH OVER THE KEWEENAW AND FAR
ERN SHORELINE PORTION OF CWA AS THE SFC RIDGE AXIS SLIDES THROUGH
THE AREA ALLOWING THE LOW LEVEL WINDS TO BACK SW. WITH LIGHT
WINDS AND A PERIOD OF CLEARING OVER THE INTERIOR WEST DURING THE
EVENING...TEMPS WILL DROP QUICKLY TO MINS ON THE LOWER END OF MODEL
GUIDANCE BEFORE RECOVERING OVERNIGHT AS CLOUDS MOVE IN. MODELS
TRENDING A BIT SLOWER WITH ARRIVAL OF LIGHT SNOW INTO THE WEST LATE
WITH THE DEVELOPING WAA PATTERN...SO HAVE TRIMMED BACK POPS TO
SLIGHT CHC.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 509 AM EST THU NOV 27 2014
TROUGHING BRINGING THE WELL BLO NORMAL TEMPERATURES ACROSS THE AREA
TODAY EXITS OVER EASTERN CANADA AND NEW ENGLAND ON FRIDAY. UPPER
LEVEL FLOW BECOMES MORE PROGRESSIVE FROM THE PACIFIC NW ACROSS THE
NORTHERN PLAINS AND OVER THE GREAT LAKES REGION. SHORTWAVE TROUGH
CURRENTLY JUST OFFSHORE OF PACIFIC NW HEADS EAST AND WILL SUPPORT
AREA OF WARM ADVECTION/ISENTROPIC ASCENT ALONG TIGHT BAROCLINIC ZONE
SFC-H85. MODELS STILL DIFFER ON WHERE SHARPEST TEMPERATURE GRADIENT
SETS UP...BUT SEEMS THAT AT LEAST THE SOUTH HALF OF UPR MICHIGAN
SEES WIDESPREAD SNOW...WITH A BIT MORE QUESTION ON NORTHERN EXTENT.
IF BAND OF MORE CONCENTRATED SNOW SLIDES NORTHWARD THEN COULD SEE
AMOUNTS NEARING ADVY ALONG THE WI BORDER AND NEAR BAY OF GREEN BAY
FRIDAY AFTN INTO FRIDAY EVENING. PRIMARY AREA OF CONCERN STILL IS OVER
EASTERN CWA THOUGH...SCHOOLCRAFT AND LUCE COUNTIES...DUE TO LAKE
ENHANCEMENT OFF LK MICHIGAN AS THE LARGER SCALE MOISTURE AND FORCING
WITH THE SHORTWAVE COMBINES WITH MEAN BLRY SSW FLOW AND H85 TEMPS
LOWER THAN -10C...PLENTY LOW ENOUGH FOR LAKE ENHANCEMENT WITH LK
MICHIGAN WATER TEMPS AROUND UP TO 4C. IF THE FARTHER NORTH NAM IDEA
IS CORRECT WITH MORE DIRECT INFLUENCE FROM THE INCOMING SYSTEM...THEN
MODERATE TO HEAVY SNOW WOULD OCCUR. BLEND OF OTHER MODELS...INCLUDING
THE FAVORED ECMWF/GEM-NH...POINT TO SOLID ADVY AMOUNTS. WILL MENTION
IN THE HWO AND HIGHLIGHT IN EHWO GRAPHICS...BUT NOT ISSUE ANY WATCH
ATTM GIVEN THE UNCERTAINTY ON TRACK OF INCOMING SYSTEM.
MESSY FORECAST LATER FRIDAY NIGHT INTO SATURDAY. OR MAYBE IT WILL
JUST END UP BENIGN. STILL TRYING TO FIGURE THIS OUT...BUT ECMWF/GEM
AND TREND FROM GFS WOULD SUGGEST MORE DRIER IDEA. ECMWF AND GEM ARE
FARTHER NORTH WITH LARGER SCALE Q-VECTOR CONVERGENCE AND DEEP
MOISTURE TIED INTO THE NEXT SHORTWAVE/SFC LOW MOVING ACROSS IN WHAT
LOOKS MORE LIKE A ZONAL FLOW PATTERN. H85 TEMPS QUITE WARM OFF THE
ECMWF WITH +8C...YES PLUS 8...INTO SCNTRL UPR MICHIGAN BY 00Z
SUNDAY. GEM EVEN WARMER AND THE NAM/GFS IN THE BALLPARK AS WELL.
EVEN WITH THE WARMTH...SOUNDINGS FM THE NAM/GFS SUGGEST THE ONLY
KIND OF PRECIP OCCURRING...IF ANY...WOULD BE DRIZZLE AS ONLY MOISTURE
IS BLO H85 WITH DRY AIR ALOFT. EXCEPTION TO THIS WOULD BE OVER THE
NORTH AND EAST CWA SATURDAY MORNING AND THEN RETURNING TO THE
NORTHWEST CWA LATER SATURDAY NIGHT ONCE THE SFC LOW PASSES BY AND A
COLD FRONT RE-ENTERS THE PICTURE. HAVE TRENDED TOWARD THE DZ/FZDZ
IDEA FOR LATE FRIDAY NIGHT THROUGH SATURDAY. NOW IF THIS FORECAST OF
LOW LEVEL MOISTURE TRAPPED BENEATH THE WARM AIR ADVECTION ALOFT TURNS
OUT TO BE OVERDONE AS HAS OCCURRED IN THE PAST...THEN SATURDAY COULD
ACTUALLY END UP BEING AN NICE DAY WITH PARTLY SUNNY SKIES AND ABOVE
NORMAL TEMPS. MIXING TO H9 VALUES OFF THE GFS WOULD YIELD LOW 40S
OVER PARTS OF THE AREA. FOR NOW...KEPT WITH THE LOW CLOUD/DZ IDEA AND
HAVE HIGHS IN THE MID 30S.
ONCE THE COLD FRONT ARRIVES LATER SATURDAY NIGHT...PRETTY QUICK DROP
OFF IN TEMPS AT H85. ECMWF SLOWER THAN THE GFS AND PROBABLY IS MORE
ON TRACK GIVEN THE FARTHER NORTH TREND OF WARMER AIR TO START THE
WEEKEND. EVEN SO...ENOUGH COLD AIR BY SUNDAY AFTN TO START THE LAKE
EFFECT UP AGAIN FOR AREAS FAVORED BY NORTHWEST WINDS. SHORTWAVE MOVING
THROUGH SUNDAY INTO MONDAY COULD RESULT IN A PERIOD OR TWO OF LAKE
ENHANCEMENT. CORE OF COLDEST AIR ARRIVES ON MONDAY. H85 TEMPS A VERY
CHILLY -20C TO -24C...COLDEST ON THE GFS. AT LEAST LIGHT LES SHOULD
CONTINUE NEAR LK SUPERIOR AND EAST. CENTER OF HIGH PRESSURE RIDGE IS
MORE OVER THE PLAINS...SO PRESSURE GRADIENT WILL BE FAIRLY TIGHT
LEADING TO SOME LOWER WIND CHILLS ON MONDAY MORNING.
ONCE THE HIGH MOVES TOWARD THE LOWER GREAT LAKES ON TUESDAY...TEMPS
MODERATE IN WARM AIR ADVECTION ON THE BACK SIDE OF THE HIGH. COULD
BE SOME SNOW BREAK OUT OVER REGION DUE TO THE WARM AND MOIST ADVECTION.
BEST CHANCE OF THAT LOOKS TO BE NEXT TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 126 AM EST THU NOV 27 2014
WITH INCREASING SUBSIDENCE/DRY ADVECTION IN ADVANCE OF HI PRES
MOVING E FM THE NRN PLAINS...EXPECT GRADUALLY IMPROVING CONDITIONS
AT THE TAF SITES FM IFR IN THE FIRST COUPLE HRS TO PREDOMINANT MVFR.
WITH THE MOST FAVORABLE UPSLOPE/CONFLUENT N WIND...IWD WL SEE A
LONGER PERSISTENCE OF SHSN/IFR VSBYS. AS THE HI AND ACCOMPANYING
DRIER AIR EDGE CLOSER ON THANKSGIVING...THE LLVL WINDS WL BACK
TOWARD THE W BY LATE THIS AFTN AND THEN TO THE WSW THIS EVNG...
RESULTING IN A RETURN TO VFR CONDITIONS IN THE AFTN AT IWD AND SAW.
BUT MORE UPSLOPE WIND AT CMX MAY HOLD CIGS IN THE MVFR RANGE AT THAT
LOCATION THRU THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 528 AM EST THU NOV 27 2014
NW WINDS TO 25 KNOTS WILL DIMINISH TO UNDER 20 KT W TO E TODAY INTO
TONIGHT AS HIGH PRES RIDGE ARRIVES. WITH ANOTHER COLD FRONT
PUSHING ACROSS THE UPPER LAKES SAT NIGHT...EXPECT INCREASING S/SW
WINDS TO 15-25KT FRI BEHIND THE FRONT...NW WINDS MAY REACH 20-30KT
LATE SAT NIGHT AND SUN AND INCREASE TO GALES BY SUN NIGHT INTO MON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR MIZ001-
003-004.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MIZ005.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR MIZ002-009.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...KC
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
515 AM EST THU NOV 27 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 510 PM EST WED NOV 26 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS CONTINUE TO SHOW AN AMPLIFIED
PATTERN ACROSS NAMERICA WITH A RIDGE ALONG/JUST OFF THE W COAST...A
TROF EXTENDING FROM NCNTRL CANADA TO THE GULF OF MEXICO AND A RIDGE
OVER THE WRN ATLANTIC. A SHORTWAVE TROF SWINGING SE THRU NRN
ONTARIO/NRN MN IS PRODUCING SOME -SN FROM NW WI ACROSS WRN UPPER MI
INTO NRN ONTARIO. AT THE SFC...SHARPENING TROF RUNS FROM NEAR KIWD
TO JUST S OF KCMX AND THEN NE ACROSS ERN LAKE SUPERIOR. MDT TO HVY
LAKE ENHANCED SNOW IS SPREADING INTO WRN UPPER MI IN ASSOCIATION
WITH THE TROF. OFF TO THE NW...STRONG SFC HIGH PRES ACROSS
MANITOBA/SASKATCHEWAN IS BUILDING S AND E INTO THE NRN PLAINS.
PERIOD OF LAKE ENHANCED SNOW IS EXPECTED TONIGHT UNDER HEIGHT
FALLS/DEEP LAYER QVECTOR CONVERGENCE WITH SHORTWAVE SWINGING ACROSS
THE UPPER LAKES. BEST...MOST PERSISTENT LOW-LEVEL CONVERGENCE IS
INDICATED OVER THE FAR W. SO...MOST SUSTAINED MDT TO AT TIMES HVY
SNOW WILL OCCUR OVER THE FAR W FROM THE PORCUPINE MTNS TO KIWD. WITH
DGZ FALLING INTO THE LOW-LEVELS WHERE UPWARD MOTION IS FOCUSED...
EXPECT SNOW TO WATER RATIOS TO INCREASE INTO THE 20-30 TO 1 RANGE
TONIGHT. A LITTLE CONCERNED THAT THE UPWARD MOTION IS ONLY DEPICTED
IN THE LOWEST LEVELS THIS EVENING...SUGGESTING LITTLE OVERALL
SYNOPTIC SUPPORT WITH PASSING SHORTWAVE. THIS MAY TEND TO LIMIT
COVERAGE OF HVY SNOW TO ONLY THE AREAS WHERE LOW-LEVEL CONVERGENCE
IS FOCUSED. AS IT STANDS NOW...SITUATION APPEARS TO BE A MARGINAL
WARNING EVENT WITH WARNING THRESHOLDS ONLY POTENTIALLY BEING MET IN
A FEW LOCALIZED AREAS (8 INCHES OR MORE IN 12HRS OR 12 OR MORE IN
24HRS). LARGE PORTIONS OF ONTONAGON/GOGEBIC COUNTIES WILL PROBABLY
FALL IN THE 4 TO 7 INCH SNOWFALL RANGE. OF NOTE...THERE IS A FAIRLY
CONSISTENT SIGNAL AMONG MOST OF THE HIGH RES MODEL GUIDANCE FOR THE
HEAVIEST SNOW TO AFFECT LOCATIONS JUST W OF KIWD. WILL BE
INTERESTING TO SEE IF THAT INDEED DOES HAPPEN. OVER THE KEWEENAW...
SNOWFALL HAS NOT BEEN ESPECIALLY NOTEWORTHY WITH SFC TROF PASSAGE
WHICH IS WHEN THE HEAVIEST SNOWFALL WOULD LIKELY OCCUR. WITH A
DECENT LOW-LEVEL CONVERGENCE SIGNAL LACKING TONIGHT...CONSIDERED
DROPPING ADVY...BUT WILL HOLD OFF FOR NOW WITH POTENTIAL FOR SNOW TO
STILL PICK UP FOR A TIME THIS EVENING DURING THE PERIOD OF SYNOPTIC
FORCING. TO THE E...LONGER FETCH/BETTER TERRAIN ENHANCEMENT WILL
LEAD TO ANOTHER AREA OF HEAVIER SNOW DEVELOPING OVER NCNTRL UPPER MI
SPREADING FROM BARAGA COUNTY/FAR NRN MARQUETTE COUNTY EARLY THIS
EVENING TO ALGER COUNTY LATE EVENING. LOOKS LIKE SOLID ADVY AMOUNTS
FROM THE HURON MTNS TO NEGAUNEE AND EAST INTO WRN ALGER COUNTY.
POTENTIAL IS THERE FOR LOCALIZED WARNING AMOUNTS GIVEN THE
INCREASING SNOW TO WATER RATIOS AND THE LIKLIHOOD OF A LAKE NIPIGON
INITIATED DOMINANT BAND LATER TONIGHT INTO THE MORNING HRS THAT
WOULD LIKELY IMPACT LOCATIONS SOMEWHERE FROM AROUND BIG
BAY/MARQUETTE TO AROUND THE SHOT POINT AREA. IF SUCH A BAND DOES
DEVELOP AND BECOME STATIONARY FOR SEVERAL HRS...WARNING AMOUNTS MAY
BE ACHIEVED. BLSN WILL ALSO BE AN ISSUE IN THE OPEN AREAS ALONG LAKE
SUPERIOR WHERE WINDS WILL GUST OVER 30 MPH. WHILE THERE MAY BE A
BRIEF PERIOD OF HEAVIER SNOW OVER LUCE COUNTY WITH TROF PASSAGE...
SETUP AFTER TROF PASSAGE IS NOT FAVORABLE FOR ADVY SNOWFALL AMOUNTS
IN THAT AREA. ACROSS THE REST OF THE AREA...EXPECT SOME -SN FOR A
TIME TONIGHT. SOME OF THE LES OFF LAKE SUPERIOR WILL REACH NRN DELTA
AND SRN SCHOOLCRAFT COUNTIES TO PROVIDE AN INCH OR TWO OF SNOWFALL.
ON THANKSGIVING DAY...FCST SOUNDINGS SHOW INVERSIONS AT A LOW 4KFT
TO START THE DAY. LOW-LEVEL FLOW TRENDS ANTICYCLONIC DURING THE
DAY...ESPECIALLY SO OVER WRN LAKE SUPERIOR AS SFC HIGH PRES RIDGE
WILL EXTEND FROM THE MID MISSISSIPPI VALLEY N THRU WRN UPPER MI/WRN
LAKE SUPERIOR BY 00Z FRI. THESE 2 FACTORS COMBINED WITH RISING
HEIGHTS/LARGE SCALE SUBSIDENCE/QVECTOR DIVERGENCE WILL LIMIT LES
INTENSITY AND WILL RESULT IN LES DIMINISHING FROM W TO E THRU THE
DAY. IN FACT OVER THE FAR W...LES WILL END LATE IN THE AFTN AROUND
KIWD AS FLOW BACKS SW. THE ONE POSTIVE FACTOR FOR THE LES ON
THANKSGIVING DAY IS THAT THE DGZ WILL OCCUPY MOST OF THE CONVECTIVE
LAYER TO FLUFF UP SNOW ACCUMULATIONS. SO...DESPITE THE NEGATIVES
LEADING TO MOSTLY LIGHT LES ON THE WHOLE...MIGHT BE ABLE TO FLUFF UP
3-4 INCHES OF SNOW WHERE LES IS MOST PERSISTENT. THE GREATEST
ACCUMULATIONS WILL OCCUR E OF MARQUETTE WHERE LOW-LEVEL FLOW IS MORE
CYCLONIC THRU THE EARLY PART OF THE DAY AND WHERE LAKE NIPIGON
PRECONDITIONING WILL COME INTO PLAY. AWAY FROM THE MAIN LES...
SCT -SHSN/FLURRIES ARE POSSIBLE AT TIMES...EXCEPT OVER THE FAR
SCNTRL. TEMPS WILL BE UNSEASONABLY COLD ON THANKSGIVING DAY AS 850MB
THERMAL TROF (AROUND -20C) PASSES ACROSS THE AREA. EXPECT HIGHS
MOSTLY IN THE LOW/MID TEENS...TO AROUND 20F ALONG LAKE SUPERIOR AND
E. RECORD LOW MAX TEMP OF 18F HERE AT NWS MQT WILL FALL. IF TEMP
DOESN`T REACH 14F...IT WILL BE THE COLDEST MAX TEMP FOR SO EARLY IN
THE SEASON.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 509 AM EST THU NOV 27 2014
TROUGHING BRINGING THE WELL BLO NORMAL TEMPERATURES ACROSS THE AREA
TODAY EXITS OVER EASTERN CANADA AND NEW ENGLAND ON FRIDAY. UPPER
LEVEL FLOW BECOMES MORE PROGRESSIVE FROM THE PACIFIC NW ACROSS THE
NORTHERN PLAINS AND OVER THE GREAT LAKES REGION. SHORTWAVE TROUGH
CURRENTLY JUST OFFSHORE OF PACIFIC NW HEADS EAST AND WILL SUPPORT
AREA OF WARM ADVECTION/ISENTROPIC ASCENT ALONG TIGHT BAROCLINIC ZONE
SFC-H85. MODELS STILL DIFFER ON WHERE SHARPEST TEMPERATURE GRADIENT
SETS UP...BUT SEEMS THAT AT LEAST THE SOUTH HALF OF UPR MICHIGAN
SEES WIDESPREAD SNOW...WITH A BIT MORE QUESTION ON NORTHERN EXTENT.
IF BAND OF MORE CONCENTRATED SNOW SLIDES NORTHWARD THEN COULD SEE
AMOUNTS NEARING ADVY ALONG THE WI BORDER AND NEAR BAY OF GREEN BAY
FRIDAY AFTN INTO FRIDAY EVENING. PRIMARY AREA OF CONCERN STILL IS OVER
EASTERN CWA THOUGH...SCHOOLCRAFT AND LUCE COUNTIES...DUE TO LAKE
ENHANCEMENT OFF LK MICHIGAN AS THE LARGER SCALE MOISTURE AND FORCING
WITH THE SHORTWAVE COMBINES WITH MEAN BLRY SSW FLOW AND H85 TEMPS
LOWER THAN -10C...PLENTY LOW ENOUGH FOR LAKE ENHANCEMENT WITH LK
MICHIGAN WATER TEMPS AROUND UP TO 4C. IF THE FARTHER NORTH NAM IDEA
IS CORRECT WITH MORE DIRECT INFLUENCE FROM THE INCOMING SYSTEM...THEN
MODERATE TO HEAVY SNOW WOULD OCCUR. BLEND OF OTHER MODELS...INCLUDING
THE FAVORED ECMWF/GEM-NH...POINT TO SOLID ADVY AMOUNTS. WILL MENTION
IN THE HWO AND HIGHLIGHT IN EHWO GRAPHICS...BUT NOT ISSUE ANY WATCH
ATTM GIVEN THE UNCERTAINTY ON TRACK OF INCOMING SYSTEM.
MESSY FORECAST LATER FRIDAY NIGHT INTO SATURDAY. OR MAYBE IT WILL
JUST END UP BENIGN. STILL TRYING TO FIGURE THIS OUT...BUT ECMWF/GEM
AND TREND FROM GFS WOULD SUGGEST MORE DRIER IDEA. ECMWF AND GEM ARE
FARTHER NORTH WITH LARGER SCALE Q-VECTOR CONVERGENCE AND DEEP
MOISTURE TIED INTO THE NEXT SHORTWAVE/SFC LOW MOVING ACROSS IN WHAT
LOOKS MORE LIKE A ZONAL FLOW PATTERN. H85 TEMPS QUITE WARM OFF THE
ECMWF WITH +8C...YES PLUS 8...INTO SCNTRL UPR MICHIGAN BY 00Z
SUNDAY. GEM EVEN WARMER AND THE NAM/GFS IN THE BALLPARK AS WELL.
EVEN WITH THE WARMTH...SOUNDINGS FM THE NAM/GFS SUGGEST THE ONLY
KIND OF PRECIP OCCURRING...IF ANY...WOULD BE DRIZZLE AS ONLY MOISTURE
IS BLO H85 WITH DRY AIR ALOFT. EXCEPTION TO THIS WOULD BE OVER THE
NORTH AND EAST CWA SATURDAY MORNING AND THEN RETURNING TO THE
NORTHWEST CWA LATER SATURDAY NIGHT ONCE THE SFC LOW PASSES BY AND A
COLD FRONT RE-ENTERS THE PICTURE. HAVE TRENDED TOWARD THE DZ/FZDZ
IDEA FOR LATE FRIDAY NIGHT THROUGH SATURDAY. NOW IF THIS FORECAST OF
LOW LEVEL MOISTURE TRAPPED BENEATH THE WARM AIR ADVECTION ALOFT TURNS
OUT TO BE OVERDONE AS HAS OCCURRED IN THE PAST...THEN SATURDAY COULD
ACTUALLY END UP BEING AN NICE DAY WITH PARTLY SUNNY SKIES AND ABOVE
NORMAL TEMPS. MIXING TO H9 VALUES OFF THE GFS WOULD YIELD LOW 40S
OVER PARTS OF THE AREA. FOR NOW...KEPT WITH THE LOW CLOUD/DZ IDEA AND
HAVE HIGHS IN THE MID 30S.
