Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/27/23
Area Forecast Discussion
National Weather Service Corpus Christi TX
544 PM CST Tue Dec 26 2023
...New AVIATION...
.SHORT TERM...
(Tonight through Wednesday night)
Issued at 150 PM CST Tue Dec 26 2023
Key Message:
- chance (25-30%) for temperatures falling below 32 degrees
Wednesday night
High pressure over the region will keep the clouds out of the lower
levels of the atmosphere tonight. The main issue with radiational
cooling will be if the high clouds will contribute to keeping the
temperatures up overnight. To a certain extent, probably, but only
over the southern portions the forecast area and along the Coastal
Bend. Over the region the cooler temperatures will be in the
northern portions of the forecast area with lows around 40 and a 25
percent chance that they will get below 35F. It looks like we
continue to stay in a dry pattern, despite a weak sfc trough that
will move through S Texas on Wednesday. The PWAT values are less
then 0.5" in the forecast area which is below the 25 percentile for
this time of the year, a dry trough passage. There is little to no
temperature gradient behind it, so I hesitate to call it a front.
Relative humidity will be between 20-40% with the high end along the
coastal bend. The winds will be out of the north at less than 10
mph. So no fire issues are expected Wednesday. Wednesday night, with
high pressure, dry conditions, clear skies, and light winds, we get
closer to below freezing. The area around Beeville and Choke Canyon
Lake have 25% chance of 32 or less, so there could be some protected
drainage areas that the temperatures get into the upper 20s.
&&
.LONG TERM...
(Thursday through next Monday)
Issued at 150 PM CST Tue Dec 26 2023
Key Messages:
- 20-40% chance for freezing temperatures Wednesday night
- 50-70% chance for freezing temperatures Thursday and Friday night
- Next chance for rain likely won`t be until next year!
Not much change from the previous forecast package. As high pressure
remains in control for the rest of the week, our next chance for
rain doesn`t appear likely until next year. With the reinforcing
surge of high pressure still expected late this work week, cold
temperatures are expected to flirt with the freezing mark across the
northern Brush Country, northern Coastal Plains and Victoria
Crossroads Wednesday, Thursday and Friday nights, with the best
chances being Thursday and Friday night.
Daytime highs will warm back into the 70s by late this week as
onshore flow returns. However, this warm up will be brief as our
next cold front is expected some time early next week. Looking at
the model consensus for early next week, daytime highs could drop
into the lower to mid 60s behind our next front. Despite the gradual
warm up with onshore flow, overnight lows will remain chilly with
&&
.AVIATION...
(00Z TAFS)
Issued at 544 PM CST Tue Dec 26 2023
Persistent cirrus clouds over the region will be diminishing
by midnight as the upper jet moves to the east. The clouds with
ceilings from 4-6 kft, lingering over the coastal plains, will
also decrease as region of isentropic upglide shifts into the
northwest Gulf of Mexico. With clearing skies and light winds,
there is some concern for radiational fog forming over the inland
coastal plains, mainly over the Victoria Crossroads. Latest RAP
guidance has backed off of fog forecast near VCT and latest SREF
probabilities are still in the single digits for IFR vsbys. Will
keep the TEMPO for MVFR vsbys in fog for VCT and ALI in the 08Z
to 12Z Wednesday time period. Some thin cirrus will move back
into the region by the afternoon. North to northwest winds will
be light as weak high pressure ridge moves into the area for
Wednesday.
&&
.MARINE...
Issued at 150 PM CST Tue Dec 26 2023
Weak over the Gulf is expected Tonight and Wednesday. Isolated to
scattered showers with isolated thunderstorms are expected
offshore. Winds will pick up as a trough moves off the Coastal
Bend, becoming moderate Wednesday night. Waves will build to 3 to
5 feet offshore. The coastal waters will be weak to moderate, with
2 to 3 ft. waves. Weak to moderate northerly flow is expected
Thursday through Friday night, with winds becoming light and
variable Saturday. By Saturday night, winds will shift to the
south and strengthen to 10-20 knots. Rain chances appear slim
until next year.
&&
.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi 48 71 43 65 / 0 0 0 0
Victoria 42 68 37 60 / 0 0 0 0
Laredo 45 70 41 65 / 0 0 0 0
Alice 45 72 39 66 / 0 0 0 0
Rockport 50 71 44 63 / 0 0 0 0
Cotulla 41 71 38 67 / 0 0 0 0
Kingsville 47 71 41 65 / 0 0 0 0
Navy Corpus 55 70 50 63 / 0 0 0 0
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
SHORT TERM...JSL
LONG TERM....JCP
AVIATION...TMT/89
Area Forecast Discussion
National Weather Service Des Moines IA
542 PM CST Tue Dec 26 2023
...Updated for the 00z Aviation Discussion...
