Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/09/24
Area Forecast Discussion
National Weather Service Dodge City KS
637 PM CDT Sat Jun 8 2024
.KEY MESSAGES...
- A large complex of thunderstorms is expected to cross
Southwest Kansas Saturday night, with damaging winds and heavy
rainfall the primary risks. The highest risk of damaging wind
is expected to focus along and north of US 50.
- Low clouds and much cooler Sunday.
- A rapid warming trend is expected next week.
&&
.UPDATE...
Issued at 608 PM CDT Sat Jun 8 2024
*** MESOSCALE DISCUSSION ***
At 23Z (6 PM CDT), several supercell thunderstorms were underway
across the High Plains of eastern Colorado. These storms were in
a very favorable warm, moist upslope environment characterized
by lower 60s dewpoints and 2000 J/kg MLCAPE along with 0-6km AGL
bulk wind shear vector magnitudes of 40 to 50 knots. This rich
severe weather environment extends well into Kansas. Pretty much
every high-end severe weather metric favors a prolonged, late-
evening into the overnight severe weather episode with either
one very large MCS transitioning into a MCC or at the very least
a couple smaller MCSs in close proximity.
Strong to marginally severe storms in the northern Texas
panhandle will likely continue to march northeastward toward far
southwest Kansas by mid-evening, with several of the latest runs
of the HRRR picking up on this and merging it with the Colorado
storms forming a massive severe MCS centered right across
southwest Kansas late tonight. High end severe wind reports are
the most likely risk tonight as the severe MCS matures,
especially when mid to upper 60s surface dewpoints become
ingested into the system. 70 to 80 mph wind gusts are expected
with the strongest convective updraft/downdraft interfaces
within the meat of the MCS tonight, really favoring a corridor
50 miles either side of a Scott City to Dodge City to Pratt
line. The risk of 70-80 mph wind gusts will be a bit lower later
in the night (after 11 PM CDT) and farther east as the boundary
layer cools sufficiently enough, however given the strength of
this MCS, boundary layer cooling may not be enough to weaken the
MCS strength much as surface to 850mb moisture transport vectors
are forecast to remain quite strong out of the east southeast.
&&
.SHORT TERM /THROUGH SUNDAY/...
Issued at 200 PM CDT Sat Jun 8 2024
Midday surface observations depicted a stationary frontal
boundary in the vicinity of the KS/OK border, with northeast
winds prevailing across SW KS. Moisture convergence was already
increasing along this boundary, with CAPE already exceeding 2000
J/kg, but expectation is for all convection to remain capped
through 7 pm, with forcing still removed, and an inversion in
place. The boundary will lift northward some through sunset,
with winds becoming more upslope/easterly, in response to the
approaching shortwave over the Colorado Rockies. Despite the
easterly boundary layer winds, temperatures will warm easily
into the mid 80s north, to the mid 90s adjacent to Oklahoma. MU
CAPE of 3-4,000 J/kg is expected to be common across SW KS by
evening. Still, removed all pops through 7 pm, with 12z ARW/NAM
dry through this time.
Numerous thunderstorms are expected to initiate as supercells over
northeast Colorado through 7 pm, evolving from the Front Range,
then rapidly grow upscale into an intensifying MCS (mesoscale
convective system) and enter the northwest zones in the 8-9 pm
time range. The environment this evening will favor rapid cold
pool/ outflow clustering, as the maturing MCS interacts with the
expected instability reservoir, producing bow echoes and
potentially particularly damaging winds. Wind gusts of 60-80 mph
are expected along the apexes of the strongest bowing segments,
probably favoring north and west of DDC this evening. Wind-
driven enhanced probability remains valid, with a much less
threat of hail greater than one inch in diameter. All convection
will be linear in nature in SW KS, so any tornado risk will be
very limited, and tied to QLCS mesovortex spinups along the
leading edge of the outflows when the MCS is near maturation
this evening.
