Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/13/18
Area Forecast Discussion
National Weather Service Cheyenne WY
403 PM MST Wed Dec 12 2018
.SHORT TERM...(This evening through Friday night)
Issued at 230 PM MST Wed Dec 12 2018
Forecast challenges deal with ongoing high winds today and
possibility of snow squalls as a front moves through the area
late this afternoon into the evening hours. Strong winds possible
again Thursday.
Currently...Surface analysis showing a strong cold front over
western Wyoming this afternoon. Leeside trough/warm front pushing
out of the Panhandle into western Nebraska. Pretty solid cloud
shield over eastern portions of the CWFA has helped keep winds
down so far today, but we are beginning to see some breaks in the
clouds along and west of the Laramie Range. As this clearing area
moves over eastern parts of the CWFA...we could see a surge in
windspeeds once again. Seeing winds increasing out near Arlington
this afternoon with gusts to 57 mph at Halleck Ridge. Bordeaux and
Coleman have been hitting warning criteria pretty regularly the
past several hours. Latest VWP winds has been showing a slow
decrease in winds though, so possibility that the strongest winds
are done. Decided to let the current High Wind Warnings ride as
they are to see what happens when these breaks get over Laramie
County.
Attention turns to the potential for snow squalls late this
afternoon and evening. NAM12 Snow Squall Parameter indicating very
favorable possibilities of snow squalls as the front moves through
the area late this afternoon. This would be along and directly
behind the front as it moves through the area. HRRR and HIRES NMM
simulated radar forecasts targeting Converse/Niobrara Counties in
southeast Wyoming and the northern Nebraska Panhandle with
enhanced reflectivity after 22Z...possibly extending south into
Laramie County and the southern Panhandle after 02Z this evening.
Have continued advertising snow squalls in current weather stories
to give customers a heads up that snow squalls are possible.
Snow coming to an end rather quickly this evening. We get a little
break in the Craig to Casper gradients behind the front with
850/700mb height gradients decreasing to the low 30mtr range after
00Z this evening. They ramp up again towards 12Z Thursday...up to
near 60mtrs by 15Z. Thinking Arlington and Bordeaux could be
pretty windy Thursday (15Z to 22Z) tomorrow. Will let the evening
shift take another look at winds after current wind headlines end
to avoid any confusion.
Warming and dry trend Thursday into Friday. Another wind event
possible Friday night into Saturday as another shortwave
approaches from the west. GFS 700mb winds increase above 50kts
Friday night. Craig to Casper gradients back up near 60mtrs for
that timeframe.
.LONG TERM...(Saturday through Wednesday)
Issued at 230 PM MST Wed Dec 12 2018
Saturday...A progressive shortwave trough aloft moves from western
Montana in the morning to the eastern Dakotas by evening. Dry
conditions across our counties due to limited low and mid level
moisture. Mild day with high temperatures in the mid 30s to near 40
degrees at lower elevations west of Interstate 25, and mid 40s to
mid 50s to the east.
Sunday...Rather pronounced ridging aloft develops overhead producing
a dry and mild day.
Monday...The upper ridge axis moves off to our east with the flow
aloft turning southerly. Continued dry with limited low and mid
level moisture. With 700 mb temperatures near 2 Celsius, maximum
temperatures will be mild, in the mid 30s to mid 40s west of
Interstate 25, and mainly 50s east of I-25.
Tuesday...Slightly cooler with a cooldown at mid levels. The
atmosphere still looks too dry for any precipitation development.
Wednesday...A weak shortwave trough aloft may bring a few showers,
though dry weather looks more likely. Slightly cooler based on
thickness trends.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 401 PM MST Wed Dec 12 2018
Front approaching from the northwest this afternoon will create
bands of moderate snowshowers as it moves through southeast
Wyoming and Nebraska Panhandle. Do not think snow will last long
at any individual airport...but timing is difficult at best for
each location. Used TEMPO groups in the 00Z TAFS to cover the
snow. All snow should come to an end by 06Z tonight.
