Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/20/20
Area Forecast Discussion
National Weather Service Gaylord MI
1052 PM EDT Mon Oct 19 2020
.UPDATE...
Issued at 953 PM EDT Mon Oct 19 2020
Compact upper jet core is pivoting across central and southern
Lower Michigan this evening...along a fairly tight thermal
gradient sitting across the state. F-gen response across northern
Michigan has/is producing a broad area of light radar returns
across the CWA out of a relatively higher cloud base, most of
which is not reaching the ground. Meanwhile, some very spotty
showers (a mix of rain and snow) have also popped underneath, a
combination of terrain and lake enhancement.
Upper jet core and associated broad are of light radar returns zip
off to the east over the next several hours with surface high
pressure/subsidence building in overnight. But, cooler air will
also spread southward through the region as low level flow veers
more N/NW overnight. This will keep spotty nuisance lake
induced showers going...generally near the coasts. Low impact
overall, but a few spots could pick up a light accumulation of
snow.
&&
.NEAR TERM...(Through Tuesday)
Issued at 321 PM EDT Mon Oct 19 2020
...Staying cool...
High impact weather potential: none.
High pressure is centered somewhat north of the Twin Cities. Ridging
extends east into northern lower MI. There has been a flare-up of cu
over eastern upper and far northern lower MI, where the lakes are
contributing the most low-level moisture. A few sprinkles or weak
showers are percolating here. In addition, mid and high clouds are
gradually impinging from the sw and w.
Nothing too terribly impactful expected in the near term. Fgen
processes (associated with a shortwave zipping into central lower
MI) will support synoptic precip in parts of southern lower MI
tonight. Most of this is not progged to get this far north. In
particular, most models do not bring the precip presently seen
in southern MN and environs into northern MI. `Most` models is
not quite `all` though, with the HRRR and Rap occasionally
generating enough fgen far enough north to get light precip going
near and south of HTL. This is mainly in the 1st half of the night
(before 2 am). If this does make it to terra firma, light mixed
rain and snow is possible.
Otherwise, lake effect processes (with some diurnal heating
contribution this evening) will continue to generate some weak
showers at times. This will be mainly over coastal nw lower MI,
on up into the Straits and eastern upper MI. These are more likely
to be liquid this evening and very close to Lake MI, and more
likely to be snow overnight and somewhat inland. The risk for
lake effect precip diminishes toward morning, as inversion
heights lower greatly as mid-level heights briefly build. Minimal
chances for precip Tue morning, and clouds will thin out a bit,
especially in eastern upper MI. Another well-developed low will
push across the northern plains on Tuesday, with increasing
warm/moist advection ahead of it. This system is far more likely
to bring us precip beginning Tue night, but there is a chance for
light rain arriving west of I-75 by late Tue afternoon.
Min temps tonight mid 20s to around 30f. Max temps Tue mid to upper
40s.
&&
.SHORT TERM...(Tuesday night through Thursday)
Issued at 321 PM EDT Mon Oct 19 2020
...Above Normal Temperatures on Thursday...
High Impact Weather Potential...Minimal.
Pattern Synopsis/Forecast and possible outcomes...Tuesday night, The
warm front continues to move north and the precipitation, mainly
rain, continues to spread across N Lower and E Upper before drier
air moves in after 09z/Wed. With the warmer 850 mb temperatures and
the dry air, the precipitation ends during Wednesday afternoon, with
clouds on the SW horizon from the next wave to move into the region
after 00z/Thu. Wednesday night, Rain begins to move up out of the
Mid-Mississippi Valley, overnight, depending on the model. The
models are primarily keeping the rain south of M-55, with some
showers north of M-55. This looks to be backed off quite a bit from
previous runs with the likely rain as far north as M-32. The warm
front moves north Thursday, and the dry air goes north with it. This
pushes the best moisture into the region and along the front, near
the sfc low. So rain through 00z/Fri.
.LONG TERM...(Thursday night through Monday)
Issued at 321 PM EDT Mon Oct 19 2020
High Impact Weather Potential...Thunder is possible Thursday night
into Friday, but severe weather is not expected at this time.
Extended (Thursday Night through Monday)...The models are in better
agreement on the cold frontal passage and the sfc low passage for
Thursday night into Friday night. Models are showing elevated
convection for Thursday night into Friday morning, as the front
passes through the forecast area. The CMC is the quickest of the
cold frontal passages, with the GFS and ECMWF about the same. Will
lean toward the GFS/ECMWF idea, and keep the Thunder in the forecast
and then the cold air to push through by 00z/Sat. The mid levels dry
out, but 850 mb remains moist, with the 850 mb temperatures falling
to around -5c/-6c in N Lake Michigan, and getting closer to -7c by
12z/Sat. So LE Precipitation is possible, and depending on the
temperatures will be a mix or all snow. This may last through
Saturday to an extend with the 1000-850 mb wind being out of the
north. The GFS pushes the -8c line (which would give the possibility
of all snow even near the lakes) by 12z/Sun. The ECMWF isn`t as cold
and is more anti-cyclonic, almost N to NNE in the winds. The CMC is
SE winds and warming. So will leave the consensus model, until the
deterministic models get together. Sunday, the next system moves
into the region. With the cold temperatures on the GFS, snow is a
possibility, but the warmer temperatures on the ECMWF are more of
rain or a mix. Monday, the ECMWF shows it cold enough for snow
especially Monday night.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1052 PM EDT Mon Oct 19 2020
Overall VFR conditions continue. Upper level wave traversing
through the western Great Lakes is bringing some lowering CIGS
(VFR) and a swath of weak precip returns through northern Lower
Michigan. Most is not reaching the ground, although a few
locations have reported some light precip at times over the last
several hours. Some very spotty lake and terrain induced showers
are also present across northern Lower Michigan and on the lakes.
Spotty precip (rain trending toward snow) will be the rule through
the balance of the night while upper level wave exits quickly to
our east and low level flow veers more northerly off the lakes.
