Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/31/24
Area Forecast Discussion
National Weather Service Bismarck ND
934 PM CDT Thu May 30 2024
.KEY MESSAGES...
- Areas of frost in low-lying areas of southwest North Dakota
tonight.
- Seasonably cool temperatures on Friday with scattered
afternoon showers and thunderstorms.
- Dry Saturday, then chances for showers and thunderstorms
return later Saturday night through early next week.
&&
.UPDATE...
Issued at 932 PM CDT Thu May 30 2024
Latest satellite trends show a mostly clear sky over southwest
North Dakota this evening. Some mid level clouds are developing
from the northern Black Hills to the Standing Rock Reservation.
These clouds are forecast to remain southeast of Hettinger
through much of the night, with clouds increasing from Sioux
and Grant Counties to the north and east. There is still a bit
of a west-northwest breeze as of this writing, but winds should
weaken and turn more to the west-southwest as surface high
pressure builds over southeast Montana. Dewpoints in southwest
North Dakota are in the lower to mid 30s, and HRRR/RAP/NBM
projects these values to hold through the night. Taking all this
into consideration, we have issued a Frost Advisory for most of
southwest North Dakota, in effect from 2 AM to 7 AM MDT. Areas
outside the advisory could possibly see some patchy frost,
mainly in the favorable Glen Ullin to Beulah-Hazen corridor, but
the highest probabilities for temperatures falling near freezing
tonight are in low-lying areas in the southwest, including Mott,
Hettinger, Bowman, Amidon, and Medora.
UPDATE
Issued at 655 PM CDT Thu May 30 2024
Shower activity is now confined to northwest North Dakota. One batch
of showers with occasional lightning has lifted into southeast
Saskatchewan, while another batch with no lightning observed is
entering from northeast Montana along and north of the Missouri
River. With up to 500 J/kg still present, will maintain a slight
chance of a thunderstorm in the forecast for the evening. All
showers are forecast to dissipate or lift north into Canada later
this evening.
We will continue to monitor satellite trends this evening for the
possible need of a Frost Advisory in southwest North Dakota later
tonight into early Friday morning. The main area of focus is a batch
of mountain wave clouds from the Bighorns to Black Hills, extending
north toward the ND/SD border. If these clouds remain south of the
state, which latest RAP guidance favors, temperatures could easily
fall into the mid 30s in low lying areas.
&&
.DISCUSSION...
Issued at 233 PM CDT Thu May 30 2024
A blocking upper level pattern will keep an upper level low situated
over the central Canadian Prairie Provinces through the weekend. A
combination of shortwaves rotating around this low, and impulses
coming off the Pacific, tracking across the Northern Rockies and
below the Canadian low will influence the weather over our area
through the weekend. This low eventually gets pushed east as a
stronger wave coming off the Pacific moves into the Region early
to mid next week.
Currently, showers and a few thunderstorms are lingering over
the far southern James River Valley but should exit the area
this afternoon. This activity is situated along a warm
front/trough that is currently exiting the JRV. Breezy westerly
winds behind this front have developed over most of western
and central North Dakota. A trailing cold front will sweep
through the area later this afternoon and tonight. There may be
a few showers trying to move into western ND late this
afternoon/early this evening, but with very dry air southwest,
the potential for shower activity will likely be limited to the
west central/northwest and any thunderstorm activity should be
limited to the far northwest corner.
Late tonight and early Friday the focus shifts to temperatures.
Current forecast trends clear out much of western and central ND
tonight. By 12Z Friday, surface high pressure is situated over
western SD with mid and high level clouds beginning to work back
into western ND from the southwest. However, very dry air is
situated over the area overnight. The NAEFS SA table shows a
signal for dry PWATs over western ND. IF winds drop off tonight,
which it looks like they may in the southwest, and skies remain
clear, we could see some temperatures in the middle 30s
southwest, resulting in Frost. Given our normally cool areas
west of the Missouri River extend north and east to the
Beulah/Hazen area and towards eastern Lake Sakakawea, the area
of mid 30s could extend even farther north and east than we are
currently advertising. NBM 10th percentile was only depicting
some upper 30s and no frost, so we combined some MOS based
guidance to trend temperatures down a bit over the southwest.
MET/MAV guidance for Hettinger is 34. There is the potential
that mid level clouds could move into the area, keeping
temperatures from dropping into the 30s at all. Will hedge
towards the cool side and pass along to the evening shift.
Potentially we could see a frost advisory if ideal conditions
are met.