Damaging winds are of particular concern during early summer
weekends, when many are outdoors enjoying recreational activities,
away from shelter. Ensure you have multiple ways to receive
warnings; some warnings will carry the destructive tag and
trigger WEA alerts on mobile devices when forecast wind gusts
reach 80 mph. Remain weather aware, and have a plan in place to
find shelter ahead of this thunderstorm complex tonight.
Damaging wind risk remains focused along and especially north of
US 50, with a 7 pm through 2 am time slot for the highest
impacts. Hatched probability (10% or greater)of significant
gusts (> 75 mph, hurricane force) is focused across the northern
half of the DDC CWA.
MCS is expecting to be exiting into central Kansas by 1 am Sunday
per the fastest guidance, 4 am per the slowest. All models show
widespread low stratus filling in developing behind the exiting
complex, as the MCS outflow pushes the old frontal boundary
southward again. Kept northeast winds toward the strongest side
of guidance through sunrise Sunday.
Sunday will be much cooler, with the combination of strong cold
advection (for June standards) and stratus working to hold
temperatures down through at least early afternoon. GFS/NAM agree
with an 850 mb temperature reduction of 6-9C compared to Saturday,
and where stratus can hold much of the day, afternoon temperatures
will be reduced to the refreshing 70s. Temperatures are expected
to fall back into the 50s Monday morning as weak high pressure
arrives in Kansas, but lingering cloud cover will limit the
cooling potential. Some overrunning/warm advection related
elevated showers/storms are possible favoring the southwest
zones Sunday night, but the forecast may be too wet here, with
much of this activity likely remaining south of SW KS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
Issued at 200 PM CDT Sat Jun 8 2024
Emphasis for additional rainfall and thunderstorms will
transfer to the west and south of SW KS on Monday. Pops will
strongly favor the southwest and western zones Monday, given
moist SEly upslope fow, and a midlevel weakness persisting near
southeast Colorado. Clouds will also be more prevalent across
these western zones Monday, with temperatures running several
degrees below early June normals. Midlevel shortwave trough or
weakness is forecast to drift eastward in the vicinity of SW KS
through Tuesday, and NBM correctly keeps chance category pops
for showers and thunderstorms for this feature. Flow and shear
will be very weak, but precipitable water will be high, favoring
non-severe disorganized/pulse convection with locally heavy
rainfall through Tuesday.
All models show aggressive warming Wednesday, as the weak
shortwave slides southeast of SW KS, and heights aggressively
build overhead. 12z EPS ensembles show a strong midlevel high
over 594 dm in strength building from Mexico toward Albuquerque,
New Mexico by 7 pm Wednesday. Afternoon temperatures will soar
easily into the lower 90s, and NBM may be too slow with the
magnitude of the warmup. The Mexican heat ridge builds even
stronger Thursday, with heights climbing well over 590 dm over
SW KS. 12z MEX forecasts a high of 99 at DDC Thursday, and
GEFS ensemble probability of 2m T > 100 is already 70-80%
Thursday afternoon. Given the very hot ensemble means, deterministic
solutions and NBM/MEX may not be hot enough, but regardless,
Thursday is expected to be hottest day so far this young summer
season. How much more rain we put in the topsoils between now
and then will play a role with any evaporative cooling, and
whether we can avoid triple digit heat. For non-summer lovers,
the good news is this heatwave is temporary, as ECMWF EPS shows
a shortwave trough eroding the ridge, reducing heights and
introducing another chance of showers and thunderstorms. Pops
and cooling trend from the NBM for next Friday and Saturday were
accepted.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 635 PM CDT Sat Jun 8 2024
A cluster of thunderstorms, many capable of producing heavy
rainfall and strong gusty winds, will cross southwest Kansas
between 00Z and 06Z. Wind gusts 50knots or higher will be
possible with these storms as they pass. Short term ensembles
show good agreement with this and also predict ceilings below
1000ft AGL (+70% chance) following the storms as gusty northeast
winds at 15 to 20 knots develop. These winds will gradually
decrease during the day as high pressure at the surface builds
into western Kansas. Low clouds will improve early, with low VFR
conditions developing throughout the day.
