Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/09/22
Area Forecast Discussion
National Weather Service Binghamton NY
917 PM EST Sat Jan 8 2022
.SYNOPSIS...
A storm system brings a wintry mix late tonight into Sunday.
Most areas will see a mix of freezing rain and sleet, with some
snow mixed in early. Precipitation will change to scattered rain
and snow showers in afternoon. Significant lake effect snow
will set up mainly north of the Thruway Sunday night into
Monday, followed by a blast of Arctic air for the whole region.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
915 PM Update...
Winter Weather Advisory start time for Central Southern Tier-
Finger Lakes-Syracuse areas has been moved up to 3 AM. Initial
radar echoes will be virga or perhaps sleet with dry low level
air that has to be overcome, but then possible freezing rain
sooner than had previously been forecast. This faster apparent
evolution is not too surprising considering the abrupt warm air
advection/strong southwest flow aloft; it is typical for the
models to have to play catch up for this type of situation.
Also, remainder of Winter Weather Advisory for Northeast PA and
in NY from Tioga-Cortland-Madison east, now has end time out to
4 PM Sunday since higher terrain will still be vulnerable to
freezing rain into the afternoon, albeit light. With Arctic air
visiting today, just prior to the event, ground temperatures are
quite cold. Even as air temperatures creep above freezing
midday-early afternoon, there may be lingering additional light
ice accretion on untreated ground-based surfaces.
As expected, the initially clear sky and very low dewpoints are
promoting good radiational cooling this early evening;
temperatures are in teens-mid 20s. However, there will be a
limit to that with increasing south-southwesterly flow already
getting underway just above the surface, and inbound clouds now
over western PA- NY which are quickly spreading east.
Temperatures will mostly creep up overnight.
Previous discussion...
Steep isentropic lift and slow top-down moistening of the
column will result in a lot of virga to start off, which
consequently will help keep the boundary layer cool via
evaporational cooling. Precip will first reach the ground closer
to 09-10Z, becoming more widespread towards dawn as upper level
lift increases in response to strong divergence in aloft.
Model QPF is still generally focused across the Upper
Susquehanna headwaters, Catskills, and Poconos, as well as along
and north of the Thruway in an area of steeper isentropic lift,
and also at the nose of the strongest low level winds aloft.
Lighter precip is likely across the Finger Lakes due to
downsloping off the Allegheny Plateau. Still seeing large
differences in QPF maximums, with the 12Z GFS and NAM showing
the widest differences near and north of the Thruway (0.50-0.60
storm total QPF on the GFS, over 1 inch on the NAM). NAM appears
to be too quick in developing accumulating precip with the dry
airmass, and overall too wet later in the day. Basically went
with a mix of WPC Guidance with WRF ARW and 12Z HRRR which are
which provide some orographic details.
Forecast soundings look to waver between sleet and freezing
rain for much of the area as the strength of the warm nose
varies (and may weaken with evaporative cooling), and the depth
of the near-surface freezing layer may be significant at first,
but slowly erode. Expect sleet will eat into the freezing rain
totals significantly in places, but it`s going to be highly
variable across the area. NBM ensemble p-type methods were
trying to put too many eggs solidly in the sleet basket over
freezing rain, resulting in extremely low ice accumulation.
Instead we took a more balanced approach, applying 50-70 percent
of mixed QPF to freezing rain accumulation. Result is broadly
similar to WPC guidance, but with localized amounts a little
higher, especially over the Susquehanna headwaters and Thruway
corridor. Max amounts look to be just under 0.25 inches. A
little concerned that some pockets of heavier amounts could
develop, particularly in the area north of I-88 and up into the
Mohawk Valley (but east of SYR).
Heading into Sunday morning, downsloping will warm up the
Finger Lakes region first, perhaps even before dawn, after which
mixing will help finally bring some of the warmer air aloft down
to the surface. Syracuse should go over to rain a couple hours
after sunrise, and then it will be slow slog for the rest of the
area. By afternoon, however, winds aloft will veer more
towards the west, with the warm nose shifting east, and profiles
generally trending towards a rain and snow (depending on
surface temps). Precip coverage will also diminish greatly after
18Z, even a little ahead of the cold front associated with this
system.
It should be noted that very cold temperatures this morning and
expected rapid cooling early this evening will keep ground
temperatures cold, and may even allow for ice accretion for a
few hours after ambient (2 meter) temperatures tick above the
freezing mark. So the risk of black ice on untreated surfaces
will linger even if ice starts melting from tree branches and
utility lines.
Much colder air will filter into the area Sunday night, and as
winds turn westerly, lake effect snow will take aim on Oneida
County, possibly grazing northern Onondaga and Madison Counties.