.DISCUSSION.../Tonight through Tuesday/
Issued at 334 PM CST Tue Dec 26 2023
Key Messages:
-Snow showers likely (>60%) tonight into Wednesday morning. Rain
will mix in Wednesday afternoon. 1-3 inches of snow possible in
portions of south central and southwest Iowa.
-Rain/snow mix to continue into Thursday with falling high
temperatures to follow through the weekend.
Steep low level lapse rates fueled convective snow showers today
that will continue through sunset. Accumulation has been minor and
focused on grassy surfaces; road temperatures have remained above
freezing today which has helped reduce road impacts. Primary impacts
from these showers will be visibility reductions from the quick
bursts of snow. The convective element will be lost after sunset,
but light snow will continue to fall as an area of QG forcing wraps
around the occluded low in Missouri tonight. Cross sections indicate
a focused area of omega values nearing -15 pivoting around the
eastern half of the low. Combined with theta-e advection from the
south, there will be a peak area of QPF located somewhere in
southern IA or northern MO. 12z HREF guidance along with subsequent
runs of the RAP and HRRR place the highest QPF in portions of
southwest into south central Iowa, yielding 1-3 inches of snow with
locally higher amounts. In coordination with surrounding offices,
have issued a Winter Weather Advisory to account for especially
untreated surfaces during the morning commute on Wednesday. This
advisory may be adjusted in upcoming shifts depending on placement
consensus in guidance.
At the synoptic scale, cold air is being pulled behind the closed
low with the warm conveyor belt (and main moisture tap) getting
wrapped further around the northern part of the system. Theta-e
advection will continue on this northeast current Wednesday
afternoon into Thursday. QG forcing will return again on Thursday
as well, giving additional forcing to especially the eastern half
of the state again. Rain will mix with snow Wednesday afternoon
into Thursday as near-surface temperatures remain above freezing.
After the closed off system slowly migrates east, a clipper system
will drop in from Canada this weekend. Little in the way of
precipitation is expected at this time as moisture doesn`t have a
chance to recover. A certainty with this system`s passing is the
return of seasonal temperatures with highs topping out in the 30s to
end this week and begin the next.
&&
.AVIATION.../For the 00Z TAFS through 00Z Wednesday evening/
Issued at 540 PM CST Tue Dec 26 2023
Scattered to numerous snow showers will continue to impact
ceilings and visibility through the evening and overnight hours,
with the greatest chances for snow being at KDSM and KOTM. As the
system progresses north and east, worsening flight conditions
will increase from the southwest to northeast overnight, creating
MVFR conditions at all sites by tomorrow and a period of IFR
conditions at KDSM and KOTM. Observed ceilings and visibility
will likely be sporadic throughout the forecast period, but TAFs
depict the general conditions and trends through this timeframe.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 3 AM to noon CST Wednesday for
IAZ081>083-092>094.
&&
$$
DISCUSSION...Jimenez
AVIATION...Dodson
Area Forecast Discussion
National Weather Service Grand Rapids MI
634 PM EST Tue Dec 26 2023
LATEST UPDATE...
Update/Aviation
.UPDATE...
Issued at 634 PM EST Tue Dec 26 2023
Bumped up pops slightly due to the surface convergence along the
US-127 corridor. Expect off and on scattered showers (40-60
percent) along this area of convergence tonight with more isolated
showers (20 to 30 percent) to the west.
&&
.SHORT TERM...(This evening through Wednesday night)
Issued at 316 PM EST Tue Dec 26 2023
- Some clearing possible tonight and into Wednesday
Satellite trends in central IL show the clouds scattering out.
HRRR model trends show the low clouds thinning out from southwest
to northeast through parts of the CWA later tonight. Mid to upper
level clouds are shown to persist/increase. This scenario is
supported by the latest SPC HREF model, but they will likely be
scattered to broken. I have featured decreasing cloud cover in
the grids/zones based up on the satellite and models trends. We
should see some sun Wednesday poking through the broken cloud
cover.