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Umscheid
SHORT TERM...Turner
LONG TERM...Turner
AVIATION...Burgert
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
634 PM CDT Sat Jun 8 2024
.KEY MESSAGES...
- A cold front will move through the area this afternoon and
evening with a band of showers and a few thunderstorms.
Widespread severe weather is not expected.
- Breezy northwest winds and seasonable highs are expected on
Sunday, followed by breezy northeast winds and seasonably cool
conditions on Monday.
- A gradual warming trend is expected from Tuesday onward with a
return of above-average temperatures by the end of the week.
&&
.DISCUSSION...
Issued at 216 PM CDT Sat Jun 8 2024
Today and Tonight:
Recent surface, radar, and satellite observations
depict a low pressure system centered near Clinton, Iowa along a
surface cold front extending from southern Wisconsin into eastern
Iowa and central Missouri. A narrow tongue of low-level moisture
characterized by surface dew points in the low to mid 60s continues
to slide into northwestern Illinois ahead of the front and just to
the south of subtle low-amplitude upper-level shortwave propagating
within a seasonably strong upper-level jet across the central Great
Lakes. Pockets of clearing across northern Illinois combined with
increasing low-level moisture is allowing for the development of
shallow low-level instability, with the most-recent RAP analysis
indicating around 500 J/kg of MLCAPE (50-75 J/kg of which in the
lowest 3 km).
Over the next few hours, coverage of ongoing showers near the
Wisconsin state line will increase and pivot southeastward over
northern Illinois within the shallow but destabilizing boundary
layer. A few thunderstorms remain possible amongst otherwise
scattered showers within the southeastward-shifting zone. With
strong low- to mid-level shear (thanks to a stark shift in wind
direction along the front and a close proximity of the upper-
level jet to our north), any sustained updrafts will have the
opportunity to develop transient low- to mid-level rotation and
become a low-topped supercell. As a result, we cannot rule out a
report of a funnel cloud or even brief tornado this afternoon,
particularly near the best overlap of low-level instability and
near-surface vorticity along the front. Extrapolating the
positioning of the low-level moisture axis and arrival timing of
the front, such a threat for funnel clouds should materialize
near I-80 between 3 and 6 PM. Now, this is not an environment
that appears supportive of damaging tornadoes, and the most
likely scenario is that a band of showers with an embedded
lightning strikes moves through without any fuss. Nevertheless,
move indoors if you see a funnel cloud or otherwise hear
thunder. The axis of showers and embedded thunderstorms will
move southeastward into northwestern Indiana this evening.
Behind the front, an increase in northerly winds will cause
waves on Lake Michigan to quickly build to 2-4 feet. While not
an ideal beach day, be prepared for quickly changing conditions
if out on the water. Overnight lows tonight will range from the
low to mid 50s.
Sunday and Monday
As upper-level cyclonic flow gradually moves through the Great Lakes
Sunday into Monday, several embedded short-wavelength troughs
will move overhead. As a result, Sunday will be marked by
seasonable temperatures in the mid to upper 70s and breezy
northwest winds. Winds will turn onshore on Monday, leading to a
seasonably chilly day with highs in the lower 60s lakeside to
lower 70s inland. While our forecast is dry both days, it
wouldn`t take much to squeeze out a few sprinkles during both
afternoons as low-level lapse rates steepen and allow for
appreciable depth to cumulus clouds. Also, onshore winds will
cause choppy waves and dangerous swimming conditions across all
Illinois and Indiana Lake Michigan beaches on Monday.
Tuesday Onward:
A gradual warming trend is expected Tuesday onward. Ensemble model
guidance continues to advertise summer-like (and above-average)
temperatures returning by the end of the week, following by
increasing humidity levels (and chances for thunderstorms) sometime
during the 3rd week of the month.
Borchardt
&&
.AVIATION /00Z TAFS THROUGH 06Z MONDAY/...
