Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/24/24
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
917 PM EST Mon Dec 23 2024
.SYNOPSIS...
Dry weather and cold temperatures continue tonight, with strong
high pressure over the region. Weak low pressure off the
southeast coast brings light precipitation to mainly southern
portions of the area Tuesday. Temperatures warm back to near
normal by the middle of the week, with milder weather and a more
unsettled pattern late in the week into next weekend.
&&
.NEAR TERM /THROUGH TUESDAY/...
As of 900 PM EST Monday...
Key Messages:
- Cold and dry conditions continue tonight.
- Ice potential has decreased Tuesday morning, but some patchy
freezing drizzle and/or very light FZRA can`t be completely
ruled out.
This evening, ~1036 mb high pressure is centered off the New
England coast, and extends down into the Mid Atlantic. A weak
disturbance is located well NW of the area over the upper
Midwest, with an inverted sfc trough extending NE along the Gulf
stream off the Carolina coast (from low pressure off the
FL coast).
Mainly clear for most of the area this evening, but an area of
BKN stratoCU has rapidly spread into much of NE NC and far SE
VA. Temperatures have dropped off into the mid to upper 20s for
most, but readings remain warmer near the coast in the far SE
with the cloud cover. Overnight lows will generally not drop too
much from current values, ranging from the low to mid 20s
inland to the upper 20s to lower 30s closer to the coast and
across the southeast (locally at the coast in the SE it will
tend to stay above freezing).
Low pressure develops off the GA/SC coast later tonight into
Tuesday morning and gradually lifts north before sliding out to
see near the NC/SC border later Tuesday afternoon. Light
moisture spreads into far SE portions of the area early Tuesday
morning in advance of the weak low. Pretty much every main
model/CAM have trended slightly drier/ farther south with the
low, bringing less moisture up into the local area, and thr
latest 00Z/24 HRRR continues this trend compared to earlier runs
from this aftn. Very dry air right at and above the surface
will also help to limit precipitation potential, especially
outside of SE VA and NE NC. As a result, the freezing
rain/icing trend has diminished from the previous forecast with
little to no ice accumulation now expected. There is still a
brief window for at least a slight chance of freezing rain
and/or freezing drizzle, mainly across interior northeast NC,
interior SE VA, and into portions of the western Tidewater, from
approximately 5-8 AM. Again, this is not expected to accumulate,
but one should still be mindful of untreated bridges, roadways,
and elevated surfaces, especially if the the precipitation
comes in slightly heavier than forecast. Any freezing rain
threat comes to an end by ~9 AM at the latest as temperatures
warm above freezing. Light rain showers will then be focused
mainly across northeast NC into far southeastern VA, with the
highest chances closer to the Albemarle Sound Tuesday morning
into early afternoon, before the better rain chances shift to
the east and come to an end. Total QPF from this system will be
minimal, with up to 0.10" possible along the Albemarle Sound.
Skies become partly/variably cloudy during the second half of
the day, with high temperatures in the mid to upper 40s (around
50 across the SW).
In addition to the weak coastal low, a weak disturbance will be
passing well to our north tonight into Tuesday AM. This will mainly
bring an increase in cloud cover across the northern half of the
forecast area, but cannot rule out a brief period of wintry mix
across mainly far northern portions of the CWA from Louisa to
the nrn Neck and into Dorchester MD during the mid/late morning
before temperatures warm above freezing.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 220 PM EST Monday...
Key Messages:
- Dry weather for Christmas day and Christmas night.
Drying out with clearing skies Tue night. Lows overnight into
Christmas morning will drop back into the the mid 20s to around
30F for most of the region, with low-mid 30s near the coast in
SE VA/NE NC. By Christmas day high pressure will move just north
of the area bringing back drier weather conditions. With the
high located to the north temperatures will be slightly below
seasonal highs with temperatures rising in the middle 40s inland
and upper 40s along the coast. Overnight, lows will plummet
into the upper 20s and lower 30s under partly cloudy skies. High
pressure will continue to linger over New England Thursday
keeping temperatures relatively the same across the region with
highs in the middle to upper 40s and lows in the upper 20s to
lower 30s.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 220 PM EST Monday...
Key Messages:
- Seasonable temperatures will make a return through the forecast
period.
- Multiple frontal systems will pass through the area bringing
chances of rain.
Latest ensemble guidance continues to show a potent ridge remaining
in control through Friday into Saturday. The high pressure over New
England will keep the region dry under mostly clear skies.
Temperatures will begin to rise with the upper level ridge support
and highs will be in the upper 40s to lower 50s inland and middle
50s across the southeast for Friday. Lows for Friday will only drop
into lower 30s inland and middle to upper 30s along the coast. As
Saturday approaches there is some disagreement in the ensembles. The
CMC has a weaker low pressure system tracking across the the Great
Plains while the GEFS has a stronger system. The strength of this
system will determine if it can weaken the ridge and allow rain to
return to the region. Even though there is disagreement in strength
there is a decent agreement that there could potentially be some
isolated showers along a warm front late Saturday. However, at this
time PoPs for Saturday remain between 15-25%. Highs for Saturday
will be in the middle to upper 50s and lows in the upper 30s to
lower 40s. By the end of the weekend and early next week the
ensembles continue to hint on a negatively titled trough digging
in across the Ohio River Valley. This trough will bring in a
potential low pressure system that will bring in a decent chance of
widespread rain showers across the CWA. Will note that there is a
disagreement in the strength of the trough. With this disagreement
Pops have been capped off at 40% until there is better agreement
within the ensembles. Highs for both Sunday and Monday will be in
the middle to upper 50s. Lows for Sunday are in the lower to middle
40s while Mondays lows will be in the middle to upper 30s.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
As of 700 PM EST Monday...
Mainly VFR conditions are expected at all of the TAF sites
through the 00z/24 forecast period.
BKN stratoCU have already pushed onshore across NE NC and far SE
VA this evening, though CIGs remain VFR (just above 3k ft).
