Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/07/23
Area Forecast Discussion
National Weather Service La Crosse WI
1101 PM CDT Wed Sep 6 2023
.DISCUSSION...(This evening through Wednesday)
Issued at 252 PM CDT Wed Sep 6 2023
Key Messages:
- Showers Ending This Evening. Little additional rainfall.
- Valley fog expected Thursday Night.
- Rain chances return Saturday night and continues into early
Next Week.
For tonight, the trough of low pressure responsible for the
instability showers and storms today will move east of the area.
With the instability waning tonight and the best moisture
transport moving off to the east, these showers will likely end
by 8 PM tonight. Additional rainfall for this evening will range
from a trace to a few hundredths of an inch.
On Thursday, high pressure will be building across the region.
With some cyclonic flow aloft and 850 mb temperatures falling to
around 10C, we will likely continue to see plenty of instability
clouds. High temperatures will range from the lower 60s to
lower 70s.
On Thursday night, skies will gradually clear across the area.
With winds less than 10 knots up to 850 mb and temperatures and
temperatures falling into the 40s, we will likely see the
development of valley fog in the Mississippi tributaries and
Wisconsin, and over the marshes and cranberry bogs in central
Wisconsin. Due to dew points drying and drought, there is still
some uncertainty on how widespread the valley fog will be in the
main channel of the Mississippi River valley.
From Saturday night into early next week, a front will move slowly
southeast through the region. The GEFS and ECMWF ECE are still
showing quite bit of uncertainty on location and rainfall amounts.
At this time, rainfall amounts look to be on the light side.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1055 PM CDT Wed Sep 6 2023
MVFR ceilings are forecast to persist overnight and into Thursday
morning at both KRST/KLSE per the RAP low level moisture relative
humidity progs. The KMPX 00Z sounding had shallow moisture and
satellite imagery showed some breaks. The RAP/NAM forecast
soundings show the inversion trapping the low level moisture
overnight and into Thursday morning with improvement to VFR
ceilings during the afternoon. Northwest to northeast winds 6 to
12 kts during the period.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
DISCUSSION...Boyne
AVIATION...Zapotocny
Area Forecast Discussion
National Weather Service Dodge City KS
603 PM CDT Wed Sep 6 2023
...Updated Aviation Discussion...
.SHORT TERM...(This evening through Thursday night)
Issued at 1248 PM CDT Wed Sep 6 2023
Latest visible satellite imagery and surface observations
indicate smoke from wildfires in Canada has advected all the way
southward into the central plains, which has impacted visibilities
and temperatures across our area as many locations are multiple
degrees cooler than progged. HRRR near-surface smoke fields depict
this smoke mixing out through the afternoon and early evening,
however likely not in time for southwest KS to reach the current
MaxT grid of mid/upper 80s to near 90, so expect a slightly cooler
afternoon than previously forecast. Overnight, quiet conditions
will continue as lows drop into the upper 50s/low 60s.
Daytime Thursday, 500-mb heights will inch upward as upper level
ridging builds over the southern plains/Desert Southwest. Strong
subsidence under this feature will induce 850-mb temperatures
warming by roughly 5-7 degrees Celsius, which will translate to a
spike in afternoon temperatures across southwest KS with highs in
the upper 90s/low 100s.
.LONG TERM...(Friday through Wednesday)
Issued at 134 PM CDT Wed Sep 6 2023
Key Message: Slow cooling trend begins Friday and continues
through the end of the period. Precipitation chances becoming
increasingly likely during the latter half of the period,
especially Sunday and Monday.
No change to the long term forecast compared to this time
yesterday as medium range ensembles continue to suggest the upper
level ridge over the southern plains/Desert Southwest at the
beginning of the period will slowly retrograde through Saturday,
and then be shunted further south off the southwestern CA coast
Sunday through Wednesday. This gradual pattern change will result
in a slow cooling trend throughout the long term, as afternoon
highs decrease from the low/mid 90s on Friday, to the low/mid 80s
on Sunday, and finally to the low/mid 70s by Tuesday/Wednesday.