- Small risk for freezing drizzle later Wednesday night
The Namnest was showing a short period of freezing drizzle later
Wednesday night. Forecast soundings show unsaturated conditions
above the -2 deg C level 07z in the GRR area with saturated near
freezing conditions below. PTYPE algorithm for this model show
patches of freezing drizzle around. However this appears to be the
only model doing this. Even the SPC HREF is not showing any
freezing rain. Our low temperatures are forecast to drop into the
33 to 37 degree range so for now we will not feature any freezing
rain in the forecast.
.LONG TERM...(Thursday through Tuesday)
Issued at 316 PM EST Tue Dec 26 2023
- Rain Showers Thursday, Possibly Lingering into Friday
A slowly meandering upper low to the south of Michigan on Thursday
will help enforce nearly unidirectional E/NE flow throughout the
atmosphere. Deep layer (1000-500mb) RH will increase from north to
south across the region, which is atypical. Medium range guidance
indicates values of 80-90% RH, though geographic coverage varies
depending on model. 12z GEFS/CMC and the 00z ECE 24 hr 50th
percentile QPF indicate values ~0.10" across the region, with 75th
percentile QPF ~0.25". Not a soaker by any means, but quite damp for
most areas. Some leftover light rain showers could linger into
Friday morning.
- Some Snow Showers Possible New Year`s Eve
Ensemble guidance supports the likelihood of a clipper system moving
through on Sunday (New Year`s Eve) with temperatures cold enough
aloft and at the surface for snow showers. Some or most of this
would occur during daylight hours, and with marginal surface
temperatures in the mid 30s, impacts to travel would probably be
minimal. If snow showers linger into the night (especially closer to
Lake Michigan as flow turns northerly), light accumulations could
occur along with minor travel impacts as temperatures slip below
freezing. Even so, this clipper will have no "staying power" so to
speak, and will be quickly booted out by upstream ridging, common
during El Nino winters.
- Questionable Pattern Heading into Early 2024
Looking into the first week of January, ensemble guidance diverges
with respect to 500mb troughing and 850mb temperatures across the
Great Lakes region. The GEFS and CMC means show greater troughing
and colder temperatures aloft, supporting surface high temperatures
dropping below freezing especially after January 3 with some chances
for lake effect snow. The ECE mean shows less troughing and warmer
air aloft, with mean surface high temperatures above freezing. Until
the long-range guidance settles on a clearer signal, there will
remain uncertainty in pattern evolution during early January.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 634 PM EST Tue Dec 26 2023
Scattered showers are possible mainly along a LAN to MOP line
overnight tonight. IFR to MVFR ceilings are expected as well with
winds gradually becoming more northwesterly overnight. Ceilings
lift to VFR levels mainly along and west of an LDM to GRR to BTL
line Wednesday with lingering MVFR ceilings to the east.
&&
.MARINE...
Issued at 316 PM EST Tue Dec 26 2023
Overall the pressure gradient remains relatively weak through
Wednesday which will act to keep the wind and wave heights below
criteria. The gradient does tighten up on the backside of the
departing storm Thursday. This could result in winds and/waves
making a run at hazardous levels.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...None.
&&
$$
UPDATE...RAH
SHORT TERM...MJS
LONG TERM...Hoving
AVIATION...RAH
MARINE...MJS
AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
837 PM EST Tue Dec 26 2023
.SYNOPSIS...
A large upper level low pressure system will slowly move through
the region over the next several days, bringing repeated rounds
of rainfall and mostly cloudy skies. Temperatures remain
slightly above normal through the end of the working week before
trending cooler over the weekend.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
The 00Z KILN sounding sampled a layer of relatively steep lapse
rates between about 825mb and 550mb. The rain showers that have
developed over the area are the result of elevated forcing, but
have taken somewhat of a convective appearance. There have even
been a few lightning pulses observed (SW Madison County OH near
8PM).
Based on current radar trends and recent HRRR runs, PoPs have
been increased/extended for the eastern half of the ILN forecast
area through the overnight hours, as this activity will likely
continue through most of the overnight -- gradually shifting
west to east as it does.
In the western and southwestern sections of the forecast area,
there have been some breaks in the overcast. Some (but not all)
models are indicating that if enough breaks occur, fog could
develop. This is conditional on the cooling being more prominent
than the drying, as westerly winds are advecting lower dewpoints
into the area as well. Fog will be kept out of the forecast for
now, but the possibility will continue to be evaluated.
Previous discussion >
A large, vertically stacked, low pressure system will be
centered near the Nebraska/Iowa border at the start of the
period with its associated occluded front wrapping spiral-like
around it, stretching all the way out to the Ohio Valley. This
frontal boundary will be stretched north to south through our
area and will continue to incrementally progress eastward.
