Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/29/19
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
544 PM CST Thu Nov 28 2019
...00z Aviation Update...
.DISCUSSION...Updated for latest aviation discussion below.
&&
.AVIATION...MVFR ceilings will drop into the IFR range later this
evening and overnight. As ceilings drop, some visibility
reductions can also be expected. Also, can`t rule out some light
drizzle or shower activity, but this will be spotty at best.
Shortly after sunrise on Friday, ceilings will begin to improve
slightly back to MVFR ranges. Southerly winds will also begin to
increase with some gusts exceeding 20 knots in the afternoon.
&&
.PREV DISCUSSION... /issued 231 PM CST Thu Nov 28 2019/
SHORT TERM (Now through Friday Night): Coastal low pressure has
weakened the pressure gradient and allowed winds to become light
and northwesterly this afternoon. Overcast skies dominate and
have kept temperatures stifled, with most locations in the valley
near 70 degrees and likely not reaching too much higher through
the next hour or so. Conversely, reinforcing moisture,
southeasterly flow, and thicker low level overcast arriving this
evening will likely keep temperatures up this evening and tonight.
Models continue to show south to north moving light showers
developing this evening and continuing on and off through Friday
morning.
The HRRR has been handling the placement of offshore showers
pretty well through the morning. Leaning more HRRR and NBM through
the night with PoPs generally 20 to 30 percent along the coast
into the mid and upper RGV. With the increasing low level moisture
and lighter winds, have continued patchy fog wording into the
valley with areas of fog possible across portions of the northern
ranchlands. Front heads north tomorrow as a warm front, kicking
the coastal low further north and dragging the chance of rain with
it. Optimistically kept highs on Friday nudging into the low 80s
for most locations with slowly improving sky cover into Friday
night.
Observed water levels are running roughly 0.8 of a foot above
predicted astronomical tides this afternoon, with a high tide of
just under half a foot expected at 7 28 PM. Will go ahead and
issue a Coastal Flood Statement for water levels reaching above 1
foot MSL.
LONG TERM (Saturday through Thursday): Few changes were needed to
the inherited forecast. Models were in fair to good agreement
leading to good forecast confidence. A storm system moving out into
the Plains Saturday will open the door for a cP air mass to move
south from Western Canada and across the Four Corners into West
Texas. This will set up a weak front that will move slowly into
South Texas, not pushing into deep South Texas and the RGV until
Saturday night and Sunday morning. The front will run into high
pressure over the Gulf and may set up a weak coastal trough Sunday
morning, enough to briefly enhance north to northeast winds and
bring a few showers to the area as the front moves through. High
temperatures well into the 80s to near 90 on Saturday will be doused
down to near normal, in the mid 70s, on Sunday. The front will have
enough momentum to push offshore Sunday into Monday, and mid level
ridging and high pressure will settle over the area. A progressive
mid level pattern will continue into next week, with deeper systems
avoiding South Texas. A weak front, of lower latitude trajectory,
will interact with return flow on Wednesday, setting up coastal
showers, but return flow will set up again within 24 hours. A
stronger front with Canadian cP air will be headed south toward the
RGV for arrival on Friday.
MARINE:
Now through Friday Night: Coastal low pressure has kept winds
lighter today, allowing seas to slowly subside. ESE swell has
continued to near 5 feet at offshore buoys. The frontal boundary
lifts north and pushes the coastal low with it tomorrow, bringing
moderate southeasterly flow back across coastal waters. Seas
respond to 3 to 5 feet by Friday afternoon and build to Small
Craft Caution conditions Friday night. Chance of rain increases
slightly tonight into early Friday, with no convection expected at
this time.
Saturday through Tuesday night: Less than favorable marine
conditions due to elevated wave heights will persist from Friday
night into Saturday. Small craft advisory conditions may be in
effect over the Gulf waters. Some improvement will be possible
Saturday night, but winds will shift to northeast on Sunday as a
weak front pushes through the area, which will also prolong or
rebuild higher seas. Improved conditions will eventually return on
Tuesday as high pressure spreads over the northwest Gulf and
subsequently shifts east.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
This product is also available on the web at:
HTTP://WEATHER.GOV/RGV
Aviation Update...Frye-55
Area Forecast Discussion
National Weather Service Cheyenne WY
537 PM MST Thu Nov 28 2019
.UPDATE...
