Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/06/23
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
559 PM CDT Fri May 5 2023
...New AVIATION...
.SHORT TERM...
(Tonight through Saturday night)
Issued at 220 PM CDT Fri May 5 2023
All eyes and focus remains on convective initiation across the
Rio Grande this afternoon. The Storm Prediction Center has kept
portions of Deep South Texas west of I-69C in a Marginal Risk of
severe thunderstorms this afternoon and tonight. Latest convective
allowing model runs seem to agree on general location and timing
of storm initiation (northern Nuevo Leon/Tamaulipas by mid-late
afternoon) but continue to differ on the E/SE progression of the
storms. Latest forecast soundings from around Zapata/Starr
counties indicate a fairly stable boundary layer in place, though
some destabilization occurs a few hours before 00z/7 PM. However,
wind speeds below 700mb are fairly weak and are not very
supportive to sustain any thunderstorms that are already ongoing.
Nevertheless, organized storms that are able to cross the Rio
Grande will be capable of tapping into a significant amount of
CAPE (as well as bulk shear and steep mid-level lapse rates) and
will be capable of producing large hail (>= 1") and damaging wind
gusts (in excess of 60 mph). Most CAMs show storms quickly eroding
and dissipating by sunset this evening, with a couple of CAM
outliers indicating storms keeping their energy and pushing east
of the I-69C corridor. Not anticipating that extent of eastward
progression at this time, but will monitor. Residents living along
the Rio Grande in Zapata and Starr counties will need to keep
vigilant over the next few hours.
Otherwise, mid-level ridging will maintain warm, humid, breezy, and
hazy conditions through Saturday night. Skies become mostly cloudy
again tonight but clouds should scatter out mid-late Saturday
morning. Anticipate overnight low temperatures only reaching the mid-
70 next couple of nights, while daytime highs on Saturday will soar
into the mid-upper 90s for most locations (perhaps touching 100
degrees near and around Falcon Lake). With a very humid air mass in
place, heat index values will approach 110 degrees across Zapata,
Jim Hogg, Starr and western Hidalgo counties for a few hours during
&&
.LONG TERM...
(Sunday through next Friday)
Issued at 220 PM CDT Fri May 5 2023
The start of the long term forecast on Sunday through most of Monday
is dry for Deep South Texas. However rain chances will start to pick
up on Tuesday and for the rest of the long term period as a 500 mb
high pressure moves away as an upper level low moves over the Pacific
northwest. This will put Deep South Texas into a southwesterly flow
pattern and allow for a series of mid-level disturbances to pass
over the region. There is the potential for some of these storms to
be strong to severe thus monitoring how future model runs handles
the development of the the convection will be important.
The winds are expected to be out of the southeast for the long term
forecast from Sunday through next Friday. This will help bring in
moisture that will be needed for the development of any showers are
thunderstorms. Another consequence of this will be in the hotter
temperatures that will be present in the area. Low temperatures will
be generally in the 70s, while the high temperatures will be in the
range of upper 80s along the coast and beaches, and in the 90s for
the rest of Deep South Texas.
&&
.AVIATION...
(00Z TAFS)
Issued at 552 PM CDT Fri May 5 2023
Convection is firing along the front range of the Sierra Madre
Oriental in Mexico, mainly approaching the Upper Valley/Rio Grande
Plains. The HRRR captures this activity, with most of it dying
off in another three or four hours. That said, MVFR ceilings will
develop after midnight with patchy light fog possible in spots
around dawn, though winds will be a bit too strong for more than
that. Ceilings will lift Saturday afternoon as breezy southeast
winds develop.
&&
.MARINE...
Issued at 220 PM CDT Fri May 5 2023
Now through Saturday Night...Light-to-moderate SE winds and Gulf
seas of 2-4 ft will make for favorable boating conditions through
the first half of the weekend. Winds pick up and become breezy on
the Laguna Madre Saturday afternoon and Small Craft Exercise Caution
conditions are possible through sunset Saturday. Otherwise, marine
conditions remain mostly benign.
Sunday through Next Friday...Southeasterly winds will persist
Sunday through next Friday. Winds at times could be moderate and
rough seas are possible so that Small Craft Exercise Caution will
be required due to a slightly enhanced pressure gradient over the
western Gulf of Mexico. There is a possibility that a low end
Small Craft Advisory might as also be needed based on the winds.
&&
.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE 76 92 76 88 / 10 0 0 0
HARLINGEN 74 94 74 93 / 10 0 0 0
MCALLEN 76 94 76 94 / 20 0 0 0
RIO GRANDE CITY 74 99 75 97 / 20 0 0 10
SOUTH PADRE ISLAND 75 85 76 82 / 10 0 0 0
BAYVIEW/PORT ISABEL 74 89 74 88 / 10 0 0 0
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
SHORT TERM...54-BHM
LONG TERM....69-Farris
AVIATION...54-BHM
Area Forecast Discussion
National Weather Service Columbia SC
1046 PM EDT Fri May 5 2023
.SYNOPSIS...
A weak front will lift north into the area, then generally stall
and dissipate into the weekend, bringing with it mainly isolated
to scattered light showers through Saturday. Atlantic high
pressure will then build into the region during the early to
middle part of next week, with temperatures expected to be well
above normal and a chance of daily afternoon and evening
showers and thunderstorms. Cooler and drier conditions expected
by Thursday following the passage of a cold front.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Moisture advection over a ridge to our west has resulted in
mid-level clouds streaming into the forecast area. Radar shows
light returns from these SE moving, mid-level clouds located
over the southern half of the forecast area. However low-level
dry air will largely prevent rainfall from reaching the ground.
As the low levels moisten overnight measurable rainfall will
become a little more likely. A shortwave will also move into
the area late tonight helping to support showers. CAMs suggest
the sprinkles will spread northward into the central Midlands as
the ridge axis shifts further east. Temperatures tonight will
be in the 50s due to cloud cover.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
Upper level ridge will shift east over the Mississippi Valley on
Saturday, maintaining the northwest flow aloft across the
region. Diffuse front stalled over the area should dissipate,
but short wave energy aloft, and moist mid levels of the
atmosphere should support mainly isolated light showers across
much of the area during the day. The cloud cover will aid in
keeping temperatures somewhat below normal, with highs in the
mid to upper 70s.