Rainfall that will have started earlier in the afternoon Tuesday
will continue into the overnight hours. The more robust plume
of PWATS will be in southeastern Ohio/ eastern Kentucky along
the Appalachians as the parent system pulls moisture from the
Gulf/Atlantic coast, resulting in central and eastern Ohio/
Kentucky receiving repeated rounds of rainfall. Areas near the
Tri-State and west may have some sporadic showers, but the
highest QPF footprint (up to 0.75 inch) will be central
Ohio/Kentucky and eastward.
Rain tapers off from west to east during the late night/early
morning hours. Precipitation should stay liquid as the column
stays above freezing, with boundary layer temperatures west of
I-75 only starting to approach the mid/low 30s right around
sunrise. Low temperatures east of here remain in the low
40s/upper 30s.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
The area dries out Wednesday morning as the dry slot of the
parent low pressure system moves into the western Ohio Valley.
This, quite effectively, dries out much of the profile, leaving
only some low level moisture. This translates to a partial
clearing of clouds near the Tri-State Wednesday late morning and
afternoon. Not expecting much more than a few instances of
filtered sunshine, but will be a nice break from the rain.
Our eastern counties (central OH/KY) probably won`t see sun at
all as the occluded front remains in the vicinity, keeping mid
and low level moisture abundant. This cloud deck may
periodically spit out some light rain or drizzle. Daytime high
temperatures reach the mid/upper 40s.
As the closed low slowly pivots into the Mid-Atlantic region,
cannot rule out periods of light rain during the overnight
hours as large scale cyclonic flow/ weak lift and low level
moisture will be present. Overall, anticipating most areas to
remain dry and have just included a slight PoP. Overnight
temperatures fall to the upper 30s in the east, low 30s in the
west.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
A closed low located over southern IL on Thursday will slowly
deepen and become more vertically stacked over western KY by
daybreak Friday. The low will then move east through the state
during the day and eject east-southeast in the evening. As this
occurs, ridging will be found in the Ohio Valley Saturday and
Saturday night with zonal flow on Sunday. Another longwave
trough will extend sw-ne from the Midwest to the northern Great
Lakes Sunday evening. Evolution of this feature beyond the
evening hours is quite varied from one model to another.
Given a relatively cloudy period with little airmass change
through Sunday, temperatures are generally static in the 40s,
dropping into the 30s on Monday and Tuesday. Overnight lows will
run a similar course in the lower 30s through Saturday night,
near 30 Sunday night, and mid 20s to round out the forecast.
There will be a chance for rain through Friday night. Southeast
Indiana could see a brief mix with snow overnight Thursday.
Precipitation should end Friday night for a dry Saturday, then a
low chance of a rain/snow mix is in store for Monday with a dry
Tuesday.
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
Aviation conditions will gradually improve from west-to-east
over the course of the next 6-12 hours.
For KCVG/KLUK/KDAY, generally VFR conditions are expected, with
just a slight chance of some additional rain. There may also be
some MVFR visibilities at KLUK later in the overnight hours,
particularly if there are any breaks in the clouds that could
allow fog to form. Confidence in this occurring is only medium.
For KILN/KCMH/KLCK, a longer period of reduced conditions is
expected, along with a continued chance of rain showers.
Occasional IFR ceilings will occur at KILN for a few hours, and
at the Columbus sites through early morning. MVFR visibilities
are also expected with some of the rain.
Winds will remain under 10 knots through the TAF period.
Generally westerly to northwesterly winds tonight will shift to
the north tomorrow, then become light and variable near the end
of the forecast period.
OUTLOOK...MVFR conditions occasionally expected from late
Wednesday through Saturday morning.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...
NEAR TERM...CA/Hatzos
SHORT TERM...CA
LONG TERM...Franks
AVIATION...Hatzos
Area Forecast Discussion
National Weather Service Marquette MI
715 PM EST Tue Dec 26 2023
.SHORT TERM...(The rest of this afternoon through tonight)
Issued at 148 PM EST TUE DEC 26 2023
Key Messages:
- Areas of fog, locally dense, developing again this evening. Some
improvement possible after midnight.
