Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/11/19
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
536 PM CST Sun Feb 10 2019
.UPDATE...
Issued at 528 PM CST Sun Feb 10 2019
Made some adjustments to precip onset time tonight and Monday
morning. Otherwise, no further changes were needed this evening.
&&
.SHORT TERM...(This Evening through Monday Night)
Issued at 250 PM CST Sun Feb 10 2019
Forecast challenges include cloud coverage through late this evening
and snow timing/coverage/amounts on Monday/Monday night and freezing
drizzle potential over the Coteau Monday morning through early
afternoon.
Currently, temperatures range from around zero to near 10 degrees
throughout the CWA. Earlier cloud-cover associated with accumulating
snow has moved off into Minnesota, leaving partial coverage of
stratus clouds around the area. And some of that cloudiness appears
to be dissipating as it gives off one last burst of very light
snow/flurries. Reports trickling in suggest that anywhere from 1 to
3 inches of fluffy snow (generally less than a tenth of an inch
water equivalent in this snow) has fallen today. Winds have a
predominant northeasterly direction and are running generally 5 to
15 mph.
Overnight, additional low clouds are expected to develop/move north
over the region as a low pressure system over Montana/Idaho heads
this way. With it being cold enough (even in the stratus layer) to
activate ice, continuing an isolated flurry mention out of this
forecast low stratus until the better WAA-forced precipitation gets
going on Monday. That being said, both the RAP and 12Z NAM12 output
in BUFKIT today supported the notion that the temperature in the
(deep enough to produce drizzle) stratus layer may warm up enough
out over the Prairie Coteau and points east Monday morning to
produce some freezing drizzle instead of flurries and potentially
persist into early Monday afternoon. But, once mid-level saturation
(within the DGZ) from the WAA-forcing sets up over the east, the
temperature of the low level stratus becomes moot, and p-type would
just be all snow. It`s not clear if the freezing drizzle potential
will reach much farther west or north of the Coteau Monday morning.
For now, concentrating the freezing drizzle mention out over the
Coteau over into west central Minnesota.
There has been a general back-peddling on qpf/snow amounts in the
models for three days in a row now, and tomorrow/night`s
precipitation event now looks to be a generally light snow event
with amounts ranging from an inch or two across the Missouri River
valley to 2-4 inches across the SoDak/MN border area. Wind speeds
have continued to decrease as well for this event, with generally 15
to 25 mph winds expected. This yielded some "patchy blowing snow"
mention on Monday. The WAA and surface/PBL winds out of the
southeast on Monday are expected to produce somewhat warmer
temperatures, with readings up into the teens and 20s (sadly, this
is still below climo normal for this time of year). The low level
CAA Monday night that will be lagging behind the snow event by just
a few hours will re-assert more of the much below normal cold air
into the CWA.
.LONG TERM...(Tuesday through Sunday)
Issued at 250 PM CST Sun Feb 10 2019
Storm system will be departing the area to the east on Tuesday, with
another shot of cold air moving into the region. Given how cold the
925mb temps are, it seemed SuperBlend might be a little too warm for
highs on Tuesday. Also noticed several models were colder than
SuperBlend, so did basically a 50/50 split between SuperBlend and
the colder feel of the ADJECE guidance. Temperatures for the rest of
the extended period were left as inherited. For winds, increased
things a bit on Tuesday on the back side of the departing storm
system. Also used more of the higher CONSMOS/EC feel for winds
during the Thursday/Thursday night system.
As for precipitation, the main player is this system that moves
through Thursday into Thursday night. Model agreement has become
better as far as timing goes, and they all appear to bring more
light to moderate snow accumulations to the area. As of now, it
would appear higher accums may be across the western CWA, but still
much to sort out before we get to that point as it`s still several
days away.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday Evening)
Issued at 528 PM CST Sun Feb 10 2019
A mix of cigs this evening is expected to become mostly IFR as
snow and blowing snow move through the region on Monday.
Conditions will improve to MVFR when the snow ends toward the end
of the period.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...Wise
SHORT TERM...Dorn
LONG TERM...TMT
AVIATION...Wise
Area Forecast Discussion
National Weather Service Buffalo NY
954 PM EST Sun Feb 10 2019
.SYNOPSIS...
A weak front will move southeast across the area tonight with spotty
light snow and very minor accumulations. A stronger storm system
will move into the eastern Great Lakes late Monday night and
Tuesday. This will spread accumulating snow into the area, which
will then change to a wintry mix and even just rain in some areas
later Tuesday before changing back to snow by Wednesday as colder
air moves back into the region.
&&
.NEAR TERM /THROUGH MONDAY/...
Light snow has moved into the western Southern Tier this
evening. Dry air in place is keeping light snow from reaching
the ground across the rest of western NY. This will soon change
as isentropic lift and mid- level moisture continue to
increase. Moisture advection will prove just efficient enough
to properly saturate the column with enough depth to translate
into a period of light snow across western and north central NY.
Model guidance shows a notable decrease in forecast magnitude
and duration of mid level upward vertical motion across the
area. The short residence time of both greater moisture depth
and meaningful forcing generally 4 to 6 hours will keep
accumulation potential limited to an inch or less for most
locations, largely centered between 9 pm and 3 am. There may be
a brief period of very minor lake enhancement along the south
shore of Lake Ontario late tonight when 925-850mb flow becomes
northeast from Monroe to Niagara counties, but any enhancement
to accumulations will be minimal.
As we get later into the overnight period and into Monday morning
profiles showing mid level moisture decreasing causing a marginal
thermal profile which become less favorable in supporting mid level
ice nucleation, therefore become increasingly susceptible to a
possible mix or switch to supercooled droplets. This may introduce a
window for the potential for some freezing drizzle as moisture
quality only slowly diminishes with time below 5k feet. Any ice
accretion potential likely minimized by the limited overall coverage
and intensity, while also falling on top of freshly fallen snow.