Issued at 534 PM MST Thu Nov 28 2019
Updated forecast for tonight to include some freezing drizzle
across the southern Nebraska panhandle, with some reports of
freezing drizzle just to the east of Sidney in the last hour.
Expect fog to become more widespread and a bit more dense across
the eastern plains (along and east of Interstate 25) tonight. May
need a Dense Fog Advisory for portions of the area, especially if
surface winds become a little more easterly. For now, will hold
off since only a few areas show visibility of 1/4 to 1/2 mile at
this time.
UPDATE Issued at 435 PM MST Thu Nov 28 2019
...Please see latest 0Z aviation discussion...
&&
.SHORT TERM...(This evening through Friday)
Issued at 244 PM MST Thu Nov 28 2019
A low level inversion will keep the stagnant moisture near the
surface. This will aid in fog staying present in several locations
this afternoon and through early morning. Winds are not expected
to increase or aid with mixing low level temperatures with the
atmosphere.
The focus turns toward the stacked upper level low over the
California coastline, late Thursday into Friday. Due to quickly
developing strong atmospheric dynamics aloft, a surface low will
form on the lee side of the mountains in Colorado adjacent to the
dissipating surface low over California/Arizona. What is going to be
impressive with the development of this surface low is how quickly
it will occur. Between 12Z Friday the GFS has the surface low center
near Pueblo at 1007mb. Within 24 hours, the surface low will deepen
to a 980mb weather system centered near the SD/NE state line. This
is a very good example of cyclogenesis turning the needle to the
classification of bombogenesis due the extremely rapid development.
Associated with this rapid development will be the very strong
winds. By Friday afternoon winds will begin to intensify, especially
to the east of the Laramie Range. Precipitation will start off as
snow in the higher terrain by Friday morning and fill in to lower
elevations on the western edges of the CWA as the weather system
develops over Colorado and propagates toward the Northeast.
.LONG TERM...(Friday night through Thursday)
Issued at 244 PM MST Thu Nov 28 2019
...POWERFUL WINTER STORM COULD BRING BLIZZARD CONDITIONS TO
WESTERN AND NORTHERN PORTIONS OF THE CWA THIS WEEKEND...
Recent RAP analysis shows a 150+ kt 250 mb jet in the process of
rounding the base of the longwave trough along the Pacific Coast.
This upper level trough will mature and begin a significant push
east into the Great Basin over the next 24 hours which will support
lee cyclogenesis over northeastern Colorado. Numerous models
suggest a 992 mb SFC low developing which will help to draw up
gulf moisture for this next system. Precipitation will begin to
spread across the CWA Friday night as the SFC low pulls off toward
the north. Soundings suggest rain and freezing rain may initially
fall for the NE Panhandle before transitioning to all snow by 06z
Saturday. A warm layer around 750 mb is present before quickly
cooling off with the approaching trough. Only a light glaze of
ice accumulation is expected.
Heading into overnight Friday and early Saturday, the heaviest
snowfall will be expected across northern portions of the CWA and
winds will begin to increase. The low center looks to stall around
the NE/SD border increasing the residence time of the TROWAL over
Converse and Niobrara Counties in Wyoming and Sioux and Dawes
Counties in Nebraska. Latest SREF guidance shows over 50% of
members with a dendritic growth zone deeper than 50 mb over these
areas from 12z Saturday through 03z Sunday. Therefore, will most
likely see higher snowfall totals across these zones with 6 to 10
inches likely. To the west, northerly upslope flow and moisture
rich air will support the mountains reaching snow totals over 1
foot. Currently have snow in the mountains beginning before the
00z start time of the watch so may need to bump up the headline
timing if upgraded in subsequent updates. Looking farther
southeast towards Cheyenne and Sidney, only 1-2 inches are
expected as most of the moisture will remain to the north.