&&
.FIRE WEATHER...
Issued at 230 PM MST Wed Dec 12 2018
Minimal fire weather concerns as a cold front moves through the
area this afternoon bringing fairly widespread snow and colder
temperatures to the area. Not much in the way of snow
accumulations, most areas should see a half inch of snow or less.
Windy conditions will continue through the remainder of the week
with strong winds near Arlington and Bordeaux Thursday and then
another wind event Friday into Saturday. Afternoon humidity
expected to stay well above critical levels.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...High Wind Warning until 8 PM MST this evening for WYZ101-106-107-
110-115>118.
NE...None.
&&
$$
SHORT TERM...GCC
LONG TERM...RUBIN
AVIATION...GCC
FIRE WEATHER...GCC
Area Forecast Discussion
National Weather Service Grand Forks ND
948 PM CST Wed Dec 12 2018
.UPDATE...
Issued at 942 PM CST Wed Dec 12 2018
Issued a Winter Weather Advisory for the Red River Valley into
eastern North Dakota due to the potential for icing. The reasoning
behind this was due to reports of slick conditions in Pembina
County along with freezing rain reports in Griggs and Pembina
counties. Also latest high resolution guidance suggests the band
of mixed precipitation in the central Sheyenne River Valley will
continue eastward into the Red River Valley while also filling in
to the south potentially impacting the I-94 corridor. The
transition from mixed precipitation to snow is still expected
between midnight and 3 AM as the bulk of precipitation moves out
of the Red River Valley within Minnesota. Again the reason for the
advisory is due to icing potential rather than snow amounts.
UPDATE Issued at 731 PM CST Wed Dec 12 2018
Messaging and forecast remains largely on track from previous
issuance. Some reports of freezing drizzle and drizzle/light rain
were reported near Devils Lake, with intermittent transitions to
light snow under higher radar returns (confirmed with report in
Langdon). Current observations from regional RWIS data indicates
road temperatures are beginning to dip below freezing. This along
with wet-bulbing potential will mean future liquid precipitation
will have the potential to freeze on contact. With this in mind,
still thinking a glaze will be possible for locations mainly west
of the Red River Valley, especially in the Devils Lake Basin and
northern Valley. The main transition of wintry mix to snow should
occur between midnight and 3 AM. Light snow still expected with
generally under 1 inch expected, possibly isolated 1-2 inches in
Minnesota early Thursday morning.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 314 PM CST Wed Dec 12 2018
This evening into the overnight with see another weakly forced
band of precipitation move across the area. With a dry warm layer
slow to saturate and cool, max wet bulb aloft temps on the RAP
near 5c, some precipitation will be mixed with freezing rain or
ice pellets before becoming all snow. Most intense precip appears
to hold off in the valley until after 10pm and exits by dawn. Hi
resolution models split the area with precip confined to areas
along the SD/ND border and along the international border.
However ensemble guidance shows the spread of solutions still
giving FAR and GFK up to 0.15" of precip. As a result will keep
the messaging the same with a glaze of ice possible valley and
west, most likely in SE ND, and snowfall amounts generally a half
to an inch with a locally higher amount possible in NW MN.
During the day Thursday westerly winds at the surface will help
dry out the lower layers clearing skies and allowing a sunny and
relatively warm day with temps reaching into the low 30s south
with upper 20s north.
.LONG TERM...(Thursday night through Wednesday)
Issued at 314 PM CST Wed Dec 12 2018
After a couple of mixed pcpn events, the weather looks to take a
quieter tack from Fri through the weekend into early next week.
Milder air returns on Fri through Sat, with 850 temps progged to
rise to between +5 and +10 C as upper ridging becomes established
over the northern plains.