In addition to the cooler temperatures, ensembles have persisted
in their forecast of widespread precipitation across southwest KS,
especially in the Sunday evening-Sunday night time frame, likely
in the form of a loosely organized mesoscale convective system
rolling southeast out of eastern CO. All 50 EPS members and all
but one of the 30 GEFS members forecast at least some QPF across
the entirety of the DDC CWA. Furthermore, NBM pops have increased
considerably in the 00-06Z Monday time frame, as now all areas are
within the likely category (55-74%), with some within the
definite category (75-100%). So in short, confidence is very high
in widespread rainfall during this period. Only remaining
question surrounds how much severe potential this activity will
possess. Ensembles suggest 500-mb flow will be on the order of
30-35 kts atop surface southeasterlies, which would foster
sufficient deep-layer shear for organized convection. However,
given the fact it appears this will be an overnight event,
instability will be a significant mitigating factor. Isolated
severe wind gusts would not be a surprise, but widespread severe
is not currently anticipated.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 600 PM CDT Wed Sep 6 2023
The visibility from earlier today across across southwest Kansas
was reduced to 2-4sm due to the smoke from the Canadian fires.
HRRR smoke graphics did a decent job with this smoke spreading
into southwest Kansas last night and as of 21z Wednesday it has
this smoke sliding east into central and eastern Kansas early
tonight. Visibilities will be improving to greater than 6sm
between 01z and 03z Thursday. A trough of low pressure over
eastern Colorado overnight will keep the winds tonight southeast
at 10knots or less. BUFR soundings indicating VFR conditions.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 61 101 62 95 / 10 10 10 0
GCK 61 98 60 92 / 10 10 0 0
EHA 62 99 60 93 / 10 10 0 0
LBL 59 102 60 95 / 10 10 10 0
HYS 57 100 60 92 / 10 10 10 0
P28 62 102 66 96 / 10 10 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Springer
LONG TERM...Springer
AVIATION...Burgert
Area Forecast Discussion
National Weather Service Grand Forks ND
632 PM CDT Wed Sep 6 2023
.UPDATE...
Issued at 631 PM CDT Wed Sep 6 2023
Some guidance is indicating a fog potential around Bemidji and
Park Rapids around sunrise Thursday morning. That area has yet to
clear, so will continue to monitor that potential this evening.
Otherwise, no other changes are needed to the forecast at this
point.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 302 PM CDT Wed Sep 6 2023
Key Messages:
-Smoke continues to move across the area, with some near surface
smoke creating visibility reductions at times.
-Cooler temperatures today and tomorrow, as highs reach the 60s to
lower 70s.
-A slight chance (10%) for a shower tomorrow afternoon and evening
along the international border as a system shifts across central
Canada
Discussion:
The near term looks to be quiet, but smokey across eastern ND and NW
MN. Continued wildfire smoke will impact the region the rest of
today and into tomorrow. RAP and HRRR smoke analysis has highest
concentrations of near surface smoke shifting into western ND
tomorrow afternoon and evening. However, that is not the case today
as we will continue to see near surface smoke the rest of the
afternoon and into the overnight hours. Impacts to sensitive groups
and visibilities will be possible. Smoke aloft will continue to bring
hazy conditions through the rest of the near term and potentially
into the long term at times. This is all thanks to the flow aloft
being from the NW. Canadian wild fires are currently located in
concentrations over Alberta and British Columbia. Flow aloft is
shifting that smoke into our area.
Otherwise; cooler, and more seasonal temperatures are expected today
and tomorrow. Highs will be in the upper 60s to lower 70s under
filtered sunshine. Some broken cumulus are possible at times this
afternoon as the upper level trough that brought precip to our area
shifts eastward. CAA from Canada is helping develop some of the
cumulus, but once daytime heating is lost we loose the cloud deck. A
passing system in central Canada will bring the slight chance (10%)
for an isolated shower along the International Border, but current
HREF and HRRR analysis has the bulk of precip chances remaining well
to the north of the border. Main impacts through the short term will
be tied to the smoke.
.LONG TERM...(Friday through Wednesday)
Issued at 302 PM CDT Wed Sep 6 2023
Key Messages:
-Seasonal temperatures through the long term, with further smoke
chances end of this work week.
-Passing system will bring chances for precipitation and isolated
storms Friday evening and overnight.
Discussion:
Continued NW flow aloft will bring the chance for passing systems
that travel along the Ridge aloft. The main chance will be Friday
afternoon through Friday night as a passing system tracks south of
the region. Probabilities of seeing 0.25 inches or greater over 24
hours are 20-40% for areas south of I-94 and 20% north of I 94. To
increase those probabilities the system would need to tap into
further Gulf of Mexico moisture and track further north. At this
time those probabilities are 20%. If this where to happen we could
see closer to the 0.50 inches for precipitation over 24 hours. The
NW flow aloft helps to limit the available CAPE and moisture from
the Gulf of Mexico. There is slight CAPE (500-1000 J/kg) and shear
aloft (20-30kts) to sustain embedded thunderstorms at times. This
brings the chance for slightly higher amounts over 0.25 inches on an
isolated basis.