Largely VFR, although there may be some brief MVFR CIGS lurking
around.
High pressure will be in control for much of Tuesday although overall
cloudy skies (VFR cigs) continue. High pressure quickly moves out
of the region later in the day while our next storm system swings
into the region Tuesday night and pushes another round of rain
into the region. Conditions will trend to MVFR and even possible
IFR Tuesday night as precip spreads into the region.
&&
.MARINE...
Issued at 321 PM EDT Mon Oct 19 2020
Light winds/waves in place, as high pressure in MN/WI extends
ridging into northern lower MI. This high will start to head off
to our east Tuesday, as low pressure advances into the northern
plains. Se winds will increase Tue night, and small craft
advisories may re-enter the picture beginning then.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...BA
NEAR TERM...JZ
SHORT TERM...JL
LONG TERM...JL
AVIATION...BA
MARINE...JZ
Area Forecast Discussion
National Weather Service Charleston SC
1035 PM EDT Mon Oct 19 2020
.SYNOPSIS...
High pressure and a weak coastal trough will persist into late
week. Next weekend, a cold front could push into the region and
stall near the Southeast coast.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 1030 PM: KCLX detected a few weak returns across the outer
GA waters. The current forecast features SCHC PoPs over the
outer waters, slowly increasing near shore through the rest of
the night. Based on recent observations and MOS, temperatures
are on pace to reach the upper 50s inland to the mid 60s along
the coast by daybreak.
As of 840 PM: IR satellite indicated a band of stratus between
20-40 NM offshore, drifting westward. Based on satellite trends,
cloud cover will increase from east to west across the forecast
area tonight. The forecast will be updated to increase sky
cover. Earlier shower activity over the outer GA waters has
generally ended. However, another round of showers may develop
over the Gulf Stream and drift over the marine zones late
tonight.
As of 650 PM: KCLX detected a band of light showers passing over
the outer GA waters, tracking toward the SSW. The latest run of
the HRRR indicates that showers will persist through the rest of
the evening, increasing over the near shore waters late tonight.
This update will feature greater sky cover through the rest of
the night and will indicate light QPF along the CHS Co. coast.
Previous Discussion:
Tonight: Overall, little to no change in the setup overnight.
High pressure will remain the primary feature as it extends from
the New England coast through much of the Southeast and Deep
South. A coastal trough will gradually drift closer to the coast
overnight, with isolated showers developing mainly across the
coastal waters. By sunrise, some model solutions show showers
brushing the coast, so rain chances increase into the 20 percent
range late tonight right along the coastal corridor. Cloud
cover will increase through the overnight as stratocumulus
advects onshore. Expect a mild night with lows ranging from the
upper 50s inland to the upper 60s at the beaches. Overall, lows
will be 5-7 degrees above climatological normals for late
October.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
Deep layer ridging will predominately dominate across the
region through Thursday, before starting to weaken as Tropical
Storm Epsilon treks north across the Atlantic. Dry air will
start to give way to deeper moisture associated with a coastal
trough, slightly increasing rain chances for Tuesday, mainly
along the SE GA coast. By Wednesday and Thursday, PWATs will
increase to around 1.5 inches, especially across SE GA and far
SE SC where chances of showers will be best. Though, have
maintained a slight chance of showers across the SC Lowcountry.
There will be sufficient instability each day for isolated
thunderstorms so have also maintained slight chance across the
area. Overall, severe weather is not expected. Highs will be in
the upper 70s to low 80s each day with lows in the mid to upper
60s with low 70s along the coast.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Thursday night through Friday: Models start to diverge during
this period, but generally agree that this will be the last
period with the ridge to the northeast and northeast low level
flow. By Saturday, global models indicate that the persistent
deep layer ridge over the eastern U.S. will break down as the
upper flow tries to become more zonal in response to a broad
upper trough over the central portion of the country. On
Saturday, the ECMWF tries to bring a moderately strong upper
level shortwave over the region in the southwest upper level
flow, but the Canadian and GFS models do not agree with this
solution. By Sunday and Monday, the consensus solution points
toward a broad/deep upper level trough over the central U.S.,
with our region under a mid and upper level ridge. Given the
uncertainty, have gone with chance PoPs through Saturday, then
slight chance Sunday and Monday as the upper ridge tries to
build back. Temperatures are expected to remain above normal
through the period, especially minimum temperatures.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
VFR conditions forecast to continue at both terminals tonight.
During the pre-dawn hours, MVFR ceilings may approach the
terminals from the Atlantic. Guidance indicates that MVFR
ceilings may occur from time to time, especially during the
early daylight hours. The potential for MVFR ceilings will be
highlighted with a TEMPO from 10-14Z. A few weak showers may
approach from the east during the afternoon, coverage appears
too limited to add to the TAFs. Winds will remain from the ENE
through the 0Z TAF period.
Extended Aviation Outlook: Mainly VFR with periods of MVFR
possible in isolated to scattered showers.
&&
.MARINE...
Tonight: The seemingly never ending period of northeast winds
will continue through the night. Wind speeds will generally hold
in the 15-20 knot range, diminishing a bit by sunrise Tuesday.
Seas are forecast to be 3-5 ft across the nearshore waters and
5-6 ft for the outer waters. The Small Craft Advisory for the
outer Georgia waters has been extended to go through the night.
Tuesday through Saturday: Deep high pressure will prevail
across the waters, keeping winds east-northeast through
Saturday. Winds will generally be 10-15 kts with gusts to 20
kts. As TS Epsilon treks north across the Atlantic, long period
swell is expected to gradually increase. Therefore, a Small
Craft Advisory will remain in effect for 5-8 ft seas across the
outer Georgia waters through at least Saturday. Across the
nearshore waters, seas will generally be 2-5 ft but could see
occasional 6 ft seas by Thursday and a Small Craft Advisory
could be needed.