Later shifts will need to monitor how this unfolds.
A break in the precipitation is expected for most of Monday as
moisture in temporarily shunted south of the area as drier air
around high pressure over western Quebec works into the area. This
will allow for some clearing skies, especially for areas east of the
Finger Lakes. Temperatures will be seasonable with highs in the 20s
to lower 30s across southwestern New York.
&&
.SHORT TERM /MONDAY NIGHT THROUGH THURSDAY NIGHT/...
...Winter Storm Warning Issued for the North Country...
During the first 36 hours of this period...the 12z/10 guidance suite
remains in good agreement on ejecting an increasingly negatively
tilted upper level trough northeastward across the Plains States...
Great Lakes...and into the Northeastern States. Meanwhile at the
surface...an attendant initial cutter-type low will steadily deepen
as it tracks from the south-central Plains to the central Great
Lakes Monday night and Tuesday...with the low then passing by a
little to our north and filling Tuesday night as it begins
transferring its energy to a secondary surface cyclone developing
off the New England coastline. This system will be accompanied by
increasingly plentiful moisture and deep forcing for ascent as it
approaches and passes through our region...resulting in light
precipitation initially developing into portions of far western New
York Monday night...before overspreading the remainder of the region
and becoming steadier/heavier on Tuesday...then continuing right on
through Tuesday night.
With respect to precipitation type...our airmass will initially be
cold enough for this to start off as some light snow Monday night
and early Tuesday morning. As we move through Tuesday and Tuesday
evening though...a surge of milder air...first aloft and then at
the surface...will push into western New York out ahead of this
system`s trailing cold/occluded front. This will result in the snow
giving way to a wintry mix and eventually a cold rain for the bulk
of the area south of Lake Ontario...where surface temperatures
currently look to climb into the mid to upper 30s later Tuesday
and Tuesday evening. Further to the northeast colder air will hang
tough across the North Country...resulting in the precipitation
primarily remaining in the form of snow through Tuesday evening.
As we push through the second half of Tuesday night and Wednesday
morning the surge of milder air will try to push further northeastward...
but will become increasingly muted and pinched off on both sides as
the cold/occluded front pushes across western New York...and as the
developing secondary surface low off the New England coastline wraps
colder air back into our region from the northeast. The end result
of all this will be rain mixing with and then changing back to snow
across western New York...while mixed precipitation MAY push into
portions of the North Country for a short period (mainly south of
Tug)...before also transitioning back to all snow. Lingering
wraparound moisture...cold air advection...and upsloping behind the
consolidating low will then lead to continued lighter snow through
the second half of Wednesday.
In terms of potential snowfall amounts...at this still-early juncture
it still appears that the best potential for a significant (i.e. warning-
criteria) snowfall will lie across the far eastern Finger Lakes/Eastern
Lake Ontario region and especially the North Country...where the potential
for any mix will be lowest and the briefest...and consequently the precip
should remain in the form of snow the longest...potentially leading
to total snowfall accumulations of 12 to 18 inches over a rough 24
to 36 hour period. Have thus upgraded the Winter Storm Watch for
Jefferson and Lewis counties to a Winter Storm Warning. Elsewhere...
snowfall amounts should decrease with increasing southwestward
extent owing to the progressively earlier arrival of the milder air
and the attendant wintry mix/changeover to rain...though current
projected snowfall amounts and the potential for a wintry mix of
sleet/freezing rain will still likely eventually warrant Winter
Weather Advisories.
As has been pointed out previously...it goes without saying that all
of this remains highly dependent upon the exact track/strength of the
initial primary low and how quickly the transfer of energy to the
secondary coastal system takes place. A more northwesterly track to the
primary low...a stronger primary low...and/or a delayed transfer of
energy to the coastal system would all point to a warmer overall
scenario and less snow areawide...while the opposite conditions would
favor a colder scenario and more snow overall.
One other hazard this system could present may be a couple rounds
of stronger gusty winds. The first of these could come in the form
of strong southeasterly downslope winds along the Lake Erie shoreline
during the day Tuesday...with the NAM/GFS (both of which have a stronger
primary low following a more northwesterly track...and consequently a
stronger associated southeasterly low level jet) currently suggesting
this possibility. The second would be a possible round of stronger
west-southwesterlies/westerlies across western New York following
the passage of the trailing cold/occluded front later Tuesday night
and Wednesday morning...as has been consistently advertised by the GFS
over the past several days. While the potential for both will greatly
depend on the track/strength of the primary low and how quickly it
transfers its energy to the secondary coastal system...at this point
at least some advisory-worthy winds appear a possibility during both
of these time frames...so will add a mention of both to the HWO.
Following the passage of this system...lingering scattered to numerous
snow showers (most numerous downwind of Lake Ontario due to lake
enhancement) will diminish from west to east Wednesday night as high
pressure and drier air build across our region...and as warm air
advection commences aloft. Otherwise drier and quieter conditions
can be expected...with overnight lows settling into the upper teens
to lower 20s.
On Thursday the surface ridge axis will slide off to our east...while
yet another notable southern-stream system pushes into the central
Plains states...thereby placing our region within a broad southwesterly
flow of milder air. This will allow high temperatures to recover back
to above normal fairly quickly...with highs returning to the lower to
mid 30s across the North Country and to around 40 south of Lake Ontario.
Meanwhile the bulk of the day should be dry...with the overall warm
air advection regime/development of a warm frontal boundary possibly
leading to just a few spotty light rain or snow showers along and
north of the I-90 corridor.
