Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/10/18
Area Forecast Discussion
National Weather Service Cheyenne WY
420 PM MST Sun Dec 9 2018
.UPDATE...
Issued at 420 PM MST Sun Dec 9 2018
Please see latest 00z Aviation Discussion
&&
.SHORT TERM...(This evening through Monday)
Issued at 317 PM MST Sun Dec 9 2018
No short term hazards anticipated through the next 36 hours and
cool and tranquil conditions continue. However, a pattern change
Tuesday and into mid-week will offer the next round of snow and
elevated winds for the region and some travel impacts will be
likely during this time frame. See long-term section for more
details on these upcoming hazards.
Latest water vapor and RAP analysis shows a closed H5 low across
the north-central Plains with a shortwave ridge over the western
Rockies Mountain range and digging trough along the west coast.
Being on the subsident side of the H5 low with deep northwest
flow, temperatures are 5 to 8 degrees cooler today than
yesterday. Luckily, warm air advection will occur Monday but not
in time before some chilly overnight lows. Adjusted guidance
downward given current temperatures and dewpoints for Monday lows.
However, temperatures will rebound as full sun is expected Monday.
A nice diurnal swing of 25-30F degrees looks probable with the
west downsloping winds, near full insolation, and WAA.
.LONG TERM...(Tuesday Night through Saturday)
Issued at 212 AM MST Sun Dec 9 2018
Tuesday night and Wednesday night the models are showing a couple
of progressive shortwaves tracking through the region. Both of
these shortwave will cause strong wind speeds to develop along our
wind prone areas of Arlington, Bordeaux and the southern Laramie
Range. Would not be surprised that we may have High Wind Warnings
posted for these areas in later forecasts. The initial shortwave
on Tuesday night does does not appear to have much moisture
associated with it according to the ensembles, but we will need to
keep an eye on the mountains, for this wave may actually try to
squeeze some moisture in that region.
The better shot of more coverage of snowfall will occur on
Wednesday night into Thursday morning as the second shortwave
passes through with a little more moisture depth and decent lift.
The mountains certainly have the best shot of snow, but there is
a chance for some light snow in the plains of Wyoming and
Nebraska. The exception may be near the Cheyenne Ridge where
downslope flow may limit the precipitation. Both of these
timeframes looks to be quite windy, but there appears to be brief
respite from the wind on Friday, before another shortwave dashes
across the northern Rockies on Saturday and causes wind speeds to
crank up again.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 420 PM MST Sun Dec 9 2018
Gusty winds expected to linger across the region for a few more
hours as sunlight wraps up. VFR conditions expected to persist
through the forecast period.
&&
.FIRE WEATHER...
Issued at 317 PM MST Sun Dec 9 2018
Dry conditions will continue through Monday night but light mountain
snow showers are looking more probable for Tuesday and into portions
of the northern High Plains of Wyoming. Next round of more potent
snow showers and overall coverage will be Wednesday night through
Thursday morning across much of the region. Drier pattern will be
in place by Thursday afternoon through the first part of the weekend.
Overall cold temperatures, snow coverage, and elevated humidity values
will keep fire danger low through the next several days.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
UPDATE...WM
SHORT TERM...JSA
LONG TERM...REC
AVIATION...WM
FIRE WEATHER...JSA
Area Forecast Discussion
National Weather Service Duluth MN
523 PM CST Sun Dec 9 2018
.SHORT TERM...(This evening through Monday)
Issued at 306 PM CST Sun Dec 9 2018
The short term period remains quiet with the main concern stratus
and fog development tonight.
Stratus remained along the International Border and Arrowhead this
afternoon but was diminishing. The clouds in the Arrowhead will
likely hang on the longest into this evening. There remains some
uncertainty if stratus will redevelop tonight and the RAP indicates
northwest Wisconsin will have the best chance along with some fog. A
shortwave will move into northwest Minnesota late tonight then
through the region on Monday. Soundings continue to be very dry so
we expect little from this shortwave. We do increase cloud cover
overnight but only to partly cloudy for most areas with a bit more
cloud over northwest Wisconsin. Lows will dip to 5 to 15 for much of
the area.
Any stratus/fog that forms tonight will lift through the day Monday
and highs will rebound into the mid twenties to around thirty.
.LONG TERM...(Monday night through Sunday)
Issued at 306 PM CST Sun Dec 9 2018
Mild temperatures are expected for the long term with highs
trending above average. There is a chance of light snow Wednesday
in northwest Wisconsin and no significant systems are forecast.