After a cool start Friday, diurnal heating, combined with
another upper level impulse will fire afternoon showers and
thunderstroms. The lack of heating is expected to keep the
severe threat to a minimum and SPC is currently carrying a
general thunderstorm risk and this looks reasonable.
Saturday will bring mostly sunny skies with warmer temperatures.
Highs should be mainly in the 70s statewide. Late Saturday night
and Sunday, an impulse emanating from the Pacific will move
into the area bringing another round of showers and
thunderstorms, with a stronger wave moving into the Region early
next week. There is some some indication that the far southeast
could see a few stronger storms on Sunday but this remains
quite a ways out. Still something to monitor as we head into the
weekend. Uncertainty in the deterministic models and ensembles
increases as we head into next week, but the pattern will likely
remain active through at least Monday and Tuesday.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 655 PM CDT Thu May 30 2024
VFR conditions are expected to prevail through the forecast period.
Scattered showers remain possible across northwest North Dakota this
evening, and another round of afternoon showers with a few
thunderstorms is possible across most of western and central North
Dakota on Friday. Strong westerly winds will diminish to around 10
kts later this evening and only increase slightly on Friday.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
Frost Advisory from 2 AM to 7 AM MDT Friday for NDZ031>033-040-
041-043-044.
&&
$$
UPDATE...Hollan
DISCUSSION...TWH
AVIATION...Hollan
Area Forecast Discussion
National Weather Service Cheyenne WY
740 PM MDT Thu May 30 2024
.UPDATE...
Issued at 735 PM MDT Thu May 30 2024
Current forecast for tonight and early Friday morning appears on
track, with late night convection picking up between 10 PM and 1
AM. A few of these thunderstorms may become strong to severe
overnight through early Friday morning with large hail the
primary threat. Added fog to the forecast for the I-25/I-80
Junction and areas east of I-25 towards the southwest Nebraska
Panhandle. Expect outflow winds from thunderstorms and
additional moisture advection along the Laramie Range and
Cheyenne Ridge. High resolution models continue to indicate a
possibility of dense fog around sunrise Friday. Added patchy fog
with areas of fog for the southern Laramie Range. If
thunderstorms become too numerous, fog may have a hard time
developing...so left out the mention of dense fog for now.
&&
.KEY MESSAGES...
- Potential for a late night severe thunderstorm event in the
Nebraska Panhandle late this evening into the early morning
hours Friday.
- Daily chances for precipitation continue into the weekend
before turning drier early next week with above average
temperatures.
- After a weather disturbance produces a slight chance for
showers and thunderstorms on Sunday, dry and warm weather will
prevail for Monday through Thursday.
&&
.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 200 PM MDT Thu May 30 2024
Beautiful day ongoing this afternoon with only some upper level
clouds being observed across the CWA. Most of Wyoming under the
influence of surface high pressure...in between a departing
cold front across central Nebraska and an approaching cold front
to the northwest. Surface trough extends from north central
Colorado...north into the west slopes of the Laramie Range and
then northwest into northern Carbon County.
Latest mesoscale guidance continuing to forecast a late show
tonight for convection...focusing on thunderstorms developing
after 06Z. HRRR most aggressive with development and coverage
over Cheyenne and Kimball Counties...possibly into the eastern
half of Laramie County. MUCAPE values near 1000 to 1500 J/KG
over these areas this evening. Did add severe wording into the
southern Panhandle for late this evening into early Friday for
thunderstorms.
Upper shortwave tracks across eastern Montana/northeastern
Wyoming Friday afternoon for another rounds of scattered
afternoon and evening showers/thunderstorms.
Saturday may perhaps be our best chance for severe convection as
a dryline develops across southeast Wyoming and pushes eastward
into western Nebraska. Depending on the timing of this dryline
push...could see supercells developing across the Panhandle
Saturday afternoon. Storm Prediction Center already has a Slight
Risk area identified for the Panhandle Saturday afternoon.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 200 PM MDT Thu May 30 2024
Sunday...A progressive and low amplitude shortwave trough aloft is
progged to move across the forecast area around peak heating.
Although low and mid level moisture looks rather scant, there should
be enough moisture for isolated to widely scattered afternoon
showers and thunderstorms, mainly east of Interstate 25. A bit
warmer than Saturday with 700 mb temperatures near 11 Celsius,
yielding maximum temperatures in the upper 70s west of I-25, with
80s east of I-25.
Monday...Looks like the warmest day of the week with 700 mb
temperatures near 15 Celsius, yielding high temperatures from the
mid 80s to mid 90s. Warm temperatures aloft and limited low and mid
level moisture will likely keep this day dry.
Tuesday...A progressive shortwave trough aloft moves across the
northern Rockies, sending a dry cold front across our counties, and
dropping high temperatures some 5 to 10 degrees.
