Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/24/23
Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
734 PM MST Sat Dec 23 2023
...New UPDATE...
.UPDATE...
Issued at 728 PM MST Sat Dec 23 2023
Cancelled the Winter Weather Advisory for the Taos area, Chuska
Mountains, west central mountains, and southwest mountains;
however, will keep the Winter Storm Warning going for the northern
mountains through at least the evening. Added patchy freezing fog
after midnight into early Friday morning around Taos and Gallup.
A Pacific cold front that will arrive late this evening is
forecast to usher drier low level air into the state, especially
from Farmington to Albuquerque and Santa Fe. There is still a
chance for some freezing fog in these locations, but it appears to
be decreasing due to the dry air advection behind the front.
&&
.SYNOPSIS...
Issued at 250 PM MST Sat Dec 23 2023
Wintry precipitation will continue across portions of northern and
central New Mexico into tonight. A few thunderstorms across eastern
New Mexico will be capable of strong winds, diminishing in the
evening hours. Additional snowfall accumulations overnight will
favor the western and northern mountains and their adjacent
highlands. Drier conditions expected Sunday, with lingering showers
favoring the northeastern high terrain. Colder temperatures will
prevail Sunday and breezy conditions across eastern New Mexico will
result in frigid wind chills. Cold temperatures persist Monday
into Monday night amongst dry conditions and mostly light winds.
A slow warming trend is expected through Thursday all areas.
&&
.SHORT TERM...
(This evening through Sunday night)
Issued at 250 PM MST Sat Dec 23 2023
Upper low tracking over central New Mexico this afternoon with a
mixed bag of rain, snow, fog, wind and thunderstorms. General model
trends haven`t changed much but HRRR suggests the upper low may
remain intact as it moves over north central/northeast New Mexico
tonight. Therefore scattered showers along with patchy fog/freezing
fog would continue over the northwest, west central and north
central through this evening in the northwest flow then slowly
diminish after midnight as drier air starts to invade the region.
Therefore, will keep the current Winter Weather Warnings and
Advisories going. The line of thunderstorms over eastern New Mexico
this afternoon was progressing into Texas at this time although
can`t rule out an isolated lightning strike through early evening.
High pressure will build down the eastern plains Sunday while
northwest flow aloft may bring additional shortwave energy, keeping
the chance for snow showers going over the Sangre de Cristo
mountains and along the far northeast New Mexico border where patchy
blowing snow is possible. North winds may be strong enough for a few
hours Sunday morning into the afternoon to meet Wind Advisory
criteria over Union County but unsure how much snow may be
associated to produce blowing snow, so will refrain from issuing any
highlights for that area at this time.
High temperatures Sunday will be near to about 10 degrees colder
than normal. Lows Sunday night will be quite a bit colder (about 10-
15 degrees) than tonight`s lows, and generally below normal.
&&
.LONG TERM...
(Monday through Friday)
Issued at 250 PM MST Sat Dec 23 2023
As upper level low pressure churns across the Great Plains, a regime
of northwest flow sets up over northern and central NM on Monday.
This will bring slightly elevated sfc winds to portions of the
state, particularly the central mts and their adjacent highlands. As
the low spins to our northeast, a reinforcing shot of CAA will bring
temperatures down another few degrees nearly areawide. This combined
with the brisk west and northwest winds will set the stage for a
chilly scene Monday, and while winds will relax in the evening,
especially frigid temperatures are expected Monday night. The upper
low pushes towards the Midwest on Tuesday, with a northerly jet max
being draped over NM. More widespread breezy northwest winds will be
the result in the afternoon. A slight rise to pressure heights will
allow for a modest rebound of a few degrees to afternoon highs
areawide. High pressure to our west begins to mosey over the
Intermountain West Wednesday, bringing a more substantial
increase in temperatures to take place. Variations of the high
pressure aloft will persist through the remainder of the work
week, creating mostly light winds and dry conditions.
&&
.AVIATION...
(00Z TAFS)
Issued at 443 PM MST Sat Dec 23 2023
Rain and snow showers producing MVFR and IFR conditions are
forecast to taper off over western areas during the evening, while
lingering tonight and Sunday over the northern mountains
(especially near the CO border). The main forecast challenge
tonight is figuring out where low clouds and fog will develop
along and west of the central mountain chain after midnight,
producing IFR conditions until mid morning Sunday. Locations that
received significant rain and/or snow will be favored for low
clouds and fog, but drier northwest flow is forecast to overspread
central and western areas tonight, decreasing confidence some in
places like KSAF, KABQ, KAEG, and KFMN. At this time TAFs err on
the side of caution in these locations. Downslope flow along the
east slopes of the central mountain chain should inhibit low cloud
and fog development there. Meanwhile, a gusty backdoor cold front
is forecast to dive southward through the eastern plains late
tonight with drier air and strong north winds that will linger
through midday Sunday. The strongest winds look to impact KCAO,
where they may gust up to 45 knots.
&&
.FIRE WEATHER...
Issued at 250 PM MST Sat Dec 23 2023
Critical fire weather conditions are not anticipated through the end
of next week. An amplified weather pattern with a sharp upper ridge
axis from Arizona through Montana and an upper trough to the east
over New Mexico are forecast through the middle of next week,
keeping temperatures near to below normal. Ventilation Sunday will
be fair to poor west and good over the east with areas of widespread
poor ventilation for the rest of next week.