Atlantic high pressure will establish a southerly flow across
the area on Sunday. Isolated convection is certainly possible
given suitable moisture in the lower and mid levels of the
atmosphere, but model guidance has backed off on coverage quite
a bit. The southerly flow will allow for warmer temperatures,
but cloud cover will limit overall heating with highs in the
lower 80s. Temperatures Sunday night will be more mild, with
lows in the lower to mid 60s.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
Ensembles indicate the upper ridge shifting eastward, resulting
in a continued warming trend into mid-week with above normal
temperatures. A series of short wave disturbances, a
sufficiently moist atmosphere and diurnal heating will support
scattered showers and thunderstorms, especially each afternoon
and evening through Wednesday. A cold front will pass through
Wednesday, with cooler and drier conditions expected by
Thursday.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
An upper disturbance crossing the region with adequate moisture
in place is result in some light showers impacting AGS/DNL while
staying mainly south of CAE/CUB/OGB. Forcing is generally weak
and low level dry air in place is preventing any cig/vis
restrictions associated with light showers. Overall moisture
should gradually increase some overnight but model time heights
showing cigs should remain VFR through much of the period.
NBM and HRRR showing some MVFR cigs developing over central GA
during the predawn hours and possibly spreading northeastward
into the CSRA and hinting at possible MVFR cig restrictions
after 12z AGS/DNL. Given increasing low level moisture decided
to go ahead and carry MVFR cigs AGS/DNL after 13z. Fog is
possible at prone AGS/OGB but given extensive cloud cover
overnight do not think it is likely and therefore have not
included at this time. Winds will be light and variable to calm
overnight before picking up from the southeast to south after
15z Saturday.
EXTENDED AVIATION OUTLOOK...Chance of MVFR CIG restrictions
possible Sat/Sat night into Sunday morning. Scattered convection
possible in the afternoon Mon/Tue.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
Area Forecast Discussion
National Weather Service Cheyenne WY
529 PM MDT Fri May 5 2023
.SHORT TERM...(This evening through Saturday night)
Issued at 231 PM MDT Fri May 5 2023
KEY MESSAGES:
1) Marginal to Slight Risk in effect through this evening for the
severe thunderstorm threat across portions of eastern Wyoming and
the Nebraksa panhandle. Primary hazards will include lightning,
strong winds, and potentially large hail.
2) Thunderstorm chances are more isolated tomorrow with the best
chances at higher elevations with snow showers in the mountains.
3) Temperatures will be a few degrees cooler Saturday with high
temperatures in the 60s to low 70s and lows in the 30s to 40s.
DISCUSSION: Thunderstorm initiation has begun across far southeast
Wyoming and the southern Nebraska panhandle where a moisture
convergence boundary has set up. In addition, there is a line of
discrete cells firing up along a line from near Bill, WY to
Alliance, NE where a stationary front is currently positioned. The
primary limiting factor for the thunderstorms at the moment is the
lack of shear. Due to this, the storms are quite "pulsey" at the
moment. The RAP is showing better shear values coming into play
later this evening as the LLJ develops, increasing flow aloft,
mainly across the Nebraska panhandle this evening. Unfortunately, as
the better shear values begin to come into play, the instability is
not as potent due to it being well past peak daytime heating.
However, if the discrete cells do form into a line as many HiRes
models are showing, the increased shear will help sustain them
into overnight hours.
Tomorrow, much drier air moves into place at lower and mid-levels,
and as the trough shift eastward, so does the better moisture and
instability. The best chance for thunderstorms will be in higher
elevations and in the mountains. Any thunderstorms that do develop
and move off the higher terrain will likely be high-based and will
not produce much, if any rainfall.
There is also a marginal High Wind threat, primarily in wind-prone
areas of southeast Wyoming (Arlington and Bordeaux) with strong
westerly winds and subsidence in place. West wind gusts 40 to 50 mph
are possible in the afternoon, mainly between noon and 6 pm.
.LONG TERM...(Sunday through Friday)
Issued at 231 PM MDT Fri May 5 2023
Medium to long range models continue to show a rather unsettled
weather pattern for most of next week with maybe a brief lull in
thunderstorm activity earlier in the week around Monday.
All models show generally the same pattern with the Omega Block
over central Canada gradually breaking down with a train of storm
systems moving out of the Pacific undercutting the broad ridge. West
to southwest flow aloft is expected for the central Rocky and
adjacent high plains as these Pacific storm systems move northeast
across the Great Basin Region and into the northern Rocky Mountain
Region. Several upper level disturbances will push across the forecast
area every 18 to 24 hours, the strongest of which looks to be arriving
on Tuesday. In addition, an active jet stream will remain nearly
stationary over the forecast area and near the Colorado/Wyoming border
Sunday through Wednesday, with individual jet streaks embedded in the
mean flow aloft. With areas of enhanced upper level difluent flow,
could see a more widespread coverage of thunderstorms than current
models suggest. May see an area of more organized convection/squall
lines east of the Wyoming border later on Tuesday due to moist
southerly flow and a potent low level jet developing Tuesday night.
Kept POP on the high side and higher than most guidance, especially
across southeast Wyoming and southern Nebraska. Kept high temperatures
near or slightly above average for this time of the year and generally
in the 60s to mid 70s for most areas. Morning lows will be seasonably
cool, but around average.
By late wednesday through the end of next week, models continue to
hint to a cooler and much wetter pattern as a stronger Pacific
storm moves onshore along California and ejects east over the
western United States or the Great Basin region. Models are having
trouble placing where this storm will track. The GFS is more
progressive and further north, but shows the storm stalling and
then gradually retrograding west by the end of the week, resulting
in prolonged rainfall and mountain snowfall along with cooler than
normal temperatures. The ECMWF, Canadian, and around half the
ECMWF and GEFS ensemble members show a warmer, but considerably
wetter pattern as the storm system stalls near the four corners
region on Thursday. Will have to monitor this potential over the
next several days with plentiful moisture in easterly flow and
excellent dynamic lift for this time of the year. With 700mb
temperatures between 1c to 5c, hydro concerns are possible due to
mountain rainfall. However, if the GFS verifies there will be
plenty of colder air for snow above 8000 feet. Regardless of which
scenario verifies, it looks pretty wet for the eastern plains.
Stay tuned.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 521 PM MDT Fri May 5 2023
Wyoming TAFS...A passing weather disturbance will produce isolated
thunderstorms in the vicinity at Laramie and Cheyenne until 02Z.
Otherwise, scattered clouds from 8000 to 10000 feet AGL will
prevail. Decent surface pressure gradients will produce wind gusts
to 35 knots at all terminals until 02Z, and to 30 knots after
14Z Saturday.
Nebraska TAFS...A passing weather disturbance will help produce
scattered thunderstorms producing localized MVFR ceilings and
visibilities until 03Z, with winds gusting up to 45 knots near
storms. With conditions becoming more saturated overnight, expect
IFR ceilings under 1000 feet at Chadron and Alliance from 06Z to
13Z. Elsewhere, scattered to broken clouds from 8000 to 10000 feet
AGL will exist, with scattered clouds around 10000 feet AGL at
all terminals after 15Z Saturday. Surface pressure gradients will
be sufficient to produce wind gusts to 27 knots until 03Z, and to
30 knots after 15Z Saturday.