ONCE THE COLD FRONT ARRIVES LATER SATURDAY NIGHT...PRETTY QUICK DROP
OFF IN TEMPS AT H85. ECMWF SLOWER THAN THE GFS AND PROBABLY IS MORE
ON TRACK GIVEN THE FARTHER NORTH TREND OF WARMER AIR TO START THE
WEEKEND. EVEN SO...ENOUGH COLD AIR BY SUNDAY AFTN TO START THE LAKE
EFFECT UP AGAIN FOR AREAS FAVORED BY NORTHWEST WINDS. SHORTWAVE MOVING
THROUGH SUNDAY INTO MONDAY COULD RESULT IN A PERIOD OR TWO OF LAKE
ENHANCEMENT. CORE OF COLDEST AIR ARRIVES ON MONDAY. H85 TEMPS A VERY
CHILLY -20C TO -24C...COLDEST ON THE GFS. AT LEAST LIGHT LES SHOULD
CONTINUE NEAR LK SUPERIOR AND EAST. CENTER OF HIGH PRESSURE RIDGE IS
MORE OVER THE PLAINS...SO PRESSURE GRADIENT WILL BE FAIRLY TIGHT
LEADING TO SOME LOWER WIND CHILLS ON MONDAY MORNING.
ONCE THE HIGH MOVES TOWARD THE LOWER GREAT LAKES ON TUESDAY...TEMPS
MODERATE IN WARM AIR ADVECTION ON THE BACK SIDE OF THE HIGH. COULD
BE SOME SNOW BREAK OUT OVER REGION DUE TO THE WARM AND MOIST ADVECTION.
BEST CHANCE OF THAT LOOKS TO BE NEXT TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 126 AM EST THU NOV 27 2014
WITH INCREASING SUBSIDENCE/DRY ADVECTION IN ADVANCE OF HI PRES
MOVING E FM THE NRN PLAINS...EXPECT GRADUALLY IMPROVING CONDITIONS
AT THE TAF SITES FM IFR IN THE FIRST COUPLE HRS TO PREDOMINANT MVFR.
WITH THE MOST FAVORABLE UPSLOPE/CONFLUENT N WIND...IWD WL SEE A
LONGER PERSISTENCE OF SHSN/IFR VSBYS. AS THE HI AND ACCOMPANYING
DRIER AIR EDGE CLOSER ON THANKSGIVING...THE LLVL WINDS WL BACK
TOWARD THE W BY LATE THIS AFTN AND THEN TO THE WSW THIS EVNG...
RESULTING IN A RETURN TO VFR CONDITIONS IN THE AFTN AT IWD AND SAW.
BUT MORE UPSLOPE WIND AT CMX MAY HOLD CIGS IN THE MVFR RANGE AT THAT
LOCATION THRU THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 PM EST WED NOV 26 2014
A SFC TROUGH WILL SLIDE SOUTH OVER LAKE SUPERIOR TONIGHT.
BEHIND THE TROUGH...EXPECT NORTHERLY WINDS TO 30 KTS. WINDS WILL
THEN DIMINISH TO UNDER 20 KT W TO E THU/THU NIGHT AS HIGH PRES RIDGE
ARRIVES. WITH ANOTHER COLD FRONT PUSHING ACROSS THE UPPER LAKES SAT
NIGHT...EXPECT INCREASING S/SW WINDS TO 15-25KT FRI INTO SAT AHEAD
OF FRONT. BEHIND THE FRONT...NW WINDS MAY REACH 20-30KT LATE SAT
NIGHT AND SUN AND INCREASE TO GALES BY SUN NIGHT INTO MON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006.
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THIS MORNING FOR MIZ001-
003-004.
LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THIS MORNING FOR
MIZ005.
LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ THIS
AFTERNOON FOR MIZ002-009.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
547 AM CST Thu Nov 27 2014
.SHORT TERM: (Today through Saturday)
Issued at 356 AM CST Thu Nov 27 2014
Clipper system is now well southeast of the CWFA, and only a few
lingering flurries remain. Expect any lingering precip to end by
12Z this morning and for the rest of the day to be cold and dry.
Some uncertainty on sky condition today as stratus over Iowa is
clearing fairly slowly from northwest to southeast. Short range NAM
and RAP 925mb RH field has a decent handle on the clouds at this
time, so have used a combination of these guidance products and
satellite observations to try and time gradual clearing today.
Canadian airmass over eastern Dakotas at this time will drift
southeast today and will provide the area with unseasonably cold
air. Cannot argue with MOS high temps in the mid-upper 20s to mid
30s across the area due to this cold high pressure system`s
influence.
Models continue to advertise a general pattern shift Friday into the
weekend with mid-upper level flow becoming more zonal. This will
allow warmer air to flow back into the area as the storm track
shifts north. Temperatures will moderate on Friday as the flow
shifts to the south-southwest on the western side of the Canadian
high which will have settled in over the Eastern CONUS. Expect
temperatures on Friday to be at least 10 to 15 degrees warmer than
today. Boundary layer moisture will also be on the increase, and
low level RH progs for Friday night/Saturday morning are showing
very moist conditions across the area by 12Z Saturday from about
900mb down to the surface. Have therefore increased cloud cover on
Saturday morning with some gradual clearing during the afternoon.
Models continue to spit out light QPF Saturday, but am still
skeptical due to the models` tendency to develop precipitation in
strong moisture return situations even with lifting mechanisms
aren`t present. Indeed, in this case model soundings are showing a
strong subsidence inversion in the low levels and positive values of
omega in the moist layer which would tend to lend credence to a dry
(tho cloudy/mostly cloudy) forecast for Saturday. Am still sticking
with above normal temperatures Saturday, though due to expected
cloud cover have backed off a little bit from warmest MOS guidance.
Carney
.LONG TERM: (Sunday through Wednesday)
Issued at 423 AM CST Thu Nov 27 2014
Sunday continues to look pretty mild over the majority of the area,
with the possible exception of northeast Missouri and west central
Illinois. Timing differences between the faster GFS and slower
ECMWF could mean the difference between a chilly day up north and a
day with highs between 10 and 15 degrees above normal. Leaned
toward the warmer solution this morning since the upstream shortwave
which will drive the front south is well back over Montana in the
ECMWF, and the GFS solution keeps the teeth of the shortwave up
north across the Upper Midwest. Would like to point out that this
could easily be wrong.
Cold front should be through the area by Monday morning according to
both the ECMWF and GFS with a 1040mb high building into the
Midwest. Confidence in the extended forecast beyond Monday is
pretty low as there seems to be little agreement between the GFS and
ECMWF. GFS hangs on to quasi-zonal flow aloft through Wednesday
which is mild and potentially a little wet. ECMWF develops a
full-latitude longwave trof over the eastern 1/2 of the CONUS which
would be drier and colder. Stuck with the ensemble blend of
guidance which tended toward a warmer and wetter solution for this
forecast cycle.
Carney
&&
.AVIATION: (For the 12z TAFs through 12z Friday Morning)
Issued at 545 AM CST Thu Nov 27 2014
At 1130z, ragged back edge of MVFR cloud deck extends from just
east of KALO, to near KCSQ, to around KFNB, and is working
southeast at about 20kts. This rate of movment suggests erosion of
MVFR cigs at UIN and COU around midday and in the STL metro by
mid afternoon, which dovetails fairly well with RUC 925mb RH
trends. There is a large hole in this MVFR deck is over central
and parts of S IL, but it appears to be working SE so any impacts
of this feature will miss our TAF sites. Once the low clouds clear
VFR conditions will prevail for the remainder of the forecast
period, with any additional clouds aoa 8kft overnight and into
Friday morning.
Specifics for KSTL: Bases of MVFR cigs will slowly increase as we
head through the morning and early afternoon, with this low cloud
deck finally scattering out around 22z. Once the lower deck
erodes, occasional mid level cloudiness (with bases aoa 8kft) can
expected for the remainder of the forecast period.
Truett
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 32 26 50 39 / 0 0 0 0
Quincy 24 20 45 36 / 0 0 0 0
Columbia 32 25 54 40 / 0 0 0 0
Jefferson City 33 26 56 41 / 0 0 0 0
Salem 30 23 45 37 / 5 0 0 5
Farmington 35 24 49 39 / 0 0 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
423 AM CST Thu Nov 27 2014
.SHORT TERM: (Today through Saturday)
Issued at 356 AM CST Thu Nov 27 2014
Clipper system is now well southeast of the CWFA, and only a few
lingering flurries remain. Expect any lingering precip to end by
12Z this morning and for the rest of the day to be cold and dry.
Some uncertainty on sky condition today as stratus over Iowa is
clearing fairly slowly from northwest to southeast. Short range NAM
and RAP 925mb RH field has a decent handle on the clouds at this
time, so have used a combination of these guidance products and
satellite observations to try and time gradual clearing today.
Canadian airmass over eastern Dakotas at this time will drift
southeast today and will provide the area with unseasonably cold
air. Cannot argue with MOS high temps in the mid-upper 20s to mid
30s across the area due to this cold high pressure system`s
influence.
Models continue to advertise a general pattern shift Friday into the
weekend with mid-upper level flow becoming more zonal. This will
allow warmer air to flow back into the area as the storm track
shifts north. Temperatures will moderate on Friday as the flow
shifts to the south-southwest on the western side of the Canadian
high which will have settled in over the Eastern CONUS. Expect
temperatures on Friday to be at least 10 to 15 degrees warmer than
today. Boundary layer moisture will also be on the increase, and
low level RH progs for Friday night/Saturday morning are showing
very moist conditions across the area by 12Z Saturday from about
900mb down to the surface. Have therefore increased cloud cover on
Saturday morning with some gradual clearing during the afternoon.
Models continue to spit out light QPF Saturday, but am still
skeptical due to the models` tendency to develop precipitation in
strong moisture return situations even with lifting mechanisms
aren`t present. Indeed, in this case model soundings are showing a
strong subsidence inversion in the low levels and positive values of
omega in the moist layer which would tend to lend credence to a dry
(tho cloudy/mostly cloudy) forecast for Saturday. Am still sticking
with above normal temperatures Saturday, though due to expected
cloud cover have backed off a little bit from warmest MOS guidance.
Carney
.LONG TERM: (Sunday through Wednesday)
Issued at 423 AM CST Thu Nov 27 2014
Sunday continues to look pretty mild over the majority of the area,
with the possible exception of northeast Missouri and west central
Illinois. Timing differences between the faster GFS and slower
ECMWF could mean the difference between a chilly day up north and a
day with highs between 10 and 15 degrees above normal. Leaned
toward the warmer solution this morning since the upstream shortwave
which will drive the front south is well back over Montana in the
ECMWF, and the GFS solution keeps the teeth of the shortwave up
north across the Upper Midwest. Would like to point out that this
could easily be wrong.
Cold front should be through the area by Monday morning according to
both the ECMWF and GFS with a 1040mb high building into the
Midwest. Confidence in the extended forecast beyond Monday is
pretty low as there seems to be little agreement between the GFS and
ECMWF. GFS hangs on to quasi-zonal flow aloft through Wednesday
which is mild and potentially a little wet. ECMWF develops a
full-latitude longwave trof over the eastern 1/2 of the CONUS which
would be drier and colder. Stuck with the ensemble blend of
guidance which tended toward a warmer and wetter solution for this
forecast cycle.
Carney
&&
.AVIATION: (For the 06z TAFs through 06z Thursday Night)
Issued at 1134 PM CST Wed Nov 26 2014
IFR flight conditions were widespread earlier this evening across
eastern MO and western IL into southeast IA. However over the last
few hours there has been a dramatic improvement as the surface low
redevelops in the TN valley, winds shift to north and northwesterly,
and snowfall diminishes. Radar and present trends suggest snow
should end across the St. Metro area within the next hour or two
with conditions improving at that time to MVFR. Elsewhere MVFR
conditions will persist overnight. During the day on Thursday the
cig heights are expected to gradually improve with VFR flight
conditions evolving from midday into the afternoon.
Specifics for KSTL:
Snow is expected to end by 07z with flight conditions improving at
that time to MVFR. MVFR flight conditions will then persist
through early afternoon with cig heights gradually rising, with
VFR conditions around 21z.
Glass
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 32 26 50 39 / 0 0 0 0
Quincy 24 20 45 36 / 0 0 0 0
Columbia 32 25 54 40 / 0 0 0 0
Jefferson City 33 26 56 41 / 0 0 0 0
Salem 30 23 45 37 / 5 0 0 5
Farmington 35 24 49 39 / 0 0 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1010 AM EST THU NOV 27 2014
.SYNOPSIS...
WEAK CLIPPER EXITS SOUTHERN APPALACHIANS THIS MORNING. NORTHWEST FLOW
AND LINGERING MOISTURE PRODUCE UPSLOPE SNOW THROUGH TONIGHT. HIGH
PRESSURE FRIDAY AND SATURDAY. ANOTHER SYSTEM SUNDAY NIGHT AND MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
JUST A FEW ECHOES LEFT ON THE RADAR AS THE OVERNIGHT SYSTEM
ROTATES TO THE EAST. LOW LEVEL FLOW TO TURN NORTHWESTERLY WITH A
FETCH OFF OF LAKE MICHIGAN...SO WILL KEEP CLOUDS GOING WITH
INCREASING MOUNTAIN POPS INTO THIS EVENING.
PREVIOUS DISCUSSION...
A WEAK CLIPPER SYSTEM EXITS EASTERN KY AND EASTERN TN THIS
MORNING. ON ITS WAY...LIGHT SNOW SHOWERS WILL BE POSSIBLE ACROSS
SOUTHWEST VA...AND EXTREME SOUTHERN WV DURING THE MORNING HOURS.
HOWEVER...WIND BECOMES NORTHWEST...AND WITH LINGERING
MOISTURE...UPSLOPE SNOW SHOWERS ARE LIKELY OVER THE CENTRAL AND
NORTHEAST MOUNTAINS THROUGH TONIGHT. KEPT CHANCE POPS OVER THE
WESTERN SLOPES AND EASTERN MOUNTAINS AND LIKELY POPS OVER
ELEVATIONS HIGHER THAN 3000 FEET.
MODELS INDICATE THAT BY 00Z FRIDAY...OUR AREA STILL UNDER THE BACK
EDGE OF THE H500 TROUGH...ACCOMPANY BY A STRONG ELONGATED
VORTICITY MAXIMA. H850 CHARTS SHOW EVEN COLDER AIR ADVECTING FROM THE
NORTHWEST BRINGING H850 TEMPERATURES AROUND MINUS 11C. THESE
CONDITIONS WILL COMBINE WITH THE UPSLOPE COMPONENT TO PRODUCE AN
INCH OR TWO AT HIGHER ELEVATIONS OF LIGHT SNOW LATE THURSDAY.
USED THE HRRR NUMBERS FOR HIGH TEMPERATURES TODAY...AND WENT
CLOSER TO THE COLDEST ADJECE NUMBERS FOR LOWS TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
WEAK SYSTEM PASSES BY TO THE NORTH ON SATURDAY. THEN A WEAK
BAROCLINIC ZONE DEVELOPS AND LINGERS OVER THE AREA FROM SATURDAY
THROUGH MONDAY WITH LOW POPS. FINALLY A MORE ORGANIZED SYSTEM
ROLLS THROUGH ON MONDAY...BUT MODELS VARYING WIDELY ON TIMING OF
THIS IMPULSE SO GENERALLY KEPT 30 TO 40 POPS OVER A LARGE PERIOD.
FRONT EXITS REGION ANYTIME BETWEEN MONDAY NIGHT TO TUESDAY
EVENING. NUDGED MORE TOWARDS SLOWER 00Z EURO. TOO WARM FOR SNOW
MOST PLACES DURING THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
GENERALLY USED THE ECMWF ENSEMBLE MEAN FOR THE FORECAST...WITH A BIT
OF THE GFS BLENDED IN. HIGH PRESSURE SLIDES EASTWARD SATURDAY NIGHT
AND SUNDAY...PROVIDING A SOUTHERLY FLOW. NEXT FRONTAL BOUNDARY
PUSHES INTO THE REGION SUNDAY NIGHT INTO MONDAY. HANDLING OF THIS
FRONT BEYOND MONDAY BECOMES A BIT MURKY. SOME MODELS DEVELOP A WAVE
ALONG THE FRONT FOR TUESDAY WHILE OTHERS PUSH THE FRONT TO THE SOUTH
AND DISSOLVE IT. WILL KEEP SOME SMALL POPS TUESDAY INTO WEDNESDAY
DUE TO THE UNCERTAINTY...BUT CONFIDENCE IS LOW.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
LIFR/IFR CONDITIONS DUE TO FOG AND LOW STRATUS EXPECTED TO LIFT
OFF TO MVFR/VFR AT MOST SITES BY 13-14Z. THE EXCEPTION WILL BE AT
BKW WHERE SNOW SHOWERS COULD CONTINUE DURING THE MORNING HOURS AS
A CLIPPER EXITS EASTERN KY AND EASTERN TN TODAY.
FLOW TURNS NORTHWEST LATER TODAY AND TONIGHT. A WEAKENING COLD
FRONT APPROACHES FROM THE NORTHWEST THIS EVENING. WITH LINGERING
MOISTURE...UPSLOPE SNOW SHOWERS WILL BE POSSIBLE ACROSS THE
NORTHEAST MOUNTAINS TO AFFECT EKN WITH MVFR/IFR CONDITIONS
TONIGHT.
CONFIDENCE RUNNING MEDIUM AT THIS TIME.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: VSBY OVER MOUNTAIN COUNTIES...INCLUDING
BKW...MAY BE MORE VARIABLE THAN INDICATED.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EST 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20
CRW CONSISTENCY M H H H H H H H H H H H
HTS CONSISTENCY M M M M H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H M L M
PKB CONSISTENCY H M H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z FRIDAY...
IFR CONDITIONS IN SNOW SHOWERS MAY LINGER INTO EARLY FRIDAY OVER
WV MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JW
NEAR TERM...ARJ/26
SHORT TERM...JW
LONG TERM...RPY
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
545 AM EST THU NOV 27 2014
.SYNOPSIS...
WEAK CLIPPER EXITS SOUTHERN APPALACHIANS THIS MORNING. NORTHWEST FLOW
AND LINGERING MOISTURE PRODUCE UPSLOPE SNOW THROUGH TONIGHT. HIGH
PRESSURE FRIDAY AND SATURDAY. ANOTHER SYSTEM SUNDAY NIGHT AND MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WEAK CLIPPER SYSTEM EXITS EASTERN KY AND EASTERN TN THIS
MORNING. ON ITS WAY...LIGHT SNOW SHOWERS WILL BE POSSIBLE ACROSS
SOUTHWEST VA...AND EXTREME SOUTHERN WV DURING THE MORNING HOURS.
HOWEVER...WIND BECOMES NORTHWEST...AND WITH LINGERING
MOISTURE...UPSLOPE SNOW SHOWERS ARE LIKELY OVER THE CENTRAL AND
NORTHEAST MOUNTAINS THROUGH TONIGHT. KEPT CHANCE POPS OVER THE
WESTERN SLOPES AND EASTERN MOUNTAINS AND LIKELY POPS OVER
ELEVATIONS HIGHER THAN 3000 FEET.
MODELS INDICATE THAT BY 00Z FRIDAY...OUR AREA STILL UNDER THE BACK
EDGE OF THE H500 TROUGH...ACCOMPANY BY A STRONG ELONGATED
VORTICITY MAXIMA. H850 CHARTS SHOW EVEN COLDER AIR ADVECTING FROM THE
NORTHWEST BRINGING H850 TEMPERATURES AROUND MINUS 11C. THESE
CONDITIONS WILL COMBINE WITH THE UPSLOPE COMPONENT TO PRODUCE AN
INCH OR TWO AT HIGHER ELEVATIONS OF LIGHT SNOW LATE THURSDAY.
USED THE HRRR NUMBERS FOR HIGH TEMPERATURES TODAY...AND WENT
CLOSER TO THE COLDEST ADJECE NUMBERS FOR LOWS TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
WEAK SYSTEM PASSES BY TO THE NORTH ON SATURDAY. THEN A WEAK
BAROCLINIC ZONE DEVELOPS AND LINGERS OVER THE AREA FROM SATURDAY
THROUGH MONDAY WITH LOW POPS. FINALLY A MORE ORGANIZED SYSTEM
ROLLS THROUGH ON MONDAY...BUT MODELS VARYING WIDELY ON TIMING OF
THIS IMPULSE SO GENERALLY KEPT 30 TO 40 POPS OVER A LARGE PERIOD.
FRONT EXITS REGION ANYTIME BETWEEN MONDAY NIGHT TO TUESDAY
EVENING. NUDGED MORE TOWARDS SLOWER 00Z EURO. TOO WARM FOR SNOW
MOST PLACES DURING THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
GENERALLY USED THE ECMWF ENSEMBLE MEAN FOR THE FORECAST...WITH A BIT
OF THE GFS BLENDED IN. HIGH PRESSURE SLIDES EASTWARD SATURDAY NIGHT
AND SUNDAY...PROVIDING A SOUTHERLY FLOW. NEXT FRONTAL BOUNDARY
PUSHES INTO THE REGION SUNDAY NIGHT INTO MONDAY. HANDLING OF THIS
FRONT BEYOND MONDAY BECOMES A BIT MURKY. SOME MODELS DEVELOP A WAVE
ALONG THE FRONT FOR TUESDAY WHILE OTHERS PUSH THE FRONT TO THE SOUTH
AND DISSOLVE IT. WILL KEEP SOME SMALL POPS TUESDAY INTO WEDNESDAY
DUE TO THE UNCERTAINTY...BUT CONFIDENCE IS LOW.
