Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/17/16
Area Forecast Discussion
National Weather Service Wakefield VA
946 PM EST Wed Nov 16 2016
.SYNOPSIS...
A weak trough of low pressure pushes through the Mid Atlantic and
Northeast states through this evening...with high pressure then
building over the local area Thursday and Friday. A strong cold
front pushes across the region Saturday night, with cooler and
continued dry weather expected for late in the weekend into early
next week.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
No major changes nec to the previous forecast. Chance of rain has
ended over the Lwr Eastern Shore so have removed pops there.
Overnight low temps in the upr 30s to lwr 40s most areas, with
mid/upr 40s near the coast.
Previous discussion...
Latest analysis indicating ~1020mb surface high pressure extending
from the West-Central Gulf Coast into the Mid-South and Southern
Appalachians. To the north, ~1010MB SFC with low pressure
continues to slide across northern New England, with the
associated weak sfc cool front extending back into the eastern
Ohio Valley. Aloft, quick moving shortwave trough digging across
the interior northeast toward the Delmarva, as strong, broad upper
ridging builds across the Mississippi River Valley.
Noting a narrow area of isolated to widely scattered showers
focused along and ahead of the front/sfc trough over central PA
into western MD. Height falls are minimal ahead of the sheared
vorticity lobe and modeled omega fields also indicate limited
available forcing for ascent. Precipitable water values per the
RAP and NAM remain no higher than 0.5-0.75", and expect that
minimal lift will likely not be sufficient to overcome the limited
moisture and dry sub- cloud layer to produce widespread rainfall.
However, given obs upstream, showing a smattering of trace/light
pcpn amounts over SW/South Central PA from this morning into early
aftn, have added iso-sct shower wording for late aftn/early
evening for the Lower Maryland Eastern Shore. QPF would be no
more than a few hundredths at the most over locations that can
pick up a quick shower through early evening.
Otherwise, warm W-SW flow has allowed for temperatures to warm
well into the 50s to lower 60s across the area under a mainly
clear sky. Do expect an increase in mid level clouds over the next
few hours, especially across the northeast where sky will likely
briefly become mostly cloudy to overcast this aftn/early evening.
Tonight...
Shortwave pushes offshore by midnight, as the shearing front
crosses the area. Any lingering clouds should erode quickly from
west to east as drier air pushes east. look for early morning
lows to average in the upper 30`s to low 40`s inland to mid to
upper 40`s near the coast.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
Broad ridging at the sfc and aloft builds over the eastern third
of the nation, in response to another strong trough digging into
the Desert Southwest. Large scale subsidence behind departing
upper trough will bring mainly clear/sunny conditions through the
period. Warm, dry conditions will eventually give way to sharply
colder air for the latter half of the weekend as previously
referenced west coast trough translates east Friday/Saturday, with
the attendant strong cold front crossing into the area late
Saturday.
Thursday...
Minimal cold air advection behind the front tonight
and into Thursday. In fact, 850Mb temperatures actually warm to
+10 to +12C by Thu aftn. Model cross-sections continue to indicate
a reasonably sharp low-level inversion developing which will
prevent maximum mixing, keeping temps well below the potential
numbers that local thickness tools are indicating, especially with
breezy N-NW flow along the coastal plain. That said, expect
temperatures to gradually warm through the period. Look for high
temperatures warming into the mid to upper 60`s over the piedmont
Thursday under a sunny sky. Meanwhile, NNW flow will keep
temperatures Thursday similar to those of today over the eastern
half of the area...mainly in the low to mid 60s. Decoupling winds,
clear sky and high pressure overhead will bring a seasonably cold
night Thursday night with lows ranging from the mid 30s to lower
40s.
Friday...
The upper ridge axis locates over the Mid- Atlantic region on
Friday, as surface high pressure becomes centered along the
Southeast coast. Warming trend commences as return SSW flow
develops. GEFS plumes indicate 850mb temps warm to +12 to +14C, as
pronounced low-level inversion mixes out a bit more. This should
allow for a markedly warmer day on Friday, with maxima warming
into the low to mid 70s inland (+1 standard deviation) with mid
to upper 60`s near the coast. A bit milder Friday night with lows
mainly in the 40s to near 50 along the coast.
Saturday...
Remaining warm on Saturday, with the front not crossing through
until late in the day out west into early Sat night along the
coast. Once again, minimal forcing and dry PW/Dry sub-cloud layer
makes pcpn quite unlikely aside from perhaps some scant/trace
amounts with the actual frontal passage. For that reason, have
capped pop Saturday afternoon at no higher than 20%. Highs
Saturday in the upper 60s to low 70s.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A potent upper level trough (-2 st dev) will sweep across the
eastern seaboard Saturday night into Sunday. A strong cold front
will accompany this trough with 850mb temperatures dropping to
around -5 to -8C by Sunday. The airmass will remain rather well
mixed Saturday night and hence low temperatures should only drop
into the mid 30s inland to around 40 at the coast, and then highs
only rising into the mid 40s to around 50 Sunday, which are around
-1 to -1.5 st dev below seasonal means. Windy conditions are
expected Sunday with a nw wind of 15-25 mph expected, with gusts
of 30-35 mph possible, and locally stronger over the Eastern Shore
with a nw wind of 20-30 mph and gusts up to 40 mph possible.
Moisture will be limited with this system with only a 20-40% PoP
for showers Saturday evening from e- central VA to the coast.
Surface high pressure then gradually builds into the area Sunday
night into Monday. Forecast lows Sunday night range from the mid
20s to low 30s, with highs Monday in the upper 40s to low 50s.
High pressure remains in vicinity of the coast Monday night and
then gradually slides offshore Tuesday. Forecast lows Monday night
range from the upper 20s to low 30s, with highs Tuesday moderating
into the low/mid 50s. High pressure slides farther offshore by the
middle of next week as another trough and associated cold front
push through the Great Lakes and Ohio Valley.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
A weak surface boundary will cross the region tonight. High pressure
builds back into the area for Thursday and Friday. A strong cold
front moves through the Mid Atlantic States Saturday night. Dry
conditions can be expected behind the front late this weekend and
into early next week.
Mainly clear skies (VFR conditions) are expected tonight. Shower
activity and clouds near SBY will continue to diminish as the
boundary continues to move west. Winds should remain just high
enough tonight to limit the fog potential. Winds will gradually
shift to the N/NW later tonight as the surface boundary crosses the
region. VFR and dry conditions are expected for Thursday.
Outlook: VFR and dry conditions are expected to continue through
midday Saturday. There will be a chance for showers early Sunday
(highest chance across the NE at SBY). Continued dry weather early
next week but with periodic MVFR ceilings possible at SBY Sun/Mon.
&&
.MARINE...
A weak trough of low pressure will clip the coast tonight.
This will result in a nnw wind of 15-20kt over the ocean and 10-15kt
elsewhere late tonight through Thursday morning. High pressure will
then prevail over the marine area Thursday aftn through Friday. A nw
wind aob 15kt Thursday aftn into Thursday night will become light
and back to the sw Friday. High pressure then slides offshore Friday
night into early Saturday as a strong cold front approaches from the
nw. A sw wind of 5-10kt is expected Friday night and then increases
to 10-15kt early Saturday. The cold front is expected to sweep
across the area late Saturday aftn into Saturday evening. A WNW wind
should sharply increase in the wake of the front with strong caa
and gale force gusts are possible Saturday night into Sunday. A nw
wind of 15-25kt should continue Sunday night into Monday as high
pressure builds across the Southeast and low pressure departs well
to the ne of the region. Seas/waves should generally be
2-3ft/1-2ft through early Saturday, and then increase to
5-6ft/3-5ft in the wake of the cold front, before gradually
subsiding to 4-5ft/2-4ft Sunday night into Monday.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...None.
&&
$$
SYNOPSIS...MAM
NEAR TERM...MAS/MAM
SHORT TERM...LKB/MAM
LONG TERM...AJZ
AVIATION...AJB/MAM
MARINE...AJZ
Area Forecast Discussion
National Weather Service Bismarck ND
939 PM CST Wed Nov 16 2016
.UPDATE...
Issued at 926 PM CST Wed Nov 16 2016
Latest NAM has come in a little farther south and east with the
track of the surface low and resulting area of heaviest snow. No
significant changes at this time but certainly something to
monitor as models continue to come in this evening.
For the late evening update we increased clouds tonight as
stratus shield dropping south has moved in faster than previously
forecast. Some light returns showing up on Bowman radar over the
far southwest. Think most precip not likely reaching the ground so
kept the chance of precipitation out of the forecast through
midnight. After midnight utilized a blend of current pops with a
time lagged HRRR solution, which basically slowed the northward
and eastward progression of any accumulating precipitation through
12 UTC.
UPDATE Issued at 518 PM CST Wed Nov 16 2016
No significant changes to the going forecast. Low pressure was
located over southern Manitoba with northwest to north winds
across the forecast area. Strongest winds currently over the
northwest. Expect the winds to diminish here as boundary layer de-
couples. Winds over the southeast just behind the weak front will
pick up a bit this evening as pressure gradient increases. Mainly
mid and high level clouds across the forecast area early this
evening. An area of lower clouds will make its way from
Saskatchewan south across the forecast area tonight. Made some
minor tweaks to sky cover based on latest satellite analysis and
updated latest sensible weather elements. Updated text products
will be sent shortly.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 132 PM CST Wed Nov 16 2016
Current surface analysis place trough/frontal boundary over the
northern/central plains with ridge over the midwest. Upper level
analysis places ridging over the midwest with trough digging over
the northern Sierra into the Great Basin. Mainly quiet weather
remains over our area with some clouds pushing through as a weak
short wave lifts through the region.
Main concern for this forecast package continues to be the storm
system coming Thursday night & Friday which will graze our
southeastern areas.
For tonight...upper trough digs over the Great Basin and pushes
into the southern/central Rockies. Southwest flow deepens over our
area as initial wave sliding up the flow pushes into the
southwest, bringing low chances for precipitation. Cold air starts
to wrap into the area behind aforementioned frontal boundary.
On Thursday...upper low closes off over Colorado and ejects into
the central plains. Colder air continues to pour into the region
as surface low pushes towards Kansas. Precipitation chances
spread across southern areas starting out as a rain/snow mix
shifting more towards snow as the cold air pours in. Winds will be
on the increase...particularly over the south/east where pressure
gradient will be tighter.
.LONG TERM...(Thursday night through Wednesday)
Issued at 132 PM CST Wed Nov 16 2016
Low pressure system attempts to become stacked as it lifts towards
the Iowa/Minnesota border overnight Thursday. Current trajectory
of the storm keeps the brunt of snow to our south and east. With
that said, most models have come into rather good agreement with
keeping snow more or less southeast of a line from Harvey to
Bismarck to Bowman. The heavier snow in our area will remain over
the far southern James River Valley, where around 4 to 6 inches of
snow are expected at this point. Gusty winds continue overnight,
particularly over the southeast closer to the low in the tighter
pressure gradient, while cold air continues to pour in. Wind chill
values get rather chilly, with most locations dipping to around 10
above by early Friday morning.
On Friday...low continues to lift northeast and starts to open up
near western Lake Superior by late afternoon. Snow over the
southeast will gradually taper through the morning, with most
ending by mid-day. A chilly day remains on tap over most
locations with gusty northerly winds and high temperatures at or
slightly below freezing.
Going into the weekend into early next week...broad ridging
develops over the western CONUS with a very gradual warming trend
developing. With that said, temperature forecast will be rather
tricky over areas that receive snowfall. Dry conditions will
prevail.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 926 PM CST Wed Nov 16 2016
An area of MVFR Ceilings has dropped south through KISN and KMOT
this evening. This is expected to move south to the southern TAF
sites after midnight with occasional periods of IFR Ceilings a
possibility at KDIK Thursday morning. A strong low pressure
system to our south will bring increasing northwest winds and a
mix of rain and snow to KBIS and KJMS Thursday afternoon.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
Winter Storm Watch from Thursday evening through Friday
afternoon for NDZ048-050-051.
&&
$$
UPDATE...TWH
SHORT TERM...JJS
LONG TERM...JJS
AVIATION...TWH
Area Forecast Discussion...UPDATED
National Weather Service BROWNSVILLE TX
553 PM CST Wed Nov 16 2016
.DISCUSSION...Updated for latest aviation discussion below.
&&
.AVIATION...After times of dense fog at area airports the past two
nights, VFR should generally prevail over the next 24 hours...with
a couple possible caveats: Patchy fog still not out of the
question later tonight, but most statistical guidance is
downplaying this, except for a few hours of MVFR mist at MFE. RAP
forecast soundings support this idea, so will include in TAF but
keep visibility at 6SM for now. SREF also suggests some MVFR
ceilings possible for the mid-Valley late tonight into early
tomorrow morning (which would include MFE and HRL), but with
probabilities < 40% and little backing from other statistical
guidance, not too confident of this just yet.
Winds have shifted to SE and will become more SSE by late morning
tomorrow and increase in speed. Readings of 20G26KT at all three
terminals will be common.
&&
.PREV DISCUSSION... /issued 303 PM CST Wed Nov 16 2016/
SHORT TERM (Tonight through Thursday Night): 500mb ridge across
the east-central United States this afternoon will shift eastward
tomorrow as a 500mb trough moves eastward across the western
United States. Low to mid level moisture will return across
northeast Mexico into southwest Texas Thursday into Thurs night.
At the surface...surface high pressure across the western Gulf of
Mexico will move eastward tonight into Thursday allowing an
onshore flow to develop. Lows tonight will be warmer compared to
last night as the dewpoints recover across the CWA. Winds will
also increase tonight into Thursday and there will be enough
mixing to inhibit dense fog but some patchy fog is possible across
portions of the Rio Grande valley late tonight into early Thurs
morning. Isolated showers will develop across the coastal waters
Thurs night as moisture continues to increase across the lower TX
coast. Otherwise...not much in the way of rain chances are
expected across the inland areas through the period. Temperatures
will continue to above normal during the afternoon tomorrow with
the southerly flow across the area.
LONG TERM (Friday through Wednesday): A fairly progressive upper
level pattern is expected through the period. 500 mb ridge over
the southeastern US gets nudged eastward Friday as a trough and
vigorous upper level disturbance tracks across the plains, pushing
a cold front across Texas. By Saturday, 500 mb ridging builds in
quickly, with a midlevel trough approaching Texas on Tuesday,
another cold front pushing through Texas on Wednesday.
Another warm day is expected Friday, with temperatures topping out
in the mid 80s. Cloud cover will be on the increase as moisture
streams northward and pools ahead of the front. A few showers will
be possible Friday afternoon. The cold front is set to surge
across the northern ranchlands Friday evening and through
Brownsville by midnight. Have maintained mention of showers and
thunderstorms with the front, with the best chances of thunder
primarily across the coastal areas. Upper level support is not the
greatest, with the best forcing further north. Behind the front,
strong northeasterly winds will develop. Drier air will work in,
quickly cutting off rain chances and clearing skies out from the
northwest to the southeast during the day Saturday. CAA will
result in a significant change in temperatures this weekend, with
high temperatures only in the 60s on Saturday and temperatures
dropping into the 40s across much of the inland areas, with
temperatures a little warmer closer to the coast. Cooler
temperatures continue Sunday, before temperatures begin to rebound
on Monday and Tuesday, with highs once again back in the 80s, as
500 mb ridging prevails.
MARINE(Tonight through Thursday night): Seas were near 1 foot with
east southeast winds near 2 knots this afternoon. Light to moderate
southeast winds will prevail across the coastal waters tonight as
surface high pressure across the western Gulf of Mexico moves
eastward. The pressure gradient will increase across the lower Texas
coast Thursday with low pressure developing along the lee side of
the Rockies and high pressure across the southeast United States.