Wednesday-Thursday...Ridging aloft builds across our forecast area,
producing mostly clear conditions and warm temperatures with 700 mb
temperatures near 14 Celsius on Wednesday and 17 Celsius on
Thursday. Warm temperatures aloft will likely inhibit convective
development.
&&
.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 501 PM MDT Thu May 30 2024
A complex forecast for all terminals east of the Laramie Range
due to the threat of overnight thunderstorms. KLAR and KRWL
should remain VFR throughout the TAF period, with little concern
for nocturnal convection over these sites. High clouds and
relatively calm winds expected at these terminals.
For remaining terminals (KCYS, KBFF, KCDR, KSNY, KAIA) nocturnal
thunderstorm activity will be a concern for all sites.
Thunderstorm activity expected to begin just after 06Z and
continue through about 13Z. Expect lowering ceilings with these
storms, as well as gusty and erratic winds around any storm that
develops. Behind the storms, could see ceilings dropping
towards the IFR category by sunrise at KCYS and KSNY. Gusty
winds initially at KCYS and KBFF before all winds decrease
overnight, except when thunderstorms are present.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
UPDATE...TJT
SHORT TERM...GCC
LONG TERM...RUBIN
AVIATION...AM
Area Forecast Discussion
National Weather Service Des Moines IA
624 PM CDT Thu May 30 2024
...Updated for the 00z Aviation Discussion...
.KEY MESSAGES...
* Showers and thunder slide in from the west late this afternoon,
tonight, and through Friday. Very low strong to severe threat.
* Additional/periodic shower/storm chances into next week, but model
spread continues to make details hazy. Mid-week next week may be
next opportunity for stronger storms.
* Warming temperatures by late weekend into next week. Highs
into the mid 80s at times.
&&
.DISCUSSION...
Issued at 226 PM CDT Thu May 30 2024
Conditions early this afternoon remain largely pleasant across the
area with temperatures into the mid and upper 70s. It has been
notably breezier across western and central areas, gusting into the
mid to upper 20s mph at times out of the SE, with the tightening
surface pressure gradient. Cloud cover has been slow to move over
the area, with largely translucent high level cloud cover streaming
across at this time, but will gradually increase as showers/storms
continue to encroach from Nebraska. Many may be able to enjoy
another fairly pleasant evening before said precipitation chances
slide in.
Short-term guidance has continued to latch onto the general split
and fading of shower/storm activity as they enter and move across
the state. This is largely driven by the northern stream trough and
southern stream shortwaves being less in-phase and the core of their
forcing being centered north and south of the state respectively.
That also led to lingering and unusually high variance within
overnight (06z) CAM guidance through Friday. The 12z runs showed
more consistency, coming closer to extended run HRRR solutions, with
weakening convective activity entering western areas of the CWA
around/after 03z and struggling mightily to even reach I-35
overnight. By daytime tomorrow, the split forcing becomes more
apparent with southern and northern areas most likely to see
appreciable precipitation, including thunder as weak boundary slides
into northern/northwest Iowa. The risk for strong/severe remains
very low with sub-par shear profiles and thermodynamic profiles
tending to yield weak MUCAPE of only a couple/few hundred J/kg.
Initial storms this afternoon/evening may have a few stronger gusts
with dry profiles in place. Overall activity will continue to trend
downward Friday night and may be mid-day Saturday before exiting
eastern portions of the CWA.
Upper level flow pattern becomes more zonal across much of the CONUS
by the end of the weekend into next week, allowing multiple
shortwaves to potentially initiate periods of showers and non-severe
storms. With the subtle nature of the shortwaves, model depictions
continue to vary in strength, coverage, and timing. This continues
to result in broader PoPs than what will surely occur. The next
potential strong/severe threat window continues to look like mid-
week next week as a larger trough drops out of the PNW and southern
Canada. That would be the time frame to watch for more impactful
weather.
Temperatures remain slated to warm by late weekend into next week,
bringing highs back into the mid 80s, but confidence too is hampered
by the discrepancy shortwave handling.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 620 PM CDT Thu May 30 2024
VFR conditions are expected to prevail through the period, with
the exception of some reduced flight conditions should any
stronger showers or thunderstorms pass near a site. Showers are
expected to start overnight tonight and continue intermittently
through much of the day tomorrow, however, confidence is low in
exact timing for each site due to the scattered nature.
