Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/05/23
Area Forecast Discussion
National Weather Service La Crosse WI
1048 PM CDT Sun Jun 4 2023
.DISCUSSION...(This evening through Sunday)
Issued at 301 PM CDT Sun Jun 4 2023
Key Messages:
- Smoke has moved over portions of the area, with possible
impacts to sensitive groups.
- Shower and storm chances return again for Monday and Tuesday.
- More seasonable temperatures return midweek, with the next
chance for showers and storms looking to be towards the end of
the week into next weekend.
Today - Tonight: Smoke & Air Quality Advisories
Overall, the upper level pattern remains, with the upper level high
continuing to drift westward over the north-central U.S. and south-
central Canada. The northeasterly flow has allowed smoke from
wildfires in Quebec to work its way into parts of the local forecast
area. Smoke reaching the surface has resulted in slightly reduced
visibility (5-6sm) across many of our Wisconsin counties including
here locally in La Crosse. Some indication in the HRRR and RAP that
smoke/haze may remain possible through the overnight, so will
continue the mention in the forecast for areas most impacted. Of
note, the WI DNR and Minnesota Pollution Control Agency has issued
an Air Quality Advisory for fine particle pollution through Monday
morning as the smoke is impacting PM2.5 concentrations at the
surface. The air quality index is expected to range from "Unhealthy
for Sensitive Groups" level to "Unhealthy" level in Wisconsin and
"Unhealthy for Sensitive Groups" category for Minnesota. Precautions
should be taken if planning to be outside this afternoon and
evening.
Monday - Weekend: Shower and Storm Chances, More Seasonable Temps
Through the medium range, models are in good agreement on an upper
level blocking type pattern, with the upper ridge remaining over the
Northern Plains/central Canada between troughing/lows over the
northeast and California. A shortwave trough is expected to move
through this (NE/Mid-Atlantic) troughing, with a surface front
dropping down across the region through the day on Monday. This
should provide our next focus for shower and storm chances into the
start of the new week. It looks like there have been some slight
timing (of the front/precip) and coverage (precip) differences that
guidance continues to resolve. Even so, latest runs of the hi-res
model guidance would suggest precipitation may begin to move into
northern portions of the area by Monday morning. How much further
south and east this precipitation makes it becomes the challenge, as
guidance suggests drier air advecting from the east along with
mixing could work against convection. With this, confidence would be
higher for increased shower and storm chances in the north/west
where more moisture and instability remain per model guidance and
soundings. As far as QPF, by Tuesday morning the 04.12Z HREF 24-hr
QPF ensemble probability matched mean ranges from 0.1 to 0.25
inches, with spotty areas of 0.5 to near 1 inch mainly again across
the north/west.
This surface boundary looks to possibly stall for a time, with
shower and storm chances remaining into the day on Tuesday mainly
across southeast MN and northeast IA. Have continued the trend in
increased temperatures for Monday. However, depending on the timing
of the frontal boundary, adjustments down may be needed especially
across our northern counties. The boundary looks to be pushed out of
the area Wednesday, with more seasonable temperatures and drier air
looking to return behind it. This could bring some concerns as
minimum afternoon relative humidity values drop into the low 20s to
low 30s across the forecast area. Still some details to work out in
the long term, but waves of shortwave energy/surface fronts may
provide some focus for further shower and storm chances across the
area heading into the weekend. Lower confidence this far out, so
will continue to monitor trends for now.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1048 PM CDT Sun Jun 4 2023
MVFR visibilities still being observed across mainly Wisconsin this
evening from Canadian wildfires as smoke rotates around large
blocking high. Short term guidance suggests perhaps some improvement
or mixing overnight but with many areas still calm, will keep with
persistence at least for KLSE.
With trends of ridge retrograding west somewhat, will still be
watching cold front move through Great Lakes will bring an increase
in mainly mid level clouds and subtle wind shift on Monday. Boundary
could be just enough to focus a few showers or isolated
thunderstorms as well but given lower confidence /10-20%/ of any
impacting TAF sites, will keep them out for now.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
DISCUSSION...EMS
AVIATION...Shea
Area Forecast Discussion
National Weather Service Binghamton NY
953 PM EDT Sun Jun 4 2023
.SYNOPSIS...
An upper low over the Northeast will keep temperatures near to
below normal for early June. This feature will also bring
showers from time to time, primarily from Monday night through
the rest of the work week.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
950 PM Update...
Clouds are lingering longer from Binghamton east into the
Catskills this evening, so sky grids were adjusted along with
hourly temperatures remaining a bit warmer than expected.
Otherwise, with each run of the HRRR model showing extensive,
and a high concentration of vertically integrated smoke over
much of CNY and NE PA on Monday, went ahead an added in
haze/patchy smoke into the weather grids through the day. There
remains uncertainty on if any of this smoke will mix down
closer to the surface, or remain fully aloft.
650 PM Update...
Some clouds moved in from the east, back to the I-81 corridor
as expected. These will gradually scatter and dissipate heading
into the overnight period. It will be cool tonight, but not
quite as cold as last night...look for lows mainly in the 40s
areawide; can`t rule out isolated upper 30s in the normally
colder locations of Oneida county and Catskills.
Other feature of note on the satellite is the extensive smoke
aloft over Ontario, extending south into western NY/PA at this
time. HRRR and RAP smoke model guidance shows the flow backing
more northerly on Monday, with plenty of smoke aloft likely
settling over CNY and NE PA...NW of Binghamton at daybreak, then
spreading east to cover most of CNY and NE PA except the Catskills
& Poconos by late morning. The main impact from this will be to
turn the sky a milky, hazy white color. Otherwise, Monday is
partly sunny and mild with highs in the 70s. There will be a bit
of a north-NW breeze at 8-15 mph and a few gusts around 20 mph.
Other minor adjustment with this update was to slow down the
PoPs coming in from the north Monday evening. There still does
look to be a chance for showers and a slight chance for
thunderstorms...but now it is looking like Monday night, and
holding off until after midnight or predawn hours for the Twin
Tiers region and NE PA.
2 PM Update...
An upper low centered near the Gulf of Maine will continue to
influence our CNY/NEPA weather through tomorrow night. Tonight
and much of Monday will remain rain free due to a very dry
boundary layer, limited moisture aloft and essentially no
forcing. Our eastern zones will experience clouds on the
periphery of the low into this evening, then partial clearing.
Temperatures will be below average for the time of year as
cooler air is reinforced on northerly winds.
From later Monday into the night...shower chances will increase as
the broad upper low retrogrades slightly and spins energy and
deeper moisture around the system. Scattered showers seem
plausible, although QPF should be on the light side as there is
still dry air in the lower atmosphere to overcome.
&&
.SHORT TERM /TUESDAY/...
240 PM Update...
Broad upper level low off the coast of Maine provides enough
moisture and lift to kick off rain showers Tuesday
afternoon/evening. This lift can be seen at the 500 mb level with
GFS & RGEM showing a vort max over our area. Moisture is present at
the 850 and 500 mb levels. Models suggest instability with these
showers as low level lapse rates are present with CAPE values
reaching approximately 300 J/KG. GFS & NAM inverted v soundings show
upper level winds mixing down to the surface with 30 kts of 0-6 km
bulk shear. These parameters suggest gusty winds and small hail are
possible with any storms that do develop. The influence of the upper
level low keeps temperatures cool on Tuesday with highs ranging from
65-75. The cool pattern carries over into the night with
temperatures falling into the 40s.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
240 PM Update...
Wednesday through Friday remains under the influence of the upper
level low as it starts to spin over Maine and Nova Scotia bringing a
few rounds of showers throughout this period. Since yesterday the
position of the upper level low has shifted eastward slightly
distributing showers further into our region. Despite this QPF
continues to look rather light given the continued lack of deep
moisture though. This upper level low will continue to bring in a
more chilly airmass into the region with highs only getting into the
60`s and 70`s and lows falling into the 40s. Upper level low shifts
eastward Friday with high pressure building in behind it. Southerly
flow returns Saturday advecting warm air into our region allowing
temperatures warm into the mid/upper 70s.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
720 pm update...
VFR will continue for the next 24 hours. A 6k ft ceiling will
continue at KBGM and KRME until 01 or 02z. Otherwise high clouds
will slowly move south into the area tonight and Monday.
Winds becoming light and variable by 02z. Monday Northwest to
north winds increase to 10 kts by 15z. Probably some gusts to 15
to 20 kts in the afternoon.
Outlook...
Monday night through Friday...Mostly VFR; Chance for showers
each day, which may lead to brief restrictions.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...None.
&&
$$
SYNOPSIS...AJG/JAB
NEAR TERM...AJG/JAB/MJM
SHORT TERM...ES
LONG TERM...ES
AVIATION...TAC
Area Forecast Discussion
National Weather Service Burlington VT
952 PM EDT Sun Jun 4 2023
.SYNOPSIS...
A trough of low pressure will continue to influence the weather
across our region through early this upcoming week. A few light rain
showers are expected over eastern Vermont tonight, followed by a
mostly dry Monday with comfortable temperatures. Additional showers
with areas of smoke are anticipated for Tuesday into Wednesday of
this upcoming week with temperatures 5 to 10 degrees below normal
for early June.
&&
.NEAR TERM /THROUGH MONDAY NIGHT/...
As of 949 PM EDT Sunday...The evening update is in solid shape.
Again, made some manual tweaks to PoPs to best capture the area
of showers in central Vermont based on radar that has been
decreasing in extent and strength of radar returns. Otherwise,
all else is on track this evening. Have a great night!
Deep closed mid/upper lvl circulation conts to spin near the
southern Maine Coast, while ribbons of enhanced mid lvl moisture
advects back toward eastern VT. Radar conts to support on and
off light rain showers, mainly east of the Greens, which based
on progged rh fields and qpf placement wl continue thru 03z,
before slowly shifting eastward. Any qpf wl be <0.10 thru the
overnight hours. Clouds wl once again influence temps tonight
with clear skies and lighter winds acrs the northern NY. Have
lows in the lower 30s to mid 40s acrs the region, coolest west
and warmest east/cpv. Winds should decrease slowly overnight and
become north/northeast at 4 to 8 mph.
On Monday, little change is noted in the large scale pattern with
closed cyclonic circulation to our east, while deep dry layer is
located to our west, with approaching s/w energy in the nw flow
aloft. This s/w energy is responsible for scattered convection today
south of Hudson Bay and north of the Great Lakes wl approach our cwa
around 12z Monday with additional energy arriving toward 00z.
However, given deep dry layer and energy shearing apart in the
confluent flow aloft, have kept Monday mostly dry attm. Better
forcing and slightly better moisture arrives toward 00z Tues with
2nd vort, so have increased pops to chc acrs northern NY aft 00z
Tues. Instability is rather limited as sfc heating is waning, but a
rumble of thunder is possible, mainly SLV/Western Dacks thru 03z.