Localized heavy snowfall looks likely given very strong CAA, a
rapidly falling DGZ, multi-lake connection, and closer to dawn,
higher mid level RH values. The focus for the band, and heaviest
amounts, look to remain just north of the Thruway, but it`ll be
close. For now, we went with a Winter Storm Watch for Lake
Effect Snow for Oneida County which stretches on into Monday.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
Monday starts off cold and breezy behind the cold front, with
persistent west/northwest flow leading to an extended window of
lake effect Monday through Tuesday. 850mb temperatures starting
at -16 to -18C will fall to below -20C by Monday evening as
another shortwave rippling through brings a reinforcing shot of
cold air advection. Lapse rates will be steep through a
saturated DGZ, and shear increases to around 20 to 30kts which
should be sufficient to maintain a single band of snow. With a
saturated snow growth zone, a warm lake and much colder air
advecting into the region ratios should get to around 20:1 for
this event. The band first sets up north of the Thruway during
the daytime Monday, with the heaviest snow possibly in excess of
6inches expected across Oneida county.
Winds shifting to more northwesterly for a time Monday night
will allow snow showers to drop into the Finger Lakes, Southern
Tier, and portions of the Southern/Western Catskills. We may
even be able to see some enhancement from the Finger Lakes
across the Southern Tier. With ratios up around 20:1, a fluffy
inch or so is not out of the question. Any snow showers across
NE PA would be more isolated with more opportunities for some
peaks of sun as well.
Tuesday, lingering lake effect snow showers gradually become
more isolated to areas immediately downstream of Lake Ontario,
and eventually taper off during the afternoon as winds turn
lighter and soundings start to dry out. Still will not rule out
some additional light accumulations below an inch.
The other story for the beginning of the work week will be
temperatures. Monday, we should see highs only in the teens and
lower 20s, but with a bitter airmass, temperatures will plummet
into the single digits above and below zero overnight. Northern
Oneida county may even see lows in the teens below zero. This
will yield bitter wind chills into early Tuesday that will
certainly meed advisory criteria. Highs will only reach into
the single digits and possibly the teens Tuesday afternoon.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Little change to the long term. High pressure will be building
into the area by Tuesday evening, and though this should start
to bring in a moderating airmass into the middle of the week,
Tuesday night will still be very bitter with lows generally in
the single digits and wind chills below 0F. The remainder of the
period will be milder, with highs generally ranging in the 30s
and lows in the 20s. Wednesday will be dry with high pressure
in control, but another trough digging in will bring in another
round of snow showers Thursday before a ridge builds back in
Friday. Yet another system digging into the Great Lakes may
bring our next round of snow showers Friday night into the
weekend.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
Though we start off at VFR at 00Z, a storm system is about to
bring a complicated wintry mix and restrictions to all terminals
late tonight through Sunday morning. Ahead of the system, flow
off the surface will increase rapidly this evening, causing
southwesterly low level wind shear of 35-45 knots for all
terminals which will linger for a good chunk of Sunday. See TAFs
for specifics on precipitation type and timing, but all
terminals should see at least some freezing rain and sleet
before temperatures warm up for plain light rain or mist.
Ceilings will also drop into fuel alternate required to IFR
levels as the wintry mix develops; then it will persist even as
the precipitation wanes.
Outlook...
Sunday night through Monday...Ceilings improve for most
terminals Sunday night with even VFR for several into Monday,
but KSYR and especially KRME will be vulnerable to significant
lake effect snow and at times blowing snow with associated
restrictions.
Monday night through Tuesday...Occasional restrictions at NY
terminals due to lake effect snow showers, especially KSYR-
KITH-KBGM. Gusty NW winds and bitter cold Tuesday morning may
impact ground operations as temperatures dip into the single
digits, with lows well below zero at KRME.
Tuesday night through Wednesday night...Mainly VFR.
Thursday...Disturbance with chance of snow showers and
associated restrictions.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...Winter Weather Advisory from 5 AM to 4 PM EST Sunday for
PAZ038>040-043-044-047-048-072.
NY...Winter Weather Advisory from 5 AM to 4 PM EST Sunday for
NYZ009-036-037-044>046-055>057-062.
Winter Storm Watch from Sunday afternoon through late Monday
night for NYZ009-037.
Winter Weather Advisory from 3 AM to 2 PM EST Sunday for
NYZ015>018-022>025.
&&
$$
SYNOPSIS...MDP/MPH
NEAR TERM...MDP/MPH
SHORT TERM...HLC
LONG TERM...HLC
AVIATION...MDP
Area Forecast Discussion
National Weather Service Grand Rapids MI
1018 PM EST Sat Jan 8 2022
LATEST UPDATE...
Update
.UPDATE...
Issued at 1017 PM EST Sat Jan 8 2022
There are no changes planned to the Winter Weather Advisory at
this time. Everything looks to be coming together as expected
with freezing drizzle or light freezing rain now being reported at
several locations. Cloud bases have lowered below 1000 ft and 2-4
mile visibilities are common.
HRRR Bufkit profiles continue to show good omega/lift in the low
cloud deck and an unsaturated DGZ above that, so a fairly classic
looking freezing drizzle set up. QPF/glaze amounts still expected
to remain mostly below a tenth of an inch although HRRR updates
continue to suggest locally higher amounts just inland from
MKG/BIV due to enhanced sfc convergence.