&&
.FIRE WEATHER...
Issued at 231 PM MDT Fri May 5 2023
Minimal fire weather concerns over the next week as southeast
Wyoming and Nebraska Panhandle experiences daily chances for
showers and thunderstorms. A slow moving low pressure system over
Utah will continue to bring moisture north into the area. This
southwest flow continues through much of next week with daily
chances for wetting rains. Afternoon humidity stays well above
critical levels with fair to good overnight recoveries.
&&
.HYDROLOGY...
Issued at 231 PM MDT Fri May 5 2023
Areal Flood Warning remains in effect for southwest Carbon Co
mainly concerning areas around the Little Snake River near Baggs until
9 PM today. Slightly above average temperatures will continue
today and this weekend, but will not be 10-15F degrees above
average like earlier this week that led to rapid meltoff and
rising river levels. Latest hydrographs observations at Baggs and
Savery both show overnight minimums in river stages equivalent to
those observed last night. This is promising, suggesting that
daily crests should not exceed previous day`s stages. Regardless,
minor flood stage still looks achievable today and therefore will
need to monitor river observations before deciding to
cancel/extend the flood warning beyond midday today. Most
convection today should remain east of the Laramie Range and
therefore should not have compounding effects with rain on snow
not expected.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
SHORT TERM...LK
LONG TERM...TJT
AVIATION...RUBIN
FIRE WEATHER...GCC
HYDROLOGY...MB
Area Forecast Discussion
National Weather Service Goodland KS
634 PM MDT Fri May 5 2023
.SHORT TERM...(This evening through Sunday evening)
Issued at 218 PM MDT Fri May 5 2023
The main concern for today will be the severe weather potential
across the area. Synoptically, a trough is ejecting out of the
southern Rockies. At the surface two surface lows are seen across
east Colorado with the northern most one roughly around Morgan
county and the southern located near Prowers county. Surface
analysis does show a dry line roughly across the Palmer Divide and a
pseudo warm front draped across roughly Interstate 70. Overall
CAMS have been indifferent on how convection does pan out for
today. The HRRR keeps the bulk of the severe storms in Nebraska
whereas the NAMNEST does fire discrete supercells off the dryline.
Forecast soundings are favorable for 2 inch hail as the primary
threat with MUCAPE greater than 2000 j/kg, effective bulk wind
difference around 50 knots and steep mid level lapse rates around
8.5C. Severe storm initiation is expected around 21-22Z around the
Goodland area before storms move to the NNE. Bunkers Storm motion
with an left movers to the NNE around 20-30 mph and any right
moving cells moving easterly at 10-15 mph. RAP hodographs do show
straight line hodographs would would support cell interactions, if
this could occur along a boundary then support a conditional
tornado threat. With this initial round if a tornado where to
happen it would across the northeast portion of the area roughly
Decatur, Norton, Red Willow, Hitchcock counties.
There is the potential for a second round of storms with an
advancing cold front from the west. CAMS have been in relatively
decent agreement with this occurring. RAP soundings do suggest
that severe weather could be possibility with this round of
storms as well with hail up to ping pong ball size, damaging
winds, and perhaps the potential for a quick QLCS spin-up tornado
as the LLJ increases and elongates hodographs. This round of
potential severe weather looks to begin around 9pm MT near the
Kansas/Colorado border and then move east. Any severe potential is
forecasted to be out of the area around midnight MT. Low
temperatures are forecast to fall into the low 40s to the mid 50s
across the area. Guidance has been suggesting at fog/low stratus
working around the low from the northeast so did introduce patchy
fog into the forecast.
Saturday, the longwave trough continues synoptically, with the
relative more moist air mass moving to the east.Winds will be
relatively light for High Plains standards around 10 mph over the
majority of the area. Across east Colorado another surface low
develops during the afternoon which will allow winds to become a
bit more breezy around 15-20 mph. The over flow isn`t the greatest
around 15-20 knots, however inverted v soundings in place along
with some pressure falls should help mix some near 30 knot winds
to the surface during the afternoon hours. The Fire Weather Watch
has been upgraded to a Red Flag Warning for Cheyenne and Kit
Carson counties in Colorado due to RH values falling into the low
teens and the potential for wind gusts of 30-35 mph at times. A
slight chance of showers and storms does exist across western Yuma
County during the late afternoon hours. Severe weather does not
look likely at this time. High temperatures are forecast to be in
the mid 80s to the east and mid 70s to the west.
Sunday will see the warm temperatures continue in the upper 80s
to the east and mid to upper 70s to the west. A surface low is
forecast to be over the area which should help keep winds around
10-15 mph despite RH values falling into the low teens again. As a
result of the lighter winds fire weather currently does not look
to be a concern. A few showers and storms are again possible north
of I-70 but is dependent on the exact position of the surface
low.
.LONG TERM...(Sunday night through Friday)
Issued at 130 PM MDT Fri May 5 2023
Trough in the western CONUS Monday and Tuesday will continue the
southwest flow over the central plains. Precipitation chances will
be limited on Monday due to overall lack of instability, but by
Tuesday do see some decent low level moisture back into the area
and moderate instability is currently forecast. Coupled with deep
layer shear of around 50 kts severe storms will be possible on
Tuesday. Temperatures continue above normal. Relative humidity
does drop below 20 percent in western areas on Monday, but winds
are forecast to be light, mitigating fire weather concerns.
For the period Wednesday through Friday...strength and track of
the western trough is not being handled very consistently by the
models, with even more differences compared to previous runs.
The GFS lifts it into the northern plains, a track which would dry
slot the area for a couple of days, then digs a trough into the
plains by Friday which would bring back precipitation chances.
However, the ECMWF stalls the system as an upper low near the Four
Corners which ultimately dissipates under the building western
ridge. The ECMWF would bring better chances for precipitation
Thursday and Friday with vorticity lobes rotating around the
closed low. The solutions are radically different and do not have
much confidence in either one at this time. Persistence forecast
would keep daily POPs going and just a slight cool down in
temperatures but still above normal.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 600 PM MDT Fri May 5 2023
GLD: Adverse aviation conditions associated with isolated
thunderstorms are possible later this evening.. mainly in the
03-07Z time frame. Confidence is low with regard to whether or not
thunderstorms will develop. MVFR-IFR conditions associated with
fog and/or stratus are possible for a few hours on either side of
sunrise Saturday morning, though, yet again.. confidence is well
below average. Otherwise, VFR conditions will prevail. Breezy
(15-25 knot) SSE winds will become light/variable by ~03Z this
evening.. as a weak lee cyclone progresses eastward over northwest
KS. Winds will shift to the N by ~09Z.. as the aforementioned lee
cyclone progresses eastward into central KS. Light/variable winds
are anticipated to prevail thereafter, through the remainder of
the TAF period.