Winds will veer to the south to southeast Thursday and increase
during the afternoon. Moderate to strong south to southeast winds
will prevail across the western Gulf Thursday through Thurs night.
SCEC conditions likely offshore the lower TX coast Thursday into
Thurs night as a result.
Friday through Monday...Moderate southeasterly winds early Friday
will diminish through the morning and afternoon hours as a cold
front approaches the region. Cold front will move across the lower
Texas coastal waters late Friday evening with strong northeasterly
winds and building seas behind it. Occasional gusts to gale force
are possible Friday night and early Saturday across the Gulf
waters. Small craft advisories will be needed Friday night through
Saturday on the Laguna Madre for winds and through Saturday night
for higher winds and seas on the Gulf waters. Winds and seas
gradually subside late Saturday into Sunday as high pressure
pushes into the area and moderate southeasterly winds return on
Monday.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
This product is also available on the web at:
HTTP://WEATHER.GOV/RGV
53-Schroeder...Aviation/Short-term
60...Long-term
Area Forecast Discussion
National Weather Service Columbia SC
917 PM EST Wed Nov 16 2016
.SYNOPSIS...
Dry high pressure will extend into the area from the west through
Friday with above normal temps. A dry cold front will come
through Saturday, reinforcing dry conditions with cooler temps for
the weekend and into next week. Smoke from wildfires in the
southern Appalachians will continue to affect the region through
much of the period.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Update 630 pm: Winds have diminished at the surface and
temperatures have dropped off by 10 degrees or more in the past
hour as the overnight inversion sets up. The flow aloft remains
out of the northwest, therefore smoke will continue be an issue
for The Midlands and CSRA. The existing forecast has this well in
hand.
The forecast area will be situated between an upper trough axis
moving off the east coast and an upper ridge building from the
Gulf of Mexico into the eastern Great Lakes. This will promote
northwesterly flow aloft across the forecast area. Surface high
pressure over the central Gulf will gradually shift northeastward
into the region. The air mass will remain relatively dry with
precipitable water values around half an inch. Smoke from the
southern Appalachian wildfires will continue to be the main
forecast issue. Northwesterly low-level winds will allow the
smoke to filter into the forecast area. Overnight lows will be
mainly in the upper 30s to lower 40s with smoke.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
Surface/Upper level ridge over the Gulf coast will build
northeast over the Southeastern States as upper trough moves from
the Northern Plains toward the Mississippi valley. A dry air mass
will remain in place. Strong subsidence will result in above
normal mild afternoon temperatures and cool nights with dry air in
place and favorable net radiational cooling conditions. With
surface high centered over the area and light winds...smoke
should remain trapped in the area at least through Thursday. This
is supported by the latest HRRR smoke model guidance. Winds from
the southwest Friday may result in improving conditions with
regards to smoke...although winds remain light.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A strong cold front will move through the region Saturday
afternoon. Moisture will be limited with the front and showers
appear at most isolated mainly north of the region. Mild
temperatures ahead of the front but strong cold advection
developing in the afternoon with gusty west-northwest winds
possibly up to 30 mph. This may spread smoke back into the area
through mixing in the boundary layer should increase smoke
dispersion. Temperatures below normal through much of the period
with cold nights with favorable net radiational cooling
conditions. A freeze is possible Saturday night but more likely
Sunday night.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
A dry surface ridge will extend through the area through the TAF
period. The upper ridge axis will be west of the area. The
pattern supports clear skies and most of the NAM and GFS MOS and
SREF guidance indicate VFR conditions. However, smoke from the
Southern Appalachians fires will continue to be an issue. The
smoke combined with strong net radiational cooling should help
enhance the fog threat during the early morning hours. We
forecasted a period of MVFR or IFR fog during the early morning
hours with the greatest restrictions at the river valley terminals
of AGS and OGB. Heating and mixing should dissipate fog around 14z
but smoke may linger with light and variable winds. Expect this
fog would be in the high-end MVFR or vfr category because of
mixing during the late morning and afternoon.
EXTENDED AVIATION OUTLOOK...Reduced visibilities in smoke and fog
could continue through Friday. Lower VSBYS would be expected
during the early morning hours with some improvement in the
afternoon because of mixing.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
SYNOPSIS...99
NEAR TERM...99
SHORT TERM...99
LONG TERM...99
AVIATION...99
Area Forecast Discussion
National Weather Service Wilmington OH
912 PM EST Wed Nov 16 2016
.SYNOPSIS...
Surface high pressure will build across the region, offering
dry weather and warmer temperatures through Friday. Breezy
conditions, lower relative humidity values and fuel moisture
values dropping close to 8 percent will result in elevated fire
weather concerns Friday. A cold front will cross the area Friday
night, bringing rain showers with a few snow showers possible
in the much colder air Saturday.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Have made another update to add a dense fog advisory to the
northern tier of counties. While the rest of the discussion below
is still valid, and the fog may shift northward later in the
overnight period, it has expanded enough to impact several
counties within the ILN forecast area. KMRT and KDLZ are currently
reporting visibilities at or below 1/4SM, with a close look at the
11u-3.9u satellite suggesting these conditions are also affecting
other areas not covered by observing equipment.
Previous discussion (848 PM) >
The main focus for this update was to address fog potential,
particularly in the far northern sections of the ILN CWA. The
latest 11u-3.9u satellite imagery indicates a growing expanse of
dense fog in northwest Ohio, affecting areas from the end of the
Marblehead peninsula to Van Wert, and extending as far north as
Toledo. The southern expanse of this fog has been slow to grow,
but is starting to nudge toward northern Hardin County. Some
additional dense fog is beginning to develop in Union and Delaware
counties. Radiational cooling conditions are near-ideal through
the first half of the overnight period, which should allow for
some expansion of the fog in the near term. However, dry
southeasterly flow is eventually expected to increase, with the
pressure gradient beginning to tighten across the middle
Mississippi Valley and western Ohio Valley. HRRR visibility
projections suggest that the main shield of dense fog will remain
north of the ILN CWA, eventually retrograding further north after
08Z. However, some potential for patchy dense fog will exist,
forcing the inclusion of fog in the weather grids. Temperatures
are also trending cooler than anticipated -- much cooler in the
far east. Using HRRR/RAP forecasts as guidance, min temps were
lowered by several degrees.
Previous discussion (445 PM) >
Amplified mid/upper level flow pattern with sharp ridge over
the nations mid section building east into the Great Lakes by
Thursday morning. At the surface, weak trof over southern Ohio to
continue dropping south with high pressure building across the
region, becoming centered over western PA by morning.
Latest visible satl imagery shows low clouds just to our north,
dissipating. In waa pattern expect this trend to continue with
skies mainly clear through most of the night. Some valley fog will
be possible in protected locations. High level clouds to increase
late as they spill in from the west. With winds coming around to
the southeast, temperatures will be a little milder tonight,
especially in the western counties. Expect lows to range from the
mid 30s east to the lower 40s west.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
Mid/upper level ridge to build over the area Thursday. On the back
side of retreating surface high pressure a southerly gradient will
increase during the afternoon. Expect only some high level clouds
during the day. Sunshine and a southerly flow will allow
temperatures to warm close to 20 degrees above normal. Expect
highs to range from the mid 60s northeast to the lower 70s
southwest.
Mild and dry night for Thursday night with a southerly low level flow
continuing. Expect lows from the lower 40s far east to 50 west.
Mid/upper level flow to back southwesterly as ridge shifts to the
east coast and trof moves into the plains. As the trof moves into
the Great Lakes, associated surface cold front to sweep east
across ILN/s FA Friday night. Expect Friday to be dry with an
increase in clouds late. On the warm side of the front, expect
continued highs close to 20 degrees above normal. Fridays highs to
range from near 70 northwest to 75 southeast. As the gradient
increases southerly winds will gust up to 35 mph Friday afternoon
into Friday night.
A thin ribbon of weak instability will exist invof the front in
the early evening across the far west but then quickly diminishes.
Sherb parameter pointing to the potential for QLCS event in our
west early Friday evening. Will have to watch future model runs
as we get closer to the event. Will continue to go with high
likely pops Friday night. Strong caa will drop temperatures to
lows from the upper 30s west to the lower 40s east. Rain will
mix with and change to snow showers toward sunrise Saturday.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
old front will be east of ILN Saturday, with the area under a brisk
northwest flow. Rain showers will mix with snow showers, possibly
producing light accumulations north of the Ohio River. Wind gusts to
40 mph are expected. Snow shower chances will linger Sunday,
especially over northeast locations that will be closer to departing
moisture and short wave energy.
Monday should have dry weather with high pressure centered to the
northwest, though clouds may linger in a cyclonic low level flow.
Low pressure developing to the west will begin to affect the area on
Tuesday with increasing clouds and a low chance for showers. Models
differ with respect to timing for this system, with the ECMWF
offering a slower solution. A chance of showers will extend through
Wednesday when the low and a cold front will be crossing the region.
Temperatures will be below normal Saturday and Sunday due to strong
cold advection, with highs in the upper 30s to around 40. Went below
guidance that appears to be too warm for this weather regime. A
rebound to normal readings around 50 is expected by Tuesday and
Wednesday in warm advection associated with the low.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Fog will be the main focus for the overnight forecast, with MVFR
visibilities likely to develop for most of the TAF sites. There is
a chance of IFR conditions, but the probability is too low to
include in the forecast. KLUK is likely to experience LIFR
conditions for most of the night.
Winds tomorrow will increase from the south-southeast, at around
10-12 knots during the afternoon. Cirrus clouds will move into the
region, and VFR conditions are expected.
OUTLOOK...MVFR ceilings and visibilities are possible from Friday
night into Saturday morning, with MVFR ceilings possibly
continuing into Saturday afternoon. Wind gusts of 25 to 30 knots
can be expected Friday afternoon, with wind gusts of 30 to 35
knots on Saturday afternoon.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...Dense Fog Advisory until 8 AM EST Thursday for OHZ026-035-
044>046.
KY...None.
IN...None.
&&
$$
SYNOPSIS...AR
NEAR TERM...Hatzos/AR
SHORT TERM...AR
LONG TERM...Coniglio
AVIATION...Hatzos
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
534 PM CST Wed Nov 16 2016
.UPDATE...
Issued at 535 PM CST Wed Nov 16 2016
Updated to include 00Z aviation discussion below.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 339 PM CST Wed Nov 16 2016
Surface analysis this afternoon shows extensive high pressure
over the Great Lakes and southeastern CONUS while a
conglomeration of surface low pressure centers exist over the
Northern Plains into the Central Rockies. Out of one low pressure
center, the main one which will impact the region through tomorrow
afternoon located over central South Dakota, its leading warm
front extends SE into eastern Nebraska through northern Missouri.
Aloft, a large ride axis extending from the western GOMEX to the
southern tip of Hudson Bay continues to slowly drift east while a
potent longwave trough moves onshore the California coast. It is
this trough which will be a major player in the significant winter
storm which will impact the area Friday. Before that point, the
exiting high pressure will maintain its influence over the area
this evening into the early morning hours by keeping partly cloudy
skies in place with southeasterly winds. During the overnight
period, the warm front to the southeast will steadily lift north,
dragging higher amounts of moisture with it into the region. As
the warm front approaches, winds will switch to NNE, which will
force the low level moisture to be realized as low stratus by
daybreak tomorrow. The low clouds will then remain in place
throughout the day. The temperature profile for tomorrow will be
heavily dependent on how far north the warm front shifts, and its
associated low clouds. At this point, have opted to keep the
highest temperatures well in the southeastern portion of the WFO
MPX coverage area with cooler temperatures northwest, to a nearly
20-degree gradient for high temperatures over the area. As for
precipitation, Will look for rain to move in from the west as the
stronger trailing surface low develops deeply in advance of the
aforementioned strong trough aloft. No p-type issues are expected
through tomorrow afternoon. In fact, there is the possibility of
having -DZ develop from late morning through tomorrow afternoon
before the heavier precipitation moves in as the moisture column
slowly deepens in advance of the warm front. Confidence not great
in this scenario so have left -DZ out at this point but the
possibility cannot be discounted altogether.
.LONG TERM...(Thursday night through Wednesday)
Issued at 339 PM CST Wed Nov 16 2016
...BLIZZARD CONDITIONS BECOMING INCREASINGLY LIKELY FRIDAY ACROSS
WESTERN MINNESOTA...
Confidence remains high on a winter storm affecting a good portion
of western, central, and northeast Minnesota with heavy snowfall
amounts from Thursday night, and into Friday evening.
Censuses among the individual ensembles and operational runs
remain close for a high probability of a heavy snowfall band
along and northwest of a surface low that will track across the
Plains, and Upper Midwest late this week. Current models have this
area of low pressure tracking from far northwest Iowa/southwest
Minnesota Thursday evening, northeast to the UP of Michigan by
Friday afternoon.
The combination of a rapidly strengthening pressure gradient late
Thursday night/Friday morning has surface winds increasing from
around 20 to 25 mph sustained Thursday evening, to 30 to 40 mph
sustained, along with gusts of 40 to 60 mph in the blizzard watch
area, by sunrise Friday. Although the snowfall will be very wet
and heavy once the change over occurs, snowfall rates could be as
high as 2 inches per hour, limiting visibility to less than one
quarter of a mile. Thus, the combination reduced visibility and
high winds, will create the blizzard conditions. Further to the
east, snowfall rates will be less intense, but high enough to
warrant a winter storm watch. Based on the track of the surface
low, and a very strong thermal gradient along it, snowfall
amounts will quickly lower to less than an inch or two in the warm
sector once the change over to snow occurs. Depending upon
residual moisture wrapping around the strong storm Friday
afternoon/evening, a quick one or two inches of snow will be
possible in south central and east central Minnesota, as well as
west central Wisconsin. As with these type of systems, the
gradient between a foot of snow, to only a dusting could be as low
as 50-100 miles.
Beyond Saturday, and how the mean weather pattern has been mild
with an upper ridge centered across the central U.S., any snow
on the ground will begin to melt the following week. It won`t be
as mild as it has been, but the above normal temperature regime
pattern will continue through Thanksgiving.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 535 PM CST Wed Nov 16 2016
We should see a steady increase and lowering of cloud cover
through the period, with MVFR and possible IFR looking to hold off
until the daytime hours for the most part. We may see some
visibility restrictions over the eastern sites late tonight and
Thursday morning, where there will be a bit of enhanced low-level
moisture near the axis of the inverted through that looks to setup
overnight and remain in place until the surface low eventually
works its way northeast along that gradient in temperature. As far
as precipitation goes, at this point it looks to hold off, with
the exception of perhaps some drizzle, until the tail end of the
period and that will be mainly in the northwest portion of the
area.
KMSP...Main items of uncertainty in the forecast are the timing of
the arrival of MVFR ceilings and whether we`ll see any prolonged
IFR ceilings. For now, stayed slightly on the optimistic side,
pushing back the arrival of MVFR conditions some. But, timing of
things could certainty vary by several hours, so will need to keep
an eye on observations and latest guidance. In addition, should
continue to have some LLWS concerns this evening as the low-level
jet intensifies. It looks to relax overnight based on the latest
RAP guidance.
/OUTLOOK FOR KMSP/
Thursday overnight...MVFR expected, IFR possible. Rain. Northeast
wind 10 to 15 kt becoming east.
Friday...MVFR expected, IFR possible. Rain changing to light snow.
East wind 10 to 20 kt shifting northwest 20 to 30 kt.
Friday night...MVFR. Light snow ending. Northwest wind 20 to 30
kt.
Saturday...VFR. Northwest wind 15 to 25 kt decreasing to 5 to 15
kt.
Saturday night...VFR. Northwest wind 5 kt or less becoming
variable.
Sunday...VFR. Southeast wind 5 to 10 kt increasing to 10 to 15 kt.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...Blizzard Watch from late Thursday night through Friday evening
for MNZ041-047-048-054>056-064.