However, another hazard will be in play for these zones.
Strong wind gusts are expected on the back side of the low as the
descending cold conveyor belt wraps around and downslope flow
helps to accelerate these winds down to the surface. 12z GFS
forecasts 80 kts at 700 mb over Cheyenne and 70 kts at 800 mb over
the NE Panhandle by 12z Saturday. Recent model runs have slightly
shifted the 700 mb low south which would push the strongest winds
south of the CO/WY border so will need to monitor future model
runs. Regardless, widespread wind gusts in excess of 65 MPH can
be expected over much of eastern Wyoming and western Nebraska.
Area soundings from the NAM show SFC winds around 30-40 kts which
would already be at or near High Wind criteria. These strong winds
will not only be hazardous to travelers by itself, but will
create significant blowing snow across the region with new
snowfall and if snow crust can be blown off of the existing
snowpack from the early week storm. Numerous forecast zones that
could be under a High Wind Watch are under a Winter Storm Watch
for the threat of blowing snow causing blizzard conditions and
significant impacts to travelers.
Looking at Sunday and beyond, zonal flow takes over for the most
part aloft with weak ridging and troughing through the week.
Afternoon temperatures will return to near normal in the low 40s
east of the Laramie Range and 30s west. Next chance of precipitation
will be a progressive shortwave moving through Colorado on Thursday.
CPC`s 6-10 day outlook suggests normal to slightly above normal
temperatures and slightly above normal precipitation heading into
next weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 435 PM MST Thu Nov 28 2019
Flight conditions remain poor for tonight and tomorrow.
Widespread moisture and cloud cover are keeping many sites at IFR
and LIFR. Conditions will hold steady overnight tonight and
little improvement is expected even throughout the day tomorrow as
the next system approaches. By tomorrow evening, snow showers
will develop west and spread east and keep visibility and
ceilings at LIFR.
&&
.FIRE WEATHER...
Issued at 330 AM MST Thu Nov 28 2019
No fire weather concerns w/ deep snow pack in place for all
areas.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Winter Storm Watch from Friday evening through late Saturday
night for WYZ101>110-113-116.
High Wind Watch from Friday evening through late Saturday night
for WYZ115-117>119.
Winter Storm Watch from Friday evening through late Saturday
night for WYZ112-114.
NE...Winter Storm Watch from Friday evening through late Saturday
night for NEZ002-003-095-096.
High Wind Watch from Friday evening through late Saturday night
for NEZ019>021-054-055.
&&
$$
UPDATE...TJT
SHORT TERM...BW
LONG TERM...MB
AVIATION...CW
FIRE WEATHER...CLH
Area Forecast Discussion
National Weather Service Quad Cities IA IL
516 PM CST Thu Nov 28 2019
...00Z AVIATION UPDATE...
.SYNOPSIS...
Issued at 300 PM CST Thu Nov 28 2019
It`s been a cloudy Thanksgiving Day across the region thus far;
all due to a layer of dry air above 850 mb trapping moisture in
the low levels of the atmosphere. Temperatures have struggled to
really climb today, and as of 2 PM were in the lower 30s across
the area. Further west, infrared satellite showed clouds
increasing with strengthening WAA across the central and eastern
Great Plains. This was all ahead of a deep 500 mb trough centered
across the Pacific Coast, which will be our primary concern for
the short term period.
&&
.SHORT TERM...(This Evening through Friday)
ISSUED AT 300 PM CST Thu Nov 28 2019
Key Messages:
1) Precipitation to gradually increase in coverage late tonight.
2) Freezing drizzle possible west of the Mississippi Friday morning,
changing to all rain by mid-morning.
3) Rain and a slight chance of thunder Friday Night
As the evening progresses, the 500 mb trough will strengthen and
become more negatively tilted as it progresses towards the Rockies.
As it does so, the southern flank and associated CVA will race
towards Colorado, allowing for the development of a surface low by
late Friday in the western Plains.