MCK: Adverse aviation conditions associated with isolated
thunderstorms are possible later this evening.. mainly in the
03-07Z time frame. Confidence is low with regard to whether or not
thunderstorms will develop. MVFR-IFR conditions associated with
fog and/or stratus are possible for a few hours on either side of
sunrise Saturday morning, though.. confidence is below average.
Otherwise, VFR conditions will prevail. 10-15 knot E winds will
shift to the NE by ~03Z this evening as a weak lee cyclone
progresses eastward into northwest KS. Winds may become variable
for a period thereafter, shifting to the N by ~09Z.. as the
aforementioned lee cyclone progresses eastward into central KS.
Winds will become variable again after sunrise.. persisting
through the remainder of the TAF period.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NE...NONE.
&&
$$
SHORT TERM...Trigg
LONG TERM...024
AVIATION...Vincent
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
946 PM EDT Fri May 5 2023
.SYNOPSIS...
Rain chances return late today into Saturday with the arrival of a
warm front. A late-spring or early-summer like weather pattern will
develop over the area early next week, with temperatures trending
warmer and daily chances for showers and thunderstorms uptick.
&&
.NEAR TERM /THROUGH SATURDAY/...
As of 940 PM Friday: A band of light showers across northeast
Georgia continues to dissipate as already nebulous forcing lifts
away from the area. A few isolated showers may linger through the
overnight across the far western portions of the CWA, but most
locations will remain dry. High clouds will stream across the region
with overnight lows in the upper 40s to mid 50s. The ongoing
forecast remains on track and only minor adjustments to PoPs were
needed.
Upper-level ridging will gradually build across the central and
southern CONUS while mid-level shortwaves track overhead the western
Carolinas and northeast Georgia through the near term fcst period.
At the sfc, high pressure will sink southward out of eastern Canada
into the eastern CONUS through the period. This pattern will mostly
act to shunt rain chances well to our west and south this afternoon.
However, this evening into Saturday morning, both CAMs and global
models show rain chances increasing across the western half of the
CWA. Since models have generally been trending lower in regards to
rain chances the last several model runs, went ahead and lowered
PoPs to chance across the western zones through Saturday afternoon.
Also removed any thunder potential as instability looks to be fairly
limited. Guidance has also been trending lower on cloud cover this
afternoon, especially across the northern zones. Current visible
satellite loops show mostly sunny skies, along with some fair wx cu,
across the northern half of the CWA. Cloud cover looks to remain
limited over these same areas overnight into Saturday. Upper cloud
cover hangs around elsewhere today into tonight, with low to mid-
level clouds increasing on Saturday. Highs today will be similar to
yesterday`s and around 2-5 degrees below climo. Lows tonight should
be near to a few degrees above climo thanks to upper-level cloud
cover. Highs on Saturday will be around 3-7 degrees below climo
across the western zones where mostly cloudy skies are expected.
Highs will be around 1-3 degrees below climo across the NC Piedmont
and northern NC Foothills where cloud cover will be less extensive.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
As of 130 PM EDT Friday: Upper-level ridge over the MS Valley will
slowly encroach the region during the forecast period, but begins
to break down in the process. Clusters of vort lobes will ride
within the peripheral of the ridge and sink downstream on the
lee-side of the ridge. Better moisture advection will filter into
the from the southwest Saturday night into Sunday as the surface
high slips offshore the Southeast Coast. A new development from
the HRRR shows a decaying MCS feature running with the alluded
vort lobe and scraping the western fringe of the CFWA overnight
Saturday. In this case, the temperature forecast for Sunday could
become tricky as lingering convective debris could keep highs
from reaching its full potential, especially across the Upper
Savannah. Otherwise, PWATs will rise (1.00"-1.50") on Sunday as
low-level southwesterly flow becomes better established. The upper
ridge will breakdown with continuous vort lobes riding within the
northwesterly flow aloft. Model guidance show the potential for
more MCS-like features developing across the OH-Valley on Sunday,
but with higher heights in place over the CFWA, expect the warmer
air aloft to help keep most activity capped, with the exception
of a few isolated upslope showers/storms in the NC mountains,
with a small chance of this activity breaking containment outside
of the mountains. Temperatures should begin the recovery process
on Sunday with values climbing back to near-normal.
An unsettled pattern begins to take place Sunday night,
especially by Monday as the ridge breaks down even more and
vigorous shortwaves traverses across the CFWA. MCS-like features
will drift within these areas of vort energy as they continue to
reside within the west-northwesterly flow aloft and allow for an
uptick in PoPs/convection. With an increase in moisture, warmth, and
instability, thunder probabilities will be situated in the forecast
through the end of the short-term. The overall severe threat is
low, but definitely nonzero, with isolated straight-line damaging
gusts being the main impact if anything arises. Temperatures will
increase another category or two on Monday compared to Sunday.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 215 PM EDT Friday: Upper-level flow gradually becomes
quasi-zonal as the ridge breaks down across the eastern-third of
the CONUS. Vigorous shortwaves will continue to ripple through the
west-northwest flow aloft Tuesday and Wednesday as the surface high
shifts further offshore into the western Atlantic. Moisture will
be maximized through Wednesday before a back door cold front sinks
south through the CFWA by Wednesday night. Ahead of this boundary,
expect temperatures to remain 5-10 degrees above normal, with
unsettled weather continuing. As the front approaches Wednesday,
shear parameters uptick, which could lead to a better environment
for more organized and stronger storms. The forecast is still
pretty far out, but a trend worth watching. The back door boundary
should slip well south of the CFWA by Thursday and allow for drier
air to settle in. Model guidance place a surface high over the
Northeast/Mid-Atlantic behind the front. A short-lived wedge-like
configuration could settle over the region as a result. At the same
time, thicknesses will become elevated as an upper ridge sets up
shop over the eastern-third of the CONUS by the end of the work
week. This should help offset temperatures and allow for values
to be near-normal despite the potential for a cool wedge during
this time.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: VFR conditions will continue to prevail at
all terminals through the TAF period. Showers will remain confined
to northeast Georgia with a brief shower possible at KAND this
evening. Otherwise, high clouds will stream across the region and
eventually lower but remain VFR. An MVFR stratus deck will likely
edge into northeast Georgia early tomorrow morning, but confidence
is low with regards to how far north it makes it. Winds will be
light to calm overnight and will remain light out of the
south/southwest tomorrow.