&&
.AVIATION /10Z THURSDAY THROUGH MONDAY/...
LIFR/IFR CONDITIONS DUE TO FOG AND LOW STRATUS EXPECTED TO LIFT
OFF TO MVFR/VFR AT MOST SITES BY 13-14Z. THE EXCEPTION WILL BE AT
BKW WHERE SNOW SHOWERS COULD CONTINUE DURING THE MORNING HOURS AS
A CLIPPER EXITS EASTERN KY AND EASTERN TN TODAY.
FLOW TURNS NORTHWEST LATER TODAY AND TONIGHT. A WEAKENING COLD
FRONT APPROACHES FROM THE NORTHWEST THIS EVENING. WITH LINGERING
MOISTURE...UPSLOPE SNOW SHOWERS WILL BE POSSIBLE ACROSS THE
NORTHEAST MOUNTAINS TO AFFECT EKN WITH MVFR/IFR CONDITIONS
TONIGHT.
CONFIDENCE RUNNING MEDIUM AT THIS TIME.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: VSBY OVER MOUNTAIN COUNTIES...INCLUDING
BKW...MAY BE MORE VARIABLE THAN INDICATED.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE THU 11/27/14
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EST 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14
CRW CONSISTENCY L L H H H H H H H H M M
HTS CONSISTENCY H H H H M H H H H M H H
BKW CONSISTENCY L H H M M H L M H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY L L M M H H M H H M H H
CKB CONSISTENCY H M M M M M H H H H H H
AFTER 12Z FRIDAY...
IFR CONDITIONS IN SNOW SHOWERS MAY LINGER INTO EARLY FRIDAY OVER
WV MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JW
NEAR TERM...ARJ
SHORT TERM...JW
LONG TERM...RPY
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS ALBANY NY
107 PM EST THU NOV 27 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL BRING SOME SCATTERED SNOW SHOWERS TO
REGION THIS AFTERNOON INTO TONIGHT. HIGH PRESSURE WILL RIDGE IN
BRIEFLY FOR FRIDAY WITH BELOW NORMAL TEMPERATURES. MILDER AIR
ATTEMPTS TO BUILD INTO THE REGION THIS WEEKEND...HOWEVER...IT WILL BE
ACCOMPANIED BY CLOUD COVER AND THE CHANCE FOR LIGHT SNOW OR RAIN
SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1255 PM EST...AN UPPER LEVEL DISTURBANCE CONTINUES TO FOCUS
SOME SCT SNOW SHOWERS OR AN AREA OF LIGHT SNOW FROM THE CAPITAL
DISTRICT SOUTH AND WEST. HAVE INCREASED THE POPS TO HIGH CHC TO
LIKELY VALUES OVER THE MID HUDSON VALLEY...ERN CATSKILLS...WRN
MOHAWK VALLEY...AND SCHOHARIE VALLEY. A SMALL AREA OF CATEGORICAL
VALUES WAS USED FOR THE ERN CATSKILLS. A DUSTING TO A HALF AN INCH
OF SNOW IS POSSIBLE...ESPECIALLY OVER THE HIGHER TERRAIN. MAX
TEMPS ARE EXPECTED TO BE IN THE M20S TO L30S OVER MOST OF THE
REGION.
PREVIOUS DISCUSSION FOR THIS PM INTO TONIGHT...
H2O VAPOR LOOP DEPICTS A DEEP TROUGH ACROSS THE EASTERN 2/3RDS OF
NOAM. A COUPLE OF RATHER POTENT SHORT WAVES WERE OBSERVED...ONE
APPROACHING THE OHIO RIVER VALLEY AND THE OTHER TRACKING INTO THE
WESTERN GREAT LAKES. TEMPERATURES ALOFT WITH THESE FEATURES ARE
QUITE COLD WITH SUB -30C AIR AT H500 AND ABOVE. NCEP MODEL SUITE
AND INTERNATIONAL GUIDANCE ARE IN GOOD AGREEMENT WITH TRACKING
THESE WAVES ACROSS THE CWFA TODAY. QG FORCING WAS PRONOUNCED LATE
THIS MORNING INTO THE AFTERNOON HOURS ALONG WITH STEEPENING LAPSE
RATES THAT SHOULD RESULT WITH AN INCREASE IN SNOW SHOWER ACTIVITY
COVERAGE. 4KM SPC AND HRRR REFLECTIVITIES DO INDICATE AN INCREASE
IN COVERAGE OF SNOW SHOWERS AS WE WILL REFLECT THIS IN THE
GRIDS/FORECAST WITH RAISING POPS. MOST OF THE HIGHER POP VALUES
WILL BE INTO THE TERRAIN WITH OROGRAPHIC LIFTING. AS FOR
ADDITIONAL ACCUMULATIONS...WE COULD SEE AN ADDITIONAL INCH OR SO.
GUIDANCE TEMPERATURES ARE VERY CLOSE...HOWEVER...WITH FRESH SNOW
COVER WE WILL LEAN TOWARD A SLIGHTLY COOLER VALUES.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
RIDGING WILL BE BUILDING INTO THE REGION...HOWEVER...LAKE EFFECT
SNOW SHOWERS DOWNWIND OF LAKE ONTARIO WILL THE MAIN WEATHER ISSUE
ON FRIDAY. LATEST NAM12 SUGGESTS THE LOW LEVEL BOUNDARY LAYER
WINDS WILL INITIALLY BE NORTHWEST...BUT AS THE RIDGE
BUILDS...THOSE WINDS BE BACKING WITH TIME. THIS WOULD SUGGEST LAKE
EFFECT ACTIVITY THAT WILL BE WEST OF THE REGION INITIALLY TO
MIGRATE INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN
DACKS. DUE TO THE MIGRATORY NATURE...THE INLAND EXTENT IS EXPECTED
TO BE LIMITED AS WE WILL KEEP POPS INTO THE CHC-SCT CATEGORY.
OTHERWISE...THE REMAINDER OF THE REGION WILL BE RATHER TRANQUIL
WITH SOME PEAKS OF SUNSHINE. AS H850 TEMPS WILL RANGE BETWEEN -12C
TO -14C...IT WILL BE UNSEASONABLY COOL FOR LATE NOVEMBER.
FRIDAY NIGHT INTO SATURDAY...HIGH PRESSURE MOVES OFF THE ATLANTIC
SEABOARD AS STORM ATTEMPTS TO ORGANIZE ACROSS THE NORTHERN PLAINS
AND GREAT LAKES REGION. THIS WILL PLACE OUR REGION INTO A WARM
ADVECTION REGIME. ALTHOUGH...LOW LEVEL MOISTURE WILL REMAIN RATHER
HIGH TO KEEP CLOUDS IN THE FORECAST. AS FOR PRECIP
POTENTIAL...BROAD ISENTROPIC LIFT WILL BE UNDERWAY WITH THE BEST
LOWERING OF THE CPD/S TO BE NORTH AND WEST OF THE CWFA.
HOWEVER...SINCE THE LOW LEVELS WILL BECOME RATHER HIGH IN MOISTURE
CONTENT...WE WILL CONTINUE WITH THE CHC POPS OF LIGHT
PRECIPITATION THROUGH THE PERIOD. MOST OF THIS PRECIP SHOULD FALL
AS WINTER TYPE BUT SOME OF THE WARMER VALLEY LOCATIONS MAY
EXPERIENCE A MIX OF RAIN/SNOW SHOWERS.
GUIDANCE TEMPERATURES DIVERGE THROUGH THE SHORT TERM AND PER THE
CURRENT SNOW PACK...WE WILL LEAN TOWARD THE COOLER SIDE OF THE
GUIDANCE ENVELOPE.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
LONG TERM PERIOD CHARACTERIZED BY CHANGEABLE WEATHER AND WIDELY
VARYING TEMPERATURES AS A SERIES OF FRONTS CROSS EASTERN NEW YORK
AND WESTERN NEW ENGLAND.
FOR SUNDAY...A WARM FRONT WILL BE CROSSING THE FORECAST AREA. FOR
NOW HAVE SLIGHT CHANCE POPS OVER MOST OF THE AREA WITH CHANCE POPS
OVER SOUTHWESTERN ADIRONDACKS AS BEST FORCING FOR ANY PRECIPITATION
MOVES NORTH OF THE AREA. AFTER A COLD THANKSGIVING WEEKEND...
TEMPERATURES SHOULD MODERATE BY LATE ON SUNDAY WITH HIGHS 40S
VALLEYS AND SOME 30S HIGHEST ELEVATIONS.
ONE OF THE MORE TRICKY PARTS OF THE EXTENDED FORECAST IS THE LOW
TEMPERATURE FORECAST ON MONDAY MORNING. THERE WILL LIKELY STILL BE
SIGNIFICANT SNOW COVER ACROSS THE AREA. IF WE CAN DECOUPLE THE
BOUNDARY LAYER FROM THE GRADIENT WIND FLOW...WITH CLEARING SKIES
TOWARD DAYBREAK...TEMPERATURES MAY FALL A GOOD TEN TO FIFTEEN
DEGREES BELOW FREEZING. FOR NOW WENT WITH LOWS AROUND FREEZING AND
THIS WILL LIKELY BE ADJUSTED AS WE GET LATER IN THE WEEKEND. A COLD
FRONT WILL CROSS THE AREA LATER MONDAY...BUT TEMPERATURES SHOULD
ONCE AGAIN REACH THE 40S IN THE VALLEYS BEFORE THE FRONT MOVES
THROUGH. A LITTLE COOLER IN THE HILLS WITH UPPER 30S FOR HIGHS.
TUESDAY LOOKS GENERALLY FAIR AND COLD BEHIND THE COLD FRONT. LOWS IN
THE TEENS AND TWENTIES AND HIGHS IN THE 20S AND 30S.
BY WEDNESDAY THE NEXT WARM FRONT IS SURGING TOWARDS THE AREA. THERE
MAY BE A BURST OF WARM ADVECTION PRECIPITATION AROUND DAYBREAK
WEDNESDAY MORNING. THIS COULD BE A MIXED BAG OF PRECIP TYPES. THE
REST OF THE DAY LOOKS CLOUDY WITH MODERATING TEMPERATURES AND
ANOTHER COLD FRONT APPROACHING QUICKLY FROM THE WEST. AS THIS COLD
FRONT MOVES THROUGH WEDNESDAY NIGHT...THERE MAY BE SOME RAIN SHOWERS
CHANGING TO SNOW SHOWERS. ANOTHER SHOT OF COLD AIR BEHIND THE FRONT
FOR THURSDAY AND FRIDAY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
WEAK UPPER LEVEL DISTURBANCE MOVING ACROSS THE REGION THIS AFTERNOON
AND THIS EVENING WILL PRODUCE CONDITIONS VARYING FROM VFR TO IFR DUE
TO LIGHT SNOW AT THE KGFL/KPOU/KALB/KPSF TAF SITES. WHEN NOT SNOWING
MAINLY VFR/MVFR CONDITIONS EXPECTED AT THE KGFL/KALB/KPOU TAF SITES
THROUGH 06Z FRIDAY...BUT MVFR CIGS AND MVFR/IFR CIGS EXPECTED EVEN
WHEN NO SNOW IS ICCURRING...WITH VFR VSBYS. WHEN SNOWING AT KPSF
EXPECT MVFR TO IFR VSBYS. FROM 06Z TONIGHT THROUGH 18Z FRIDAY EXPECT
VFR VSBYS AT THE TAF SITES...WITH MAINLY VFR CIGS.
WINDS WILL BE NORTHWESTERLY AT LESS THAN 10 KTS THROUGH FRIDAY.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...FZRA.
SUNDAY NIGHT: SLIGHT CHANCE OF SHRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SLEET.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THROUGH THE
WEEKEND.
ADDITIONAL LIGHT PRECIPITATION AMOUNTS ARE EXPECTED WITH BASIN
AVERAGES AT A TENTH OF AN INCH OR LESS EXPECTED.
MILDER TEMPS ARE POSSIBLE SUNDAY WITH SOME SNOW MELT. HOWEVER...
TEMPERATURES ARE EXPECTED TO COOL OFF QUICKLY DURING MONDAY WITH
THE PASSAGE OF A STRONG COLD FRONT.
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.
&&
.CLIMATE...
A RECORD SNOWFALL OF 9.6 INCHES WAS SET AT ALBANY NY YESTERDAY.
THIS BREAKS THE OLD RECORD OF 4.9 SET IN 1888. ALSO...THIS PLACES
THE STORM INTO ONE OF THE TOP 10 SNOWSTORMS FOR NOVEMBER FOR ALBANY.
WITH ADDITIONAL SNOWFALL EXPECTED THIS WEEKEND...WE WILL ALSO WATCH
HOW MUCH ADDS UP TO SEE WHERE WE FINISH UP FOR SNOW BY THE END OF THE
MONTH.
THE 10.4 INCHES OF SNOW AT THE ALBANY INTERNATIONAL AIRPORT PLACES
THE SNOWSTORM AS NUMBER 5 ALL-TIME FOR THE MONTH OF NOVEMBER.
TOP 5 NOVEMBER STORMS AT ALBANY 1884-2014
AMOUNT DATE YEAR
1. 22.5 INCHES 24-25 1971
2. 17.3 INCHES 14-15 1972
3. 14.1 INCHES 22-23 1943
4. 11.8 INCHES 17-18 1980
5. 10.4 INCHES 26-27 2014
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...BGM/WASULA
SHORT TERM...BGM/WASULA
LONG TERM...SND
AVIATION...GJM
HYDROLOGY...BGM/WASULA
CLIMATE...ALY STAFF
AREA FORECAST DISCUSSION
NWS ALBANY NY
1255 PM EST THU NOV 27 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL BRING SOME SCATTERED SNOW
SHOWERS TO REGION THIS AFTERNOON INTO TONIGHT. HIGH PRESSURE WILL RIDGE IN
BRIEFLY FOR FRIDAY WITH BELOW NORMAL TEMPERATURES. MILDER AIR
ATTEMPTS TO BUILD INTO THE REGION THIS WEEKEND...HOWEVER...IT WILL BE
ACCOMPANIED BY CLOUD COVER AND THE CHANCE FOR LIGHT SNOW OR RAIN
SHOWERS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1255 PM EST...AN UPPER LEVEL DISTURBANCE CONTINUES TO FOCUS
SOME SCT SNOW SHOWERS OR AN AREA OF LIGHT SNOW FROM THE CAPITAL
DISTRICT SOUTH AND WEST. HAVE INCREASED THE POPS TO HIGH CHC TO
LIKELY VALUES OVER THE MID HUDSON VALLEY...ERN CATSKILLS...WRN
MOHAWK VALLEY...AND SCHOHARIE VALLEY. A SMALL AREA OF CATEGORICAL
VALUES WAS USED FOR THE ERN CATSKILLS. A DUSTING TO A HALF AN INCH
OF SNOW IS POSSIBLE...ESPECIALLY OVER THE HIGHER TERRAIN. MAX
TEMPS ARE EXPECTED TO BE IN THE M20S TO L30S OVER MOST OF THE
REGION.
PREVIOUS DISCUSSION FOR THIS PM INTO TONIGHT...
H2O VAPOR LOOP DEPICTS A DEEP TROUGH ACROSS THE EASTERN 2/3RDS OF
NOAM. A COUPLE OF RATHER POTENT SHORT WAVES WERE OBSERVED...ONE
APPROACHING THE OHIO RIVER VALLEY AND THE OTHER TRACKING INTO THE
WESTERN GREAT LAKES. TEMPERATURES ALOFT WITH THESE FEATURES ARE
QUITE COLD WITH SUB -30C AIR AT H500 AND ABOVE. NCEP MODEL SUITE
AND INTERNATIONAL GUIDANCE ARE IN GOOD AGREEMENT WITH TRACKING
THESE WAVES ACROSS THE CWFA TODAY. QG FORCING WAS PRONOUNCED LATE
THIS MORNING INTO THE AFTERNOON HOURS ALONG WITH STEEPENING LAPSE
RATES THAT SHOULD RESULT WITH AN INCREASE IN SNOW SHOWER ACTIVITY
COVERAGE. 4KM SPC AND HRRR REFLECTIVITIES DO INDICATE AN INCREASE
IN COVERAGE OF SNOW SHOWERS AS WE WILL REFLECT THIS IN THE
GRIDS/FORECAST WITH RAISING POPS. MOST OF THE HIGHER POP VALUES
WILL BE INTO THE TERRAIN WITH OROGRAPHIC LIFTING. AS FOR
ADDITIONAL ACCUMULATIONS...WE COULD SEE AN ADDITIONAL INCH OR SO.
GUIDANCE TEMPERATURES ARE VERY CLOSE...HOWEVER...WITH FRESH SNOW
COVER WE WILL LEAN TOWARD A SLIGHTLY COOLER VALUES.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
RIDGING WILL BE BUILDING INTO THE REGION...HOWEVER...LAKE EFFECT
SNOW SHOWERS DOWNWIND OF LAKE ONTARIO WILL THE MAIN WEATHER ISSUE
ON FRIDAY. LATEST NAM12 SUGGESTS THE LOW LEVEL BOUNDARY LAYER
WINDS WILL INITIALLY BE NORTHWEST...BUT AS THE RIDGE
BUILDS...THOSE WINDS BE BACKING WITH TIME. THIS WOULD SUGGEST LAKE
EFFECT ACTIVITY THAT WILL BE WEST OF THE REGION INITIALLY TO
MIGRATE INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN
DACKS. DUE TO THE MIGRATORY NATURE...THE INLAND EXTENT IS EXPECTED
TO BE LIMITED AS WE WILL KEEP POPS INTO THE CHC-SCT CATEGORY.
OTHERWISE...THE REMAINDER OF THE REGION WILL BE RATHER TRANQUIL
WITH SOME PEAKS OF SUNSHINE. AS H850 TEMPS WILL RANGE BETWEEN -12C
TO -14C...IT WILL BE UNSEASONABLY COOL FOR LATE NOVEMBER.
FRIDAY NIGHT INTO SATURDAY...HIGH PRESSURE MOVES OFF THE ATLANTIC
SEABOARD AS STORM ATTEMPTS TO ORGANIZE ACROSS THE NORTHERN PLAINS
AND GREAT LAKES REGION. THIS WILL PLACE OUR REGION INTO A WARM
ADVECTION REGIME. ALTHOUGH...LOW LEVEL MOISTURE WILL REMAIN RATHER
HIGH TO KEEP CLOUDS IN THE FORECAST. AS FOR PRECIP
POTENTIAL...BROAD ISENTROPIC LIFT WILL BE UNDERWAY WITH THE BEST
LOWERING OF THE CPD/S TO BE NORTH AND WEST OF THE CWFA.
HOWEVER...SINCE THE LOW LEVELS WILL BECOME RATHER HIGH IN MOISTURE
CONTENT...WE WILL CONTINUE WITH THE CHC POPS OF LIGHT
PRECIPITATION THROUGH THE PERIOD. MOST OF THIS PRECIP SHOULD FALL
AS WINTER TYPE BUT SOME OF THE WARMER VALLEY LOCATIONS MAY
EXPERIENCE A MIX OF RAIN/SNOW SHOWERS.
GUIDANCE TEMPERATURES DIVERGE THROUGH THE SHORT TERM AND PER THE
CURRENT SNOW PACK...WE WILL LEAN TOWARD THE COOLER SIDE OF THE
GUIDANCE ENVELOPE.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
LONG TERM PERIOD CHARACTERIZED BY CHANGEABLE WEATHER AND WIDELY
VARYING TEMPERATURES AS A SERIES OF FRONTS CROSS EASTERN NEW YORK
AND WESTERN NEW ENGLAND.
FOR SUNDAY...A WARM FRONT WILL BE CROSSING THE FORECAST AREA. FOR
NOW HAVE SLIGHT CHANCE POPS OVER MOST OF THE AREA WITH CHANCE POPS
OVER SOUTHWESTERN ADIRONDACKS AS BEST FORCING FOR ANY PRECIPITATION
MOVES NORTH OF THE AREA. AFTER A COLD THANKSGIVING WEEKEND...
TEMPERATURES SHOULD MODERATE BY LATE ON SUNDAY WITH HIGHS 40S
VALLEYS AND SOME 30S HIGHEST ELEVATIONS.
ONE OF THE MORE TRICKY PARTS OF THE EXTENDED FORECAST IS THE LOW
TEMPERATURE FORECAST ON MONDAY MORNING. THERE WILL LIKELY STILL BE
SIGNIFICANT SNOW COVER ACROSS THE AREA. IF WE CAN DECOUPLE THE
BOUNDARY LAYER FROM THE GRADIENT WIND FLOW...WITH CLEARING SKIES
TOWARD DAYBREAK...TEMPERATURES MAY FALL A GOOD TEN TO FIFTEEN
DEGREES BELOW FREEZING. FOR NOW WENT WITH LOWS AROUND FREEZING AND
THIS WILL LIKELY BE ADJUSTED AS WE GET LATER IN THE WEEKEND. A COLD
FRONT WILL CROSS THE AREA LATER MONDAY...BUT TEMPERATURES SHOULD
ONCE AGAIN REACH THE 40S IN THE VALLEYS BEFORE THE FRONT MOVES
THROUGH. A LITTLE COOLER IN THE HILLS WITH UPPER 30S FOR HIGHS.
TUESDAY LOOKS GENERALLY FAIR AND COLD BEHIND THE COLD FRONT. LOWS IN
THE TEENS AND TWENTIES AND HIGHS IN THE 20S AND 30S.