Clouds will continue to thicken overnight across the SE (and
late across the far N as two separate disturbances approach the
area. Moisture increases enough into early Tuesday AM, leading
to the potential for some light rain at ECG after 10Z, with the
best chances from about 12Z-18Z. The low- end rain chances
spread farther north during the morning hours, potentially
impacting ORF and PHF (~20% chance). There is the potential for
some light freezing rain/rain mix at the onset of the precipitation
early Tuesday AM, but this is expected to be farther inland
across interior portions of SE VA and NE NC away from any TAF
sites. MVFR flight restrictions may impact ECG Tue aftn, though
confidence in this scenario remains low and the TAF keeps
conditions VFR at this time. Otherwise, winds shift to the WNW
and then to the N later Tue aftn with the higher chances for
rain shifting off the SE VA and NE NC coast.
Outlook: VFR/dry Wed-Thu as high pressure builds back across
Quebec/New England, ridging into the local area. NE winds will
avg 5-10 kt inland, with 10-15 kt near the coast in SE VA/NE NC.
&&
.MARINE...
As of 215 PM EST Monday...
Key Message:
- Weak low pressure develops offshore and south/southeast of the
area Tuesday, bringing some potential for elevated winds and seas
over the southern coastal waters Tuesday night into Wednesday.
N-NE winds are 5-10 kt across the local waters this afternoon as
high pressure settles over the area. To our south and southeast,
weak low pressure is taking shape just offshore of NC along an
inverted coastal trough. Seas are running 2-3 ft, highest in
the southern waters, while waves in Chesapeake Bay are 1-2 ft or
less. Light winds are expected through tonight as the flow
shifts southerly and then briefly westerly around sunrise
Tuesday. Another area of (weak) low pressure develops later
Tuesday, tracking E-NE south of the area Wednesday. While direct
impacts are unlikely from this low here, the gradient should
tighten sufficiently for N-NNE winds to increase to 10-18 kt on
the coastal waters Tuesday night into Wednesday...perhaps up to
20 kt S of the Cape Charles. Local wind probs for sustained
winds >18 kt are 70-90% in these areas with only 20-30% in the
Chesapeake Bay. Still, winds are largely forecast to remain sub-
SCA. The other aspect to keep an eye on will be the building
seas with the NNE flow. For now, seas are forecast to build to
3-5 ft S of Cape Charles and 3-4 ft further N. Marginal SCAs may
eventually be required for these seas. Waves in the bay also
potentially increase to 2-3 ft. Winds remain NNE for most of
the week, but subside to 10-15 kt beyond Wednesday.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...None.
&&
$$
SYNOPSIS...LKB
NEAR TERM...AJB/LKB
SHORT TERM...HET
LONG TERM...HET
AVIATION...LKB
MARINE...SW
Area Forecast Discussion
National Weather Service La Crosse WI
609 PM CST Mon Dec 23 2024
.KEY MESSAGES...
- Light wintry mix, largely snow, exits eastward through mid-
afternoon. Impacts, while largely minor, will be focused in
west central WI.
- Fog may occur tonight with visibilities potentially (30%)
dropping below 1 mile.
- Warmer weather from mid week into the coming weekend could
lead to some drizzle, fog, and rain, especially the latter
half the week.
&&
.DISCUSSION...
Issued at 140 PM CST Mon Dec 23 2024
THIS AFTERNOON AND TONIGHT - Wintry mix exits
Compared to guidance yesterday, both additional mid-level dry air
and warmer surface temperatures by about 1-3 degrees delayed onset
and reduced coverage/duration of freezing drizzle. Thus, while a
mixture of every precip type was reported this morning, impacts were
limited.
Over the past couple of hours, an area of light snow has
developed in west central Wisconsin, including La Crosse, Black
River Falls, Camp Douglas, New Lisbon, and at times Sparta.
23.16z RAP soundings reflect this outcome fairly well with
saturation through the atmosphere, including to the DGZ, likely
the result of a combination of frozen hydrometeors falling into
the mid-level dry air intrusion and cooling aloft in close
proximity to the approaching upper wave. With modest 850mb
frontogenesis seen around the I-90/94 junction, should continue
to see light to occasionally moderate snow over the next 2-3
hours within portions of the Winter Weather Advisory area. Thus,
while the Winter Weather Advisory was initially issued
yesterday for freezing drizzle potential, will keep it going in
deference to the potential for impacts from light to moderate
snow within the same area.
Tonight, as the upper wave departs, large scale descent should occur
with surface high pressure and concomitant light winds developing.
Given snow cover across the area and additional surface moisture
from this morning, fog and/or low stratus should develop. While
modeled MRi suggests stratus is favored, the fresh additional
moisture from today`s precip does suggest caution in ruling out fog.
Indeed, 23.12z HREF and 23.09z SREF both suggest around a 30% chance
for visibility below 1 mile. Have therefore elected to keep patchy
fog in the forecast across the area.
MID WEEK INTO THE WEEKEND - Milder temperatures with growing
chance for fog, drizzle, and rain.
Upper air pattern across the CONUS gets messy for most of this week
with lots of short wave troughs passing through flow, none of which
look overly strong. How they migrate and possibly merge makes for
some complications but overall no larger impacts to travel in the
offing. Ensembles show a strong signal for long streak of cloudiness
though, that is for sure.
By Christmas, with one wave passing by to the south, we will be
watching a bit stronger of a wave moving out of the desert southwest
into the Southern Plains. Most ensemble members and blends suggest a
decent moisture source ahead of this with a trend towards a wet
finish to the week. Perhaps the good news, unless you are a snow
lover, is the rising heights and abnormally mild air advecting into
the area. This will be especially noted at night later this
week with the warmer air and cloud cover leading to lows some +2
standard deviations. Our lows might be 15 to 20 degrees ABOVE
normal.
The warmer air will play a factor as southwest flow and yet another
wave crossing the Rockies late Thursday tries to merge with the wave
ahead of it. Lift and moisture advection northward could mean
periods of drizzle and fog, with maybe some plain ole` rain going
into the weekend. In fact probabilities already pretty high /70%/
that far out for widespread rain. As it all draws closer, we will
have to watch for subtle terrain temperature differences that
could produce short lived freezing and impacts to holiday
travel. Nothing jumps out at the moment but this is a tricky
time of year when temperatures are flirting with the freezing
mark. Also some hints of a deformation zone as newly emergent
trough passes Saturday night and if air is cold enough, could
see some minor accumulations across northern half of area.