This afternoon`s thunderstorms over southern and eastern New Mexico
will move into Texas while showers over the north and west will
slowly diminish but may persist after midnight before dissipating.
Snow showers could continue over the Sangre de Cristo mountains and
along far northeast New Mexico Sunday although any accumulations
would likely be light. Gusty northwest to north winds are expected
tonight and Sunday as the upper storm system exits to the east of
the state and surface high pressure builds down the eastern plains.
Chances for precipitation may not return until the final day of 2023
or New Year`s Day.
&&
.PRELIMINARY POINT TEMPS/POPS...
Farmington...................... 23 38 13 38 / 30 0 0 0
Dulce........................... 19 35 4 34 / 60 10 5 0
Cuba............................ 21 36 10 34 / 60 0 0 0
Gallup.......................... 18 40 7 40 / 40 0 0 0
El Morro........................ 20 37 8 37 / 60 0 0 0
Grants.......................... 21 41 10 40 / 30 0 0 0
Quemado......................... 23 38 11 39 / 40 0 0 0
Magdalena....................... 28 43 19 42 / 10 0 0 0
Datil........................... 25 39 15 39 / 20 0 0 0
Reserve......................... 22 45 12 48 / 20 0 0 0
Glenwood........................ 29 48 24 51 / 20 0 0 0
Chama........................... 15 30 -1 30 / 60 10 10 0
Los Alamos...................... 23 37 14 32 / 50 5 5 0
Pecos........................... 23 38 12 34 / 50 5 10 0
Cerro/Questa.................... 18 32 5 28 / 40 20 20 0
Red River....................... 19 32 -1 26 / 50 20 20 0
Angel Fire...................... 16 29 -6 27 / 50 20 20 0
Taos............................ 22 35 6 30 / 50 10 10 0
Mora............................ 21 37 5 33 / 40 10 10 0
Espanola........................ 23 42 10 39 / 50 0 5 0
Santa Fe........................ 24 37 14 32 / 50 5 5 0
Santa Fe Airport................ 26 40 16 35 / 40 0 5 0
Albuquerque Foothills........... 27 43 20 40 / 40 0 0 0
Albuquerque Heights............. 30 45 23 41 / 30 0 0 0
Albuquerque Valley.............. 26 47 17 43 / 30 0 0 0
Albuquerque West Mesa........... 29 46 22 42 / 30 0 0 0
Belen........................... 30 49 21 44 / 20 0 0 0
Bernalillo...................... 29 45 20 42 / 40 0 0 0
Bosque Farms.................... 28 47 19 43 / 30 0 0 0
Corrales........................ 29 46 20 42 / 30 0 0 0
Los Lunas....................... 29 48 21 43 / 20 0 0 0
Placitas........................ 27 43 19 37 / 40 0 0 0
Rio Rancho...................... 29 45 21 41 / 30 0 0 0
Socorro......................... 31 51 23 46 / 5 0 0 0
Sandia Park/Cedar Crest......... 26 38 17 33 / 40 0 0 0
Tijeras......................... 28 41 18 35 / 40 0 5 0
Edgewood........................ 27 40 15 34 / 40 0 0 0
Moriarty/Estancia............... 27 41 12 36 / 30 0 0 0
Clines Corners.................. 25 38 14 33 / 30 0 5 0
Mountainair..................... 27 41 17 37 / 30 0 0 0
Gran Quivira.................... 28 43 18 39 / 20 0 0 0
Carrizozo....................... 32 47 23 44 / 10 0 0 0
Ruidoso......................... 30 43 21 41 / 10 0 0 0
Capulin......................... 26 31 10 32 / 20 30 10 0
Raton........................... 27 35 9 36 / 20 20 20 0
Springer........................ 27 40 10 37 / 10 5 10 0
Las Vegas....................... 24 39 13 37 / 30 10 10 0
Clayton......................... 32 39 19 39 / 5 0 0 0
Roy............................. 28 41 16 37 / 5 5 10 0
Conchas......................... 30 45 20 43 / 5 5 5 0
Santa Rosa...................... 33 48 22 42 / 10 5 5 0
Tucumcari....................... 33 48 20 43 / 10 0 0 0
Clovis.......................... 34 47 21 44 / 20 0 0 0
Portales........................ 36 49 22 45 / 10 0 0 0
Fort Sumner..................... 34 51 23 45 / 5 0 0 0
Roswell......................... 35 58 25 50 / 0 0 0 0
Picacho......................... 36 53 22 49 / 0 0 0 0
Elk............................. 33 52 22 50 / 0 0 0 0
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning until 5 AM MST Sunday for NMZ210-211-213-
214.
&&
$$
SHORT TERM...99/44
LONG TERM....12
AVIATION...44
Area Forecast Discussion
National Weather Service Buffalo NY
1020 PM EST Sat Dec 23 2023
.SYNOPSIS...