Smoke will continue to linger across the area Friday, but should
remain further aloft than at the surface for a majority of the day.
As the system shifts through, near surface smoke concentrations
increase before clearing out. Timeframe of this happening is medium
in confidence. Right now it looks to be around the evening and
overnight hours Friday.
There is little to no change to the pattern aloft over the weekend
and into the new work week. With that being said, temperatures will
be reflective of the pattern. Daytime highs over the weekend and
into the new work week will remain around seasonal averages. Impacts
remain low through the long term.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 631 PM CDT Wed Sep 6 2023
Once the MVFR cloud deck clears at KBJI, the rest of the night
will be quiet. The only potential impact would be late night fog
at KBJI.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...Godon
SHORT TERM...Spender
LONG TERM...Spender
AVIATION...Godon
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
718 PM CDT Wed Sep 6 2023
.SYNOPSIS...
Issued at 718 PM CDT Wed Sep 6 2023
Cooler weather is expected the next several days. Expect highs
from the mid 70s to around 80 and lows in the 50s to around 60
through Sunday. Mostly cloudy skies will continue for much of the
area into Thursday.
&&
.UPDATE...
Issued at 718 PM CDT Wed Sep 6 2023
Expansive area of stratocumulus covers most of the forecast area
this evening except southeast of a Danville-Shelbyville line, and
that should fill in as well over the next several hours. Some
light drizzle/sprinkles have been occurring as well, with latest
HRRR suggesting this may continue for a few more hours.
Main concern will be with the cloud cover. In-progress balloon
sounding from our office shows a fairly deep moist layer beneath
the inversion, and forecast soundings off the NAM and HRRR models
don`t show a lot of improvement through at least midday tomorrow.
Sky cover has been bumped up to go mostly cloudy across most of
the forecast area through Thursday.
Geelhart
&&
.DISCUSSION...
Issued at 232 PM CDT Wed Sep 6 2023
Key Points:
* Cooler temperatures are on track for the next several days, and
likely through next week
* Next chances for precipitation look to be late Monday or Tuesday
A cold front is currently just northwest of Lawrenceville, heading
eastward, with the cooler air mass behind it poised to spread across
the area tonight and remain entrenched over the area for most of the
next week and likely more. Extensive low level cloud cover lingers
behind the front, and looks to continue to circulate around the
upper Midwest and Illinois through Thursday as cyclonic flow
associated with the low currently over the upper Great Lakes
continues until the low heads far enough east late tomorrow. Behind
this feature, high pressure will dominate through the weekend until
an upper trough and cold front arrive early next week. Currently
this looks to be associated with minimal instability and
consequently minimal thunderstorm activity.
High temperatures look to run from the mid 70s to around 80 through
Sunday, with lows in the 50s to around 60. Temperatures look to fall
off a few more degrees after the cold front early next week. The
Climate Prediction Center highlights a 50-60% chance of below normal
temperatures Tuesday through Saturday.
37
&&
.AVIATION... (For the 00z TAFs through 00z Thursday Evening)
Issued at 620 PM CDT Wed Sep 6 2023
Fairly expansive area of MVFR ceilings across central Illinois at
early evening, expected to reach KCMI toward late evening. While
some improvement is expected for a time during the night, another
surge of lower ceilings should drop southward. Best chances of
ceilings below 2,000 feet appear to be from KBMI-KDEC eastward,
and would likely last to around midday. There is some question as
to how much of the cloud cover will break up in the afternoon,
though, so MVFR conditions in eastern Illinois may linger longer.
West winds are settling down a bit and will gradually shift to the
northwest this evening, but will generally be near 10 knots much
of the period.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion...UPDATED
National Weather Service Indianapolis IN
820 PM EDT Wed Sep 6 2023
.Forecast Update...
Issued at 820 PM EDT Wed Sep 6 2023
The limitations of ingredients-based approach to forecasting is on
full display this afternoon. Moderate CAPE driven by warm/moist low
levels beneath poor midlevel lapse rates and extensive dry air
leading to entrainment usually doesn`t support robust convection.