Winter Storm Watch from Friday morning through Friday evening
for MNZ042-043-049-050-057-058-065-073.
&&
$$
UPDATE...
SHORT TERM...JPC
LONG TERM...JLT
AVIATION...
Area Forecast Discussion
National Weather Service Phoenix AZ
450 PM MST Wed Nov 16 2016
.SYNOPSIS...
A low pressure system will begin moving through the western states
through Thursday. This will result in breezy to windy conditions and
much cooler temperatures, most noticeably on Thursday when highs in
the low deserts will be around 70 degrees. The coolest morning so
far this month will be on Friday. A warming trend is expected over
the weekend. A weather system may bring unsettled conditions with
chance of showers mainly across south central Arizona by the
beginning of next week.
&&
.DISCUSSION...
Widespread mid and high clouds continue to stream northeastward
ahead of a broad trough extending from the Pacific Northwest into
central California. The clouds have inhibited insolation this
afternoon, resulting in temperatures generally in the upper 70s and
lower 80s across the lower deserts. Meanwhile, the lower levels of
the atmosphere remain relatively dry with dewpoints in the 20s and
30s.
Short-term models remain in good agreement that a clearing trend
from west to east will take place overnight behind the eastward-
advancing trough axis. Low-level pressure gradient will also tighten
behind a frontal boundary, producing breezy conditions across
portions of southeastern California and southwestern Arizona. Latest
runs of the HRRR indicate wind gusts in these areas may reach 25 to
30 mph, particularly across ridgetops including JTNP.
&&
.PREVIOUS DISCUSSION...
Over the past several days, the operational GFS has been sort of a
yo-yo with respect to the approaching Pacific trof, at times digging
it further south into central/southern Arizona with strong winds and
sharp cooling, then alternating with more of a brush-by, with lighter
winds and less cooling and little or no threat of precip over the
southern half of the state. GEFS ensemble members were always a mixed
bag with the strength of this system. ECMWF has typically been a bit
weaker with the brunt of the trof passing by to our north, and the
latest few GFS operational runs have come into a good
alignment/agreement with the ECMWF. As such, we are expecting a fast
moving Pacific trof to push east across the area tonight through
Thursday evening with the main weather impacts being breezy/windy
conditions (mainly over the western deserts and favored areas of
southeast CA) and marked cooling.
High temps Thursday should lower into the upper 60s to low 70s over
most of the lower deserts and Phoenix should see the high fall to 71
degrees (4 degrees below normal). For now we will keep our winds
mostly below wind advisory thresholds, except for a few spots over
ridgetops and open country across favored areas of southeast
California such as Joshua Tree National Park. There may be a few
winds gusts to around 40 mph Wednesday night over the western deserts
and far southeast CA but we will not be issuing a wind advisory for
this system at this time due to borderline conditions.
Dry subsident northwest flow aloft will quickly spread in from the
west Thursday night into Friday as a flatter upper ridge builds into
the area, leading to sunny skies and slight warming. High temps
should climb to near seasonal normals on Friday over the deserts.
High pressure aloft will continue through the day on Saturday
allowing for a continued modest warming trend where the lower
deserts climb into the upper 70s to lower 80s under sunny or mostly
sunny skies.
The progressive nature of the flow pattern will lead to yet another
sharp change in the weather for the desert southwest late this
weekend and into early next week as another fast moving but much
wetter Pacific low appears poised to race through the area bringing
scattered showers along with considerable clouds and cooling. As the
trof sharpens up just off the California coast Sunday, the southwest
flow ahead of it taps into some subtropical moisture and sends quite
a bit of mainly high clouds into the state. By Monday morning, the
trof axis will be moving inland along the far northern Baja/southern
CA coast, with strong upper difluence and PVA moving into southern
Arizona. PWAT values are progged to climb over one inch across south
central Arizona, and these values will rise above the 90th
percentile of climo as shown by the situational awareness table
guidance. Operational runs of the GFS and ECMWF are very similar and
are trending wetter with this next system and the latest MRAMOS
guidance for Phoenix has climbed to 88 percent for Monday.
NAEFS POPs are also climbing and with values in excess of 50 percent
over much of south central AZ by Monday afternoon. As a result we
have raised our POPs sharply on Sunday night and Monday, with values
into the likely category over the higher terrain east of Phoenix by
Monday. Given the clouds and high chances for showers, high temps
will cool sharply and we have this reflected in our max temp
forecasts. At this time we are going with a high of 70 for Phoenix
on Monday but we may well see readings falling into the 60s should
the showers pan out.
As the system quickly races off to the east Monday night into
Tuesday we can expect a marked drying trend from the west; by
Tuesday afternoon there will be just a lingering slight chance of
showers over the higher terrain east of Phoenix with skies becoming
mostly sunny over the western lower deserts.
&&
.AVIATION...
South-Central Arizona including KPHX, KIWA, and KSDL:
Broken to overcast mid and high clouds across the area will persist
for the remainder of this evening then quickly clear overnight.
Westerly winds will persist for most of the forecast period, though
some brief southeasterly winds will be possible this evening. Given
current trends though expect winds to be light from the west for the
evening push. Reinforcing westerly winds, with a few gusts into the
teens at times, develop tonight as skies clear and persist into
tomorrow.
Southeast California/Southwest Arizona including KIPL and KBLH:
Broken to overcast mid and high clouds across the area will persist
for the remainder of the day before clearing out tonight. As a dry
strong frontal system sweeps through the area, gusty westerly winds
will develop. Gusts will top into the 20-25kt range, but with the
timing overnight won`t be surprised to see periods with lower values
as terrain shields the winds. Northerly winds remain into Thursday.
Aviation discussion not updated for amended TAFs.
&&
.FIRE WEATHER...
Friday through Tuesday:
Fairly cool temperatures to persist into Friday (highs in the 70s
over the lower deserts) followed by warming for this weekend.
Humidities will be quite low through the weekend with afternoon
minimum values between 10-20 percent over the lower deserts. Winds
will be light Friday through Sunday with occasional afternoon
breeziness. A weather system approaching from the west will lead to
continued increasing humidity on Monday along with a good chance of
wetting rains across the area. This system will bring another shot of
cooler air with temperatures back to near normals for Monday and
Tuesday.
&&
.SPOTTER INFORMATION STATEMENT...
Skywarn radio Net activation will not be needed through Sunday.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
Visit us on Facebook...Twitter...and at weather.gov/phoenix
DISCUSSION...Hirsch
PREVIOUS DISCUSSION...CB
AVIATION...Iniguez/Hernandez
FIRE WEATHER...Kuhlman
Area Forecast Discussion
National Weather Service Taunton MA
421 AM EST Thu Nov 17 2016
.SYNOPSIS...
High pressure slowly building in from the west will bring dry and
mild weather through Friday. Strong low pressure will push across the
region this weekend, bringing periods of rain showers. As colder
air moves in, any leftover precipitation will mix with or change
to snow showers Sunday night. Below normal temperatures expected
through Tuesday, then warm towards normal mid-week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Localized patchy ground fog in the typically prone locations of
interior southern New England will burn off shortly after sunrise.
Otherwise, vigorous upper level energy will move across eastern New
England this morning. Low level forcing is extremely limited and
moisture is quite shallow, but can not rule out a few brief light
showers/sprinkles across eastern MA this morning. The latest runs
of the HRRR and RAP actually show this possibility towards 12z, so
did include some very low pops.
Model cross sections indicate a fair amount of low level moisture
lingering across eastern New England through the afternoon.
Therefore, expect clouds to dominate across eastern MA/RI but some
peeks of sun are still expected. Meanwhile, partly to mostly sunny
skies are anticipated across western MA/northern CT.
High temps will range from 55 to 60 across most of the area this
afternoon. Mildest readings expected in the Lower CT River Valley,
where more sunshine is expected.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
Tonight...
Drier air working in from the north should result in skies becoming
mostly clear across a good portion of southern New England. The
exception will be across the Cape/Islands where some clouds will
linger from a distant ocean storm. Low temps will bottom out around
30 across the normally coolest outlying locations of western MA, to
between 40 and 45 across downtown Boston and Providence.
Friday...
Upper level ridging nosing into southern New England from the
southwest will result in a beautiful day for mid November standards.
Expect plenty of sunshine after any lingering clouds depart the
Cape/Islands during the morning. Anomalous mid level warmth should
allow high temperatures to recover into the lower 60s across much of
the region. The exception will be the southeast New England coast
where gusty northerly winds from a distant ocean storm will hold
high temps in the middle to upper 50s.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Highlights...
* Mild temperatures expected Friday night and Saturday
* Low pressure Sat night & Sun will bring periods of rain showers
* Much colder temps Sun night, change rain to snow showers
The 17/00Z models are in decent agreement through much of the long
term. There are some issues in the guidance and of course as you
get later into the period there are more discrepancies. The ECMWF
is deeper and slower with many of the features than the GFS. The
Canadian leans towards the ECMWF but has been inconsistent. Have
used a blend of the ECMWF and GFS guidance for much of this
forecast.
Friday night and Saturday...An upper level ridge and accompanying
surface high pressure over southern New England Friday night will
move offshore Saturday. Mild temperatures are expected during this
time with high temperatures in the mid to upper 50s.
Saturday night and Sunday...A strong upper trough moves into the
northeast, becoming negatively tilted. Low pressure moves out of
the Great Lakes into Quebec, with a secondary low developing over
southern New England and moving into the Maritimes. This will bring
periods of rain showers to the area. The most consistent period of
showers will be Saturday night and Sunday, though showers may linger
through Sunday night. Temperatures drop through Sunday and Sunday
night, eventually allowing these lingering rain showers to change to
a mix of rain and snow or all snow showers. There`s not a lot of
QPF expected with these showers, so not expecting much in the way of
accumulation of snow.
Monday and Tuesday...Dry, but much colder weather is expected during
the early part of the week on northwesterly flow. Temperatures will
fall below normal, with the coldest temperatures on Monday.
Wednesday...There are indications of an area of low pressure
approaching southern New England that would bring stormy conditions
to the region. However, given the time frame, there is a lot of
uncertainty regarding this potential.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
Forecaster Confidence Levels.
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Short Term /through Friday/...
Today...High confidence. Any localized patchy ground fog across the
interior will burn off by mid morning. Otherwise, a broken deck of
mid level cloudiness will mainly affect the eastern half of southern
New England today. CIGS will generally remain VFR, but brief periods
of MVFR CIGS can not be ruled out.
Tonight and Friday...High confidence. Mainly VFR conditions with
just a low risk for brief MVFR CIGS tonight across Cape/Islands.
Northerly wind gusts of 20 to 30 knots develop across the
Cape/Islands toward daybreak Friday and continue through Friday
afternoon.
KBOS TAF...High confidence in TAF. Despite a broken deck of mid
level cloudiness today expect VFR conditions to dominate, but brief
marginal MVFR CIGS can not be ruled out.
KBDL TAF...High confidence in TAF.
Outlook /Friday Night through Monday/...
Friday night through Saturday...High confidence. Mainly VFR. Areas
of patchy fog may result in MVFR/IFR conditions Friday night into
early Saturday morning.
Saturday night through Sunday...Moderate confidence. Mainly VFR.
Periods of rain showers and fog may result in brief MVFR/IFR
conditions. Rain showers may change over to snow showers Sunday
night as colder air moves in.
Monday...Moderate confidence. VFR.
&&
.MARINE...
Forecaster Confidence Levels.
Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.
Short Term /through Friday/...High confidence.
Today...High confidence. North to northwest wind gusts up to 20
knots are expected today, but conditions should remain below small
craft advisory thresholds.
Tonight and Friday...High confidence. Intensifying ocean storm and
high pressure to our west will result in an increasing pressure
gradient tonight into Friday. Expect northerly wind gusts of 20 to
30 knots to develop with the strongest of those winds expected to be
southeast of Nantucket. Small craft headlines posted for most open
waters with seas expected to build to between 5 and 9 feet across
our eastern outer-waters.
Outlook /Friday Night through Monday/...
Friday night and Saturday...Seas diminish slowly as high pressure
moves across the waters, but remain above 5 feet on the outer waters
for much of that time.
Saturday night and Sunday...Winds and seas increase as low pressure
develops over southern New England. Small craft advisories will
likely be needed.
Monday...Winds and seas will remain elevated with a tight pressure
gradient over the waters. Small craft advisories are likely to
continue.
&&
.TIDES/COASTAL FLOODING...
Today...Astronomical high tide at BOS is 12.1 ft at 1253 pm.
ESTOFS/ETSS surge forecast is near zero and with limited wave action
nothing more than some very minor splash over expected in the most
vulnerable locations. No headlines are needed.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory from 8 PM this evening to 7 PM EST Friday
for ANZ231>235-251.
Small Craft Advisory from 6 PM this evening to 7 PM EST Friday
for ANZ250-254.
Small Craft Advisory from 10 PM this evening to 7 PM EST
Friday for ANZ255-256.
&&
$$
SYNOPSIS...Frank/RLG
NEAR TERM...Frank
SHORT TERM...Frank
LONG TERM...RLG
AVIATION...Frank/RLG
MARINE...Frank/RLG
TIDES/COASTAL FLOODING...Frank
Area Forecast Discussion
National Weather Service Dodge City KS
337 AM CST Thu Nov 17 2016
.SYNOPSIS...
Issued at 248 AM CST Thu Nov 17 2016
A strong upper level storm system will approach the high plains
today and then eject into the upper midwest by Friday. A cold
front will slip southward through Garden City and Dodge City to
the Oklahoma state line this morning system since the upper level
system is still digging east-southeastward. This front will move
back to the north as a warm front this afternoon as the upper
level trough becomes negatively tilted and approaches the high
plains. A north to south oriented front cold front will push
eastward into western Kansas toward evening. How far north the
warm front gets through 5 pm will determine fire weather
conditions and strength/direction of low level winds. After this
system passes this evening, colder air will surge into western
Kansas with the coldest air of the season. Upper level ridging and
lee troughing will commence over the western high plains by
Saturday and persisting through Sunday and early Monday. The next
upper level trough will approach the high plains by Monday night
and Tuesday.
&&
.SHORT TERM...(Today and tonight)
Issued at 248 AM CST Thu Nov 17 2016
Temperatures will be tricky today given the early morning cold frontal
passage and late afternoon warm frontal surge. The warm surge may
occur after peak heating so that locations such as Jetmore and
Garden City may not get into the warm and dry sector. There may be
a sharp gradient in temperatures this afternoon from upper 50s to
near 60 at Wakeeney to near 80 at Englewood and Liberal. Winds may
approach high wind warning criteria from Elkhart to Liberal this
afternoon since RAP soundings indicate deep mixing up through
700mb with 50 kt winds at that level. Much cooler air can be
expected by late tonight.
.LONG TERM...(Friday through Wednesday)
Issued at 248 AM CST Thu Nov 17 2016
A slow warming trend can be expected Saturday through Monday ahead
of the aforementioned upper level trough. There are small chances
for rain showers Monday night into Tuesday as low level moisture
increases ahead of the system; and a short-lived cool down is
expected by Tuesday in the wake of the system.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1156 PM CST Wed Nov 16 2016
A weak cold front will approach this morning and then return as a
warm front this afternoon. Surface low pressure will develop over
western Kansas this afternoon as a stronger cold front
approaches. This cold front will pass tonight in the wake of the
shortwave trough, along with 20kt northwest winds.
&&
.FIRE WEATHER...
Issued at 707 PM CST Wed Nov 16 2016
The only county to be removed from the red flag warning is
Hodgeman since the warm front is not expected to progress that far
north this afternoon. Finney and Ford counties may also be too far
north for critical fire weather conditions to be met for 3 hours.