In addition, have noted RAP/HRRR vertically integrated and sfc smoke
progs suggest smoke from over 2 dozen wildfires in Quebec Province
moves toward northern NY by 12z Tues as flow becomes
north/northwest. Its interesting to note both RAP and HRRR show
potential sfc vis <3 miles is possible for the SLV near sunrise on
Tues. However, it should be noted fcsting smoke and potential
impacts is extremely difficult and so therefore have just mention of
patchy smoke in the fcst for now. Highs with more sun on Monday
should rebound back closer to normal, except still below for eastern
sections due to more clouds, with values mid 60s to mid/upper 70s.
Lows on Monday night mainly in the lower 40s to lower 50s.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
As of 301 PM EDT Sunday...A shortwave will begin to phase the a
stacked low pressure system near Nova Scotia on Tuesday. As the
shortwave energy interacts with the low, a bit of a Fujiwara effect
will occur causing the low to retrograde westward toward the North
Country. The combination of these two features will help increase
precipitation chances across the region, especially in the Tuesday
afternoon and evening timeframe. Cooling temperature aloft and
warming surface temperatures should yield sufficient enough lapse
rates to support some weak surface based instability in the
afternoon which will become elevated in the evening as the boundary
layer decouples. The one negative in this scenario is that this
precipitation begins while we still have a relatively dry air mass
overhead. This may initially lead to a lot of virga depending on
precipitation intensity so we may underperform on rainfall amounts
that we have been seriously lacking as of late.
In addition to the rainfall, it looks like we could have a plethora
of smoke move in from the wildfires across southern Quebec and
Ontario. While the HRRR and RAP barely go out to Tuesday morning,
the signs are there for some significant low level smoke with some
places exceeding 100 micrograms per cubic meter. This could lead to
a degradation in air quality and is something we will be monitoring
closely and we will be working with our partners should we need any
air quality alerts. Stay tuned for more.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
As of 301 PM EDT Sunday...Rain chances will continue each day of the
week as we remain under the influence of a broad upper level trough.
We expect an uptick in shower activity each afternoon as we see
marginal instability amounts develop in response to diurnal heating
but the lack of any deep moisture should likely prevent any
widespread shower coverage. Temperatures though much of the long
term will remain below seasonal normals as we remain under the
influence of the cold core low but we should see temperatures
moderate back to seasonal normals by the end of the weekend. A
strong blocking pattern will remain in place beyond the forecast
period with all ensembles pointing at an anonymously strong blocking
high near Greenland. Other than the potential for smoke, there
appears to be no significant weather in the extended forecast but a
cooler and wetter pattern is sure to be welcomed by many.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
Through 00Z Tuesday...Conditions are mainly VFR, but with
overcast across much of Vermont with ceilings 3000 to 7000 feet.
A few light showers are moving west-southwestwards, but not
impacting ceilings or visibility. Shower activity should
gradually decrease after sunset, but it`s possible a few
additional showers track from the west into our region for a
few more hours. Winds are currently around 7 to 13 knots
sustained from the north or northeast, and will generally
subside overnight and ramp back up to 6 to 10 knots after 12z,
while becoming northwesterly. Ceilings, if any, will trend 5000
to 8000 ft Monday.
Outlook...
Monday Night: VFR. Slight chance SHRA.
Tuesday: VFR. Likely SHRA, Slight chance TSRA.
Tuesday Night: Mainly MVFR, with local IFR possible. Likely SHRA.
Wednesday: Mainly MVFR, with areas VFR possible. Likely SHRA.
Wednesday Night: Mainly MVFR, with areas VFR possible. Chance
SHRA.
Thursday: Mainly MVFR, with areas VFR possible. Chance SHRA.
Thursday Night: Mainly VFR, with areas MVFR possible. Slight
chance SHRA.
Friday: Mainly VFR, with areas MVFR possible. Chance SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Taber
NEAR TERM...Haynes/Taber
SHORT TERM...Clay
LONG TERM...Clay
AVIATION...Haynes
Area Forecast Discussion
National Weather Service Billings MT
646 PM MDT Sun Jun 4 2023
.UPDATE...
Scattered showers and a few weak t-storms continue to impact the
area at 0045z, but we are starting to see the activity lessen as
we move toward sunset (w/ the lack of forcing). Dry conditions
should prevail late tonight and Monday morning as we will be under
the influence of anticyclonic flow associated with strong high
pressure over southern Manitoba and ND. There seems to be a
risk of valley fog late tonight into early Monday mainly west of
Rosebud County, with light winds and clearing skies...along with
anomalously high boundary layer moisture in place. Though previous
runs did not show it, the HRRR is beginning to show fog after
07z. This could potentially impact the Monday morning commute. JKL
&&
.DISCUSSION...
This afternoon through Monday night...
Upper high pressure over the Northern High Plains and general low
pressure over the western United States, will keep the area in
southerly flow aloft. This flow pattern will contain weak
shortwaves for ascent. Combine the weak lift, with ample
atmospheric moisture (precipitable water values around an inch),
will be enough to have high scattered PoPs in the forecast through
the period. Energy and forcing do not look strong enough for
widespread coverage of showers and thundestorms, but central and
western zones look to be most vulnerable for convection the next
couple of days, as these areas will be closer to a small scale cut
off low over Idaho.
This afternoon and evening, short range models develop showers,
with isolated thunderstorms, over the mountains and foothills,
pushing them north through the early evening. Shear is weak, with
skinny cape, so not expecting strong storms. Storms will be
capable of heavy rain with high PWATs, so a quick half inch of
water can not be ruled out. Ground is saturated, so all the rain
should run off today, so heavy rainfall could cause ditches and
small streams to fill up quickly, so be mindful of that should you
be out. The activity will drift into north and northwest zones
and weaken this evening. Monday will be another day of scattered
afternoon and evening convection. Focus of activity will be pushed
a little farther west (primarily over the mountains and
foothills), as weak jet energy weakens and gets pulled north.
Activity will again weaken and drift north into the evening but
may be able to hang on a little longer (into the overnight hours)
over northwest zones. Storms will again have a heavy rainfall
threat, as PWATs remain around an inch. High temperatures will be
in the mid 70s to mid 80s, with the warmest readings over
southeast Montana.
Hydrology: Soils reamin very saturated, so any rainfall will run
off quickly. This means that any strong shower or thunderstorm
will be capable of causing localized flooding, or ponding of
water. Biggest impacts of the convection will be in the small
streams and ditches, as main stem rivers have been handling the
added water well, with all rivers below flood stage. The
Musselshell river at Martinsdale has began to level off a bit and
this trend should continue downstream, which looks to keeps things
below flood stage. Will have to watch this river closely over the
next couple of days, as more rainfall could cause additional
rises into early week. TWH
Tuesday through Sunday...
Not much to change in the going extended forecast. Upper level
troughing will remain anchored over the western United States into
next weekend, as an upper ridge is locked in placed over the
northern High Plains into south central Canada. This pattern will
keep southerly flow in place for daily afternoon and evening
thunderstorm chances. Trying to pin point exact locations of
thunderstorm development will be difficult, but the pattern
dictates a broad brush approach to thunderstorm chances.
Precipitable water amounts will remain locked in place around an
inch, which will lead to easy thunderstorm formation and allow
thunderstorms to pose a heavy rain threat. The first good chance
of convection will start on Tuesday and this will be focused over
western and central zones mainly. Convection chances spread east
into southeast Montana on Wednesday with energy weakening mid
level capping potential. From Wednesday onward, it will be
difficult to identify a specific area for strongest storms so will
go with a broad brush approach.
NBM probabilities were pointing to the Thursday through Saturday
time frame as the greatest risk of getting a half inch or more of
rain in a 48 period, with a 20-40% chance Wednesday-Thursday, a
30-50% chance Thursday-Friday and a 40-60% chance Friday-Saturday.
So the focus seems to have shifted more toward the end of the
week for the best chance of picking up the heaviest rain, and this
due to the upper low kicking out of the west and tying to
undercut the ridge, which blocks energy in southern Montana and
northern Wyoming. Overall, every day will have afternoon and
evening thunderstorms, with the greatest threat for widespread
coverage being from Wednesday onward. Also, every thunderstorm
will have the potential to produce heavy rainfall and localized
flooding. High temperatures will be pretty persistent through the
extended period in the mid 70s to mid 80s, with the warmest
readings over Southeast Montana. TWH
&&
.AVIATION...
Scattered showers and thunderstorms will impact the region thru
around 04z. Local/brief MVFR is possible with these storms, but
the chance of this occurring at a TAF site after 01z is small.
Mountains will be occasionally obscured. VFR will prevail late
tonight thru Monday morning...but there is a risk of localized fog
between roughly 09-15z, mainly west of KMLS. Though confidence is
low, MVFR-LIFR is possible in this area. More showers and
t-storms will develop Monday afternoon, with the focus being over
the mountains and foothills, and locations west of KBIL. JKL
&&
.PRELIMINARY POINT TEMP/POPS...
Mon Tue Wed Thu Fri Sat Sun
-----------------------------------------------------------
BIL 056/082 057/083 059/081 059/082 060/080 060/077 057/077
42/T 24/T 35/T 46/T 56/T 57/T 46/T
LVM 050/079 052/080 054/078 054/077 055/077 053/076 053/074
55/T 27/T 47/T 58/T 67/T 57/T 57/T
HDN 053/085 055/085 058/084 058/084 059/083 059/079 056/079
31/U 12/T 24/T 45/T 46/T 56/T 45/T
MLS 061/087 063/089 063/089 064/088 064/085 062/080 058/080
20/U 01/U 11/U 23/T 45/T 55/T 32/T
4BQ 057/085 059/087 061/087 061/087 060/084 060/077 056/077
20/U 00/U 12/T 23/T 46/T 56/T 34/T
BHK 059/086 058/087 059/087 061/087 060/083 058/078 053/079
20/U 00/U 11/U 12/T 35/T 54/T 21/U
SHR 050/081 053/082 054/081 054/080 054/078 054/075 053/073
22/T 13/T 25/T 35/T 46/T 47/T 46/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...None.
WY...None.
&&
$$
weather.gov/billings
Area Forecast Discussion
National Weather Service Dodge City KS
513 PM CDT Sun Jun 4 2023
...UPDATE TO AVIATION...
.SHORT TERM...(This evening through Monday night)
Issued at 1231 PM CDT Sun Jun 4 2023
1230 pm observations show upper level winds coming from the
southeast to the northwest as the major upper level influence is
coming from a large blocking high in the southern Canadian
prairies. A weak upper low continues to circulate in southeast
Colorado and an area of lift has led to a line of slow moving
storms from around Meade to the Texas panhandle. Expect scattered
storms through the afternoon to move from east to west. With
little vertical speed and directional shear severe weather is not
anticipated.
For tonight any storms that develop during the afternoon should
gradually fall apart from the loss of daytime heating that the
activity should rap up around midnight. With the dying storms a
meso high should develop in eastern Colorado and keep the surface
and boundary layer winds light and from the east. With the lack of
mixing and saturated ground we potentially could see the repeat
of some fog developing around sunrise. Lows should fall into the
upper 50s and lower 60s.