Outlook: Episodic showers and thunderstorms can be expected Sunday
into early next week which could bring temporary restrictions to
area terminals.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
SYNOPSIS...CAC
NEAR TERM...AR/TW
SHORT TERM...CAC
LONG TERM...CAC
AVIATION...TW
Area Forecast Discussion
National Weather Service Wichita KS
710 PM CDT Fri May 5 2023
.SHORT TERM...(This evening through Sunday night)
Issued at 234 PM CDT Fri May 5 2023
Lingering low level moisture has led to some stubborn low cloudiness
lingering over southern KS for the afternoon hours. Latest SREF
seems to have the best handle on the cloud cover, with the cloud
cover expected to slowly erode for the evening hours, but slowly
returning across central KS late tonight as SW flow and warm
advection increases across the region. Latest RAP shows low level
moisture transport increasing out of OK into portions of central KS
by early on Sat morning, which may lead to a stray shower/storm
across NE KS, possibly along the NE fringes of the forecast area.
Will keep any shower/storm mention out of the forecast for now, but
given increasing warm air aloft, chances look slim. If any activity
develops it will quickly lift NE into NE KS and SE Neb by sunrise
Sat.
The stout warm advection with a SW downslope component will lead to
a warming trend for the weekend. Latest 1000-850H partial thickness
values suggest max temperatures will climb into the lower 90s for
Sat and possibly into the mid 90s for Sunday. Given the dry
antecedent conditions and the lack of rainfall, max temperatures may
even go slightly higher than we are currently forecasting. NAM/WRF
suggests max temps in the middle to upper 90s. For now will go with
model consensus and keep temps in the middle 90s for Sunday.
With the warm air, comes drier air for most locations for Sat and
again on Sun. A dry line looks to push across the forecast area on
Sunday, and be situated over SE by Sun afternoon, but a warm
elevated mixed layer (cap) will probably preclude any shower/storm
development for Sunday afternoon for SE KS. If the cap can erode
enough for convection to develop, an isolated strong/severe storm
may occur, given moderate instability, decent directional shear but
marginal shear. Plan on keeping a low pop in for this chance. Latest
consensus forecast shows chance pops for most locations for Sunday
night, but a warm elevated mixed layer will probably keep most
locations dry, with better chances further south across OK. Will
maintain a chance pop for now, but expect changes to this time
frame.
Ketcham
.LONG TERM...(Monday through Friday)
Issued at 234 PM CDT Fri May 5 2023
Lots of uncertainty on how the beginning of the week will unfold, as
weak SW flow continues across the area, with a series of weak
disturbances moving across the area. After a dry day on Mon,
shower/storm chances look to increase for Tue through Thu. Latest
deterministic models suggest "hit or miss" evening and nighttime
chances of showers/storms, with the most likely chance of seeing
widespread showers/storms being Tue night and again on Thu night, as
a cold front stalls over central KS, with chances in the warm sector
south of the boundary.
Ketcham
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 638 PM CDT Fri May 5 2023
MVFR cigs have finally mixed out across south central Kansas but
this may be short-lived as low cigs try to redevelop between
03-09Z across much of the area before mixing east and
northeastward thereafter. A transient shower or storm may impact
portions of south central or southeast KS tonight as some low
level moisture transport/isentropic upglide develop over the area
but better chances are expected to remain north and east of our
forecast area impacting northeast KS. A trough of low pressure
will move into central KS on Sat allowing westerly and
southwesterly winds to impact the region on Sat afternoon. Any
lingering low cigs across southeast KS early Sat are expected to
mix out by 16Z with VFR prevailing thereafter.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 60 91 62 94 / 0 0 0 10
Hutchinson 58 91 59 93 / 10 0 0 10
Newton 61 91 62 93 / 10 0 0 10
ElDorado 61 91 63 92 / 10 0 10 20
Winfield-KWLD 61 92 63 93 / 0 0 10 10
Russell 58 89 54 91 / 10 0 10 0
Great Bend 56 89 54 91 / 10 0 0 0
Salina 61 91 60 93 / 10 0 10 10
McPherson 60 90 59 93 / 10 0 0 10
Coffeyville 63 89 67 90 / 0 10 10 20
Chanute 63 90 67 91 / 10 0 10 20
Iola 62 89 66 91 / 10 10 10 30
Parsons-KPPF 63 89 67 91 / 10 0 10 20
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Ketcham
LONG TERM...Ketcham
AVIATION...MWM
Area Forecast Discussion
National Weather Service Wilmington NC
712 PM EDT Fri May 5 2023
.SYNOPSIS...
Forecast looks to stay mostly dry through early Sunday, with
temperatures near or just below normal. Warming trend kicks off
Sunday, with a chance of showers and thunderstorms Monday and
Tuesday. By midweek, a weak cold front sinks southward, bringing
a subtle cooling and drying trend.
&&
.UPDATE...
Minor changes to the hourly temperatures, otherwise forecast is
on track.
&&
.NEAR TERM /THROUGH SATURDAY/...
Weak high pressure will reside across the area under a
northwest flow aloft through Saturday. Any mention of pops have
been removed from the forecast via the guidance trends. Taking a
look at satellite imagery, the shortwave across Texas just
isn`t impressive from a moisture standpoint and the dry air over
our area is seemingly going to prevail. Still a lot of mid and
high level cloud cover to move across from time to time however.
Regarding temperatures, the cooler guidance has been the
preferred numbers for lows although more cloud cover tonight may
skew this bias but overall expect middle 50s or so. Saturday`s
highs will be similar to today somewhat modulated by the cloud
cover.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
While high pressure at the surface will be offshore Saturday
night through Sunday night, mid level ridge lingers over the
Southeast during the short term period. Therefore subsidence
inversion around 700mb persists through Sunday. Have lowered
pops quite a bit for Sunday afternoon and capped at 20%. May see
isolated convection along sea breeze or with diurnal heating
with low level return flow, but will be tough for more than a
couple of storms to develop. Surface trough passing to the north
Sunday night may bring some showers to northern parts of the
CWA, with pops again fairly low. Low temps Saturday night in the
upper 50s with highs in the low 80s away from the coast Sunday.
Bit warmer in the low 60s Sunday night.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
Mid and upper level ridges flatten out for start of next week,
leading to several shortwaves moving across the area Monday into
Tuesday. Both days will feature above normal temps in the upper
80s, approaching 90F. Monday looks to be a good day for typical
diurnal and sea breeze convection, with sufficient instability
and plenty of sunshine. Bit more cloud cloud cover Monday night
into Tuesday from a stronger shortwave, though some clearing
will allow Tuesday to be another scattered storm day. A weak
cold front drops south Tuesday night, with slow movement south
of the area Wednesday into Thursday. Dry air mass with a brief
high pressure wedge Wednesday and Thursday will drop temps to
near normal. Only rain chance for back half of the week is
Wednesday afternoon, where I kept in low pops along sea breeze
to account for dry air and subsidence timing. High pressure
shifts offshore end of next week with weak onshore flow
returning.