High winds and very low humidity will lead to the most favorable
conditions for wildfires from Stanton and Morton counties eastward
to Seward county.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 73 34 48 22 / 0 10 0 0
GCK 70 33 46 19 / 10 20 0 0
EHA 72 30 47 21 / 0 10 0 0
LBL 78 32 50 20 / 0 0 0 0
HYS 63 36 46 22 / 10 20 0 0
P28 77 41 52 26 / 0 10 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 11 AM CST /10 AM MST/ this morning to 7 PM
CST /6 PM MST/ this evening for KSZ061>063-074>078-084>088.
&&
$$
SYNOPSIS...Finch
SHORT TERM...Finch
LONG TERM...Finch
AVIATION...Finch
FIRE WEATHER...Finch
Area Forecast Discussion
National Weather Service Grand Forks ND
349 AM CST Thu Nov 17 2016
.SHORT TERM...(Today and tonight)
Issued at 254 AM CST Thu Nov 17 2016
What happens at the start of the watch period late tonight will
be the main headache for the short term.
The upper trough currently digging into the Desert Southwest will
move into CO/KS by the end of the day. The surface trough
currently extending from KS up into southern MN will deepen, with
cold air advection on the northwest side of it. By this evening,
all but the far southeastern counties will see 925mb temps below
zero C. Lowered highs just a bit across the west where cold air
advection will make it difficult to get out of the 30s, with 40s
in the east. Models start mid level frontogenesis over our
southern counties by this afternoon, and several put out some
light QPF although the HRRR and RAP keep anything from reaching
the ground until later this evening. Will continue the trend of
slowly ramping up POPs this afternoon. Mostly rain, although some
snow mixing in is possible across the western edge towards sunset.
Tonight, the upper trough begins lifting towards the upper
midwest, with the surface low closing off and reaching the IA/MN
border by 12Z. The first frontogenesis band starts to diminish
late tonight, but even stronger frontogenesis gets going a bit
further east and is well correlated with strong Q vector
convergence. There continues to be minor variations in the exact
track of the system which have big impacts on how much snow falls
across our southern and eastern counties. With high levels of
uncertainty will hold off on any upgrades to headlines and keep
things as a watch for now.
.LONG TERM...(Friday through Wednesday)
Issued at 254 AM CST Thu Nov 17 2016
Friday...The upper trough will lift into northeastern MN, with the
strong surface low tracking into the Great Lakes and putting MN
in the cross hairs for the deformation zone snow band. With some
frontogenesis there is also banding potential and it is difficult
at this point to tell where that will exactly end up. SREF plumes
for Fargo have snow totals by the end of the day Friday ranging
from just over half an inch to around 20 inches. Several of the
most recent model runs have been trending further east with the
main precipitation band, but there are still ensemble members
dropping quite a bit of QPF over southeastern ND into northwestern
MN. With high uncertainty still will keep headlines in the watch
phase. What is more certain is wind. With the track of the surface
low the tight gradient will be right over our southern counties.
925mb winds will be pushing 50 kts and 850mb winds will be even
higher. Bumped up winds above the blended solution and have gusts
in the far southeast above 45 kts at times Friday. Temps across
the southeastern counties will see a midnight high with readings
steady or slowly falling into the low 30s.
Saturday to Wednesday night...
Overall dry period with minimal weather impacts and much cooler than
the first half of the month with highs generally in the 30s and lows
in the teens and 20s. The exception will be if and where deep snow
pack develops with Friday storm system. Temps above the snowpack
will have a hard time warming and will cool more readily at night
than snow free areas. Sunday will be the first morning with little
mixing and few clouds so expecting temps over the snow pack to drop
into the low teens if not further. The rest of the week will see a
slow moderation and a shot at 40 degrees by Thanksgiving day.
500MB NW flow with SFC high pressure across the northern plains will
gradually give way in the progressive flow aloft to the next short
wave moving across the central plains on Monday night into Tuesday.
Will keep PoPs limited to the far eastern portions of the FA for
Tuesday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1136 PM CST Wed Nov 16 2016
The northwest winds are coming in quicker than anticipated, and
have reached all TAF sites but KBJI. The wind switch should come
just after midnight for KBJI. Otherwise the MVFR clouds are within
a few hours of reaching KDVL. These MVFR clouds will spread SE and
reach all the other TAF sites by morning. The NW to N winds will
become gusty by Thursday morning, with the strongest gusts coming
by mid to late morning and continuing into Thursday evening. Some
light pcpn should begin to affect KFAR and KBJI early Thursday
evening. It may start out as rain, but should mix with or change
to snow. The heavier pcpn and any potential vsby restrictions
will be more likely after this TAF period.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Winter Storm Watch from late tonight through Friday afternoon
for NDZ039-049.
Blizzard Watch from late tonight through Friday afternoon for
NDZ052-053.
MN...Winter Storm Watch from late tonight through Friday afternoon
for MNZ002-003-006-009-015>017-022>024-027-028-032.
Blizzard Watch from late tonight through Friday afternoon for
MNZ029>031-040.
&&
$$
SHORT TERM...JR
LONG TERM...JR/JK
AVIATION...Godon
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
327 AM CST Thu Nov 17 2016
.SHORT TERM...
321 AM CST
Through Tonight...
Today we ascend what will be a 48-hour roller coaster temperature
ride with near-record warmth this afternoon. Regarding impacting
weather, wind gusts will be on their way up today, though still
be a fair amount short of advisory criteria.
Low pressure around 997 mb will basically remain in place today
near the NE/IA border with its warm front lifting over the area
late this morning. Impressive 925mb warmth of 22C was observed at
KSGF last evening reflective of the warm maximum that will
translate northeastward with the front. The 925mb temperatures
should peak at 18-20C over the CWA using a nudge up above a
guidance blend, and that is basically record territory for mid-
November. Chicago ORD averages a high of 71 when 925mb
temperatures reach that high in November using the NARR (North
American Regional Reanalysis). The only concern from not reaching
into these 70s would be the cirrus. The RAP 300mb humidity
forecast has a good handle on present cirrus and its evolution
matches upstream water vapor imagery, indicating a thin but at
times broken cirrus over much of the CWA today. Advection will
play a greater role than solar warming, but still the cirrus
could rob a couple degrees from forecast highs in the north. See
Climate discussion below for more on records.
Wind gusts will increase to 25-30 mph, maybe a tad higher, behind
the warm front as projected by modified NAM/GFS soundings. These
gusts will likely just continue through the entire night, likely
just a little less frequent. This will ensure a very mild night,
with lows 5-8 degrees above normal high temperatures this time of
year.
MTF
&&
.LONG TERM...
321 AM CST
Friday through Wednesday...
We will remain at the peak of the temperature roller coaster
Friday morning before a sharp descent that will continue into
Saturday with little temperature recovery this weekend. The main
weather message along with this first cold punch of the season is
the winds, which at times later Friday through the day Saturday
very well could gust to 40+ mph. A Wind Adviosry may be needed by
the next shift.
The key features and mass fields of this classic late autumn
system have wobbled very little in guidance the past 24-hours
with just some slight slowing of the envelope of solutions. The
low should be around 996 mb over western Wisconsin by midday
Friday, favoring a pronounced warm sector over the CWA through
early afternoon. Have nudged up highs in eastern areas toward 70
given strong warm advection and such a warm starting point to the
day. The stout cold front is presently forecast to pass west-to-
east through the CWA in the 12-5 p.m. period. Have used raw
guidance for the hourly temperatures to note what should be a
constant but notable drop from fropa through the evening.
Wind gusts look to be at their peak in the several hours
immediately behind the cold front, where unidirectional southwest
flow aligns with strong cold advection and a high isallobaric
component. Top of the channel winds are 45-50 mph on the NAM and
GFS, especially in the northern half of the CWA. Gusts will remain
30+ mph and possibly 40+ mph at times through the night.
Besides these gusts being realized in the window of time after
fropa, any showers or thunderstorms ahead of the front during the
afternoon could also tap these high top of the channel synoptic
winds. Showers and convection are most favored along/east of I-55
as the mid-level jet and associated lift wrap around the upper
trough and overlay the front and the narrow moist tongue. Again
the severe threat is low, but with these type of fronts there can
be isolated near-severe gusts even without lightning being
present.
Model differences for wraparound flurries or light snow shower
potential overnight Friday and Saturday morning does vary, but do
see a decent potential to rattle out at least scattered, wind-
blown, light precip...especially over the northern CWA. Using the
Bourgouin precipitation-type technique, mainly the low- level
positive energy with respect to wet bulb, the profiles are cool
enough for snowflakes in north central Illinois already by early
overnight Friday and in Chicago by daybreak Saturday. Not
expecting any accumulation with any of this, but if some true snow
showers materialize it is possible to get some sharply reduced
visibility due to the wind combination.
Wind gusts will gradually ease Saturday afternoon as the low pulls
away and more so later Saturday night. Temperatures during the day
will struggle to rebound much if at all past the upper 30s, with
lows in the lower to mid 20s for many locations. Gradually veering
lake effect flow will likely support showers into northeast
Porter County in Indiana Saturday night into Sunday morning. The
depths of the clouds will be shrinking due to drying aloft, so
not expecting anything big, but if indeed the showers do occur,
some of that likely will be snow.
High pressure will prevail Sunday-Monday, with a chilly night in-
between due to the light winds and forecast clear sky. Some of the
first teens of the year are likely in favored outlying locations.
Looking ahead toward the holiday week, the next system is showing
decent predictability in global guidance in terms of timing and
the Midwest being impacted with precipitation Tuesday-Wednesday.
The past 24-hours have shown a slight northwest trend with this,
but that`s well in the envelope of uncertainty still, so made
little changes in the blended solution. Have rain showers likely
through a good portion of Tuesday into Wednesday. Right now this
system is progressive enough not to drag in too cold of air while
forcing for precip is present. However, there still could be some
travel impacts with wind-whipped rain and low clouds on
Wednesday, and obviously more so if the systems shifts a tad
further south (meaning cooler temperatures).
MTF
&&
.CLIMATE...
321 AM CST
Temperatures are forecast today to be within a few degrees of
record highs, and cannot rule out reaching them.
Record Highs for Thursday, November 17:
Chicago: 74 (1975)
Rockford: 73 (1941)
The normal last 70 degree day at Chicago is October 30, and there
have been just five years in the past 40 with a 70 degree day
after the midpoint of November. The normal last 70 degree day at
Rockford is October 27, and there has only been one year (1999) in
the past 40 with a 70 degree day after the midpoint of November.
The latest 70 degree day at Rockford on record is November 21,
1913.
MTF
&&
.AVIATION...
For the 06Z TAFs...
Primary Concern: strong southerly winds and LLWS
Surface high pressure from the Central Great Lakes to the Gulf
Coast will continue to shift east early this morning as low
pressure over western Kansas strengthens and tracks northeast. In
response, strengthening south-southwest winds aloft will set up a
period of LLWS this morning. 40-45 kt winds can be expected
between 1000-1500 feet AGL, with the LLWS arriving first at RFD
and then spreading east.
Southerly surface winds will then quickly increase by the mid
morning today. Peak gusts will depend on mixing depth, but based
off very warm air temperatures forecast, we should be able to tap
into the ~25-30 kt winds at 1000 feet or less AGL. Thus bumped up
gusts in the TAF for late morning-afternoon period and am
concerned gusts could even top 30 kt at times. Direction will be
primarily range from 180-190 degrees during peak winds, so if the
higher gusts materialize, cross wind issues are possible on east-
west runways. It is a bit uncertain exactly how much gustiness
will linger Thursday evening, but despite this, another period of
LLWS is likely as winds around 2000 feet AGL increase to 50+ kt.
Confidence is medium in the wind forecast and medium-high in the
LLWS forecast.
Conditions will be primarily VFR this TAF period, with high
confidence in this during the day today into tonight. ORD/DPA/GYY
had dropped to MVFR VSBY Wednesday evening, and it`s still possible
they briefly drop to high end MVFR over the next few hours.
Castro
&&
.MARINE...
221 AM CST
The main forecast concerns during the period continue to focus on
a strong storm system expected to have a major impact on the
Great Lakes Friday through Sunday.
A significant Autumn season storm system is will impact the Upper
Midwest and Great Lakes region through Sunday. Initially, the
winds should be increasing out of the south over the lake
today as the storm system take shape across the Central Plains.
However, on Friday as the storm system strengthens over the Upper
Mississippi Valley, south to southwesterly winds will likely
increase to 35 KT Gales during the day. The low pressure area is
then forecast to shift northeastward over the Upper Lakes region
into Saturday morning. As it does so, a strong cold front will
sweep eastward over the lake sometime late Friday or Friday
evening. Winds will then likely become westerly and increase more
into the high end gale category up to 45 KT by Saturday as much
colder air spills over the lake on the back side of the low. Given
the strength of this storm system, there could also be a period of
near 50 KT Storm force winds on Saturday over northern Lake
Michigan as strong pressure rises overspreads the lake on the
back side of the low. Gale force winds could continue into early
Sunday before abating.
Given the high impact/high confidence forecast of gales on the
lake, we have opted to go ahead and issue the gale warning for the
entire lake, including the IL and IN near shore waters, from
midday Friday through Sunday morning. The strongest winds are
likely Friday night into Saturday. There is also the possibility
that an upgrade to a storm warning may be needed for northern Lake
Michigan for Saturday. However, at this time, we felt it prudent
to get the warning out as at the very least it will be a high end
Gale event.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...Small Craft Advisory...NEARSHORE WATERS
UNTIL NOON Friday.
Gale Warning...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...NOON
Friday TO MIDNIGHT Sunday.
Gale Warning...LMZ777-LMZ779...NOON Friday TO 9 AM Sunday.
&&
$$
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Area Forecast Discussion
National Weather Service Marquette MI
459 AM EST Thu Nov 17 2016
.SHORT TERM...(Today and tonight)
Issued at 453 AM EST THU NOV 17 2016
WV imagery and RAP analysis indicated a mid/upper level trough over
the wrn CONUS with a vigorous shortwave moving into sw Utah and a
ridge from the lower MS valley to the cntrl Great Lakes. At the
surface, southerly flow was increasing between a trough from n cntrl
KS to ne MN and high pressure over the ern Great Lakes. IR loop
showed increasing mid/high clouds with the WAA pattern over the
region. The sse flow has also brought increasing low level
moisture/clouds, aided by Lake Michigan, into cntrl Upper Michigan.
Today, despite thickening cloud cover, WAA will be strong enough to
boost temps from early morning readings in the mid 50s to max temps
in the lower to mid 50s.
Tonight, pcpn increasing with 300k-305k isentropic lift along the
strengthening 850-700 mb front from wrn Lake Superior into ne MN is
expected to gradually sag into the wrn cwa. Rain will become likely
over the far west from IWD to CMX with chance pops over the rest of
the nw half of the cwa. Otherwise, temps will remain well above
normal with lows into the 40s.
.LONG TERM...(Friday through Wednesday)
Issued at 419 AM EST THU NOV 17 2016
Main focus in the medium range fcst period wl be on impact of deep
lo pres moving thru the wrn Great Lks on Fri. This lo pres wl result
in the first wdsprd snow of the season for Upr MI on Fri ngt/Sat as
colder air surges into the area on the heels of gusty nnw winds that
wl at least reach advy criteria near Lk Sup during this time.