At this point travel does not look to be greatly impacted, with
the MDOT MiDrive map indicating relatively free-flowing travel
speeds on the major interstates and highways. That could change
though with several hours still to go and temperatures near to
below freezing.
While many places near the lakeshore and south of I-96 will see
temps poke above freezing for a time tonight, roads/sfc temps
should remain colder with glazing of surfaces still possible.
Arrival of deeper moisture after 06Z could provide seeder-
feeder/ice nucleation activation leading to some light snow
mixing in with the drizzle before ending, especially south and
east of GRR.
We allowed the Gale Warning in the northern marine zones to
expire and transition to a Small Craft Advisory like the rest of
the zones.
&&
.DISCUSSION...(This evening through next Saturday)
Issued at 332 PM EST Sat Jan 8 2022
- Freezing light rain/drizzle tonight
Tonight we will see a period of light freezing rain/drizzle later
this evening into the early morning hours of Sunday. This event is
one of those jet entrance region lift events. There is even 50
knots perpendicular to the isentropic surfaces this evening.
However near 700 mb, the pressure deficit is near 70 mb. That
means the air being lifted at mid levels is very, very, very dry.
However there is enough moisture between the surface and 5000 ft
and there is lift there to due to the warm advection going on.
This means we are not cold enough in the clouds to create snow, so
we get drizzle. The problem there is the air is below freezing all
the way to the surface. This will mean freezing drizzle instead of
snow.
Curiously we do get lake shore convergence even so. That will
enhance the drizzle west of US-131 overnight. That would mean ice
accumulations near a tenth of an inch are possible north of
Holland and west of Grand Rapids overnight.
The timing of this is for the drizzle to develop after 9 pm and
continue past midnight before ending with the passage of the first
cold front. Currently surface temperatures are below freezing to
well south of I-80 and surface dew points are near 10 above. The
dew points will come up but not get above freezing. Drizzle
falling into air below 28 degrees is very efficient and creating
ice so this will likely create travel issues later tonight into
Sunday morning, even after the drizzle has ended since there is
not a real warm up to melt the drizzle.
- Mostly cloudy breezy and colder during the day Sunday
The cold front comes through around sunrise but the really cold
air comes in after dark. The first cold front does have cold air
with it so temperatures will fall all day. The air coming in is so
cold even if the sun were to be out (which it will not be all that
much) the temperatures would fall. In fact temperatures will
likely fall into the teens by late Sunday afternoon. Normally
we`d get lake effect snow showers with an event like this but the
polar jet axis does not come through here till late in the day on
Sunday. It will take that to get the lake effect snow showers up
and going once again.
- Arctic cold front brings snow shower and colder Monday
The passage of the polar jet axis puts us in deep cold air and
typically that means lake effect snow showers when 850
temperatures get much below -12c. As we have been saying, this is
the coldest air of the season to date. 850 temps fall below -20c
on Monday over just about the entire state of Michigan. This will
likely be the first day this winter with day time highs below 20
degrees across most if not all of the area. In this situation we
have a large surface high moving into the area. The models are not
doing much at all with lake effect snow showers due to the
anticyclonic winds around the surface high. However, it has been
my experience that with air this cold and with us being on the
cyclonic side of the polar jet we will get a surface trough over
Lake Michigan. That will be just enough to kick of snow showers
anyway.
Due to the lack of Moisture at mid levels and the DGZ nearly on
the ground, we will not create large fluffy snowflakes. That will
limit accumulations but it will be breezy and small flakes can
really lower the visibility so there may be travel issues later
Sunday into Monday even so.
- Warmer than normal and dry midweek, the much cold and it stays
The polar jet comes back through Monday night. That will end the
snow showers and bring milder air back into the area. The really
cold air will not come back until next weekend. We have a system
passing north of us mid-week but that will not impact our weather
much. It is later Friday we get another digging northern stream
jet that will push a strong cold front through the area. This time
though it seems once we get into the cold air, it will stay
longer and not just last 2 day. In fact the ensembles and
operational runs of the GFS, ECMWF and Canadian models all show
highs below freezing from Jan 15th through the 24th (and beyond).
So, winter is HERE!
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 702 PM EST Sat Jan 8 2022
Some fairly big impacts to aviation are expected tonight due to
icing and IFR or lower cigs. Light freezing rain/drizzle will
become widespread over the next few hours with moderate icing
expected between the sfc and 6000 ft. The current MVFR cigs will
lower into IFR or LIFR category before midnight at most
locations.
Improving conditions will arrive from the northwest toward 12Z
Sunday, with any freezing drizzle ending and cigs improving
quickly to MVFR. A few flurries are possible Sunday but no
appreciable reductions to visibilities are anticipated at this
time.
Gusty southerly winds to 25 kts tonight will shift to the
west/northwest for Sunday and remain gusty.