Therefore, have tried to time out the most likely periods at
sites, if possible. Otherwise, prolonged periods of VCSH have
been included for those that have less definite breaks in
precipitation. Some occasional lightning may be possible as well
tomorrow, but left out of TAFs at this time.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION...Curtis
AVIATION...Dodson
Area Forecast Discussion
National Weather Service North Platte NE
742 PM CDT Thu May 30 2024
.KEY MESSAGES...
- Locally heavy rainfall may develop in a few areas of swrn and
ncntl Nebraska tonight. Isolated severe wind gusts are also
possible.
- Severe weather is possible Friday, Saturday and Sunday but the
chances Friday are mainly across far swrn Nebraska and the srn
Panhandle. The chances Sunday are across far ncntl Nebraska.
Saturday will be the most likely day for severe storms,
potentially affecting a good portion of wrn Nebraska from
about 4 pm CDT onward.
&&
.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 238 PM CDT Thu May 30 2024
Winds aloft are very weak this afternoon, 10-20kts at h500-300mb.
Meanwhile, moisture is pooling ahead of a cold front across
ncntl/swrn Nebraska leading to PWAT above 1 inch. The CAMs are
signaling asynoptic southwest storm development with storms firing
across ncntl Nebraska this afternoon and building, or developing
southwestward into swrn Neb this evening. The southward moving cold
front will be close behind marking an end to sfc based storm
development.
In a nutshell, locally heavy rainfall is possible in spots. The
NANnest is showing a 4-inch total near Sargent by 00z with several 3
inch totals further south, all localized, by 06z tonight. Given the
4.3 inch total reported in Sherman county this morning by WFO GID,
discrete southwestward developing storms producing locally heavy
rainfall would appear to be operative storm mode late this afternoon
and tonight.
A check on BUFkit shows a plume of dry air in the midlevels moving
in from the west. This could lead to the demise of a thunderstorm
and cause damaging wind gusts at the same time. Such was the cause
near KVTN last night with a recorded gust to 79 mph.
The POP forecast tonight leans toward the aggressive CAMs but
limits POPs to 50 percent.
The aforementioned cold front will be located across nrn KS Friday
morning and then lift north as a warm front Friday and Friday night.
Most model solutions offer little opportunity for rain during
this time but the RAP and HRRR sense upper level support moving
through the Rockies and moisture at the lower levels. The result
is at a minimum, periods of drizzle or light across wrn
Nebraska Friday into early Saturday morning with the potential
for showers and thunderstorms associated with the upper level
support.
SPC suggested severe weather concerns late Friday for an upscale
thunderstorm complex emanating off the Colorado Front Range and
the Cheyenne Divide. The slight severe weather risk brushes a
small portion of southwest Nebraska.
Given the wide range of model solutions Friday and Friday night, the
POP forecast leans on SPC and WPC for guidance. POPs are less than
40 percent.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 238 PM CDT Thu May 30 2024
Additional opportunities for severe weather are Saturday and
Sunday. Forecast solutions, in terms of storm coverage Saturday,
range from the potential for upscale growth in the NAMnest to a
more singular severe storm complex in the NAM12 to nearly
nothing in the ECM. The ECM shows the storms remaining mostly in
Colorado. Western Nebraska will be in the warm sector so it is
likely the model differences are a result of differences in the
location of the low level focus and upper level support shown in
the models. Later forecast will resolve this. As it stands now,
the NAM shows 40-50kt h500-300mb winds pushing into wrn
Nebraska Saturday afternoon, effective shear 40 to 60kts and 21z
MLCAPE around 2500J/KG. This would certainly support severe
storm development with swrn Nebraska and the srn Panhandle the
favored location.
The situation Sunday becomes more uncertain as the models focus
convection as far north as ND and MN in the NAM to cntl Nebraska in
the ECM. Regardless, winds aloft will be strong, 30-40kts at h500-
300, effective shear is 40-50kts and MLCAPE 1500-2000 J/KG,
according to the NAM. This would support an isolated severe storm
potential; the BRN is 35 or less.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 737 PM CDT Thu May 30 2024
A few thunderstorms will be scattered about the region tonight,
but widespread precipitation is not expected. Winds will
generally be from thr east-northeast at 5-15kt through Friday.
Some threat for lower MVFR ceilings to develop across portions
of southwest Nebraska late tonight and linger through Friday
morning.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...CDC
LONG TERM...CDC
AVIATION...Taylor
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1055 PM CDT Thu May 30 2024
.KEY MESSAGES...
- Another round of showers and scattered thunderstorms will move
across the area late Friday into Saturday.
- There will be a continued chance for showers and thunderstorms
into next week with temperatures climbing above normal.