BY WEDNESDAY THE NEXT WARM FRONT IS SURGING TOWARDS THE AREA. THERE
MAY BE A BURST OF WARM ADVECTION PRECIPITATION AROUND DAYBREAK
WEDNESDAY MORNING. THIS COULD BE A MIXED BAG OF PRECIP TYPES. THE
REST OF THE DAY LOOKS CLOUDY WITH MODERATING TEMPERATURES AND
ANOTHER COLD FRONT APPROACHING QUICKLY FROM THE WEST. AS THIS COLD
FRONT MOVES THROUGH WEDNESDAY NIGHT...THERE MAY BE SOME RAIN SHOWERS
CHANGING TO SNOW SHOWERS. ANOTHER SHOT OF COLD AIR BEHIND THE FRONT
FOR THURSDAY AND FRIDAY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
MVFR CONDITIONS ARE OCCURRING ACROSS MOST OF THE ALBANY FORECAST
AREA THIS MORNING. THE EXCEPTION IS KPOU WHICH IS CURRENTLY VFR
BUT HAS BEEN BOUNCING BETWEEN VFR AND IFR DUE TO FOG. A BRIEF
PERIOD OF VFR IS EXPECTED AT THE TAF SITES THIS MORNING BEFORE A
VIGOROUS COLD UPPER LEVEL TROUGH BRINGS ANOTHER CHANCE FOR SNOW
LATER TODAY TO THE AREA WITH MVFR CONDITIONS EXPECTED AT ALL THE
TAF SITES BY LATER THIS AFTERNOON OR THIS EVENING. A LIGHT
ACCUMULATING SNOW IS AGAIN POSSIBLE WITH THIS SYSTEM. IMPROVEMENT
TO VFR CONDITIONS EXPECTED BY MID MORNING FRIDAY.
WINDS WILL BE NORTHWESTERLY AT LESS THAN 10 KTS THROUGH FRIDAY.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...FZRA.
SUNDAY NIGHT: SLIGHT CHANCE OF SHRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SLEET.
MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THROUGH THE
WEEKEND.
ADDITIONAL LIGHT PRECIPITATION AMOUNTS ARE EXPECTED WITH BASIN
AVERAGES AT A TENTH OF AN INCH OR LESS EXPECTED.
MILDER TEMPS ARE POSSIBLE SUNDAY WITH SOME SNOW MELT. HOWEVER...
TEMPERATURES ARE EXPECTED TO COOL OFF QUICKLY DURING MONDAY WITH
THE PASSAGE OF A STRONG COLD FRONT.
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.
&&
.CLIMATE...
A RECORD SNOWFALL OF 9.6 INCHES WAS SET AT ALBANY NY YESTERDAY.
THIS BREAKS THE OLD RECORD OF 4.9 SET IN 1888. ALSO...THIS PLACES
THE STORM INTO ONE OF THE TOP 10 SNOWSTORMS FOR NOVEMBER FOR ALBANY.
WITH ADDITIONAL SNOWFALL EXPECTED THIS WEEKEND...WE WILL ALSO WATCH
HOW MUCH ADDS UP TO SEE WHERE WE FINISH UP FOR SNOW BY THE END OF THE
MONTH.
THE 10.4 INCHES OF SNOW AT THE ALBANY INTERNATIONAL AIRPORT PLACES
THE SNOWSTORM AS NUMBER 5 ALL-TIME FOR THE MONTH OF NOVEMBER.
TOP 5 NOVEMBER STORMS AT ALBANY 1884-2014
AMOUNT DATE YEAR
1. 22.5 INCHES 24-25 1971
2. 17.3 INCHES 14-15 1972
3. 14.1 INCHES 22-23 1943
4. 11.8 INCHES 17-18 1980
5. 10.4 INCHES 26-27 2014
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...BGM/WASULA
SHORT TERM...BGM/WASULA
LONG TERM...SND
AVIATION...SND
HYDROLOGY...BGM/WASULA
CLIMATE...ALY STAFF
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1208 PM CST THU NOV 27 2014
.SHORT TERM...
337 AM CST
THROUGH FRIDAY...
THOSE DREAMING OF A WHITE THANKSGIVING WILL LIKELY NEED TO BE
DOWNWIND OF THE LAKE ALONG THE INDIANA AND MICHIGAN SHORES
TODAY...ALTHOUGH DURING THE PREDAWN HOURS THERE HAVE BEEN SEVERAL
STATIONS REPORTING PERSISTENT FLURRIES BUT NO ACCUMULATION ON THE
ILLINOIS SIDE AS WELL. AFTERNOON HIGHS LIKELY WILL TOP OUT A FEW
DEGREES COOLER THAN WHAT WOULD BE MORE TYPICAL FOR CHRISTMAS THAN
LATE NOVEMBER...SO EVEN IN AREAS THAT DO NOT RECEIVE SNOW IT WILL
STILL BE QUITE A COLD THANKSGIVING.
PERHAPS THE MOST WELCOME NEWS COMES ON FRIDAY INTO THE WEEKEND WHEN
TEMPERATURES SHOULD FINALLY CLIMB BACK INTO NORMAL RANGES...AND
LIKELY WELL ABOVE. COLD NORTHERLY FLOW AHEAD OF AN APPROACHING HIGH
IS WHAT WILL BE KEEPING THE LID ON TEMPERATURES TODAY...BUT WINDS
TURN SOUTH BY FRIDAY AND START TO PUSH THE COLD AIR AWAY TO OUR
NORTHEAST AS THE HIGH DROPS INTO THE OHIO VALLEY.
LENNING
&&
.LONG TERM...
337 AM CST
FRIDAY NIGHT THROUGH THURSDAY...
WITH WEAK TO MODERATE WARM ADVECTION LATE FRIDAY INTO FRIDAY
NIGHT AND SATURDAY...TEMPERATURE TRENDS OVERNIGHT COULD BE FLAT TO
SLOWLY RISING. WARM ADVECTION THEN DEVELOPS IN EARNEST DURING THE
DAY SATURDAY AHEAD OF A CENTER OF LOW PRESSURE SLIDING ACROSS THE
NORTHERN CONUS AND INTO THE NORTHERN GREAT LAKES BY SATURDAY
NIGHT.
AS THE NORTHERN LAKES LOW LIFTS INTO ONTARIO AND QUEBEC ON
SUNDAY...A TRAILING COLD FRONT MAKES ITS WAY ACROSS THE LOCAL AREA.
ASIDE FROM THE AREAS GETTING LAKE EFFECT SNOW TODAY...THIS FRONTAL
PASSAGE LIKELY BRINGS THE BEST CHANCE OF PRECIPITATION OVER THE NEXT
FEW DAYS...AND RIGHT NOW THERE ONLY APPEARS TO BE A CHANCE OR SLIGHT
CHANCE...PRIMARILY IN THE SOUTHEAST PART OF THE AREA. THE ECMWF AND
NAM ARE SLOWER THAN THE GFS WITH THE PROGRESSION OF THIS
FEATURE...SO BY LEANING TOWARD THOSE SOLUTIONS WE ALLOW AT LEAST THE
SOUTHERN PORTIONS OF THE AREA TO EXPERIENCE ANOTHER MILD LATE
NOVEMBER DAY BEFORE THE COLD AIR RETURNS FOR EARLY NEXT WEEK.
WITH QUASI ZONAL FLOW IN PLACE ALOFT NEXT WEEK AND A PROGRESSIVE
PATTERN AT THE SURFACE...THE SHARP POST FRONTAL COOLDOWN LATE SUNDAY
INTO MONDAY LIKELY WILL EVOLVE INTO ANOTHER BRIEF WARMUP ABOVE
FREEZING ON TUESDAY AND WEDNESDAY...THOUGH NOT AS WARM AS THIS
WEEKEND AND MAYBE NOT EVEN QUITE UP TO TYPICAL HIGHS.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* MVFR CIG TRENDS INTO EARLY-MID AFTERNOON.
* POTENTIAL FOR A PERIOD OF SNOW EARLY FRIDAY MORNING.
* GUSTY SOUTHERLY WINDS MID FRIDAY MORNING THROUGH THE AFTERNOON.
RC
//DISCUSSION...UPDATED 18Z...
MAIN AVIATION CONCERN IS POTENTIAL FOR A SHORT PERIOD OF SNOW
EARLY FRIDAY MORNING. PRIOR TO THAT...STILL EXPECTING MVFR CIGS TO
SCATTER THIS AFTERNOON AND GUSTY NORTHWEST WINDS TO DIMINISH EARLY
THIS EVENING AS HIGH PRESSURE MOVES OVERHEAD. REGARDING THE PERIOD
OF SNOW...MAIN QUESTION IS IF SATURATION OCCURS WHILE GOOD FORCING
PASSES ACROSS THE AREA IN THE EARLY MORNING HOURS. IF IT
DOES...LOOKING AT A FAIRLY NARROW BAND OF SNOW TO TRACK WEST TO
EAST...WITH GYY POSSIBLY ON THE SOUTHERN FRINGE. HAVE INTRODUCED
A 3-4 HR PROB 30 IN THE TAFS...BUT SNOW IS ONLY FAVORED TO LAST
1-2 HOURS AT MOST UPON ONSET...WITH UNDER 1 INCH OF ACCUMULATION.
SHOULD THE ORGANIZED BAND OF SNOW MATERIALIZE...THEN IFR TO LOWER
MVFR VSBY WOULD BE LIKELY.
AFTER ANY SNOW ENDS...CONCERN SHIFTS TO GUSTY SOUTHERLY WINDS
(160-180 DEG) DEVELOPING IN THE MID/LATE MORNING AND CONTINUING
THROUGH THE AFTERNOON ON FRIDAY. GUSTS COULD BE IN THE LOW 20KT
RANGE AND POTENTIALLY HIGHER IF MIXING IS A BIT DEEPER. VFR
CONDITIONS ARE EXPECTED DURING THE STRONGER SOUTHERLY WINDS.
RC
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM IN TIMING OF MVFR CIGS SCATTERING THIS AFTERNOON.
* LOW IN SHORT PERIOD OF STEADY SNOW OCCURRING EARLY
FRIDAY...MEDIUM IN TIMING.
* HIGH IN WIND TRENDS.
RC
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...VFR.
SUNDAY...SLIGHT CHANCE OF RAIN.
MONDAY...VFR.
TUESDAY...SLIGHT CHANCE OF LIGHT SNOW LATE.
WEDNESDAY...SLIGHT CHANCE OF LIGHT SNOW.
RODRIGUEZ
&&
.MARINE...
424 AM CST
FRONTAL BOUNDARY PUSHING DOWN THE LAKE EARLY THIS MORNING AND AS
THIS IS OCCURRING...NORTHWEST WINDS ARE RAPIDLY INCREASING UP TO
30 KT. THIS TREND WILL CONTINUE IN THE NEAR TERM WITH ALL AREAS
ACROSS THE OPEN WATERS OBSERVING NORTHWEST 30 KT WINDS TODAY.
ALTHOUGH IT DOES APPEAR TO BE BRIEF...OCCASIONAL GALE FORCE GUSTS
STILL APPEAR TO BE POSSIBLE TODAY AND SO HAVE CONTINUED THE
MENTION IN THE OPEN WATERS FORECAST. FOR THE NEARSHORE
TODAY...NORTHWEST WINDS WILL PREVAIL WITH THE STRONGEST LIKELY
OBSERVED IN THE INDIANA NEARSHORE. THIS IS ALREADY OCCURRING AND
SO HAVE STARTED THE SCA FOR INDIANA NOW AND THEN EXTENDED IT
FURTHER INTO TONIGHT...AS HIGHER WAVES WILL LINGER FOR MOST OF
TONIGHT. AFTER A BRIEF LULL IN SPEEDS TONIGHT AS HIGH PRESSURE
MOVES ACROSS THE REGION...WINDS WILL TURN TO THE SOUTHWEST AND
SOUTH ON FRIDAY. SOUTHERLY WINDS ARE EXPECTED TO INCREASE OVER THE
LAKE AND NEARSHORE WATERS...WITH SPEEDS UP TO 30 KT LIKELY OVER
THE OPEN WATERS FRIDAY AND FRIDAY EVENING. THERE ONCE AGAIN
APPEARS TO BE A POSSIBILITY FOR SPEEDS APPROACHING GALE
FORCE...ESPECIALLY IN THE AFTERNOON AND EARLY EVENING OVER THE
ENTIRE LAKE. HAVE MADE MENTION OF GALE FORCE GUSTS ONCE AGAIN
DURING THIS TIME...BUT CONFIDENCE OF THESE HIGHER SPEEDS IS LOW.
WILL NEED TO MONITOR THESE PERIODS...WITH THE POSSIBILITY OF THESE
HIGHER SPEEDS BEING OBSERVED.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 4 AM FRIDAY.
SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 6 PM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1123 AM CST Thu Nov 27 2014
.UPDATE...
ISSUED AT 1000 AM CST THU NOV 27 2014
Have updated the forecast to significantly ramp up the PoP`s for
the next few hours from about Decatur northwest to Galesburg. An
area of light snow and flurries has been moving southeast out of
the Quad Cities. While significant accumulation is not
anticipated, the visibilities have been getting down to 1 to 2
miles at times which would imply more than just flurries, and
web cams around Peoria suggest a dusting of accumulation is
occurring in the heavier bands. The snow has been weakening as it
moves southeast through central Illinois, so have kept the
afternoon dry for now. Back edge of the cloud deck is along the
Illinois/Iowa border and slowly moving east, with the RAP guidance
continuing to indicate some gradual clearing from west to east
across our forecast area this afternoon.
&&
.SHORT TERM...(Today)
ISSUED AT 321 AM CST THU NOV 27 2014
08z/2am surface analysis shows clipper system tracking southeastward
through the Ohio River Valley, while high pressure builds into the
Northern Plains. Accumulating snow associated with the clipper has
ended, leaving behind mostly cloudy and cold conditions. Main
short-term forecast challenge will be timing the clearing trend
later today. Current IR satellite imagery shows clouds blanketing
the region, with the back edge evident across southeast Minnesota
into north-central Iowa. Based solely on satellite timing tools,
clearing would arrive in the Illinois River Valley between 15z
and 17z. However, with continued deep-layer northwesterly flow
and very cold air aloft, think clouds may tend to re-develop along
the back edge of the main cloud area, thus slowing the overall
eastward progression of the clearing. Negative Cu-rule values
support this theory, as does the latest HRRR. As a result, have
decided to go with an overcast morning across the board, followed
by a slow northwest to southeast clearing this afternoon. Some
locations along/east of I-57 will likely remain cloudy through the
entire day. Due to the cloud cover and gusty northwesterly winds,
high temperatures will remain in the 20s across most of the area,
with a few lower 30s south of I-70.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 321 AM CST THU NOV 27 2014
After chilly low temperatures in the teens tonight, a major
warming trend will get underway by the end of the week. High
pressure will shift east of the region on Friday, allowing gusty
southerly winds to develop. Despite partial sunshine and strong
WAA, warming trend will be mitigated by existing snow cover along
a Rushville...to Springfield...to Robinson line. Have therefore
lowered highs across this area by 3-4 degrees, with readings
reaching the lower 40s. Much warmer weather is expected
everywhere on Saturday as strong southerly flow continues. Models
are showing a fetch of increasing low-level moisture from the
western Gulf of Mexico northward into central Illinois, with
surface dew points increasing from the lower 30s early in the day
to well into the 40s to near 50 degrees late. Forecast soundings
are showing saturation below 850mb, which suggests increasing
low-level cloudiness. Have therefore gone with a mostly cloudy
forecast with high temperatures reaching the lower to middle 50s.
Another warm day is expected on Sunday, although an approaching
cold front may trigger scattered showers across the central and
southern zones as the day progresses. Front will drop into the Ohio
River Valley by Sunday night, with a colder air mass settling
southward early next week. Model discrepancies still exist Sunday
night, with the ECMWF trying to develop some light precip
along/north of the boundary into the colder air mass. Meanwhile, the
GFS keeps the light precip confined to areas along/south of the
front. With no clear upper wave to support the post-frontal precip,
have opted to side with the GFS here, resulting in dry weather
across all but the far SE CWA where a few rain showers may linger.
After that, major model differences arise by the middle of next week
as all are in poor agreement concerning the evolution of a closed
upper low over the central Pacific. 00z Nov 27 GFS shows this
feature shearing eastward across the central CONUS, eventually
triggering overrunning precip across Illinois by
Wednesday/Thursday. The ECMWF takes the low and gradually absorbs
it into a stronger low over the Gulf of Alaska, with a downstream
trough providing cool/dry weather to Illinois on
Wednesday/Thursday. Meanwhile, the GEM keeps the low off the coast
of California the entire time and also features a cool/dry forecast
for Illinois. With so much uncertainty, decided to make very few
changes to the going forecast beyond Monday. For now will maintain
dry weather through Wednesday with a gradual warming trend.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1123 AM CST THU NOV 27 2014
Small area of light snow showers has been reducing visibilities to
1 to 2 miles as it moves southeast. Currently moving through KDEC
and may clip KCMI over the next hour or two, although it will
largely track south of there. Otherwise, MVFR conditions will
prevail into mid afternoon, although an area of clearing is not
too far west of KPIA and will be spreading eastward through the
afternoon. Later on in the forecast period, northwest winds to
turn more southeast overnight, following the passage of an area of
high pressure. Strong low level winds will arrive on Friday
morning and mix down toward the surface, producing some gusts up
to 15-20 knots by mid to late morning. Some higher clouds around
8000 feet or so will move through overnight and exit Friday
morning, as a clipper system passes to our north.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1017 AM MST THU NOV 27 2014
.UPDATE...
ISSUED AT 911 AM MST THU NOV 27 2014
MADE ADJUSTMENTS TO THE TEMPERATURE FORECAST FOR TODAY. BASED ON
LATEST OBSERVATIONS...THE REGION WAS GENERALLY RUNNING ABOUT 6-8
DEGREES COOLER THAN ADVERTISED. LATEST RAP AND HRRR GUIDANCE
SHOWED A SLOWER TREND FOR WARMING TEMPERATURES AS WELL. THINK THE
MAIN CULPRIT FOR THE COOLER TEMPERATURES IS A STOUT INVERSION
ERODING MUCH SLOWER THAN MOST GUIDANCE FORECAST PROJECTED. BASED
ON LATEST RAP FORECAST SOUNDINGS...THE INVERSION ERODES VERY
SLOWLY THIS MORNING AND MAY FINALLY BE OVER COME BY LATE THIS
AFTERNOON. BY THEN...IT WILL LIKELY BE TOO LATE TO GET SIGNIFICANT
WARMING AND REACH HIGH TEMPERATURE FORECAST. THEREFORE...LOWERED
THE HIGHS FOR TODAY AND SLOWED HOURLY TEMPERATURE TREND SIMILAR TO
THAT OF THE HRRR. DRY FORECAST REMAINS WITH CLOUDS INCREASING LATE
IN THE DAY. LATEST GRIDS SENT.
UPDATE ISSUED AT 548 AM MST THU NOV 27 2014
UPDATE SENT FOR MINOR TEMP ADJUSTMENTS OFF LATEST SET OF HOURLIES.
OTHERWISE...REST OF FORECAST IN GOOD SHAPE AS REGION WILL WAIT FOR
HIGH CLOUDS OVER THE ROCKIES TO FILTER OVER CWA.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 235 AM MST THU NOV 27 2014
FOR THE SHORT TERM PERIOD...MODELS HAVE BROAD UPPER RIDGE OVER THE
WESTERN PORTION OF THE COUNTRY TODAY...WITH A MID-LEVEL TROUGH OVER
THE EASTERN HALF. GOING INTO THE UPCOMING WEEKEND...UPPER FLOW
SET TO BECOME MORE ZONAL AS TROUGH BEGINS TO DIG SOUTH INTO THE
PACIFIC NORTHWEST. FOR TODAY THOUGH...SHORTWAVE IS EXPECTED TO
WORK THRU THE UPPER RIDGE AND BRING MID/HIGHS CLOUDS TO THE AREA
BEFORE CLEARING OUT. WITH ZONAL FLOW DEVELOPING BY THE START OF
THE WEEKEND...THIS IS EXPECTED TO BE COMPLIMENTED BY A SURFACE
LEE-SIDE TROUGH OVER THE EAST SIDE OF THE ROCKIES...AIDING TO
PROVIDE A STRONGER WAA UNDER SSW FLOW FRIDAY RIGHT INTO SATURDAY
NIGHT. WITH STRONG RIDGING OVER THE AREA...MODEL 850/925 TEMPS
WILL RANGE FROM +14C TODAY...UP TO +20C BY FRIDAY...BEFORE
TAPERING BACK DOWN BY LATE IN THE WEEKEND. OVERALL...THE CWA WILL
SEE GOOD CHANCE FOR 70S FOR HIGHS TODAY INTO SATURDAY ESPECIALLY
FOR WESTERN ZONES. THIS IS GOING TO SET THE AREA FOR 10-15 DEGREES
ABOVE NORMAL FOR HIGHS AND SEVERAL DEGREES ABOVE CURRENT TRENDS
FOR OVERNIGHT LOWS. NO PRECIP IS EXPECTED TO AFFECT THE TRI STATE
REGION THRU SATURDAY NIGHT...ALTHOUGH A FRONT MOVING SOUTHWARD
LATE SUNDAY WILL WORK INTO THE REGION.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 235 AM MST THU NOV 27 2014
SUNDAY THROUGH WEDNESDAY WILL START OUT WITH A STRONG COLD FRONT
MOVING THROUGH THE AREA ON SUNDAY MORNING. BEHIND THE FRONT WELL
BELOW NORMAL TEMPERATURES WILL MOVE INTO THE AREA. AM NOT EXPECTING
ANY PRECIPITATION WITH THE FRONTAL PASSAGE DUE TO THE 1000-500MB
MOISTURE AND MAIN UPPER LEVEL TROUGH REMAINING OVER THE NORTHERN
PLAINS. WIND CHILLS WILL DROP TO AROUND ZERO SUNDAY NIGHT AS THE
COLD AIR MASS SETTLES OVER THE AREA.