Issued at 634 PM CDT Sat Jun 8 2024
Key Messages:
- Rain ending early this evening with MVFR/IFR ceilings ending
soon thereafter
- Breezy northwesterly winds tomorrow afternoon
The back edge of this afternoon`s rain is moving through the
Chicago metro at the time of this writing, and this rain and
its associated MVFR/IFR visibility reductions will cease prior
to 01Z at ORD and MDW and 02Z at GYY. The back edge of the
attendant MVFR/IFR stratus deck is lagging behind the back edge
of the precipitation, but a return to VFR conditions is favored
to occur approximately 1-3 hours after the rain has ended.
Winds will go light tonight but should pick back up again after
sunrise tomorrow. Initially, northwesterly gusts to around 20
kts can be expected tomorrow morning, but gusts closer to 30
kts are likely to become common during the afternoon as mixing
heights rise markedly. Towards the end of the current TAF
period, a southward-sagging cold front will produce a northerly
wind shift, with winds likely to turn east of 360 degrees at
ORD and MDW towards the end or just beyond the current end time
of their 30-hour TAF period.
Ogorek
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.
&&
$$
Visit us at weather.gov/chicago
Area Forecast Discussion
National Weather Service Pueblo CO
547 PM MDT Sat Jun 8 2024
.KEY MESSAGES...
- Severe thunderstorms, with all hazards, expected through this
evening across the eastern plains, mainly along and north of
Highway 50.
- Thunderstorms, a few strong to severe, possible Sunday and
Monday across the mountains and adjacent plains with risks
transitioning towards hail and heavy rainfall capable of
producing localized flash flooding.
- Heat build backs into the area by the middle part of next
week.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 334 PM MDT Sat Jun 8 2024
Severe risk continues this afternoon across the plains, with latest
radar imagery showing more isolated thunderstorm development across
the Pikes Peak region along the Raton Mesa. In these areas have seen
lee troughing occur while a well defined shortwave moved overhead.
Latest RAP analysis showing some CIN remaining in place, which has
likely limited any robust updrafts at this. However, guidance now in
fair agreement with any remaining CIN eroding here in the near term,
with intensity of the current storms likely increasing. While can`t
completely rule out a strong to severe storm over the far southern
area near the Colorado and New Mexico border this afternoon, think
they will be less likely there given some drier air, lower
instability, as well as lower shear. From Pueblo up towards the
Springs, will see more robust updrafts over the next couple of
hours, given a steady southeast wind advecting low 50s dewpoints
into this area, resultant CAPE values around 1000 j/kg, and shear
upwards of 35 to 45 kt. In these areas this afternoon, expect hail
up to around 1.5 inches and wind gusts up to 60 mph. Think this risk
will continue through around the 5 pm time frame, with development
likely shift to the east.
By early this evening, will see the isolated to widely scattered
severe storm development to shift east into the plains. Once again,
given the above mentioned moisture, instability, and wind shear
values, think the highest risk of severe storms will be along and
north of the Highway 50 corridor. Will closely monitor the severe
threat for Baca county though, as observational data showing some
higher dewpoints inching into this area. Along and north of Highway
50 and especially near the Colorado and Kansas border, low to mid
60s dewpoints and steep lapse rates are yielding CAPE just above
3000 j/kg. This much higher instability and moisture along with
increasing shear will not only support the continued severe risk,
but will support the risk for higher end wind gusts and larger hail.
This is especially as CAMS are indicating more upscale development
into linear segments. So, will continue to message a high chance for
winds up to 80 mph and large hail up to around 2 inches for areas
northeast of a Las Animas to Springfield line. The risk for a few
tornadoes also remains for these areas even if linear convection
develops. Should see the severe risk quickly lower by around the 7
pm time frame but as instability remains in place, can`t rule out
additional thunderstorm development into the late evening time
frame. While a low confidence scenario at this time, its possible
the instability axis swings back into the I-25 corridor and
southeast mountains. If this were to occur, could see at least
isolated development in these locations.
&&
.LONG TERM /SUNDAY THROUGH SATURDAY/...