Early afternoon water vapor shows the sprawling, stacked upper low
centered near Kansas City. This system is so wrapped up that it has
entrained a good deal of midlevel dry air that is currently
advecting into the region from the south. This trend will continue;
however, there continues to be a good deal of low level moisture
trapped near the surface. Expect patchy fog and drizzle to continue
for the remainder of the daylight hours into tonight. Low-level
winds will eventually veer to southerly/southwesterly, which will
gradually advect in a slightly drier and cooler airmass. So, some
improvement in visibility is possible after through the night,
especially after 06Z and near the WI border. A few breaks in the
clouds may even occur, and temperatures may finally drift a couple
degrees below the freezing mark. The highest probability of dense
fog is in the Keweenaw, with HREF probabilities suggesting a >70%
chance of visibilities falling to less than 0.25 miles in the higher
terrain. Dense fog is also possible across portions of the north-
central and east after sunset. Will monitor the need for another
dense fog advisory as trends become clearer this evening. Due to the
cold advection, lows tonight will be lower than recent nights,
mainly ranging through the 30s. However, this is still 15-25F above
normal.
.LONG TERM...(Wednesday through Tuesday)
Issued at 211 PM EST TUE DEC 26 2023
Key Messages:
- Temperatures well above normal to start, though a slow cooling
trend is expected the rest of the week
- Dry after Thursday until this weekend.
- A Clipper moves through this weekend, bringing snowfall mainly to
the north wind snow belts.
While cooler, expect well above normal temperatures to persist
through the rest of this work week as the large, vertically stacked-
low over the Central Plains slowly moves eastward before phasing
with a low over the Eastern Seaboard. As an inverted trough tries to
move into our area Wednesday morning, expect mainly rainfall across
our area. However, over the north central and interior west it is
possible (around 40% chance) that we could see a mix of light
freezing rain, sleet, and/or snow at times. As temperatures warm a
couple of degrees Wednesday, expect only rain with snow possibly
mixing in at times over the highest elevations of the interior west
(near Mt. Arvon and along the Wisconsin border). As the inverted
trough leaves our area Wednesday night, precipitation chances
decrease across the area throughout the overnight hours. However,
some CAMs such as the NAMnest and HRRR are highlighting a small 20
to 30% chance where some upslope showers are possible across the
north central through the overnight hours into Thursday morning,
with spots of freezing drizzle being possible (10 to 20% chance)
over the higher elevations of Marquette and Baraga counties. Any
wintry accumulations that we will receive will be no more than a
trace Wednesday through Thursday morning.
As the low over the Central U.S. continues eastward, it degrades and
phases with a low just off of the East Coast later this week. Thus,
the last of the precipitation associated with the low will be done
by Thursday as ridging builds into the Upper Midwest. While model
blends such as the CONSRaw and NBM keep some residual cloud cover
over the area Thursday, thinking this ridging will finally(!) bring
some sunlight to our area, particularly Friday when the peak of the
ridge aloft moves over us. While temperatures will not be nearly as
warm as it was earlier this week, expect highs and lows to still be
well above normal; the highs Thursday and Friday are projected to be
in the mid 30s to around 40, and lows Thursday and Friday nights in
the 20s.
Moving into this weekend, model guidance is still in agreement that
a Clipper low moves through the Upper Midwest and brings snowfall to
our area, mainly across the north wind snow belts. While delta-Ts
are projected to be only in the mid to upper teens, with some
synoptic help from the Clipper low, there could be enough snowfall
for some nuisance impacts such as dry snow accumulating onto roads
late this weekend into early next week. With temperatures returning
closer to normal with the passage of the Clipper, highs will likely
(70% chance) be closer to the upper 20s around Sunday across the
north wind snow belts.
Moving to the end of the extended period and beyond, model guidance
is suggesting that a ridge over the Western U.S. and Canada early
next week degrades as it attempts to push eastward across the Plains
to our area. As high pressure then reamplifies over the Rockies,
troughing appears to become more dominant over the Upper Midwest as
we head into the rest of next week. This could bring additional snow
chances to the U.P., although some guidance such as the 06z GFS
keeps the polar jet too far north to give us any chance for snow. We
will have a better picture and higher confidence of the pattern in
subsequent forecast packages.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 714 PM EST TUE DEC 26 2023
Flight restrictions persist through this TAF period with ample low
level moisture still in place. Best chances for airport minimums
will be at CMX through the night with little improvement in this TAF
period. Elsewhere, LIFR conditions at SAW could improve through the
night a bit to IFR if some drier air can filter into that area. And,
IWD is currently holding at VFR levels, but will deteriorate to
MVFR/IFR after Wed 09Z.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 211 PM EST TUE DEC 26 2023
Northeasterly gales to 35 knots over the western lake this afternoon
weaken to 20 to 25 knots near the Arrowhead late tonight before
becoming 20 knots or less by noon Wednesday. The calm winds remain
over the lake until cold air advection behind a Clipper low brings
northerly winds of 20 to 25 knots back across the lake late this
weekend. The winds back to the northwest and eventually west next
Monday as the Clipper leaves.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
Dense Fog Advisory until 10 AM EST /9 AM CST/ Wednesday for
MIZ001-003>005-010>013.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Thompson
LONG TERM...TAP
AVIATION...TDUD
MARINE...TAP
Area Forecast Discussion
National Weather Service New York NY
1036 PM EST Tue Dec 26 2023
.SYNOPSIS...