Weak low pressure will continue to move across the region through
Sunday morning, with periods of light rain or drizzle tonight before
gradually ending from west to east on Sunday. Some wet snow may mix
in at times across the higher terrain east of Lake Ontario but
little or no accumulation is expected. The murky airmass will also
lead to some fog later tonight into Sunday morning. Dry weather will
then return later Sunday through Christmas Day, along with well
above average temperatures.
&&
.NEAR TERM /THROUGH SUNDAY/...
Radar shows primary slug of widespread precipitation has moved east
of Lake Ontario with scattered/showery precipitation from the Finger
Lakes westward. Back edge of showers are over eastern Lake Erie. Sfc
analysis and RAP forecasts show weak low has now moved to western
Lake Ontario. Temps are mainly above freezing, and even just inland
to the east of Lake Ontario have now rose just above freezing. Still
could be isolated icy spots on untreated roads farther inland east
of Lake Ontario.
A weak mid level trough will continue to drift east across the
eastern Great Lakes tonight, evolving into a weak mid level closed
low Sunday over northern NY. A weak surface low will become nearly
vertically stacked beneath the mid level circulation overnight, then
wash out on Sunday as it shifts ever so slowly to eastern Lake
Ontario. DPVA and moisture transport ahead of the shortwave will
continue to support patchy light rain and drizzle the rest of the
night into Sunday morning. A few upslope showers may linger into
early Sunday afternoon east of Lake Ontario.
Precipitation type will be all rain in the vast majority of the area
through Sunday. The one exception will continue to be across the
North Country, where some wet snow will mix in at times especially
across the higher terrain of the Tug Hill and western foothills of
the Adirondacks where boundary layer and surface temperatures will
be slightly colder. Expect little or no accumulation in these areas.
Abundant, deep low level moisture behind the departing system may
allow for some drizzle to continue overnight through Sunday morning
even after the more organized rain exits. Some fog will expand as
well. Weak SW flow along and south of the sfc low will bring in
higher dewpoints upper 30s to even lower 40s based on upstream obs.
These higher dewpoints flowing across colder ground (soil temps in
the mid to upper 30s per NY Mesonet) along with drying aloft should
lead to the expansion of fog overnight. Beefed up fog coverage
overnight into Sunday morning over western NY given the trends. Not
sure widespread dense fog occurs though.
Temperatures will continue to run well above average. Lows tonight
will be in the mid to upper 30s in most areas (may stay around 40
over far western NY), with lower 30s limited to Lewis County. Highs
Sunday will be in the mid 40s in most areas, with upper 30s to lower
40s for the North Country.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
A brief period of quiet, mild weather will ensue Sunday night right
through Christmas Day. The culprit will be high pressure extending
westward from the Gulf of Maine across NY State. Highs Monday are
expected in the upper 40s (east of Lake Ontario) to the 50s
elsewhere, approximately 20 degrees above normal. In fact, it is
very likely that all three of our climate sites (Buffalo, Rochester,
and Watertown) will have high temperatures in the Top 10 warmest on
record for Christmas Day.
The surface high to our east begins to depart Monday night this as
the mid-level low over the Colorado Rockies continues to drift east
into the nations midsection. Meanwhile...the surface reflection with
this complex system will send an occluded front into our region late
Monday night into Tuesday. The initial wave of light rain will enter
far WNY just before daybreak, then precipitation will become
intermittent or spotty. That said...the occluded front likely won`t
make much progress east or have much of an impact for our far
eastern counties(North country) until late Tuesday. Anticipating
much of the day there will see little precipitation until a
secondary wave develops by Tuesday night along the front, and then
draws deep moisture northward into our region. If current model
trends hold (12Z)...Tuesday night looks wet with widespread rain
developing across the entire region. QPF wise...area basins through
Tuesday night west of the Finger Lakes region will see 0.25 to 0.50
inches with isolated higher amounts. Much lighter amounts of 0.10 to
0.25 inches will be found from the Finger Lakes region into the
North Country. Again...no snow (too warm) with the initial portion
of this system. Temps on Tuesday again will be well above normal
with highs in the 40s to low 50s. Tuesday night lows will be found
in the 40s supporting an all rain event areawide.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Quite a bit of uncertainty in the forecast due to model
disagreements for the second half of next week (Wednesday through
Sunday). In general, a potent mid-level low within the sub-tropical
jet will be overhead of the central Mississippi Valley Wednesday
morning. Throughout the day Wednesday into Thursday this low will
merge with a shortwave trough within the polar jet dropping
southeast out of western portions of the Ontario province. By
Thursday the merged pattern will place a large longwave trough
spanning from the central Great Lakes to the Gulf of Mexico, where
the trough will remain in place through the end of the week and
allow for multiple waves to ripple through.
Overall this will support chances for precipitation throughout the
second half of the week and into the weekend. Initially
precipitation will start off as all rain then with the trough
in place, cooler air will filter in across the region by Friday
and Saturday supporting snow. This also being said, temperatures
will gradually become colder from highs on Wednesday in the
upper 40s to the low 50s to highs on Saturday in the low to mid
30s.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
Weak low pressure will continue to move slowly east across the
eastern Great Lakes tonight through Sunday, with periods of light
rain or drizzle tonight before gradually tapering off from west to
east Sunday. Some wet snow may mix in at times across the higher
terrain of the Tug Hill and western Adirondacks, otherwise all rain
is expected.