Convective showers forced by frontal convergence have struggled to
attain enough depth for lightning even. What has formed should move
steadily eastward over the next few hours. A cooler post-frontal air
mass should bring us to the low to mid 60s for lows by daybreak.
Trajectories behind the front should shunt wildfire smoke southwest
of the area, though many sites in central Illinois have seen slight
visibility reductions. This is slightly north of what is modeled by
HRRR smoke model, and so some minor visibility reductions may occur
later tonight.
&&
.Short Term...(This evening through Thursday)
Issued at 245 PM EDT Wed Sep 6 2023
The rest of this afternoon and into the evening...
Current satellite imagery depicts a surface low across the Great
Lakes Region with a cu field developing across western portions of
Indiana. This is occurring ahead of an approaching cold front associated
with the low and suggest some destabilization has occurred this
afternoon. Further destabilization ahead of this front should support
modest instability across much of central IN. This along with low-level
convergence will promote scattered showers and storms later this afternoon.
Severe weather is not expected due to weak deep-layer shear, but a
few storms could contain gusty winds. Any convection that develops
is expected to diminish by the late evening hours as the front moves
east.
Tonight through Thursday...
A cooler-drier airmass filtering in behind the front will result in
quiet weather conditions overnight. Look for skies to clear out
early tonight from west to east. However, guidance shows low-level
moisture wrapping around the surface low and advecting into central
IN late tonight beneath a subsidence inversion. This will likely
result in a low stratus deck. Clouds may briefly mix out during the
morning, but mostly cloudy skies are expected for much of Thursday.
Forecast soundings show there may be just enough moisture and
marginal forcing to squeeze out a few showers. Decided to add in
slight POPs for portions of the area due to this. Cold air advection
combined with cloud cover will greatly limit diurnal heating. Highs
will likely only reach the low-mid 70s across most locations.
&&
.Long Term...(Thursday night through Wednesday)
Issued at 245 PM EDT Wed Sep 6 2023
Much of long term will remain in a stagnant upper level pattern
blocked by strong height anomalies to the north, pushing the upper
level jet northward. This should leave the Ohio Valley in a cooler
region beneath low heights. The centroid of lower heights will shift
slightly eastward with time, but high pressure over the lower
Canadian Provinces should induce easterly flow keeping the
subseasonal temperatures over Indiana. The current expectation is
for the coldest day to be Friday (low 70 highs), with a slow warm up
into early next week (mid to upper 70 highs).
Weak flow will hinder any moisture return behind Today`s frontal
passage, keeping conditions dry through at least the Weekend. Some
ensemble members are picking up on the development of a modest low
level short wave passing through the central CONUS early next week.
This could lead to some rainfall late Monday through Tuesday, but
confidence is low given the weak mid to upper level dynamics and
plenty of ensemble spread with both location and magnitude.
Another impending factor will be the westward approach of TS Lee in
the Western Atlantic and its associated impacts on the upper level
pattern. In most instances warm core systems tend to impede pattern
progression until extratropical transition occurs. This could keep
the cooler than normal conditions over central Indiana into the
later portions of next week.
&&
.Aviation...(00Z TAF Issuance)
Issued at 515 PM EDT Wed Sep 6 2023
Impacts:
* Wind gusts up to 25 knots subsiding early this evening
* MVFR ceilings developing late tonight and persisting much of
Thursday
Discussion:
Isolated showers and thunderstorms near/ahead of the cold front
should be east of TAF sites at the start of the TAF period or
shortly after. Post-frontal winds will veer slightly to westerly and
eventually northwesterly. Residual moisture and a second upstream
shortwave trough will result in stratus later tonight through much
of tomorrow. Forecast confidence is moderate to high. Ceiling
heights may vary some from current indications, but probably still
within MVFR.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Update...BRB
Short Term...Melo
Long Term...Updike
Aviation...BRB
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
652 PM CDT Wed Sep 6 2023
.SHORT TERM...(This evening through Thursday night)
Issued at 256 PM CDT Wed Sep 6 2023
KEY MESSAGES:
- Noticeably cooler air to remain in place starting today.
- Smoke and haze continue to impact western Minnesota, but conditions
will improve Thursday morning.