A progressive pattern aloft is forecast for the upcoming week
with the subtropical jet well to our south across the southern
CONUS. A weak shortwave trough will move through the region
Wednesday which may provide sufficient lift for a few snow
showers over northwest Wisconsin. With limited moisture
available, think a dusting of snow up to maybe a half-inch is
forecast. Another shortwave trough will cruise eastward through
the region from early Thursday morning through the afternoon.
Another round of light snow showers with the trough. High
pressure then returns Friday and Saturday. Southwest flow aloft
may result in temperatures warmer than the consensus blend for
Saturday. The deterministic ECMWF and GEM forecasts point to
temperatures much above normal for the start of the weekend. Have
remained close to the consensus blend for now with the GFS not
quite as warm.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 521 PM CST Sun Dec 9 2018
VFR predominant under high pressure, but hz/br floating around.
Best chance for any IFR low stratus/fog in NW WI.
&&
.MARINE...
Issued at 306 PM CST Sun Dec 9 2018
Winds aloft have weakened this afternoon and we will allow the
Small Craft Advisory to expire at 4 PM. A weak trough of low
pressure will move through the region Monday and will lead to
stronger flow aloft starting early Monday morning. Warm lake
temperatures will result in convective mixing into the stronger
winds aloft and yield strong southwest winds at the surface near
the Bayfield Peninsula. Conditions may become hazardous to
smaller vessels before sunrise from Port Wing to Bayfield, WI. As
the trough moves away from western Lake Superior Monday night,
wind speeds and waves will subside with quiet conditions expected
thereafter through midweek.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 14 30 12 25 / 0 0 0 0
INL 7 26 7 22 / 0 0 0 0
BRD 9 32 12 28 / 0 0 0 0
HYR 10 29 12 27 / 0 0 0 0
ASX 15 30 17 28 / 0 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&
$$
SHORT TERM...Melde
LONG TERM...Huyck
AVIATION...Wolfe
MARINE...Melde
Area Forecast Discussion
National Weather Service Quad Cities IA IL
901 PM CST Sun Dec 9 2018
.UPDATE...
Issued at 859 PM CST Sun Dec 9 2018
Stratus low to the ground is expanding over far northern Illinois.
Looking at the HRRR trends, and satellite, I have increased cloud
cover and fog potential to "areas" in Illinois, and also
increased clouds to the 30-40% range elsewhere overnight as the
cirrus clouds are opaque enough to hide stars, and thus limit
radiational cooling to a slower rate than expected.
&&
.SYNOPSIS...
Issued at 258 PM CST Sun Dec 9 2018
Earlier low clouds, which blocked the sun for a time across
portions of E IA and far N IL, have largely dissipated leaving
behind sunny skies at mid-afternoon under the influence of high
pressure. Despite the sunshine, temperatures remain below normal
and managed to only recover into the upper 20s to lower 30s due
to such a cold start and weak mixing, and also a period of clouds
in some areas. Dry weather and moderating temperatures are
expected to start the work week, as the region is governed by
low level westerly flow between high pressure sinking into the
Lower Mississippi Valley and low pressure passing across the Great
Lakes.
&&
.SHORT TERM...(This Evening through Monday)
ISSUED AT 258 PM CST Sun Dec 9 2018
Residual moist low levels and weak warm advection will result in
the potential for more low clouds and fog later tonight into
Monday. However, uncertainty exists on extent of both due to the
likely development of southwest winds and attendant weak boundary
layer mixing. Thus lower confidence on min temps, cloud cover,
and fog and whether it will be more of a concern for aviation or
or public. For lows went a bit colder than the blend given the
clear start and light winds, and have readings from the mid teens
to around 10 degrees.
Modest increase in southwest flow should assist deeper mixing and
lead to continued moderation of temps with widespread highs in
the 30s on Monday. In the absence of any extensive fog/low clouds
to start the day some areas could possibly make a run at 40 degrees
along and especially south of I-80.