A SECOND LESS INTENSE COLD FROM WILL MOVE THROUGH THE AREA TUESDAY
NIGHT. THERE IS SOME UNCERTAINTY ABOUT PRECIPITATION DEVELOPMENT
ASSOCIATED WITH THE UPPER LEVEL TROUGH MOVING OFF THE WEST COAST
BEHIND THE FRONT FROM TUESDAY NIGHT. MODELS DISAGREE HOW FAST THE
UPPER LEVEL TROUGH WILL MOVE THROUGH...WITH THE SLOWER ONE HAVING
DRY NORTHWEST FLOW OVER THE AREA DUE TO THE TROUGH STILL OUT TO SEA.
THE FASTER OTHER MODEL HAS MOIST WEST FLOW OVER THE AREA AS THE
TROUGH MOVES THROUGH. AT THIS POINT WILL NOT DEVIATE FROM WHAT THE
INITIAL MODEL BLEND GAVE WHICH HAS LOW PRECIP. CHANCES IN FOR
VARIOUS PARTS OF THE AREA WEDNESDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1017 AM MST THU NOV 27 2014
VFR CONDITIONS EXPECTED FOR THE NEXT 24 HOURS. A VERY DRY AIRMASS
IS ADVECTING INTO THE REGION...LEADING TO MOSTLY CLEAR SKIES.
ONLY POSSIBLE CLOUD COVER IS HIGH LEVEL CIRRUS MOVING IN FROM THE
FRONT RANGE. A LEE TROUGH HAS DEVELOPED OVER CENTRAL COLORADO...
LEADING TO SOUTHWEST WINDS AT KGLD AND SOUTH WINDS AT KMCK
TODAY. LEE TROUGH PASSES THROUGH TONIGHT WITH WINDS VEERING TO THE
WEST AFTER TROUGH PASSAGE. WINDS 8-12 KNOTS THROUGHOUT THE
FORECAST PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...RRH
SHORT TERM...JN
LONG TERM...JTL
AVIATION...RRH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
911 AM MST THU NOV 27 2014
.UPDATE...
ISSUED AT 911 AM MST THU NOV 27 2014
MADE ADJUSTMENTS TO THE TEMPERATURE FORECAST FOR TODAY. BASED ON
LATEST OBSERVATIONS...THE REGION WAS GENERALLY RUNNING ABOUT 6-8
DEGREES COOLER THAN ADVERTISED. LATEST RAP AND HRRR GUIDANCE
SHOWED A SLOWER TREND FOR WARMING TEMPERATURES AS WELL. THINK THE
MAIN CULPRIT FOR THE COOLER TEMPERATURES IS A STOUT INVERSION
ERODING MUCH SLOWER THAN MOST GUIDANCE FORECAST PROJECTED. BASED
ON LATEST RAP FORECAST SOUNDINGS...THE INVERSION ERODES VERY
SLOWLY THIS MORNING AND MAY FINALLY BE OVER COME BY LATE THIS
AFTERNOON. BY THEN...IT WILL LIKELY BE TOO LATE TO GET SIGNIFICANT
WARMING AND REACH HIGH TEMPERATURE FORECAST. THEREFORE...LOWERED
THE HIGHS FOR TODAY AND SLOWED HOURLY TEMPERATURE TREND SIMILAR TO
THAT OF THE HRRR. DRY FORECAST REMAINS WITH CLOUDS INCREASING LATE
IN THE DAY. LATEST GRIDS SENT.
UPDATE ISSUED AT 548 AM MST THU NOV 27 2014
UPDATE SENT FOR MINOR TEMP ADJUSTMENTS OFF LATEST SET OF HOURLIES.
OTHERWISE...REST OF FORECAST IN GOOD SHAPE AS REGION WILL WAIT FOR
HIGH CLOUDS OVER THE ROCKIES TO FILTER OVER CWA.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 235 AM MST THU NOV 27 2014
FOR THE SHORT TERM PERIOD...MODELS HAVE BROAD UPPER RIDGE OVER THE
WESTERN PORTION OF THE COUNTRY TODAY...WITH A MID-LEVEL TROUGH OVER
THE EASTERN HALF. GOING INTO THE UPCOMING WEEKEND...UPPER FLOW
SET TO BECOME MORE ZONAL AS TROUGH BEGINS TO DIG SOUTH INTO THE
PACIFIC NORTHWEST. FOR TODAY THOUGH...SHORTWAVE IS EXPECTED TO
WORK THRU THE UPPER RIDGE AND BRING MID/HIGHS CLOUDS TO THE AREA
BEFORE CLEARING OUT. WITH ZONAL FLOW DEVELOPING BY THE START OF
THE WEEKEND...THIS IS EXPECTED TO BE COMPLIMENTED BY A SURFACE
LEE-SIDE TROUGH OVER THE EAST SIDE OF THE ROCKIES...AIDING TO
PROVIDE A STRONGER WAA UNDER SSW FLOW FRIDAY RIGHT INTO SATURDAY
NIGHT. WITH STRONG RIDGING OVER THE AREA...MODEL 850/925 TEMPS
WILL RANGE FROM +14C TODAY...UP TO +20C BY FRIDAY...BEFORE
TAPERING BACK DOWN BY LATE IN THE WEEKEND. OVERALL...THE CWA WILL
SEE GOOD CHANCE FOR 70S FOR HIGHS TODAY INTO SATURDAY ESPECIALLY
FOR WESTERN ZONES. THIS IS GOING TO SET THE AREA FOR 10-15 DEGREES
ABOVE NORMAL FOR HIGHS AND SEVERAL DEGREES ABOVE CURRENT TRENDS
FOR OVERNIGHT LOWS. NO PRECIP IS EXPECTED TO AFFECT THE TRI STATE
REGION THRU SATURDAY NIGHT...ALTHOUGH A FRONT MOVING SOUTHWARD
LATE SUNDAY WILL WORK INTO THE REGION.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 235 AM MST THU NOV 27 2014
SUNDAY THROUGH WEDNESDAY WILL START OUT WITH A STRONG COLD FRONT
MOVING THROUGH THE AREA ON SUNDAY MORNING. BEHIND THE FRONT WELL
BELOW NORMAL TEMPERATURES WILL MOVE INTO THE AREA. AM NOT EXPECTING
ANY PRECIPITATION WITH THE FRONTAL PASSAGE DUE TO THE 1000-500MB
MOISTURE AND MAIN UPPER LEVEL TROUGH REMAINING OVER THE NORTHERN
PLAINS. WIND CHILLS WILL DROP TO AROUND ZERO SUNDAY NIGHT AS THE
COLD AIR MASS SETTLES OVER THE AREA.
A SECOND LESS INTENSE COLD FROM WILL MOVE THROUGH THE AREA TUESDAY
NIGHT. THERE IS SOME UNCERTAINTY ABOUT PRECIPITATION DEVELOPMENT
ASSOCIATED WITH THE UPPER LEVEL TROUGH MOVING OFF THE WEST COAST
BEHIND THE FRONT FROM TUESDAY NIGHT. MODELS DISAGREE HOW FAST THE
UPPER LEVEL TROUGH WILL MOVE THROUGH...WITH THE SLOWER ONE HAVING
DRY NORTHWEST FLOW OVER THE AREA DUE TO THE TROUGH STILL OUT TO SEA.
THE FASTER OTHER MODEL HAS MOIST WEST FLOW OVER THE AREA AS THE
TROUGH MOVES THROUGH. AT THIS POINT WILL NOT DEVIATE FROM WHAT THE
INITIAL MODEL BLEND GAVE WHICH HAS LOW PRECIP. CHANCES IN FOR
VARIOUS PARTS OF THE AREA WEDNESDAY NIGHT THROUGH THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 429 AM MST THU NOV 27 2014
VFR CONDITIONS EXPECTED THRU FORECAST PERIOD W/ FEW-SCT060-070
SCT150. WINDS SSE 5-10KTS BECM WSW BY 16Z THIS MORNING...THEN MORE
WESTERLY AFTER 00Z FRIDAY 5-10KTS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...RRH
SHORT TERM...JN
LONG TERM...JTL
AVIATION...JN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1240 PM EST THU NOV 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 556 AM EST THU NOV 27 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS REVEAL AN AMPLIFIED PATTERN
ACROSS NAMERICA WITH A RIDGE OVER THE W COAST AND A TROF EXTENDING
FROM NCNTRL CANADA INTO THE ERN CONUS. A SHORTWAVE TROF MOVING
ACROSS THE REGION IS PRODUCING SOME -SN OVER NCNTRL WI AND PERHAPS
PROVIDING SOME ENHANCEMENT TO LES OVER ERN LAKE SUPERIOR INTO THE
THE ERN HALF OF UPPER MI. COLD AND VERY DRY AIR MASS UPSTREAM AS
NOTED ON 00Z KINL SNDG AND MINUS TEENS TO MINUS 20S DEWPOINTS OVER
WRN ONTARIO AND NRN MN WILL NEGATIVELY IMPACT LES FROM WEST TO EAST
TODAY AS IT MOVES ACROSS LAKE SUPERIOR IN THE WAKE OF THE SHORTWAVE
PASSAGE.
TODAY...MODEL SNDGS SHOW SHARP LOWERING OF INVERSION BASES BLO 4KFT
AS Q-VECT DIV SPREADING FROM WEST TO EAST ACROSS THE FCST AREA TODAY
AHEAD OF ADVANCING SHORTWAVE RIDGE. LOW-LEVEL FLOW ALSO BCMS MORE
ANTICYCLONIC THROUGH THE DAY WHICH IN TURN WILL WEAKEN LOW-LVL
CONVERGENCE. ALL THESE FACTORS WILL COMBINE TO QUICKLY DIMINISH LES
FROM W TO E THRU THE DAY. IN FACT OVER THE FAR W...EXPECT LES TO END
LATE IN THE AFTN AROUND KIWD AS FLOW BACKS SW. THE ONE POSITIVE
FACTOR FOR THE LES S THAT THE DGZ IS FIRMLY SITUATED THROUGH THE
CONVECTIVE LAYER ALLOWING FOR FLUFFY SNOW ACCUMULATIONS.
SO...DESPITE THE NEGATIVES LEADING TO MOSTLY LIGHT LES ON THE
WHOLE...MIGHT BE ABLE TO STILL GET 3-4 INCHES OF ADDITIONAL SNOW
WHERE LES IS MOST PERSISTENT. THE GREATEST ACCUMULATIONS WILL OCCUR
E OF MARQUETTE WHERE LOW-LEVEL FLOW IS MORE CYCLONIC THRU THE EARLY
PART OF THE DAY AND WHERE NW FETCH MAY BE HELPED BY LAKE NIPIGON
PRECONDITIONING. AWAY FROM THE MAIN LES...SCT -SHSN/FLURRIES ARE
POSSIBLE AT TIMES...EXCEPT OVER THE FAR SCNTRL. TEMPS WILL BE
UNSEASONABLY COLD TODAY AS 850MB THERMAL TROF (AROUND -20C) PASSES
ACROSS THE AREA. EXPECT HIGHS RANGING FM 10 TO 15F OVER THE WEST
HALF...TO AROUND 20F ALONG LAKE SUPERIOR AND E. RECORD LOW MAX
TEMP OF 18F HERE AT NWS MQT WILL FALL. IF TEMP DOESN`T REACH
14F...IT WILL BE THE COLDEST MAX TEMP FOR SO EARLY IN THE SEASON.
TONIGHT...THE LINGERING LES WILL DIMINISH OVER THE KEWEENAW AND FAR
ERN SHORELINE PORTION OF CWA AS THE SFC RIDGE AXIS SLIDES THROUGH
THE AREA ALLOWING THE LOW LEVEL WINDS TO BACK SW. WITH LIGHT
WINDS AND A PERIOD OF CLEARING OVER THE INTERIOR WEST DURING THE
EVENING...TEMPS WILL DROP QUICKLY TO MINS ON THE LOWER END OF MODEL
GUIDANCE BEFORE RECOVERING OVERNIGHT AS CLOUDS MOVE IN. MODELS
TRENDING A BIT SLOWER WITH ARRIVAL OF LIGHT SNOW INTO THE WEST LATE
WITH THE DEVELOPING WAA PATTERN...SO HAVE TRIMMED BACK POPS TO
SLIGHT CHC.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 509 AM EST THU NOV 27 2014
TROUGHING BRINGING THE WELL BLO NORMAL TEMPERATURES ACROSS THE AREA
TODAY EXITS OVER EASTERN CANADA AND NEW ENGLAND ON FRIDAY. UPPER
LEVEL FLOW BECOMES MORE PROGRESSIVE FROM THE PACIFIC NW ACROSS THE
NORTHERN PLAINS AND OVER THE GREAT LAKES REGION. SHORTWAVE TROUGH
CURRENTLY JUST OFFSHORE OF PACIFIC NW HEADS EAST AND WILL SUPPORT
AREA OF WARM ADVECTION/ISENTROPIC ASCENT ALONG TIGHT BAROCLINIC ZONE
SFC-H85. MODELS STILL DIFFER ON WHERE SHARPEST TEMPERATURE GRADIENT
SETS UP...BUT SEEMS THAT AT LEAST THE SOUTH HALF OF UPR MICHIGAN
SEES WIDESPREAD SNOW...WITH A BIT MORE QUESTION ON NORTHERN EXTENT.
IF BAND OF MORE CONCENTRATED SNOW SLIDES NORTHWARD THEN COULD SEE
AMOUNTS NEARING ADVY ALONG THE WI BORDER AND NEAR BAY OF GREEN BAY
FRIDAY AFTN INTO FRIDAY EVENING. PRIMARY AREA OF CONCERN STILL IS OVER
EASTERN CWA THOUGH...SCHOOLCRAFT AND LUCE COUNTIES...DUE TO LAKE
ENHANCEMENT OFF LK MICHIGAN AS THE LARGER SCALE MOISTURE AND FORCING
WITH THE SHORTWAVE COMBINES WITH MEAN BLRY SSW FLOW AND H85 TEMPS
LOWER THAN -10C...PLENTY LOW ENOUGH FOR LAKE ENHANCEMENT WITH LK
MICHIGAN WATER TEMPS AROUND UP TO 4C. IF THE FARTHER NORTH NAM IDEA
IS CORRECT WITH MORE DIRECT INFLUENCE FROM THE INCOMING SYSTEM...THEN
MODERATE TO HEAVY SNOW WOULD OCCUR. BLEND OF OTHER MODELS...INCLUDING
THE FAVORED ECMWF/GEM-NH...POINT TO SOLID ADVY AMOUNTS. WILL MENTION
IN THE HWO AND HIGHLIGHT IN EHWO GRAPHICS...BUT NOT ISSUE ANY WATCH
ATTM GIVEN THE UNCERTAINTY ON TRACK OF INCOMING SYSTEM.
MESSY FORECAST LATER FRIDAY NIGHT INTO SATURDAY. OR MAYBE IT WILL
JUST END UP BENIGN. STILL TRYING TO FIGURE THIS OUT...BUT ECMWF/GEM
AND TREND FROM GFS WOULD SUGGEST MORE DRIER IDEA. ECMWF AND GEM ARE
FARTHER NORTH WITH LARGER SCALE Q-VECTOR CONVERGENCE AND DEEP
MOISTURE TIED INTO THE NEXT SHORTWAVE/SFC LOW MOVING ACROSS IN WHAT
LOOKS MORE LIKE A ZONAL FLOW PATTERN. H85 TEMPS QUITE WARM OFF THE
ECMWF WITH +8C...YES PLUS 8...INTO SCNTRL UPR MICHIGAN BY 00Z
SUNDAY. GEM EVEN WARMER AND THE NAM/GFS IN THE BALLPARK AS WELL.
EVEN WITH THE WARMTH...SOUNDINGS FM THE NAM/GFS SUGGEST THE ONLY
KIND OF PRECIP OCCURRING...IF ANY...WOULD BE DRIZZLE AS ONLY MOISTURE
IS BLO H85 WITH DRY AIR ALOFT. EXCEPTION TO THIS WOULD BE OVER THE
NORTH AND EAST CWA SATURDAY MORNING AND THEN RETURNING TO THE
NORTHWEST CWA LATER SATURDAY NIGHT ONCE THE SFC LOW PASSES BY AND A
COLD FRONT RE-ENTERS THE PICTURE. HAVE TRENDED TOWARD THE DZ/FZDZ
IDEA FOR LATE FRIDAY NIGHT THROUGH SATURDAY. NOW IF THIS FORECAST OF
LOW LEVEL MOISTURE TRAPPED BENEATH THE WARM AIR ADVECTION ALOFT TURNS
OUT TO BE OVERDONE AS HAS OCCURRED IN THE PAST...THEN SATURDAY COULD
ACTUALLY END UP BEING AN NICE DAY WITH PARTLY SUNNY SKIES AND ABOVE
NORMAL TEMPS. MIXING TO H9 VALUES OFF THE GFS WOULD YIELD LOW 40S
OVER PARTS OF THE AREA. FOR NOW...KEPT WITH THE LOW CLOUD/DZ IDEA AND
HAVE HIGHS IN THE MID 30S.
ONCE THE COLD FRONT ARRIVES LATER SATURDAY NIGHT...PRETTY QUICK DROP
OFF IN TEMPS AT H85. ECMWF SLOWER THAN THE GFS AND PROBABLY IS MORE
ON TRACK GIVEN THE FARTHER NORTH TREND OF WARMER AIR TO START THE
WEEKEND. EVEN SO...ENOUGH COLD AIR BY SUNDAY AFTN TO START THE LAKE
EFFECT UP AGAIN FOR AREAS FAVORED BY NORTHWEST WINDS. SHORTWAVE MOVING
THROUGH SUNDAY INTO MONDAY COULD RESULT IN A PERIOD OR TWO OF LAKE
ENHANCEMENT. CORE OF COLDEST AIR ARRIVES ON MONDAY. H85 TEMPS A VERY
CHILLY -20C TO -24C...COLDEST ON THE GFS. AT LEAST LIGHT LES SHOULD
CONTINUE NEAR LK SUPERIOR AND EAST. CENTER OF HIGH PRESSURE RIDGE IS
MORE OVER THE PLAINS...SO PRESSURE GRADIENT WILL BE FAIRLY TIGHT
LEADING TO SOME LOWER WIND CHILLS ON MONDAY MORNING.
ONCE THE HIGH MOVES TOWARD THE LOWER GREAT LAKES ON TUESDAY...TEMPS
MODERATE IN WARM AIR ADVECTION ON THE BACK SIDE OF THE HIGH. COULD
BE SOME SNOW BREAK OUT OVER REGION DUE TO THE WARM AND MOIST ADVECTION.
BEST CHANCE OF THAT LOOKS TO BE NEXT TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1240 PM EST THU NOV 27 2014
EXPECT IMPROVING CONDITIONS THIS AFTERNOON INTO TONIGHT AT IWD AND
CMX AS LES DIMINISHES DUE TO INCOMING DRY AIR. SAW SHOULD SEE CIGS
DEVELOP OVER THE NEXT COUPLE OF HOURS AS SCT CLOUDS BECOME BROKEN
DUE TO DAYTIME MIXING.
ALL SITES WILL SEE DIMINISHING CONDITIONS LATE TONIGHT INTO FRI AS A
CLIPPER SHORTWAVE SYSTEM MOVES SOUTH OF THE AREA...BRINGING SNOW AT
ALL SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 556 AM EST THU NOV 27 2014
NW WINDS TO 25 KNOTS WILL DIMINISH TO UNDER 20 KT W TO E TODAY INTO
TONIGHT AS HIGH PRES RIDGE ARRIVES. WITH ANOTHER COLD FRONT
PUSHING ACROSS THE UPPER LAKES SAT NIGHT...EXPECT INCREASING S/SW
WINDS TO 15-25KT FRI BEHIND THE FRONT...NW WINDS MAY REACH 20-30KT
LATE SAT NIGHT AND SUN AND INCREASE TO GALES BY SUN NIGHT INTO MON.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
MIZ006.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...TITUS
MARINE...VOSS
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1131 AM CST Thu Nov 27 2014
.SHORT TERM: (Today through Saturday)
Issued at 356 AM CST Thu Nov 27 2014
Clipper system is now well southeast of the CWFA, and only a few
lingering flurries remain. Expect any lingering precip to end by
12Z this morning and for the rest of the day to be cold and dry.
Some uncertainty on sky condition today as stratus over Iowa is
clearing fairly slowly from northwest to southeast. Short range NAM
and RAP 925mb RH field has a decent handle on the clouds at this
time, so have used a combination of these guidance products and
satellite observations to try and time gradual clearing today.
Canadian airmass over eastern Dakotas at this time will drift
southeast today and will provide the area with unseasonably cold
air. Cannot argue with MOS high temps in the mid-upper 20s to mid
30s across the area due to this cold high pressure system`s
influence.
Models continue to advertise a general pattern shift Friday into the
weekend with mid-upper level flow becoming more zonal. This will
allow warmer air to flow back into the area as the storm track
shifts north. Temperatures will moderate on Friday as the flow
shifts to the south-southwest on the western side of the Canadian
high which will have settled in over the Eastern CONUS. Expect
temperatures on Friday to be at least 10 to 15 degrees warmer than
today. Boundary layer moisture will also be on the increase, and
low level RH progs for Friday night/Saturday morning are showing
very moist conditions across the area by 12Z Saturday from about
900mb down to the surface. Have therefore increased cloud cover on
Saturday morning with some gradual clearing during the afternoon.
Models continue to spit out light QPF Saturday, but am still
skeptical due to the models` tendency to develop precipitation in
strong moisture return situations even with lifting mechanisms
aren`t present. Indeed, in this case model soundings are showing a
strong subsidence inversion in the low levels and positive values of
omega in the moist layer which would tend to lend credence to a dry
(tho cloudy/mostly cloudy) forecast for Saturday. Am still sticking
with above normal temperatures Saturday, though due to expected
cloud cover have backed off a little bit from warmest MOS guidance.