SUNDAY INTO NEXT WEEK - Turning colder with lower than normal
precipitation predictability
From the weekend on model differences really amplify with cluster
analysis leading to wide variability and hence, lower confidence. It
seems like most ensemble members hint at a cooler stretch with a
mean upper trough establishing itself across the middle CONUS to
start the New Year. At first glance this colder push might make
for a more southern storm track and nothing of significance for
our area.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 552 PM CST Mon Dec 23 2024
The snow has exited the local area, however a broad area of
stratus extends back into the Dakotas. Ceilings are mainly MVFR
with a few IFR ceilings and visibilities due to the exiting
snow. Overnight, low level moisture will generally remain in
place, however there are some hints at breaks/ceiling
improvements over parts of central Wisconsin. Surface high
pressure is building in tonight and Tuesday with diminishing
winds and already ceilings are lowering with dense fog
developing from eastern SD into western MN. The HREF has mostly
40 to 50% probabilities of fog 3 mi or less with a few localized
60% and 20-40%. For now, did include MVFR ceilings at
KRST/KLSE. Confidence is low, but could see IFR ceilings with
reduced visibilities. For now did mention the lower
ceilings/visibilities for a time Tuesday morning at KRST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
DISCUSSION...Ferguson/Shea
AVIATION...Zapotocny
Area Forecast Discussion
National Weather Service Caribou ME
1002 PM EST Mon Dec 23 2024
.SYNOPSIS...
Low pressure will approach tonight and track along the coast on
Tuesday. High pressure will slowly build down from the
northwest Wednesday through the end of the week and crest over
the area this weekend.
&&
.NEAR TERM /THROUGH TUESDAY/...
10:00 PM Update (ASB/MS):
Updated temperatures to match current observations, as cloud
cover should prevent temperatures from getting any colder
tonight through the area. Increased QPF values along Washington
county coastline, as CAM models seem to suggest a potential for
some convection to increase precipitation in this area. Could
either be more snow, or potentially graupel if convection is
strong enough. Otherwise, forecast is generally on track.
Previous Discussion:
Challenging Forecast with Hazardous Travel Impacts Expected
Tonight into Christmas Eve.
This evening will feature cloudy skies with a very dry and cold
boundary layer. Winds have shifted SW with moisture advecting
ahead of an approaching positively tilted sharp 500mb trof.
Expecting temperatures to fall this evening into the single
digits north with teens south across the CWA. Winds are
generally light and variable if not calm for much of the night.
Late this evening expecting the boundary layer to moisten up
over the Moosehead Region and North Woods with light snow
developing. A weak surface low pressure along the boundary will
track into Southern Maine and up along the Downeast coast into
Tuesday which will aid in the enhancement of precipitation.
What has changed? Models continue to enhance the strength of
the 500mb trof with stronger area of PVA. The jet stream
increases with upper level divergence enhancing the surface lift
along and north of a developing coastal thermal gradient. In
addition, stronger moisture advection despite this being a
Alberta clipper origin will enhance QPF values compared to what
has been modeled until today`s hi-res CAMs and 12z global
suite.
Timing: Light snow develops from 11PM - 2AM tonight from west
to east. Snow will become moderate at times especially in the
Central Highlands to Downeast Coast into the morning hours. Snow
will taper late morning from the North Woods to around Noon
along I-95 and then not until tomorrow evening for the Downeast.
Snowfall: liquid QPF expected to be around 0.1 inch north, 0.2
to 0.3 inch in the Central Highlands and 0.35 to 0.5 inch for
the Downeast Coast. Modeled soundings show decently moist DGZ
with 30-40kt winds which will prevent the snow being very fluffy
but still decently fluffy expected. There is some hi- res CAMs
showing weak instability in the DGZ suggesting some convective
enhancements possible. This gives us storm totals of 2-4 inches
for Northern and Northeast Aroostook County into Northern
Somerset, Piscataquis and Penobscot Counties. Across the Central
Highlands including Moosehead, Baxter to Houlton then down to
Bangor and Danforth area expecting 4-6 inches. For Interior
Downeast including Route 6 and 9 expecting generally 4-6 inches
with isolated higher amounts up to 7 inches possible. Coastal
Hancock including Route 1 and MDI expecting 4-6 inches then
Coastal Washington including Cutler, Lubec and Eastport
expecting 6-9 inches. It is possible Downeast Maine could see
higher amounts with several hi-res models including 18z HRRR,
HREF, NAM, ICON and RAP showing double digits from Jonesport
eastward. This will be a challenge with how fluffy, warm air
intrusion as the low passes by and the amount of liquid. Opted
for now to hoist Winter Weather Advisories for the Central
Highlands including Greater Bangor area and from Coastal Hancock
to Northern Washington and Southern Aroostook County. Opted to
upgrade to a Winter Storm Warning for Coastal and Central
Washington County due to increased confidence in snowfall totals
over the 6 inch threshold and the potential for higher amounts.
Impacts: Travel! Big holiday travel day is expected with
several roads being impacted including I-95. Conditions will
improve late morning into midday along and NW of I-95. Downeast
expecting impacts to travel all day with slippery roads.
Snowfall will be light and fluffy and with light winds not
expecting any blowing concerns. Tomorrow evening winds may gust
as high as 15mph after the snow ends which could cause some
drifting in open areas.
Temperatures: Highs will be in the upper teens to low 20s
across the north. Mid 20s for the Central Highlands and upper
20s to around 30F for the Downeast coast. It may touch 32-34F
for the immediate shoreline and islands as the low pressure
passes but will drop back below freezing once it passes to the
east.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
As the storm exits Tuesday evening into Wednesday, expect some low
clouds to remain in northerly low level flow. The cold air mass
in place before storm remains entrenched over the area with lows
dropping back into the single digits and teens for Tuesday
night and highs in the 20s Wednesday. Some readings near the
freezing mark may be expected for coastal Downeast.
High pressure at the surface and aloft will remain in control
over area weather through the remainder of the period. A
blocking pattern emerges by late week. Temperatures aloft warm
through the period, but cold air remains trapped under a
steepening inversion. The challenge in the forecast will be
whether stratocumulus persists through the period under the
inversion. Such a development will have a huge impact on low
temperature forecasts. Clearing at night will foster strong
radiational cooling given the fresh snow cover, light winds and
time of year. Lows could drop below zero. On the other hand,
cloud cover could keep lows in the 20s. NBM percentiles reflect
the uncertainty. For now, have taken an optimistic position on
cloud cover after Wednesday and leaned towards a consensus of
guidance on lows.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Although the column warms through the period under the
anomalously strong upper ridge, the coldest nights of the week
may be Thursday night and Friday night with widespread single
digits...and possibly sub zero readings in northern zones. Given
these lows and the time of year, high temperatures will make
little progress with the inversion. Most of the area stays in
the 20s both days other than the Downeast coast where lower 30s
are forecast.