Major deterministic guidance depicts a quick moving short wave that
should stay well north of the International border Sat/Sun; the
current forecast remains bone dry. Enhanced high amplitude ridging
is likely to develop from Big Sky to Southern Plains early next
week, adding to the likelihood of above average and above freezing
daytime temps. his band
So dry and mild will describe the extended forecast timeframe, 30s everywhere
with low 40s south Fri and Sat, cooler Sun and Mon before warming up again for
the middle of next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 552 PM CST Wed Dec 12 2018
Most locations will see IFR conditions through the overnight
excluding KDVL which will remain in MVFR. As the system moves
east, light freezing rain or drizzle along with snow.
Precipitation ends west to east early Thursday morning with KBJI
being the last to dry after sunrise Thursday morning. VFR
conditions follow after the system departs to the east Thursday.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Winter Weather Advisory until 3 AM CST Thursday for NDZ006>008-
014>016-024-026>030-038-039-049-052>054.
MN...Winter Weather Advisory until 3 AM CST Thursday for MNZ001>004-
007-029.
&&
$$
UPDATE...CJ
SHORT TERM...JK
LONG TERM...WJB
AVIATION...CJ
Area Forecast Discussion
National Weather Service Jacksonville FL
1011 PM EST Wed Dec 12 2018
...WARMER TONIGHT UNDER HIGH CLOUDS...
...WIDESPREAD RAINFALL FRIDAY WILL PROLONG AND/OR WORSEN RIVER
FLOODING ACROSS PARTS OF THE SUWANNEE RIVER VALLEY AND POTENTIALLY
INLAND SOUTHEAST GEORGIA...
.UPDATE...
Warmer with mostly dry conditions tonight as surface high pressure
ridge center builds offshore of the SE Atlantic coast. Abundant
high clouds will limit fog formation and keep temperatures more
mild generally in upper 30s to low 40s inland, to mid/upper 40s
toward the St. Johns River basin and Atlantic coast. Removed frost
from forecast given high clouds, but did include some patchy sea
fog drifting inland from the Atlantic along the SE GA coast where
temps and water temps were in the mid/upper 50s and BQK reported
recent restriction. HRRR advertised reduced visibility lingering
under the low level ridge axis across coastal SE GA through the
night. A low chance of coastal showers will lift up the NE FL
coast early Thu morning with increasing low level clouds as a
coastal trough morphs into a lifting warm front.
&&
.AVIATION...
VFR conditions tonight, with a very low chance of sea fog
impacting SSI based on observations at BQK, water temps/surface
temps in the mid/upper 50s and latest HRRR model run. Elsewhere
abundant high clouds will limit fog potential. Winds transition to
ESE through Thursday with restrictions to MVFR most probable at
SGJ in the afternoon, shifting northward up the coast through the
evening with a low chance of showers as warm front lifts northward
over the area. Further restrictions expected into Thu night.
&&
.MARINE...
Surface high pressure will build offshore of the southeast Atlantic
coast through Thursday. Light ESE winds 10 kts or less tonight
with combined seas 3 ft or less. Some sea fog potential near the
SE GA coast tonight. South winds will increase over the waters
ahead of an approaching front Thursday night with advisory
conditions expected for at least the outer waters.
Rip Currents: Moderate risk Thursday.
&&
.HYDROLOGY...
Moderate flooding continued this evening along the Alabaha basin,
with minor flooding along the Satilla and Altamaha.
Significant river rises expected this weekend due to widespread
heavy rainfall Friday, which will prolong current flooding issues
and even worsen flooding in some areas across inland SE GA and
the Suwannee River basin.
Latest forecast guidance advertised White Springs and Suwannee
Springs along the Suwannee River rising into Moderate flood stage
this weekend with 3-4 inches of rainfall. Ongoing flood issues
near Suwannee Springs Camp and Fox Hollow will continue (potentially
worsen) into the weekend.