.LONG TERM...(Monday Night through Sunday)
ISSUED AT 258 PM CST Sun Dec 9 2018
Monday night and Tuesday...Short wave trof dropping into the
northwestern GRT LKS will induce LLVL southwesterly flow acrs the
region and keep sfc temps from dipping below the mid to upper 20s
Monday night. Associated sfc front may hang up along and west of the
CWA on Tue as the next upstream trof slips east of the Rockies and
induces LLVL cyclogenesis on the central plains portion of the
boundary. Although southwesterly sfc winds may decrease as the
boundary nears on Tue, enough of a warm sector draw acrs the CWA to
help boost temps acrs much of the area into the upper 30s to lower
40s for highs. A deeper mix into base of robust inversion aloft to
H925 MB would even support some mid 40s. With such a dry airmass in
place, prefer the slower top-down saturation pace and moisture
advection of the 12z GFS which would keep the area dry through 12z
Wed.
Wednesday...The above mentioned upper level trof shears out acrs
the mid to upper MS RVR Valley this period, with the medium range
models varying in strength and extent of moisture return/column
saturation. The 12z GFS is less pronounced and more progressive, but
doesnt`t break out light precip until late Wed morning and into the
afternoon. Fcst soundings suggest a complex vertical thermal profile
setting up aloft, with evapo-cooling combining with lingering above
freezing layers to make for a possible wintry mix of rain, sleet and
snow. By the time the GFS breaks out precip, most sfc temps besides
maybe the far north should be above freezing and limit freezing rain
potential. The GFS would switch a cold rain or rain-snow mix to all
wet snow in the northeastern third of the DVN CWA from late
afternoon and into the evening, with light snow accums possible
before the precip exits off to the east by mid to late evening. Much
of the rest of the area would be mainly light rain during the day
Wed.
The more developed 12z ECMWF closes off the upper low along and
just south of the DVN CWA, and more robust dynamical cooling aloft
would mean more rain-snow mix or even an earlier switch over to all
wet snow during the day. Some of this would melt diurnally, but the
Euro would still make for some light slushy snow accums of at least
an inch in some areas on grassy/elevated sfc`s. An then there is the
12z NAM, which saturates a LLVL layer of moisture with a dry wedge
lingering aloft as lift increases, setting up a freezing drizzle
scenario for a few hours Wed morning before sfc temps climb above
freezing. With the complexity and the system still several days
away, for now will advertise rain or a rain-snow mix, with some
trends in the north to all wet snow by evening.
Thursday through Sunday...Assessing the latest suite of 12z medium
range model runs, it`s obvious phasing and handling issues continue
with respect to evolution and development of a long wave upper trof
and underlying storm system at the end of the week. The 12z ECMWF
and GEM phase late or don`t totally phase northern and southern
stream upper waves in time to draw the system further northwest and
impact the local area. This while the 12z GFS run is an outlier with
a further north and west phasing that allow a portion of the initial
main precip shield to funnel up along an inverted LLVL trof feature
and make it acrs at least the southeastern half of the fcst area Thu
night with secondary def zone type precip bands rotating acrs the
eastern and southeastern CWA well into Friday. Besides maybe the far
northwestern flank of the precip bands, the GFS`s thermal profiles
suggest mainly rain during this period. A wintry mix may affect the
CWA under the northwest fringe of the precip Thu night, which the
current GFS solution suggests could be right over the MS RVR Valley.
But of course, tough to get wrapped up in the details at this point
with the system still almost 5 days away and model inconsistencies.
But upper jet patterns of the last several model runs make a lean
toward the further south and southeast phasing/storm development
solutions, like the current ECMWF and GEM runs are advertising.
After whatever manages to develop and move acrs the central into
eastern CONUS at weeks end, wake-system upper ridging should bring
about a fair wx Saturday into early Sunday. After that, lower
amplitude progressive pattern may then look to usher acrs some type
of trof again for more precip chances in or near the local area from
late Sunday into next Monday. However, there is low confidence in
adequate moisture return at that time to fuel much of anything.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday Evening)
ISSUED AT 510 PM CST Sun Dec 9 2018
Light southwest winds and a high thin overcast will continue
through the night. The surface conditions remain rather hazy,
which will continue to lead to a likelihood of fog overnight,
with visibilities forecast to drop to 3-4 miles widespread, but
potentially under a mile in more isolated locations tonight. All
fog will slowly lift to near 5-6 mile visibility by mid morning.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...Ervin
SYNOPSIS...McClure
SHORT TERM...McClure
LONG TERM...12
AVIATION...Ervin
Area Forecast Discussion
National Weather Service Hastings NE
502 PM CST Sun Dec 9 2018
.SHORT TERM...(This evening through Monday)
Issued at 325 PM CST Sun Dec 9 2018
No major concerns in the short term with dry conditions expected.