The high slowly breaks down during the weekend into early next
week and a frontal system is expected to approach from the west.
The question will be whether the high breaks down in this
forecast period or hangs on into next year. While the air mass
modifies during the weekend, CAD sets up and any initial precip
later Sunday into Sunday night stands a decent chance of being
freezing rain or sleet even through we have specified snow in
the forecast for now.
Besides timing, the other variables of interest early next week
will be the amount of precipitation and warming. Using a blend
of guidance, we transitioned P-type to rain on Monday with highs
pushing into the mid to upper 30s and staying in the 30s into
Monday night. PoPs were capped below 50 percent Sunday night
through Monday night due to the timing uncertainties.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
NEAR TERM: VFR this evening. Becoming MVFR overnight with IFR
possible especially at southern terms due to vsby. -SN will
develop overnight and spread eastward. IFR/MVFR will become VFR
late tomorrow from SW to NE. Tonight winds light and variable
turning N 5-10kt Tuesday afternoon.
SHORT TERM:
Tuesday night and Wednesday...Predominately MVFR cigs with light
N winds.
Wednesday night into Saturday...Generally VFR with light N
winds. MVFR cigs may hang into Wednesday night, but the trend
should be improving for late week...albeit slowly.
&&
.MARINE...
NEAR TERM: Small Craft Advisory for the Coastal Waters from
midnight tonight till 1PM Tuesday. SW wind gusts up to 30kt are
likely during this time. Seas will be building 3-6ft. Intra-
Coastal waters seas generally 2-4ft with a few gusts up to 25kt
during the day tomorrow.
SHORT TERM: A brief SCA may be needed Tuesday night into
Wednesday with northerly winds gusting to 25 kt. High pressure
builds Wednesday night through the rest of the week with winds
and seas remaining below advisory criteria.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...Winter Weather Advisory until 1 PM EST Tuesday for MEZ005-006-
010-011-015-031.
Winter Weather Advisory from 1 AM to 1 PM EST Tuesday for
MEZ016-029-032.
Winter Storm Warning from 1 AM to 7 PM EST Tuesday for MEZ017-
030.
MARINE...Small Craft Advisory until 1 PM EST Tuesday for ANZ050-051.
&&
$$
Near Term...Brennan/MStrauser/Sinko
Short Term...MCW
Long Term...MCW
Aviation...Brennan/MStrauser/Sinko/MCW
Marine...Brennan/MStrauser/Sinko/MCW
Area Forecast Discussion
National Weather Service Charleston SC
905 PM EST Mon Dec 23 2024
.SYNOPSIS...
An area of low pressure will track northeast off the Carolina
coast through Tuesday. High pressure will settle over the area
on Christmas Day. A broad area of low pressure will approach
from the west late this week, drifting across the region this
weekend.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Despite the weak returns on KCLX, a band of light to locally
moderate rain continues so spread inland across parts of
Southeast South Carolina and Southeast Georgia. The forecast is
mostly in good shape, but the QPF was increased and pops were
raised to 80% across parts of the Savannah Metro Area into
Beaufort County where rain persists and mesonet observations
show locations have received between 0.25 to 0.50" of rain so
far. This band will move slowly north into the Charleston Metro
Area with time so pops were also raised to 80% there.
23/22z surface analysis placed a wedge of high pressure over the
Southeast U.S. with a pronounce coastal trough extending from
off the far northeast Florida coast to offshore of the lower
South Carolina coast. The trough is forecast to sharpen up
overnight as a west-east oriented band of vorticity extending
east from a well-defined vorticity maximum propagating across
eastern Mississippi begins to interact with the trough. The
trough could cut off into weak surface low southeast of
Charleston by daybreak Tuesday, but how organized this low
becomes is unclear. KCLX radar data show a pronounced southwest-
northeast oriented band of light rain and drizzle along the
Georgia coast and extending into the Charleston Metro Area. This
area of enhanced returns is aligned with a modest area of 850
hPa frontogenesis. The rain is expected to intensify a bit later
this evening and overnight as low-level convergence builds
along the lower South Carolina coast in response to a sharpening
of the coastal trough just offshore. There will also likely be
a further enhancement of the 850 hPa frontogenetic zone as the
mid-level vorticity maximum over eastern Mississippi propagates
farther east across the Deep South. The best rain chances look
to remain along the coast and extending into the Charleston Tri-
County area later this evening before diminishing late as the
best forcing shifts into Northeast South Carolina.
Pops from 20-40% inland to the 50-70% at the coast still looks
reasonable, although some slight timing and areal adjustments
were needed for the next several hours to take current radar
trends into account. There was an earlier concern that as some
of the rain that pushes inland could mix with some sleet pellets
at the onset due to diabatic cooling, but RAP forecast soundings
show wet-bulb profiles remaining well above freezing through
the night. So, the risk for sleet seems unlikely at this time.
Lows will range from the mid 30s well inland to the mid 40s at
the beaches.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
Tuesday: Short range models indicate a gradually deepening
coastal low will track NE off the Carolina coast during the
morning. The low is timed to lift north of the NC line by noon.
As the low tracks north, dry air will steadily advance across SE
GA and the SC Lowcountry. Isolated to scattered showers should
come to an end by mid-day, with cloud cover decreasing through
the rest of the day. High temperatures are forecast to range
from the low 60s across SE GA to the low to mid 50s across
Charleston Tri-county. High pressure will build across the
forecast area Tuesday night. Forecast soundings and simulated
satellite indicate mostly clear sky, primarily thin high clouds
across GA. Low temperatures are forecast to range from the mid
30s inland to the upper 30s along the coast.
Christmas Day: The mid-level pattern will feature a shortwave
ridge centered across the region in the morning as a trough
amplifies across the Arklatex. At the sfc, high pressure
centered over New England will remained ridged across region
through the day. Conditions should feature dry weather with
light NE winds. Highs should peak around 60 degrees.