&&
.SHORT TERM... (Through Late Friday Night)
Issued at 221 PM CDT Thu May 30 2024
We are enjoying another dry day with near normal temperatures as a
surface high centered over the Great Lakes continues to usher
relatively dry air into the area. The HREF is showing the upper
ridge currently over western Missouri moving east across the area
tonight keeping the area dry. This will change tomorrow as the
trough over the Plains will deepen on Friday and then move across
Missouri and Illinois on Friday night. The GFS/NAM is in reasonable
agreement showing the attendant surface low moving northeast across
the CWA late Friday night into Saturday. Latest runs of the CAMS
including the HRRR are showing that the chance for showers and
thunderstorms will not move into central Missouri until late
tomorrow morning, with likely/categorical PoPs spreading from west
to east across the CWA tomorrow afternoon and evening as there will
be stronger ascent from the upper low and a low level jet. These
high chances will not exit the eastern CWA until late Saturday
afternoon when upper low moves east of the area. Overall, rainfall
amounts look to be on the order of 0.5-1.0"+ with this system, but
with PWATS near 1.7", a few of the showers and thunderstorms
will be capable of producing some locally heavy rainfall.
Temperatures will be close to normal through Saturday as 850mb
temperatures remain near 10C with the increased clouds and rain
chances with the upper low.
Britt
&&
.LONG TERM... (Saturday through Next Thursday)
Issued at 221 PM CDT Thu May 30 2024
Global models and the LREF is showing the pattern becoming quasi-
zonal early next week before an upper trough enters the north
central CONUS by the middle of next week. This still causes a
certain amount of uncertainty with regards of the timing and
strength of the shortwave troughs that will move across the area
Sunday into Tuesday that will bring showers and thunderstorms to the
region. At this point, it still appear that Sunday into Sunday
evening will have lower chances for rain (10-30%) as a shortwave
ridge moves across the area, while there will be higher chances(40-
60%) on Monday into Tuesday as a pair of troughs move across
Missouri and Illinois. It should be noted that while some of the
raw QPF from the global models looks too high because of convective
feedback, there could be some locally heavy rainfall as the LREF has
PWATS near 1.6". There will be an additional chance of showers and
thunderstorms into Wednesday as the attendant cold front of the
upper low moves across Missouri and Illinois. While there is some
potential for a few strong storms next week, the CAPE/shear setup is
not particularly impressive for organized severe storms.
It still looks like we are on track for a warm up next week as the
LREF is showing 850 temperatures climbing to near 20C between Monday
and Wednesday with low level southwesterly flow before the cold
front moves through midweek. The NBM 75th percentile for highs are
showing highs AOA 90 degrees early next week, so few spots certainly
could reach 90 ahead of the cold front where there is less rain and
more sun. Overall confidence in the warmup remains high as the NBM
IQR is around 5 degrees or less ahead of the cold front, but then
increases to around 10 degrees behind the cold front next Thursday.
Britt
&&
.AVIATION... (For the 06z TAFs through 06z Friday Night)
Issued at 1051 PM CDT Thu May 30 2024
No major changes to the timing of the onset of precipitation on
Friday. Through mid morning Friday expect VFR flight conditions.
Showers will begin to move into KCOU and KJEF between 17z and 20z
Friday, while they won`t move into KUIN and St. Louis metro TAF
sites until between 22z Friday and 00z Saturday. Otherwise by late
afternoon through Friday evening, coverage and intensity will
increase with MVFR ceilings moving in after 00z-03z Saturday.
Also, added vicinity thunderstorms during this period as well.
As for winds, they will persist out of the southeast through the
entire forecast period, though could see gusts near 20kts at times
during the day on Friday.
Byrd
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Memphis TN
1046 PM CDT Thu May 30 2024
...New UPDATE...
.UPDATE...
Issued at 1045 PM CDT Thu May 30 2024
Dry easterly flow continues at the surface resulting in another
fine evening across the Mid-South. However, things will be
changing soon. A first shortwave will approach the region later
tonight into Friday morning with chances for showers and a few
thunderstorms spreading across the area. A more significant piece
of energy will push into the region Friday late afternoon into
Friday night with increasing moisture and instability. This could
lead to a few severe storms mainly over east AR and northwest MS
along with locally heavy rainfall.
&&
.SYNOPSIS...
Issued at 312 PM CDT Thu May 30 2024
Wet and unsettled weather will begin on Friday as a convective
complex of storms moves into the area. A few strong to severe
storms are possible with damaging winds, heavy rainfall, and the
potential for a tornado or two. Rain chances will remain high
through Saturday as a cold front moves across the area. Medium
chances for showers and thunderstorms will continue each day
through the middle of next week as a series of upper level
disturbances move through the region. Temperatures will remain
near normal with highs in the 80s each day.