IFR and even LIFR conditions have formed quickly over western NY
this evening. Plan on conditions to continue deteriorating to at
least low end MVFR farther eastward the rest of the night, including
ROC and ART. The low conditions will manifest as low stratus, but
there will also be IFR fog across Western NY and higher terrain as
well later tonight through Sunday morning. Some risk of dense fog
late tonight into mid morning Sunday over western NY, so have placed
TEMPO groups in at IAG, BUF and JHW for LIFR vsby. Though VSBY will
improve by Sunday afternoon, areas of IFR/MVFR CIGS will continue.
Outlook...
Monday...VFR.
Tuesday and Wednesday...MVFR to IFR with periods of rain.
Thursday...Areas of MVFR with rain showers likely, possibly mixing
with some wet snow across higher terrain.
&&
.MARINE...
Southeast winds around 15 knots will produce choppy conditions over
the northeast end of Lake Ontario tonight, and again Monday
afternoon through Tuesday, but winds and waves are expected to
remain a little below Small Craft Advisory criteria. Otherwise,
winds will remain light for the west end of Lake Ontario and Lake
Erie through the middle of next week.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.
&&
$$
SYNOPSIS...Hitchcock/JLA
NEAR TERM...Hitchcock/JLA
SHORT TERM...AR
LONG TERM...EAJ
AVIATION...Hitchcock/JLA
MARINE...Hitchcock
Area Forecast Discussion
National Weather Service Dodge City KS
715 PM CST Sat Dec 23 2023
.KEY MESSAGES...
- Rain showers and limited thunder are expected Saturday night.
- A strong cold front is expected Sunday morning, followed by
intense northwest winds Sunday. Gusts to near 50 mph are
possible.
- Light snow and blowing snow is expected along I-70, and
northeast of Dodge City, Christmas Day.
&&
.UPDATE...
Issued at 715 PM CST Sat Dec 23 2023
Sharp trough axis was approaching from the west as expected
early this evening, with a shortwave embedded in the trough
focusing ascent and forcing a line of convective showers and
limited thunder southwest of DDC as of 7 pm. Several cloud to
ground lightning strikes have been observed in Kansas on the
lightning detection network. Forcing is strong, and effective
bulk shear near 40 kts per mesoanalysis supports organized
convection, but instability is very weak (CAPE < 400 J/kg),
severely limiting updraft intensity. Still, infrared satellite
cloud tops to near -60C are impressive for December, and locally
heavy rainfall and lightning will accompany this line for the
next several hours. Pops remain in the likely to definite
category for this evening for this line of forced convection,
with pops dwindling quickly after midnight as SW KS gets
dryslotted. Aligned pops with this thinking.
An intense cold front is scheduled to arrive near or just after
sunrise, followed by intense northwest winds Sunday. Followed or
went above the strongest wind guidance available, with gusts
flirting with high wind warning criteria (58 mph) northwest
zones near US 83 by midday. Stratus, north winds and strong cold
advection will bring a strong winter reality check on Christmas
Eve, with temperatures showing a non-diurnal curve downward
through the 30s in the afternoon, with wind chills in the 20s.
&&
.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 200 PM CST Sat Dec 23 2023
19Z observations display a large upper level trough centered
from Montana to New Mexico with a developing 556 dm low in New
Mexico. Ahead of the low upper level lift is being shown in
several areas from southwest Kansas to central New Mexico with a
few lightning strikes from time to time to our south. At the
surface the advertised stronger winds from the south are in
place with gusts in the 30-40 mph range and dewpoints in the
upper 40s to lower 50s show we have plenty of lower level
moisture to work with.
Tonight the various CAM models are in agreement of a line of
showers and embedded thunderstorms moving in from northeast New
Mexico to southwest Kansas after sunset. This area of rain will
have modest CAPE to work with through the evening (~100-250
J/kg) and increasing 0-6 km bulk shear after midnight. Severe
weather should not be expected however it wouldn`t be surprising
if we have some pea to marble sized hail. Overall the highest
percentage of 0.25 inches of rain or more (~80%) continues to be
mainly east of a Hays to Dodge City line...and lesser amounts
are to be expected as you go west. Winds early in the evening
will remain strong and then we should see a brief calm period
from midnight to sunrise as the surface low moves in from
eastern Colorado to western Kansas. Temperatures tonight should
remain mild (40s-50s) with the moisture and winds in place and
many areas will likely have their warmest temperatures for
Sunday occurring in the early morning hours as the strong cold
air advection will enter into the region by sunrise Sunday
morning.
For Sunday the rain showers in our east should depart into
central Kansas as the cold front quickly sweeps out the
moisture. In its place we will see winds sharply increase out of
the northwest to 25-35 mph with higher gusts. 850 mb
temperatures will be falling throughout the day and be the
lowest in the afternoon (around -4(C)). With the wind, cold air
advection, and clouds this will set the stage for temperatures
cooling through the morning and then becoming steady in the mid
30s by afternoon. A few CAMs such as the HRRR and ARW try to
develop some post frontal snowshowers mainly in our far western
and northern regions but the bulk of the best lift will be
confined to northwest Kansas and Nebraska.