Thursday: Low pressure over the Great Plains is forecast to
organize, lifting a warm front across the Deep South. Cloud
cover is expected to gradually increase from the west. Thursday
should begin with temperatures around 40 degrees warming to
around 60 degrees in the afternoon. Isolated showers are
possible across the outer Atlantic waters, with dry conditions
across SE GA/SC.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Friday: Long term guidance generally indicates that a secondary
ridge will build across the region, with the ridge axis passing
over the region during the afternoon and evening. The sfc ridge
will remain across the forecast area, axis near the east facing
slopes of the Southern Appalachians. Weak isentropic lift may
yield increasing cloud cover across the CWA, isolated to
scattered showers over the coastal areas. High temperatures are
forecast to range between 60 to 65 degrees.
Saturday and Sunday: A cold front will approach from the west,
resulting in strengthening return flow across the forecast area.
Weak synoptic scale forcing and building moisture may support
isolated to scattered showers. Temperatures will remain around
10 degrees above normal. Low temperatures are forecast to range
around 50 degrees on Saturday to the mid 50s on Sunday morning.
High temperatures are forecast to generally range between 70 to
75.
Monday: A cold front may push over the forecast area, then
stalling along the coast. Conditions should gradually dry from
the west through the day. Temperatures are forecast to begin the
day around 50 degrees with highs around 70 degrees.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
24/00Z TAF Discussion:
KCHS/KJZI: Slight rain and drizzle will quickly spread into both
terminals this evening as weak low pressure tries to develop
offshore. Light rain will pick up in intensity later overnight
with MVFR vsbys in RA and BR peaking 04-07z. Observations along
the Georgia coast into far southern South Carolina suggest vsbys
could drop as low as 2-3SM, which will most likely impact KJZI.
TEMPO groups were used at both terminals to try and capture the
heaviest conditions. MVFR cigs will linger overnight, returning
to VFR by early afternoon as clouds begin to scour out as low
pressure exits the area.
KSAV: Light rain and drizzle will impact the terminal this
evening as low pressure begins to organize offshore. MVFR cigs
will linger for much of the night before scouring out after
daybreak as low pressure begins to exit the area.
Extended Aviation Outlook: VFR.
&&
.MARINE...
Tonight: A 1020-1021 mb low will form over the Gulf Stream off
the northeast Florida coast early on, then lifts north-northeast
to a position about 175 nm east of Savannah by morning. About a
3-4 millibar gradient will exist between an inland wedge and
the developing low, allowing for solid Small Craft Advisories
for all Atlantic waters. Winds start the night N-NE as high as
20-25 kt, with gusts near 30 kt. There will even be a few gusts
near Gale Force as a 35-40 kt low level jet moves through early
on. But any such winds are too isolated and/or infrequent to
raise a Gale Warning. Winds back a bit more to the N and NNW
late as the low gains latitude, and speeds do drop off a little
behind the low level jet. Seas will average 5 to 7 feet, except
for up to 8 feet on the outer Georgia waters. Winds in
Charleston Harbor will start off NE around 15 kt, then back more
N at 10-15 kt late.
While light to moderate rains will be common throughout, there
will also be a risk for a few t-storms. This is mainly on the
South Carolina waters and parts of the Georgia waters out beyond
20 nm from shore. There might be just enough instability
(either elevated or surface based) for isolated t-storms to
occur.
Tuesday: A coastal low will track northeast away from the
marine zones through the period. Gusty northwest winds will
remain across the coastal waters during the morning, veering
from the northeast during the night. Seas are forecast to begin
the day between 4 to 7 ft, decreasing to 3 to 5 ft during the
evening. Small Craft Advisories will remain across the
Charleston County nearshore waters and outer GA waters through
most of the day, then ending in the evening.
Christmas: High pressure will build across the region,
supporting northeast winds between 15 to 20 kts. Seas are
forecast to range from 3 to 5 ft.
Wednesday Night through Saturday: A sfc ridge will remain
across the coastal waters during the period, speeds generally
between 15 to 20 kts. Wednesday night into Thursday, winds may
surge to around 25 kts. As a result, seas are forecast to build
3 to 5 ft across the nearshore, with 6 to 7 ft across the outer
GA waters. A Small Craft Advisory may become necessary for the
outer GA waters on Thursday. Otherwise, conditions appear to
remain below Small Craft Advisory criteria.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory until 8 PM EST Tuesday for AMZ350.
Small Craft Advisory until 1 PM EST Tuesday for AMZ352.
Small Craft Advisory until 7 AM EST Tuesday for AMZ354.
Small Craft Advisory until 2 AM EST Wednesday for AMZ374.
&&
$$
Area Forecast Discussion
National Weather Service Grand Forks ND
951 PM CST Mon Dec 23 2024
.KEY MESSAGES...
- Extended period of fog forecast through at least Wednesday,
some of which will be dense.
- Above average temperatures mid to late week will bring chance
for light rain or wintry mix between Friday and Saturday.
&&
.UPDATE...
Issued at 950 PM CST Mon Dec 23 2024
Fog continues to expand across the region this evening. This
will continue through the overnight period into tomorrow. Not
much has changed in confidence on ending time, so the Dense Fog
Advisory will continue through at least 18z.
UPDATE
Issued at 646 PM CST Mon Dec 23 2024
The Dense Fog Advisory has been expanded to last through 18z
tomorrow and includes the entire CWA. Fog will continue to
expand overnight tonight, encompassing a majority of eastern
North Dakota and northwest Minnesota. While there is the
potential for fog to continue after 18z, the probability for
this is low due to increasing wind speeds. Confidence will
increase in if we can end the Dense Fog Advisory as we get
closer to noon tomorrow.
&&
.DISCUSSION...
Issued at 200 PM CST Mon Dec 23 2024
...Synopsis...
Following yesterday`s shortwave trough, shortwave upper ridging
over the Dakotas into Minnesota is readily seen on water vapor
satellite imagery this afternoon. Underneath this ridging,
surface high pressure has settled into the area. As upper
ridging continues to slowly propagate east, surface high
pressure will also slide east into Minnesota and Wisconsin by
Wednesday. Within this surface high pressure, trapped low level
moisture is promoting heaping low stratus clouds and fog, some
of which continues to be dense. Brief incidences of very light
snow and/or freezing mist have also been observed or reported
across the area.