Weakening high pressure will depart to the east tonight. Low
pressure moving up the coast on Wednesday will pass nearby
Thursday morning, move to the east later Thursday through
Friday, and head up into the Canadian Maritimes this weekend. Weak
high pressure will then start to build this weekend and into the
first few days of the new year.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Expanded dense fog advisory to include parts of NE NJ and the
Lower Hudson Valley, as well as NYC. Southern CT and Long Island
remain in the dense fog advisory. HRRR and NAM show expansion
farther north and west throughout tonight with this dense fog.
Still some uncertainty on how far north and west this fog gets
with very little steering flow.
Slightly adjusted temperatures. Not expecting much further drop
in temperature. Upper 30s to lower 40s for lows.
Vsbys will lower once again given plenty of moisture beneath an
H9 inversion and a light onshore flow developing as high
pressure departs to the east.
Rain with the approaching low pressure system should hold off
for the most part, but there could be some areas of drizzle
mainly east of NYC.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
Fog/drizzle will still be ongoing as rain with the frontal
system also move into the area. Siding more with the NAM/ECMWF
idea of the low moving directly up the coast, with its forcing
more directly impacting the area than more out-to-sea model
solutions. Rain is likely from NYC west by midday, the across
the entire CWA by evening, and the rain could become heavy at
times Wed night from late evening into the overnight as the low
moves up the coast, via coupling of jet streaks over New England
and the Mid Atlantic region, also via combo of H7-8
frontogenesis and H8 theta-e advection passing through.
Forecast rain totals from late Wednesday through Wednesday
night range from 1 to 1 1/2 inches, with the higher totals in
the NYC metro area and NE NJ. The 18Z HRRR and 3-km NAM both
suggest higher totals of 2 to 2 1/2 inches may be possible in
this area, and some of the flashier rivers and streams in NE NJ
could surpass minor flooding benchmarks if rainfall leans toward
this scenario. Otherwise, just minor urban and poor drainage
flooding is likely.
The rain will taper off from west to east early Thursday morning.
A consensus of the modeling puts the steadier/heavier rain east
of NYC metro by 12 Thu, and throughout by afternoon. Shower
chances will linger through the day on Thu via combo of weak sfc
troughing lingering in the wake of the departing low, and
organized areas of lift from weak energy ejecting from the upper
low.
Temperatures continue above normal with highs mostly in the
upper 40s and lower 50s.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
An exiting upper level jet streak Thursday night will be
followed by another wider upper level jet streak approaching
Friday into Friday night. Then, the jet streak shifts east of
the area for the weekend. Upper level heights trend from slight
ridging for the rest of the weekend to quasi-zonal flow going
into early next week. Another less wide jet streak potentially
moves across late Sunday into Monday.
The mid level height pattern will remain in a trough across the
region Thursday night through early Saturday with SW flow. A mid
level vorticity maximum moves through Saturday with a
transition to more zonal flow thereafter through early next
week. One embedded shortwave may potentially move across late
Sunday into Monday.
At the surface, low pressure will linger northeast of the region
Thursday night through Friday night. The low eventually moves
through the Canadian Maritimes this weekend. Across the local
region, weak high pressure will start to build in from the west
this weekend and into early next week.
Regarding weather, rain showers will linger around,
intermittent, Thursday night through Friday night. Drier
conditions expected for the weekend and into early next week.
The upper level disturbance may present a few rain and/or snow
showers early next week but probabilities are just slight
chance.
Daytime high temperatures are forecast to exhibit a gradual
cooling trend. Daytime highs Friday are forecast to be in the
mid to upper 40s and by Tuesday, forecast highs range from upper
30s to lower 40s.