Sunday night the winds should relax a bit however they will
still be breezy at 10-20 mph and with the coldest of the air
moving in and some clearing I went with the NBM10th percentile
lows which would be in the upper 10s to mid 20s.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 219 PM CST Sat Dec 23 2023
We will continue to be under the influence of a large closed
upper low for Monday and Tuesday as medium range ensemble
clusters show the upper low to remain fairly stationary roughly
around the KC metro area through Wednesday morning. What that
means for our weather is continued colder temperatures for the
start of the week with highs in the 30s to lower 40s.
What will need to be monitored is the increasing confidence in
light accumulating snows across the I-70 corridor and snow
potential as far south as Dodge City to Pratt. The Euro
ensembles are currently the most aggressive solution with a
stout area of upper level lift on the west and northwest side of
the low and the probabilities of at least 1 inch of snow from
Monday night through Tuesday range from 100% at Hays to 30-40%
along the highway 50 corridor. GFS ensembles are slightly
different as it keeps the stronger lift farther north and west
and keeps the accumulations located mainly along and north of
I-70. I will stick with the better chances of accumulating snow
(1 inch or more) in our northern zones as they will have the
greatest likelihood (>80%) of being near the strongest lift
with lesser accumulations to the south.
By Wednesday a large ridge builds in the Rockies and should
push out the upper low and colder air. Temperatures should
moderate by the mid week into the upper 40s for highs. By Friday
the long term models hint at a large cold air mass mainly in the
Great Lakes region but we could get side swiped by some colder
air on the western periphery of the airmass. Precipitation
chances for mid to late week should be less than 10%.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 440 PM CST Sat Dec 23 2023
High confidence that flight conditions will remain rather poor
through the balance of this TAF period. Radar imagery at 2230z
showed a linear complex of thunderstorms in the Texas panhandle,
from near Dalhart to near Amarillo. This band of showers and
thunder is moving northeast, and will at least be near LBL this
evening warranting VCTS/CB. Thinking is this primary line of
convection will remain southeast of the other airports this
evening, so kept them out of this set of TAFs, but scattered
rain showers are still expected. Widespread IFR to MVFR stratus
is expected at all airports through the balance of this TAF
period. Strong south winds, gusting near 40 kts at GCK at 2230z,
will begin weakening at sunset, and continue weakening through
the night. An intense cold front is expected to clear all the
airports during the 12-14z Sun time frame, followed by intense
N/NW winds for the balance of daylight Sunday. NW gusts of
35-45 kts can be expected. Along with wind impacting aviation
operations, consensus of short term models suggests MVFR stratus
will hold at the airports through the balance of Sunday.
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Turner
SHORT TERM...Tatro
LONG TERM...Tatro
AVIATION...Turner
Area Forecast Discussion
National Weather Service Memphis TN
853 PM CST Sat Dec 23 2023
...New UPDATE...
.UPDATE...
Issued at 852 PM CST Sat Dec 23 2023
00Z upper air analysis shows a ridge of high pressure centered
off the Carolina coast with southerly low-level return flow over
the Lower Mississippi Valley this evening. 00Z KLZK/KOHX upper
air soundings indicate ample moisture up to around 700 mb with
some low-level shear assisting in producing some light rain
showers this evening near the Tennessee River. This aforementioned
ample low-level moisture and light to nearly calm winds have
resulted in the development of some fog over portions of West
Tennessee early this evening.
Short-term model trends indicate these rain showers will depart
the area in the next 2-3 hours with little if any potential for
rain thereafter for the remainder of the night. Will make some
additional adjustments to adjust timing of rain showers, duration
of fog, and other elements as needed.
CJC
&&
.SYNOPSIS...
Issued at 310 PM CST Sat Dec 23 2023
A few light showers will remain over the Mid-South through sunset
before a brief period of dry conditions heading into Christmas
Eve morning. An upper level low will then bring more widespread
showers, with a few pops of thunder, across the area Christmas Eve
afternoon through Christmas Day`s end. Cold and dry conditions
will follow these showers through the end of the workweek.
&&
.DISCUSSION...
(This evening through next Friday)
Issued at 310 PM CST Sat Dec 23 2023
A few NQA radar indicated light WAA showers ahead of a shortwave
trough will remain moving northeast across the Mid-South through
around sunset this evening. Rain-free conditions will set in
behind these aforementioned showers ahead of a shift in our
weather pattern tomorrow. A deep upper-level Colorado low with an
attached cold front will continue to push east before occluding as
it approaches the Mid-South, bringing more widespread showers
beginning tomorrow afternoon through Christmas day. A few pops of
thunder are possible in areas mainly south of I-40 late tomorrow
evening into early Christmas morning, though nothing to write home
about. Forecast PWATS are above normal at around 1.15" with QPF
values around 0.5"-1". Kinematics with this system are virtually
non- existent, precluding any severe threat for our holiday
festivities.
As the aforementioned front approaches the Mid-South, our pressure
gradient will tighten and increase our wind speeds with sustained
winds up to 20 mph, gusting up to 35 mph across our forecast area
tomorrow through Christmas morning. Highs will remain in the 60s
with lows in the 50s through Christmas Day. Cold, dry air will
follow the front decreasing our temperatures Tuesday and
Wednesday with highs in the upper 40s to mid 50s and lows in the
30s.