Finally...during Thursday night the surface low will make its way
further northeastward into the Upper Midwest. Continued broad warm
air advection well out ahead of this system may support some additional
scattered rain and snow showers across our region...along with milder
(and mainly evening) lows ranging from the mid 20s across the North
Country to the mid 30s across western New York.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
It will be quite unsettled over our forecast area for the bulk of
this period...as a very active southern stream within a split flow
will pound the area with yet ANOTHER significant storm system. In
fact...there could very well be another round of headlines. The
active southern branch of the jet should come as no surprise to
those familiar with ENSO though...as Pacific based storms within
moderate to strong El Nino`s often make their away across the
southern half of the country before making the turn to the Great
Lakes or Northeast. There is currently a moderately strong El Nino
in place across the Equatorial Pacific. Now the day to day details.
A deepening cyclone will track northeast across the mid western
states on Friday...with its associated warm frontal boundary
extending across the western counties of our forecast area. While
there is high confidence in this general scenario...the subtlety as
to whether the warm front can actually move past the south shore of
Lake Ontario is still being debated by the various guidance
packages. Why is this important? Temperatures Friday will approach 50
across the Southern Tier in the wake of said front...but there will
be a tight thermal gradient to Lake Ontario...with temperatures near
the south shore and also over the Eastern Lake Ontario region
possibly having trouble climbing out of the 30s. Both the ECMWF and
particularly the GFS operational runs suggest the colder solution
for these areas. This will present the headache of mixed
precipitation... which should be found across the bulk of the region
for at least the early morning. The mix of rain or wet snow could
also include some freezing rain...but from this range...will avoid
complicating an already complex system.
That all being said...mixed precipitation will spread northeast
across our forecast area during the course of Friday. Fairly
widespread rain should be found west of the Finger Lakes and also
for the Thousand Islands region for the afternoon.
The deep storm system will advance to western Lake Erie by Friday
evening where it should begin the process of transferring its energy
to the coast. As we have already seen several times in the past few
weeks...ANOTHER Miller B cyclogenetic event. Watch for closed mid
level storms with a negative tilt for keys to these events...as they
are often more telling than the actual MSLP output. For what its
worth...the ECMWF seems to do very well with these patterns. In this
particular case though...both the ECMWF and GFS based ensembles seem
to be in solid agreement. In fact...the GFS has been locking in on
this solution for the past 3 days. This only adds to the very
confidence in the pops...which will be restrained to just 90 for
better collaboration. Deep lift will be provided by plummeting
heights...a divergent UL flow...and significant forcing from being
under the RR entrance region of a 100kt jet over Quebec. This lift
will be applied to a deep plume of sub tropical moisture...so its
possible that rainfall amounts could exceed a half inch.
By Saturday morning...the transference of energy to the New England
coast should be nearly complete. This will leave a general weakness
in the pressure field over our forecast area where the primary low
would be. While we will lose our deep forcing...there will still be
enough lift from convergence within the mid level trough to support
fairly widespread rain and snow showers that will change to all snow
showers by the afternoon. Given the pressure gradient on the
backside of the sub 980mb secondary low...it should become rather
windy over our area as well.
Saturday night and Sunday...the secondary storm will chug across the
open St Lawrence to eastern Quebec and eventually the Labrador Sea.
A deep cyclonic flow of moist...increasingly cold air will keep the
likelihood of snow showers in place for our forecast area...with
lake enhancement expected southeast of both lakes...especially Lake
Ontario.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
Mid level clouds will continue to thicken and lower ahead of weak
frontal boundary tonight. Light snow will track across western
NY tonight reaching KIAG,KBUF, KROC and KART by 4z. This will
cause some MVFR flight restrictions and spotty IFR vsbys. Snow
will be spotty and may cause flight conditions to change
frequently into Monday morning. Light snow may transition to
freezing drizzle across western NY through Monday morning. This
may also keep conditions sub- VFR. Low clouds will likely stick
around through most of the afternoon resulting in MVFR
conditions.
Outlook...
Monday night...Deteriorating to IFR late with snow developing.
Tuesday...Areas of IFR with snow changing to wintry mix and then
rain.
Wednesday...Areas of IFR with snow likely.
Thursday and Friday...Mainly VFR.
&&
.MARINE...
Northeast winds will increase late tonight and Monday as the
pressure gradient tightens between high pressure over Quebec and low
pressure moving into the Upper Midwest. This will bring another
round of Small Craft Advisory conditions to the south shore of Lake
Ontario.
The easterly winds will continue to strengthen Monday night and
Tuesday as the low approaches. This low will cross the eastern Great
Lakes later Tuesday night, with winds becoming southwest Wednesday
with Small Craft advisory conditions continuing. Gales force winds
are possible on Lake Ontario.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Winter Storm Warning from 10 AM Tuesday to 10 PM EST Wednesday
for NYZ007-008.
Winter Storm Watch from Tuesday morning through Wednesday
evening for NYZ005-006.
MARINE...Small Craft Advisory from 6 AM Monday to 10 PM EST Tuesday for
LOZ042-043.
&&
$$
SYNOPSIS...TMA
NEAR TERM...HSK/TMA
SHORT TERM...JJR/RSH
LONG TERM...RSH
AVIATION...HSK/TMA
MARINE...HSK/TMA
Area Forecast Discussion
National Weather Service Fort Worth TX
935 PM CST Sun Feb 10 2019
.UPDATE...
/Tonight/
Only notable change with this update is the increasing of PoPs
over parts of western North Texas, where another subtle shortwave
impulse is yielding a band of generally light rain this evening.
The expectation is for this band to slowly shift northeast, while
a low-level warm conveyor gradually matures along/east of the I-35
corridor after midnight. Rain chances will accordingly increase
here as well.