While this is all going on, southerly flow aloft will gradually
strengthen over the Great Plains and westernmost Midwest, leading to
increasing low-level WAA. Precipitation will form under this WAA
wing and some ripples of passing CVA at 500 mb beginning late this
evening and tonight, which will try and work its way into our area.
The trouble is, as is with similar situations, is how the very dry
air aloft impacts initial onset.
As mentioned in the previous discussion, CAMs remain relatively
mixed on the onset. The NAMnest is the most aggressive solution,
which shows an area of drizzle to light rain showers moving into the
area after midnight. The HRRR is less aggressive overall, and shows a
slower progression of drizzle from west to east after midnight
through Friday morning. This falls more in line with global guidance
like the GFS and CMC, and so have trended more in this direction.
The ultimate question remains whether we can become saturated or
not. As a result, only have QPF values of a few hundreths or less in
the current fcst through the morning.
With cold air (temperatures below freezing) still in the low levels
due to the overlying stratus, there is potential for areas of
freezing drizzle during the morning, especially for areas west of
the Mississippi. This could lead to potential for some slippery
condtions on roads and sidewalks before temperatures slowly warm.
After collaboration with neighboring offices, have decided to hold
off on an advisory for now due to low confidence on the saturating
of the atmosphere for drizzle, and will pass concerns along to the
evening shift for further evaluation.
By mid morning, forecast soundings show temperatures will warm above
freezing in the vertical, allowing precipitation to change to all
rain. This will remain the case through Friday night, as winds
increase out of the southeast and low-level WAA,isentropic upglide
strengthens further. A second round of rain, with a slight potential
for a thunderstorm, will arrive Friday evening and overnight.
Rainfall amounts during this time will range from a quarter to
slightly over half an inch, with the heaviest amounts expected south
of Interstate 80.
The impacts from the storm will continue into the early portion of
the long term period.
.LONG TERM...(Friday Night through Thursday)
ISSUED AT 300 PM CST Thu Nov 28 2019
Main Points:
*Next storm system to bring widespread rain and a few
thunderstorms Friday afternoon through Saturday.
*Chance of light snow or snow showers under the closed upper low
Saturday night and Sunday. Minor accumulations are possible,
favored in the north and west. Low confidence on the details.
*Quiet weather returns for much of next week with near to
slightly below normal temperatures for early December.
Friday Night and Saturday
Significant theta-e advection, downstream of a deep closed 500mb
low over the central Plains, and upper divergence from curvature
in the flow will lead to widespread light to moderate rain across
the CWA. Elevated weak instability could support embedded
thunder/isolated brief storms as well.
The steadiest rain will fall Friday night into early Saturday
morning before the upper low`s dry slot begins to punch into
eastern Iowa and northwest Illinois. Chances for rain will
continue through Saturday afternoon, but overall won`t be as
widespread and will be on the light side. For total QPF amounts,
model consensus has a range from 0.35 to 0.75 inches. Higher
totals near 1 inch are possible which the ECMWF and GFS have
across the southern tier or two of counties.
Highs on Saturday are a little tricky with bias corrected models on
the warm side of the distribution and raw guidance 5-8 F colder.
Trended temps to just under the 50th percentile due to effects
from thick cloud cover, widespread rain, and SE surface winds as
opposed to south or southwest. Still looking at a large north to
south temp gradient with low to mid 40s north and mid or upper 50s
far soutwest.
Saturday Night and Sunday
The occluded surface low, and tightly wound up upper low, will
slowly track across the Upper Mississippi Valley into Sunday. Model
consensus takes a 990-995mb low near the Wisconsin/Illinois border
into southern Michigan during this time. Once the low passes east
of our area, cold air advection aloft and decreasing thicknesses
should cool the vertical thermal profile enough for precip type to
transition from rain to snow in the deformation zone. By the time
this occurs, the low will have lost a lot of its punch with the
warm moist conveyor already aimed into the East Coast, largely
cut off from backside of the low. Thus, additional QPF amounts
will be light.