Surface analysis this afternoon shows a north-south oriented area of
high pressure arriving from the northwest, which when combined with
a more pronounced northerly flow aloft is bringing much cooler air
to the Upper Midwest which will remain in place until further
notice. The axis of the high pressure area will shift east to the
Mississippi River by Thursday evening, then over WI/IL by Friday
morning. There is a stubborn-to-clear swath of low stratus over
eastern MN into western WI, resulting in keeping temperatures this
afternoon in the low-mid 60s while western MN where clear skies have
emerged, highs have reached the lower 70s. The cloud shield will
slowly erode eastward tonight through tomorrow, making for a bit of
a gradient for low temperatures tonight. Lows will range from the
mid 40s in western MN to the mid 50s in eastern MN into western WI.
The clouds are even looking likely to hold on in western WI tomorrow
as consensus model highs in western WI will run in the mid-upper 60s
while all of central-southern MN will range through the 70s.
Clearing skies Thursday night into Friday morning will result in
another cool night with lows ranging from the lower 40s in western
WI to the lower 50s in western MN. In terms of any sensible wx, near-
surface smoke will continue to be an issue in western through
southwestern MN into tonight, bringing visibilities down to the 4-
6sm range here and there. Conditions will improve tonight as
northerly winds push the smoke out of the area and upper level flow
cuts off any additional smoke from impacting MN/WI. Secondly, under
the low stratus, patchy drizzle is possible but very few sites have
reported as such so have kept the short-term forecast dry.
.LONG TERM...(Friday through Wednesday)
Issued at 256 PM CDT Wed Sep 6 2023
Key Messages:
- A chance for showers on Saturday night into Sunday, otherwise near
normal temperatures through the middle of next week.
Discussion... A relatively quiet period is upon us into the weekend
and next week with the exception of a chance for scattered showers
arriving late Saturday into Sunday along a passing weak cold front.
Substantial rainfall is not expected, with only a few thunderstorms
possible amidst weak instability due to a much cooler overall
environment compared to that which we are used to at this point. A
few areas could see a couple tenths of an inch of rainfall overnight
through early Sunday, at which point the front pushes through the
region and leaves us dry through the middle of next week. Broad high
pressure and upper level ridging settles in behind the departing
front centered over the northern Great Lakes, which for us will mean
continued near to slightly below normal temperatures which will be a
welcome break from the heat and humidity we`ve experienced through
the month thus far. Temperatures generally peak in the low 70s with
lows in the 50s, and this forecaster is excited to open up some
windows and enjoy the fresh cool air.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 624 PM CDT Wed Sep 6 2023
Clearing line near a STC to MKT line at the start of this period is
expected to move little overnight and may even push back west a
little, which is why we have the clouds leaving MKT for a bit,
before returning again later tonight. West of the stratus, there`s
increasing concern we`ll see fog develop, so introduced that
potential to AXN/RWF. Thursday, it will just be a slow go to clear
the clouds, with EAU likely remaining cloudy all day, though
hopefully with heights improving to VFR in the afternoon.
KMSP...Looking at forecast soundings, the RAP & NAM keep clouds at
MSP through about 20z, the GFS until would have them gone well before
18z. Current TAF follows more along the GFS line, but we are getting
into the season where it gets harder and harder to clear out
statocu...
/OUTLOOK FOR KMSP/
Fri...VFR. Wind SE 5-10 kts.
Sat...VFR. Chc -SHRA overnight. Wind SW becoming NW 5-10 kts.
Sun...Mainly VFR. Chc MVFR/SHRA early. Wind N 10 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&
$$
SHORT TERM...JPC
LONG TERM...TDH
AVIATION...MPG
...Updated Aviation Forecast Discussion...
.DISCUSSION...
Issued at 225 PM CDT Wed Sep 6 2023
Key Messages:
- Unhealthy air quality due to wildfire smoke through Thursday
morning.
- Several shower and thunderstorm chances through the forecast. A
strong storm or two is possible Thursday evening over northeast
NE.
- A bit warmer Thursday-Saturday, then trending cooler into early
next week.
This afternoon into Thursday night:
Widespread smoke is being observed across the area today, leading
to reduced visibilities and unhealthy air quality. Latest HRRR and
RAP forecasts suggest that similar conditions will persist into
tonight with gradually improving conditions by Thursday morning
over western IA and far eastern NE. Smoke concentrations will
continue to diminish Thursday afternoon into Thursday night as
winds change to more of a southeasterly direction. An Air Quality
Alert remains in effect until noon Thursday, and sensitive groups
are encouraged to avoid prolonged outdoor exposure for the next 24
hrs or so.
A shortwave trough over the Sierra Nevadas early this afternoon is
forecast to move into western parts of NE and SD Thursday
afternoon, and eventually the mid-MO Valley Thursday night.