Interests near flooded rivers/tributaries across SE GA and the
Suwannee River Valley, please closely monitor the latest river
forecasts and heed advice of local emergency management.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 37 65 57 68 / 0 10 70 90
SSI 49 63 58 68 / 0 30 50 80
JAX 42 67 60 73 / 0 20 50 90
SGJ 48 67 63 73 / 0 30 40 80
GNV 43 70 61 74 / 0 10 70 90
OCF 45 71 62 75 / 0 10 60 80
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&
$$
Enyedi/Bricker
Area Forecast Discussion
National Weather Service North Platte NE
518 PM CST Wed Dec 12 2018
.SHORT TERM...(This evening through Thursday)
Issued at 319 PM CST Wed Dec 12 2018
A potent mid level shortwave will dive southeast across the Rockies
and be located across northern Texas Thursday. Mid-level
frontogenesis (FGEN) develops late this afternoon and evening across
northwest Nebraska as the system passes to the west. Light rain
changing to light snow is likely across portions of northern
Sheridan county this evening, with perhaps up to an inch of
accumulation across northern Sheridan county in the Pine Ridge. The
band of mid-level FGEN weakens and shifts east overnight. Some light
rain and snow is possible as this occurs across north central
Nebraska, but as of now amounts look very light. Temperatures will
actually rise into the mid 30s later this evening as a strong
Pacific cold front associated with the system crosses the area. By
morning temperatures will drop into the upper 20s to near the
freezing mark. Any wet roadways from the light precipitation could
freeze and become slick as the temperatures drop.
The other story will be the strong gusty winds. NAM Nest and HRRR
both show potential for several hours of 40 mph wind gusts starting
this evening and lasting into Thursday morning. The stronger winds
will help mix the atmosphere and will help boost highs into the
upper 30 to around 40F by Thursday afternoon.
.LONG TERM...(Thursday night through Wednesday)
Issued at 319 PM CST Wed Dec 12 2018
Snowpack will begin to fade as above normal temperatures take hold
across western and north central Nebraska. Upper level ridging
will combine with a Pacific airmass to bring the mild weather.
Highs in the 40s to lower 50s are expected daily Friday into early
next week.
As snow melts and winds turn south, a little better low level
moisture will be in place early next week. This could allow for
some patchy late night and early morning fog potential.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 519 PM CST Wed Dec 12 2018
Approaching cold front will bring light snow showers across
northern Nebraska this evening. Brief periods of MVFR conditions
are possible late tonight at the KVTN terminal. After snow
showers clear out, strong northwest winds will develop with gusts
exceeding 35 mph likely for much of Thursday morning before skies
clear and winds die down after midday.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Taylor
LONG TERM...Taylor
AVIATION...Buttler/Jurgensen
Area Forecast Discussion
National Weather Service Pueblo CO
848 PM MST Wed Dec 12 2018
.UPDATE...
Issued at 840 PM MST Wed Dec 12 2018
Updated to adjust winds and precipitation chances this evening. Winds
are currently gusting 50 to 55 mph behind the front and should
continue south across the Plain through morning. For the most part
precipitation is behaving with minor accumulations on the Palmer
Divide and an inch or two expected over the Raton Mesa area.
Mozley
&&
.SHORT TERM...(This evening through Thursday)
Issued at 241 PM MST Wed Dec 12 2018
...Strong winds tonight with some squally periods of snow possible
mainly along the I-25 corridor...
Currently...
Skies over the lower elevations were mostly clear and temps were
primarily in the 60s. Gap areas were living up to their name-sake as
winds at Pueblo and Walsenburg were quite gusty, while over the rest
of the plains winds were light. Mtn tops were very windy as Monarch
was reporting hurricane force wind gusts (>65 knots).
Surface obs along with sat pix and hi res guidance was showing the
front/pre frontal trough generally extended from the GJT area
northeast to CYS and into the Dakotas. Temps behind the front were
in the 30s and 40s, while in advance of it temps were in the 50s and
60s.
Tonight...