Afternoon satellite analysis shows an upper level disturbance
diving S from SD into NE. Another weaker wave is moving SE through
the Central Rockies. The biggest "eye catcher" is the departing
storm over the Mid-Atlantic. Upper level ridging is situated
across the western CONUS.
Despite the aforementioned system dropping into the area this
evening and overnight, little in the way of sensible wx is
expected due to very dry atmosphere as a whole. About all we will
see are some scattered high clds. NAM continues to be over
aggressive with low clds/fog due to the way it is handling the
ongoing snow cover. However, we are seeing temps near or above
freezing this aftn which is resulting in some melting and winds
are forecast to become lgt overnight. Thus, cant completely rule
out some patchy ground fog late tonight. Left fog mention out of
the official forecast at this time due to low confidence and
limited impacts, if any. HRRR and RAP have been consistent today
in forecasting little to no fog for CWA with better chcs E of the
area. Lows tonight will be quite chilly again and range from
single digits N to mid teens S.
As for temps on Mon, some areas have exceeded expectations today
whereas others are pretty close to previous forecasts. This is
likely due to the non-uniform snow depth across the area as areas
that have warmed up nicely (mainly S/SE CWA) have little to no
snow on the ground. This overall trend is likely to continue next
several days as the snow cover slowly erodes. As such, tried to
reflect this pattern in Mon highs by nudging up GI to Hastings and
points SE and also across KS zones. Mon should be quite similar
to Sun in terms of plentiful sunshine and winds will be lgt, so
overall a nice day.
.LONG TERM...(Monday night through Sunday)
Issued at 325 PM CST Sun Dec 9 2018
Generally quiet conditions expected for much of the week with the
trend toward decreasing pcpn chcs on Thu. Temps will largely be
near-above norm for the balance of the week and into next weekend.
The period starts off with shortwave ridging on Tue before a
weak, fast-moving wave slides through the area within the
zonal/WNW flow Tue night-Wed AM. This system also looks moisture
starved. The latest EC run, much like the previous run, hints at
some lgt QPF for E CWA, but overall this is a low chc. Temps on
Tue will be fairly similar to Mon in the mid 30s to mid 40s from N
to S.
Models are in much better agreement compared to 24hrs ago for the
system on Thu. The Canadian model has trended much closer to the
GFS/EC with good agreement now of a broad, open trough passing
thru with the local CWA in between a northern vort max and a
southern vort max. The southern vort max is forecast to deepen and
close off well S/SE of the area and turn into another potent
system for the E third of CONUS. Given the open and split nature
of the system, locally, agree with latest blend of only low end
pcpn chcs. Of course, there is still time for this forecast to
change, but confidence is increasing that our wx will be fairly
benign for the upcoming week.
Temperatures should be consistently near to above normal this
period. The blend continued the trend from last night in
increasing temps Fri into next weekend. This has support from the
EC ensemble mean as H85 temp anomalies climb from +1-3C on Fri to
+8-10C on Sat. Current forecast calls for highs in the low 40s to
low 50s, and this may still not be warm enough.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Monday)
Issued at 500 PM CST Sun Dec 9 2018
VFR conditions are expected through this TAF period.
Any fog should remain east of the terminals tonight, and only a
few high clouds are expected.
Winds will remain light as they gradually turn westerly to
southwesterly tonight into Monday morning.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
SHORT TERM...Thies
LONG TERM...Thies
AVIATION...Mangels
Area Forecast Discussion...UPDATED
National Weather Service Gray ME
910 PM EST Sun Dec 9 2018
.SYNOPSIS...
Cold but rather quiet weather will continue for much of the
week. A Canadian clipper system with an associated moisture
starved cold front will cross the area Wednesday accompanied by
scattered mainly mountain snow showers. Late week a large ridge
with clear skies will build over the area but move offshore by
late Friday. Over the weekend a storm system moving northeast
from the Gulf of Mexico with bring warmer and wet weather to the
region.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Update...Minor tweaks to temps...as readings S of the cloud
cover continue to fall while they hold steady beneath the
overcast. Also seeing continued signs on radar of upslope snow
showers along and N of the mtns. Satellite difference products
showing two levels to cloud cover in the Nrn zones...so some
seeder-feeder snowfall is possible...and that is where the
higher snowfall totals are located in our forecast.