&&
.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
IFR or LIFR at all terminals except KSWF which is MVFR. Expect the
low conditions to continue through the morning push and into
the morning hours on Wednesday. Conditions are expected to
improve a little Wednesday afternoon, but only to MVFR for a few
hours before conditions fall back to IFR in rain Wednesday
night.
Winds will be light and variable into this evening, with the winds
going light out of the east late tonight into Wed morning.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Uncertain how much improvement occurs Wednesday afternoon.
OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY...
Wednesday night: Rain with IFR and pockets of LIFR conditions. E-SE
winds G20kt possible late at the coastal terminals.
Thursday: MVFR possible with chance of showers. E winds G20kt
possible in the morning at the CT/Long Island terminals.
Friday: MVFR possible with chance of showers. N / NE winds.
Saturday: Mainly VFR. NW winds G20-25kt.
Sunday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Marine dense fog advy remains in effect for all waters through
Wed morning. E-SE winds increasing Wed night as low pressure
approaches may produce some gusts up to 25 kt on the ern
ocean/Sound waters late Wed night into early Thu morning.
SCA level ocean seas forecast Thursday night and Friday, and
then mainly the eastern ocean waters for Friday night. Ocean SCA
level seas return for much of the weekend. SCA level wind gusts
are forecast mainly across the ocean for the first half of the
weekend.
&&
.HYDROLOGY...
Storm total rainfall 1.0-1.5 inches is likely from Wed afternoon
into Thu morning, with the higher amounts more likely to occur
around and just NW of NYC. Due to recent heavy rainfall and
continued high streamflows, there is a concern for minor
flooding along a few quick responding rivers in NE NJ and
potentially the Lower Hudson Valley. Rainfall of at least
1.5-2.0 inches as depicted by the last couple of cycles of the
ECMWF/NAM as well as the 12Z/18Z HRRR would bring the Saddle
River at Lodi and the Ramapo River at Mahwah above minor flood
stage. Otherwise, minor urban and poor drainage flooding should
be the main hydrologic impact.
&&
.TIDES/COASTAL FLOODING...
The potential remains for minor coastal flood impacts for
vulnerable coastal communities on Thu with a passing low.
The threat exists for mainly the morning high tide,
particularly along the south shore of Nassau and Queens, and
possibly along the SW CT coastline on the Western Sound and NY
Harbor. Tidal departures of 1.25-1.50 ft are needed for minor
flooding, and 2.25-2.50 for moderate flooding during the morning
high tides. About 1 ft additional surge is needed for the
evening high tides.
The threat for dune erosion appears to be low and isolated with
this event.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Dense Fog Advisory until 11 AM EST Wednesday for CTZ005>012.
NY...Dense Fog Advisory until 11 AM EST Wednesday for NYZ069>075-
078>081-176>179.
NJ...Dense Fog Advisory until 11 AM EST Wednesday for NJZ006-104-
106-108.
MARINE...Dense Fog Advisory until noon EST Wednesday for ANZ331-332-335-
338-340-345-350-353-355.
&&
$$
SYNOPSIS...BG/JM
NEAR TERM...BG/JM
SHORT TERM...BG
LONG TERM...JM
AVIATION...BC
MARINE...BG/JM
HYDROLOGY...BG/JM
TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service Pocatello ID
207 PM MST Tue Dec 26 2023
.SHORT TERM...THIS AFTERNOON THROUGH WEDNESDAY NIGHT...
Light snow is pushing eastward from the eastern Magic Valley and
Wood River Valley into the Arco Desert and Lower Snake Plain as
forecast, in association with a weakening shortwave trough. Hourly,
high-res models continue to support this precip "washing
out"/largely vanishing as it reaches the I-15 corridor (so almost
nothing falling out of the sky east of there), with total
accumulations of a dusting to 1 inch of most areas west of Dubois
and Pocatello. While this isn`t much snow, both air and roadway
temperatures remain cold, and very slick conditions are being noted
in parts of the ern Magic Valley and Central Mntns with a multi-
vehicle crash on I-84 west of Burley, so motorists still need to be
prepared to slow down and practice safe winter driving strategies!
Widespread fog is again NOT expected tonight, but given no major
pattern change and recent precip for some, have again been generous
with mention of just patchy freezing fog into Wed AM, especially in
valleys and plains across the ern Central Mntns down across the ern
Magic Valley/lower Snake Plain and srn highlands (targeting where
snow fell today combined with the latest HRRR inclinations). Wed we
switch right back to high pressure ridging with breezy ENE winds
forecast in the ern Magic Valley and a mix of sun and clouds
everywhere. A warming trend will also initiate, with highs Wed
reaching the upper 20s to low 30s. 01.