Monday should have similar conditions to Sunday with the exception
of a little more sun in the morning which should help to give us
slightly warmer afternoon temperatures. We should also have
another 700 mb shortwave retrograding from central Kansas to
western Kansas in the afternoon which could lead to more pop up
showers and storms. With the low confidence of just where this
lift sets up along with the already moist ground and good daytime
heating...decide to give all of the area at least 20% POPs as this
pattern could lead to rain just about anywhere. Highs should reach
into the lower 80s.
Monday night any storm develop should fall apart after sunset and
we should be left with partly cloudy skies and light winds. Lows
will be in the upper 50s to lower 60s.
.LONG TERM...(Tuesday through Sunday)
Issued at 221 PM CDT Sun Jun 4 2023
Key messages will be continued spotty chances of rain through the
middle of the week with increasing chances of rain towards the
weekend.
Upper level winds will be in an omega pattern through the mid week
with a strong upper high over the northern plains and a closed low
moving onshore in California aided by the subtropical jet giving
it some eastward momentum. Ahead of the low we will have a ridge
in Colorado and New Mexico. With the influence of the high the
upper level winds through the troposphere will continue to be
light so overall during the afternoon heating we could see some
pop up storms Tuesday through Thursday but with no real confidence
about where the lift will be having around 20% POPs should
suffice.
Towards the end of the week into the weekend the upper high should
weaken a bit and retrograde towards the Canadian rockies which
should allow the subtropical jet to increase into Texas and the
Gulf of Mexico region by Saturday. This will dampen the ridge in
the Rockies and the deterministic and ensemble models show the
central plains being in more of the trough region. This also
coincides with long term model output having increasing QPF output
for Saturday and Sunday with GFS and Euro ensembles showing
around 0.5 inch of rain. With the lack of strong upper level winds
through the weekend the severe risk should stay low outside of
possibly a wet microburst from a dying storm.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 512 PM CDT Sun Jun 4 2023
Despite a few passing showers through early evening, VFR conditions
are likely in vicinity of all TAF sites through early Monday. Light
and variable winds are expected during the period as a broad, but
weak surface high remains situated across the Great Lakes.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 57 81 58 82 / 30 20 20 10
GCK 55 79 56 80 / 30 20 20 0
EHA 56 75 55 78 / 50 20 20 10
LBL 57 79 56 80 / 40 20 20 10
HYS 59 83 59 85 / 10 20 20 10
P28 62 85 63 85 / 10 30 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Tatro
LONG TERM...Tatro
AVIATION...JJohnson
Area Forecast Discussion
National Weather Service Des Moines IA
703 PM CDT Sun Jun 4 2023
...Updated for the 00z Aviation Discussion...
.DISCUSSION.../Tonight through Sunday/
Issued at 201 PM CDT Sun Jun 4 2023
Key Messages:
-- Continued warm, humid, with afternoon isolated/scattered storms
today and Monday
-- Higher chances of storms with locally heavy rains Tuesday and
Wednesday
-- Transition mid to late week to cooler, but seasonal air with
anonymously low humidity for this time of year
Details: Overall upper level pattern remains in an omega block with
the mid-level ridge over the central part of the US into the central
Canadian provinces having moved a bit westward since this time
yesterday and the eastern North American trough. This has kept the
flow over Iowa from the east or northeast through the atmospheric
column and the few showers and storms this morning and this
afternoon`s activity has been dropping to the west or southwest.
Once again, forecast soundings show a dearth of deep layer shear,
which will result in pulsey type storms. While low level lapse rates
remain steep and may allow for small hail, the dry subcloud air
could result in sub-severe gusty winds given the potential of dry
air entrainment, which could speed up momentum transport to the
surface. 9z/12z RRFS and recent runs of the HRRR and NamNest show
gusts of 30 to 40 knots at most. The weak steering flow also means
locally heavy rainfall, but deterministic convective allowing models
(CAMs) and the 0z and 12z HREF show totals around or less than 2
inches so do not foresee any hydrology concerns outside of poor
drainage ponding. Additional storm development has also occurred
over eastern Iowa just east of the forecast area ahead of drier air
arriving from Illinois. As has been the case in past days, all of
this activity should dissipate into this evening.
Behind this moisture boundary, HRRR and RAP both indicate smoke will
be pushing west through western Illinois into eastern Iowa from
wildfires in the Quebec and Ontario provinces. Much of this will be
high-level smoke arriving tonight and being pushed southward through
the day Monday over eastern Iowa. There is more uncertainty on any
near-surface smoke due to model trends. The 12z HRRR had modest
concentrations making it as far west as a Waterloo to Newton to
Chariton line. However, hourly runs of the HRRR since and the 15z
RAP show lesser concentrations compared to the 12z HRRR. Thus, will
just opt for this mention and monitor trends east of the forecast
area this evening and overnight. As a general reminder, while we may
increase sky cover to account for high-level smoke and add haze or
smoke to the weather grid for surface impacts to visibility when
applicable, air quality monitoring and issuance of any air quality
advisories are the responsibility of our partners at the Iowa
Department of Natural Resources.
The rest of Monday will see little in the way of rainfall, though a
few storms are possible over northern Iowa as the cool front
approaches the area from the northeast. Higher and more widespread
chances are likely on Tuesday into Wednesday as this boundary looses
its momentum and slowly progresses through the state. This cool
front will finally be pushed west of the forecast area later
Wednesday as a lobe of vorticity drops around the west side of the
eastern US longwave trough. Severe weather is unlikely Tuesday and
Wednesday with less than 20 knots of deep layer shear, though
initial storms could pose a small hail and gusty wind risk for
reasons similar to what may occur today/Sunday. There may be a bit
more concern for locally heavy rainfall as moisture pools ahead of
the slow moving boundary with slow storm motions. Precipitable water
values are a bit higher than yesterday at this time above 1.5 and at
some times near 1.75" and warm cloud depths will be near 11500 feet.
While there is not much for CAM guidance at this time range, the
NamNest shows 1-2" totals in 3 hours. Seasonal temperatures, but low
humidity air will arrive later Wednesday and stay into Thursday as
surface high pressure spreads southward over the Great Lakes and
Ohio Valley and keeps the boundary west of the state. This high will
begin to depart the region on Friday allowing for warmer conditions
compared to Thursday. Our next rain and storm chances may come at
some point next weekend as a shortwave trough rotating around the
Hudson Bay low brings a front into the region.
&&
.AVIATION.../For the 00Z TAFS through 00Z Monday evening/
Issued at 701 PM CDT Sun Jun 4 2023
VFR conditions are generally prevailing across the TAF sites this
evening with mentions of scattered/broken VFR ceilings due to
ongoing convection. Scattered showers and thunderstorms may impact
KDSM and KFOD early in the TAF period leading to VCTS mentions
for these areas. Otherwise, expect VFR conditions to continue
throughout the period with few or scattered clouds with high
bases. Winds will generally be calm at all TAF sites late this
evening, with variable winds at KMCW. Smoke may be of concern for
KMCW Monday morning but have opted to not make mentions for this
TAF period.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION...Ansorge
AVIATION...Castillo/Curtis
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
955 PM CDT Sun Jun 4 2023
...New UPDATE...
.UPDATE...
Issued at 955 PM CDT Sun Jun 4 2023
The showers and thunderstorms from earlier today have dissipated.
However, expect some redevelopment as the evening into overnight
progress as a weak impulse moves over our area. Radar already shows
some over the Hill Country. The main threat will be locally heavy
rainfall with small hail and gusty winds also possible.
&&
.SHORT TERM...
(Tonight through Monday night)
Issued at 232 PM CDT Sun Jun 4 2023
There is a narrow band of elevated light rain showers moving into
the I35 corridor at the present time. Another area of more surface
based activity is developing along an old boundary west of San
Antonio where temperatures have warmed into the lower 80s. For the
remainder of the day expect the areas south of I-10 to initially
have the best chances for deeper convection. Things behind the
elevated showers near the I35 corridor to the west look stable on
satellite. Temperatures in the Hill Country remain in the lower to
middle 70s behind this with some high clouds continuing and this
should keep things fairly stable for at least a few more hours. Will
have to monitor things closely to see if there is any
destabilization there for more robust surface based convection.
Where temperatures are in the 80s, instability values will be high
enough to warrant a strong storm or two with perhaps some marginal
hail and wind gusts. A marginal risk for severe storms is in the
latest Day 1 outlook for much of the area. The other main hazard
with any stronger cell will be the threat for locally heavy rainfall
that could lead to minor flash flooding especially for areas that
received some prior heavy rainfall.
Think most of the activity today and this evening should primarily
be diurnally driven with most of the activity dying off by 9-10 pm.
Latest runs of the HRRR do show some redevelopment over portions of
the Hill Country after midnight with a weak impulse. Will show a 20
PoP there in the overnight period to account for that. Lows tonight
will be in the 60s with some lower 60s in the Hill Country.
Another round of scattered showers and thunderstorms can be expected
on Monday. Latest Day 2 outlook keeps us in general thunder. Locally
heavy rainfall will be the main threat tomorrow. Highs will be in
the 80s. Most locations will stay dry tomorrow night with lows back
in the 60s with some possible near 70 degree readings near the Rio
Grande.
&&
.LONG TERM...
(Tuesday through Sunday)
Issued at 232 PM CDT Sun Jun 4 2023
South-Central Texas will remain under a northwesterly flow aloft
with upper level ridging centered just to our west from Northern
Mexico into West Texas while broad troughing continues to focus
across the northern Gulf coast to the Northeast US. With not too
much change, the opportunity for scattered convection is again
expected from Tuesday afternoon into Tuesday evening where some
locally heavy rainfall may be possible. Activity likely is to
decrease through Tuesday night as majority of the model guidance
keeps the activity mainly diurnally driven. Afternoon highs on
Tuesday top out in the mid to upper 80s for most but some areas
along the Rio Grande may get into the low 90s. The overnight low
temperatures will otherwise bottom out in the mid to upper 60s
with again some low 70s possible near the Rio Grande.
The center of the ridge to our west nudges slowly eastward from
Wednesday through the upcoming weekend. This will lead into a
warming trend where slightly above average temperatures are to
develop from late week into the weekend. Peak heat index values
during the afternoons will climb to around or in excess of 100
degrees. While the convective chances and areal coverage should
reduce compared to the start of the week, near normal moisture
levels along with the continued presence of a northwest to west-
northwest flow aloft will still allow for at least some low end
opportunities of rain and storms to remain in the forecast. The
seabreeze along with outflow/activity coming from the Trans Pecos
would likely become the best triggers for any of these low end
probabilities.
&&
.AVIATION...