If surface wet-bulb temps cool enough we could get some light snow
accumulation, favored north and west across the CWA. Many
locations will probably not receive measurable snow. However,
there is potential for convective like snow showers as model
soundings are showing low MUCAPE, which would be accompanied by
gusty NW winds (possibly 30-35 mph). This combination could lead
to some travel impacts, at the very least from visibility
restrictions. Still have low confidence on the details, but
something for later shifts to reassess.
Forecast highs on Sunday are in the mid/upper 30s in the NW
corner to upper 30s or low 40s elsewhere. Uttech
Next week
A quiet and dry period with near normal temperatures as our
area will be in a northwest flow aloft. Highs in the upper 30s to
mid 40s should be common.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday Evening)
ISSUED AT 515 PM CST Thu Nov 28 2019
A gap in the low clouds will produce a brief period of VFR
conditions early this evening at CID, MLI and BRL. Otherwise, MVFR
conditions due to ceilings from 1500 to 2000 agl and light
easterly winds will remain in place overnight. Some light
precipitation, in the form of rain, snow or sleet may impact the
BRL area early. Elsewhere, very light mixed precipitation will be
possible overnight into Friday, but forecast confidence is too low
to include in the forecasts at this time. As a system approaches
from the plains, ceilings are expected to lower during the day
with IFR conditions most likely at CID and DBQ.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...Speck
SHORT TERM...Speck
LONG TERM...Uttech/Haase
AVIATION...Sheets
Area Forecast Discussion
National Weather Service Hastings NE
504 PM CST Thu Nov 28 2019
.SHORT TERM...(This evening through Friday)
Issued at 315 PM CST Thu Nov 28 2019
Aloft: Highly-amplified SW flow was over the Cntrl Plns. WV
imagery...aircraft winds and RAP tropopause analyses showed a
subtropical high over the GlfMex with a deep -5 SD low along the
CA coast. A wk shrtwv trof has been crossing Cntrl Plns today and
it was over NEB and heading NE. SW flow will remain over the rgn
thru Fri. The CA low will move inland with a potent shrtwv trof
rotating around its Srn periphery. This trof will be over CO by
00Z/Sat with the LFQ of a 120 kt jet streak overtaking the Cntrl
Plns.
Surface: Strong 1041 mb high pres was over MB and extended S to
the GlfMex. Low pres will be advancing thru and organizing over
the Wrn USA...with lee cyclogenesis over CO Fri afternoon.
As the shrtwv trof is departing the rgn...the deep mstr is
exiting with it leaving just low-lvl stratus. The -SN has been
very stubborn to end...but the UEX VWP does show lowering cldtops
and we`ve seen the -FZDZ at ODX and received a rep of -FZDZ in
Jewell co. Persistent low-lvl WAA will cont thru tonight...and
strengthen tomorrow as low-lvl winds incrs.
Rest of this aftn: Cldy with any lingering -SN ending. Patchy
-FZDZ will remain psbl. Confidence is occurrence is medium given
the fcst depth of the stratus (as high as 10K ft).
However...confidence in coverage and severity is low.
Would prefer to have a warm front aprchg from the S for higher
confidence (better ascent).
Tonight: Cldy. Patchy -FZDZ...but temps will slowly rise espcly
after 03Z and that will chg any FZDZ to DZ. As stated in the prvs
paragraph...overall confidence is medium due to pattern
recognition...but confidence in coverage and severity. The depth
of the low stratus gradually dcrses overnight. That could lower
the potential for FZDZ/DZ after 06Z.
No chgs to Winter Wx Advisory...but it may not verify everywhere.
Best chance of verifying will be over S-cntrl NEB. The Srn part
of this advy (N-cntrl KS) may be cancelled later this evening as
temps rise abv frzg.
Fri: Cldy. Slight chance of -DZ in the morning. The stratus will
probably be too shallow to support it though. After 18Z...incrsg
low-lvl mstr will lead to elevated instability above 800 mb.
MUCAPE could be as high as 500 J/kg. Intensifying WAA should lead
to sct shwrs/tstms.