Rip Currents: Decided to go with a Moderate risk of rip
currents for the Georgia coast through the rest of the day after
reports of rough conditions at Tybee Island. The Fire Chief
said conditions were worse than yesterday. Persistent northeast
winds will drive a strong longshore current and increase the
chance of rip currents.
As TS Epsilon treks north and long period swell increases,
there could be an elevated risk of rip currents by the end of
the week and through the weekend for all beaches.
&&
.TIDES/COASTAL FLOODING...
SC coast: Due to higher than normal astronomical tides,
moderate coastal flooding is expected on Tuesday. Minor coastal
flooding is then expected on Wednesday and Thursday. By Friday,
tides should be below minor coastal flooding criteria.
Georgia coast: Tide levels could reach minor coastal flooding
levels Tuesday morning. However, guidance keeps tide levels
below coastal flooding thresholds as astronomical tides
gradually fall through the week.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory until 7 AM EDT Sunday for AMZ374.
&&
$$
NEAR TERM...NED
SHORT TERM...
LONG TERM...RFM
AVIATION...NED
MARINE...BSH
TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service Cleveland OH
922 PM EDT Mon Oct 19 2020
.SYNOPSIS...
A stationary front located on the southeast edge of the area
will remain there through tonight and most of tomorrow and high
pressure builds east across the Great Lakes region. Low pressure
will move northeast across the Upper Great Lakes region Tuesday
night into Wednesday, bringing a warm front across the area
overnight Tuesday and a cold front across the area on Wednesday.
Another low pressure system will impact the area for the
beginning of the weekend.
&&
.NEAR TERM /THROUGH TUESDAY NIGHT/...
930 pm update...
We made some minor adjustments to the precip chances to match
up with trends and latest HRRR guidance. The next round of
widespread light rain is currently developing across the lower
Ohio Valley this evening and will be moving through the local
area later tonight.
Previous discussion...
A stationary front is currently located to the southeast of the
CWA. The widespread shower activity that was associated with
this front moving across the area has mainly diminished, however
the very moist airmass remains stationed with dew points in the
40-50s. Cooler temperatures have resulted in RH values reaching
near 100 percent and foggy conditions developing, which are
expected to persist into the evening/early overnight hours.
Another round of widespread showers is expected to move across
the area this evening into the overnight hours ahead of the
high pressure building in from the west. A vorticity maximum
will aid in providing the lift needed to produce the showers.
As the high pressure builds in, the stationary front will be
pushed further east, allowing showers to finally move out of the
area. In total, areas could see 1-1.25" of rain through Tuesday
morning, especially in central and east-central Ohio. High
temperatures on Tuesday will be in the mid to upper 50s.
The remainder of Tuesday will be cloudy, but dry until the next
low pressure system moves into the Upper Great Lakes Region and
brings a chance of showers to the area overnight Tuesday. Models
are suggesting an increase in instability associated with this
low pressure as well, so isolated thunderstorms cannot be rules
out west of I-71. Overnight lows will occur early in the night
as the warm front moves north of the area and temperatures
begin to increase after sunset.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Westerly to southwesterly flow aloft resides over our CWA through
Thursday night as we are sandwiched between a longwave trough axis
to our west and a longwave ridge axis to our east. At the surface, a
cold front sweeps southeastward across our region on Wednesday as a
low moves northeastward from the Upper Great Lakes to central
Quebec. Scattered rain showers are expected along and ahead of the
front. There may be enough instability for isolated thunderstorm
development, especially west of I-71. High temperatures should reach
the mid 60`s to lower 70`s. Primarily fair weather is anticipated
Wednesday night as a surface high pressure ridge advances eastward
across our area. However, isolated rain showers associated with the
upper-reaches of the departing cold front may affect areas east of I-
71 Wednesday evening. During the predawn hours of Thursday morning,
additional rain showers may form over/near Lake Erie as a return
flow of warm and humid air from the southern Gulf Stream undergoes
isentropic lift aloft. Low temperatures should mainly reach the
50`s.
On Thursday, a surface warm front should move northward and near the
southern shore of Lake Erie by nightfall as a surface low moves
northeastward from the central Great Plains toward the Upper
Mississippi Valley. Primarily fair weather is forecast, but
scattered rain showers may affect Lake Erie and vicinity in
association with the advancing warm front. Thursday will be very
balmy, with afternoon highs expected to reach the 70`s. Fair weather
should grace our entire region Thursday night as the surface warm
front advances farther northward from Lake Erie and vicinity, and a
surface ridge associated with the unusually-warm air mass noses into
our CWA from the south and southeast. Low temperatures should reach
the 50`s to lower 60`s.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
The large-scale weather pattern aloft is not expected to change much
during this period. As a result, southwesterly to westerly mid- to
upper-level flow should persist over our CWA. At the surface, a high
pressure ridge exits eastward slowly on Friday as a cold front
approaches from the west. Isolated to scattered showers and
thunderstorms are possible ahead of the front. Friday will be
another unusually-warm day, with highs reaching the 70`s. The
surface cold front sweeps eastward across our CWA Friday night and
will be accompanied by scattered showers and thunderstorms. Low
temperatures should reach the mid 40`s to lower 50`s as colder air
follows the front.
Odds favor fair weather Saturday through Sunday as a surface high
pressure center moves from the Upper Midwest to southern Quebec and
the associated surface ridge affects our area. Afternoon highs
should reach the 50`s both days. Overnight lows should reach the mid
30`s to lower 40`s Saturday night.
&&
.AVIATION /00Z Tuesday THROUGH Saturday/...
A stationary front is currently position across northern Ohio
which is helping keep the low ceilings and visibilities down for
this TAF update. Widespread IFR to LIFR ceilings will be likely
tonight through Tuesday morning with a gradual improvement to
IFR to some MVFR by late in the TAF period. Closer to the
surface boundary and near the slightly higher terrain of central
Ohio, there could be some areas of fog and lower visibility
around CAK and MFD down to 1/2sm later tonight. Otherwise look
for ceilings between 300 to 700 feet for most of tonight. Light
rain and drizzle will come in waves tonight across the area.
Winds closest to the front will be light and variable. Winds
north of the boundary will be northerly to northeasterly 4 to 8
knots. Modest improvement in ceilings and vis will come towards
late in the TAF period.
Outlook...Non-VFR conditions possible through Wednesday night
with showers.
&&
.MARINE...
Northerly to northeasterly winds of about 10 to 20 knots veer
gradually to easterly by late Tuesday evening as a high pressure
ridge advances eastward over Lake Erie. Waves trend 1 to 3 feet,
but occasional 4 footers are possible between The Islands and
Avon Point overnight tonight. Refrained from issuing a Small
Craft Advisory since any 4 foot waves should be brief.
Easterly winds of about 10 to 20 knots veer to southerly and
then to southwesterly overnight Tuesday night as a warm front
sweeps north over Lake Erie. Waves trend 2 to 4 feet, with the
largest waves in the open waters. Southwesterly winds of about
15 to 22 knots shift to westerly on Wednesday as a cold front
sweeps eastward. Waves should once again trend 2 to 4 feet.
A stronger warm front should lift north across Lake Erie on
Thursday and Thursday night, leading to a window of fairly
stable conditions with light winds and relatively-smaller
waves. A cold front should push eastward across Lake Erie
Friday night with north to northwest flow heading into Saturday
as a high pressure ridge builds from the Upper Midwest.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...None.
&&
$$
SYNOPSIS...Campbell
NEAR TERM...Campbell/Griffin
SHORT TERM...Jaszka
LONG TERM...Jaszka
AVIATION...Griffin
MARINE...Jaszka
Area Forecast Discussion
National Weather Service Green Bay WI
1053 PM CDT Mon Oct 19 2020
Updated aviation portion for 06Z TAF issuance
.SHORT TERM...Tonight and Tuesday
Issued at 250 PM CDT Mon Oct 19 2020
The latest RAP analysis and satellite/radar imagery show high
pressure centered from North Dakota to western Wisconsin early
this afternoon. A large area of clouds exist upstream within a
weak warm advection regime and are slowly spreading across
northeast WI. After a cold start, temperatures are struggling to
warm this afternoon, and remain in the 30s. Besides clouds and
temps tonight, forecast concerns also revolve around wintry
weather impacts when a strengthening system moves into the Great
Lakes on Tuesday afternoon.
Tonight...High pressure will become centered across the state
tonight. Plenty of cloud cover resides upstream, but westerly flow
isn`t particularly strong, so think may see some clearing take
place. But with thermal troughing and light west to northwest flow
off the warmer regional lakes, think clouds may be a little slower
to erode than models indicate. So delayed the clearing trend to
mainly after midnight, but did drop temps a degree or two in the
cold spots thinking that temps won`t need long to fall below
guidance.
Tuesday...After a few hours of sunshine early in the morning,
clouds will rapidly spread across the region from southwest to
northeast. As the right rear quad and warm advection increases in
the mid-levels, will see a band of moderate precip move across the
northern Plains and into northern Wisconsin in the afternoon.
With the arrival of the precip, wet bulb effects will lead to
temperatures falling, enough so that rain mixes with snow by mid-
afternoon and changes to all snow by late afternoon over north-
central WI. Road temperature forecasts suggest ground temps will
lead to a period of melting snow through late afternoon before
snow starts to accumulate on roadways. As a result, may only see
some accumulations on grassy surfaces for a time, which will
likely mitigate potential impacts for the evening commute
somewhat. Will show 1-2" of accumulations over parts of central
and north-central WI by early evening. With coordination from the
long term forecaster below and offices to the west, will start a
winter weather advisory starting at 21z. First snow of the season
plus accumulations on roadways starting during the evening commute
may lead to some travel difficulties.
.LONG TERM...Tuesday Night Through Monday
Issued at 250 PM CDT Mon Oct 19 2020
Active weather pattern in the long- term part of the forecast
with several rounds of precipitation expected. As temperatures
hover near the freezing mark precip- type will also be a factor.
Tuesday night...Precip will be ongoing across the forecast area
at the start of the long-term period, 00Z/Wednesday. Will continue
to see broad lift from the RRQ of one jet streak, which
transitions to the LFQ of the next jet streak, along with
additional forcing from the mid-level shortwave and a sfc low
moving just southeast of the area. Temperature profiles support
all rain across the Fox Valley and east- central WI, mainly snow
across north- central WI, with a transition area in between. A
sharp cutoff in snow is expected from central into northeast WI,
from roughly Wisconsin Rapids to east of Iron Mountain, but this
line could certainly shift a bit. With ample lift, expect to see a
couple hours of steady precip Tuesday evening, during which time
1 to 2 inches of additional snowfall accumulation is forecast in
the areas expecting snow. As the sfc low moves east and drier air
takes over, expect to see a quick end in precip from west to
east. With the loss of moisture aloft (in the DGZ) first, could
also see a brief period of freezing rain across north- central WI
late Tuesday evening and overnight as sfc temps will be right
around freezing.
While confidence in the snow/precip forecast is fairly high due to
the consistency over the past couple days, there does remain some
uncertainty to the extend of the impacts. It is still early in the
season and road temperatures are not as cold as they would be
mid-winter. Regardless, snow amounts do warrant a Winter Weather
Advisory, which has been issued. In total, 2 to 4 inches of snow
are forecast north of a jagged line from Marshfield, to Merrill,
to Antigo, to Iron Mountain, with a dusting to 2 inches just
south of this line.
Wednesday through Friday...Quiet, cloudy, and slightly warmer
weather is expected on Wednesday as this system departs and we
await the next one. Precip chances increase once again late
Wednesday night into Thursday morning as another wave a WAA
pushes into the area. Precip type will initially vary from snow
across north- central WI, rain in east- central WI, with a
transition zone in the middle. As temperatures rise due to daytime
heating precip will transition to all rain. Thunderstorms also
enter the forecast by Thursday afternoon with up to 500 J/kg of
CAPE. Not expecting any severe weather at this time. Precip
continues Thursday night into Friday as the sfc low moves across
the state and the main mid and upper level forcing arrives and
continues to provide ample lift. Precip may change back to snow
or a rain/snow mix across the far north Friday morning or early
afternoon before coming to an end, but for the most part rain will
be the primary precip-type with this system. Conditions dry out
for the second half of Friday.
Saturday and Sunday...Greater uncertainty to towards the weekend
as models show another sfc low strengthening over the Rockies and
ejecting into the Plains. There are differences in the track of
this system with the GFS keeping the bulk of the precip much
farther south, and the EC and Canadian bring precip into WI. Used
a blended model solution which features chance PoPs from Sunday
into Monday. Temperature profiles would once again support of mix
of snow and rain across the forecast area. However, overall
confidence in this period is low and the forecast will need
refinement as the period gets closer.
Temperatures will be the warmest and slightly above normal on
Thursday, with high temperatures in the middle 40s to lower 60s.
The rest of the forecast will generally be at or below normal.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 1053 PM CDT Mon Oct 19 2020
The main aviation concerns for this TAF issuance will be areas
of patchy fog across central Wisconsin overnight, and the arrival
of the next weather system Tuesday afternoon. Clear skies over
AUW, CWA, and RHI will allow for patchy fog development tonight,
with brief visibility restrictions at times. This fog will be
fairly spotty.
Tuesday, VFR conditions will start the day, but clouds and
rain/snow showers will move into the region in the afternoon. The
central sites of CWA/AUW/RHI will see a rapid deterioration of
visibility and cloud deck for any snow showers that develop, as
we head into a period of IFR conditions. Areas further east will
likely see mainly rain, which will keep visibility a bit better.
The active weather will likely continue through the end of the TAF
period for all sites.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 4 PM Tuesday to 1 AM CDT Wednesday
for WIZ005-010>012-018-019-030.
&&
$$
SHORT TERM.....MPC
LONG TERM......KLJ
AVIATION.......Uhlmann
Area Forecast Discussion
National Weather Service Houston/Galveston TX
732 PM CDT Mon Oct 19 2020
.SHORT TERM [Tonight through Tuesday]...
Showers and isolated thunderstorms in the area have dissipated and
focus shifts up to the stationary front just northwest of the CWA
by a county. HRRR is very bullish on development on the boundary
the next 3 to 4 hours...will leave in some slight chances for
showers over the area from Caldwell to College Station to Crockett
this evening but that is probably too generous. Skies should be a
mix of partly cloudy early becoming mostly cloudy to cloudy. Warm
night as WAA pattern remains in place and developing blanket of
stratus helps to trap that heat. Tuesday looking more rain-free
than today was as drier air intrudes and winds back slightly.
45
&&
.AVIATION [00Z TAF Issuance]...
Although it is VFR that will be fairly short lived as SC/ST deck
develops this evening and expands northward. Expecting MVFR
conditions beneath the stratus deck in the 1000-2000 foot range
and highest confidence of MVFR conditions looks to be CXO-66R
northward between 03-09z. The MVFR deck will also likely lower and
near UTS/CLL and dip into IFR at least briefly in the 10-13z
window there. Skies quickly scatter out around 14-15z and VFR
should prevail. Tuesday night looking like we could see some
MIFG/BR starting late in the evening with more favorable
radiational cooling profile.
45
&&
.PREV DISCUSSION /Issued 327 PM CDT Mon Oct 19 2020/...
.LONG TERM (Wednesday through Monday)...
On Wednesday, the upper flow over Texas will be kind of flat as
the region lies on the western periphery of an upper high over the
eastern U.S. and a weak short wave over the western plains. At the
surface, weak low pressure will be over the southern Gulf of
Mexico and this feature will allow for onshore winds to persist.
The air mass will remain humid so can`t rule out an isolated
shower from time to time but the lack of a well defined boundary
and upper level support should keep most areas dry. Not a lot of
day to day change through the end of the week as temperatures
remain 5 to 10 degrees warmer than normal. A weak cold front will
cross SE TX on Saturday but convergence along the front looks weak
and PW values are meager, reaching only around 1.20 inches. Will
keep the fropa dry for now but will watch trends as we near the
end of the week. We should get a brief cool down on Saturday in
the wake of the front with weak CAA but temperatures warm right
back up again on Sunday as onshore winds return. Warm and humid
conditions are expected Sunday and Monday as weak upper level
ridging over the Gulf expands into Texas. Another cold front is
expected to cross SE TX on Tuesday but both the GFS and ECMWF hang
the upper level support to the west so the front will probably be
a slow mover and the Canadian does not bring the front through
until next Thursday. Ensemble guidance also seems to favor the
slower solutions. 43
.MARINE...
High pressure east of the region will allow for an onshore flow
tonight. As weak low pressure develops over the southern Gulf, the
flow between the high to the east and the low will allow for
surface winds to back to the east and an east wind will then
persist into Friday. A cold front will cross the coastal waters
early Saturday and winds will back to the NE. High pressure
building into the southern plains behind the front will move east
very quickly and onshore winds will redevelop by late Saturday
night. Onshore winds will then prevail through early Tuesday.
Water levels could briefly reach 3.5 feet above MLLW on Wednesday
as a persistent east wind brings slightly elevated water levels
to the coast. Tides will probably remain near or just above 3.0
feet at high tide through the end of the week due to the
persistent east wind. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 71 87 68 86 66 / 20 10 0 10 0
Houston (IAH) 71 85 70 86 69 / 20 10 10 10 0
Galveston (GLS) 74 82 74 83 75 / 20 20 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
SHORT TERM/AVIATION...45
MARINE/CLIMATE/LONG TERM...41
Area Forecast Discussion
National Weather Service Wichita KS
651 PM CDT Mon Oct 19 2020
.SHORT TERM...(This evening through Wednesday night)
Issued at 304 PM CDT Mon Oct 19 2020
Broad upper trough remains from the Northern Rockies into the
Great Lakes. At the surface, stationary front is situated down
across south central TX with a surface high over the Upper
Mississippi Valley.
Main theme tonight will be return flow commencing across the
southern Plains allowing rich moisture to stream north. This will
result in low clouds either returning or remaining in place with
drizzle chances picking up late tonight and especially Tue morning
into Tue afternoon as isentropic lift right off the surface
increases. At this time feel that patchy/areas of drizzle will be
more likely tomorrow than light rain. Shortwave energy will swing
across the Northern Plains Tue afternoon with a cold front
surging south across ND/SD/NE but doesn`t look to make it down
into our forecast area.
NAM and GFS currently have big disagreements on how far north the
warmer air makes it on Tue. The GFS lifts the warm front much
further north compared to the NAM with the GFS having some support
from the RAP and ECMWF. So currently have a small lean to temps
being closer to the warmer GFS tomorrow, placing the warm front
across southern KS. Chances for showers and isolated storms will
increase late Tue afternoon into Tue evening as 850mb moisture
transport and convergence ramps up. With an abundance of low
clouds, storms will have to be elevated with models showing around
500-1000J/KG of elevated instability across southeast KS.
Warm front is expected to lift north to around I-70 on Wed as a more
robust shortwave starts to dig across the Northern Intermountain
into the Northern Rockies.
.LONG TERM...(Thursday through Monday)
Issued at 304 PM CDT Mon Oct 19 2020
Good agreement between the ECMWF and GFS in a shortwave trough
swinging across the Northern/Central Plains late Thu afternoon
through Thu night.
Strong southwest winds are expected during the day Thu ahead of
the cold front, with wind advisory speeds likely for much of the
area. Strong cold front is expected to push through Thu night into
early Fri morning. There should be some showers and storms along
the front as it pushes south, but not expecting any decent
widespread rainfall due to the front remaining very progressive.
Following the front looks like one of the coldest airmasses of the
fall season so far, with highs in the 40s for much of the region
on Fri with lows in the 20s for parts of central KS Sat morning.
Below normal temps look to remain in place through the weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 651 PM CDT Mon Oct 19 2020
MVFR cigs will prevail across most of the area tonight with a
period of IFR in southeast Kansas. Patchy drizzle may develop on
Tuesday morning.
KED
&&
.FIRE WEATHER...
Issued at 304 PM CDT Mon Oct 19 2020
Very high grassland fire danger will be likely Thursday afternoon
across much of the area.
Very strong south and southwest winds are expected across much of
the area Thursday afternoon into the early evening. We are looking
at south/southwest winds around 30 mph with gusts 40 to 50 mph. RH
values in the afternoon are forecast to be around 50%. So the main
driver for very high grassland fire danger will be the strong
winds.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 41 60 50 74 / 10 20 30 20
Hutchinson 40 59 45 69 / 0 10 20 20
Newton 40 58 47 71 / 0 20 20 20
ElDorado 40 59 50 73 / 10 20 30 20
Winfield-KWLD 42 62 55 78 / 10 20 40 10
Russell 36 59 41 59 / 0 10 0 30
Great Bend 37 61 42 62 / 0 10 10 20
Salina 38 57 42 64 / 0 10 10 30
McPherson 39 58 43 67 / 0 10 20 20
Coffeyville 44 64 57 78 / 20 30 40 10
Chanute 41 61 53 75 / 10 30 40 20
Iola 41 60 51 75 / 10 30 40 20
Parsons-KPPF 43 63 56 76 / 10 30 40 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
SHORT TERM...RBL
LONG TERM...RBL
AVIATION...KED
FIRE WEATHER...RBL
Area Forecast Discussion
National Weather Service Melbourne FL
959 PM EDT Mon Oct 19 2020
.UPDATE...
Very minor changes this evening, as the forecast remains on track.
Isolated to scattered showers continuing to drift onshore as of
945pm this evening, though overall coverage has diminished. A few
lightning strikes have been noted offshore from the Treasure
Coast, but any thunderstorm activity should taper off by midnight.
However, showers will continue, with the HRRR supporting
maintaining a 30-40% chance of showers along the Treasure Coast
through the overnight, with isolated showers further northward.
Robust steering flow winds of 15-20mph will keep showers from
persisting over one area. Highest chances will be along the coast,
but a couple of heavier showers could persist long enough to make
it to the Orlando metro area. Easterly flow persisting overnight,
with winds up to 15mph along the coast and less than 10mph
inland. Winds off of the warm Atlantic waters will keep overnight
lows well above normal, in the mid 70s across the interior and
approaching the upper 70s along the coast.
&&
.AVIATION...
ISO-SCT SHRA will continue to push west in breezy, moist east flow
overnight, providing coastal terminals with brief reductions in
CIGs/VSBYs. Otherwise, VFR most areas with NE winds 10-15 knots
along the coast and less than 10 knots interior. On Tue, wind veers
more Easterly and pressure gradient will support 12-15 knots with
gusts 20-22 knots esp at the coast. There will be SCT SHRA pushing
onshore so have added VCSH to most terminals.
&&
.MARINE...
Breezy onshore flow continuing overnight, with persistent
hazardous boating conditions. Easterly winds 15-20kts, with
isolated to scattered showers pushing onshore. Highest chances
will be along the Treasure Coast and any thunderstorm activity is
expected to diminish by midnight. Seas will remain elevated up to
6-7ft, especially offshore. A Small Craft Advisory is in effect
for most of our Atlantic marine zones, while Small Craft Should
Exercise Caution in the nearshore waters from Flagler Beach to
Sebastian Inlet.
&&
.HYDROLOGY...
The Saint Johns River at Astor is forecast to remain in Minor Flood
Stage, just below Moderate Flood, this week. Elsewhere, the Saint
Johns River at Sanford and above Lake Harney, is forecast to stay
within Action Stage, while at DeLand the river is forecast to remain
just below Action Stage. Refer to daily Flood Statements from NWS
Melbourne for the latest river levels and forecasts.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 74 85 73 82 / 30 30 40 50
MCO 74 85 74 82 / 30 40 40 50
MLB 77 85 75 82 / 30 40 50 60
VRB 76 86 75 84 / 40 40 50 60
LEE 73 86 73 82 / 20 40 20 50
SFB 74 85 74 82 / 30 40 40 50
ORL 76 87 75 83 / 30 40 30 50
FPR 75 84 74 82 / 40 50 60 60
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...Small Craft Advisory from 8 PM Tuesday to 8 PM EDT Wednesday for
Flagler Beach to Volusia-Brevard County Line 0-20 nm-
Volusia-Brevard County Line to Sebastian Inlet 0-20 nm.
Small Craft Advisory until 8 PM EDT Wednesday for Flagler Beach
to Volusia-Brevard County Line 20-60 nm-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.
&&
$$
Leahy/Volkmer/Kelly
Area Forecast Discussion
National Weather Service Paducah KY
949 PM CDT Mon Oct 19 2020
.UPDATE...
Issued at 949 PM CDT Mon Oct 19 2020
The front is stalled out over the southern Pennyrile, and little
movement is expected overnight. Persistent low-level warm
advection has forced a band of showers with an occasional
thunderstorm mixed in. The current activity is right along the
Ohio River, and latest HRRR output pushes this area slowly
southeast through west Kentucky through daybreak. There also
should be a modest decrease in coverage by morning. Updated PoPs
to account for the expected trends.
Individual showers are moving fast enough to alleviate any
significant flooding concerns despite some training.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 249 PM CDT MON OCT 19 2020
The front is currently stalled along a Clarksville TN to Central
City KY line. A new wave of showers has reached the Mississippi
River and push eastward at a rapid pace. Showers moving across the
area, however, thunderstorms are forming down in Arkansas.
Tonight, the front is expected to slowly push north, reaching a
New Madrid MO to Owensboro KY line by Midnight or so with very
little movement the rest of the night. This front will be the main
focus for showers and Thunderstorms tonight. Another 1 to 1.5
inches of rain possible. Rapid changes tomorrow as the front lifts
or redevelops to our north and west by 00Z Wed. As the front
lifts/dissipates the chances for showers will dissipate too. This
will also bring a dramatic warmup.
The front will then lay back down near our northern counties
Tuesday night bringing a small chance of showers and storms to
that area.
In the upper levels, the flow is generally zonal across the Plains
lifting up to a ridge off the east coast. The surface front is
generally parallel to the flow through early Tuesday. Heights rise
slightly during the day tomorrow, allowing the front to move/re-
develop to our north. The next shortwave moving through the flow
will push the front south Tuesday night.
Used the HREF ensembles for thunder placement tonight and
tomorrow. The MUCAPE axis lines up parallel to the front most of
the night. 0-6 km bulk shear vectors are at 30-35 kts, but lapse
rates are poor for any severe convection. The warm cloud layer
will be more than 10k ft so efficient rainfall processes will
continue. Precipitable water values range from 1 to 2 inches
depending upon the model. Locally heavy rainfall possible again
tonight.
.LONG TERM...(Wednesday Through Monday)
ISSUED AT 311 PM CDT MON OCT 19 2020
By Wednesday, our front will have lifted farther north of our
region, and we will have dry conditions and gradually decreasing
cloud cover. South winds will bring temperatures back up to well
above normal readings in the middle 70s to around 80 degrees. By
Thursday, southerly flow will be increasing across the middle
Mississippi and lower Ohio valleys ahead of an approaching cold
front. We should see lots of sunshine and even warmer highs in the
lower 80s across the PAH forecast area. South winds will keep our
overnight lows well above normal, with lows Wednesday night in the
upper 50s to around 60 degrees, and Thursday night mostly in the
lower 60s.
By 12z Friday, models show the cold front extending from northern
Illinois through south central Missouri. The front will move east
of the PAH forecast area by 06z Saturday. Showers and a few
thunderstorms will be possible across the entire area Friday
morning, with the best chances Friday afternoon, then convective
activity will decrease from west to east Friday evening.
Highs temperatures will remain above normal for Friday, with highs
in the middle to upper 70s. Temperatures will be significantly
cooler behind the front, with lows Friday night from the lower to
middle 40s west to around 50 degrees east.
Some of the latest model runs hints at the front hanging up just
southeast of our region, but models blends keep us dry and cool
through the weekend. We went with dry conditions through Sunday,
with well below normal temperatures Saturday,moderating to just
below normal by Sunday. Models bring another front into the region
Sunday night and Monday, bringing back chances of showers.
&&
.AVIATION...
ISSUED AT 605 PM CDT MON OCT 19 2020
Widespread ifr and lifr conditions will continue through Tuesday
morning on the north side of a stalled front. Isolated thunderstorms
this evening will affect primarily the kowb taf site. Otherwise,
most of the precip will be in the form of light rain and drizzle.
The front will make significant northward progress as a warm front
on Tuesday. As the front passes, improvement to mvfr conditions is
expected in the afternoon. Winds will turn into the southeast to
south around 5 kt after the front passes.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...DRS
SHORT TERM...PS
LONG TERM...RST
AVIATION...MY
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
826 PM EDT Mon Oct 19 2020
.UPDATE...
Most of west central and southwest Florida saw some rainfall today
and even a few storms for some areas. A majority of the region saw
less than a quarter of an inch, but some areas in the heavier
showers received between 0.50 - 0.75 inches of rainfall this
afternoon. Shower activity has decreased over the past couple of
hours, with isolated showers remaining over southwest Florida.
Showers and storms are likely once again tomorrow with the highest
coverage over southwest Florida. A high temp record was recorded at
Tampa International Airport hitting 90 degrees. Temperatures will
continue to be on the warm side coming in around 4-6 degrees above
average on Tuesday. Made some slight adjustments to POPs over
southwest Florida based on latest radar coverage and HRRR guidance.
All other parameters look good for now.
&&
.AVIATION...
VFR conditions expected at all terminals through the period. East-
northeast winds 10 knots or less expected overnight, with further
increasing winds to around 15 knots with higher gusts on Tuesday
afternoon. Scattered showers and isolated storms expected on Tuesday
afternoon, so will hold VCTS after 18Z for all terminals during that
time.
&&
.MARINE...
Interaction between a trough of low pressure south of Florida and
strong high pressure over the eastern seaboard will continue to
produce gusty east-northeast winds over the gulf coast waters over
the next couple of days. This has warranted the issuance of a Small
Craft Advisory for eastern gulf waters beyond 20nm from Bonita Beach
to Suwannee River through Tuesday morning and will likely be
extended during the full overnight forecast package. Scattered
showers and isolated storms will be possible once again on Tuesday
afternoon, especially over the southern gulf waters west of
Charlotte Harbor.
&&
.Preliminary Point Temps/PoPs...
TPA 74 87 74 82 / 10 40 20 60
FMY 75 84 74 84 / 30 60 40 70
GIF 74 86 73 82 / 20 40 20 60
SRQ 75 87 74 84 / 20 50 30 70
BKV 72 87 72 84 / 10 40 20 50
SPG 76 86 75 82 / 20 50 30 60
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...None.
Gulf waters...Small Craft Advisory until 8 AM EDT Tuesday for Waters from
Bonita Beach to Englewood FL out 20 to 60 NM-Waters from
Englewood to Tarpon Springs FL out 20 to 60 NM-Waters from
Tarpon Springs to Suwannee River FL out 20 to 60 NM.
&&
$$
UPDATE/AVIATION/MARINE...74/Wynn
DECISION SUPPORT...09/Rude
Area Forecast Discussion
National Weather Service Topeka KS
1020 PM CDT Mon Oct 19 2020
.SYNOPSIS...
Issued at 330 PM CDT Mon Oct 19 2020
Broad, low-amplitude upper troughing was indicated was indicated on
recent water vapor imagery over the bulk of the CONUS. A ridge of
high pressure was centered over the Upper Midwest per 19Z obs with
generally light east winds over eastern Kansas. Some breaks in the
stratus have been noted across northern and western Kansas though
identification of these is somewhat difficult under areas of cirrus.
An area of modest isentropic upglide around 750 mb in deeper
moisture allowed for spotty showers to brush the southern counties
this morning and lower ceilings remain in place in southeast
Kansas.
&&
.UPDATE...
Issued at 1020 PM CDT Mon Oct 19 2020
The 18Z RAP and NAM where showing a signal for some drizzle
developing towards 12Z due to weak isentropic lift increasing
within the stable saturated layer of the stratus deck. More recent
solutions from the models continue to show this possibility. So
have inserted a mention of patchy drizzle across east central KS
beginning around 12Z and bridging to the chance POPs that were in
the afternoon from the prev forecast.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 330 PM CDT Mon Oct 19 2020
The surface ridge nudges east tonight with winds containing a
southerly component deepening and pushing east with time. Expect this
to result in an overnight increase and lowering of stratus, and in
combination with continued areas of cirrus, keep diurnal cooling
tempered, and have leaned on the warmer side of guidance for low
temps. Some patchy frost is hard to rule out in northern areas where
some breaks in the cloud have occurred though some modest winds
should persist through the night.
A shortwave digs southeast into the northern High Plains late
tonight and crosses the northern Plains Tuesday. Southerly flow
deepens to the surface by midday though have concerns about stratus
persistence for how high temps will get and sided on the cooler end
of temps here. Modest mid-level troughing passes through and will
keep some mention of precip in eastern areas where deeper moisture
exists.
.LONG TERM...(Tuesday night through Monday)
Issued at 330 PM CDT Mon Oct 19 2020
The cold front associated with the northern wave pushes through
Tuesday night, though settling in southern Kansas with continued
strong flow aloft to the north. Showers and perhaps some
thunderstorms may become more widespread in southeastern locations
in the evening but may spread farther north late in the night into
much of Wednesday as warm-air advection returns rather quickly. Have
little confidence in timing and placement of this activity however
with models diverging on moisture depths and isentropic setups. This
lower confidence spreads into temps for Wednesday but have trended
down a bit. Next few periods showing an even more active regime as a
stronger shortwave comes through the pattern with a similar path of
the Tuesday wave. Strong south-southwest winds take hold by Thursday
morning with a stout low-level jet preceding to bring warming temps
overnight and a quite warm and windy Thursday with temps back in the
80s quite likely. The cold front surges through late Thursday into
Thursday night for the highest precip chances of this period. Severe
threat doesn`t appear too high at this point with unfavorable shear
profiles. Another quite cold airmass comes in behind (sourced in
northwest Canada) with a decent chance for a widespread freeze
Friday night. The next shortwave in this persistent pattern brings
the next chance for precip Sunday into Monday with more cold temps
following.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday)
Issued at 603 PM CDT Mon Oct 19 2020
Latest guidance from the NAM and RAP is suggesting CIGS could
remain VFR for a good portion of the evening before lowering back
below 3KFT. Timing the CIGS will be the main challenge. There is
also a signal for some -DZ to develop early Tue morning. Will
monitor trends before jumping on this since none of the guidance
is showing restricted VSBY. Think low clouds should scatter out by
mid afternoon with any precip remaining southeast of the
terminals where the better instability should set up.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Wolters
SYNOPSIS...65
SHORT TERM...65
LONG TERM...65
AVIATION...Wolters