By mid-week, the aforementioned low will set up over the
Illinois/Indiana border dropping our temperatures and bringing
brisk winds with highs likely not leaving the 40s Thursday through
the weekend. An interesting thing to note is, if this same low
sets up more south, closer to our CWA, snow chances for our
northern most counties could enter the conversation late next
week. Though, Model guidance is still all over the place on these
supposed chances.
AEH
&&
.AVIATION...
(00Z TAFS)
Issued at 555 PM CST Sat Dec 23 2023
A transition to VFR remains on track this evening, behind exiting
-SHRA. NAM and HRRR models depict drier boundary layer air
spreading in from AL and the TN River Valley this evening, aiding
VFR probabilities at Midsouth terminals.
Wind will be the main impact Sunday, with gusts developing
ahead of an upper level trough. Marginal LLWS appears likely at
JBR and MEM. -SHRA may arrive at these two terminals as early as
21Z, but VIS-restricting rainfall rates will likely hold off until
closer to 00Z/25.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
PUBLIC FORECAST...AEH
AVIATION...PWB
Area Forecast Discussion
National Weather Service Marquette MI
801 PM EST Sat Dec 23 2023
.SHORT TERM...(Through tonight)
Issued at 323 PM EST SAT DEC 23 2023
Key Messages:
-Fog, some dense, to expand again tonight, mainly in central Upper
MI where s to sse winds upslope.
- Record high min temp to be set for today (12/23) at the NWS site
in Negaunee Township (Current record for 12/23 is 32F set 1979/2015)
Water vapor imagery and RAP analysis show a mid-level trof extending
from Alberta/Saskatchewan to the southern Rockies and ridging
downstream across much of the eastern U.S., extending n to Hudson
Bay. A strong positive height anomaly, 310m at 500mb, is centered
over northern Ontario. Under this flow regime, an unseasonably warm
and moist air mass is over the Upper Great Lakes today. 850mb temps
are 8-11C above the long term avg for this time of year across Upper
MI, and precipitable water is running 200-250pct of normal. With the
anomalous warmth and moisture for this time of year, low clouds
dominate Upper MI today, and while fog has diminished in coverage
and vis has improved for most, there are still a few spots with vis
1/2sm or less. Temps are currently running roughly 15-20 degrees
above normal, ranging from the upper 30s to mid 40s F.
Under an unseasonably warm air mass with abundant column moisture
and low clouds dominating, it will be an unseasonably warm night
tonight for late Dec. Temps will only fall back to 35-40F,
generally 10-15 degrees above the normal high temps for this time
of year. Here at NWS Marquette in Negaunee Township, we won`t fall
to 32F for the rest of the calendar day, so a new record high min
temp will be set for 12/23. Under continued sse sfc winds
tonight, fog will expand in coverage, mainly thru the central fcst
area where sse winds are an upsloping wind. Winds will be
increasing above the near sfc stability, so dense fog coverage
tonight may not be as extensive as last night. Might see a little
patchy -dz in the upslope areas as well later in the night.
.LONG TERM...(Sunday through Saturday)
Issued at 315 PM EST SAT DEC 23 2023
Key Messages:
- Temperatures averaging around 25F above normal Sunday through
Monday night.
- Areas of fog, locally dense, continue Sunday.
- Return to near normal temperatures with periods of lake effect
snow by Thursday/Friday.
Expansive positive time-mean 500 mb height anomaly will continue to
encompass most of Canada and some of the northern tier of the CONUS
through the end of the calendar year, resulting in a continued lack
of anomalously cold airmasses. Midlevel ridging will continue to
build into the upper Great Lakes Sunday ahead of a narrow full-
latitude trough moving across the Rockies. This trough will split,
with the northern portion heading up into Hudson Bay, and the
southern portion becoming a sprawling cutoff low drifting over the
central plains from the early to middle part of the upcoming week.
Another ridge building in the lee of the Canadian Rockies by the end
of next week has the potential to force troughing southward into the
upper Great Lakes by Thursday/Friday.
Pressure gradient will tighten Sunday ahead of an elongated cold
front moving east across MN. This will provide an advective boost to
the temps, and despite the lack of diurnal mixing due to the cold
ground, expect highs well into the mid-40s to near 50, some 20-25F
above normal. Some fog is likely to continue, especially over areas
that are upslope relative to southeasterly flow (basically the same
areas that have been observing it so far), as dewpoints climb into
the 40s. A band of rain along the front is likely to slow its
eastward progress Sunday night as it loses upper level support due
to the northern stream wave departing north, but rain is likely to
reach the central and west Sunday night. Continued mild Christmas
Day with periods of rain continuing across the northwest half. Rain
will likely fill in across the remainder of the UP from the south
Monday night as overrunning along the northern periphery of the
Plains cutoff moves into the area. It now appears very unlikely
(<10%) for any frozen precipitation Monday night into Tuesday, so
this will be a plain rain event with periods of rain continuing into
Tuesday. Low temperatures Sunday night and Monday night in the
upper 30s to low 40s will not only almost certainly set record
high mins, they are in the ballpark of the warmest December
overnight lows ever recorded at Marquette (current record 41F set
on 2 Dec 1982).