Previous discussion...Snow showers will begin to press eastward
and into the northern mountains of Maine and New Hampshire
towards sunset. Latest HRRR indicates that light precipitation
will slowly accumulate in this region by 23Z. Outside this
region, partly cloudy conditions can be expect, but still cold
with lows in the teens. Single numbers expected in the mountains
where cold air advection will yield H8 temperatures near -16C
by late tonight.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
Dry and mainly clear conditions expected for Monday and Monday
night as a weak and narrow ridge of high pressure crests over
the region from Canada. Nearly full sunshine will allow for
readings to push the freezing mark over southern areas during
the day Monday.
With continuing mainly clear skies and light winds Monday night,
expect radiational cooling to dominate the region. This will
allow temperatures to fall to near zero in northern areas by
late at night. There may be some cloudiness entering far western
areas by dawn from the west as a weak area of low pressure, a
clipper type system, approaches from the Great Lakes region.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
A Canadian clipper system with very limited moisture will move
through the northeast Tue night and Wed bringing scattered snow
showers mainly to the mountains. Behind the clipper another
shot of very cold air moves across the region late Wed into Wed
night with some gusty winds. By thu the high becomes centered
over the region with sunny crisp skies and calm winds. Fri the
high moves offshore allowing increasing mid/high WAA clouds from
the southwest. On Sat the system traveling along the Gulf of
Mexico states gets kicked to the northeast and approaches the
area with a strong waa pattern in advance. Rain is expected to
overspread the region Sat but may start as a mix in the mtns.
Models are all over the place with the system for the weekend
so some hedging will be involved.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
Short Term...Mainly VFR conditions outside the mountains. Low
clouds and snow showers expected across the high terrain.
Long Term...Mainly VFR conditions.
&&
.MARINE...
Short Term...SCAs will remain in place for all areas tonight
outside Casco Bay. Winds to switch from the southwest to
northwest after the passage of a cold fropa tonight with gusty
winds expected.
Long Term...No flags. SCA conds may occur over the outer waters
late Wed into Wed evng.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...Small Craft Advisory until 6 AM EST Monday for ANZ150>152-154.
&&
$$
NEAR TERM...Legro
Area Forecast Discussion
National Weather Service Marquette MI
646 PM EST Sun Dec 9 2018
.SHORT TERM...(This evening through Monday)
Issued at 257 PM EST SUN DEC 9 2018
WV imagery and RAP analysis indicated northwest mid/upper flow
through the northern Great Lakes on the periphery of a trough
through northern Quebec. At the surface, westerly flow prevailed
between a ridge from the central plains into WI and low pressure
over northern Quebec. Visible Satellite loop showed lingering low
clouds through the Keweenaw and eastern Upper Michigan with clear
skies over the rest of the area. The clouds were supported by lake
moisture and shallow cold air.
Tonight, persistent wnw low level flow will maintain the lower
clouds over the Keweenaw and eastern Upper Michigan. With 925-900mb
temps to around -7C and moisture depth also to around 2k ft mainly
just trace pcpn if any is expected. Scarce ice nuclei would also
support mainly fzdz/flurries if pcpn develops. Backing winds
overnight should also move the clouds/pcpn out of much of the east.
Over the rest of the area, radiational cooling will be strong enough
even with wsw winds overnight for temps to drop to near 10F.
Monday, wsw winds will favor any lingering pcpn for the nrn
Keweenaw. Otherwise, sunshine will help boost temps into the upper
20s to around 30.
.LONG TERM...(Monday night through Sunday)
Issued at 343 PM EST SUN DEC 9 2018
For the bulk of the extended periods, it will feature a rather
benign pattern. A weak upper level shortwave will pass overhead Mon
ngt, with some weak moisture expected for the eastern portions of
the forecast area. POP chances are rather low; however, the concern
is more with the p-type. The lower levels of the atmosphere indicate
the lack of a lift component, indicating that any moisture that does
arrive will be more of a drizzle or small droplets. Unfortunately
surface temps will likely be sub-freezing, so the concern resides
with freezing drizzle Mon ngt/Early Tue before the system departs to
the east.
Then as advertised, mid-level heights begin to rise Tue upstream
with surface ridging progged to return and provide dry conditions
for Tue-Wed. Before focusing on yet another shortwave progged to
arrive from the southwest Wed ngt.