(00Z TAFS)
Issued at 646 PM CDT Sun Jun 4 2023
ISOLD TSRA from KUVA to KECU and from KPEZ to KCOT with ISOLD SHRA
and patchy RA elsewhere will gradually decrease, however some
activity will linger overnight into morning. Will maintain -RA at
KSAT/KSSF through 03Z. Expect activity to redevelop on Monday and
have maintained VCSH for the I-35 sites where the best chances will
be. Later forecasts may have update to go with prevailing based on
trends. VFR flying conditions will prevail tonight through Monday
evening. There are potentials for reductions in CIGs/VSBYs due to
saturated soils late tonight through mid morning and in SHRA/TSRA. A
weak surface pressure gradient will bring a mostly VRBL wind at 5 KTs
or less, however gusty winds are possible in and near any SHRA/TSRA.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 67 87 67 88 / 20 50 20 40
Austin Bergstrom Intl Airport 66 87 66 87 / 20 50 20 40
New Braunfels Muni Airport 66 86 66 86 / 20 40 20 40
Burnet Muni Airport 64 84 64 85 / 20 50 20 40
Del Rio Intl Airport 68 88 70 91 / 10 20 0 10
Georgetown Muni Airport 65 86 65 86 / 20 50 20 40
Hondo Muni Airport 65 85 66 87 / 20 30 10 30
San Marcos Muni Airport 65 85 65 86 / 20 50 20 40
La Grange - Fayette Regional 67 85 68 85 / 20 50 30 50
San Antonio Intl Airport 66 85 67 87 / 20 40 20 30
Stinson Muni Airport 67 85 67 88 / 20 30 20 30
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Short-Term...04
Long-Term...17
Aviation...04
Area Forecast Discussion
National Weather Service Grand Forks ND
1030 PM CDT Sun Jun 4 2023
.UPDATE...
Issued at 1022 PM CDT Sun Jun 4 2023
Increased temperatures slightly for tomorrow. Otherwise, the
shower and thunderstorm activity has diminished substantially
this evening, with the main area now located around Lake of the
Woods. Chances will continue to drop as we head into the overnight
hours. Tomorrow we will see further chances for showers and
storms in the afternoon and evening hours.
UPDATE Issued at 618 PM CDT Sun Jun 4 2023
Thunderstorm activity is slowly diminishing in coverage this
evening, but areas around Thief River Falls and the western
Devils Lake Basin continue to see higher chances. Locally heavy
rainfall, frequent lightning and thunder, and brief gusts up to
40mph are possible with some of these thunderstorms. Daytime
heating is driving these thunderstorms, so once that becomes lost
chances dwindle and showers remain. We continued the chances for
scattered thunderstorms through sunset. Further chances tomorrow
afternoon once again.
&&
.SHORT TERM...(This evening through Monday night)
Issued at 308 PM CDT Sun Jun 4 2023
Key Messages:
-Scattered thunderstorms will continue into the early evening, with
a few isolated strong to severe storms possible.
-Hot temperatures prevail today and into tomorrow.
-Another round of scattered thunderstorms is anticipated on Monday,
with coverage and severity being the primary uncertainties.
Discussion...
This afternoon, ridging aloft persists. However, convective
temperatures have been reached and scattered thunderstorms have
developed across much of the region. While any one storm is unlikely
to see strong to severe development, with a plethora of outflow
boundaries and storm scale kinematics at play, an isolated strong to
severe storm will still be possible this afternoon. Instability of
2000+ J/kg is being analyzed by latest RAP mesoanalysis, alongside
low level lapse rates pushing 9 C/km. While instability is highly
favorable for thunderstorm development, overall shear is lacking,
with negligible 0-3 and 0-6 km shear currently being analyzed. Storm
scale interactions may still be enough for isolated strong to severe
thunderstorms to develop though. While widespread severe weather is
not anticipated, any stronger storms that do develop will have the
potential for gusty winds over 40 mph, small hail, brief heavy
rainfall, and frequent lightning.
Furthermore, a weak backdoor front currently to the northeast of the
forecast area is expected to gradually drop southwestward through
the short term period. As this secondary foci for lift approaches,
scattered thunderstorms will continue to be possible over the
northern forecast area through the early evening. This will be the
likely area for strongest thunderstorm development outside of any
storm scale enhanced thunderstorms. Ensemble guidance continues to
hint at a rather progressive progression of the front. Latest RAP
guidance suggests that the front will be draped over the central
forecast area by mid morning Monday, pushing toward the border of
the Dakotas by mid to late afternoon. It should be noted that HREF
depicts a slower trend of the frontal passage though. Regardless, as
this front moves through the region, there will be some potential
for training showers and thunderstorms along the front. Any
deviation from the progressive nature would in turn yield a higher
chance for training to occur. Regardless, any flash flooding would
likely be tied to urban centers.
As the front moves through the region on Monday, there is some
potential to see a very slight downward trend in temperatures. Highs
in the 80s to low 90s are still expected. While the front will
provide the primary mechanism for thunderstorm development, as long
as temperatures rebound, another round of widely scattered
thunderstorms will be possible once convective temperatures are met
Monday afternoon.
.LONG TERM...(Tuesday through Sunday)
Issued at 308 PM CDT Sun Jun 4 2023
Key Messages:
-Warm, above normal temperatures persist through at least the week
ahead, with a potential cool down to near normal by the weekend.
-Chances for showers and storms will be possible each afternoon.
-Near critical fire weather conditions possible late week into the
weekend.
Discussion...
The overall pattern aloft looks to remain somewhat stagnant through
the majority of the week ahead. As a large scale blocking pattern
remains in place, upper level ridging over the northern Plains looks
to be a mainstay. Latest cluster analysis indicates that some
weakening of the ridge will occur toward the middle and latter
portions of the week, before it begins to retrograde westward,
introducing northwesterly flow aloft to the region. This overall
pattern shift will be dictated by a strengthening trough over the
eastern CONUS, meaning that its positioning will be paramount in the
upper level pattern evolution through the long term period.
Prior to the pattern shift though, the weather across much of the
week ahead will look to remain status quo. With weak, but persistent
south-southeasterly flow at the surface, WAA will continue to feed
above normal temperatures and moist air to the region. While the
ridge aloft looks to remain centered over the forecast area,
providing large scale subsidence aloft and a lack of appreciable
shear, afternoon temperatures look to climb into the 80s to low 90s
each afternoon. With convective temperatures generally running in
the mid 80s, diurnal convection is expected each afternoon across a
majority of the CWA. Despite the likely presence of moderate
instability (1000-2000 J/kg), shear will be lacking underneath the
ridge. As a result, widespread organized severe weather is not
anticipated. That being said, a few isolated strong to severe storms
will be possible given any storm scale modifications of the
environment.
As mentioned prior, there is some variability regarding the timing
of northwesterly flow aloft returning to the region. Most ensemble
guidance indicates this pattern shift moving toward the weekend
though. Given the amplified nature of the ridge and the overall
positioning of the northwesterly flow favoring a trajectory toward
the Great Lakes, a brief reprieve from scattered showers and
thunderstorms may be possible across the weekend period. That being
said, any shift in the flow pattern could result in a shortwave
impacting the region and bringing with increasing rain chances.
Cooler temperatures will also be possible around this time frame as
well, with a return to near normal high temperatures in the upper
70s to low 80s anticipated. Accompanying this cool down and
northwesterly flow aloft will be an overall drier air mass.
Minimum RH values dropping into the low 30s look to be accompanied
by at least sustained southeasterly winds, which, depending upon
the condition of fuels, may lead to near critical fire weather
conditions, namely across northwestern and west central Minnesota
that may need to be monitored moving forward.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1022 PM CDT Sun Jun 4 2023
Shower and thunderstorm activity continues to diminish as
instability is lost across the region. Some isolated VCTS is still
possible in TVF through 08z, otherwise just -SHRA. GFK could see
some brief showers through 08z as well. Other areas conditions are
turning dry with light and variable winds.
We should start to see winds turn toward the east around 15-18z,
but remain around 5-10kts sustained. Further chances for showers
and thunderstorms tomorrow afternoon and evening for all
sites. Coverage of showers and storms will be scattered at best.
Otherwise, cloud decks will turn BKN during this time. Some of the
storms could bring gusty winds creating erratic wind changes at
times near and around storms.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...Spender
SHORT TERM...Rick
LONG TERM...Rick
AVIATION...Spender
Area Forecast Discussion
National Weather Service Grand Rapids MI
903 PM EDT Sun Jun 4 2023
LATEST UPDATE...
Update
.UPDATE...
Issued at 901 PM EDT Sun Jun 4 2023
The humidity levels have risen 5 to 10 percent at most locations
early this evening. The winds have decreased as well. As the
temperatures slowly cool off, we will continue to see the humidity
levels rising. Thus we allowed the Red Flag Warning to expire at 9
pm.
&&
.SHORT TERM...(This evening through Monday night)
Issued at 258 PM EDT Sun Jun 4 2023
The respite from smoke will come to an end later this evening as
another plume from the Quebec fires is entering eastern Michigan
and will drift west. A portion of this mid-level smoke could mix
down to the surface in pockets over mid Michigan prior to sunset,
and drift westward overnight. Air quality may be reduced from good
to moderate for fine particulates (PM 2.5) where this occurs. The
HRRR and RAP have also been suggesting more smoke mixing down
from late Monday morning and staying through the rest of the day
across much of our area. The concentrations of smoke modeled by
the HRRR for Monday imply a haze of reduced visibility (generally
in the range of 4 to 7 miles) and air quality potentially becoming
unhealthy for sensitive groups, as experienced in Wisconsin and
the UP today.
Fire danger remains very high for June. More information in the
Fire Weather section.
Patches of high- to mid-level clouds are expected to move in from
the north late tonight into Monday ahead of a very weak (and dry)
surface cold front, with winds turning more northerly behind it.
Some sprinkles can`t be ruled out Monday morning in the north.
.LONG TERM...(Tuesday through Sunday)
Issued at 328 PM EDT Sun Jun 4 2023
Some very much needed rain could be happening on Saturday into
Sunday as there is good model agreement that showers and embedded
thunder will accompany a cold front passage. The overall blocky
pattern that has persisted and brought the very low humidity and
lack of rain does not appear to be breaking down, but the pattern
retrogrades a bit with the central Great Lakes on the western
periphery of an upper low with a shortwave trough rotating through
by the end of the week.
Surface dew points are still forecast to be in the upper 40s to
lower 50s, but there is enough mid and upper level moisture
pooling ahead of the cold front to produce precipitable water
values of about 1.25 inches, along with the potential for elevated
instability, which possibly could be surface-based on Sunday
afternoon.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 737 PM EDT Sun Jun 4 2023
The main impact to aviators will be the smoke thats around and the
reduced visibilities that are forecast. Model guidance suggests
the smoke seen on satellite imagery over Lake Huron will build
down into the TAF sites causing the visibilities to lower. As a
result we will continue to feature this trend in the forecast. A
wind shift is forecast to occur on Monday that may shift the smoke
away from the TAF sites. Mid to upper level clouds will spread in
but given the dry low level conditions, bases are still projected
to remain well into the VFR category.
&&
.MARINE...
Issued at 328 PM EDT Sun Jun 4 2023
Webcams still showing no wave action close to shore this afternoon
as offshore winds continue. Waves around 2 feet can be expected
further offshore as currently observed at the mid-lake buoy.
Looking further ahead, we will have to watch for a push of
northwest to north winds beginning Monday night and lasting
through Thursday. This could cause some choppy water, especially
around Big and Little Sable Points.