&&
.MARINE...
Issued at 332 PM EST Sat Jan 8 2022
We have a gale warning in effect over our northern part of the
near shore and small craft over the rest of the near shore. At
this point I see no real reason to change that though we are not
really getting any reports of gales yet, it still could happen so
it`s best to leave it as is. Once the first cold front comes
through we get all that cold air moving in. So, guess what, we
will need a small craft advisory into Tuesday but we did not
change the lenght of the small craft advisory just yet, once the
gales are done, then we will likely do that.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Winter Weather Advisory until 4 AM EST Sunday for MIZ037>039-
043>045-050-051-056>059-064>067-071>074.
LM...Gale Warning until 10 PM EST this evening for LMZ848-849.
Small Craft Advisory until 7 AM EST Monday for LMZ844>847.
&&
$$
UPDATE...Meade
DISCUSSION...WDM
AVIATION...Meade
MARINE...WDM
Area Forecast Discussion
National Weather Service Houston/Galveston TX
554 PM CST Sat Jan 8 2022
.AVIATION [00Z TAF Issuance]...
With the bulk of the stronger cells moving out to the east and the
sunsetting, it looks like things are on a downward trend as far as
convective activity goes. However, in the wake of these storms and
its associated coastal low, deep/strong onshore winds will persist
across the region with MVFR/IFR ceilings prevailing tonight. Light
showers/areas of drizzle/patchy fog are expected as well given the
continuing WAA/fetch from the Gulf. For now, going to maintain the
current timing of this next cold front: reaching our northern ter-
minals around noon...central mid afternoon and the coast late aft-
ernoon. 41
&&
.PREV DISCUSSION... /ISSUED 230 PM CST Sat Jan 8 2022/
SHORT TERM [Today through Sunday Night]...
Currently, a warm front is draped across the I-10 corridor with
widespread showers across the eastern portion of our CWA. Activity
has been further northeast than previously anticipated, but storms
will continue to increase in strength and coverage this afternoon
and early evening as the warm front pushes further north. Satellite
imagery shows breaks in cloud cover west of I-45 which should help
destabilize the atmosphere further for that area. SPC mesoanalysis
also hints at this with higher CAPE values west of I-45 and less
CIN. Scattered showers are currently growing across that area, but
as previously mentioned, we expect this area to have storms grow in
strength and coverage over the next few hours. Across our CWA, these
storms will be capable of producing strong to severe wind and small
hail. Our HGX radar VWP shows a significant decrease in low level
directional shear which indicates a drop in low level helicity
across the area, but some short term soundings such as the RAP and
NAM still show decent values of effective SRH near 150-200 m2/s2
across our CWA, so we still can`t rule out some rotating updrafts
and possibly some brief and weak tornadoes. With strong buoyancy of
1500-2000 J/kg, 90th percentile PWs, skinny cape, and organized
updrafts, some of these cells will also be capable of producing some
localized heavy rainfall amounts with rainfall rates near 2 inches
per hour with the strongest storms. Otherwise, 1 to 2 inches are
expected across the area over the weekend with isolated higher
amounts possible.
Overnight, the warm front will still linger across our CWA and we`ll
still see some scattered to widespread showers, but the threat for
severe weather and heavy rainfall will begin to diminish. Overnight
lows will stay warm and humid in the upper 60s. Fortunately, a cold
front is expected to arrive tomorrow and reach the Brazos Valley by
early afternoon and reach the coast by the late evening. This should
sweep out any lingering precip as the coast pushes offshore. Temps
and humidity will quickly decrease behind the frontal passage.
Northern counties will be noticeably colder and reach the mid 60s
tomorrow, but elsewhere will have plenty of opportunity to heat up
ahead of the frontal passage and reach the mid 70s. Overnight lows
will dip into the lower 40s for our northern counties and upper 40s
everywhere else as CAA behind the front ushers in colder and drier
air.
Lenninger
LONG TERM [Monday through Saturday]...
A drier and cooler air mass will settle across Southeast TX on
Monday with surface high pressure building across Central TX. High
temperatures in the mid 50s to low 60s expected. It will remain
breezy with northerly winds ranging between 10 and 15 mph during the
day and relax Monday night as the high pressure moves closer to the
local area. CAA will allow for low temperatures to dip into the low
to upper 30s for areas north of I-10, the mid 30s to low 40s for
areas souther of I-10, and the low to mid 40s along the immediate
coasts and Barrier Islands. Light variable winds expected Tuesday as
the high pressure shifts eastward. Highs will be in the upper 50s to
low 60s and lows in the upper 30s to mid 40s early Wednesday
morning. By midweek, SE Texas will be wedged between a mid-upper
level low moving eastward over the northern portions of Baja
California and an upper level trough moving into the Great Lakes
region. The upper low is expected weaken as it slowly moves into
the Four Corners region on Thursday and begins to merge with a
trough located over the northern Great Plains as it moves into
Northern TX/Oklahoma/Kansas region on Friday. Low pressure along
the surface and associated cold front will move into the Northern
TX and Oklahoma by early Friday and could cross Southeast TX
sometime late Friday into Saturday morning. We can expect rain
chances to increase by Thursday night or early Friday as low
level moisture and instability increases ahead of the front,
possibly some streamer showers. The higher PoPs however, remain
just ahead and along the front (Friday into Saturday morning).