It`s possible that a midlevel dry slot moves in from the south on
Wednesday, so PoPs trend down to chance (40-50%) levels. There will
likely be a return to near seasonable temperatures by the end of the
week (Thu-Fri) as troughing is forced southward into the Great
Lakes. It`s likely to expect some accumulating lake effect snow in
north to northwesterly wind belts as well (50-60%). Cluster analysis
shows that uncertainty is tied to how quickly ridging builds back in
over southern Canada toward the end of the week, with quicker
ridging resulting in a more abbreviated lake effect period, and vice
versa.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 751 PM EST SAT DEC 23 2023
An unusually warm/humid air mass for this time of year along with
saturated/near saturated low-levels will ensure low clouds persist
thru this fcst period, especially at SAW due to upsloping sse winds.
At SAW, LIFR or lower conditions will prevail thru the fcst
period with conditions likely to remain almost continually blo
airfield landing mins thru Sun morning. At CMX, initial VFR
conditions will fall to MVFR by late evening/overnight, then
possibly to IFR Sun morning as winds begin to take on a more
favorable upslope se direction. At IWD, IFR cigs should lift to
low-end MVFR by late Sun morning due to increased mixing from
downsloping sse winds. Increasing winds above stable sfc based
layer will lead to LLWS developing Sun morning at IWD and CMX and
at SAW late Sun afternoon.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 315 PM EST SAT DEC 23 2023
Light south-southeasterly winds less than 20 kt will continue today,
gradually increasing tonight into Sunday. South-southeasterly gusts
of 20-30 kt are expected Sunday into Sunday night, highest over the
eastern half near the Canadian border, as the pressure gradient
increases ahead of an approaching low pressure system. Overlake
stability should limit gusts to mostly below gale criteria, although
some of the higher observing platforms could record gusts near 35 kt
at times.
As low pressure builds to the southwest with high pressure to the
north, strong northeasterly winds are expected to develop Monday
into Tuesday, especially over the western half. Gale probabilities
are greater than 80% Monday night into Tuesday over the west half,
with a 40-50% chance of exceeding 40 kt. Gale probabilities between
Stannard Rock and the eastern Lake Superior buoy are around 40-50%.
A Gale Watch will likely be needed. The pressure gradient weakens
Tuesday night, but elevated north-northeast winds at 25-30 kt are
possible at times through the end of the week.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Dense Fog Advisory until noon EST /11 AM CST/ Sunday for MIZ004-
005-010>013.
Lake Superior...
None.
Lake Michigan...
Dense Fog Advisory until 11 AM EST Sunday for LMZ221-248-250.
&&
$$
SHORT TERM...Rolfson
LONG TERM...Thompson
AVIATION...Voss
MARINE...Thompson
Area Forecast Discussion
National Weather Service Pocatello ID
155 PM MST Sat Dec 23 2023
.SHORT TERM...THIS AFTERNOON THROUGH SUNDAY NIGHT...
Post-frontal, wind-convergence-induced snowfall ongoing across
the Snake Plain corridor into the adjacent highlands to the
south/east is starting to slowly wane in coverage, and high-res
models continue this trend with lingering light snow showers
confined to only the ern highlands by 4-5pm, and ending everywhere
by midnight. Additional accumulations will range from a dusting
in the Snake Plain to 2 inches in some of our ern mntns. Motorists
should continue to be alert for slick conditions and adjust their
speeds accordingly, both due to falling snow and lingering icy
conditions from this morning. Meanwhile, winds continue to gust to
40 MPH spilling out of the Central Mntn valleys from Arco to
Dubois, and to 50 MPH in the Idahome/Malta area along I-84. Speeds
have already peaked, and winds regionwide should continue to
trend down between now and midnight. Overall guidance isn`t too
excited about fog development overnight (with the HRRR perhaps the
most aggressive), but given lighter winds, recent precip, and
decent clearing, hard to rule out at least patchy/localized
development. We were generous in adding patchy freezing fog to the
forecast accordingly, especially from the Shoshone lava beds and
Snake Plain into some of our srn/ern valleys. Expect low temps to
bottom out in the teens and single digits for most. Sun will be
mostly sunny and quiet as high pressure builds in from the west,
with highs in the mid-20s to low-30s. 01
.LONG TERM...MONDAY THROUGH NEXT SATURDAY...
The extended portion of the forecast doesn`t appear to have any
overly impactful weather in store for the region. On Christmas Day,
high pressure will be over the area which will keep things dry under
mostly clear skies. Northerly upper-level flow will keep things on
the cooler side of normal however. Forecast high temps reach right
around freezing, at best, in the warmest locations with much of the
area in the mid to upper 20s for daytime highs. As the week
progresses, the aforementioned high looks to remain in control
through Wednesday. There`s a hint of some potential troughiness
developing across the Pac NW Thu/Fri but models don`t seem to be
nearly as aggressive with it compared to previous days. Operational
models now look dry Thu/Fri as they hint at the ridge maintaining
control of local weather but the NBM still shows some scattered PoPs
regionwide. Given the uncertainty this far out, didn`t stray from
the NBM which keeps temps around seasonal norms and some potential
for precip in the Thu/Fri timeframe but as mentioned above, things
seem to be trending towards a drier solution throughout the extended
period. McKaughan
&&
.AVIATION...
