Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 06/12/23
Area Forecast Discussion
National Weather Service Fort Worth TX
534 PM CDT Sun Jun 11 2023
...New Short Term, Aviation...
.SHORT TERM... /NEW/
/This Evening through Monday Night/
Satellite imagery shows increasing low level convergence across
North Texas as the cumulus field has become a little more agitated
across the region. This area of convergence is focused along a
weak pre-frontal trough where temperatures have soared to near 100
degrees resulting in nearly 4000 J/kg of MUCAPE. An aircraft
sounding from DAL over the last hour still indicated some mixed
layer inhibition remaining, so this initial activity may struggle
a bit before thunderstorms begin to develop. Coverage through the
rest of the afternoon/evening will still be limited to around 30%
with most areas not being directly impacted by storms. Those that
do see storms will have the potential for large hail and damaging
winds. The tornado threat is low through this evening.
Storms should diminish in coverage with loss of heating this
evening, although a few of the CAMs keep things going until around
midnight or so, likely aided by stronger mid level flow and
forcing for ascent. Nonetheless, coverage should be low overnight.
The cold front to the north will sag south across the Red River
tonight and increasing ascent atop the shallow airmass could lead
to a few elevated showers/storms late tonight into early Monday
morning mainly along the Red River and in our northeast. We`ll
keep PoPs around 40-50% for this potential. The front will
continue to sag south toward the I-20 corridor Monday afternoon
and will again be a focus for vigorous storm development late in
the day.
Mid level flow will increase to around 60 kt by afternoon with
thunderstorms expected to develop and increase in coverage off to
our west/northwest near the surface triple point. This activity
will spread east into the evening hours and pose a severe threat,
however, given the increasing wind fields and proximity to an
east-west oriented surface boundary, there will be at least a low
tornado threat on Monday. Outside of this, strong surface based
instability will support a large hail/damaging wind threat into
the late evening hours. Coverage of storms should be a little
higher Monday afternoon/evening given stronger forcing for ascent
and a better defined zone of low level convergence. We`ll have
PoPs at 30-50% through the late evening hours.
Dunn
&&
.LONG TERM... /Issued 230 PM CDT Sun Jun 11 2023/
/Monday Night Onward/
North and Central Texas will remain in the active zone of a mid
level ridge currently centered over Mexico through at least mid
week. This region (in this case) lies beneath the northeast
periphery of the ridge, where weak disturbances aloft coincide
with intense surface heating to generate multiple rounds of
convection. Timing will be generally the same in each instance, in
the late afternoon and evening hours, but the exact locations may
vary each day.
Showers and thunderstorms will likely be ongoing Monday evening,
but should dissipate around midnight Monday night with the loss of
surface instability. A weak surface front will continue to
meander across the area on Tuesday as the next shortwave
disturbance rotates around the ridge. The front will provide the
surface focus for convective development by late Tuesday
afternoon. The exact location of the front is uncertain and may
depend on mesoscale processes from the previous evening. Ensemble
data and thunderstorm probabilities place the position of the
front and best storm chances along and near a line from Paris to
Sulphur Springs to Waco. The highest POPs at this time will fall
roughly along that axis, or primarily across the East Texas and
eastern Central Texas counties. This could change some in the
coming days as we fall into the range of higher resolution model
guidance.
It is extremely difficult to avoid sounding like a broken record,
but a similar set-up can be expected on Wednesday as the surface
front persists and the next shortwave rounds the ridge. Locations
along and east of I-35 will see the best storm chances, but with
low confidence in whether or not subsidence from the ridge will or
will not be strong enough to suppress convection will warrant
conservative POPs at this time.
The main story will shift to intense heat due to increasing
heights aloft, as the ridge expands northeast and begins to
dominate most of Texas and the Southern Plains. This process will
be somewhat gradual, taking place from late this week through
early next week. Triple digit high temperatures should become
common, initially across the western counties starting Thursday,
and expanding across the rest of the region Friday through the end
of the forecast period. Surface temperatures combined with the
dewpoint forecast indicates that heat advisory criteria could be
met for a good portion of the forecast area beginning Thursday or
Friday.
30
&&
.AVIATION... /NEW/
/00Z TAFs/
Main concern through this evening and again on Monday
afternoon/evening will be convective potential. We`ll continue
with VCTS this evening, although we`ll nudge the timing back to
00Z and continue through about 4Z. Outflow winds with any TS could
cause erratic wind shifts so we`ll continue to monitor this
potential. Otherwise, a cold front will sag south toward the I-20
corridor overnight with a north/northeast wind after midnight. In
addition, MVFR cigs will likely develop near and just behind the
frontal boundary Monday morning for a few hours. TS potential will
increase again mainly for the D10 airspace Monday afternoon into
the evening hours.
Dunn
&&
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 74 91 74 95 72 / 30 20 30 20 20
Waco 72 98 73 97 74 / 20 5 20 20 20
Paris 69 82 67 87 68 / 30 50 60 40 40
Denton 69 89 69 93 68 / 20 20 30 20 20
McKinney 70 87 70 91 69 / 20 20 40 30 20
Dallas 74 92 73 96 73 / 30 20 30 30 20
Terrell 71 90 71 91 71 / 30 20 30 30 40
Corsicana 74 94 74 93 73 / 30 10 20 20 30
Temple 72 97 73 98 73 / 10 5 10 10 20
Mineral Wells 71 94 71 96 68 / 30 30 30 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Louisville KY
858 PM EDT Sun Jun 11 2023
.Forecast Update...