Upwelling from the offshore winds has dropped the water
temperatures at the beaches into the 40s today, and not much of a
rebound is expected in the northerly flow through this week.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...None.
&&
$$
UPDATE...MJS
SHORT TERM...CAS
LONG TERM...Ostuno
AVIATION...MJS
MARINE...Ostuno
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1022 PM EDT Sun Jun 4 2023
.SYNOPSIS...
Another cold front will slowly drop southward into our region
through mid week providing more of a focus for afternoon and evening
showers and storms. Temperatures will warm to above normal on
Tuesday and Wednesday ahead of the front and cooler on Thursday to
the north of the front.
&&
.NEAR TERM /THROUGH MONDAY/...
As of 1011 PM EDT Sunday: The latest satellite imagery depicts
generally clear skies outside the NC mountains, which retain a
smattering of convective debris from activity across the Smokies
earlier this evening. That activity has largely vanished, however.
At this point, the 850mb chart still depicts weakly E winds.
CAMs indicate that a switch to WSW winds is imminent, but the
new 00z HRRR no longer depicts any secondary vort lobe during
the overnight hours...and as a result mountain sprinkles look
increasingly minimal. Left some chance PoPs in the grids for the
next few hours, just in case.
Guidance continues to double down in depicting either fog or
low stratus during the predawn hours. Indeed, a quick look at
crossover temps this evening indicates we may see lows a solid
2-3 degrees below thresholds for fog/stratus formation...with at
least some evidence from the GFS and RAP favoring fog over low
stratus in many areas. Lows tonight will be a few degrees above
climo across the western half of the CWA and a few degrees below
climo across the eastern half of the CWA.
Sfc high pressure will gradually weaken over the region through
Monday. With NW downsloping flow in place, we should see warmer
high temps return. Highs should be a few degrees below climo along
the I-77 Corridor and near climo to a few degrees above climo
elsewhere. Another round of diurnal showers and thunderstorms
will develop Monday afternoon and evening ahead of an approaching
mid-level shortwave...though initiation looks a bit delayed by the
lack of any synoptic forcing and the presence of a weak capping
inversion during the early afternoon hours. The SPC Day 2 Severe
Wx Outlook has a Marginal Risk for severe wx mainly east of the NC
mtns Monday afternoon and evening...which seems reasonable given
that CAMs show SBCAPE values ranging from 1000-2000 J/kg beneath a
500mb speed max providing as much as 30-35kts of 0-3km bulk shear
by 00z. The main potential impacts look to be damaging winds and
large hail; the CAMs are in reasonable agreement on initiation of
discrete cells over the NC escarpment zones, translating into the
Piedmont and Upstate through late evening. There`s even decent
support for some rotating updrafts, but the lack of more pronounced
low-level shear as well as the presence of generally high-DCAPE
air across the CWA will severely limit tornado potential. The 00z
HREF, which knows I`m eagerly waiting for it and is thus taking
its time to make me sweat, will be enlightening. With PWATs a
little on the low side, and better storm motion during the peak
of the event tomorrow, heavy rain looks to be a lesser concern
than the severe risk, especially with the HREF PPM only producing
bullseyes of 1-1.5" against a 3h FFG of ~3".
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 234 PM Sunday: We may yet be dealing with ongoing
thunderstorms across the Piedmont of the Carolinas and Georgia
on Monday evening, if some of the convection-allowing models are
correct. The forecast will be changed to hold onto a chance of
showers and storms after 00Z Tuesday accordingly, but still think
that this activity will move off to the southeast and diminish
by late evening as we diurnally stabilize. The weak sfc boundary
responsible in part for the convection has been poorly handled
by the guidance the last few days. The boundary is now thought
to drop into the region Monday night and could be draped across
the fcst area for Tuesday. Guidance agrees. The persistent omega
blocking pattern supports this scenario, with the cyclonic flow
aloft helping to bring this boundary down from the north. If
this is the case, the air mass south of the boundary would have
sufficient sfc-based CAPE of 1500-2000 J/kg and shear around 20
kt to make for some interesting storm potential. Precip probs were
raised into the chance range across the srn half of the fcst area
to account for this. Temps will rebound some more, perhaps up to
a category above normal, which will help us realize the better
instability along and south of the boundary in the afternoon. The
boundary, such that it is, should sink southward in the evening
and any deep convection should diminish quickly with the loss of
heating. Tuesday night should be quiet.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
As of 137 PM Sunday: The omega blocking pattern still looks like it
will persist at least through Friday, but possibly right through
the weekend, even though some of the guidance shows a shift that
would bring us at least briefly into a warmer and more convective
part of the pattern at the end of the period. The 12Z model runs
show a stronger and more vigorous wave rotating around the western
side of the upper low over New England on Wednesday and Wednesday
night, which would ultimately bring better mid/upper forcing to
bear across our region on Thursday. This short wave would drive
a stronger backdoor front southward across the fcst area that
would better-organize showers and storms over a larger area,
necessitating a chance of showers and storms across the entire
forecast area Wednesday night and Thursday. Guidance is supportive
of a likely precip prob with this passage over at least parts
of the fcst area, but we will limit the precip to the chance
range for now. The threat for severe storms on Thursday appears
to be low as the air mass fails to recover ahead of this front,
leaving very little buoyancy available. The arrival and passage
of this boundary will knock about ten degrees off high temps from
Wednesday to Thursday, but temps will start to rebound on Friday as
high pressure builds in from the northwest. Saturday looks quiet
with sfc high pressure moving in and our flow aloft flattening
out as the eastern upper low gets kicked out to the east by the
next nrn stream short wave. Unfortunately, this wave might cut
off into a new eastern upper low by late Sunday, re-establishing
the omega block for the first part of the next week. The good
news for the time being is that most of next weekend looks fair
with low precip probs and temps warming back to normal Saturday,
then a bit above normal for Sunday.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
At KCLT and elsewhere: Finally seeing MVFR ceilings along the
I-77 corridor begin to give way, heralding their breakup in
the immediate future. Elsewhere, generally VFR conditions,
though with some MVFR-level non-cigs lingering in the mountains.
Although convection continues in the SW NC mountains, this is
expected to remain confined to these remote zones, with little
impact on any of the terminals. Overnight, the non-mountain zones
are expected to remain VFR, with MVFR restrictions developing across
the NC mountains after midnight. Left in mention of VCSH at KAVL
overnight, as guidance continues to support a round of weak showers
developing over the mountains after midnight. By daybreak, KAVL may
see MVFR to IFR fog and low stratus, especially if it takes a direct
hit from a shower earlier in the night. These restrictions should
clear up quickly after daybreak. Thereafter, expect a SCT/BKN cu
field to develop through the day as a front sags south out of the
Cumberland Plateau, and decent instability ramps up across much of
the forecast area. By evening, convective initiation is expected
across the mountains, and these storms will gradually propagate
south and east into the Piedmont/Upstate zones; all terminals now
carry PROB30s for TSRA and associated restrictions. Confidence
on timing is moderate at best, at this point, but confidence in
scattered thunder at some point during the evening/early overnight
is high.
Outlook: Another cold front will arrive from the north by the
middle of the week, bringing increased shower and thunderstorm
chances along with associated restrictions.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
SYNOPSIS...DEO
NEAR TERM...AR/MPR
SHORT TERM...PM
LONG TERM...PM
AVIATION...MPR
Area Forecast Discussion
National Weather Service Houston/Galveston TX
609 PM CDT Sun Jun 4 2023
...New AVIATION...
.SHORT TERM...
(This evening through Monday Night)
Issued at 209 PM CDT Sun Jun 4 2023
Looking at water vapor imagery and the RAP 500MB analysis, one
sees a mid/upper pattern featuring modest ridging over the Four
Corners region while troughing dominates over the U.S. southeast
resulting in a NW mid/upper flow pattern over central and southern
Texas. However, a more subtle mid/upper trough over eastern Texas
is keeping the mid/upper flow quite light and somewhat variable.
This results in a complex convective outlook across the FA.
Current guidance along with the current synoptic set up support a
more diurnally force convective situation today leading to the
development of isolated to scattered showers and thunderstorms
this afternoon before things quiet down overnight. But the
presence of the nearby UL/ML NW flow pattern does provide an
opportunity for overnight convective development, especially if
this NW flow can nudge a little farther north over our CWA. Due to
the NW flow`s farther south orientation, we tend to lean towards
the diurnally forced scenario with PoPs highest later this
afternoon and into the early evening (~30-40 percent for most
areas). However, we did want to give some weight to the
alternative by having slight (~20-25 percent) PoPs CWA wide into
the overnight hours.
So long as we don`t experience another mesoscale surprise like
last night, Monday should feature a high chance of showers and
thunderstorms as a slightly more robust shortwave feature,
currently over NW TX, works its way down into southeastern /
coastal Texas. PoPs generally range 50-70 percent tomorrow.
Locally heavy rainfall will be the primary concern. However, we
cannot rule out an isolated stronger thunderstorm or two. General
rainfall amounts are expected to be manageable.
Regarding temperatures, we have been gradually lowering our
forecast high temps for this afternoon. Some locations remain as
cool as the upper 70s as I type this AFD. However, it will not
take much June sunshine to boost temperatures at least into the
mid if not upper 80s. But some locations could struggle to warm
past the low 80s if cloud cover remains resilient. More clouds and
a cooler lower atmosphere would also tend to inhibit convection.
Lows tonight appear seasonal in the upper 60s to low 70s.
Tomorrow`s highs are expected to be in the mid/upper 80s.
Self
&&
.LONG TERM...
(Tuesday through next Saturday)
Issued at 209 PM CDT Sun Jun 4 2023
The rather unsettled pattern that we start the week with will
hold through midweek with a low amplitude trough persisting over
the region. Global models do settle into more of a diurnal
convective pattern, although timing of wetter periods will remain
quite uncertain under weak nw flow aloft. That being said, NBM is
pretty aggressive with PoPs on Tuesday along residual surface
boundaries/sea breeze. There is no good reason to differ at this
point as combination of diurnal heating and weak lifting from
passing shortwave should make for a convectively active day. This
general unsettled pattern should hold into Wednesday, but by
Thursday and into the weekend shortwave ridging begins to take
root aloft. This will bring much lower PoPs and higher temps to
end the week. We should begin to see triple digit Apparent Temps
by Friday into next weekend.
Temps will likely remain below normal a bit due to the wetter
pattern to start the period, but should be near to slightly above
normal by the end of the week as we settle into more summer-like
weather for next weekend.
Evans
&&
.AVIATION...
(00Z TAF Issuance)
Issued at 604 PM CDT Sun Jun 4 2023
Some afternoon pop-up thunderstorms near CLL will dissipate within
the next hour with the loss of daytime heating. Otherwise, light
winds and VFR conditions will prevail through tonight. Expecting
higher coverage of thunderstorms across the region tomorrow
beginning around noon (maybe earlier at the immediate coast) that
will pulse up and down through the evening hours. Exactly where is
unknown at this time, so went with VCTS for most of the
terminals. Where the thunderstorms do form, gusty variable winds
and lowered visibilities due to rain is expected.