24
MARINE...
Moderate to strong south to southeast winds and elevated seas will
persist across the bays and Gulf waters through tonight. Chance of
showers and thunderstorms expected through Sunday as a warm front
continues to move further inland today followed by a cold front
moving into the coastal waters Sunday afternoon. Strong northeast
winds will develop in the wake of the front Sunday night into Monday
and will likely require Caution Flags and Advisories for the bays
and Gulf waters. Winds relax Tuesday and turn northeast to east as
high pressure moves close to the region. Light east to southeast
winds expected Wednesday with onshore flow persisting through
Friday. Chance of rain will return on Friday ahead of the next cold
front which is expected to move into the coastal waters sometime
late Friday into early Saturday.
24
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 60 66 43 58 35 / 50 0 0 0 0
Houston (IAH) 67 74 47 59 39 / 70 60 10 10 0
Galveston (GLS) 68 73 51 61 49 / 80 60 10 10 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...High Rip Current Risk until midnight CST tonight for the
following zones: Bolivar Peninsula...Brazoria Islands...
Galveston Island...Matagorda Islands.
GM...Small Craft Advisory until midnight CST tonight for the
following zones: Waters from Freeport to Matagorda Ship
Channel TX from 20 to 60 NM...Waters from High Island to
Freeport TX from 20 to 60 NM.
&&
$$
Area Forecast Discussion
National Weather Service Wilmington NC
1029 PM EST Sat Jan 8 2022
.SYNOPSIS...
High pressure to slide offshore from the Mid-Atlantic Coast tonight
while a weak coastal trof persists just off the NC and SC Coasts. A
strong cold front accompanied with showers, will approach from
the NW Sun, sweeping off the Carolina Coasts and offshore late
Sun night. Cold high pressure will follow through the upcoming
mid-week period.
&&
.UPDATE...
Some tweaking to sky conditions, based on latest sat imagery
and HRRR model trends and a quick 1st look at 00z model runs.
Temps also tweaked base don extent of the blanket of clouds.
Held onto the NE-E winds longer across the FA and within the
nearshore waters based on slower demise of the inverted sfc trof
ie. coastal trof.
733PM EDT Update...
Moisture in the low levels has been creeping northward
from southern SC from this aftn and early this evening...and
has now encompassed atleast 2/3rds of the FA with the exception
of the immediate coast and a portion of Southeast NC. Sky
conditions have been updated to account for this northward push
of stratocu cloudiness. Stratocu offshore from the coast will
eventually get drawn onshore overnight into Sun as a weak
coastal trof drifts to the immediate coast. This blanket of
clouds will limit the drop of temps this evening except across
Southeast NC. Temps will either straight line as the cloud deck
pushes overhead or actually climb a few degrees overnight as sfc
dewpoints also moderate. Tweaked seas a foot hier this evening
but kept the trend decreasing after midnight as wind produced
seas subside-some.
&&
.NEAR TERM /THROUGH SUNDAY/...
Latest sfc analysis shows 1037 mb high pressure centered over
the DELMARVA. The high slides offshore tonight but continues
ridging down into the local area, leading to light NE flow and
mostly clear skies until some increasing clouds late. Low temps
range from near 30 inland to the upr 30s along the coast.
Continued dry then for daytime Sunday ahead of the next cold
front. Main story will be a brief return to above normal
temps...highs 65-70 with increasing low-level WAA. Expect the
rain to hold off until the evening/nighttime as mid levels will
remain rather dry and shortwave energy will be positioned still
well off to the west.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
Alberta Clipper system drags a cold front across the area quickly
Sunday night. Forecast rainfall amounts are still consistent, coming
in around half an inch, with locally higher amounts possible. Still
think it`s possible that these amounts could decrease in future
forecasts, as the surface front moves through well before the jet
dynamics sweep through.
The front will be offshore by sunrise Monday morning, bringing very
cold air behind it. Rain quickly tapers off in a west to east
fashion, with chances along the coast dying off by late Monday
morning. High temperatures for the day (around 50) will be recorded
not long after the clock strikes midnight and the day changes from
Sunday into Monday. From there, temperatures will drop throughout
the day, with the mid 40s likely by Monday afternoon.
Strong high pressure originating from the upper Midwest quickly
slides down into the Ohio River Valley by Monday night. This sets up
a decent night for radiational cooling, and temperatures dive down
into the mid 20s.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
Tuesday is the coldest day of the period, as high pressure shifts to
just north of the area. Expect highs in the lower 40s and lows in
the teens to lower 20s with clear skies.
High pressure tries to shift offshore by Wednesday, but won`t get
very far. As a result, very little southerly flow is introduced.