Visibilities have been slow to fall with any consistency across
the region, perhaps due to some veered low-level flow in the wake
of a subtle mid/upper trough departing to our north over
Oklahoma. As such, no plans to hoist a dense fog advisory anywhere
at this time. However, in tandem with the aforementioned
maturation of a warm-advection corridor, hi-res/probabilistic
guidance still suggest visibilities may fall close to advisory
criteria across parts of East Texas and perhaps near the Red
River after midnight. These trends will be monitored accordingly.
Picca
&&
.AVIATION... /Issued 612 PM CST Sun Feb 10 2019/
/00Z TAFs/
Continued poor flying conditions expected through daybreak. Main
challenge remains the timing of category changes for both CIGs and
VSBYs.
With one weak/low-amplitude impulse skirting portions of northwest
Texas at present, some enhancement of warm-air advection across
our region has kept CIGs generally around LIFR levels. Expect
these ceilings to remain around 002-004 through 02-03Z. They may
rise slightly to 004-008 around 03-06Z, but confidence in this
scenario is not particularly high. Likewise, VSBYs may improve
slightly by 02-03Z. This may occur perhaps even sooner but given
nightfall and the likely presence of unresolved upstream impulses,
think a TEMPO for IFR VSBY is still warranted through 03Z.
Most guidance and observational evidence then suggest conditions
should worsen further around 06-07Z, in response to another surge
in low-level moistening/ascent. Maintained mention of occasional
LIFR, and there is some possibility CIGs/VSBY could fall to near
airport mins after 06Z. However, the worst conditions may remain
just east of all TAF sites, and confidence in VLIFR is too low to
include in TAFs.
Drying above the surface will become more earnest around 12-15Z
Monday. Therefore, continue to advertise a slow improvement trend
through the morning. Do think it will be a gradual improvement
(and not particularly fast) owing to persistent southwesterly
flow aloft and remaining near-surface moisture. As surface flow
increases and veers more southwesterly through the afternoon,
though, conditions should rise to MVFR and eventually VFR. There
is some potential for VFR CIGs to be delayed until after 12/00Z at
KDFW, however.
Picca
&&
.SHORT TERM... /Issued 309 PM CST Sun Feb 10 2019/
/Tonight/
The main concerns through the overnight hours will be periods of
drizzle, light rain and fog.
Surface analysis revealed that southerly flow was beginning to
envelop much of the area this afternoon in response to lee-side
surface pressure falls to the north. Rich low level moisture
remains confined to the upper TX coast at this time, but as
surface flow continues to veer, some of this moisture should make
a run northward into parts of North and Central Texas. The warm
and moist advection should result in near steady or rising
temperatures. With isentropic upglide expected to continue, there
will be a a continued risk for light measurable rainfall along
with drizzle and some fog. Increased surface moisture, per RAP
soundings, into this airmass signals more of an advection fog type
setup tonight. A consensus of hi-resolution guidance supports
reduced visibility down to 1/2 a mile and I wouldn`t be surprised
to see some areas of dense fog...especially near and east of I-35.
For now, we`ll hold off on any advisories, but one may be needed
late tonight into early Monday.
Otherwise, temperatures should remain in the 40s areawide.
Bain
&&
.LONG TERM... /Issued 309 PM CST Sun Feb 10 2019/
/Monday Onward/
Areas of fog are likely to continue into Monday morning as
south winds usher ample moisture northward into a cooler airmass
already in place. Some warming will occur throughout the day via
warm advection as strong low-level southerly flow prevails. While
one wave of precipitation will be exiting the area around
daybreak, another will develop off to the west later in the day as
an approaching shortwave trough swings through the Plains while
becoming negatively tilted. This will cause mid-level lapse rates
to steepen via cooling during the afternoon and evening hours,
which may result in a few thunderstorms near or east of I-35.
Instability is expected to be very limited, which should confine
hazards to occasional lightning or at most some small hail across
our eastern zones. As the upper trough`s associated surface low
accompanies it eastward late Monday, a cold front will be pulled
through the region, scouring moisture while bringing rain chances
to an end from west to east.
In wake of Monday`s front, cooler and dry conditions are expected
to prevail through the middle portion of the week. Temperatures
will generally be within a few degrees of seasonal normals as a
slow warming trend occurs through Wednesday. Zonal flow aloft will
prevail throughout the time period, and moisture will largely
remain scoured from the forecast area.
By Thursday, a dynamic storm system is expected to dive into the
Plains, prompting strong lee cyclogenesis. A deep surface low will
develop through southeastern Colorado and drift eastward through
Kansas and Oklahoma. This surface pattern will result in veered
low-level winds across our forecast area, which should make for a
warm and breezy day as the pressure gradient tightens. With west
winds and increased downsloping, 70s are likely area-wide and
some of our western zones may flirt with 80 degrees. Moisture
return will be fairly limited with this setup, so despite the
dynamic storm system, precipitation may be confined to some warm
advection showers east of I-35 Thursday afternoon. At this point,
it appears most areas will remain rain-free. The strong and
rather deep southwesterly flow should keep a stout lid on any
surface- based convective attempts with what meager moisture will
be available in the first place. Given the windy and warm
conditions with low RH values along with limited rainfall in
recent weeks, there may end up being some elevated fire conditions
Thursday afternoon west of I-35.
Thursday night and Friday morning, this system`s strong cold front
will push through the forecast area turning winds abruptly to the
north at 20-30 mph. At this stage, it appears moisture will be
too meager to support any precipitation along the front. Strong
cold advection and post-frontal stratus should keep temperatures
20 or more degrees cooler than Thursday with highs likely only in
the 40s or lower 50s. The cool weather will continue heading into
next weekend, with temperatures expected to be around 10 degrees
below normal on Saturday.