While the surface high and accompanying fog/stratus gradually
shifts east, a couple of weak shortwave troughs move out of the
Northern Rockies through Wednesday. Overall, these troughs are
devoid of deeper moisture for precipitation. However driving the
troughs is strong Pacific jet nosing into the Northern Rockies.
This will promote chinook winds warming temperatures aloft and
eventually advecting into our area. This will contribute to
above average temperatures into the 20s and 30s. Relatively
higher surface dew points will also advect over the region. This
warm/moist advection along with increasing low level winds will
promote advection fog processes, especially given snowpack over
our area. This lends higher confidence in an extended period of
fog through at least Wednesday, possibly beyond. More details
on this along with potentially unique but low probability
hazards can be found below.
Emanating out of the Pacific jet will be split flow starting
over the West. One feature is suggested to be a deeply digging
upper trough into the Great Basin that may cut off as it enters
the Southern Plains. Quasi-southwest flow with embedded upper
ridging into the Northern Plains north of this deep trough/cutoff
low between Wednesday and Friday. This conceptually favors
freezing drizzle for our region, which remains a possibility.
Not much evidence in probabilities offered by ensemble guidance
just yet in this occurring, so this is purely just based on
pattern recognition based on climatology.
Most ensemble guidance eventually swings the deep trough/cutoff
low into the Upper Midwest between Friday and Saturday. There
may also be smaller, secondary upper waves moving out of
Northern Plains into the Northern Plains as this occurs or
shortly afterwards, which makes sense given the split flow
precluding this occurrence. These features offer the chance for
precipitation into our area, including the potential for rain
and/or wintry mix. As of now overall amounts look to be light
without more robust/consolidated forcing into our area, but
with temperatures near the freezing mark and liquid
precipitation possible, this could be bring impacts from icing.
It is much too early to put confidence in temperature regime
that would dictate precipitation type, influencing potential for
impacts. Additionally, ensembles still differ in synoptic
evolution of the deep trough/cutoff low as well as its
interaction with secondary waves as they mingle within the
Northern Plains into Upper Midwest late this week.
...Extended period of fog; potential impacts from accumulating
frost...
The weather pattern through at least Wednesday offers higher
than average confidence in fog into our area, particularly
during tomorrow into Wednesday from advection fog processes over
our current cold ground/snowpack. While exact details in timing
and location of dense fog remains in question, the chance for
extended periods of dense fog through Wednesday as offered by
guidance like HREF and HRRR is around 40%.
This extended period of dense fog amid freezing temperatures
will continue to promote rime ice/hoar frost accumulation on
exposed objects, including power lines. This may introduce
potential impacts to power infrastructure should large
accumulation of frost continue onto power lines. Accumulation of
frost weighing down power lines is already being observed this
afternoon on NDDOT webcam west of Cavalier.
From a historical perspective, power-related impacts from frost
accumulation isn`t uncommon in North Dakota. However, details
on how much accumulation or duration of dense freezing fog that
typically lead to these impacts remains uncertain.
Adding an additional layer of uncertainty is a period of
increased winds tonight into Tuesday between 10-20 mph. This may
be enough to help knock down frost accumulations, but again
confidence is low if this will be strong enough wind. Should
wind be strong enough to knock down frost accretion, the chance
for impacts markedly goes down. We should know if this has
occurred by late Tuesday or Wednesday.
Yet another additional layer of uncertainty is how potential
freezing drizzle between Wednesday and Friday may play into
this. Previous events of long duration freezing fog leading to
large frost accumulation followed by light rain/drizzle has led
large impacts from power outages, notably in western ND in 2009.
Confidence in freezing drizzle to occur in our area should
increase around midweek.
While the chance of impacts to power infrastructure/power
outages this week is low (less than 10%), the potential for this
to cause high impacts in a somewhat unique fashion surrounding
the holiday timeframe is worth the messaging opportunity.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 512 PM CST Mon Dec 23 2024
TAFs will be at least IFR through at least 12z tomorrow. The
primary issue will be fog that appears likely to continue to
spread overnight tonight. Signals diverge on when fog will
dissipate, with about half of guidance pushing it away at 18z.
Confidence is low in this occurring, so for now the 00z TAFs
will be fairly pessimistic. There may be brief breaks in between
of MVFR or VFR, but expect it to remain predominately IFR.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Dense Fog Advisory until noon CST Tuesday for NDZ006>008-
014>016-024-026>030-038-039-049-052>054.
MN...Dense Fog Advisory until noon CST Tuesday for MNZ001>004-007-
029.
Dense Fog Advisory until noon CST Tuesday for MNZ005-006-008-
009-013>017-022>024-027-028-030>032-040.
&&
$$
UPDATE...Perroux
DISCUSSION...CJ
AVIATION...Perroux
Area Forecast Discussion
National Weather Service Hastings NE
557 PM CST Mon Dec 23 2024
.KEY MESSAGES...
- Areas of fog and freezing fog will be possible overnight and
a dense fog advisory goes into effect for portions of south
central Nebraska at 11 PM this evening.
- A second round of fog is possible Christmas Eve night into
Christmas morning. Some of this fog could once again be
dense.
- A small chance for precipitation (20-40%) returns to parts of
the local area Thursday and Friday. Most of this precip should
fall as rain, with overall precipitation totals likely ranging
from only a few hundredths to around a tenth of an inch of
rain.
- A modest warm-up is in store for next weekend with widespread
high temperatures in the 50s (Fri-Mon).
&&
.DISCUSSION...
Issued at 215 PM CST Mon Dec 23 2024
Mostly cloudy skies and mild temperatures persisted across the
local area for much of the day. Clear skies to our north should
gradually work their way south toward the NE/KS state line by
dark or shortly thereafter, and this clearing should allow
temperatures to fall off fairly rapidly during the evening
hours. As temperatures fall and very light southeasterly winds
return, expect the potential for fog development across much of
the local area overnight. Model signals for dense fog
development overnight are fairly strong, and went ahead and
issued a dense fog advisory for much of the area starting at 11
PM this evening. Given sub-freezing temperatures also in the
forecast overnight, this dense fog could freeze on elevated and
untreated surfaces, making for a potentially slick start to the
day on Tuesday in spots.
As a back door cold front tracks southwest into the local area
on Tuesday, expect temperatures to only climb into the 40s, or
about 10 degrees below this afternoons high temperatures.