Wednesday`s highs are only a few degrees warmer than the previous
day, with lows near freezing.
Temperatures slowly continue to modify through the rest of the
period, with highs in the upper 50s possible by Saturday. Meanwhile,
an upper low near the Baja California region introduces some split
flow for our neck of the woods towards the end of the work week,
setting up for a potentially challenging forecast. For now, forecast
remains dry. By the weekend, another clipper system may emerge and
drag another cold front across the area, so I`ve kept a chance of
rain for next Saturday.
&&
.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
VFR to dominate this issuance period. Ceilings will become
BKN/OVC 3500-4500 ft this evening thru the overnight as a
stratocu deck drifts/develops across the area. During Sun this
stratocu deck will become SCT with a BKN 8k-12k ft altocu deck
dominating much of the day. A coastal trof will just off the
coast will drift onshore and dissipate with initially NE-E 4 kt
or less flow becomes a synoptic driven SE-SSW flow around the
departing offshore Mid-Atlantic high. The sfc pg will tighten
Sun aftn/evening with winds increasing to around 10 kt with
around g15 kt.
Extended Outlook...VFR early Sun evening deteriorate to MVFR
and possibly periodic IFR from pcpn and ceilings associated with
a CFP Sun night or early Mon. VFR and dry conditions to follow
Mon through mid week with dry and cold high pressure dominating.
&&
.MARINE...
Through Sunday: After some gusts up to 15-20 kt early this
evening, expect mainly ~10 kt winds for tonight out of the east
as sfc high pressure is positioned off to the NE. A cold front
then approaches from the west on Sunday, with SSW flow slowly
increasing through the day, up to 15-20 kt by late aftn. Seas
2-4 ft through this timeframe, which includes a weak 8-9 second
swell component.
Sunday Night Through Thursday: Strong cold front moves through
the area Sunday night, where SSW flow will quickly transition to
NW flow by Monday morning. Seas increase, but remain below
Small Craft Advisory thresholds. However, there is increasing
confidence that winds will increase after frontal passage,
pushing to SCA territory. An advisory is possible late Sunday
night into early Monday afternoon. High pressure starts to
settle in, with decent northerly flow at 15-20kts and seas at
2-4ft through Tuesday. Wednesday, winds decrease to around
10kts, and back slightly to the NNE, with seas at 1-3ft. Winds
continue to back to the NW by Thursday, increasing to 10-15kts,
with seas consistently hanging at 1-3ft.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.
&&
$$
SYNOPSIS...DCH
UPDATE...DCH
NEAR TERM...MAS
SHORT TERM...IGB
LONG TERM...IGB
AVIATION...DCH
MARINE...MAS/IGB
East Central Florida Forecast Discussion
National Weather Service Melbourne FL
747 PM EST Sat Jan 8 2022
.DISCUSSION...
Currently-Tonight...Strong high pressure emerging offshore the Mid-
Atlc seaboard will produce defined onshore flow conditions locally
into early next week. Marine based CU were producing some weak radar
returns, however the overall airmass wl not support much beyond a
transitory sprinkle into the overnight period. Silent PoPs wl be
maintained.
Winds have diminished west of the Indian River and interior with a
scattering of clouds expected to remain overnight. Lows in the upper
50s across the north to the upper 60s/lower 70s for the Treasure
Coast.
from prev disc...
Sunday...The surface high over the western Atlc basin will retreat
further seaward driven east by the next approaching cold front. The
ridge axis will dig deep towards the FL peninsula, with easterly
winds veering southeast by mid morning. This southeasterly component
may drag additional moisture from the Caribbean towards south FL
late in the afternoon. PoPs will return to the forecast but only
spread across the south from Stuart towards the upper Kissimmee
River basin and remain at a mere 15-20%. Winds will subside becoming
5-10 mph, with afternoon highs returning once again to the 80s.
Monday-Tuesday...Things will finally get a little more "exciting"
around the Space Coast to kick off the workweek as a strong cold
front approaches the region. High pressure will remain to the east-
northeast of Florida as it weakens and slides farther away the
northeastern seaboard - allowing a shortwave to deepen as it moves
across the upper-Midwest on Monday. Reflected at the surface, a cold
front will slowly dig east-southeast and sweep across central
Florida with the tail end likely clearing the Treasure Coast by late
Monday into early Tuesday.
Ahead of the boundary, isolated-to-scattered showers and lighting
storms will potentially develop near the Treasure Coast and move
across the Gulf Stream with lingering moisture from a "washed
out" boundary coupled with weak onshore flow (mainly south of
Melbourne) leading to sea breeze driven precipitation to develop
and drift towards the coast during the morning hours before flow
backs offshore. A better chance for showers and storms are
expected to spread east-southeastward as the previously mentioned
cold front moves across central Florida through the afternoon and
evening. While guidance is in decent agreement with the timing
and coverage of precipitation, they somewhat disagree on how much
instability we will see. The GFS indicates weak instability,
however, that tends to be a trend with the model recently, so
I would think the RAP, NAM, and HRRR are closer to reality with
moderate instability more plausible, especially given the
synoptic setup.