-Stalley
&&
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 43 65 40 58 35 / 60 40 20 0 0
Waco 45 66 43 59 35 / 40 60 20 0 0
Paris 41 62 40 54 32 / 90 90 40 0 0
Denton 42 64 38 58 33 / 60 40 20 0 0
McKinney 43 64 40 56 33 / 70 60 20 0 0
Dallas 43 65 41 58 36 / 60 50 20 0 0
Terrell 43 64 40 57 33 / 80 70 30 0 0
Corsicana 43 65 42 57 34 / 70 60 30 5 0
Temple 45 66 43 60 35 / 40 60 20 0 0
Mineral Wells 43 65 36 58 33 / 60 30 10 0 0
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
11/30
Area Forecast Discussion
National Weather Service Hastings NE
552 PM CST Sun Feb 10 2019
.SHORT TERM...(This evening through Monday Night)
Issued at 317 PM CST Sun Feb 10 2019
The main concern with this forecast issuance is the freezing
drizzle that is expected late tonight through Monday.
This evening into tonight, we will see winds gradually become
easterly to southeasterly. This upslope flow accompanied with
isentropic lift ahead of another approaching shortwave should be
sufficient to produce widespread low stratus and light
precipitation by Monday morning.
Model soundings continue to be very indicative of freezing
drizzle. The HRRR shows a fully saturated profile from the surface
to nearly 750mb by 6am Monday, with absolutely no saturation in
the dendritic layer. Most all models continue to output 0.05-0.10"
of QPF with this activity as well. I think the 18Z HRRR solution
looks very reasonable with regards to timing and coverage/impacts.
The advisory has been expanded southward as it appears that the
entire area will see at least light icing Monday morning. By
Monday afternoon, things become a little more uncertain across
southern areas though. Temperatures have trended colder, but
afternoon highs may still rise above freezing...especially in
north-central Kansas. As a result, we may just see drizzle and
reduced impacts for several hours before temperatures fall back
below freezing in the evening.
Models continue to show a brief window for light snow during the
afternoon and evening, but accumulation will be very minimal for
most locations. Northeastern portions of the forecast area will be
the heaviest, but still should be around one inch or less.
Precipitation will wind down from west to east as the upper level
trough axis moves through Monday evening.
.LONG TERM...(Tuesday through Sunday)
Issued at 317 PM CST Sun Feb 10 2019
Dry conditions prevail Tuesday and Wednesday as the trough
deepens over the Great Lakes and we see rising heights aloft.
Temperatures are also expected to make a nice recovery by
Wednesday, with forecast highs now ranging from the low 40s to mid
50s. Winds will be relatively light, so this appears be the
nicest day of the week.
The next disturbance is expected to move through on Thursday
afternoon into Friday morning. This appears to be a quick-moving
wave, but models are still showing that it could produce a swath
of significant snow for portions of the area. Details on this
system will hopefully come into better focus over the next few
days.
This system will also usher in another shot of cold air, which,
when coupled with the gusty north winds on the back side of the
low, may push wind chills down into the -10 to -20 range across
portions of Nebraska.
Cold weather will continue Saturday and Sunday. While not
completely dry, the the overall threat for significant snow
appears relatively low as we head into next weekend.
&&
.AVIATION...(For the 18Z KGRI/KEAR TAFS through 18Z Monday)
Issued at 1126 AM CST Sun Feb 10 2019
Generally poor conditions are expected at both terminals through
the period as MVFR/IFR conditions this afternoon are only
expected to worsen and become LIFR overnight as fog is expected to
develop over the next couple of hours as CIGS lower...and
freezing drizzle is expected to become widespread before daybreak.
While this drizzle may transition to snow...especially at KEAR
late in the day...kept freezing drizzle in both TAFS from 11/10Z
through the end of the period...with a slight improvement in CIGS
late in the day. Winds overall will be less than 12 KTS through
most of the period and generally out of the east...and shifting
from the north late in the day.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...Winter Weather Advisory from 3 AM Monday to midnight CST Monday
night for NEZ039>041-046>049-060>064-072>077-082>087.
KS...Winter Weather Advisory from 3 AM Monday to midnight CST Monday
night for KSZ005>007-017>019.
&&
$$
SHORT TERM...Mangels
LONG TERM...Mangels
AVIATION...Mangels
Area Forecast Discussion
National Weather Service Green Bay WI
545 PM CST Sun Feb 10 2019
Updated aviation portion for 00Z TAF issuance
.SHORT TERM...Tonight and Monday
Issued at 519 PM CST Sun Feb 10 2019
The latest RAP analysis and satellite/radar imagery show low
pressure centered over western Kansas and a surface trough
extending northeast from just south of La Crosse to around
Manitowoc. Meanwhile, an elongated shortwave trough is moving into
western WI early this afternoon. In the warm advection regime
ahead of the shortwave, snowfall expanded across northeast WI by
early in the afternoon, after mid-level fgen contributed to a snow
band that produced 1-3 inches across the Highway 29 corridor
during the morning. The shortwave will continue to move northeast
from southwest MN across northern WI this afternoon, and should
see an uptick of snowfall intensity at locations which were not
positioned under the snow band earlier today. Forecast concerns
generally revolve around additional accumulations with the ongoing
system.
Tonight...The shortwave will move across northern WI this evening.
Mid-level drying will be occurring behind the shortwave, so should
see the snowfall diminish from southwest to northeast during the
evening. Highest additional amounts around 1" should therefore
reside over far northeast WI, which would place total
accumulations in the 2-4 inch range at most locations, lowest
across the far north and from Wautoma to Manitowoc. A few
locations around the Highway 29 corridor, which saw more intense
snowfall in the morning, may see 5-6 inches by the time the snow
ends. No additional changes to the advisory at this time. Wouldnt
be surprise to see scattered flurries persist overnight due to
some moisture lingering above the inversion. However, will just
leave a chance along the Lake Michigan shoreline where onshore
flow will continue through the night. Under cloudy skies, temps
should not fall very much and range from around 10 degrees across
the north to 20 degrees near Lake Michigan.