&&
.DISCUSSION...
(This evening through next Wednesday)
Issued at 312 PM CDT Thu May 30 2024
A beautiful late spring across the Mid-South. Temperatures are in
the low to mid 80s with sunny skies and low humidity. The airmass
will undergo a significant change over the next 12-24 hours as a
plume of rich moisture moves into the region. For context, PWATs
are one standard deviation below normal for this time of year and
will surge to 1.5 standard deviations by tomorrow afternoon. The
marked increase in moisture will yield the potential for a few
strong to severe thunderstorms on both Friday and Saturday.
Additionally, heavy rainfall will become a threat for areas along
and west of the Mississippi River through Saturday as multiple
rounds of rainfall occur. HRRR guidance suggests 2 to 4 inches of
rainfall with isolated higher amounts is possible over southeast
Arkansas and northwest Mississippi through Friday afternoon.
HREF guidance is much less bullish on precipitation total, so
uncertainty remains too high to pull the trigger on a flash flood
watch at this time.
The main feature to watch tomorrow morning through Friday evening
will be a MCV that is expected to track slowly across central
Arkansas late tonight through Friday afternoon. As moisture surges
ahead of this mesoscale feature tomorrow, SBCAPE values could
climb to around 2000 J/kg in eastern Arkansas with up to 1000
J/kg into west Tennessee. With up to 35 knots of bulk shear, a few
mini supercells could develop by mid afternoon and could pose an
all-hazards risk. A Slight Risk remains in effect for areas west
of a north to south line from Blytheville, Arkansas to Bartlett,
Tennessee to Oxford, Mississippi.
A deepening positively-tilted shortwave will translate east
through central Arkansas with a weak surface low developing over
SEMO by Saturday morning. At the surface, an increasingly unstable
airmass will develop by Saturday morning and afternoon ahead of a
cold front. The ECMWF depicts the shortwave taking on a negative
tilt, which could push a QLCS through the region Saturday morning
or afternoon. The limiting factor for a higher end severe threat
will likely be the ongoing convection across the area Saturday
morning. Nonetheless, a Marginal Risk is in effect for severe
thunderstorms across the entire area. As hi-res model guidance
becomes available, a Slight Risk could be added as the convective
mode may become more clear. The cold front will push through the
region late Saturday night, briefly ending showers and
thunderstorms across the region.
Unsettled weather will continue Sunday through the long term
forecast as a series of weak shortwaves translate through nearly
zonal flow aloft. This will keep a medium chance of showers and
thunderstorms in the forecast each day through midweek. With the
increased clouds and showers across the region, temperatures
should remain near normal with highs in the mid 80s and lows in
the mid to upper 60s each day. A more organized system looks to
arrive by mid to late week as a large trough digs down across the
entire Mississippi Valley a pushes a cold front through the
region.
AC3
&&
.AVIATION...
(00Z TAFS)
Issued at 621 PM CDT Thu May 30 2024
The main focus this period will be timing of precipitation as
multiple rounds of showers and thunderstorms appear likely.
Thinking the initial wave of showers will not arrive until mid-
morning with TS chances increasing in the afternoon and evening.
CIGs should remain VFR with winds gusting to 20 kts by midday.
ANS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
PUBLIC FORECAST...SJM
AVIATION...ANS
Area Forecast Discussion
National Weather Service Pueblo CO
611 PM MDT Thu May 30 2024
.KEY MESSAGES...
- Scattered thunderstorms will continue through the evening, with a
few severe over the eastern plains. Main threat with severe storms
will be hail, possibly up to 2 inches in diameter, and strong
outflow winds up to 70 mph.
- Scattered thunderstorms will develop over the mountains
tomorrow afternoon (mainly over the eastern mountains) and
then move over the plains. A few could be strong to severe.
- Strong to severe storms will possible on Friday evening and again
Saturday afternoon/evening across southeast Colorado.
- Warmer and drier weather remains on tap for the end of the weekend
into at the middle of next week.
&&
.UPDATE...
Issued at 603 PM MDT Thu May 30 2024
Updated pops based on the latest radar trends. A line of
thunderstorms, some strong to severe, stretches southwest from
near Haswell, back to Timpas. Another cluster of storms is
moving across Huerfano County. The strongest cores will be
capable of producing hail of 1 to 2 inches in diameter, and
outflow wind gusts near 60 mph. These storms will continue to
track east impacting the Plains. The environment shows around
2500 j/kg of SBCAPE and 0-6km shear of around 30 kts. That
should be enough to sustain stronger cores through the evening
hours. Mozley
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 250 PM MDT Thu May 30 2024
Detailed discussion:
Currently and through tonight...