Carney
.LONG TERM: (Sunday through Wednesday)
Issued at 423 AM CST Thu Nov 27 2014
Sunday continues to look pretty mild over the majority of the area,
with the possible exception of northeast Missouri and west central
Illinois. Timing differences between the faster GFS and slower
ECMWF could mean the difference between a chilly day up north and a
day with highs between 10 and 15 degrees above normal. Leaned
toward the warmer solution this morning since the upstream shortwave
which will drive the front south is well back over Montana in the
ECMWF, and the GFS solution keeps the teeth of the shortwave up
north across the Upper Midwest. Would like to point out that this
could easily be wrong.
Cold front should be through the area by Monday morning according to
both the ECMWF and GFS with a 1040mb high building into the
Midwest. Confidence in the extended forecast beyond Monday is
pretty low as there seems to be little agreement between the GFS and
ECMWF. GFS hangs on to quasi-zonal flow aloft through Wednesday
which is mild and potentially a little wet. ECMWF develops a
full-latitude longwave trof over the eastern 1/2 of the CONUS which
would be drier and colder. Stuck with the ensemble blend of
guidance which tended toward a warmer and wetter solution for this
forecast cycle.
Carney
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1123 AM CST Thu Nov 27 2014
MVFR ceilings should move east of all TAF sites by around 22Z. VFR
cloud deck near 7000 feet then approaches from the west this
evening. Northwest winds will diminish rapidly this afternoon and
become light and variable overnight as surface ridge moves
overhead. Quick return to southeasterly flow on Friday with VFR
conditions expected.
Specifics for KSTL: MVFR ceilings should clear KSTL TAF site by
around 22Z. An area of VFR ceilings will move in after 00Z. Northwest
winds will diminish this evening. As surface high pressure moves
quickly off to the east, southeast winds will return by around
14Z.
Browning
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 32 25 49 39 / 0 0 0 0
Quincy 27 19 44 36 / 0 0 0 0
Columbia 32 25 53 41 / 0 0 0 0
Jefferson City 34 25 55 41 / 0 0 0 0
Salem 30 22 45 37 / 5 0 0 5
Farmington 35 23 48 39 / 0 0 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS RALEIGH NC
251 PM EST THU NOV 27 2014
.SYNOPSIS...AN UPPER LEVEL DISTURBANCE OVER THE REGION WILL SHIFT
EAST AND AWAY FROM THE AREA THIS EVENING. HIGH PRESSURE WILL BUILD
OVER THE REGION FROM THE WEST TONIGHT THROUGH EARLY SATURDAY...
BEFORE PUSHING EAST OFF THE COAST LATE SATURDAY THROUGH SUNDAY.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 215 PM THURSDAY...
THROUGH TONIGHT: THE NORTHERN TWO-THIRDS OF THE CENTRAL NC HAVE HAD
A VARIABLY CLOUDY... SOMEWHAT CHILLY... AND OCCASIONALLY SHOWERY
THANKSGIVING DAY SO FAR... THANKS TO PASSAGE OF A COUPLE OF
SHORTWAVE TROUGHS... THE SECOND OF WHICH IS NOW TRACKING EASTWARD
INTO THE WRN CAROLINAS. MESOANALYSES AND RAP SOUNDINGS SHOW MINOR
AMOUNTS OF CAPE... DUE TO FAIRLY STEEP 850-500 MB LAPSE RATES OF 6.5-
7.5 C/KM... AUGMENTING THE DYNAMIC FORCING FOR ASCENT. WILL MAINTAIN
SCATTERED SHOWERS OVER THE AREA FOR ANOTHER FEW HOURS... ENDING LAST
IN THE NE CWA BY VERY EARLY EVENING. AS THE SHORTWAVE TROUGH HEADS
TO OUR EAST... A DRYING AND STABILIZING COLUMN WILL ENSUE FROM WEST
TO EAST... YIELDING CLEARING SKIES AREAWIDE DURING THE EARLY-MID
EVENING. CLEAR SKIES AND DIMINISHING WINDS ARE EXPECTED OVERNIGHT
WITH RISING HEIGHTS... DOWNSLOPE-DIRECTED LOW LEVEL FLOW... AND HIGH
PRESSURE BEGINNING TO BUILD IN FROM THE WEST. BASED ON LOCAL
RESEARCH USING HISTORIC MIN TEMPS... LOW LEVEL THICKNESSES DROPPING
TO AROUND 1280 M WOULD SUGGEST LOWS IN THE LOWER 20S... HOWEVER WITH
THE MSLP GRADIENT STAYING UP ENOUGH TO ALLOW FOR A SLIGHT NW BREEZE
OVERNIGHT LIMITING RADIATIONAL COOLING SOMEWHAT... WILL STICK WITH
LOWS IN THE MID-UPPER 20S... CONSISTENT WITH STATISTICAL GUIDANCE.
FOR FRI/FRI NIGHT: A QUIET DAY AND NIGHT WITH HIGH PRESSURE BUILDING
OVERHEAD AND STRONGLY SUBSIDING MID LEVELS. EXPECT LOTS OF SUNSHINE
DURING THE DAY. THE THERMAL TROUGH LIFTS OUT DURING THE LATTER HALF
OF THE DAY... AND THICKNESSES ACCORDINGLY REBOUND CONSIDERABLY
(ALTHOUGH THIS 1000-850 MB LAYER GRABS SOME OF THE WARMER AIR ABOVE
THE SUBSIDENCE INVERSION). USING A LOW LEVEL DRY ADIABATIC PROFILE
TO 925 MB INDICATES HIGHS OF 42-46... A SLIGHT LEAN TO THE COOL SIDE
OF GUIDANCE AND IN LINE WITH EARLIER FORECAST HIGHS. THE SURFACE
RIDGE SHOULD BE OVERHEAD EARLY FRI NIGHT BUT SHIFTING EASTWARD
LATE... SO WINDS SHOULD BE FAIRLY LIGHT WITH GENERALLY CLEAR
SKIES... ALTHOUGH WE`LL SEE INCREASING HIGH CLOUDS LATE AS MINOR
WAVES TRACK ESE INTO NC WITHIN THE FAST STEERING FLOW ALOFT. STILL
EXPECT LOWS IN THE MID-UPPER 20S. -GIH
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 245 PM THURSDAY...
HIGH PRESSURE WILL SHIFT OFFSHORE DURING THE DAY ON SATURDAY...
ALLOWING RETURN FLOW TO FIRMLY SET UP OVER THE REGION FOR THE
WEEKEND. IN ADDITION...MID LEVEL RIDGING WILL BUILD NORTH AND EAST
ACROSS THE AREA. ALL OF THIS WILL LEAD TO FAIR WEATHER AND A WARMING
TREND...WITH HIGHS EXPECTED TO BE IN THE LOW TO MID 50S ON SATURDAY
AND THEN LOW TO MID 60S BY SUNDAY. OVERNIGHT LOWS WILL ALSO MODERATE
THROUGH THE PERIOD...WITH MOSTLY MID/UPPER 30S SATURDAY NIGHT AND
THEN MID/UPPER 40S SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...
A NORTHERN STREAM SHORT WAVE MOVING ALONG THE US/CANADIAN BORDER
WILL SUPPRESS THE MID LEVEL RIDGE TO THE SOUTH AS IT PROPELS A
SURFACE FRONT TOWARDS THE REGION EARLY NEXT WEEK. THIS TRAILING COLD
FRONT IS STILL PROGGED TO CROSS THE AREA MONDAY NIGHT INTO TUESDAY.
FORCING IS NOT THAT IMPRESSIVE WITH THIS SYSTEM GIVEN THE PARENT LOW
IS SO FAR NORTH OF THE AREA. HOWEVER...GIVEN SOME CONVERGENCE AND
MOISTURE POOLING ALONG THE BOUNDARY...WILL MAINTAIN SLIGHT CHANCE
POPS IN THE FORECAST. HIGHS WILL WARM UP NICELY WITHIN THE DEEP
SOUTHWESTERLY FLOW AHEAD OF THE FRONT...WITH MID TO UPPER 60S (NEAR
70 DEGREES ACROSS THE SOUTHEAST) EXPECTED. TEMPS WILL BE COOLER
BEHIND THE FRONT ON TUESDAY...WITH HIGHS GENERALLY IN THE UPPER 40S
TO MID/UPPER 50S (COOLEST IN THE NORTHWEST WHERE SOME CAD MAY
DEVELOP).
QUITE A BIT OF UNCERTAINTY THEN PERSISTS FOR THE REMAINDER OF THE
FORECAST PERIOD AS ANOTHER SYSTEM (POSSIBLY) APPROACHES FROM THE
NORTHWEST. THE ECMWF IS MUCH MORE AMPLIFIED/PROGRESSIVE WITH ANOTHER
SHORT WAVE SWINGING THROUGH THE AREA WEDNESDAY INTO THURSDAY...WILL
THE GFS IS MUCH LESS AMPLIFIED (WITH ZONAL FLOW ACTUALLY OVER THE
MID ATLANTIC REGION). GIVEN THE DIFFERENCES...WILL KEEP ANY POPS
LOW...WITH SEASONAL HIGHS/LOWS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 1250 PM THURSDAY...
PRIMARY AVIATION CONCERNS THIS CYCLE: LOW CLOUDS AT NORTHERN
TERMINALS THROUGH 22Z. A COUPLE OF UPPER LEVEL DISTURBANCES CROSSING
NRN NC TODAY HAVE LED TO CONSIDERABLE SUB-VFR CLOUDS OVER THE
NORTHERN TERMINALS (INT/GSO/RDU/RWI) SO FAR TODAY. CIGS HAVE
IMPROVED A BIT TO MVFR AS THE SHOWERS HAVE BECOME A LITTLE MORE
PATCHY... AND EVEN IN SHOWERS... VSBYS HAVE HELD MOSTLY VFR. AS THE
DISTURBANCE SHIFTS EASTWARD LATE THIS AFTERNOON... CIGS WILL
STEADILY IMPROVE TO VFR... FIRST AT INT (WHERE THE MVFR CLOUDS HAVE
ALREADY BEGUN TO BREAK UP TO SCATTERED) AND GSO BY 21Z... AND ACROSS
TO RDU/RWI BY 00Z-01Z. SURFACE WINDS FROM THE NORTHWEST SUSTAINED AT
8-12 KTS HAVE HAD INFREQUENT GUSTS TO 15-20 KTS... AND THESE SHOULD
DIMINISH BY EVENING AS THE DISTURBANCE EXITS. CLEARING THIS EVENING
WILL YIELD UNLIMITED CIGS AND VSBYS AT ALL SITES AFTER 03Z. HIGH
CONFIDENCE IN VFR CONDITIONS WITH MOSTLY CLEAR SKIES AND LIGHT WINDS
THROUGH FRI... AS HIGH PRESSURE BUILDS IN FROM THE WEST.
LOOKING BEYOND 18Z FRI... VFR CONDITIONS ARE EXPECTED TO DOMINATE
THROUGH MON... ALTHOUGH AREAS OF MVFR OR IFR FOG ARE POSSIBLE EARLY
SUN MORNING AND EARLY MON MORNING. HIGH PRESSURE WILL SHIFT EASTWARD
OVER THE REGION THROUGH SAT... THEN MOVE EAST AND OFFSHORE SAT
NIGHT/SUN. A COLD FRONT WILL MOVE IN FROM THE NORTH LATE MON OR MON
NIGHT... BRINGING A GOOD CHANCE OF MVFR/IFR CONDITIONS MON NIGHT/TUE
AND PATCHY LIGHT RAIN. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...KRD
LONG TERM...KRD
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
215 PM EST THU NOV 27 2014
.SYNOPSIS...AN UPPER LEVEL DISTURBANCE OVER THE REGION WILL SHIFT
EAST AND AWAY FROM THE AREA THIS EVENING. HIGH PRESSURE WILL BUILD
OVER THE REGION FROM THE WEST TONIGHT THROUGH EARLY SATURDAY...
BEFORE PUSHING EAST OFF THE COAST LATE SATURDAY THROUGH SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 215 PM THURSDAY...
THROUGH TONIGHT: THE NORTHERN TWO-THIRDS OF THE CENTRAL NC HAVE HAD
A VARIABLY CLOUDY... SOMEWHAT CHILLY... AND OCCASIONALLY SHOWERY
THANKSGIVING DAY SO FAR... THANKS TO PASSAGE OF A COUPLE OF
SHORTWAVE TROUGHS... THE SECOND OF WHICH IS NOW TRACKING EASTWARD
INTO THE WRN CAROLINAS. MESOANALYSES AND RAP SOUNDINGS SHOW MINOR
AMOUNTS OF CAPE... DUE TO FAIRLY STEEP 850-500 MB LAPSE RATES OF 6.5-
7.5 C/KM... AUGMENTING THE DYNAMIC FORCING FOR ASCENT. WILL MAINTAIN
SCATTERED SHOWERS OVER THE AREA FOR ANOTHER FEW HOURS... ENDING LAST
IN THE NE CWA BY VERY EARLY EVENING. AS THE SHORTWAVE TROUGH HEADS
TO OUR EAST... A DRYING AND STABILIZING COLUMN WILL ENSUE FROM WEST
TO EAST... YIELDING CLEARING SKIES AREAWIDE DURING THE EARLY-MID
EVENING. CLEAR SKIES AND DIMINISHING WINDS ARE EXPECTED OVERNIGHT
WITH RISING HEIGHTS... DOWNSLOPE-DIRECTED LOW LEVEL FLOW... AND HIGH
PRESSURE BEGINNING TO BUILD IN FROM THE WEST. BASED ON LOCAL
RESEARCH USING HISTORIC MIN TEMPS... LOW LEVEL THICKNESSES DROPPING
TO AROUND 1280 M WOULD SUGGEST LOWS IN THE LOWER 20S... HOWEVER WITH
THE MSLP GRADIENT STAYING UP ENOUGH TO ALLOW FOR A SLIGHT NW BREEZE
OVERNIGHT LIMITING RADIATIONAL COOLING SOMEWHAT... WILL STICK WITH
LOWS IN THE MID-UPPER 20S... CONSISTENT WITH STATISTICAL GUIDANCE.
FOR FRI/FRI NIGHT: A QUIET DAY AND NIGHT WITH HIGH PRESSURE BUILDING
OVERHEAD AND STRONGLY SUBSIDING MID LEVELS. EXPECT LOTS OF SUNSHINE
DURING THE DAY. THE THERMAL TROUGH LIFTS OUT DURING THE LATTER HALF
OF THE DAY... AND THICKNESSES ACCORDINGLY REBOUND CONSIDERABLY
(ALTHOUGH THIS 1000-850 MB LAYER GRABS SOME OF THE WARMER AIR ABOVE
THE SUBSIDENCE INVERSION). USING A LOW LEVEL DRY ADIABATIC PROFILE
TO 925 MB INDICATES HIGHS OF 42-46... A SLIGHT LEAN TO THE COOL SIDE
OF GUIDANCE AND IN LINE WITH EARLIER FORECAST HIGHS. THE SURFACE
RIDGE SHOULD BE OVERHEAD EARLY FRI NIGHT BUT SHIFTING EASTWARD
LATE... SO WINDS SHOULD BE FAIRLY LIGHT WITH GENERALLY CLEAR
SKIES... ALTHOUGH WE`LL SEE INCREASING HIGH CLOUDS LATE AS MINOR
WAVES TRACK ESE INTO NC WITHIN THE FAST STEERING FLOW ALOFT. STILL
EXPECT LOWS IN THE MID-UPPER 20S. -GIH
&&
.SHORT TERM /FRIDAY NIGHT/...
AS OF 305 AM THURSDAY...
FRIDAY NIGHT: SURFACE HIGH PRESSURE WILL SETTLE OVER THE REGION ON
FRIDAY NIGHT. MEANWHILE... MID LEVEL FLOW WILL REMAIN OUT OF THE WNW
WITH THE POTENTIAL FOR A FEW WEAK DISTURBANCES TO MOVE ACROSS THE
MID ATLANTIC REGION. HOWEVER... WE WILL REMAIN DRY WITH ONLY AN
INCREASE IN SOME HIGH CLOUDS ON SATURDAY MORNING. STILL THINK THE
CLOUDS WILL BE THIN ENOUGH NOT TO HAVE A SIGNIFICANT IMPACT ON LOW
TEMPS. GIVEN THIS... THINK WE SHOULD SEE TEMPS PLUMMET INTO THE 20S
ACROSS THE ENTIRE AREA... WITH LOWS IN THE MID TO UPPER 20S (MAYBE
EVEN A FEW LOWER 20S IN THE USUAL RURAL COLD SPOTS DEPENDING ON THE
CLOUD COVER). -BSD
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 310 AM THURSDAY...
HIGH PRESSURE WILL SHIFT TO THE SOUTH AND EAST OF CENTRAL NC THIS
WEEKEND ALLOWING FOR A WARMING TREND. HIGH TEMPS ARE EXPECTED TO BE
IN THE LOWER TO MID 50S FOR SATURDAY AND LOWER TO MID 60S FOR
SUNDAY. MID LEVEL RIDGING IS FORECAST TO BUILD NORTHWARD DURING THIS
TIME FRAME AND NUDGE INTO OUR AREA. HOWEVER... AS A NORTHERN STEAM
TROUGH IS FORECAST TO TRACK NEAR THE U.S./CANADIAN (EAST COAST THAT
IS) BORDER DURING THIS TIME FRAME A TRAILING COLD FRONT WILL DROP
SOUTHWARD AND INTO CENTRAL NC EARLY NEXT WEEK. MODEL GUIDANCE HAS
TRENDED TOWARDS THE SURFACE FRONT MOVING INTO THE AREA ON MONDAY
NIGHT INTO EARLY TUESDAY MORNING... PUSHED BY A 1035-1040 MB SURFACE
HIGH TO THE NORTH/NORTHWEST. THIS SHOULD ALLOW FOR ONE LAST WARM DAY
ON MONDAY... WITH HIGHS IN THE 60S TO LOWER 70S SOUTH.
GIVEN THE LAST SEVERAL DAYS MEDIUM RANGE MODELS HAVE TRENDED WETTER
WITH THE AFOREMENTIONED FRONT AND THE POTENTIAL FOR AT LEAST SOME
HYBRID COLD AIR DAMMING FOR MONDAY NIGHT INTO TUESDAY. HOWEVER...
WPC STILL PREFERS TO KEEP POPS LOW WITH THE ARRIVAL OF THE FRONT
GIVEN THE APPARENT SPREAD IN GUIDANCE/ENSEMBLES GUIDANCE OVER THE PAST
FEW DAYS AND DIFFERENCES WITH THE OPERATIONAL MODELS VS THEIR
ENSEMBLES. THUS... FOR NOW PREFER TO KEEP POPS AT SLIGHT CHANCE FOR
MONDAY NIGHT INTO TUESDAY AND TREND TEMPS DOWNWARD. FOR WEDNESDAY...
WE MAY HAVE SOME FORM OF LINGERING CAD ACROSS THE AREA. HOWEVER...
THE PARENT SURFACE HIGH SHOULD BE WELL OFF THE NORTHEAST U.S. COAST
BY THIS TIME. THE NEXT SYSTEM WILL QUICKLY APPROACH FROM THE
NORTHWEST. HOWEVER... THERE IS A LARGE SPREAD AMONG THE GUIDANCE IN
TIMING OF THE FRONT. WPC HOLDS THE FRONT TO OUR NORTH DURING THIS
TIME FRAME... GOING WITH A LESS AMPLIFIED PATTERN. GIVEN THE LOWER
CONFIDENCE WILL KEEP TEMPS WITHIN A COUPLE CATEGORIES OF NORMAL AT
WORST... GIVEN THE LARGE POSSIBLE SPREAD IN TEMPS. THIS YIELDS HIGHS
ON TUESDAY IN THE UPPER 40S TO 50S... WITH HIGHS ON WEDNESDAY IN THE
50S TO SOME 60S... AND LOWS IN THE 30S AND 40S.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 1250 PM THURSDAY...
PRIMARY AVIATION CONCERNS THIS CYCLE: LOW CLOUDS AT NORTHERN
TERMINALS THROUGH 22Z. A COUPLE OF UPPER LEVEL DISTURBANCES CROSSING
NRN NC TODAY HAVE LED TO CONSIDERABLE SUB-VFR CLOUDS OVER THE
NORTHERN TERMINALS (INT/GSO/RDU/RWI) SO FAR TODAY. CIGS HAVE
IMPROVED A BIT TO MVFR AS THE SHOWERS HAVE BECOME A LITTLE MORE
PATCHY... AND EVEN IN SHOWERS... VSBYS HAVE HELD MOSTLY VFR. AS THE
DISTURBANCE SHIFTS EASTWARD LATE THIS AFTERNOON... CIGS WILL
STEADILY IMPROVE TO VFR... FIRST AT INT (WHERE THE MVFR CLOUDS HAVE
ALREADY BEGUN TO BREAK UP TO SCATTERED) AND GSO BY 21Z... AND ACROSS
TO RDU/RWI BY 00Z-01Z. SURFACE WINDS FROM THE NORTHWEST SUSTAINED AT
8-12 KTS HAVE HAD INFREQUENT GUSTS TO 15-20 KTS... AND THESE SHOULD
DIMINISH BY EVENING AS THE DISTURBANCE EXITS. CLEARING THIS EVENING
WILL YIELD UNLIMITED CIGS AND VSBYS AT ALL SITES AFTER 03Z. HIGH
CONFIDENCE IN VFR CONDITIONS WITH MOSTLY CLEAR SKIES AND LIGHT WINDS
THROUGH FRI... AS HIGH PRESSURE BUILDS IN FROM THE WEST.