Monday...The region will be between weather systems. Weak
descending motion will be occurring in the 850mb-500mb layer.
However, progged soundings indicated moisture will be trapped
beneath the inversion which should result in cloudy conditions
persisting. Wouldnt be surprised to see some flurries, or patchy
freezing drizzle occur, particularly near Lake Michigan where
easterly flow will continue. Will just leave a flurry chance near
the Lake in the morning, but will pass concerns on to the next
shift. Temps will be warmer, and range from the mid 20s in the
north to the upper 20s southeast.
.LONG TERM...Monday Night Through Sunday
Issued at 519 PM CST Sun Feb 10 2019
Main forecast concerns are the winter storm and associated
headlines Monday night into Tuesday evening, and the next system
Thursday into Friday.
Low pressure near the TX/OK panhandles on Monday evening is
expected to lift northeast and reach southeast Lower Michigan by
Tuesday evening. Developing isentropic lift ahead of the
approaching low will cause precipitation to develop Monday night.
Initially, moisture will be quite shallow, and the presence of ice
is questionable, so would expect a mix of light snow and freezing
drizzle to break out during the mid to late evening. Deeper
saturation and strong lift will likely not occur until late Monday
night or very early Tuesday (far northeast WI), and that is when
heavy snow is expected to overspread the region. A negatively-
tilted upper trof is expected to move into the region and form a
cut-off low by evening. This feature will continue the threat of
heavy snow into the afternoon, and cause at least light snow to
linger into the evening. Total snow accumulations should be in the
7 to 10 inch range, so a watch will be issued this afternoon.
Start time of the watch is problematic, as the heavy snow is not
expected until later in the night. However, offices to the west
and south are starting up between 00z-03z/Tues and the threat of
freezing drizzle will ramp up during the mid to late evening, so
have tiered our start time from 03z-06z/Tue. Continued light snow
and some blowing and drifting can be expected Tuesday evening, so
will not end the watch until 06z/Wednesday.
Another system is expected to arrive Thursday afternoon or
evening, and could bring advisory criteria snow to roughly the
southern two-thirds of the forecast area through Friday. Some
lake-enhancement could occur along Lake Michigan, resulting
in the highest amounts toward Two Rivers and Manitowoc.
Next weekend is setting up to be much quieter, with high pressure
in place.
&&
.AVIATION...for 00Z TAF Issuance
Issued at 545 PM CST Sun Feb 10 2019
Light to moderate snow will continue to impact the
region this evening before steadily diminishing overnight.
IFR/MVFR visibilities can be expected through much of this time;
however, intermittent LIFR conditions are possible under the
heavier snow showers, especially for the southern TAF sites. IFR
ceilings will likely linger through much of the rest of the TAF
period as low-level moisture remains in place. There could be some
flurries or light freezing drizzle through the day Monday, but
confidence in that happening is low. Otherwise, attention will
then turn to the potential for moderate to heavy snow overnight
Monday night through much of the day Tuesday. Significant snowfall
accumulations are expected for that time period.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until midnight CST tonight for WIZ010-
011-013-019>022-031-037>040-045-048>050-073-074.
Winter Storm Watch from Monday evening through Tuesday evening
for WIZ030-031-035>040-045-048>050.
Winter Weather Advisory until 9 PM CST this evening for WIZ018-
030-035-036.
Winter Storm Watch from late Monday night through Tuesday
evening for WIZ005-010>013-018>022-073-074.
&&
$$
SHORT TERM.....MPC
LONG TERM......Kieckbusch
AVIATION.......Cooley
Area Forecast Discussion
National Weather Service Indianapolis IN
624 PM EST Sun Feb 10 2019
.UPDATE...
The Aviation section has been updated below.
&&
.SYNOPSIS...
Issued at 255 PM EST Sun Feb 10 2019
A warm front will approach and settle near Central Indiana
tonight and Monday. This will bring snow this afternoon and
evening and rain...possibly resulting in flooding...on Monday to
Central Indiana. A FLOOD WATCH is in effect for much of Central
Indiana late tonight through early Tuesday morning.
A strong cold front will bring more rain to Central Indiana on
Tuesday along with windy conditions. Dry weather is expected for
Wednesday as High pressure arrives in the wake of the cold front.
More precipitation is expected to arrive on Thursday and Friday as
another weather system arrives in the region.
&&
.NEAR TERM /Tonight/...
Issued at 255 PM EST Sun Feb 10 2019
Surface analysis early this afternoon shows a warm front in place
across Central Indiana. Low pressure was found across the western
Missouri. Radar shows area of snow showers across Central
Indiana...and rain showers south of the warm front across
Kentucky. GOES16 shows a stream of tropical moisture set up once
again...stretching across Mexico and Texas then northeast to the
Ohio Valley.
THE GFS And NAM continue to keeps the plume of tropical moisture
streaming into the Ohio Valley tonight and into Monday. Embedded
short waves within the flow are indicated to pass through the
region. Forecast soundings and time heights both suggest a mostly
saturated column tonight...but best forcing is exiting the area
late this afternoon and arriving again toward 12Z monday. HRRR
suggests some dry air arriving from the west...limiting the
northward propagation of the precipitation this evening...leaving
the focus farther south. GFS mid levels suggest the next best
surge of moisture arriving from the southwest after 09Z. The 290K
Isentropic surface shows waning up glide this evening with
specific humidities over 4 g/kg. Given the weak warm air advection
in place...forecast soundings also show a slow warming trend
through the night...with areas along I-70 rising above freezing at
or shortly after 12Z. Thus forecast builder willing...precip type
will be snow north...mix central and Rain south tonight. Will
focus best pops through the night across the southern parts of
Central Indiana and trend toward lower pops farther north where
moisture appears to be less focused. Overnight as the next mid
level surge of moisture arrives...will trend pops upward across
the board. Given the expected warm air advection will trend highs
at or above the forecast builder blends.