Fowler
&&
.MARINE...
Issued at 209 PM CDT Sun Jun 4 2023
Scattered showers and thunderstorms should slowly wane this evening
over the outer waters. In general, expect a slow moving upper level
low to bring continued unsettled weather the next few days. Outside
of any showers or thunderstorms, light winds and low seas should
persist.
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 68 86 67 85 / 30 60 20 40
Houston (IAH) 70 87 70 85 / 30 60 30 60
Galveston (GLS) 75 85 75 84 / 30 50 40 50
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
SHORT TERM...Self
LONG TERM....Evans
AVIATION...Fowler
MARINE...Evans
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
819 PM CDT Sun Jun 4 2023
.SYNOPSIS...
Issued at 818 PM CDT Sun Jun 4 2023
Smoke from wildfires in Quebec will continue to degrade air quality
and result in hazy skies through at least Monday. Otherwise, it`ll
be warm and dry to kick off the work week, with chances for
precipitation arriving late Tuesday into Wednesday with a back door
cold front. Higher precipitation probabilities will arrive this
weekend as a trough digs into the Great Lakes.
&&
.UPDATE...
Issued at 818 PM CDT Sun Jun 4 2023
Dry conditions will prevail the remainder of the night as daytime
instability wanes with sunset and showers and storms off to our
west begin to diminish. Temperatures are on track to fall into the
50s overnight under mostly clear but hazy skies.
Deubelbeiss
&&
.DISCUSSION...
Issued at 229 PM CDT Sun Jun 4 2023
<<<<<<< Key Messages >>>>>>>
1. Smoke-driven air quality concerns through at least Monday
2. Temperatures trending less warm
3. Chance for showers Tuesday-Wednesday
Better opportunity this weekend
Lest anyone beguile you into believing the atmosphere is not a
dynamic fluid, take a look at water vapor satellite imagery, which
reveals east-southeast flow overspreading central Illinois on the
west side of high pressure centered across southern Lower
Michigan/northern Indiana. Visible satellite shows lofted wildfire
smoke continues to flow into our area from the east. Fortunately,
the highest particulate concentrations are aloft, though (1)
visibility reductions at multiple observing sites and (2) PM2.5
particulate concentrations in the unhealthy category for sensitive
groups from Illinois EPA both confirm some of this is near the sfc,
where HRRR and RAP smoke suggest concentrations will increase this
evening as the atmosphere decouples and particulates become trapped
beneath the near sfc inversion. (PM2.5 are inhalable particulates
that are less then 2.5um -- for perspective, a strand of human hair
is ~70 um -- in diameter and in this case are emanating from
wildfire smoke.) HRRR suggests an even more significant increase in
near sfc smoke concentration tomorrow morning east of I-57, but
since the wildfires responsible are way up in Quebec this trajectory
is not going to be perfect. The greatest concern with this would be
air quality deterioration (southern Wisconsin and northeast Illinois
have experienced unhealthy -- and not just for sensitive groups --
air quality much of the day already), the latest information for
which you can find at airnow.gov. The smoke, however, may also lower
temperatures tomorrow, as these particulates generally mitigate
receipt of shortwave (solar) radiation but remain largely
transparent to longwave (from earth`s sfc) radiation. It takes quite
a robust concentration to have this effect, though; our highs may
ultimately be just a degree or two cooler than NBM`s deterministic
forecast which has been doing well the past several days.
Otherwise, it`ll be pleasant and less warm with highs in the low to
mid 80s through midweek -- possibly (~30% chance, per NBM) even in
the 70s on Wednesday and/or Thursday in our northeast when >60% of
the LREF brings 850mb temps to sub 12 degC on the western edge of
the expanding upper trough centered across the northeast CONUS. When
the backdoor cold front with this system arrives late Tuesday-
Wednesday, it`ll bring some chance for showers and perhaps even
thunderstorms as a layer of elevated moisture and instability
arrives from the west-northwest. NBM now has 20-30% PoPs during this
time frame (highest in the southwest), which may need to be adjusted
up further eventually given ~40% of the LREF (CMCE+GEFS+EPS) now has
measurable precip falling across central Illinois.
Cluster analysis suggests agreement among the long range guidance in
north to northwest 500mb flow continuing through the weekend, with
varying degrees of sub-normal 500mb heights over Illinois across
individual clusters -- anywhere from 25-50m below climatological
normal in the least troughy cluster (dominated by the GEFS) to 100-
150m below normal in the troughiest two clusters (dominated by the
CMCE). The raw ensemble would suggest a 60-80% chance for measurable
precip this weekend, while the calibrated and bias-corrected NBM is
a little more pessimistic with only 50-60% PoPs by late Saturday.
NBM does suggest, however, that there is a 35-50% chance for more
than 0.5 inches of rain by the time the upcoming weekend is through,
implying that this precip, being convectively-driven, could be quite
heavy -- at least in spots. Nonetheless, the chances appear quite
low (<10%) that we`ll receive enough to climb out of our precip
deficit, which at this point is 2 to 4 inches!
Bumgardner
&&
.AVIATION... (For the 00z TAFs through 00z Monday Evening)
Issued at 628 PM CDT Sun Jun 4 2023
High pressure will remain anchored over the Great Lakes providing
light NE flow and primarily VFR conditions through the period.
Some smoke from Canadian wildfires may occasionally drop vsby to
MVFR this evening and during the day Monday.
Deubelbeiss
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Indianapolis IN
934 PM EDT Sun Jun 4 2023
.Forecast Update...
Issued at 933 PM EDT Sun Jun 4 2023
No major changes needed to the ongoing forecast for tonight with
conditions generally evolving as expected. RH values are still in
the low 30 percent range across much of central Indiana but those
should gradually come up with the overnight cooling. Lows in the
low to mid 50s still look reasonable with the light winds and dry
airmass in place.
&&
.Short Term...(Through Monday)
Issued at 117 PM EDT Sun Jun 4 2023
A quiescent synoptic pattern continues across much of the country
with substantial positive midlevel height anomalies across Canada
and the northern tier, and negative height anomalies generally south
of about the 35th parallel. This is promoting weak flow aloft across
much of the country and no systems with substantial ageostrophic
motions to cause organized precipitation. One weak shortwave
perturbation peripheral to the large ridge positioned just west of
us has helped nudge a drier slightly cooler air mass into Indiana
while shifting +2-m temperature anomalies further westward.
Tomorrow, the brief reprieve from the above normal temperatures and
a dry continental air mass will both still be in place. A period of
mid-upper clouds may accompany another weak transient perturbation,
but dry air mass will preclude precipitation. This could limit
mixing depth and temperatures slightly, but RH will still be low,
and winds may again be around 10-15 mph during the peak mixing
period. So, elevated fire weather conditions may again occur.
Marginal wind speeds, green fine fuels (non-dormant), and still
relatively high 10-hour fuel moisture will all be limiting factors
for a more substantial fire weather concern.
Smoke from Quebec wildfires has favorable trajectories to move over
Indiana. Some of the lower layer depictions in the HRRR smoke model
show a signal, but regional and upstream observations show no
visibility issues and impacts in lower troposphere should be
minimal. It may occasionally look like (or enhance the appearance
of) thick cirrus, and augment light scatter where the red end of
the spectrum shows more at sunrise and sunset, but otherwise
impacts are not expected.
&&
.Long Term...(Monday night through Sunday)
Issued at 117 PM EDT Sun Jun 4 2023
The long range will be characterized by a broad and amplifying
trough over the northeastern United States. Lobes of vorticity are
modeled to occasionally rotate around the main trough axis and
through our region. Given the lack of moisture in the column, as
winds generally retain a northerly component, little in the way of
precipitation is expected.
Each lobe or shortwave trough may allow for reinforcing shots of
cooler drier air, with cloud cover and perhaps a few isolated
showers in the immediate frontal environment. The first of these
will arrive on Tuesday, likely from the north-northeast. This
`backdoor cold front` is expected to bring the coolest air of the
week. Temperatures at 850mb drop from around 15C today to 5-10C by
Tuesday evening. Corresponding surface temps drop from the mid 80s
Mon and Tue to upper 70s Wed and Thur.
As the first lobe of the trough fades away, another may drop from
the south by next weekend. Temperatures may gradually recover a bit
by Friday into the mid 80s, but another dry front from the north may
bump us back down into the upper 70s very late in the long range.
Model agreement fades rapidly by this point, however, so confidence
is a bit lower. Nevertheless, an amplified `blocky` pattern is
likely to persist through the period.
To summarize, expect near to slightly above normal temperatures with
below-normal precipitation. Additionally, wildfires burning
throughout the Canadian Province of Quebec may send periods of smoke
our way. Any impacts from smoke should remain relegated to the mid-
levels, with hazy skies and potentially vibrant sunrises / sunsets.
High temperatures may be suppressed if the smoke layer is thick
enough.
&&
.Aviation...(00Z TAF Issuance)
Issued at 651 PM EDT Sun Jun 4 2023
Impacts:
-None
Discussion:
VFR conditions expected through the TAF period with mostly clear
skies and northeasterly winds of 5-10kts. Smoke from wildfires will
lead to some opaqueness to the sky at high levels with otherwise
mostly clear skies.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Update...White
Short Term...BRB
Long Term...Eckhoff
Aviation...White
Area Forecast Discussion
National Weather Service Louisville KY
740 PM EDT Sun Jun 4 2023
...Updated Aviation Discussion...
.Short Term...(This evening through Monday)
Issued at 306 PM EDT Sun Jun 4 2023
Key Messages:
- Medium to high confidence in near-surface smoke concentrations
Monday afternoon.
- Dry and warm conditions continue.
Synopsis...Mid-level disturbance/vorticity has moved out to the west-
southwest per the SPC mesoanalysis with plenty of subsidence and
slow dry-air advection in its wake as noted in VIS satellite and
surface observations, respectively. In addition, convective
inhibition might be reinforced by plume of Canadian wildfire smoke
moving through southern Indiana as of this afternoon. The next 24-36
hours will feature stable and dry conditions with a back-door cold
front approaching the area from the north.
This Afternoon...Although a spotty shower and/or storm might not be
out of question the rest of the afternoon along the TN border,
current observations and model trends reflect mostly dry conditions
for the forecast area. Accordingly, have reduced PoPs with respect
to previous forecast, but still left a 10-20 chance in the official
grids. Furthermore, the smoke plume will remain rooted aloft without
any surface impacts for the moment.
Tonight...Surface winds will turn light and variable as the capping
inversion strengthens with slow southward advection of the dry
airmass give flow in the 850-700 mb layer. Smoke plume will slowly
move southward, as well, to account for hazy skies in south-central
KY tomorrow morning. The HREF guidance was hinting at patchy fog
before sunrise; however, this possibility has been reduced since the
area has remained rain-free. Still, fog could be limited to the more
protected valley areas.
Tomorrow...There are two changes with respect to the previous
forecast reasoning. The first one is the elimination of any PoPs for
Monday afternoon as the presence of dry air and the timing of the
cold front will spark convection south of the forecast area. The
second one is the presence of near-surface smoke as indicated by
HRRR guidance. As a result of surface concentrations of smoke
particles, the HREFv3 model suite has started to reflect reduced
visibilities for Monday afternoon along the westernmost counties.