Uncertainty on high temps...but sided with the cooler guidance as
low stratus will remain locked-in over the CWA.
.LONG TERM...(Friday night through Thursday)
Issued at 315 PM CST Thu Nov 28 2019
Aloft: The Wrn USA low will reform over CO Fri night and then
acrs Wrn NEB Fri night and Nrn NEB Sat. This low will head into IN
Sat. Lower amplitude flow will prevail over the CONUS next wk
with WNW flow over the Cntrl Plns.
Surface: 992 mb low pres over CO will head NE acrs the NEB
Sandhills Fri night and deepen to near 987 mb. The occluded front
will cross the CWA from 06Z-12Z. This low will occlude further
Sat...tightening the pres grad. It will then head into the GtLks
Sun. Quieter wx will prevail the rest of next wk. A sfc trof will
cross the CWA Tue...followed by a wk cool front Wed. Uncertainty
then incrses beginning Thu due to a Srn stream trof fcst to move
thru.
The wind Sat-Sun will be the biggest concern. Replaced NBM winds
with CONSMOS...and fcst wind speeds may still not be enough. The
GFS conts the strongest with wind fields with 50 kt as low as 1000
ft AGL and 60 kt at 850 mb. Given the strong agreement with the
EC (which has a core of 50-55 kt winds) crossing the entire CWA
Sat night...confidence was high enough to issue a High Wind Watch
for most of the CWA (along and W of a line from PHG-AUH-OLU).
Believe it is a virtual certainty the watch will need to be
expanded to include the entire CWA. We still have 48 hrs before
the winds really incrs. That will allow for re-evaluation by
future shifts and mdl runs.
Temps: Overall temps will average at or a little abv normal.
Sunday will be the coldest day with highs in the 30s over most of
S-cntrl NEB.
Precip: Sct shwrs Fri eve. Can`t rule out a little wraparound
light rain/snow Sat into Sat night over S-cntrl NEB...but amts
should be negligible. The features later in the wk should all move
thru dry.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday)
Issued at 504 PM CST Thu Nov 28 2019
IFR ceilings and VIS are expected for the TAF period. Conditions
do not look to improve until tomorrow evening when a cold front
moves through. OCNL -FZDZ looks possible until temps rise above
freezing around 6z. VIS may not improve much tomorrow as warm rain
will mix with the cold ground and BR/FG will linger at the TAF
sites.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...Winter Weather Advisory until 6 AM CST Friday for NEZ039>041-
046>049-060>064-072>077-082>087.
High Wind Watch from Saturday afternoon through late Saturday
night for NEZ039>041-046>048-060>063-072>076-082>085.
KS...Winter Weather Advisory until 6 AM CST Friday for KSZ005>007-
017>019.
High Wind Watch from Saturday afternoon through late Saturday
night for KSZ005-006-017.
&&
$$
SHORT TERM...Kelley
LONG TERM...Kelley
AVIATION...Beda
Area Forecast Discussion
National Weather Service North Platte NE
647 PM CST Thu Nov 28 2019
.UPDATE...
Issued at 639 PM CST Thu Nov 28 2019
After conversing with NDOR and Cooperative observers, freezing
drizzle was being reported in Deuel, Garden, Hooker and Grant
counties. Decided to add these counties to the winter weather
advisory for tonight. Looking at the latest HRRR and NAM12 visby
products, there is a high potential for fog and freezing drizzle
overnight in these areas. With temps expected to hover just below
the freezing mark tonight, the combination of light freezing
drizzle and freezing fog may lead to slick roadways tonight.
&&
.SHORT TERM...(This evening through Friday night)
Issued at 318 PM CST Thu Nov 28 2019
Tonight, continued chances for light freezing drizzle. Much drier
air present above 800mb, to limit any chances for light snow. Ice
accumulations are expected to be light mainly a light glaze up to
a tenth of an inch east of North Platte through Ainsworth. Lows
in the upper 20s. An additional concern will be increasing fog
development across the eastern Panhandle and southwest Nebraska.
Visibilities below a mile are expected, which will also affect
travel.