&&
.SHORT TERM /Monday through Wednesday/...
Issued at 255 PM EST Sun Feb 10 2019
Active and wet weather is expected this period.
The tropical plume of moisture streaming into the Ohio Valley is
expected to persist through Monday and Monday Night.
Again...Several short waves with the moist flow will continue to
provide forcing for rainfall. Forecast soundings Monday and Monday
night remain saturated with excellent lift available. meanwhile
at the surface a warm front is expected to linger across
Kentucky...putting Central Indiana in an ideal spot for overruning
precipitation. Forecast soundings show deep moisture available
with a lower level warm air advection inversion present. Pwats
again lingering near 1 inch...quite high for this time of year.
Furthermore tropical moisture arriving aloft always seems to
enhance precip amounts. Thus will again trend pops toward 100 for
Monday and monday night. Given our recent rains and ongoing
flooding...the ongoing flood watch appear very warranted. We will
not be surprised to see flood warnings needed on Monday and Monday
Night. Given the expected precipitation will trend highs lower
than the blends and lows warmer.
On Tuesday the tropical flow will still be in place...but the
models suggest a stronger and more organized upper level wave
pushing through the plains states toward Indiana. A strong cold
front and low pressure system will accompany this wave...and
again ample moisture and plenty of forcing will be present. Thus
will again trend pops near 100. Given the expected precip will
trend temps at or below the builder blends. Furthermore...in the
wake of the front on Tuesday afternoon...strong winds will be
expected given the strong pressure gradient in place. Gusts in the
30mph range will be attained.
Strong cold air advection remains in play in the wake of the
front on Tuesday night as the upper wave departs east and diverts
the tropical flow aloft southeast. Forecast soundings show dry
air within the column arriving ...along with some trapped cold air
advection stratocu. Thus will trend toward mostly cloudy sky here
and stick close to the blend on temperatures.
High pressure an ridging is expected to build across the region
on Wednesday. However the day will begin with the mid level ridge
axis well west of Indiana and cyclonic flow still in place across
the state. This is suggested to become more anticyclonic as the
day progresses and cloud lead to decreasing cloudiness. Thus a
dry day with decreasing clouds will be expected.
&&
.LONG TERM /Wednesday night through Sunday/...
Issued at 221 PM EST Sun Feb 10 2019
The long term starts out with dry weather and upper ridging moving
across the area. By Thursday afternoon, though, a low pressure
system swings out of the plains toward central Indiana, bringing a
warm front across the area and possibly setting it up north of
here. This will bring rain again to central Indiana, starting by
Thursday night and remaining until the cold front moves through
Friday afternoon/Friday night. After cold frontal passage,
precipitation could change over to snow before dry air moves in to
bring the precip to an end. Models are in better agreement on
timing/placement with this late week system today so confidence is
back to normal level for the long range. Expect above normal
temperatures Thursday through Friday, with back to below normal on
Saturday behind the front.
&&
.AVIATION /Discussion for the 11/00z TAFs/...
Issued at 624 PM EST Sun Feb 10 2019
Extremely poor flying conditions will persist throughout the TAF
period, with LIFR or worse conditions dominating.
Guidance is very insistent on widespread 1/2SM or less
visibilities tonight in dense fog, along with widespread ceilings
around 200 feet. There is a decent chance that airfields will drop
below minima occasionally, and may stay there for extended
periods.
Winds will be less than 10KT through the period and frequently
variable.
Precipitation will be possible overnight but will likely be in the
form of rain or drizzle...potentially freezing depending on
temperatures. Any freezing precipitation will change over to
liquid during the morning hours Monday.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
Flood Watch from 1 AM EST Monday through Tuesday morning for
INZ037-039-045>049-051>057-060>065-067>072.
&&
$$
SYNOPSIS...Puma
NEAR TERM...Puma
SHORT TERM...Puma
LONG TERM...TDUD
AVIATION...Nield
Area Forecast Discussion
National Weather Service Marquette MI
549 PM EST Sun Feb 10 2019
.SHORT TERM...(This evening through Monday)
Issued at 403 PM EST SUN FEB 10 2019
WV imagery and RAP analysis indicated a shortwave trough into the
upper Mississippi Valley that supported an area of snow from eastern
MN through WI and much of Upper Michigan. At the surface, light east
winds prevailed between high pressure over northern Ontario and a
trough from Kansas toward the southern Great Lakes.
Tonight, Models and radar/satellite trends suggest that the snow
will continue increase over Upper Michigan late this afternoon into
this evening supported by deep layer 280k-295k isentropic lift and
850-600 fgen. As the supporting dynamics weaken and lift off to
the northeast the snow should diminish by late this evening.
Models consensus QPF values to around 0.10 inch along with
snow/water ratios in the 15-20/1 support additional snowfall
amounts of an inch or two. This is also consistent with the 1-1.5
g/Kg available in layer of max isentropic ascent. 850 mb temps
around -15C with ese low level winds could bring some LES or lake
enhanced snow into far north central Upper Michigan near Big Bay
into the Keweenaw from KCMX northward. However, any additional
snow amounts should be minimal, an inch or less.
Monday, mid level ridging and subsidence building over the area
should bring mainly dry weather. However, persistent east to ese low
level winds could still generate some light LES over the north into
the Keweenaw. Temps will recover toward seasonal averages with highs
in the lower 20s.