The latter supports the inclusion of smoke in the official forecast
and issuance of another Air Quality Alert as health concerns arise
for sensitive groups.
.Long Term...(Monday night through Sunday)
Issued at 255 PM EDT Sun Jun 4 2023
The omega blocking pattern, featuring the continued upper ridge axis
across the central CONUS with flanking troughs along both the east
and west coasts with a persistent upper low over New England and one
over SoCal will remain predominant through the week. North to
northeasterly flow will continue over the Ohio Valley and smoke
associated from the Canadian wildfires over Quebec will increase in
density per the HRRR vertical integrated smoke Monday night into
Tuesday morning. Wouldn`t rule out periods of smokey haze through at
least the first half of the week given the overall upper air flow.
Embedded spoke of shortwave energy will pinwheel around the New
England closed low and work through the Ohio Valley Wednesday into
Thursday. This will help to push a backdoor cold front into
southern IN/central KY late Wed sparking a couple of scattered
showers/storms for Midweek. Behind the passing boundary, drier and
cooler air will advect in from the north.northeast as a sfc high
drops south out of the Great Lakes and into the Ohio Valley by the
end of the week. Temperatures will drop from the mid/up 80s on
Tues to the upper 70s and near 80 through the second half of the
week.
By the weekend, the closed New England upper low will start to shift
off to the east along with sfc high. Temperatures will warm back
into the mid 80s by Saturday and Sunday. Our best chance for
shower/storms looks to arrive by the end of extended as an upper
trough work southeastward from the Upper Midwest bringing a surface
cold front towards the area Sunday into Monday. Overall, there seems
to be pretty strong agreement in the deterministic models of the
overall pattern through the week and into the weekend and confidence
in the forecast remain medium to high.
&&
.Aviation...(00Z TAF Issuance)
Issued at 740 PM EDT Sun Jun 4 2023
VFR conditions continue to prevail during this TAF period. Winds
will be light and variable overnight. Dry weather will continue for
Monday with winds generally out of the northeast with speeds between
5-10 kts. Expect to see some mid-upper clouds and haze/smoke through
the period in association with the Canadian wildfires.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&
$$
Short Term...ALL
Long Term...BTN
Aviation...JML
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
617 PM CDT Sun Jun 4 2023
.SHORT TERM... (Through Late Monday Night)
Issued at 219 PM CDT Sun Jun 4 2023
Scattered showers and thunderstorms that developed earlier over
Illinois have dissipated. Now waiting on additional development in
advance of westward moving vorticity lobe that is now over the
eastern CWA. MLCAPES have increased into the 1000-2000+ J/kg range
along and west of the Mississippi River. These storms should
continue through sundown with the loss of daytime heating. With
mixing up to 750 mb today, couldn`t rule out some non-severe wind
gusts along with some brief downpours. Then mainly dry weather is
expected tonight into Monday as the upper ridge builds back into the
region.
Smoke from the wildfires over eastern Canada is showing up over the
Great Lakes and northern Illinois and Indiana. RAP and HRRR smoke
forecasts have it moving southeast, so have increased cloud cover
over the area tonight into Monday night. Near surface smoke
forecasts from these models suggest that the smoke may be over or
just east of the the eastern CWA, so will need to monitor this trend.
Temperatures today have been slightly cooler than yesterday thanks
to the high clouds. Lows and highs the next 36 hours should be
slightly cooler as slightly cooler air advects in from the northeast.
Britt
.LONG TERM... (Tuesday through Next Sunday)
Issued at 219 PM CDT Sun Jun 4 2023
Latest ensemble mean guidance continues to show that an upper high
will linger over the northern high Plains through the extended
period. Meanwhile a sharp trough will move south through the Great
Lakes and Midwest around a deep low over the northeast on Wednesday
while a second trough will drop down into the western Great Lakes
next weekend. At the surface, the winds will become weaker ahead of
the attendant front that will move southeast across the area Tuesday
night into Wednesday. Ensemble probabilities are now showing better
chances for measurable rain with the passage of the front Tuesday
night into Wednesday. Then mainly dry weather is expected
Thursday and Friday as high pressure drops southeast out of Canada
through the Midwest. There continues to be model differences next
weekend with a front that moves southeast across the area with
the aforementioned upper trough. This front will bring another
chance of showers and thunderstorms, but a number of the ensemble
members have no measurable rain next weekend.
Temperatures Wednesday into Friday will fall back closer to near
normal behind the front with 850mb temperatures closer to 10C.
Temperatures by next weekend become more unclear, but with 850mb
temperatures climbing back to near 15C and surface winds turning
out of the southwest ahead of the front, temperatures will be more
likely to climb back above normal.
Britt
&&
.AVIATION... (For the 00z TAFs through 00z Monday Evening)
Issued at 615 PM CDT Sun Jun 4 2023
Mainly dry and VFR conditions are expected through the period.
Only exception will be at UIN, COU, and JEF where I have included
VCSH or VCTS through 01Z to account for nearby showers and
thunderstorms which may affect the terminals. Winds will remain
light out of the east to northeast.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Marquette MI
640 PM EDT Sun Jun 4 2023
.SHORT TERM...(The rest of this afternoon and tonight)
Issued at 245 PM EDT SUN JUN 4 2023
...Dry and smoky this afternoon, cold front moves through tonight...
The GOES-16 Day Cloud Phase Distinction RGB shows sunny skies across
the area this afternoon, save for some diurnal cu developing over
the west and haze/smoke from the Quebec wildfires across the region.
With mid-level high pressure continuing to retrograde to the west
this afternoon, expect the smoke to linger over the area until at
least the overnight hours. Therefore, an Air Quality Alert is in
effect for all of the U.P. the rest of this afternoon through
tonight, as fine smoke particulates have made the air unhealthy for
people to be out in. Therefore, avoid outdoor activities today as
much as possible. With drier conditions over us today due to the
retrograding high pressure, RHs over the central and east have
already gotten into the 20 percents in the interior central and east
in spots. With temps close to the max already (2PM EDT), expect the
RHs to remain around the same this afternoon across the area save
for possibly dropping down near the Lake MI lakeshore late. Speaking
of temps, due to the smoke and ever-so-slightly cooler temps aloft,
maxTs aren`t expected to get as warm today as they were yesterday.
While temps in the interior west have already spiked into the mid
80s, expect the highs to be mainly in the low 80s in the interior
areas elsewhere and 70s near the Great Lakes.
Moving into tonight, expect a cold front dropping south from Ontario
to bring some cloud cover and possibly a few light rain showers with
a rumble of thunder or two. While the forcing is there for precip,
with only a couple hundred J/kg of CAPE to work with at most and
very dry air remaining in the lowest levels of the atmosphere,
expect only a light amount of rainfall in spots tonight; here`s to
hoping the HRRR is right about tonight, as that gives us the most
rainfall equitably across the U.P. While the light rain may
alleviate the smoke concerns over us, how much of a help it will be
continues to be a mystery; we won`t know until after the front moves
through. Expect the rainfall to end Monday morning. Some fog may be
possible behind the cold front over the Keweenaw and near Lake
Superior tonight, but I`m a little iffy about the chances given that
the airmass behind the cold front is very dry. With cloud cover over
the area tonight, expect the lows to be limited to mainly the 50s,
with the coolest temps expected right around dawn Monday.
.LONG TERM...(Monday night through Sunday)
Issued at 348 PM EDT SUN JUN 4 2023
Guidance remains largely in agreement on the general flow regime
through this coming week, with just some slight timing differences
regarding another approaching trough next weekend. A sprawling
ridge, centered over Manitoba, remains situated over most of central
Canada and the north-central US; a couple of troughs are located
over the East and West coasts. Max 500mb height anomaly at around
300m is centered just w of Hudson Bay. While this anomaly will
remain nearly stationary and weaken a little thru Tue, it will force
a shortwave currently traversing the Hudson Bay to drop southeast
Monday, deepening over New England or the Canadian Maritimes through
the middle of the work week. Resulting northerly flow over the Great
Lakes will bring cooler conditions to the area with temps trending
back to near early June normals over the next few days. Cooling will
be much more pronounced closer to Lake Superior. During the last
half of the week, a shortwave will round the ridge in Canada and
then drop southeast, working to maintain Northeast U.S. troughing
for the upcoming weekend. The ridge/trof configuration will
retrograde slightly as well. Warming back to above normal will occur
across Upper MI in advance of the wave during the latter part of the
week, followed by cooling again late weekend/early next week as
associated cold front passes. As for precipitation, while there has
been some rainfall over western and central Upper MI over the last
few days, a widespread soaking rainfall is needed across all of
Upper MI. Most of the area has had less than 50pct of normal pcpn
over the last 30 days with some areas under 25pct of normal. Here at
NWS Marquette, only 0.05 inches of rain has been recorded in the
last 15 days. Unfortunately, the pattern evolution favors a
continuation of overall dry weather for Upper MI thru this week. The
next chance of rain won`t arrive until late week when the
aforementioned shortwave rounding the ridge drops through, leading
to a cold fropa late Fri/early Sat. At this point, potential of
beneficial rainfall from this fropa looks very unlikely. Given the
lengthening period of little/no pcpn over most of the fcst area,
accompanied by many days of strong drying under very low RH, fire wx
concerns continue to increase daily and that includes the potential
of significant wildfires to develop.
Any shower activity quickly wraps up into Monday morning with
cooler, drier air working in as high pressure builds southward from
the Hudson Bay. Smoke from wildfires across Quebec may continue to
drift into the area amid north/northeast flow, with potential
impacts for air quality once again. Otherwise, expect quiet weather
while skies gradually clear out. Temperatures peak in the 70s across
most of the area, but will come in cooler in the 60s closer to
Superior. Though winds will be light, elevated fire conditions
continue to be the main concern as only spotty shower activity
overnight will have provided little by way of any relief from our
dry conditions.
The Hudson High in control over the area Tuesday through Thursday
will send in a significantly drier airmass, with PWATs plummeting to
as low as 0.25 to 0.5 inches. Temperatures continue to range in the
mid 70s across the area through the middle of the week before
starting to warm up Thursday (the exception continuing to be areas
along Lake Superior). Bone-dry, well-mixed soundings indicate a good
potential for dewpoints to mix out and relative humidity to plummet
each afternoon. Meanwhile, deepening low pressure near Nova Scotia
will lead to a tightening pressure gradient into the middle of the
week, with NE wind gusts up to 20 mph Tuesday and potentially up to
20 to 25 mph Wednesday, particularly over the eastern half of the
UP. Winds start to slacken Thursday. A period of breezy conditions,
in addition to prolonged dry weather and crashing RH, will lead to
elevated and potentially critical wildfire conditions for much of
the work week.