Fri thru Sat...An intense, negatively tilted shrtwv over the Upper
MS River Valley on Fri mrng is fcst to lift newd acrs the Upper Lks
on Fri ngt, accompanied by a deep sfc lo that wl cross wrn Upr MI
Fri aftn/ngt. The vigorous dpva/deep lyr qvector dvgc/upr dvgc ahead
of this feature wl result in widespread pcpn over the nw cwa on the
cyc side of the h7 lo track and on the cold side of the warm fnt
stretching over that area to the ne of the aprchg sfc lo pres. Dry
slotting under the jet surge region over the rest of Upr MI wl limit
pcpn coverage. The pcpn over the nw wl be initially rain, but as the
vigorous dynamics cool the column sufficiently and the wshft to the
nnw in the wake of the passing sfc lo pres draw colder air into the
area late Fri/Fri ngt, the pcpn wl change primarily to snow. Another
shrtwv tracking toward the Lower Great Lks on Fri ngt wl sharpen the
upr trof over the wrn Great Lks, allowing a band of hier mid lvl rh
and rain changing to snow to track w-e acrs the area on Fri ngt.
Another impact of the shrtwv tracking to the s wl be to maintain a
sharper cyc nnw flow over the area thru much of Sat. As h85 temps
fall to under -10C on Sat in the resulting caa, the combination of
the sharp cyc flow and decreasing stability over Lk Sup, where water
temps are still arnd 8C, wl result in some lk enhancement,
especially where the strong nnw flow upslopes downwind of Lk Sup.
Right now, model fcsts sug up to 3-5 inches of snow wl accumulate in
the favored areas on Fri ngt thru Sat, when the arrival of some
dnva/larger scale qvector dvgc wl tend to limit the enhancement w-e.
Warming near Lk Sup wl tend to limit accums away fm the hier
terrain. Locations over the far scentral where this flow downslopes
wl pick up less than an inch. h925 winds incrsg up to 45-50 kts in
the presence of the strong caa/llvl destabilization wl also result
in very gusty winds as hi as 45 to perhaps 55 mph and some blowing
snow in the more exposed areas as well. The strong winds and the
longer fetch over the e half of Lk Sup wl cause waves to build at
least near 20ft, resulting in some lk shore flooding/beach erosion,
mainly over the Keweenaw and to the e of Marquette. At least advys
wl definitely be necessary at some point, with the hi winds being
the primary threat. At this point, opted to continue the SPS
issuance.
Sat ngt/Sun...As the upr trof axis shifts to the e, sharp dnva/deep
lyr qvector dvgc/subsidence that causes the invrn to subside toward
3-4k ft agl wl limit the sn shower intensity. But persistence of h85
temps as lo as -15C and h85-lk water temp contrast in excess of 20C
under llvl nnw flow wl cause lighter les to persist in the favored
sn belts. The aprch of trailing sfc hi pres/more acyc llvl flow/
warming h85 temps as the invrn lowers further wl tend to end the les
w-e on Sun.
Next week...As the trailing upr rdg builds over the wrn Great Lks, a
sfc hi pres/mid lvl dry air wl bring quiet, generally dry wx for
early in the week. The 00Z GFS does show another disturbance
tracking thru the Upper Lks and suppressing the upr rdg later on Mon
into Tue, but the GFS shows no pcpn in the absence of any sgnft mstr
inflow. H85 temps are fcst to moderate closer to 0C by Tue,
resulting in some modeation of the weekend chill. The longer range
guidance hints another shrtwv tracking near the Lower Great Lks may
cause more pcpn on Tue ngt thru Wed ngt before a trailing shrtwv rdg
brings a return of drier wx for Thanksgiving.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1154 PM EST WED NOV 16 2016
VFR conditions will prevail at KIWD/KCMX overnight. Meanwhile, at
KSAW, upslope winds off Lake Michigan should result in
stratus/fog/LIFR conditions developing late in the night. LLWS is
expected at all terminals overnight. Today, a trof developing into
the Upper Great Lakes from low pres organizing over the Plains will
result in cigs falling to MVFR during the aftn at KIWD/KCMX then to
LIFR in the evening. KSAW may improve to low MVFR for a time in the
aftn before falling to IFR.
&&
.MARINE...(For the 4 AM Lake Superior forecast issuance)
Issued at 453 AM EST THU NOV 17 2016
A strong storm system will move through Lake Superior late this
week. Prolonged gale event looks to set up. NE gales tonight into
Friday will give way to nrly gales from Friday night through Saturday
night. There could also be a few storm force gusts to 50 knots,
mainly late Friday night into Saturday morning over the cntrl and
east. The high winds will also quickly build waves into the 14 to 18
ft range early Saturday with waves gradually subsiding late Saturday
into Saturday night.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
Gale Warning from 4 AM Saturday to 7 AM EST Sunday for LSZ267.
Gale Warning from 1 AM Saturday to 7 AM EST Sunday for LSZ266.
Gale Warning from 1 AM EST /midnight CST/ Friday to 4 PM EST /3
PM CST/ Saturday for LSZ162.
Gale Warning from 1 AM EST /midnight CST/ Friday to 1 AM EST
/midnight CST/ Sunday for LSZ240>244-264.
Gale Warning from 1 AM Saturday to 1 AM EST Sunday for
LSZ245>251-265.
Gale Warning from 1 AM Friday to 7 PM EST Saturday for LSZ263.
Lake Michigan...
Gale Warning from 1 PM Friday to 1 AM EST Sunday for LMZ221-248-
250.
&&
$$
SHORT TERM...JLB
LONG TERM...KC
AVIATION...Rolfson
MARINE...JLB
For frequently asked questions about the Area Forecast Discussion
visit...
http://weather.gov/saltlakecity/general/afd_faqs.php
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
339 AM CST Thu Nov 17 2016
.SHORT TERM...(Today and tonight)
Issued at 328 AM CST Thu Nov 17 2016
Strong upper trough this morning was observed via water vapor
imagery lifting northeast over Utah. Pre frontal sfc trough is
currently stretched from central Kansas through southeast Nebraska.
Ahead of the trough in northeast Kansas, south winds remain strong
throughout the morning with speeds from 15 to 25 mph sustained,
gusting up to 40 mph at times. As the first area of low pressure
lifts northeast after 12Z, latest runs of the HRRR and Rap weaken
and shift winds to the west and north over north central Kansas.
This trend continues southeast across the CWA during the afternoon,
lending to some uncertainty into how long the winds maintain their
higher speeds. Overall trend for much of the CWA is to see the
highest winds mid morning through early afternoon, before gradually
waning from 15 to 20 mph sustained during the early evening. Have
maintained the Wind Advisory for east central areas, going until
00Z. A stout capping inversion at 850 mb during the day should
prevent any further mixing of warmer temps towards the surface.
Despite the high clouds increasing through the day, with the record
warm start this morning, highs should have no issue reaching the
upper 70s and perhaps a few lower 80s. For more information on fire
weather concerns, please see Fire Weather Discussion below.
For tonight, the upper trough is forecast to swing east northeast
across central Nebraska, while a secondary sfc low quickly deepens
over far northern Kansas. As they phase, we should see the pressure
gradient tighten once again over east central Kansas, increasing
south winds ahead of the front between 15 to 30 mph with gusts in
excess of 40 mph. Cold front timing slightly varies between
guidance, however sided closer to the GFS/ECMWF runs with it
entering north central areas by midnight and most of the cwa by
Friday morning. There is a slight chance for light rain showers over
far north central areas on the back side of the upper trough while
there is a secondary area of lift near the h85 front towards
Anderson and Franklin counties. Low temperatures continue to trend
above freezing from the upper 30s in north central KS to the middle
40s for eastern Kansas.
.LONG TERM...(Friday through Wednesday)
Issued at 328 AM CST Thu Nov 17 2016
Substantial cold advection will be ongoing through the day on Friday
with strong northwest winds gusting consistently in the 25 to 35 mph
range with a few stronger gusts possible. Expect a pretty extensive
stratocu cloud deck through the afternoon as well which will help
limit afternoon temperatures mainly in the 40s. Wind will weaken but
continue through Saturday morning, and despite wind and clouds
expect temps to fall into the 20s, with the coldest values in north
central KS where winds may be lighter closer to the surface high
pressure. The ridge of surface high pressure will then slide across
the area on Saturday with cool temperatures persisting but at least
with light winds.
Will see slightly warmer temperatures move back into the area as for
Sunday and Monday with another potent storm system moving across
Arizona by late Monday. A lead short wave and associated isentropic
lift and moisture will pose increasing chances for rain showers by
Tuesday morning with rain becoming likely through the day Tuesday as
the main upper low crosses the area. Model agreement among
deterministic and ensemble models is pretty good in timing and
location at this time, so felt comfortable maintaining rather high
end pops for a day 6 precip event. Temperatures are very likely to
be too warm to support snow and a cold rain will be favored across
the entire area. There will be a good shot of cold advection and
gusty northwest winds as the low pressure center passes through, but
it currently appears that precip will come to an end before profiles
cool enough to support any winter precip types.
The first glance at Wednesday and Thanksgiving points to a dry
forecast with seasonal temperatures although with indications of a
weak short wave trough crossing the region by late Thursday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1136 PM CST Wed Nov 16 2016
VFR conditions are expected throughout the period. LLWS will
continue through 14Z as the LLJ has increased to 50-60 knots near
2000 feet. Surface winds will remain gusty overnight with
sustained 10-15 knots and gusts 20-25 knots. Gusts will increase
to 25-35 knots after 14Z Thursday morning; continuing through the
period. Winds will begin to shift to the west and northwest at MHK
near the end of the period.
&&
.FIRE WEATHER...
Issued at 328 AM CST Thu Nov 17 2016
Very high fire danger conditions today as gusty southerly winds
continue at 20 to 30 mph sustained with gusts up to 40 mph through
early afternoon. Main uncertainty lies with dewpoints. Due to the
poor handling of dewpoints mixing heights from guidance yesterday,
trended towards the drier HRRR and RAP solutions for this type of
setup. Combined with the warm temps in the upper 70s to near 80
degrees, could only calculate minimum humidity values in the lower 30
percent range, which occurs during the late afternoon period. Winds
however weaken some by this time as a prefrontal sfc trough bisects
the area. Still should see winds in excess of 20 mph sustained for
eastern and far northeast Kansas during this time, however RH values
are forecast to not reach 20 percent. For this forecast, will
mention the very high fire danger wording, but do not plan on
issuing headlines.
Winds on Friday will be sustained in the 20-30 mph range with
occasional gusts to 35 mph or stronger out of the northwest.
Temperatures will be much cooler and this will keep RH values in
check with MinRH probably holding in the 35 to 43 percent range.
While this has been as strong storm system, it will result in
little to no precipitation for the local are so any fuels should
still be rather dry through Friday.
The next good chance for rain comes early Tuesday morning through
Tuesday night. This appears to be a pretty good chance for
widespread rain showers.
&&
.CLIMATE...
Issued at 310 PM CST Tue Nov 15 2016
Current Record High Temperatures
----------------------------------------------------------
November 17
Topeka 76
(year) (1999)
Concordia 76
(year) (1943)
Current Record Warm Low Temperatures
----------------------------------------------------------
November 17
Topeka 56
(year) (1941)
Concordia 57
(year) (2004)
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from 10 AM this morning to 6 PM CST this evening
for KSZ040-054>056-058-059.
&&
$$
SHORT TERM...Prieto
LONG TERM...Barjenbruch
AVIATION...Baerg
FIRE WEATHER...Barjenbruch/Prieto
CLIMATE...Prieto
Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
448 AM MST Thu Nov 17 2016
.AVIATION...
12Z TAF CYCLE
Strong winds will develop by mid to late morning as the jet stream
moves overhead. A Pacific cold front will cross from the west
shifting winds out of the northwest as the day progresses. Areas
of blowing dust will impact TAF sites on the eastern plains during
the afternoon with IFR conditions likely in dust-prone locations.
Scattered to isolated rain and mountain snow showers may also
develop across the northern mountains and northwest
highlands with some mountain obscuration possible, but these
should finish by sunset. Wind speeds will gradually weaken through
the evening.
44
&&
.PREV DISCUSSION...326 AM MST Thu Nov 17 2016...
.SYNOPSIS...
Strong to damaging winds are expected today. 70 mph gusts are not
out of the question for areas along and east of the central
mountain chain. This may cause damage to roofs, trees and
powerlines. Areas of blowing dust may also develop which will
reduce visibilities. Additionally, a strong cold front will plow
through the area dropping temperatures dramatically. Freezing
temperatures are expected for the majority of the area tonight,
and may be even colder Friday night across the plains. A warming
trend is expected this weekend, but another storm system is on tap
for Monday and Tuesday. However, this next system looks to bring
more precipitation than wind.
&&
.DISCUSSION...
Today is the day. Winds are going to be extraordinarily high today,
especially along and east of the central mountain chain late this
morning and this afternoon. Wind damage will be possible, given that
gusts could near 70 mph.
A trough of low pressure will cross northern NM and CO today with an
associated mid level jet of 50-65kt sweeping across NM during peak
heating. High clouds this morning should give way to sunny skies by
the afternoon, which will increase mixing heights over yesterday,
and tap into that stronger mid level flow. In addition, a Pacific
cold front will race across the state from west to east, and some
enhanced mixing right along the front may lead to some of the
strongest wind gusts of the day. Blowing dust remains a concern,
especially where soil moisture is lowest as well as downstream of
freshly plowed fields.
Only the ECMWF remains somewhat enthusiastic about some light precip
today. All other models, including the HRRR and RAP have
significantly backed off on QPF across the northwest mtns, not that
there was going to be much to begin with anyway. If any snow does
fall, it will undoubtedly be blown around, lowering visibilities.
The cold front will bring abruptly colder temperatures. Highs across
northwest NM will be 15 to 25 degrees colder than yesterday, and the
winds will make it feel even colder. Though winds will decrease
quickly this evening, there will remain some breezy areas overnight.
This will help temps from completing plummeting, but given the dry
air and strong cold air advection, this will be one of the coldest
night so far this season. The system will pull away on Friday, and
though sunny skies are expected, all areas will remain at or below
normal. Friday night/early Saturday morning may be colder than
Thursday night/early Friday across portions of the plains due to
less wind expected.
Ridging will move overhead on Saturday and temperatures will warm
accordingly. The ridge will shift eastward on Sunday, but
temperatures will continue to warm back above normal.
Models still showing a strong Pacific trough, which taps into some
subtropical moisture moving into SoCal on Monday, with precipitation
associated with this system impacting NM as early as Monday morning.
The system will shift quickly eastward, weakening somewhat as it
does so, but at least as the models stand now, precipitation should
spread over much of the CWA Monday through early Tuesday. PWATs
increase substantially during this period -- as much as 2-3 standard
deviations above normal. Record PWAT for 00Z Nov 22nd for ABQ is
0.64" and the GFS is suggesting we will easily exceed that. That
said, it will be a rather warm system and snow levels look to remain
at or above 8000 feet (and most of the precip will fall before snow
levels drop to 8kft).
Shortwave ridging will follow this system on Wednesday, but another
system may clip northern NM on Thursday.
34
&&
.FIRE WEATHER...
A couple of upper level storm systems will impact the fire weather
forecast area through early next week. The first, crossing today,
will bring very strong winds that will taper off gradually after
sunset. The second will bring more in the way of precipitation
mainly Monday and Monday night. By the end of the week all parts of
the forecast area should experience a hard freeze.
A sharp upper level trough will pass north of NM today steering the
polar jet stream overhead. A 991 mb surface low in SE CO will help
winds blow the strongest across northeast areas and the central
mountains/highlands, though most locations east of the continental
divide can expect strong winds. Clouds overhead this morning will
shift eastward by mid day, helping to mix stronger winds aloft
downward. Sustained winds should approach 50 mph across higher
peaks of the Sangre de Cristos and around Las Vegas, the epicenter
of strongest wind speeds. Gusts there should reach near 70 mph.
Gusts to 60 mph are a good bet across the remainder of NE and E
central areas, and to 50 mph farther west to the continental divide.
A Pacific Cold front will also cross from the west shifting winds
out of the northwest by late in the day.