Latest CAMs continue to show progression of a developed MCS right
over the most southeastern corner of Colorado that expands
southeastward and forces back an outflow towards the northwest. This
will allow for an increase of low-level southeasterly flow and
moisture advection, with increasing dewpoints (approaching 60F in
some areas) extending up into the lower Arkansas River Valley by
later in the evening. At the same time, upsloping winds and a
conditionally unstable environment, which will help to initiate
convection over the Pikes Peak Region (PPR) and Ramparts, which will
move off towards the east with mid-level westerly winds in place.
This will eventually interact with the outflow boundary moving up
from the southeast to help intensify the convection as it continues
to move southeastward and over Kiowa County, or possibly further
south if the NAMNest verifies. The combination with the convergence
and conditionally unstable environment becoming more unstable as
will likely cause these storms to become severe. The only caveat is
that shear will be lacking where the brunt of the convection will
be, with better values further south over the far southeastern
plains, and also that there is currently a fair amount of CIN
(capping) which may inhibit intensification. The HRRR still has
storms merging into nearly a QLCS formation as they make their way
towards the CO/KS border. The NAMNest is similar, but further south.
If this comes to fruition, this will mainly become a strong wind
threat, basically from Eads to Lamar if the HRRR resolves this
better, and possibly have some landspouts occur. Although there are
some other high res guidance which suggests that some of these
storms will be more discrete. As the evening progresses, we will
continue to monitor the environment on SPC and determine if this
outflow and the timing will be efficient for further development and
the threat of severe thunderstorms over the far eastern plains.
Some of the storms will be capable of producing hail of possibly up
to 2 inches in diameter, as well as strong and gusty outflow winds
that could reach up to 70 mph, especially if storms merge and become
organized into a linear (QLCS) pattern. These storms will continue
to move off throughout the early morning hours tomorrow, and should
be clear of the CWA by around to 3 to 4 AM. From there, skies will
continue to clear, with temperatures dropping down into the low to
mid 50s across the plains, and generally in the 30s and 40s for high
country.
Tomorrow...
As the U/L trough remains to the north and keeps westerly mid-level
flow in place over the region, along with some recycled moisture and
orographic lifting, thunderstorms will develop again over the
mountains (mainly over the eastern mountains where there will be
better instability). With the steering flow, these storms will
eventually come off the mountains and over into the plains where
there will be better instability and shear, and have a possibility
of becoming severe again, especially as they continue to move
further to the east. That being said, overall there will not be as
much instability tomorrow as there was today, so perhaps the hail
will not be as large and wind gusts not as strong. It will also be
overall a little more stable on the plains with cooler temps, which
will be around 5 to 10 degrees cooler from where they were today.
-Stewey
&&
.LONG TERM /FRIDAY THROUGH THURSDAY/...
Issued at 250 PM MDT Thu May 30 2024
Friday night-Saturday night...West to southwest flow aloft remains
progged across the region as a shortwave trough translates across
across the Intermountain West and into the Northern Rockies by
Saturday night. The progged increased flow aloft (shear), combined
with enhanced low level moisture within south to southeast low level
return flow across the southeast Colorado Plains, will lead to the
potential for strong to severe storms across southeast Colorado
both Friday evening and again Saturday afternoon and evening.
Specifics on the amount on of instability and shear profiles will
depend on previous days convective debris and outflows, however,
SPC Day 2 and Day 3 outlooks still indicate a marginal to slight
risk of severe storms, producing large hail and damaging winds,
across most of eastern Colorado. Further west, some uvv ahead
of said wave could produce some high based -shra/-trsa west of
the Front Range, with main threats being gusty outflow winds, with
inverted v profiles.
Sunday-Monday...Moderate west to southwest flow across the region
Sunday becomes more northwest Sunday night into Monday, as shortwave
trough translates across the Northern Rockies and into the Upper
Midwest. Latest models continue to indicate a dryline pushing east
into western Kansas Sunday afternoon, with expected breezy and warm
westerly flow pushing into eastern Colorado, with highs pushing into
the mid 80s to mid 90s across the plains, and mainly 60s and 70s
across the higher terrain. Dry and breezy conditions will create
enhanced fire danger, however, current fuel status remains non
critical areawide. Passing wave send a week front across the area
Sunday night into Monday morning, however, temperatures to remain
generally above seasonal levels on Monday.