Steepening low/mid-level lapse rates and increased forcing for
ascent preceding that upper-air system are expected to foster
widely scattered showers and thunderstorms over portions of north-
central NE Thursday afternoon. That activity is forecast to spread
southeast into our area late Thursday afternoon into Thursday
night. Model soundings suggest that a relatively dry boundary
layer over our area will limit the degree of air mass
destabilization with maximum MUCAPE values remaining less than
1000 J/kg. However, the presence of the steep lapse rates and
modest cloud-bearing shear could support a strong storm or two
capable of hail up to 1" and/or gusty winds over parts of
northeast NE late Thursday afternoon into evening.
In regard to temperatures, we expect overnight lows in the mid
40s to mid 50s with highs Thursday in the upper 70s to mid 80s.
Friday into early next week:
In the wake of the Thursday night shortwave trough (mentioned
above), the 12z global models indicate that midlevel heights will
build over the northern and central Plains Friday into Saturday.
Accordingly, we expect slightly warmer temperatures with afternoon
highs in the 80s. By Saturday afternoon into early next week, a
series of midlevel disturbances tracking through the northern
Plains into the Great Lakes will promote the amplification of a
broader-scale trough from the Great Lakes into Ozarks. As a
result, cooler conditions are expected with highs mainly in the
70s.
The forecast will indicate increasing rain chances Friday night
into Saturday over northeast NE as a surface front settles into
the area. The front is expected to continue south through the
remainder of the area Saturday night into Sunday with an
associated chance of showers and thunderstorms areawide. Another
midlevel disturbance will glance the region Sunday night into
Monday with rain chances continuing through that time frame.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1029 PM CDT Wed Sep 6 2023
Visibility has improved this evening after sunset, hovering around
5-6 sm. This should persist overnight into Thursday morning. We`ll
likely see improving conditions through the day on Thursday as a
shift to east then southeasterly winds should help to clear out
the smoke. Confidence in timing is low, though. We`ll see a few
thunderstorms develop Thursday evening after 00Z. Confidence is a
little higher that storms will impact KOFK, so have added a window
to the TAFs, but timing may shift. Less confident in timing or
storms impacting KOMA and KLNK at all.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.
&&
$$
DISCUSSION...Mead
AVIATION...McCoy
Area Forecast Discussion
National Weather Service Nashville TN
842 PM CDT Wed Sep 6 2023
...New UPDATE...
.UPDATE...
Issued at 839 PM CDT Wed Sep 6 2023
Latest radar shows just one tiny shower currently in our forecast
area in far southern Cumberland County, with the bulk of the
afternoon thunderstorms activity now to our south in MS/AL.
However, a new line of showers and a few thunderstorms has formed
along the main cold front which stretches from east of Paducah to
near Jackson TN. HRRR shows this activity moving into and across
at least our northern counties this evening, with additional
showers and storms possibly popping up as well. Therefore have
adjusted pops upward across our northern half for this evening,
then decreasing rapidly from west to east from late evening into
the overnight hours. Some fog will also be possible overnight
where clouds can clear out sufficiently, but right now looks to
remain patchy at best. Rest of forecast is generally on track and
only made minor tweaks.
&&
.SHORT TERM...
(This afternoon through Thursday Night)
Issued at 205 PM CDT Wed Sep 6 2023
Much needed rain finally showed up today across Middle TN. A few
spots saw healthy totals with northeast Robertson coming in as
the morning winner (2.5 to 3 inches) and many spots along and
north of I-40 scored with a half to inch and a half. The rest of
Middle TN should be in for the rain this afternoon/early evening.
Over the last couple of hours, clouds have started to clear out
over West TN and west central Middle TN. This has allowed
instability to grow ahead of a shortwave that has just moved
through Memphis. This shortwave should spark convection (cloud
growth is being seen this hour along that shortwave) and give the
rest of Middle TN the rain they deserve, too. The question is,
will we get severe weather? Forecast shear values aren`t near as
high as we thought they would be, with latest RAP analyses only
coming in around 25 kts. This should be enough for thunderstorms,
but I don`t think it`s enough for any widespread organization. For
this reason, we`re going to hold firm with this morning`s
messaging: one or two strong storms will be possible with gusty
winds and heavy rain with the focus being south of I-40 and west
of I-65. Precipitation should be out of Middle TN before midnight,
then...
&&
.LONG TERM...