With that said, some storms may become strong with moderate
instability expected, moderate helicity values, conditionally
unstable mid-level lapse rates, as well as relatively cold air
aloft. We`ll need to watch for flooding, especially towards the
Treasure Coast where signals point to the potential for training
storms/precipitation. Any strong storms that develop will have the
potential to produce gusty winds, heavy rainfall, flooding, and
brief spinups (mainly near the coast). Dry conditions will follow
behind the front Tuesday night as it moves out to sea - leaving
the chance for showers and lightning storms off the coast and over
the local waters through the day on Tuesday. High temperatures
will reach the mid 70s to low 80s on Monday before FROPA occurs
and drops highs into more seasonable levels with afternoon
temperatures in the mid 60s to mid 70s. Low temperatures will be
in the upper 50s to mid 60s before dropping further Monday night.
Temperatures will drop down into the upper 40s to mid 50s inland
and the mid 50s to mid 60s near the coast.
&&
.AVIATION...
VFR. A steady-state sct CU field wl continue with sct coverage.
Onshore winds of around 6 to 12 knots tonight, veering southeast
Sunday as the surface high drifts seaward. Rain chances remain
minimal, with no impacts to terminals expected.
&&
.MARINE...
Tonight-Sunday...Seas of 3-5 feet tonight. The Small Craft Advisory
will expire at 10 PM, reverting to caution statements. Sunday, winds
will veer southeasterly and diminish below 15 knots with seas 4-5 ft.
Monday-Wednesday...Conditions over the waters will improve
temporarily Monday morning before a cold front enters the Atlantic
waters on Tuesday. West winds around 10-15kts will increase to 20-
25kts and veer to the north-northeast by Monday evening. Swell
heights will build from 3-6ft north to south on Monday to 6-8 ft
with up to 11 feet over the offshore (20-60nm) waters. SCA will
likely be needed by Monday night.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 63 80 61 77 / 0 10 20 50
MCO 63 83 64 80 / 0 10 20 50
MLB 66 80 64 80 / 0 10 30 60
VRB 66 82 63 82 / 0 10 30 60
LEE 61 83 63 79 / 0 10 20 40
SFB 63 82 63 80 / 0 10 20 50
ORL 64 83 65 80 / 0 10 20 50
FPR 66 79 62 80 / 10 20 30 60
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...Small Craft Advisory until 10 PM EST for Sebastian Inlet
to Jupiter Inlet 0-20 nm-Sebastian Inlet to Jupiter Inlet
20-60 nm-Volusia-Brevard County Line to Sebastian Inlet 20-
60 nm.
&&
$$
JP/AC
Area Forecast Discussion
National Weather Service Blacksburg VA
953 PM EST Sat Jan 8 2022
.SYNOPSIS...
A front moves across Sunday into Sunday night with mainly rain,
with a brief period of freezing rain over Southeast West
Virginia into the Alleghanys Sunday morning. High pressure
builds in Monday, with mainly dry weather expected into midweek.
&&
.NEAR TERM /THROUGH SUNDAY/...
As of 953 PM EST Saturday...
Winter Weather Advisory remains in effect for portions of southeast
WV into the Alleghanys of Virginia Sunday morning for freezing rain.
High pressure along the coast continues to move east tonight as cold
front approaches from the west. Rain along the frontal boundary is
pushing into the Ohio valley this evening. This evening 00z RNK
sounding showed a warm nose around plus 6. As stated earlier expect
a few pockets of freezing rain before the intensity of the rain
warms the surface/low levels to above freezing Sunday morning.
Looking at the latest HREF data, appears that forecast capture the
areas with the best potential for freezing rain. The Highresw-ARW
and HRRR still support the precip arrival time after 12z in the west
tonight. As the precipitation get closer may need to expand the
weather advisory or issue sps for additional pockets of freezing
rain depending on conditions. It still looks like a small
window for freezing rain with amounts light and less than a
tenth of an inch. Will review the 00z run of models before
making any additional changes.
Previous discussion:
As of 633 PM EST Saturday...
Winter Weather Advisory remains in effect for portions of
southeast WV into the Alleghanys of Virginia Sunday morning.
Made some minor adjustments in temperatures for this evening
into tonight utilizing the latest surface obs, their trends and
blended in the NBM. Made some minor adjustments in cloud cover
for tonight. The Highresw-ARW and HRRR still support the precip
arrival time after 12z. More changes later tonight.
Previous discussion:
As of 125 PM EST Saturday...
Expect A Little Ice Across The Alleghanys and Southeast WV
Sunday Morning...
The deep freeze will rise to near or just below normal temperatures
by Sunday afternoon, thanks to increasing heights, and southwest
flow ahead of a cold front.