On Friday, areas of freezing drizzle and fog to continue across
southwestern areas with fog also expected to spread into portions
of central and north central Nebraska thorugh late morning. As
temperatures warm, a transition to drizzle expected by late
morning.
The base of a deep upper trough across the Great Basin will
rotate across the Four Corners Region on Friday as upper ridging
builds into the Northern Plains in response. The upper flow will
become more southerly as the day progresses. This will bring
increasing chances for light rain during the afternoon. 850mb
temperatures contrast between the GFS and NAM from 2-4C GFS, but
only 0 to -3C NAM. Sided with the colder NAM and ECMWF for highs
in the upper 30s to near 40. Winds southeast at 15 to 25 mph
should aid in melting existing snow cover however.
On Friday night, strong height falls across western Nebraska will
develop a closed upper low from the panhandle into northern
Nebraska Friday night. Rain in the evening will spread north and
become widespread across north central Nebraska. Rain should
transition to snow across the northwest sandhills after midnight.
The northwest Sandhills could receive up to 2 inches after
midnight. Strong northwest winds are not expected to arrive so
blowing snow looks limited across the northwest.
.LONG TERM...(Saturday through Thursday)
Issued at 318 PM CST Thu Nov 28 2019
The upper level low tracks from Cherry County early Saturday
morning into far southeast South Dakota and northeast Nebraska by
late Saturday afternoon High winds will develop from the Panhandle
into western and southwest Nebraska. Northwest winds of 30 to 40
mph with gusts to 60 mph are expected. with 700mb winds approach
70kts, a few gusts to 70 mph area also possible. The timing of
highest winds will be from mid morning through late evening. A
high wind watch remains in effect.
Meanwhile, heavy snowfall with blizzard conditions possible are
expected to develop across the northwest Sandhills into northern
Nebraska on Saturday and continue Saturday night. The southward
extent of snow has come into better agreement with the latest
models. One main difference is the GFS remains the warmest model
wrapping warmer H850 temperatures into the eastern half of north
central Nebraska. Again favoring the colder ECMWF and NAM for a
quicker transition to snow from west to east. There could also be
a brief period of freezing rain across north central Nebraska
Friday night into Saturday morning as the system moves east.
Have continued the Winter Storm Watch for Sheridan, Cherry and
Keya Paha County. These areas are expected to receive 6 inches or
greater. The highest amounts near 10 inches expected to be in
northern Sheridan and northwest Cherry County. Light snow
accumulations up to a half inch could extend as far south as I80.
Very windy conditions continue Saturday night.
Conditions should improve Sunday as the system moves into the
southern Great Lakes/Midwest. Still expecting windy conditions
with wraparound snow showers possible eastern portions of north
central Nebraska. Highs only near 30 north to the mid 30s south.
Northwest winds 20 to 20 mph with gusts to 40 mph should diminish
to 15 to 30 mph in the afternoon.
Dry conditions with highs in the 40s to near 50 are expected
Monday through Thursday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 532 PM CST Thu Nov 28 2019
Low stratus continues to push in from the south-southeast with
generally IFR ceilings across the area. Conditions will continue
to deteriorate through the evening as areas of dense fog develop
across much of the local area limiting visibilities to less than 1
mile, impacting LBF/OGA/IML and possibly BBW with LIFR conditions.
With subfreezing temperatures, freezing drizzle will be possible
at these sites through early Friday morning. Expect improving
visibilities by midday Friday but at best IFR ceilings through the
end of the TAF period.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 6 AM CST /5 AM MST/ Friday for
NEZ006>010-022>029-035>038-056>059-069>071.
High Wind Watch from Saturday morning through late Saturday
night for NEZ022>026-035>038-056>059-069>071.
Winter Storm Watch from Friday evening through late Saturday
night for NEZ004-005-094.
Winter Storm Watch from Saturday morning through late Saturday
night for NEZ006.
&&
$$
UPDATE...Buttler
SHORT TERM...Roberg
LONG TERM...Roberg
AVIATION...Jurgensen