(Friday through next Wednesday)
Issued at 205 PM CDT Wed Sep 6 2023
A fantastic rest of the week is in the cards. Dew points will fall
over the next 18 hours as dry air filters into the region and we can
expect afternoon highs in the low to mid 80s for the next few days.
The only wild card will be Friday as an upper low is expected to
swing through the region -- however, models are depicting this to be
a dry frontal passage and should only act to reinforce the dry air
for this weekend.
Our next shot a rain may be as far away as next Tuesday, but
temperatures should moderate a little by the end of the weekend and
into Monday with the mercury trying to get back to normal. All in
all, the next several days look really good for the mid-state.
&&
.AVIATION...
(00Z TAFS)
Issued at 703 PM CDT Wed Sep 6 2023
VFR and dry conditions are expected at airports at the beginning
of the TAF period, before VCSH/VCTS impact CKV/BNA/MQY from
02-06Z. After then, fog will bring IFR/LIFR conditions to CSV/SRB
overnight. All airports will return to VFR after 13Z on Thursday
morning. Light south to southwest winds this evening will veer to
northwest overnight with fropa.
&&
.PRELIMINARY POINT TEMPS/POPS...
Nashville 68 84 63 83 / 30 0 0 0
Clarksville 65 83 59 82 / 40 0 0 0
Crossville 64 78 57 78 / 30 0 0 0
Columbia 67 84 59 83 / 20 0 0 0
Cookeville 66 80 59 79 / 30 0 0 0
Jamestown 65 78 58 77 / 30 0 0 0
Lawrenceburg 67 84 59 82 / 20 0 0 0
Murfreesboro 67 86 61 85 / 30 0 0 0
Waverly 64 84 59 82 / 30 0 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE.......Shamburger
SHORT TERM...Unger
LONG TERM....Unger
AVIATION.....Shamburger
Area Forecast Discussion
National Weather Service Paducah KY
605 PM CDT Wed Sep 6 2023
.UPDATE...
Issued at 605 PM CDT Wed Sep 6 2023
Updated aviation discussion for 00z TAFs.
&&
.SHORT TERM...(Today through Friday night)
Issued at 304 AM CDT Wed Sep 6 2023
This afternoon and tonight...A surface cold front will continue to
progress through the forecast area through late this afternoon into
tonight. Satellite imagery shows a fairly widespread cumulus field
developing ahead of the front. While shear remains quite weak, the
latest mesoanalysis data from the RAP shows about 1500-3000 J/kg of
SBCAPE over most of the forecast area. The parent surface low
remains well to our north across southern Wisconsin, so forcing is
also on the weak side.
Putting it all together, expecting isolated to widely scattered
showers and thunderstorms to develop through the rest of this
afternoon into early this evening, mainly over the Wabash River
Valley and southward into the KY Pennyrile. SPC still has a marginal
risk of severe convection in the HOP area for isolated damaging wind
gusts, but even this may be overdone at this point.
By 06z Thursday, the front and any associated precipitation will be
east of the CWA. Post-frontal CAA, will bring a refreshing airmass,
with low temperatures dipping into the lower to middle 60s and
falling dew point temperatures. Can`t rule out some patchy fog
around daybreak as well in locations that have seen rain in the last
couple of days.
Thursday and Friday...Pleasant early autumn weather will arrive for
the end of the work week. Models are in strong agreement that mild
Canadian high pressure will shift southward into the Midwest. Did
increase cloud cover slightly for Thursday to the potential for some
high level Canadian wildfire smoke to accompany the surface high.
Thursday will see mostly sunny conditions with high temperatures
reaching the upper 70s to lower 80s...along with refreshingly lower
humidity levels. Thursday night will see continued quiet weather
with low temperatures dipping into the middle to upper 50s.
Friday will see a slightly more complicated setup. Models show a
shortwave trough diving south-southeast from the central Plains
through the Ozark Plateau, along the potential for a complex of
thunderstorms. The eastward progression of the trough will be
blocked by a stout, elongated H5 ridge over the Eastern Seaboard.
The end result should be another dry, pleasant, and low humidity day
Friday for the forecast area, though cloud coverage will be somewhat
higher. High temperatures will again reach the upper 70s to lower
80s and dip into the upper 50s to lower 60s on Friday night.
.LONG TERM...(Saturday through Wednesday)
Issued at 304 PM CDT Wed Sep 6 2023
Ridging is expected continue building through Saturday bringing
relatively cooler and drier air throughout the region with high
temperatures in the mid-80`s and dewpoints in the mid- to low-50s.