Issued at 334 PM MDT Sat Jun 8 2024
By Sunday, will see rising heights and weakening flow, but will see
moisture and instability remain in place. It does look as if the
moisture/instability axis shifts further west, with increased
chances for showers and thunderstorms over the mountains and
mountain valleys. Guidance is in fair agreement with bringing mid to
upper 50s dew points right up to the southeast mountains, and with
CAPE values easily in the 1000-1500 j/kg range and quite possibly
approaching 2000 j/kg. While there is weakening flow that will
support less organized development on this day, I think the risk for
hail and damaging winds will remain. Overall setup could support the
risk for more wet microbursts/damaging winds on Sunday. The highest
risk for severe storms will likely be across the southeast mountains
into the I-25 corridor. Additionally, still closely monitoring the
potential for heavy rainfall and flash flooding, for these same
areas. With higher moisture content air, forcing/focus right into
these areas, and with slow storm motions, definitely have concerns
for flash flooding. Did debate issuing a Flash Flood Watch for these
areas on Sunday, but have opted not to at this time and will let
later shifts take a look at additional guidance.
The risk for heavy rainfall and flash flooding continues Monday, as
upper energy evolves into a closed low on this day. Guidance begins
to really diverge with this system, most importantly placement of
this system. So, while there might be a slightly higher chance for
precip development to shift more across the Continental Divide on
Monday, think guidance could easily shift back east. So, at this
time, will continue to message more widespread precip development
over much of southern Colorado. Severe risk does lower, but will
remain possible just given the nature of closed upper level lows. It
does appear that by Tuesday, we`ll see coverage of precip chances
lower that continues on Wednesday as upper ridging is the trend.
This will return building heat to the area though, with well above
normal temperatures in the 80s and 90s, and quite possibly 100
degrees, returning to southern Colorado by mid week.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 547 PM MDT Sat Jun 8 2024
VFR conditions are expected to prevail for KALS, and mostly for KPUB
KCOS, throughout the forecast period. There will be some MVFR and
possibly IFR criteria during the morning hours for KCOS and KPUB due
to low CIGs, mainly between 10-16Z at KCOS and 12-16Z at KPUB Winds
will be synoptically influenced by a shortwave transitioning over
the region. FROPA will occur around 01Z at KCOS and KPUB, but may
occur sooner if the boundary is accelerated by outflow from
convection to the northeast, this will cause winds to switch to a
NE`ly direction at both terminals. Winds at KALS will also switch
around to a more NE`ly direction later this evening and then
eventually go L&V. Winds will begin to increase out of the SW at
KALS and out of the ESE-SE at KCOS and KPUB, by tomorrow afternoon
with gusts between 25 to 30 kts expected, increasing more towards
the end of the forecast period. There will be developing convection
in the vicinity of KALS which may move on station from 20-24Z, SHRA
and possible VCTS is also expected in the vicinity of KCOS and KPUB
after 20Z as well, although less confident that it will move on
station until after the forecast period. If SHRA/TSRA does develop,
it could temporarily reduce CIGs and VIS to MVFR/IFR criteria. It
could also result in periodic windshifts and increased wind speeds
for all terminals. -Stewey
&&
.HYDROLOGY...
Issued at 334 PM MDT Sat Jun 8 2024
Rapid snow melt will continue across the mountains leading to
elevated flows along the Arkansas River from Leadville to Canon
City through Monday as well as on smaller creeks and streams in
and near the mountains. Flows are expected to remain within
banks for most locations along the Arkansas River but fast flows
can still be dangerous. Slightly cooler temperatures may
decrease the snow melt Sunday and Monday, however the potential
for heavy rainfall will increase both days for the southeast
mountains and adjacent plains. This could cause localized flash
flooding and push flows above the projected bank full forecast
for localized areas depending on where the rain falls.
Latest projections place the heaviest rainfall across Teller,
western El Paso and Fremont counties on Sunday though the flash
flood risk still looks localized. Continue to monitor weather
forecasts closely.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...RODRIGUEZ
LONG TERM...RODRIGUEZ
AVIATION...STEWARD
HYDROLOGY...KT