&&
.AVIATION /00Z FRIDAY THROUGH WEDNESDAY/...
VFR conditions are expected through 00 UTC Sunday. Only concern
is a small smoldering fire from a lighting strike earlier in
the week northeast of the airport. MVFR HZ/FU occurred last
night but the 21 UTC RAP is showing winds aloft light from the
south then northwest towards morning. With these trajectories
the smoke should disperse away from the airport.
Elsewhere, winds will become calm after sunset. Winds will
become west-southwest inland and souther at the coast after
1400 UTC with wind maximum winds speed of 6 to 8 knots.
Extended Outlook...There is a moderate chance of MVFR ceilings
Saturday night and Sunday. Otherwise VFR.
&&
.MARINE...
Through Saturday...Very quiet conditions to prevail across the
coastal waters under weak high pressure. Winds are expected to
maintain a southerly component with single digit wind speeds.
Significant seas of 1-2 feet expected.
Saturday Night through Wednesday...Light southwest flow
Saturday night will strengthen Sunday through Tuesday as high
pressure shifts offshore and several waves pass to the north
tightening the gradient. Winds peak late Sunday through Tuesday,
sustained 15-20 kts and gusts to 25 kt. Weak cold front drops
south Tuesday night with winds turning north-northeasterly on
Wednesday. Seas 2 ft Saturday night and Sunday build to 4-5 ft
for early Monday through early Tuesday with the S wind
wave/fresh swell. Seas drop to 2-3 ft Wednesday. Best chance for
scattered thunderstorms over the coastal waters in the short
term will be Monday evening/night as a shortwave passes over the
area.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...Coastal Flood Advisory until 1 AM EDT Saturday for NCZ107.
MARINE...None.
&&
$$
SYNOPSIS...ILM
UPDATE...RH
NEAR TERM...SHK
SHORT TERM...VAO
LONG TERM...VAO
AVIATION...RH
MARINE...SHK/VAO
Area Forecast Discussion
National Weather Service New Orleans LA
909 PM CDT Fri May 5 2023
...New UPDATE...
.UPDATE...
Issued at 902 PM CDT Fri May 5 2023
No significant changes anticipated to the overnight forecast.
Afternoon/evening convection is waning, with essentially one cell
remaining over Chandeleur/Breton Sounds. This will be handled with
the usual late evening CWF update. Areas that didn`t see evening
convection are a bit warmer than the hourly temperature grids
would indicate, but that`s not going to affect overnight lows any.
Early look at the 00z convection allowing models indicates that
the rest of the night should be quiet convectively, with
thunderstorms refiring during the mid to late morning hours across
western portions of the CWA. This is handled relatively well by
the current forecast package.
&&
.SHORT TERM...
(This evening through Saturday night)
Issued at 333 PM CDT Fri May 5 2023
As the previous update said it was a rather busy morning with the
convection quickly moving through the area but by 1430z it was
mostly confined to the Marine areas. After that we did warm up
quickly across most of the area and convection started to pop once
again but not quite as widespread as initially thought along the
boundary. Instead more convection refired over coastal Ms and the
Northshore while we are still watching a strong bow echo move
southeast out of south-central MS and towards southeastern/coastal
MS.
Biggest concern in the short term is the convection right now but
this activity should start to dissipate as we hit sunset with most
if not all of the rain done before 2z. Prior to that though not much
has changed from what was discussed in the midday update. There is a
lot of instability to tap into but mid lvl lapse rates may not be
quite as steep as previously thought. Boundary is still draped
across the region only slightly farther north than earlier but still
bisecting the region. The mid lvl flow is a little weaker over the
western half of the CWA and that may be what is leading to most of
the convection remaining mostly east of I-55. This activity will
likely continue to develop and increase in coverage over the next
few hours but as storms become more numerous the severe risk would
drop but the heavy rainfall potential will increase and localized
flash flooding could become a problem for poorly draining areas.
Again this activity should start to really shut down shortly after
sunset then the question is when and if we get another round or two
early tomorrow(around sunrise again) or just during the day. First
confidence is rather low with what happens tomorrow but really
leaning on the persistent GFS, 18z 3km NAM, and NBM. HRRR has been
all over the place, 12z says tomorrow will be nice and rain free
18z says maybe some storms. ECMWF has some really odd output
regarding convection during the day tomorrow which is interesting to
say the least and makes it highly questionable right now. The main
player is a subtle impulse that appears to be associated with
convection currently firing along the dryline in west/central TX.
If this is related then convection could be mid late morning
tomorrow and into the early afternoon hours. Possible fly in the
ointment would be if that convection consolidates into a large MCS
and tries to surge east again like last night/this morning.
Indications are that convection would wane and then refire so not
going to play the surging MCS while also maintaining its structure.
This would mean high rain chances for most of the area but it looks
like the best chance for storms would be across SELA. Southwest MS
may luck out and be just far enough north to miss the bulk of the
storms which would be great for all of the activities going on
tomorrow and tomorrow night up there.
As for impacts, not looking as favorable for strong to severe storms
as we probably won`t be quite as unstable thanks to rain clouds
already occuring during the prime hours to heat area. This will keep
the CAPE values down and lapse rates not as steep. Also outside of
the convective feedback issues the mid lvl flow doesn`t appear to be
nearly as strong. Locally heavy rain may be the bigger concern
especially if storms can`y move out fast enough. No change in the
available moisture with PWS still hovering just below 2" but much
like today no real jet dynamics to help with the divergence aloft
but possibly just some broad diffluence. Heavy rain likely to be
dictated by cell speed/interaction and/or training of storms.
Much quieter day on Sunday with the ridge dominating the region and
keeping the area rather warm. /CAB/
&&
.LONG TERM...
(Sunday through Thursday night)
Issued at 333 PM CDT Fri May 5 2023
Medium range models continue to indicate more of a Summer like
fee with warm LL temps leading to upper 80s and even lower 90s.
Daily rain chances given the mostly zonal flow with multiple weak
impulses coming across. Models significantly diverge for the back
half of the week. Otherwise with the focus primarily on today and
tomorrow no major changes made and the previous Long Term
Discussion has been appended below. /CAB/
Long Term...
Issued at 235 AM CDT Fri May 5 2023
We move into a very summer-like pattern during the week next week.
Global models are in good agreement through the forecast period.
With the good agreement, NBM outputs are used in the forecasting.