This forecast seems likely to persist through at least Monday
with some additional warming in to the low-90s.
This weekend`s forecast is primarily driven by an amplified ridge
over AZ/NM. The long term agreement amongst ensemble guidance on
the evolution of this process is relatively good, with the ridge
eroding and propagating south. In its wake, weak zonal flow will
prevail over the Central CONUS with a speed max over CO/KS.
However, from this point the picture muddies back up as spread
increases between members due to this weak feature potentially
phasing with a sagging mid-level trough to the north. This is only
compounded due to the future influence of the soon-to-be
Hurricane Lee. Nonetheless, some precipitation seems likely
throughout the CWA next Tuesday/Wednesday with the specific
timing and intensity being to early to really pin down.
After the frontal passage Wednesday we will resume our regularly
scheduled ridging. Temperatures will likely be seasonably cool in
the 70`s and quite dry. Confidence is relatively high for this
forecast in spite of the comments above, mainly due to a pattern
suggestive of dominant ridging in the wake of a strong, recurving
hurricane plus a fresh FROPA.
&&
.AVIATION...
Issued at 605 PM CDT Wed Sep 6 2023
A cold front is currently moving across portions of the region
with some gusty NW winds. Brief wind gusts near 20 kts are
possible at terminals KEVV & KOWB this evening before winds turn
light and variable tonight. While skies will initially clear,
mid-level clouds will return overnight, especially across northern
terminals as some stubborn residual moisture lingers.
The only real concern for late tonight is the potential for some
patchy fog. Winds should remain elevated enough to limit this to
typical climatologically favored locations. Have included a TEMPO
group with BCFG mention at KCGI where guidance is hinting at the
greatest risk.
For Thursday, VFR conditions expected with some lingering mid-
level clouds across the north. Northwest winds between 5 to 10 kts
are expected.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...DW
SHORT TERM...DWS
LONG TERM...JAB
AVIATION...DW
Area Forecast Discussion
National Weather Service Springfield MO
610 PM CDT Wed Sep 6 2023
Key Messages:
1. Canadian wildfire smoke has pushed into the area and will
continue over the area through at least Thursday.
2. Shower and thunderstorm chances return late Thursday night into
Friday.
3. Weekend looks mostly dry with precipitation chances returning
early next week.
.SHORT TERM...(This evening through Thursday)
Issued at 201 PM CDT Wed Sep 6 2023
Smoke from the Canadian wildfires was beginning to move into the
Missouri Ozarks and southeast Kansas. Some visibility has already
been reduced over Western Missouri and southeast Kansas today.
HRRR and RAP13 vertically integrated smoke products continue to
bring additional smoke over the area tonight and Thursday and will
be adding to the grids/forecast/graphics with this forecast
package.
An upper level area of high pressure was located over southwest TX
with the ridge axis extending north of the high pressure center
into the Rockies. Northwest flow was located over the plains into
the mid Mississippi valley. Water vapor was showing a shortwave
over Nebraska and this shortwave is expected to dive southeast
into the area tonight. Moisture will be quite limited, so we do
not have any precipitation chances for tonight. Hazy/smokey
sunshine is expected on Thursday with highs from the low 80s in
the northeast to around 90 in the west.
.LONG TERM...(Thursday Night through Wednesday)
Issued at 201 PM CDT Wed Sep 6 2023
Moisture should start to increase in the west on Thursday night
and another shortwave will dive southeast into the area late
Thursday night into Friday. This will bring the next chance of
showers and thunderstorms to the area, mainly affecting the
western half to 2/3 of the CWA. Precipitation should exit to the
south by late Friday afternoon with generally dry conditions
expected for Friday night through much of Sunday night.
Temperatures over the weekend should dip into the low to mid 80s
for highs and the mid to upper 50s for lows.
Showers and thunderstorms will be possible in the early part of
next week as a deeper trough and several waves of energy move into
the region.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 609 PM CDT Wed Sep 6 2023
Wildfire smoke from the north-northwest will continue to filter
south into the area this evening into Thursday morning and could
slightly reduce visibilities across the area this evening into
Thursday morning. MVFR conditions will be possible at the TAF
sites this evening into Thursday morning. Winds will be light but
turn northerly and be light tonight into Thursday. Skies will be
clear.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Lindenberg
LONG TERM...Lindenberg
AVIATION...Wise