Strong winds are the main concern. Nearly all HRRR runs showing
winds of 45-50 knts tonight across a large majority of the plains.
Front will cross COS region aoa 6 pm and move across PUB at 7 pm. It
will move through the rest of the plains during the remainder of the
evening hours. It appears at this time the strongest winds will
occur during the 04 UTC through 09 UTC time frame across the plains.
As for snow...hi res guidance shows best chance of squally weather
across the COS region from the 7-9 pm time frame, with all the
precip moving out by midnight. some gusty rain/snow showers may
event make it all the way down to Pueblo during the evening hours.
Best chance of some heavier snow will be down in the Spanish
Peaks/Raton Mesa region between 04 and 10 UTC, with the heaviest
accums falling across eastern Las Animas county. 1-2 inches will be
possible with locally heavier amounts.
Due to the winds and snow, issues a winter weather advisory for the
Spanish Peak/Raton Mesa region. Snow is not gonna amount to much,
but it could be locally heavy for a bit and it`s gonna blow around
given the winds.
Over the far eastern plains, dont really see much in the way of
precip; primary threat will be strong winds through the nighttime
hours, with peak gusts to 60 to 65 mph.
For the mtns...wind driven snow will continue along the contdvd this
evening, decreasing after midnight. 2-4" of snow will be possible.
The heaviest snow will occur over the central mtns. Local 2-4
amounts will also be possible over the souther Sangre De Cristo mtns.
Tomorrow...
Winds will slowly subside through the day from Northwest to
southeast. Best chance for the strongest winds to continue will be
over the far southeast plains down along the CO/NM and OK borders,
and have continued the high wind warning through late tomorrow
afternoon over this region.
It should be dry throughout the day tomorrow, although I cannot rule
out a stray shower over the far SE plains early in the day.
Although max temps will be in the 40s tomorrow, it will feel a lot
colder for any folks who must be outside tomorrow.
.LONG TERM...(Thursday night through Wednesday)
Issued at 241 PM MST Wed Dec 12 2018
...Quiet December Weather Pattern Setting Up...
Upper high pressure will build in over Colorado Friday resulting in
a period dry and mild weather. Temperatures should be above average
through the entire extended forecast period with no precipitation
expected. Having said this, there are a couple of caveats. First,
there is a weak disturbance poised to move through the northern
Rockies on Saturday. At the present time, this system is forecast
to pass by to the north of Colorado, bringing no precip to southern
Colorado. Confidence is pretty high that this system will not
interfere with the current dry and mild forecast for the weekend. Of
more interest is the pattern evolution for early next week. Late
Monday through Wednesday, a large, moist low pressure system is
forecast to develop and move east across Arizona and New Mexico,
almost missing Colorado entirely. However, the current track does
have it moving by pretty close. Any deviations in the path that
develop between now and early next week could certainly alter the
current dry and mild forecast. It is December after all.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 241 PM MST Wed Dec 12 2018
Main concern is strong winds at KCOS and KPUB tonight into tomorrow.
Cold front will cross the region aoa 01-02 UTC. Prior to FROPA, WNW
winds will be gusty, especially at KPUB. Once winds shift to north,
winds will become strong and last into the nighttime hours. Still
could see some snow-squally weather between 02-05 UTC at KCOS and
even possibly KPUB. Winds will be strong, with gusts to 50 knots out
of the question, especially during the 04 UTC and 09 UTC time
frame.
KALS will see some breezy conditions, but not nearly as strong as
KPUB and KCOS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
High Wind Warning until 6 AM MST Thursday for COZ084>086-089-095-
096.
Winter Weather Advisory until 2 AM MST Thursday for COZ087-088-
094.
High Wind Warning until 5 PM MST Thursday for COZ094-099.
High Wind Warning until 8 AM MST Thursday for COZ093-097-098.
&&
$$
UPDATE...MOZLEY
SHORT TERM...HODANISH
LONG TERM...LW
AVIATION...HODANISH