Prior to it, cold high pressure centered along the mid-Atlantic
coast is going to shift east through tomorrow, while a warm
front/isentropic lift enhance across the TN Valley into the central
Appalachians late tonight, with clouds increasing this evening, and
lowering overnight.
Not a classic or hardly an in-situ wedge set up, but with it being
very cold the last couple of nights, and temps expected to drop into
the upper teens/lower 20s late this evening then steady or rise
overnight, we may be seeing an issue with precip coming in around
12z/7am in the WV mountains.
Models have slowed down timing of precip til mainly after 12z, and
most agree that a strong low level 8h jet will send a warm nose of
of +7 to +10C over the area when the precip arrives. This leads to
somewhat of a conundrum, as think the sub-freezing surfaces and
temps for a couple hours will harness freezing on contact of
rainfall, before the intensity of of the rain warms the surface/low
levels to above freezing by late Sunday morning.
Although there does not look like a large window for ice and amounts
will be under a tenth of an inch, it only takes a trace of ice on
roads/sidewalks to cause problems. Will be putting up a winter
weather advisory for portions of southeast WV into the Alleghanys of
Virginia starting around 5am, lasting til 11am, though bulk of
accretion will likely be a 2 hour window from 11/13z/-13/15z.
Otherwise, should see convergence of moisture along/ahead of the
cold front to bring a period of rain to most of the forecast area by
late Sunday afternoon. The rainfall totals overall should be higher
in the WV/far SW VA/NC mountains, where up to an inch is likely,
with around a half inch for most of the area.
Forecast confidence is high for all but ice amounts this forecast
period.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 100 PM EST Sunday...
A cold front will move across the area Sunday evening with rain
ending by early evening across the mountains and around midnight
over the piedmont. Behind the front, a 45 kts cross-barrier jet and
a tight pressure gradient will bring windy and gusty conditions to
the area Sunday night into Monday. Winds relax late in the afternoon
as high pressure builds in.
An upper level trough will pivot over the region Monday night. The
GFS brings upslope snow showers Monday afternoon into Tuesday
morning. The ECM only brings an increase in clouds. Since
substantial dry air follows the front, leaning towards the ECM. More
dry weather follows this trough with high pressure building over the
region Tuesday.
Temperatures will remain cooler than normal.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 115 PM EST Sunday...
An upper level trough will dive out of the Great Lakes and into the
mid-Atlantic states Thursday. Models differ with the GFS being
wet and the ECM only increases clouds. Leaning towards the ECM
with lingering dry air in the region and the Gulf being closed.
We will carry low PoPs just in case moisture from the Great Lake
survives the trip.
There is another potential weather maker for next weekend. Models
are in better agreement with a frontal passage Saturday.
Temperatures becoming warmer than normal Thursday continuing into
the weekend.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
As of 658 PM EST Saturday...
Pilots should watch for icing and low level wind shear
late tonight into Sunday.
VFR conditions will continue this evening into tonight. High
pressure will slowly slide east tonight as a cold front
approaches from the west. In general, clouds will increase
tonight. Rain associated with frontal boundary will push into
the western taf sites of BLF and LWB by 14-16z. At the start,
temperatures will be cold enough to have freezing rain at LWB
for a couple hours. Early Sunday morning, moisture increases
enough to bring all sites to ceilings to at or below 3000ft,
though confidence is higher in the mountains as precip moves in.
Vsbys also could be MVFR at BLF/LWB by 18z.
In addition, a low level inversion sets up tonight, while a very
strong low level jet from the southwest moves overhead, which
looks to bring the potential for low level wind shear to all
taf sites in the 09-19z time frame. Rain will be moderate,
possibly heavy in the mountains Sunday afternoon. MVFR and IFR
conditions will be common in areas of rain.
Average confidence in ceilings,visibilities and winds during the
taf period.
.Extended Aviation Discussion...
Rain moves out by Sunday evening, and until then, expect sub-
VFR weather.
As the front exits on Sunday night, any lingering moisture near
BLF and LWB may turn back to snow before fading by Monday as
drier air returns. Brisk northwest winds are anticipated for
Monday, but high pressure should build overhead by Tuesday to
provide VFR conditions at all TAF sites through Wednesday. Dry
weather expected Thursday into Friday. Moistures return to the
west late Friday night into Saturday with a front.
&&
.EQUIPMENT...
The tipping bucket at the Bluefield ASOS is inoperable. Return
to service is expected sometime Monday. Until then precipitation
will not be reported from KBLF.
In addition, there is a comms outage at Bluefield preventing the
observation from being transmitted at times.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...Winter Weather Advisory from 4 AM to 11 AM EST Sunday for
VAZ018>020-024.
NC...None.
WV...Winter Weather Advisory from 4 AM to 11 AM EST Sunday for
WVZ042>044-507-508.
&&
$$
SYNOPSIS...WP
NEAR TERM...KK/WP
SHORT TERM...RCS
LONG TERM...RCS
AVIATION...KK/WP
EQUIPMENT...SH