The models show an upper ridge of high pressure moving to the east
over the weekend bringing a somewhat barotropic pattern to the upper
levels. At the surface we fall between high pressure to the east and
low pressure to the west. A combination of shortwaves moving through
the upper levels and southerly winds between the two surface systems
bringing moisture out of the Gulf give a good setup for afternoon
convection. Rain and thunderstorms in the afternoon are on tap each
day with afternoon POPs running around 30%. No severe weather is
expected, although gusty winds (say 30mph) are possible and
lightning will accompany the thunderstorms. Temperatures will be in
the upper 80s to low 90s for highs and lows 70s overnight. With the
southerly flow out of the Gulf, RH values should remain above the
low 60%s even at the driest afternoon conditions. By the end of the
period, Thursday into Friday, upper ridging amplifies with a strong
low pressure system moving out of the Rockies and into the Great
Plains. [Schlotz]
&&
.AVIATION...
(00Z TAFS)
Issued at 630 PM CDT Fri May 5 2023
TSRA currently impacting KGPT and KASD, and could potentially
impact KNEW and KMSY over the next hour or two, with temporary IFR
or lower possible. Outside of convection, MVFR ceilings expected
later tonight with at least a low end threat of IFR conditions.
Once again, question on Saturday will be the potential for
convective development. Convection allowing models are again all
over the place regarding whether development occurs and where.
Looking at moisture availability on forecast soundings, certainly
enough moisture for convective development, so will approach it
carrying potential for development with VCTS.
&&
.MARINE...
Issued at 333 PM CDT Fri May 5 2023
A very persistent south to southeast wind of around 10 knots is
expected through the middle of next week as a broad ridge of high
pressure extends from the western Atlantic across Florida and into
the eastern Gulf of Mexico. Seas of 1 to 3 feet can be expected
with this onshore flow. The only big concern will be the threat of
locally strong wind gusts with any thunderstorm activity that
moves over the waters during the afternoon hours. This threat will
be highest in the tidal lakes and sounds. Otherwise, fairly
benign boating conditions will be place through the middle of next
week. /PG/
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 66 81 64 85 / 10 70 20 30
BTR 72 87 68 88 / 10 70 30 20
ASD 69 85 67 85 / 10 50 20 10
MSY 72 84 70 86 / 20 60 30 10
GPT 69 79 67 81 / 30 30 10 0
PQL 66 80 66 83 / 20 20 10 0
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...None.
MS...None.
GM...None.
&&
$$
SHORT TERM...CAB
LONG TERM....CAB
AVIATION/UPDATE...RW
MARINE...CAB
Area Forecast Discussion
National Weather Service Louisville KY
936 PM EDT Fri May 5 2023
.Forecast Update...
Issued at 935 PM EDT Fri May 5 2023
Current radar mosaic tile shows weak reflectivity cores moving west
to east across the area associated with subtle isentropic lifting.
Although there have been a couple of light rain/drizzle reports over
south-central Kentucky, overall this activity should wind down
towards midnight. Otherwise, this warm advection regime will keep
the broken to overcast conditions on Saturday with a low chance of
light rain/drizzle over the Lake Cumberland region before sunrise.
Regarding tomorrow`s forecast, did noticeable adjustments to account
for a drier solution, more in line with latest CAM guidance. The big
question remains the conditional risk of isolated convection in the
southwestern corner of the CWA which seems to stem from upstream
boundary collisions in the Mid Mississippi Valley. So far from the
HREF model suite, HRRR has been the most aggressive output followed
by the HRW ARW as the rest does not show any kind of significant
development. Subsequently, low probabilities were introduced for the
area of concern during the late afternoon period.
&&
.Short Term...(Tonight through Saturday evening)
Issued at 240 PM EDT Fri May 5 2023
Weakening band of light rain showers is making slow progress
eastward into our southern KY counties this hour. KY Mesonet is
showing a delayed response to any measurable precip, as that
moisture runs into drier air to the east..per GOES Sounder
precipitable water gradient. Given location of band moving into our
southern KY zones, will maintain low-end (~20%) chances for
measurable rainfall into the evening hours.
As mentioned in the previous discussion, there`s no good trigger or
low-level jetting to focus activity overnight as a little more solid
moisture builds into the area. Still, we may get some weak
isentropic lifting to force a few showers, so have gone with some
more low-end PoPs over a bit larger area of southern KY by daybreak
Saturday.
For the day Saturday, that pwat gradient shifts east, with most of
our area getting up to around 1.2"...a little above normal for this
time of year. Still with expected low cloud cover, we shouldn`t have
too many triggers for shower development. Ensemble guidance, both
short-range CAM`s and global model...aren`t too excited about rain
chances either. Still, any good breaks in those clouds through the
day could allow for some instability to form and promote an isolated
thunderstorm or two in the afternoon...so will maintain that mention
in this forecast package.
&&
.Long Term...(After midnight Saturday night through Friday)
Issued at 350 PM EDT Fri May 5 2023
As we head into the long-term, upper ridging remains in place
overhead while surface high pressure sits off the coast of South
Carolina. Surface low pressure near the panhandle of Oklahoma will
slowly get pushed northeast, increasing the pressure gradient over
the Lower Ohio Valley. The will keep breezy winds from the south
over the region. Lows Saturday night will only drop into the upper
50s to mid 60s. Even with warmer temperatures and a rising dew
point, most guidance keeps the region capped and dry, but it is
possible that an MCS that develops over Illinois could continue
working southeast through southern Indiana and central Kentucky
through the evening hours into the overnight. The HRRR has the
region remaining less capped and has the MCS working through the
region.
On Sunday, the day will likely begin with a few breaks in the clouds
allowing sunshine to help the the southern breeze lift temperatures
to the upper 70s to low 80s. Dew points are expected to climb into
the mid to upper 60s. The upper ridge and high pressure will keep
shear values low, but the warm moist air will help MLCAPE values
reach 2,000-3,000 J/kg by the evening hours. Model soundings show an
inversion sitting just above the 850mb layer of moisture, but it
wouldn`t take much to overcome this cap and for scattered
thunderstorms to develop. These storms could produce strong winds,
but organized severe weather isn`t expected. The chance for
scattered showers and thunderstorms will remain until a weak cold
front pushes through the region on Tuesday.
Behind the cold front, mostly sunny skies and weak CAA will drop
high temperatures on Wednesday a couple degrees before WAA returns
on Thursday. Temperatures on Thursday are expected to reach into the
low to mid 80s.
&&
.Aviation...(00Z TAF Issuance)
Issued at 730 PM EDT Fri May 5 2023
Impacts/Confidence:
- Low confidence in MVFR ceilings between 6/12-18Z at HNB/BWG/SDF
Discussion...Mainly VFR conditions are expected at all terminals
through this TAF period with a low chance of MVFR ceilings at
BWG/HNB/SDF Saturday morning. As noted in the previous forecast,
moisture continues building into the area ahead of an approaching
warm front. Regional radar imagery shows some decreasing echoes over
BWG which could yield some light rain but uneventful whatsoever.