In addition, humidities will fall below 15% across much of the east
and the southern tier of zones this afternoon. We will continue the
Red Flag warning we have in effect for these areas. Haines indices
don`t look too bad for this event, with readings in the 3 to 5
range.
A ridge of high pressure aloft will cross from the west Friday and
Saturday allowing temperatures to rebound Saturday after a cooler
day Friday. A lee trough will cause breezy conditions to return to
east central and northeast areas Saturday as temperatures warm.
An upper level low pressure system is forecast to weaken into a
trough as it tracks east northeastward across northern NM from S CA
Monday and Monday night. Showers may begin moving into western
areas as early as Sunday night. The best shot of wetting precip
will be along and west of the central mountain chain Monday and
Monday night, then spottier wetting precip will be possible across
north central and northwest areas into Tuesday as the system exits
northeastward. The snow level will remain above 10,000 feet for most
of the event. It may lower to near 8,000 feet late Monday night into
Tuesday morning...after the better fetch of moisture exits. The
northern mountains look favored for snow accumulation. Southwest
winds will become gusty many places on Monday. Gusts should
strengthen farther out of the northwest Tuesday behind another
Pacific cold front that will cross from the west Monday night.
Temperatures won`t fall as much with the early week system, but
highs should dip below normal mainly across central and western
areas on Tuesday.
Another ridge of high pressure will cross Wednesday.
44
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from noon today to 7 PM MST this evening for the
following zones... NMZ103-104-106>109.
Wind Advisory until 8 PM MST this evening for the following zones...
NMZ503-504-506>508-510-511-516>520-525-535>538.
High Wind Warning until 8 PM MST this evening for the following
zones... NMZ512>515-521>524-526>534-539-540.
&&
$$
Area Forecast Discussion
National Weather Service Dodge City KS
534 AM CST Thu Nov 17 2016
...Updated aviation discussion...
.SYNOPSIS...
Issued at 248 AM CST Thu Nov 17 2016
A strong upper level storm system will approach the high plains
today and then eject into the upper midwest by Friday. A cold
front will slip southward through Garden City and Dodge City to
the Oklahoma state line this morning system since the upper level
system is still digging east-southeastward. This front will move
back to the north as a warm front this afternoon as the upper
level trough becomes negatively tilted and approaches the high
plains. A north to south oriented front cold front will push
eastward into western Kansas toward evening. How far north the
warm front gets through 5 pm will determine fire weather
conditions and strength/direction of low level winds. After this
system passes this evening, colder air will surge into western
Kansas with the coldest air of the season. Upper level ridging and
lee troughing will commence over the western high plains by
Saturday and persisting through Sunday and early Monday. The next
upper level trough will approach the high plains by Monday night
and Tuesday.
&&
.SHORT TERM...(Today and tonight)
Issued at 248 AM CST Thu Nov 17 2016
Temperatures will be tricky today given the early morning cold frontal
passage and late afternoon warm frontal surge. The warm surge may
occur after peak heating so that locations such as Jetmore and
Garden City may not get into the warm and dry sector. There may be
a sharp gradient in temperatures this afternoon from upper 50s to
near 60 at Wakeeney to near 80 at Englewood and Liberal. Winds may
approach high wind warning criteria from Elkhart to Liberal this
afternoon since RAP soundings indicate deep mixing up through
700mb with 50 kt winds at that level. Much cooler air can be
expected by late tonight.
.LONG TERM...(Friday through Wednesday)
Issued at 248 AM CST Thu Nov 17 2016
A slow warming trend can be expected Saturday through Monday ahead
of the aforementioned upper level trough. There are small chances
for rain showers Monday night into Tuesday as low level moisture
increases ahead of the system; and a short-lived cool down is
expected by Tuesday in the wake of the system.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 534 AM CST Thu Nov 17 2016
A frontal boundary moving into central and southwest Kansas will
become stationary and then lift back northward somewhat this
afternoon. Winds will be variable at 10 knots or less at the
terminals through today. South of the front, gusty southwest winds
are expected to develop and these stronger winds could approach
the Garden City and Dodge City terminals late this afternoon. The
front will accelerate southeastward tonight with gusty northwest
winds behind it. MVFR cigs could develop around Hays for several
hours this evening.
&&
.FIRE WEATHER...
Issued at 707 PM CST Wed Nov 16 2016
The only county to be removed from the red flag warning is
Hodgeman since the warm front is not expected to progress that far
north this afternoon. Finney and Ford counties may also be too far
north for critical fire weather conditions to be met for 3 hours.
High winds and very low humidity will lead to the most favorable
conditions for wildfires from Stanton and Morton counties eastward
to Seward county.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 72 34 48 22 / 0 10 0 0
GCK 69 33 46 19 / 10 20 0 0
EHA 72 30 47 21 / 0 10 0 0
LBL 78 32 50 20 / 0 0 0 0
HYS 63 36 46 22 / 10 20 0 0
P28 77 41 52 26 / 0 10 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 11 AM CST /10 AM MST/ this morning to 7 PM
CST /6 PM MST/ this evening for KSZ061>063-074>078-084>088.
&&
$$
SYNOPSIS...Finch
SHORT TERM...Finch
LONG TERM...Finch
AVIATION...Gerard
FIRE WEATHER...Finch
Area Forecast Discussion
National Weather Service Grand Forks ND
947 AM CST Thu Nov 17 2016
.UPDATE...
Issued at 947 AM CST Thu Nov 17 2016
Dry low level airmass preventing radar returns from reaching the
ground...and removed rain through the morning hours. Otherwise the
forecast is on track for the remainder of today.
Incoming 12z model guidance coming in line with previous
guidance...showing the track of the winter storm slightly south
and east of what the mean track was yesterday. Thus...confidence
is increasing in the track of this upcoming system. Will attempt
to make a headline decision early afternoon.
&&
.SHORT TERM...(Today and tonight)
Issued at 254 AM CST Thu Nov 17 2016
What happens at the start of the watch period late tonight will
be the main headache for the short term.
The upper trough currently digging into the Desert Southwest will
move into CO/KS by the end of the day. The surface trough
currently extending from KS up into southern MN will deepen, with
cold air advection on the northwest side of it. By this evening,
all but the far southeastern counties will see 925mb temps below
zero C. Lowered highs just a bit across the west where cold air
advection will make it difficult to get out of the 30s, with 40s
in the east. Models start mid level frontogenesis over our
southern counties by this afternoon, and several put out some
light QPF although the HRRR and RAP keep anything from reaching
the ground until later this evening. Will continue the trend of
slowly ramping up POPs this afternoon. Mostly rain, although some
snow mixing in is possible across the western edge towards sunset.
Tonight, the upper trough begins lifting towards the upper
midwest, with the surface low closing off and reaching the IA/MN
border by 12Z. The first frontogenesis band starts to diminish
late tonight, but even stronger frontogenesis gets going a bit
further east and is well correlated with strong Q vector
convergence. There continues to be minor variations in the exact
track of the system which have big impacts on how much snow falls
across our southern and eastern counties. With high levels of
uncertainty will hold off on any upgrades to headlines and keep
things as a watch for now.
.LONG TERM...(Friday through Wednesday)
Issued at 254 AM CST Thu Nov 17 2016
Friday...The upper trough will lift into northeastern MN, with the
strong surface low tracking into the Great Lakes and putting MN
in the cross hairs for the deformation zone snow band. With some
frontogenesis there is also banding potential and it is difficult
at this point to tell where that will exactly end up. SREF plumes
for Fargo have snow totals by the end of the day Friday ranging
from just over half an inch to around 20 inches. Several of the
most recent model runs have been trending further east with the
main precipitation band, but there are still ensemble members
dropping quite a bit of QPF over southeastern ND into northwestern
MN. With high uncertainty still will keep headlines in the watch
phase. What is more certain is wind. With the track of the surface
low the tight gradient will be right over our southern counties.
925mb winds will be pushing 50 kts and 850mb winds will be even
higher. Bumped up winds above the blended solution and have gusts
in the far southeast above 45 kts at times Friday. Temps across
the southeastern counties will see a midnight high with readings
steady or slowly falling into the low 30s.
Saturday to Wednesday night...
Overall dry period with minimal weather impacts and much cooler than
the first half of the month with highs generally in the 30s and lows
in the teens and 20s. The exception will be if and where deep snow
pack develops with Friday storm system. Temps above the snowpack
will have a hard time warming and will cool more readily at night
than snow free areas. Sunday will be the first morning with little
mixing and few clouds so expecting temps over the snow pack to drop
into the low teens if not further. The rest of the week will see a
slow moderation and a shot at 40 degrees by Thanksgiving day.
500MB NW flow with SFC high pressure across the northern plains will
gradually give way in the progressive flow aloft to the next short
wave moving across the central plains on Monday night into Tuesday.
Will keep PoPs limited to the far eastern portions of the FA for
Tuesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 635 AM CST Thu Nov 17 2016
Some MVFR level clouds have moved into the area and brought
ceilings down to the 1500-3000 ft range with some lower IFR
conditions at KBJI. Think there should be some recovery later
today to high MVFR/low VFR. Winds will be increasing with gusts
over 25 kts this afternoon. MVFR and lower ceilings will return
later tonight as a storm system approaches. At this point, KFAR
and KBJI have the best chances of precipitation. Kept -RASN
changing over to all -SN mention at those two sites. Some lowered
visibilities are possible at the end of the period with SN and
BLSN especially at KFAR, but will keep above 2SM for now and add
some lower mentions later. North winds will pick up tomorrow
morning with some gusts above 30 kts possible.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Winter Storm Watch from late tonight through Friday afternoon
for NDZ039-049.
Blizzard Watch from late tonight through Friday afternoon for
NDZ052-053.
MN...Winter Storm Watch from late tonight through Friday afternoon
for MNZ002-003-006-009-015>017-022>024-027-028-032.
Blizzard Watch from late tonight through Friday afternoon for
MNZ029>031-040.
&&
$$
UPDATE...TG
SHORT TERM...JR
LONG TERM...JR/JK
AVIATION...JR
Area Forecast Discussion
National Weather Service Grand Junction CO
402 AM MST Thu Nov 17 2016
.SHORT TERM...(Today through Friday)
Issued at 401 AM MST Thu Nov 17 2016
Strong cold front stretching from Lake Powell northeast to Craig
will continue to move slowly eastward this morning. Temperatures
dropping quickly into the 30s behind the front with light showers
developing. HRRR running about 2 hours behind current position
with RAP having a better handle on the now period. As such, will
use the RAP in regards to timing the arrival of the colder air
across the forecast area. Most high temperatures were hit around
midnight last night and we will likely have a day of steady or
falling temperatures as the front moves through. The front should
be clearing all of eastern Utah between 6 and 7 am this morning
then through the Grand Valley by 9 am, exiting western Colorado
by noon.
Radar activity slowly increasing with a few showers breaking out.
Trend will be for an increase in showers as we see upper level
support arrive by midday. Cooling aloft combined with rapid sfc
cooling will allow rain showers to flip over to snow showers with
the northern and central zones favored for the heavier QPF values.
Have backed off the higher end of the snowfall accumulation for
our mountains by an inch or two, but still expect significant
travel impacts in our CWA. So no changes to current weather
highlights. Even an inch or two of snow will cause early season
issues for drivers that are caught off guard after the recent
warm weather.
Snow showers linger across the northern and central mountains
through most of tonight in favorable northwesterly orographic
flow, before ending early Friday morning.
Coldest night of the season anticipated tonight for just about
the entire forecast area and freeze warnings already issued for
the few valleys that managed to escape the freezing weather so
far this fall. That will come to an end tonight and again Friday
night with temps down into the teens and 20s with some single
digit readings anticipated for the higher valleys.
.LONG TERM...(Friday through Wednesday)
Issued at 401 AM MST Thu Nov 17 2016
As the storm system exits the region to the east, northwest flow
will gradually weaken on Friday bringing an end to upslope
precipitation in the northern mountains by noon. Cold temperatures
are expected overnight Friday into Saturday as skies clear and
winds diminish with fresh snowfall over much of the higher
terrain. 500mb heights will slowly rise on Saturday as a ridge of
high pressure builds in from the Southwest. Expect high
temperatures near normal values on Saturday with mostly sunny
skies. Temperatures will continue to warm with dry weather on
Sunday as flow turns southwesterly ahead of the next storm system.
Clouds associated with the next system should arrive into the
Four Corners region late Sunday into Monday with precipitation
arriving as early as Monday morning. Some differences in modeL
timing between the GFS and ECMWF exist at this time, however much
of the region will likely see another round of snow on Monday and
Tuesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 401 AM MST Thu Nov 17 2016
Shifting winds gusting to 40 kts expected today as we see
southwest winds swing to the west and northwest behind a strong
cold front moving through. CIGS will be dropping at all sites this
morning with widespread mvfr conds anticipated between 17z today
and 09z tonight. Areas of rain and snow will also be developing
and increasing in coverage through today with snow showers
lingering over the northern and central mountains tonight. Expect
mountain obscuration to be widespread with freezing levels
dropping to the valleys floors by this evening.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...Winter Weather Advisory until midnight MST tonight for COZ003-
014-017>019.
Freeze Warning from 6 PM this evening to 10 AM MST Friday for
COZ006.
Winter Storm Warning until midnight MST tonight for COZ001-002-
004-009-010-012-013.
Winter Weather Advisory from 8 AM this morning to midnight MST
tonight for COZ005.
UT...Winter Weather Advisory until midnight MST tonight for UTZ025.
Freeze Warning from 6 PM this evening to 10 AM MST Friday for
UTZ022-027.
Winter Weather Advisory until 6 PM MST this evening for UTZ023.
Winter Weather Advisory until 6 PM MST this evening for UTZ028.
&&
$$
SHORT TERM...JDC
LONG TERM...JAM/MAC/JDC
AVIATION...JDC
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
513 AM CST Thu Nov 17 2016
.SHORT TERM...
321 AM CST
Through Tonight...
Today we ascend what will be a 48-hour roller coaster temperature
ride with near-record warmth this afternoon. Regarding impacting
weather, wind gusts will be on their way up today, though still
be a fair amount short of advisory criteria.
Low pressure around 997 mb will basically remain in place today
near the NE/IA border with its warm front lifting over the area
late this morning. Impressive 925mb warmth of 22C was observed at
KSGF last evening reflective of the warm maximum that will
translate northeastward with the front. The 925mb temperatures
should peak at 18-20C over the CWA using a nudge up above a
guidance blend, and that is basically record territory for mid-
November. Chicago ORD averages a high of 71 when 925mb
temperatures reach that high in November using the NARR (North
American Regional Reanalysis). The only concern from not reaching
into these 70s would be the cirrus. The RAP 300mb humidity
forecast has a good handle on present cirrus and its evolution
matches upstream water vapor imagery, indicating a thin but at
times broken cirrus over much of the CWA today. Advection will
play a greater role than solar warming, but still the cirrus
could rob a couple degrees from forecast highs in the north. See
Climate discussion below for more on records.
Wind gusts will increase to 25-30 mph, maybe a tad higher, behind
the warm front as projected by modified NAM/GFS soundings. These
gusts will likely just continue through the entire night, likely
just a little less frequent. This will ensure a very mild night,
with lows 5-8 degrees above normal high temperatures this time of
year.
MTF
&&
.LONG TERM...
321 AM CST
Friday through Wednesday...
We will remain at the peak of the temperature roller coaster
Friday morning before a sharp descent that will continue into
Saturday with little temperature recovery this weekend. The main
weather message along with this first cold punch of the season is
the winds, which at times later Friday through the day Saturday
very well could gust to 40+ mph. A Wind Advisory may be needed by
the next shift.