Mid-level ridging remains through midday Wed as the vort max
continues to inch northeast towards the Great Lakes region. Low-
level moisture flow will be from the southeast helping with some
better isentropic ascent; however, some dry air remains in the mid-
levels and aloft, which could produce a similar issue with freezing
drizzle or remain as a rain/snow mix later in the week. At this time
guidance indicates precip type will start as snow before a light
wintry mix develops.
This system will then pass to the east, with a return to ridging and
quiet weather later in the week. Temps throughout the extended
periods will hover in the upper 20s to mid 30s for highs, and
overnight lows will fluctuate depending on cloud cover from the
teens to 20s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 643 PM EST SUN DEC 9 2018
VFR conditions are expected to prevail at KIWD and KSAW through the
forecast period. Westerly winds off of Lake Superior along with
shallow cold air will maintain low cigs at KCMX with low-end MVFR
conditions and some patchy fzdz possible tonight. Cigs will
gradually improve during the day on Monday reaching VFR by mid to
late afternoon.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 257 PM EST SUN DEC 9 2018
Sustained winds will remain to around 20 knots into tonight. By
Monday, the winds will become sw in the 20-30 knot range over the
west. Locally higher gusts will be possible near the west side of
the Keweenaw where land breeze convergence is expected. Winds will
then diminish Monday night. Relatively benign conditions will
then take over through early Wednesday, with winds picking back up
for the latter half of the week.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JLB
LONG TERM...Beachler
AVIATION...Voss
MARINE...JLB
Area Forecast Discussion
National Weather Service Shreveport LA
947 PM CST Sun Dec 9 2018
.SHORT TERM.../Tonight/
The back edge of the cu field continues to rapidly diminish from
N to S across Lower E TX/N LA this evening, as much drier air is
advecting S in wake of the upper trough passage which has shifted
into NE MS/NW AL. However, the RGB channel on the satellite
imagery, as well as sfc obs from MLU and BQP indicate that patchy
dense FG has developed over Ern Union/Nrn Ouachita Parishes this
evening, although LA DOTD traffic cameras along I-20 in E MLU
still indicate good vsbys attm. The last few runs of the HRRR have
depicted dense FG development over the far Ern sections of Ncntrl
LA tonight, and given the calm winds/clearing sky/very wet soils,
believe that patchy FG will spread farther S across the far Ern
sections of the region overnight. Even though satellite imagery
also depicts a cirrus shield beginning to increase along the next
shortwave trough axis over Ern OK ahead of a closed low diving SE
across Wrn KS/NW OK attm, do not think this will deter FG
development here as these elevated cigs will move in late.
Have added patchy dense FG wording to these areas tonight, but
with temps falling to/below freezing late, this FG may become FZFG
and may deposit a thin coat of ice on elevated objects such as
bridges and overpasses. Will allow the mid shift to continue to
monitor trends overnight, but will not issue a Dense FG or FZFG
Advisory attm given its localized nature. Also cleaned up the sky
trends to match the latest obs, with a few minor upward tweaks to
min temps given the recent trends and winds expected to keep the
air mixed enough over much of the region and keep temps from
falling much below freezing. Otherwise, the remainder of the
forecast is in good shape.
Zone update already out...grids will be available shortly.
15
&&
.PREV DISCUSSION... /issued 559 PM CST Sun Dec 9 2018/
AVIATION...
The back edge of the MVFR cigs have reached a DKR, to RFI, to just
S of SHV, to MNE and BQP line as of 00Z, with VFR cigs expected to
return at LFK and MLU by mid-evening. Still seeing some 10kft
cigs across SW AR/extreme Nrn LA just behind the MVFR cigs, but
these will quickly diminish across N LA by mid to late evening. An
upper level shortwave trough entering the Upper Red River Valley
of SW OK will result in an increasing cirrus shield across Srn
OK/N TX this evening, eventually spreading across much of the
region after 06Z Monday. This will quickly diminish from W to E
between 10-15Z, with SKC expected for the remainder of the 00Z TAF
period. NW winds 5kts or less tonight will range from 5-7kts
after 15Z Monday. /15/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 32 51 29 58 / 0 0 0 0
MLU 30 50 25 56 / 0 0 0 0
DEQ 24 51 24 57 / 0 0 0 0
TXK 29 50 27 56 / 0 0 0 0
ELD 27 49 24 55 / 0 0 0 0
TYR 31 53 33 58 / 0 0 0 0
GGG 31 52 30 59 / 0 0 0 0
LFK 33 55 29 58 / 0 0 0 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
15