The surface high starts to break down Friday. Then, another
shortwave dropping into the Great Lakes late Friday will drag a cold
front through sometime friday night through Saturday. Expect
temperatures to turn a few degrees warmer Friday ahead of the
shortwave. Some spotty shower activity is not totally out of the
question during the day with decent lower level lapse rates and more
midlevel moisture working in - but there is a modest cap that
parcels would have to overcome. Better chances for showers arrive
Friday evening/night and continue into Saturday as the front works
through. Some timing differences persist among the guidance, but for
the nonce, the better window is Friday night through Saturday
morning. If the front is slower to work through, keeping chances for
convection going later Saturday, there would be a potential for some
thunder with some decent CAPE present in soundings across the
southern UP. Still, this would be more of a quick hit, instead of
the widespread, soaking rain we really need. Dry weather returns by
Sunday as another high amplitude ridge begins to build in again.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 640 PM EDT SUN JUN 4 2023
A cold front will move through overnight and bring in some MVFR
conditions with low clouds at IWD by Mon afternoon temporarily. CMX
will have VFR conditions mostly, but will have some MVFR
visibilities overnight with haze and then MVFR conditions with lower
clouds on Monday. SAW will have MVFR conditions with haze for most
of the period and VFR by Mon afternoon.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 348 PM EDT SUN JUN 4 2023
Winds continue to come in generally below 15 knots this afternoon
ahead of a weak cold front that is expected to cross Lake Superior
tonight. Winds won`t increase ahead of the front, but showers and
thunderstorms already moving towards northern Lake Superior could
push an outflow boundary with brief gusty winds southward across the
lake during the evening. These storms are likely to weaken quickly
and then dissipate as they move out over the waters. In the wake of
the front, high pressure over Hudson Bay will ridge south into the
Upper Great Lakes. N to NE winds on Mon and Tue will gust to 15-
20kt, strongest over far western Lake Superior w of the Apostles
where local effects will increase the winds. High pres ridging will
more firmly settle into the Upper Lakes for Wed and especially Thu.
Expect winds under 20kt on Wed and mostly under 15kt on Thu.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...TAP
LONG TERM...LC
AVIATION...07
MARINE...LC
Area Forecast Discussion...UPDATED
National Weather Service Morristown TN
938 PM EDT Sun Jun 4 2023
...New UPDATE...
.UPDATE...
Issued at 933 PM EDT Sun Jun 4 2023
Convection will continue its diminishing trend as the boundary
layer stabilizes with nightfall and the departure of a midlevel
shortwave trough. Patchy fog is likely to develop in areas that
received rainfall. Overall, the forecast is on track, with only
slight adjustments needed to PoPs and temperatures.
&&
.SHORT TERM...
(This evening through Monday)
Issued at 215 PM EDT Sun Jun 4 2023
Key Messages:
1. Isolated to scattered storms through this evening. Some of
these thunderstorms will be strong with isolated damaging winds
downing trees. Brief heavy rain and frequent lightning is also
possible.
2. Another round of storms are likely across east Tennessee and
southwest North Carolina again Monday afternoon and early evening.
Some strong thunderstorms are again possible.
Discussion:
Greatest coverage of have developed over the southeast Tennessee
and southwest North Carolina mountains. Isolated thunderstorms are
strong and likely producing strong and gusty winds and small hail.
Latest mesoanalysis shows MLCAPES of 1000-1500 and expected to
increase to near 2000. Key thermodynamic parameter is the DCAPE
which is between 800-1100 which is due to a good dry layer in the
mid-levels. Also, well-mixed steep low-level lapse rates with high
LCL along with plenty of melting of hail to potential produce
damaging winds. Down trees and power lines will be the main
impact.
Enough hail CAPE of 300-500 to enhance residence time to produce
marginal hail.
Complicated surface analysis with a wedge of cooler air east of
the Appalachians that has wrapped around the mountains. Another
boundary is moving south across Kentucky and will be approaching
southwest Virginia and northern Tennessee at the end of the day.
These boundaries along with orographic lift will be the focus of
convection development through this evening. A shear axis is also
moving south across the region and will be over southeast
Tennessee and southwest North Carolina this afternoon.
Overall, HREF and latest HRRR show scattered storms will continue
to develop area- wide with the greatest coverage of southeast
Tennessee and southwest North Carolina. Convection will diminish
soon after sunset due to loss of daytime heating.
For Monday, a frontal boundary will move slowly south across the
entire area. HREF and deterministic models show an enviroment
similar today and expected scattered storms to redevelop.
Instability and mid-level dry air will again produce a threat of
isolated strong storms.
&&
.LONG TERM...
(Monday night through next Sunday)
Issued at 215 PM EDT Sun Jun 4 2023
Key Messages:
1. Isolated to scattered storms will remain possible over
southeast Tennessee and southwest North Carolina Tuesday
afternoon. Some of these thunderstorms could be strong.
2. Another round of scattered storms are likely across southwest
Virginia and northeast Tennessee Wednesday afternoon. Some of
these storms could again be strong.
3. Unseasonably cool and dry airmass builds into the Tennessee
valley and southern Appalachians for the later half of the week.
Discussion:
Most of the extended forecast will be domininated by a persistent
upper trough across the northeast/eastern United States.
For Tuesday, the slow moving frontal boundary will be across far
southeast Tennessee and southwest North Carolina. Depending on
location of the frontal boundary during the afternoon, enough
instability is possible for isolated strong storms.
For Wednesday through Thursday morning, the persistent upper
trough across the east United States will swing another short-wave
and frontal boundary across the southern Appalachains. Best
forcing with the wave will be across the northern half of
Tennessee and southwest Virginia. Definitely disagreement on
degree of instability with this wave. However, due to the
unseasonably cool and dry air aloft can not rule out some hail and
potential gusty winds.
For Friday and Saturday, unseasonably cool and dry airmass will
build into the southern Appalachians and Tennessee valley. Low
temperatures will likely be some 10 to 15 degrees below normal.
For next Sunday, models are showing a pattern change with return
of moisture and instability and chances of mainly afternoon
convection.
&&
.AVIATION...
(00Z TAFS)
Issued at 712 PM EDT Sun Jun 4 2023
Showers and thunderstorms will be in the vicinity of CHA and TRI
for the next hour or two. With the loss of daytime heating, much
of this activity should dissipate within a few hours of sunset.
Fog is possible at CHA and TRI where rain moistened the near-
surface layer, and cooled temperatures. Confidence is low on how
low vis will drop. Scattered showers and thundstorms are expected
again tomorrow afternoon, which will be mentioned as a PROB30 at
all sites.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 86 63 89 66 / 70 60 30 10
Knoxville McGhee Tyson Airport, TN 87 64 87 62 / 30 20 30 10
Oak Ridge, TN 87 63 88 61 / 40 20 20 0
Tri Cities Airport, TN 84 59 81 55 / 30 20 30 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
SHORT TERM...DGS
LONG TERM....DH
AVIATION...DGS
Area Forecast Discussion
National Weather Service Pittsburgh PA
632 PM EDT Sun Jun 4 2023
.SYNOPSIS...
Slow moving low pressure will meander around the New England
area and adjacent Atlantic coastal waters through much of the
week. Cool and mostly dry weather is anticipated.
&&
.NEAR TERM /THROUGH MONDAY/...
No changes needed for the evening update. Expect and increase in
smoke coverage in the higher levels of the atmosphere this
evening, as smoke from the fires in Quebec is making its way
southward.
Radiational cooling should support lows near seasonal averages
overnight.
RAP smoke model indicates another surge of thick smoke possible
over the area Monday afternoon. Temperatures will cool to near
or perhaps slightly below seasonal normals.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
Upper low will continue to wobble and deepen through the short
term as the core of the system goes from MA coast to Nova
Scotia. Moisture starved short wave troughs will rotate around
the west side of this low toward the region, but little more
than some cu coverage is anticipated. With significant
precipitation not expected, our current 15 day dry spell will
continue at KPIT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Upper low will maintain its influence through the latter half of
the week, with yet another shortwave rotating around the
periphery Thurs-Fri. It appears the low will finally eject east
on Saturday with a more progressive northwest flow pattern
kicking in across the Great Lakes area. At this time, some of
the model guidance suggest another shortwave trough dropping
toward the Great Lakes toward the end of the period. The NBM has
the greatest chances for precipitation in the entire week long
stretch for late Sat-Sun.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
VFR will prevail through the TAF period as dry northerly flow
persists. Wind speeds will subside a bit tonight before picking
back up tomorrow during peak afternoon mixing. Upper-level
smoke from the Canadian wildfires will move across the forecast
area given the northerly winds, though surface/low-level
visibility should not be impacted.
.OUTLOOK...
High pressure will maintain VFR through late Tuesday. Confidence
is low that impacts associated with a passing cold front from
the north due to limited moisture.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...None.
OH...None.
WV...None.
&&
$$
SYNOPSIS...22
NEAR TERM...22
SHORT TERM...34
LONG TERM...Craven/34
AVIATION...Brown
Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1002 PM MDT Sun Jun 4 2023
.DISCUSSION...(This Evening Through Sunday)
Issued at 149 PM MDT Sun Jun 4 2023
Upper level analysis shows a mid/upper level high centered over
southwestern Manitoba with largely southeasterly flow aloft. Meager
mid-level flow continues again today (15-25 knots per 12z ROABs +
RAP analysis). At the surface, southeasterly flow dominates with a
corridor of dew points in the low 60s to upper 50s stretching through
western SD into northeastern WY. Despite the lack of shear/robust
wind profiles, the moist airmass has resulted in MLCAPE values
~500-1500 J/kg atop a well-mixed boundary layer and little MLCIN. As
such, scattered thunderstorms have formed across portions of the
western SD plains and northern/Wyoming Black Hills. No severe weather
is expected, however sub-severe (40-50 mph) gusts and small hail are
possible with any stronger convective cores. Additionally, given the
moist airmass, brief, heavy rain is likely with any convection this
afternoon and evening. Convection will gradually wane in coverage
late this evening.
The upper high will slowly retrograde southwestward over the coming
days, resulting in warm and drier conditions. A few isolated
thunderstorms are possible Monday, although large-scale ascent will
be absent and effective bulk shear will be marginal, limiting
coverage and intensity of any convection.
Dry and warm weather will continue into Wednesday before we start to
see a potential pattern shift for the latter half of the week. The
upper high/upper ridging will be slow to erode, squeezed between a
closed upper low over the SW US and a stronger upper low over the NE
US. Although the predictability in the evolution of this pattern is
low, increasing large-scale ascent will overspread the region (as
evident by weak q-vector convergence). This large-scale ascent
coupled with ample moisture/instability will support increased
chances for scattered showers and thunderstorms Wednesday through
next weekend. However, weak mid-level flow and subsequent meager
shear will preclude much of a severe weather threat during this
period.
&&
.AVIATION...(For the 06Z TAFS Through 06Z Monday Night)
Issued At 1000 PM MDT Sun Jun 4 2023
Isolated showers and thunderstorms are possible Monday afternoon,
mainly in western SD. Local IFR conditions and gusty winds with
any thunderstorms. Otherwise, VFR conditions will continue.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...None.
WY...None.
&&
$$
DISCUSSION...Eagan
AVIATION...JC