Issued at 856 PM EDT Sun Jun 11 2023
Latest surface obs reveal low pressure centered roughly over
Cincinnati with the cold front extending SW along the OH River and
down to BWG. Current radar continues to show a widespread area of
rainfall with some embedded convection from the Bluegrass region
southward to Lake Cumberland while scattered showers along the
actual cold front are pushing through the I-65 corridor. As a
result, the Severe Thunderstorm Watch has been cancelled for our
CWA. Also removed mention of thunderstorms from weather grids
beginning at 12/02Z and made minor adjustments to near term grids.
Updated products forthcoming.
&&
.Short Term...(This evening through Monday)
Issued at 300 PM EDT Sun Jun 11 2023
...Damaging Thunderstorm Winds Possible This Afternoon/Evening...
Key Messages:
* Best chance of strong/severe storms between 3-8 PM EDT.
* Anywhere in the CWA is fair game, but most favorable in south
central Kentucky.
* Damaging winds are the main hazard, but locally heavy rain and
large hail are secondary threats.
* Thunderstorms also possible this morning, but will be non-severe.
Discussion: Thunderstorms have developed under and just ahead of a
compact upper level shortwave trough and sfc low over the Wabash. A
dry slot wrapping in ahead of this wave this morning and early
afternoon has allowed for partial sunshine with only SCT-BKN
stratocu. Temperatures responded into the upper 70s to lower 80s
with sfc dewpoints in the mid 60s to near 70 F in the warm sector.
However, the dry slot is beginning to close off now with the arrival
of deeper moisture and stronger forcing associated with the mid-
level shortwave trough.
MLCAPE will peak near 1500-2000 J/kg from now through 00z this
evening. Mid-level lapse rates are marginal, and recent SDF ACARS
soundings show a capping inversion near 800 mb. BNA ACARS soundings
show a weaker inversion just above 850 mb. This is perhaps why
initial updrafts have been a bit sluggish to develop vertically.
But the wave just upstream will maximize forcing and mid-level winds
now, through peak heating. The enhanced SW mid-level flow will
result in effective bulk shear of 25-30 kt. Scattered to numerous
multicellular clusters/segments will blossom this afternoon and
evening. Storms will push east across central KY and southern IN
into the evening hours, with the severe threat diminishing by 00z
due to waning instability.
Marginal deep and low-level shear continues to suggest a low tornado
risk, however cannot rule out a brief tornado should a bowing
segment become oriented perpendicular to the WSW 0-3 km shear vector.
The main threat continues to be damaging straight-line winds. Hail
and locally torrential rainfall are secondary threats. Large hail
should be isolated and limited to the strongest storms.
Convection diminishes in the Bluegrass and Lake Cumberland regions
by late this evening, though showery weather continues for the
eastern CWA into late tonight. Conditions gradually dry out from
west to east overnight as cooler, drier air advects in behind the
cold front. Temperatures dip into the 50s by daybreak Monday. A
closed upper level low continue to pivot southeast over the Great
Lakes on Monday. Stratus will likely persist through a lot of the
morning, with a clearing trend for the afternoon hours. Highs will
be cooler in the low to mid 70s.
.Long Term...(Monday night through Sunday)
Issued at 255 PM EDT Sun Jun 11 2023
The long term period will be characterized by an occluded upper low
over the Great Lakes, and a quasi-stationary boundary stretching
across the TN Valley through much of the week. A series of
disturbances will ride through the upper zonal flow over the Deep
South, resulting in daily low-end shower chances for Tue-Fri.
Dry weather is expected for most of the week, with any PoPs mainly
in the afternoon hours. Trend has continued to trim back PoPs each
day this week, with mainly 15-20% chances for those days mentioned.
On Tuesday, we look to be squeezed between the boundary to our south
and the upper low to our northeast, so may see some showers across
south-central KY and northern KY, but much of central KY should
remain dry. For Wednesday and Thursday, the upper low shifts a bit
further east, with shortwave energy focused more to our east. This
should result in better precip chances to our east each day, with
areas west of I-65 likely to remain dry. Temps will gradually creep
back up into the upper 80s as we progress through the week, though
Thursday should be the warmest day of the period with highs in the
upper 80s, possibly near 90 in urban islands.
Daily shower and storm chances continue into the weekend, especially
for Saturday as the boundary across the TN Valley surges northward
finally into KY. This results in board brush PoPs for much of the
weekend, with temps in the mid 80s each afternoon.
&&
.Aviation...(00Z TAF Issuance)
Issued at 150 PM EDT Sun Jun 11 2023
Impacts:
- Thunderstorms ending early in TAF cycle at LEX
- CIGs decreasing to MVFR/IFR overnight
- VFR conditions returning Monday late morning/early afternoon
Discussion:
Latest surface analysis places the low center near the
tri-state border of IN/KY/OH with a cold front extending SSW through
western KY. Current radar continues to show a line of storms
oriented NE-SW through central KY, which will pushing into the LEX
area within the next hour. Expect MVFR CIGs to advect in behind the
cold front with most locations experiencing IFR CIGs overnight. Low
stratus will persist through Monday morning before breaking up by
early afternoon. Winds will veer to NW behind the front as well,
with some gusts around 20kts. Winds will calm down Monday afternoon
with the return of VFR conditions.
Confidence:
- High confidence on MVFR/IFR CIGs
- Medium confidence on timing of VFR conditions
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&
$$
Update...CG
Short Term...EBW
Long Term...CJP
Aviation...CG