Thereafter...the 18Z run of the HRRR as well as SREF probs are
indicating a possible repeat of dense fog across the local area
Tuesday evening into Christmas day, and given another night of
mostly clear skies, light southeasterly flow and elevated
dewpoints - this seems reasonable.
The next system, which will be around the four corners region on
Christmas day, is expected to emerge into the Plains on Thursday
and Friday, bringing a chance for some light precip back to the
local area. While the NAM looks very drizzly in nature with
this system, kept the precip type as light rain for both
Thursday and Friday. Either way, precip totals will be light,
and likely all liquid, so minimal impacts are expected Thursday
and Friday.
Temperatures should then warm back up to well above normal over
the weekend (50s!) as a transitory ridge of high pressure scoots
across the plains. This dry and warmer than average weather will
then persist into early next week with another small chance of
precip Monday returning Monday afternoon or evening.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 544 PM CST Mon Dec 23 2024
For KGRI/KEAR Airports:
The primary aviation concern will center around the probability
for fog including dense (<1/4SM) fog. The SREF probabilities for
visibilities less than 1 mile get as high as 50-60%. Recent HRRR
runs are the most aggressive with the dense fog and continue to
indicate widespread less than 1/4SM visibility in fog mainly
after midnight through as late as noon. The probability for
dense fog is high enough that a dense fog advisory was issued
for both KEAR and KGRI from midnight through 10 AM, but it`s
possible that the dense fog could last longer than 10 AM and the
dense fog advisory may need to be extended in some areas
through 11 AM or noon. The fog is not expected to last all day
and we expect to see a return to VFR conditions during the
afternoon hours. The wind will remain light and variable to
generally southeasterly throughout the TAF valid period at less
than 10 mph.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...Dense Fog Advisory from 11 PM this evening to 10 AM CST
Tuesday for NEZ039>041-046>049-061>064-074>077-085>087.
KS...None.
&&
$$
DISCUSSION...Rossi
AVIATION...Wesely
Area Forecast Discussion
National Weather Service North Platte NE
916 PM CST Mon Dec 23 2024
.KEY MESSAGES...
- Dense Fog Advisory in effect later tonight until 10 AM CST for
Boyd, Holt, Garfield and Wheeler County.
- Above average temperatures expected to persist the next 7 days
across all of western and north central Nebraska.
- The next shot a precipitation arrives Wednesday night and
again Thursday night into Friday, though confidence remains
low (10-30%) at this time. Any precipitation looks to
primarily fall in the form of rain.
- A return of dry conditions with above average temperatures
(50s) is expected into next weekend. This could also lead to
the return of increasing fire weather concerns.
&&
.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 310 PM CST Mon Dec 23 2024
The short term concern will be the development of fog across the
east after midnight tonight lasting until 16Z Tuesday. This is
in close agreement with the latest HRRR and RAP13 as well as the
HREF grand ensemble with probabilities of less than a half mile
up to 70 percent. This will mainly affect Boyd, Holt, Garfield
and Wheeler Counties, where a Dense Fog Advisory is in effect
from 06Z tonight until 16Z Tuesday.
Tonight, surface high pressure will remain centered by MN into
WI overnight. Surface winds across western Nebraska will be
light at 5 mph or less, with a southerly component. Lows will
again be above normal from 25 to 30 across the area.
Tuesday, an amplified upper ridge over the Central Rockies will
build into the High Plains in the afternoon. This will bring
another mild day, with highs 50 to 55 across the west, to the
mid 40s over the far eastern zones. After morning fog and
stratus lift in the morning, sunny skies are expected in the
afternoon.
Tuesday night, the transitory upper ridge will move over the
region, as an upper trough moves across the Great Basin with a
closed low forecast to develop at the base of the trough over
northern AZ by late Tuesday night. Lows again remain above
normal from 25 to 30. Could see fog development after midnight
near and south of Highway 2 and 91 (see further details below).
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 310 PM CST Mon Dec 23 2024
The upper low over the Four Corners Region on Wednesday will be
a primary feature Wednesday night into Thursday. Confidence
continues to increase that this upper low ejecting across the
southern Plains Wednesday night into Thursday afternoon will
largely affect Kansas and areas to the south. With a weaker low
and southerly track, confidence has increased in lesser
precipitation chances locally with this initial system.
Probabilities of >0.1" of precipitation accumulation has
dropped to just 5% or less for portions of southwest Nebraska.
This is only for Wednesday night. Soundings support any
precipitation falling as rain. The NBM probability of fog with
visibilities below 5 miles are 30 to 50 percent, near and south
of Highway 2 and 91. Therefore, fog potential is increasing for
Wednesday (Christmas morning). Highs Wednesday and Thursday will
continue to remain above normal from the mid 40s to near 50.
Thursday night and Friday, the downstream trough and closed low
is forecast to become an open trough as it moves across MO into
IL. Upstream, a northern stream trough across the Rockies will
cross Nebraska and Kansas. NBM probabilities of >0.1" is only 10
to 20 percent across the southeastern half of the area. If any
precipitation does occur, it should fall mainly as rain.
A flattened upper ridge will build into the region thorugh
Sunday. Dry conditions quickly return, and increasing warm
advection should push highs into the 50s. With the return of
warm and dry conditions, will have to monitor for increasing
fire weather concerns. Medium range models show the potential
for a stronger cold front moving in next Monday (Dec. 30th) and
the introduction for POPS in the form of rain or snow showers.
Current highs are 45 to 55, with the potential for colder
temperatures to be felt.
&&
.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 914 PM CST Mon Dec 23 2024
A mid-level cloud deck will linger across southwest Nebraska
through most of tonight with VFR conditions expected. Mainly
clear skies are expected across the Sandhills and portions of
north central Nebraska with VFR prevailing. Eastern portions of
north central Nebraska around ONL will see low ceilings (IFR and
local LIFR) lingering into Tuesday morning. Winds will be light
area wide, generally less than 10 kts.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 10 AM CST Tuesday for NEZ007-010-028-
029.
&&
$$
SHORT TERM...Roberg
LONG TERM...Roberg
AVIATION...Taylor
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
541 PM CST Mon Dec 23 2024
.KEY MESSAGES...
- Multiple rounds of rain are expected during the holiday week,
with the best chances (60-100%) late Tuesday/Tuesday night
across portions of east central and southeast Missouri as well
as south- central Illinois.