Tuesday-Thursday...While models differ on the timing of the upper level
ridging building across across the Rockies, generally warm and dry
conditions remain progged across the area into the middle of next
week.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 522 PM MDT Thu May 30 2024
KALS...VFR conditions through the next 24 hours. A few showers
and thunderstorms will be possible Friday afternoon and evening
across the San Luis Valley. The main concerns will be gusty
outflow winds at the terminal Friday afternoon.
KCOS and KPUB...a shower may be possible at KCOS this evening,
but confidence in occurrence is low. Otherwise, VFR conditions
will prevail at both terminals through much of the period.
Another round of showers and thunderstorms is forecast for
Friday afternoon and evening. KCOS looks to see the best chances
of seeing thunderstorms on Friday. Mozley
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...MOZLEY
SHORT TERM...STEWARD
LONG TERM...MW
AVIATION...MOZLEY
Area Forecast Discussion
National Weather Service Tulsa OK
920 PM CDT Thu May 30 2024
...New SHORT TERM...
.SHORT TERM...
(The rest of tonight)
Issued at 920 PM CDT Thu May 30 2024
The shortwave trough responsible for the line of convection this
morning/afternoon continues to slide eastward over the Ozarks and
central AR. Lingering light to moderate rain continues to fall,
mainly across far northeast OK and far northwest AR. Latest runs
of the CAMs show light-moderate precipitation persisting across
portions of northwest AR through much of the evening and overnight
hours. GOES-16 water vapor imagery shows another shortwave trough
moving out of the southern High Plains. The shortwave trough is
forecast to generate a thunderstorm complex that is expected to
move across southern OK/Red River vicinity overnight tonight and
through the early morning hours tomorrow. However, trends in hi-
res model data now indicate a southern shift in the thunderstorm
complex`s track from previous runs, with the latest HRRR run
suggesting the complex remains south of the Red River as it pushes
southeastward across northeast TX. Despite this occurring (or not
occurring), there should be sufficient lifting, moisture, and
instability to generate at least isolated to perhaps scattered
showers and thunderstorms across the entire forecast area as the
shortwave trough advances eastward tonight across OK. With PWATs
ranging between 1.5-1.75 inches across all of the area, more
organized showers and thunderstorms will produce heavy to very
heavy rainfall.
With all that said, for the evening forecast update, went ahead
and lowered PoPs area-wide tonight, especially before midnight.
For the sake of forecast consistency and some forecast
uncertainty, kept PoPs at 50-60% after midnight, highest chances
after 3 AM. The absolute best chance of heavy rain (and possibly
marginally severe thunderstorms) through the remainder of the
night and early morning hours will be associated with the
aforementioned thunderstorm complex, if it`s able to remain
along/north of the Red River. This would mostly affect Choctaw and
much of Pushmataha counties in OK. A Flood Watch remains in
effect for Choctaw County through Friday evening.
Mejia
&&
.LONG TERM...
(Tomorrow through Thursday)
Issued at 239 PM CDT Thu May 30 2024
Showers and storms are expected to expand in coverage Friday morning,
but will favor highest PoPs across SE OK and NW AR in the morning, and
begin to lower PoPs from W-E in the afternoon as the upper wave continues
pushing to the east. Rain/storm chances will continue to diminish Friday
evening an overnight. Subsidence behind the departing wave should allow
for most if not all of Saturday to remain dry. Will maintain low PoPs
for Sunday as another weak wave passes through. Active pattern to
continue the middle of the next work week. However, a stronger
upper system diving into the midwest states may finally push a
cold front through the area which would give the area a break from
the unsettled pattern we have been locked into.
&&
.AVIATION...
(00Z TAFS)
Issued at 645 PM CDT Thu May 30 2024
Periodic showers and a few thunderstorms will remain possible
through much of the forecast period, with KMLC and KFSM most
likely to see any significant impacts Friday morning. Ceilings
will lower to MVFR later tonight and remain MVFR, and possibly
even IFR at times, for the rest of the forecast period.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 79 65 76 63 / 50 60 70 30
FSM 84 68 77 67 / 60 70 70 50
MLC 79 65 78 64 / 30 50 80 40
BVO 79 63 75 60 / 50 60 70 30
FYV 82 64 76 62 / 40 80 80 50
BYV 80 63 73 63 / 10 60 80 60
MKO 80 66 75 63 / 60 60 70 50
MIO 82 64 72 62 / 70 80 80 50
F10 77 64 76 62 / 40 50 70 30
HHW 74 65 78 65 / 50 50 80 40
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Flood Watch through Friday evening for OKZ053.
AR...None.
&&
$$
SHORT TERM...67
LONG TERM....23
AVIATION...05