The key features and mass fields of this classic late autumn
system have wobbled very little in guidance the past 24-hours
with just some slight slowing of the envelope of solutions. The
low should be around 996 mb over western Wisconsin by midday
Friday, favoring a pronounced warm sector over the CWA through
early afternoon. Have nudged up highs in eastern areas toward 70
given strong warm advection and such a warm starting point to the
day. The stout cold front is presently forecast to pass west-to-
east through the CWA in the 12-5 p.m. period. Have used raw
guidance for the hourly temperatures to note what should be a
constant but notable drop from fropa through the evening.
Wind gusts look to be at their peak in the several hours
immediately behind the cold front, where unidirectional southwest
flow aligns with strong cold advection and a high isallobaric
component. Top of the channel winds are 45-50 mph on the NAM and
GFS, especially in the northern half of the CWA. Gusts will remain
30+ mph and possibly 40+ mph at times through the night.
Besides these gusts being realized in the window of time after
fropa, any showers or thunderstorms ahead of the front during the
afternoon could also tap these high top of the channel synoptic
winds. Showers and convection are most favored along/east of I-55
as the mid-level jet and associated lift wrap around the upper
trough and overlay the front and the narrow moist tongue. Again
the severe threat is low, but with these type of fronts there can
be isolated near-severe gusts even without lightning being
present.
Model differences for wraparound flurries or light snow shower
potential overnight Friday and Saturday morning does vary, but do
see a decent potential to rattle out at least scattered, wind-
blown, light precip...especially over the northern CWA. Using the
Bourgouin precipitation-type technique, mainly the low- level
positive energy with respect to wet bulb, the profiles are cool
enough for snowflakes in north central Illinois already by early
overnight Friday and in Chicago by daybreak Saturday. Not
expecting any accumulation with any of this, but if some true snow
showers materialize it is possible to get some sharply reduced
visibility due to the wind combination.
Wind gusts will gradually ease Saturday afternoon as the low pulls
away and more so later Saturday night. Temperatures during the day
will struggle to rebound much if at all past the upper 30s, with
lows in the lower to mid 20s for many locations. Gradually veering
lake effect flow will likely support showers into northeast
Porter County in Indiana Saturday night into Sunday morning. The
depths of the clouds will be shrinking due to drying aloft, so
not expecting anything big, but if indeed the showers do occur,
some of that likely will be snow.
High pressure will prevail Sunday-Monday, with a chilly night in-
between due to the light winds and forecast clear sky. Some of the
first teens of the year are likely in favored outlying locations.
Looking ahead toward the holiday week, the next system is showing
decent predictability in global guidance in terms of timing and
the Midwest being impacted with precipitation Tuesday-Wednesday.
The past 24-hours have shown a slight northwest trend with this,
but that`s well in the envelope of uncertainty still, so made
little changes in the blended solution. Have rain showers likely
through a good portion of Tuesday into Wednesday. Right now this
system is progressive enough not to drag in too cold of air while
forcing for precip is present. However, there still could be some
travel impacts with wind-whipped rain and low clouds on
Wednesday, and obviously more so if the systems shifts a tad
further south (meaning cooler temperatures).
MTF
&&
.CLIMATE...
321 AM CST
Temperatures are forecast today to be within a few degrees of
record highs, and cannot rule out reaching them.
Record Highs for Thursday, November 17:
Chicago: 74 (1975)
Rockford: 73 (1941)
The normal last 70 degree day at Chicago is October 30, and there
have been just five years in the past 40 with a 70 degree day
after the midpoint of November. The normal last 70 degree day at
Rockford is October 27, and there has only been one year (1999) in
the past 40 with a 70 degree day after the midpoint of November.
The latest 70 degree day at Rockford on record is November 21,
1913.
MTF
&&
.AVIATION...
For the 12Z TAFs...
The main aviation weather concerns today will be the increasingly
gusty southerly winds today. Low-level wind shear will also be a
concern, especially early this morning and again tonight as the
winds a couple thousand feet off the surface increase up around 45
KT. These strengthening winds are all thanks to a developing area
of low pressure over the Central Plains. This storm system is
expected to shift northeastward across the Upper Midwest as a
potent storm system on Friday. As it does so, expect southerly
winds to remain elevated through the period, with gusts up around
25-28 KT at times.
This system will drive a strong cold front across the area by
late Friday afternoon/evening. Strong westerly winds are expected
in its wake. However, a period of showers, and perhaps a
thunderstorm, are also possible as the front approaches the area
later Friday. This is currently beyond the current 30 hour TAF
period, so no mention of rain or a wind shift has been included in
the latest TAF.
KJB
&&
.MARINE...
221 AM CST
The main forecast concerns during the period continue to focus on
a strong storm system expected to have a major impact on the
Great Lakes Friday through Sunday.
A significant Autumn season storm system is will impact the Upper
Midwest and Great Lakes region through Sunday. Initially, the
winds should be increasing out of the south over the lake
today as the storm system take shape across the Central Plains.
However, on Friday as the storm system strengthens over the Upper
Mississippi Valley, south to southwesterly winds will likely
increase to 35 KT Gales during the day. The low pressure area is
then forecast to shift northeastward over the Upper Lakes region
into Saturday morning. As it does so, a strong cold front will
sweep eastward over the lake sometime late Friday or Friday
evening. Winds will then likely become westerly and increase more
into the high end gale category up to 45 KT by Saturday as much
colder air spills over the lake on the back side of the low. Given
the strength of this storm system, there could also be a period of
near 50 KT Storm force winds on Saturday over northern Lake
Michigan as strong pressure rises overspreads the lake on the
back side of the low. Gale force winds could continue into early
Sunday before abating.
Given the high impact/high confidence forecast of gales on the
lake, we have opted to go ahead and issue the gale warning for the
entire lake, including the IL and IN near shore waters, from
midday Friday through Sunday morning. The strongest winds are
likely Friday night into Saturday. There is also the possibility
that an upgrade to a storm warning may be needed for northern Lake
Michigan for Saturday. However, at this time, we felt it prudent
to get the warning out as at the very least it will be a high end
Gale event.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...Small Craft Advisory...NEARSHORE WATERS
UNTIL NOON Friday.
Gale Warning...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...NOON
Friday TO MIDNIGHT Sunday.
Gale Warning...LMZ777-LMZ779...NOON Friday TO 9 AM Sunday.
&&
$$
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Area Forecast Discussion
National Weather Service Marquette MI
647 AM EST Thu Nov 17 2016
.SHORT TERM...(Today and tonight)
Issued at 453 AM EST THU NOV 17 2016
WV imagery and RAP analysis indicated a mid/upper level trough over
the wrn CONUS with a vigorous shortwave moving into sw Utah and a
ridge from the lower MS valley to the cntrl Great Lakes. At the
surface, southerly flow was increasing between a trough from n cntrl
KS to ne MN and high pressure over the ern Great Lakes. IR loop
showed increasing mid/high clouds with the WAA pattern over the
region. The sse flow has also brought increasing low level
moisture/clouds, aided by Lake Michigan, into cntrl Upper Michigan.
Today, despite thickening cloud cover, WAA will be strong enough to
boost temps from early morning readings in the mid 50s to max temps
in the lower to mid 50s.
Tonight, pcpn increasing with 300k-305k isentropic lift along the
strengthening 850-700 mb front from wrn Lake Superior into ne MN is
expected to gradually sag into the wrn cwa. Rain will become likely
over the far west from IWD to CMX with chance pops over the rest of
the nw half of the cwa. Otherwise, temps will remain well above
normal with lows into the 40s.
.LONG TERM...(Friday through Wednesday)
Issued at 419 AM EST THU NOV 17 2016
Main focus in the medium range fcst period wl be on impact of deep
lo pres moving thru the wrn Great Lks on Fri. This lo pres wl result
in the first wdsprd snow of the season for Upr MI on Fri ngt/Sat as
colder air surges into the area on the heels of gusty nnw winds that
wl at least reach advy criteria near Lk Sup during this time.
Fri thru Sat...An intense, negatively tilted shrtwv over the Upper
MS River Valley on Fri mrng is fcst to lift newd acrs the Upper Lks
on Fri ngt, accompanied by a deep sfc lo that wl cross wrn Upr MI
Fri aftn/ngt. The vigorous dpva/deep lyr qvector dvgc/upr dvgc ahead
of this feature wl result in widespread pcpn over the nw cwa on the
cyc side of the h7 lo track and on the cold side of the warm fnt
stretching over that area to the ne of the aprchg sfc lo pres. Dry
slotting under the jet surge region over the rest of Upr MI wl limit
pcpn coverage. The pcpn over the nw wl be initially rain, but as the
vigorous dynamics cool the column sufficiently and the wshft to the
nnw in the wake of the passing sfc lo pres draw colder air into the
area late Fri/Fri ngt, the pcpn wl change primarily to snow. Another
shrtwv tracking toward the Lower Great Lks on Fri ngt wl sharpen the
upr trof over the wrn Great Lks, allowing a band of hier mid lvl rh
and rain changing to snow to track w-e acrs the area on Fri ngt.
Another impact of the shrtwv tracking to the s wl be to maintain a
sharper cyc nnw flow over the area thru much of Sat. As h85 temps
fall to under -10C on Sat in the resulting caa, the combination of
the sharp cyc flow and decreasing stability over Lk Sup, where water
temps are still arnd 8C, wl result in some lk enhancement,
especially where the strong nnw flow upslopes downwind of Lk Sup.
Right now, model fcsts sug up to 3-5 inches of snow wl accumulate in
the favored areas on Fri ngt thru Sat, when the arrival of some
dnva/larger scale qvector dvgc wl tend to limit the enhancement w-e.
Warming near Lk Sup wl tend to limit accums away fm the hier
terrain. Locations over the far scentral where this flow downslopes
wl pick up less than an inch. h925 winds incrsg up to 45-50 kts in
the presence of the strong caa/llvl destabilization wl also result
in very gusty winds as hi as 45 to perhaps 55 mph and some blowing
snow in the more exposed areas as well. The strong winds and the
longer fetch over the e half of Lk Sup wl cause waves to build at
least near 20ft, resulting in some lk shore flooding/beach erosion,
mainly over the Keweenaw and to the e of Marquette. At least advys
wl definitely be necessary at some point, with the hi winds being
the primary threat. At this point, opted to continue the SPS
issuance.
Sat ngt/Sun...As the upr trof axis shifts to the e, sharp dnva/deep
lyr qvector dvgc/subsidence that causes the invrn to subside toward
3-4k ft agl wl limit the sn shower intensity. But persistence of h85
temps as lo as -15C and h85-lk water temp contrast in excess of 20C
under llvl nnw flow wl cause lighter les to persist in the favored
sn belts. The aprch of trailing sfc hi pres/more acyc llvl flow/
warming h85 temps as the invrn lowers further wl tend to end the les
w-e on Sun.
Next week...As the trailing upr rdg builds over the wrn Great Lks, a
sfc hi pres/mid lvl dry air wl bring quiet, generally dry wx for
early in the week. The 00Z GFS does show another disturbance
tracking thru the Upper Lks and suppressing the upr rdg later on Mon
into Tue, but the GFS shows no pcpn in the absence of any sgnft mstr
inflow. H85 temps are fcst to moderate closer to 0C by Tue,
resulting in some modeation of the weekend chill. The longer range
guidance hints another shrtwv tracking near the Lower Great Lks may
cause more pcpn on Tue ngt thru Wed ngt before a trailing shrtwv rdg
brings a return of drier wx for Thanksgiving.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 646 AM EST THU NOV 17 2016
At KSAW, upslope winds off Lake Michigan have resulted in result in
stratus/fog/IFR conditions. LLWS is also expected early in the TAF
period at KSAW. A trough developing into the Upper Great Lakes from
low pres organizing over the Plains will result in cigs falling to
MVFR during the aftn at KIWD/KCMX then to LIFR in the evening. KSAW
may improve to low MVFR for a time in the aftn before falling to IFR.
&&
.MARINE...(For the 4 AM Lake Superior forecast issuance)
Issued at 453 AM EST THU NOV 17 2016
A strong storm system will move through Lake Superior late this
week. Prolonged gale event looks to set up. NE gales tonight into
Friday will give way to nrly gales from Friday night through Saturday
night. There could also be a few storm force gusts to 50 knots,
mainly late Friday night into Saturday morning over the cntrl and
east. The high winds will also quickly build waves into the 14 to 18
ft range early Saturday with waves gradually subsiding late Saturday
into Saturday night.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
Gale Warning from 4 AM Saturday to 7 AM EST Sunday for LSZ267.
Gale Warning from 1 AM Saturday to 7 AM EST Sunday for LSZ266.
Gale Warning from 1 AM EST /midnight CST/ Friday to 4 PM EST /3
PM CST/ Saturday for LSZ162.
Gale Warning from 1 AM EST /midnight CST/ Friday to 1 AM EST
/midnight CST/ Sunday for LSZ240>244-264.
Gale Warning from 1 AM Saturday to 1 AM EST Sunday for
LSZ245>251-265.
Gale Warning from 1 AM Friday to 7 PM EST Saturday for LSZ263.
Lake Michigan...
Gale Warning from 1 PM Friday to 1 AM EST Sunday for LMZ221-248-
250.
&&
$$
SHORT TERM...JLB
LONG TERM...KC
AVIATION...JLB
MARINE...JLB
Area Forecast Discussion
National Weather Service Pueblo CO
513 AM MST Thu Nov 17 2016
.SHORT TERM...(Today and tonight)
Issued at 513 AM MST Thu Nov 17 2016
...High winds and Extreme Fire Weather Conditions expected across
the southeast plains along/south of Highway 50 today...
...Snow for the Central Mountains and Palmer Divide through this
Evening...
Potent upper trof across the Great Basin early this morning will
continue to translate eastward across Colorado today. Have seen some
snow showers in area radars along the west slopes overnight...and
snow should continue to increase through the morning as upper lift
increases ahead of the trof. Still getting around 3 to 8 inches of
snow for the western mountains with the heaviest falling across the
higher elevations of the Sawatch and Mosquito ranges. Have hoisted
a winter weather advisory for this area as winds will likely cause
some blowing snow and poor visibilities at times during the
afternoon. Farther south...dry air wrapping around the base of the
trof should serve to decrease snow for the southwest mountains
during the afternoon...so don`t think impacts will be as high down
that way where snow totals are more in the 1 to 4 inch range.
For the plains...initial push of the front is starting to move into
southeast CO with winds increasing out of the northeast at 10-15
mph. Across the mountain areas have seen gusts up in the 50-60 mph
range at times...particularly across the Wets and Sangre De Cristo
range...and radar is showing a high wind signature at times. As
upper jet translates in later this morning...models mix down strong
southwest winds as the sfc low deepens across southeast CO and front
recedes back to the north. HRRR has been persistent in showing
fairly widespread gusts in the 50-60 mph range across southern
portions of the southeast plains...mainly to the south of highway 50
during the afternoon. Sfc pressure gradient looks pretty impressive
so think high winds are a good enough bet to hoist a high wind
warning for the southern tier counties of the plains. Its possible
that these warnings may need to be extended another row of counties
northward depending on how things evolve...but will continue to
monitor latest HRRR runs before deciding. Areas of blowing dust and
strong cross winds along north south oriented roadways will result
in hazardous travel conditions through late afternoon and early
evening. Other area where high res models indicate potential for
high winds is across the Sangre De Cristo mountains and Wet
mountains. Model cross sections and soundings do not show
conditions conducive to mountain wave development...and think that
wind gusts are more likely to stay below the 75 mph threshold.
Meanwhile...northerly push of colder air will spread southward down
the Palmer Divide between 20-21z...with quickly falling temperatures
and snow spreading into the Pikes Peak region. Models suggest peak
snowfall will occur right around the evening commute but with the
residual warmth in the ground...think roadways will stay slushy at
first. Local models still indicate around 1 to maybe 2 inches of
snow across Teller/northern El Paso county through this
evening...with snow quickly winding down during the late evening and
overnight. Untreated roads may become slick during the evening as
temperatures fall into the lower 20s and teens by midnight. Given
strong north winds in the 20-40 mph range...could see some reduced
visibilities in blowing snow during the evening commute as well.