.LONG TERM...(Monday night through Sunday)
Issued at 403 PM EST SUN FEB 10 2019
A shortwave will bring a deepening system into the region Mon night
and Tue, keeping the surface to 850mb low on a track from southern
Lake Michigan through Lake Huron. Models are in good agreement
overall, but the latest CMC-NH run is an outlier as stronger and
farther NW. This results in moderate to heavy snowfall moving in
from the S late Mon night into Tue afternoon. Lighter snow will
linger through the evening, and will then transition to NW wind LES
Tue night into Wed. E to NE winds will enhance snowfall some over
the N-central U.P. and also lead to blowing snow in areas exposed to
those wind directions on Lake Superior and Lake Michigan. Total
snowfall through Tue evening is currently expected to be 6-8" over
all but the Keweenaw Peninsula which has 4-6". Much of that will
fall in around 6 hours or possibly less late Mon night into Tue
afternoon. Amounts may still change some as models have had some
variability over the last couple of runs.
Otherwise not looking at anything significantly impactful in the
rest of the long term. Models are showing a significant winter storm
in the region late in the week, but all are in agreement in keeping
associated precip SE of the CWA.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 549 PM EST SUN FEB 10 2019
Snow spreading northward into Upper Michigan will bring IFR
conditions into this evening at all sites. Conditions will improve
to MVFR later as the light snow moves out. Will go briefly VFR at
IWD at times late tonight and again Mon afternoon.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 403 PM EST SUN FEB 10 2019
A low pres system lifting from the southern Plains to the Great
Lakes region next week may bring a period of east winds of 30 to 35
knots on Tue. Northerly winds into the 30-35 knot range are also
expected Friday. Otherwise, periods of heavy freezing spray are
expected into next week.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
Heavy Freezing Spray Warning until 7 PM EST /6 PM CST/ Monday
for LSZ240>242-263.
Lake Michigan...
None.
&&
$$
SHORT TERM...JLB
LONG TERM...Titus
AVIATION...07
MARINE...JLB
...Update to aviation forecast discussion...
.SHORT TERM...(This evening through Monday Evening)
Issued at 340 PM CST Sun Feb 10 2019
A broad swath of mid level moisture continues to lift northeast over
the southern and central plains this afternoon. Associated with
stout low level moisture in the form of thick stratus, temps have
managed to stay a few degrees cooler, especially over east central
areas where cloud cover has been dense with readings in the upper 30s.
The initial cooler temps in the afternoon has translated into the
evening with the trend from MOS guidance to be colder for lows
than previous forecasts with readings in the upper 20s along the
Interstate 70 corridor and northward. Meanwhile the latest runs of
the HRRR and RAP are at or just above freezing, lending to some
concern for precip type to start off as freezing drizzle initially
after midnight. Expect the low level lift to increase over east
central areas as the sfc low deepens eastward, lifting the warm
front north. Initial drizzle may quickly switch to a mix of
freezing drizzle, sleet, and snow towards sunrise and the morning
rush hour. Given the timing of the precip and impact to the
morning commute, have opted to issue a Winter Weather Advisory for
the light freezing drizzle along the Interstate 70 corridor in
east central Kansas through 15Z. Low visibilities are also a
concern with the drizzle keeping readings between 1 and 3 miles.
If the drizzle onset is slower however, dense fog may become more
likely in east central Kansas underneath light winds and saturated
sfc conditions.
As the precip along and behind the front lifts into far northern
Kansas, temps are progged to warm above freezing with light rain
showers and drizzle expected for much of the CWA. Therefore, the
Advisory plans to expire at 15Z. Further north towards the
Nebraska border, the onset of frozen precip is closer to 12Z.
Winter Weather Advisory goes into effect at this time and
continues through Monday evening. Areas along and north of the
highway 36 border are most likely to see periods of freezing
drizzle mixed with light snow in the afternoon. Current position
of the front and sfc temps near the Nebraska border may allow the
wintry mix to linger longer into the afternoon. As the wave lifts
out Monday evening, mid levels begin to saturate with optimal
forcing for a mix of snow and/or freezing rain. As you head
further south, qpf becomes lighter towards east central areas with
snow and/or freezing drizzle possible through sunrise Tuesday.
Winter Weather Advisory across far northern Kansas was kept Monday
evening with forecast ice accumulations less than two tenths of
an inch. For much of the CWA, a light glaze of ice is possible by
Tuesday morning.
.LONG TERM...(Tuesday through Sunday)
Issued at 340 PM CST Sun Feb 10 2019
Upper ridging builds into the area Tuesday through Thursday with a
quick warmup underneath gusty southerly winds. Warm downslope flow
towards western Kansas with 925 mb temps increasing to around 10C is
a decent signal for mild temps over northeast Kansas with both the
GFS and NAM guidance hinting at upper 50s for highs Wednesday and
Thursday. The next, progressive upper trough moves in Thursday
evening, becoming closed off over southern Nebraska. Models are in
better agreement on the timing and track of the system with there
being a similar consensus of precip starting as rain before
transitioning to snow towards Friday morning. Light accumulations
may be possible, but this will likely change several days out. A few
extended models are hinting at a much weaker short wave trough
coming through over the weekend, otherwise temps are once again
plummeting down into the single digits by Saturday morning with
highs around 30 degrees.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 541 PM CST Sun Feb 10 2019
IFR to MVFR cigs are expected through 05Z with a transition to all
IFR or LIFR for the rest of the period. Main concern will be the
onset of drizzle and fog with ifr vsbys, then a transition to
fzdz as temperatures cool around 10Z, temperatures should warm
above freezing again by 14Z with drizzle and rain expected through
the end of the forecast period.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 3 AM to 9 AM CST Monday for
KSZ021>024-026-036-038>040.
Winter Weather Advisory from 6 AM Monday to midnight CST Monday
night for KSZ008>012-020.
&&
$$
SHORT TERM...Prieto
LONG TERM...Prieto
AVIATION...53