.LONG TERM...THURSDAY THROUGH NEXT TUESDAY...
Thursday and Friday look dry across central and eastern Idaho. We
could still see some very light snow or flurries across portions
of the area earlier Thursday, but the trend is toward washing out
that next "wave" as it crosses the state. We may see the initial
push from the next incoming storm Saturday evening, but that
likely holds off until sometime on New Year`s Eve. All of the
models and cluster forecasts show split flow on Sunday, although
to varying degrees. Better information to trend toward likely
won`t show its ugly head until later in the week unfortunately. By
New Year`s Day, the ECMWF and about 55% of the cluster forecast
call for a strong split and a closed low potentially developing
off the coast of California and Baja. The GFS and the rest of the
clusters favor a weaker split, and a small uptick in the chance of
precipitation to start out 2024. Our Blend of Models fits
perfectly in this scenario as it takes a blend of all ideas and
gives up a lower chance of rain and/or snow during this period.
Temperatures overall are still expected to warm to or just above
average over the next several days. Keyes
&&
.AVIATION...
So far, SUN and BYI have seen the brunt of any snow and reduced
flight rules today. They both have been down to MVFR/IFR through
early afternoon, but should slowly improve as the afternoon wears
on. The models still try and quickly dissipate this band as it
moves east toward PIH, IDA and DIJ. We did push PIH toward MVFR
with VCSH as there is some hint we could see it hold together well
enough to POSSIBLY impact the airport. We were more optimistic
for IDA as it looks like anything that might hold together would
stay south and west. After this band moves east/diminishes, it
does appear lower clouds will move in/develop behind it. We do
have all 5 TAF sites at MVFR later this evening and overnight. SUN
should see any low clouds move out as the northwest wind kicks in
this evening. Keyes
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Tulsa OK
956 PM CST Tue Dec 26 2023
...New SHORT TERM...
.SHORT TERM...
(The rest of tonight)
Issued at 952 PM CST Tue Dec 26 2023
So far this evening, have only seen a few sprinkles with trace
rain amounts from the radar echoes moving across northeast
Oklahoma and northwest Arkansas as low level remain quite dry.
Some very light rain will continue to be possible overnight, with
some very light snow possibly mixing in at times after midnight,
but have lowered the chances for measurable precipitation to 20
percent for the rest of the night. Also adjusted overnight lows up
a bit in some places as clouds help hold temperatures up some.
&&
.LONG TERM...
(Wednesday through Tuesday)
Issued at 135 PM CST Tue Dec 26 2023
The low pressure system is expected to shift east/southeast into
the Ozarks of MO on Wednesday. The EC and HRRR both suggest
potential for scattered snow showers on the back side of the
system over far NW AR during the afternoon and evening. Some very
light accum is possible, mainly on elevated/grassy surfaces. The
upper system is expected to split into two pieces and elongate
west-east by Thursday, with one piece moving east and another
dropping south over the region. Some light flurries can`t be ruled
out during this time, but will not be explicitly mentioned in this
forecast due to low confidence. A quiet forecast and a warming
trend is expected to close out the week and head into the weekend.
A cold front will pass thru dry to start the next week, with some
chance of rain entering the forecast toward late Tuesday.
Lacy
&&
.AVIATION...
(00Z TAFS)
Issued at 516 PM CST Tue Dec 26 2023
VFR cigs will prevail through most of the period, though
an upper low to the north will result in some MVFR cigs
across the NE OK and NW AR sites for the last 6-8 hours
of the TAF period. There may be a few periods of very light
rain mixed with snow across the NW AR sites this evening and
into the overnight hours, though restrictions to vsbys are not
expected with this precipitation.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 30 41 26 42 / 0 0 0 0
FSM 34 41 29 43 / 0 0 0 0
MLC 32 42 26 43 / 0 0 0 0
BVO 28 39 23 42 / 0 0 0 0
FYV 30 34 25 40 / 20 10 0 10
BYV 31 36 29 40 / 20 20 20 10
MKO 31 41 25 41 / 0 0 0 0
MIO 29 37 27 41 / 20 0 0 0
F10 31 41 25 41 / 0 0 0 0
HHW 33 45 27 44 / 0 0 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...None.
AR...None.
&&
$$
SHORT TERM...05
LONG TERM....30
AVIATION...23