MVFR/IFR conditions likely to continue for a few more hours at KIDA
and KPIH in association with falling snow and lower CIGs. This will
likely impact KDIJ to a lesser extent over the next few hours as
well. Hi-res models clear the region out quickly this afternoon
though with VFR conditions likely everywhere by later this evening.
Wouldn`t be surprised to see some localized BR development around
KIDA but this isn`t in the forecast at the moment. High pressure
builds in across the area into Sunday with light winds and mostly
clear skies expected tomorrow. McKaughan
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Phoenix AZ
452 PM MST Sat Dec 23 2023
.UPDATE...Updated 00Z Aviation Discussion.
&&
.SYNOPSIS...
A gradual warming and drying trend is expected this week in the
wake of the low pressure system that produced widespread rainfall
across the Desert Southwest. A return to slightly above normal
temperatures is expected late in the week as high pressure
predominates across the intermountain West.
&&
.DISCUSSION...
Latest RAP streamline analysis indicates the trough axis has
pushed eastward into New Mexico. Meanwhile, water vapor imagery
reveals a sharp meridional delineation between moist air across
eastern Arizona and a northwesterly flow transporting drier air
across the Desert Southwest. However, conditions remain quite
moist in the lower levels and surface dewpoints have dropped only
slightly into the upper 40s and lower 50s. Dense fog was observed
this morning, mainly across the Imperial Valley though spots as
far east as Phoenix saw reduced visibilities. Clouds have been
prevalent for most of the day across Arizona, where several
smaller vortices promoted the early development of mainly closed-
cell cumulus with bases generally below 3500 ft.
Latest ACARS soundings from Phoenix continue to indicate a
building subsidence inversion and with little to no instability,
showers have struggled to form, except where lift has been
enhanced across isolated portions of the higher terrain north and
east of Phoenix. PoPs have consequently been lowered below the NBM
through Sunday morning, which has been somewhat slow to respond
to this trend. The abundant moisture will instead translate into a
threat of low clouds and fog across portions of the area early
Sunday morning.
The development of fog Sunday morning will largely hinge on to
what extent skies clear and the subsequent radiational cooling.
Latest HREF does in fact indicate widespread potential across
portions of the lower deserts. Raw probabilities are generally
around 10-30 percent, though actual odds are in reality a bit
higher, given the favorable antecedent conditions. Any fog that
develops Sunday morning will have the potential to produce
visibilities less than one quarter of a mile along with hazardous
driving conditions.
Model ensembles continue to show little variability through next
week, depicting gradual height rises and a persistent
northwesterly flow with a drying trend. A high amplitude ridge
will likely stretch from the Desert Southwest well northward into
far northwestern Canada by midweek. However, height anomalies will
only peak slightly above normal yielding temperatures initially
near normal followed by a warming trend later in the week. Light
winds and mainly clear skies associated with the ridge will
promote areas of strong radiational cooling, along with the
potential for freezing conditions each morning across portions of
Pinal County, particularly between Arizona City and Casa Grande.
&&
.AVIATION...Updated at 2350Z.
South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
The primary weather concerns through Sunday morning will be
periods of upper end MVFR cigs over the next couple hours, then
the potential for dense fog around the Phoenix metro Sunday
morning. Current west winds are very light (and nearly calm in
some cases), and may become variable at times as ceilings start to
lift and break up over the next couple of hours. Ceilings will
gradually become more scattered through the evening and
potentially clear overnight with the exception of locations on the
far east side of town where very moist air is drawn over higher
terrain.
A greater concern is the potential for areas of dense fog Sunday
morning with at least a 30% chance of IFR or lower flight categories
around the metro. If clouds hold more steady through the night, fog
would be more localized. However, similar historic scenarios along
with hints from numerical guidance suggest more widespread dense fog
with VLIFR flight categories around the metro (particularly at
KIWA). At this time, confidence is moderate with respect to this IFR
or lower outcome, and have continued with the variety of Tempo
groupings with this package.
Southeast California/Southwest Arizona including KIPL and KBLH:
Light and variable winds are expected through the TAF period for
KIPL whereas they will develop a more defined NW component early
Sunday morning at KBLH. Clear skies are expected at both sites
through the TAF period. While there is another chance for shallow
fog to develop Sunday morning, odds of direct impacts to any
given terminal is less than 25% and not included in this TAF
package.
&&
.FIRE WEATHER...
An unsettled and moist weather pattern will exist over the region
through the weekend, and temperatures are expected to remain
slightly below normal levels through the first half of next week.
Additional scattered showers are likely Saturday across the
eastern districts, with accumulations focused along higher terrain
areas. Nearly saturated conditions will be common over the weekend
with humidity levels generally not falling below 60%. Drier weather
returns next week, however humidity levels should remain above a 25-
35% range. Winds should largely remain below 15 mph through the
period.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
DISCUSSION...Hirsch
AVIATION...Berislavich/18
FIRE WEATHER...Whittock