- Above normal temperatures are forecast for the entirety of the
holiday week, with the warmest temperatures forecast Friday
through Sunday with highs well into the 50s each afternoon.
&&
.SHORT TERM... (Through Late Tuesday Night)
Issued at 137 PM CST Mon Dec 23 2024
A surface cold front is currently draped from near KMCI>>KUIN as of
1900 UTC. This front is expected to continue to sag southward
through tonight, become more ill defined, and then stall out across
southeast Missouri and southwest Illinois. Ahead of this front,
broad/weak low-level moisture convergence has helped lead to
scattered sprinkles/very light rain showers across parts of
southeast Missouri and southwest Illinois. This activity is expected
to continue sliding southeastward through the evening.
A push toward more widespread, stratiform light rain is still
expected late tonight as low-level moisture convergence strengthens
coincident with increasing mid/upper level forcing for ascent
downstream of an approaching trough. This steady light rain is
expected to reach parts of southeast Missouri just before daybreak
on Tuesday, and then spread gradually east and north through the
day. By late afternoon, the northwestern edge of the precipitation
shield is expected to be reach roughly a Jefferson City to Troy, MO
line. There remains some uncertainty as to how far northwest this
steadier light rain gets, with the 9Z RAP and 12Z HRRR about 50-75
miles further south/southeast than this forecast. However, all lower
resolution guidance as well as the remaining CAMs are quite a bit
further northwest so leaned on the consensus here. That being said,
the highest confidence in rain is in parts of southeast Missouri and
southwest Illinois where 80-100% PoPs exist late Tuesday afternoon
through much of Tuesday night.
Total rainfall amounts continue to look fairly light overall, with
the HREF LPMM only having a small area right around 0.50" in
southeast Missouri. While the duration of the rain may be fairly
long (18+ hours possibly), the rates look very light. This makes
sense given very weak forcing for ascent at mid/upper levels of the
atmosphere.
Temperatures will remain on the mild side, mainly at night given the
persistent low stratus and weak temperature advection regime
expected to be in place through the short-term forecast period. Lows
both tonight and Tuesday night are expected to be in the 30s to low
40s from north to south, or about 10 to as much as 15 degrees above
normal for late December. Highs on Tuesday will not rebound much,
likely only rising about 5-8 degrees due to the low clouds and
incoming rain from the south. Highs are forecast to be in the low to
mid 40s, just a few degrees above normal.
Gosselin
&&
.LONG TERM... (Wednesday through Next Monday)
Issued at 137 PM CST Mon Dec 23 2024
(Christmas Day - Thursday)
Steady light rain looks to end by Christmas morning as stronger low-
level moisture advection moves out of the area. In addition, the
track of the midlevel shortwave trough has trended quite a bit
further to the south, leaving the mid-Mississippi Valley more within
a shear axis than anything. This is a long way of saying that
rainfall activity on Christmas Day looks more unorganized and very
light. The best chances (30-50%) are mainly in eastern Missouri and
over into Illinois beneath this shear axis and within broad, weak
surface convergence along an inverted trough.
Christmas night into Thursday should largely be dry, though there
may be some patchy drizzle hanging around. The setup appears
favorable, with weak surface convergence, low stratus, and dry
midlevels of the atmosphere. Deterministic model guidance also has
some splotchy very light QPF - another sign pointing to the chance
of drizzle. Did not add to the forecast quite yet, but this is
something that may need to be added in future forecast updates.
Regardless of any drizzle though, the gloomy look and feel will
continue with thick, low stratus draped across the area. Similar to
earlier in the week, this will really help limit the temperature
fall Christmas night and climb each day. Lows around 40 degrees are
likely Christmas night, with highs moderating a bit by Thursday into
the low to mid 50s. Highs have been trending downward however
through midweek and there appears to be room for Thursday`s highs to
come down further as we get closer.
(Thursday Night - Next Monday)
The active pattern continues late this week heading into the weekend
as two more distinct midlevel shortwaves look to quickly pass
through the region. Each of which still has a fair amount of
uncertainty with them in terms of track/timing/uncertainty, which is
not too surprising given the very short wavelengths between each
successive wave. While the details will need to be pinned down over
the coming days, there appears to be two main windows for rain to
impact the parts if not most of the area: late Thursday night/Friday
and Saturday/Saturday night. There is more confidence in late
Thursday night/Friday, with 80-90+% of LREF members showing
measurable rainfall. Compare that to the Saturday/Saturday night
time period, where only 40-65% of members have measurable rain.
Looking at temperatures, there remains very high confidence in well-
above normal readings through this weekend and into early next week.
Highs are likely to be well into the 50s Friday through Sunday, with
some locations potentially even making a run at 60 degrees if there
is any sunshine that occurs. Lows are forecast to be mainly in the
mid to upper 40s. To put those numbers in perspective, those lows
are likely to be above normal highs for the period.
Gosselin
&&
.AVIATION... (For the 00z TAFs through 00z Tuesday Evening)
Issued at 531 PM CST Mon Dec 23 2024
Sprinkles continue to push across the area with little to no
impact at the terminals and a dry forecast will largely continue
through the evening. Overnight MVFR ceilings will converge on the
terminals from the north and the south. The southern deck is
already impacting COU and will slowly move northward overnight,
impacting JEF. The northern deck is currently across Iowa and will
slide southward overnight, finally impacting UIN during the early
morning hours. Increasing low-level moisture from both sides
will help to lower ceilings but may also result in decreased
visibility.
A minor improvement in visibility and ceilings could occur during
the morning and early afternoon hours tomorrow ahead of the next
chance of rain. Rain will move into the St. Louis metro terminals
tomorrow afternoon bringing reduced visibilities and eventually
IFR ceilings to the area. Again, low-level moisture is expected to
be significant, increasing confidence in IFR ceilings and MVFR
visibility. Given the signal, I`ve gone ahead and included a
mention of this in the TAF. What is a little more uncertain is the
exact timing of this reduction in flight conditions as well as the
severity. This will be further refined with future forecasts.
Confidence is lower that rain will move into the mid-Missouri
terminals, so for now have left mention of it and the lower
ceilings and visibility out of the TAF for now.
Winds will become light overnight and eventually swing around to
the northeast as a cold front drops through the forecast area
overnight.
Delia
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX