Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/25/18
Area Forecast Discussion
National Weather Service Albany NY
1028 PM EDT Mon Sep 24 2018
.SYNOPSIS...
Widespread rainfall will overspread the area late tonight and
continue through much of Tuesday with the rain coming down heavy
at times. Expecting a lull in the rain Tuesday night with
showers and embedded thunderstorms expected Wednesday into
Wednesday evening as a cold front approaches and moves through.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
As of 1028 PM EDT...IR satellite imagery continues to show
clouds increasing in coverage across the area, as a warm front
over the Ohio Valley and central Appalachians approaches. It
remains dry for now, as the nearest rainfall is currently over
far western New York and Pennsylvania. 3km HRRR suggest rainfall
will begin across far southern areas by 3 to 4 AM and will move
northward across the rest of the area by sunrise. The rain will
start to pick up in intensity towards daybreak, especially for
areas south and west of the Capital Region.
Although most valley areas will be seeing light winds through
the night, high terrain areas (especially in western New
England) will see increasing winds by late in the overnight,
especially towards daybreak. Some E-SE winds will be gusting
over 25 kts by daybreak Tuesday in favored areas of the
Taconics, Greens and Berkshires.
Initially temperatures will fall this evening however then they
should become steady for much of the overnight. Expecting lows
in the lower to mid 50s in the Hudson Valley from the
Poughkeepsie areas northward into the Capital District and
across northwestern Connecticut with 40s across the rest of the
forecast area.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Rain heavy at times Tuesday especially during the morning as a
warm front approaches and lifts through. The bulk of the rain
is expected to occur between 6 am and noontime. Once the warm
front moves to our north the steady rain will taper off to
showers by late in the day into the evening. The heavy rain may
cause localized flooding of urban, low lying, poor drainage
areas and small creeks. A lull in the rain is expected in the
warm sector Tuesday night and have pops decreasing to low
chances for the overnight hours.
Strong and gusty southeastern winds will occur across the
higher terrain of the Taconics, southern Green Mountains,
Berkshires, as well as the eastern Catskills and southern
Adirondacks Tuesday morning. Expecting gusts in the 30s with
some into the lower to possibly mid 40s. A strong low level
inversion should keep stronger winds from mixing to the surface.
A few downed tree limbs may cause some isolated power outages.
With the widespread rainfall Tuesday temperatures will be below
normal with highs only rise into the mid 50s to mid 60s. However
Tuesday night in the warm sector temperatures are not expected
to drop off but rise into the lower to upper 60s.
Showers with embedded thunderstorms are expected Wednesday as a
cold front approaches and moves across the region. The Storm
Prediction Center as the region in a slight risk for severe
thunderstorms in their Day 3 Outlook. The potential for strong
to severe storms will be dependent on the amount of instability
that occurs and if we can get any sunshine. The better chances
for greater instability will be to the southeast of the Capital
District. The threat is for strong to damaging wind gusts from
thunderstorms. With precipitable water values 1 1/2 to 2 inches
in the warm sector ahead of the cold front thunderstorms will be
capable of localized very heavy rainfall so localized urban and
low lying flooding is possible especially for locations that
receive heavy rain Tuesday. Will be warm and humid/muggy with
highs mainly in the 70s with near 80 degrees in the mid Hudson
Valley.
With the passage of the cold front Wednesday night winds will
shift to the west-northwest and a cooler and much less humid air
mass will be ushered into the region. Lows are eventually
expected to drop into the lower 40s to mid 50s by sunrise
Thursday.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
The long term forecast period will begin with high pressure over
head and dry weather. Chances for rain will increase over the region
this weekend into early next week.
Surface high pressure will slowly translate eastward over the region
Thursday into the early weekend. This will keep the tangible weather
conditions dry. Skies will likely remain partly to mostly cloudy as
forecast soundings suggest a pretty moist column throughout the
upper atmosphere. There is a small chance that a weak moisture-
starved piece of energy slides over our northern zones Friday night
bringing some isolated showers to the Adirondacks but confidence is
too low to include any PoPs at this time. High temperatures will
generally be in the 60s with the higher terrain possibly staying in
the upper 50s and valley locations maybe creeping into the lower 70s
Thursday through Saturday.
A cold front will approach the region from the west during the
latter part of the weekend with an additional low pressure system
right on its heels. Rain showers will be possible on Sunday and
Monday but confidence of intensity and placement are low at this
point. Temperatures will continue to be seasonable with highs in the
upper 50s over the higher terrain to upper 60s over valley
locations. Lows temperatures throughout the entire long term period
will be in the mid 40s to mid 50s.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
With a warm front approaching, clouds will be on the increase
this evening and most sites will be lowering to MVFR cigs
around 2-3 kft by around midnight or so. Some light rain will
begin by late in the overnight. Rain will pick up in intensity
after daybreak, with IFR conditions for most sites for
visibility during Tuesday morning. Although visibility may
improve on Tuesday afternoon, as the heaviest rain shifts away
from the area, lingering light rain and low clouds will keep
MVFR/IFR conditions into the afternoon hours for all sites.
Winds will be increasing overnight from a southeast direction at
5-10 kts. The strongest winds will be at KALB/KPSF, where some
higher gusts are possible, especially on Tuesday morning. Winds
will mainly be south on Tuesday around 10 kts through the day. 2
kft winds will be around 35-40 kts on Tuesday morning as well,
but enough of a surface wind should help prevent LLWS from
occurring. If surface winds are lighter than expected, LLWS may
be needed to be added to future issuances of the TAFs
Outlook...
Tuesday Night: Moderate Operational Impact. Chance of SHRA.
Wednesday: High Operational Impact. Breezy Definite SHRA...TSRA.
Wednesday Night: Moderate Operational Impact. Chance of SHRA.
Thursday: No Operational Impact. NO SIG WX.
Thursday Night: No Operational Impact. NO SIG WX.
Friday: No Operational Impact. NO SIG WX.
Friday Night: No Operational Impact. NO SIG WX.
Saturday: No Operational Impact. NO SIG WX.
&&
.FIRE WEATHER...
Widespread rainfall will overspread the area late tonight and
continue through much of Tuesday with the rain coming down heavy
at times. Expecting a lull in the rain Tuesday night with
showers and embedded thunderstorms expected Wednesday into
Wednesday evening as a cold front approaches and moves through.
&&
.HYDROLOGY...
Widespread rainfall will overspread the area late tonight and
continue through much of Tuesday with the rain coming down heavy
at times especially during the morning hours. Expecting 1 to 2
inches of rain late tonight through Tuesday with the bulk of
that occurring between 6 am and noontime Tuesday.
Expecting a lull in the rain Tuesday night with only some light
QPF expected. Showers and embedded thunderstorms are expected
Wednesday into Wednesday evening as a cold front approaches and
moves through. The heaviest rainfall is expected northwest of
the Capital District across the western/southern Adirondacks
and western Mohawk Valley with around an additional inch.
Otherwise an additional 1/2 inch is expected.
Periods of heavy rain may cause localized flooding of urban, low
lying, poor drainage areas and small creeks on Tuesday. Some
additional showers may also cause localized urban and low lying
flooding on Wednesday as well, especially for locations that saw
heavy rain on Tuesday.
Dry weather is then expected Thursday into the weekend.
For details on specific area rivers and lakes, including
observed and forecast river stages and lake elevations, please
visit the Advanced Hydrologic Prediction Service /AHPS/ graphs
on our website.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...IAA
NEAR TERM...IAA/Frugis
SHORT TERM...IAA
LONG TERM...Cebulko
AVIATION...Frugis
FIRE WEATHER...IAA
HYDROLOGY...IAA
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
713 PM CDT Mon Sep 24 2018
.DISCUSSION...Updated for latest aviation discussion below.
&&
.AVIATION...The conv from earlier this afternoon that affected the
lower TX coastal counties has dissipated and has left behind an
outflow boundary that is pushing steadily westward towards Zapata
County. Although the latest LAPS CAPE values show a pocket of
values >3000 J/KG over the southernmost counties, this instability
is pretty worked over and will likely drop off later this evening
due to the impact of the stable outflow and the loss of the
daytime heating. The daytime heating and the possibility of
another sea breeze boudnary tomorrow may produce another round of
spotty conv. Accordingly will include a mention of VCSH for all
three RGV airports tomorrow afternoon. But do not expect
signficant reductions to ceilings or vsbys throughout the next 24
hours.
&&
.PREV DISCUSSION... /issued 259 PM CDT Mon Sep 24 2018/
SHORT TERM (Now through Tuesday Night): KBRO doppler radar shows
isolated heavy showers over the southeast corner of the BRO CWFA.
Visible outflow boundaries from this convection will likely
produce additional showers and possible thunderstorms through the
next few hours, as suggested by the HRRR model. In fact, a weak
500 mb trough over the northwestern and western Gulf of Mexico
will aid in generating isolated showers and thunderstorms for most
to all of Deep South Texas and the Rio Grande Valley during the
forecast period. Temperatures are expected to rebound to above
normal levels for the first few official days of Autumn.
LONG TERM (Wednesday through Monday): Global models appear to be
better in agreement today compared to yesterday as the
positively-tilted 500mb longwave trough across the central United
States Wednesday bringing a weak cold front into north Texas
Wednesday morning and into south Texas Thursday morning before
stalling. Moisture will pool along and ahead of the frontal
boundary and rain chances will increase across the CWA Wednesday
into Wed night and showers and thunderstorms will develop across
the northern ranchlands Wed night and the rest of deep south Texas
Thursday. Low to mid level moisture will remain high across south
Texas through the rest of the week into the weekend and a chance
of showers and thunderstorms will continue Friday through Sunday
as a 500mb low/inverted trough develops across southwest Texas.
Rain chances should diminish towards the end of the forecast
period as the 500mb ridge across the eastern Gulf of Mexico builds
westward into south Texas Monday.
MARINE (Now through Tuesday Night): Buoy 42020 reported south-
southeast winds around 6 knots gusting to around 8 knots with seas
slightly under 1.5 feet with a period of 8 seconds at 1350 CDT/1850
UTC. Surface high pressure will become the dominant force over the
western Gulf of Mexico during the forecast period, producing
favorable marine conditions along the Lower Texas Coast with light
to moderate winds and low to moderate seas.
Wednesday through Saturday...Light southeast winds will prevail
across the coastal waters Wednesday as a weak cold front moves
into central Texas. Winds are expected to back to the east and
possibly northeast Thursday as the front moves into south Texas
and stalls. The pressure gradient will remain weak across the
lower Texas coast through the rest of the week into the weekend.
Light southeast winds will prevail across the coastal waters
Friday through Saturday.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
This product is also available on the web at:
HTTP://WEATHER.GOV/RGV
Short Term/Aviation...60
Long Term...62
Graphicast/Upper Air...65/67
Area Forecast Discussion
National Weather Service Cheyenne WY
854 PM MDT Mon Sep 24 2018
.UPDATE...
Issued at 847 PM MDT Mon Sep 24 2018
Allowed the current Red Flag Warning to expire on time at 8PM this
evening. After a brief lull in winds and humidity Tuesday, looks
like winds again increase Wednesday that will continue into
Thursday. Warmer temperatures with afternoon humidity below 15
percent Wednesday and Thursday. SO decided to issue a Fire Weather
Watch for Wednesday. Updates have been sent.
&&
.SHORT TERM...(Tonight through Wednesday night)
Issued at 215 PM MDT Mon Sep 24 2018
Upper shortwave will swing east through the CWA overnight with showers
and a few evening storms ahead of it, mainly over the plains. A cold
front will also move across and with clearing skies and lighter winds,
should see temperatures fall into the 30s over western parts of the
CWA by morning. Any lingering showers will move out early Tuesday
morning as the shortwave departs to the east, leaving a mild and dry
day in its wake. A cool surface high settles down the high plains Tuesday
night. Light winds and clear skies will allow minimum temperatures to
plummet into the upper 20s and 30s. Dry and warmer Wednesday as return
flow sets up, with clear and not as cool conditions Wednesday night.
.LONG TERM...(Thursday through Monday)
Issued at 215 PM MDT Mon Sep 24 2018
Northwest flow aloft backs Thursday backs to southwest Saturday as
eastern Pacific upper low moves ashore over northern CA. The upper
low transitions to an open wave over ID/NV Sunday and quickly moves
ENE across MT/WY and northern Great Plains by Monday morning.
Surface high pressure ridge over central Rockies will give way to
approaching cold frontal surge from the north Thursday. Front makes
it as far south and west as the Laramie Range, with the cooler
temperatures lagging well behind the front. Scattered post-frontal
showers will generally remain north of a Douglas-Alliance line. High
temperatures Friday will range from the mid 50s NE to lower 70s SW.
Front slowly retreats NE as a warm front this weekend with warmer
temperatures and increasing southerly winds. Isolated showers will
be possible over the plains Sunday night in advance of the upper
trough.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 515 PM MDT Mon Sep 24 2018
Lowering conditions later this evening as northeasterly upsloping
winds look to be pretty common over the northern Nebraska
Panhandle. HRRR supports this forecast and followed guidance on
timing and locations of lower ceilings.
&&
.FIRE WEATHER...
Issued at 200 PM MDT Mon Sep 24 2018
A cold front will move across the districts this evening with scattered
showers and a few evening storms mainly over the plains. A break from
the critical fire conditions is expected Tuesday with cooler temperatures
and lighter winds. Concerns then increase out west on Wednesday with
the return of warmer temperatures and increasing winds.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Fire Weather Watch from Wednesday afternoon through Wednesday
evening for WYZ301>309.
NE...None.
&&
$$
UPDATE...GCC
SHORT TERM...RE
LONG TERM...MAJ
AVIATION...GCC
FIRE WEATHER...RE
Area Forecast Discussion
National Weather Service Dodge City KS
1100 PM CDT Mon Sep 24 2018
...Updated Aviation...
.SHORT TERM...(This evening through Tuesday)
Issued at 1220 PM CDT Mon Sep 24 2018
Main highlight in the short term will be a strong cold front
moving through the forecast area Tuesday morning from 6 am
through noon...which will provide gusty winds, post frontal
stratus, and some spotty sprinkles and light rain showers.
Tonight a weak stationary front will be in place across western
Kansas roughly from WaKeeney to Hugoton and will be the area
separating the drier air from the northeast winds with the
slightly more moist airmass that will have southeast winds all
night. Latest NAM models have CAPE values roughly around 1000 j/KG
and some wind shear...but at this point kept thunderstorms out of
the forecast. There will be decent isentropic lift ahead of the
front so certainly light rain showers will be possible as the post
frontal stratus moves in. The post frontal stratus should not
last long as breaks in the clouds will start to appear around noon
and clearing continues into the afternoon.
Once the front moves through latest HRRR models have wind gusts
over 40 kts with sustained winds 25-35 kts...so went ahead and
bumped up wind speeds at the time and shortly after the front
moves through. Winds will stay strong through the mid afternoon
before an area of high pressure starts moving in and winds
decrease Tuesday night.
.LONG TERM...(Tuesday night through Monday)
Issued at 203 PM CDT Mon Sep 24 2018
High pressure moves into north central Kansas Tuesday night and
with decent cold air advection lows could drop into the low 40s
for the north central portions of the forecast area. Light east to
southeast winds may be enough upslope to develop some stratus
clouds in the southwest corners which would keep temperatures from
falling as much.
Winds will change back to the southwest through the day on
Wednesday into Thursday introducing a slow warming trend in the
forecast with mainly quiet conditions.
Friday and Saturday will introduce an iffy temperature forecast.
A cold/stationary front roughly from Hays to Syracuse could bring
temperatures only in the 60s on the north side and highs in the
low to mid 80s on the south side. There doesn`t seem to be any
indication of much upper level forcing so the chance of
precipitation looks low at this point. Sunday the front will lift
north as a warm front bringing back mainly 80s across the region
and winds could certainly turn gusty in the afternoon.
Early indications from the newest GFS and Euro trends have a
strong cold front coming in Monday with decent moisture which
could introduce the chance of thunderstorms given the good
baroclinic zone and upper level forcing. Given it is going into
early October and it is 7 days out...kept precip mainly as rain
however it will be the biggest chance of rain/storms in the
foreseeable future.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1100 PM CDT Mon Sep 24 2018
Increasing mid level clouds and light winds are expected for the
next few hours. A strong cold front will arrive at the airports
around 12z Tue, followed by a few hours of post-frontal MVFR
stratus. Expect the lowest and most persistent cigs (and perhaps a
passing brief -SHRA) at HYS, and the highest cigs at LBL. Stratus
will not last long, with subsidence clearing the sky areawide by
18z. An intense pressure gradient during the 15-18z Tue time frame
will produce strong north winds, gusting to near 40 kts. N/NE
winds will relax quickly this afternoon, especially after 21z, as
surface high pressure builds in.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 60 70 47 69 / 10 20 10 0
GCK 57 70 46 68 / 10 20 10 10
EHA 56 70 49 69 / 0 10 10 0
LBL 56 71 49 69 / 0 20 10 0
HYS 61 69 43 69 / 20 30 0 0
P28 63 72 50 70 / 0 20 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Tatro
LONG TERM...Tatro
AVIATION...Turner
Area Forecast Discussion
National Weather Service Green Bay WI
1053 PM CDT Mon Sep 24 2018
Updated aviation portion for 06Z TAF issuance
.SHORT TERM...Tonight and Tuesday
Issued at 250 PM CDT Mon Sep 24 2018
The latest RAP analysis and satellite/radar imagery show a cold
front moving east across Minnesota early this afternoon and high
pressure extending south over the east coast. A band of rain is
occurring behind the front, while eastern MN is dry ahead of the
boundary. Southeast winds are transporting low level moisture into
the southern and central Great Lakes with some the stratus already
pushing into southeast WI. Morning cloud cover has evolved into a
cu field over northeast WI early this afternoon. But as moisture
from the south and the cold front approaches from the west, precip
chances and cloud cover are the main forecast concerns.
Tonight...Eastward moving trough over the northern Plains will
push the cold front across western WI and into central and north-
central WI after midnight. A chance of showers will arrive over
the north along and behind the front. Although there is no
thunderstorm activity along the front early this afternoon, the
NAM does show some elevated instability late tonight, so will
leave a slight chance of thunder in the forecast. Meanwhile, over
eastern WI, a low stratus will likely push into most of eastern WI
from the southeast, though no precip is expected through late
tonight. Due to the clouds and south winds, temps will continue
their warming trend. Lows ranging from the low to upper 50s at
most locations.
Tuesday...The front will slow down as it moves into eastern WI
during the afternoon. Shower activity will likely be more isolated
to scattered in nature along the boundary during the morning.
However, forcing via upper divergence, relatively potent
shortwave, and mid-level fgen all increase in the afternoon. As a
result, most short range models bring a pretty good swath of qpf
across the region that could bring a quarter to a half inch of
rainfall. As a wave of low pressure travels along the front into
eastern WI in the afternoon, the nam brings in 500-800 j/kg into
areas south of Oshkosh to Kewaunee. Not sure if this sort of
instability could develop given the widespread cloud cover that is
anticipated. But if enough heating occurs, could see a few strong
storms develop since 0-6km deep layer shear will reach up to 50
kts.
.LONG TERM...Tuesday Night Through Monday
Issued at 250 PM CDT Mon Sep 24 2018
Low pressure lifting northeast along a cold frontal boundary will
track from eastern WI to southeast Ontario Tuesday evening. The
deformation zone with this system is expected to bring significant
rain to northeast WI during the evening, so pops have been
increased to categorical. Scattered thunderstorms will be possible
in the Fox Valley and lakeshore areas during the early evening.
Precipitation will taper off in the wake of the system overnight,
with gusty northwest winds developing in the Fox Valley and
lakeshore areas. A small craft advisory may be needed Tuesday
night into early Wednesday.
Another cold front is forecast to arrive late Wednesday night
into Thursday, along with the next chance of showers. Models
show little instability with this system, but mid-level lapse
rates around 6.5 C/KM and a short-wave trough may trigger a few
storms over far northern WI Thursday afternoon.
High pressure may bring a brief dry period for the end of the
work week, but models disagree on the arrival time of
precipitation for the weekend. The ECMWF model brings a chance
of rain Friday afternoon and evening, while the GFS is slower
(Friday night into Saturday), so confidence is low in the
details. Saturday night and Sunday morning should be dry as
high pressure tracks through the region.
Will need to keep an eye on Friday night and Saturday night, as
forecast lows are cold enough to be concerned about frost
potential. However, sky cover and wind will play a significant
role in whether or not frost forms, and it is too far out to
ascertain those details.
Low pressure will track south of the region Sunday night into
Monday, and significant isentropic lift/overrunning is anticipated
across the forecast area, so this period looks cool and wet.
Temperatures will be below normal for all of the extended period.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 1050 PM CDT Mon Sep 24 2018
Low clouds will generally be the rule at each of the
TAF sites through much of this TAF period. Generally expecting
MVFR to IFR ceilings into the day Tuesday, although LIFR
conditions are not out of the question at times late tonight into
Tuesday morning. Otherwise, the chances for showers will increase
overnight through the day Tuesday. There could also be some TSRA
by Tuesday afternoon, mainly impacting GRB, ATW and MTW. Winds
will shift from the south to the west and northwest after a cold front
passes and will be gusty in the afternoon. &&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......Kieckbusch
AVIATION.......Cooley
Area Forecast Discussion
National Weather Service Grand Rapids MI
1139 PM EDT Mon Sep 24 2018
LATEST UPDATE...
Aviation
.SYNOPSIS...
Issued at 134 PM EDT Mon Sep 24 2018
A storm system will pass to the east of Southwest Michigan
tonight. It will bring scattered showers and slight chance of a
thunderstorm. Tuesday will see the first system move out of the
area only to have a strong cold front head our way for early
Wednesday morning. This will bring scattered mostly afternoon
thunderstorms to the area with a slight chance of strong
thunderstorms. Showers and scattered thunderstorms are expected
Tuesday night, just ahead of the cold front. It will be warmer
tomorrow, even with all the clouds, highs should get into the mid
70s.
For the rest of the week into the weekend Wednesday and Thursday
will be significantly cooler with highs in the 60s and lows in the
mid to upper 30s north to mid 40s south. Over the weekend a front
is expected to stall just south of there. That is likely to bring
several days of rain and possibly a few thunderstorms. It is
expected to be chilly then, highs may only get into the mid 50s
due to the clouds and rain.
&&
.UPDATE...
Issued at 1056 PM EDT Mon Sep 24 2018
Southwest Lower Michigan will remain in a moist southerly flow
through the night. We are expecting scattered showers to continue
through the night as well as areas of drizzle and fog. Overall the
thunderstorm threat looks to be low, but cannot rule out a few
storms toward daybreak near I-94 especially. Instability is not
impressive (the RAP has 600 j/kg advecting in late). Some of the
convection allowing models have indications of a storm or two
though toward 12z.
&&
.DISCUSSION...(This evening through next Monday)
Issued at 325 PM EDT Mon Sep 24 2018
We are going into a very fall like weather pattern. This will mean
significant large swings in our daily temperatures and periods of
wet weather that at times will be rather windy.
Tonight we have a subtropical system passing off to our south and
east. Most of the significant rainfall with this system will be
east and southeast of Southwest Michigan. Still the dew points in
the 1000 mb to 850 layer coming into our area from the south are 3
to 5c higher than the current temperature. Clearly this will mean
extensive low clouds and some light sprinkle precipitation. This
also means temperatures will not be falling much overnight. Lows
will be in the lower 60s. A more significant rainfall event will
be passing just east of I-69 tonight.
Tomorrow we have a strong cold front heading this way. This should
push a surge of even warmer and more moist air our way for Tuesday
afternoon into Tuesday evening. There is a severe storm threat
tomorrow, mostly in the evening. This comes from the entrance
region of a 110 knot 300 mb jet core moving across central and
northern Lake Michigan early Wednesday morning. While there will
not be much surface based instability the deep layer shear from
the upper jet combined with the low level jet and the deep layered
moisture combined with system dynamics will result in the
potential for strong thunderstorms Tuesday evening. There could be
a severe storm threat during the daytime Tuesday expect for the
problem of to much low clouds to allow much surface heating.
Once that is done the cold front has a 10c in 12 hour drop in the
1000 mb, 925 mb and 850 mb temperatures. That will drive some
strong winds at the surface Wednesday morning and will also cause
temperatures to struggle to rise Wednesday. I could see many
placed in our northern and central CWA have highs in the 50s
Wednesday. A few lake enhanced light rain showers are possible
during the mid morning hours Wednesday but the moisture depth is
not deep enough for a significant shower event from that. We may
have to watch out for water spouts Wednesday.
Another strong northern stream comes through Thursday into Friday.
This could mean a few showers Thursday night into Friday but at
this point the deep moisture stays to far north to get much from
that.
Beyond that we have a front that seems to want to stall just south
of GRR late in the weekend so that will be an overrunning rain
event Sunday into Monday but there is a strong upper wave that
comes out early to midweek so we could see another significant
fall type storm early to midweek next week from that.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1130 PM EDT Mon Sep 24 2018
Mainly MVFR/IFR conditions will continue overnight through Tuesday
morning due to low cigs and scattered showers along with patchy
fog. Conditions will gradually improve to a mix of VFR/MVFR
Tuesday afternoon.
A few thunderstorms may develop Tuesday morning or afternoon but
potential in those is too low to warrant inclusion in the terminal
forecasts through the afternoon.
Thunderstorms are forecast at all the terminals Tuesday evening
when conditions will deteriorate to mainly MVFR with some brief
IFR possible as thunderstorms move through.
&&
.MARINE...
Issued at 134 PM EDT Mon Sep 24 2018
We will very likely need a small craft advisory Tuesday night
into Wednesday. It is touch early to issue those headlines yet so
we will wait to issue the headlines.
&&
.HYDROLOGY...
Issued at 956 AM EDT Sun Sep 23 2018
Rivers are running around to a little above normal for the time of
year. Levels are steady or slowly falling, and are well below flood
stage. Dry weather is expected into Monday. Under an inch of rain is
possible Monday into Tuesday, with no flooding expected.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...None.
&&
$$
UPDATE...Duke
SYNOPSIS...WDM
DISCUSSION...WDM
AVIATION...Laurens
HYDROLOGY...63
MARINE...WDM
Area Forecast Discussion
National Weather Service Houston/Galveston TX
934 PM CDT Mon Sep 24 2018
.UPDATE...
A line of showers currently extending from northern Colorado
County up into San Jacinto County should continue to diminish over
the next several hours. Some of these showers trained over
northern Colorado county for a few hours, with an estimated 2 to 3
inches of rain falling in some areas. 2.63 inches was observed by
a gauge 7 miles south of Weimar, which matches up pretty well with
the dual pol precip estimates from our radar. Luckily this rain
fell over a relatively dry area, and no issues have been reported
so far. Once these showers diminish, a fairly quiet night is
expected with some additional showers developing near the coast
overnight and spreading inland during the day tomorrow. 11
&&
.PREV DISCUSSION... /ISSUED 642 PM CDT Mon Sep 24 2018/
AVIATION [00Z TAF Issuance]...
The main concern the first 6 hours of the TAF will be showers
stretching from west of KCXO/KUTS back to the SW towards Columbus.
This is basically where the old frontal boundary has stalled and
yet to fully dissipate. Convection should be diurnally driven so
it should be dissipating over the next hour or two. VFR conditions
are expected going into the morning hours. TAFs do not reflect
this but still cannot rule out patchy fog depending upon cloud
cover clearing overnight. KCLL may get some MVFR ceilings as well.
Towards 09-15Z along the coast shower activity will become a
concern. This activity may grow upscale and push north as the
various WRF and HRRR runs depict. Confidence is low for VCTS/TSRA
at the moment so TAFS mention VCSH. This leaves room for better
model evaluation of timing of convection and possibly nailing down
details of deep convection that could affect terminals by the
afternoon.
Overpeck
PREV DISCUSSION /Issued 345 PM CDT Mon Sep 24 2018/...
DISCUSSION...
We`ll begin a transition back to a pre-frontal environment for the
first half of this week, then it is all eyes to the northwest for
the next cold front. Still some doubt as to how large an impact
we`ll see in our area due to this front, but the models have
stopped their trend towards a weaker setup and perhaps have even
been a bit more aggressive than previous runs. After that, we`ll
see onshore flow re-establish itself this weekend, though remnants
of the boundary may keep rain chances a little more elevated than
normal.
NEAR TERM [Through Tonight]...
Showers and storms have been pretty slow to get started this
afternoon, as the radar scope is virtually clear in our area.
However, there is a tiny bit of activity in the west, and the HRRR
(which seems to handling things decently well today) is insistent
that we`ll get more convective development in the late afternoon
and early evening. So...will hang onto chance and slight chance
PoPs in the west, gradually transitioning to nocturnal marine
showers late tonight.
For temperatures, have decided to take a bit more of a persistence
influence. Last night was a bit drier and cooler than forecast
(author`s opinion: blissfully) and so took a couple of degrees off
the model blend `first guess` field. Winds shifting to become
onshore overnight will likely keep temperatures from falling as
low as last night, but will at least undercut the guidance here.
SHORT TERM [Tuesday Through Thursday]...
Once back in a pre-frontal environment, look for Tuesday to follow
the late summer diurnal trend. Marine and coastal showers early in
the morning, gradually working their way inland through the
afternoon. Similarly, look for higher dewpoints and slightly
warmer temperatures on Tuesday. Similarly, we`ll see increased
rain chances, particularly closer to the coast. This sees pretty
good support in the HREF ensemble and TTU WRF - both systems seem
to have a pretty reasonable handle on tomorrow`s convective
evolution.
After a "typical late summer" Tuesday, we`ll focus on the approach
of an upper trough into the Great Plains, supporting a surface
cold front that will work its way into Texas. But...at the same
time, the digging trough will be battling the subtropical ridge,
also trying to assert its dominance over the area. The winner will
likely have important impacts on our sensible weather for the
midweek.
Modeled MSLP trends suggest a cold front that will make it to the
Gulf waters at some point on Wednesday night, though the timing
varies a few hours from model to model. But, curiously, the upper
environment in the GFS and Euro don`t really seem to support this
idea. Despite a decently strong upper trough, both models largely
have the ridge winning, and blunting that trough up to the
northeast around the Red River, leaving only a streamer of
vorticity to help push the front the rest of the way to the coast.
Similarly, their 850 mb cold pools get hung up around Waco, while
warmer low level air remains entrenched over Southeast Texas.
FWIW, the NAM is actually extremely aggressive with the ridge, and
blows a strong front to the coast with 20 knot winds behind it.
This...is probably a little too aggressive, given how little
support the idea has elsewhere. But, theoretically plausible.
Continue to take a bit of a compromise with the forecast, in which
a wind shift (perhaps aided by convective cold pools) gets shoved
to the coast, while drier and cooler air only manages to make the
slightest of progress past our northwestern border.
LONG TERM [Thursday Night Through Monday]...
Look for at least partially onshore flow to be back in place
around Friday morning, and there`s broad model consensus that
remnants of the frontal zone will remain in the area into the
weekend. Pair that with not much influx of drier air, and higher
rainfall chances should persist into the weekend - albeit not
quite as high as earlier in the week.
Though Friday may be a bit cooler thanks to the continuing
extensive cloud cover, expect a slow warmup in the following days
with continued southerly flow. Perhaps by Monday or Tuesday,
we`ll see temperatures back up into the upper 80s as upper ridging
builds back over the area. However, by this point, the GFS and
Euro are beginning to diverge very significantly, as a new upper
trough crashes into the Pacific Coast to widely varying degrees of
impact in the two models.
MARINE...
Weak onshore winds will ever slowly strengthen through early Tuesday
with the increase of shower and storm areal coverage that will
likely be moving in from the southwest. Higher moisture with weak
passing shortwave disturbances will pick up precipitation chances
ahead of an approaching central Texas (weak) cold front. The
greatest chance for maritime convection will be between Wednesday
and Friday. Winds and seas may quickly strengthen and become
agitated, respectively, around any thunderstorm. Questions reside on
whether this front will actually make it to the coast but higher
confidence resides with early Thursday variable winds becoming more
weak northeasterly through the day. Generally weak winds will veer
back onshore by the weekend. 31
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 72 91 73 85 67 / 10 20 20 70 60
Houston (IAH) 73 89 75 87 71 / 30 40 40 70 60
Galveston (GLS) 78 86 79 84 76 / 30 40 50 60 70
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
Discussion...11
Area Forecast Discussion
National Weather Service Wilmington NC
739 PM EDT Mon Sep 24 2018
.SYNOPSIS...
A weak cold front will linger over the area through Tuesday. Weak
low pressure moving toward the Carolinas from the Atlantic
tonight into Tuesday will turn north and weaken, remaining well
off of the Cape Fear coast. Rain chances will increase further
Thursday and Friday as a stronger cold front approaches the
coast. Drier and cooler high pressure will follow for next
weekend, bringing temperatures closer to normal for the early
Fall season.
&&
.NEAR TERM /THROUGH TUESDAY/...
As of 730 PM Monday...Scattered convective showers have been
squashed vertically by a subsidence inversion between 10-13kft.
Convective cloud tops have been observed by radar making it to
15-18kft before succumbing to dry air and relatively warm temps
aloft. The GFS and RUC point soundings show the inversion layer
dropping down toward 6kft over the next few hours, likely
squeezing the showers out of existence for most of the area.
Low pressure centered well offshore south of NOAA buoy 41002 has
been producing sustained convection north of the center for
many hours. NHC continues to watch it closely for signs of
tropical development. Showers ahead of the low may begin to
reach the Cape Fear and Grand Strand area very late tonight into
Tuesday. No significant changes have been made to winds or
forecast lows overnight.
Discussion from 300 PM follows...
Low clouds were eroding or lifting slowly, a little tougher to
erode inland as high pressure remains wedged in behind a cold
front. The front was aligned just off the coast this morning and
will remain in the vicinity as low pressure to the east moves
toward the Southeast coast tonight into Tues. The ridge aloft
was providing plenty of dry air and subsidence in the mid to
upper levels with a decent subsidence inversion apparent on
local soundings right around 6 to 7 k ft this morning but
eroding later this aftn. The moisture was getting stuck under
this inversion, but as it erodes through the afternoon, so
should the clouds. Although sunshine will increase in spots
through the afternoon, showers were continuing to move across
the waters near the coast and other spotty showers were
developing just inland. Some of the showers found off the coast
will push on shore, especially heading into the overnight hours
as winds become a bit more easterly.
The soundings show a brief opportunity this aftn with deep
enough layer of moisture and instability to put some iso
thunderstorms, but, otherwise, expect more in the way of shallow
convection through tonight into Tuesday as low pressure/disturbance
in the Atlantic waters advances toward the Carolina Coast. This
on shore push of moisture will be deep enough to generate
shwrs overnight into Tues. As the low approaches, the flow will
be more easterly into Tues morning, but will become more
northeasterly as the low turns to the north through Tues aftn.
Expect greater pops and qpf along the coast tonight into Tues.
Temps will remain above normal with most places inland between
65 to 70 for overnight lows and into the lower 70s closer to the
coast. The high temps on Tues should reach into the mid 80s.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 300 PM Monday...Period begins with weak surface wave/low
moving north-northeast over or just off the Southeast coast
under the western Atlantic mid-level ridge. The wave is quick to
move northeast Tue night, ending any diurnal convection, but
the mid- level ridge will hang on through the period. Surface
high to the northeast expands back into the region following the
exiting wave as slow moving cold front well northwest of the
region slowly approaches. Front will not be a player during the
forecast period and diurnal convection along the sea breeze and
Piedmont trough is expected Wed afternoon and evening.
Prefrontal trough may lead to some late day enhancement Wed, but
the loss of heating and persistent ridge should ultimately
cause activity to diminish during the overnight hours. Although
coverage will be negatively affected by subsidence under the
mid-level ridge, precipitable water values approaching 2 inches
warrants a chance pop. Marine convection may become more active
Wed night given a more slightly favorable environment.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 300 PM Monday...Mid level ridge hangs tough off the coast
early in the period, being attacked by the southwesterly jet
stream flow impinging from the NW. This setup drives a front
into the area Thursday and Friday, yielding the highest rain
chances for the entire forecast period. Fortunately rainfall
rates and amounts are expected to remain low enough for there to
be little to no effect on the ongoing river flooding.
Thereafter the boundary gets hard to discern on model progs as
the front washes out. The latter part of the period finds the
mid level ridge expanding greatly westward, becoming centered
over the Southeastern U.S. This keeps the center of the ridge to
our south and thus possibly it`s convection- suppressing
effects. This idea is supported by guidance, most of which still
crank out small precip amounts across the area into Monday.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
As of 18Z...Moist low-level east to northeast winds with dry air
aloft sets the stage for late night low stratus. Conditions
should begin to deteriorate around 08-09Z, particularly inland
where IFR conditions are likely to occur. Showers associated
with an offshore low pressure area will increase along the coast
after daybreak Tuesday with otherwise MVFR conditions expected
Tuesday morning after 14Z.
Extended Outlook...Increasing chances for showers and storms
Thursday through Saturday. Light morning fog possible each day.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
As of 730 PM Monday...NHC continue to watch low pressure well
offshore south of NOAA buoy 41002 for signs of tropical
development. Scattered showers occurring across the waters now
are not associated with this system, however outer bands of
showers circulating around the low could reach our coastal
waters late tonight into Tuesday. Seas are already building due
to SE swells emanating the northern half of the low`s
circulation. No significant changes are needed with this early
evening forecast update. Discussion from 300 PM follows...
Expect NE winds between high pressure nosing down into the
waters and low pressure moving closer to the local waters from
the Atlantic waters. Winds will shift more to the east on the
top side of the low as it nears the waters but as the low turns
northward on Tues, the winds will shift to a more NE direction
once again. The on shore push will lead to a rise in local seas
from 2 to 4 ft into the 3 to 5 ft range, but overall winds and
seas will remain just below SCEC thresholds.
SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 300 PM Monday...Weak surface wave in the vicinity Tue
night will back winds from northeast at the start of the period
to southwest by Wed morning. Southwest flow will continue
through the period with speeds increasing from 10 kt or less for
much of Wed to the high end of the 10 to 15 kt range later Wed
and Wed night as the gradient becomes more defined. Seas 3 to 4
ft to start the period drop to 2 to 3 ft by Wed morning. Seas
build slightly Wed night, increasing to 3 to 4 ft as the period
ends.
LONG TERM /THURSDAY THROUGH SATURDAY/...
As of 300 PM Monday...Rather quiet marine conditions expected
as a front stalls to the NW Thursday into Friday and then washes
out on Saturday. Wind will be SW and tend towards 10kt. In the
absence of any appreciable swell energy the area will be left
with a 2-3 ft wind wave.
&&
.TIDES/COASTAL FLOODING...
As of 300 PM Monday...Long fused coastal flood event on the
Cape Fear river ongoing. High tides will exceed warning level
(6.7ft MLLW) for the next several days as not only the flood
wave moves down river but astronomical tide builds with the
waxing moon. Not only will we see record-challenging high tide
levels into mid week, but low tides may not get below Advisory
levels. Please refer to any Coastal Flood Advisories or Coastal
Flood Warnings for further details.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...Coastal Flood Warning until 2 AM EDT Thursday for NCZ107.
MARINE...None.
&&
$$
SYNOPSIS...MBB
NEAR TERM...TRA/RGZ
SHORT TERM...III
LONG TERM...MBB
AVIATION...TRA
TIDES/COASTAL FLOODING...RGZ
Area Forecast Discussion
National Weather Service Wilmington OH
1059 PM EDT Mon Sep 24 2018
.SYNOPSIS...
Another round of showers, and perhaps a thunderstorm, is
expected overnight as moisture pushes northeast ahead of an
advancing warm front. This unsettled weather pattern will
persist with several rounds of showers and thunderstorms
offering the potential of heavy rain and flooding across
portions of the Ohio Valley until a strong cold front moves
through the area late Tuesday night into Wednesday morning.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
First round of showers is now exiting our eastern forecast area.
Region will be in a relatively lull through early morning behind
the exiting short wave. Thereafter, another low level jet and an
advancing warm front will allow showers, perhaps an embedded
thunderstorm, to develop. Latest HRRR has the greatest
convergence/focus across the Whitewater/Miami Valleys and west
central Ohio. This is where likely PoPs have been placed. It
should be noted that the models have been struggling with the
placement of this next round of rain, so this higher PoP event
could end up in other parts of the CWFA. We will continue to
monitor.
Not much of a diurnal drop in temperatures tonight with clouds
and winds staying up. Have lows remaining in the 60s.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
Mid level trof to translate east and amplify with developing
surface low ejecting northeast across the upper MS Vly Tuesday
and the Great Lakes Tuesday night. Wind profiles are favorable
for organized storms Tuesday afternoon into the evening but
uncertainty exists regarding instability.
In southwest flow ahead of this system warm front lifts north
across the area overnight into early Tuesday. In the warm
sector, some breaks and advection of dewpoints into the upper
60s should yield moderate moderate instability of 1000-1500
j/kg during the late afternoon over ILN/s western counties. Have
continued mention of potential for severe weather in the HWO
product with damaging winds being the main threat.
Heavy rain threat to persist with pw/s remaining close to 2
inches and an enhanced coverage of convection later Tuesday
afternoon with an emphasis Tuesday night ahead of surface cold
front. Have flash flood watch across the south and southeast
thru Tuesday night with two day storm totals of 1 to 3 inches
and locally up to 4 inches possible.
Expect warmer temperatures with highs from the mid 70s
northeast to the upper 70s southwest. Mild lows Tuesday night
from the lower 60s northwest to the upper 60s southeast.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
A cold front will be moving through during the daytime hours on
Wednesday. As this front moves through there will be the potential
for a few isolated damaging wind gusts. Outside of thunderstorm
activity wind gusts around 20 to 25 mph will be possible.
Precipitation will then taper off through day the day. Cooler
conditions will be present Wednesday night with lows dropping into
the 40s and 50s.
High pressure will allow for dry conditions through Friday night. On
Saturday a cold front moves through the region. There is little in
the way of moisture with this system and therefore only have a
slight chance of rain showers in the forecast for Saturday. On
Sunday there will be a gradient in temperatures as a warm front is
situated near the area. This front will lift northward Sunday
night. Moving into Monday, thunderstorms are expected to develop
across the area during the day.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
Widespread showers in association with an embedded disturbance
within a moist southwest flow aloft will continue to shift east
through early morning. MVFR/IFR conditions will persist.
For the overnight period, a warm front is expected to push
northeast into the region. This will be associated with another
low level jet which will result in another round of showers and
perhaps isolated thunderstorms. This will keep conditions poor
with MVFR/IFR ceilings and visibilities fluctuating between
MVFR and IFR.
On Tuesday, timing and coverage of precipitation becomes a
little more muddled. Warm front and low level jet should be
exiting to the northeast, which may provide a lull in
precipitation from mid morning into early afternoon. Then, with
some diurnal heating/increasing instability and perhaps
convergent low level flow, scattered showers/thunderstorms will
develop later in the afternoon, becoming likely Tuesday night
ahead of a cold front. Overall ceilings will try to lift between
2500 and 4000 feet late in the day, but with the threat for
showers/thunderstorms, aviators need to be aware of continued
lower conditions (MVFR/IFR) in the showers/storms.
Southeast winds around 10 kts will veer to the south overnight
and then south-southwest and gust up to 20 kts on Tuesday.
OUTLOOK...Thunderstorms with MVFR ceilings and MVFR/IFR
visibilities expected to continue Tuesday night into Wednesday.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...Flash Flood Watch through late Tuesday night for OHZ073-074-
077>082-088.
KY...Flash Flood Watch through late Tuesday night for KYZ089>100.
IN...Flash Flood Watch through late Tuesday night for INZ073>075-
080.
&&
$$
SYNOPSIS...Hickman/AR
NEAR TERM...Hickman/AR
SHORT TERM...AR
LONG TERM...Novak
AVIATION...Hickman
Area Forecast Discussion
National Weather Service Indianapolis IN
1154 PM EDT Mon Sep 24 2018
.UPDATE...
The AVIATION Section has been updated below.
&&
.SYNOPSIS...
Issued at 234 PM EDT Mon Sep 24 2018
A frontal system is expected to affect the area into Wednesday
morning. In the wake of this front, high pressure will move into the
area for the latter parts of the week.
&&
.NEAR TERM /Overnight/...
Issued at 930 PM EDT Mon Sep 24 2018
Broad Isentropic lift continues across the forecast area as a
poorly organized warm front lingers in the area. Low ceilings with
some patchy drizzle remain in place mainly east of a Kokomo to
Bloomington line. HRRR continues to suggest shower development
over southern Illinois and western Kentucky to push into Central
Indiana overnight. Radar mosaics failing to show much of this
development yet and confidence is waning. Furthermore with low
clouds in place and minimal instability...thunderstorms appear to
be a stretch. Given the lift a rumble of thunder cannot be ruled
out...but widespread storms appear unlikely. Downplayed that in
the forecast. Used steady state temperatures given the expected
cloud cover and drizzle/rain chances.
&&
.SHORT TERM /Tuesday through Thursday/...
Issued at 234 PM EDT Mon Sep 24 2018
Will keep PoPs rather high through the midday hours of Tuesday, as
model data suggest decent lift will continue in association with the
850mb jet. Precipitation threat may tend to diminish during the
afternoon hours, as the core of the 850mb jet moves off to the east.
At this time, it appears cold front will pass through the area late
Tuesday night into Wednesday morning. Will keep rather high PoPs
going Tuesday night ahead of cold front, with a decent low level jet
ahead of the front. Will keep some chance PoPs going through
Wednesday morning to cover any lingering activity near the exiting
front.
Deep layer shear becomes favorable for strong organized convection
by Tuesday afternoon and night, although lapse rates continue to
look poor.
Will go with a dry forecast for Wednesday night and Thursday as
surface high pressure moves into the area.
Based on low level thickness progs, the GFs MOS temperature guidance
over the next couple of days looks reasonable, so only minor
adjustments planned.
&&
.LONG TERM /Thursday night through Monday/...
Issued at 313 PM EDT Mon Sep 24 2018
Dry weather with near normal temperatures (highs in the low to mid
70s, lows in the low 50s) to start the long term with high pressure
over the area. A frontal system will start to move through the Great
Lakes for the weekend and this will bring small rain chances to
northern parts of the area starting by Saturday afternoon and
lasting through the night. At this time models are showing the front
possibly washing out or lifting north Sunday which is leaving the
forecast dry for Sunday. Monday chances sneak back in as the front
could make a bit more progress into the area, but confidence is low
with low agreement from models and ensembles. Heights building
Monday could bring temperatures above normal.
&&
.AVIATION /Discussion for the 250600Z Tafs/...
Issued at 1154 PM EDT Mon Sep 24 2018
IFR conditions are expected at the Taf sites for much of the next
6 to 12 hours.
Poorly defined warm front and associated isentropic lift will be
in place across Indiana overnight. Radar shows light rain showers
developing upstream of the taf sites across east central Illinois.
Coverage is scattered at best. HRRR continues to suggest limited development
of showers overnight. Confidence for thunder is low given the
moist lapse rates and minimal instability. Forecast soundings keep
plenty of lower level moisture in place overnight. Thus have
continued with IFR Cigs.
Some improvement to MVFR or better might be possible after
sunrise on Tuesday. More showers and storms will be possible along
with IFR conditions on Tuesday afternoon and evening as a cold
front approaches from the northwest. Any storm that does strike a
taf site will produce brief MVFR or worse conditions.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JAS
NEAR TERM...Puma
SHORT TERM...JAS
LONG TERM....CP
AVIATION...JP
Area Forecast Discussion
National Weather Service Marquette MI
645 PM EDT Mon Sep 24 2018
.SHORT TERM...(This evening through Tuesday)
Issued at 409 PM EDT MON SEP 24 2018
WV imagery and RAP analysis indicated a mid/upper level trough from
Saskatchewan into the central Rockies resulting in sw flow from the
plains into the upper MS valley and northern Great Lakes. At the
surface, a cold front extended into western MN from low pressure
over northwest Ontario( near CYPL). Strong 800-600mb associated with
the front supported showers from north central into wrn MN. WAA with
brisk southerly winds ahead of the front along with sunshine has
pushed temps into the mid to upper 60s.
Tonight, expect the showers to gradually advance into the west late
this evening. However, the showers will diminish overnight before
they move through central Upper Michigan as the fgen weakens and
lifts north of Lake Superior. Forecast MUCAPE values look marginal
to support any tsra. Some light rain or drizzle will also be
possible east where WAA isentropic lift and low level moisture
increases late this evening and overnight.
Tuesday, Models suggest that the shortwave moving through the
Rockies into the plains tonight will support the development of a
sfc low/wave that will advance into the western Great Lakes by
the afternoon and evening. Fgen to the nw of the path will again
be strong enough to support widespread rain through most of Upper
Michigan. However, the NAM and ECMWF, in line with many GEFS
members have trended slightly weaker with the system and keep the
heavier rain farther south compared to the GFS. Expect overrall
rainfall amounts generally in the 0.25-0.75 inch with the greatest
amounts over the central and east.
.LONG TERM...(Tuesday night through Monday)
Issued at 348 PM EDT MON SEP 24 2018
Fairly typically fall weather in the long term with not significantly
impactful events expected.
A shortwave will push through Tue night as a compact surface low
moves SE of the CWA. Fgen on the NW side of the low, along with
forcing from the shortwave, will lead to a decent area of rain over
the SE 2/3 or so of Upper MI. Have 0.25-0.5 inches of rain in that
area between 00Z and 06Z Wed.
Scattered to isolated light lake enhanced rain showers near Lake
Superior will gradually taper off from late Tue night through Wed
morning.
Next chance of rain moves in Thu as a shortwave and surface trough
move through. Behind that could see some lake enhanced rain showers
through Fri , but coverage looks limited.
Could see another round of rain for parts of the area Fri night, but
that is quite uncertain at this point.
High pressure looks to move over around Sat night, bringing a dry
period. Potential for a decent system to move through Sun night into
Mon, but there is a lot of model disagreement so can`t get into any
details at this point.
Depending on precip/cloud coverage, could see some decent frost
potential Fri night and Sat night.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 645 PM EDT MON SEP 24 2018
VFR conditions will continue through the late evening and then rain
and MVFR conditions will move in from west to east. Conditions will
drop to MVFR for a period and will likely fall to IFR/LIFR at KIWD
and KCMX and eventually at KSAW early Tuesday. Conditions will
improve Tue afternoon to MVFR at all sites.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 409 PM EDT MON SEP 24 2018
With a cold front moving through tonight/Tue morning, winds will
shift to the nw at 15-25kt for Tue, strongest over the e half of the
lake. May be able to slip in a day with winds mostly under 20kt on
Wed before the next low pres system moving e toward northern Ontario
brings stronger sw winds of 20-30kt again on Thu that will veer to
the nw Thursday night.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JLB
LONG TERM...Titus
AVIATION...07
MARINE...JLB
Area Forecast Discussion
National Weather Service New York NY
1103 PM EDT Mon Sep 24 2018
.SYNOPSIS...
High pressure will retreat to the northeast overnight as a warm
front approaches from the southwest. The warm front will slowly
move through the region Tuesday into Tuesday evening. A cold
front will move across the area Wednesday. High pressure will
build to the north through the end of the week. Another weak low
will affect the area Thursday. High pressure will build in
Friday and remain for much of the weekend and into the beginning
of the week.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A northern stream 700-500 hPa shortwave moves into PA/Upstate
NY/Western Great Lakes overnight, as the deep layered ridge axis
lifts to the northeast. Meanwhile, a surface-850 hPa warm front
approaches from the SW.
A 35-45 kt 950 hPa jet builds over Long Island overnight. This
will help to rapidly expand the rain shield to the NE - this
idea is supported by the latest HRRR/HiResW-NMM/CMC/NAM/GFS/ECMWF.
It should be noted that the latest RAP and HiResW-ARW model
are slightly faster - closer to the 18Z CMC-Reg while the 00Z NAM
and HiResW-NMM are slightly slower than their previous runs.
Continue with idea of rain overspreading the region overnight,
and being locally heavy at times for all but far east portions
of the CWA. The driving forcing behind the locally heavy
rainfall will be the arrival of the 950 hPa jet and the
building into the area of a low level theta-e ridge overnight.
The region will also be in the right rear quadrant of a fairly
weak (55-60kt) 300 hPa jet streak.
There is a high rip current risk for the Atlantic beaches
overnight.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
Minor adjustment to the forecast Tuesday morning, was to change
the precipitation to rain, as the surface-850 hPa warm front
remain to the SW and isentropic lift remains very strong during
this time frame. Also appears that most instability, even aloft
holds off until afternoon, with showalter indices generally
above 2 through the morning.
The warm front lifts slowly through the region from the
southwest through the day Tuesday and should be north of eastern
Connecticut during the evening hours. An accompanying shortwave
will add to the frontal lift, and precipitable water values will
increase to around 2 inches by Tuesday morning. Instability and
CAPE will be increasing with the front and areas of heavy
rainfall and thunderstorms will be possible along the front. A
low level jet of 40-50KT will also enhance the precipitation,
and with the heavier showers some of these high winds may be
brought down to the surface. Again, timing of the frontal
passage was similar, slightly slower with the GFS. Leaned
toward the GFS for probabilities, which taper off with the
passage of the warm front, with the precipitation possibly
ending as the area becomes warm sectored. Also, leaned toward
the MAV/GFS guidance for temperatures and temperature trends for
Tuesday and Tuesday night.
There is a high rip current risk for the Atlantic beaches on
Tuesday.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
A strong cold front will move across the area late on
Wednesday. There might be some breaks in the clouds Wednesday,
and higher humidity levels that could result in showers and
thunderstorms. SPC has most of the area under slight risk of
severe weather on Wednesday. The greatest potential for any
severe weather will be late Wednesday and Wednesday night as the
cold front moves across the area.
High pressure builds north of the region, meanwhile the cold
front stalls south of the area. Another weak low will affect the
area Thursday bringing another chance chance of precipitation
to the region on thursday night and Friday.
A stronger area of high pressure builds into the area this
weekend, with dry weekend expected, then moves offshore Monday.
Temperatures will be above normal on Wednesday then fall to
near normal for this time of year on Thursday and remain near
normal for the remainder of the long term period.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
A warm front slowly approaches from the southwest tonight
before moving through the area by Tue evening.
Cigs will lower thru 6z to mvfr across the entire area, with
2500 ft clouds coming in from the ne. At the same time, rain
will overspread the area from the sw, producing ifr by Tue
mrng. This ifr is likely to last most of the day, with potential
breaks to mvfr or better behind the warm front. There is a high
amount of uncertainty however as to how much improvement will
actually occur. Tstms possible aft 16z, however the exact timing
and coverage is too uncertain to include in the tafs attm.
Mainly ifr is expected to develop again Tue ngt.
E winds tngt veer to the se Tue, then become sly after the warm
fropa. The strongest speeds will be tngt and ahead of the front
on Tue, then speeds diminish to mainly 10kt or less thru the
remainder of the taf period.
Gusts may only be ocnl at times. Where gusts cut off, marginal
llws can be expected with winds at 2000 ft up to 45kt.
.OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
.Tuesday night...Periods of rain/showers with MVFR. IFR or
lower possible. E wind gusts of 25-30 kt, becoming SE.
.Tuesday night-Wednesday...Showers and isolated tstms possible
with MVFR or lower at times. Southerly winds.
.Thursday-Saturday...VFR.
&&
.MARINE...
A strong pressure gradient will remain across the waters into
Tuesday, that then relaxes from W to E Tuesday afternoon as the
surface warm front lifts to the NE. As a result, have Small
Craft Advisories up on all waters through 18Z, and on all but
New York harbor and Western Long Island Sound through 22Z
Tuesday. As a low level jet moves through Tuesday morning,
occasional gusts, especially on the ocean waters, may be near
gale force for a couple of hours. Winds diminish Tuesday
afternoon and are expected to fall below SCA levels on all the
waters by Tuesday evening. A SCA will remain on the ocean waters
Tuesday night as seas remain elevated.
Ocean waters will remain above SCA levels on Wednesday. Have
extended the SCA advisory through Wednesday night. Conditions
across the ocean waters are expected to remain above 5 feet
through Thursday. Seas slowly fall below 5 ft Thursday night and
friday as the pressure gradient relaxes. Seas are expected to
remain below SCA levels through the weekend.
&&
.HYDROLOGY...
Total rainfall of 1 1/2 to 2 1/4 inches, with locally higher
amounts, is possible from late tonight through Wednesday night.
The heaviest rainfall is expected from late tonight into
Tuesday morning when around 3/4 to 1 1/4 inches on average, with
locally higher amounts, will be possible. Moderate to locally
heavy rainfall will be possible Wednesday and Wednesday evening.
At this time there will be the potential for localized
flooding, mainly of urban and poor drainage areas, from late
tonight into Tuesday evening. Localized flooding is possible
Wednesday.
&&
.TIDES/COASTAL FLOODING...
Approached or went just over minor coastal flood benchmarks
across the back shore bays of S NYC/Nassau. With forecasts
slightly higher for the high tides on Tuesday morning at these
locations, have gone ahead and issued a coastal flood statement
for the Tuesday morning high tide. The overnight shift, will
continue to assess, and might need to issue a short fused
coastal flood advisory if it appears that things are trending
towards what is currently the higher end of the guidance
spread.
&&
.EQUIPMENT...
NYC NOAA Weather Radio Station KWO-35 (162.55 MHz) remains off
the air for an extended period of time.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Rip Current Risk through Tuesday evening for NYZ075-080-
081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 2 PM EDT Tuesday for ANZ335-338.
Small Craft Advisory until 6 PM EDT Tuesday for ANZ330-340-345.
Small Craft Advisory until 6 PM EDT Wednesday for ANZ350-353-
355.
&&
$$
SYNOPSIS...Maloit/19/Fig
NEAR TERM...Maloit/19
SHORT TERM...Maloit/19
LONG TERM...Fig
AVIATION...JMC/MD
MARINE...Maloit/19/Fig
HYDROLOGY...Maloit/19/Fig
TIDES/COASTAL FLOODING...
EQUIPMENT...
Area Forecast Discussion
National Weather Service Paducah KY
938 PM CDT Mon Sep 24 2018
.UPDATE...
Issued at 938 PM CDT Mon Sep 24 2018
A little bit of a challenge for the first period PoPs and weather
overnight.
Significiantly backed off on areal coverage over the western half
of the WFO PAH forecast area (mainly southeast Missouri and
southern Illinois) during the evening, ramping up PoPs closer to
the 09z-12z (4-7 am CDT) time frame. Also, gradually introduced
isolated thunderstorms with PoPs from south to north between 03z
and 09z (10 pm CDT to 4 am CDT).
For eastern sections of the WFO PAH forecast area, dropped PoPs
altogether as insufficient moisture advection, lift, instability
will exist in that area for most of the night.
The surface/low level theta-e axis continues to extend from
northeast Arkansas, northward to the southeast Missouri foothills
to near Perry County Illinois, then northeast to Mount Vernon
Illinois and eastward. The western end of this theta-e axis
mirrors the subtle surface trough between the western Arkansas and
northeast Missouri minor surface lows and the attendant warm front
along and north of the Interstate 64 corridor in southern
Illinois.
As forcing associated with another mid-upper rough axis moving
from southeast Kansas moves slowly east-northeast toward southeast
Missouri and southwest Illinois overnight, the attendant
instability should initiate new and more robust convection. At
this time, it looks like the best chances for increased coverage
will be around or after 09z over southwest Illinois and possibly
southward into southeast Missouri. The ESRL HRRR, GFS, and NAM-
WRF (ARW) version, seem to be consistent with this scenario,
although the coverage is much greater than anticipated.
Made some adjustments to wind, temperature, and dewpoints to
reflect increased warm air advection overnight.
UPDATE Issued at 627 PM CDT Mon Sep 24 2018
Plans are to let the Flash Flood Watch expire as scheduled at 7 pm
CDT for the west Kentucky Pennyrile region. Any activity within
the watch area has been marginal at best and the potential for
further flooding overnight will be nill.
Current convection over southeast Missouri and into extreme
western Kentucky and southwest Illinois is occurring within a
narrow surface/low level theta-e axis, just west of the large
plume of two inch precipitable water. A minor low near the St.
Louis area on the LAPS data is a reflection of a minor mid-level
wave with an axis oriented north to south into southeast Missouri.
This narrow axis of instability will generally translate the
convection northeast, where it will impinge on a marginal surface
warm front arcing from near St. Louis to north of Lawrenceville,
IL, and Bowling Green, KY. This may cause an uptick in convection
later this evening along and north of the I-64 corridor in IL/IN.
There is still a minor wave embedded in the southwest to northeast
flow over Arkansas at this time. There may be enough instability
to generate marginal showers and a few thunderstorms on the
western end of the surface plume of moisture associated with the
low level theta-e axis. The last couple of hours of HRRR model
runs hint at minor activity through the evening, then another
uptick around 10-12z (5 am to 7 am CDT) on Tuesday. At this point,
do not see any flooding and/or severe weather concerns for the
overnight hours.
&&
.SHORT TERM...(Tonight through Wednesday night)
Issued at 212 PM CDT Mon Sep 24 2018
Ongoing pcpn episode continues, as rain overruns warm front and
high theta/moisture laden air precipitates efficiently with PW`s
still running 95th percentile plus. However, a break is on the
way, as all Cams show pcpn winding down this evening. Will
therefore let FFA expire at natural expiration (00Z Tue), unless
collab efforts suggest otherwise.
Looking ahead, we warm sector tmrw, then height falls with
increasing upper difluence will introduce that slgt risk svr into
the northern most parts FA late in day into the evening hours.
About half the Cams suggest some late pm/early evening
development, but that may well depend upon if we can break the
cloud cover and destabilize, which is an iffy proposition at best.
It may well be that the majority of our pcpn remains elevated warm
sector, unless/until the cold front comes into play, which will be
tmrw night-Wed. Should see the pcpn ending west to east as the
front makes passage late Tue night into Wed.
It will stay warm/muggy in warm sector, with 70s/60s and some 80s
if breaks occur. Then post frontal, we should cool to 50s Wed
night. Dew points stay in the 70s til after fropa, when they
likewise bring 50s, maybe even upper 40s north.
.LONG TERM...(Thursday through Monday)
Issued at 246 PM CDT Mon Sep 24 2018
Models show surface high pressure moving from the central Plains
into the Ohio valley for the end of the work week. We will continue
to see dry conditions Thursday through Saturday with a gradual
increase in temperatures and dew points. Skies should be clear to
partly cloudy through the period, though a weak upper level wave may
give us a little more cloud cover Thursday morning. Highs will go
from the lower 70s Thursday to the upper 70s to around 80 degrees
Saturday. Lows will be in the middle to upper 50s, which is
seasonal.
A slow moving frontal boundary will begin to affect our region on
Sunday. We should see a few more clouds by Sunday, and there will
be a small chance of showers and thunderstorms mainly in southeast
Missouri. Dry conditions are expected Sunday night, then a slight
chance of showers and storms can be expected across the entire area
Monday with the boundary in our region and daytime heating. Highs
Sunday and Monday will be near to a little above seasonal in the
upper 70s to lower 80s, with dew points climbing back up into the
upper 60s to around 70 degrees.
&&
.AVIATION...
Issued at 627 PM CDT Mon Sep 24 2018
A significant improvement seen in cigs this evening as drier air
works north across the area. Still isolated convection near the MS
River. Have improved our Cig forecast through the 1st 1/2 of
tonight given current satellite trends. Later tonight the models
continue to indicate lowering cigs lasting into Tuesday morning,
followed by some improvement in the afternoon. Mainly MVFR cigs
though local IFR possible especially southern IL into southeast
MO. Vsbys not expected to be too much of a problem given a
sustained south breeze overnight, that will become SSW around 10
kts or so Tuesday. Scattered showers and storms possible Tuesday.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...Smith
LONG TERM...RST
Area Forecast Discussion
National Weather Service Shreveport LA
955 PM CDT Mon Sep 24 2018
.SHORT TERM...
Lovely evening with fair skies and most sites anywhere from 1 to
3 degrees of a T/Td spread and #dew on car tops already. We have
added patchy fog mention in after midnight with expectations for
some dense fog in a few spots that are hard to nail down now
depending on sky cover.
Meanwhile, the day`s rains have edged eastward and the HRRR is
looking on top of that, but also with some new showers along parts
of the I-30 corridor in the wee hours. As skies continue to clear
for now we will bottom out early after midnight while walking a
tight rope down to saturation. Then once a fog gets going, it may
get worse or even lift off the deck right around daybreak just as
the morning low clouds are developing. /24/
&&
.PREV DISCUSSION... /issued 709 PM CDT Mon Sep 24 2018/
AVIATION...
For the ArkLaTex, VFR cigs will continue to lift into middeck early
this evening with some fair skies allowing for BR/FG to develop
after 06Z and continue to slowly lift from IFR to MVFR 12-16Z. SFC
winds are and will continue vrb03KT with S/SW flow 5-10KT for
Tuesday. Our climb winds are SW 10-20KT and veer to W/NW for
flight level 20-30KT. The recent fropa was short lived and we`ll
see a warming trend while keeping on the drier side tomorrow with
more convection widespread during midweek. /24/
PREV DISCUSSION... /issued 320 PM CDT Mon Sep 24 2018/
SHORT TERM.../Tonight through Tuesday Night/
Southerly flow to increase areawide maintaining a moisture
rich air column through much of the short-term period. An upper-
level trough across east Texas will linger through Tuesday night
allowing for periods of convection with the highest chances during
the hours of max diurnal heating with elevated convection
lingering through the evening and overnight hours. Most of this
convection will occur across our eastern zones which include north
Louisiana and southern Arkansas.
South winds will persist throughout the short-term period ranging
from 5 to 10 mph during the daytime hours and 5 mph or less
overnight.
Otherwise, overnight low temperatures tonight and Tuesday night
to range from the mid 60s across the I-30 corridor to the lower
70s elsewhere while highs on Tuesday will climb into the upper
80s. /05/
LONG TERM.../Wednesday through Monday/
A rather active weather pattern will remain in place for most of the
long-term forecast period as a longwave trough slowly moves east
across the CONUS. On Wednesday, the main vort max associated with
the trough will move across the Upper Mississippi Valley and into
the Great Lakes. This will help to push a cold front across the
forecast area. Additional vertical ascent from a weak embedded
shortwave trough should aid in the development of widespread showers
and thunderstorms on Wednesday. Southwesterly flow aloft will
provide abundant deep layer moisture. Model guidance suggests
precipitable water values will be well over two inches, which should
promote efficient rainfall producers. The highest rainfall totals
should be along and south of Interstate 20 over areas that did not
receive heavy rains during the last event. Therefore, widespread
flooding is not currently anticipated. However, any training of
storms could lead to locally heavy rainfall and isolated flooding.
The front should become stationary near the Gulf coast on Thursday.
However, the main longwave trough axis will be passing overhead,
which should lead to more rain across the southern half of the
forecast area. As the old front returns as a warm front on Friday,
rain chances will once again spread northward. Rain chances become
more uncertain during the weekend. An upper level ridge will begin
to develop over the Southeast CONUS, and the ridge will either
slowly expand westward or the center will retrograde over our area.
Medium range models suggest the ridge will not be particularly
strong, so it will likely not be enough to completely suppress
convective development during the weekend and into the beginning of
next week. However, most of the showers and storms should become
largely diurnally-driven.
The cold front and widespread rain and cloud cover should keep
daytime temperatures below normal Wednesday and Thursday. After the
warm front moves north across the region on Friday, a gradual
warming trend is expected through the remainder of the extended
forecast period. Even though temperatures will generally remain
below 90 degrees F through Monday, the rain and high moisture levels
will result in very humid conditions.
CN
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 70 89 72 83 / 10 30 30 60
MLU 72 90 72 85 / 10 40 40 60
DEQ 66 87 67 77 / 20 20 30 30
TXK 69 87 69 78 / 20 20 30 40
ELD 69 88 70 81 / 10 30 30 50
TYR 71 88 71 81 / 10 20 20 50
GGG 70 88 71 82 / 10 20 30 60
LFK 71 90 73 86 / 10 30 30 70
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
24/05/09