LOOKING BEYOND 18Z FRI... VFR CONDITIONS ARE EXPECTED TO DOMINATE
THROUGH MON... ALTHOUGH AREAS OF MVFR OR IFR FOG ARE POSSIBLE EARLY
SUN MORNING AND EARLY MON MORNING. HIGH PRESSURE WILL SHIFT EASTWARD
OVER THE REGION THROUGH SAT... THEN MOVE EAST AND OFFSHORE SAT
NIGHT/SUN. A COLD FRONT WILL MOVE IN FROM THE NORTH LATE MON OR MON
NIGHT... BRINGING A GOOD CHANCE OF MVFR/IFR CONDITIONS MON NIGHT/TUE
AND PATCHY LIGHT RAIN. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD
SHORT TERM...BSD
LONG TERM...BSD
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1250 PM EST THU NOV 27 2014
.SYNOPSIS...AN UPPER LEVEL DISTURBANCE AND ASSOCIATED LOW PRESSURE
SYSTEM WILL TRACK EAST ACROSS THE REGION THROUGH THIS AFTERNOON.
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE WEST LATE TODAY
THROUGH TONIGHT... THEN SETTLE OVER THE CAROLINAS ON FRIDAY AND
SATURDAY... BEFORE PUSHING EAST OFF THE COAST SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1105 AM THURSDAY...
HAPPY THANKSGIVING!
FORECAST REQUIRED LITTLE CHANGE THIS MORNING. THE LEADING SHORTWAVE
TROUGH EVIDENT ON WATER VAPOR IMAGERY IS NOW WOBBLING ACROSS NORTH
CENTRAL NC... GENERATING NUMEROUS SHOWERS ACROSS THE NRN CWA. FAST
ON ITS HEELS IS THE SECOND WEAKER WAVE GENERATING SNOW SHOWERS ON
THE WEST SLOPES OF THE SOUTHERN APPALACHIANS... HOWEVER MUCH OF THIS
APPEARS TO BE DRYING UP AS THE PRECIP HEADS JUST EAST OF THE
MOUNTAINS WHERE THE LOW LEVEL FLOW HAS A NOTABLE DOWNSLOPE
COMPONENT. NEVERTHELESS... BOTH ON THE TAIL END OF THE LEADING WAVE
AND WITH THE SECOND WAVE AS IT SHIFTS EAST ACROSS THE STATE... WILL
NEED TO MONITOR FOR A FEW POCKETS OF MIXED RAIN AND WET SNOW OVER
THE EXTREME NNW CWA. IN FACT... KRAX DUAL POL PRODUCTS INDICATE THE
MELTING LEVEL AT AROUND 2200 FT... A BIT LOWER THAN RAP FORECAST
SOUNDINGS SUGGEST... SO WE COULD DEFINITELY SEE SOME WET FLAKES
WHERE PRECIP RATES ARE HIGHER. TEMPS RANGE FROM THE UPPER 30S TO
LOWER 40S NORTH TO THE UPPER 40S/NEAR 50 SOUTH... AND THE NORTHERN
HALF IS UNLIKELY TO SEE MUCH MORE THAN A ONE TO PERHAPS TWO CATEGORY
CLIMB FOR THE REST OF THE DAY... AND EVEN THEN ONLY IF WE CAN GET
ENOUGH SUNSHINE. THESE CHANCES DON`T LOOK TOO GOOD GIVEN THE
PERSISTENT MOISTURE IN THE LOW LEVELS NOTED ON UPPER AIR ANALYSES.
WILL ADJUST NORTHERN HIGHS DOWN JUST A TAD... TO RANGE FROM MID 40S
NORTH (AND AGAIN THIS MAY BE OPTIMISTIC) UNDER MOSTLY CLOUDY SKIES
TO MID 50S SOUTH (WHICH COULD BE PESSIMISTIC GIVEN THE FAIR SKIES
THERE). -GIH
TONIGHT...SKIES WILL CLEAR OFF FAIRLY QUICKLY WEST-TO EAST LATE THIS
AFTERNOON EARLY EVENING AS DRIER AIR OVERSPREADS THE REGION. COLD
AIR ADVECTION WILL KEEP THE NEAR SURFACE ATMOSPHERE WELL MIXED UNTIL
JUST PRIOR TO DAYBREAK. THE CAA WILL SEND TEMPS INTO THE MID-UPPER
20S BY EARLY FRIDAY.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 305 AM THURSDAY...
FRIDAY...CHILLY HIGH PRESSURE WILL BUILD INTO AND SETTLES OVERHEAD.
LOW LEVEL THICKNESSES AVERAGE 45M BELOW NORMAL...SUGGESTIVE OF MAX
TEMPS 10-14 DEGREES BELOW NORMAL. THIS YIELDS MAX TEMPS IN THE LOW-
MID 40S. SKIES WILL REMAIN MOSTLY CLEAR ASIDE FROM A FEW PASSING
CIRRUS IN THE AFTERNOON. -WSS
FRIDAY NIGHT: SURFACE HIGH PRESSURE WILL SETTLE OVER THE REGION ON
FRIDAY NIGHT. MEANWHILE... MID LEVEL FLOW WILL REMAIN OUT OF THE WNW
WITH THE POTENTIAL FOR A FEW WEAK DISTURBANCES TO MOVE ACROSS THE
MID ATLANTIC REGION. HOWEVER... WE WILL REMAIN DRY WITH ONLY AN
INCREASE IN SOME HIGH CLOUDS ON SATURDAY MORNING. STILL THINK THE
CLOUDS WILL BE THIN ENOUGH NOT TO HAVE A SIGNIFICANT IMPACT ON LOW
TEMPS. GIVEN THIS... THINK WE SHOULD SEE TEMPS PLUMMET INTO THE 20S
ACROSS THE ENTIRE AREA... WITH LOWS IN THE MID TO UPPER 20S (MAYBE
EVEN A FEW LOWER 20S IN THE USUAL RURAL COLD SPOTS DEPENDING ON THE
CLOUD COVER). -BSD
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 310 AM THURSDAY...
HIGH PRESSURE WILL SHIFT TO THE SOUTH AND EAST OF CENTRAL NC THIS
WEEKEND ALLOWING FOR A WARMING TREND. HIGH TEMPS ARE EXPECTED TO BE
IN THE LOWER TO MID 50S FOR SATURDAY AND LOWER TO MID 60S FOR
SUNDAY. MID LEVEL RIDGING IS FORECAST TO BUILD NORTHWARD DURING THIS
TIME FRAME AND NUDGE INTO OUR AREA. HOWEVER... AS A NORTHERN STEAM
TROUGH IS FORECAST TO TRACK NEAR THE U.S./CANADIAN (EAST COAST THAT
IS) BORDER DURING THIS TIME FRAME A TRAILING COLD FRONT WILL DROP
SOUTHWARD AND INTO CENTRAL NC EARLY NEXT WEEK. MODEL GUIDANCE HAS
TRENDED TOWARDS THE SURFACE FRONT MOVING INTO THE AREA ON MONDAY
NIGHT INTO EARLY TUESDAY MORNING... PUSHED BY A 1035-1040 MB SURFACE
HIGH TO THE NORTH/NORTHWEST. THIS SHOULD ALLOW FOR ONE LAST WARM DAY
ON MONDAY... WITH HIGHS IN THE 60S TO LOWER 70S SOUTH.
GIVEN THE LAST SEVERAL DAYS MEDIUM RANGE MODELS HAVE TRENDED WETTER
WITH THE AFOREMENTIONED FRONT AND THE POTENTIAL FOR AT LEAST SOME
HYBRID COLD AIR DAMMING FOR MONDAY NIGHT INTO TUESDAY. HOWEVER...
WPC STILL PREFERS TO KEEP POPS LOW WITH THE ARRIVAL OF THE FRONT
GIVEN THE APPARENT SPREAD IN GUIDANCE/ENSEMBLES GUIDANCE OVER THE PAST
FEW DAYS AND DIFFERENCES WITH THE OPERATIONAL MODELS VS THEIR
ENSEMBLES. THUS... FOR NOW PREFER TO KEEP POPS AT SLIGHT CHANCE FOR
MONDAY NIGHT INTO TUESDAY AND TREND TEMPS DOWNWARD. FOR WEDNESDAY...
WE MAY HAVE SOME FORM OF LINGERING CAD ACROSS THE AREA. HOWEVER...
THE PARENT SURFACE HIGH SHOULD BE WELL OFF THE NORTHEAST U.S. COAST
BY THIS TIME. THE NEXT SYSTEM WILL QUICKLY APPROACH FROM THE
NORTHWEST. HOWEVER... THERE IS A LARGE SPREAD AMONG THE GUIDANCE IN
TIMING OF THE FRONT. WPC HOLDS THE FRONT TO OUR NORTH DURING THIS
TIME FRAME... GOING WITH A LESS AMPLIFIED PATTERN. GIVEN THE LOWER
CONFIDENCE WILL KEEP TEMPS WITHIN A COUPLE CATEGORIES OF NORMAL AT
WORST... GIVEN THE LARGE POSSIBLE SPREAD IN TEMPS. THIS YIELDS HIGHS
ON TUESDAY IN THE UPPER 40S TO 50S... WITH HIGHS ON WEDNESDAY IN THE
50S TO SOME 60S... AND LOWS IN THE 30S AND 40S.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 1250 PM THURSDAY...
PRIMARY AVIATION CONCERNS THIS CYCLE: LOW CLOUDS AT NORTHERN
TERMINALS THROUGH 22Z. A COUPLE OF UPPER LEVEL DISTURBANCES CROSSING
NRN NC TODAY HAVE LED TO CONSIDERABLE SUB-VFR CLOUDS OVER THE
NORTHERN TERMINALS (INT/GSO/RDU/RWI) SO FAR TODAY. CIGS HAVE
IMPROVED A BIT TO MVFR AS THE SHOWERS HAVE BECOME A LITTLE MORE
PATCHY... AND EVEN IN SHOWERS... VSBYS HAVE HELD MOSTLY VFR. AS THE
DISTURBANCE SHIFTS EASTWARD LATE THIS AFTERNOON... CIGS WILL
STEADILY IMPROVE TO VFR... FIRST AT INT (WHERE THE MVFR CLOUDS HAVE
ALREADY BEGUN TO BREAK UP TO SCATTERED) AND GSO BY 21Z... AND ACROSS
TO RDU/RWI BY 00Z-01Z. SURFACE WINDS FROM THE NORTHWEST SUSTAINED AT
8-12 KTS HAVE HAD INFREQUENT GUSTS TO 15-20 KTS... AND THESE SHOULD
DIMINISH BY EVENING AS THE DISTURBANCE EXITS. CLEARING THIS EVENING
WILL YIELD UNLIMITED CIGS AND VSBYS AT ALL SITES AFTER 03Z. HIGH
CONFIDENCE IN VFR CONDITIONS WITH MOSTLY CLEAR SKIES AND LIGHT WINDS
THROUGH FRI... AS HIGH PRESSURE BUILDS IN FROM THE WEST.
LOOKING BEYOND 18Z FRI... VFR CONDITIONS ARE EXPECTED TO DOMINATE
THROUGH MON... ALTHOUGH AREAS OF MVFR OR IFR FOG ARE POSSIBLE EARLY
SUN MORNING AND EARLY MON MORNING. HIGH PRESSURE WILL SHIFT EASTWARD
OVER THE REGION THROUGH SAT... THEN MOVE EAST AND OFFSHORE SAT
NIGHT/SUN. A COLD FRONT WILL MOVE IN FROM THE NORTH LATE MON OR MON
NIGHT... BRINGING A GOOD CHANCE OF MVFR/IFR CONDITIONS MON NIGHT/TUE
AND PATCHY LIGHT RAIN. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/WSS
SHORT TERM...WSS/BSD
LONG TERM...BSD
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1105 AM EST THU NOV 27 2014
.SYNOPSIS...AN UPPER LEVEL DISTURBANCE AND ASSOCIATED LOW PRESSURE
SYSTEM WILL TRACK EAST ACROSS THE REGION THROUGH EARLY THIS
AFTERNOON. HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE WEST
LATE TODAY THROUGH TONIGHT... THEN SETTLE OVER THE CAROLINAS ON
FRIDAY AND SATURDAY... BEFORE PUSHING EAST OFF THE COAST SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1105 AM THURSDAY...
HAPPY THANKSGIVING!
FORECAST REQUIRED LITTLE CHANGE THIS MORNING. THE LEADING SHORTWAVE
TROUGH EVIDENT ON WATER VAPOR IMAGERY IS NOW WOBBLING ACROSS NORTH
CENTRAL NC... GENERATING NUMEROUS SHOWERS ACROSS THE NRN CWA. FAST
ON ITS HEELS IS THE SECOND WEAKER WAVE GENERATING SNOW SHOWERS ON
THE WEST SLOPES OF THE SOUTHERN APPALACHIANS... HOWEVER MUCH OF THIS
APPEARS TO BE DRYING UP AS THE PRECIP HEADS JUST EAST OF THE
MOUNTAINS WHERE THE LOW LEVEL FLOW HAS A NOTABLE DOWNSLOPE
COMPONENT. NEVERTHELESS... BOTH ON THE TAIL END OF THE LEADING WAVE
AND WITH THE SECOND WAVE AS IT SHIFTS EAST ACROSS THE STATE... WILL
NEED TO MONITOR FOR A FEW POCKETS OF MIXED RAIN AND WET SNOW OVER
THE EXTREME NNW CWA. IN FACT... KRAX DUAL POL PRODUCTS INDICATE THE
MELTING LEVEL AT AROUND 2200 FT... A BIT LOWER THAN RAP FORECAST
SOUNDINGS SUGGEST... SO WE COULD DEFINITELY SEE SOME WET FLAKES
WHERE PRECIP RATES ARE HIGHER. TEMPS RANGE FROM THE UPPER 30S TO
LOWER 40S NORTH TO THE UPPER 40S/NEAR 50 SOUTH... AND THE NORTHERN
HALF IS UNLIKELY TO SEE MUCH MORE THAN A ONE TO PERHAPS TWO CATEGORY
CLIMB FOR THE REST OF THE DAY... AND EVEN THEN ONLY IF WE CAN GET
ENOUGH SUNSHINE. THESE CHANCES DON`T LOOK TOO GOOD GIVEN THE
PERSISTENT MOISTURE IN THE LOW LEVELS NOTED ON UPPER AIR ANALYSES.
WILL ADJUST NORTHERN HIGHS DOWN JUST A TAD... TO RANGE FROM MID 40S
NORTH (AND AGAIN THIS MAY BE OPTIMISTIC) UNDER MOSTLY CLOUDY SKIES
TO MID 50S SOUTH (WHICH COULD BE PESSIMISTIC GIVEN THE FAIR SKIES
THERE). -GIH
TONIGHT...SKIES WILL CLEAR OFF FAIRLY QUICKLY WEST-TO EAST LATE THIS
AFTERNOON EARLY EVENING AS DRIER AIR OVERSPREADS THE REGION. COLD
AIR ADVECTION WILL KEEP THE NEAR SURFACE ATMOSPHERE WELL MIXED UNTIL
JUST PRIOR TO DAYBREAK. THE CAA WILL SEND TEMPS INTO THE MID-UPPER
20S BY EARLY FRIDAY.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 305 AM THURSDAY...
FRIDAY...CHILLY HIGH PRESSURE WILL BUILD INTO AND SETTLES OVERHEAD.
LOW LEVEL THICKNESSES AVERAGE 45M BELOW NORMAL...SUGGESTIVE OF MAX
TEMPS 10-14 DEGREES BELOW NORMAL. THIS YIELDS MAX TEMPS IN THE LOW-
MID 40S. SKIES WILL REMAIN MOSTLY CLEAR ASIDE FROM A FEW PASSING
CIRRUS IN THE AFTERNOON. -WSS
FRIDAY NIGHT: SURFACE HIGH PRESSURE WILL SETTLE OVER THE REGION ON
FRIDAY NIGHT. MEANWHILE... MID LEVEL FLOW WILL REMAIN OUT OF THE WNW
WITH THE POTENTIAL FOR A FEW WEAK DISTURBANCES TO MOVE ACROSS THE
MID ATLANTIC REGION. HOWEVER... WE WILL REMAIN DRY WITH ONLY AN
INCREASE IN SOME HIGH CLOUDS ON SATURDAY MORNING. STILL THINK THE
CLOUDS WILL BE THIN ENOUGH NOT TO HAVE A SIGNIFICANT IMPACT ON LOW
TEMPS. GIVEN THIS... THINK WE SHOULD SEE TEMPS PLUMMET INTO THE 20S
ACROSS THE ENTIRE AREA... WITH LOWS IN THE MID TO UPPER 20S (MAYBE
EVEN A FEW LOWER 20S IN THE USUAL RURAL COLD SPOTS DEPENDING ON THE
CLOUD COVER). -BSD
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 310 AM THURSDAY...
HIGH PRESSURE WILL SHIFT TO THE SOUTH AND EAST OF CENTRAL NC THIS
WEEKEND ALLOWING FOR A WARMING TREND. HIGH TEMPS ARE EXPECTED TO BE
IN THE LOWER TO MID 50S FOR SATURDAY AND LOWER TO MID 60S FOR
SUNDAY. MID LEVEL RIDGING IS FORECAST TO BUILD NORTHWARD DURING THIS
TIME FRAME AND NUDGE INTO OUR AREA. HOWEVER... AS A NORTHERN STEAM
TROUGH IS FORECAST TO TRACK NEAR THE U.S./CANADIAN (EAST COAST THAT
IS) BORDER DURING THIS TIME FRAME A TRAILING COLD FRONT WILL DROP
SOUTHWARD AND INTO CENTRAL NC EARLY NEXT WEEK. MODEL GUIDANCE HAS
TRENDED TOWARDS THE SURFACE FRONT MOVING INTO THE AREA ON MONDAY
NIGHT INTO EARLY TUESDAY MORNING... PUSHED BY A 1035-1040 MB SURFACE
HIGH TO THE NORTH/NORTHWEST. THIS SHOULD ALLOW FOR ONE LAST WARM DAY
ON MONDAY... WITH HIGHS IN THE 60S TO LOWER 70S SOUTH.
GIVEN THE LAST SEVERAL DAYS MEDIUM RANGE MODELS HAVE TRENDED WETTER
WITH THE AFOREMENTIONED FRONT AND THE POTENTIAL FOR AT LEAST SOME
HYBRID COLD AIR DAMMING FOR MONDAY NIGHT INTO TUESDAY. HOWEVER...
WPC STILL PREFERS TO KEEP POPS LOW WITH THE ARRIVAL OF THE FRONT
GIVEN THE APPARENT SPREAD IN GUIDANCE/ENSEMBLES GUIDANCE OVER THE PAST
FEW DAYS AND DIFFERENCES WITH THE OPERATIONAL MODELS VS THEIR
ENSEMBLES. THUS... FOR NOW PREFER TO KEEP POPS AT SLIGHT CHANCE FOR
MONDAY NIGHT INTO TUESDAY AND TREND TEMPS DOWNWARD. FOR WEDNESDAY...
WE MAY HAVE SOME FORM OF LINGERING CAD ACROSS THE AREA. HOWEVER...
THE PARENT SURFACE HIGH SHOULD BE WELL OFF THE NORTHEAST U.S. COAST
BY THIS TIME. THE NEXT SYSTEM WILL QUICKLY APPROACH FROM THE
NORTHWEST. HOWEVER... THERE IS A LARGE SPREAD AMONG THE GUIDANCE IN
TIMING OF THE FRONT. WPC HOLDS THE FRONT TO OUR NORTH DURING THIS
TIME FRAME... GOING WITH A LESS AMPLIFIED PATTERN. GIVEN THE LOWER
CONFIDENCE WILL KEEP TEMPS WITHIN A COUPLE CATEGORIES OF NORMAL AT
WORST... GIVEN THE LARGE POSSIBLE SPREAD IN TEMPS. THIS YIELDS HIGHS
ON TUESDAY IN THE UPPER 40S TO 50S... WITH HIGHS ON WEDNESDAY IN THE
50S TO SOME 60S... AND LOWS IN THE 30S AND 40S.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 635 AM THURSDAY...
A STRONG UPPER LEVEL DISTURBANCE CROSSING CENTRAL NC EARLY THIS
MORNING WILL EXIT OUR REGION BY EARLY THIS AFTERNOON. THIS SYSTEM IS
TRIGGERING PATCHES OF LIGHT RAIN ACROSS THE NORTHERN PIEDMONT AND
NORTHERN COASTAL PLAIN ALONG WITH VARYING CEILINGS...RESULTING IN
POCKETS OF LIFR CONDITIONS. CEILINGS ARE EXPECTED TO LIFT AND
DISSIPATE FROM THE SW LATER THIS MORNING...LEADING TO IMPROVING
AVIATION CONDITIONS.
AFTER 14Z...WEST TO NW SFC WINDS WILL BE BLUSTERY WITH GUSTS 18-23
KTS LIKELY. THE GUSTS WILL BECOME LESS LIKELY AFTER 22Z...THOUGH A
STEADY NW WIND AROUND 10KTS EXPECTED WELL INTO TONIGHT.
HIGH PRESSURE WILL BUILD INTO CENTRAL NC TONIGHT AND SETTLE OVERHEAD
FRIDAY THROUGH SATURDAY...PROVIDING A PERIOD OF VFR CONDITIONS WITH
SFC WINDS LESS THAN 10KTS.
THE HIGH WILL SHIFT OFFSHORE SUNDAY. THE RESULTING SOUTH-SOUTHWEST
LOW LEVEL FLOW WILL ADVECT MOISTURE INTO OUR REGION BY LATE SUNDAY-
SUNDAY NIGHT LEADING TO THE POTENTIAL FOR AREAS OF MVFR FOG OR IFR
CEILINGS IN STRATUS BY EARLY MONDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/WSS
SHORT TERM...WSS/BSD
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
123 PM EST THU NOV 27 2014
.SYNOPSIS...