Isolated showers will spread south of the Palmer Divide during the
evening...but most will stay north of highway 50. Given strong
downslope off the Palmer...and strong downward forcing behind the
trof...little to no precipitation is expected across the plains.
Winds will shift out of the north during the evening...then
gradually subside by early Friday morning as the system pulls away.
-KT
.LONG TERM...(Friday through Wednesday)
Issued at 513 AM MST Thu Nov 17 2016
Primary meteorological concerns during the longer term include
temperatures, gusty winds at times and increased precipitation
potential from Monday into Tuesday evening.
Recent forecast model soundings, computer simulations and PV
analysis for the longer term indicate that generally dry
conditions should be noted from Friday into Sunday night as
upper ridging transitions from Arizona into Texas during this
time-frame.
Then unsettled meteorological conditions are anticipated from
Monday into Tuesday night as upper disturbance located near
southern California on Monday moves across New Mexico and Colorado
into Tuesday before moving east of the forecast district by next
Wednesday. In addition, next northerly surge is projected to move
across eastern sections of the CWA by next Tuesday.
For sensible weather, basically dry conditions in combination with
below seasonal temperatures will be depicted from Friday into
Saturday morning(where minimal temperatures in the teens will be
commonplace Saturday morning across large sections of the forecast
district). Warming temperatures in combination with continued dry
conditions should then be noted from later Saturday into Sunday
night.
Then, as system impacts the region, expect that increasing
pops(including higher terrain snow) will be noted over western
portions of the forecast district Monday, with precipitation
shield(as well as higher terrain snow) then spreading east into
many locations from later Monday into Tuesday evening with
improving meteorological conditions expected to return by next
Wednesday as system pulls away from Colorado.
As mentioned earlier, coolest temperatures during the longer term
should be noted from Friday into Saturday morning, while warmest
conditions are anticipated Sunday. Finally, highest potential of
gusty winds are expected Friday and then again by early next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 513 AM MST Thu Nov 17 2016
Deteriorating CIGS and VIS expected along the Contdvd this morning
with conditions dropping to the IFR to LIFR category in SN/BLSN. TAF
sites however will stay VFR with winds increasing from the southwest
at KALS during the late morning. Initially winds at KCOS and KPUB
will swing around from the Northeast then east and southeast as a
front moves through. However...winds will switch around from the
south then southwest by 18z with gusts up to 40 kts. Winds will
shift around from the west with gusts up to 45 kts during the mid-
late afternoon. This will cause reduced visibilities in BLDU at KALS
and KPUB. A cold front will drop south of the Palmer Divide around
20-21z...bringing a wind shift out of the north for KCOS around 22z
and KPUB between 00-01z. VCSH will be possible along/behind the
front at KCOS...with rain changing to snow by 00z. KCOS terminal
should see less than 0.5 snowfall before snow decreases during the
evening. KPUB will stay dry. Conditions will gradually improve
after 06z as the system exits the region and SHSN comes to an end
over the mountains. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
High Wind Warning from 10 AM this morning to 6 PM MST this
evening for COZ087-088-094-099.
Red Flag Warning from 10 AM this morning to 6 PM MST this
evening for COZ228>230-232-233-235>237.
Winter Weather Advisory until midnight MST tonight for COZ058-
060.
&&
$$
Area Forecast Discussion
National Weather Service North Platte NE
340 PM CST Thu Nov 17 2016
.SYNOPSIS...
Issued at 340 PM CST Thu Nov 17 2016
A vigorous H5 trough of low pressure continues to track across
southern Colorado this afternoon. Instability in association with
this system has increased this afternoon along the front range of
Colorado as abundant convective cloudiness has developed. This
instability has spread north into the Nebraska panhandle where vis
satellite imagery has some convective clouds as well. At the
surface, low pressure was centered near Omaha with a second
developing low over southeastern Colorado. A cold front extended
east of the second low across southwestern Kansas, northeast into
southeastern Nebraska. As of midday temperatures across Nebraska
ranged from 31 at Alliance to 70 at Falls City. Light snow has begun
to develop across the northern panhandle over the past couple of
hours. Highway cameras have indicated some light accumulations
across northern Sheridan county around Hay Springs. Across western
and north central Nebraska under cloudy skies, 3 PM CST temperatures
ranged from 37 at Valentine, Thedford and Ogallala, to 43 at
O`Neill.
&&
.SHORT TERM...(This evening through Friday)
Issued at 340 PM CST Thu Nov 17 2016
Tonight and Friday...Snow accumulations and impacts
from the approaching winter storm are the main forecast concern over
the next 24 hours. Through Friday, a strong upper level low and
associated surface low will track from eastern Colorado into the
upper Mississippi valley. Accumulating snows and strong winds will
be the main impacts to the forecast area over the next 24 hours. The
latest NAM12 solution this morning has now trended further east
toward the GFS solution with its heaviest area of snow across the
eastern portion of the forecast area. Further support for this shift
lies with the latest RAP and HRRR solutions as well. Also, the
models do agree on a strong potential for convective precipitation
ie. thunder snow which could lead to some better than 1 inch per
hour snow accumulations. That being said, with the more eastward
shift in the models this morning, went ahead and added Lincoln and
Custer counties to the winter storm warning and increased snow
accumulations. For the remainder of the forecast area, felt snow
accumulations were a tad light and increased them across the board.
This was a result of a earlier change over from rain to snow
forecast for tonight. Temperatures today have remained steady in the
30s to around 40, not the 40s to near 50 as was forecasted
overnight. These cooler temps should facilitate an earlier change
over from rain to snow, thus the higher amounts. With the increases
in accumulations, snow totals with this system will range from
around 2 inches in the far southwest and southeastern panhandle to
around 7 inches in the northeastern forecast area. For most of the
forecast area, these amounts are sub warning criteria, however strong
winds behind the exiting system are a major concern, as well as the
blowing and drifting snow threat. Also, this is the first major
winter storm of the season, so feel warning headlines remain
justified here.
Snow will taper off to flurries from southwest to northeast
overnight tonight through mid morning Friday. Very strong
northwesterly winds will impact the forecast area with the strongest
winds expected from central into north central Nebraska and points
east. In these areas, bufkit soundings indicate a strong potential
for 50+ MPH wind gusts centered around 12z Friday morning. This will
produce considerable blowing and drifting snow which will make for a
bad commute Friday morning. Winds will begin to diminish Friday
afternoon with the blowing snow threat winding down Friday
afternoon. Highs Friday will be cool as readings struggle to get out
of the lower 30s.
.LONG TERM...(Friday night through Thursday)
Issued at 340 PM CST Thu Nov 17 2016
Friday night will be cold as a fresh snow pack will combine with
clear skies and light winds. Coldest night this fall for all with
teens and even some single digits possible in favored cold spots.
Although a chilly start to the day on Saturday a nice rebound of
temps as ridging builds in for the weekend. Highs still a little
below normal as the snow cover dampens the warming, although areas
that see some snow free ground may be a little warmer than going
forecast.
Warming trend continues on Sunday and Monday with highs in the 40s
and 50s, coolest across north central Neb as cold air recycles into
the region.
Next system ejects across the Rockies late Monday into Tuesday. A
much warmer system than current system with precip type now looking
at more rain than snow, although that which falls overnight could be
a mix.
This is another short lived system with a rebounding ridge for Wed
into the Thanksgiving holiday. Highs in the 50s with lows in the 20s
to around freezing.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1210 PM CST Thu Nov 17 2016
Winter storm to impact the terminals over the next 24 hours. MVFR
cigs have already arrived and expect conditions to deteriorate
later today. Rain is expected to begin with a quick transition to
snow. In addition to the precip, gusty northernly winds are
expected. The combination of snow and winds will reduce
visibility to less than 1 mile at times overnight. Conditions
slowly improve in the morning as precipitation ends and cigs
begin to lift.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 6 PM CST /5 PM MST/ Friday for
NEZ022-056>058-069>071.
Winter Storm Warning until 6 PM CST /5 PM MST/ Friday for
NEZ004>010-023>029-035>038-059-094.
&&
$$
SYNOPSIS...Buttler
SHORT TERM...Buttler
LONG TERM...Masek
AVIATION...Masek
Area Forecast Discussion
National Weather Service SAN ANGELO TX
320 PM CST Thu Nov 17 2016
.SHORT TERM...
(Tonight and Friday)
Main concern for tonight is the threat for thunderstorms in the
Northwest Hill Country as the cold front approaches. Latest NAM12
model soundings show decent Most Unstable CAPE values for this time
of year between 09z and 12z. The values ranged from 1500 to 1700
J/KG near Junction with dewpoints in the low to mid 60s, but the CIN
of -30 to -50 may be enough to sustain the capping inversion. HRRR
and the Texas Tech WRF show a fine line of precipitation forming,
but nothing of consequence.
At any rate, if a storm can break through the CAP, it could produce
an isolated strong thunderstorm, with some small hail and gusty
winds tomorrow morning, mainly along and southeast of a line from
San Saba to Mason to Junction. Will highlight this threat in the
Hazardous Weather Outlook. Have continued the trend of chance Pops
for the Northwest Hill Country.
The cold front should slide across the area between Midnight and 6
AM tonight, sweeping the low level moisture east and ushering in
cool and breezy north winds to the region tomorrow. Highs on Friday
will only climb into the upper 50s north to the low to mid 60s
south.
.LONG TERM...
(Friday Night through Sunday)
As surface high pressure settles over the area this weekend along
with a dry airmass, ideal radiational cooling will be in place
Friday and Saturday nights, especially south of the I-20
corridor. The MEX guidance is still indicating lows in the upper
20s to lower 30s across across the Northwest Hill Country and
Heartland on west along the I-10 corridor by Sunday morning. The
first freeze of the season may be possible across these areas.
Going with lows in the lower to mid 30s, with upper 20s possible
Sunday morning, especially low lying areas and river valleys.
Going to continue the SPS for possible freezing temperatures and
areas of frost. Highs will be in the upper 50s to mid 60s.
(Sunday Night through Thursday)
For early next week, expect a warming trend and mainly a dry
forecast. A few showers and thunderstorms are possible Tuesday
across the Big Country and Heartland. The temperatures will be
little cooler Wednesday due to the passage of a cool front. Also,
expect gusty south to southwest winds on Tuesday. Highs will be in
the upper 60s to mid 70s, with lows in the 40s and 50s.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 51 60 34 57 / 10 0 0 0
San Angelo 53 62 35 59 / 20 5 0 0
Junction 58 65 35 60 / 20 30 0 0
Brownwood 55 61 36 57 / 30 10 0 0
Sweetwater 49 58 34 56 / 5 0 0 0
Ozona 51 61 34 58 / 10 5 0 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
26/21
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
232 PM CST Thu Nov 17 2016
.SHORT TERM...(This evening through Friday)
Issued at 229 PM CST Thu Nov 17 2016
This afternoon, a surface front was located across the northwest
portion of the CWA creating both a temperature and wind gradient
across the area. Ahead of this front, southerly winds have been
gusty with sustained winds near 25 mph and gusts up to 45 mph in
some areas. Near this boundary, winds are near calm with light
northwesterly winds behind the front. Due to the progression of
this low and observations from this afternoon, have opted to keep
the wind advisory, but not expand it to any areas generally north of
I-35. As the main mid-level trough digs across the Central Plains
this evening and overnight, another surface low builds into
southwestern Kansas and will move across the state by early morning
bringing the surface front through northeast Kansas. An increase of
winds in east central Kansas ahead of this secondary low is
expected, although with winds only on the cusp of advisory criteria
today, have decided not to extend the advisory with only gusts up to
40mph possible through the evening. Post frontal precipitation is
possible with the best chances in very north central Kansas as
precipitation wraps behind the departing low. While the NAM does
show light precipitation forming along the trough very early morning
near the KS/MO boarder, this seems to be the outlier. Temperatures
overnight will vary due to the frontal passage with mid 30s expected
in north central Kansas and mid-40s near east central Kansas. For
tomorrow, colder temperatures stream in behind the front along with,
once again, strong winds. Sustained winds near 20 mph with gusts up
to 40 knots will be seen throughout the morning and afternoon.
Overcast to broken skies in the morning look to linger on through
the day. Highs tomorrow will be even slightly below average in the
mid 40s to low 50s.
.LONG TERM...(Friday night through Thursday)
Issued at 229 PM CST Thu Nov 17 2016
Expansive high pressure will build southward behind the departing
system this weekend. Cooler temperatures and light winds will allow
lows to drop into the 20s both Sat and Sun morning. Return flow
develops on Sunday causing the temperatures to moderate back to near
normal with highs in the highs in the 50s and lows in the 30s. Weak
ridging aloft moves across the central US also keeping temperatures
from dropping. Towards mid week quasi-zonal flow aloft brings a few
shortwaves over the region. Both systems do not appear deep enough
to tap into the arctic air, which is mild anyway. The system on
Tuesday tracks fairly close by and some models are producing a
decent amount of QPF, while the system on Friday appears to be much
drier. Some of the models are showing some instability on Tuesday
therefore thunder will be possible.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1120 AM CST Thu Nov 17 2016
VFR is expected through the majority of the period, with the main
concern being strong, gusty winds this afternoon and late tonight
through tomorrow. With a front intersecting the area, winds ahead
of this feature will remain strong and gusty with gusts up to 35
knots seen this afternoon. MHK may have a brief decrease in winds
as the trough nears, before gusting back up though the end of the
period. LLWS is possible for a brief time if winds at the surface
do decease near TAF sites, but this mention has been left out this
issuance. Lower clouds will move in tomorrow morning at 12Z at MHK
and 15Z at TOP/FOE behind the front, with the best chances for MVFR
conditions seen at MHK.
&&
.FIRE WEATHER...
Issued at 229 PM CST Thu Nov 17 2016
Very high fire danger conditions today as gusty southerly winds
continue at 20 to 30 mph sustained with gusts up to 40 mph through
early afternoon. Main uncertainty lies with dewpoints. Due to the
poor handling of dewpoints mixing heights from guidance yesterday,
trended towards the drier HRRR and RAP solutions for this type of
setup. Combined with the warm temps in the upper 70s to near 80
degrees, could only calculate minimum humidity values in the lower 30
percent range, which occurs during the late afternoon period. Winds
however weaken some by this time as a prefrontal sfc trough bisects
the area. Still should see winds in excess of 20 mph sustained for
eastern and far northeast Kansas during this time, however RH values
are forecast to not reach 20 percent. For this forecast, will
mention the very high fire danger wording, but do not plan on
issuing headlines.
Winds on Friday will be sustained in the 20-30 mph range with
occasional gusts to 35 mph or stronger out of the northwest.
Temperatures will be much cooler and this will keep RH values in
check with MinRH probably holding in the 35 to 43 percent range.
While this has been as strong storm system, it will result in
little to no precipitation for the local are so any fuels should
still be rather dry through Friday.
The next good chance for rain comes early Tuesday morning through
Tuesday night. This appears to be a pretty good chance for
widespread rain showers.
&&
.CLIMATE...
Issued at 310 PM CST Tue Nov 15 2016
Current Record High Temperatures
----------------------------------------------------------
November 17
Topeka 76
(year) (1999)
Concordia 76
(year) (1943)
Current Record Warm Low Temperatures
----------------------------------------------------------
November 17
Topeka 56
(year) (1941)
Concordia 57
(year) (2004)
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 6 PM CST this evening for KSZ040-054>056-058-
059.
&&
$$
SHORT TERM...Heller
LONG TERM...Sanders
AVIATION...Heller
FIRE WEATHER...Prieto
CLIMATE...Prieto