Further north, latest SDF ACARS depicts plenty of dry air to
evaporate any precipitation attempt. Conditions overnight will be
mostly dry accompanied by light winds gradually shifting to the
south. Last but not least, southerly flow will slightly strengthen
Saturday morning while increasing moisture advection with a low
chance of cloud bases lowering to MVFR levels.
Extended Outlook...A period of lowered cloud base could start
Saturday night into Sunday morning with possibility of MVFR/IFR
category.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&
$$
Update...ALL
Short Term...RJS
Long Term...KDW
Aviation...ALL
Area Forecast Discussion
National Weather Service Shreveport LA
938 PM CDT Fri May 5 2023
...New UPDATE...
.UPDATE...
Issued at 935 PM CDT Fri May 5 2023
As of 9:30PM CDT, southerly winds continue to slacken as cloud
tops from showers and thunderstorms to our southwest drift
eastward. Muggy outdoor conditions are here to stay with the warm
frontal boundary continuing eastward overnight. Most short-term
guidance indicates that tonight`s round of showers and
thunderstorms over central Texas is expected to weaken as it moves
into east Texas with remnants potentially drifting into western
zones. With forecast grids accounting for this potential, no
additional edits were necessary at this time. /16/
&&
.SHORT TERM...
(This evening through Saturday Night)
Issued at 221 PM CDT Fri May 5 2023
The morning/afternoon convection has finally distanced itself
from the FA and with it some scattering of the cloud coverage
has prevailed. The previously mentioned stalled sfc boundary
across E/TX this afternoon looks to have finally begun some
forward motion just within the last hour or so as I type this. The
the boundary will move NE, passing through the FA entirely by the
time daybreak comes tomorrow morning. Given the passing boundary
so late in the day, and the continued southerly sfc flow
overnight, temperatures are expected remain warmer overnight for
many. Ranges in the upper 60s, low 70s are to be expected. This is
once again another increase from last nights MinT values. It is
possible that given the warmer values, decreasing winds and high
moisture content that some fog may develop. Not entirely sold at
this point, but will pass this along to the evening team who will
evaluate further and add any if confidence increases.
Similar to last night, we are once again closely monitoring
developing convection west of the FA across central TX that will
move east over the next several hours, getting close to our E/TX
counties after sunset. For now, hourly hi-res from the HRRR and
NAM Nest continues to highlight thunderstorm development west of
the CWA border, then quickly collapsing as it approaches the FA.
This is a different approach from the HRW panel including the
NSSL, ARW and FV3 solutions, all of which want to support
convection remaining healthy enough to work into the FA, falling
apart the closer it gets to the I-49 corridor after midnight,
potentially 1/2 AM. This is unfortunately the challenge within
this evenings forecast. It is very possible that the 12z HRW
solutions were anticipating the frontal boundary to already be
well east of where it`s present location is, helping to support an
environment that would sustain another MCS/MCV complex this
evening. A Marginal risk does exist across the extreme western
zones of the E/TX counties, stopping along the I-20 corridor
between Tyler and Longview. Primary concern would be damaging wind
at this time with whatever may hold together.
By Saturday, temperatures will begin to warm up behind the
boundary, but given the cloud coverage expected, this could delay
initial warming trends to start. Regardless, still expecting highs
in the upper 80s, near 90 deg F with select spots possibly
reaching 90 deg F. By the late evening, areas closer to the
passing front, mainly east zones, may spawn some afternoon style
convection that may spread as far west as I-49. Confidence is
mixed on this outcome and will need to be closely evaluated ahead
of future packages. This would be ahead of dryline thunderstorms
forecasted to fire west of DFW, and move east, building into the
SHV FA just ahead of midnight, before collapsing the further east
the complex moves into Sunday AM. Saturday night lows will fair
similar to Friday night, in the upper 60s, low 70s.
RK
&&
.LONG TERM...
(Sunday through next Thursday)
Issued at 221 PM CDT Fri May 5 2023
The long-term forecast period will be characterized by a persistent,
"dirty" southwest flow aloft featuring the passage of several
embedded, weak shortwave troughs. Any synoptic surface features that
could serve as sources for ascent or foci for convective development
(i.e., surface lows or frontal boundaries) should remain well to the
west and north of the forecast area. Combined with a warm, moist,
and unstable atmosphere, the result will likely be scattered
thunderstorms across a large part of the CWA on a nearly daily
basis. The greatest convective coverage should generally be in the
afternoon during peak diurnal heating, followed by a gradual
diminishing during the evening and nighttime hours. This type of a
pattern is incredibly difficult to forecast given weak forcing
mechanisms and lack of synoptic features to focus the convection.
Placement of the best PoPs each day will generally be driven by the
exact track of the weak shortwaves aloft and if there will be any
remnant outflow boundaries present from the previous day. Given the
time of year and the instability we should have, there will likely
be the chance for a couple of severe storms each day. Damaging winds
and large hail will be the primary risks.
The best chances for more widespread PoPs will be from Wednesday
morning through Thursday night. A couple of deeper shortwaves will
translate across the forecast area in advance of a much strong
trough that will move through the Rockies and into the Northern
Plains. The increased large scale forcing should help to increase
convective coverage across the region Wednesday afternoon and
Thursday afternoon, especially northwest of a line from Lufkin to El
Dorado. While the highest rain chances will continue to be during
the afternoon hours, there may be enough instability and forcing to
maintain at least some widely scattered showers and thunderstorms
through the nighttime and early morning hours Wednesday
night/Thursday morning and again Thursday night/Friday morning.
Daytime high temperatures should continue to be well into the 80s
during the long-term period. Temperatures each day will be governed
by convective effects and associated cloud cover. Locations that
stay precip-free on any given day will generally be warmer, and some
readings could climb into the upper 80s to near 90 degrees F. The
more widespread convection Wednesday and Thursday should bring
daytime highs back down into the lower to middle 80s.
CN
&&
.AVIATION...
(00Z TAFS)
Issued at 617 PM CDT Fri May 5 2023
For the 06/00Z TAF update, VFR vis/cigs are expected to
deteriorate to MVFR/IFR after 06/05Z with low-level moisture/cloud
cover until at least 06/14Z. Southerly surface flow will maintain
this environment with isolated chances of -TSRA/-RA by the end of
the period. /16/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 70 88 71 86 / 10 20 20 50
MLU 69 87 68 87 / 10 30 20 40
DEQ 65 87 68 85 / 10 10 20 40
TXK 68 88 70 87 / 10 10 20 40
ELD 68 87 68 85 / 10 30 20 40
TYR 70 89 70 87 / 20 10 20 40
GGG 69 88 70 86 / 20 10 20 50
LFK 71 90 70 86 / 20 10 20 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
SHORT TERM...16
LONG TERM....09
AVIATION...16