WEAK CLIPPER EXITS SOUTHERN APPALACHIANS THIS MORNING. NORTHWEST FLOW
AND LINGERING MOISTURE PRODUCE UPSLOPE SNOW THROUGH TONIGHT. HIGH
PRESSURE FRIDAY AND SATURDAY. ANOTHER SYSTEM SUNDAY NIGHT AND MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
JUST A FEW ECHOES LEFT ON THE RADAR AS THE OVERNIGHT SYSTEM
ROTATES TO THE EAST. LOW LEVEL FLOW TO TURN NORTHWESTERLY WITH A
FETCH OFF OF LAKE MICHIGAN...SO WILL KEEP CLOUDS GOING WITH
INCREASING MOUNTAIN POPS INTO THIS EVENING.
PREVIOUS DISCUSSION...
A WEAK CLIPPER SYSTEM EXITS EASTERN KY AND EASTERN TN THIS
MORNING. ON ITS WAY...LIGHT SNOW SHOWERS WILL BE POSSIBLE ACROSS
SOUTHWEST VA...AND EXTREME SOUTHERN WV DURING THE MORNING HOURS.
HOWEVER...WIND BECOMES NORTHWEST...AND WITH LINGERING
MOISTURE...UPSLOPE SNOW SHOWERS ARE LIKELY OVER THE CENTRAL AND
NORTHEAST MOUNTAINS THROUGH TONIGHT. KEPT CHANCE POPS OVER THE
WESTERN SLOPES AND EASTERN MOUNTAINS AND LIKELY POPS OVER
ELEVATIONS HIGHER THAN 3000 FEET.
MODELS INDICATE THAT BY 00Z FRIDAY...OUR AREA STILL UNDER THE BACK
EDGE OF THE H500 TROUGH...ACCOMPANY BY A STRONG ELONGATED
VORTICITY MAXIMA. H850 CHARTS SHOW EVEN COLDER AIR ADVECTING FROM THE
NORTHWEST BRINGING H850 TEMPERATURES AROUND MINUS 11C. THESE
CONDITIONS WILL COMBINE WITH THE UPSLOPE COMPONENT TO PRODUCE AN
INCH OR TWO AT HIGHER ELEVATIONS OF LIGHT SNOW LATE THURSDAY.
USED THE HRRR NUMBERS FOR HIGH TEMPERATURES TODAY...AND WENT CLOSER
TO THE COLDEST ECMWF MOS NUMBERS FOR LOWS TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
WEAK SYSTEM PASSES BY TO THE NORTH ON SATURDAY. THEN A WEAK
BAROCLINIC ZONE DEVELOPS AND LINGERS OVER THE AREA FROM SATURDAY
THROUGH MONDAY WITH LOW POPS. FINALLY A MORE ORGANIZED SYSTEM
ROLLS THROUGH ON MONDAY...BUT MODELS VARYING WIDELY ON TIMING OF
THIS IMPULSE SO GENERALLY KEPT 30 TO 40 POPS OVER A LARGE PERIOD.
FRONT EXITS REGION ANYTIME BETWEEN MONDAY NIGHT TO TUESDAY
EVENING. NUDGED MORE TOWARDS SLOWER 00Z EURO. TOO WARM FOR SNOW
MOST PLACES DURING THE PERIOD.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
USED A BLEND OF THE ECMWF ENSEMBLE MEAN AND THE CURRENT FORECAST.
NEXT FRONTAL BOUNDARY PUSHES INTO THE REGION SUNDAY NIGHT INTO
MONDAY. MODELS THEN SHOW A WAVE MOVING ALONG THE FRONT FOR
TUESDAY...BUT QUESTIONABLE HOW MUCH OF THAT EFFECTS THE CENTRAL
APPALACHIANS. ECMWF AND GFS THEN DIVERGE CONSIDERABLY FOR WEDNESDAY
AND THURSDAY. USING THE ECMWF ENSEMBLE MEAN BRINGS A FRONT THROUGH
ON WEDNESDAY WITH SOME UPSLOPE SNOW POSSIBLE BEHIND THE FRONT
WEDNESDAY NIGHT INTO THURSDAY.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
NORTHWEST FLOW WILL RESULT IN UPSLOPE SNOW FOR THE EASTERN
TERMINALS FOR THE BULK OF THE TAF PERIOD. MVFR CEILINGS WILL BE A
GOOD BET FOR PREVAILING GOING FORWARD AND WILL TAKE VISIBILITIES
DOWN TO IFR AS THE CHANCES INCREASE FOR SNOW SHOWERS. CKB/EKN/BKW
ARE THE BEST BETS FOR PREVAILING SNOW CONDITIONS AFTER 21Z TODAY.
CANNOT RULE BRIEF SNOW CONDITIONS AT CRW AND PKB.
MET AND MAV GUIDANCE LOOKED TO BE TOO OPTIMISTIC IN TERMS OF
VISIBILITIES AT CKB AND BKW.
IN GENERAL...CEILINGS TO LIFT TO VFR AFTER 12Z...PERHAPS A COUPLE
HOURS LATER FOR THE MOUNTAINS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: VSBY OVER MOUNTAIN COUNTIES...INCLUDING
BKW...MAY BE MORE VARIABLE THAN INDICATED.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EST 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00
CRW CONSISTENCY H H H H H H H H M M M M
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H M M M M L L L L
PKB CONSISTENCY M H H H H H H H H M H H
CKB CONSISTENCY H H H H H H H H H H H M
AFTER 18Z FRIDAY...
IFR CONDITIONS IN SNOW SHOWERS MAY LINGER INTO EARLY FRIDAY OVER
WV MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JW
NEAR TERM...ARJ/26
SHORT TERM...JW
LONG TERM...RPY
AVIATION...26
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
102 PM EST THU NOV 27 2014
.SYNOPSIS...
WEAK CLIPPER EXITS SOUTHERN APPALACHIANS THIS MORNING. NORTHWEST FLOW
AND LINGERING MOISTURE PRODUCE UPSLOPE SNOW THROUGH TONIGHT. HIGH
PRESSURE FRIDAY AND SATURDAY. ANOTHER SYSTEM SUNDAY NIGHT AND MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
JUST A FEW ECHOES LEFT ON THE RADAR AS THE OVERNIGHT SYSTEM
ROTATES TO THE EAST. LOW LEVEL FLOW TO TURN NORTHWESTERLY WITH A
FETCH OFF OF LAKE MICHIGAN...SO WILL KEEP CLOUDS GOING WITH
INCREASING MOUNTAIN POPS INTO THIS EVENING.
PREVIOUS DISCUSSION...
A WEAK CLIPPER SYSTEM EXITS EASTERN KY AND EASTERN TN THIS
MORNING. ON ITS WAY...LIGHT SNOW SHOWERS WILL BE POSSIBLE ACROSS
SOUTHWEST VA...AND EXTREME SOUTHERN WV DURING THE MORNING HOURS.
HOWEVER...WIND BECOMES NORTHWEST...AND WITH LINGERING
MOISTURE...UPSLOPE SNOW SHOWERS ARE LIKELY OVER THE CENTRAL AND
NORTHEAST MOUNTAINS THROUGH TONIGHT. KEPT CHANCE POPS OVER THE
WESTERN SLOPES AND EASTERN MOUNTAINS AND LIKELY POPS OVER
ELEVATIONS HIGHER THAN 3000 FEET.
MODELS INDICATE THAT BY 00Z FRIDAY...OUR AREA STILL UNDER THE BACK
EDGE OF THE H500 TROUGH...ACCOMPANY BY A STRONG ELONGATED
VORTICITY MAXIMA. H850 CHARTS SHOW EVEN COLDER AIR ADVECTING FROM THE
NORTHWEST BRINGING H850 TEMPERATURES AROUND MINUS 11C. THESE
CONDITIONS WILL COMBINE WITH THE UPSLOPE COMPONENT TO PRODUCE AN
INCH OR TWO AT HIGHER ELEVATIONS OF LIGHT SNOW LATE THURSDAY.
USED THE HRRR NUMBERS FOR HIGH TEMPERATURES TODAY...AND WENT
CLOSER TO THE COLDEST ADJECE NUMBERS FOR LOWS TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
WEAK SYSTEM PASSES BY TO THE NORTH ON SATURDAY. THEN A WEAK
BAROCLINIC ZONE DEVELOPS AND LINGERS OVER THE AREA FROM SATURDAY
THROUGH MONDAY WITH LOW POPS. FINALLY A MORE ORGANIZED SYSTEM
ROLLS THROUGH ON MONDAY...BUT MODELS VARYING WIDELY ON TIMING OF
THIS IMPULSE SO GENERALLY KEPT 30 TO 40 POPS OVER A LARGE PERIOD.
FRONT EXITS REGION ANYTIME BETWEEN MONDAY NIGHT TO TUESDAY
EVENING. NUDGED MORE TOWARDS SLOWER 00Z EURO. TOO WARM FOR SNOW
MOST PLACES DURING THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
GENERALLY USED THE ECMWF ENSEMBLE MEAN FOR THE FORECAST...WITH A BIT
OF THE GFS BLENDED IN. HIGH PRESSURE SLIDES EASTWARD SATURDAY NIGHT
AND SUNDAY...PROVIDING A SOUTHERLY FLOW. NEXT FRONTAL BOUNDARY
PUSHES INTO THE REGION SUNDAY NIGHT INTO MONDAY. HANDLING OF THIS
FRONT BEYOND MONDAY BECOMES A BIT MURKY. SOME MODELS DEVELOP A WAVE
ALONG THE FRONT FOR TUESDAY WHILE OTHERS PUSH THE FRONT TO THE SOUTH
AND DISSOLVE IT. WILL KEEP SOME SMALL POPS TUESDAY INTO WEDNESDAY
DUE TO THE UNCERTAINTY...BUT CONFIDENCE IS LOW.
&&
.AVIATION /17Z THURSDAY THROUGH MONDAY/...
NORTHWEST FLOW WILL RESULT IN UPSLOPE SNOW FOR THE EASTERN
TERMINALS FOR THE BULK OF THE TAF PERIOD. MVFR CEILINGS WILL BE A
GOOD BET FOR PREVAILING GOING FORWARD AND WILL TAKE VISIBILITIES
DOWN TO IFR AS THE CHANCES INCREASE FOR SNOW SHOWERS. CKB/EKN/BKW
ARE THE BEST BETS FOR PREVAILING SNOW CONDITIONS AFTER 21Z TODAY.
CANNOT RULE BRIEF SNOW CONDITIONS AT CRW AND PKB.
MET AND MAV GUIDANCE LOOKED TO BE TOO OPTIMISTIC IN TERMS OF
VISIBILITIES AT CKB AND BKW.
IN GENERAL...CEILINGS TO LIFT TO VFR AFTER 12Z...PERHAPS A COUPLE
HOURS LATER FOR THE MOUNTAINS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: VSBY OVER MOUNTAIN COUNTIES...INCLUDING
BKW...MAY BE MORE VARIABLE THAN INDICATED.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EST 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00
CRW CONSISTENCY H H H H H H H H M M M M
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H M M M M L L L L
PKB CONSISTENCY M H H H H H H H H M H H
CKB CONSISTENCY H H H H H H H H H H H M
AFTER 18Z FRIDAY...
IFR CONDITIONS IN SNOW SHOWERS MAY LINGER INTO EARLY FRIDAY OVER
WV MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/JW
NEAR TERM...ARJ/26
SHORT TERM...JW
LONG TERM...RPY
AVIATION...26
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1045 AM CST THU NOV 27 2014
.UPDATE...
SKIES CONTINUE TO SLOWLY CLEAR IN THE WESTERN FORECAST AREA THIS
MORNING. RAP AND NAM SOUNDINGS ARE REALLY SLOW TO CLEAR SKIES
ACROSS THE REMAINDER OF THE AREA TODAY...BUT PUTTING MORE STOCK IN
THE SATELLITE IMAGES RIGHT NOW WHICH WOULD INDICATE EARLIER
CLEARING. TEMPS ARE NOT EXPECTED TO GET MUCH HIGHER THAN WHERE
THEY ARE AT THIS POINT DUE TO COLDER TEMPS ALOFT ADVECTING IN
BEHIND THE DEPARTING SHORTWAVE.
&&
.AVIATION/18Z TAFS/...
SKIES WILL CONTINUE TO CLEAR WEST TO EAST DURING THE AFTERNOON AS
HIGH PRESSURE MOVES INTO THE REGION. MID TO HIGH LEVEL CLOUDS WILL
THEN MOVE WEST TO EAST OVER TAF SITES LATE IN THE EVENING. MVFR CIGS
LIKELY FRIDAY MORNING INTO THE AFTERNOON. UP TO A COUPLE TENTHS OF
AN INCH OF SNOW IS POSSIBLE FRIDAY MORNING WITH THE GREATEST CHANCE
FOR SNOW NORTH OF TAF SITES.
&&
.PREV DISCUSSION... /ISSUED 346 AM CST THU NOV 27 2014/
SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE...HIGH
THE 250 MB UPPER TROUGH AXIS OVER THE GREAT LAKES WILL MOVE TO THE
NORTHEAST U.S. TONIGHT AS THE UPPER LEVEL FLOW BECOMES MORE ZONAL.
THE NOSE OF AN UPSTREAM 130 KNOT JET MAX ACROSS THE NORTHERN PLAINS
PUSHES INTO WESTERN WISCONSIN BY SUNRISE FRIDAY. THIS INCREASES THE
UPPER DIVERGENCE TONIGHT...BUT IT IS WEAK.
A MID LEVEL TROUGH EXITS SOUTHEAST WISCONSIN THIS MORNING RESULTING
IN MID LEVEL DRYING. NAM FORECAST SOUNDINGS STILL SHOW LINGERING LOW
LEVEL MOISTURE BELOW 5 THSD FT. THE DRYING CONTINUES THIS
AFTERNOON...BUT A SHALLOW...MOIST LAYER REMAINS.
MAIN FORECAST PROBLEM WILL BE HOW QUICK TO BRING IN CLEARING FROM
THE WEST AS THE SURFACE HIGH PRESSURE RIDGE REACHES THE UPPER
MISSISSIPPI VALLEY. ALSO SOME FLURRY POTENTIAL TIL MID MORNING. THE
GFS MOS CLEARS THE SKIES...WHILE THE NAM MOS KEEPS IT CLOUDY. WILL
GO WITH A SLOWER CLEARING THAN THE GFS BUT NOT AS PESSIMISTIC AS THE
NAM...WHICH OFTEN OVER DOES THE SHALLOW MOIST LAYER.
HIGHS WILL BE WELL BELOW NORMAL FOR THANKSGIVING.
WARM AIR ADVECTION OCCURS LATER TONIGHT IN THE LOW TO MID LEVELS.
THE MID LEVELS WILL BE DRY INITIALLY. ISENTROPIC LIFT AND A GRADUAL
SATURATION WILL OCCUR LATE TONIGHT. SOME LIGHT SNOW MAY REACH THE
GROUND MAINLY NORTHWEST OF MADISON TOWARDS SUNRISE FRIDAY MORNING.
FRIDAY...FORECAST CONFIDENCE MEDIUM.
THE BEST CHANCE FOR SNOW WILL BE FRIDAY MORNING. THIS IS WHEN THERE
WILL BE MAX THETA-E ADVECTION AND ISENTROPIC LIFT OVER SOUTHERN WI.
THE LOW TO MID LEVEL WARM AIR ADVECTION WILL BE PERSISTENT ALL DAY
LONG. BY THE AFTERNOON... THE MID LEVELS WILL BECOME WESTERLY AND
DRY OUT WHILE THE LOW LEVELS REMAIN MOIST AND SOUTHERLY.
IT MAY TAKE A LITTLE WHILE TO SATURATE FROM THE TOP DOWN FRIDAY
MORNING... ESPECIALLY TOWARD SHEBOYGAN. EVENTUALLY... EXPECTING
LIGHT SNOW IN THAT AREA BY LATE FRIDAY MORNING. THEN THE BEST
FORCING AND DEEPER MOISTURE SHIFTS NORTH FOR THE AFTERNOON... SO I
TAPERED OFF THE POPS FROM SOUTH TO NORTH THROUGH THE DAY. BY EARLY
EVENING... THERE MAY STILL BE JUST ENOUGH ISENTROPIC LIFT AND LOW
LEVEL MOISTURE TO SUPPORT FREEZING DRIZZLE TOWARD SHEBOYGAN AS WE
LOSE THE ICE CRYSTAL GROWTH DUE TO DRY AIR ALOFT. OVERALL... I
BACKED OFF ON THE FREEZING DRIZZLE POTENTIAL FOR MOST OF THE
FORECAST AREA. IT SHOULD BE TOO DRY.
SNOW AMOUNTS WILL BE LIGHT WITH UP TO TWO TENTHS OF AN INCH ALONG
AND NORTH OF I-94 AND AROUND AN INCH OR MAYBE TWO TOWARD SHEBOYGAN.
DESPITE THE WARM AIR ADVECTION... MODELS ARE HINTING AT SLIGHTLY
COOLER HIGHS ON FRIDAY THAN WHAT WE HAD IN THERE BEFORE. IT NOW
LOOKS LIKE UPPER 20S TO AROUND 30 FOR A HIGH. THIS IS DUE TO OUR
COLD START AND THE SNOW COVER AND EXPECTED LOW CLOUDS.
LONG TERM...
FRIDAY NIGHT THROUGH SATURDAY... FORECAST CONFIDENCE MEDIUM.
SURFACE LOW PRESSURE CROSSING THE NORTHERN PLAINS WILL HELP TO DRAW
WARMER TEMPERATURES INTO SOUTHERN WI ON SATURDAY. TEMPERATURES WILL
DROP A LITTLE IN THE EVENING BUT THEN RISE AND HOLD STEADY AROUND 30
AFTER MIDNIGHT. TEMPERATURES WILL RISE THROUGH THE DAY SATURDAY...
REACHING THE LOWER 40S IN MOST AREAS. SOUTHEAST WI COULD SEE MID
40S. THE SNOW COVER AND PROBABLE FOG AND LOW CLOUDS FROM MELTING
SNOW COULD LIMIT OUR TEMPERATURES SO I KEPT THEM ON THE CONSERVATIVE
SIDE.
THERE WILL NOT BE A LOT OF MOISTURE WITH THIS WARMTH... SO WE WILL
FINALLY GET INTO A PERIOD OF QUIET WEATHER WITH MILD TEMPERATURES.
MODELS ARE STILL TRYING TO PAINT LIGHT QPF ACROSS SOUTHERN WI... BUT
THEY MAY BE PICKING UP ON MELTING SNOW AND FOG POTENTIAL OR POSSIBLY
SOME LIGHT DRIZZLE. THERE IS TOO MUCH UNCERTAINTY FOR THAT SO I KEPT
IT OUT OF THE FORECAST.
SATURDAY NIGHT THROUGH SUNDAY NIGHT... FORECAST CONFIDENCE HIGH.
A COLD FRONT WILL DROP DOWN THROUGH WI SATURDAY NIGHT INTO SUNDAY
MORNING. TEMPS WILL REMAIN STEADY IN SOUTHEAST WI THROUGH THE NIGHT
AND SUNDAY... THEN DROP QUICKLY SUNDAY EVENING IN THE WAKE OF THIS
FRONT. WINDS WILL BE A LITTLE BRISK OUT OF THE NORTHWEST SUNDAY
AFTERNOON WITH THE STEEP LOW LEVEL LAPSE RATES DUE TO COLD AIR
ADVECTION. THE WEATHER LOOKS DRY WITH THIS FRONTAL PASSAGE ON SUNDAY.
MONDAY THROUGH TUESDAY... FORECAST CONFIDENCE MEDIUM.
THE COLD AIR WILL HANG AROUND THROUGH MONDAY NIGHT WITH DRY HIGH
PRESSURE OVERHEAD. LOW PRESSURE CROSSING ONTARIO OR LAKE SUPERIOR
WILL ALLOW FOR WARMER TEMPERATURES IN SOUTHERN WI ON TUESDAY. AN
ASSOCIATED COLD FRONT MAY BRING LIGHT SNOW TO PORTIONS OF EAST
CENTRAL WI TUESDAY NIGHT.
WEDNESDAY THROUGH THURSDAY... FORECAST CONFIDENCE LOW.
THE GFS TRIES TO BRING A SYSTEM INTO THE MIDWEST THAT WOULD HAVE
MIXED PRECIP OVER SOUTHERN WI WEDNESDAY NIGHT THROUGH THURSDAY. THE
ECWMF MAINTAINS A DRY FORECAST WITH HIGH PRESSURE OVER THE AREAS.
USED CONSENSUS POPS AND TEMPS FOR NOW WITH LOW CONFIDENCE.
AVIATION/12Z TAFS/...
THE SNOW WILL BE MOVING OUT BUT THERE COULD STILL BE SOME LINGERING
FLURRIES THROUGH MID MORNING. EXPECT A PERIOD OF MVFR CLOUDS THIS
MORNING BEFORE A GRADUAL DECREASE IN CLOUDS FROM THE WEST DURING THE
AFTERNOON AS A RIDGE OF HIGH PRESSURE MOVES INTO WISCONSIN EARLY
THIS EVENING.
CLEARING WILL BE SHORT LIVED AS MOISTURE INCREASES IN THE MID AND
UPPER LEVELS LATE TONIGHT. SOME MVFR LIGHT SNOW MAY REACH THE
GROUND MAINLY NORTHWEST OF MADISON TOWARDS SUNRISE FRIDAY MORNING.
MARINE...
NORTHWEST WINDS WILL BE BREEZY THURSDAY. THERE MAY BE A FEW GUSTS TO
25 KNOTS...AND WAVES TO 4 FEET TOWARD OPEN WATERS. OVERALL
THOUGH...CONDITIONS SEEM TOO BORDERLINE FOR A SMALL CRAFT ADVISORY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV/SM
TODAY/TONIGHT AND AVIATION/MARINE...HENTZ
FRIDAY THROUGH WEDNESDAY...MRC